xref: /linux/fs/ext4/super.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/ext4/super.c
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/fs/minix/inode.c
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  *
16  *  Big-endian to little-endian byte-swapping/bitmaps by
17  *        David S. Miller (davem@caip.rutgers.edu), 1995
18  */
19 
20 #include <linux/module.h>
21 #include <linux/string.h>
22 #include <linux/fs.h>
23 #include <linux/time.h>
24 #include <linux/vmalloc.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/backing-dev.h>
29 #include <linux/parser.h>
30 #include <linux/buffer_head.h>
31 #include <linux/exportfs.h>
32 #include <linux/vfs.h>
33 #include <linux/random.h>
34 #include <linux/mount.h>
35 #include <linux/namei.h>
36 #include <linux/quotaops.h>
37 #include <linux/seq_file.h>
38 #include <linux/ctype.h>
39 #include <linux/log2.h>
40 #include <linux/crc16.h>
41 #include <linux/dax.h>
42 #include <linux/uaccess.h>
43 #include <linux/iversion.h>
44 #include <linux/unicode.h>
45 #include <linux/part_stat.h>
46 #include <linux/kthread.h>
47 #include <linux/freezer.h>
48 #include <linux/fsnotify.h>
49 #include <linux/fs_context.h>
50 #include <linux/fs_parser.h>
51 
52 #include "ext4.h"
53 #include "ext4_extents.h"	/* Needed for trace points definition */
54 #include "ext4_jbd2.h"
55 #include "xattr.h"
56 #include "acl.h"
57 #include "mballoc.h"
58 #include "fsmap.h"
59 
60 #define CREATE_TRACE_POINTS
61 #include <trace/events/ext4.h>
62 
63 static struct ext4_lazy_init *ext4_li_info;
64 static DEFINE_MUTEX(ext4_li_mtx);
65 static struct ratelimit_state ext4_mount_msg_ratelimit;
66 
67 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
68 			     unsigned long journal_devnum);
69 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
70 static void ext4_update_super(struct super_block *sb);
71 static int ext4_commit_super(struct super_block *sb);
72 static int ext4_mark_recovery_complete(struct super_block *sb,
73 					struct ext4_super_block *es);
74 static int ext4_clear_journal_err(struct super_block *sb,
75 				  struct ext4_super_block *es);
76 static int ext4_sync_fs(struct super_block *sb, int wait);
77 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
78 static int ext4_unfreeze(struct super_block *sb);
79 static int ext4_freeze(struct super_block *sb);
80 static inline int ext2_feature_set_ok(struct super_block *sb);
81 static inline int ext3_feature_set_ok(struct super_block *sb);
82 static void ext4_unregister_li_request(struct super_block *sb);
83 static void ext4_clear_request_list(void);
84 static struct inode *ext4_get_journal_inode(struct super_block *sb,
85 					    unsigned int journal_inum);
86 static int ext4_validate_options(struct fs_context *fc);
87 static int ext4_check_opt_consistency(struct fs_context *fc,
88 				      struct super_block *sb);
89 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb);
90 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param);
91 static int ext4_get_tree(struct fs_context *fc);
92 static int ext4_reconfigure(struct fs_context *fc);
93 static void ext4_fc_free(struct fs_context *fc);
94 static int ext4_init_fs_context(struct fs_context *fc);
95 static void ext4_kill_sb(struct super_block *sb);
96 static const struct fs_parameter_spec ext4_param_specs[];
97 
98 /*
99  * Lock ordering
100  *
101  * page fault path:
102  * mmap_lock -> sb_start_pagefault -> invalidate_lock (r) -> transaction start
103  *   -> page lock -> i_data_sem (rw)
104  *
105  * buffered write path:
106  * sb_start_write -> i_mutex -> mmap_lock
107  * sb_start_write -> i_mutex -> transaction start -> page lock ->
108  *   i_data_sem (rw)
109  *
110  * truncate:
111  * sb_start_write -> i_mutex -> invalidate_lock (w) -> i_mmap_rwsem (w) ->
112  *   page lock
113  * sb_start_write -> i_mutex -> invalidate_lock (w) -> transaction start ->
114  *   i_data_sem (rw)
115  *
116  * direct IO:
117  * sb_start_write -> i_mutex -> mmap_lock
118  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
119  *
120  * writepages:
121  * transaction start -> page lock(s) -> i_data_sem (rw)
122  */
123 
124 static const struct fs_context_operations ext4_context_ops = {
125 	.parse_param	= ext4_parse_param,
126 	.get_tree	= ext4_get_tree,
127 	.reconfigure	= ext4_reconfigure,
128 	.free		= ext4_fc_free,
129 };
130 
131 
132 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
133 static struct file_system_type ext2_fs_type = {
134 	.owner			= THIS_MODULE,
135 	.name			= "ext2",
136 	.init_fs_context	= ext4_init_fs_context,
137 	.parameters		= ext4_param_specs,
138 	.kill_sb		= ext4_kill_sb,
139 	.fs_flags		= FS_REQUIRES_DEV,
140 };
141 MODULE_ALIAS_FS("ext2");
142 MODULE_ALIAS("ext2");
143 #define IS_EXT2_SB(sb) ((sb)->s_type == &ext2_fs_type)
144 #else
145 #define IS_EXT2_SB(sb) (0)
146 #endif
147 
148 
149 static struct file_system_type ext3_fs_type = {
150 	.owner			= THIS_MODULE,
151 	.name			= "ext3",
152 	.init_fs_context	= ext4_init_fs_context,
153 	.parameters		= ext4_param_specs,
154 	.kill_sb		= ext4_kill_sb,
155 	.fs_flags		= FS_REQUIRES_DEV,
156 };
157 MODULE_ALIAS_FS("ext3");
158 MODULE_ALIAS("ext3");
159 #define IS_EXT3_SB(sb) ((sb)->s_type == &ext3_fs_type)
160 
161 
162 static inline void __ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
163 				  bh_end_io_t *end_io, bool simu_fail)
164 {
165 	if (simu_fail) {
166 		clear_buffer_uptodate(bh);
167 		unlock_buffer(bh);
168 		return;
169 	}
170 
171 	/*
172 	 * buffer's verified bit is no longer valid after reading from
173 	 * disk again due to write out error, clear it to make sure we
174 	 * recheck the buffer contents.
175 	 */
176 	clear_buffer_verified(bh);
177 
178 	bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
179 	get_bh(bh);
180 	submit_bh(REQ_OP_READ | op_flags, bh);
181 }
182 
183 void ext4_read_bh_nowait(struct buffer_head *bh, blk_opf_t op_flags,
184 			 bh_end_io_t *end_io, bool simu_fail)
185 {
186 	BUG_ON(!buffer_locked(bh));
187 
188 	if (ext4_buffer_uptodate(bh)) {
189 		unlock_buffer(bh);
190 		return;
191 	}
192 	__ext4_read_bh(bh, op_flags, end_io, simu_fail);
193 }
194 
195 int ext4_read_bh(struct buffer_head *bh, blk_opf_t op_flags,
196 		 bh_end_io_t *end_io, bool simu_fail)
197 {
198 	BUG_ON(!buffer_locked(bh));
199 
200 	if (ext4_buffer_uptodate(bh)) {
201 		unlock_buffer(bh);
202 		return 0;
203 	}
204 
205 	__ext4_read_bh(bh, op_flags, end_io, simu_fail);
206 
207 	wait_on_buffer(bh);
208 	if (buffer_uptodate(bh))
209 		return 0;
210 	return -EIO;
211 }
212 
213 int ext4_read_bh_lock(struct buffer_head *bh, blk_opf_t op_flags, bool wait)
214 {
215 	lock_buffer(bh);
216 	if (!wait) {
217 		ext4_read_bh_nowait(bh, op_flags, NULL, false);
218 		return 0;
219 	}
220 	return ext4_read_bh(bh, op_flags, NULL, false);
221 }
222 
223 /*
224  * This works like __bread_gfp() except it uses ERR_PTR for error
225  * returns.  Currently with sb_bread it's impossible to distinguish
226  * between ENOMEM and EIO situations (since both result in a NULL
227  * return.
228  */
229 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
230 					       sector_t block,
231 					       blk_opf_t op_flags, gfp_t gfp)
232 {
233 	struct buffer_head *bh;
234 	int ret;
235 
236 	bh = sb_getblk_gfp(sb, block, gfp);
237 	if (bh == NULL)
238 		return ERR_PTR(-ENOMEM);
239 	if (ext4_buffer_uptodate(bh))
240 		return bh;
241 
242 	ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
243 	if (ret) {
244 		put_bh(bh);
245 		return ERR_PTR(ret);
246 	}
247 	return bh;
248 }
249 
250 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
251 				   blk_opf_t op_flags)
252 {
253 	gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_mapping,
254 			~__GFP_FS) | __GFP_MOVABLE;
255 
256 	return __ext4_sb_bread_gfp(sb, block, op_flags, gfp);
257 }
258 
259 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
260 					    sector_t block)
261 {
262 	gfp_t gfp = mapping_gfp_constraint(sb->s_bdev->bd_mapping,
263 			~__GFP_FS);
264 
265 	return __ext4_sb_bread_gfp(sb, block, 0, gfp);
266 }
267 
268 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
269 {
270 	struct buffer_head *bh = bdev_getblk(sb->s_bdev, block,
271 			sb->s_blocksize, GFP_NOWAIT);
272 
273 	if (likely(bh)) {
274 		if (trylock_buffer(bh))
275 			ext4_read_bh_nowait(bh, REQ_RAHEAD, NULL, false);
276 		brelse(bh);
277 	}
278 }
279 
280 static int ext4_verify_csum_type(struct super_block *sb,
281 				 struct ext4_super_block *es)
282 {
283 	if (!ext4_has_feature_metadata_csum(sb))
284 		return 1;
285 
286 	return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
287 }
288 
289 __le32 ext4_superblock_csum(struct ext4_super_block *es)
290 {
291 	int offset = offsetof(struct ext4_super_block, s_checksum);
292 	__u32 csum;
293 
294 	csum = ext4_chksum(~0, (char *)es, offset);
295 
296 	return cpu_to_le32(csum);
297 }
298 
299 static int ext4_superblock_csum_verify(struct super_block *sb,
300 				       struct ext4_super_block *es)
301 {
302 	if (!ext4_has_feature_metadata_csum(sb))
303 		return 1;
304 
305 	return es->s_checksum == ext4_superblock_csum(es);
306 }
307 
308 void ext4_superblock_csum_set(struct super_block *sb)
309 {
310 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
311 
312 	if (!ext4_has_feature_metadata_csum(sb))
313 		return;
314 
315 	es->s_checksum = ext4_superblock_csum(es);
316 }
317 
318 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
319 			       struct ext4_group_desc *bg)
320 {
321 	return le32_to_cpu(bg->bg_block_bitmap_lo) |
322 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
323 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
324 }
325 
326 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
327 			       struct ext4_group_desc *bg)
328 {
329 	return le32_to_cpu(bg->bg_inode_bitmap_lo) |
330 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
331 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
332 }
333 
334 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
335 			      struct ext4_group_desc *bg)
336 {
337 	return le32_to_cpu(bg->bg_inode_table_lo) |
338 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
339 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
340 }
341 
342 __u32 ext4_free_group_clusters(struct super_block *sb,
343 			       struct ext4_group_desc *bg)
344 {
345 	return le16_to_cpu(bg->bg_free_blocks_count_lo) |
346 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
347 		 (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
348 }
349 
350 __u32 ext4_free_inodes_count(struct super_block *sb,
351 			      struct ext4_group_desc *bg)
352 {
353 	return le16_to_cpu(READ_ONCE(bg->bg_free_inodes_count_lo)) |
354 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
355 		 (__u32)le16_to_cpu(READ_ONCE(bg->bg_free_inodes_count_hi)) << 16 : 0);
356 }
357 
358 __u32 ext4_used_dirs_count(struct super_block *sb,
359 			      struct ext4_group_desc *bg)
360 {
361 	return le16_to_cpu(bg->bg_used_dirs_count_lo) |
362 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
363 		 (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
364 }
365 
366 __u32 ext4_itable_unused_count(struct super_block *sb,
367 			      struct ext4_group_desc *bg)
368 {
369 	return le16_to_cpu(bg->bg_itable_unused_lo) |
370 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
371 		 (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
372 }
373 
374 void ext4_block_bitmap_set(struct super_block *sb,
375 			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
376 {
377 	bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
378 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
379 		bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
380 }
381 
382 void ext4_inode_bitmap_set(struct super_block *sb,
383 			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
384 {
385 	bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
386 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
387 		bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
388 }
389 
390 void ext4_inode_table_set(struct super_block *sb,
391 			  struct ext4_group_desc *bg, ext4_fsblk_t blk)
392 {
393 	bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
394 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
395 		bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
396 }
397 
398 void ext4_free_group_clusters_set(struct super_block *sb,
399 				  struct ext4_group_desc *bg, __u32 count)
400 {
401 	bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
402 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
403 		bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
404 }
405 
406 void ext4_free_inodes_set(struct super_block *sb,
407 			  struct ext4_group_desc *bg, __u32 count)
408 {
409 	WRITE_ONCE(bg->bg_free_inodes_count_lo, cpu_to_le16((__u16)count));
410 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
411 		WRITE_ONCE(bg->bg_free_inodes_count_hi, cpu_to_le16(count >> 16));
412 }
413 
414 void ext4_used_dirs_set(struct super_block *sb,
415 			  struct ext4_group_desc *bg, __u32 count)
416 {
417 	bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
418 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
419 		bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
420 }
421 
422 void ext4_itable_unused_set(struct super_block *sb,
423 			  struct ext4_group_desc *bg, __u32 count)
424 {
425 	bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
426 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
427 		bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
428 }
429 
430 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi, time64_t now)
431 {
432 	now = clamp_val(now, 0, (1ull << 40) - 1);
433 
434 	*lo = cpu_to_le32(lower_32_bits(now));
435 	*hi = upper_32_bits(now);
436 }
437 
438 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
439 {
440 	return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
441 }
442 #define ext4_update_tstamp(es, tstamp) \
443 	__ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi, \
444 			     ktime_get_real_seconds())
445 #define ext4_get_tstamp(es, tstamp) \
446 	__ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
447 
448 /*
449  * The ext4_maybe_update_superblock() function checks and updates the
450  * superblock if needed.
451  *
452  * This function is designed to update the on-disk superblock only under
453  * certain conditions to prevent excessive disk writes and unnecessary
454  * waking of the disk from sleep. The superblock will be updated if:
455  * 1. More than sbi->s_sb_update_sec (def: 1 hour) has passed since the last
456  *    superblock update
457  * 2. More than sbi->s_sb_update_kb (def: 16MB) kbs have been written since the
458  *    last superblock update.
459  *
460  * @sb: The superblock
461  */
462 static void ext4_maybe_update_superblock(struct super_block *sb)
463 {
464 	struct ext4_sb_info *sbi = EXT4_SB(sb);
465 	struct ext4_super_block *es = sbi->s_es;
466 	journal_t *journal = sbi->s_journal;
467 	time64_t now;
468 	__u64 last_update;
469 	__u64 lifetime_write_kbytes;
470 	__u64 diff_size;
471 
472 	if (ext4_emergency_state(sb) || sb_rdonly(sb) ||
473 	    !(sb->s_flags & SB_ACTIVE) || !journal ||
474 	    journal->j_flags & JBD2_UNMOUNT)
475 		return;
476 
477 	now = ktime_get_real_seconds();
478 	last_update = ext4_get_tstamp(es, s_wtime);
479 
480 	if (likely(now - last_update < sbi->s_sb_update_sec))
481 		return;
482 
483 	lifetime_write_kbytes = sbi->s_kbytes_written +
484 		((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
485 		  sbi->s_sectors_written_start) >> 1);
486 
487 	/* Get the number of kilobytes not written to disk to account
488 	 * for statistics and compare with a multiple of 16 MB. This
489 	 * is used to determine when the next superblock commit should
490 	 * occur (i.e. not more often than once per 16MB if there was
491 	 * less written in an hour).
492 	 */
493 	diff_size = lifetime_write_kbytes - le64_to_cpu(es->s_kbytes_written);
494 
495 	if (diff_size > sbi->s_sb_update_kb)
496 		schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
497 }
498 
499 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
500 {
501 	struct super_block		*sb = journal->j_private;
502 
503 	BUG_ON(txn->t_state == T_FINISHED);
504 
505 	ext4_process_freed_data(sb, txn->t_tid);
506 	ext4_maybe_update_superblock(sb);
507 }
508 
509 static bool ext4_journalled_writepage_needs_redirty(struct jbd2_inode *jinode,
510 		struct folio *folio)
511 {
512 	struct buffer_head *bh, *head;
513 	struct journal_head *jh;
514 
515 	bh = head = folio_buffers(folio);
516 	do {
517 		/*
518 		 * We have to redirty a page in these cases:
519 		 * 1) If buffer is dirty, it means the page was dirty because it
520 		 * contains a buffer that needs checkpointing. So the dirty bit
521 		 * needs to be preserved so that checkpointing writes the buffer
522 		 * properly.
523 		 * 2) If buffer is not part of the committing transaction
524 		 * (we may have just accidentally come across this buffer because
525 		 * inode range tracking is not exact) or if the currently running
526 		 * transaction already contains this buffer as well, dirty bit
527 		 * needs to be preserved so that the buffer gets writeprotected
528 		 * properly on running transaction's commit.
529 		 */
530 		jh = bh2jh(bh);
531 		if (buffer_dirty(bh) ||
532 		    (jh && (jh->b_transaction != jinode->i_transaction ||
533 			    jh->b_next_transaction)))
534 			return true;
535 	} while ((bh = bh->b_this_page) != head);
536 
537 	return false;
538 }
539 
540 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
541 {
542 	struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
543 	struct writeback_control wbc = {
544 		.sync_mode =  WB_SYNC_ALL,
545 		.nr_to_write = LONG_MAX,
546 		.range_start = jinode->i_dirty_start,
547 		.range_end = jinode->i_dirty_end,
548         };
549 	struct folio *folio = NULL;
550 	int error;
551 
552 	/*
553 	 * writeback_iter() already checks for dirty pages and calls
554 	 * folio_clear_dirty_for_io(), which we want to write protect the
555 	 * folios.
556 	 *
557 	 * However, we may have to redirty a folio sometimes.
558 	 */
559 	while ((folio = writeback_iter(mapping, &wbc, folio, &error))) {
560 		if (ext4_journalled_writepage_needs_redirty(jinode, folio))
561 			folio_redirty_for_writepage(&wbc, folio);
562 		folio_unlock(folio);
563 	}
564 
565 	return error;
566 }
567 
568 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
569 {
570 	int ret;
571 
572 	if (ext4_should_journal_data(jinode->i_vfs_inode))
573 		ret = ext4_journalled_submit_inode_data_buffers(jinode);
574 	else
575 		ret = ext4_normal_submit_inode_data_buffers(jinode);
576 	return ret;
577 }
578 
579 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
580 {
581 	int ret = 0;
582 
583 	if (!ext4_should_journal_data(jinode->i_vfs_inode))
584 		ret = jbd2_journal_finish_inode_data_buffers(jinode);
585 
586 	return ret;
587 }
588 
589 static bool system_going_down(void)
590 {
591 	return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
592 		|| system_state == SYSTEM_RESTART;
593 }
594 
595 struct ext4_err_translation {
596 	int code;
597 	int errno;
598 };
599 
600 #define EXT4_ERR_TRANSLATE(err) { .code = EXT4_ERR_##err, .errno = err }
601 
602 static struct ext4_err_translation err_translation[] = {
603 	EXT4_ERR_TRANSLATE(EIO),
604 	EXT4_ERR_TRANSLATE(ENOMEM),
605 	EXT4_ERR_TRANSLATE(EFSBADCRC),
606 	EXT4_ERR_TRANSLATE(EFSCORRUPTED),
607 	EXT4_ERR_TRANSLATE(ENOSPC),
608 	EXT4_ERR_TRANSLATE(ENOKEY),
609 	EXT4_ERR_TRANSLATE(EROFS),
610 	EXT4_ERR_TRANSLATE(EFBIG),
611 	EXT4_ERR_TRANSLATE(EEXIST),
612 	EXT4_ERR_TRANSLATE(ERANGE),
613 	EXT4_ERR_TRANSLATE(EOVERFLOW),
614 	EXT4_ERR_TRANSLATE(EBUSY),
615 	EXT4_ERR_TRANSLATE(ENOTDIR),
616 	EXT4_ERR_TRANSLATE(ENOTEMPTY),
617 	EXT4_ERR_TRANSLATE(ESHUTDOWN),
618 	EXT4_ERR_TRANSLATE(EFAULT),
619 };
620 
621 static int ext4_errno_to_code(int errno)
622 {
623 	int i;
624 
625 	for (i = 0; i < ARRAY_SIZE(err_translation); i++)
626 		if (err_translation[i].errno == errno)
627 			return err_translation[i].code;
628 	return EXT4_ERR_UNKNOWN;
629 }
630 
631 static void save_error_info(struct super_block *sb, int error,
632 			    __u32 ino, __u64 block,
633 			    const char *func, unsigned int line)
634 {
635 	struct ext4_sb_info *sbi = EXT4_SB(sb);
636 
637 	/* We default to EFSCORRUPTED error... */
638 	if (error == 0)
639 		error = EFSCORRUPTED;
640 
641 	spin_lock(&sbi->s_error_lock);
642 	sbi->s_add_error_count++;
643 	sbi->s_last_error_code = error;
644 	sbi->s_last_error_line = line;
645 	sbi->s_last_error_ino = ino;
646 	sbi->s_last_error_block = block;
647 	sbi->s_last_error_func = func;
648 	sbi->s_last_error_time = ktime_get_real_seconds();
649 	if (!sbi->s_first_error_time) {
650 		sbi->s_first_error_code = error;
651 		sbi->s_first_error_line = line;
652 		sbi->s_first_error_ino = ino;
653 		sbi->s_first_error_block = block;
654 		sbi->s_first_error_func = func;
655 		sbi->s_first_error_time = sbi->s_last_error_time;
656 	}
657 	spin_unlock(&sbi->s_error_lock);
658 }
659 
660 /* Deal with the reporting of failure conditions on a filesystem such as
661  * inconsistencies detected or read IO failures.
662  *
663  * On ext2, we can store the error state of the filesystem in the
664  * superblock.  That is not possible on ext4, because we may have other
665  * write ordering constraints on the superblock which prevent us from
666  * writing it out straight away; and given that the journal is about to
667  * be aborted, we can't rely on the current, or future, transactions to
668  * write out the superblock safely.
669  *
670  * We'll just use the jbd2_journal_abort() error code to record an error in
671  * the journal instead.  On recovery, the journal will complain about
672  * that error until we've noted it down and cleared it.
673  *
674  * If force_ro is set, we unconditionally force the filesystem into an
675  * ABORT|READONLY state, unless the error response on the fs has been set to
676  * panic in which case we take the easy way out and panic immediately. This is
677  * used to deal with unrecoverable failures such as journal IO errors or ENOMEM
678  * at a critical moment in log management.
679  */
680 static void ext4_handle_error(struct super_block *sb, bool force_ro, int error,
681 			      __u32 ino, __u64 block,
682 			      const char *func, unsigned int line)
683 {
684 	journal_t *journal = EXT4_SB(sb)->s_journal;
685 	bool continue_fs = !force_ro && test_opt(sb, ERRORS_CONT);
686 
687 	EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
688 	if (test_opt(sb, WARN_ON_ERROR))
689 		WARN_ON_ONCE(1);
690 
691 	if (!continue_fs && !ext4_emergency_ro(sb) && journal)
692 		jbd2_journal_abort(journal, -EIO);
693 
694 	if (!bdev_read_only(sb->s_bdev)) {
695 		save_error_info(sb, error, ino, block, func, line);
696 		/*
697 		 * In case the fs should keep running, we need to writeout
698 		 * superblock through the journal. Due to lock ordering
699 		 * constraints, it may not be safe to do it right here so we
700 		 * defer superblock flushing to a workqueue. We just need to be
701 		 * careful when the journal is already shutting down. If we get
702 		 * here in that case, just update the sb directly as the last
703 		 * transaction won't commit anyway.
704 		 */
705 		if (continue_fs && journal &&
706 		    !ext4_test_mount_flag(sb, EXT4_MF_JOURNAL_DESTROY))
707 			schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
708 		else
709 			ext4_commit_super(sb);
710 	}
711 
712 	/*
713 	 * We force ERRORS_RO behavior when system is rebooting. Otherwise we
714 	 * could panic during 'reboot -f' as the underlying device got already
715 	 * disabled.
716 	 */
717 	if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
718 		panic("EXT4-fs (device %s): panic forced after error\n",
719 			sb->s_id);
720 	}
721 
722 	if (ext4_emergency_ro(sb) || continue_fs)
723 		return;
724 
725 	ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
726 	/*
727 	 * We don't set SB_RDONLY because that requires sb->s_umount
728 	 * semaphore and setting it without proper remount procedure is
729 	 * confusing code such as freeze_super() leading to deadlocks
730 	 * and other problems.
731 	 */
732 	set_bit(EXT4_FLAGS_EMERGENCY_RO, &EXT4_SB(sb)->s_ext4_flags);
733 }
734 
735 static void update_super_work(struct work_struct *work)
736 {
737 	struct ext4_sb_info *sbi = container_of(work, struct ext4_sb_info,
738 						s_sb_upd_work);
739 	journal_t *journal = sbi->s_journal;
740 	handle_t *handle;
741 
742 	/*
743 	 * If the journal is still running, we have to write out superblock
744 	 * through the journal to avoid collisions of other journalled sb
745 	 * updates.
746 	 *
747 	 * We use directly jbd2 functions here to avoid recursing back into
748 	 * ext4 error handling code during handling of previous errors.
749 	 */
750 	if (!ext4_emergency_state(sbi->s_sb) &&
751 	    !sb_rdonly(sbi->s_sb) && journal) {
752 		struct buffer_head *sbh = sbi->s_sbh;
753 		bool call_notify_err = false;
754 
755 		handle = jbd2_journal_start(journal, 1);
756 		if (IS_ERR(handle))
757 			goto write_directly;
758 		if (jbd2_journal_get_write_access(handle, sbh)) {
759 			jbd2_journal_stop(handle);
760 			goto write_directly;
761 		}
762 
763 		if (sbi->s_add_error_count > 0)
764 			call_notify_err = true;
765 
766 		ext4_update_super(sbi->s_sb);
767 		if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
768 			ext4_msg(sbi->s_sb, KERN_ERR, "previous I/O error to "
769 				 "superblock detected");
770 			clear_buffer_write_io_error(sbh);
771 			set_buffer_uptodate(sbh);
772 		}
773 
774 		if (jbd2_journal_dirty_metadata(handle, sbh)) {
775 			jbd2_journal_stop(handle);
776 			goto write_directly;
777 		}
778 		jbd2_journal_stop(handle);
779 
780 		if (call_notify_err)
781 			ext4_notify_error_sysfs(sbi);
782 
783 		return;
784 	}
785 write_directly:
786 	/*
787 	 * Write through journal failed. Write sb directly to get error info
788 	 * out and hope for the best.
789 	 */
790 	ext4_commit_super(sbi->s_sb);
791 	ext4_notify_error_sysfs(sbi);
792 }
793 
794 #define ext4_error_ratelimit(sb)					\
795 		___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),	\
796 			     "EXT4-fs error")
797 
798 void __ext4_error(struct super_block *sb, const char *function,
799 		  unsigned int line, bool force_ro, int error, __u64 block,
800 		  const char *fmt, ...)
801 {
802 	struct va_format vaf;
803 	va_list args;
804 
805 	if (unlikely(ext4_emergency_state(sb)))
806 		return;
807 
808 	trace_ext4_error(sb, function, line);
809 	if (ext4_error_ratelimit(sb)) {
810 		va_start(args, fmt);
811 		vaf.fmt = fmt;
812 		vaf.va = &args;
813 		printk(KERN_CRIT
814 		       "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
815 		       sb->s_id, function, line, current->comm, &vaf);
816 		va_end(args);
817 	}
818 	fsnotify_sb_error(sb, NULL, error ? error : EFSCORRUPTED);
819 
820 	ext4_handle_error(sb, force_ro, error, 0, block, function, line);
821 }
822 
823 void __ext4_error_inode(struct inode *inode, const char *function,
824 			unsigned int line, ext4_fsblk_t block, int error,
825 			const char *fmt, ...)
826 {
827 	va_list args;
828 	struct va_format vaf;
829 
830 	if (unlikely(ext4_emergency_state(inode->i_sb)))
831 		return;
832 
833 	trace_ext4_error(inode->i_sb, function, line);
834 	if (ext4_error_ratelimit(inode->i_sb)) {
835 		va_start(args, fmt);
836 		vaf.fmt = fmt;
837 		vaf.va = &args;
838 		if (block)
839 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
840 			       "inode #%lu: block %llu: comm %s: %pV\n",
841 			       inode->i_sb->s_id, function, line, inode->i_ino,
842 			       block, current->comm, &vaf);
843 		else
844 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
845 			       "inode #%lu: comm %s: %pV\n",
846 			       inode->i_sb->s_id, function, line, inode->i_ino,
847 			       current->comm, &vaf);
848 		va_end(args);
849 	}
850 	fsnotify_sb_error(inode->i_sb, inode, error ? error : EFSCORRUPTED);
851 
852 	ext4_handle_error(inode->i_sb, false, error, inode->i_ino, block,
853 			  function, line);
854 }
855 
856 void __ext4_error_file(struct file *file, const char *function,
857 		       unsigned int line, ext4_fsblk_t block,
858 		       const char *fmt, ...)
859 {
860 	va_list args;
861 	struct va_format vaf;
862 	struct inode *inode = file_inode(file);
863 	char pathname[80], *path;
864 
865 	if (unlikely(ext4_emergency_state(inode->i_sb)))
866 		return;
867 
868 	trace_ext4_error(inode->i_sb, function, line);
869 	if (ext4_error_ratelimit(inode->i_sb)) {
870 		path = file_path(file, pathname, sizeof(pathname));
871 		if (IS_ERR(path))
872 			path = "(unknown)";
873 		va_start(args, fmt);
874 		vaf.fmt = fmt;
875 		vaf.va = &args;
876 		if (block)
877 			printk(KERN_CRIT
878 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
879 			       "block %llu: comm %s: path %s: %pV\n",
880 			       inode->i_sb->s_id, function, line, inode->i_ino,
881 			       block, current->comm, path, &vaf);
882 		else
883 			printk(KERN_CRIT
884 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
885 			       "comm %s: path %s: %pV\n",
886 			       inode->i_sb->s_id, function, line, inode->i_ino,
887 			       current->comm, path, &vaf);
888 		va_end(args);
889 	}
890 	fsnotify_sb_error(inode->i_sb, inode, EFSCORRUPTED);
891 
892 	ext4_handle_error(inode->i_sb, false, EFSCORRUPTED, inode->i_ino, block,
893 			  function, line);
894 }
895 
896 const char *ext4_decode_error(struct super_block *sb, int errno,
897 			      char nbuf[16])
898 {
899 	char *errstr = NULL;
900 
901 	switch (errno) {
902 	case -EFSCORRUPTED:
903 		errstr = "Corrupt filesystem";
904 		break;
905 	case -EFSBADCRC:
906 		errstr = "Filesystem failed CRC";
907 		break;
908 	case -EIO:
909 		errstr = "IO failure";
910 		break;
911 	case -ENOMEM:
912 		errstr = "Out of memory";
913 		break;
914 	case -EROFS:
915 		if (!sb || (EXT4_SB(sb)->s_journal &&
916 			    EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
917 			errstr = "Journal has aborted";
918 		else
919 			errstr = "Readonly filesystem";
920 		break;
921 	default:
922 		/* If the caller passed in an extra buffer for unknown
923 		 * errors, textualise them now.  Else we just return
924 		 * NULL. */
925 		if (nbuf) {
926 			/* Check for truncated error codes... */
927 			if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
928 				errstr = nbuf;
929 		}
930 		break;
931 	}
932 
933 	return errstr;
934 }
935 
936 /* __ext4_std_error decodes expected errors from journaling functions
937  * automatically and invokes the appropriate error response.  */
938 
939 void __ext4_std_error(struct super_block *sb, const char *function,
940 		      unsigned int line, int errno)
941 {
942 	char nbuf[16];
943 	const char *errstr;
944 
945 	if (unlikely(ext4_emergency_state(sb)))
946 		return;
947 
948 	/* Special case: if the error is EROFS, and we're not already
949 	 * inside a transaction, then there's really no point in logging
950 	 * an error. */
951 	if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
952 		return;
953 
954 	if (ext4_error_ratelimit(sb)) {
955 		errstr = ext4_decode_error(sb, errno, nbuf);
956 		printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
957 		       sb->s_id, function, line, errstr);
958 	}
959 	fsnotify_sb_error(sb, NULL, errno ? errno : EFSCORRUPTED);
960 
961 	ext4_handle_error(sb, false, -errno, 0, 0, function, line);
962 }
963 
964 void __ext4_msg(struct super_block *sb,
965 		const char *prefix, const char *fmt, ...)
966 {
967 	struct va_format vaf;
968 	va_list args;
969 
970 	if (sb) {
971 		atomic_inc(&EXT4_SB(sb)->s_msg_count);
972 		if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state),
973 				  "EXT4-fs"))
974 			return;
975 	}
976 
977 	va_start(args, fmt);
978 	vaf.fmt = fmt;
979 	vaf.va = &args;
980 	if (sb)
981 		printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
982 	else
983 		printk("%sEXT4-fs: %pV\n", prefix, &vaf);
984 	va_end(args);
985 }
986 
987 static int ext4_warning_ratelimit(struct super_block *sb)
988 {
989 	atomic_inc(&EXT4_SB(sb)->s_warning_count);
990 	return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
991 			    "EXT4-fs warning");
992 }
993 
994 void __ext4_warning(struct super_block *sb, const char *function,
995 		    unsigned int line, const char *fmt, ...)
996 {
997 	struct va_format vaf;
998 	va_list args;
999 
1000 	if (!ext4_warning_ratelimit(sb))
1001 		return;
1002 
1003 	va_start(args, fmt);
1004 	vaf.fmt = fmt;
1005 	vaf.va = &args;
1006 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
1007 	       sb->s_id, function, line, &vaf);
1008 	va_end(args);
1009 }
1010 
1011 void __ext4_warning_inode(const struct inode *inode, const char *function,
1012 			  unsigned int line, const char *fmt, ...)
