xref: /openbmc/linux/fs/ext4/super.c (revision 15e3ae36)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/ext4/super.c
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/fs/minix/inode.c
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  *
16  *  Big-endian to little-endian byte-swapping/bitmaps by
17  *        David S. Miller (davem@caip.rutgers.edu), 1995
18  */
19 
20 #include <linux/module.h>
21 #include <linux/string.h>
22 #include <linux/fs.h>
23 #include <linux/time.h>
24 #include <linux/vmalloc.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/backing-dev.h>
29 #include <linux/parser.h>
30 #include <linux/buffer_head.h>
31 #include <linux/exportfs.h>
32 #include <linux/vfs.h>
33 #include <linux/random.h>
34 #include <linux/mount.h>
35 #include <linux/namei.h>
36 #include <linux/quotaops.h>
37 #include <linux/seq_file.h>
38 #include <linux/ctype.h>
39 #include <linux/log2.h>
40 #include <linux/crc16.h>
41 #include <linux/dax.h>
42 #include <linux/cleancache.h>
43 #include <linux/uaccess.h>
44 #include <linux/iversion.h>
45 #include <linux/unicode.h>
46 #include <linux/part_stat.h>
47 #include <linux/kthread.h>
48 #include <linux/freezer.h>
49 
50 #include "ext4.h"
51 #include "ext4_extents.h"	/* Needed for trace points definition */
52 #include "ext4_jbd2.h"
53 #include "xattr.h"
54 #include "acl.h"
55 #include "mballoc.h"
56 #include "fsmap.h"
57 
58 #define CREATE_TRACE_POINTS
59 #include <trace/events/ext4.h>
60 
61 static struct ext4_lazy_init *ext4_li_info;
62 static struct mutex ext4_li_mtx;
63 static struct ratelimit_state ext4_mount_msg_ratelimit;
64 
65 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
66 			     unsigned long journal_devnum);
67 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
68 static int ext4_commit_super(struct super_block *sb, int sync);
69 static void ext4_mark_recovery_complete(struct super_block *sb,
70 					struct ext4_super_block *es);
71 static void ext4_clear_journal_err(struct super_block *sb,
72 				   struct ext4_super_block *es);
73 static int ext4_sync_fs(struct super_block *sb, int wait);
74 static int ext4_remount(struct super_block *sb, int *flags, char *data);
75 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
76 static int ext4_unfreeze(struct super_block *sb);
77 static int ext4_freeze(struct super_block *sb);
78 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
79 		       const char *dev_name, void *data);
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 int ext4_feature_set_ok(struct super_block *sb, int readonly);
83 static void ext4_destroy_lazyinit_thread(void);
84 static void ext4_unregister_li_request(struct super_block *sb);
85 static void ext4_clear_request_list(void);
86 static struct inode *ext4_get_journal_inode(struct super_block *sb,
87 					    unsigned int journal_inum);
88 
89 /*
90  * Lock ordering
91  *
92  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
93  * i_mmap_rwsem (inode->i_mmap_rwsem)!
94  *
95  * page fault path:
96  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
97  *   page lock -> i_data_sem (rw)
98  *
99  * buffered write path:
100  * sb_start_write -> i_mutex -> mmap_sem
101  * sb_start_write -> i_mutex -> transaction start -> page lock ->
102  *   i_data_sem (rw)
103  *
104  * truncate:
105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
106  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
107  *   i_data_sem (rw)
108  *
109  * direct IO:
110  * sb_start_write -> i_mutex -> mmap_sem
111  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
112  *
113  * writepages:
114  * transaction start -> page lock(s) -> i_data_sem (rw)
115  */
116 
117 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
118 static struct file_system_type ext2_fs_type = {
119 	.owner		= THIS_MODULE,
120 	.name		= "ext2",
121 	.mount		= ext4_mount,
122 	.kill_sb	= kill_block_super,
123 	.fs_flags	= FS_REQUIRES_DEV,
124 };
125 MODULE_ALIAS_FS("ext2");
126 MODULE_ALIAS("ext2");
127 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
128 #else
129 #define IS_EXT2_SB(sb) (0)
130 #endif
131 
132 
133 static struct file_system_type ext3_fs_type = {
134 	.owner		= THIS_MODULE,
135 	.name		= "ext3",
136 	.mount		= ext4_mount,
137 	.kill_sb	= kill_block_super,
138 	.fs_flags	= FS_REQUIRES_DEV,
139 };
140 MODULE_ALIAS_FS("ext3");
141 MODULE_ALIAS("ext3");
142 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
143 
144 /*
145  * This works like sb_bread() except it uses ERR_PTR for error
146  * returns.  Currently with sb_bread it's impossible to distinguish
147  * between ENOMEM and EIO situations (since both result in a NULL
148  * return.
149  */
150 struct buffer_head *
151 ext4_sb_bread(struct super_block *sb, sector_t block, int op_flags)
152 {
153 	struct buffer_head *bh = sb_getblk(sb, block);
154 
155 	if (bh == NULL)
156 		return ERR_PTR(-ENOMEM);
157 	if (ext4_buffer_uptodate(bh))
158 		return bh;
159 	ll_rw_block(REQ_OP_READ, REQ_META | op_flags, 1, &bh);
160 	wait_on_buffer(bh);
161 	if (buffer_uptodate(bh))
162 		return bh;
163 	put_bh(bh);
164 	return ERR_PTR(-EIO);
165 }
166 
167 static int ext4_verify_csum_type(struct super_block *sb,
168 				 struct ext4_super_block *es)
169 {
170 	if (!ext4_has_feature_metadata_csum(sb))
171 		return 1;
172 
173 	return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
174 }
175 
176 static __le32 ext4_superblock_csum(struct super_block *sb,
177 				   struct ext4_super_block *es)
178 {
179 	struct ext4_sb_info *sbi = EXT4_SB(sb);
180 	int offset = offsetof(struct ext4_super_block, s_checksum);
181 	__u32 csum;
182 
183 	csum = ext4_chksum(sbi, ~0, (char *)es, offset);
184 
185 	return cpu_to_le32(csum);
186 }
187 
188 static int ext4_superblock_csum_verify(struct super_block *sb,
189 				       struct ext4_super_block *es)
190 {
191 	if (!ext4_has_metadata_csum(sb))
192 		return 1;
193 
194 	return es->s_checksum == ext4_superblock_csum(sb, es);
195 }
196 
197 void ext4_superblock_csum_set(struct super_block *sb)
198 {
199 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
200 
201 	if (!ext4_has_metadata_csum(sb))
202 		return;
203 
204 	es->s_checksum = ext4_superblock_csum(sb, es);
205 }
206 
207 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
208 			       struct ext4_group_desc *bg)
209 {
210 	return le32_to_cpu(bg->bg_block_bitmap_lo) |
211 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
212 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
213 }
214 
215 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
216 			       struct ext4_group_desc *bg)
217 {
218 	return le32_to_cpu(bg->bg_inode_bitmap_lo) |
219 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
220 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
221 }
222 
223 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
224 			      struct ext4_group_desc *bg)
225 {
226 	return le32_to_cpu(bg->bg_inode_table_lo) |
227 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
228 		 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
229 }
230 
231 __u32 ext4_free_group_clusters(struct super_block *sb,
232 			       struct ext4_group_desc *bg)
233 {
234 	return le16_to_cpu(bg->bg_free_blocks_count_lo) |
235 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
236 		 (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
237 }
238 
239 __u32 ext4_free_inodes_count(struct super_block *sb,
240 			      struct ext4_group_desc *bg)
241 {
242 	return le16_to_cpu(bg->bg_free_inodes_count_lo) |
243 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
244 		 (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
245 }
246 
247 __u32 ext4_used_dirs_count(struct super_block *sb,
248 			      struct ext4_group_desc *bg)
249 {
250 	return le16_to_cpu(bg->bg_used_dirs_count_lo) |
251 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
252 		 (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
253 }
254 
255 __u32 ext4_itable_unused_count(struct super_block *sb,
256 			      struct ext4_group_desc *bg)
257 {
258 	return le16_to_cpu(bg->bg_itable_unused_lo) |
259 		(EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
260 		 (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
261 }
262 
263 void ext4_block_bitmap_set(struct super_block *sb,
264 			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
265 {
266 	bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
267 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
268 		bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
269 }
270 
271 void ext4_inode_bitmap_set(struct super_block *sb,
272 			   struct ext4_group_desc *bg, ext4_fsblk_t blk)
273 {
274 	bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
275 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
276 		bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
277 }
278 
279 void ext4_inode_table_set(struct super_block *sb,
280 			  struct ext4_group_desc *bg, ext4_fsblk_t blk)
281 {
282 	bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
283 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
284 		bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
285 }
286 
287 void ext4_free_group_clusters_set(struct super_block *sb,
288 				  struct ext4_group_desc *bg, __u32 count)
289 {
290 	bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
291 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
292 		bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
293 }
294 
295 void ext4_free_inodes_set(struct super_block *sb,
296 			  struct ext4_group_desc *bg, __u32 count)
297 {
298 	bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
299 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
300 		bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
301 }
302 
303 void ext4_used_dirs_set(struct super_block *sb,
304 			  struct ext4_group_desc *bg, __u32 count)
305 {
306 	bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
307 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
308 		bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
309 }
310 
311 void ext4_itable_unused_set(struct super_block *sb,
312 			  struct ext4_group_desc *bg, __u32 count)
313 {
314 	bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
315 	if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
316 		bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
317 }
318 
319 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
320 {
321 	time64_t now = ktime_get_real_seconds();
322 
323 	now = clamp_val(now, 0, (1ull << 40) - 1);
324 
325 	*lo = cpu_to_le32(lower_32_bits(now));
326 	*hi = upper_32_bits(now);
327 }
328 
329 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
330 {
331 	return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
332 }
333 #define ext4_update_tstamp(es, tstamp) \
334 	__ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
335 #define ext4_get_tstamp(es, tstamp) \
336 	__ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
337 
338 static void __save_error_info(struct super_block *sb, int error,
339 			      __u32 ino, __u64 block,
340 			      const char *func, unsigned int line)
341 {
342 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
343 	int err;
344 
345 	EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
346 	if (bdev_read_only(sb->s_bdev))
347 		return;
348 	es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
349 	ext4_update_tstamp(es, s_last_error_time);
350 	strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
351 	es->s_last_error_line = cpu_to_le32(line);
352 	es->s_last_error_ino = cpu_to_le32(ino);
353 	es->s_last_error_block = cpu_to_le64(block);
354 	switch (error) {
355 	case EIO:
356 		err = EXT4_ERR_EIO;
357 		break;
358 	case ENOMEM:
359 		err = EXT4_ERR_ENOMEM;
360 		break;
361 	case EFSBADCRC:
362 		err = EXT4_ERR_EFSBADCRC;
363 		break;
364 	case 0:
365 	case EFSCORRUPTED:
366 		err = EXT4_ERR_EFSCORRUPTED;
367 		break;
368 	case ENOSPC:
369 		err = EXT4_ERR_ENOSPC;
370 		break;
371 	case ENOKEY:
372 		err = EXT4_ERR_ENOKEY;
373 		break;
374 	case EROFS:
375 		err = EXT4_ERR_EROFS;
376 		break;
377 	case EFBIG:
378 		err = EXT4_ERR_EFBIG;
379 		break;
380 	case EEXIST:
381 		err = EXT4_ERR_EEXIST;
382 		break;
383 	case ERANGE:
384 		err = EXT4_ERR_ERANGE;
385 		break;
386 	case EOVERFLOW:
387 		err = EXT4_ERR_EOVERFLOW;
388 		break;
389 	case EBUSY:
390 		err = EXT4_ERR_EBUSY;
391 		break;
392 	case ENOTDIR:
393 		err = EXT4_ERR_ENOTDIR;
394 		break;
395 	case ENOTEMPTY:
396 		err = EXT4_ERR_ENOTEMPTY;
397 		break;
398 	case ESHUTDOWN:
399 		err = EXT4_ERR_ESHUTDOWN;
400 		break;
401 	case EFAULT:
402 		err = EXT4_ERR_EFAULT;
403 		break;
404 	default:
405 		err = EXT4_ERR_UNKNOWN;
406 	}
407 	es->s_last_error_errcode = err;
408 	if (!es->s_first_error_time) {
409 		es->s_first_error_time = es->s_last_error_time;
410 		es->s_first_error_time_hi = es->s_last_error_time_hi;
411 		strncpy(es->s_first_error_func, func,
412 			sizeof(es->s_first_error_func));
413 		es->s_first_error_line = cpu_to_le32(line);
414 		es->s_first_error_ino = es->s_last_error_ino;
415 		es->s_first_error_block = es->s_last_error_block;
416 		es->s_first_error_errcode = es->s_last_error_errcode;
417 	}
418 	/*
419 	 * Start the daily error reporting function if it hasn't been
420 	 * started already
421 	 */
422 	if (!es->s_error_count)
423 		mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
424 	le32_add_cpu(&es->s_error_count, 1);
425 }
426 
427 static void save_error_info(struct super_block *sb, int error,
428 			    __u32 ino, __u64 block,
429 			    const char *func, unsigned int line)
430 {
431 	__save_error_info(sb, error, ino, block, func, line);
432 	if (!bdev_read_only(sb->s_bdev))
433 		ext4_commit_super(sb, 1);
434 }
435 
436 /*
437  * The del_gendisk() function uninitializes the disk-specific data
438  * structures, including the bdi structure, without telling anyone
439  * else.  Once this happens, any attempt to call mark_buffer_dirty()
440  * (for example, by ext4_commit_super), will cause a kernel OOPS.
441  * This is a kludge to prevent these oops until we can put in a proper
442  * hook in del_gendisk() to inform the VFS and file system layers.
443  */
444 static int block_device_ejected(struct super_block *sb)
445 {
446 	struct inode *bd_inode = sb->s_bdev->bd_inode;
447 	struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
448 
449 	return bdi->dev == NULL;
450 }
451 
452 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
453 {
454 	struct super_block		*sb = journal->j_private;
455 	struct ext4_sb_info		*sbi = EXT4_SB(sb);
456 	int				error = is_journal_aborted(journal);
457 	struct ext4_journal_cb_entry	*jce;
458 
459 	BUG_ON(txn->t_state == T_FINISHED);
460 
461 	ext4_process_freed_data(sb, txn->t_tid);
462 
463 	spin_lock(&sbi->s_md_lock);
464 	while (!list_empty(&txn->t_private_list)) {
465 		jce = list_entry(txn->t_private_list.next,
466 				 struct ext4_journal_cb_entry, jce_list);
467 		list_del_init(&jce->jce_list);
468 		spin_unlock(&sbi->s_md_lock);
469 		jce->jce_func(sb, jce, error);
470 		spin_lock(&sbi->s_md_lock);
471 	}
472 	spin_unlock(&sbi->s_md_lock);
473 }
474 
475 static bool system_going_down(void)
476 {
477 	return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
478 		|| system_state == SYSTEM_RESTART;
479 }
480 
481 /* Deal with the reporting of failure conditions on a filesystem such as
482  * inconsistencies detected or read IO failures.
483  *
484  * On ext2, we can store the error state of the filesystem in the
485  * superblock.  That is not possible on ext4, because we may have other
486  * write ordering constraints on the superblock which prevent us from
487  * writing it out straight away; and given that the journal is about to
488  * be aborted, we can't rely on the current, or future, transactions to
489  * write out the superblock safely.
490  *
491  * We'll just use the jbd2_journal_abort() error code to record an error in
492  * the journal instead.  On recovery, the journal will complain about
493  * that error until we've noted it down and cleared it.
494  */
495 
496 static void ext4_handle_error(struct super_block *sb)
497 {
498 	if (test_opt(sb, WARN_ON_ERROR))
499 		WARN_ON_ONCE(1);
500 
501 	if (sb_rdonly(sb))
502 		return;
503 
504 	if (!test_opt(sb, ERRORS_CONT)) {
505 		journal_t *journal = EXT4_SB(sb)->s_journal;
506 
507 		EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
508 		if (journal)
509 			jbd2_journal_abort(journal, -EIO);
510 	}
511 	/*
512 	 * We force ERRORS_RO behavior when system is rebooting. Otherwise we
513 	 * could panic during 'reboot -f' as the underlying device got already
514 	 * disabled.
515 	 */
516 	if (test_opt(sb, ERRORS_RO) || system_going_down()) {
517 		ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
518 		/*
519 		 * Make sure updated value of ->s_mount_flags will be visible
520 		 * before ->s_flags update
521 		 */
522 		smp_wmb();
523 		sb->s_flags |= SB_RDONLY;
524 	} else if (test_opt(sb, ERRORS_PANIC)) {
525 		if (EXT4_SB(sb)->s_journal &&
526 		  !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
527 			return;
528 		panic("EXT4-fs (device %s): panic forced after error\n",
529 			sb->s_id);
530 	}
531 }
532 
533 #define ext4_error_ratelimit(sb)					\
534 		___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),	\
535 			     "EXT4-fs error")
536 
537 void __ext4_error(struct super_block *sb, const char *function,
538 		  unsigned int line, int error, __u64 block,
539 		  const char *fmt, ...)
540 {
541 	struct va_format vaf;
542 	va_list args;
543 
544 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
545 		return;
546 
547 	trace_ext4_error(sb, function, line);
548 	if (ext4_error_ratelimit(sb)) {
549 		va_start(args, fmt);
550 		vaf.fmt = fmt;
551 		vaf.va = &args;
552 		printk(KERN_CRIT
553 		       "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
554 		       sb->s_id, function, line, current->comm, &vaf);
555 		va_end(args);
556 	}
557 	save_error_info(sb, error, 0, block, function, line);
558 	ext4_handle_error(sb);
559 }
560 
561 void __ext4_error_inode(struct inode *inode, const char *function,
562 			unsigned int line, ext4_fsblk_t block, int error,
563 			const char *fmt, ...)
564 {
565 	va_list args;
566 	struct va_format vaf;
567 
568 	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
569 		return;
570 
571 	trace_ext4_error(inode->i_sb, function, line);
572 	if (ext4_error_ratelimit(inode->i_sb)) {
573 		va_start(args, fmt);
574 		vaf.fmt = fmt;
575 		vaf.va = &args;
576 		if (block)
577 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
578 			       "inode #%lu: block %llu: comm %s: %pV\n",
579 			       inode->i_sb->s_id, function, line, inode->i_ino,
580 			       block, current->comm, &vaf);
581 		else
582 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
583 			       "inode #%lu: comm %s: %pV\n",
584 			       inode->i_sb->s_id, function, line, inode->i_ino,
585 			       current->comm, &vaf);
586 		va_end(args);
587 	}
588 	save_error_info(inode->i_sb, error, inode->i_ino, block,
589 			function, line);
590 	ext4_handle_error(inode->i_sb);
591 }
592 
593 void __ext4_error_file(struct file *file, const char *function,
594 		       unsigned int line, ext4_fsblk_t block,
595 		       const char *fmt, ...)
596 {
597 	va_list args;
598 	struct va_format vaf;
599 	struct ext4_super_block *es;
600 	struct inode *inode = file_inode(file);
601 	char pathname[80], *path;
602 
603 	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
604 		return;
605 
606 	trace_ext4_error(inode->i_sb, function, line);
607 	es = EXT4_SB(inode->i_sb)->s_es;
608 	if (ext4_error_ratelimit(inode->i_sb)) {
609 		path = file_path(file, pathname, sizeof(pathname));
610 		if (IS_ERR(path))
611 			path = "(unknown)";
612 		va_start(args, fmt);
613 		vaf.fmt = fmt;
614 		vaf.va = &args;
615 		if (block)
616 			printk(KERN_CRIT
617 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
618 			       "block %llu: comm %s: path %s: %pV\n",
619 			       inode->i_sb->s_id, function, line, inode->i_ino,
620 			       block, current->comm, path, &vaf);
621 		else
622 			printk(KERN_CRIT
623 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
624 			       "comm %s: path %s: %pV\n",
625 			       inode->i_sb->s_id, function, line, inode->i_ino,
626 			       current->comm, path, &vaf);
627 		va_end(args);
628 	}
629 	save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
630 			function, line);
631 	ext4_handle_error(inode->i_sb);
632 }
633 
634 const char *ext4_decode_error(struct super_block *sb, int errno,
635 			      char nbuf[16])
636 {
637 	char *errstr = NULL;
638 
639 	switch (errno) {
640 	case -EFSCORRUPTED:
641 		errstr = "Corrupt filesystem";
642 		break;
643 	case -EFSBADCRC:
644 		errstr = "Filesystem failed CRC";
645 		break;
646 	case -EIO:
647 		errstr = "IO failure";
648 		break;
649 	case -ENOMEM:
650 		errstr = "Out of memory";
651 		break;
652 	case -EROFS:
653 		if (!sb || (EXT4_SB(sb)->s_journal &&
654 			    EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
655 			errstr = "Journal has aborted";
656 		else
657 			errstr = "Readonly filesystem";
658 		break;
659 	default:
660 		/* If the caller passed in an extra buffer for unknown
661 		 * errors, textualise them now.  Else we just return
662 		 * NULL. */
663 		if (nbuf) {
664 			/* Check for truncated error codes... */
665 			if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
666 				errstr = nbuf;
667 		}
668 		break;
669 	}
670 
671 	return errstr;
672 }
673 
674 /* __ext4_std_error decodes expected errors from journaling functions
675  * automatically and invokes the appropriate error response.  */
676 
677 void __ext4_std_error(struct super_block *sb, const char *function,
678 		      unsigned int line, int errno)
679 {
680 	char nbuf[16];
681 	const char *errstr;
682 
683 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
684 		return;
685 
686 	/* Special case: if the error is EROFS, and we're not already
687 	 * inside a transaction, then there's really no point in logging
688 	 * an error. */
689 	if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
690 		return;
691 
692 	if (ext4_error_ratelimit(sb)) {
693 		errstr = ext4_decode_error(sb, errno, nbuf);
694 		printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
695 		       sb->s_id, function, line, errstr);
696 	}
697 
698 	save_error_info(sb, -errno, 0, 0, function, line);
699 	ext4_handle_error(sb);
700 }
701 
702 /*
703  * ext4_abort is a much stronger failure handler than ext4_error.  The
704  * abort function may be used to deal with unrecoverable failures such
705  * as journal IO errors or ENOMEM at a critical moment in log management.
706  *
707  * We unconditionally force the filesystem into an ABORT|READONLY state,
708  * unless the error response on the fs has been set to panic in which
709  * case we take the easy way out and panic immediately.
710  */
711 
712 void __ext4_abort(struct super_block *sb, const char *function,
713 		  unsigned int line, int error, const char *fmt, ...)
714 {
715 	struct va_format vaf;
716 	va_list args;
717 
718 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
719 		return;
720 
721 	save_error_info(sb, error, 0, 0, function, line);
722 	va_start(args, fmt);
723 	vaf.fmt = fmt;
724 	vaf.va = &args;
725 	printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
726 	       sb->s_id, function, line, &vaf);
727 	va_end(args);
728 
729 	if (sb_rdonly(sb) == 0) {
730 		ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
731 		EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
732 		/*
733 		 * Make sure updated value of ->s_mount_flags will be visible
734 		 * before ->s_flags update
735 		 */
736 		smp_wmb();
737 		sb->s_flags |= SB_RDONLY;
738 		if (EXT4_SB(sb)->s_journal)
739 			jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
740 	}
741 	if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
742 		if (EXT4_SB(sb)->s_journal &&
743 		  !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
744 			return;
745 		panic("EXT4-fs panic from previous error\n");
746 	}
747 }
748 
749 void __ext4_msg(struct super_block *sb,
750 		const char *prefix, const char *fmt, ...)
751 {
752 	struct va_format vaf;
753 	va_list args;
754 
755 	if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
756 		return;
757 
758 	va_start(args, fmt);
759 	vaf.fmt = fmt;
760 	vaf.va = &args;
761 	printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
762 	va_end(args);
763 }
764 
765 #define ext4_warning_ratelimit(sb)					\
766 		___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),	\
767 			     "EXT4-fs warning")
768 
769 void __ext4_warning(struct super_block *sb, const char *function,
770 		    unsigned int line, const char *fmt, ...)
771 {
772 	struct va_format vaf;
773 	va_list args;
774 
775 	if (!ext4_warning_ratelimit(sb))
776 		return;
777 
778 	va_start(args, fmt);
779 	vaf.fmt = fmt;
780 	vaf.va = &args;
781 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
782 	       sb->s_id, function, line, &vaf);
783 	va_end(args);
784 }
785 
786 void __ext4_warning_inode(const struct inode *inode, const char *function,
787 			  unsigned int line, const char *fmt, ...)
788 {
789 	struct va_format vaf;
790 	va_list args;
791 
792 	if (!ext4_warning_ratelimit(inode->i_sb))
793 		return;
794 
795 	va_start(args, fmt);
796 	vaf.fmt = fmt;
797 	vaf.va = &args;
798 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
799 	       "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
800 	       function, line, inode->i_ino, current->comm, &vaf);
801 	va_end(args);
802 }
803 
804 void __ext4_grp_locked_error(const char *function, unsigned int line,
805 			     struct super_block *sb, ext4_group_t grp,
806 			     unsigned long ino, ext4_fsblk_t block,
807 			     const char *fmt, ...)
808 __releases(bitlock)
809 __acquires(bitlock)
810 {
811 	struct va_format vaf;
812 	va_list args;
813 
814 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
815 		return;
816 
817 	trace_ext4_error(sb, function, line);
818 	__save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
819 
820 	if (ext4_error_ratelimit(sb)) {
821 		va_start(args, fmt);
822 		vaf.fmt = fmt;
823 		vaf.va = &args;
824 		printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
825 		       sb->s_id, function, line, grp);
826 		if (ino)
827 			printk(KERN_CONT "inode %lu: ", ino);
828 		if (block)
829 			printk(KERN_CONT "block %llu:",
830 			       (unsigned long long) block);
831 		printk(KERN_CONT "%pV\n", &vaf);
832 		va_end(args);
833 	}
834 
835 	if (test_opt(sb, WARN_ON_ERROR))
836 		WARN_ON_ONCE(1);
837 
838 	if (test_opt(sb, ERRORS_CONT)) {
839 		ext4_commit_super(sb, 0);
840 		return;
841 	}
842 
843 	ext4_unlock_group(sb, grp);
844 	ext4_commit_super(sb, 1);
845 	ext4_handle_error(sb);
846 	/*
847 	 * We only get here in the ERRORS_RO case; relocking the group
848 	 * may be dangerous, but nothing bad will happen since the
849 	 * filesystem will have already been marked read/only and the
850 	 * journal has been aborted.  We return 1 as a hint to callers
851 	 * who might what to use the return value from
852 	 * ext4_grp_locked_error() to distinguish between the
853 	 * ERRORS_CONT and ERRORS_RO case, and perhaps return more
854 	 * aggressively from the ext4 function in question, with a
855 	 * more appropriate error code.
