xref: /openbmc/linux/fs/ext4/super.c (revision 11788d9b)
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_lock -> 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_lock
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_lock
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 		panic("EXT4-fs (device %s): panic forced after error\n",
526 			sb->s_id);
527 	}
528 }
529 
530 #define ext4_error_ratelimit(sb)					\
531 		___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),	\
532 			     "EXT4-fs error")
533 
534 void __ext4_error(struct super_block *sb, const char *function,
535 		  unsigned int line, int error, __u64 block,
536 		  const char *fmt, ...)
537 {
538 	struct va_format vaf;
539 	va_list args;
540 
541 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
542 		return;
543 
544 	trace_ext4_error(sb, function, line);
545 	if (ext4_error_ratelimit(sb)) {
546 		va_start(args, fmt);
547 		vaf.fmt = fmt;
548 		vaf.va = &args;
549 		printk(KERN_CRIT
550 		       "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
551 		       sb->s_id, function, line, current->comm, &vaf);
552 		va_end(args);
553 	}
554 	save_error_info(sb, error, 0, block, function, line);
555 	ext4_handle_error(sb);
556 }
557 
558 void __ext4_error_inode(struct inode *inode, const char *function,
559 			unsigned int line, ext4_fsblk_t block, int error,
560 			const char *fmt, ...)
561 {
562 	va_list args;
563 	struct va_format vaf;
564 
565 	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
566 		return;
567 
568 	trace_ext4_error(inode->i_sb, function, line);
569 	if (ext4_error_ratelimit(inode->i_sb)) {
570 		va_start(args, fmt);
571 		vaf.fmt = fmt;
572 		vaf.va = &args;
573 		if (block)
574 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
575 			       "inode #%lu: block %llu: comm %s: %pV\n",
576 			       inode->i_sb->s_id, function, line, inode->i_ino,
577 			       block, current->comm, &vaf);
578 		else
579 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
580 			       "inode #%lu: comm %s: %pV\n",
581 			       inode->i_sb->s_id, function, line, inode->i_ino,
582 			       current->comm, &vaf);
583 		va_end(args);
584 	}
585 	save_error_info(inode->i_sb, error, inode->i_ino, block,
586 			function, line);
587 	ext4_handle_error(inode->i_sb);
588 }
589 
590 void __ext4_error_file(struct file *file, const char *function,
591 		       unsigned int line, ext4_fsblk_t block,
592 		       const char *fmt, ...)
593 {
594 	va_list args;
595 	struct va_format vaf;
596 	struct inode *inode = file_inode(file);
597 	char pathname[80], *path;
598 
599 	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
600 		return;
601 
602 	trace_ext4_error(inode->i_sb, function, line);
603 	if (ext4_error_ratelimit(inode->i_sb)) {
604 		path = file_path(file, pathname, sizeof(pathname));
605 		if (IS_ERR(path))
606 			path = "(unknown)";
607 		va_start(args, fmt);
608 		vaf.fmt = fmt;
609 		vaf.va = &args;
610 		if (block)
611 			printk(KERN_CRIT
612 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
613 			       "block %llu: comm %s: path %s: %pV\n",
614 			       inode->i_sb->s_id, function, line, inode->i_ino,
615 			       block, current->comm, path, &vaf);
616 		else
617 			printk(KERN_CRIT
618 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
619 			       "comm %s: path %s: %pV\n",
620 			       inode->i_sb->s_id, function, line, inode->i_ino,
621 			       current->comm, path, &vaf);
622 		va_end(args);
623 	}
624 	save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
625 			function, line);
626 	ext4_handle_error(inode->i_sb);
627 }
628 
629 const char *ext4_decode_error(struct super_block *sb, int errno,
630 			      char nbuf[16])
631 {
632 	char *errstr = NULL;
633 
634 	switch (errno) {
635 	case -EFSCORRUPTED:
636 		errstr = "Corrupt filesystem";
637 		break;
638 	case -EFSBADCRC:
639 		errstr = "Filesystem failed CRC";
640 		break;
641 	case -EIO:
642 		errstr = "IO failure";
643 		break;
644 	case -ENOMEM:
645 		errstr = "Out of memory";
646 		break;
647 	case -EROFS:
648 		if (!sb || (EXT4_SB(sb)->s_journal &&
649 			    EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
650 			errstr = "Journal has aborted";
651 		else
652 			errstr = "Readonly filesystem";
653 		break;
654 	default:
655 		/* If the caller passed in an extra buffer for unknown
656 		 * errors, textualise them now.  Else we just return
657 		 * NULL. */
658 		if (nbuf) {
659 			/* Check for truncated error codes... */
660 			if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
661 				errstr = nbuf;
662 		}
663 		break;
664 	}
665 
666 	return errstr;
667 }
668 
669 /* __ext4_std_error decodes expected errors from journaling functions
670  * automatically and invokes the appropriate error response.  */
671 
672 void __ext4_std_error(struct super_block *sb, const char *function,
673 		      unsigned int line, int errno)
674 {
675 	char nbuf[16];
676 	const char *errstr;
677 
678 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
679 		return;
680 
681 	/* Special case: if the error is EROFS, and we're not already
682 	 * inside a transaction, then there's really no point in logging
683 	 * an error. */
684 	if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
685 		return;
686 
687 	if (ext4_error_ratelimit(sb)) {
688 		errstr = ext4_decode_error(sb, errno, nbuf);
689 		printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
690 		       sb->s_id, function, line, errstr);
691 	}
692 
693 	save_error_info(sb, -errno, 0, 0, function, line);
694 	ext4_handle_error(sb);
695 }
696 
697 /*
698  * ext4_abort is a much stronger failure handler than ext4_error.  The
699  * abort function may be used to deal with unrecoverable failures such
700  * as journal IO errors or ENOMEM at a critical moment in log management.
701  *
702  * We unconditionally force the filesystem into an ABORT|READONLY state,
703  * unless the error response on the fs has been set to panic in which
704  * case we take the easy way out and panic immediately.
705  */
706 
707 void __ext4_abort(struct super_block *sb, const char *function,
708 		  unsigned int line, int error, const char *fmt, ...)
709 {
710 	struct va_format vaf;
711 	va_list args;
712 
713 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
714 		return;
715 
716 	save_error_info(sb, error, 0, 0, function, line);
717 	va_start(args, fmt);
718 	vaf.fmt = fmt;
719 	vaf.va = &args;
720 	printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
721 	       sb->s_id, function, line, &vaf);
722 	va_end(args);
723 
724 	if (sb_rdonly(sb) == 0) {
725 		EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
726 		if (EXT4_SB(sb)->s_journal)
727 			jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
728 
729 		ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
730 		/*
731 		 * Make sure updated value of ->s_mount_flags will be visible
732 		 * before ->s_flags update
733 		 */
734 		smp_wmb();
735 		sb->s_flags |= SB_RDONLY;
736 	}
737 	if (test_opt(sb, ERRORS_PANIC) && !system_going_down())
738 		panic("EXT4-fs panic from previous error\n");
739 }
740 
741 void __ext4_msg(struct super_block *sb,
742 		const char *prefix, const char *fmt, ...)
743 {
744 	struct va_format vaf;
745 	va_list args;
746 
747 	if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
748 		return;
749 
750 	va_start(args, fmt);
751 	vaf.fmt = fmt;
752 	vaf.va = &args;
753 	printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
754 	va_end(args);
755 }
756 
757 #define ext4_warning_ratelimit(sb)					\
758 		___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),	\
759 			     "EXT4-fs warning")
760 
761 void __ext4_warning(struct super_block *sb, const char *function,
762 		    unsigned int line, const char *fmt, ...)