1013 {
1014 	struct va_format vaf;
1015 	va_list args;
1016 
1017 	if (!ext4_warning_ratelimit(inode->i_sb))
1018 		return;
1019 
1020 	va_start(args, fmt);
1021 	vaf.fmt = fmt;
1022 	vaf.va = &args;
1023 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
1024 	       "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
1025 	       function, line, inode->i_ino, current->comm, &vaf);
1026 	va_end(args);
1027 }
1028 
1029 void __ext4_grp_locked_error(const char *function, unsigned int line,
1030 			     struct super_block *sb, ext4_group_t grp,
1031 			     unsigned long ino, ext4_fsblk_t block,
1032 			     const char *fmt, ...)
1033 __releases(bitlock)
1034 __acquires(bitlock)
1035 {
1036 	struct va_format vaf;
1037 	va_list args;
1038 
1039 	if (unlikely(ext4_emergency_state(sb)))
1040 		return;
1041 
1042 	trace_ext4_error(sb, function, line);
1043 	if (ext4_error_ratelimit(sb)) {
1044 		va_start(args, fmt);
1045 		vaf.fmt = fmt;
1046 		vaf.va = &args;
1047 		printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
1048 		       sb->s_id, function, line, grp);
1049 		if (ino)
1050 			printk(KERN_CONT "inode %lu: ", ino);
1051 		if (block)
1052 			printk(KERN_CONT "block %llu:",
1053 			       (unsigned long long) block);
1054 		printk(KERN_CONT "%pV\n", &vaf);
1055 		va_end(args);
1056 	}
1057 
1058 	if (test_opt(sb, ERRORS_CONT)) {
1059 		if (test_opt(sb, WARN_ON_ERROR))
1060 			WARN_ON_ONCE(1);
1061 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
1062 		if (!bdev_read_only(sb->s_bdev)) {
1063 			save_error_info(sb, EFSCORRUPTED, ino, block, function,
1064 					line);
1065 			schedule_work(&EXT4_SB(sb)->s_sb_upd_work);
1066 		}
1067 		return;
1068 	}
1069 	ext4_unlock_group(sb, grp);
1070 	ext4_handle_error(sb, false, EFSCORRUPTED, ino, block, function, line);
1071 	/*
1072 	 * We only get here in the ERRORS_RO case; relocking the group
1073 	 * may be dangerous, but nothing bad will happen since the
1074 	 * filesystem will have already been marked read/only and the
1075 	 * journal has been aborted.  We return 1 as a hint to callers
1076 	 * who might what to use the return value from
1077 	 * ext4_grp_locked_error() to distinguish between the
1078 	 * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1079 	 * aggressively from the ext4 function in question, with a
1080 	 * more appropriate error code.
1081 	 */
1082 	ext4_lock_group(sb, grp);
1083 	return;
1084 }
1085 
1086 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1087 				     ext4_group_t group,
1088 				     unsigned int flags)
1089 {
1090 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1091 	struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1092 	struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1093 	int ret;
1094 
1095 	if (!grp || !gdp)
1096 		return;
1097 	if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1098 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1099 					    &grp->bb_state);
1100 		if (!ret)
1101 			percpu_counter_sub(&sbi->s_freeclusters_counter,
1102 					   grp->bb_free);
1103 	}
1104 
1105 	if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1106 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1107 					    &grp->bb_state);
1108 		if (!ret && gdp) {
1109 			int count;
1110 
1111 			count = ext4_free_inodes_count(sb, gdp);
1112 			percpu_counter_sub(&sbi->s_freeinodes_counter,
1113 					   count);
1114 		}
1115 	}
1116 }
1117 
1118 void ext4_update_dynamic_rev(struct super_block *sb)
1119 {
1120 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1121 
1122 	if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1123 		return;
1124 
1125 	ext4_warning(sb,
1126 		     "updating to rev %d because of new feature flag, "
1127 		     "running e2fsck is recommended",
1128 		     EXT4_DYNAMIC_REV);
1129 
1130 	es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1131 	es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1132 	es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1133 	/* leave es->s_feature_*compat flags alone */
1134 	/* es->s_uuid will be set by e2fsck if empty */
1135 
1136 	/*
1137 	 * The rest of the superblock fields should be zero, and if not it
1138 	 * means they are likely already in use, so leave them alone.  We
1139 	 * can leave it up to e2fsck to clean up any inconsistencies there.
1140 	 */
1141 }
1142 
1143 static inline struct inode *orphan_list_entry(struct list_head *l)
1144 {
1145 	return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1146 }
1147 
1148 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1149 {
1150 	struct list_head *l;
1151 
1152 	ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1153 		 le32_to_cpu(sbi->s_es->s_last_orphan));
1154 
1155 	printk(KERN_ERR "sb_info orphan list:\n");
1156 	list_for_each(l, &sbi->s_orphan) {
1157 		struct inode *inode = orphan_list_entry(l);
1158 		printk(KERN_ERR "  "
1159 		       "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1160 		       inode->i_sb->s_id, inode->i_ino, inode,
1161 		       inode->i_mode, inode->i_nlink,
1162 		       NEXT_ORPHAN(inode));
1163 	}
1164 }
1165 
1166 #ifdef CONFIG_QUOTA
1167 static int ext4_quota_off(struct super_block *sb, int type);
1168 
1169 static inline void ext4_quotas_off(struct super_block *sb, int type)
1170 {
1171 	BUG_ON(type > EXT4_MAXQUOTAS);
1172 
1173 	/* Use our quota_off function to clear inode flags etc. */
1174 	for (type--; type >= 0; type--)
1175 		ext4_quota_off(sb, type);
1176 }
1177 
1178 /*
1179  * This is a helper function which is used in the mount/remount
1180  * codepaths (which holds s_umount) to fetch the quota file name.
1181  */
1182 static inline char *get_qf_name(struct super_block *sb,
1183 				struct ext4_sb_info *sbi,
1184 				int type)
1185 {
1186 	return rcu_dereference_protected(sbi->s_qf_names[type],
1187 					 lockdep_is_held(&sb->s_umount));
1188 }
1189 #else
1190 static inline void ext4_quotas_off(struct super_block *sb, int type)
1191 {
1192 }
1193 #endif
1194 
1195 static int ext4_percpu_param_init(struct ext4_sb_info *sbi)
1196 {
1197 	ext4_fsblk_t block;
1198 	int err;
1199 
1200 	block = ext4_count_free_clusters(sbi->s_sb);
1201 	ext4_free_blocks_count_set(sbi->s_es, EXT4_C2B(sbi, block));
1202 	err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
1203 				  GFP_KERNEL);
1204 	if (!err) {
1205 		unsigned long freei = ext4_count_free_inodes(sbi->s_sb);
1206 		sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
1207 		err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
1208 					  GFP_KERNEL);
1209 	}
1210 	if (!err)
1211 		err = percpu_counter_init(&sbi->s_dirs_counter,
1212 					  ext4_count_dirs(sbi->s_sb), GFP_KERNEL);
1213 	if (!err)
1214 		err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
1215 					  GFP_KERNEL);
1216 	if (!err)
1217 		err = percpu_counter_init(&sbi->s_sra_exceeded_retry_limit, 0,
1218 					  GFP_KERNEL);
1219 	if (!err)
1220 		err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
1221 
1222 	if (err)
1223 		ext4_msg(sbi->s_sb, KERN_ERR, "insufficient memory");
1224 
1225 	return err;
1226 }
1227 
1228 static void ext4_percpu_param_destroy(struct ext4_sb_info *sbi)
1229 {
1230 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
1231 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
1232 	percpu_counter_destroy(&sbi->s_dirs_counter);
1233 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1234 	percpu_counter_destroy(&sbi->s_sra_exceeded_retry_limit);
1235 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
1236 }
1237 
1238 static void ext4_group_desc_free(struct ext4_sb_info *sbi)
1239 {
1240 	struct buffer_head **group_desc;
1241 	int i;
1242 
1243 	rcu_read_lock();
1244 	group_desc = rcu_dereference(sbi->s_group_desc);
1245 	for (i = 0; i < sbi->s_gdb_count; i++)
1246 		brelse(group_desc[i]);
1247 	kvfree(group_desc);
1248 	rcu_read_unlock();
1249 }
1250 
1251 static void ext4_flex_groups_free(struct ext4_sb_info *sbi)
1252 {
1253 	struct flex_groups **flex_groups;
1254 	int i;
1255 
1256 	rcu_read_lock();
1257 	flex_groups = rcu_dereference(sbi->s_flex_groups);
1258 	if (flex_groups) {
1259 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1260 			kvfree(flex_groups[i]);
1261 		kvfree(flex_groups);
1262 	}
1263 	rcu_read_unlock();
1264 }
1265 
1266 static void ext4_put_super(struct super_block *sb)
1267 {
1268 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1269 	struct ext4_super_block *es = sbi->s_es;
1270 	int aborted = 0;
1271 	int err;
1272 
1273 	/*
1274 	 * Unregister sysfs before destroying jbd2 journal.
1275 	 * Since we could still access attr_journal_task attribute via sysfs
1276 	 * path which could have sbi->s_journal->j_task as NULL
1277 	 * Unregister sysfs before flush sbi->s_sb_upd_work.
1278 	 * Since user may read /proc/fs/ext4/xx/mb_groups during umount, If
1279 	 * read metadata verify failed then will queue error work.
1280 	 * update_super_work will call start_this_handle may trigger
1281 	 * BUG_ON.
1282 	 */
1283 	ext4_unregister_sysfs(sb);
1284 
1285 	if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs unmount"))
1286 		ext4_msg(sb, KERN_INFO, "unmounting filesystem %pU.",
1287 			 &sb->s_uuid);
1288 
1289 	ext4_unregister_li_request(sb);
1290 	ext4_quotas_off(sb, EXT4_MAXQUOTAS);
1291 
1292 	destroy_workqueue(sbi->rsv_conversion_wq);
1293 	ext4_release_orphan_info(sb);
1294 
1295 	if (sbi->s_journal) {
1296 		aborted = is_journal_aborted(sbi->s_journal);
1297 		err = ext4_journal_destroy(sbi, sbi->s_journal);
1298 		if ((err < 0) && !aborted) {
1299 			ext4_abort(sb, -err, "Couldn't clean up the journal");
1300 		}
1301 	} else
1302 		flush_work(&sbi->s_sb_upd_work);
1303 
1304 	ext4_es_unregister_shrinker(sbi);
1305 	timer_shutdown_sync(&sbi->s_err_report);
1306 	ext4_release_system_zone(sb);
1307 	ext4_mb_release(sb);
1308 	ext4_ext_release(sb);
1309 
1310 	if (!ext4_emergency_state(sb) && !sb_rdonly(sb)) {
1311 		if (!aborted) {
1312 			ext4_clear_feature_journal_needs_recovery(sb);
1313 			ext4_clear_feature_orphan_present(sb);
1314 			es->s_state = cpu_to_le16(sbi->s_mount_state);
1315 		}
1316 		ext4_commit_super(sb);
1317 	}
1318 
1319 	ext4_group_desc_free(sbi);
1320 	ext4_flex_groups_free(sbi);
1321 
1322 	WARN_ON_ONCE(!(sbi->s_mount_state & EXT4_ERROR_FS) &&
1323 		     percpu_counter_sum(&sbi->s_dirtyclusters_counter));
1324 	ext4_percpu_param_destroy(sbi);
1325 #ifdef CONFIG_QUOTA
1326 	for (int i = 0; i < EXT4_MAXQUOTAS; i++)
1327 		kfree(get_qf_name(sb, sbi, i));
1328 #endif
1329 
1330 	/* Debugging code just in case the in-memory inode orphan list
1331 	 * isn't empty.  The on-disk one can be non-empty if we've
1332 	 * detected an error and taken the fs readonly, but the
1333 	 * in-memory list had better be clean by this point. */
1334 	if (!list_empty(&sbi->s_orphan))
1335 		dump_orphan_list(sb, sbi);
1336 	ASSERT(list_empty(&sbi->s_orphan));
1337 
1338 	sync_blockdev(sb->s_bdev);
1339 	invalidate_bdev(sb->s_bdev);
1340 	if (sbi->s_journal_bdev_file) {
1341 		/*
1342 		 * Invalidate the journal device's buffers.  We don't want them
1343 		 * floating about in memory - the physical journal device may
1344 		 * hotswapped, and it breaks the `ro-after' testing code.
1345 		 */
1346 		sync_blockdev(file_bdev(sbi->s_journal_bdev_file));
1347 		invalidate_bdev(file_bdev(sbi->s_journal_bdev_file));
1348 	}
1349 
1350 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1351 	sbi->s_ea_inode_cache = NULL;
1352 
1353 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1354 	sbi->s_ea_block_cache = NULL;
1355 
1356 	ext4_stop_mmpd(sbi);
1357 
1358 	brelse(sbi->s_sbh);
1359 	sb->s_fs_info = NULL;
1360 	/*
1361 	 * Now that we are completely done shutting down the
1362 	 * superblock, we need to actually destroy the kobject.
1363 	 */
1364 	kobject_put(&sbi->s_kobj);
1365 	wait_for_completion(&sbi->s_kobj_unregister);
1366 	kfree(sbi->s_blockgroup_lock);
1367 	fs_put_dax(sbi->s_daxdev, NULL);
1368 	fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1369 #if IS_ENABLED(CONFIG_UNICODE)
1370 	utf8_unload(sb->s_encoding);
1371 #endif
1372 	kfree(sbi);
1373 }
1374 
1375 static struct kmem_cache *ext4_inode_cachep;
1376 
1377 /*
1378  * Called inside transaction, so use GFP_NOFS
1379  */
1380 static struct inode *ext4_alloc_inode(struct super_block *sb)
1381 {
1382 	struct ext4_inode_info *ei;
1383 
1384 	ei = alloc_inode_sb(sb, ext4_inode_cachep, GFP_NOFS);
1385 	if (!ei)
1386 		return NULL;
1387 
1388 	inode_set_iversion(&ei->vfs_inode, 1);
1389 	ei->i_flags = 0;
1390 	spin_lock_init(&ei->i_raw_lock);
1391 	ei->i_prealloc_node = RB_ROOT;
1392 	atomic_set(&ei->i_prealloc_active, 0);
1393 	rwlock_init(&ei->i_prealloc_lock);
1394 	ext4_es_init_tree(&ei->i_es_tree);
1395 	rwlock_init(&ei->i_es_lock);
1396 	INIT_LIST_HEAD(&ei->i_es_list);
1397 	ei->i_es_all_nr = 0;
1398 	ei->i_es_shk_nr = 0;
1399 	ei->i_es_shrink_lblk = 0;
1400 	ei->i_reserved_data_blocks = 0;
1401 	spin_lock_init(&(ei->i_block_reservation_lock));
1402 	ext4_init_pending_tree(&ei->i_pending_tree);
1403 #ifdef CONFIG_QUOTA
1404 	ei->i_reserved_quota = 0;
1405 	memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1406 #endif
1407 	ei->jinode = NULL;
1408 	INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1409 	spin_lock_init(&ei->i_completed_io_lock);
1410 	ei->i_sync_tid = 0;
1411 	ei->i_datasync_tid = 0;
1412 	INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1413 	ext4_fc_init_inode(&ei->vfs_inode);
1414 	spin_lock_init(&ei->i_fc_lock);
1415 	return &ei->vfs_inode;
1416 }
1417 
1418 static int ext4_drop_inode(struct inode *inode)
1419 {
1420 	int drop = inode_generic_drop(inode);
1421 
1422 	if (!drop)
1423 		drop = fscrypt_drop_inode(inode);
1424 
1425 	trace_ext4_drop_inode(inode, drop);
1426 	return drop;
1427 }
1428 
1429 static void ext4_free_in_core_inode(struct inode *inode)
1430 {
1431 	fscrypt_free_inode(inode);
1432 	if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1433 		pr_warn("%s: inode %ld still in fc list",
1434 			__func__, inode->i_ino);
1435 	}
1436 	kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1437 }
1438 
1439 static void ext4_destroy_inode(struct inode *inode)
1440 {
1441 	if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1442 		ext4_msg(inode->i_sb, KERN_ERR,
1443 			 "Inode %lu (%p): orphan list check failed!",
1444 			 inode->i_ino, EXT4_I(inode));
1445 		print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1446 				EXT4_I(inode), sizeof(struct ext4_inode_info),
1447 				true);
1448 		dump_stack();
1449 	}
1450 
1451 	if (!(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ERROR_FS) &&
1452 	    WARN_ON_ONCE(EXT4_I(inode)->i_reserved_data_blocks))
1453 		ext4_msg(inode->i_sb, KERN_ERR,
1454 			 "Inode %lu (%p): i_reserved_data_blocks (%u) not cleared!",
1455 			 inode->i_ino, EXT4_I(inode),
1456 			 EXT4_I(inode)->i_reserved_data_blocks);
1457 }
1458 
1459 static void ext4_shutdown(struct super_block *sb)
1460 {
1461        ext4_force_shutdown(sb, EXT4_GOING_FLAGS_NOLOGFLUSH);
1462 }
1463 
1464 static void init_once(void *foo)
1465 {
1466 	struct ext4_inode_info *ei = foo;
1467 
1468 	INIT_LIST_HEAD(&ei->i_orphan);
1469 	init_rwsem(&ei->xattr_sem);
1470 	init_rwsem(&ei->i_data_sem);
1471 	inode_init_once(&ei->vfs_inode);
1472 	ext4_fc_init_inode(&ei->vfs_inode);
1473 #ifdef CONFIG_FS_ENCRYPTION
1474 	ei->i_crypt_info = NULL;
1475 #endif
1476 #ifdef CONFIG_FS_VERITY
1477 	ei->i_verity_info = NULL;
1478 #endif
1479 }
1480 
1481 static int __init init_inodecache(void)
1482 {
1483 	ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1484 				sizeof(struct ext4_inode_info), 0,
1485 				SLAB_RECLAIM_ACCOUNT | SLAB_ACCOUNT,
1486 				offsetof(struct ext4_inode_info, i_data),
1487 				sizeof_field(struct ext4_inode_info, i_data),
1488 				init_once);
1489 	if (ext4_inode_cachep == NULL)
1490 		return -ENOMEM;
1491 	return 0;
1492 }
1493 
1494 static void destroy_inodecache(void)
1495 {
1496 	/*
1497 	 * Make sure all delayed rcu free inodes are flushed before we
1498 	 * destroy cache.
1499 	 */
1500 	rcu_barrier();
1501 	kmem_cache_destroy(ext4_inode_cachep);
1502 }
1503 
1504 void ext4_clear_inode(struct inode *inode)
1505 {
1506 	ext4_fc_del(inode);
1507 	invalidate_inode_buffers(inode);
1508 	clear_inode(inode);
1509 	ext4_discard_preallocations(inode);
1510 	ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1511 	dquot_drop(inode);
1512 	if (EXT4_I(inode)->jinode) {
1513 		jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1514 					       EXT4_I(inode)->jinode);
1515 		jbd2_free_inode(EXT4_I(inode)->jinode);
1516 		EXT4_I(inode)->jinode = NULL;
1517 	}
1518 	fscrypt_put_encryption_info(inode);
1519 	fsverity_cleanup_inode(inode);
1520 }
1521 
1522 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1523 					u64 ino, u32 generation)
1524 {
1525 	struct inode *inode;
1526 
1527 	/*
1528 	 * Currently we don't know the generation for parent directory, so
1529 	 * a generation of 0 means "accept any"
1530 	 */
1531 	inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1532 	if (IS_ERR(inode))
1533 		return ERR_CAST(inode);
1534 	if (generation && inode->i_generation != generation) {
1535 		iput(inode);
1536 		return ERR_PTR(-ESTALE);
1537 	}
1538 
1539 	return inode;
1540 }
1541 
1542 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1543 					int fh_len, int fh_type)
1544 {
1545 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1546 				    ext4_nfs_get_inode);
1547 }
1548 
1549 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1550 					int fh_len, int fh_type)
1551 {
1552 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1553 				    ext4_nfs_get_inode);
1554 }
1555 
1556 static int ext4_nfs_commit_metadata(struct inode *inode)
1557 {
1558 	struct writeback_control wbc = {
1559 		.sync_mode = WB_SYNC_ALL
1560 	};
1561 
1562 	trace_ext4_nfs_commit_metadata(inode);
1563 	return ext4_write_inode(inode, &wbc);
1564 }
1565 
1566 #ifdef CONFIG_QUOTA
1567 static const char * const quotatypes[] = INITQFNAMES;
1568 #define QTYPE2NAME(t) (quotatypes[t])
1569 
1570 static int ext4_write_dquot(struct dquot *dquot);
1571 static int ext4_acquire_dquot(struct dquot *dquot);
1572 static int ext4_release_dquot(struct dquot *dquot);
1573 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1574 static int ext4_write_info(struct super_block *sb, int type);
1575 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1576 			 const struct path *path);
1577 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1578 			       size_t len, loff_t off);
1579 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1580 				const char *data, size_t len, loff_t off);
1581 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1582 			     unsigned int flags);
1583 
1584 static struct dquot __rcu **ext4_get_dquots(struct inode *inode)
1585 {
1586 	return EXT4_I(inode)->i_dquot;
1587 }
1588 
1589 static const struct dquot_operations ext4_quota_operations = {
1590 	.get_reserved_space	= ext4_get_reserved_space,
1591 	.write_dquot		= ext4_write_dquot,
1592 	.acquire_dquot		= ext4_acquire_dquot,
1593 	.release_dquot		= ext4_release_dquot,
1594 	.mark_dirty		= ext4_mark_dquot_dirty,
1595 	.write_info		= ext4_write_info,
1596 	.alloc_dquot		= dquot_alloc,
1597 	.destroy_dquot		= dquot_destroy,
1598 	.get_projid		= ext4_get_projid,
1599 	.get_inode_usage	= ext4_get_inode_usage,
1600 	.get_next_id		= dquot_get_next_id,
1601 };
1602 
1603 static const struct quotactl_ops ext4_qctl_operations = {
1604 	.quota_on	= ext4_quota_on,
1605 	.quota_off	= ext4_quota_off,
1606 	.quota_sync	= dquot_quota_sync,
1607 	.get_state	= dquot_get_state,
1608 	.set_info	= dquot_set_dqinfo,
1609 	.get_dqblk	= dquot_get_dqblk,
1610 	.set_dqblk	= dquot_set_dqblk,
1611 	.get_nextdqblk	= dquot_get_next_dqblk,
1612 };
1613 #endif
1614 
1615 static const struct super_operations ext4_sops = {
1616 	.alloc_inode	= ext4_alloc_inode,
1617 	.free_inode	= ext4_free_in_core_inode,
1618 	.destroy_inode	= ext4_destroy_inode,
1619 	.write_inode	= ext4_write_inode,
1620 	.dirty_inode	= ext4_dirty_inode,
1621 	.drop_inode	= ext4_drop_inode,
1622 	.evict_inode	= ext4_evict_inode,
1623 	.put_super	= ext4_put_super,
1624 	.sync_fs	= ext4_sync_fs,
1625 	.freeze_fs	= ext4_freeze,
1626 	.unfreeze_fs	= ext4_unfreeze,
1627 	.statfs		= ext4_statfs,
1628 	.show_options	= ext4_show_options,
1629 	.shutdown	= ext4_shutdown,
1630 #ifdef CONFIG_QUOTA
1631 	.quota_read	= ext4_quota_read,
1632 	.quota_write	= ext4_quota_write,
1633 	.get_dquots	= ext4_get_dquots,
1634 #endif
1635 };
1636 
1637 static const struct export_operations ext4_export_ops = {
1638 	.encode_fh = generic_encode_ino32_fh,
1639 	.fh_to_dentry = ext4_fh_to_dentry,
1640 	.fh_to_parent = ext4_fh_to_parent,
1641 	.get_parent = ext4_get_parent,
1642 	.commit_metadata = ext4_nfs_commit_metadata,
1643 };
1644 
1645 enum {
1646 	Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1647 	Opt_resgid, Opt_resuid, Opt_sb,
1648 	Opt_nouid32, Opt_debug, Opt_removed,
1649 	Opt_user_xattr, Opt_acl,
1650 	Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1651 	Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1652 	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1653 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1654 	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1655 	Opt_inlinecrypt,
1656 	Opt_usrjquota, Opt_grpjquota, Opt_quota,
1657 	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1658 	Opt_usrquota, Opt_grpquota, Opt_prjquota,
1659 	Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1660 	Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1661 	Opt_nowarn_on_error, Opt_mblk_io_submit, Opt_debug_want_extra_isize,
1662 	Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1663 	Opt_inode_readahead_blks, Opt_journal_ioprio,
1664 	Opt_dioread_nolock, Opt_dioread_lock,
1665 	Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1666 	Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1667 	Opt_no_prefetch_block_bitmaps, Opt_mb_optimize_scan,
1668 	Opt_errors, Opt_data, Opt_data_err, Opt_jqfmt, Opt_dax_type,
1669 #ifdef CONFIG_EXT4_DEBUG
1670 	Opt_fc_debug_max_replay, Opt_fc_debug_force
1671 #endif
1672 };
1673 
1674 static const struct constant_table ext4_param_errors[] = {
1675 	{"continue",	EXT4_MOUNT_ERRORS_CONT},
1676 	{"panic",	EXT4_MOUNT_ERRORS_PANIC},
1677 	{"remount-ro",	EXT4_MOUNT_ERRORS_RO},
1678 	{}
1679 };
1680 
1681 static const struct constant_table ext4_param_data[] = {
1682 	{"journal",	EXT4_MOUNT_JOURNAL_DATA},
1683 	{"ordered",	EXT4_MOUNT_ORDERED_DATA},
1684 	{"writeback",	EXT4_MOUNT_WRITEBACK_DATA},
1685 	{}
1686 };
1687 
1688 static const struct constant_table ext4_param_data_err[] = {
1689 	{"abort",	Opt_data_err_abort},
1690 	{"ignore",	Opt_data_err_ignore},
1691 	{}
1692 };
1693 
1694 static const struct constant_table ext4_param_jqfmt[] = {
1695 	{"vfsold",	QFMT_VFS_OLD},
1696 	{"vfsv0",	QFMT_VFS_V0},
1697 	{"vfsv1",	QFMT_VFS_V1},
1698 	{}
1699 };
1700 
1701 static const struct constant_table ext4_param_dax[] = {
1702 	{"always",	Opt_dax_always},
1703 	{"inode",	Opt_dax_inode},
1704 	{"never",	Opt_dax_never},
1705 	{}
1706 };
1707 
1708 /*
1709  * Mount option specification
1710  * We don't use fsparam_flag_no because of the way we set the
1711  * options and the way we show them in _ext4_show_options(). To
1712  * keep the changes to a minimum, let's keep the negative options
1713  * separate for now.
1714  */
1715 static const struct fs_parameter_spec ext4_param_specs[] = {
1716 	fsparam_flag	("bsddf",		Opt_bsd_df),
1717 	fsparam_flag	("minixdf",		Opt_minix_df),
1718 	fsparam_flag	("grpid",		Opt_grpid),
1719 	fsparam_flag	("bsdgroups",		Opt_grpid),
1720 	fsparam_flag	("nogrpid",		Opt_nogrpid),
1721 	fsparam_flag	("sysvgroups",		Opt_nogrpid),
1722 	fsparam_gid	("resgid",		Opt_resgid),
1723 	fsparam_uid	("resuid",		Opt_resuid),
1724 	fsparam_u32	("sb",			Opt_sb),
1725 	fsparam_enum	("errors",		Opt_errors, ext4_param_errors),
1726 	fsparam_flag	("nouid32",		Opt_nouid32),
1727 	fsparam_flag	("debug",		Opt_debug),
1728 	fsparam_flag	("oldalloc",		Opt_removed),
1729 	fsparam_flag	("orlov",		Opt_removed),
1730 	fsparam_flag	("user_xattr",		Opt_user_xattr),
1731 	fsparam_flag	("acl",			Opt_acl),
1732 	fsparam_flag	("norecovery",		Opt_noload),
1733 	fsparam_flag	("noload",		Opt_noload),
1734 	fsparam_flag	("bh",			Opt_removed),
1735 	fsparam_flag	("nobh",		Opt_removed),
1736 	fsparam_u32	("commit",		Opt_commit),
1737 	fsparam_u32	("min_batch_time",	Opt_min_batch_time),
1738 	fsparam_u32	("max_batch_time",	Opt_max_batch_time),
1739 	fsparam_u32	("journal_dev",		Opt_journal_dev),
1740 	fsparam_bdev	("journal_path",	Opt_journal_path),
1741 	fsparam_flag	("journal_checksum",	Opt_journal_checksum),
1742 	fsparam_flag	("nojournal_checksum",	Opt_nojournal_checksum),
1743 	fsparam_flag	("journal_async_commit",Opt_journal_async_commit),
1744 	fsparam_flag	("abort",		Opt_abort),
1745 	fsparam_enum	("data",		Opt_data, ext4_param_data),
1746 	fsparam_enum	("data_err",		Opt_data_err,
1747 						ext4_param_data_err),
1748 	fsparam_string_empty
1749 			("usrjquota",		Opt_usrjquota),
1750 	fsparam_string_empty
1751 			("grpjquota",		Opt_grpjquota),
1752 	fsparam_enum	("jqfmt",		Opt_jqfmt, ext4_param_jqfmt),
1753 	fsparam_flag	("grpquota",		Opt_grpquota),
1754 	fsparam_flag	("quota",		Opt_quota),
1755 	fsparam_flag	("noquota",		Opt_noquota),
1756 	fsparam_flag	("usrquota",		Opt_usrquota),
1757 	fsparam_flag	("prjquota",		Opt_prjquota),
1758 	fsparam_flag	("barrier",		Opt_barrier),
1759 	fsparam_u32	("barrier",		Opt_barrier),
1760 	fsparam_flag	("nobarrier",		Opt_nobarrier),
1761 	fsparam_flag	("i_version",		Opt_removed),
1762 	fsparam_flag	("dax",			Opt_dax),
1763 	fsparam_enum	("dax",			Opt_dax_type, ext4_param_dax),
1764 	fsparam_u32	("stripe",		Opt_stripe),
1765 	fsparam_flag	("delalloc",		Opt_delalloc),
1766 	fsparam_flag	("nodelalloc",		Opt_nodelalloc),
1767 	fsparam_flag	("warn_on_error",	Opt_warn_on_error),
1768 	fsparam_flag	("nowarn_on_error",	Opt_nowarn_on_error),
1769 	fsparam_u32	("debug_want_extra_isize",
1770 						Opt_debug_want_extra_isize),
1771 	fsparam_flag	("mblk_io_submit",	Opt_removed),
1772 	fsparam_flag	("nomblk_io_submit",	Opt_removed),
1773 	fsparam_flag	("block_validity",	Opt_block_validity),
1774 	fsparam_flag	("noblock_validity",	Opt_noblock_validity),
1775 	fsparam_u32	("inode_readahead_blks",
1776 						Opt_inode_readahead_blks),
1777 	fsparam_u32	("journal_ioprio",	Opt_journal_ioprio),
1778 	fsparam_u32	("auto_da_alloc",	Opt_auto_da_alloc),
1779 	fsparam_flag	("auto_da_alloc",	Opt_auto_da_alloc),
1780 	fsparam_flag	("noauto_da_alloc",	Opt_noauto_da_alloc),
1781 	fsparam_flag	("dioread_nolock",	Opt_dioread_nolock),
1782 	fsparam_flag	("nodioread_nolock",	Opt_dioread_lock),
1783 	fsparam_flag	("dioread_lock",	Opt_dioread_lock),
1784 	fsparam_flag	("discard",		Opt_discard),
1785 	fsparam_flag	("nodiscard",		Opt_nodiscard),
1786 	fsparam_u32	("init_itable",		Opt_init_itable),
1787 	fsparam_flag	("init_itable",		Opt_init_itable),
1788 	fsparam_flag	("noinit_itable",	Opt_noinit_itable),
1789 #ifdef CONFIG_EXT4_DEBUG
1790 	fsparam_flag	("fc_debug_force",	Opt_fc_debug_force),
1791 	fsparam_u32	("fc_debug_max_replay",	Opt_fc_debug_max_replay),
1792 #endif
1793 	fsparam_u32	("max_dir_size_kb",	Opt_max_dir_size_kb),
1794 	fsparam_flag	("test_dummy_encryption",
1795 						Opt_test_dummy_encryption),
1796 	fsparam_string	("test_dummy_encryption",
1797 						Opt_test_dummy_encryption),
1798 	fsparam_flag	("inlinecrypt",		Opt_inlinecrypt),
1799 	fsparam_flag	("nombcache",		Opt_nombcache),
1800 	fsparam_flag	("no_mbcache",		Opt_nombcache),	/* for backward compatibility */
1801 	fsparam_flag	("prefetch_block_bitmaps",
1802 						Opt_removed),
1803 	fsparam_flag	("no_prefetch_block_bitmaps",
1804 						Opt_no_prefetch_block_bitmaps),
1805 	fsparam_s32	("mb_optimize_scan",	Opt_mb_optimize_scan),
1806 	fsparam_string	("check",		Opt_removed),	/* mount option from ext2/3 */
1807 	fsparam_flag	("nocheck",		Opt_removed),	/* mount option from ext2/3 */
1808 	fsparam_flag	("reservation",		Opt_removed),	/* mount option from ext2/3 */
1809 	fsparam_flag	("noreservation",	Opt_removed),	/* mount option from ext2/3 */
1810 	fsparam_u32	("journal",		Opt_removed),	/* mount option from ext2/3 */
1811 	{}
1812 };
1813 
1814 
1815 #define MOPT_SET	0x0001
1816 #define MOPT_CLEAR	0x0002
1817 #define MOPT_NOSUPPORT	0x0004
1818 #define MOPT_EXPLICIT	0x0008
1819 #ifdef CONFIG_QUOTA
1820 #define MOPT_Q		0
1821 #define MOPT_QFMT	0x0010
1822 #else
1823 #define MOPT_Q		MOPT_NOSUPPORT
1824 #define MOPT_QFMT	MOPT_NOSUPPORT
1825 #endif
1826 #define MOPT_NO_EXT2	0x0020
1827 #define MOPT_NO_EXT3	0x0040
1828 #define MOPT_EXT4_ONLY	(MOPT_NO_EXT2 | MOPT_NO_EXT3)
1829 #define MOPT_SKIP	0x0080
1830 #define	MOPT_2		0x0100
1831 
1832 static const struct mount_opts {
1833 	int	token;
1834 	int	mount_opt;
1835 	int	flags;
1836 } ext4_mount_opts[] = {
1837 	{Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1838 	{Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1839 	{Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1840 	{Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1841 	{Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1842 	{Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1843 	{Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1844 	 MOPT_EXT4_ONLY | MOPT_SET},
1845 	{Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1846 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1847 	{Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1848 	{Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1849 	{Opt_delalloc, EXT4_MOUNT_DELALLOC,
1850 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1851 	{Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1852 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1853 	{Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1854 	{Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1855 	{Opt_commit, 0, MOPT_NO_EXT2},
1856 	{Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1857 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1858 	{Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1859 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1860 	{Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1861 				    EXT4_MOUNT_JOURNAL_CHECKSUM),
1862 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1863 	{Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1864 	{Opt_data_err, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_NO_EXT2},
1865 	{Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1866 	{Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1867 	{Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1868 	{Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1869 	{Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1870 	{Opt_dax_type, 0, MOPT_EXT4_ONLY},
1871 	{Opt_journal_dev, 0, MOPT_NO_EXT2},
1872 	{Opt_journal_path, 0, MOPT_NO_EXT2},
1873 	{Opt_journal_ioprio, 0, MOPT_NO_EXT2},
1874 	{Opt_data, 0, MOPT_NO_EXT2},
1875 	{Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1876 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1877 	{Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1878 #else
1879 	{Opt_acl, 0, MOPT_NOSUPPORT},
1880 #endif
1881 	{Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1882 	{Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1883 	{Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1884 	{Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1885 							MOPT_SET | MOPT_Q},
1886 	{Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1887 							MOPT_SET | MOPT_Q},
1888 	{Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1889 							MOPT_SET | MOPT_Q},
1890 	{Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1891 		       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1892 							MOPT_CLEAR | MOPT_Q},
1893 	{Opt_usrjquota, 0, MOPT_Q},
1894 	{Opt_grpjquota, 0, MOPT_Q},
1895 	{Opt_jqfmt, 0, MOPT_QFMT},
1896 	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1897 	{Opt_no_prefetch_block_bitmaps, EXT4_MOUNT_NO_PREFETCH_BLOCK_BITMAPS,
1898 	 MOPT_SET},
1899 #ifdef CONFIG_EXT4_DEBUG
1900 	{Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
1901 	 MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
1902 #endif
1903 	{Opt_abort, EXT4_MOUNT2_ABORT, MOPT_SET | MOPT_2},
1904 	{Opt_err, 0, 0}
1905 };
1906 
1907 #if IS_ENABLED(CONFIG_UNICODE)
1908 static const struct ext4_sb_encodings {
1909 	__u16 magic;
1910 	char *name;
1911 	unsigned int version;
1912 } ext4_sb_encoding_map[] = {
1913 	{EXT4_ENC_UTF8_12_1, "utf8", UNICODE_AGE(12, 1, 0)},
1914 };
1915 
1916 static const struct ext4_sb_encodings *
1917 ext4_sb_read_encoding(const struct ext4_super_block *es)
1918 {
1919 	__u16 magic = le16_to_cpu(es->s_encoding);
1920 	int i;
1921 
1922 	for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1923 		if (magic == ext4_sb_encoding_map[i].magic)
1924 			return &ext4_sb_encoding_map[i];
1925 
1926 	return NULL;
1927 }
1928 #endif
1929 
1930 #define EXT4_SPEC_JQUOTA			(1 <<  0)
1931 #define EXT4_SPEC_JQFMT				(1 <<  1)
1932 #define EXT4_SPEC_DATAJ				(1 <<  2)
1933 #define EXT4_SPEC_SB_BLOCK			(1 <<  3)
1934 #define EXT4_SPEC_JOURNAL_DEV			(1 <<  4)
1935 #define EXT4_SPEC_JOURNAL_IOPRIO		(1 <<  5)
1936 #define EXT4_SPEC_s_want_extra_isize		(1 <<  7)
1937 #define EXT4_SPEC_s_max_batch_time		(1 <<  8)
1938 #define EXT4_SPEC_s_min_batch_time		(1 <<  9)
1939 #define EXT4_SPEC_s_inode_readahead_blks	(1 << 10)
1940 #define EXT4_SPEC_s_li_wait_mult		(1 << 11)
1941 #define EXT4_SPEC_s_max_dir_size_kb		(1 << 12)
1942 #define EXT4_SPEC_s_stripe			(1 << 13)
1943 #define EXT4_SPEC_s_resuid			(1 << 14)
1944 #define EXT4_SPEC_s_resgid			(1 << 15)
1945 #define EXT4_SPEC_s_commit_interval		(1 << 16)
1946 #define EXT4_SPEC_s_fc_debug_max_replay		(1 << 17)
1947 #define EXT4_SPEC_s_sb_block			(1 << 18)
1948 #define EXT4_SPEC_mb_optimize_scan		(1 << 19)
1949 
1950 struct ext4_fs_context {
1951 	char		*s_qf_names[EXT4_MAXQUOTAS];
1952 	struct fscrypt_dummy_policy dummy_enc_policy;
1953 	int		s_jquota_fmt;	/* Format of quota to use */
1954 #ifdef CONFIG_EXT4_DEBUG
1955 	int s_fc_debug_max_replay;
1956 #endif
1957 	unsigned short	qname_spec;
1958 	unsigned long	vals_s_flags;	/* Bits to set in s_flags */
1959 	unsigned long	mask_s_flags;	/* Bits changed in s_flags */
1960 	unsigned long	journal_devnum;
1961 	unsigned long	s_commit_interval;
1962 	unsigned long	s_stripe;
1963 	unsigned int	s_inode_readahead_blks;
1964 	unsigned int	s_want_extra_isize;
1965 	unsigned int	s_li_wait_mult;
1966 	unsigned int	s_max_dir_size_kb;
1967 	unsigned int	journal_ioprio;
1968 	unsigned int	vals_s_mount_opt;
1969 	unsigned int	mask_s_mount_opt;
1970 	unsigned int	vals_s_mount_opt2;
1971 	unsigned int	mask_s_mount_opt2;
1972 	unsigned int	opt_flags;	/* MOPT flags */
1973 	unsigned int	spec;
1974 	u32		s_max_batch_time;
1975 	u32		s_min_batch_time;
1976 	kuid_t		s_resuid;
1977 	kgid_t		s_resgid;
1978 	ext4_fsblk_t	s_sb_block;
1979 };
1980 
1981 static void ext4_fc_free(struct fs_context *fc)
1982 {
1983 	struct ext4_fs_context *ctx = fc->fs_private;
1984 	int i;
1985 
1986 	if (!ctx)
1987 		return;
1988 
1989 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
1990 		kfree(ctx->s_qf_names[i]);
1991 
1992 	fscrypt_free_dummy_policy(&ctx->dummy_enc_policy);
1993 	kfree(ctx);
1994 }
1995 
1996 int ext4_init_fs_context(struct fs_context *fc)
1997 {
1998 	struct ext4_fs_context *ctx;
1999 
2000 	ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2001 	if (!ctx)
2002 		return -ENOMEM;
2003 
2004 	fc->fs_private = ctx;
2005 	fc->ops = &ext4_context_ops;
2006 
2007 	/* i_version is always enabled now */
2008 	fc->sb_flags |= SB_I_VERSION;
2009 
2010 	return 0;
2011 }
2012 
2013 #ifdef CONFIG_QUOTA
2014 /*
2015  * Note the name of the specified quota file.