856 	 */
857 	ext4_lock_group(sb, grp);
858 	return;
859 }
860 
861 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
862 				     ext4_group_t group,
863 				     unsigned int flags)
864 {
865 	struct ext4_sb_info *sbi = EXT4_SB(sb);
866 	struct ext4_group_info *grp = ext4_get_group_info(sb, group);
867 	struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
868 	int ret;
869 
870 	if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
871 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
872 					    &grp->bb_state);
873 		if (!ret)
874 			percpu_counter_sub(&sbi->s_freeclusters_counter,
875 					   grp->bb_free);
876 	}
877 
878 	if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
879 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
880 					    &grp->bb_state);
881 		if (!ret && gdp) {
882 			int count;
883 
884 			count = ext4_free_inodes_count(sb, gdp);
885 			percpu_counter_sub(&sbi->s_freeinodes_counter,
886 					   count);
887 		}
888 	}
889 }
890 
891 void ext4_update_dynamic_rev(struct super_block *sb)
892 {
893 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
894 
895 	if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
896 		return;
897 
898 	ext4_warning(sb,
899 		     "updating to rev %d because of new feature flag, "
900 		     "running e2fsck is recommended",
901 		     EXT4_DYNAMIC_REV);
902 
903 	es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
904 	es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
905 	es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
906 	/* leave es->s_feature_*compat flags alone */
907 	/* es->s_uuid will be set by e2fsck if empty */
908 
909 	/*
910 	 * The rest of the superblock fields should be zero, and if not it
911 	 * means they are likely already in use, so leave them alone.  We
912 	 * can leave it up to e2fsck to clean up any inconsistencies there.
913 	 */
914 }
915 
916 /*
917  * Open the external journal device
918  */
919 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
920 {
921 	struct block_device *bdev;
922 
923 	bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
924 	if (IS_ERR(bdev))
925 		goto fail;
926 	return bdev;
927 
928 fail:
929 	ext4_msg(sb, KERN_ERR,
930 		 "failed to open journal device unknown-block(%u,%u) %ld",
931 		 MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
932 	return NULL;
933 }
934 
935 /*
936  * Release the journal device
937  */
938 static void ext4_blkdev_put(struct block_device *bdev)
939 {
940 	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
941 }
942 
943 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
944 {
945 	struct block_device *bdev;
946 	bdev = sbi->journal_bdev;
947 	if (bdev) {
948 		ext4_blkdev_put(bdev);
949 		sbi->journal_bdev = NULL;
950 	}
951 }
952 
953 static inline struct inode *orphan_list_entry(struct list_head *l)
954 {
955 	return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
956 }
957 
958 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
959 {
960 	struct list_head *l;
961 
962 	ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
963 		 le32_to_cpu(sbi->s_es->s_last_orphan));
964 
965 	printk(KERN_ERR "sb_info orphan list:\n");
966 	list_for_each(l, &sbi->s_orphan) {
967 		struct inode *inode = orphan_list_entry(l);
968 		printk(KERN_ERR "  "
969 		       "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
970 		       inode->i_sb->s_id, inode->i_ino, inode,
971 		       inode->i_mode, inode->i_nlink,
972 		       NEXT_ORPHAN(inode));
973 	}
974 }
975 
976 #ifdef CONFIG_QUOTA
977 static int ext4_quota_off(struct super_block *sb, int type);
978 
979 static inline void ext4_quota_off_umount(struct super_block *sb)
980 {
981 	int type;
982 
983 	/* Use our quota_off function to clear inode flags etc. */
984 	for (type = 0; type < EXT4_MAXQUOTAS; type++)
985 		ext4_quota_off(sb, type);
986 }
987 
988 /*
989  * This is a helper function which is used in the mount/remount
990  * codepaths (which holds s_umount) to fetch the quota file name.
991  */
992 static inline char *get_qf_name(struct super_block *sb,
993 				struct ext4_sb_info *sbi,
994 				int type)
995 {
996 	return rcu_dereference_protected(sbi->s_qf_names[type],
997 					 lockdep_is_held(&sb->s_umount));
998 }
999 #else
1000 static inline void ext4_quota_off_umount(struct super_block *sb)
1001 {
1002 }
1003 #endif
1004 
1005 static void ext4_put_super(struct super_block *sb)
1006 {
1007 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1008 	struct ext4_super_block *es = sbi->s_es;
1009 	struct buffer_head **group_desc;
1010 	struct flex_groups **flex_groups;
1011 	int aborted = 0;
1012 	int i, err;
1013 
1014 	ext4_unregister_li_request(sb);
1015 	ext4_quota_off_umount(sb);
1016 
1017 	destroy_workqueue(sbi->rsv_conversion_wq);
1018 
1019 	/*
1020 	 * Unregister sysfs before destroying jbd2 journal.
1021 	 * Since we could still access attr_journal_task attribute via sysfs
1022 	 * path which could have sbi->s_journal->j_task as NULL
1023 	 */
1024 	ext4_unregister_sysfs(sb);
1025 
1026 	if (sbi->s_journal) {
1027 		aborted = is_journal_aborted(sbi->s_journal);
1028 		err = jbd2_journal_destroy(sbi->s_journal);
1029 		sbi->s_journal = NULL;
1030 		if ((err < 0) && !aborted) {
1031 			ext4_abort(sb, -err, "Couldn't clean up the journal");
1032 		}
1033 	}
1034 
1035 	ext4_es_unregister_shrinker(sbi);
1036 	del_timer_sync(&sbi->s_err_report);
1037 	ext4_release_system_zone(sb);
1038 	ext4_mb_release(sb);
1039 	ext4_ext_release(sb);
1040 
1041 	if (!sb_rdonly(sb) && !aborted) {
1042 		ext4_clear_feature_journal_needs_recovery(sb);
1043 		es->s_state = cpu_to_le16(sbi->s_mount_state);
1044 	}
1045 	if (!sb_rdonly(sb))
1046 		ext4_commit_super(sb, 1);
1047 
1048 	rcu_read_lock();
1049 	group_desc = rcu_dereference(sbi->s_group_desc);
1050 	for (i = 0; i < sbi->s_gdb_count; i++)
1051 		brelse(group_desc[i]);
1052 	kvfree(group_desc);
1053 	flex_groups = rcu_dereference(sbi->s_flex_groups);
1054 	if (flex_groups) {
1055 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1056 			kvfree(flex_groups[i]);
1057 		kvfree(flex_groups);
1058 	}
1059 	rcu_read_unlock();
1060 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
1061 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
1062 	percpu_counter_destroy(&sbi->s_dirs_counter);
1063 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1064 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
1065 #ifdef CONFIG_QUOTA
1066 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
1067 		kfree(get_qf_name(sb, sbi, i));
1068 #endif
1069 
1070 	/* Debugging code just in case the in-memory inode orphan list
1071 	 * isn't empty.  The on-disk one can be non-empty if we've
1072 	 * detected an error and taken the fs readonly, but the
1073 	 * in-memory list had better be clean by this point. */
1074 	if (!list_empty(&sbi->s_orphan))
1075 		dump_orphan_list(sb, sbi);
1076 	J_ASSERT(list_empty(&sbi->s_orphan));
1077 
1078 	sync_blockdev(sb->s_bdev);
1079 	invalidate_bdev(sb->s_bdev);
1080 	if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1081 		/*
1082 		 * Invalidate the journal device's buffers.  We don't want them
1083 		 * floating about in memory - the physical journal device may
1084 		 * hotswapped, and it breaks the `ro-after' testing code.
1085 		 */
1086 		sync_blockdev(sbi->journal_bdev);
1087 		invalidate_bdev(sbi->journal_bdev);
1088 		ext4_blkdev_remove(sbi);
1089 	}
1090 
1091 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1092 	sbi->s_ea_inode_cache = NULL;
1093 
1094 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1095 	sbi->s_ea_block_cache = NULL;
1096 
1097 	if (sbi->s_mmp_tsk)
1098 		kthread_stop(sbi->s_mmp_tsk);
1099 	brelse(sbi->s_sbh);
1100 	sb->s_fs_info = NULL;
1101 	/*
1102 	 * Now that we are completely done shutting down the
1103 	 * superblock, we need to actually destroy the kobject.
1104 	 */
1105 	kobject_put(&sbi->s_kobj);
1106 	wait_for_completion(&sbi->s_kobj_unregister);
1107 	if (sbi->s_chksum_driver)
1108 		crypto_free_shash(sbi->s_chksum_driver);
1109 	kfree(sbi->s_blockgroup_lock);
1110 	fs_put_dax(sbi->s_daxdev);
1111 #ifdef CONFIG_UNICODE
1112 	utf8_unload(sbi->s_encoding);
1113 #endif
1114 	kfree(sbi);
1115 }
1116 
1117 static struct kmem_cache *ext4_inode_cachep;
1118 
1119 /*
1120  * Called inside transaction, so use GFP_NOFS
1121  */
1122 static struct inode *ext4_alloc_inode(struct super_block *sb)
1123 {
1124 	struct ext4_inode_info *ei;
1125 
1126 	ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1127 	if (!ei)
1128 		return NULL;
1129 
1130 	inode_set_iversion(&ei->vfs_inode, 1);
1131 	spin_lock_init(&ei->i_raw_lock);
1132 	INIT_LIST_HEAD(&ei->i_prealloc_list);
1133 	spin_lock_init(&ei->i_prealloc_lock);
1134 	ext4_es_init_tree(&ei->i_es_tree);
1135 	rwlock_init(&ei->i_es_lock);
1136 	INIT_LIST_HEAD(&ei->i_es_list);
1137 	ei->i_es_all_nr = 0;
1138 	ei->i_es_shk_nr = 0;
1139 	ei->i_es_shrink_lblk = 0;
1140 	ei->i_reserved_data_blocks = 0;
1141 	spin_lock_init(&(ei->i_block_reservation_lock));
1142 	ext4_init_pending_tree(&ei->i_pending_tree);
1143 #ifdef CONFIG_QUOTA
1144 	ei->i_reserved_quota = 0;
1145 	memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1146 #endif
1147 	ei->jinode = NULL;
1148 	INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1149 	spin_lock_init(&ei->i_completed_io_lock);
1150 	ei->i_sync_tid = 0;
1151 	ei->i_datasync_tid = 0;
1152 	atomic_set(&ei->i_unwritten, 0);
1153 	INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1154 	return &ei->vfs_inode;
1155 }
1156 
1157 static int ext4_drop_inode(struct inode *inode)
1158 {
1159 	int drop = generic_drop_inode(inode);
1160 
1161 	if (!drop)
1162 		drop = fscrypt_drop_inode(inode);
1163 
1164 	trace_ext4_drop_inode(inode, drop);
1165 	return drop;
1166 }
1167 
1168 static void ext4_free_in_core_inode(struct inode *inode)
1169 {
1170 	fscrypt_free_inode(inode);
1171 	kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1172 }
1173 
1174 static void ext4_destroy_inode(struct inode *inode)
1175 {
1176 	if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1177 		ext4_msg(inode->i_sb, KERN_ERR,
1178 			 "Inode %lu (%p): orphan list check failed!",
1179 			 inode->i_ino, EXT4_I(inode));
1180 		print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1181 				EXT4_I(inode), sizeof(struct ext4_inode_info),
1182 				true);
1183 		dump_stack();
1184 	}
1185 }
1186 
1187 static void init_once(void *foo)
1188 {
1189 	struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1190 
1191 	INIT_LIST_HEAD(&ei->i_orphan);
1192 	init_rwsem(&ei->xattr_sem);
1193 	init_rwsem(&ei->i_data_sem);
1194 	init_rwsem(&ei->i_mmap_sem);
1195 	inode_init_once(&ei->vfs_inode);
1196 }
1197 
1198 static int __init init_inodecache(void)
1199 {
1200 	ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1201 				sizeof(struct ext4_inode_info), 0,
1202 				(SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1203 					SLAB_ACCOUNT),
1204 				offsetof(struct ext4_inode_info, i_data),
1205 				sizeof_field(struct ext4_inode_info, i_data),
1206 				init_once);
1207 	if (ext4_inode_cachep == NULL)
1208 		return -ENOMEM;
1209 	return 0;
1210 }
1211 
1212 static void destroy_inodecache(void)
1213 {
1214 	/*
1215 	 * Make sure all delayed rcu free inodes are flushed before we
1216 	 * destroy cache.
1217 	 */
1218 	rcu_barrier();
1219 	kmem_cache_destroy(ext4_inode_cachep);
1220 }
1221 
1222 void ext4_clear_inode(struct inode *inode)
1223 {
1224 	invalidate_inode_buffers(inode);
1225 	clear_inode(inode);
1226 	ext4_discard_preallocations(inode);
1227 	ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1228 	dquot_drop(inode);
1229 	if (EXT4_I(inode)->jinode) {
1230 		jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1231 					       EXT4_I(inode)->jinode);
1232 		jbd2_free_inode(EXT4_I(inode)->jinode);
1233 		EXT4_I(inode)->jinode = NULL;
1234 	}
1235 	fscrypt_put_encryption_info(inode);
1236 	fsverity_cleanup_inode(inode);
1237 }
1238 
1239 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1240 					u64 ino, u32 generation)
1241 {
1242 	struct inode *inode;
1243 
1244 	/*
1245 	 * Currently we don't know the generation for parent directory, so
1246 	 * a generation of 0 means "accept any"
1247 	 */
1248 	inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1249 	if (IS_ERR(inode))
1250 		return ERR_CAST(inode);
1251 	if (generation && inode->i_generation != generation) {
1252 		iput(inode);
1253 		return ERR_PTR(-ESTALE);
1254 	}
1255 
1256 	return inode;
1257 }
1258 
1259 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1260 					int fh_len, int fh_type)
1261 {
1262 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1263 				    ext4_nfs_get_inode);
1264 }
1265 
1266 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1267 					int fh_len, int fh_type)
1268 {
1269 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1270 				    ext4_nfs_get_inode);
1271 }
1272 
1273 static int ext4_nfs_commit_metadata(struct inode *inode)
1274 {
1275 	struct writeback_control wbc = {
1276 		.sync_mode = WB_SYNC_ALL
1277 	};
1278 
1279 	trace_ext4_nfs_commit_metadata(inode);
1280 	return ext4_write_inode(inode, &wbc);
1281 }
1282 
1283 /*
1284  * Try to release metadata pages (indirect blocks, directories) which are
1285  * mapped via the block device.  Since these pages could have journal heads
1286  * which would prevent try_to_free_buffers() from freeing them, we must use
1287  * jbd2 layer's try_to_free_buffers() function to release them.
1288  */
1289 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1290 				 gfp_t wait)
1291 {
1292 	journal_t *journal = EXT4_SB(sb)->s_journal;
1293 
1294 	WARN_ON(PageChecked(page));
1295 	if (!page_has_buffers(page))
1296 		return 0;
1297 	if (journal)
1298 		return jbd2_journal_try_to_free_buffers(journal, page,
1299 						wait & ~__GFP_DIRECT_RECLAIM);
1300 	return try_to_free_buffers(page);
1301 }
1302 
1303 #ifdef CONFIG_FS_ENCRYPTION
1304 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1305 {
1306 	return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1307 				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1308 }
1309 
1310 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1311 							void *fs_data)
1312 {
1313 	handle_t *handle = fs_data;
1314 	int res, res2, credits, retries = 0;
1315 
1316 	/*
1317 	 * Encrypting the root directory is not allowed because e2fsck expects
1318 	 * lost+found to exist and be unencrypted, and encrypting the root
1319 	 * directory would imply encrypting the lost+found directory as well as
1320 	 * the filename "lost+found" itself.
1321 	 */
1322 	if (inode->i_ino == EXT4_ROOT_INO)
1323 		return -EPERM;
1324 
1325 	if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1326 		return -EINVAL;
1327 
1328 	res = ext4_convert_inline_data(inode);
1329 	if (res)
1330 		return res;
1331 
1332 	/*
1333 	 * If a journal handle was specified, then the encryption context is
1334 	 * being set on a new inode via inheritance and is part of a larger
1335 	 * transaction to create the inode.  Otherwise the encryption context is
1336 	 * being set on an existing inode in its own transaction.  Only in the
1337 	 * latter case should the "retry on ENOSPC" logic be used.
1338 	 */
1339 
1340 	if (handle) {
1341 		res = ext4_xattr_set_handle(handle, inode,
1342 					    EXT4_XATTR_INDEX_ENCRYPTION,
1343 					    EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1344 					    ctx, len, 0);
1345 		if (!res) {
1346 			ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1347 			ext4_clear_inode_state(inode,
1348 					EXT4_STATE_MAY_INLINE_DATA);
1349 			/*
1350 			 * Update inode->i_flags - S_ENCRYPTED will be enabled,
1351 			 * S_DAX may be disabled
1352 			 */
1353 			ext4_set_inode_flags(inode);
1354 		}
1355 		return res;
1356 	}
1357 
1358 	res = dquot_initialize(inode);
1359 	if (res)
1360 		return res;
1361 retry:
1362 	res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1363 				     &credits);
1364 	if (res)
1365 		return res;
1366 
1367 	handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1368 	if (IS_ERR(handle))
1369 		return PTR_ERR(handle);
1370 
1371 	res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1372 				    EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1373 				    ctx, len, 0);
1374 	if (!res) {
1375 		ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1376 		/*
1377 		 * Update inode->i_flags - S_ENCRYPTED will be enabled,
1378 		 * S_DAX may be disabled
1379 		 */
1380 		ext4_set_inode_flags(inode);
1381 		res = ext4_mark_inode_dirty(handle, inode);
1382 		if (res)
1383 			EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1384 	}
1385 	res2 = ext4_journal_stop(handle);
1386 
1387 	if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1388 		goto retry;
1389 	if (!res)
1390 		res = res2;
1391 	return res;
1392 }
1393 
1394 static bool ext4_dummy_context(struct inode *inode)
1395 {
1396 	return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1397 }
1398 
1399 static bool ext4_has_stable_inodes(struct super_block *sb)
1400 {
1401 	return ext4_has_feature_stable_inodes(sb);
1402 }
1403 
1404 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1405 				       int *ino_bits_ret, int *lblk_bits_ret)
1406 {
1407 	*ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1408 	*lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1409 }
1410 
1411 static const struct fscrypt_operations ext4_cryptops = {
1412 	.key_prefix		= "ext4:",
1413 	.get_context		= ext4_get_context,
1414 	.set_context		= ext4_set_context,
1415 	.dummy_context		= ext4_dummy_context,
1416 	.empty_dir		= ext4_empty_dir,
1417 	.max_namelen		= EXT4_NAME_LEN,
1418 	.has_stable_inodes	= ext4_has_stable_inodes,
1419 	.get_ino_and_lblk_bits	= ext4_get_ino_and_lblk_bits,
1420 };
1421 #endif
1422 
1423 #ifdef CONFIG_QUOTA
1424 static const char * const quotatypes[] = INITQFNAMES;
1425 #define QTYPE2NAME(t) (quotatypes[t])
1426 
1427 static int ext4_write_dquot(struct dquot *dquot);
1428 static int ext4_acquire_dquot(struct dquot *dquot);
1429 static int ext4_release_dquot(struct dquot *dquot);
1430 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1431 static int ext4_write_info(struct super_block *sb, int type);
1432 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1433 			 const struct path *path);
1434 static int ext4_quota_on_mount(struct super_block *sb, int type);
1435 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1436 			       size_t len, loff_t off);
1437 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1438 				const char *data, size_t len, loff_t off);
1439 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1440 			     unsigned int flags);
1441 static int ext4_enable_quotas(struct super_block *sb);
1442 
1443 static struct dquot **ext4_get_dquots(struct inode *inode)
1444 {
1445 	return EXT4_I(inode)->i_dquot;
1446 }
1447 
1448 static const struct dquot_operations ext4_quota_operations = {
1449 	.get_reserved_space	= ext4_get_reserved_space,
1450 	.write_dquot		= ext4_write_dquot,
1451 	.acquire_dquot		= ext4_acquire_dquot,
1452 	.release_dquot		= ext4_release_dquot,
1453 	.mark_dirty		= ext4_mark_dquot_dirty,
1454 	.write_info		= ext4_write_info,
1455 	.alloc_dquot		= dquot_alloc,
1456 	.destroy_dquot		= dquot_destroy,
1457 	.get_projid		= ext4_get_projid,
1458 	.get_inode_usage	= ext4_get_inode_usage,
1459 	.get_next_id		= dquot_get_next_id,
1460 };
1461 
1462 static const struct quotactl_ops ext4_qctl_operations = {
1463 	.quota_on	= ext4_quota_on,
1464 	.quota_off	= ext4_quota_off,
1465 	.quota_sync	= dquot_quota_sync,
1466 	.get_state	= dquot_get_state,
1467 	.set_info	= dquot_set_dqinfo,
1468 	.get_dqblk	= dquot_get_dqblk,
1469 	.set_dqblk	= dquot_set_dqblk,
1470 	.get_nextdqblk	= dquot_get_next_dqblk,
1471 };
1472 #endif
1473 
1474 static const struct super_operations ext4_sops = {
1475 	.alloc_inode	= ext4_alloc_inode,
1476 	.free_inode	= ext4_free_in_core_inode,
1477 	.destroy_inode	= ext4_destroy_inode,
1478 	.write_inode	= ext4_write_inode,
1479 	.dirty_inode	= ext4_dirty_inode,
1480 	.drop_inode	= ext4_drop_inode,
1481 	.evict_inode	= ext4_evict_inode,
1482 	.put_super	= ext4_put_super,
1483 	.sync_fs	= ext4_sync_fs,
1484 	.freeze_fs	= ext4_freeze,
1485 	.unfreeze_fs	= ext4_unfreeze,
1486 	.statfs		= ext4_statfs,
1487 	.remount_fs	= ext4_remount,
1488 	.show_options	= ext4_show_options,
1489 #ifdef CONFIG_QUOTA
1490 	.quota_read	= ext4_quota_read,
1491 	.quota_write	= ext4_quota_write,
1492 	.get_dquots	= ext4_get_dquots,
1493 #endif
1494 	.bdev_try_to_free_page = bdev_try_to_free_page,
1495 };
1496 
1497 static const struct export_operations ext4_export_ops = {
1498 	.fh_to_dentry = ext4_fh_to_dentry,
1499 	.fh_to_parent = ext4_fh_to_parent,
1500 	.get_parent = ext4_get_parent,
1501 	.commit_metadata = ext4_nfs_commit_metadata,
1502 };
1503 
1504 enum {
1505 	Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1506 	Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1507 	Opt_nouid32, Opt_debug, Opt_removed,
1508 	Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1509 	Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1510 	Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1511 	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1512 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1513 	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1514 	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1515 	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1516 	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1517 	Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1518 	Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1519 	Opt_nowarn_on_error, Opt_mblk_io_submit,
1520 	Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1521 	Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1522 	Opt_inode_readahead_blks, Opt_journal_ioprio,
1523 	Opt_dioread_nolock, Opt_dioread_lock,
1524 	Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1525 	Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1526 };
1527 
1528 static const match_table_t tokens = {