763 {
764 	struct va_format vaf;
765 	va_list args;
766 
767 	if (!ext4_warning_ratelimit(sb))
768 		return;
769 
770 	va_start(args, fmt);
771 	vaf.fmt = fmt;
772 	vaf.va = &args;
773 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
774 	       sb->s_id, function, line, &vaf);
775 	va_end(args);
776 }
777 
778 void __ext4_warning_inode(const struct inode *inode, const char *function,
779 			  unsigned int line, const char *fmt, ...)
780 {
781 	struct va_format vaf;
782 	va_list args;
783 
784 	if (!ext4_warning_ratelimit(inode->i_sb))
785 		return;
786 
787 	va_start(args, fmt);
788 	vaf.fmt = fmt;
789 	vaf.va = &args;
790 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
791 	       "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
792 	       function, line, inode->i_ino, current->comm, &vaf);
793 	va_end(args);
794 }
795 
796 void __ext4_grp_locked_error(const char *function, unsigned int line,
797 			     struct super_block *sb, ext4_group_t grp,
798 			     unsigned long ino, ext4_fsblk_t block,
799 			     const char *fmt, ...)
800 __releases(bitlock)
801 __acquires(bitlock)
802 {
803 	struct va_format vaf;
804 	va_list args;
805 
806 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
807 		return;
808 
809 	trace_ext4_error(sb, function, line);
810 	__save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
811 
812 	if (ext4_error_ratelimit(sb)) {
813 		va_start(args, fmt);
814 		vaf.fmt = fmt;
815 		vaf.va = &args;
816 		printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
817 		       sb->s_id, function, line, grp);
818 		if (ino)
819 			printk(KERN_CONT "inode %lu: ", ino);
820 		if (block)
821 			printk(KERN_CONT "block %llu:",
822 			       (unsigned long long) block);
823 		printk(KERN_CONT "%pV\n", &vaf);
824 		va_end(args);
825 	}
826 
827 	if (test_opt(sb, WARN_ON_ERROR))
828 		WARN_ON_ONCE(1);
829 
830 	if (test_opt(sb, ERRORS_CONT)) {
831 		ext4_commit_super(sb, 0);
832 		return;
833 	}
834 
835 	ext4_unlock_group(sb, grp);
836 	ext4_commit_super(sb, 1);
837 	ext4_handle_error(sb);
838 	/*
839 	 * We only get here in the ERRORS_RO case; relocking the group
840 	 * may be dangerous, but nothing bad will happen since the
841 	 * filesystem will have already been marked read/only and the
842 	 * journal has been aborted.  We return 1 as a hint to callers
843 	 * who might what to use the return value from
844 	 * ext4_grp_locked_error() to distinguish between the
845 	 * ERRORS_CONT and ERRORS_RO case, and perhaps return more
846 	 * aggressively from the ext4 function in question, with a
847 	 * more appropriate error code.
848 	 */
849 	ext4_lock_group(sb, grp);
850 	return;
851 }
852 
853 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
854 				     ext4_group_t group,
855 				     unsigned int flags)
856 {
857 	struct ext4_sb_info *sbi = EXT4_SB(sb);
858 	struct ext4_group_info *grp = ext4_get_group_info(sb, group);
859 	struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
860 	int ret;
861 
862 	if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
863 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
864 					    &grp->bb_state);
865 		if (!ret)
866 			percpu_counter_sub(&sbi->s_freeclusters_counter,
867 					   grp->bb_free);
868 	}
869 
870 	if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
871 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
872 					    &grp->bb_state);
873 		if (!ret && gdp) {
874 			int count;
875 
876 			count = ext4_free_inodes_count(sb, gdp);
877 			percpu_counter_sub(&sbi->s_freeinodes_counter,
878 					   count);
879 		}
880 	}
881 }
882 
883 void ext4_update_dynamic_rev(struct super_block *sb)
884 {
885 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
886 
887 	if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
888 		return;
889 
890 	ext4_warning(sb,
891 		     "updating to rev %d because of new feature flag, "
892 		     "running e2fsck is recommended",
893 		     EXT4_DYNAMIC_REV);
894 
895 	es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
896 	es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
897 	es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
898 	/* leave es->s_feature_*compat flags alone */
899 	/* es->s_uuid will be set by e2fsck if empty */
900 
901 	/*
902 	 * The rest of the superblock fields should be zero, and if not it
903 	 * means they are likely already in use, so leave them alone.  We
904 	 * can leave it up to e2fsck to clean up any inconsistencies there.