2016  */
2017 static int note_qf_name(struct fs_context *fc, int qtype,
2018 		       struct fs_parameter *param)
2019 {
2020 	struct ext4_fs_context *ctx = fc->fs_private;
2021 	char *qname;
2022 
2023 	if (param->size < 1) {
2024 		ext4_msg(NULL, KERN_ERR, "Missing quota name");
2025 		return -EINVAL;
2026 	}
2027 	if (strchr(param->string, '/')) {
2028 		ext4_msg(NULL, KERN_ERR,
2029 			 "quotafile must be on filesystem root");
2030 		return -EINVAL;
2031 	}
2032 	if (ctx->s_qf_names[qtype]) {
2033 		if (strcmp(ctx->s_qf_names[qtype], param->string) != 0) {
2034 			ext4_msg(NULL, KERN_ERR,
2035 				 "%s quota file already specified",
2036 				 QTYPE2NAME(qtype));
2037 			return -EINVAL;
2038 		}
2039 		return 0;
2040 	}
2041 
2042 	qname = kmemdup_nul(param->string, param->size, GFP_KERNEL);
2043 	if (!qname) {
2044 		ext4_msg(NULL, KERN_ERR,
2045 			 "Not enough memory for storing quotafile name");
2046 		return -ENOMEM;
2047 	}
2048 	ctx->s_qf_names[qtype] = qname;
2049 	ctx->qname_spec |= 1 << qtype;
2050 	ctx->spec |= EXT4_SPEC_JQUOTA;
2051 	return 0;
2052 }
2053 
2054 /*
2055  * Clear the name of the specified quota file.
2056  */
2057 static int unnote_qf_name(struct fs_context *fc, int qtype)
2058 {
2059 	struct ext4_fs_context *ctx = fc->fs_private;
2060 
2061 	kfree(ctx->s_qf_names[qtype]);
2062 
2063 	ctx->s_qf_names[qtype] = NULL;
2064 	ctx->qname_spec |= 1 << qtype;
2065 	ctx->spec |= EXT4_SPEC_JQUOTA;
2066 	return 0;
2067 }
2068 #endif
2069 
2070 static int ext4_parse_test_dummy_encryption(const struct fs_parameter *param,
2071 					    struct ext4_fs_context *ctx)
2072 {
2073 	int err;
2074 
2075 	if (!IS_ENABLED(CONFIG_FS_ENCRYPTION)) {
2076 		ext4_msg(NULL, KERN_WARNING,
2077 			 "test_dummy_encryption option not supported");
2078 		return -EINVAL;
2079 	}
2080 	err = fscrypt_parse_test_dummy_encryption(param,
2081 						  &ctx->dummy_enc_policy);
2082 	if (err == -EINVAL) {
2083 		ext4_msg(NULL, KERN_WARNING,
2084 			 "Value of option \"%s\" is unrecognized", param->key);
2085 	} else if (err == -EEXIST) {
2086 		ext4_msg(NULL, KERN_WARNING,
2087 			 "Conflicting test_dummy_encryption options");
2088 		return -EINVAL;
2089 	}
2090 	return err;
2091 }
2092 
2093 #define EXT4_SET_CTX(name)						\
2094 static inline __maybe_unused						\
2095 void ctx_set_##name(struct ext4_fs_context *ctx, unsigned long flag)	\
2096 {									\
2097 	ctx->mask_s_##name |= flag;					\
2098 	ctx->vals_s_##name |= flag;					\
2099 }
2100 
2101 #define EXT4_CLEAR_CTX(name)						\
2102 static inline __maybe_unused						\
2103 void ctx_clear_##name(struct ext4_fs_context *ctx, unsigned long flag)	\
2104 {									\
2105 	ctx->mask_s_##name |= flag;					\
2106 	ctx->vals_s_##name &= ~flag;					\
2107 }
2108 
2109 #define EXT4_TEST_CTX(name)						\
2110 static inline unsigned long						\
2111 ctx_test_##name(struct ext4_fs_context *ctx, unsigned long flag)	\
2112 {									\
2113 	return (ctx->vals_s_##name & flag);				\
2114 }
2115 
2116 EXT4_SET_CTX(flags); /* set only */
2117 EXT4_SET_CTX(mount_opt);
2118 EXT4_CLEAR_CTX(mount_opt);
2119 EXT4_TEST_CTX(mount_opt);
2120 EXT4_SET_CTX(mount_opt2);
2121 EXT4_CLEAR_CTX(mount_opt2);
2122 EXT4_TEST_CTX(mount_opt2);
2123 
2124 static int ext4_parse_param(struct fs_context *fc, struct fs_parameter *param)
2125 {
2126 	struct ext4_fs_context *ctx = fc->fs_private;
2127 	struct fs_parse_result result;
2128 	const struct mount_opts *m;
2129 	int is_remount;
2130 	int token;
2131 
2132 	token = fs_parse(fc, ext4_param_specs, param, &result);
2133 	if (token < 0)
2134 		return token;
2135 	is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2136 
2137 	for (m = ext4_mount_opts; m->token != Opt_err; m++)
2138 		if (token == m->token)
2139 			break;
2140 
2141 	ctx->opt_flags |= m->flags;
2142 
2143 	if (m->flags & MOPT_EXPLICIT) {
2144 		if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2145 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_EXPLICIT_DELALLOC);
2146 		} else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2147 			ctx_set_mount_opt2(ctx,
2148 				       EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM);
2149 		} else
2150 			return -EINVAL;
2151 	}
2152 
2153 	if (m->flags & MOPT_NOSUPPORT) {
2154 		ext4_msg(NULL, KERN_ERR, "%s option not supported",
2155 			 param->key);
2156 		return 0;
2157 	}
2158 
2159 	switch (token) {
2160 #ifdef CONFIG_QUOTA
2161 	case Opt_usrjquota:
2162 		if (!*param->string)
2163 			return unnote_qf_name(fc, USRQUOTA);
2164 		else
2165 			return note_qf_name(fc, USRQUOTA, param);
2166 	case Opt_grpjquota:
2167 		if (!*param->string)
2168 			return unnote_qf_name(fc, GRPQUOTA);
2169 		else
2170 			return note_qf_name(fc, GRPQUOTA, param);
2171 #endif
2172 	case Opt_sb:
2173 		if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2174 			ext4_msg(NULL, KERN_WARNING,
2175 				 "Ignoring %s option on remount", param->key);
2176 		} else {
2177 			ctx->s_sb_block = result.uint_32;
2178 			ctx->spec |= EXT4_SPEC_s_sb_block;
2179 		}
2180 		return 0;
2181 	case Opt_removed:
2182 		ext4_msg(NULL, KERN_WARNING, "Ignoring removed %s option",
2183 			 param->key);
2184 		return 0;
2185 	case Opt_inlinecrypt:
2186 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2187 		ctx_set_flags(ctx, SB_INLINECRYPT);
2188 #else
2189 		ext4_msg(NULL, KERN_ERR, "inline encryption not supported");
2190 #endif
2191 		return 0;
2192 	case Opt_errors:
2193 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_ERRORS_MASK);
2194 		ctx_set_mount_opt(ctx, result.uint_32);
2195 		return 0;
2196 #ifdef CONFIG_QUOTA
2197 	case Opt_jqfmt:
2198 		ctx->s_jquota_fmt = result.uint_32;
2199 		ctx->spec |= EXT4_SPEC_JQFMT;
2200 		return 0;
2201 #endif
2202 	case Opt_data:
2203 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2204 		ctx_set_mount_opt(ctx, result.uint_32);
2205 		ctx->spec |= EXT4_SPEC_DATAJ;
2206 		return 0;
2207 	case Opt_commit:
2208 		if (result.uint_32 == 0)
2209 			result.uint_32 = JBD2_DEFAULT_MAX_COMMIT_AGE;
2210 		else if (result.uint_32 > INT_MAX / HZ) {
2211 			ext4_msg(NULL, KERN_ERR,
2212 				 "Invalid commit interval %d, "
2213 				 "must be smaller than %d",
2214 				 result.uint_32, INT_MAX / HZ);
2215 			return -EINVAL;
2216 		}
2217 		ctx->s_commit_interval = HZ * result.uint_32;
2218 		ctx->spec |= EXT4_SPEC_s_commit_interval;
2219 		return 0;
2220 	case Opt_debug_want_extra_isize:
2221 		if ((result.uint_32 & 1) || (result.uint_32 < 4)) {
2222 			ext4_msg(NULL, KERN_ERR,
2223 				 "Invalid want_extra_isize %d", result.uint_32);
2224 			return -EINVAL;
2225 		}
2226 		ctx->s_want_extra_isize = result.uint_32;
2227 		ctx->spec |= EXT4_SPEC_s_want_extra_isize;
2228 		return 0;
2229 	case Opt_max_batch_time:
2230 		ctx->s_max_batch_time = result.uint_32;
2231 		ctx->spec |= EXT4_SPEC_s_max_batch_time;
2232 		return 0;
2233 	case Opt_min_batch_time:
2234 		ctx->s_min_batch_time = result.uint_32;
2235 		ctx->spec |= EXT4_SPEC_s_min_batch_time;
2236 		return 0;
2237 	case Opt_inode_readahead_blks:
2238 		if (result.uint_32 &&
2239 		    (result.uint_32 > (1 << 30) ||
2240 		     !is_power_of_2(result.uint_32))) {
2241 			ext4_msg(NULL, KERN_ERR,
2242 				 "EXT4-fs: inode_readahead_blks must be "
2243 				 "0 or a power of 2 smaller than 2^31");
2244 			return -EINVAL;
2245 		}
2246 		ctx->s_inode_readahead_blks = result.uint_32;
2247 		ctx->spec |= EXT4_SPEC_s_inode_readahead_blks;
2248 		return 0;
2249 	case Opt_init_itable:
2250 		ctx_set_mount_opt(ctx, EXT4_MOUNT_INIT_INODE_TABLE);
2251 		ctx->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
2252 		if (param->type == fs_value_is_string)
2253 			ctx->s_li_wait_mult = result.uint_32;
2254 		ctx->spec |= EXT4_SPEC_s_li_wait_mult;
2255 		return 0;
2256 	case Opt_max_dir_size_kb:
2257 		ctx->s_max_dir_size_kb = result.uint_32;
2258 		ctx->spec |= EXT4_SPEC_s_max_dir_size_kb;
2259 		return 0;
2260 #ifdef CONFIG_EXT4_DEBUG
2261 	case Opt_fc_debug_max_replay:
2262 		ctx->s_fc_debug_max_replay = result.uint_32;
2263 		ctx->spec |= EXT4_SPEC_s_fc_debug_max_replay;
2264 		return 0;
2265 #endif
2266 	case Opt_stripe:
2267 		ctx->s_stripe = result.uint_32;
2268 		ctx->spec |= EXT4_SPEC_s_stripe;
2269 		return 0;
2270 	case Opt_resuid:
2271 		ctx->s_resuid = result.uid;
2272 		ctx->spec |= EXT4_SPEC_s_resuid;
2273 		return 0;
2274 	case Opt_resgid:
2275 		ctx->s_resgid = result.gid;
2276 		ctx->spec |= EXT4_SPEC_s_resgid;
2277 		return 0;
2278 	case Opt_journal_dev:
2279 		if (is_remount) {
2280 			ext4_msg(NULL, KERN_ERR,
2281 				 "Cannot specify journal on remount");
2282 			return -EINVAL;
2283 		}
2284 		ctx->journal_devnum = result.uint_32;
2285 		ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2286 		return 0;
2287 	case Opt_journal_path:
2288 	{
2289 		struct inode *journal_inode;
2290 		struct path path;
2291 		int error;
2292 
2293 		if (is_remount) {
2294 			ext4_msg(NULL, KERN_ERR,
2295 				 "Cannot specify journal on remount");
2296 			return -EINVAL;
2297 		}
2298 
2299 		error = fs_lookup_param(fc, param, 1, LOOKUP_FOLLOW, &path);
2300 		if (error) {
2301 			ext4_msg(NULL, KERN_ERR, "error: could not find "
2302 				 "journal device path");
2303 			return -EINVAL;
2304 		}
2305 
2306 		journal_inode = d_inode(path.dentry);
2307 		ctx->journal_devnum = new_encode_dev(journal_inode->i_rdev);
2308 		ctx->spec |= EXT4_SPEC_JOURNAL_DEV;
2309 		path_put(&path);
2310 		return 0;
2311 	}
2312 	case Opt_journal_ioprio:
2313 		if (result.uint_32 > 7) {
2314 			ext4_msg(NULL, KERN_ERR, "Invalid journal IO priority"
2315 				 " (must be 0-7)");
2316 			return -EINVAL;
2317 		}
2318 		ctx->journal_ioprio =
2319 			IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, result.uint_32);
2320 		ctx->spec |= EXT4_SPEC_JOURNAL_IOPRIO;
2321 		return 0;
2322 	case Opt_test_dummy_encryption:
2323 		return ext4_parse_test_dummy_encryption(param, ctx);
2324 	case Opt_dax:
2325 	case Opt_dax_type:
2326 #ifdef CONFIG_FS_DAX
2327 	{
2328 		int type = (token == Opt_dax) ?
2329 			   Opt_dax : result.uint_32;
2330 
2331 		switch (type) {
2332 		case Opt_dax:
2333 		case Opt_dax_always:
2334 			ctx_set_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2335 			ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2336 			break;
2337 		case Opt_dax_never:
2338 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2339 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2340 			break;
2341 		case Opt_dax_inode:
2342 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS);
2343 			ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER);
2344 			/* Strictly for printing options */
2345 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE);
2346 			break;
2347 		}
2348 		return 0;
2349 	}
2350 #else
2351 		ext4_msg(NULL, KERN_INFO, "dax option not supported");
2352 		return -EINVAL;
2353 #endif
2354 	case Opt_data_err:
2355 		if (result.uint_32 == Opt_data_err_abort)
2356 			ctx_set_mount_opt(ctx, m->mount_opt);
2357 		else if (result.uint_32 == Opt_data_err_ignore)
2358 			ctx_clear_mount_opt(ctx, m->mount_opt);
2359 		return 0;
2360 	case Opt_mb_optimize_scan:
2361 		if (result.int_32 == 1) {
2362 			ctx_set_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2363 			ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2364 		} else if (result.int_32 == 0) {
2365 			ctx_clear_mount_opt2(ctx, EXT4_MOUNT2_MB_OPTIMIZE_SCAN);
2366 			ctx->spec |= EXT4_SPEC_mb_optimize_scan;
2367 		} else {
2368 			ext4_msg(NULL, KERN_WARNING,
2369 				 "mb_optimize_scan should be set to 0 or 1.");
2370 			return -EINVAL;
2371 		}
2372 		return 0;
2373 	}
2374 
2375 	/*
2376 	 * At this point we should only be getting options requiring MOPT_SET,
2377 	 * or MOPT_CLEAR. Anything else is a bug
2378 	 */
2379 	if (m->token == Opt_err) {
2380 		ext4_msg(NULL, KERN_WARNING, "buggy handling of option %s",
2381 			 param->key);
2382 		WARN_ON(1);
2383 		return -EINVAL;
2384 	}
2385 
2386 	else {
2387 		unsigned int set = 0;
2388 
2389 		if ((param->type == fs_value_is_flag) ||
2390 		    result.uint_32 > 0)
2391 			set = 1;
2392 
2393 		if (m->flags & MOPT_CLEAR)
2394 			set = !set;
2395 		else if (unlikely(!(m->flags & MOPT_SET))) {
2396 			ext4_msg(NULL, KERN_WARNING,
2397 				 "buggy handling of option %s",
2398 				 param->key);
2399 			WARN_ON(1);
2400 			return -EINVAL;
2401 		}
2402 		if (m->flags & MOPT_2) {
2403 			if (set != 0)
2404 				ctx_set_mount_opt2(ctx, m->mount_opt);
2405 			else
2406 				ctx_clear_mount_opt2(ctx, m->mount_opt);
2407 		} else {
2408 			if (set != 0)
2409 				ctx_set_mount_opt(ctx, m->mount_opt);
2410 			else
2411 				ctx_clear_mount_opt(ctx, m->mount_opt);
2412 		}
2413 	}
2414 
2415 	return 0;
2416 }
2417 
2418 static int parse_options(struct fs_context *fc, char *options)
2419 {
2420 	struct fs_parameter param;
2421 	int ret;
2422 	char *key;
2423 
2424 	if (!options)
2425 		return 0;
2426 
2427 	while ((key = strsep(&options, ",")) != NULL) {
2428 		if (*key) {
2429 			size_t v_len = 0;
2430 			char *value = strchr(key, '=');
2431 
2432 			param.type = fs_value_is_flag;
2433 			param.string = NULL;
2434 
2435 			if (value) {
2436 				if (value == key)
2437 					continue;
2438 
2439 				*value++ = 0;
2440 				v_len = strlen(value);
2441 				param.string = kmemdup_nul(value, v_len,
2442 							   GFP_KERNEL);
2443 				if (!param.string)
2444 					return -ENOMEM;
2445 				param.type = fs_value_is_string;
2446 			}
2447 
2448 			param.key = key;
2449 			param.size = v_len;
2450 
2451 			ret = ext4_parse_param(fc, &param);
2452 			kfree(param.string);
2453 			if (ret < 0)
2454 				return ret;
2455 		}
2456 	}
2457 
2458 	ret = ext4_validate_options(fc);
2459 	if (ret < 0)
2460 		return ret;
2461 
2462 	return 0;
2463 }
2464 
2465 static int parse_apply_sb_mount_options(struct super_block *sb,
2466 					struct ext4_fs_context *m_ctx)
2467 {
2468 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2469 	char *s_mount_opts = NULL;
2470 	struct ext4_fs_context *s_ctx = NULL;
2471 	struct fs_context *fc = NULL;
2472 	int ret = -ENOMEM;
2473 
2474 	if (!sbi->s_es->s_mount_opts[0])
2475 		return 0;
2476 
2477 	s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
2478 				sizeof(sbi->s_es->s_mount_opts),
2479 				GFP_KERNEL);
2480 	if (!s_mount_opts)
2481 		return ret;
2482 
2483 	fc = kzalloc(sizeof(struct fs_context), GFP_KERNEL);
2484 	if (!fc)
2485 		goto out_free;
2486 
2487 	s_ctx = kzalloc(sizeof(struct ext4_fs_context), GFP_KERNEL);
2488 	if (!s_ctx)
2489 		goto out_free;
2490 
2491 	fc->fs_private = s_ctx;
2492 	fc->s_fs_info = sbi;
2493 
2494 	ret = parse_options(fc, s_mount_opts);
2495 	if (ret < 0)
2496 		goto parse_failed;
2497 
2498 	ret = ext4_check_opt_consistency(fc, sb);
2499 	if (ret < 0) {
2500 parse_failed:
2501 		ext4_msg(sb, KERN_WARNING,
2502 			 "failed to parse options in superblock: %s",
2503 			 s_mount_opts);
2504 		ret = 0;
2505 		goto out_free;
2506 	}
2507 
2508 	if (s_ctx->spec & EXT4_SPEC_JOURNAL_DEV)
2509 		m_ctx->journal_devnum = s_ctx->journal_devnum;
2510 	if (s_ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)
2511 		m_ctx->journal_ioprio = s_ctx->journal_ioprio;
2512 
2513 	ext4_apply_options(fc, sb);
2514 	ret = 0;
2515 
2516 out_free:
2517 	if (fc) {
2518 		ext4_fc_free(fc);
2519 		kfree(fc);
2520 	}
2521 	kfree(s_mount_opts);
2522 	return ret;
2523 }
2524 
2525 static void ext4_apply_quota_options(struct fs_context *fc,
2526 				     struct super_block *sb)
2527 {
2528 #ifdef CONFIG_QUOTA
2529 	bool quota_feature = ext4_has_feature_quota(sb);
2530 	struct ext4_fs_context *ctx = fc->fs_private;
2531 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2532 	char *qname;
2533 	int i;
2534 
2535 	if (quota_feature)
2536 		return;
2537 
2538 	if (ctx->spec & EXT4_SPEC_JQUOTA) {
2539 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2540 			if (!(ctx->qname_spec & (1 << i)))
2541 				continue;
2542 
2543 			qname = ctx->s_qf_names[i]; /* May be NULL */
2544 			if (qname)
2545 				set_opt(sb, QUOTA);
2546 			ctx->s_qf_names[i] = NULL;
2547 			qname = rcu_replace_pointer(sbi->s_qf_names[i], qname,
2548 						lockdep_is_held(&sb->s_umount));
2549 			if (qname)
2550 				kfree_rcu_mightsleep(qname);
2551 		}
2552 	}
2553 
2554 	if (ctx->spec & EXT4_SPEC_JQFMT)
2555 		sbi->s_jquota_fmt = ctx->s_jquota_fmt;
2556 #endif
2557 }
2558 
2559 /*
2560  * Check quota settings consistency.
2561  */
2562 static int ext4_check_quota_consistency(struct fs_context *fc,
2563 					struct super_block *sb)
2564 {
2565 #ifdef CONFIG_QUOTA
2566 	struct ext4_fs_context *ctx = fc->fs_private;
2567 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2568 	bool quota_feature = ext4_has_feature_quota(sb);
2569 	bool quota_loaded = sb_any_quota_loaded(sb);
2570 	bool usr_qf_name, grp_qf_name, usrquota, grpquota;
2571 	int quota_flags, i;
2572 
2573 	/*
2574 	 * We do the test below only for project quotas. 'usrquota' and
2575 	 * 'grpquota' mount options are allowed even without quota feature
2576 	 * to support legacy quotas in quota files.
2577 	 */
2578 	if (ctx_test_mount_opt(ctx, EXT4_MOUNT_PRJQUOTA) &&
2579 	    !ext4_has_feature_project(sb)) {
2580 		ext4_msg(NULL, KERN_ERR, "Project quota feature not enabled. "
2581 			 "Cannot enable project quota enforcement.");
2582 		return -EINVAL;
2583 	}
2584 
2585 	quota_flags = EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2586 		      EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA;
2587 	if (quota_loaded &&
2588 	    ctx->mask_s_mount_opt & quota_flags &&
2589 	    !ctx_test_mount_opt(ctx, quota_flags))
2590 		goto err_quota_change;
2591 
2592 	if (ctx->spec & EXT4_SPEC_JQUOTA) {
2593 
2594 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2595 			if (!(ctx->qname_spec & (1 << i)))
2596 				continue;
2597 
2598 			if (quota_loaded &&
2599 			    !!sbi->s_qf_names[i] != !!ctx->s_qf_names[i])
2600 				goto err_jquota_change;
2601 
2602 			if (sbi->s_qf_names[i] && ctx->s_qf_names[i] &&
2603 			    strcmp(get_qf_name(sb, sbi, i),
2604 				   ctx->s_qf_names[i]) != 0)
2605 				goto err_jquota_specified;
2606 		}
2607 
2608 		if (quota_feature) {
2609 			ext4_msg(NULL, KERN_INFO,
2610 				 "Journaled quota options ignored when "
2611 				 "QUOTA feature is enabled");
2612 			return 0;
2613 		}
2614 	}
2615 
2616 	if (ctx->spec & EXT4_SPEC_JQFMT) {
2617 		if (sbi->s_jquota_fmt != ctx->s_jquota_fmt && quota_loaded)
2618 			goto err_jquota_change;
2619 		if (quota_feature) {
2620 			ext4_msg(NULL, KERN_INFO, "Quota format mount options "
2621 				 "ignored when QUOTA feature is enabled");
2622 			return 0;
2623 		}
2624 	}
2625 
2626 	/* Make sure we don't mix old and new quota format */
2627 	usr_qf_name = (get_qf_name(sb, sbi, USRQUOTA) ||
2628 		       ctx->s_qf_names[USRQUOTA]);
2629 	grp_qf_name = (get_qf_name(sb, sbi, GRPQUOTA) ||
2630 		       ctx->s_qf_names[GRPQUOTA]);
2631 
2632 	usrquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2633 		    test_opt(sb, USRQUOTA));
2634 
2635 	grpquota = (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) ||
2636 		    test_opt(sb, GRPQUOTA));
2637 
2638 	if (usr_qf_name) {
2639 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2640 		usrquota = false;
2641 	}
2642 	if (grp_qf_name) {
2643 		ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2644 		grpquota = false;
2645 	}
2646 
2647 	if (usr_qf_name || grp_qf_name) {
2648 		if (usrquota || grpquota) {
2649 			ext4_msg(NULL, KERN_ERR, "old and new quota "
2650 				 "format mixing");
2651 			return -EINVAL;
2652 		}
2653 
2654 		if (!(ctx->spec & EXT4_SPEC_JQFMT || sbi->s_jquota_fmt)) {
2655 			ext4_msg(NULL, KERN_ERR, "journaled quota format "
2656 				 "not specified");
2657 			return -EINVAL;
2658 		}
2659 	}
2660 
2661 	return 0;
2662 
2663 err_quota_change:
2664 	ext4_msg(NULL, KERN_ERR,
2665 		 "Cannot change quota options when quota turned on");
2666 	return -EINVAL;
2667 err_jquota_change:
2668 	ext4_msg(NULL, KERN_ERR, "Cannot change journaled quota "
2669 		 "options when quota turned on");
2670 	return -EINVAL;
2671 err_jquota_specified:
2672 	ext4_msg(NULL, KERN_ERR, "%s quota file already specified",
2673 		 QTYPE2NAME(i));
2674 	return -EINVAL;
2675 #else
2676 	return 0;
2677 #endif
2678 }
2679 
2680 static int ext4_check_test_dummy_encryption(const struct fs_context *fc,
2681 					    struct super_block *sb)
2682 {
2683 	const struct ext4_fs_context *ctx = fc->fs_private;
2684 	const struct ext4_sb_info *sbi = EXT4_SB(sb);
2685 
2686 	if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy))
2687 		return 0;
2688 
2689 	if (!ext4_has_feature_encrypt(sb)) {
2690 		ext4_msg(NULL, KERN_WARNING,
2691 			 "test_dummy_encryption requires encrypt feature");
2692 		return -EINVAL;
2693 	}
2694 	/*
2695 	 * This mount option is just for testing, and it's not worthwhile to
2696 	 * implement the extra complexity (e.g. RCU protection) that would be
2697 	 * needed to allow it to be set or changed during remount.  We do allow
2698 	 * it to be specified during remount, but only if there is no change.