1529 	{Opt_bsd_df, "bsddf"},
1530 	{Opt_minix_df, "minixdf"},
1531 	{Opt_grpid, "grpid"},
1532 	{Opt_grpid, "bsdgroups"},
1533 	{Opt_nogrpid, "nogrpid"},
1534 	{Opt_nogrpid, "sysvgroups"},
1535 	{Opt_resgid, "resgid=%u"},
1536 	{Opt_resuid, "resuid=%u"},
1537 	{Opt_sb, "sb=%u"},
1538 	{Opt_err_cont, "errors=continue"},
1539 	{Opt_err_panic, "errors=panic"},
1540 	{Opt_err_ro, "errors=remount-ro"},
1541 	{Opt_nouid32, "nouid32"},
1542 	{Opt_debug, "debug"},
1543 	{Opt_removed, "oldalloc"},
1544 	{Opt_removed, "orlov"},
1545 	{Opt_user_xattr, "user_xattr"},
1546 	{Opt_nouser_xattr, "nouser_xattr"},
1547 	{Opt_acl, "acl"},
1548 	{Opt_noacl, "noacl"},
1549 	{Opt_noload, "norecovery"},
1550 	{Opt_noload, "noload"},
1551 	{Opt_removed, "nobh"},
1552 	{Opt_removed, "bh"},
1553 	{Opt_commit, "commit=%u"},
1554 	{Opt_min_batch_time, "min_batch_time=%u"},
1555 	{Opt_max_batch_time, "max_batch_time=%u"},
1556 	{Opt_journal_dev, "journal_dev=%u"},
1557 	{Opt_journal_path, "journal_path=%s"},
1558 	{Opt_journal_checksum, "journal_checksum"},
1559 	{Opt_nojournal_checksum, "nojournal_checksum"},
1560 	{Opt_journal_async_commit, "journal_async_commit"},
1561 	{Opt_abort, "abort"},
1562 	{Opt_data_journal, "data=journal"},
1563 	{Opt_data_ordered, "data=ordered"},
1564 	{Opt_data_writeback, "data=writeback"},
1565 	{Opt_data_err_abort, "data_err=abort"},
1566 	{Opt_data_err_ignore, "data_err=ignore"},
1567 	{Opt_offusrjquota, "usrjquota="},
1568 	{Opt_usrjquota, "usrjquota=%s"},
1569 	{Opt_offgrpjquota, "grpjquota="},
1570 	{Opt_grpjquota, "grpjquota=%s"},
1571 	{Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1572 	{Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1573 	{Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1574 	{Opt_grpquota, "grpquota"},
1575 	{Opt_noquota, "noquota"},
1576 	{Opt_quota, "quota"},
1577 	{Opt_usrquota, "usrquota"},
1578 	{Opt_prjquota, "prjquota"},
1579 	{Opt_barrier, "barrier=%u"},
1580 	{Opt_barrier, "barrier"},
1581 	{Opt_nobarrier, "nobarrier"},
1582 	{Opt_i_version, "i_version"},
1583 	{Opt_dax, "dax"},
1584 	{Opt_stripe, "stripe=%u"},
1585 	{Opt_delalloc, "delalloc"},
1586 	{Opt_warn_on_error, "warn_on_error"},
1587 	{Opt_nowarn_on_error, "nowarn_on_error"},
1588 	{Opt_lazytime, "lazytime"},
1589 	{Opt_nolazytime, "nolazytime"},
1590 	{Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1591 	{Opt_nodelalloc, "nodelalloc"},
1592 	{Opt_removed, "mblk_io_submit"},
1593 	{Opt_removed, "nomblk_io_submit"},
1594 	{Opt_block_validity, "block_validity"},
1595 	{Opt_noblock_validity, "noblock_validity"},
1596 	{Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1597 	{Opt_journal_ioprio, "journal_ioprio=%u"},
1598 	{Opt_auto_da_alloc, "auto_da_alloc=%u"},
1599 	{Opt_auto_da_alloc, "auto_da_alloc"},
1600 	{Opt_noauto_da_alloc, "noauto_da_alloc"},
1601 	{Opt_dioread_nolock, "dioread_nolock"},
1602 	{Opt_dioread_lock, "nodioread_nolock"},
1603 	{Opt_dioread_lock, "dioread_lock"},
1604 	{Opt_discard, "discard"},
1605 	{Opt_nodiscard, "nodiscard"},
1606 	{Opt_init_itable, "init_itable=%u"},
1607 	{Opt_init_itable, "init_itable"},
1608 	{Opt_noinit_itable, "noinit_itable"},
1609 	{Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1610 	{Opt_test_dummy_encryption, "test_dummy_encryption"},
1611 	{Opt_nombcache, "nombcache"},
1612 	{Opt_nombcache, "no_mbcache"},	/* for backward compatibility */
1613 	{Opt_removed, "check=none"},	/* mount option from ext2/3 */
1614 	{Opt_removed, "nocheck"},	/* mount option from ext2/3 */
1615 	{Opt_removed, "reservation"},	/* mount option from ext2/3 */
1616 	{Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1617 	{Opt_removed, "journal=%u"},	/* mount option from ext2/3 */
1618 	{Opt_err, NULL},
1619 };
1620 
1621 static ext4_fsblk_t get_sb_block(void **data)
1622 {
1623 	ext4_fsblk_t	sb_block;
1624 	char		*options = (char *) *data;
1625 
1626 	if (!options || strncmp(options, "sb=", 3) != 0)
1627 		return 1;	/* Default location */
1628 
1629 	options += 3;
1630 	/* TODO: use simple_strtoll with >32bit ext4 */
1631 	sb_block = simple_strtoul(options, &options, 0);
1632 	if (*options && *options != ',') {
1633 		printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1634 		       (char *) *data);
1635 		return 1;
1636 	}
1637 	if (*options == ',')
1638 		options++;
1639 	*data = (void *) options;
1640 
1641 	return sb_block;
1642 }
1643 
1644 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1645 static const char deprecated_msg[] =
1646 	"Mount option \"%s\" will be removed by %s\n"
1647 	"Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1648 
1649 #ifdef CONFIG_QUOTA
1650 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1651 {
1652 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1653 	char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1654 	int ret = -1;
1655 
1656 	if (sb_any_quota_loaded(sb) && !old_qname) {
1657 		ext4_msg(sb, KERN_ERR,
1658 			"Cannot change journaled "
1659 			"quota options when quota turned on");
1660 		return -1;
1661 	}
1662 	if (ext4_has_feature_quota(sb)) {
1663 		ext4_msg(sb, KERN_INFO, "Journaled quota options "
1664 			 "ignored when QUOTA feature is enabled");
1665 		return 1;
1666 	}
1667 	qname = match_strdup(args);
1668 	if (!qname) {
1669 		ext4_msg(sb, KERN_ERR,
1670 			"Not enough memory for storing quotafile name");
1671 		return -1;
1672 	}
1673 	if (old_qname) {
1674 		if (strcmp(old_qname, qname) == 0)
1675 			ret = 1;
1676 		else
1677 			ext4_msg(sb, KERN_ERR,
1678 				 "%s quota file already specified",
1679 				 QTYPE2NAME(qtype));
1680 		goto errout;
1681 	}
1682 	if (strchr(qname, '/')) {
1683 		ext4_msg(sb, KERN_ERR,
1684 			"quotafile must be on filesystem root");
1685 		goto errout;
1686 	}
1687 	rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1688 	set_opt(sb, QUOTA);
1689 	return 1;
1690 errout:
1691 	kfree(qname);
1692 	return ret;
1693 }
1694 
1695 static int clear_qf_name(struct super_block *sb, int qtype)
1696 {
1697 
1698 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1699 	char *old_qname = get_qf_name(sb, sbi, qtype);
1700 
1701 	if (sb_any_quota_loaded(sb) && old_qname) {
1702 		ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1703 			" when quota turned on");
1704 		return -1;
1705 	}
1706 	rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1707 	synchronize_rcu();
1708 	kfree(old_qname);
1709 	return 1;
1710 }
1711 #endif
1712 
1713 #define MOPT_SET	0x0001
1714 #define MOPT_CLEAR	0x0002
1715 #define MOPT_NOSUPPORT	0x0004
1716 #define MOPT_EXPLICIT	0x0008
1717 #define MOPT_CLEAR_ERR	0x0010
1718 #define MOPT_GTE0	0x0020
1719 #ifdef CONFIG_QUOTA
1720 #define MOPT_Q		0
1721 #define MOPT_QFMT	0x0040
1722 #else
1723 #define MOPT_Q		MOPT_NOSUPPORT
1724 #define MOPT_QFMT	MOPT_NOSUPPORT
1725 #endif
1726 #define MOPT_DATAJ	0x0080
1727 #define MOPT_NO_EXT2	0x0100
1728 #define MOPT_NO_EXT3	0x0200
1729 #define MOPT_EXT4_ONLY	(MOPT_NO_EXT2 | MOPT_NO_EXT3)
1730 #define MOPT_STRING	0x0400
1731 
1732 static const struct mount_opts {
1733 	int	token;
1734 	int	mount_opt;
1735 	int	flags;
1736 } ext4_mount_opts[] = {
1737 	{Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1738 	{Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1739 	{Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1740 	{Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1741 	{Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1742 	{Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1743 	{Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1744 	 MOPT_EXT4_ONLY | MOPT_SET},
1745 	{Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1746 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1747 	{Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1748 	{Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1749 	{Opt_delalloc, EXT4_MOUNT_DELALLOC,
1750 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1751 	{Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1752 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1753 	{Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1754 	{Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1755 	{Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1756 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1757 	{Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1758 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1759 	{Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1760 				    EXT4_MOUNT_JOURNAL_CHECKSUM),
1761 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1762 	{Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1763 	{Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1764 	{Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1765 	{Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1766 	{Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1767 	 MOPT_NO_EXT2},
1768 	{Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1769 	 MOPT_NO_EXT2},
1770 	{Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1771 	{Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1772 	{Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1773 	{Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1774 	{Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1775 	{Opt_commit, 0, MOPT_GTE0},
1776 	{Opt_max_batch_time, 0, MOPT_GTE0},
1777 	{Opt_min_batch_time, 0, MOPT_GTE0},
1778 	{Opt_inode_readahead_blks, 0, MOPT_GTE0},
1779 	{Opt_init_itable, 0, MOPT_GTE0},
1780 	{Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1781 	{Opt_stripe, 0, MOPT_GTE0},
1782 	{Opt_resuid, 0, MOPT_GTE0},
1783 	{Opt_resgid, 0, MOPT_GTE0},
1784 	{Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1785 	{Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1786 	{Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1787 	{Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1788 	{Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1789 	{Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1790 	 MOPT_NO_EXT2 | MOPT_DATAJ},
1791 	{Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1792 	{Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1793 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1794 	{Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1795 	{Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1796 #else
1797 	{Opt_acl, 0, MOPT_NOSUPPORT},
1798 	{Opt_noacl, 0, MOPT_NOSUPPORT},
1799 #endif
1800 	{Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1801 	{Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1802 	{Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1803 	{Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1804 	{Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1805 							MOPT_SET | MOPT_Q},
1806 	{Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1807 							MOPT_SET | MOPT_Q},
1808 	{Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1809 							MOPT_SET | MOPT_Q},
1810 	{Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1811 		       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1812 							MOPT_CLEAR | MOPT_Q},
1813 	{Opt_usrjquota, 0, MOPT_Q},
1814 	{Opt_grpjquota, 0, MOPT_Q},
1815 	{Opt_offusrjquota, 0, MOPT_Q},
1816 	{Opt_offgrpjquota, 0, MOPT_Q},
1817 	{Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1818 	{Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1819 	{Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1820 	{Opt_max_dir_size_kb, 0, MOPT_GTE0},
1821 	{Opt_test_dummy_encryption, 0, MOPT_GTE0},
1822 	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1823 	{Opt_err, 0, 0}
1824 };
1825 
1826 #ifdef CONFIG_UNICODE
1827 static const struct ext4_sb_encodings {
1828 	__u16 magic;
1829 	char *name;
1830 	char *version;
1831 } ext4_sb_encoding_map[] = {
1832 	{EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1833 };
1834 
1835 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1836 				 const struct ext4_sb_encodings **encoding,
1837 				 __u16 *flags)
1838 {
1839 	__u16 magic = le16_to_cpu(es->s_encoding);
1840 	int i;
1841 
1842 	for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1843 		if (magic == ext4_sb_encoding_map[i].magic)
1844 			break;
1845 
1846 	if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1847 		return -EINVAL;
1848 
1849 	*encoding = &ext4_sb_encoding_map[i];
1850 	*flags = le16_to_cpu(es->s_encoding_flags);
1851 
1852 	return 0;
1853 }
1854 #endif
1855 
1856 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1857 			    substring_t *args, unsigned long *journal_devnum,
1858 			    unsigned int *journal_ioprio, int is_remount)
1859 {
1860 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1861 	const struct mount_opts *m;
1862 	kuid_t uid;
1863 	kgid_t gid;
1864 	int arg = 0;
1865 
1866 #ifdef CONFIG_QUOTA
1867 	if (token == Opt_usrjquota)
1868 		return set_qf_name(sb, USRQUOTA, &args[0]);
1869 	else if (token == Opt_grpjquota)
1870 		return set_qf_name(sb, GRPQUOTA, &args[0]);
1871 	else if (token == Opt_offusrjquota)
1872 		return clear_qf_name(sb, USRQUOTA);
1873 	else if (token == Opt_offgrpjquota)
1874 		return clear_qf_name(sb, GRPQUOTA);
1875 #endif
1876 	switch (token) {
1877 	case Opt_noacl:
1878 	case Opt_nouser_xattr:
1879 		ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1880 		break;
1881 	case Opt_sb:
1882 		return 1;	/* handled by get_sb_block() */
1883 	case Opt_removed:
1884 		ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1885 		return 1;
1886 	case Opt_abort:
1887 		sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1888 		return 1;
1889 	case Opt_i_version:
1890 		sb->s_flags |= SB_I_VERSION;
1891 		return 1;
1892 	case Opt_lazytime:
1893 		sb->s_flags |= SB_LAZYTIME;
1894 		return 1;
1895 	case Opt_nolazytime:
1896 		sb->s_flags &= ~SB_LAZYTIME;
1897 		return 1;
1898 	}
1899 
1900 	for (m = ext4_mount_opts; m->token != Opt_err; m++)
1901 		if (token == m->token)
1902 			break;
1903 
1904 	if (m->token == Opt_err) {
1905 		ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1906 			 "or missing value", opt);
1907 		return -1;
1908 	}
1909 
1910 	if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1911 		ext4_msg(sb, KERN_ERR,
1912 			 "Mount option \"%s\" incompatible with ext2", opt);
1913 		return -1;
1914 	}
1915 	if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1916 		ext4_msg(sb, KERN_ERR,
1917 			 "Mount option \"%s\" incompatible with ext3", opt);
1918 		return -1;
1919 	}
1920 
1921 	if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1922 		return -1;
1923 	if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1924 		return -1;
1925 	if (m->flags & MOPT_EXPLICIT) {
1926 		if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1927 			set_opt2(sb, EXPLICIT_DELALLOC);
1928 		} else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1929 			set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1930 		} else
1931 			return -1;
1932 	}
1933 	if (m->flags & MOPT_CLEAR_ERR)
1934 		clear_opt(sb, ERRORS_MASK);
1935 	if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1936 		ext4_msg(sb, KERN_ERR, "Cannot change quota "
1937 			 "options when quota turned on");
1938 		return -1;
1939 	}
1940 
1941 	if (m->flags & MOPT_NOSUPPORT) {
1942 		ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1943 	} else if (token == Opt_commit) {
1944 		if (arg == 0)
1945 			arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1946 		else if (arg > INT_MAX / HZ) {
1947 			ext4_msg(sb, KERN_ERR,
1948 				 "Invalid commit interval %d, "
1949 				 "must be smaller than %d",
1950 				 arg, INT_MAX / HZ);
1951 			return -1;
1952 		}
1953 		sbi->s_commit_interval = HZ * arg;
1954 	} else if (token == Opt_debug_want_extra_isize) {
1955 		if ((arg & 1) ||
1956 		    (arg < 4) ||
1957 		    (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
1958 			ext4_msg(sb, KERN_ERR,
1959 				 "Invalid want_extra_isize %d", arg);
1960 			return -1;
1961 		}
1962 		sbi->s_want_extra_isize = arg;
1963 	} else if (token == Opt_max_batch_time) {
1964 		sbi->s_max_batch_time = arg;
1965 	} else if (token == Opt_min_batch_time) {
1966 		sbi->s_min_batch_time = arg;
1967 	} else if (token == Opt_inode_readahead_blks) {
1968 		if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1969 			ext4_msg(sb, KERN_ERR,
1970 				 "EXT4-fs: inode_readahead_blks must be "
1971 				 "0 or a power of 2 smaller than 2^31");
1972 			return -1;
1973 		}
1974 		sbi->s_inode_readahead_blks = arg;
1975 	} else if (token == Opt_init_itable) {
1976 		set_opt(sb, INIT_INODE_TABLE);
1977 		if (!args->from)
1978 			arg = EXT4_DEF_LI_WAIT_MULT;
1979 		sbi->s_li_wait_mult = arg;
1980 	} else if (token == Opt_max_dir_size_kb) {
1981 		sbi->s_max_dir_size_kb = arg;
1982 	} else if (token == Opt_stripe) {
1983 		sbi->s_stripe = arg;
1984 	} else if (token == Opt_resuid) {
1985 		uid = make_kuid(current_user_ns(), arg);
1986 		if (!uid_valid(uid)) {
1987 			ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1988 			return -1;
1989 		}
1990 		sbi->s_resuid = uid;
1991 	} else if (token == Opt_resgid) {
1992 		gid = make_kgid(current_user_ns(), arg);
1993 		if (!gid_valid(gid)) {
1994 			ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1995 			return -1;
1996 		}
1997 		sbi->s_resgid = gid;
1998 	} else if (token == Opt_journal_dev) {
1999 		if (is_remount) {
2000 			ext4_msg(sb, KERN_ERR,
2001 				 "Cannot specify journal on remount");
2002 			return -1;
2003 		}
2004 		*journal_devnum = arg;
2005 	} else if (token == Opt_journal_path) {
2006 		char *journal_path;
2007 		struct inode *journal_inode;
2008 		struct path path;
2009 		int error;
2010 
2011 		if (is_remount) {
2012 			ext4_msg(sb, KERN_ERR,
2013 				 "Cannot specify journal on remount");
2014 			return -1;
2015 		}
2016 		journal_path = match_strdup(&args[0]);
2017 		if (!journal_path) {
2018 			ext4_msg(sb, KERN_ERR, "error: could not dup "
2019 				"journal device string");
2020 			return -1;
2021 		}
2022 
2023 		error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2024 		if (error) {
2025 			ext4_msg(sb, KERN_ERR, "error: could not find "
2026 				"journal device path: error %d", error);
2027 			kfree(journal_path);
2028 			return -1;
2029 		}
2030 
2031 		journal_inode = d_inode(path.dentry);
2032 		if (!S_ISBLK(journal_inode->i_mode)) {
2033 			ext4_msg(sb, KERN_ERR, "error: journal path %s "
2034 				"is not a block device", journal_path);
2035 			path_put(&path);
2036 			kfree(journal_path);
2037 			return -1;
2038 		}
2039 
2040 		*journal_devnum = new_encode_dev(journal_inode->i_rdev);
2041 		path_put(&path);
2042 		kfree(journal_path);
2043 	} else if (token == Opt_journal_ioprio) {
2044 		if (arg > 7) {
2045 			ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2046 				 " (must be 0-7)");
2047 			return -1;
2048 		}
2049 		*journal_ioprio =
2050 			IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2051 	} else if (token == Opt_test_dummy_encryption) {
2052 #ifdef CONFIG_FS_ENCRYPTION
2053 		sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
2054 		ext4_msg(sb, KERN_WARNING,
2055 			 "Test dummy encryption mode enabled");
2056 #else
2057 		ext4_msg(sb, KERN_WARNING,
2058 			 "Test dummy encryption mount option ignored");
2059 #endif
2060 	} else if (m->flags & MOPT_DATAJ) {
2061 		if (is_remount) {
2062 			if (!sbi->s_journal)
2063 				ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2064 			else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2065 				ext4_msg(sb, KERN_ERR,
2066 					 "Cannot change data mode on remount");
2067 				return -1;
2068 			}
2069 		} else {
2070 			clear_opt(sb, DATA_FLAGS);
2071 			sbi->s_mount_opt |= m->mount_opt;
2072 		}
2073 #ifdef CONFIG_QUOTA
2074 	} else if (m->flags & MOPT_QFMT) {
2075 		if (sb_any_quota_loaded(sb) &&
2076 		    sbi->s_jquota_fmt != m->mount_opt) {
2077 			ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2078 				 "quota options when quota turned on");
2079 			return -1;
2080 		}
2081 		if (ext4_has_feature_quota(sb)) {
2082 			ext4_msg(sb, KERN_INFO,
2083 				 "Quota format mount options ignored "
2084 				 "when QUOTA feature is enabled");
2085 			return 1;
2086 		}
2087 		sbi->s_jquota_fmt = m->mount_opt;
2088 #endif
2089 	} else if (token == Opt_dax) {
2090 #ifdef CONFIG_FS_DAX
2091 		ext4_msg(sb, KERN_WARNING,
2092 		"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2093 		sbi->s_mount_opt |= m->mount_opt;
2094 #else
2095 		ext4_msg(sb, KERN_INFO, "dax option not supported");
2096 		return -1;
2097 #endif
2098 	} else if (token == Opt_data_err_abort) {
2099 		sbi->s_mount_opt |= m->mount_opt;
2100 	} else if (token == Opt_data_err_ignore) {
2101 		sbi->s_mount_opt &= ~m->mount_opt;
2102 	} else {
2103 		if (!args->from)
2104 			arg = 1;
2105 		if (m->flags & MOPT_CLEAR)
2106 			arg = !arg;
2107 		else if (unlikely(!(m->flags & MOPT_SET))) {
2108 			ext4_msg(sb, KERN_WARNING,
2109 				 "buggy handling of option %s", opt);
2110 			WARN_ON(1);
2111 			return -1;
2112 		}
2113 		if (arg != 0)
2114 			sbi->s_mount_opt |= m->mount_opt;
2115 		else
2116 			sbi->s_mount_opt &= ~m->mount_opt;
2117 	}
2118 	return 1;
2119 }
2120 
2121 static int parse_options(char *options, struct super_block *sb,
2122 			 unsigned long *journal_devnum,
2123 			 unsigned int *journal_ioprio,
2124 			 int is_remount)
2125 {
2126 	struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2127 	char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2128 	substring_t args[MAX_OPT_ARGS];
2129 	int token;
2130 
2131 	if (!options)
2132 		return 1;
2133 
2134 	while ((p = strsep(&options, ",")) != NULL) {
2135 		if (!*p)
2136 			continue;
2137 		/*
2138 		 * Initialize args struct so we know whether arg was
2139 		 * found; some options take optional arguments.
2140 		 */
2141 		args[0].to = args[0].from = NULL;
2142 		token = match_token(p, tokens, args);
2143 		if (handle_mount_opt(sb, p, token, args, journal_devnum,
2144 				     journal_ioprio, is_remount) < 0)
2145 			return 0;
2146 	}
2147 #ifdef CONFIG_QUOTA
2148 	/*
2149 	 * We do the test below only for project quotas. 'usrquota' and
2150 	 * 'grpquota' mount options are allowed even without quota feature
2151 	 * to support legacy quotas in quota files.