905 	 */
906 }
907 
908 /*
909  * Open the external journal device
910  */
911 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
912 {
913 	struct block_device *bdev;
914 
915 	bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
916 	if (IS_ERR(bdev))
917 		goto fail;
918 	return bdev;
919 
920 fail:
921 	ext4_msg(sb, KERN_ERR,
922 		 "failed to open journal device unknown-block(%u,%u) %ld",
923 		 MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
924 	return NULL;
925 }
926 
927 /*
928  * Release the journal device
929  */
930 static void ext4_blkdev_put(struct block_device *bdev)
931 {
932 	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
933 }
934 
935 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
936 {
937 	struct block_device *bdev;
938 	bdev = sbi->journal_bdev;
939 	if (bdev) {
940 		ext4_blkdev_put(bdev);
941 		sbi->journal_bdev = NULL;
942 	}
943 }
944 
945 static inline struct inode *orphan_list_entry(struct list_head *l)
946 {
947 	return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
948 }
949 
950 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
951 {
952 	struct list_head *l;
953 
954 	ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
955 		 le32_to_cpu(sbi->s_es->s_last_orphan));
956 
957 	printk(KERN_ERR "sb_info orphan list:\n");
958 	list_for_each(l, &sbi->s_orphan) {
959 		struct inode *inode = orphan_list_entry(l);
960 		printk(KERN_ERR "  "
961 		       "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
962 		       inode->i_sb->s_id, inode->i_ino, inode,
963 		       inode->i_mode, inode->i_nlink,
964 		       NEXT_ORPHAN(inode));
965 	}
966 }
967 
968 #ifdef CONFIG_QUOTA
969 static int ext4_quota_off(struct super_block *sb, int type);
970 
971 static inline void ext4_quota_off_umount(struct super_block *sb)
972 {
973 	int type;
974 
975 	/* Use our quota_off function to clear inode flags etc. */
976 	for (type = 0; type < EXT4_MAXQUOTAS; type++)
977 		ext4_quota_off(sb, type);
978 }
979 
980 /*
981  * This is a helper function which is used in the mount/remount
982  * codepaths (which holds s_umount) to fetch the quota file name.
983  */
984 static inline char *get_qf_name(struct super_block *sb,
985 				struct ext4_sb_info *sbi,
986 				int type)
987 {
988 	return rcu_dereference_protected(sbi->s_qf_names[type],
989 					 lockdep_is_held(&sb->s_umount));
990 }
991 #else
992 static inline void ext4_quota_off_umount(struct super_block *sb)
993 {
994 }
995 #endif
996 
997 static void ext4_put_super(struct super_block *sb)
998 {
999 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1000 	struct ext4_super_block *es = sbi->s_es;
1001 	struct buffer_head **group_desc;
1002 	struct flex_groups **flex_groups;
1003 	int aborted = 0;
1004 	int i, err;
1005 
1006 	ext4_unregister_li_request(sb);
1007 	ext4_quota_off_umount(sb);
1008 
1009 	destroy_workqueue(sbi->rsv_conversion_wq);
1010 
1011 	/*
1012 	 * Unregister sysfs before destroying jbd2 journal.