2699 	 */
2700 	if (fc->purpose == FS_CONTEXT_FOR_RECONFIGURE) {
2701 		if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2702 						 &ctx->dummy_enc_policy))
2703 			return 0;
2704 		ext4_msg(NULL, KERN_WARNING,
2705 			 "Can't set or change test_dummy_encryption on remount");
2706 		return -EINVAL;
2707 	}
2708 	/* Also make sure s_mount_opts didn't contain a conflicting value. */
2709 	if (fscrypt_is_dummy_policy_set(&sbi->s_dummy_enc_policy)) {
2710 		if (fscrypt_dummy_policies_equal(&sbi->s_dummy_enc_policy,
2711 						 &ctx->dummy_enc_policy))
2712 			return 0;
2713 		ext4_msg(NULL, KERN_WARNING,
2714 			 "Conflicting test_dummy_encryption options");
2715 		return -EINVAL;
2716 	}
2717 	return 0;
2718 }
2719 
2720 static void ext4_apply_test_dummy_encryption(struct ext4_fs_context *ctx,
2721 					     struct super_block *sb)
2722 {
2723 	if (!fscrypt_is_dummy_policy_set(&ctx->dummy_enc_policy) ||
2724 	    /* if already set, it was already verified to be the same */
2725 	    fscrypt_is_dummy_policy_set(&EXT4_SB(sb)->s_dummy_enc_policy))
2726 		return;
2727 	EXT4_SB(sb)->s_dummy_enc_policy = ctx->dummy_enc_policy;
2728 	memset(&ctx->dummy_enc_policy, 0, sizeof(ctx->dummy_enc_policy));
2729 	ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2730 }
2731 
2732 static int ext4_check_opt_consistency(struct fs_context *fc,
2733 				      struct super_block *sb)
2734 {
2735 	struct ext4_fs_context *ctx = fc->fs_private;
2736 	struct ext4_sb_info *sbi = fc->s_fs_info;
2737 	int is_remount = fc->purpose == FS_CONTEXT_FOR_RECONFIGURE;
2738 	int err;
2739 
2740 	if ((ctx->opt_flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2741 		ext4_msg(NULL, KERN_ERR,
2742 			 "Mount option(s) incompatible with ext2");
2743 		return -EINVAL;
2744 	}
2745 	if ((ctx->opt_flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2746 		ext4_msg(NULL, KERN_ERR,
2747 			 "Mount option(s) incompatible with ext3");
2748 		return -EINVAL;
2749 	}
2750 
2751 	if (ctx->s_want_extra_isize >
2752 	    (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE)) {
2753 		ext4_msg(NULL, KERN_ERR,
2754 			 "Invalid want_extra_isize %d",
2755 			 ctx->s_want_extra_isize);
2756 		return -EINVAL;
2757 	}
2758 
2759 	err = ext4_check_test_dummy_encryption(fc, sb);
2760 	if (err)
2761 		return err;
2762 
2763 	if ((ctx->spec & EXT4_SPEC_DATAJ) && is_remount) {
2764 		if (!sbi->s_journal) {
2765 			ext4_msg(NULL, KERN_WARNING,
2766 				 "Remounting file system with no journal "
2767 				 "so ignoring journalled data option");
2768 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS);
2769 		} else if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_FLAGS) !=
2770 			   test_opt(sb, DATA_FLAGS)) {
2771 			ext4_msg(NULL, KERN_ERR, "Cannot change data mode "
2772 				 "on remount");
2773 			return -EINVAL;
2774 		}
2775 	}
2776 
2777 	if (is_remount) {
2778 		if (!sbi->s_journal &&
2779 		    ctx_test_mount_opt(ctx, EXT4_MOUNT_DATA_ERR_ABORT)) {
2780 			ext4_msg(NULL, KERN_WARNING,
2781 				 "Remounting fs w/o journal so ignoring data_err option");
2782 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_DATA_ERR_ABORT);
2783 		}
2784 
2785 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2786 		    (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2787 			ext4_msg(NULL, KERN_ERR, "can't mount with "
2788 				 "both data=journal and dax");
2789 			return -EINVAL;
2790 		}
2791 
2792 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_DAX_ALWAYS) &&
2793 		    (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2794 		     (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2795 fail_dax_change_remount:
2796 			ext4_msg(NULL, KERN_ERR, "can't change "
2797 				 "dax mount option while remounting");
2798 			return -EINVAL;
2799 		} else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_NEVER) &&
2800 			 (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2801 			  (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS))) {
2802 			goto fail_dax_change_remount;
2803 		} else if (ctx_test_mount_opt2(ctx, EXT4_MOUNT2_DAX_INODE) &&
2804 			   ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2805 			    (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2806 			    !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE))) {
2807 			goto fail_dax_change_remount;
2808 		}
2809 	}
2810 
2811 	return ext4_check_quota_consistency(fc, sb);
2812 }
2813 
2814 static void ext4_apply_options(struct fs_context *fc, struct super_block *sb)
2815 {
2816 	struct ext4_fs_context *ctx = fc->fs_private;
2817 	struct ext4_sb_info *sbi = fc->s_fs_info;
2818 
2819 	sbi->s_mount_opt &= ~ctx->mask_s_mount_opt;
2820 	sbi->s_mount_opt |= ctx->vals_s_mount_opt;
2821 	sbi->s_mount_opt2 &= ~ctx->mask_s_mount_opt2;
2822 	sbi->s_mount_opt2 |= ctx->vals_s_mount_opt2;
2823 	sb->s_flags &= ~ctx->mask_s_flags;
2824 	sb->s_flags |= ctx->vals_s_flags;
2825 
2826 #define APPLY(X) ({ if (ctx->spec & EXT4_SPEC_##X) sbi->X = ctx->X; })
2827 	APPLY(s_commit_interval);
2828 	APPLY(s_stripe);
2829 	APPLY(s_max_batch_time);
2830 	APPLY(s_min_batch_time);
2831 	APPLY(s_want_extra_isize);
2832 	APPLY(s_inode_readahead_blks);
2833 	APPLY(s_max_dir_size_kb);
2834 	APPLY(s_li_wait_mult);
2835 	APPLY(s_resgid);
2836 	APPLY(s_resuid);
2837 
2838 #ifdef CONFIG_EXT4_DEBUG
2839 	APPLY(s_fc_debug_max_replay);
2840 #endif
2841 
2842 	ext4_apply_quota_options(fc, sb);
2843 	ext4_apply_test_dummy_encryption(ctx, sb);
2844 }
2845 
2846 
2847 static int ext4_validate_options(struct fs_context *fc)
2848 {
2849 #ifdef CONFIG_QUOTA
2850 	struct ext4_fs_context *ctx = fc->fs_private;
2851 	char *usr_qf_name, *grp_qf_name;
2852 
2853 	usr_qf_name = ctx->s_qf_names[USRQUOTA];
2854 	grp_qf_name = ctx->s_qf_names[GRPQUOTA];
2855 
2856 	if (usr_qf_name || grp_qf_name) {
2857 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) && usr_qf_name)
2858 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_USRQUOTA);
2859 
2860 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA) && grp_qf_name)
2861 			ctx_clear_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA);
2862 
2863 		if (ctx_test_mount_opt(ctx, EXT4_MOUNT_USRQUOTA) ||
2864 		    ctx_test_mount_opt(ctx, EXT4_MOUNT_GRPQUOTA)) {
2865 			ext4_msg(NULL, KERN_ERR, "old and new quota "
2866 				 "format mixing");
2867 			return -EINVAL;
2868 		}
2869 	}
2870 #endif
2871 	return 1;
2872 }
2873 
2874 static inline void ext4_show_quota_options(struct seq_file *seq,
2875 					   struct super_block *sb)
2876 {
2877 #if defined(CONFIG_QUOTA)
2878 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2879 	char *usr_qf_name, *grp_qf_name;
2880 
2881 	if (sbi->s_jquota_fmt) {
2882 		char *fmtname = "";
2883 
2884 		switch (sbi->s_jquota_fmt) {
2885 		case QFMT_VFS_OLD:
2886 			fmtname = "vfsold";
2887 			break;
2888 		case QFMT_VFS_V0:
2889 			fmtname = "vfsv0";
2890 			break;
2891 		case QFMT_VFS_V1:
2892 			fmtname = "vfsv1";
2893 			break;
2894 		}
2895 		seq_printf(seq, ",jqfmt=%s", fmtname);
2896 	}
2897 
2898 	rcu_read_lock();
2899 	usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2900 	grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2901 	if (usr_qf_name)
2902 		seq_show_option(seq, "usrjquota", usr_qf_name);
2903 	if (grp_qf_name)
2904 		seq_show_option(seq, "grpjquota", grp_qf_name);
2905 	rcu_read_unlock();
2906 #endif
2907 }
2908 
2909 static const char *token2str(int token)
2910 {
2911 	const struct fs_parameter_spec *spec;
2912 
2913 	for (spec = ext4_param_specs; spec->name != NULL; spec++)
2914 		if (spec->opt == token && !spec->type)
2915 			break;
2916 	return spec->name;
2917 }
2918 
2919 /*
2920  * Show an option if
2921  *  - it's set to a non-default value OR
2922  *  - if the per-sb default is different from the global default
2923  */
2924 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2925 			      int nodefs)
2926 {
2927 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2928 	struct ext4_super_block *es = sbi->s_es;
2929 	int def_errors;
2930 	const struct mount_opts *m;
2931 	char sep = nodefs ? '\n' : ',';
2932 
2933 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2934 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2935 
2936 	if (sbi->s_sb_block != 1)
2937 		SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2938 
2939 	for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2940 		int want_set = m->flags & MOPT_SET;
2941 		int opt_2 = m->flags & MOPT_2;
2942 		unsigned int mount_opt, def_mount_opt;
2943 
2944 		if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2945 		    m->flags & MOPT_SKIP)
2946 			continue;
2947 
2948 		if (opt_2) {
2949 			mount_opt = sbi->s_mount_opt2;
2950 			def_mount_opt = sbi->s_def_mount_opt2;
2951 		} else {
2952 			mount_opt = sbi->s_mount_opt;
2953 			def_mount_opt = sbi->s_def_mount_opt;
2954 		}
2955 		/* skip if same as the default */
2956 		if (!nodefs && !(m->mount_opt & (mount_opt ^ def_mount_opt)))
2957 			continue;
2958 		/* select Opt_noFoo vs Opt_Foo */
2959 		if ((want_set &&
2960 		     (mount_opt & m->mount_opt) != m->mount_opt) ||
2961 		    (!want_set && (mount_opt & m->mount_opt)))
2962 			continue;
2963 		SEQ_OPTS_PRINT("%s", token2str(m->token));
2964 	}
2965 
2966 	if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2967 	    le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2968 		SEQ_OPTS_PRINT("resuid=%u",
2969 				from_kuid_munged(&init_user_ns, sbi->s_resuid));
2970 	if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2971 	    le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2972 		SEQ_OPTS_PRINT("resgid=%u",
2973 				from_kgid_munged(&init_user_ns, sbi->s_resgid));
2974 	def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2975 	if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2976 		SEQ_OPTS_PUTS("errors=remount-ro");
2977 	if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2978 		SEQ_OPTS_PUTS("errors=continue");
2979 	if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2980 		SEQ_OPTS_PUTS("errors=panic");
2981 	if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2982 		SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2983 	if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2984 		SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2985 	if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2986 		SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2987 	if (nodefs && sb->s_flags & SB_I_VERSION)
2988 		SEQ_OPTS_PUTS("i_version");
2989 	if (nodefs || sbi->s_stripe)
2990 		SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2991 	if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2992 			(sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
2993 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2994 			SEQ_OPTS_PUTS("data=journal");
2995 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2996 			SEQ_OPTS_PUTS("data=ordered");
2997 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2998 			SEQ_OPTS_PUTS("data=writeback");
2999 	}
3000 	if (nodefs ||
3001 	    sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
3002 		SEQ_OPTS_PRINT("inode_readahead_blks=%u",
3003 			       sbi->s_inode_readahead_blks);
3004 
3005 	if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
3006 		       (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
3007 		SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
3008 	if (nodefs || sbi->s_max_dir_size_kb)
3009 		SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
3010 	if (test_opt(sb, DATA_ERR_ABORT))
3011 		SEQ_OPTS_PUTS("data_err=abort");
3012 
3013 	fscrypt_show_test_dummy_encryption(seq, sep, sb);
3014 
3015 	if (sb->s_flags & SB_INLINECRYPT)
3016 		SEQ_OPTS_PUTS("inlinecrypt");
3017 
3018 	if (test_opt(sb, DAX_ALWAYS)) {
3019 		if (IS_EXT2_SB(sb))
3020 			SEQ_OPTS_PUTS("dax");
3021 		else
3022 			SEQ_OPTS_PUTS("dax=always");
3023 	} else if (test_opt2(sb, DAX_NEVER)) {
3024 		SEQ_OPTS_PUTS("dax=never");
3025 	} else if (test_opt2(sb, DAX_INODE)) {
3026 		SEQ_OPTS_PUTS("dax=inode");
3027 	}
3028 
3029 	if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3030 			!test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3031 		SEQ_OPTS_PUTS("mb_optimize_scan=0");
3032 	} else if (sbi->s_groups_count < MB_DEFAULT_LINEAR_SCAN_THRESHOLD &&
3033 			test_opt2(sb, MB_OPTIMIZE_SCAN)) {
3034 		SEQ_OPTS_PUTS("mb_optimize_scan=1");
3035 	}
3036 
3037 	if (nodefs && !test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS))
3038 		SEQ_OPTS_PUTS("prefetch_block_bitmaps");
3039 
3040 	if (ext4_emergency_ro(sb))
3041 		SEQ_OPTS_PUTS("emergency_ro");
3042 
3043 	if (ext4_forced_shutdown(sb))
3044 		SEQ_OPTS_PUTS("shutdown");
3045 
3046 	ext4_show_quota_options(seq, sb);
3047 	return 0;
3048 }
3049 
3050 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
3051 {
3052 	return _ext4_show_options(seq, root->d_sb, 0);
3053 }
3054 
3055 int ext4_seq_options_show(struct seq_file *seq, void *offset)
3056 {
3057 	struct super_block *sb = seq->private;
3058 	int rc;
3059 
3060 	seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
3061 	rc = _ext4_show_options(seq, sb, 1);
3062 	seq_putc(seq, '\n');
3063 	return rc;
3064 }
3065 
3066 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
3067 			    int read_only)
3068 {
3069 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3070 	int err = 0;
3071 
3072 	if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
3073 		ext4_msg(sb, KERN_ERR, "revision level too high, "
3074 			 "forcing read-only mode");
3075 		err = -EROFS;
3076 		goto done;
3077 	}
3078 	if (read_only)
3079 		goto done;
3080 	if (!(sbi->s_mount_state & EXT4_VALID_FS))
3081 		ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
3082 			 "running e2fsck is recommended");
3083 	else if (sbi->s_mount_state & EXT4_ERROR_FS)
3084 		ext4_msg(sb, KERN_WARNING,
3085 			 "warning: mounting fs with errors, "
3086 			 "running e2fsck is recommended");
3087 	else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
3088 		 le16_to_cpu(es->s_mnt_count) >=
3089 		 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
3090 		ext4_msg(sb, KERN_WARNING,
3091 			 "warning: maximal mount count reached, "
3092 			 "running e2fsck is recommended");
3093 	else if (le32_to_cpu(es->s_checkinterval) &&
3094 		 (ext4_get_tstamp(es, s_lastcheck) +
3095 		  le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
3096 		ext4_msg(sb, KERN_WARNING,
3097 			 "warning: checktime reached, "
3098 			 "running e2fsck is recommended");
3099 	if (!sbi->s_journal)
3100 		es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
3101 	if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
3102 		es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
3103 	le16_add_cpu(&es->s_mnt_count, 1);
3104 	ext4_update_tstamp(es, s_mtime);
3105 	if (sbi->s_journal) {
3106 		ext4_set_feature_journal_needs_recovery(sb);
3107 		if (ext4_has_feature_orphan_file(sb))
3108 			ext4_set_feature_orphan_present(sb);
3109 	}
3110 
3111 	err = ext4_commit_super(sb);
3112 done:
3113 	if (test_opt(sb, DEBUG))
3114 		printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
3115 				"bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
3116 			sb->s_blocksize,
3117 			sbi->s_groups_count,
3118 			EXT4_BLOCKS_PER_GROUP(sb),
3119 			EXT4_INODES_PER_GROUP(sb),
3120 			sbi->s_mount_opt, sbi->s_mount_opt2);
3121 	return err;
3122 }
3123 
3124 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
3125 {
3126 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3127 	struct flex_groups **old_groups, **new_groups;
3128 	int size, i, j;
3129 
3130 	if (!sbi->s_log_groups_per_flex)
3131 		return 0;
3132 
3133 	size = ext4_flex_group(sbi, ngroup - 1) + 1;
3134 	if (size <= sbi->s_flex_groups_allocated)
3135 		return 0;
3136 
3137 	new_groups = kvzalloc(roundup_pow_of_two(size *
3138 			      sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
3139 	if (!new_groups) {
3140 		ext4_msg(sb, KERN_ERR,
3141 			 "not enough memory for %d flex group pointers", size);
3142 		return -ENOMEM;
3143 	}
3144 	for (i = sbi->s_flex_groups_allocated; i < size; i++) {
3145 		new_groups[i] = kvzalloc(roundup_pow_of_two(
3146 					 sizeof(struct flex_groups)),
3147 					 GFP_KERNEL);
3148 		if (!new_groups[i]) {
3149 			for (j = sbi->s_flex_groups_allocated; j < i; j++)
3150 				kvfree(new_groups[j]);
3151 			kvfree(new_groups);
3152 			ext4_msg(sb, KERN_ERR,
3153 				 "not enough memory for %d flex groups", size);
3154 			return -ENOMEM;
3155 		}
3156 	}
3157 	rcu_read_lock();
3158 	old_groups = rcu_dereference(sbi->s_flex_groups);
3159 	if (old_groups)
3160 		memcpy(new_groups, old_groups,
3161 		       (sbi->s_flex_groups_allocated *
3162 			sizeof(struct flex_groups *)));
3163 	rcu_read_unlock();
3164 	rcu_assign_pointer(sbi->s_flex_groups, new_groups);
3165 	sbi->s_flex_groups_allocated = size;
3166 	if (old_groups)
3167 		ext4_kvfree_array_rcu(old_groups);
3168 	return 0;
3169 }
3170 
3171 static int ext4_fill_flex_info(struct super_block *sb)
3172 {
3173 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3174 	struct ext4_group_desc *gdp = NULL;
3175 	struct flex_groups *fg;
3176 	ext4_group_t flex_group;
3177 	int i, err;
3178 
3179 	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
3180 	if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
3181 		sbi->s_log_groups_per_flex = 0;
3182 		return 1;
3183 	}
3184 
3185 	err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
3186 	if (err)
3187 		goto failed;
3188 
3189 	for (i = 0; i < sbi->s_groups_count; i++) {
3190 		gdp = ext4_get_group_desc(sb, i, NULL);
3191 
3192 		flex_group = ext4_flex_group(sbi, i);
3193 		fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
3194 		atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
3195 		atomic64_add(ext4_free_group_clusters(sb, gdp),
3196 			     &fg->free_clusters);
3197 		atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
3198 	}
3199 
3200 	return 1;
3201 failed:
3202 	return 0;
3203 }
3204 
3205 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
3206 				   struct ext4_group_desc *gdp)
3207 {
3208 	int offset = offsetof(struct ext4_group_desc, bg_checksum);
3209 	__u16 crc = 0;
3210 	__le32 le_group = cpu_to_le32(block_group);
3211 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3212 
3213 	if (ext4_has_feature_metadata_csum(sbi->s_sb)) {
3214 		/* Use new metadata_csum algorithm */
3215 		__u32 csum32;
3216 		__u16 dummy_csum = 0;
3217 
3218 		csum32 = ext4_chksum(sbi->s_csum_seed, (__u8 *)&le_group,
3219 				     sizeof(le_group));
3220 		csum32 = ext4_chksum(csum32, (__u8 *)gdp, offset);
3221 		csum32 = ext4_chksum(csum32, (__u8 *)&dummy_csum,
3222 				     sizeof(dummy_csum));
3223 		offset += sizeof(dummy_csum);
3224 		if (offset < sbi->s_desc_size)
3225 			csum32 = ext4_chksum(csum32, (__u8 *)gdp + offset,
3226 					     sbi->s_desc_size - offset);
3227 
3228 		crc = csum32 & 0xFFFF;
3229 		goto out;
3230 	}
3231 
3232 	/* old crc16 code */
3233 	if (!ext4_has_feature_gdt_csum(sb))
3234 		return 0;
3235 
3236 	crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
3237 	crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
3238 	crc = crc16(crc, (__u8 *)gdp, offset);
3239 	offset += sizeof(gdp->bg_checksum); /* skip checksum */
3240 	/* for checksum of struct ext4_group_desc do the rest...*/
3241 	if (ext4_has_feature_64bit(sb) && offset < sbi->s_desc_size)
3242 		crc = crc16(crc, (__u8 *)gdp + offset,
3243 			    sbi->s_desc_size - offset);
3244 
3245 out:
3246 	return cpu_to_le16(crc);
3247 }
3248 
3249 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
3250 				struct ext4_group_desc *gdp)
3251 {
3252 	if (ext4_has_group_desc_csum(sb) &&
3253 	    (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
3254 		return 0;
3255 
3256 	return 1;
3257 }
3258 
3259 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
3260 			      struct ext4_group_desc *gdp)
3261 {
3262 	if (!ext4_has_group_desc_csum(sb))
3263 		return;
3264 	gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
3265 }
3266 
3267 /* Called at mount-time, super-block is locked */
3268 static int ext4_check_descriptors(struct super_block *sb,
3269 				  ext4_fsblk_t sb_block,
3270 				  ext4_group_t *first_not_zeroed)
3271 {
3272 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3273 	ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
3274 	ext4_fsblk_t last_block;
3275 	ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
3276 	ext4_fsblk_t block_bitmap;
3277 	ext4_fsblk_t inode_bitmap;
3278 	ext4_fsblk_t inode_table;
3279 	int flexbg_flag = 0;
3280 	ext4_group_t i, grp = sbi->s_groups_count;
3281 
3282 	if (ext4_has_feature_flex_bg(sb))
3283 		flexbg_flag = 1;
3284 
3285 	ext4_debug("Checking group descriptors");
3286 
3287 	for (i = 0; i < sbi->s_groups_count; i++) {
3288 		struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
3289 
3290 		if (i == sbi->s_groups_count - 1 || flexbg_flag)
3291 			last_block = ext4_blocks_count(sbi->s_es) - 1;
3292 		else
3293 			last_block = first_block +
3294 				(EXT4_BLOCKS_PER_GROUP(sb) - 1);
3295 
3296 		if ((grp == sbi->s_groups_count) &&
3297 		   !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3298 			grp = i;
3299 
3300 		block_bitmap = ext4_block_bitmap(sb, gdp);
3301 		if (block_bitmap == sb_block) {
3302 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3303 				 "Block bitmap for group %u overlaps "
3304 				 "superblock", i);
3305 			if (!sb_rdonly(sb))
3306 				return 0;
3307 		}
3308 		if (block_bitmap >= sb_block + 1 &&
3309 		    block_bitmap <= last_bg_block) {
3310 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3311 				 "Block bitmap for group %u overlaps "
3312 				 "block group descriptors", i);
3313 			if (!sb_rdonly(sb))
3314 				return 0;
3315 		}
3316 		if (block_bitmap < first_block || block_bitmap > last_block) {
3317 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3318 			       "Block bitmap for group %u not in group "
3319 			       "(block %llu)!", i, block_bitmap);
3320 			return 0;
3321 		}
3322 		inode_bitmap = ext4_inode_bitmap(sb, gdp);
3323 		if (inode_bitmap == sb_block) {
3324 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3325 				 "Inode bitmap for group %u overlaps "
3326 				 "superblock", i);
3327 			if (!sb_rdonly(sb))
3328 				return 0;
3329 		}
3330 		if (inode_bitmap >= sb_block + 1 &&
3331 		    inode_bitmap <= last_bg_block) {
3332 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3333 				 "Inode bitmap for group %u overlaps "
3334 				 "block group descriptors", i);
3335 			if (!sb_rdonly(sb))
3336 				return 0;
3337 		}
3338 		if (inode_bitmap < first_block || inode_bitmap > last_block) {
3339 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3340 			       "Inode bitmap for group %u not in group "
3341 			       "(block %llu)!", i, inode_bitmap);
3342 			return 0;
3343 		}
3344 		inode_table = ext4_inode_table(sb, gdp);
3345 		if (inode_table == sb_block) {
3346 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3347 				 "Inode table for group %u overlaps "
3348 				 "superblock", i);
3349 			if (!sb_rdonly(sb))
3350 				return 0;
3351 		}
3352 		if (inode_table >= sb_block + 1 &&
3353 		    inode_table <= last_bg_block) {
3354 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3355 				 "Inode table for group %u overlaps "
3356 				 "block group descriptors", i);
3357 			if (!sb_rdonly(sb))
3358 				return 0;
3359 		}
3360 		if (inode_table < first_block ||
3361 		    inode_table + sbi->s_itb_per_group - 1 > last_block) {
3362 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3363 			       "Inode table for group %u not in group "
3364 			       "(block %llu)!", i, inode_table);
3365 			return 0;
3366 		}
3367 		ext4_lock_group(sb, i);
3368 		if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
3369 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
3370 				 "Checksum for group %u failed (%u!=%u)",
3371 				 i, le16_to_cpu(ext4_group_desc_csum(sb, i,
3372 				     gdp)), le16_to_cpu(gdp->bg_checksum));
3373 			if (!sb_rdonly(sb)) {
3374 				ext4_unlock_group(sb, i);
3375 				return 0;
3376 			}
3377 		}
3378 		ext4_unlock_group(sb, i);
3379 		if (!flexbg_flag)
3380 			first_block += EXT4_BLOCKS_PER_GROUP(sb);
3381 	}
3382 	if (NULL != first_not_zeroed)
3383 		*first_not_zeroed = grp;
3384 	return 1;
3385 }
3386 
3387 /*
3388  * Maximal extent format file size.
3389  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3390  * extent format containers, within a sector_t, and within i_blocks
3391  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3392  * so that won't be a limiting factor.
3393  *
3394  * However there is other limiting factor. We do store extents in the form
3395  * of starting block and length, hence the resulting length of the extent
3396  * covering maximum file size must fit into on-disk format containers as
3397  * well. Given that length is always by 1 unit bigger than max unit (because
3398  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3399  *
3400  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3401  */
3402 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3403 {
3404 	loff_t res;
3405 	loff_t upper_limit = MAX_LFS_FILESIZE;
3406 
3407 	BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3408 
3409 	if (!has_huge_files) {
3410 		upper_limit = (1LL << 32) - 1;
3411 
3412 		/* total blocks in file system block size */
3413 		upper_limit >>= (blkbits - 9);
3414 		upper_limit <<= blkbits;
3415 	}
3416 
3417 	/*
3418 	 * 32-bit extent-start container, ee_block. We lower the maxbytes
3419 	 * by one fs block, so ee_len can cover the extent of maximum file
3420 	 * size
3421 	 */
3422 	res = (1LL << 32) - 1;
3423 	res <<= blkbits;
3424 
3425 	/* Sanity check against vm- & vfs- imposed limits */
3426 	if (res > upper_limit)
3427 		res = upper_limit;
3428 
3429 	return res;
3430 }
3431 
3432 /*
3433  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3434  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3435  * We need to be 1 filesystem block less than the 2^48 sector limit.
3436  */
3437 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3438 {
3439 	loff_t upper_limit, res = EXT4_NDIR_BLOCKS;
3440 	int meta_blocks;
3441 	unsigned int ppb = 1 << (bits - 2);
3442 
3443 	/*
3444 	 * This is calculated to be the largest file size for a dense, block
3445 	 * mapped file such that the file's total number of 512-byte sectors,
3446 	 * including data and all indirect blocks, does not exceed (2^48 - 1).
3447 	 *
3448 	 * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3449 	 * number of 512-byte sectors of the file.
3450 	 */
3451 	if (!has_huge_files) {
3452 		/*
3453 		 * !has_huge_files or implies that the inode i_block field
3454 		 * represents total file blocks in 2^32 512-byte sectors ==
3455 		 * size of vfs inode i_blocks * 8
3456 		 */
3457 		upper_limit = (1LL << 32) - 1;
3458 
3459 		/* total blocks in file system block size */
3460 		upper_limit >>= (bits - 9);
3461 
3462 	} else {
3463 		/*
3464 		 * We use 48 bit ext4_inode i_blocks
3465 		 * With EXT4_HUGE_FILE_FL set the i_blocks
3466 		 * represent total number of blocks in
3467 		 * file system block size
3468 		 */
3469 		upper_limit = (1LL << 48) - 1;
3470 
3471 	}
3472 
3473 	/* Compute how many blocks we can address by block tree */
3474 	res += ppb;
3475 	res += ppb * ppb;
3476 	res += ((loff_t)ppb) * ppb * ppb;
3477 	/* Compute how many metadata blocks are needed */
3478 	meta_blocks = 1;
3479 	meta_blocks += 1 + ppb;
3480 	meta_blocks += 1 + ppb + ppb * ppb;
3481 	/* Does block tree limit file size? */
3482 	if (res + meta_blocks <= upper_limit)
3483 		goto check_lfs;
3484 
3485 	res = upper_limit;
3486 	/* How many metadata blocks are needed for addressing upper_limit? */
3487 	upper_limit -= EXT4_NDIR_BLOCKS;
3488 	/* indirect blocks */
3489 	meta_blocks = 1;
3490 	upper_limit -= ppb;
3491 	/* double indirect blocks */
3492 	if (upper_limit < ppb * ppb) {
3493 		meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb);
3494 		res -= meta_blocks;
3495 		goto check_lfs;
3496 	}
3497 	meta_blocks += 1 + ppb;
3498 	upper_limit -= ppb * ppb;
3499 	/* tripple indirect blocks for the rest */
3500 	meta_blocks += 1 + DIV_ROUND_UP_ULL(upper_limit, ppb) +
3501 		DIV_ROUND_UP_ULL(upper_limit, ppb*ppb);
3502 	res -= meta_blocks;
3503 check_lfs:
3504 	res <<= bits;
3505 	if (res > MAX_LFS_FILESIZE)
3506 		res = MAX_LFS_FILESIZE;
3507 
3508 	return res;
3509 }
3510 
3511 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3512 				   ext4_fsblk_t logical_sb_block, int nr)
3513 {
3514 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3515 	ext4_group_t bg, first_meta_bg;
3516 	int has_super = 0;
3517 
3518 	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3519 
3520 	if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3521 		return logical_sb_block + nr + 1;
3522 	bg = sbi->s_desc_per_block * nr;
3523 	if (ext4_bg_has_super(sb, bg))
3524 		has_super = 1;
3525 
3526 	/*
3527 	 * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3528 	 * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3529 	 * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3530 	 * compensate.
3531 	 */
3532 	if (sb->s_blocksize == 1024 && nr == 0 &&
3533 	    le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3534 		has_super++;
3535 
3536 	return (has_super + ext4_group_first_block_no(sb, bg));
3537 }
3538 
3539 /**
3540  * ext4_get_stripe_size: Get the stripe size.
3541  * @sbi: In memory super block info
3542  *
3543  * If we have specified it via mount option, then
3544  * use the mount option value. If the value specified at mount time is
3545  * greater than the blocks per group use the super block value.
3546  * If the super block value is greater than blocks per group return 0.
3547  * Allocator needs it be less than blocks per group.
3548  *
3549  */
3550 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3551 {
3552 	unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3553 	unsigned long stripe_width =
3554 			le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3555 	int ret;
3556 
3557 	if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3558 		ret = sbi->s_stripe;
3559 	else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3560 		ret = stripe_width;
3561 	else if (stride && stride <= sbi->s_blocks_per_group)
3562 		ret = stride;
3563 	else
3564 		ret = 0;
3565 
3566 	/*
3567 	 * If the stripe width is 1, this makes no sense and
3568 	 * we set it to 0 to turn off stripe handling code.
3569 	 */
3570 	if (ret <= 1)
3571 		ret = 0;
3572 
3573 	return ret;
3574 }
3575 
3576 /*
3577  * Check whether this filesystem can be mounted based on
3578  * the features present and the RDONLY/RDWR mount requested.
3579  * Returns 1 if this filesystem can be mounted as requested,
3580  * 0 if it cannot be.
3581  */
3582 int ext4_feature_set_ok(struct super_block *sb, int readonly)
3583 {
3584 	if (ext4_has_unknown_ext4_incompat_features(sb)) {
3585 		ext4_msg(sb, KERN_ERR,
3586 			"Couldn't mount because of "
3587 			"unsupported optional features (%x)",
3588 			(le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3589 			~EXT4_FEATURE_INCOMPAT_SUPP));
3590 		return 0;
3591 	}
3592 
3593 	if (!IS_ENABLED(CONFIG_UNICODE) && ext4_has_feature_casefold(sb)) {
3594 		ext4_msg(sb, KERN_ERR,
3595 			 "Filesystem with casefold feature cannot be "
3596 			 "mounted without CONFIG_UNICODE");
3597 		return 0;
3598 	}
3599 
3600 	if (readonly)
3601 		return 1;
3602 
3603 	if (ext4_has_feature_readonly(sb)) {
3604 		ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3605 		sb->s_flags |= SB_RDONLY;
3606 		return 1;
3607 	}
3608 
3609 	/* Check that feature set is OK for a read-write mount */
3610 	if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3611 		ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3612 			 "unsupported optional features (%x)",
3613 			 (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3614 				~EXT4_FEATURE_RO_COMPAT_SUPP));
3615 		return 0;
3616 	}
3617 	if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3618 		ext4_msg(sb, KERN_ERR,
3619 			 "Can't support bigalloc feature without "
3620 			 "extents feature\n");
3621 		return 0;
3622 	}
3623 
3624 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3625 	if (!readonly && (ext4_has_feature_quota(sb) ||
3626 			  ext4_has_feature_project(sb))) {
3627 		ext4_msg(sb, KERN_ERR,
3628 			 "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3629 		return 0;
3630 	}
3631 #endif  /* CONFIG_QUOTA */
3632 	return 1;
3633 }
3634 
3635 /*
3636  * This function is called once a day if we have errors logged
3637  * on the file system
3638  */
3639 static void print_daily_error_info(struct timer_list *t)
3640 {
3641 	struct ext4_sb_info *sbi = timer_container_of(sbi, t, s_err_report);
3642 	struct super_block *sb = sbi->s_sb;
3643 	struct ext4_super_block *es = sbi->s_es;
3644 
3645 	if (es->s_error_count)
3646 		/* fsck newer than v1.41.13 is needed to clean this condition. */
3647 		ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3648 			 le32_to_cpu(es->s_error_count));
3649 	if (es->s_first_error_time) {
3650 		printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3651 		       sb->s_id,
3652 		       ext4_get_tstamp(es, s_first_error_time),
3653 		       (int) sizeof(es->s_first_error_func),
3654 		       es->s_first_error_func,
3655 		       le32_to_cpu(es->s_first_error_line));
3656 		if (es->s_first_error_ino)
3657 			printk(KERN_CONT ": inode %u",
3658 			       le32_to_cpu(es->s_first_error_ino));
3659 		if (es->s_first_error_block)
3660 			printk(KERN_CONT ": block %llu", (unsigned long long)
3661 			       le64_to_cpu(es->s_first_error_block));
3662 		printk(KERN_CONT "\n");
3663 	}
3664 	if (es->s_last_error_time) {
3665 		printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3666 		       sb->s_id,
3667 		       ext4_get_tstamp(es, s_last_error_time),
3668 		       (int) sizeof(es->s_last_error_func),
3669 		       es->s_last_error_func,
3670 		       le32_to_cpu(es->s_last_error_line));
3671 		if (es->s_last_error_ino)
3672 			printk(KERN_CONT ": inode %u",
3673 			       le32_to_cpu(es->s_last_error_ino));
3674 		if (es->s_last_error_block)
3675 			printk(KERN_CONT ": block %llu", (unsigned long long)
3676 			       le64_to_cpu(es->s_last_error_block));
3677 		printk(KERN_CONT "\n");
3678 	}
3679 	mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3680 }
3681 
3682 /* Find next suitable group and run ext4_init_inode_table */
3683 static int ext4_run_li_request(struct ext4_li_request *elr)
3684 {
3685 	struct ext4_group_desc *gdp = NULL;
3686 	struct super_block *sb = elr->lr_super;
3687 	ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3688 	ext4_group_t group = elr->lr_next_group;
3689 	unsigned int prefetch_ios = 0;
3690 	int ret = 0;
3691 	int nr = EXT4_SB(sb)->s_mb_prefetch;
3692 	u64 start_time;
3693 
3694 	if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3695 		elr->lr_next_group = ext4_mb_prefetch(sb, group, nr, &prefetch_ios);
3696 		ext4_mb_prefetch_fini(sb, elr->lr_next_group, nr);
3697 		trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group, nr);
3698 		if (group >= elr->lr_next_group) {
3699 			ret = 1;
3700 			if (elr->lr_first_not_zeroed != ngroups &&
3701 			    !ext4_emergency_state(sb) && !sb_rdonly(sb) &&
3702 			    test_opt(sb, INIT_INODE_TABLE)) {
3703 				elr->lr_next_group = elr->lr_first_not_zeroed;
3704 				elr->lr_mode = EXT4_LI_MODE_ITABLE;
3705 				ret = 0;
3706 			}
3707 		}
3708 		return ret;
3709 	}
3710 
3711 	for (; group < ngroups; group++) {
3712 		gdp = ext4_get_group_desc(sb, group, NULL);
3713 		if (!gdp) {
3714 			ret = 1;
3715 			break;
3716 		}
3717 
3718 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3719 			break;
3720 	}
3721 
3722 	if (group >= ngroups)
3723 		ret = 1;
3724 
3725 	if (!ret) {
3726 		start_time = ktime_get_ns();
3727 		ret = ext4_init_inode_table(sb, group,
3728 					    elr->lr_timeout ? 0 : 1);
3729 		trace_ext4_lazy_itable_init(sb, group);
3730 		if (elr->lr_timeout == 0) {
3731 			elr->lr_timeout = nsecs_to_jiffies((ktime_get_ns() - start_time) *
3732 				EXT4_SB(elr->lr_super)->s_li_wait_mult);
3733 		}
3734 		elr->lr_next_sched = jiffies + elr->lr_timeout;
3735 		elr->lr_next_group = group + 1;
3736 	}
3737 	return ret;
3738 }
3739 
3740 /*
3741  * Remove lr_request from the list_request and free the
3742  * request structure. Should be called with li_list_mtx held
3743  */
3744 static void ext4_remove_li_request(struct ext4_li_request *elr)
3745 {
3746 	if (!elr)
3747 		return;
3748 
3749 	list_del(&elr->lr_request);
3750 	EXT4_SB(elr->lr_super)->s_li_request = NULL;
3751 	kfree(elr);
3752 }
3753 
3754 static void ext4_unregister_li_request(struct super_block *sb)
3755 {
3756 	mutex_lock(&ext4_li_mtx);
3757 	if (!ext4_li_info) {
3758 		mutex_unlock(&ext4_li_mtx);
3759 		return;
3760 	}
3761 
3762 	mutex_lock(&ext4_li_info->li_list_mtx);
3763 	ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3764 	mutex_unlock(&ext4_li_info->li_list_mtx);
3765 	mutex_unlock(&ext4_li_mtx);
3766 }
3767 
3768 static struct task_struct *ext4_lazyinit_task;
3769 
3770 /*
3771  * This is the function where ext4lazyinit thread lives. It walks
3772  * through the request list searching for next scheduled filesystem.