2152 	 */
2153 	if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2154 		ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2155 			 "Cannot enable project quota enforcement.");
2156 		return 0;
2157 	}
2158 	usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2159 	grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2160 	if (usr_qf_name || grp_qf_name) {
2161 		if (test_opt(sb, USRQUOTA) && usr_qf_name)
2162 			clear_opt(sb, USRQUOTA);
2163 
2164 		if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2165 			clear_opt(sb, GRPQUOTA);
2166 
2167 		if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2168 			ext4_msg(sb, KERN_ERR, "old and new quota "
2169 					"format mixing");
2170 			return 0;
2171 		}
2172 
2173 		if (!sbi->s_jquota_fmt) {
2174 			ext4_msg(sb, KERN_ERR, "journaled quota format "
2175 					"not specified");
2176 			return 0;
2177 		}
2178 	}
2179 #endif
2180 	if (test_opt(sb, DIOREAD_NOLOCK)) {
2181 		int blocksize =
2182 			BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2183 		if (blocksize < PAGE_SIZE)
2184 			ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2185 				 "experimental mount option 'dioread_nolock' "
2186 				 "for blocksize < PAGE_SIZE");
2187 	}
2188 	return 1;
2189 }
2190 
2191 static inline void ext4_show_quota_options(struct seq_file *seq,
2192 					   struct super_block *sb)
2193 {
2194 #if defined(CONFIG_QUOTA)
2195 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2196 	char *usr_qf_name, *grp_qf_name;
2197 
2198 	if (sbi->s_jquota_fmt) {
2199 		char *fmtname = "";
2200 
2201 		switch (sbi->s_jquota_fmt) {
2202 		case QFMT_VFS_OLD:
2203 			fmtname = "vfsold";
2204 			break;
2205 		case QFMT_VFS_V0:
2206 			fmtname = "vfsv0";
2207 			break;
2208 		case QFMT_VFS_V1:
2209 			fmtname = "vfsv1";
2210 			break;
2211 		}
2212 		seq_printf(seq, ",jqfmt=%s", fmtname);
2213 	}
2214 
2215 	rcu_read_lock();
2216 	usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2217 	grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2218 	if (usr_qf_name)
2219 		seq_show_option(seq, "usrjquota", usr_qf_name);
2220 	if (grp_qf_name)
2221 		seq_show_option(seq, "grpjquota", grp_qf_name);
2222 	rcu_read_unlock();
2223 #endif
2224 }
2225 
2226 static const char *token2str(int token)
2227 {
2228 	const struct match_token *t;
2229 
2230 	for (t = tokens; t->token != Opt_err; t++)
2231 		if (t->token == token && !strchr(t->pattern, '='))
2232 			break;
2233 	return t->pattern;
2234 }
2235 
2236 /*
2237  * Show an option if
2238  *  - it's set to a non-default value OR
2239  *  - if the per-sb default is different from the global default
2240  */
2241 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2242 			      int nodefs)
2243 {
2244 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2245 	struct ext4_super_block *es = sbi->s_es;
2246 	int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2247 	const struct mount_opts *m;
2248 	char sep = nodefs ? '\n' : ',';
2249 
2250 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2251 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2252 
2253 	if (sbi->s_sb_block != 1)
2254 		SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2255 
2256 	for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2257 		int want_set = m->flags & MOPT_SET;
2258 		if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2259 		    (m->flags & MOPT_CLEAR_ERR))
2260 			continue;
2261 		if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2262 			continue; /* skip if same as the default */
2263 		if ((want_set &&
2264 		     (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2265 		    (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2266 			continue; /* select Opt_noFoo vs Opt_Foo */
2267 		SEQ_OPTS_PRINT("%s", token2str(m->token));
2268 	}
2269 
2270 	if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2271 	    le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2272 		SEQ_OPTS_PRINT("resuid=%u",
2273 				from_kuid_munged(&init_user_ns, sbi->s_resuid));
2274 	if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2275 	    le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2276 		SEQ_OPTS_PRINT("resgid=%u",
2277 				from_kgid_munged(&init_user_ns, sbi->s_resgid));
2278 	def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2279 	if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2280 		SEQ_OPTS_PUTS("errors=remount-ro");
2281 	if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2282 		SEQ_OPTS_PUTS("errors=continue");
2283 	if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2284 		SEQ_OPTS_PUTS("errors=panic");
2285 	if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2286 		SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2287 	if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2288 		SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2289 	if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2290 		SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2291 	if (sb->s_flags & SB_I_VERSION)
2292 		SEQ_OPTS_PUTS("i_version");
2293 	if (nodefs || sbi->s_stripe)
2294 		SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2295 	if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2296 			(sbi->s_mount_opt ^ def_mount_opt)) {
2297 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2298 			SEQ_OPTS_PUTS("data=journal");
2299 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2300 			SEQ_OPTS_PUTS("data=ordered");
2301 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2302 			SEQ_OPTS_PUTS("data=writeback");
2303 	}
2304 	if (nodefs ||
2305 	    sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2306 		SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2307 			       sbi->s_inode_readahead_blks);
2308 
2309 	if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2310 		       (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2311 		SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2312 	if (nodefs || sbi->s_max_dir_size_kb)
2313 		SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2314 	if (test_opt(sb, DATA_ERR_ABORT))
2315 		SEQ_OPTS_PUTS("data_err=abort");
2316 	if (DUMMY_ENCRYPTION_ENABLED(sbi))
2317 		SEQ_OPTS_PUTS("test_dummy_encryption");
2318 
2319 	ext4_show_quota_options(seq, sb);
2320 	return 0;
2321 }
2322 
2323 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2324 {
2325 	return _ext4_show_options(seq, root->d_sb, 0);
2326 }
2327 
2328 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2329 {
2330 	struct super_block *sb = seq->private;
2331 	int rc;
2332 
2333 	seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2334 	rc = _ext4_show_options(seq, sb, 1);
2335 	seq_puts(seq, "\n");
2336 	return rc;
2337 }
2338 
2339 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2340 			    int read_only)
2341 {
2342 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2343 	int err = 0;
2344 
2345 	if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2346 		ext4_msg(sb, KERN_ERR, "revision level too high, "
2347 			 "forcing read-only mode");
2348 		err = -EROFS;
2349 	}
2350 	if (read_only)
2351 		goto done;
2352 	if (!(sbi->s_mount_state & EXT4_VALID_FS))
2353 		ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2354 			 "running e2fsck is recommended");
2355 	else if (sbi->s_mount_state & EXT4_ERROR_FS)
2356 		ext4_msg(sb, KERN_WARNING,
2357 			 "warning: mounting fs with errors, "
2358 			 "running e2fsck is recommended");
2359 	else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2360 		 le16_to_cpu(es->s_mnt_count) >=
2361 		 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2362 		ext4_msg(sb, KERN_WARNING,
2363 			 "warning: maximal mount count reached, "
2364 			 "running e2fsck is recommended");
2365 	else if (le32_to_cpu(es->s_checkinterval) &&
2366 		 (ext4_get_tstamp(es, s_lastcheck) +
2367 		  le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2368 		ext4_msg(sb, KERN_WARNING,
2369 			 "warning: checktime reached, "
2370 			 "running e2fsck is recommended");
2371 	if (!sbi->s_journal)
2372 		es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2373 	if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2374 		es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2375 	le16_add_cpu(&es->s_mnt_count, 1);
2376 	ext4_update_tstamp(es, s_mtime);
2377 	if (sbi->s_journal)
2378 		ext4_set_feature_journal_needs_recovery(sb);
2379 
2380 	err = ext4_commit_super(sb, 1);
2381 done:
2382 	if (test_opt(sb, DEBUG))
2383 		printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2384 				"bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2385 			sb->s_blocksize,
2386 			sbi->s_groups_count,
2387 			EXT4_BLOCKS_PER_GROUP(sb),
2388 			EXT4_INODES_PER_GROUP(sb),
2389 			sbi->s_mount_opt, sbi->s_mount_opt2);
2390 
2391 	cleancache_init_fs(sb);
2392 	return err;
2393 }
2394 
2395 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2396 {
2397 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2398 	struct flex_groups **old_groups, **new_groups;
2399 	int size, i, j;
2400 
2401 	if (!sbi->s_log_groups_per_flex)
2402 		return 0;
2403 
2404 	size = ext4_flex_group(sbi, ngroup - 1) + 1;
2405 	if (size <= sbi->s_flex_groups_allocated)
2406 		return 0;
2407 
2408 	new_groups = kvzalloc(roundup_pow_of_two(size *
2409 			      sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2410 	if (!new_groups) {
2411 		ext4_msg(sb, KERN_ERR,
2412 			 "not enough memory for %d flex group pointers", size);
2413 		return -ENOMEM;
2414 	}
2415 	for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2416 		new_groups[i] = kvzalloc(roundup_pow_of_two(
2417 					 sizeof(struct flex_groups)),
2418 					 GFP_KERNEL);
2419 		if (!new_groups[i]) {
2420 			for (j = sbi->s_flex_groups_allocated; j < i; j++)
2421 				kvfree(new_groups[j]);
2422 			kvfree(new_groups);
2423 			ext4_msg(sb, KERN_ERR,
2424 				 "not enough memory for %d flex groups", size);
2425 			return -ENOMEM;
2426 		}
2427 	}
2428 	rcu_read_lock();
2429 	old_groups = rcu_dereference(sbi->s_flex_groups);
2430 	if (old_groups)
2431 		memcpy(new_groups, old_groups,
2432 		       (sbi->s_flex_groups_allocated *
2433 			sizeof(struct flex_groups *)));
2434 	rcu_read_unlock();
2435 	rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2436 	sbi->s_flex_groups_allocated = size;
2437 	if (old_groups)
2438 		ext4_kvfree_array_rcu(old_groups);
2439 	return 0;
2440 }
2441 
2442 static int ext4_fill_flex_info(struct super_block *sb)
2443 {
2444 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2445 	struct ext4_group_desc *gdp = NULL;
2446 	struct flex_groups *fg;
2447 	ext4_group_t flex_group;
2448 	int i, err;
2449 
2450 	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2451 	if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2452 		sbi->s_log_groups_per_flex = 0;
2453 		return 1;
2454 	}
2455 
2456 	err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2457 	if (err)
2458 		goto failed;
2459 
2460 	for (i = 0; i < sbi->s_groups_count; i++) {
2461 		gdp = ext4_get_group_desc(sb, i, NULL);
2462 
2463 		flex_group = ext4_flex_group(sbi, i);
2464 		fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2465 		atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2466 		atomic64_add(ext4_free_group_clusters(sb, gdp),
2467 			     &fg->free_clusters);
2468 		atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2469 	}
2470 
2471 	return 1;
2472 failed:
2473 	return 0;
2474 }
2475 
2476 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2477 				   struct ext4_group_desc *gdp)
2478 {
2479 	int offset = offsetof(struct ext4_group_desc, bg_checksum);
2480 	__u16 crc = 0;
2481 	__le32 le_group = cpu_to_le32(block_group);
2482 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2483 
2484 	if (ext4_has_metadata_csum(sbi->s_sb)) {
2485 		/* Use new metadata_csum algorithm */
2486 		__u32 csum32;
2487 		__u16 dummy_csum = 0;
2488 
2489 		csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2490 				     sizeof(le_group));
2491 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2492 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2493 				     sizeof(dummy_csum));
2494 		offset += sizeof(dummy_csum);
2495 		if (offset < sbi->s_desc_size)
2496 			csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2497 					     sbi->s_desc_size - offset);
2498 
2499 		crc = csum32 & 0xFFFF;
2500 		goto out;
2501 	}
2502 
2503 	/* old crc16 code */
2504 	if (!ext4_has_feature_gdt_csum(sb))
2505 		return 0;
2506 
2507 	crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2508 	crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2509 	crc = crc16(crc, (__u8 *)gdp, offset);
2510 	offset += sizeof(gdp->bg_checksum); /* skip checksum */
2511 	/* for checksum of struct ext4_group_desc do the rest...*/
2512 	if (ext4_has_feature_64bit(sb) &&
2513 	    offset < le16_to_cpu(sbi->s_es->s_desc_size))
2514 		crc = crc16(crc, (__u8 *)gdp + offset,
2515 			    le16_to_cpu(sbi->s_es->s_desc_size) -
2516 				offset);
2517 
2518 out:
2519 	return cpu_to_le16(crc);
2520 }
2521 
2522 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2523 				struct ext4_group_desc *gdp)
2524 {
2525 	if (ext4_has_group_desc_csum(sb) &&
2526 	    (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2527 		return 0;
2528 
2529 	return 1;
2530 }
2531 
2532 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2533 			      struct ext4_group_desc *gdp)
2534 {
2535 	if (!ext4_has_group_desc_csum(sb))
2536 		return;
2537 	gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2538 }
2539 
2540 /* Called at mount-time, super-block is locked */
2541 static int ext4_check_descriptors(struct super_block *sb,
2542 				  ext4_fsblk_t sb_block,
2543 				  ext4_group_t *first_not_zeroed)
2544 {
2545 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2546 	ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2547 	ext4_fsblk_t last_block;
2548 	ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2549 	ext4_fsblk_t block_bitmap;
2550 	ext4_fsblk_t inode_bitmap;
2551 	ext4_fsblk_t inode_table;
2552 	int flexbg_flag = 0;
2553 	ext4_group_t i, grp = sbi->s_groups_count;
2554 
2555 	if (ext4_has_feature_flex_bg(sb))
2556 		flexbg_flag = 1;
2557 
2558 	ext4_debug("Checking group descriptors");
2559 
2560 	for (i = 0; i < sbi->s_groups_count; i++) {
2561 		struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2562 
2563 		if (i == sbi->s_groups_count - 1 || flexbg_flag)
2564 			last_block = ext4_blocks_count(sbi->s_es) - 1;
2565 		else
2566 			last_block = first_block +
2567 				(EXT4_BLOCKS_PER_GROUP(sb) - 1);
2568 
2569 		if ((grp == sbi->s_groups_count) &&
2570 		   !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2571 			grp = i;
2572 
2573 		block_bitmap = ext4_block_bitmap(sb, gdp);
2574 		if (block_bitmap == sb_block) {
2575 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2576 				 "Block bitmap for group %u overlaps "
2577 				 "superblock", i);
2578 			if (!sb_rdonly(sb))
2579 				return 0;
2580 		}
2581 		if (block_bitmap >= sb_block + 1 &&
2582 		    block_bitmap <= last_bg_block) {
2583 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2584 				 "Block bitmap for group %u overlaps "
2585 				 "block group descriptors", i);
2586 			if (!sb_rdonly(sb))
2587 				return 0;
2588 		}
2589 		if (block_bitmap < first_block || block_bitmap > last_block) {
2590 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2591 			       "Block bitmap for group %u not in group "
2592 			       "(block %llu)!", i, block_bitmap);
2593 			return 0;
2594 		}
2595 		inode_bitmap = ext4_inode_bitmap(sb, gdp);
2596 		if (inode_bitmap == sb_block) {
2597 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2598 				 "Inode bitmap for group %u overlaps "
2599 				 "superblock", i);
2600 			if (!sb_rdonly(sb))
2601 				return 0;
2602 		}
2603 		if (inode_bitmap >= sb_block + 1 &&
2604 		    inode_bitmap <= last_bg_block) {
2605 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2606 				 "Inode bitmap for group %u overlaps "
2607 				 "block group descriptors", i);
2608 			if (!sb_rdonly(sb))
2609 				return 0;
2610 		}
2611 		if (inode_bitmap < first_block || inode_bitmap > last_block) {
2612 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2613 			       "Inode bitmap for group %u not in group "
2614 			       "(block %llu)!", i, inode_bitmap);
2615 			return 0;
2616 		}
2617 		inode_table = ext4_inode_table(sb, gdp);
2618 		if (inode_table == sb_block) {
2619 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2620 				 "Inode table for group %u overlaps "
2621 				 "superblock", i);
2622 			if (!sb_rdonly(sb))
2623 				return 0;
2624 		}
2625 		if (inode_table >= sb_block + 1 &&
2626 		    inode_table <= last_bg_block) {
2627 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2628 				 "Inode table for group %u overlaps "
2629 				 "block group descriptors", i);
2630 			if (!sb_rdonly(sb))
2631 				return 0;
2632 		}
2633 		if (inode_table < first_block ||
2634 		    inode_table + sbi->s_itb_per_group - 1 > last_block) {
2635 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2636 			       "Inode table for group %u not in group "
2637 			       "(block %llu)!", i, inode_table);
2638 			return 0;
2639 		}
2640 		ext4_lock_group(sb, i);
2641 		if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2642 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2643 				 "Checksum for group %u failed (%u!=%u)",
2644 				 i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2645 				     gdp)), le16_to_cpu(gdp->bg_checksum));
2646 			if (!sb_rdonly(sb)) {
2647 				ext4_unlock_group(sb, i);
2648 				return 0;
2649 			}
2650 		}
2651 		ext4_unlock_group(sb, i);
2652 		if (!flexbg_flag)
2653 			first_block += EXT4_BLOCKS_PER_GROUP(sb);
2654 	}
2655 	if (NULL != first_not_zeroed)
2656 		*first_not_zeroed = grp;
2657 	return 1;
2658 }
2659 
2660 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2661  * the superblock) which were deleted from all directories, but held open by
2662  * a process at the time of a crash.  We walk the list and try to delete these
2663  * inodes at recovery time (only with a read-write filesystem).
2664  *
2665  * In order to keep the orphan inode chain consistent during traversal (in
2666  * case of crash during recovery), we link each inode into the superblock
2667  * orphan list_head and handle it the same way as an inode deletion during
2668  * normal operation (which journals the operations for us).
2669  *
2670  * We only do an iget() and an iput() on each inode, which is very safe if we
2671  * accidentally point at an in-use or already deleted inode.  The worst that
2672  * can happen in this case is that we get a "bit already cleared" message from
2673  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2674  * e2fsck was run on this filesystem, and it must have already done the orphan
2675  * inode cleanup for us, so we can safely abort without any further action.
2676  */
2677 static void ext4_orphan_cleanup(struct super_block *sb,
2678 				struct ext4_super_block *es)
2679 {
2680 	unsigned int s_flags = sb->s_flags;
2681 	int ret, nr_orphans = 0, nr_truncates = 0;
2682 #ifdef CONFIG_QUOTA
2683 	int quota_update = 0;
2684 	int i;
2685 #endif
2686 	if (!es->s_last_orphan) {
2687 		jbd_debug(4, "no orphan inodes to clean up\n");
2688 		return;
2689 	}
2690 
2691 	if (bdev_read_only(sb->s_bdev)) {
2692 		ext4_msg(sb, KERN_ERR, "write access "
2693 			"unavailable, skipping orphan cleanup");
2694 		return;
2695 	}
2696 
2697 	/* Check if feature set would not allow a r/w mount */
2698 	if (!ext4_feature_set_ok(sb, 0)) {
2699 		ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2700 			 "unknown ROCOMPAT features");
2701 		return;
2702 	}
2703 
2704 	if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2705 		/* don't clear list on RO mount w/ errors */
2706 		if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2707 			ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2708 				  "clearing orphan list.\n");
2709 			es->s_last_orphan = 0;
2710 		}
2711 		jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2712 		return;
2713 	}
2714 
2715 	if (s_flags & SB_RDONLY) {
2716 		ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2717 		sb->s_flags &= ~SB_RDONLY;
2718 	}
2719 #ifdef CONFIG_QUOTA
2720 	/* Needed for iput() to work correctly and not trash data */
2721 	sb->s_flags |= SB_ACTIVE;
2722 
2723 	/*
2724 	 * Turn on quotas which were not enabled for read-only mounts if
2725 	 * filesystem has quota feature, so that they are updated correctly.
2726 	 */
2727 	if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2728 		int ret = ext4_enable_quotas(sb);
2729 
2730 		if (!ret)
2731 			quota_update = 1;
2732 		else
2733 			ext4_msg(sb, KERN_ERR,
2734 				"Cannot turn on quotas: error %d", ret);
2735 	}
2736 
2737 	/* Turn on journaled quotas used for old sytle */
2738 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2739 		if (EXT4_SB(sb)->s_qf_names[i]) {
2740 			int ret = ext4_quota_on_mount(sb, i);
2741 
2742 			if (!ret)
2743 				quota_update = 1;
2744 			else
2745 				ext4_msg(sb, KERN_ERR,
2746 					"Cannot turn on journaled "
2747 					"quota: type %d: error %d", i, ret);
2748 		}
2749 	}
2750 #endif
2751 
2752 	while (es->s_last_orphan) {
2753 		struct inode *inode;
2754 
2755 		/*
2756 		 * We may have encountered an error during cleanup; if
2757 		 * so, skip the rest.
2758 		 */
2759 		if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2760 			jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2761 			es->s_last_orphan = 0;
2762 			break;
2763 		}
2764 
2765 		inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2766 		if (IS_ERR(inode)) {
2767 			es->s_last_orphan = 0;
2768 			break;
2769 		}
2770 
2771 		list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2772 		dquot_initialize(inode);
2773 		if (inode->i_nlink) {
2774 			if (test_opt(sb, DEBUG))
2775 				ext4_msg(sb, KERN_DEBUG,
2776 					"%s: truncating inode %lu to %lld bytes",
2777 					__func__, inode->i_ino, inode->i_size);
2778 			jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2779 				  inode->i_ino, inode->i_size);
2780 			inode_lock(inode);
2781 			truncate_inode_pages(inode->i_mapping, inode->i_size);
2782 			ret = ext4_truncate(inode);
2783 			if (ret)
2784 				ext4_std_error(inode->i_sb, ret);
2785 			inode_unlock(inode);
2786 			nr_truncates++;
2787 		} else {
2788 			if (test_opt(sb, DEBUG))
2789 				ext4_msg(sb, KERN_DEBUG,
2790 					"%s: deleting unreferenced inode %lu",
2791 					__func__, inode->i_ino);
2792 			jbd_debug(2, "deleting unreferenced inode %lu\n",
2793 				  inode->i_ino);
2794 			nr_orphans++;
2795 		}
2796 		iput(inode);  /* The delete magic happens here! */
2797 	}
2798 
2799 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2800 
2801 	if (nr_orphans)
2802 		ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2803 		       PLURAL(nr_orphans));
2804 	if (nr_truncates)
2805 		ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2806 		       PLURAL(nr_truncates));
2807 #ifdef CONFIG_QUOTA
2808 	/* Turn off quotas if they were enabled for orphan cleanup */
2809 	if (quota_update) {
2810 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2811 			if (sb_dqopt(sb)->files[i])
2812 				dquot_quota_off(sb, i);
2813 		}
2814 	}
2815 #endif
2816 	sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2817 }
2818 
2819 /*
2820  * Maximal extent format file size.
2821  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2822  * extent format containers, within a sector_t, and within i_blocks
2823  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2824  * so that won't be a limiting factor.
2825  *
2826  * However there is other limiting factor. We do store extents in the form
2827  * of starting block and length, hence the resulting length of the extent
2828  * covering maximum file size must fit into on-disk format containers as
2829  * well. Given that length is always by 1 unit bigger than max unit (because
2830  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2831  *
2832  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2833  */
2834 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2835 {
2836 	loff_t res;
2837 	loff_t upper_limit = MAX_LFS_FILESIZE;
2838 
2839 	BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2840 
2841 	if (!has_huge_files) {
2842 		upper_limit = (1LL << 32) - 1;
2843 
2844 		/* total blocks in file system block size */
2845 		upper_limit >>= (blkbits - 9);
2846 		upper_limit <<= blkbits;
2847 	}
2848 
2849 	/*
2850 	 * 32-bit extent-start container, ee_block. We lower the maxbytes
2851 	 * by one fs block, so ee_len can cover the extent of maximum file
2852 	 * size
2853 	 */
2854 	res = (1LL << 32) - 1;
2855 	res <<= blkbits;
2856 
2857 	/* Sanity check against vm- & vfs- imposed limits */
2858 	if (res > upper_limit)
2859 		res = upper_limit;
2860 
2861 	return res;
2862 }
2863 
2864 /*
2865  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2866  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2867  * We need to be 1 filesystem block less than the 2^48 sector limit.
2868  */
2869 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2870 {
2871 	loff_t res = EXT4_NDIR_BLOCKS;
2872 	int meta_blocks;
2873 	loff_t upper_limit;
2874 	/* This is calculated to be the largest file size for a dense, block
2875 	 * mapped file such that the file's total number of 512-byte sectors,
2876 	 * including data and all indirect blocks, does not exceed (2^48 - 1).
2877 	 *
2878 	 * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2879 	 * number of 512-byte sectors of the file.
2880 	 */
2881 
2882 	if (!has_huge_files) {
2883 		/*
2884 		 * !has_huge_files or implies that the inode i_block field
2885 		 * represents total file blocks in 2^32 512-byte sectors ==
2886 		 * size of vfs inode i_blocks * 8
2887 		 */
2888 		upper_limit = (1LL << 32) - 1;
2889 
2890 		/* total blocks in file system block size */
2891 		upper_limit >>= (bits - 9);
2892 
2893 	} else {
2894 		/*
2895 		 * We use 48 bit ext4_inode i_blocks
2896 		 * With EXT4_HUGE_FILE_FL set the i_blocks
2897 		 * represent total number of blocks in
2898 		 * file system block size
2899 		 */
2900 		upper_limit = (1LL << 48) - 1;
2901 
2902 	}
2903 
2904 	/* indirect blocks */
2905 	meta_blocks = 1;
2906 	/* double indirect blocks */
2907 	meta_blocks += 1 + (1LL << (bits-2));
2908 	/* tripple indirect blocks */
2909 	meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2910 
2911 	upper_limit -= meta_blocks;
2912 	upper_limit <<= bits;
2913 
2914 	res += 1LL << (bits-2);
2915 	res += 1LL << (2*(bits-2));
2916 	res += 1LL << (3*(bits-2));
2917 	res <<= bits;
2918 	if (res > upper_limit)
2919 		res = upper_limit;
2920 
2921 	if (res > MAX_LFS_FILESIZE)
2922 		res = MAX_LFS_FILESIZE;
2923 
2924 	return res;
2925 }
2926 
2927 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2928 				   ext4_fsblk_t logical_sb_block, int nr)
2929 {
2930 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2931 	ext4_group_t bg, first_meta_bg;
2932 	int has_super = 0;
2933 
2934 	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2935 
2936 	if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2937 		return logical_sb_block + nr + 1;
2938 	bg = sbi->s_desc_per_block * nr;
2939 	if (ext4_bg_has_super(sb, bg))
2940 		has_super = 1;
2941 
2942 	/*
2943 	 * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2944 	 * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2945 	 * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2946 	 * compensate.
2947 	 */
2948 	if (sb->s_blocksize == 1024 && nr == 0 &&
2949 	    le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2950 		has_super++;
2951 
2952 	return (has_super + ext4_group_first_block_no(sb, bg));
2953 }
2954 
2955 /**
2956  * ext4_get_stripe_size: Get the stripe size.
2957  * @sbi: In memory super block info
2958  *
2959  * If we have specified it via mount option, then
2960  * use the mount option value. If the value specified at mount time is
2961  * greater than the blocks per group use the super block value.
2962  * If the super block value is greater than blocks per group return 0.
2963  * Allocator needs it be less than blocks per group.
2964  *
2965  */
2966 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2967 {
2968 	unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2969 	unsigned long stripe_width =
2970 			le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2971 	int ret;
2972 
2973 	if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2974 		ret = sbi->s_stripe;
2975 	else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2976 		ret = stripe_width;
2977 	else if (stride && stride <= sbi->s_blocks_per_group)
2978 		ret = stride;
2979 	else
2980 		ret = 0;
2981 
2982 	/*
2983 	 * If the stripe width is 1, this makes no sense and
2984 	 * we set it to 0 to turn off stripe handling code.
2985 	 */
2986 	if (ret <= 1)
2987 		ret = 0;
2988 
2989 	return ret;
2990 }
2991 
2992 /*
2993  * Check whether this filesystem can be mounted based on
2994  * the features present and the RDONLY/RDWR mount requested.
2995  * Returns 1 if this filesystem can be mounted as requested,
2996  * 0 if it cannot be.
2997  */
2998 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2999 {
3000 	if (ext4_has_unknown_ext4_incompat_features(sb)) {
3001 		ext4_msg(sb, KERN_ERR,
3002 			"Couldn't mount because of "
3003 			"unsupported optional features (%x)",
3004 			(le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3005 			~EXT4_FEATURE_INCOMPAT_SUPP));
3006 		return 0;
3007 	}
3008 
3009 #ifndef CONFIG_UNICODE
3010 	if (ext4_has_feature_casefold(sb)) {
3011 		ext4_msg(sb, KERN_ERR,
3012 			 "Filesystem with casefold feature cannot be "
3013 			 "mounted without CONFIG_UNICODE");
3014 		return 0;
3015 	}
3016 #endif
3017 
3018 	if (readonly)
3019 		return 1;
3020 
3021 	if (ext4_has_feature_readonly(sb)) {
3022 		ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3023 		sb->s_flags |= SB_RDONLY;
3024 		return 1;
3025 	}
3026 
3027 	/* Check that feature set is OK for a read-write mount */
3028 	if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3029 		ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3030 			 "unsupported optional features (%x)",
3031 			 (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3032 				~EXT4_FEATURE_RO_COMPAT_SUPP));
3033 		return 0;
3034 	}
3035 	if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3036 		ext4_msg(sb, KERN_ERR,
3037 			 "Can't support bigalloc feature without "
3038 			 "extents feature\n");
3039 		return 0;
3040 	}
3041 
3042 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3043 	if (!readonly && (ext4_has_feature_quota(sb) ||
3044 			  ext4_has_feature_project(sb))) {
3045 		ext4_msg(sb, KERN_ERR,
3046 			 "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3047 		return 0;
3048 	}
3049 #endif  /* CONFIG_QUOTA */
3050 	return 1;
3051 }
3052 
3053 /*
3054  * This function is called once a day if we have errors logged
3055  * on the file system
3056  */
3057 static void print_daily_error_info(struct timer_list *t)
3058 {
3059 	struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3060 	struct super_block *sb = sbi->s_sb;
3061 	struct ext4_super_block *es = sbi->s_es;
3062 
3063 	if (es->s_error_count)
3064 		/* fsck newer than v1.41.13 is needed to clean this condition. */
3065 		ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3066 			 le32_to_cpu(es->s_error_count));
3067 	if (es->s_first_error_time) {
3068 		printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3069 		       sb->s_id,
3070 		       ext4_get_tstamp(es, s_first_error_time),
3071 		       (int) sizeof(es->s_first_error_func),
3072 		       es->s_first_error_func,
3073 		       le32_to_cpu(es->s_first_error_line));
3074 		if (es->s_first_error_ino)
3075 			printk(KERN_CONT ": inode %u",
3076 			       le32_to_cpu(es->s_first_error_ino));
3077 		if (es->s_first_error_block)
3078 			printk(KERN_CONT ": block %llu", (unsigned long long)
3079 			       le64_to_cpu(es->s_first_error_block));
3080 		printk(KERN_CONT "\n");
3081 	}
3082 	if (es->s_last_error_time) {
3083 		printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3084 		       sb->s_id,
3085 		       ext4_get_tstamp(es, s_last_error_time),
3086 		       (int) sizeof(es->s_last_error_func),
3087 		       es->s_last_error_func,
3088 		       le32_to_cpu(es->s_last_error_line));
3089 		if (es->s_last_error_ino)
3090 			printk(KERN_CONT ": inode %u",
3091 			       le32_to_cpu(es->s_last_error_ino));
3092 		if (es->s_last_error_block)
3093 			printk(KERN_CONT ": block %llu", (unsigned long long)
3094 			       le64_to_cpu(es->s_last_error_block));
3095 		printk(KERN_CONT "\n");
3096 	}
3097 	mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3098 }
3099 
3100 /* Find next suitable group and run ext4_init_inode_table */
3101 static int ext4_run_li_request(struct ext4_li_request *elr)
3102 {
3103 	struct ext4_group_desc *gdp = NULL;
3104 	ext4_group_t group, ngroups;
3105 	struct super_block *sb;
3106 	unsigned long timeout = 0;
3107 	int ret = 0;
3108 
3109 	sb = elr->lr_super;
3110 	ngroups = EXT4_SB(sb)->s_groups_count;
3111 
3112 	for (group = elr->lr_next_group; group < ngroups; group++) {
3113 		gdp = ext4_get_group_desc(sb, group, NULL);
3114 		if (!gdp) {
3115 			ret = 1;
3116 			break;
3117 		}
3118 
3119 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3120 			break;
3121 	}
3122 
3123 	if (group >= ngroups)
3124 		ret = 1;
3125 
3126 	if (!ret) {
3127 		timeout = jiffies;
3128 		ret = ext4_init_inode_table(sb, group,
3129 					    elr->lr_timeout ? 0 : 1);
3130 		if (elr->lr_timeout == 0) {
3131 			timeout = (jiffies - timeout) *
3132 				  elr->lr_sbi->s_li_wait_mult;
3133 			elr->lr_timeout = timeout;
3134 		}
3135 		elr->lr_next_sched = jiffies + elr->lr_timeout;
3136 		elr->lr_next_group = group + 1;
3137 	}
3138 	return ret;
3139 }
3140 
3141 /*
3142  * Remove lr_request from the list_request and free the
3143  * request structure. Should be called with li_list_mtx held
3144  */
3145 static void ext4_remove_li_request(struct ext4_li_request *elr)
3146 {
3147 	struct ext4_sb_info *sbi;
3148 
3149 	if (!elr)
3150 		return;
3151 
3152 	sbi = elr->lr_sbi;
3153 
3154 	list_del(&elr->lr_request);
3155 	sbi->s_li_request = NULL;
3156 	kfree(elr);
3157 }
3158 
3159 static void ext4_unregister_li_request(struct super_block *sb)
3160 {
3161 	mutex_lock(&ext4_li_mtx);
3162 	if (!ext4_li_info) {
3163 		mutex_unlock(&ext4_li_mtx);
3164 		return;
3165 	}
3166 
3167 	mutex_lock(&ext4_li_info->li_list_mtx);
3168 	ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3169 	mutex_unlock(&ext4_li_info->li_list_mtx);
3170 	mutex_unlock(&ext4_li_mtx);
3171 }
3172 
3173 static struct task_struct *ext4_lazyinit_task;
3174 
3175 /*
3176  * This is the function where ext4lazyinit thread lives. It walks
3177  * through the request list searching for next scheduled filesystem.