1013 	 * Since we could still access attr_journal_task attribute via sysfs
1014 	 * path which could have sbi->s_journal->j_task as NULL
1015 	 */
1016 	ext4_unregister_sysfs(sb);
1017 
1018 	if (sbi->s_journal) {
1019 		aborted = is_journal_aborted(sbi->s_journal);
1020 		err = jbd2_journal_destroy(sbi->s_journal);
1021 		sbi->s_journal = NULL;
1022 		if ((err < 0) && !aborted) {
1023 			ext4_abort(sb, -err, "Couldn't clean up the journal");
1024 		}
1025 	}
1026 
1027 	ext4_es_unregister_shrinker(sbi);
1028 	del_timer_sync(&sbi->s_err_report);
1029 	ext4_release_system_zone(sb);
1030 	ext4_mb_release(sb);
1031 	ext4_ext_release(sb);
1032 
1033 	if (!sb_rdonly(sb) && !aborted) {
1034 		ext4_clear_feature_journal_needs_recovery(sb);
1035 		es->s_state = cpu_to_le16(sbi->s_mount_state);
1036 	}
1037 	if (!sb_rdonly(sb))
1038 		ext4_commit_super(sb, 1);
1039 
1040 	rcu_read_lock();
1041 	group_desc = rcu_dereference(sbi->s_group_desc);
1042 	for (i = 0; i < sbi->s_gdb_count; i++)
1043 		brelse(group_desc[i]);
1044 	kvfree(group_desc);
1045 	flex_groups = rcu_dereference(sbi->s_flex_groups);
1046 	if (flex_groups) {
1047 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1048 			kvfree(flex_groups[i]);
1049 		kvfree(flex_groups);
1050 	}
1051 	rcu_read_unlock();
1052 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
1053 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
1054 	percpu_counter_destroy(&sbi->s_dirs_counter);
1055 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1056 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
1057 #ifdef CONFIG_QUOTA
1058 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
1059 		kfree(get_qf_name(sb, sbi, i));
1060 #endif
1061 
1062 	/* Debugging code just in case the in-memory inode orphan list
1063 	 * isn't empty.  The on-disk one can be non-empty if we've
1064 	 * detected an error and taken the fs readonly, but the
1065 	 * in-memory list had better be clean by this point. */
1066 	if (!list_empty(&sbi->s_orphan))
1067 		dump_orphan_list(sb, sbi);
1068 	J_ASSERT(list_empty(&sbi->s_orphan));
1069 
1070 	sync_blockdev(sb->s_bdev);
1071 	invalidate_bdev(sb->s_bdev);
1072 	if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1073 		/*
1074 		 * Invalidate the journal device's buffers.  We don't want them
1075 		 * floating about in memory - the physical journal device may
1076 		 * hotswapped, and it breaks the `ro-after' testing code.
1077 		 */
1078 		sync_blockdev(sbi->journal_bdev);
1079 		invalidate_bdev(sbi->journal_bdev);
1080 		ext4_blkdev_remove(sbi);
1081 	}
1082 
1083 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1084 	sbi->s_ea_inode_cache = NULL;
1085 
1086 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1087 	sbi->s_ea_block_cache = NULL;
1088 
1089 	if (sbi->s_mmp_tsk)
1090 		kthread_stop(sbi->s_mmp_tsk);
1091 	brelse(sbi->s_sbh);
1092 	sb->s_fs_info = NULL;
1093 	/*
1094 	 * Now that we are completely done shutting down the
1095 	 * superblock, we need to actually destroy the kobject.