3773  * When such a fs is found, run the lazy initialization request
3774  * (ext4_rn_li_request) and keep track of the time spend in this
3775  * function. Based on that time we compute next schedule time of
3776  * the request. When walking through the list is complete, compute
3777  * next waking time and put itself into sleep.
3778  */
3779 static int ext4_lazyinit_thread(void *arg)
3780 {
3781 	struct ext4_lazy_init *eli = arg;
3782 	struct list_head *pos, *n;
3783 	struct ext4_li_request *elr;
3784 	unsigned long next_wakeup, cur;
3785 
3786 	BUG_ON(NULL == eli);
3787 	set_freezable();
3788 
3789 cont_thread:
3790 	while (true) {
3791 		bool next_wakeup_initialized = false;
3792 
3793 		next_wakeup = 0;
3794 		mutex_lock(&eli->li_list_mtx);
3795 		if (list_empty(&eli->li_request_list)) {
3796 			mutex_unlock(&eli->li_list_mtx);
3797 			goto exit_thread;
3798 		}
3799 		list_for_each_safe(pos, n, &eli->li_request_list) {
3800 			int err = 0;
3801 			int progress = 0;
3802 			elr = list_entry(pos, struct ext4_li_request,
3803 					 lr_request);
3804 
3805 			if (time_before(jiffies, elr->lr_next_sched)) {
3806 				if (!next_wakeup_initialized ||
3807 				    time_before(elr->lr_next_sched, next_wakeup)) {
3808 					next_wakeup = elr->lr_next_sched;
3809 					next_wakeup_initialized = true;
3810 				}
3811 				continue;
3812 			}
3813 			if (down_read_trylock(&elr->lr_super->s_umount)) {
3814 				if (sb_start_write_trylock(elr->lr_super)) {
3815 					progress = 1;
3816 					/*
3817 					 * We hold sb->s_umount, sb can not
3818 					 * be removed from the list, it is
3819 					 * now safe to drop li_list_mtx
3820 					 */
3821 					mutex_unlock(&eli->li_list_mtx);
3822 					err = ext4_run_li_request(elr);
3823 					sb_end_write(elr->lr_super);
3824 					mutex_lock(&eli->li_list_mtx);
3825 					n = pos->next;
3826 				}
3827 				up_read((&elr->lr_super->s_umount));
3828 			}
3829 			/* error, remove the lazy_init job */
3830 			if (err) {
3831 				ext4_remove_li_request(elr);
3832 				continue;
3833 			}
3834 			if (!progress) {
3835 				elr->lr_next_sched = jiffies +
3836 					get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3837 			}
3838 			if (!next_wakeup_initialized ||
3839 			    time_before(elr->lr_next_sched, next_wakeup)) {
3840 				next_wakeup = elr->lr_next_sched;
3841 				next_wakeup_initialized = true;
3842 			}
3843 		}
3844 		mutex_unlock(&eli->li_list_mtx);
3845 
3846 		try_to_freeze();
3847 
3848 		cur = jiffies;
3849 		if (!next_wakeup_initialized || time_after_eq(cur, next_wakeup)) {
3850 			cond_resched();
3851 			continue;
3852 		}
3853 
3854 		schedule_timeout_interruptible(next_wakeup - cur);
3855 
3856 		if (kthread_should_stop()) {
3857 			ext4_clear_request_list();
3858 			goto exit_thread;
3859 		}
3860 	}
3861 
3862 exit_thread:
3863 	/*
3864 	 * It looks like the request list is empty, but we need
3865 	 * to check it under the li_list_mtx lock, to prevent any
3866 	 * additions into it, and of course we should lock ext4_li_mtx
3867 	 * to atomically free the list and ext4_li_info, because at
3868 	 * this point another ext4 filesystem could be registering
3869 	 * new one.
3870 	 */
3871 	mutex_lock(&ext4_li_mtx);
3872 	mutex_lock(&eli->li_list_mtx);
3873 	if (!list_empty(&eli->li_request_list)) {
3874 		mutex_unlock(&eli->li_list_mtx);
3875 		mutex_unlock(&ext4_li_mtx);
3876 		goto cont_thread;
3877 	}
3878 	mutex_unlock(&eli->li_list_mtx);
3879 	kfree(ext4_li_info);
3880 	ext4_li_info = NULL;
3881 	mutex_unlock(&ext4_li_mtx);
3882 
3883 	return 0;
3884 }
3885 
3886 static void ext4_clear_request_list(void)
3887 {
3888 	struct list_head *pos, *n;
3889 	struct ext4_li_request *elr;
3890 
3891 	mutex_lock(&ext4_li_info->li_list_mtx);
3892 	list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3893 		elr = list_entry(pos, struct ext4_li_request,
3894 				 lr_request);
3895 		ext4_remove_li_request(elr);
3896 	}
3897 	mutex_unlock(&ext4_li_info->li_list_mtx);
3898 }
3899 
3900 static int ext4_run_lazyinit_thread(void)
3901 {
3902 	ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3903 					 ext4_li_info, "ext4lazyinit");
3904 	if (IS_ERR(ext4_lazyinit_task)) {
3905 		int err = PTR_ERR(ext4_lazyinit_task);
3906 		ext4_clear_request_list();
3907 		kfree(ext4_li_info);
3908 		ext4_li_info = NULL;
3909 		printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3910 				 "initialization thread\n",
3911 				 err);
3912 		return err;
3913 	}
3914 	ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3915 	return 0;
3916 }
3917 
3918 /*
3919  * Check whether it make sense to run itable init. thread or not.
3920  * If there is at least one uninitialized inode table, return
3921  * corresponding group number, else the loop goes through all
3922  * groups and return total number of groups.
3923  */
3924 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3925 {
3926 	ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3927 	struct ext4_group_desc *gdp = NULL;
3928 
3929 	if (!ext4_has_group_desc_csum(sb))
3930 		return ngroups;
3931 
3932 	for (group = 0; group < ngroups; group++) {
3933 		gdp = ext4_get_group_desc(sb, group, NULL);
3934 		if (!gdp)
3935 			continue;
3936 
3937 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3938 			break;
3939 	}
3940 
3941 	return group;
3942 }
3943 
3944 static int ext4_li_info_new(void)
3945 {
3946 	struct ext4_lazy_init *eli = NULL;
3947 
3948 	eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3949 	if (!eli)
3950 		return -ENOMEM;
3951 
3952 	INIT_LIST_HEAD(&eli->li_request_list);
3953 	mutex_init(&eli->li_list_mtx);
3954 
3955 	eli->li_state |= EXT4_LAZYINIT_QUIT;
3956 
3957 	ext4_li_info = eli;
3958 
3959 	return 0;
3960 }
3961 
3962 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3963 					    ext4_group_t start)
3964 {
3965 	struct ext4_li_request *elr;
3966 
3967 	elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3968 	if (!elr)
3969 		return NULL;
3970 
3971 	elr->lr_super = sb;
3972 	elr->lr_first_not_zeroed = start;
3973 	if (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS)) {
3974 		elr->lr_mode = EXT4_LI_MODE_ITABLE;
3975 		elr->lr_next_group = start;
3976 	} else {
3977 		elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3978 	}
3979 
3980 	/*
3981 	 * Randomize first schedule time of the request to
3982 	 * spread the inode table initialization requests
3983 	 * better.
3984 	 */
3985 	elr->lr_next_sched = jiffies + get_random_u32_below(EXT4_DEF_LI_MAX_START_DELAY * HZ);
3986 	return elr;
3987 }
3988 
3989 int ext4_register_li_request(struct super_block *sb,
3990 			     ext4_group_t first_not_zeroed)
3991 {
3992 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3993 	struct ext4_li_request *elr = NULL;
3994 	ext4_group_t ngroups = sbi->s_groups_count;
3995 	int ret = 0;
3996 
3997 	mutex_lock(&ext4_li_mtx);
3998 	if (sbi->s_li_request != NULL) {
3999 		/*
4000 		 * Reset timeout so it can be computed again, because
4001 		 * s_li_wait_mult might have changed.
4002 		 */
4003 		sbi->s_li_request->lr_timeout = 0;
4004 		goto out;
4005 	}
4006 
4007 	if (ext4_emergency_state(sb) || sb_rdonly(sb) ||
4008 	    (test_opt(sb, NO_PREFETCH_BLOCK_BITMAPS) &&
4009 	     (first_not_zeroed == ngroups || !test_opt(sb, INIT_INODE_TABLE))))
4010 		goto out;
4011 
4012 	elr = ext4_li_request_new(sb, first_not_zeroed);
4013 	if (!elr) {
4014 		ret = -ENOMEM;
4015 		goto out;
4016 	}
4017 
4018 	if (NULL == ext4_li_info) {
4019 		ret = ext4_li_info_new();
4020 		if (ret)
4021 			goto out;
4022 	}
4023 
4024 	mutex_lock(&ext4_li_info->li_list_mtx);
4025 	list_add(&elr->lr_request, &ext4_li_info->li_request_list);
4026 	mutex_unlock(&ext4_li_info->li_list_mtx);
4027 
4028 	sbi->s_li_request = elr;
4029 	/*
4030 	 * set elr to NULL here since it has been inserted to
4031 	 * the request_list and the removal and free of it is
4032 	 * handled by ext4_clear_request_list from now on.
4033 	 */
4034 	elr = NULL;
4035 
4036 	if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
4037 		ret = ext4_run_lazyinit_thread();
4038 		if (ret)
4039 			goto out;
4040 	}
4041 out:
4042 	mutex_unlock(&ext4_li_mtx);
4043 	if (ret)
4044 		kfree(elr);
4045 	return ret;
4046 }
4047 
4048 /*
4049  * We do not need to lock anything since this is called on
4050  * module unload.
4051  */
4052 static void ext4_destroy_lazyinit_thread(void)
4053 {
4054 	/*
4055 	 * If thread exited earlier
4056 	 * there's nothing to be done.
4057 	 */
4058 	if (!ext4_li_info || !ext4_lazyinit_task)
4059 		return;
4060 
4061 	kthread_stop(ext4_lazyinit_task);
4062 }
4063 
4064 static int set_journal_csum_feature_set(struct super_block *sb)
4065 {
4066 	int ret = 1;
4067 	int compat, incompat;
4068 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4069 
4070 	if (ext4_has_feature_metadata_csum(sb)) {
4071 		/* journal checksum v3 */
4072 		compat = 0;
4073 		incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
4074 	} else {
4075 		/* journal checksum v1 */
4076 		compat = JBD2_FEATURE_COMPAT_CHECKSUM;
4077 		incompat = 0;
4078 	}
4079 
4080 	jbd2_journal_clear_features(sbi->s_journal,
4081 			JBD2_FEATURE_COMPAT_CHECKSUM, 0,
4082 			JBD2_FEATURE_INCOMPAT_CSUM_V3 |
4083 			JBD2_FEATURE_INCOMPAT_CSUM_V2);
4084 	if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4085 		ret = jbd2_journal_set_features(sbi->s_journal,
4086 				compat, 0,
4087 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
4088 				incompat);
4089 	} else if (test_opt(sb, JOURNAL_CHECKSUM)) {
4090 		ret = jbd2_journal_set_features(sbi->s_journal,
4091 				compat, 0,
4092 				incompat);
4093 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4094 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4095 	} else {
4096 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
4097 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
4098 	}
4099 
4100 	return ret;
4101 }
4102 
4103 /*
4104  * Note: calculating the overhead so we can be compatible with
4105  * historical BSD practice is quite difficult in the face of
4106  * clusters/bigalloc.  This is because multiple metadata blocks from
4107  * different block group can end up in the same allocation cluster.
4108  * Calculating the exact overhead in the face of clustered allocation
4109  * requires either O(all block bitmaps) in memory or O(number of block
4110  * groups**2) in time.  We will still calculate the superblock for
4111  * older file systems --- and if we come across with a bigalloc file
4112  * system with zero in s_overhead_clusters the estimate will be close to
4113  * correct especially for very large cluster sizes --- but for newer
4114  * file systems, it's better to calculate this figure once at mkfs
4115  * time, and store it in the superblock.  If the superblock value is
4116  * present (even for non-bigalloc file systems), we will use it.
4117  */
4118 static int count_overhead(struct super_block *sb, ext4_group_t grp,
4119 			  char *buf)
4120 {
4121 	struct ext4_sb_info	*sbi = EXT4_SB(sb);
4122 	struct ext4_group_desc	*gdp;
4123 	ext4_fsblk_t		first_block, last_block, b;
4124 	ext4_group_t		i, ngroups = ext4_get_groups_count(sb);
4125 	int			s, j, count = 0;
4126 	int			has_super = ext4_bg_has_super(sb, grp);
4127 
4128 	if (!ext4_has_feature_bigalloc(sb))
4129 		return (has_super + ext4_bg_num_gdb(sb, grp) +
4130 			(has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
4131 			sbi->s_itb_per_group + 2);
4132 
4133 	first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
4134 		(grp * EXT4_BLOCKS_PER_GROUP(sb));
4135 	last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
4136 	for (i = 0; i < ngroups; i++) {
4137 		gdp = ext4_get_group_desc(sb, i, NULL);
4138 		b = ext4_block_bitmap(sb, gdp);
4139 		if (b >= first_block && b <= last_block) {
4140 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4141 			count++;
4142 		}
4143 		b = ext4_inode_bitmap(sb, gdp);
4144 		if (b >= first_block && b <= last_block) {
4145 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
4146 			count++;
4147 		}
4148 		b = ext4_inode_table(sb, gdp);
4149 		if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
4150 			for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
4151 				int c = EXT4_B2C(sbi, b - first_block);
4152 				ext4_set_bit(c, buf);
4153 				count++;
4154 			}
4155 		if (i != grp)
4156 			continue;
4157 		s = 0;
4158 		if (ext4_bg_has_super(sb, grp)) {
4159 			ext4_set_bit(s++, buf);
4160 			count++;
4161 		}
4162 		j = ext4_bg_num_gdb(sb, grp);
4163 		if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
4164 			ext4_error(sb, "Invalid number of block group "
4165 				   "descriptor blocks: %d", j);
4166 			j = EXT4_BLOCKS_PER_GROUP(sb) - s;
4167 		}
4168 		count += j;
4169 		for (; j > 0; j--)
4170 			ext4_set_bit(EXT4_B2C(sbi, s++), buf);
4171 	}
4172 	if (!count)
4173 		return 0;
4174 	return EXT4_CLUSTERS_PER_GROUP(sb) -
4175 		ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
4176 }
4177 
4178 /*
4179  * Compute the overhead and stash it in sbi->s_overhead
4180  */
4181 int ext4_calculate_overhead(struct super_block *sb)
4182 {
4183 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4184 	struct ext4_super_block *es = sbi->s_es;
4185 	struct inode *j_inode;
4186 	unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
4187 	ext4_group_t i, ngroups = ext4_get_groups_count(sb);
4188 	ext4_fsblk_t overhead = 0;
4189 	char *buf = (char *) get_zeroed_page(GFP_NOFS);
4190 
4191 	if (!buf)
4192 		return -ENOMEM;
4193 
4194 	/*
4195 	 * Compute the overhead (FS structures).  This is constant
4196 	 * for a given filesystem unless the number of block groups
4197 	 * changes so we cache the previous value until it does.
4198 	 */
4199 
4200 	/*
4201 	 * All of the blocks before first_data_block are overhead
4202 	 */
4203 	overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
4204 
4205 	/*
4206 	 * Add the overhead found in each block group
4207 	 */
4208 	for (i = 0; i < ngroups; i++) {
4209 		int blks;
4210 
4211 		blks = count_overhead(sb, i, buf);
4212 		overhead += blks;
4213 		if (blks)
4214 			memset(buf, 0, PAGE_SIZE);
4215 		cond_resched();
4216 	}
4217 
4218 	/*
4219 	 * Add the internal journal blocks whether the journal has been
4220 	 * loaded or not
4221 	 */
4222 	if (sbi->s_journal && !sbi->s_journal_bdev_file)
4223 		overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
4224 	else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
4225 		/* j_inum for internal journal is non-zero */
4226 		j_inode = ext4_get_journal_inode(sb, j_inum);
4227 		if (!IS_ERR(j_inode)) {
4228 			j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
4229 			overhead += EXT4_NUM_B2C(sbi, j_blocks);
4230 			iput(j_inode);
4231 		} else {
4232 			ext4_msg(sb, KERN_ERR, "can't get journal size");
4233 		}
4234 	}
4235 	sbi->s_overhead = overhead;
4236 	smp_wmb();
4237 	free_page((unsigned long) buf);
4238 	return 0;
4239 }
4240 
4241 static void ext4_set_resv_clusters(struct super_block *sb)
4242 {
4243 	ext4_fsblk_t resv_clusters;
4244 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4245 
4246 	/*
4247 	 * There's no need to reserve anything when we aren't using extents.
4248 	 * The space estimates are exact, there are no unwritten extents,
4249 	 * hole punching doesn't need new metadata... This is needed especially
4250 	 * to keep ext2/3 backward compatibility.
4251 	 */
4252 	if (!ext4_has_feature_extents(sb))
4253 		return;
4254 	/*
4255 	 * By default we reserve 2% or 4096 clusters, whichever is smaller.
4256 	 * This should cover the situations where we can not afford to run
4257 	 * out of space like for example punch hole, or converting
4258 	 * unwritten extents in delalloc path. In most cases such
4259 	 * allocation would require 1, or 2 blocks, higher numbers are
4260 	 * very rare.
4261 	 */
4262 	resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4263 			 sbi->s_cluster_bits);
4264 
4265 	do_div(resv_clusters, 50);
4266 	resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4267 
4268 	atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4269 }
4270 
4271 static const char *ext4_quota_mode(struct super_block *sb)
4272 {
4273 #ifdef CONFIG_QUOTA
4274 	if (!ext4_quota_capable(sb))
4275 		return "none";
4276 
4277 	if (EXT4_SB(sb)->s_journal && ext4_is_quota_journalled(sb))
4278 		return "journalled";
4279 	else
4280 		return "writeback";
4281 #else
4282 	return "disabled";
4283 #endif
4284 }
4285 
4286 static void ext4_setup_csum_trigger(struct super_block *sb,
4287 				    enum ext4_journal_trigger_type type,
4288 				    void (*trigger)(
4289 					struct jbd2_buffer_trigger_type *type,
4290 					struct buffer_head *bh,
4291 					void *mapped_data,
4292 					size_t size))
4293 {
4294 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4295 
4296 	sbi->s_journal_triggers[type].sb = sb;
4297 	sbi->s_journal_triggers[type].tr_triggers.t_frozen = trigger;
4298 }
4299 
4300 static void ext4_free_sbi(struct ext4_sb_info *sbi)
4301 {
4302 	if (!sbi)
4303 		return;
4304 
4305 	kfree(sbi->s_blockgroup_lock);
4306 	fs_put_dax(sbi->s_daxdev, NULL);
4307 	kfree(sbi);
4308 }
4309 
4310 static struct ext4_sb_info *ext4_alloc_sbi(struct super_block *sb)
4311 {
4312 	struct ext4_sb_info *sbi;
4313 
4314 	sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4315 	if (!sbi)
4316 		return NULL;
4317 
4318 	sbi->s_daxdev = fs_dax_get_by_bdev(sb->s_bdev, &sbi->s_dax_part_off,
4319 					   NULL, NULL);
4320 
4321 	sbi->s_blockgroup_lock =
4322 		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4323 
4324 	if (!sbi->s_blockgroup_lock)
4325 		goto err_out;
4326 
4327 	sb->s_fs_info = sbi;
4328 	sbi->s_sb = sb;
4329 	return sbi;
4330 err_out:
4331 	fs_put_dax(sbi->s_daxdev, NULL);
4332 	kfree(sbi);
4333 	return NULL;
4334 }
4335 
4336 static void ext4_set_def_opts(struct super_block *sb,
4337 			      struct ext4_super_block *es)
4338 {
4339 	unsigned long def_mount_opts;
4340 
4341 	/* Set defaults before we parse the mount options */
4342 	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4343 	set_opt(sb, INIT_INODE_TABLE);
4344 	if (def_mount_opts & EXT4_DEFM_DEBUG)
4345 		set_opt(sb, DEBUG);
4346 	if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4347 		set_opt(sb, GRPID);
4348 	if (def_mount_opts & EXT4_DEFM_UID16)
4349 		set_opt(sb, NO_UID32);
4350 	/* xattr user namespace & acls are now defaulted on */
4351 	set_opt(sb, XATTR_USER);
4352 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4353 	set_opt(sb, POSIX_ACL);
4354 #endif
4355 	if (ext4_has_feature_fast_commit(sb))
4356 		set_opt2(sb, JOURNAL_FAST_COMMIT);
4357 	/* don't forget to enable journal_csum when metadata_csum is enabled. */
4358 	if (ext4_has_feature_metadata_csum(sb))
4359 		set_opt(sb, JOURNAL_CHECKSUM);
4360 
4361 	if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4362 		set_opt(sb, JOURNAL_DATA);
4363 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4364 		set_opt(sb, ORDERED_DATA);
4365 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4366 		set_opt(sb, WRITEBACK_DATA);
4367 
4368 	if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_PANIC)
4369 		set_opt(sb, ERRORS_PANIC);
4370 	else if (le16_to_cpu(es->s_errors) == EXT4_ERRORS_CONTINUE)
4371 		set_opt(sb, ERRORS_CONT);
4372 	else
4373 		set_opt(sb, ERRORS_RO);
4374 	/* block_validity enabled by default; disable with noblock_validity */
4375 	set_opt(sb, BLOCK_VALIDITY);
4376 	if (def_mount_opts & EXT4_DEFM_DISCARD)
4377 		set_opt(sb, DISCARD);
4378 
4379 	if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4380 		set_opt(sb, BARRIER);
4381 
4382 	/*
4383 	 * enable delayed allocation by default
4384 	 * Use -o nodelalloc to turn it off
4385 	 */
4386 	if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4387 	    ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4388 		set_opt(sb, DELALLOC);
4389 
4390 	if (sb->s_blocksize <= PAGE_SIZE)
4391 		set_opt(sb, DIOREAD_NOLOCK);
4392 }
4393 
4394 static int ext4_handle_clustersize(struct super_block *sb)
4395 {
4396 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4397 	struct ext4_super_block *es = sbi->s_es;
4398 	int clustersize;
4399 
4400 	/* Handle clustersize */
4401 	clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4402 	if (ext4_has_feature_bigalloc(sb)) {
4403 		if (clustersize < sb->s_blocksize) {
4404 			ext4_msg(sb, KERN_ERR,
4405 				 "cluster size (%d) smaller than "
4406 				 "block size (%lu)", clustersize, sb->s_blocksize);
4407 			return -EINVAL;
4408 		}
4409 		sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4410 			le32_to_cpu(es->s_log_block_size);
4411 	} else {
4412 		if (clustersize != sb->s_blocksize) {
4413 			ext4_msg(sb, KERN_ERR,
4414 				 "fragment/cluster size (%d) != "
4415 				 "block size (%lu)", clustersize, sb->s_blocksize);
4416 			return -EINVAL;
4417 		}
4418 		if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
4419 			ext4_msg(sb, KERN_ERR,
4420 				 "#blocks per group too big: %lu",
4421 				 sbi->s_blocks_per_group);
4422 			return -EINVAL;
4423 		}
4424 		sbi->s_cluster_bits = 0;
4425 	}
4426 	sbi->s_clusters_per_group = le32_to_cpu(es->s_clusters_per_group);
4427 	if (sbi->s_clusters_per_group > sb->s_blocksize * 8) {
4428 		ext4_msg(sb, KERN_ERR, "#clusters per group too big: %lu",
4429 			 sbi->s_clusters_per_group);
4430 		return -EINVAL;
4431 	}
4432 	if (sbi->s_blocks_per_group !=
4433 	    (sbi->s_clusters_per_group * (clustersize / sb->s_blocksize))) {
4434 		ext4_msg(sb, KERN_ERR,
4435 			 "blocks per group (%lu) and clusters per group (%lu) inconsistent",
4436 			 sbi->s_blocks_per_group, sbi->s_clusters_per_group);
4437 		return -EINVAL;
4438 	}
4439 	sbi->s_cluster_ratio = clustersize / sb->s_blocksize;
4440 
4441 	/* Do we have standard group size of clustersize * 8 blocks ? */
4442 	if (sbi->s_blocks_per_group == clustersize << 3)
4443 		set_opt2(sb, STD_GROUP_SIZE);
4444 
4445 	return 0;
4446 }
4447 
4448 /*
4449  * ext4_atomic_write_init: Initializes filesystem min & max atomic write units.
4450  * With non-bigalloc filesystem awu will be based upon filesystem blocksize
4451  * & bdev awu units.
4452  * With bigalloc it will be based upon bigalloc cluster size & bdev awu units.
4453  * @sb: super block
4454  */
4455 static void ext4_atomic_write_init(struct super_block *sb)
4456 {
4457 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4458 	struct block_device *bdev = sb->s_bdev;
4459 	unsigned int clustersize = EXT4_CLUSTER_SIZE(sb);
4460 
4461 	if (!bdev_can_atomic_write(bdev))
4462 		return;
4463 
4464 	if (!ext4_has_feature_extents(sb))
4465 		return;
4466 
4467 	sbi->s_awu_min = max(sb->s_blocksize,
4468 			      bdev_atomic_write_unit_min_bytes(bdev));
4469 	sbi->s_awu_max = min(clustersize,
4470 			      bdev_atomic_write_unit_max_bytes(bdev));
4471 	if (sbi->s_awu_min && sbi->s_awu_max &&
4472 	    sbi->s_awu_min <= sbi->s_awu_max) {
4473 		ext4_msg(sb, KERN_NOTICE, "Supports (experimental) DIO atomic writes awu_min: %u, awu_max: %u",
4474 			 sbi->s_awu_min, sbi->s_awu_max);
4475 	} else {
4476 		sbi->s_awu_min = 0;
4477 		sbi->s_awu_max = 0;
4478 	}
4479 }
4480 
4481 static void ext4_fast_commit_init(struct super_block *sb)
4482 {
4483 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4484 
4485 	/* Initialize fast commit stuff */
4486 	atomic_set(&sbi->s_fc_subtid, 0);
4487 	INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4488 	INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4489 	INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4490 	INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4491 	sbi->s_fc_bytes = 0;
4492 	ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4493 	sbi->s_fc_ineligible_tid = 0;
4494 	mutex_init(&sbi->s_fc_lock);
4495 	memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4496 	sbi->s_fc_replay_state.fc_regions = NULL;
4497 	sbi->s_fc_replay_state.fc_regions_size = 0;
4498 	sbi->s_fc_replay_state.fc_regions_used = 0;
4499 	sbi->s_fc_replay_state.fc_regions_valid = 0;
4500 	sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4501 	sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4502 	sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4503 }
4504 
4505 static int ext4_inode_info_init(struct super_block *sb,
4506 				struct ext4_super_block *es)
4507 {
4508 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4509 
4510 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4511 		sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4512 		sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4513 	} else {
4514 		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4515 		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4516 		if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4517 			ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4518 				 sbi->s_first_ino);
4519 			return -EINVAL;
4520 		}
4521 		if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4522 		    (!is_power_of_2(sbi->s_inode_size)) ||
4523 		    (sbi->s_inode_size > sb->s_blocksize)) {
4524 			ext4_msg(sb, KERN_ERR,
4525 			       "unsupported inode size: %d",
4526 			       sbi->s_inode_size);
4527 			ext4_msg(sb, KERN_ERR, "blocksize: %lu", sb->s_blocksize);
4528 			return -EINVAL;
4529 		}
4530 		/*
4531 		 * i_atime_extra is the last extra field available for
4532 		 * [acm]times in struct ext4_inode. Checking for that
4533 		 * field should suffice to ensure we have extra space
4534 		 * for all three.
4535 		 */
4536 		if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4537 			sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4538 			sb->s_time_gran = 1;
4539 			sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4540 		} else {
4541 			sb->s_time_gran = NSEC_PER_SEC;
4542 			sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4543 		}
4544 		sb->s_time_min = EXT4_TIMESTAMP_MIN;
4545 	}
4546 
4547 	if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4548 		sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4549 			EXT4_GOOD_OLD_INODE_SIZE;
4550 		if (ext4_has_feature_extra_isize(sb)) {
4551 			unsigned v, max = (sbi->s_inode_size -
4552 					   EXT4_GOOD_OLD_INODE_SIZE);
4553 
4554 			v = le16_to_cpu(es->s_want_extra_isize);
4555 			if (v > max) {
4556 				ext4_msg(sb, KERN_ERR,
4557 					 "bad s_want_extra_isize: %d", v);
4558 				return -EINVAL;
4559 			}
4560 			if (sbi->s_want_extra_isize < v)
4561 				sbi->s_want_extra_isize = v;
4562 
4563 			v = le16_to_cpu(es->s_min_extra_isize);
4564 			if (v > max) {
4565 				ext4_msg(sb, KERN_ERR,
4566 					 "bad s_min_extra_isize: %d", v);
4567 				return -EINVAL;
4568 			}
4569 			if (sbi->s_want_extra_isize < v)
4570 				sbi->s_want_extra_isize = v;
4571 		}
4572 	}
4573 
4574 	return 0;
4575 }
4576 
4577 #if IS_ENABLED(CONFIG_UNICODE)
4578 static int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4579 {
4580 	const struct ext4_sb_encodings *encoding_info;
4581 	struct unicode_map *encoding;
4582 	__u16 encoding_flags = le16_to_cpu(es->s_encoding_flags);
4583 
4584 	if (!ext4_has_feature_casefold(sb) || sb->s_encoding)
4585 		return 0;
4586 
4587 	encoding_info = ext4_sb_read_encoding(es);
4588 	if (!encoding_info) {
4589 		ext4_msg(sb, KERN_ERR,
4590 			"Encoding requested by superblock is unknown");
4591 		return -EINVAL;
4592 	}
4593 
4594 	encoding = utf8_load(encoding_info->version);
4595 	if (IS_ERR(encoding)) {
4596 		ext4_msg(sb, KERN_ERR,
4597 			"can't mount with superblock charset: %s-%u.%u.%u "
4598 			"not supported by the kernel. flags: 0x%x.",
4599 			encoding_info->name,
4600 			unicode_major(encoding_info->version),
4601 			unicode_minor(encoding_info->version),
4602 			unicode_rev(encoding_info->version),
4603 			encoding_flags);
4604 		return -EINVAL;
4605 	}
4606 	ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4607 		"%s-%u.%u.%u with flags 0x%hx", encoding_info->name,
4608 		unicode_major(encoding_info->version),
4609 		unicode_minor(encoding_info->version),
4610 		unicode_rev(encoding_info->version),
4611 		encoding_flags);
4612 
4613 	sb->s_encoding = encoding;
4614 	sb->s_encoding_flags = encoding_flags;
4615 
4616 	return 0;
4617 }
4618 #else
4619 static inline int ext4_encoding_init(struct super_block *sb, struct ext4_super_block *es)
4620 {
4621 	return 0;
4622 }
4623 #endif
4624 
4625 static int ext4_init_metadata_csum(struct super_block *sb, struct ext4_super_block *es)
4626 {
4627 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4628 
4629 	/* Warn if metadata_csum and gdt_csum are both set. */
4630 	if (ext4_has_feature_metadata_csum(sb) &&
4631 	    ext4_has_feature_gdt_csum(sb))
4632 		ext4_warning(sb, "metadata_csum and uninit_bg are "
4633 			     "redundant flags; please run fsck.");
4634 
4635 	/* Check for a known checksum algorithm */
4636 	if (!ext4_verify_csum_type(sb, es)) {
4637 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4638 			 "unknown checksum algorithm.");
4639 		return -EINVAL;
4640 	}
4641 	ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
4642 				ext4_orphan_file_block_trigger);
4643 
4644 	/* Check superblock checksum */
4645 	if (!ext4_superblock_csum_verify(sb, es)) {
4646 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4647 			 "invalid superblock checksum.  Run e2fsck?");
4648 		return -EFSBADCRC;
4649 	}
4650 
4651 	/* Precompute checksum seed for all metadata */
4652 	if (ext4_has_feature_csum_seed(sb))
4653 		sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4654 	else if (ext4_has_feature_metadata_csum(sb) ||
4655 		 ext4_has_feature_ea_inode(sb))
4656 		sbi->s_csum_seed = ext4_chksum(~0, es->s_uuid,
4657 					       sizeof(es->s_uuid));
4658 	return 0;
4659 }
4660 
4661 static int ext4_check_feature_compatibility(struct super_block *sb,
4662 					    struct ext4_super_block *es,
4663 					    int silent)
4664 {
4665 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4666 
4667 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4668 	    (ext4_has_compat_features(sb) ||
4669 	     ext4_has_ro_compat_features(sb) ||
4670 	     ext4_has_incompat_features(sb)))
4671 		ext4_msg(sb, KERN_WARNING,
4672 		       "feature flags set on rev 0 fs, "
4673 		       "running e2fsck is recommended");
4674 
4675 	if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4676 		set_opt2(sb, HURD_COMPAT);
4677 		if (ext4_has_feature_64bit(sb)) {
4678 			ext4_msg(sb, KERN_ERR,
4679 				 "The Hurd can't support 64-bit file systems");
4680 			return -EINVAL;
4681 		}
4682 
4683 		/*
4684 		 * ea_inode feature uses l_i_version field which is not
4685 		 * available in HURD_COMPAT mode.