3178  * When such a fs is found, run the lazy initialization request
3179  * (ext4_rn_li_request) and keep track of the time spend in this
3180  * function. Based on that time we compute next schedule time of
3181  * the request. When walking through the list is complete, compute
3182  * next waking time and put itself into sleep.
3183  */
3184 static int ext4_lazyinit_thread(void *arg)
3185 {
3186 	struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3187 	struct list_head *pos, *n;
3188 	struct ext4_li_request *elr;
3189 	unsigned long next_wakeup, cur;
3190 
3191 	BUG_ON(NULL == eli);
3192 
3193 cont_thread:
3194 	while (true) {
3195 		next_wakeup = MAX_JIFFY_OFFSET;
3196 
3197 		mutex_lock(&eli->li_list_mtx);
3198 		if (list_empty(&eli->li_request_list)) {
3199 			mutex_unlock(&eli->li_list_mtx);
3200 			goto exit_thread;
3201 		}
3202 		list_for_each_safe(pos, n, &eli->li_request_list) {
3203 			int err = 0;
3204 			int progress = 0;
3205 			elr = list_entry(pos, struct ext4_li_request,
3206 					 lr_request);
3207 
3208 			if (time_before(jiffies, elr->lr_next_sched)) {
3209 				if (time_before(elr->lr_next_sched, next_wakeup))
3210 					next_wakeup = elr->lr_next_sched;
3211 				continue;
3212 			}
3213 			if (down_read_trylock(&elr->lr_super->s_umount)) {
3214 				if (sb_start_write_trylock(elr->lr_super)) {
3215 					progress = 1;
3216 					/*
3217 					 * We hold sb->s_umount, sb can not
3218 					 * be removed from the list, it is
3219 					 * now safe to drop li_list_mtx
3220 					 */
3221 					mutex_unlock(&eli->li_list_mtx);
3222 					err = ext4_run_li_request(elr);
3223 					sb_end_write(elr->lr_super);
3224 					mutex_lock(&eli->li_list_mtx);
3225 					n = pos->next;
3226 				}
3227 				up_read((&elr->lr_super->s_umount));
3228 			}
3229 			/* error, remove the lazy_init job */
3230 			if (err) {
3231 				ext4_remove_li_request(elr);
3232 				continue;
3233 			}
3234 			if (!progress) {
3235 				elr->lr_next_sched = jiffies +
3236 					(prandom_u32()
3237 					 % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3238 			}
3239 			if (time_before(elr->lr_next_sched, next_wakeup))
3240 				next_wakeup = elr->lr_next_sched;
3241 		}
3242 		mutex_unlock(&eli->li_list_mtx);
3243 
3244 		try_to_freeze();
3245 
3246 		cur = jiffies;
3247 		if ((time_after_eq(cur, next_wakeup)) ||
3248 		    (MAX_JIFFY_OFFSET == next_wakeup)) {
3249 			cond_resched();
3250 			continue;
3251 		}
3252 
3253 		schedule_timeout_interruptible(next_wakeup - cur);
3254 
3255 		if (kthread_should_stop()) {
3256 			ext4_clear_request_list();
3257 			goto exit_thread;
3258 		}
3259 	}
3260 
3261 exit_thread:
3262 	/*
3263 	 * It looks like the request list is empty, but we need
3264 	 * to check it under the li_list_mtx lock, to prevent any
3265 	 * additions into it, and of course we should lock ext4_li_mtx
3266 	 * to atomically free the list and ext4_li_info, because at
3267 	 * this point another ext4 filesystem could be registering
3268 	 * new one.
3269 	 */
3270 	mutex_lock(&ext4_li_mtx);
3271 	mutex_lock(&eli->li_list_mtx);
3272 	if (!list_empty(&eli->li_request_list)) {
3273 		mutex_unlock(&eli->li_list_mtx);
3274 		mutex_unlock(&ext4_li_mtx);
3275 		goto cont_thread;
3276 	}
3277 	mutex_unlock(&eli->li_list_mtx);
3278 	kfree(ext4_li_info);
3279 	ext4_li_info = NULL;
3280 	mutex_unlock(&ext4_li_mtx);
3281 
3282 	return 0;
3283 }
3284 
3285 static void ext4_clear_request_list(void)
3286 {
3287 	struct list_head *pos, *n;
3288 	struct ext4_li_request *elr;
3289 
3290 	mutex_lock(&ext4_li_info->li_list_mtx);
3291 	list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3292 		elr = list_entry(pos, struct ext4_li_request,
3293 				 lr_request);
3294 		ext4_remove_li_request(elr);
3295 	}
3296 	mutex_unlock(&ext4_li_info->li_list_mtx);
3297 }
3298 
3299 static int ext4_run_lazyinit_thread(void)
3300 {
3301 	ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3302 					 ext4_li_info, "ext4lazyinit");
3303 	if (IS_ERR(ext4_lazyinit_task)) {
3304 		int err = PTR_ERR(ext4_lazyinit_task);
3305 		ext4_clear_request_list();
3306 		kfree(ext4_li_info);
3307 		ext4_li_info = NULL;
3308 		printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3309 				 "initialization thread\n",
3310 				 err);
3311 		return err;
3312 	}
3313 	ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3314 	return 0;
3315 }
3316 
3317 /*
3318  * Check whether it make sense to run itable init. thread or not.
3319  * If there is at least one uninitialized inode table, return
3320  * corresponding group number, else the loop goes through all
3321  * groups and return total number of groups.
3322  */
3323 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3324 {
3325 	ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3326 	struct ext4_group_desc *gdp = NULL;
3327 
3328 	if (!ext4_has_group_desc_csum(sb))
3329 		return ngroups;
3330 
3331 	for (group = 0; group < ngroups; group++) {
3332 		gdp = ext4_get_group_desc(sb, group, NULL);
3333 		if (!gdp)
3334 			continue;
3335 
3336 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3337 			break;
3338 	}
3339 
3340 	return group;
3341 }
3342 
3343 static int ext4_li_info_new(void)
3344 {
3345 	struct ext4_lazy_init *eli = NULL;
3346 
3347 	eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3348 	if (!eli)
3349 		return -ENOMEM;
3350 
3351 	INIT_LIST_HEAD(&eli->li_request_list);
3352 	mutex_init(&eli->li_list_mtx);
3353 
3354 	eli->li_state |= EXT4_LAZYINIT_QUIT;
3355 
3356 	ext4_li_info = eli;
3357 
3358 	return 0;
3359 }
3360 
3361 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3362 					    ext4_group_t start)
3363 {
3364 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3365 	struct ext4_li_request *elr;
3366 
3367 	elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3368 	if (!elr)
3369 		return NULL;
3370 
3371 	elr->lr_super = sb;
3372 	elr->lr_sbi = sbi;
3373 	elr->lr_next_group = start;
3374 
3375 	/*
3376 	 * Randomize first schedule time of the request to
3377 	 * spread the inode table initialization requests
3378 	 * better.
3379 	 */
3380 	elr->lr_next_sched = jiffies + (prandom_u32() %
3381 				(EXT4_DEF_LI_MAX_START_DELAY * HZ));
3382 	return elr;
3383 }
3384 
3385 int ext4_register_li_request(struct super_block *sb,
3386 			     ext4_group_t first_not_zeroed)
3387 {
3388 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3389 	struct ext4_li_request *elr = NULL;
3390 	ext4_group_t ngroups = sbi->s_groups_count;
3391 	int ret = 0;
3392 
3393 	mutex_lock(&ext4_li_mtx);
3394 	if (sbi->s_li_request != NULL) {
3395 		/*
3396 		 * Reset timeout so it can be computed again, because
3397 		 * s_li_wait_mult might have changed.
3398 		 */
3399 		sbi->s_li_request->lr_timeout = 0;
3400 		goto out;
3401 	}
3402 
3403 	if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3404 	    !test_opt(sb, INIT_INODE_TABLE))
3405 		goto out;
3406 
3407 	elr = ext4_li_request_new(sb, first_not_zeroed);
3408 	if (!elr) {
3409 		ret = -ENOMEM;
3410 		goto out;
3411 	}
3412 
3413 	if (NULL == ext4_li_info) {
3414 		ret = ext4_li_info_new();
3415 		if (ret)
3416 			goto out;
3417 	}
3418 
3419 	mutex_lock(&ext4_li_info->li_list_mtx);
3420 	list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3421 	mutex_unlock(&ext4_li_info->li_list_mtx);
3422 
3423 	sbi->s_li_request = elr;
3424 	/*
3425 	 * set elr to NULL here since it has been inserted to
3426 	 * the request_list and the removal and free of it is
3427 	 * handled by ext4_clear_request_list from now on.
3428 	 */
3429 	elr = NULL;
3430 
3431 	if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3432 		ret = ext4_run_lazyinit_thread();
3433 		if (ret)
3434 			goto out;
3435 	}
3436 out:
3437 	mutex_unlock(&ext4_li_mtx);
3438 	if (ret)
3439 		kfree(elr);
3440 	return ret;
3441 }
3442 
3443 /*
3444  * We do not need to lock anything since this is called on
3445  * module unload.
3446  */
3447 static void ext4_destroy_lazyinit_thread(void)
3448 {
3449 	/*
3450 	 * If thread exited earlier
3451 	 * there's nothing to be done.
3452 	 */
3453 	if (!ext4_li_info || !ext4_lazyinit_task)
3454 		return;
3455 
3456 	kthread_stop(ext4_lazyinit_task);
3457 }
3458 
3459 static int set_journal_csum_feature_set(struct super_block *sb)
3460 {
3461 	int ret = 1;
3462 	int compat, incompat;
3463 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3464 
3465 	if (ext4_has_metadata_csum(sb)) {
3466 		/* journal checksum v3 */
3467 		compat = 0;
3468 		incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3469 	} else {
3470 		/* journal checksum v1 */
3471 		compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3472 		incompat = 0;
3473 	}
3474 
3475 	jbd2_journal_clear_features(sbi->s_journal,
3476 			JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3477 			JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3478 			JBD2_FEATURE_INCOMPAT_CSUM_V2);
3479 	if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3480 		ret = jbd2_journal_set_features(sbi->s_journal,
3481 				compat, 0,
3482 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3483 				incompat);
3484 	} else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3485 		ret = jbd2_journal_set_features(sbi->s_journal,
3486 				compat, 0,
3487 				incompat);
3488 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3489 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3490 	} else {
3491 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3492 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3493 	}
3494 
3495 	return ret;
3496 }
3497 
3498 /*
3499  * Note: calculating the overhead so we can be compatible with
3500  * historical BSD practice is quite difficult in the face of
3501  * clusters/bigalloc.  This is because multiple metadata blocks from
3502  * different block group can end up in the same allocation cluster.
3503  * Calculating the exact overhead in the face of clustered allocation
3504  * requires either O(all block bitmaps) in memory or O(number of block
3505  * groups**2) in time.  We will still calculate the superblock for
3506  * older file systems --- and if we come across with a bigalloc file
3507  * system with zero in s_overhead_clusters the estimate will be close to
3508  * correct especially for very large cluster sizes --- but for newer
3509  * file systems, it's better to calculate this figure once at mkfs
3510  * time, and store it in the superblock.  If the superblock value is
3511  * present (even for non-bigalloc file systems), we will use it.
3512  */
3513 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3514 			  char *buf)
3515 {
3516 	struct ext4_sb_info	*sbi = EXT4_SB(sb);
3517 	struct ext4_group_desc	*gdp;
3518 	ext4_fsblk_t		first_block, last_block, b;
3519 	ext4_group_t		i, ngroups = ext4_get_groups_count(sb);
3520 	int			s, j, count = 0;
3521 
3522 	if (!ext4_has_feature_bigalloc(sb))
3523 		return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3524 			sbi->s_itb_per_group + 2);
3525 
3526 	first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3527 		(grp * EXT4_BLOCKS_PER_GROUP(sb));
3528 	last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3529 	for (i = 0; i < ngroups; i++) {
3530 		gdp = ext4_get_group_desc(sb, i, NULL);
3531 		b = ext4_block_bitmap(sb, gdp);
3532 		if (b >= first_block && b <= last_block) {
3533 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3534 			count++;
3535 		}
3536 		b = ext4_inode_bitmap(sb, gdp);
3537 		if (b >= first_block && b <= last_block) {
3538 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3539 			count++;
3540 		}
3541 		b = ext4_inode_table(sb, gdp);
3542 		if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3543 			for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3544 				int c = EXT4_B2C(sbi, b - first_block);
3545 				ext4_set_bit(c, buf);
3546 				count++;
3547 			}
3548 		if (i != grp)
3549 			continue;
3550 		s = 0;
3551 		if (ext4_bg_has_super(sb, grp)) {
3552 			ext4_set_bit(s++, buf);
3553 			count++;
3554 		}
3555 		j = ext4_bg_num_gdb(sb, grp);
3556 		if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3557 			ext4_error(sb, "Invalid number of block group "
3558 				   "descriptor blocks: %d", j);
3559 			j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3560 		}
3561 		count += j;
3562 		for (; j > 0; j--)
3563 			ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3564 	}
3565 	if (!count)
3566 		return 0;
3567 	return EXT4_CLUSTERS_PER_GROUP(sb) -
3568 		ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3569 }
3570 
3571 /*
3572  * Compute the overhead and stash it in sbi->s_overhead
3573  */
3574 int ext4_calculate_overhead(struct super_block *sb)
3575 {
3576 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3577 	struct ext4_super_block *es = sbi->s_es;
3578 	struct inode *j_inode;
3579 	unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3580 	ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3581 	ext4_fsblk_t overhead = 0;
3582 	char *buf = (char *) get_zeroed_page(GFP_NOFS);
3583 
3584 	if (!buf)
3585 		return -ENOMEM;
3586 
3587 	/*
3588 	 * Compute the overhead (FS structures).  This is constant
3589 	 * for a given filesystem unless the number of block groups
3590 	 * changes so we cache the previous value until it does.
3591 	 */
3592 
3593 	/*
3594 	 * All of the blocks before first_data_block are overhead
3595 	 */
3596 	overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3597 
3598 	/*
3599 	 * Add the overhead found in each block group
3600 	 */
3601 	for (i = 0; i < ngroups; i++) {
3602 		int blks;
3603 
3604 		blks = count_overhead(sb, i, buf);
3605 		overhead += blks;
3606 		if (blks)
3607 			memset(buf, 0, PAGE_SIZE);
3608 		cond_resched();
3609 	}
3610 
3611 	/*
3612 	 * Add the internal journal blocks whether the journal has been
3613 	 * loaded or not
3614 	 */
3615 	if (sbi->s_journal && !sbi->journal_bdev)
3616 		overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3617 	else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3618 		/* j_inum for internal journal is non-zero */
3619 		j_inode = ext4_get_journal_inode(sb, j_inum);
3620 		if (j_inode) {
3621 			j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3622 			overhead += EXT4_NUM_B2C(sbi, j_blocks);
3623 			iput(j_inode);
3624 		} else {
3625 			ext4_msg(sb, KERN_ERR, "can't get journal size");
3626 		}
3627 	}
3628 	sbi->s_overhead = overhead;
3629 	smp_wmb();
3630 	free_page((unsigned long) buf);
3631 	return 0;
3632 }
3633 
3634 static void ext4_set_resv_clusters(struct super_block *sb)
3635 {
3636 	ext4_fsblk_t resv_clusters;
3637 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3638 
3639 	/*
3640 	 * There's no need to reserve anything when we aren't using extents.
3641 	 * The space estimates are exact, there are no unwritten extents,
3642 	 * hole punching doesn't need new metadata... This is needed especially
3643 	 * to keep ext2/3 backward compatibility.
3644 	 */
3645 	if (!ext4_has_feature_extents(sb))
3646 		return;
3647 	/*
3648 	 * By default we reserve 2% or 4096 clusters, whichever is smaller.
3649 	 * This should cover the situations where we can not afford to run
3650 	 * out of space like for example punch hole, or converting
3651 	 * unwritten extents in delalloc path. In most cases such
3652 	 * allocation would require 1, or 2 blocks, higher numbers are
3653 	 * very rare.
3654 	 */
3655 	resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3656 			 sbi->s_cluster_bits);
3657 
3658 	do_div(resv_clusters, 50);
3659 	resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3660 
3661 	atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3662 }
3663 
3664 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3665 {
3666 	struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3667 	char *orig_data = kstrdup(data, GFP_KERNEL);
3668 	struct buffer_head *bh, **group_desc;
3669 	struct ext4_super_block *es = NULL;
3670 	struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3671 	struct flex_groups **flex_groups;
3672 	ext4_fsblk_t block;
3673 	ext4_fsblk_t sb_block = get_sb_block(&data);
3674 	ext4_fsblk_t logical_sb_block;
3675 	unsigned long offset = 0;
3676 	unsigned long journal_devnum = 0;
3677 	unsigned long def_mount_opts;
3678 	struct inode *root;
3679 	const char *descr;
3680 	int ret = -ENOMEM;
3681 	int blocksize, clustersize;
3682 	unsigned int db_count;
3683 	unsigned int i;
3684 	int needs_recovery, has_huge_files, has_bigalloc;
3685 	__u64 blocks_count;
3686 	int err = 0;
3687 	unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3688 	ext4_group_t first_not_zeroed;
3689 
3690 	if ((data && !orig_data) || !sbi)
3691 		goto out_free_base;
3692 
3693 	sbi->s_daxdev = dax_dev;
3694 	sbi->s_blockgroup_lock =
3695 		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3696 	if (!sbi->s_blockgroup_lock)
3697 		goto out_free_base;
3698 
3699 	sb->s_fs_info = sbi;
3700 	sbi->s_sb = sb;
3701 	sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3702 	sbi->s_sb_block = sb_block;
3703 	if (sb->s_bdev->bd_part)
3704 		sbi->s_sectors_written_start =
3705 			part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3706 
3707 	/* Cleanup superblock name */
3708 	strreplace(sb->s_id, '/', '!');
3709 
3710 	/* -EINVAL is default */
3711 	ret = -EINVAL;
3712 	blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3713 	if (!blocksize) {
3714 		ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3715 		goto out_fail;
3716 	}
3717 
3718 	/*
3719 	 * The ext4 superblock will not be buffer aligned for other than 1kB
3720 	 * block sizes.  We need to calculate the offset from buffer start.
3721 	 */
3722 	if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3723 		logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3724 		offset = do_div(logical_sb_block, blocksize);
3725 	} else {
3726 		logical_sb_block = sb_block;
3727 	}
3728 
3729 	if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3730 		ext4_msg(sb, KERN_ERR, "unable to read superblock");
3731 		goto out_fail;
3732 	}
3733 	/*
3734 	 * Note: s_es must be initialized as soon as possible because
3735 	 *       some ext4 macro-instructions depend on its value
3736 	 */
3737 	es = (struct ext4_super_block *) (bh->b_data + offset);
3738 	sbi->s_es = es;
3739 	sb->s_magic = le16_to_cpu(es->s_magic);
3740 	if (sb->s_magic != EXT4_SUPER_MAGIC)
3741 		goto cantfind_ext4;
3742 	sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3743 
3744 	/* Warn if metadata_csum and gdt_csum are both set. */
3745 	if (ext4_has_feature_metadata_csum(sb) &&
3746 	    ext4_has_feature_gdt_csum(sb))
3747 		ext4_warning(sb, "metadata_csum and uninit_bg are "
3748 			     "redundant flags; please run fsck.");
3749 
3750 	/* Check for a known checksum algorithm */
3751 	if (!ext4_verify_csum_type(sb, es)) {
3752 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3753 			 "unknown checksum algorithm.");
3754 		silent = 1;
3755 		goto cantfind_ext4;
3756 	}
3757 
3758 	/* Load the checksum driver */
3759 	sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3760 	if (IS_ERR(sbi->s_chksum_driver)) {
3761 		ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3762 		ret = PTR_ERR(sbi->s_chksum_driver);
3763 		sbi->s_chksum_driver = NULL;
3764 		goto failed_mount;
3765 	}
3766 
3767 	/* Check superblock checksum */
3768 	if (!ext4_superblock_csum_verify(sb, es)) {
3769 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3770 			 "invalid superblock checksum.  Run e2fsck?");
3771 		silent = 1;
3772 		ret = -EFSBADCRC;
3773 		goto cantfind_ext4;
3774 	}
3775 
3776 	/* Precompute checksum seed for all metadata */
3777 	if (ext4_has_feature_csum_seed(sb))
3778 		sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3779 	else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3780 		sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3781 					       sizeof(es->s_uuid));
3782 
3783 	/* Set defaults before we parse the mount options */
3784 	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3785 	set_opt(sb, INIT_INODE_TABLE);
3786 	if (def_mount_opts & EXT4_DEFM_DEBUG)
3787 		set_opt(sb, DEBUG);
3788 	if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3789 		set_opt(sb, GRPID);
3790 	if (def_mount_opts & EXT4_DEFM_UID16)
3791 		set_opt(sb, NO_UID32);
3792 	/* xattr user namespace & acls are now defaulted on */
3793 	set_opt(sb, XATTR_USER);
3794 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3795 	set_opt(sb, POSIX_ACL);
3796 #endif
3797 	/* don't forget to enable journal_csum when metadata_csum is enabled. */
3798 	if (ext4_has_metadata_csum(sb))
3799 		set_opt(sb, JOURNAL_CHECKSUM);
3800 
3801 	if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3802 		set_opt(sb, JOURNAL_DATA);
3803 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3804 		set_opt(sb, ORDERED_DATA);
3805 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3806 		set_opt(sb, WRITEBACK_DATA);
3807 
3808 	if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3809 		set_opt(sb, ERRORS_PANIC);
3810 	else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3811 		set_opt(sb, ERRORS_CONT);
3812 	else
3813 		set_opt(sb, ERRORS_RO);
3814 	/* block_validity enabled by default; disable with noblock_validity */
3815 	set_opt(sb, BLOCK_VALIDITY);
3816 	if (def_mount_opts & EXT4_DEFM_DISCARD)
3817 		set_opt(sb, DISCARD);
3818 
3819 	sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3820 	sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3821 	sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3822 	sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3823 	sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3824 
3825 	if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3826 		set_opt(sb, BARRIER);
3827 
3828 	/*
3829 	 * enable delayed allocation by default
3830 	 * Use -o nodelalloc to turn it off
3831 	 */
3832 	if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3833 	    ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3834 		set_opt(sb, DELALLOC);
3835 
3836 	/*
3837 	 * set default s_li_wait_mult for lazyinit, for the case there is
3838 	 * no mount option specified.
3839 	 */
3840 	sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3841 
3842 	blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3843 
3844 	if (blocksize == PAGE_SIZE)
3845 		set_opt(sb, DIOREAD_NOLOCK);
3846 
3847 	if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3848 	    blocksize > EXT4_MAX_BLOCK_SIZE) {
3849 		ext4_msg(sb, KERN_ERR,
3850 		       "Unsupported filesystem blocksize %d (%d log_block_size)",
3851 			 blocksize, le32_to_cpu(es->s_log_block_size));
3852 		goto failed_mount;
3853 	}
3854 
3855 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3856 		sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3857 		sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3858 	} else {
3859 		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3860 		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3861 		if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3862 			ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3863 				 sbi->s_first_ino);
3864 			goto failed_mount;
3865 		}
3866 		if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3867 		    (!is_power_of_2(sbi->s_inode_size)) ||
3868 		    (sbi->s_inode_size > blocksize)) {
3869 			ext4_msg(sb, KERN_ERR,
3870 			       "unsupported inode size: %d",
3871 			       sbi->s_inode_size);
3872 			ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
3873 			goto failed_mount;
3874 		}
3875 		/*
3876 		 * i_atime_extra is the last extra field available for
3877 		 * [acm]times in struct ext4_inode. Checking for that
3878 		 * field should suffice to ensure we have extra space
3879 		 * for all three.