1096 	 */
1097 	kobject_put(&sbi->s_kobj);
1098 	wait_for_completion(&sbi->s_kobj_unregister);
1099 	if (sbi->s_chksum_driver)
1100 		crypto_free_shash(sbi->s_chksum_driver);
1101 	kfree(sbi->s_blockgroup_lock);
1102 	fs_put_dax(sbi->s_daxdev);
1103 	fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
1104 #ifdef CONFIG_UNICODE
1105 	utf8_unload(sbi->s_encoding);
1106 #endif
1107 	kfree(sbi);
1108 }
1109 
1110 static struct kmem_cache *ext4_inode_cachep;
1111 
1112 /*
1113  * Called inside transaction, so use GFP_NOFS
1114  */
1115 static struct inode *ext4_alloc_inode(struct super_block *sb)
1116 {
1117 	struct ext4_inode_info *ei;
1118 
1119 	ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1120 	if (!ei)
1121 		return NULL;
1122 
1123 	inode_set_iversion(&ei->vfs_inode, 1);
1124 	spin_lock_init(&ei->i_raw_lock);
1125 	INIT_LIST_HEAD(&ei->i_prealloc_list);
1126 	spin_lock_init(&ei->i_prealloc_lock);
1127 	ext4_es_init_tree(&ei->i_es_tree);
1128 	rwlock_init(&ei->i_es_lock);
1129 	INIT_LIST_HEAD(&ei->i_es_list);
1130 	ei->i_es_all_nr = 0;
1131 	ei->i_es_shk_nr = 0;
1132 	ei->i_es_shrink_lblk = 0;
1133 	ei->i_reserved_data_blocks = 0;
1134 	spin_lock_init(&(ei->i_block_reservation_lock));
1135 	ext4_init_pending_tree(&ei->i_pending_tree);
1136 #ifdef CONFIG_QUOTA
1137 	ei->i_reserved_quota = 0;
1138 	memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1139 #endif
1140 	ei->jinode = NULL;
1141 	INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1142 	spin_lock_init(&ei->i_completed_io_lock);
1143 	ei->i_sync_tid = 0;
1144 	ei->i_datasync_tid = 0;
1145 	atomic_set(&ei->i_unwritten, 0);
1146 	INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1147 	return &ei->vfs_inode;
1148 }
1149 
1150 static int ext4_drop_inode(struct inode *inode)
1151 {
1152 	int drop = generic_drop_inode(inode);
1153 
1154 	if (!drop)
1155 		drop = fscrypt_drop_inode(inode);
1156 
1157 	trace_ext4_drop_inode(inode, drop);
1158 	return drop;
1159 }
1160 
1161 static void ext4_free_in_core_inode(struct inode *inode)
1162 {
1163 	fscrypt_free_inode(inode);
1164 	kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1165 }
1166 
1167 static void ext4_destroy_inode(struct inode *inode)
1168 {
1169 	if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1170 		ext4_msg(inode->i_sb, KERN_ERR,
1171 			 "Inode %lu (%p): orphan list check failed!",
1172 			 inode->i_ino, EXT4_I(inode));
1173 		print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1174 				EXT4_I(inode), sizeof(struct ext4_inode_info),
1175 				true);
1176 		dump_stack();
1177 	}
1178 }
1179 
1180 static void init_once(void *foo)
1181 {
1182 	struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1183 
1184 	INIT_LIST_HEAD(&ei->i_orphan);
1185 	init_rwsem(&ei->xattr_sem);
1186 	init_rwsem(&ei->i_data_sem);
1187 	init_rwsem(&ei->i_mmap_sem);
1188 	inode_init_once(&ei->vfs_inode);
1189 }
1190 
1191 static int __init init_inodecache(void)
1192 {
1193 	ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1194 				sizeof(struct ext4_inode_info), 0,
1195 				(SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1196 					SLAB_ACCOUNT),
1197 				offsetof(struct ext4_inode_info, i_data),
1198 				sizeof_field(struct ext4_inode_info, i_data),
1199 				init_once);
1200 	if (ext4_inode_cachep == NULL)
1201 		return -ENOMEM;
1202 	return 0;
1203 }
1204 
1205 static void destroy_inodecache(void)
1206 {
1207 	/*
1208 	 * Make sure all delayed rcu free inodes are flushed before we
1209 	 * destroy cache.