4686 		 */
4687 		if (ext4_has_feature_ea_inode(sb)) {
4688 			ext4_msg(sb, KERN_ERR,
4689 				 "ea_inode feature is not supported for Hurd");
4690 			return -EINVAL;
4691 		}
4692 	}
4693 
4694 	if (IS_EXT2_SB(sb)) {
4695 		if (ext2_feature_set_ok(sb))
4696 			ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4697 				 "using the ext4 subsystem");
4698 		else {
4699 			/*
4700 			 * If we're probing be silent, if this looks like
4701 			 * it's actually an ext[34] filesystem.
4702 			 */
4703 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4704 				return -EINVAL;
4705 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4706 				 "to feature incompatibilities");
4707 			return -EINVAL;
4708 		}
4709 	}
4710 
4711 	if (IS_EXT3_SB(sb)) {
4712 		if (ext3_feature_set_ok(sb))
4713 			ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4714 				 "using the ext4 subsystem");
4715 		else {
4716 			/*
4717 			 * If we're probing be silent, if this looks like
4718 			 * it's actually an ext4 filesystem.
4719 			 */
4720 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4721 				return -EINVAL;
4722 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4723 				 "to feature incompatibilities");
4724 			return -EINVAL;
4725 		}
4726 	}
4727 
4728 	/*
4729 	 * Check feature flags regardless of the revision level, since we
4730 	 * previously didn't change the revision level when setting the flags,
4731 	 * so there is a chance incompat flags are set on a rev 0 filesystem.
4732 	 */
4733 	if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4734 		return -EINVAL;
4735 
4736 	if (sbi->s_daxdev) {
4737 		if (sb->s_blocksize == PAGE_SIZE)
4738 			set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4739 		else
4740 			ext4_msg(sb, KERN_ERR, "unsupported blocksize for DAX\n");
4741 	}
4742 
4743 	if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4744 		if (ext4_has_feature_inline_data(sb)) {
4745 			ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4746 					" that may contain inline data");
4747 			return -EINVAL;
4748 		}
4749 		if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4750 			ext4_msg(sb, KERN_ERR,
4751 				"DAX unsupported by block device.");
4752 			return -EINVAL;
4753 		}
4754 	}
4755 
4756 	if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4757 		ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4758 			 es->s_encryption_level);
4759 		return -EINVAL;
4760 	}
4761 
4762 	return 0;
4763 }
4764 
4765 static int ext4_check_geometry(struct super_block *sb,
4766 			       struct ext4_super_block *es)
4767 {
4768 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4769 	__u64 blocks_count;
4770 	int err;
4771 
4772 	if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (sb->s_blocksize / 4)) {
4773 		ext4_msg(sb, KERN_ERR,
4774 			 "Number of reserved GDT blocks insanely large: %d",
4775 			 le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4776 		return -EINVAL;
4777 	}
4778 	/*
4779 	 * Test whether we have more sectors than will fit in sector_t,
4780 	 * and whether the max offset is addressable by the page cache.
4781 	 */
4782 	err = generic_check_addressable(sb->s_blocksize_bits,
4783 					ext4_blocks_count(es));
4784 	if (err) {
4785 		ext4_msg(sb, KERN_ERR, "filesystem"
4786 			 " too large to mount safely on this system");
4787 		return err;
4788 	}
4789 
4790 	/* check blocks count against device size */
4791 	blocks_count = sb_bdev_nr_blocks(sb);
4792 	if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4793 		ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4794 		       "exceeds size of device (%llu blocks)",
4795 		       ext4_blocks_count(es), blocks_count);
4796 		return -EINVAL;
4797 	}
4798 
4799 	/*
4800 	 * It makes no sense for the first data block to be beyond the end
4801 	 * of the filesystem.
4802 	 */
4803 	if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4804 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4805 			 "block %u is beyond end of filesystem (%llu)",
4806 			 le32_to_cpu(es->s_first_data_block),
4807 			 ext4_blocks_count(es));
4808 		return -EINVAL;
4809 	}
4810 	if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4811 	    (sbi->s_cluster_ratio == 1)) {
4812 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4813 			 "block is 0 with a 1k block and cluster size");
4814 		return -EINVAL;
4815 	}
4816 
4817 	blocks_count = (ext4_blocks_count(es) -
4818 			le32_to_cpu(es->s_first_data_block) +
4819 			EXT4_BLOCKS_PER_GROUP(sb) - 1);
4820 	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4821 	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4822 		ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4823 		       "(block count %llu, first data block %u, "
4824 		       "blocks per group %lu)", blocks_count,
4825 		       ext4_blocks_count(es),
4826 		       le32_to_cpu(es->s_first_data_block),
4827 		       EXT4_BLOCKS_PER_GROUP(sb));
4828 		return -EINVAL;
4829 	}
4830 	sbi->s_groups_count = blocks_count;
4831 	sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4832 			(EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4833 	if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4834 	    le32_to_cpu(es->s_inodes_count)) {
4835 		ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4836 			 le32_to_cpu(es->s_inodes_count),
4837 			 ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4838 		return -EINVAL;
4839 	}
4840 
4841 	return 0;
4842 }
4843 
4844 static int ext4_group_desc_init(struct super_block *sb,
4845 				struct ext4_super_block *es,
4846 				ext4_fsblk_t logical_sb_block,
4847 				ext4_group_t *first_not_zeroed)
4848 {
4849 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4850 	unsigned int db_count;
4851 	ext4_fsblk_t block;
4852 	int i;
4853 
4854 	db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4855 		   EXT4_DESC_PER_BLOCK(sb);
4856 	if (ext4_has_feature_meta_bg(sb)) {
4857 		if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4858 			ext4_msg(sb, KERN_WARNING,
4859 				 "first meta block group too large: %u "
4860 				 "(group descriptor block count %u)",
4861 				 le32_to_cpu(es->s_first_meta_bg), db_count);
4862 			return -EINVAL;
4863 		}
4864 	}
4865 	rcu_assign_pointer(sbi->s_group_desc,
4866 			   kvmalloc_array(db_count,
4867 					  sizeof(struct buffer_head *),
4868 					  GFP_KERNEL));
4869 	if (sbi->s_group_desc == NULL) {
4870 		ext4_msg(sb, KERN_ERR, "not enough memory");
4871 		return -ENOMEM;
4872 	}
4873 
4874 	bgl_lock_init(sbi->s_blockgroup_lock);
4875 
4876 	/* Pre-read the descriptors into the buffer cache */
4877 	for (i = 0; i < db_count; i++) {
4878 		block = descriptor_loc(sb, logical_sb_block, i);
4879 		ext4_sb_breadahead_unmovable(sb, block);
4880 	}
4881 
4882 	for (i = 0; i < db_count; i++) {
4883 		struct buffer_head *bh;
4884 
4885 		block = descriptor_loc(sb, logical_sb_block, i);
4886 		bh = ext4_sb_bread_unmovable(sb, block);
4887 		if (IS_ERR(bh)) {
4888 			ext4_msg(sb, KERN_ERR,
4889 			       "can't read group descriptor %d", i);
4890 			sbi->s_gdb_count = i;
4891 			return PTR_ERR(bh);
4892 		}
4893 		rcu_read_lock();
4894 		rcu_dereference(sbi->s_group_desc)[i] = bh;
4895 		rcu_read_unlock();
4896 	}
4897 	sbi->s_gdb_count = db_count;
4898 	if (!ext4_check_descriptors(sb, logical_sb_block, first_not_zeroed)) {
4899 		ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4900 		return -EFSCORRUPTED;
4901 	}
4902 
4903 	return 0;
4904 }
4905 
4906 static int ext4_load_and_init_journal(struct super_block *sb,
4907 				      struct ext4_super_block *es,
4908 				      struct ext4_fs_context *ctx)
4909 {
4910 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4911 	int err;
4912 
4913 	err = ext4_load_journal(sb, es, ctx->journal_devnum);
4914 	if (err)
4915 		return err;
4916 
4917 	if (ext4_has_feature_64bit(sb) &&
4918 	    !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4919 				       JBD2_FEATURE_INCOMPAT_64BIT)) {
4920 		ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4921 		goto out;
4922 	}
4923 
4924 	if (!set_journal_csum_feature_set(sb)) {
4925 		ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4926 			 "feature set");
4927 		goto out;
4928 	}
4929 
4930 	if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4931 		!jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4932 					  JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4933 		ext4_msg(sb, KERN_ERR,
4934 			"Failed to set fast commit journal feature");
4935 		goto out;
4936 	}
4937 
4938 	/* We have now updated the journal if required, so we can
4939 	 * validate the data journaling mode. */
4940 	switch (test_opt(sb, DATA_FLAGS)) {
4941 	case 0:
4942 		/* No mode set, assume a default based on the journal
4943 		 * capabilities: ORDERED_DATA if the journal can
4944 		 * cope, else JOURNAL_DATA
4945 		 */
4946 		if (jbd2_journal_check_available_features
4947 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4948 			set_opt(sb, ORDERED_DATA);
4949 			sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4950 		} else {
4951 			set_opt(sb, JOURNAL_DATA);
4952 			sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4953 		}
4954 		break;
4955 
4956 	case EXT4_MOUNT_ORDERED_DATA:
4957 	case EXT4_MOUNT_WRITEBACK_DATA:
4958 		if (!jbd2_journal_check_available_features
4959 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4960 			ext4_msg(sb, KERN_ERR, "Journal does not support "
4961 			       "requested data journaling mode");
4962 			goto out;
4963 		}
4964 		break;
4965 	default:
4966 		break;
4967 	}
4968 
4969 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4970 	    test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4971 		ext4_msg(sb, KERN_ERR, "can't mount with "
4972 			"journal_async_commit in data=ordered mode");
4973 		goto out;
4974 	}
4975 
4976 	set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
4977 
4978 	sbi->s_journal->j_submit_inode_data_buffers =
4979 		ext4_journal_submit_inode_data_buffers;
4980 	sbi->s_journal->j_finish_inode_data_buffers =
4981 		ext4_journal_finish_inode_data_buffers;
4982 
4983 	return 0;
4984 
4985 out:
4986 	ext4_journal_destroy(sbi, sbi->s_journal);
4987 	return -EINVAL;
4988 }
4989 
4990 static int ext4_check_journal_data_mode(struct super_block *sb)
4991 {
4992 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4993 		printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with "
4994 			    "data=journal disables delayed allocation, "
4995 			    "dioread_nolock, O_DIRECT and fast_commit support!\n");
4996 		/* can't mount with both data=journal and dioread_nolock. */
4997 		clear_opt(sb, DIOREAD_NOLOCK);
4998 		clear_opt2(sb, JOURNAL_FAST_COMMIT);
4999 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5000 			ext4_msg(sb, KERN_ERR, "can't mount with "
5001 				 "both data=journal and delalloc");
5002 			return -EINVAL;
5003 		}
5004 		if (test_opt(sb, DAX_ALWAYS)) {
5005 			ext4_msg(sb, KERN_ERR, "can't mount with "
5006 				 "both data=journal and dax");
5007 			return -EINVAL;
5008 		}
5009 		if (ext4_has_feature_encrypt(sb)) {
5010 			ext4_msg(sb, KERN_WARNING,
5011 				 "encrypted files will use data=ordered "
5012 				 "instead of data journaling mode");
5013 		}
5014 		if (test_opt(sb, DELALLOC))
5015 			clear_opt(sb, DELALLOC);
5016 	} else {
5017 		sb->s_iflags |= SB_I_CGROUPWB;
5018 	}
5019 
5020 	return 0;
5021 }
5022 
5023 static const char *ext4_has_journal_option(struct super_block *sb)
5024 {
5025 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5026 
5027 	if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
5028 		return "journal_async_commit";
5029 	if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM))
5030 		return "journal_checksum";
5031 	if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
5032 		return "commit=";
5033 	if (EXT4_MOUNT_DATA_FLAGS &
5034 	    (sbi->s_mount_opt ^ sbi->s_def_mount_opt))
5035 		return "data=";
5036 	if (test_opt(sb, DATA_ERR_ABORT))
5037 		return "data_err=abort";
5038 	return NULL;
5039 }
5040 
5041 static int ext4_load_super(struct super_block *sb, ext4_fsblk_t *lsb,
5042 			   int silent)
5043 {
5044 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5045 	struct ext4_super_block *es;
5046 	ext4_fsblk_t logical_sb_block;
5047 	unsigned long offset = 0;
5048 	struct buffer_head *bh;
5049 	int ret = -EINVAL;
5050 	int blocksize;
5051 
5052 	blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
5053 	if (!blocksize) {
5054 		ext4_msg(sb, KERN_ERR, "unable to set blocksize");
5055 		return -EINVAL;
5056 	}
5057 
5058 	/*
5059 	 * The ext4 superblock will not be buffer aligned for other than 1kB
5060 	 * block sizes.  We need to calculate the offset from buffer start.
5061 	 */
5062 	if (blocksize != EXT4_MIN_BLOCK_SIZE) {
5063 		logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5064 		offset = do_div(logical_sb_block, blocksize);
5065 	} else {
5066 		logical_sb_block = sbi->s_sb_block;
5067 	}
5068 
5069 	bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5070 	if (IS_ERR(bh)) {
5071 		ext4_msg(sb, KERN_ERR, "unable to read superblock");
5072 		return PTR_ERR(bh);
5073 	}
5074 	/*
5075 	 * Note: s_es must be initialized as soon as possible because
5076 	 *       some ext4 macro-instructions depend on its value
5077 	 */
5078 	es = (struct ext4_super_block *) (bh->b_data + offset);
5079 	sbi->s_es = es;
5080 	sb->s_magic = le16_to_cpu(es->s_magic);
5081 	if (sb->s_magic != EXT4_SUPER_MAGIC) {
5082 		if (!silent)
5083 			ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5084 		goto out;
5085 	}
5086 
5087 	if (le32_to_cpu(es->s_log_block_size) >
5088 	    (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5089 		ext4_msg(sb, KERN_ERR,
5090 			 "Invalid log block size: %u",
5091 			 le32_to_cpu(es->s_log_block_size));
5092 		goto out;
5093 	}
5094 	if (le32_to_cpu(es->s_log_cluster_size) >
5095 	    (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
5096 		ext4_msg(sb, KERN_ERR,
5097 			 "Invalid log cluster size: %u",
5098 			 le32_to_cpu(es->s_log_cluster_size));
5099 		goto out;
5100 	}
5101 
5102 	blocksize = EXT4_MIN_BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
5103 
5104 	/*
5105 	 * If the default block size is not the same as the real block size,
5106 	 * we need to reload it.
5107 	 */
5108 	if (sb->s_blocksize == blocksize) {
5109 		*lsb = logical_sb_block;
5110 		sbi->s_sbh = bh;
5111 		return 0;
5112 	}
5113 
5114 	/*
5115 	 * bh must be released before kill_bdev(), otherwise
5116 	 * it won't be freed and its page also. kill_bdev()
5117 	 * is called by sb_set_blocksize().
5118 	 */
5119 	brelse(bh);
5120 	/* Validate the filesystem blocksize */
5121 	if (!sb_set_blocksize(sb, blocksize)) {
5122 		ext4_msg(sb, KERN_ERR, "bad block size %d",
5123 				blocksize);
5124 		bh = NULL;
5125 		goto out;
5126 	}
5127 
5128 	logical_sb_block = sbi->s_sb_block * EXT4_MIN_BLOCK_SIZE;
5129 	offset = do_div(logical_sb_block, blocksize);
5130 	bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
5131 	if (IS_ERR(bh)) {
5132 		ext4_msg(sb, KERN_ERR, "Can't read superblock on 2nd try");
5133 		ret = PTR_ERR(bh);
5134 		bh = NULL;
5135 		goto out;
5136 	}
5137 	es = (struct ext4_super_block *)(bh->b_data + offset);
5138 	sbi->s_es = es;
5139 	if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
5140 		ext4_msg(sb, KERN_ERR, "Magic mismatch, very weird!");
5141 		goto out;
5142 	}
5143 	*lsb = logical_sb_block;
5144 	sbi->s_sbh = bh;
5145 	return 0;
5146 out:
5147 	brelse(bh);
5148 	return ret;
5149 }
5150 
5151 static int ext4_hash_info_init(struct super_block *sb)
5152 {
5153 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5154 	struct ext4_super_block *es = sbi->s_es;
5155 	unsigned int i;
5156 
5157 	sbi->s_def_hash_version = es->s_def_hash_version;
5158 
5159 	if (sbi->s_def_hash_version > DX_HASH_LAST) {
5160 		ext4_msg(sb, KERN_ERR,
5161 			 "Invalid default hash set in the superblock");
5162 		return -EINVAL;
5163 	} else if (sbi->s_def_hash_version == DX_HASH_SIPHASH) {
5164 		ext4_msg(sb, KERN_ERR,
5165 			 "SIPHASH is not a valid default hash value");
5166 		return -EINVAL;
5167 	}
5168 
5169 	for (i = 0; i < 4; i++)
5170 		sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
5171 
5172 	if (ext4_has_feature_dir_index(sb)) {
5173 		i = le32_to_cpu(es->s_flags);
5174 		if (i & EXT2_FLAGS_UNSIGNED_HASH)
5175 			sbi->s_hash_unsigned = 3;
5176 		else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
5177 #ifdef __CHAR_UNSIGNED__
5178 			if (!sb_rdonly(sb))
5179 				es->s_flags |=
5180 					cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
5181 			sbi->s_hash_unsigned = 3;
5182 #else
5183 			if (!sb_rdonly(sb))
5184 				es->s_flags |=
5185 					cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
5186 #endif
5187 		}
5188 	}
5189 	return 0;
5190 }
5191 
5192 static int ext4_block_group_meta_init(struct super_block *sb, int silent)
5193 {
5194 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5195 	struct ext4_super_block *es = sbi->s_es;
5196 	int has_huge_files;
5197 
5198 	has_huge_files = ext4_has_feature_huge_file(sb);
5199 	sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
5200 						      has_huge_files);
5201 	sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
5202 
5203 	sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
5204 	if (ext4_has_feature_64bit(sb)) {
5205 		if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
5206 		    sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
5207 		    !is_power_of_2(sbi->s_desc_size)) {
5208 			ext4_msg(sb, KERN_ERR,
5209 			       "unsupported descriptor size %lu",
5210 			       sbi->s_desc_size);
5211 			return -EINVAL;
5212 		}
5213 	} else
5214 		sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
5215 
5216 	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
5217 	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
5218 
5219 	sbi->s_inodes_per_block = sb->s_blocksize / EXT4_INODE_SIZE(sb);
5220 	if (sbi->s_inodes_per_block == 0 || sbi->s_blocks_per_group == 0) {
5221 		if (!silent)
5222 			ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5223 		return -EINVAL;
5224 	}
5225 	if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
5226 	    sbi->s_inodes_per_group > sb->s_blocksize * 8) {
5227 		ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
5228 			 sbi->s_inodes_per_group);
5229 		return -EINVAL;
5230 	}
5231 	sbi->s_itb_per_group = sbi->s_inodes_per_group /
5232 					sbi->s_inodes_per_block;
5233 	sbi->s_desc_per_block = sb->s_blocksize / EXT4_DESC_SIZE(sb);
5234 	sbi->s_mount_state = le16_to_cpu(es->s_state) & ~EXT4_FC_REPLAY;
5235 	sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
5236 	sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
5237 
5238 	return 0;
5239 }
5240 
5241 /*
5242  * It's hard to get stripe aligned blocks if stripe is not aligned with
5243  * cluster, just disable stripe and alert user to simplify code and avoid
5244  * stripe aligned allocation which will rarely succeed.
5245  */
5246 static bool ext4_is_stripe_incompatible(struct super_block *sb, unsigned long stripe)
5247 {
5248 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5249 	return (stripe > 0 && sbi->s_cluster_ratio > 1 &&
5250 		stripe % sbi->s_cluster_ratio != 0);
5251 }
5252 
5253 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
5254 {
5255 	struct ext4_super_block *es = NULL;
5256 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5257 	ext4_fsblk_t logical_sb_block;
5258 	struct inode *root;
5259 	int needs_recovery;
5260 	int err;
5261 	ext4_group_t first_not_zeroed;
5262 	struct ext4_fs_context *ctx = fc->fs_private;
5263 	int silent = fc->sb_flags & SB_SILENT;
5264 
5265 	/* Set defaults for the variables that will be set during parsing */
5266 	if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO))
5267 		ctx->journal_ioprio = EXT4_DEF_JOURNAL_IOPRIO;
5268 
5269 	sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
5270 	sbi->s_sectors_written_start =
5271 		part_stat_read(sb->s_bdev, sectors[STAT_WRITE]);
5272 
5273 	err = ext4_load_super(sb, &logical_sb_block, silent);
5274 	if (err)
5275 		goto out_fail;
5276 
5277 	es = sbi->s_es;
5278 	sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
5279 
5280 	err = ext4_init_metadata_csum(sb, es);
5281 	if (err)
5282 		goto failed_mount;
5283 
5284 	ext4_set_def_opts(sb, es);
5285 
5286 	sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
5287 	sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
5288 	sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
5289 	sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
5290 	sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
5291 	sbi->s_sb_update_kb = EXT4_DEF_SB_UPDATE_INTERVAL_KB;
5292 	sbi->s_sb_update_sec = EXT4_DEF_SB_UPDATE_INTERVAL_SEC;
5293 
5294 	/*
5295 	 * set default s_li_wait_mult for lazyinit, for the case there is
5296 	 * no mount option specified.
5297 	 */
5298 	sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
5299 
5300 	err = ext4_inode_info_init(sb, es);
5301 	if (err)
5302 		goto failed_mount;
5303 
5304 	err = parse_apply_sb_mount_options(sb, ctx);
5305 	if (err < 0)
5306 		goto failed_mount;
5307 
5308 	sbi->s_def_mount_opt = sbi->s_mount_opt;
5309 	sbi->s_def_mount_opt2 = sbi->s_mount_opt2;
5310 
5311 	err = ext4_check_opt_consistency(fc, sb);
5312 	if (err < 0)
5313 		goto failed_mount;
5314 
5315 	ext4_apply_options(fc, sb);
5316 
5317 	err = ext4_encoding_init(sb, es);
5318 	if (err)
5319 		goto failed_mount;
5320 
5321 	err = ext4_check_journal_data_mode(sb);
5322 	if (err)
5323 		goto failed_mount;
5324 
5325 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5326 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5327 
5328 	/* HSM events are allowed by default. */
5329 	sb->s_iflags |= SB_I_ALLOW_HSM;
5330 
5331 	err = ext4_check_feature_compatibility(sb, es, silent);
5332 	if (err)
5333 		goto failed_mount;
5334 
5335 	err = ext4_block_group_meta_init(sb, silent);
5336 	if (err)
5337 		goto failed_mount;
5338 
5339 	err = ext4_hash_info_init(sb);
5340 	if (err)
5341 		goto failed_mount;
5342 
5343 	err = ext4_handle_clustersize(sb);
5344 	if (err)
5345 		goto failed_mount;
5346 
5347 	err = ext4_check_geometry(sb, es);
5348 	if (err)
5349 		goto failed_mount;
5350 
5351 	timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
5352 	spin_lock_init(&sbi->s_error_lock);
5353 	INIT_WORK(&sbi->s_sb_upd_work, update_super_work);
5354 
5355 	err = ext4_group_desc_init(sb, es, logical_sb_block, &first_not_zeroed);
5356 	if (err)
5357 		goto failed_mount3;
5358 
5359 	err = ext4_es_register_shrinker(sbi);
5360 	if (err)
5361 		goto failed_mount3;
5362 
5363 	sbi->s_stripe = ext4_get_stripe_size(sbi);
5364 	if (ext4_is_stripe_incompatible(sb, sbi->s_stripe)) {
5365 		ext4_msg(sb, KERN_WARNING,
5366 			 "stripe (%lu) is not aligned with cluster size (%u), "
5367 			 "stripe is disabled",
5368 			 sbi->s_stripe, sbi->s_cluster_ratio);
5369 		sbi->s_stripe = 0;
5370 	}
5371 	sbi->s_extent_max_zeroout_kb = 32;
5372 
5373 	/*
5374 	 * set up enough so that it can read an inode
5375 	 */
5376 	sb->s_op = &ext4_sops;
5377 	sb->s_export_op = &ext4_export_ops;
5378 	sb->s_xattr = ext4_xattr_handlers;
5379 #ifdef CONFIG_FS_ENCRYPTION
5380 	sb->s_cop = &ext4_cryptops;
5381 #endif
5382 #ifdef CONFIG_FS_VERITY
5383 	sb->s_vop = &ext4_verityops;
5384 #endif
5385 #ifdef CONFIG_QUOTA
5386 	sb->dq_op = &ext4_quota_operations;
5387 	if (ext4_has_feature_quota(sb))
5388 		sb->s_qcop = &dquot_quotactl_sysfile_ops;
5389 	else
5390 		sb->s_qcop = &ext4_qctl_operations;
5391 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
5392 #endif
5393 	super_set_uuid(sb, es->s_uuid, sizeof(es->s_uuid));
5394 	super_set_sysfs_name_bdev(sb);
5395 
5396 	INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
5397 	mutex_init(&sbi->s_orphan_lock);
5398 
5399 	spin_lock_init(&sbi->s_bdev_wb_lock);
5400 
5401 	ext4_atomic_write_init(sb);
5402 	ext4_fast_commit_init(sb);
5403 
5404 	sb->s_root = NULL;
5405 
5406 	needs_recovery = (es->s_last_orphan != 0 ||
5407 			  ext4_has_feature_orphan_present(sb) ||
5408 			  ext4_has_feature_journal_needs_recovery(sb));
5409 
5410 	if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb)) {
5411 		err = ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block));
5412 		if (err)
5413 			goto failed_mount3a;
5414 	}
5415 
5416 	err = -EINVAL;
5417 	/*
5418 	 * The first inode we look at is the journal inode.  Don't try
5419 	 * root first: it may be modified in the journal!
5420 	 */
5421 	if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
5422 		err = ext4_load_and_init_journal(sb, es, ctx);
5423 		if (err)
5424 			goto failed_mount3a;
5425 		if (bdev_read_only(sb->s_bdev))
5426 		    needs_recovery = 0;
5427 	} else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
5428 		   ext4_has_feature_journal_needs_recovery(sb)) {
5429 		ext4_msg(sb, KERN_ERR, "required journal recovery "
5430 		       "suppressed and not mounted read-only");
5431 		goto failed_mount3a;
5432 	} else {
5433 		const char *journal_option;
5434 
5435 		/* Nojournal mode, all journal mount options are illegal */
5436 		journal_option = ext4_has_journal_option(sb);
5437 		if (journal_option != NULL) {
5438 			ext4_msg(sb, KERN_ERR,
5439 				 "can't mount with %s, fs mounted w/o journal",
5440 				 journal_option);
5441 			goto failed_mount3a;
5442 		}
5443 
5444 		sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
5445 		clear_opt(sb, JOURNAL_CHECKSUM);
5446 		clear_opt(sb, DATA_FLAGS);
5447 		clear_opt2(sb, JOURNAL_FAST_COMMIT);
5448 		sbi->s_journal = NULL;
5449 		needs_recovery = 0;
5450 	}
5451 
5452 	if (!test_opt(sb, NO_MBCACHE)) {
5453 		sbi->s_ea_block_cache = ext4_xattr_create_cache();
5454 		if (!sbi->s_ea_block_cache) {
5455 			ext4_msg(sb, KERN_ERR,
5456 				 "Failed to create ea_block_cache");
5457 			err = -EINVAL;
5458 			goto failed_mount_wq;
5459 		}
5460 
5461 		if (ext4_has_feature_ea_inode(sb)) {
5462 			sbi->s_ea_inode_cache = ext4_xattr_create_cache();
5463 			if (!sbi->s_ea_inode_cache) {
5464 				ext4_msg(sb, KERN_ERR,
5465 					 "Failed to create ea_inode_cache");
5466 				err = -EINVAL;
5467 				goto failed_mount_wq;
5468 			}
5469 		}
5470 	}
5471 
5472 	/*
5473 	 * Get the # of file system overhead blocks from the
5474 	 * superblock if present.
5475 	 */
5476 	sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
5477 	/* ignore the precalculated value if it is ridiculous */
5478 	if (sbi->s_overhead > ext4_blocks_count(es))
5479 		sbi->s_overhead = 0;
5480 	/*
5481 	 * If the bigalloc feature is not enabled recalculating the
5482 	 * overhead doesn't take long, so we might as well just redo
5483 	 * it to make sure we are using the correct value.
5484 	 */
5485 	if (!ext4_has_feature_bigalloc(sb))
5486 		sbi->s_overhead = 0;
5487 	if (sbi->s_overhead == 0) {
5488 		err = ext4_calculate_overhead(sb);
5489 		if (err)
5490 			goto failed_mount_wq;
5491 	}
5492 
5493 	/*
5494 	 * The maximum number of concurrent works can be high and
5495 	 * concurrency isn't really necessary.  Limit it to 1.
5496 	 */
5497 	EXT4_SB(sb)->rsv_conversion_wq =
5498 		alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
5499 	if (!EXT4_SB(sb)->rsv_conversion_wq) {
5500 		printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
5501 		err = -ENOMEM;
5502 		goto failed_mount4;
5503 	}
5504 
5505 	/*
5506 	 * The jbd2_journal_load will have done any necessary log recovery,
5507 	 * so we can safely mount the rest of the filesystem now.
5508 	 */
5509 
5510 	root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
5511 	if (IS_ERR(root)) {
5512 		ext4_msg(sb, KERN_ERR, "get root inode failed");
5513 		err = PTR_ERR(root);
5514 		root = NULL;
5515 		goto failed_mount4;
5516 	}
5517 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
5518 		ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
5519 		iput(root);
5520 		err = -EFSCORRUPTED;
5521 		goto failed_mount4;
5522 	}
5523 
5524 	generic_set_sb_d_ops(sb);
5525 	sb->s_root = d_make_root(root);
5526 	if (!sb->s_root) {
5527 		ext4_msg(sb, KERN_ERR, "get root dentry failed");
5528 		err = -ENOMEM;
5529 		goto failed_mount4;
5530 	}
5531 
5532 	err = ext4_setup_super(sb, es, sb_rdonly(sb));
5533 	if (err == -EROFS) {
5534 		sb->s_flags |= SB_RDONLY;
5535 	} else if (err)
5536 		goto failed_mount4a;
5537 
5538 	ext4_set_resv_clusters(sb);
5539 
5540 	if (test_opt(sb, BLOCK_VALIDITY)) {
5541 		err = ext4_setup_system_zone(sb);
5542 		if (err) {
5543 			ext4_msg(sb, KERN_ERR, "failed to initialize system "
5544 				 "zone (%d)", err);
5545 			goto failed_mount4a;
5546 		}
5547 	}
5548 	ext4_fc_replay_cleanup(sb);
5549 
5550 	ext4_ext_init(sb);
5551 
5552 	/*
5553 	 * Enable optimize_scan if number of groups is > threshold. This can be
5554 	 * turned off by passing "mb_optimize_scan=0". This can also be
5555 	 * turned on forcefully by passing "mb_optimize_scan=1".
5556 	 */
5557 	if (!(ctx->spec & EXT4_SPEC_mb_optimize_scan)) {
5558 		if (sbi->s_groups_count >= MB_DEFAULT_LINEAR_SCAN_THRESHOLD)
5559 			set_opt2(sb, MB_OPTIMIZE_SCAN);
5560 		else
5561 			clear_opt2(sb, MB_OPTIMIZE_SCAN);
5562 	}
5563 
5564 	err = ext4_mb_init(sb);
5565 	if (err) {
5566 		ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5567 			 err);
5568 		goto failed_mount5;
5569 	}
5570 
5571 	/*
5572 	 * We can only set up the journal commit callback once
5573 	 * mballoc is initialized
5574 	 */
5575 	if (sbi->s_journal)
5576 		sbi->s_journal->j_commit_callback =
5577 			ext4_journal_commit_callback;
5578 
5579 	err = ext4_percpu_param_init(sbi);
5580 	if (err)
5581 		goto failed_mount6;
5582 
5583 	if (ext4_has_feature_flex_bg(sb))
5584 		if (!ext4_fill_flex_info(sb)) {
5585 			ext4_msg(sb, KERN_ERR,
5586 			       "unable to initialize "
5587 			       "flex_bg meta info!");
5588 			err = -ENOMEM;
5589 			goto failed_mount6;
5590 		}
5591 
5592 	err = ext4_register_li_request(sb, first_not_zeroed);
5593 	if (err)
5594 		goto failed_mount6;
5595 
5596 	err = ext4_init_orphan_info(sb);
5597 	if (err)
5598 		goto failed_mount7;
5599 #ifdef CONFIG_QUOTA
5600 	/* Enable quota usage during mount. */
5601 	if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5602 		err = ext4_enable_quotas(sb);
5603 		if (err)
5604 			goto failed_mount8;
5605 	}
5606 #endif  /* CONFIG_QUOTA */
5607 
5608 	/*
5609 	 * Save the original bdev mapping's wb_err value which could be
5610 	 * used to detect the metadata async write error.