3880 		 */
3881 		if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
3882 			sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
3883 			sb->s_time_gran = 1;
3884 			sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
3885 		} else {
3886 			sb->s_time_gran = NSEC_PER_SEC;
3887 			sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
3888 		}
3889 		sb->s_time_min = EXT4_TIMESTAMP_MIN;
3890 	}
3891 	if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3892 		sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3893 			EXT4_GOOD_OLD_INODE_SIZE;
3894 		if (ext4_has_feature_extra_isize(sb)) {
3895 			unsigned v, max = (sbi->s_inode_size -
3896 					   EXT4_GOOD_OLD_INODE_SIZE);
3897 
3898 			v = le16_to_cpu(es->s_want_extra_isize);
3899 			if (v > max) {
3900 				ext4_msg(sb, KERN_ERR,
3901 					 "bad s_want_extra_isize: %d", v);
3902 				goto failed_mount;
3903 			}
3904 			if (sbi->s_want_extra_isize < v)
3905 				sbi->s_want_extra_isize = v;
3906 
3907 			v = le16_to_cpu(es->s_min_extra_isize);
3908 			if (v > max) {
3909 				ext4_msg(sb, KERN_ERR,
3910 					 "bad s_min_extra_isize: %d", v);
3911 				goto failed_mount;
3912 			}
3913 			if (sbi->s_want_extra_isize < v)
3914 				sbi->s_want_extra_isize = v;
3915 		}
3916 	}
3917 
3918 	if (sbi->s_es->s_mount_opts[0]) {
3919 		char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3920 					      sizeof(sbi->s_es->s_mount_opts),
3921 					      GFP_KERNEL);
3922 		if (!s_mount_opts)
3923 			goto failed_mount;
3924 		if (!parse_options(s_mount_opts, sb, &journal_devnum,
3925 				   &journal_ioprio, 0)) {
3926 			ext4_msg(sb, KERN_WARNING,
3927 				 "failed to parse options in superblock: %s",
3928 				 s_mount_opts);
3929 		}
3930 		kfree(s_mount_opts);
3931 	}
3932 	sbi->s_def_mount_opt = sbi->s_mount_opt;
3933 	if (!parse_options((char *) data, sb, &journal_devnum,
3934 			   &journal_ioprio, 0))
3935 		goto failed_mount;
3936 
3937 #ifdef CONFIG_UNICODE
3938 	if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
3939 		const struct ext4_sb_encodings *encoding_info;
3940 		struct unicode_map *encoding;
3941 		__u16 encoding_flags;
3942 
3943 		if (ext4_has_feature_encrypt(sb)) {
3944 			ext4_msg(sb, KERN_ERR,
3945 				 "Can't mount with encoding and encryption");
3946 			goto failed_mount;
3947 		}
3948 
3949 		if (ext4_sb_read_encoding(es, &encoding_info,
3950 					  &encoding_flags)) {
3951 			ext4_msg(sb, KERN_ERR,
3952 				 "Encoding requested by superblock is unknown");
3953 			goto failed_mount;
3954 		}
3955 
3956 		encoding = utf8_load(encoding_info->version);
3957 		if (IS_ERR(encoding)) {
3958 			ext4_msg(sb, KERN_ERR,
3959 				 "can't mount with superblock charset: %s-%s "
3960 				 "not supported by the kernel. flags: 0x%x.",
3961 				 encoding_info->name, encoding_info->version,
3962 				 encoding_flags);
3963 			goto failed_mount;
3964 		}
3965 		ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
3966 			 "%s-%s with flags 0x%hx", encoding_info->name,
3967 			 encoding_info->version?:"\b", encoding_flags);
3968 
3969 		sbi->s_encoding = encoding;
3970 		sbi->s_encoding_flags = encoding_flags;
3971 	}
3972 #endif
3973 
3974 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3975 		printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!\n");
3976 		clear_opt(sb, DIOREAD_NOLOCK);
3977 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3978 			ext4_msg(sb, KERN_ERR, "can't mount with "
3979 				 "both data=journal and delalloc");
3980 			goto failed_mount;
3981 		}
3982 		if (test_opt(sb, DIOREAD_NOLOCK)) {
3983 			ext4_msg(sb, KERN_ERR, "can't mount with "
3984 				 "both data=journal and dioread_nolock");
3985 			goto failed_mount;
3986 		}
3987 		if (test_opt(sb, DAX)) {
3988 			ext4_msg(sb, KERN_ERR, "can't mount with "
3989 				 "both data=journal and dax");
3990 			goto failed_mount;
3991 		}
3992 		if (ext4_has_feature_encrypt(sb)) {
3993 			ext4_msg(sb, KERN_WARNING,
3994 				 "encrypted files will use data=ordered "
3995 				 "instead of data journaling mode");
3996 		}
3997 		if (test_opt(sb, DELALLOC))
3998 			clear_opt(sb, DELALLOC);
3999 	} else {
4000 		sb->s_iflags |= SB_I_CGROUPWB;
4001 	}
4002 
4003 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4004 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4005 
4006 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4007 	    (ext4_has_compat_features(sb) ||
4008 	     ext4_has_ro_compat_features(sb) ||
4009 	     ext4_has_incompat_features(sb)))
4010 		ext4_msg(sb, KERN_WARNING,
4011 		       "feature flags set on rev 0 fs, "
4012 		       "running e2fsck is recommended");
4013 
4014 	if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4015 		set_opt2(sb, HURD_COMPAT);
4016 		if (ext4_has_feature_64bit(sb)) {
4017 			ext4_msg(sb, KERN_ERR,
4018 				 "The Hurd can't support 64-bit file systems");
4019 			goto failed_mount;
4020 		}
4021 
4022 		/*
4023 		 * ea_inode feature uses l_i_version field which is not
4024 		 * available in HURD_COMPAT mode.
4025 		 */
4026 		if (ext4_has_feature_ea_inode(sb)) {
4027 			ext4_msg(sb, KERN_ERR,
4028 				 "ea_inode feature is not supported for Hurd");
4029 			goto failed_mount;
4030 		}
4031 	}
4032 
4033 	if (IS_EXT2_SB(sb)) {
4034 		if (ext2_feature_set_ok(sb))
4035 			ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4036 				 "using the ext4 subsystem");
4037 		else {
4038 			/*
4039 			 * If we're probing be silent, if this looks like
4040 			 * it's actually an ext[34] filesystem.
4041 			 */
4042 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4043 				goto failed_mount;
4044 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4045 				 "to feature incompatibilities");
4046 			goto failed_mount;
4047 		}
4048 	}
4049 
4050 	if (IS_EXT3_SB(sb)) {
4051 		if (ext3_feature_set_ok(sb))
4052 			ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4053 				 "using the ext4 subsystem");
4054 		else {
4055 			/*
4056 			 * If we're probing be silent, if this looks like
4057 			 * it's actually an ext4 filesystem.
4058 			 */
4059 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4060 				goto failed_mount;
4061 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4062 				 "to feature incompatibilities");
4063 			goto failed_mount;
4064 		}
4065 	}
4066 
4067 	/*
4068 	 * Check feature flags regardless of the revision level, since we
4069 	 * previously didn't change the revision level when setting the flags,
4070 	 * so there is a chance incompat flags are set on a rev 0 filesystem.
4071 	 */
4072 	if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4073 		goto failed_mount;
4074 
4075 	if (le32_to_cpu(es->s_log_block_size) >
4076 	    (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4077 		ext4_msg(sb, KERN_ERR,
4078 			 "Invalid log block size: %u",
4079 			 le32_to_cpu(es->s_log_block_size));
4080 		goto failed_mount;
4081 	}
4082 	if (le32_to_cpu(es->s_log_cluster_size) >
4083 	    (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4084 		ext4_msg(sb, KERN_ERR,
4085 			 "Invalid log cluster size: %u",
4086 			 le32_to_cpu(es->s_log_cluster_size));
4087 		goto failed_mount;
4088 	}
4089 
4090 	if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4091 		ext4_msg(sb, KERN_ERR,
4092 			 "Number of reserved GDT blocks insanely large: %d",
4093 			 le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4094 		goto failed_mount;
4095 	}
4096 
4097 	if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
4098 		if (ext4_has_feature_inline_data(sb)) {
4099 			ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4100 					" that may contain inline data");
4101 			goto failed_mount;
4102 		}
4103 		if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
4104 			ext4_msg(sb, KERN_ERR,
4105 				"DAX unsupported by block device.");
4106 			goto failed_mount;
4107 		}
4108 	}
4109 
4110 	if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4111 		ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4112 			 es->s_encryption_level);
4113 		goto failed_mount;
4114 	}
4115 
4116 	if (sb->s_blocksize != blocksize) {
4117 		/* Validate the filesystem blocksize */
4118 		if (!sb_set_blocksize(sb, blocksize)) {
4119 			ext4_msg(sb, KERN_ERR, "bad block size %d",
4120 					blocksize);
4121 			goto failed_mount;
4122 		}
4123 
4124 		brelse(bh);
4125 		logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4126 		offset = do_div(logical_sb_block, blocksize);
4127 		bh = sb_bread_unmovable(sb, logical_sb_block);
4128 		if (!bh) {
4129 			ext4_msg(sb, KERN_ERR,
4130 			       "Can't read superblock on 2nd try");
4131 			goto failed_mount;
4132 		}
4133 		es = (struct ext4_super_block *)(bh->b_data + offset);
4134 		sbi->s_es = es;
4135 		if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4136 			ext4_msg(sb, KERN_ERR,
4137 			       "Magic mismatch, very weird!");
4138 			goto failed_mount;
4139 		}
4140 	}
4141 
4142 	has_huge_files = ext4_has_feature_huge_file(sb);
4143 	sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4144 						      has_huge_files);
4145 	sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4146 
4147 	sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4148 	if (ext4_has_feature_64bit(sb)) {
4149 		if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4150 		    sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4151 		    !is_power_of_2(sbi->s_desc_size)) {
4152 			ext4_msg(sb, KERN_ERR,
4153 			       "unsupported descriptor size %lu",
4154 			       sbi->s_desc_size);
4155 			goto failed_mount;
4156 		}
4157 	} else
4158 		sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4159 
4160 	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4161 	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4162 
4163 	sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4164 	if (sbi->s_inodes_per_block == 0)
4165 		goto cantfind_ext4;
4166 	if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4167 	    sbi->s_inodes_per_group > blocksize * 8) {
4168 		ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4169 			 sbi->s_inodes_per_group);
4170 		goto failed_mount;
4171 	}
4172 	sbi->s_itb_per_group = sbi->s_inodes_per_group /
4173 					sbi->s_inodes_per_block;
4174 	sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4175 	sbi->s_sbh = bh;
4176 	sbi->s_mount_state = le16_to_cpu(es->s_state);
4177 	sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4178 	sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4179 
4180 	for (i = 0; i < 4; i++)
4181 		sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4182 	sbi->s_def_hash_version = es->s_def_hash_version;
4183 	if (ext4_has_feature_dir_index(sb)) {
4184 		i = le32_to_cpu(es->s_flags);
4185 		if (i & EXT2_FLAGS_UNSIGNED_HASH)
4186 			sbi->s_hash_unsigned = 3;
4187 		else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4188 #ifdef __CHAR_UNSIGNED__
4189 			if (!sb_rdonly(sb))
4190 				es->s_flags |=
4191 					cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4192 			sbi->s_hash_unsigned = 3;
4193 #else
4194 			if (!sb_rdonly(sb))
4195 				es->s_flags |=
4196 					cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4197 #endif
4198 		}
4199 	}
4200 
4201 	/* Handle clustersize */
4202 	clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4203 	has_bigalloc = ext4_has_feature_bigalloc(sb);
4204 	if (has_bigalloc) {
4205 		if (clustersize < blocksize) {
4206 			ext4_msg(sb, KERN_ERR,
4207 				 "cluster size (%d) smaller than "
4208 				 "block size (%d)", clustersize, blocksize);
4209 			goto failed_mount;
4210 		}
4211 		sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4212 			le32_to_cpu(es->s_log_block_size);
4213 		sbi->s_clusters_per_group =
4214 			le32_to_cpu(es->s_clusters_per_group);
4215 		if (sbi->s_clusters_per_group > blocksize * 8) {
4216 			ext4_msg(sb, KERN_ERR,
4217 				 "#clusters per group too big: %lu",
4218 				 sbi->s_clusters_per_group);
4219 			goto failed_mount;
4220 		}
4221 		if (sbi->s_blocks_per_group !=
4222 		    (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4223 			ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4224 				 "clusters per group (%lu) inconsistent",
4225 				 sbi->s_blocks_per_group,
4226 				 sbi->s_clusters_per_group);
4227 			goto failed_mount;
4228 		}
4229 	} else {
4230 		if (clustersize != blocksize) {
4231 			ext4_msg(sb, KERN_ERR,
4232 				 "fragment/cluster size (%d) != "
4233 				 "block size (%d)", clustersize, blocksize);
4234 			goto failed_mount;
4235 		}
4236 		if (sbi->s_blocks_per_group > blocksize * 8) {
4237 			ext4_msg(sb, KERN_ERR,
4238 				 "#blocks per group too big: %lu",
4239 				 sbi->s_blocks_per_group);
4240 			goto failed_mount;
4241 		}
4242 		sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4243 		sbi->s_cluster_bits = 0;
4244 	}
4245 	sbi->s_cluster_ratio = clustersize / blocksize;
4246 
4247 	/* Do we have standard group size of clustersize * 8 blocks ? */
4248 	if (sbi->s_blocks_per_group == clustersize << 3)
4249 		set_opt2(sb, STD_GROUP_SIZE);
4250 
4251 	/*
4252 	 * Test whether we have more sectors than will fit in sector_t,
4253 	 * and whether the max offset is addressable by the page cache.
4254 	 */
4255 	err = generic_check_addressable(sb->s_blocksize_bits,
4256 					ext4_blocks_count(es));
4257 	if (err) {
4258 		ext4_msg(sb, KERN_ERR, "filesystem"
4259 			 " too large to mount safely on this system");
4260 		goto failed_mount;
4261 	}
4262 
4263 	if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4264 		goto cantfind_ext4;
4265 
4266 	/* check blocks count against device size */
4267 	blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4268 	if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4269 		ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4270 		       "exceeds size of device (%llu blocks)",
4271 		       ext4_blocks_count(es), blocks_count);
4272 		goto failed_mount;
4273 	}
4274 
4275 	/*
4276 	 * It makes no sense for the first data block to be beyond the end
4277 	 * of the filesystem.
4278 	 */
4279 	if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4280 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4281 			 "block %u is beyond end of filesystem (%llu)",
4282 			 le32_to_cpu(es->s_first_data_block),
4283 			 ext4_blocks_count(es));
4284 		goto failed_mount;
4285 	}
4286 	if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4287 	    (sbi->s_cluster_ratio == 1)) {
4288 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4289 			 "block is 0 with a 1k block and cluster size");
4290 		goto failed_mount;
4291 	}
4292 
4293 	blocks_count = (ext4_blocks_count(es) -
4294 			le32_to_cpu(es->s_first_data_block) +
4295 			EXT4_BLOCKS_PER_GROUP(sb) - 1);
4296 	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4297 	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4298 		ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4299 		       "(block count %llu, first data block %u, "
4300 		       "blocks per group %lu)", blocks_count,
4301 		       ext4_blocks_count(es),
4302 		       le32_to_cpu(es->s_first_data_block),
4303 		       EXT4_BLOCKS_PER_GROUP(sb));
4304 		goto failed_mount;
4305 	}
4306 	sbi->s_groups_count = blocks_count;
4307 	sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4308 			(EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4309 	if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4310 	    le32_to_cpu(es->s_inodes_count)) {
4311 		ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4312 			 le32_to_cpu(es->s_inodes_count),
4313 			 ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4314 		ret = -EINVAL;
4315 		goto failed_mount;
4316 	}
4317 	db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4318 		   EXT4_DESC_PER_BLOCK(sb);
4319 	if (ext4_has_feature_meta_bg(sb)) {
4320 		if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4321 			ext4_msg(sb, KERN_WARNING,
4322 				 "first meta block group too large: %u "
4323 				 "(group descriptor block count %u)",
4324 				 le32_to_cpu(es->s_first_meta_bg), db_count);
4325 			goto failed_mount;
4326 		}
4327 	}
4328 	rcu_assign_pointer(sbi->s_group_desc,
4329 			   kvmalloc_array(db_count,
4330 					  sizeof(struct buffer_head *),
4331 					  GFP_KERNEL));
4332 	if (sbi->s_group_desc == NULL) {
4333 		ext4_msg(sb, KERN_ERR, "not enough memory");
4334 		ret = -ENOMEM;
4335 		goto failed_mount;
4336 	}
4337 
4338 	bgl_lock_init(sbi->s_blockgroup_lock);
4339 
4340 	/* Pre-read the descriptors into the buffer cache */
4341 	for (i = 0; i < db_count; i++) {
4342 		block = descriptor_loc(sb, logical_sb_block, i);
4343 		sb_breadahead(sb, block);
4344 	}
4345 
4346 	for (i = 0; i < db_count; i++) {
4347 		struct buffer_head *bh;
4348 
4349 		block = descriptor_loc(sb, logical_sb_block, i);
4350 		bh = sb_bread_unmovable(sb, block);
4351 		if (!bh) {
4352 			ext4_msg(sb, KERN_ERR,
4353 			       "can't read group descriptor %d", i);
4354 			db_count = i;
4355 			goto failed_mount2;
4356 		}
4357 		rcu_read_lock();
4358 		rcu_dereference(sbi->s_group_desc)[i] = bh;
4359 		rcu_read_unlock();
4360 	}
4361 	sbi->s_gdb_count = db_count;
4362 	if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4363 		ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4364 		ret = -EFSCORRUPTED;
4365 		goto failed_mount2;
4366 	}
4367 
4368 	timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4369 
4370 	/* Register extent status tree shrinker */
4371 	if (ext4_es_register_shrinker(sbi))
4372 		goto failed_mount3;
4373 
4374 	sbi->s_stripe = ext4_get_stripe_size(sbi);
4375 	sbi->s_extent_max_zeroout_kb = 32;
4376 
4377 	/*
4378 	 * set up enough so that it can read an inode
4379 	 */
4380 	sb->s_op = &ext4_sops;
4381 	sb->s_export_op = &ext4_export_ops;
4382 	sb->s_xattr = ext4_xattr_handlers;
4383 #ifdef CONFIG_FS_ENCRYPTION
4384 	sb->s_cop = &ext4_cryptops;
4385 #endif
4386 #ifdef CONFIG_FS_VERITY
4387 	sb->s_vop = &ext4_verityops;
4388 #endif
4389 #ifdef CONFIG_QUOTA
4390 	sb->dq_op = &ext4_quota_operations;
4391 	if (ext4_has_feature_quota(sb))
4392 		sb->s_qcop = &dquot_quotactl_sysfile_ops;
4393 	else
4394 		sb->s_qcop = &ext4_qctl_operations;
4395 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4396 #endif
4397 	memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4398 
4399 	INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4400 	mutex_init(&sbi->s_orphan_lock);
4401 
4402 	sb->s_root = NULL;
4403 
4404 	needs_recovery = (es->s_last_orphan != 0 ||
4405 			  ext4_has_feature_journal_needs_recovery(sb));
4406 
4407 	if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4408 		if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4409 			goto failed_mount3a;
4410 
4411 	/*
4412 	 * The first inode we look at is the journal inode.  Don't try
4413 	 * root first: it may be modified in the journal!
4414 	 */
4415 	if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4416 		err = ext4_load_journal(sb, es, journal_devnum);
4417 		if (err)
4418 			goto failed_mount3a;
4419 	} else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4420 		   ext4_has_feature_journal_needs_recovery(sb)) {
4421 		ext4_msg(sb, KERN_ERR, "required journal recovery "
4422 		       "suppressed and not mounted read-only");
4423 		goto failed_mount_wq;
4424 	} else {
4425 		/* Nojournal mode, all journal mount options are illegal */
4426 		if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4427 			ext4_msg(sb, KERN_ERR, "can't mount with "
4428 				 "journal_checksum, fs mounted w/o journal");
4429 			goto failed_mount_wq;
4430 		}
4431 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4432 			ext4_msg(sb, KERN_ERR, "can't mount with "
4433 				 "journal_async_commit, fs mounted w/o journal");
4434 			goto failed_mount_wq;
4435 		}
4436 		if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4437 			ext4_msg(sb, KERN_ERR, "can't mount with "
4438 				 "commit=%lu, fs mounted w/o journal",
4439 				 sbi->s_commit_interval / HZ);
4440 			goto failed_mount_wq;
4441 		}
4442 		if (EXT4_MOUNT_DATA_FLAGS &
4443 		    (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4444 			ext4_msg(sb, KERN_ERR, "can't mount with "
4445 				 "data=, fs mounted w/o journal");
4446 			goto failed_mount_wq;
4447 		}
4448 		sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4449 		clear_opt(sb, JOURNAL_CHECKSUM);
4450 		clear_opt(sb, DATA_FLAGS);
4451 		sbi->s_journal = NULL;
4452 		needs_recovery = 0;
4453 		goto no_journal;
4454 	}
4455 
4456 	if (ext4_has_feature_64bit(sb) &&
4457 	    !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4458 				       JBD2_FEATURE_INCOMPAT_64BIT)) {
4459 		ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4460 		goto failed_mount_wq;
4461 	}
4462 
4463 	if (!set_journal_csum_feature_set(sb)) {
4464 		ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4465 			 "feature set");
4466 		goto failed_mount_wq;
4467 	}
4468 
4469 	/* We have now updated the journal if required, so we can
4470 	 * validate the data journaling mode. */
4471 	switch (test_opt(sb, DATA_FLAGS)) {
4472 	case 0:
4473 		/* No mode set, assume a default based on the journal
4474 		 * capabilities: ORDERED_DATA if the journal can
4475 		 * cope, else JOURNAL_DATA
4476 		 */
4477 		if (jbd2_journal_check_available_features
4478 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4479 			set_opt(sb, ORDERED_DATA);
4480 			sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4481 		} else {
4482 			set_opt(sb, JOURNAL_DATA);
4483 			sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4484 		}
4485 		break;
4486 
4487 	case EXT4_MOUNT_ORDERED_DATA:
4488 	case EXT4_MOUNT_WRITEBACK_DATA:
4489 		if (!jbd2_journal_check_available_features
4490 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4491 			ext4_msg(sb, KERN_ERR, "Journal does not support "
4492 			       "requested data journaling mode");
4493 			goto failed_mount_wq;
4494 		}
4495 	default:
4496 		break;
4497 	}
4498 
4499 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4500 	    test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4501 		ext4_msg(sb, KERN_ERR, "can't mount with "
4502 			"journal_async_commit in data=ordered mode");
4503 		goto failed_mount_wq;
4504 	}
4505 
4506 	set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4507 
4508 	sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4509 
4510 no_journal:
4511 	if (!test_opt(sb, NO_MBCACHE)) {
4512 		sbi->s_ea_block_cache = ext4_xattr_create_cache();
4513 		if (!sbi->s_ea_block_cache) {
4514 			ext4_msg(sb, KERN_ERR,
4515 				 "Failed to create ea_block_cache");
4516 			goto failed_mount_wq;
4517 		}
4518 
4519 		if (ext4_has_feature_ea_inode(sb)) {
4520 			sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4521 			if (!sbi->s_ea_inode_cache) {
4522 				ext4_msg(sb, KERN_ERR,
4523 					 "Failed to create ea_inode_cache");
4524 				goto failed_mount_wq;
4525 			}
4526 		}
4527 	}
4528 
4529 	if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4530 		ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4531 		goto failed_mount_wq;
4532 	}
4533 
4534 	if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4535 	    !ext4_has_feature_encrypt(sb)) {
4536 		ext4_set_feature_encrypt(sb);
4537 		ext4_commit_super(sb, 1);
4538 	}
4539 
4540 	/*
4541 	 * Get the # of file system overhead blocks from the
4542 	 * superblock if present.
4543 	 */
4544 	if (es->s_overhead_clusters)
4545 		sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4546 	else {
4547 		err = ext4_calculate_overhead(sb);
4548 		if (err)
4549 			goto failed_mount_wq;
4550 	}
4551 
4552 	/*
4553 	 * The maximum number of concurrent works can be high and
4554 	 * concurrency isn't really necessary.  Limit it to 1.
4555 	 */
4556 	EXT4_SB(sb)->rsv_conversion_wq =
4557 		alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4558 	if (!EXT4_SB(sb)->rsv_conversion_wq) {
4559 		printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4560 		ret = -ENOMEM;
4561 		goto failed_mount4;
4562 	}
4563 
4564 	/*
4565 	 * The jbd2_journal_load will have done any necessary log recovery,
4566 	 * so we can safely mount the rest of the filesystem now.