1210 	 */
1211 	rcu_barrier();
1212 	kmem_cache_destroy(ext4_inode_cachep);
1213 }
1214 
1215 void ext4_clear_inode(struct inode *inode)
1216 {
1217 	invalidate_inode_buffers(inode);
1218 	clear_inode(inode);
1219 	ext4_discard_preallocations(inode);
1220 	ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1221 	dquot_drop(inode);
1222 	if (EXT4_I(inode)->jinode) {
1223 		jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1224 					       EXT4_I(inode)->jinode);
1225 		jbd2_free_inode(EXT4_I(inode)->jinode);
1226 		EXT4_I(inode)->jinode = NULL;
1227 	}
1228 	fscrypt_put_encryption_info(inode);
1229 	fsverity_cleanup_inode(inode);
1230 }
1231 
1232 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1233 					u64 ino, u32 generation)
1234 {
1235 	struct inode *inode;
1236 
1237 	/*
1238 	 * Currently we don't know the generation for parent directory, so
1239 	 * a generation of 0 means "accept any"
1240 	 */
1241 	inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1242 	if (IS_ERR(inode))
1243 		return ERR_CAST(inode);
1244 	if (generation && inode->i_generation != generation) {
1245 		iput(inode);
1246 		return ERR_PTR(-ESTALE);
1247 	}
1248 
1249 	return inode;
1250 }
1251 
1252 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1253 					int fh_len, int fh_type)
1254 {
1255 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1256 				    ext4_nfs_get_inode);
1257 }
1258 
1259 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1260 					int fh_len, int fh_type)
1261 {
1262 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1263 				    ext4_nfs_get_inode);
1264 }
1265 
1266 static int ext4_nfs_commit_metadata(struct inode *inode)
1267 {
1268 	struct writeback_control wbc = {
1269 		.sync_mode = WB_SYNC_ALL
1270 	};
1271 
1272 	trace_ext4_nfs_commit_metadata(inode);
1273 	return ext4_write_inode(inode, &wbc);
1274 }
1275 
1276 /*
1277  * Try to release metadata pages (indirect blocks, directories) which are
1278  * mapped via the block device.  Since these pages could have journal heads
1279  * which would prevent try_to_free_buffers() from freeing them, we must use
1280  * jbd2 layer's try_to_free_buffers() function to release them.
1281  */
1282 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1283 				 gfp_t wait)
1284 {
1285 	journal_t *journal = EXT4_SB(sb)->s_journal;
1286 
1287 	WARN_ON(PageChecked(page));
1288 	if (!page_has_buffers(page))
1289 		return 0;
1290 	if (journal)
1291 		return jbd2_journal_try_to_free_buffers(journal, page,
1292 						wait & ~__GFP_DIRECT_RECLAIM);
1293 	return try_to_free_buffers(page);
1294 }
1295 
1296 #ifdef CONFIG_FS_ENCRYPTION
1297 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1298 {
1299 	return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1300 				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1301 }
1302 
1303 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1304 							void *fs_data)
1305 {
1306 	handle_t *handle = fs_data;
1307 	int res, res2, credits, retries = 0;
1308 
1309 	/*
1310 	 * Encrypting the root directory is not allowed because e2fsck expects
1311 	 * lost+found to exist and be unencrypted, and encrypting the root
1312 	 * directory would imply encrypting the lost+found directory as well as
1313 	 * the filename "lost+found" itself.
1314 	 */
1315 	if (inode->i_ino == EXT4_ROOT_INO)
1316 		return -EPERM;
1317 
1318 	if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1319 		return -EINVAL;
1320 
1321 	if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1322 		return -EOPNOTSUPP;
1323 
1324 	res = ext4_convert_inline_data(inode);
1325 	if (res)
1326 		return res;
1327 
1328 	/*
1329 	 * If a journal handle was specified, then the encryption context is
1330 	 * being set on a new inode via inheritance and is part of a larger
1331 	 * transaction to create the inode.  Otherwise the encryption context is
1332 	 * being set on an existing inode in its own transaction.  Only in the
1333 	 * latter case should the "retry on ENOSPC" logic be used.