5611 	 */
5612 	errseq_check_and_advance(&sb->s_bdev->bd_mapping->wb_err,
5613 				 &sbi->s_bdev_wb_err);
5614 	EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5615 	ext4_orphan_cleanup(sb, es);
5616 	EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5617 	/*
5618 	 * Update the checksum after updating free space/inode counters and
5619 	 * ext4_orphan_cleanup. Otherwise the superblock can have an incorrect
5620 	 * checksum in the buffer cache until it is written out and
5621 	 * e2fsprogs programs trying to open a file system immediately
5622 	 * after it is mounted can fail.
5623 	 */
5624 	ext4_superblock_csum_set(sb);
5625 	if (needs_recovery) {
5626 		ext4_msg(sb, KERN_INFO, "recovery complete");
5627 		err = ext4_mark_recovery_complete(sb, es);
5628 		if (err)
5629 			goto failed_mount9;
5630 	}
5631 
5632 	if (test_opt(sb, DISCARD) && !bdev_max_discard_sectors(sb->s_bdev)) {
5633 		ext4_msg(sb, KERN_WARNING,
5634 			 "mounting with \"discard\" option, but the device does not support discard");
5635 		clear_opt(sb, DISCARD);
5636 	}
5637 
5638 	if (es->s_error_count)
5639 		mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5640 
5641 	/* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5642 	ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5643 	ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5644 	ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5645 	atomic_set(&sbi->s_warning_count, 0);
5646 	atomic_set(&sbi->s_msg_count, 0);
5647 
5648 	/* Register sysfs after all initializations are complete. */
5649 	err = ext4_register_sysfs(sb);
5650 	if (err)
5651 		goto failed_mount9;
5652 
5653 	return 0;
5654 
5655 failed_mount9:
5656 	ext4_quotas_off(sb, EXT4_MAXQUOTAS);
5657 failed_mount8: __maybe_unused
5658 	ext4_release_orphan_info(sb);
5659 failed_mount7:
5660 	ext4_unregister_li_request(sb);
5661 failed_mount6:
5662 	ext4_mb_release(sb);
5663 	ext4_flex_groups_free(sbi);
5664 	ext4_percpu_param_destroy(sbi);
5665 failed_mount5:
5666 	ext4_ext_release(sb);
5667 	ext4_release_system_zone(sb);
5668 failed_mount4a:
5669 	dput(sb->s_root);
5670 	sb->s_root = NULL;
5671 failed_mount4:
5672 	ext4_msg(sb, KERN_ERR, "mount failed");
5673 	if (EXT4_SB(sb)->rsv_conversion_wq)
5674 		destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5675 failed_mount_wq:
5676 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5677 	sbi->s_ea_inode_cache = NULL;
5678 
5679 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5680 	sbi->s_ea_block_cache = NULL;
5681 
5682 	if (sbi->s_journal) {
5683 		ext4_journal_destroy(sbi, sbi->s_journal);
5684 	}
5685 failed_mount3a:
5686 	ext4_es_unregister_shrinker(sbi);
5687 failed_mount3:
5688 	/* flush s_sb_upd_work before sbi destroy */
5689 	flush_work(&sbi->s_sb_upd_work);
5690 	ext4_stop_mmpd(sbi);
5691 	timer_delete_sync(&sbi->s_err_report);
5692 	ext4_group_desc_free(sbi);
5693 failed_mount:
5694 #if IS_ENABLED(CONFIG_UNICODE)
5695 	utf8_unload(sb->s_encoding);
5696 #endif
5697 
5698 #ifdef CONFIG_QUOTA
5699 	for (unsigned int i = 0; i < EXT4_MAXQUOTAS; i++)
5700 		kfree(get_qf_name(sb, sbi, i));
5701 #endif
5702 	fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5703 	brelse(sbi->s_sbh);
5704 	if (sbi->s_journal_bdev_file) {
5705 		invalidate_bdev(file_bdev(sbi->s_journal_bdev_file));
5706 		bdev_fput(sbi->s_journal_bdev_file);
5707 	}
5708 out_fail:
5709 	invalidate_bdev(sb->s_bdev);
5710 	sb->s_fs_info = NULL;
5711 	return err;
5712 }
5713 
5714 static int ext4_fill_super(struct super_block *sb, struct fs_context *fc)
5715 {
5716 	struct ext4_fs_context *ctx = fc->fs_private;
5717 	struct ext4_sb_info *sbi;
5718 	const char *descr;
5719 	int ret;
5720 
5721 	sbi = ext4_alloc_sbi(sb);
5722 	if (!sbi)
5723 		return -ENOMEM;
5724 
5725 	fc->s_fs_info = sbi;
5726 
5727 	/* Cleanup superblock name */
5728 	strreplace(sb->s_id, '/', '!');
5729 
5730 	sbi->s_sb_block = 1;	/* Default super block location */
5731 	if (ctx->spec & EXT4_SPEC_s_sb_block)
5732 		sbi->s_sb_block = ctx->s_sb_block;
5733 
5734 	ret = __ext4_fill_super(fc, sb);
5735 	if (ret < 0)
5736 		goto free_sbi;
5737 
5738 	if (sbi->s_journal) {
5739 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5740 			descr = " journalled data mode";
5741 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5742 			descr = " ordered data mode";
5743 		else
5744 			descr = " writeback data mode";
5745 	} else
5746 		descr = "out journal";
5747 
5748 	if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5749 		ext4_msg(sb, KERN_INFO, "mounted filesystem %pU %s with%s. "
5750 			 "Quota mode: %s.", &sb->s_uuid,
5751 			 sb_rdonly(sb) ? "ro" : "r/w", descr,
5752 			 ext4_quota_mode(sb));
5753 
5754 	/* Update the s_overhead_clusters if necessary */
5755 	ext4_update_overhead(sb, false);
5756 	return 0;
5757 
5758 free_sbi:
5759 	ext4_free_sbi(sbi);
5760 	fc->s_fs_info = NULL;
5761 	return ret;
5762 }
5763 
5764 static int ext4_get_tree(struct fs_context *fc)
5765 {
5766 	return get_tree_bdev(fc, ext4_fill_super);
5767 }
5768 
5769 /*
5770  * Setup any per-fs journal parameters now.  We'll do this both on
5771  * initial mount, once the journal has been initialised but before we've
5772  * done any recovery; and again on any subsequent remount.
5773  */
5774 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5775 {
5776 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5777 
5778 	journal->j_commit_interval = sbi->s_commit_interval;
5779 	journal->j_min_batch_time = sbi->s_min_batch_time;
5780 	journal->j_max_batch_time = sbi->s_max_batch_time;
5781 	ext4_fc_init(sb, journal);
5782 
5783 	write_lock(&journal->j_state_lock);
5784 	if (test_opt(sb, BARRIER))
5785 		journal->j_flags |= JBD2_BARRIER;
5786 	else
5787 		journal->j_flags &= ~JBD2_BARRIER;
5788 	/*
5789 	 * Always enable journal cycle record option, letting the journal
5790 	 * records log transactions continuously between each mount.
5791 	 */
5792 	journal->j_flags |= JBD2_CYCLE_RECORD;
5793 	write_unlock(&journal->j_state_lock);
5794 }
5795 
5796 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5797 					     unsigned int journal_inum)
5798 {
5799 	struct inode *journal_inode;
5800 
5801 	/*
5802 	 * Test for the existence of a valid inode on disk.  Bad things
5803 	 * happen if we iget() an unused inode, as the subsequent iput()
5804 	 * will try to delete it.
5805 	 */
5806 	journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5807 	if (IS_ERR(journal_inode)) {
5808 		ext4_msg(sb, KERN_ERR, "no journal found");
5809 		return ERR_CAST(journal_inode);
5810 	}
5811 	if (!journal_inode->i_nlink) {
5812 		make_bad_inode(journal_inode);
5813 		iput(journal_inode);
5814 		ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5815 		return ERR_PTR(-EFSCORRUPTED);
5816 	}
5817 	if (!S_ISREG(journal_inode->i_mode) || IS_ENCRYPTED(journal_inode)) {
5818 		ext4_msg(sb, KERN_ERR, "invalid journal inode");
5819 		iput(journal_inode);
5820 		return ERR_PTR(-EFSCORRUPTED);
5821 	}
5822 
5823 	ext4_debug("Journal inode found at %p: %lld bytes\n",
5824 		  journal_inode, journal_inode->i_size);
5825 	return journal_inode;
5826 }
5827 
5828 static int ext4_journal_bmap(journal_t *journal, sector_t *block)
5829 {
5830 	struct ext4_map_blocks map;
5831 	int ret;
5832 
5833 	if (journal->j_inode == NULL)
5834 		return 0;
5835 
5836 	map.m_lblk = *block;
5837 	map.m_len = 1;
5838 	ret = ext4_map_blocks(NULL, journal->j_inode, &map, 0);
5839 	if (ret <= 0) {
5840 		ext4_msg(journal->j_inode->i_sb, KERN_CRIT,
5841 			 "journal bmap failed: block %llu ret %d\n",
5842 			 *block, ret);
5843 		jbd2_journal_abort(journal, ret ? ret : -EIO);
5844 		return ret;
5845 	}
5846 	*block = map.m_pblk;
5847 	return 0;
5848 }
5849 
5850 static journal_t *ext4_open_inode_journal(struct super_block *sb,
5851 					  unsigned int journal_inum)
5852 {
5853 	struct inode *journal_inode;
5854 	journal_t *journal;
5855 
5856 	journal_inode = ext4_get_journal_inode(sb, journal_inum);
5857 	if (IS_ERR(journal_inode))
5858 		return ERR_CAST(journal_inode);
5859 
5860 	journal = jbd2_journal_init_inode(journal_inode);
5861 	if (IS_ERR(journal)) {
5862 		ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5863 		iput(journal_inode);
5864 		return ERR_CAST(journal);
5865 	}
5866 	journal->j_private = sb;
5867 	journal->j_bmap = ext4_journal_bmap;
5868 	ext4_init_journal_params(sb, journal);
5869 	return journal;
5870 }
5871 
5872 static struct file *ext4_get_journal_blkdev(struct super_block *sb,
5873 					dev_t j_dev, ext4_fsblk_t *j_start,
5874 					ext4_fsblk_t *j_len)
5875 {
5876 	struct buffer_head *bh;
5877 	struct block_device *bdev;
5878 	struct file *bdev_file;
5879 	int hblock, blocksize;
5880 	ext4_fsblk_t sb_block;
5881 	unsigned long offset;
5882 	struct ext4_super_block *es;
5883 	int errno;
5884 
5885 	bdev_file = bdev_file_open_by_dev(j_dev,
5886 		BLK_OPEN_READ | BLK_OPEN_WRITE | BLK_OPEN_RESTRICT_WRITES,
5887 		sb, &fs_holder_ops);
5888 	if (IS_ERR(bdev_file)) {
5889 		ext4_msg(sb, KERN_ERR,
5890 			 "failed to open journal device unknown-block(%u,%u) %ld",
5891 			 MAJOR(j_dev), MINOR(j_dev), PTR_ERR(bdev_file));
5892 		return bdev_file;
5893 	}
5894 
5895 	bdev = file_bdev(bdev_file);
5896 	blocksize = sb->s_blocksize;
5897 	hblock = bdev_logical_block_size(bdev);
5898 	if (blocksize < hblock) {
5899 		ext4_msg(sb, KERN_ERR,
5900 			"blocksize too small for journal device");
5901 		errno = -EINVAL;
5902 		goto out_bdev;
5903 	}
5904 
5905 	sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5906 	offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5907 	set_blocksize(bdev_file, blocksize);
5908 	bh = __bread(bdev, sb_block, blocksize);
5909 	if (!bh) {
5910 		ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5911 		       "external journal");
5912 		errno = -EINVAL;
5913 		goto out_bdev;
5914 	}
5915 
5916 	es = (struct ext4_super_block *) (bh->b_data + offset);
5917 	if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5918 	    !(le32_to_cpu(es->s_feature_incompat) &
5919 	      EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5920 		ext4_msg(sb, KERN_ERR, "external journal has bad superblock");
5921 		errno = -EFSCORRUPTED;
5922 		goto out_bh;
5923 	}
5924 
5925 	if ((le32_to_cpu(es->s_feature_ro_compat) &
5926 	     EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5927 	    es->s_checksum != ext4_superblock_csum(es)) {
5928 		ext4_msg(sb, KERN_ERR, "external journal has corrupt superblock");
5929 		errno = -EFSCORRUPTED;
5930 		goto out_bh;
5931 	}
5932 
5933 	if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5934 		ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5935 		errno = -EFSCORRUPTED;
5936 		goto out_bh;
5937 	}
5938 
5939 	*j_start = sb_block + 1;
5940 	*j_len = ext4_blocks_count(es);
5941 	brelse(bh);
5942 	return bdev_file;
5943 
5944 out_bh:
5945 	brelse(bh);
5946 out_bdev:
5947 	bdev_fput(bdev_file);
5948 	return ERR_PTR(errno);
5949 }
5950 
5951 static journal_t *ext4_open_dev_journal(struct super_block *sb,
5952 					dev_t j_dev)
5953 {
5954 	journal_t *journal;
5955 	ext4_fsblk_t j_start;
5956 	ext4_fsblk_t j_len;
5957 	struct file *bdev_file;
5958 	int errno = 0;
5959 
5960 	bdev_file = ext4_get_journal_blkdev(sb, j_dev, &j_start, &j_len);
5961 	if (IS_ERR(bdev_file))
5962 		return ERR_CAST(bdev_file);
5963 
5964 	journal = jbd2_journal_init_dev(file_bdev(bdev_file), sb->s_bdev, j_start,
5965 					j_len, sb->s_blocksize);
5966 	if (IS_ERR(journal)) {
5967 		ext4_msg(sb, KERN_ERR, "failed to create device journal");
5968 		errno = PTR_ERR(journal);
5969 		goto out_bdev;
5970 	}
5971 	if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5972 		ext4_msg(sb, KERN_ERR, "External journal has more than one "
5973 					"user (unsupported) - %d",
5974 			be32_to_cpu(journal->j_superblock->s_nr_users));
5975 		errno = -EINVAL;
5976 		goto out_journal;
5977 	}
5978 	journal->j_private = sb;
5979 	EXT4_SB(sb)->s_journal_bdev_file = bdev_file;
5980 	ext4_init_journal_params(sb, journal);
5981 	return journal;
5982 
5983 out_journal:
5984 	ext4_journal_destroy(EXT4_SB(sb), journal);
5985 out_bdev:
5986 	bdev_fput(bdev_file);
5987 	return ERR_PTR(errno);
5988 }
5989 
5990 static int ext4_load_journal(struct super_block *sb,
5991 			     struct ext4_super_block *es,
5992 			     unsigned long journal_devnum)
5993 {
5994 	journal_t *journal;
5995 	unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5996 	dev_t journal_dev;
5997 	int err = 0;
5998 	int really_read_only;
5999 	int journal_dev_ro;
6000 
6001 	if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
6002 		return -EFSCORRUPTED;
6003 
6004 	if (journal_devnum &&
6005 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
6006 		ext4_msg(sb, KERN_INFO, "external journal device major/minor "
6007 			"numbers have changed");
6008 		journal_dev = new_decode_dev(journal_devnum);
6009 	} else
6010 		journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
6011 
6012 	if (journal_inum && journal_dev) {
6013 		ext4_msg(sb, KERN_ERR,
6014 			 "filesystem has both journal inode and journal device!");
6015 		return -EINVAL;
6016 	}
6017 
6018 	if (journal_inum) {
6019 		journal = ext4_open_inode_journal(sb, journal_inum);
6020 		if (IS_ERR(journal))
6021 			return PTR_ERR(journal);
6022 	} else {
6023 		journal = ext4_open_dev_journal(sb, journal_dev);
6024 		if (IS_ERR(journal))
6025 			return PTR_ERR(journal);
6026 	}
6027 
6028 	journal_dev_ro = bdev_read_only(journal->j_dev);
6029 	really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
6030 
6031 	if (journal_dev_ro && !sb_rdonly(sb)) {
6032 		ext4_msg(sb, KERN_ERR,
6033 			 "journal device read-only, try mounting with '-o ro'");
6034 		err = -EROFS;
6035 		goto err_out;
6036 	}
6037 
6038 	/*
6039 	 * Are we loading a blank journal or performing recovery after a
6040 	 * crash?  For recovery, we need to check in advance whether we
6041 	 * can get read-write access to the device.
6042 	 */
6043 	if (ext4_has_feature_journal_needs_recovery(sb)) {
6044 		if (sb_rdonly(sb)) {
6045 			ext4_msg(sb, KERN_INFO, "INFO: recovery "
6046 					"required on readonly filesystem");
6047 			if (really_read_only) {
6048 				ext4_msg(sb, KERN_ERR, "write access "
6049 					"unavailable, cannot proceed "
6050 					"(try mounting with noload)");
6051 				err = -EROFS;
6052 				goto err_out;
6053 			}
6054 			ext4_msg(sb, KERN_INFO, "write access will "
6055 			       "be enabled during recovery");
6056 		}
6057 	}
6058 
6059 	if (!(journal->j_flags & JBD2_BARRIER))
6060 		ext4_msg(sb, KERN_INFO, "barriers disabled");
6061 
6062 	if (!ext4_has_feature_journal_needs_recovery(sb))
6063 		err = jbd2_journal_wipe(journal, !really_read_only);
6064 	if (!err) {
6065 		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
6066 		__le16 orig_state;
6067 		bool changed = false;
6068 
6069 		if (save)
6070 			memcpy(save, ((char *) es) +
6071 			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
6072 		err = jbd2_journal_load(journal);
6073 		if (save && memcmp(((char *) es) + EXT4_S_ERR_START,
6074 				   save, EXT4_S_ERR_LEN)) {
6075 			memcpy(((char *) es) + EXT4_S_ERR_START,
6076 			       save, EXT4_S_ERR_LEN);
6077 			changed = true;
6078 		}
6079 		kfree(save);
6080 		orig_state = es->s_state;
6081 		es->s_state |= cpu_to_le16(EXT4_SB(sb)->s_mount_state &
6082 					   EXT4_ERROR_FS);
6083 		if (orig_state != es->s_state)
6084 			changed = true;
6085 		/* Write out restored error information to the superblock */
6086 		if (changed && !really_read_only) {
6087 			int err2;
6088 			err2 = ext4_commit_super(sb);
6089 			err = err ? : err2;
6090 		}
6091 	}
6092 
6093 	if (err) {
6094 		ext4_msg(sb, KERN_ERR, "error loading journal");
6095 		goto err_out;
6096 	}
6097 
6098 	EXT4_SB(sb)->s_journal = journal;
6099 	err = ext4_clear_journal_err(sb, es);
6100 	if (err) {
6101 		ext4_journal_destroy(EXT4_SB(sb), journal);
6102 		return err;
6103 	}
6104 
6105 	if (!really_read_only && journal_devnum &&
6106 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
6107 		es->s_journal_dev = cpu_to_le32(journal_devnum);
6108 		ext4_commit_super(sb);
6109 	}
6110 	if (!really_read_only && journal_inum &&
6111 	    journal_inum != le32_to_cpu(es->s_journal_inum)) {
6112 		es->s_journal_inum = cpu_to_le32(journal_inum);
6113 		ext4_commit_super(sb);
6114 	}
6115 
6116 	return 0;
6117 
6118 err_out:
6119 	ext4_journal_destroy(EXT4_SB(sb), journal);
6120 	return err;
6121 }
6122 
6123 /* Copy state of EXT4_SB(sb) into buffer for on-disk superblock */
6124 static void ext4_update_super(struct super_block *sb)
6125 {
6126 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6127 	struct ext4_super_block *es = sbi->s_es;
6128 	struct buffer_head *sbh = sbi->s_sbh;
6129 
6130 	lock_buffer(sbh);
6131 	/*
6132 	 * If the file system is mounted read-only, don't update the
6133 	 * superblock write time.  This avoids updating the superblock
6134 	 * write time when we are mounting the root file system
6135 	 * read/only but we need to replay the journal; at that point,
6136 	 * for people who are east of GMT and who make their clock
6137 	 * tick in localtime for Windows bug-for-bug compatibility,
6138 	 * the clock is set in the future, and this will cause e2fsck
6139 	 * to complain and force a full file system check.
6140 	 */
6141 	if (!sb_rdonly(sb))
6142 		ext4_update_tstamp(es, s_wtime);
6143 	es->s_kbytes_written =
6144 		cpu_to_le64(sbi->s_kbytes_written +
6145 		    ((part_stat_read(sb->s_bdev, sectors[STAT_WRITE]) -
6146 		      sbi->s_sectors_written_start) >> 1));
6147 	if (percpu_counter_initialized(&sbi->s_freeclusters_counter))
6148 		ext4_free_blocks_count_set(es,
6149 			EXT4_C2B(sbi, percpu_counter_sum_positive(
6150 				&sbi->s_freeclusters_counter)));
6151 	if (percpu_counter_initialized(&sbi->s_freeinodes_counter))
6152 		es->s_free_inodes_count =
6153 			cpu_to_le32(percpu_counter_sum_positive(
6154 				&sbi->s_freeinodes_counter));
6155 	/* Copy error information to the on-disk superblock */
6156 	spin_lock(&sbi->s_error_lock);
6157 	if (sbi->s_add_error_count > 0) {
6158 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6159 		if (!es->s_first_error_time && !es->s_first_error_time_hi) {
6160 			__ext4_update_tstamp(&es->s_first_error_time,
6161 					     &es->s_first_error_time_hi,
6162 					     sbi->s_first_error_time);
6163 			strtomem_pad(es->s_first_error_func,
6164 				     sbi->s_first_error_func, 0);
6165 			es->s_first_error_line =
6166 				cpu_to_le32(sbi->s_first_error_line);
6167 			es->s_first_error_ino =
6168 				cpu_to_le32(sbi->s_first_error_ino);
6169 			es->s_first_error_block =
6170 				cpu_to_le64(sbi->s_first_error_block);
6171 			es->s_first_error_errcode =
6172 				ext4_errno_to_code(sbi->s_first_error_code);
6173 		}
6174 		__ext4_update_tstamp(&es->s_last_error_time,
6175 				     &es->s_last_error_time_hi,
6176 				     sbi->s_last_error_time);
6177 		strtomem_pad(es->s_last_error_func, sbi->s_last_error_func, 0);
6178 		es->s_last_error_line = cpu_to_le32(sbi->s_last_error_line);
6179 		es->s_last_error_ino = cpu_to_le32(sbi->s_last_error_ino);
6180 		es->s_last_error_block = cpu_to_le64(sbi->s_last_error_block);
6181 		es->s_last_error_errcode =
6182 				ext4_errno_to_code(sbi->s_last_error_code);
6183 		/*
6184 		 * Start the daily error reporting function if it hasn't been
6185 		 * started already
6186 		 */
6187 		if (!es->s_error_count)
6188 			mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);
6189 		le32_add_cpu(&es->s_error_count, sbi->s_add_error_count);
6190 		sbi->s_add_error_count = 0;
6191 	}
6192 	spin_unlock(&sbi->s_error_lock);
6193 
6194 	ext4_superblock_csum_set(sb);
6195 	unlock_buffer(sbh);
6196 }
6197 
6198 static int ext4_commit_super(struct super_block *sb)
6199 {
6200 	struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
6201 
6202 	if (!sbh)
6203 		return -EINVAL;
6204 
6205 	ext4_update_super(sb);
6206 
6207 	lock_buffer(sbh);
6208 	/* Buffer got discarded which means block device got invalidated */
6209 	if (!buffer_mapped(sbh)) {
6210 		unlock_buffer(sbh);
6211 		return -EIO;
6212 	}
6213 
6214 	if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
6215 		/*
6216 		 * Oh, dear.  A previous attempt to write the
6217 		 * superblock failed.  This could happen because the
6218 		 * USB device was yanked out.  Or it could happen to
6219 		 * be a transient write error and maybe the block will
6220 		 * be remapped.  Nothing we can do but to retry the
6221 		 * write and hope for the best.
6222 		 */
6223 		ext4_msg(sb, KERN_ERR, "previous I/O error to "
6224 		       "superblock detected");
6225 		clear_buffer_write_io_error(sbh);
6226 		set_buffer_uptodate(sbh);
6227 	}
6228 	get_bh(sbh);
6229 	/* Clear potential dirty bit if it was journalled update */
6230 	clear_buffer_dirty(sbh);
6231 	sbh->b_end_io = end_buffer_write_sync;
6232 	submit_bh(REQ_OP_WRITE | REQ_SYNC |
6233 		  (test_opt(sb, BARRIER) ? REQ_FUA : 0), sbh);
6234 	wait_on_buffer(sbh);
6235 	if (buffer_write_io_error(sbh)) {
6236 		ext4_msg(sb, KERN_ERR, "I/O error while writing "
6237 		       "superblock");
6238 		clear_buffer_write_io_error(sbh);
6239 		set_buffer_uptodate(sbh);
6240 		return -EIO;
6241 	}
6242 	return 0;
6243 }
6244 
6245 /*
6246  * Have we just finished recovery?  If so, and if we are mounting (or
6247  * remounting) the filesystem readonly, then we will end up with a
6248  * consistent fs on disk.  Record that fact.
6249  */
6250 static int ext4_mark_recovery_complete(struct super_block *sb,
6251 				       struct ext4_super_block *es)
6252 {
6253 	int err;
6254 	journal_t *journal = EXT4_SB(sb)->s_journal;
6255 
6256 	if (!ext4_has_feature_journal(sb)) {
6257 		if (journal != NULL) {
6258 			ext4_error(sb, "Journal got removed while the fs was "
6259 				   "mounted!");
6260 			return -EFSCORRUPTED;
6261 		}
6262 		return 0;
6263 	}
6264 	jbd2_journal_lock_updates(journal);
6265 	err = jbd2_journal_flush(journal, 0);
6266 	if (err < 0)
6267 		goto out;
6268 
6269 	if (sb_rdonly(sb) && (ext4_has_feature_journal_needs_recovery(sb) ||
6270 	    ext4_has_feature_orphan_present(sb))) {
6271 		if (!ext4_orphan_file_empty(sb)) {
6272 			ext4_error(sb, "Orphan file not empty on read-only fs.");
6273 			err = -EFSCORRUPTED;
6274 			goto out;
6275 		}
6276 		ext4_clear_feature_journal_needs_recovery(sb);
6277 		ext4_clear_feature_orphan_present(sb);
6278 		ext4_commit_super(sb);
6279 	}
6280 out:
6281 	jbd2_journal_unlock_updates(journal);
6282 	return err;
6283 }
6284 
6285 /*
6286  * If we are mounting (or read-write remounting) a filesystem whose journal
6287  * has recorded an error from a previous lifetime, move that error to the
6288  * main filesystem now.
6289  */
6290 static int ext4_clear_journal_err(struct super_block *sb,
6291 				   struct ext4_super_block *es)
6292 {
6293 	journal_t *journal;
6294 	int j_errno;
6295 	const char *errstr;
6296 
6297 	if (!ext4_has_feature_journal(sb)) {
6298 		ext4_error(sb, "Journal got removed while the fs was mounted!");
6299 		return -EFSCORRUPTED;
6300 	}
6301 
6302 	journal = EXT4_SB(sb)->s_journal;
6303 
6304 	/*
6305 	 * Now check for any error status which may have been recorded in the
6306 	 * journal by a prior ext4_error() or ext4_abort()
6307 	 */
6308 
6309 	j_errno = jbd2_journal_errno(journal);
6310 	if (j_errno) {
6311 		char nbuf[16];
6312 
6313 		errstr = ext4_decode_error(sb, j_errno, nbuf);
6314 		ext4_warning(sb, "Filesystem error recorded "
6315 			     "from previous mount: %s", errstr);
6316 
6317 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
6318 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
6319 		j_errno = ext4_commit_super(sb);
6320 		if (j_errno)
6321 			return j_errno;
6322 		ext4_warning(sb, "Marked fs in need of filesystem check.");
6323 
6324 		jbd2_journal_clear_err(journal);
6325 		jbd2_journal_update_sb_errno(journal);
6326 	}
6327 	return 0;
6328 }
6329 
6330 /*
6331  * Force the running and committing transactions to commit,
6332  * and wait on the commit.
6333  */
6334 int ext4_force_commit(struct super_block *sb)
6335 {
6336 	return ext4_journal_force_commit(EXT4_SB(sb)->s_journal);
6337 }
6338 
6339 static int ext4_sync_fs(struct super_block *sb, int wait)
6340 {
6341 	int ret = 0;
6342 	tid_t target;
6343 	bool needs_barrier = false;
6344 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6345 
6346 	ret = ext4_emergency_state(sb);
6347 	if (unlikely(ret))
6348 		return ret;
6349 
6350 	trace_ext4_sync_fs(sb, wait);
6351 	flush_workqueue(sbi->rsv_conversion_wq);
6352 	/*
6353 	 * Writeback quota in non-journalled quota case - journalled quota has
6354 	 * no dirty dquots
6355 	 */
6356 	dquot_writeback_dquots(sb, -1);
6357 	/*
6358 	 * Data writeback is possible w/o journal transaction, so barrier must
6359 	 * being sent at the end of the function. But we can skip it if
6360 	 * transaction_commit will do it for us.
6361 	 */
6362 	if (sbi->s_journal) {
6363 		target = jbd2_get_latest_transaction(sbi->s_journal);
6364 		if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
6365 		    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
6366 			needs_barrier = true;
6367 
6368 		if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
6369 			if (wait)
6370 				ret = jbd2_log_wait_commit(sbi->s_journal,
6371 							   target);
6372 		}
6373 	} else if (wait && test_opt(sb, BARRIER))
6374 		needs_barrier = true;
6375 	if (needs_barrier) {
6376 		int err;
6377 		err = blkdev_issue_flush(sb->s_bdev);
6378 		if (!ret)
6379 			ret = err;
6380 	}
6381 
6382 	return ret;
6383 }
6384 
6385 /*
6386  * LVM calls this function before a (read-only) snapshot is created.  This
6387  * gives us a chance to flush the journal completely and mark the fs clean.
6388  *
6389  * Note that only this function cannot bring a filesystem to be in a clean
6390  * state independently. It relies on upper layer to stop all data & metadata
6391  * modifications.
6392  */
6393 static int ext4_freeze(struct super_block *sb)
6394 {
6395 	int error = 0;
6396 	journal_t *journal = EXT4_SB(sb)->s_journal;
6397 
6398 	if (journal) {
6399 		/* Now we set up the journal barrier. */
6400 		jbd2_journal_lock_updates(journal);
6401 
6402 		/*
6403 		 * Don't clear the needs_recovery flag if we failed to
6404 		 * flush the journal.
6405 		 */
6406 		error = jbd2_journal_flush(journal, 0);
6407 		if (error < 0)
6408 			goto out;
6409 
6410 		/* Journal blocked and flushed, clear needs_recovery flag. */
6411 		ext4_clear_feature_journal_needs_recovery(sb);
6412 		if (ext4_orphan_file_empty(sb))
6413 			ext4_clear_feature_orphan_present(sb);
6414 	}
6415 
6416 	error = ext4_commit_super(sb);
6417 out:
6418 	if (journal)
6419 		/* we rely on upper layer to stop further updates */
6420 		jbd2_journal_unlock_updates(journal);
6421 	return error;
6422 }
6423 
6424 /*
6425  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
6426  * flag here, even though the filesystem is not technically dirty yet.
6427  */
6428 static int ext4_unfreeze(struct super_block *sb)
6429 {
6430 	if (ext4_emergency_state(sb))
6431 		return 0;
6432 
6433 	if (EXT4_SB(sb)->s_journal) {
6434 		/* Reset the needs_recovery flag before the fs is unlocked. */
6435 		ext4_set_feature_journal_needs_recovery(sb);
6436 		if (ext4_has_feature_orphan_file(sb))
6437 			ext4_set_feature_orphan_present(sb);
6438 	}
6439 
6440 	ext4_commit_super(sb);
6441 	return 0;
6442 }
6443 
6444 /*
6445  * Structure to save mount options for ext4_remount's benefit
6446  */
6447 struct ext4_mount_options {
6448 	unsigned long s_mount_opt;
6449 	unsigned long s_mount_opt2;
6450 	kuid_t s_resuid;
6451 	kgid_t s_resgid;
6452 	unsigned long s_commit_interval;
6453 	u32 s_min_batch_time, s_max_batch_time;
6454 #ifdef CONFIG_QUOTA
6455 	int s_jquota_fmt;
6456 	char *s_qf_names[EXT4_MAXQUOTAS];
6457 #endif
6458 };
6459 
6460 static int __ext4_remount(struct fs_context *fc, struct super_block *sb)
6461 {
6462 	struct ext4_fs_context *ctx = fc->fs_private;
6463 	struct ext4_super_block *es;
6464 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6465 	unsigned long old_sb_flags;
6466 	struct ext4_mount_options old_opts;
6467 	ext4_group_t g;
6468 	int err = 0;
6469 	int alloc_ctx;
6470 #ifdef CONFIG_QUOTA
6471 	int enable_quota = 0;
6472 	int i, j;
6473 	char *to_free[EXT4_MAXQUOTAS];
6474 #endif
6475 
6476 
6477 	/* Store the original options */
6478 	old_sb_flags = sb->s_flags;
6479 	old_opts.s_mount_opt = sbi->s_mount_opt;
6480 	old_opts.s_mount_opt2 = sbi->s_mount_opt2;
6481 	old_opts.s_resuid = sbi->s_resuid;
6482 	old_opts.s_resgid = sbi->s_resgid;
6483 	old_opts.s_commit_interval = sbi->s_commit_interval;
6484 	old_opts.s_min_batch_time = sbi->s_min_batch_time;
6485 	old_opts.s_max_batch_time = sbi->s_max_batch_time;
6486 #ifdef CONFIG_QUOTA
6487 	old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
6488 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6489 		if (sbi->s_qf_names[i]) {
6490 			char *qf_name = get_qf_name(sb, sbi, i);
6491 
6492 			old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
6493 			if (!old_opts.s_qf_names[i]) {
6494 				for (j = 0; j < i; j++)
6495 					kfree(old_opts.s_qf_names[j]);
6496 				return -ENOMEM;
6497 			}
6498 		} else
6499 			old_opts.s_qf_names[i] = NULL;
6500 #endif
6501 	if (!(ctx->spec & EXT4_SPEC_JOURNAL_IOPRIO)) {
6502 		if (sbi->s_journal && sbi->s_journal->j_task->io_context)
6503 			ctx->journal_ioprio =
6504 				sbi->s_journal->j_task->io_context->ioprio;
6505 		else
6506 			ctx->journal_ioprio = EXT4_DEF_JOURNAL_IOPRIO;
6507 
6508 	}
6509 
6510 	if ((ctx->spec & EXT4_SPEC_s_stripe) &&
6511 	    ext4_is_stripe_incompatible(sb, ctx->s_stripe)) {
6512 		ext4_msg(sb, KERN_WARNING,
6513 			 "stripe (%lu) is not aligned with cluster size (%u), "
6514 			 "stripe is disabled",
6515 			 ctx->s_stripe, sbi->s_cluster_ratio);
6516 		ctx->s_stripe = 0;
6517 	}
6518 
6519 	/*
6520 	 * Changing the DIOREAD_NOLOCK or DELALLOC mount options may cause
6521 	 * two calls to ext4_should_dioread_nolock() to return inconsistent
6522 	 * values, triggering WARN_ON in ext4_add_complete_io(). we grab
6523 	 * here s_writepages_rwsem to avoid race between writepages ops and
6524 	 * remount.