4567 	 */
4568 
4569 	root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4570 	if (IS_ERR(root)) {
4571 		ext4_msg(sb, KERN_ERR, "get root inode failed");
4572 		ret = PTR_ERR(root);
4573 		root = NULL;
4574 		goto failed_mount4;
4575 	}
4576 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4577 		ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4578 		iput(root);
4579 		goto failed_mount4;
4580 	}
4581 
4582 #ifdef CONFIG_UNICODE
4583 	if (sbi->s_encoding)
4584 		sb->s_d_op = &ext4_dentry_ops;
4585 #endif
4586 
4587 	sb->s_root = d_make_root(root);
4588 	if (!sb->s_root) {
4589 		ext4_msg(sb, KERN_ERR, "get root dentry failed");
4590 		ret = -ENOMEM;
4591 		goto failed_mount4;
4592 	}
4593 
4594 	ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4595 	if (ret == -EROFS) {
4596 		sb->s_flags |= SB_RDONLY;
4597 		ret = 0;
4598 	} else if (ret)
4599 		goto failed_mount4a;
4600 
4601 	ext4_set_resv_clusters(sb);
4602 
4603 	err = ext4_setup_system_zone(sb);
4604 	if (err) {
4605 		ext4_msg(sb, KERN_ERR, "failed to initialize system "
4606 			 "zone (%d)", err);
4607 		goto failed_mount4a;
4608 	}
4609 
4610 	ext4_ext_init(sb);
4611 	err = ext4_mb_init(sb);
4612 	if (err) {
4613 		ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4614 			 err);
4615 		goto failed_mount5;
4616 	}
4617 
4618 	block = ext4_count_free_clusters(sb);
4619 	ext4_free_blocks_count_set(sbi->s_es,
4620 				   EXT4_C2B(sbi, block));
4621 	ext4_superblock_csum_set(sb);
4622 	err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4623 				  GFP_KERNEL);
4624 	if (!err) {
4625 		unsigned long freei = ext4_count_free_inodes(sb);
4626 		sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4627 		ext4_superblock_csum_set(sb);
4628 		err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4629 					  GFP_KERNEL);
4630 	}
4631 	if (!err)
4632 		err = percpu_counter_init(&sbi->s_dirs_counter,
4633 					  ext4_count_dirs(sb), GFP_KERNEL);
4634 	if (!err)
4635 		err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4636 					  GFP_KERNEL);
4637 	if (!err)
4638 		err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4639 
4640 	if (err) {
4641 		ext4_msg(sb, KERN_ERR, "insufficient memory");
4642 		goto failed_mount6;
4643 	}
4644 
4645 	if (ext4_has_feature_flex_bg(sb))
4646 		if (!ext4_fill_flex_info(sb)) {
4647 			ext4_msg(sb, KERN_ERR,
4648 			       "unable to initialize "
4649 			       "flex_bg meta info!");
4650 			goto failed_mount6;
4651 		}
4652 
4653 	err = ext4_register_li_request(sb, first_not_zeroed);
4654 	if (err)
4655 		goto failed_mount6;
4656 
4657 	err = ext4_register_sysfs(sb);
4658 	if (err)
4659 		goto failed_mount7;
4660 
4661 #ifdef CONFIG_QUOTA
4662 	/* Enable quota usage during mount. */
4663 	if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4664 		err = ext4_enable_quotas(sb);
4665 		if (err)
4666 			goto failed_mount8;
4667 	}
4668 #endif  /* CONFIG_QUOTA */
4669 
4670 	EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4671 	ext4_orphan_cleanup(sb, es);
4672 	EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4673 	if (needs_recovery) {
4674 		ext4_msg(sb, KERN_INFO, "recovery complete");
4675 		ext4_mark_recovery_complete(sb, es);
4676 	}
4677 	if (EXT4_SB(sb)->s_journal) {
4678 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4679 			descr = " journalled data mode";
4680 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4681 			descr = " ordered data mode";
4682 		else
4683 			descr = " writeback data mode";
4684 	} else
4685 		descr = "out journal";
4686 
4687 	if (test_opt(sb, DISCARD)) {
4688 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
4689 		if (!blk_queue_discard(q))
4690 			ext4_msg(sb, KERN_WARNING,
4691 				 "mounting with \"discard\" option, but "
4692 				 "the device does not support discard");
4693 	}
4694 
4695 	if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4696 		ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4697 			 "Opts: %.*s%s%s", descr,
4698 			 (int) sizeof(sbi->s_es->s_mount_opts),
4699 			 sbi->s_es->s_mount_opts,
4700 			 *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4701 
4702 	if (es->s_error_count)
4703 		mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4704 
4705 	/* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4706 	ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4707 	ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4708 	ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4709 
4710 	kfree(orig_data);
4711 	return 0;
4712 
4713 cantfind_ext4:
4714 	if (!silent)
4715 		ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4716 	goto failed_mount;
4717 
4718 #ifdef CONFIG_QUOTA
4719 failed_mount8:
4720 	ext4_unregister_sysfs(sb);
4721 #endif
4722 failed_mount7:
4723 	ext4_unregister_li_request(sb);
4724 failed_mount6:
4725 	ext4_mb_release(sb);
4726 	rcu_read_lock();
4727 	flex_groups = rcu_dereference(sbi->s_flex_groups);
4728 	if (flex_groups) {
4729 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
4730 			kvfree(flex_groups[i]);
4731 		kvfree(flex_groups);
4732 	}
4733 	rcu_read_unlock();
4734 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
4735 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
4736 	percpu_counter_destroy(&sbi->s_dirs_counter);
4737 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4738 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
4739 failed_mount5:
4740 	ext4_ext_release(sb);
4741 	ext4_release_system_zone(sb);
4742 failed_mount4a:
4743 	dput(sb->s_root);
4744 	sb->s_root = NULL;
4745 failed_mount4:
4746 	ext4_msg(sb, KERN_ERR, "mount failed");
4747 	if (EXT4_SB(sb)->rsv_conversion_wq)
4748 		destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4749 failed_mount_wq:
4750 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4751 	sbi->s_ea_inode_cache = NULL;
4752 
4753 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4754 	sbi->s_ea_block_cache = NULL;
4755 
4756 	if (sbi->s_journal) {
4757 		jbd2_journal_destroy(sbi->s_journal);
4758 		sbi->s_journal = NULL;
4759 	}
4760 failed_mount3a:
4761 	ext4_es_unregister_shrinker(sbi);
4762 failed_mount3:
4763 	del_timer_sync(&sbi->s_err_report);
4764 	if (sbi->s_mmp_tsk)
4765 		kthread_stop(sbi->s_mmp_tsk);
4766 failed_mount2:
4767 	rcu_read_lock();
4768 	group_desc = rcu_dereference(sbi->s_group_desc);
4769 	for (i = 0; i < db_count; i++)
4770 		brelse(group_desc[i]);
4771 	kvfree(group_desc);
4772 	rcu_read_unlock();
4773 failed_mount:
4774 	if (sbi->s_chksum_driver)
4775 		crypto_free_shash(sbi->s_chksum_driver);
4776 
4777 #ifdef CONFIG_UNICODE
4778 	utf8_unload(sbi->s_encoding);
4779 #endif
4780 
4781 #ifdef CONFIG_QUOTA
4782 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
4783 		kfree(get_qf_name(sb, sbi, i));
4784 #endif
4785 	ext4_blkdev_remove(sbi);
4786 	brelse(bh);
4787 out_fail:
4788 	sb->s_fs_info = NULL;
4789 	kfree(sbi->s_blockgroup_lock);
4790 out_free_base:
4791 	kfree(sbi);
4792 	kfree(orig_data);
4793 	fs_put_dax(dax_dev);
4794 	return err ? err : ret;
4795 }
4796 
4797 /*
4798  * Setup any per-fs journal parameters now.  We'll do this both on
4799  * initial mount, once the journal has been initialised but before we've
4800  * done any recovery; and again on any subsequent remount.
4801  */
4802 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4803 {
4804 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4805 
4806 	journal->j_commit_interval = sbi->s_commit_interval;
4807 	journal->j_min_batch_time = sbi->s_min_batch_time;
4808 	journal->j_max_batch_time = sbi->s_max_batch_time;
4809 
4810 	write_lock(&journal->j_state_lock);
4811 	if (test_opt(sb, BARRIER))
4812 		journal->j_flags |= JBD2_BARRIER;
4813 	else
4814 		journal->j_flags &= ~JBD2_BARRIER;
4815 	if (test_opt(sb, DATA_ERR_ABORT))
4816 		journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4817 	else
4818 		journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4819 	write_unlock(&journal->j_state_lock);
4820 }
4821 
4822 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4823 					     unsigned int journal_inum)
4824 {
4825 	struct inode *journal_inode;
4826 
4827 	/*
4828 	 * Test for the existence of a valid inode on disk.  Bad things
4829 	 * happen if we iget() an unused inode, as the subsequent iput()
4830 	 * will try to delete it.
4831 	 */
4832 	journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4833 	if (IS_ERR(journal_inode)) {
4834 		ext4_msg(sb, KERN_ERR, "no journal found");
4835 		return NULL;
4836 	}
4837 	if (!journal_inode->i_nlink) {
4838 		make_bad_inode(journal_inode);
4839 		iput(journal_inode);
4840 		ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4841 		return NULL;
4842 	}
4843 
4844 	jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4845 		  journal_inode, journal_inode->i_size);
4846 	if (!S_ISREG(journal_inode->i_mode)) {
4847 		ext4_msg(sb, KERN_ERR, "invalid journal inode");
4848 		iput(journal_inode);
4849 		return NULL;
4850 	}
4851 	return journal_inode;
4852 }
4853 
4854 static journal_t *ext4_get_journal(struct super_block *sb,
4855 				   unsigned int journal_inum)
4856 {
4857 	struct inode *journal_inode;
4858 	journal_t *journal;
4859 
4860 	BUG_ON(!ext4_has_feature_journal(sb));
4861 
4862 	journal_inode = ext4_get_journal_inode(sb, journal_inum);
4863 	if (!journal_inode)
4864 		return NULL;
4865 
4866 	journal = jbd2_journal_init_inode(journal_inode);
4867 	if (!journal) {
4868 		ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4869 		iput(journal_inode);
4870 		return NULL;
4871 	}
4872 	journal->j_private = sb;
4873 	ext4_init_journal_params(sb, journal);
4874 	return journal;
4875 }
4876 
4877 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4878 				       dev_t j_dev)
4879 {
4880 	struct buffer_head *bh;
4881 	journal_t *journal;
4882 	ext4_fsblk_t start;
4883 	ext4_fsblk_t len;
4884 	int hblock, blocksize;
4885 	ext4_fsblk_t sb_block;
4886 	unsigned long offset;
4887 	struct ext4_super_block *es;
4888 	struct block_device *bdev;
4889 
4890 	BUG_ON(!ext4_has_feature_journal(sb));
4891 
4892 	bdev = ext4_blkdev_get(j_dev, sb);
4893 	if (bdev == NULL)
4894 		return NULL;
4895 
4896 	blocksize = sb->s_blocksize;
4897 	hblock = bdev_logical_block_size(bdev);
4898 	if (blocksize < hblock) {
4899 		ext4_msg(sb, KERN_ERR,
4900 			"blocksize too small for journal device");
4901 		goto out_bdev;
4902 	}
4903 
4904 	sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4905 	offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4906 	set_blocksize(bdev, blocksize);
4907 	if (!(bh = __bread(bdev, sb_block, blocksize))) {
4908 		ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4909 		       "external journal");
4910 		goto out_bdev;
4911 	}
4912 
4913 	es = (struct ext4_super_block *) (bh->b_data + offset);
4914 	if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4915 	    !(le32_to_cpu(es->s_feature_incompat) &
4916 	      EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4917 		ext4_msg(sb, KERN_ERR, "external journal has "
4918 					"bad superblock");
4919 		brelse(bh);
4920 		goto out_bdev;
4921 	}
4922 
4923 	if ((le32_to_cpu(es->s_feature_ro_compat) &
4924 	     EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4925 	    es->s_checksum != ext4_superblock_csum(sb, es)) {
4926 		ext4_msg(sb, KERN_ERR, "external journal has "
4927 				       "corrupt superblock");
4928 		brelse(bh);
4929 		goto out_bdev;
4930 	}
4931 
4932 	if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4933 		ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4934 		brelse(bh);
4935 		goto out_bdev;
4936 	}
4937 
4938 	len = ext4_blocks_count(es);
4939 	start = sb_block + 1;
4940 	brelse(bh);	/* we're done with the superblock */
4941 
4942 	journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4943 					start, len, blocksize);
4944 	if (!journal) {
4945 		ext4_msg(sb, KERN_ERR, "failed to create device journal");
4946 		goto out_bdev;
4947 	}
4948 	journal->j_private = sb;
4949 	ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4950 	wait_on_buffer(journal->j_sb_buffer);
4951 	if (!buffer_uptodate(journal->j_sb_buffer)) {
4952 		ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4953 		goto out_journal;
4954 	}
4955 	if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4956 		ext4_msg(sb, KERN_ERR, "External journal has more than one "
4957 					"user (unsupported) - %d",
4958 			be32_to_cpu(journal->j_superblock->s_nr_users));
4959 		goto out_journal;
4960 	}
4961 	EXT4_SB(sb)->journal_bdev = bdev;
4962 	ext4_init_journal_params(sb, journal);
4963 	return journal;
4964 
4965 out_journal:
4966 	jbd2_journal_destroy(journal);
4967 out_bdev:
4968 	ext4_blkdev_put(bdev);
4969 	return NULL;
4970 }
4971 
4972 static int ext4_load_journal(struct super_block *sb,
4973 			     struct ext4_super_block *es,
4974 			     unsigned long journal_devnum)
4975 {
4976 	journal_t *journal;
4977 	unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4978 	dev_t journal_dev;
4979 	int err = 0;
4980 	int really_read_only;
4981 
4982 	BUG_ON(!ext4_has_feature_journal(sb));
4983 
4984 	if (journal_devnum &&
4985 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4986 		ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4987 			"numbers have changed");
4988 		journal_dev = new_decode_dev(journal_devnum);
4989 	} else
4990 		journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4991 
4992 	really_read_only = bdev_read_only(sb->s_bdev);
4993 
4994 	/*
4995 	 * Are we loading a blank journal or performing recovery after a
4996 	 * crash?  For recovery, we need to check in advance whether we
4997 	 * can get read-write access to the device.
4998 	 */
4999 	if (ext4_has_feature_journal_needs_recovery(sb)) {
5000 		if (sb_rdonly(sb)) {
5001 			ext4_msg(sb, KERN_INFO, "INFO: recovery "
5002 					"required on readonly filesystem");
5003 			if (really_read_only) {
5004 				ext4_msg(sb, KERN_ERR, "write access "
5005 					"unavailable, cannot proceed "
5006 					"(try mounting with noload)");
5007 				return -EROFS;
5008 			}
5009 			ext4_msg(sb, KERN_INFO, "write access will "
5010 			       "be enabled during recovery");
5011 		}
5012 	}
5013 
5014 	if (journal_inum && journal_dev) {
5015 		ext4_msg(sb, KERN_ERR, "filesystem has both journal "
5016 		       "and inode journals!");
5017 		return -EINVAL;
5018 	}
5019 
5020 	if (journal_inum) {
5021 		if (!(journal = ext4_get_journal(sb, journal_inum)))
5022 			return -EINVAL;
5023 	} else {
5024 		if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
5025 			return -EINVAL;
5026 	}
5027 
5028 	if (!(journal->j_flags & JBD2_BARRIER))
5029 		ext4_msg(sb, KERN_INFO, "barriers disabled");
5030 
5031 	if (!ext4_has_feature_journal_needs_recovery(sb))
5032 		err = jbd2_journal_wipe(journal, !really_read_only);
5033 	if (!err) {
5034 		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5035 		if (save)
5036 			memcpy(save, ((char *) es) +
5037 			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5038 		err = jbd2_journal_load(journal);
5039 		if (save)
5040 			memcpy(((char *) es) + EXT4_S_ERR_START,
5041 			       save, EXT4_S_ERR_LEN);
5042 		kfree(save);
5043 	}
5044 
5045 	if (err) {
5046 		ext4_msg(sb, KERN_ERR, "error loading journal");
5047 		jbd2_journal_destroy(journal);
5048 		return err;
5049 	}
5050 
5051 	EXT4_SB(sb)->s_journal = journal;
5052 	ext4_clear_journal_err(sb, es);
5053 
5054 	if (!really_read_only && journal_devnum &&
5055 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5056 		es->s_journal_dev = cpu_to_le32(journal_devnum);
5057 
5058 		/* Make sure we flush the recovery flag to disk. */
5059 		ext4_commit_super(sb, 1);
5060 	}
5061 
5062 	return 0;
5063 }
5064 
5065 static int ext4_commit_super(struct super_block *sb, int sync)
5066 {
5067 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5068 	struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5069 	int error = 0;
5070 
5071 	if (!sbh || block_device_ejected(sb))
5072 		return error;
5073 
5074 	/*
5075 	 * The superblock bh should be mapped, but it might not be if the
5076 	 * device was hot-removed. Not much we can do but fail the I/O.
5077 	 */
5078 	if (!buffer_mapped(sbh))
5079 		return error;
5080 
5081 	/*
5082 	 * If the file system is mounted read-only, don't update the
5083 	 * superblock write time.  This avoids updating the superblock
5084 	 * write time when we are mounting the root file system
5085 	 * read/only but we need to replay the journal; at that point,
5086 	 * for people who are east of GMT and who make their clock
5087 	 * tick in localtime for Windows bug-for-bug compatibility,
5088 	 * the clock is set in the future, and this will cause e2fsck
5089 	 * to complain and force a full file system check.
5090 	 */
5091 	if (!(sb->s_flags & SB_RDONLY))
5092 		ext4_update_tstamp(es, s_wtime);
5093 	if (sb->s_bdev->bd_part)
5094 		es->s_kbytes_written =
5095 			cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5096 			    ((part_stat_read(sb->s_bdev->bd_part,
5097 					     sectors[STAT_WRITE]) -
5098 			      EXT4_SB(sb)->s_sectors_written_start) >> 1));
5099 	else
5100 		es->s_kbytes_written =
5101 			cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5102 	if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5103 		ext4_free_blocks_count_set(es,
5104 			EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5105 				&EXT4_SB(sb)->s_freeclusters_counter)));
5106 	if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5107 		es->s_free_inodes_count =
5108 			cpu_to_le32(percpu_counter_sum_positive(
5109 				&EXT4_SB(sb)->s_freeinodes_counter));
5110 	BUFFER_TRACE(sbh, "marking dirty");
5111 	ext4_superblock_csum_set(sb);
5112 	if (sync)
5113 		lock_buffer(sbh);
5114 	if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5115 		/*
5116 		 * Oh, dear.  A previous attempt to write the
5117 		 * superblock failed.  This could happen because the
5118 		 * USB device was yanked out.  Or it could happen to
5119 		 * be a transient write error and maybe the block will
5120 		 * be remapped.  Nothing we can do but to retry the
5121 		 * write and hope for the best.
5122 		 */
5123 		ext4_msg(sb, KERN_ERR, "previous I/O error to "
5124 		       "superblock detected");
5125 		clear_buffer_write_io_error(sbh);
5126 		set_buffer_uptodate(sbh);
5127 	}
5128 	mark_buffer_dirty(sbh);
5129 	if (sync) {
5130 		unlock_buffer(sbh);
5131 		error = __sync_dirty_buffer(sbh,
5132 			REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5133 		if (buffer_write_io_error(sbh)) {
5134 			ext4_msg(sb, KERN_ERR, "I/O error while writing "
5135 			       "superblock");
5136 			clear_buffer_write_io_error(sbh);
5137 			set_buffer_uptodate(sbh);
5138 		}
5139 	}
5140 	return error;
5141 }
5142 
5143 /*
5144  * Have we just finished recovery?  If so, and if we are mounting (or
5145  * remounting) the filesystem readonly, then we will end up with a
5146  * consistent fs on disk.  Record that fact.
5147  */
5148 static void ext4_mark_recovery_complete(struct super_block *sb,
5149 					struct ext4_super_block *es)
5150 {
5151 	journal_t *journal = EXT4_SB(sb)->s_journal;
5152 
5153 	if (!ext4_has_feature_journal(sb)) {
5154 		BUG_ON(journal != NULL);
5155 		return;
5156 	}
5157 	jbd2_journal_lock_updates(journal);
5158 	if (jbd2_journal_flush(journal) < 0)
5159 		goto out;
5160 
5161 	if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5162 		ext4_clear_feature_journal_needs_recovery(sb);
5163 		ext4_commit_super(sb, 1);
5164 	}
5165 
5166 out:
5167 	jbd2_journal_unlock_updates(journal);
5168 }
5169 
5170 /*
5171  * If we are mounting (or read-write remounting) a filesystem whose journal
5172  * has recorded an error from a previous lifetime, move that error to the
5173  * main filesystem now.
5174  */
5175 static void ext4_clear_journal_err(struct super_block *sb,
5176 				   struct ext4_super_block *es)
5177 {
5178 	journal_t *journal;
5179 	int j_errno;
5180 	const char *errstr;
5181 
5182 	BUG_ON(!ext4_has_feature_journal(sb));
5183 
5184 	journal = EXT4_SB(sb)->s_journal;
5185 
5186 	/*
5187 	 * Now check for any error status which may have been recorded in the
5188 	 * journal by a prior ext4_error() or ext4_abort()
5189 	 */
5190 
5191 	j_errno = jbd2_journal_errno(journal);
5192 	if (j_errno) {
5193 		char nbuf[16];
5194 
5195 		errstr = ext4_decode_error(sb, j_errno, nbuf);
5196 		ext4_warning(sb, "Filesystem error recorded "
5197 			     "from previous mount: %s", errstr);
5198 		ext4_warning(sb, "Marking fs in need of filesystem check.");
5199 
5200 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5201 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5202 		ext4_commit_super(sb, 1);
5203 
5204 		jbd2_journal_clear_err(journal);
5205 		jbd2_journal_update_sb_errno(journal);
5206 	}
5207 }
5208 
5209 /*
5210  * Force the running and committing transactions to commit,
5211  * and wait on the commit.
5212  */
5213 int ext4_force_commit(struct super_block *sb)
5214 {
5215 	journal_t *journal;
5216 
5217 	if (sb_rdonly(sb))
5218 		return 0;
5219 
5220 	journal = EXT4_SB(sb)->s_journal;
5221 	return ext4_journal_force_commit(journal);
5222 }
5223 
5224 static int ext4_sync_fs(struct super_block *sb, int wait)
5225 {
5226 	int ret = 0;
5227 	tid_t target;
5228 	bool needs_barrier = false;
5229 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5230 
5231 	if (unlikely(ext4_forced_shutdown(sbi)))
5232 		return 0;
5233 
5234 	trace_ext4_sync_fs(sb, wait);
5235 	flush_workqueue(sbi->rsv_conversion_wq);
5236 	/*
5237 	 * Writeback quota in non-journalled quota case - journalled quota has
5238 	 * no dirty dquots
5239 	 */
5240 	dquot_writeback_dquots(sb, -1);
5241 	/*
5242 	 * Data writeback is possible w/o journal transaction, so barrier must
5243 	 * being sent at the end of the function. But we can skip it if
5244 	 * transaction_commit will do it for us.
5245 	 */
5246 	if (sbi->s_journal) {
5247 		target = jbd2_get_latest_transaction(sbi->s_journal);
5248 		if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5249 		    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5250 			needs_barrier = true;
5251 
5252 		if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5253 			if (wait)
5254 				ret = jbd2_log_wait_commit(sbi->s_journal,
5255 							   target);
5256 		}
5257 	} else if (wait && test_opt(sb, BARRIER))
5258 		needs_barrier = true;
5259 	if (needs_barrier) {
5260 		int err;
5261 		err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
5262 		if (!ret)
5263 			ret = err;
5264 	}
5265 
5266 	return ret;
5267 }
5268 
5269 /*
5270  * LVM calls this function before a (read-only) snapshot is created.  This
5271  * gives us a chance to flush the journal completely and mark the fs clean.
5272  *
5273  * Note that only this function cannot bring a filesystem to be in a clean
5274  * state independently. It relies on upper layer to stop all data & metadata
5275  * modifications.
5276  */
5277 static int ext4_freeze(struct super_block *sb)
5278 {
5279 	int error = 0;
5280 	journal_t *journal;
5281 
5282 	if (sb_rdonly(sb))
5283 		return 0;
5284 
5285 	journal = EXT4_SB(sb)->s_journal;
5286 
5287 	if (journal) {
5288 		/* Now we set up the journal barrier. */
5289 		jbd2_journal_lock_updates(journal);
5290 
5291 		/*
5292 		 * Don't clear the needs_recovery flag if we failed to
5293 		 * flush the journal.
5294 		 */
5295 		error = jbd2_journal_flush(journal);
5296 		if (error < 0)
5297 			goto out;
5298 
5299 		/* Journal blocked and flushed, clear needs_recovery flag. */
5300 		ext4_clear_feature_journal_needs_recovery(sb);
5301 	}
5302 
5303 	error = ext4_commit_super(sb, 1);
5304 out:
5305 	if (journal)
5306 		/* we rely on upper layer to stop further updates */
5307 		jbd2_journal_unlock_updates(journal);
5308 	return error;
5309 }
5310 
5311 /*
5312  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5313  * flag here, even though the filesystem is not technically dirty yet.
5314  */
5315 static int ext4_unfreeze(struct super_block *sb)
5316 {
5317 	if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5318 		return 0;
5319 
5320 	if (EXT4_SB(sb)->s_journal) {
5321 		/* Reset the needs_recovery flag before the fs is unlocked. */
5322 		ext4_set_feature_journal_needs_recovery(sb);
5323 	}
5324 
5325 	ext4_commit_super(sb, 1);
5326 	return 0;
5327 }
5328 
5329 /*
5330  * Structure to save mount options for ext4_remount's benefit
5331  */
5332 struct ext4_mount_options {
5333 	unsigned long s_mount_opt;
5334 	unsigned long s_mount_opt2;
5335 	kuid_t s_resuid;
5336 	kgid_t s_resgid;
5337 	unsigned long s_commit_interval;
5338 	u32 s_min_batch_time, s_max_batch_time;
5339 #ifdef CONFIG_QUOTA
5340 	int s_jquota_fmt;
5341 	char *s_qf_names[EXT4_MAXQUOTAS];
5342 #endif
5343 };
5344 
5345 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5346 {
5347 	struct ext4_super_block *es;
5348 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5349 	unsigned long old_sb_flags;
5350 	struct ext4_mount_options old_opts;
5351 	int enable_quota = 0;
5352 	ext4_group_t g;
5353 	unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5354 	int err = 0;
5355 #ifdef CONFIG_QUOTA
5356 	int i, j;
5357 	char *to_free[EXT4_MAXQUOTAS];
5358 #endif
5359 	char *orig_data = kstrdup(data, GFP_KERNEL);
5360 
5361 	if (data && !orig_data)
5362 		return -ENOMEM;
5363 
5364 	/* Store the original options */
5365 	old_sb_flags = sb->s_flags;
5366 	old_opts.s_mount_opt = sbi->s_mount_opt;
5367 	old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5368 	old_opts.s_resuid = sbi->s_resuid;
5369 	old_opts.s_resgid = sbi->s_resgid;
5370 	old_opts.s_commit_interval = sbi->s_commit_interval;
5371 	old_opts.s_min_batch_time = sbi->s_min_batch_time;
5372 	old_opts.s_max_batch_time = sbi->s_max_batch_time;
5373 #ifdef CONFIG_QUOTA
5374 	old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5375 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5376 		if (sbi->s_qf_names[i]) {
5377 			char *qf_name = get_qf_name(sb, sbi, i);
5378 
5379 			old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5380 			if (!old_opts.s_qf_names[i]) {
5381 				for (j = 0; j < i; j++)
5382 					kfree(old_opts.s_qf_names[j]);
5383 				kfree(orig_data);
5384 				return -ENOMEM;
5385 			}
5386 		} else
5387 			old_opts.s_qf_names[i] = NULL;
5388 #endif
5389 	if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5390 		journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5391 
5392 	if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5393 		err = -EINVAL;
5394 		goto restore_opts;
5395 	}
5396 
5397 	if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5398 	    test_opt(sb, JOURNAL_CHECKSUM)) {
5399 		ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5400 			 "during remount not supported; ignoring");
5401 		sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5402 	}
5403 
5404 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5405 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5406 			ext4_msg(sb, KERN_ERR, "can't mount with "
5407 				 "both data=journal and delalloc");
5408 			err = -EINVAL;
5409 			goto restore_opts;
5410 		}
5411 		if (test_opt(sb, DIOREAD_NOLOCK)) {
5412 			ext4_msg(sb, KERN_ERR, "can't mount with "
5413 				 "both data=journal and dioread_nolock");
5414 			err = -EINVAL;
5415 			goto restore_opts;
5416 		}
5417 		if (test_opt(sb, DAX)) {
5418 			ext4_msg(sb, KERN_ERR, "can't mount with "
5419 				 "both data=journal and dax");
5420 			err = -EINVAL;
5421 			goto restore_opts;
5422 		}
5423 	} else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5424 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5425 			ext4_msg(sb, KERN_ERR, "can't mount with "
5426 				"journal_async_commit in data=ordered mode");
5427 			err = -EINVAL;
5428 			goto restore_opts;
5429 		}
5430 	}
5431 
5432 	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5433 		ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5434 		err = -EINVAL;
5435 		goto restore_opts;
5436 	}
5437 
5438 	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5439 		ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5440 			"dax flag with busy inodes while remounting");
5441 		sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5442 	}
5443 
5444 	if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5445 		ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5446 
5447 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5448 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5449 
5450 	es = sbi->s_es;
5451 
5452 	if (sbi->s_journal) {
5453 		ext4_init_journal_params(sb, sbi->s_journal);
5454 		set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5455 	}
5456 
5457 	if (*flags & SB_LAZYTIME)
5458 		sb->s_flags |= SB_LAZYTIME;
5459 
5460 	if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5461 		if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5462 			err = -EROFS;
5463 			goto restore_opts;
5464 		}
5465 
5466 		if (*flags & SB_RDONLY) {
5467 			err = sync_filesystem(sb);
5468 			if (err < 0)
5469 				goto restore_opts;
5470 			err = dquot_suspend(sb, -1);
5471 			if (err < 0)
5472 				goto restore_opts;
5473 
5474 			/*
5475 			 * First of all, the unconditional stuff we have to do
5476 			 * to disable replay of the journal when we next remount
5477 			 */
5478 			sb->s_flags |= SB_RDONLY;
5479 
5480 			/*
5481 			 * OK, test if we are remounting a valid rw partition
5482 			 * readonly, and if so set the rdonly flag and then
5483 			 * mark the partition as valid again.
5484 			 */
5485 			if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5486 			    (sbi->s_mount_state & EXT4_VALID_FS))
5487 				es->s_state = cpu_to_le16(sbi->s_mount_state);
5488 
5489 			if (sbi->s_journal)
5490 				ext4_mark_recovery_complete(sb, es);
5491 			if (sbi->s_mmp_tsk)
5492 				kthread_stop(sbi->s_mmp_tsk);
5493 		} else {
5494 			/* Make sure we can mount this feature set readwrite */
5495 			if (ext4_has_feature_readonly(sb) ||
5496 			    !ext4_feature_set_ok(sb, 0)) {
5497 				err = -EROFS;
5498 				goto restore_opts;
5499 			}
5500 			/*
5501 			 * Make sure the group descriptor checksums
5502 			 * are sane.  If they aren't, refuse to remount r/w.
5503 			 */
5504 			for (g = 0; g < sbi->s_groups_count; g++) {
5505 				struct ext4_group_desc *gdp =
5506 					ext4_get_group_desc(sb, g, NULL);
5507 
5508 				if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5509 					ext4_msg(sb, KERN_ERR,
5510 	       "ext4_remount: Checksum for group %u failed (%u!=%u)",
5511 		g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5512 					       le16_to_cpu(gdp->bg_checksum));
5513 					err = -EFSBADCRC;
5514 					goto restore_opts;
5515 				}
5516 			}
5517 
5518 			/*
5519 			 * If we have an unprocessed orphan list hanging
5520 			 * around from a previously readonly bdev mount,
5521 			 * require a full umount/remount for now.
5522 			 */
5523 			if (es->s_last_orphan) {
5524 				ext4_msg(sb, KERN_WARNING, "Couldn't "
5525 				       "remount RDWR because of unprocessed "
5526 				       "orphan inode list.  Please "
5527 				       "umount/remount instead");
5528 				err = -EINVAL;
5529 				goto restore_opts;
5530 			}
5531 
5532 			/*
5533 			 * Mounting a RDONLY partition read-write, so reread
5534 			 * and store the current valid flag.  (It may have
5535 			 * been changed by e2fsck since we originally mounted
5536 			 * the partition.)
5537 			 */
5538 			if (sbi->s_journal)
5539 				ext4_clear_journal_err(sb, es);
5540 			sbi->s_mount_state = le16_to_cpu(es->s_state);
5541 
5542 			err = ext4_setup_super(sb, es, 0);
5543 			if (err)
5544 				goto restore_opts;
5545 
5546 			sb->s_flags &= ~SB_RDONLY;
5547 			if (ext4_has_feature_mmp(sb))
5548 				if (ext4_multi_mount_protect(sb,
5549 						le64_to_cpu(es->s_mmp_block))) {
5550 					err = -EROFS;
5551 					goto restore_opts;
5552 				}
5553 			enable_quota = 1;
5554 		}
5555 	}
5556 
5557 	/*
5558 	 * Reinitialize lazy itable initialization thread based on
5559 	 * current settings
5560 	 */
5561 	if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5562 		ext4_unregister_li_request(sb);
5563 	else {
5564 		ext4_group_t first_not_zeroed;
5565 		first_not_zeroed = ext4_has_uninit_itable(sb);
5566 		ext4_register_li_request(sb, first_not_zeroed);
5567 	}
5568 
5569 	ext4_setup_system_zone(sb);
5570 	if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5571 		err = ext4_commit_super(sb, 1);
5572 		if (err)
5573 			goto restore_opts;
5574 	}
5575 
5576 #ifdef CONFIG_QUOTA
5577 	/* Release old quota file names */
5578 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5579 		kfree(old_opts.s_qf_names[i]);
5580 	if (enable_quota) {
5581 		if (sb_any_quota_suspended(sb))
5582 			dquot_resume(sb, -1);
5583 		else if (ext4_has_feature_quota(sb)) {
5584 			err = ext4_enable_quotas(sb);
5585 			if (err)
5586 				goto restore_opts;
5587 		}
5588 	}
5589 #endif
5590 
5591 	*flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5592 	ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5593 	kfree(orig_data);
5594 	return 0;
5595 
5596 restore_opts:
5597 	sb->s_flags = old_sb_flags;
5598 	sbi->s_mount_opt = old_opts.s_mount_opt;
5599 	sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5600 	sbi->s_resuid = old_opts.s_resuid;
5601 	sbi->s_resgid = old_opts.s_resgid;
5602 	sbi->s_commit_interval = old_opts.s_commit_interval;
5603 	sbi->s_min_batch_time = old_opts.s_min_batch_time;
5604 	sbi->s_max_batch_time = old_opts.s_max_batch_time;
5605 #ifdef CONFIG_QUOTA
5606 	sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5607 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5608 		to_free[i] = get_qf_name(sb, sbi, i);
5609 		rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5610 	}
5611 	synchronize_rcu();
5612 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5613 		kfree(to_free[i]);
5614 #endif
5615 	kfree(orig_data);
5616 	return err;
5617 }
5618 
5619 #ifdef CONFIG_QUOTA
5620 static int ext4_statfs_project(struct super_block *sb,
5621 			       kprojid_t projid, struct kstatfs *buf)
5622 {
5623 	struct kqid qid;
5624 	struct dquot *dquot;
5625 	u64 limit;
5626 	u64 curblock;
5627 
5628 	qid = make_kqid_projid(projid);
5629 	dquot = dqget(sb, qid);
5630 	if (IS_ERR(dquot))
5631 		return PTR_ERR(dquot);
5632 	spin_lock(&dquot->dq_dqb_lock);
5633 
5634 	limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
5635 			     dquot->dq_dqb.dqb_bhardlimit);
5636 	limit >>= sb->s_blocksize_bits;
5637 
5638 	if (limit && buf->f_blocks > limit) {
5639 		curblock = (dquot->dq_dqb.dqb_curspace +
5640 			    dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5641 		buf->f_blocks = limit;
5642 		buf->f_bfree = buf->f_bavail =
5643 			(buf->f_blocks > curblock) ?
5644 			 (buf->f_blocks - curblock) : 0;
5645 	}
5646 
5647 	limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
5648 			     dquot->dq_dqb.dqb_ihardlimit);
5649 	if (limit && buf->f_files > limit) {
5650 		buf->f_files = limit;
5651 		buf->f_ffree =
5652 			(buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5653 			 (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5654 	}
5655 
5656 	spin_unlock(&dquot->dq_dqb_lock);
5657 	dqput(dquot);
5658 	return 0;
5659 }
5660 #endif
5661 
5662 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5663 {
5664 	struct super_block *sb = dentry->d_sb;
5665 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5666 	struct ext4_super_block *es = sbi->s_es;
5667 	ext4_fsblk_t overhead = 0, resv_blocks;
5668 	u64 fsid;
5669 	s64 bfree;
5670 	resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5671 
5672 	if (!test_opt(sb, MINIX_DF))
5673 		overhead = sbi->s_overhead;
5674 
5675 	buf->f_type = EXT4_SUPER_MAGIC;
5676 	buf->f_bsize = sb->s_blocksize;
5677 	buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5678 	bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5679 		percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5680 	/* prevent underflow in case that few free space is available */
5681 	buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5682 	buf->f_bavail = buf->f_bfree -
5683 			(ext4_r_blocks_count(es) + resv_blocks);
5684 	if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5685 		buf->f_bavail = 0;
5686 	buf->f_files = le32_to_cpu(es->s_inodes_count);
5687 	buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5688 	buf->f_namelen = EXT4_NAME_LEN;
5689 	fsid = le64_to_cpup((void *)es->s_uuid) ^
5690 	       le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5691 	buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5692 	buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5693 
5694 #ifdef CONFIG_QUOTA
5695 	if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5696 	    sb_has_quota_limits_enabled(sb, PRJQUOTA))
5697 		ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5698 #endif
5699 	return 0;
5700 }
5701 
5702 
5703 #ifdef CONFIG_QUOTA
5704 
5705 /*
5706  * Helper functions so that transaction is started before we acquire dqio_sem
5707  * to keep correct lock ordering of transaction > dqio_sem
5708  */
5709 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5710 {
5711 	return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5712 }
5713 
5714 static int ext4_write_dquot(struct dquot *dquot)
5715 {
5716 	int ret, err;
5717 	handle_t *handle;
5718 	struct inode *inode;
5719 
5720 	inode = dquot_to_inode(dquot);
5721 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5722 				    EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5723 	if (IS_ERR(handle))
5724 		return PTR_ERR(handle);
5725 	ret = dquot_commit(dquot);
5726 	err = ext4_journal_stop(handle);
5727 	if (!ret)
5728 		ret = err;
5729 	return ret;
5730 }
5731 
5732 static int ext4_acquire_dquot(struct dquot *dquot)
5733 {
5734 	int ret, err;
5735 	handle_t *handle;
5736 
5737 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5738 				    EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5739 	if (IS_ERR(handle))
5740 		return PTR_ERR(handle);
5741 	ret = dquot_acquire(dquot);
5742 	err = ext4_journal_stop(handle);
5743 	if (!ret)
5744 		ret = err;
5745 	return ret;
5746 }
5747 
5748 static int ext4_release_dquot(struct dquot *dquot)
5749 {
5750 	int ret, err;
5751 	handle_t *handle;
5752 
5753 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5754 				    EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5755 	if (IS_ERR(handle)) {
5756 		/* Release dquot anyway to avoid endless cycle in dqput() */
5757 		dquot_release(dquot);
5758 		return PTR_ERR(handle);
5759 	}
5760 	ret = dquot_release(dquot);
5761 	err = ext4_journal_stop(handle);
5762 	if (!ret)
5763 		ret = err;
5764 	return ret;
5765 }
5766 
5767 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5768 {
5769 	struct super_block *sb = dquot->dq_sb;
5770 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5771 
5772 	/* Are we journaling quotas? */
5773 	if (ext4_has_feature_quota(sb) ||
5774 	    sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5775 		dquot_mark_dquot_dirty(dquot);
5776 		return ext4_write_dquot(dquot);
5777 	} else {
5778 		return dquot_mark_dquot_dirty(dquot);
5779 	}
5780 }
5781 
5782 static int ext4_write_info(struct super_block *sb, int type)
5783 {
5784 	int ret, err;
5785 	handle_t *handle;
5786 
5787 	/* Data block + inode block */
5788 	handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5789 	if (IS_ERR(handle))
5790 		return PTR_ERR(handle);
5791 	ret = dquot_commit_info(sb, type);
5792 	err = ext4_journal_stop(handle);
5793 	if (!ret)
5794 		ret = err;
5795 	return ret;
5796 }
5797 
5798 /*
5799  * Turn on quotas during mount time - we need to find
5800  * the quota file and such...
5801  */
5802 static int ext4_quota_on_mount(struct super_block *sb, int type)
5803 {
5804 	return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5805 					EXT4_SB(sb)->s_jquota_fmt, type);
5806 }
5807 
5808 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5809 {
5810 	struct ext4_inode_info *ei = EXT4_I(inode);
5811 
5812 	/* The first argument of lockdep_set_subclass has to be
5813 	 * *exactly* the same as the argument to init_rwsem() --- in
5814 	 * this case, in init_once() --- or lockdep gets unhappy
5815 	 * because the name of the lock is set using the
5816 	 * stringification of the argument to init_rwsem().
5817 	 */
5818 	(void) ei;	/* shut up clang warning if !CONFIG_LOCKDEP */
5819 	lockdep_set_subclass(&ei->i_data_sem, subclass);
5820 }
5821 
5822 /*
5823  * Standard function to be called on quota_on
5824  */
5825 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5826 			 const struct path *path)
5827 {
5828 	int err;
5829 
5830 	if (!test_opt(sb, QUOTA))
5831 		return -EINVAL;
5832 
5833 	/* Quotafile not on the same filesystem? */
5834 	if (path->dentry->d_sb != sb)
5835 		return -EXDEV;
5836 	/* Journaling quota? */
5837 	if (EXT4_SB(sb)->s_qf_names[type]) {
5838 		/* Quotafile not in fs root? */
5839 		if (path->dentry->d_parent != sb->s_root)
5840 			ext4_msg(sb, KERN_WARNING,
5841 				"Quota file not on filesystem root. "
5842 				"Journaled quota will not work");
5843 		sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5844 	} else {
5845 		/*
5846 		 * Clear the flag just in case mount options changed since
5847 		 * last time.
5848 		 */
5849 		sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5850 	}
5851 
5852 	/*
5853 	 * When we journal data on quota file, we have to flush journal to see
5854 	 * all updates to the file when we bypass pagecache...
5855 	 */
5856 	if (EXT4_SB(sb)->s_journal &&
5857 	    ext4_should_journal_data(d_inode(path->dentry))) {
5858 		/*
5859 		 * We don't need to lock updates but journal_flush() could
5860 		 * otherwise be livelocked...
5861 		 */
5862 		jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5863 		err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5864 		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5865 		if (err)
5866 			return err;
5867 	}
5868 
5869 	lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5870 	err = dquot_quota_on(sb, type, format_id, path);
5871 	if (err) {
5872 		lockdep_set_quota_inode(path->dentry->d_inode,
5873 					     I_DATA_SEM_NORMAL);
5874 	} else {
5875 		struct inode *inode = d_inode(path->dentry);
5876 		handle_t *handle;
5877 
5878 		/*
5879 		 * Set inode flags to prevent userspace from messing with quota
5880 		 * files. If this fails, we return success anyway since quotas
5881 		 * are already enabled and this is not a hard failure.
5882 		 */
5883 		inode_lock(inode);
5884 		handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5885 		if (IS_ERR(handle))
5886 			goto unlock_inode;
5887 		EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5888 		inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5889 				S_NOATIME | S_IMMUTABLE);
5890 		ext4_mark_inode_dirty(handle, inode);
5891 		ext4_journal_stop(handle);
5892 	unlock_inode:
5893 		inode_unlock(inode);
5894 	}
5895 	return err;
5896 }
5897 
5898 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5899 			     unsigned int flags)
5900 {
5901 	int err;
5902 	struct inode *qf_inode;
5903 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5904 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5905 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5906 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5907 	};
5908 
5909 	BUG_ON(!ext4_has_feature_quota(sb));
5910 
5911 	if (!qf_inums[type])
5912 		return -EPERM;
5913 
5914 	qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5915 	if (IS_ERR(qf_inode)) {
5916 		ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5917 		return PTR_ERR(qf_inode);
5918 	}
5919 
5920 	/* Don't account quota for quota files to avoid recursion */
5921 	qf_inode->i_flags |= S_NOQUOTA;
5922 	lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5923 	err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
5924 	if (err)
5925 		lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5926 	iput(qf_inode);
5927 
5928 	return err;
5929 }
5930 
5931 /* Enable usage tracking for all quota types. */
5932 static int ext4_enable_quotas(struct super_block *sb)
5933 {
5934 	int type, err = 0;
5935 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5936 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5937 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5938 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5939 	};
5940 	bool quota_mopt[EXT4_MAXQUOTAS] = {
5941 		test_opt(sb, USRQUOTA),
5942 		test_opt(sb, GRPQUOTA),
5943 		test_opt(sb, PRJQUOTA),
5944 	};
5945 
5946 	sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5947 	for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5948 		if (qf_inums[type]) {
5949 			err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5950 				DQUOT_USAGE_ENABLED |
5951 				(quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5952 			if (err) {
5953 				ext4_warning(sb,
5954 					"Failed to enable quota tracking "
5955 					"(type=%d, err=%d). Please run "
5956 					"e2fsck to fix.", type, err);
5957 				for (type--; type >= 0; type--)
5958 					dquot_quota_off(sb, type);
5959 
5960 				return err;
5961 			}
5962 		}
5963 	}
5964 	return 0;
5965 }
5966 
5967 static int ext4_quota_off(struct super_block *sb, int type)
5968 {
5969 	struct inode *inode = sb_dqopt(sb)->files[type];
5970 	handle_t *handle;
5971 	int err;
5972 
5973 	/* Force all delayed allocation blocks to be allocated.
5974 	 * Caller already holds s_umount sem */
5975 	if (test_opt(sb, DELALLOC))
5976 		sync_filesystem(sb);
5977 
5978 	if (!inode || !igrab(inode))
5979 		goto out;
5980 
5981 	err = dquot_quota_off(sb, type);
5982 	if (err || ext4_has_feature_quota(sb))
5983 		goto out_put;
5984 
5985 	inode_lock(inode);
5986 	/*
5987 	 * Update modification times of quota files when userspace can
5988 	 * start looking at them. If we fail, we return success anyway since
5989 	 * this is not a hard failure and quotas are already disabled.
5990 	 */
5991 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5992 	if (IS_ERR(handle))
5993 		goto out_unlock;
5994 	EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5995 	inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5996 	inode->i_mtime = inode->i_ctime = current_time(inode);
5997 	ext4_mark_inode_dirty(handle, inode);
5998 	ext4_journal_stop(handle);
5999 out_unlock:
6000 	inode_unlock(inode);
6001 out_put:
6002 	lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6003 	iput(inode);
6004 	return err;
6005 out:
6006 	return dquot_quota_off(sb, type);
6007 }
6008 
6009 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6010  * acquiring the locks... As quota files are never truncated and quota code
6011  * itself serializes the operations (and no one else should touch the files)
6012  * we don't have to be afraid of races */
6013 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6014 			       size_t len, loff_t off)
6015 {
6016 	struct inode *inode = sb_dqopt(sb)->files[type];
6017 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6018 	int offset = off & (sb->s_blocksize - 1);
6019 	int tocopy;
6020 	size_t toread;
6021 	struct buffer_head *bh;
6022 	loff_t i_size = i_size_read(inode);
6023 
6024 	if (off > i_size)
6025 		return 0;
6026 	if (off+len > i_size)
6027 		len = i_size-off;
6028 	toread = len;
6029 	while (toread > 0) {
6030 		tocopy = sb->s_blocksize - offset < toread ?
6031 				sb->s_blocksize - offset : toread;
6032 		bh = ext4_bread(NULL, inode, blk, 0);
6033 		if (IS_ERR(bh))
6034 			return PTR_ERR(bh);
6035 		if (!bh)	/* A hole? */
6036 			memset(data, 0, tocopy);
6037 		else
6038 			memcpy(data, bh->b_data+offset, tocopy);
6039 		brelse(bh);
6040 		offset = 0;
6041 		toread -= tocopy;
6042 		data += tocopy;
6043 		blk++;
6044 	}
6045 	return len;
6046 }
6047 
6048 /* Write to quotafile (we know the transaction is already started and has
6049  * enough credits) */
6050 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6051 				const char *data, size_t len, loff_t off)
6052 {
6053 	struct inode *inode = sb_dqopt(sb)->files[type];
6054 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6055 	int err, offset = off & (sb->s_blocksize - 1);
6056 	int retries = 0;
6057 	struct buffer_head *bh;
6058 	handle_t *handle = journal_current_handle();
6059 
6060 	if (EXT4_SB(sb)->s_journal && !handle) {
6061 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6062 			" cancelled because transaction is not started",
6063 			(unsigned long long)off, (unsigned long long)len);
6064 		return -EIO;
6065 	}
6066 	/*
6067 	 * Since we account only one data block in transaction credits,
6068 	 * then it is impossible to cross a block boundary.
6069 	 */
6070 	if (sb->s_blocksize - offset < len) {
6071 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6072 			" cancelled because not block aligned",
6073 			(unsigned long long)off, (unsigned long long)len);
6074 		return -EIO;
6075 	}
6076 
6077 	do {
6078 		bh = ext4_bread(handle, inode, blk,
6079 				EXT4_GET_BLOCKS_CREATE |
6080 				EXT4_GET_BLOCKS_METADATA_NOFAIL);
6081 	} while (PTR_ERR(bh) == -ENOSPC &&
6082 		 ext4_should_retry_alloc(inode->i_sb, &retries));
6083 	if (IS_ERR(bh))
6084 		return PTR_ERR(bh);
6085 	if (!bh)
6086 		goto out;
6087 	BUFFER_TRACE(bh, "get write access");
6088 	err = ext4_journal_get_write_access(handle, bh);
6089 	if (err) {
6090 		brelse(bh);
6091 		return err;
6092 	}
6093 	lock_buffer(bh);
6094 	memcpy(bh->b_data+offset, data, len);
6095 	flush_dcache_page(bh->b_page);
6096 	unlock_buffer(bh);
6097 	err = ext4_handle_dirty_metadata(handle, NULL, bh);
6098 	brelse(bh);
6099 out:
6100 	if (inode->i_size < off + len) {
6101 		i_size_write(inode, off + len);
6102 		EXT4_I(inode)->i_disksize = inode->i_size;
6103 		ext4_mark_inode_dirty(handle, inode);
6104 	}
6105 	return len;
6106 }
6107 #endif
6108 
6109 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6110 		       const char *dev_name, void *data)
6111 {
6112 	return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6113 }
6114 
6115 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6116 static inline void register_as_ext2(void)
6117 {
6118 	int err = register_filesystem(&ext2_fs_type);
6119 	if (err)
6120 		printk(KERN_WARNING
6121 		       "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6122 }
6123 
6124 static inline void unregister_as_ext2(void)
6125 {
6126 	unregister_filesystem(&ext2_fs_type);
6127 }
6128 
6129 static inline int ext2_feature_set_ok(struct super_block *sb)
6130 {
6131 	if (ext4_has_unknown_ext2_incompat_features(sb))
6132 		return 0;
6133 	if (sb_rdonly(sb))
6134 		return 1;
6135 	if (ext4_has_unknown_ext2_ro_compat_features(sb))
6136 		return 0;
6137 	return 1;
6138 }
6139 #else
6140 static inline void register_as_ext2(void) { }
6141 static inline void unregister_as_ext2(void) { }
6142 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6143 #endif
6144 
6145 static inline void register_as_ext3(void)
6146 {
6147 	int err = register_filesystem(&ext3_fs_type);
6148 	if (err)
6149 		printk(KERN_WARNING
6150 		       "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6151 }
6152 
6153 static inline void unregister_as_ext3(void)
6154 {
6155 	unregister_filesystem(&ext3_fs_type);
6156 }
6157 
6158 static inline int ext3_feature_set_ok(struct super_block *sb)
6159 {
6160 	if (ext4_has_unknown_ext3_incompat_features(sb))
6161 		return 0;
6162 	if (!ext4_has_feature_journal(sb))
6163 		return 0;
6164 	if (sb_rdonly(sb))
6165 		return 1;
6166 	if (ext4_has_unknown_ext3_ro_compat_features(sb))
6167 		return 0;
6168 	return 1;
6169 }
6170 
6171 static struct file_system_type ext4_fs_type = {
6172 	.owner		= THIS_MODULE,
6173 	.name		= "ext4",
6174 	.mount		= ext4_mount,
6175 	.kill_sb	= kill_block_super,
6176 	.fs_flags	= FS_REQUIRES_DEV,
6177 };
6178 MODULE_ALIAS_FS("ext4");
6179 
6180 /* Shared across all ext4 file systems */
6181 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6182 
6183 static int __init ext4_init_fs(void)
6184 {
6185 	int i, err;
6186 
6187 	ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6188 	ext4_li_info = NULL;
6189 	mutex_init(&ext4_li_mtx);
6190 
6191 	/* Build-time check for flags consistency */
6192 	ext4_check_flag_values();
6193 
6194 	for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6195 		init_waitqueue_head(&ext4__ioend_wq[i]);
6196 
6197 	err = ext4_init_es();
6198 	if (err)
6199 		return err;
6200 
6201 	err = ext4_init_pending();
6202 	if (err)
6203 		goto out7;
6204 
6205 	err = ext4_init_post_read_processing();
6206 	if (err)
6207 		goto out6;
6208 
6209 	err = ext4_init_pageio();
6210 	if (err)
6211 		goto out5;
6212 
6213 	err = ext4_init_system_zone();
6214 	if (err)
6215 		goto out4;
6216 
6217 	err = ext4_init_sysfs();
6218 	if (err)
6219 		goto out3;
6220 
6221 	err = ext4_init_mballoc();
6222 	if (err)
6223 		goto out2;
6224 	err = init_inodecache();
6225 	if (err)
6226 		goto out1;
6227 	register_as_ext3();
6228 	register_as_ext2();
6229 	err = register_filesystem(&ext4_fs_type);
6230 	if (err)
6231 		goto out;
6232 
6233 	return 0;
6234 out:
6235 	unregister_as_ext2();
6236 	unregister_as_ext3();
6237 	destroy_inodecache();
6238 out1:
6239 	ext4_exit_mballoc();
6240 out2:
6241 	ext4_exit_sysfs();
6242 out3:
6243 	ext4_exit_system_zone();
6244 out4:
6245 	ext4_exit_pageio();
6246 out5:
6247 	ext4_exit_post_read_processing();
6248 out6:
6249 	ext4_exit_pending();
6250 out7:
6251 	ext4_exit_es();
6252 
6253 	return err;
6254 }
6255 
6256 static void __exit ext4_exit_fs(void)
6257 {
6258 	ext4_destroy_lazyinit_thread();
6259 	unregister_as_ext2();
6260 	unregister_as_ext3();
6261 	unregister_filesystem(&ext4_fs_type);
6262 	destroy_inodecache();
6263 	ext4_exit_mballoc();
6264 	ext4_exit_sysfs();
6265 	ext4_exit_system_zone();
6266 	ext4_exit_pageio();
6267 	ext4_exit_post_read_processing();
6268 	ext4_exit_es();
6269 	ext4_exit_pending();
6270 }
6271 
6272 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6273 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6274 MODULE_LICENSE("GPL");
6275 MODULE_SOFTDEP("pre: crc32c");
6276 module_init(ext4_init_fs)
6277 module_exit(ext4_exit_fs)
6278