6525 	 */
6526 	alloc_ctx = ext4_writepages_down_write(sb);
6527 	ext4_apply_options(fc, sb);
6528 	ext4_writepages_up_write(sb, alloc_ctx);
6529 
6530 	if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
6531 	    test_opt(sb, JOURNAL_CHECKSUM)) {
6532 		ext4_msg(sb, KERN_ERR, "changing journal_checksum "
6533 			 "during remount not supported; ignoring");
6534 		sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
6535 	}
6536 
6537 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
6538 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
6539 			ext4_msg(sb, KERN_ERR, "can't mount with "
6540 				 "both data=journal and delalloc");
6541 			err = -EINVAL;
6542 			goto restore_opts;
6543 		}
6544 		if (test_opt(sb, DIOREAD_NOLOCK)) {
6545 			ext4_msg(sb, KERN_ERR, "can't mount with "
6546 				 "both data=journal and dioread_nolock");
6547 			err = -EINVAL;
6548 			goto restore_opts;
6549 		}
6550 	} else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
6551 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
6552 			ext4_msg(sb, KERN_ERR, "can't mount with "
6553 				"journal_async_commit in data=ordered mode");
6554 			err = -EINVAL;
6555 			goto restore_opts;
6556 		}
6557 	}
6558 
6559 	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
6560 		ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
6561 		err = -EINVAL;
6562 		goto restore_opts;
6563 	}
6564 
6565 	if ((old_opts.s_mount_opt & EXT4_MOUNT_DELALLOC) &&
6566 	    !test_opt(sb, DELALLOC)) {
6567 		ext4_msg(sb, KERN_ERR, "can't disable delalloc during remount");
6568 		err = -EINVAL;
6569 		goto restore_opts;
6570 	}
6571 
6572 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
6573 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
6574 
6575 	es = sbi->s_es;
6576 
6577 	if (sbi->s_journal) {
6578 		ext4_init_journal_params(sb, sbi->s_journal);
6579 		set_task_ioprio(sbi->s_journal->j_task, ctx->journal_ioprio);
6580 	}
6581 
6582 	/* Flush outstanding errors before changing fs state */
6583 	flush_work(&sbi->s_sb_upd_work);
6584 
6585 	if ((bool)(fc->sb_flags & SB_RDONLY) != sb_rdonly(sb)) {
6586 		if (ext4_emergency_state(sb)) {
6587 			err = -EROFS;
6588 			goto restore_opts;
6589 		}
6590 
6591 		if (fc->sb_flags & SB_RDONLY) {
6592 			err = sync_filesystem(sb);
6593 			if (err < 0)
6594 				goto restore_opts;
6595 			err = dquot_suspend(sb, -1);
6596 			if (err < 0)
6597 				goto restore_opts;
6598 
6599 			/*
6600 			 * First of all, the unconditional stuff we have to do
6601 			 * to disable replay of the journal when we next remount
6602 			 */
6603 			sb->s_flags |= SB_RDONLY;
6604 
6605 			/*
6606 			 * OK, test if we are remounting a valid rw partition
6607 			 * readonly, and if so set the rdonly flag and then
6608 			 * mark the partition as valid again.
6609 			 */
6610 			if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
6611 			    (sbi->s_mount_state & EXT4_VALID_FS))
6612 				es->s_state = cpu_to_le16(sbi->s_mount_state);
6613 
6614 			if (sbi->s_journal) {
6615 				/*
6616 				 * We let remount-ro finish even if marking fs
6617 				 * as clean failed...
6618 				 */
6619 				ext4_mark_recovery_complete(sb, es);
6620 			}
6621 		} else {
6622 			/* Make sure we can mount this feature set readwrite */
6623 			if (ext4_has_feature_readonly(sb) ||
6624 			    !ext4_feature_set_ok(sb, 0)) {
6625 				err = -EROFS;
6626 				goto restore_opts;
6627 			}
6628 			/*
6629 			 * Make sure the group descriptor checksums
6630 			 * are sane.  If they aren't, refuse to remount r/w.
6631 			 */
6632 			for (g = 0; g < sbi->s_groups_count; g++) {
6633 				struct ext4_group_desc *gdp =
6634 					ext4_get_group_desc(sb, g, NULL);
6635 
6636 				if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
6637 					ext4_msg(sb, KERN_ERR,
6638 	       "ext4_remount: Checksum for group %u failed (%u!=%u)",
6639 		g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
6640 					       le16_to_cpu(gdp->bg_checksum));
6641 					err = -EFSBADCRC;
6642 					goto restore_opts;
6643 				}
6644 			}
6645 
6646 			/*
6647 			 * If we have an unprocessed orphan list hanging
6648 			 * around from a previously readonly bdev mount,
6649 			 * require a full umount/remount for now.
6650 			 */
6651 			if (es->s_last_orphan || !ext4_orphan_file_empty(sb)) {
6652 				ext4_msg(sb, KERN_WARNING, "Couldn't "
6653 				       "remount RDWR because of unprocessed "
6654 				       "orphan inode list.  Please "
6655 				       "umount/remount instead");
6656 				err = -EINVAL;
6657 				goto restore_opts;
6658 			}
6659 
6660 			/*
6661 			 * Mounting a RDONLY partition read-write, so reread
6662 			 * and store the current valid flag.  (It may have
6663 			 * been changed by e2fsck since we originally mounted
6664 			 * the partition.)
6665 			 */
6666 			if (sbi->s_journal) {
6667 				err = ext4_clear_journal_err(sb, es);
6668 				if (err)
6669 					goto restore_opts;
6670 			}
6671 			sbi->s_mount_state = (le16_to_cpu(es->s_state) &
6672 					      ~EXT4_FC_REPLAY);
6673 
6674 			err = ext4_setup_super(sb, es, 0);
6675 			if (err)
6676 				goto restore_opts;
6677 
6678 			sb->s_flags &= ~SB_RDONLY;
6679 			if (ext4_has_feature_mmp(sb)) {
6680 				err = ext4_multi_mount_protect(sb,
6681 						le64_to_cpu(es->s_mmp_block));
6682 				if (err)
6683 					goto restore_opts;
6684 			}
6685 #ifdef CONFIG_QUOTA
6686 			enable_quota = 1;
6687 #endif
6688 		}
6689 	}
6690 
6691 	/*
6692 	 * Handle creation of system zone data early because it can fail.
6693 	 * Releasing of existing data is done when we are sure remount will
6694 	 * succeed.
6695 	 */
6696 	if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6697 		err = ext4_setup_system_zone(sb);
6698 		if (err)
6699 			goto restore_opts;
6700 	}
6701 
6702 	if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6703 		err = ext4_commit_super(sb);
6704 		if (err)
6705 			goto restore_opts;
6706 	}
6707 
6708 #ifdef CONFIG_QUOTA
6709 	if (enable_quota) {
6710 		if (sb_any_quota_suspended(sb))
6711 			dquot_resume(sb, -1);
6712 		else if (ext4_has_feature_quota(sb)) {
6713 			err = ext4_enable_quotas(sb);
6714 			if (err)
6715 				goto restore_opts;
6716 		}
6717 	}
6718 	/* Release old quota file names */
6719 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6720 		kfree(old_opts.s_qf_names[i]);
6721 #endif
6722 	if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6723 		ext4_release_system_zone(sb);
6724 
6725 	/*
6726 	 * Reinitialize lazy itable initialization thread based on
6727 	 * current settings
6728 	 */
6729 	if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
6730 		ext4_unregister_li_request(sb);
6731 	else {
6732 		ext4_group_t first_not_zeroed;
6733 		first_not_zeroed = ext4_has_uninit_itable(sb);
6734 		ext4_register_li_request(sb, first_not_zeroed);
6735 	}
6736 
6737 	if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6738 		ext4_stop_mmpd(sbi);
6739 
6740 	/*
6741 	 * Handle aborting the filesystem as the last thing during remount to
6742 	 * avoid obsure errors during remount when some option changes fail to
6743 	 * apply due to shutdown filesystem.
6744 	 */
6745 	if (test_opt2(sb, ABORT))
6746 		ext4_abort(sb, ESHUTDOWN, "Abort forced by user");
6747 
6748 	return 0;
6749 
6750 restore_opts:
6751 	/*
6752 	 * If there was a failing r/w to ro transition, we may need to
6753 	 * re-enable quota
6754 	 */
6755 	if (sb_rdonly(sb) && !(old_sb_flags & SB_RDONLY) &&
6756 	    sb_any_quota_suspended(sb))
6757 		dquot_resume(sb, -1);
6758 
6759 	alloc_ctx = ext4_writepages_down_write(sb);
6760 	sb->s_flags = old_sb_flags;
6761 	sbi->s_mount_opt = old_opts.s_mount_opt;
6762 	sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6763 	sbi->s_resuid = old_opts.s_resuid;
6764 	sbi->s_resgid = old_opts.s_resgid;
6765 	sbi->s_commit_interval = old_opts.s_commit_interval;
6766 	sbi->s_min_batch_time = old_opts.s_min_batch_time;
6767 	sbi->s_max_batch_time = old_opts.s_max_batch_time;
6768 	ext4_writepages_up_write(sb, alloc_ctx);
6769 
6770 	if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6771 		ext4_release_system_zone(sb);
6772 #ifdef CONFIG_QUOTA
6773 	sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6774 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6775 		to_free[i] = get_qf_name(sb, sbi, i);
6776 		rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6777 	}
6778 	synchronize_rcu();
6779 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
6780 		kfree(to_free[i]);
6781 #endif
6782 	if (!ext4_has_feature_mmp(sb) || sb_rdonly(sb))
6783 		ext4_stop_mmpd(sbi);
6784 	return err;
6785 }
6786 
6787 static int ext4_reconfigure(struct fs_context *fc)
6788 {
6789 	struct super_block *sb = fc->root->d_sb;
6790 	int ret;
6791 	bool old_ro = sb_rdonly(sb);
6792 
6793 	fc->s_fs_info = EXT4_SB(sb);
6794 
6795 	ret = ext4_check_opt_consistency(fc, sb);
6796 	if (ret < 0)
6797 		return ret;
6798 
6799 	ret = __ext4_remount(fc, sb);
6800 	if (ret < 0)
6801 		return ret;
6802 
6803 	ext4_msg(sb, KERN_INFO, "re-mounted %pU%s.",
6804 		 &sb->s_uuid,
6805 		 (old_ro != sb_rdonly(sb)) ? (sb_rdonly(sb) ? " ro" : " r/w") : "");
6806 
6807 	return 0;
6808 }
6809 
6810 #ifdef CONFIG_QUOTA
6811 static int ext4_statfs_project(struct super_block *sb,
6812 			       kprojid_t projid, struct kstatfs *buf)
6813 {
6814 	struct kqid qid;
6815 	struct dquot *dquot;
6816 	u64 limit;
6817 	u64 curblock;
6818 
6819 	qid = make_kqid_projid(projid);
6820 	dquot = dqget(sb, qid);
6821 	if (IS_ERR(dquot))
6822 		return PTR_ERR(dquot);
6823 	spin_lock(&dquot->dq_dqb_lock);
6824 
6825 	limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6826 			     dquot->dq_dqb.dqb_bhardlimit);
6827 	limit >>= sb->s_blocksize_bits;
6828 
6829 	if (limit) {
6830 		uint64_t	remaining = 0;
6831 
6832 		curblock = (dquot->dq_dqb.dqb_curspace +
6833 			    dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6834 		if (limit > curblock)
6835 			remaining = limit - curblock;
6836 
6837 		buf->f_blocks = min(buf->f_blocks, limit);
6838 		buf->f_bfree = min(buf->f_bfree, remaining);
6839 		buf->f_bavail = min(buf->f_bavail, remaining);
6840 	}
6841 
6842 	limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6843 			     dquot->dq_dqb.dqb_ihardlimit);
6844 	if (limit) {
6845 		uint64_t	remaining = 0;
6846 
6847 		if (limit > dquot->dq_dqb.dqb_curinodes)
6848 			remaining = limit - dquot->dq_dqb.dqb_curinodes;
6849 
6850 		buf->f_files = min(buf->f_files, limit);
6851 		buf->f_ffree = min(buf->f_ffree, remaining);
6852 	}
6853 
6854 	spin_unlock(&dquot->dq_dqb_lock);
6855 	dqput(dquot);
6856 	return 0;
6857 }
6858 #endif
6859 
6860 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6861 {
6862 	struct super_block *sb = dentry->d_sb;
6863 	struct ext4_sb_info *sbi = EXT4_SB(sb);
6864 	struct ext4_super_block *es = sbi->s_es;
6865 	ext4_fsblk_t overhead = 0, resv_blocks;
6866 	s64 bfree;
6867 	resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6868 
6869 	if (!test_opt(sb, MINIX_DF))
6870 		overhead = sbi->s_overhead;
6871 
6872 	buf->f_type = EXT4_SUPER_MAGIC;
6873 	buf->f_bsize = sb->s_blocksize;
6874 	buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6875 	bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6876 		percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6877 	/* prevent underflow in case that few free space is available */
6878 	buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6879 	buf->f_bavail = buf->f_bfree -
6880 			(ext4_r_blocks_count(es) + resv_blocks);
6881 	if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6882 		buf->f_bavail = 0;
6883 	buf->f_files = le32_to_cpu(es->s_inodes_count);
6884 	buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6885 	buf->f_namelen = EXT4_NAME_LEN;
6886 	buf->f_fsid = uuid_to_fsid(es->s_uuid);
6887 
6888 #ifdef CONFIG_QUOTA
6889 	if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6890 	    sb_has_quota_limits_enabled(sb, PRJQUOTA))
6891 		ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6892 #endif
6893 	return 0;
6894 }
6895 
6896 
6897 #ifdef CONFIG_QUOTA
6898 
6899 /*
6900  * Helper functions so that transaction is started before we acquire dqio_sem
6901  * to keep correct lock ordering of transaction > dqio_sem
6902  */
6903 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6904 {
6905 	return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6906 }
6907 
6908 static int ext4_write_dquot(struct dquot *dquot)
6909 {
6910 	int ret, err;
6911 	handle_t *handle;
6912 	struct inode *inode;
6913 
6914 	inode = dquot_to_inode(dquot);
6915 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6916 				    EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6917 	if (IS_ERR(handle))
6918 		return PTR_ERR(handle);
6919 	ret = dquot_commit(dquot);
6920 	if (ret < 0)
6921 		ext4_error_err(dquot->dq_sb, -ret,
6922 			       "Failed to commit dquot type %d",
6923 			       dquot->dq_id.type);
6924 	err = ext4_journal_stop(handle);
6925 	if (!ret)
6926 		ret = err;
6927 	return ret;
6928 }
6929 
6930 static int ext4_acquire_dquot(struct dquot *dquot)
6931 {
6932 	int ret, err;
6933 	handle_t *handle;
6934 
6935 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6936 				    EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6937 	if (IS_ERR(handle))
6938 		return PTR_ERR(handle);
6939 	ret = dquot_acquire(dquot);
6940 	if (ret < 0)
6941 		ext4_error_err(dquot->dq_sb, -ret,
6942 			      "Failed to acquire dquot type %d",
6943 			      dquot->dq_id.type);
6944 	err = ext4_journal_stop(handle);
6945 	if (!ret)
6946 		ret = err;
6947 	return ret;
6948 }
6949 
6950 static int ext4_release_dquot(struct dquot *dquot)
6951 {
6952 	int ret, err;
6953 	handle_t *handle;
6954 	bool freeze_protected = false;
6955 
6956 	/*
6957 	 * Trying to sb_start_intwrite() in a running transaction
6958 	 * can result in a deadlock. Further, running transactions
6959 	 * are already protected from freezing.
6960 	 */
6961 	if (!ext4_journal_current_handle()) {
6962 		sb_start_intwrite(dquot->dq_sb);
6963 		freeze_protected = true;
6964 	}
6965 
6966 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6967 				    EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6968 	if (IS_ERR(handle)) {
6969 		/* Release dquot anyway to avoid endless cycle in dqput() */
6970 		dquot_release(dquot);
6971 		if (freeze_protected)
6972 			sb_end_intwrite(dquot->dq_sb);
6973 		return PTR_ERR(handle);
6974 	}
6975 	ret = dquot_release(dquot);
6976 	if (ret < 0)
6977 		ext4_error_err(dquot->dq_sb, -ret,
6978 			       "Failed to release dquot type %d",
6979 			       dquot->dq_id.type);
6980 	err = ext4_journal_stop(handle);
6981 	if (!ret)
6982 		ret = err;
6983 
6984 	if (freeze_protected)
6985 		sb_end_intwrite(dquot->dq_sb);
6986 
6987 	return ret;
6988 }
6989 
6990 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6991 {
6992 	struct super_block *sb = dquot->dq_sb;
6993 
6994 	if (ext4_is_quota_journalled(sb)) {
6995 		dquot_mark_dquot_dirty(dquot);
6996 		return ext4_write_dquot(dquot);
6997 	} else {
6998 		return dquot_mark_dquot_dirty(dquot);
6999 	}
7000 }
7001 
7002 static int ext4_write_info(struct super_block *sb, int type)
7003 {
7004 	int ret, err;
7005 	handle_t *handle;
7006 
7007 	/* Data block + inode block */
7008 	handle = ext4_journal_start_sb(sb, EXT4_HT_QUOTA, 2);
7009 	if (IS_ERR(handle))
7010 		return PTR_ERR(handle);
7011 	ret = dquot_commit_info(sb, type);
7012 	err = ext4_journal_stop(handle);
7013 	if (!ret)
7014 		ret = err;
7015 	return ret;
7016 }
7017 
7018 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
7019 {
7020 	struct ext4_inode_info *ei = EXT4_I(inode);
7021 
7022 	/* The first argument of lockdep_set_subclass has to be
7023 	 * *exactly* the same as the argument to init_rwsem() --- in
7024 	 * this case, in init_once() --- or lockdep gets unhappy
7025 	 * because the name of the lock is set using the
7026 	 * stringification of the argument to init_rwsem().
7027 	 */
7028 	(void) ei;	/* shut up clang warning if !CONFIG_LOCKDEP */
7029 	lockdep_set_subclass(&ei->i_data_sem, subclass);
7030 }
7031 
7032 /*
7033  * Standard function to be called on quota_on
7034  */
7035 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
7036 			 const struct path *path)
7037 {
7038 	int err;
7039 
7040 	if (!test_opt(sb, QUOTA))
7041 		return -EINVAL;
7042 
7043 	/* Quotafile not on the same filesystem? */
7044 	if (path->dentry->d_sb != sb)
7045 		return -EXDEV;
7046 
7047 	/* Quota already enabled for this file? */
7048 	if (IS_NOQUOTA(d_inode(path->dentry)))
7049 		return -EBUSY;
7050 
7051 	/* Journaling quota? */
7052 	if (EXT4_SB(sb)->s_qf_names[type]) {
7053 		/* Quotafile not in fs root? */
7054 		if (path->dentry->d_parent != sb->s_root)
7055 			ext4_msg(sb, KERN_WARNING,
7056 				"Quota file not on filesystem root. "
7057 				"Journaled quota will not work");
7058 		sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
7059 	} else {
7060 		/*
7061 		 * Clear the flag just in case mount options changed since
7062 		 * last time.
7063 		 */
7064 		sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
7065 	}
7066 
7067 	lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
7068 	err = dquot_quota_on(sb, type, format_id, path);
7069 	if (!err) {
7070 		struct inode *inode = d_inode(path->dentry);
7071 		handle_t *handle;
7072 
7073 		/*
7074 		 * Set inode flags to prevent userspace from messing with quota
7075 		 * files. If this fails, we return success anyway since quotas
7076 		 * are already enabled and this is not a hard failure.
7077 		 */
7078 		inode_lock(inode);
7079 		handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7080 		if (IS_ERR(handle))
7081 			goto unlock_inode;
7082 		EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
7083 		inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
7084 				S_NOATIME | S_IMMUTABLE);
7085 		err = ext4_mark_inode_dirty(handle, inode);
7086 		ext4_journal_stop(handle);
7087 	unlock_inode:
7088 		inode_unlock(inode);
7089 		if (err)
7090 			dquot_quota_off(sb, type);
7091 	}
7092 	if (err)
7093 		lockdep_set_quota_inode(path->dentry->d_inode,
7094 					     I_DATA_SEM_NORMAL);
7095 	return err;
7096 }
7097 
7098 static inline bool ext4_check_quota_inum(int type, unsigned long qf_inum)
7099 {
7100 	switch (type) {
7101 	case USRQUOTA:
7102 		return qf_inum == EXT4_USR_QUOTA_INO;
7103 	case GRPQUOTA:
7104 		return qf_inum == EXT4_GRP_QUOTA_INO;
7105 	case PRJQUOTA:
7106 		return qf_inum >= EXT4_GOOD_OLD_FIRST_INO;
7107 	default:
7108 		BUG();
7109 	}
7110 }
7111 
7112 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
7113 			     unsigned int flags)
7114 {
7115 	int err;
7116 	struct inode *qf_inode;
7117 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7118 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7119 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7120 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7121 	};
7122 
7123 	BUG_ON(!ext4_has_feature_quota(sb));
7124 
7125 	if (!qf_inums[type])
7126 		return -EPERM;
7127 
7128 	if (!ext4_check_quota_inum(type, qf_inums[type])) {
7129 		ext4_error(sb, "Bad quota inum: %lu, type: %d",
7130 				qf_inums[type], type);
7131 		return -EUCLEAN;
7132 	}
7133 
7134 	qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
7135 	if (IS_ERR(qf_inode)) {
7136 		ext4_error(sb, "Bad quota inode: %lu, type: %d",
7137 				qf_inums[type], type);
7138 		return PTR_ERR(qf_inode);
7139 	}
7140 
7141 	/* Don't account quota for quota files to avoid recursion */
7142 	qf_inode->i_flags |= S_NOQUOTA;
7143 	lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
7144 	err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
7145 	if (err)
7146 		lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
7147 	iput(qf_inode);
7148 
7149 	return err;
7150 }
7151 
7152 /* Enable usage tracking for all quota types. */
7153 int ext4_enable_quotas(struct super_block *sb)
7154 {
7155 	int type, err = 0;
7156 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
7157 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
7158 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
7159 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
7160 	};
7161 	bool quota_mopt[EXT4_MAXQUOTAS] = {
7162 		test_opt(sb, USRQUOTA),
7163 		test_opt(sb, GRPQUOTA),
7164 		test_opt(sb, PRJQUOTA),
7165 	};
7166 
7167 	sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
7168 	for (type = 0; type < EXT4_MAXQUOTAS; type++) {
7169 		if (qf_inums[type]) {
7170 			err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
7171 				DQUOT_USAGE_ENABLED |
7172 				(quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
7173 			if (err) {
7174 				ext4_warning(sb,
7175 					"Failed to enable quota tracking "
7176 					"(type=%d, err=%d, ino=%lu). "
7177 					"Please run e2fsck to fix.", type,
7178 					err, qf_inums[type]);
7179 
7180 				ext4_quotas_off(sb, type);
7181 				return err;
7182 			}
7183 		}
7184 	}
7185 	return 0;
7186 }
7187 
7188 static int ext4_quota_off(struct super_block *sb, int type)
7189 {
7190 	struct inode *inode = sb_dqopt(sb)->files[type];
7191 	handle_t *handle;
7192 	int err;
7193 
7194 	/* Force all delayed allocation blocks to be allocated.
7195 	 * Caller already holds s_umount sem */
7196 	if (test_opt(sb, DELALLOC))
7197 		sync_filesystem(sb);
7198 
7199 	if (!inode || !igrab(inode))
7200 		goto out;
7201 
7202 	err = dquot_quota_off(sb, type);
7203 	if (err || ext4_has_feature_quota(sb))
7204 		goto out_put;
7205 	/*
7206 	 * When the filesystem was remounted read-only first, we cannot cleanup
7207 	 * inode flags here. Bad luck but people should be using QUOTA feature
7208 	 * these days anyway.
7209 	 */
7210 	if (sb_rdonly(sb))
7211 		goto out_put;
7212 
7213 	inode_lock(inode);
7214 	/*
7215 	 * Update modification times of quota files when userspace can
7216 	 * start looking at them. If we fail, we return success anyway since
7217 	 * this is not a hard failure and quotas are already disabled.
7218 	 */
7219 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
7220 	if (IS_ERR(handle)) {
7221 		err = PTR_ERR(handle);
7222 		goto out_unlock;
7223 	}
7224 	EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
7225 	inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
7226 	inode_set_mtime_to_ts(inode, inode_set_ctime_current(inode));
7227 	err = ext4_mark_inode_dirty(handle, inode);
7228 	ext4_journal_stop(handle);
7229 out_unlock:
7230 	inode_unlock(inode);
7231 out_put:
7232 	lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
7233 	iput(inode);
7234 	return err;
7235 out:
7236 	return dquot_quota_off(sb, type);
7237 }
7238 
7239 /* Read data from quotafile - avoid pagecache and such because we cannot afford
7240  * acquiring the locks... As quota files are never truncated and quota code
7241  * itself serializes the operations (and no one else should touch the files)
7242  * we don't have to be afraid of races */
7243 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
7244 			       size_t len, loff_t off)
7245 {
7246 	struct inode *inode = sb_dqopt(sb)->files[type];
7247 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7248 	int offset = off & (sb->s_blocksize - 1);
7249 	int tocopy;
7250 	size_t toread;
7251 	struct buffer_head *bh;
7252 	loff_t i_size = i_size_read(inode);
7253 
7254 	if (off > i_size)
7255 		return 0;
7256 	if (off+len > i_size)
7257 		len = i_size-off;
7258 	toread = len;
7259 	while (toread > 0) {
7260 		tocopy = min_t(unsigned long, sb->s_blocksize - offset, toread);
7261 		bh = ext4_bread(NULL, inode, blk, 0);
7262 		if (IS_ERR(bh))
7263 			return PTR_ERR(bh);
7264 		if (!bh)	/* A hole? */
7265 			memset(data, 0, tocopy);
7266 		else
7267 			memcpy(data, bh->b_data+offset, tocopy);
7268 		brelse(bh);
7269 		offset = 0;
7270 		toread -= tocopy;
7271 		data += tocopy;
7272 		blk++;
7273 	}
7274 	return len;
7275 }
7276 
7277 /* Write to quotafile (we know the transaction is already started and has
7278  * enough credits) */
7279 static ssize_t ext4_quota_write(struct super_block *sb, int type,
7280 				const char *data, size_t len, loff_t off)
7281 {
7282 	struct inode *inode = sb_dqopt(sb)->files[type];
7283 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
7284 	int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
7285 	int retries = 0;
7286 	struct buffer_head *bh;
7287 	handle_t *handle = journal_current_handle();
7288 
7289 	if (!handle) {
7290 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7291 			" cancelled because transaction is not started",
7292 			(unsigned long long)off, (unsigned long long)len);
7293 		return -EIO;
7294 	}
7295 	/*
7296 	 * Since we account only one data block in transaction credits,
7297 	 * then it is impossible to cross a block boundary.
7298 	 */
7299 	if (sb->s_blocksize - offset < len) {
7300 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
7301 			" cancelled because not block aligned",
7302 			(unsigned long long)off, (unsigned long long)len);
7303 		return -EIO;
7304 	}
7305 
7306 	do {
7307 		bh = ext4_bread(handle, inode, blk,
7308 				EXT4_GET_BLOCKS_CREATE |
7309 				EXT4_GET_BLOCKS_METADATA_NOFAIL);
7310 	} while (PTR_ERR(bh) == -ENOSPC &&
7311 		 ext4_should_retry_alloc(inode->i_sb, &retries));
7312 	if (IS_ERR(bh))
7313 		return PTR_ERR(bh);
7314 	if (!bh)
7315 		goto out;
7316 	BUFFER_TRACE(bh, "get write access");
7317 	err = ext4_journal_get_write_access(handle, sb, bh, EXT4_JTR_NONE);
7318 	if (err) {
7319 		brelse(bh);
7320 		return err;
7321 	}
7322 	lock_buffer(bh);
7323 	memcpy(bh->b_data+offset, data, len);
7324 	flush_dcache_folio(bh->b_folio);
7325 	unlock_buffer(bh);
7326 	err = ext4_handle_dirty_metadata(handle, NULL, bh);
7327 	brelse(bh);
7328 out:
7329 	if (inode->i_size < off + len) {
7330 		i_size_write(inode, off + len);
7331 		EXT4_I(inode)->i_disksize = inode->i_size;
7332 		err2 = ext4_mark_inode_dirty(handle, inode);
7333 		if (unlikely(err2 && !err))
7334 			err = err2;
7335 	}
7336 	return err ? err : len;
7337 }
7338 #endif
7339 
7340 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
7341 static inline void register_as_ext2(void)
7342 {
7343 	int err = register_filesystem(&ext2_fs_type);
7344 	if (err)
7345 		printk(KERN_WARNING
7346 		       "EXT4-fs: Unable to register as ext2 (%d)\n", err);
7347 }
7348 
7349 static inline void unregister_as_ext2(void)
7350 {
7351 	unregister_filesystem(&ext2_fs_type);
7352 }
7353 
7354 static inline int ext2_feature_set_ok(struct super_block *sb)
7355 {
7356 	if (ext4_has_unknown_ext2_incompat_features(sb))
7357 		return 0;
7358 	if (sb_rdonly(sb))
7359 		return 1;
7360 	if (ext4_has_unknown_ext2_ro_compat_features(sb))
7361 		return 0;
7362 	return 1;
7363 }
7364 #else
7365 static inline void register_as_ext2(void) { }
7366 static inline void unregister_as_ext2(void) { }
7367 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
7368 #endif
7369 
7370 static inline void register_as_ext3(void)
7371 {
7372 	int err = register_filesystem(&ext3_fs_type);
7373 	if (err)
7374 		printk(KERN_WARNING
7375 		       "EXT4-fs: Unable to register as ext3 (%d)\n", err);
7376 }
7377 
7378 static inline void unregister_as_ext3(void)
7379 {
7380 	unregister_filesystem(&ext3_fs_type);
7381 }
7382 
7383 static inline int ext3_feature_set_ok(struct super_block *sb)
7384 {
7385 	if (ext4_has_unknown_ext3_incompat_features(sb))
7386 		return 0;
7387 	if (!ext4_has_feature_journal(sb))
7388 		return 0;
7389 	if (sb_rdonly(sb))
7390 		return 1;
7391 	if (ext4_has_unknown_ext3_ro_compat_features(sb))
7392 		return 0;
7393 	return 1;
7394 }
7395 
7396 static void ext4_kill_sb(struct super_block *sb)
7397 {
7398 	struct ext4_sb_info *sbi = EXT4_SB(sb);
7399 	struct file *bdev_file = sbi ? sbi->s_journal_bdev_file : NULL;
7400 
7401 	kill_block_super(sb);
7402 
7403 	if (bdev_file)
7404 		bdev_fput(bdev_file);
7405 }
7406 
7407 static struct file_system_type ext4_fs_type = {
7408 	.owner			= THIS_MODULE,
7409 	.name			= "ext4",
7410 	.init_fs_context	= ext4_init_fs_context,
7411 	.parameters		= ext4_param_specs,
7412 	.kill_sb		= ext4_kill_sb,
7413 	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP | FS_MGTIME,
7414 };
7415 MODULE_ALIAS_FS("ext4");
7416 
7417 static int __init ext4_init_fs(void)
7418 {
7419 	int err;
7420 
7421 	ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
7422 	ext4_li_info = NULL;
7423 
7424 	/* Build-time check for flags consistency */
7425 	ext4_check_flag_values();
7426 
7427 	err = ext4_init_es();
7428 	if (err)
7429 		return err;
7430 
7431 	err = ext4_init_pending();
7432 	if (err)
7433 		goto out7;
7434 
7435 	err = ext4_init_post_read_processing();
7436 	if (err)
7437 		goto out6;
7438 
7439 	err = ext4_init_pageio();
7440 	if (err)
7441 		goto out5;
7442 
7443 	err = ext4_init_system_zone();
7444 	if (err)
7445 		goto out4;
7446 
7447 	err = ext4_init_sysfs();
7448 	if (err)
7449 		goto out3;
7450 
7451 	err = ext4_init_mballoc();
7452 	if (err)
7453 		goto out2;
7454 	err = init_inodecache();
7455 	if (err)
7456 		goto out1;
7457 
7458 	err = ext4_fc_init_dentry_cache();
7459 	if (err)
7460 		goto out05;
7461 
7462 	register_as_ext3();
7463 	register_as_ext2();
7464 	err = register_filesystem(&ext4_fs_type);
7465 	if (err)
7466 		goto out;
7467 
7468 	return 0;
7469 out:
7470 	unregister_as_ext2();
7471 	unregister_as_ext3();
7472 	ext4_fc_destroy_dentry_cache();
7473 out05:
7474 	destroy_inodecache();
7475 out1:
7476 	ext4_exit_mballoc();
7477 out2:
7478 	ext4_exit_sysfs();
7479 out3:
7480 	ext4_exit_system_zone();
7481 out4:
7482 	ext4_exit_pageio();
7483 out5:
7484 	ext4_exit_post_read_processing();
7485 out6:
7486 	ext4_exit_pending();
7487 out7:
7488 	ext4_exit_es();
7489 
7490 	return err;
7491 }
7492 
7493 static void __exit ext4_exit_fs(void)
7494 {
7495 	ext4_destroy_lazyinit_thread();
7496 	unregister_as_ext2();
7497 	unregister_as_ext3();
7498 	unregister_filesystem(&ext4_fs_type);
7499 	ext4_fc_destroy_dentry_cache();
7500 	destroy_inodecache();
7501 	ext4_exit_mballoc();
7502 	ext4_exit_sysfs();
7503 	ext4_exit_system_zone();
7504 	ext4_exit_pageio();
7505 	ext4_exit_post_read_processing();
7506 	ext4_exit_es();
7507 	ext4_exit_pending();
7508 }
7509 
7510 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
7511 MODULE_DESCRIPTION("Fourth Extended Filesystem");
7512 MODULE_LICENSE("GPL");
7513 module_init(ext4_init_fs)
7514 module_exit(ext4_exit_fs)
7515