1334 	 */
1335 
1336 	if (handle) {
1337 		res = ext4_xattr_set_handle(handle, inode,
1338 					    EXT4_XATTR_INDEX_ENCRYPTION,
1339 					    EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1340 					    ctx, len, 0);
1341 		if (!res) {
1342 			ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1343 			ext4_clear_inode_state(inode,
1344 					EXT4_STATE_MAY_INLINE_DATA);
1345 			/*
1346 			 * Update inode->i_flags - S_ENCRYPTED will be enabled,
1347 			 * S_DAX may be disabled
1348 			 */
1349 			ext4_set_inode_flags(inode, false);
1350 		}
1351 		return res;
1352 	}
1353 
1354 	res = dquot_initialize(inode);
1355 	if (res)
1356 		return res;
1357 retry:
1358 	res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1359 				     &credits);
1360 	if (res)
1361 		return res;
1362 
1363 	handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1364 	if (IS_ERR(handle))
1365 		return PTR_ERR(handle);
1366 
1367 	res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1368 				    EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1369 				    ctx, len, 0);
1370 	if (!res) {
1371 		ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1372 		/*
1373 		 * Update inode->i_flags - S_ENCRYPTED will be enabled,
1374 		 * S_DAX may be disabled
1375 		 */
1376 		ext4_set_inode_flags(inode, false);
1377 		res = ext4_mark_inode_dirty(handle, inode);
1378 		if (res)
1379 			EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1380 	}
1381 	res2 = ext4_journal_stop(handle);
1382 
1383 	if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1384 		goto retry;
1385 	if (!res)
1386 		res = res2;
1387 	return res;
1388 }
1389 
1390 static const union fscrypt_context *
1391 ext4_get_dummy_context(struct super_block *sb)
1392 {
1393 	return EXT4_SB(sb)->s_dummy_enc_ctx.ctx;
1394 }
1395 
1396 static bool ext4_has_stable_inodes(struct super_block *sb)
1397 {
1398 	return ext4_has_feature_stable_inodes(sb);
1399 }
1400 
1401 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1402 				       int *ino_bits_ret, int *lblk_bits_ret)
1403 {
1404 	*ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1405 	*lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1406 }
1407 
1408 static const struct fscrypt_operations ext4_cryptops = {
1409 	.key_prefix		= "ext4:",
1410 	.get_context		= ext4_get_context,
1411 	.set_context		= ext4_set_context,
1412 	.get_dummy_context	= ext4_get_dummy_context,
1413 	.empty_dir		= ext4_empty_dir,
1414 	.max_namelen		= EXT4_NAME_LEN,
1415 	.has_stable_inodes	= ext4_has_stable_inodes,
1416 	.get_ino_and_lblk_bits	= ext4_get_ino_and_lblk_bits,
1417 };
1418 #endif
1419 
1420 #ifdef CONFIG_QUOTA
1421 static const char * const quotatypes[] = INITQFNAMES;
1422 #define QTYPE2NAME(t) (quotatypes[t])
1423 
1424 static int ext4_write_dquot(struct dquot *dquot);
1425 static int ext4_acquire_dquot(struct dquot *dquot);
1426 static int ext4_release_dquot(struct dquot *dquot);
1427 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1428 static int ext4_write_info(struct super_block *sb, int type);
1429 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1430 			 const struct path *path);
1431 static int ext4_quota_on_mount(struct super_block *sb, int type);
1432 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1433 			       size_t len, loff_t off);
1434 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1435 				const char *data, size_t len, loff_t off);
1436 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1437 			     unsigned int flags);
1438 static int ext4_enable_quotas(struct super_block *sb);
1439 
1440 static struct dquot **ext4_get_dquots(struct inode *inode)
1441 {
1442 	return EXT4_I(inode)->i_dquot;
1443 }
1444 
1445 static const struct dquot_operations ext4_quota_operations = {
1446 	.get_reserved_space	= ext4_get_reserved_space,
1447 	.write_dquot		= ext4_write_dquot,
1448 	.acquire_dquot		= ext4_acquire_dquot,
1449 	.release_dquot		= ext4_release_dquot,
1450 	.mark_dirty		= ext4_mark_dquot_dirty,
1451 	.write_info		= ext4_write_info,
1452 	.alloc_dquot		= dquot_alloc,
1453 	.destroy_dquot		= dquot_destroy,
1454 	.get_projid		= ext4_get_projid,
1455 	.get_inode_usage	= ext4_get_inode_usage,
1456 	.get_next_id		= dquot_get_next_id,
1457 };
1458 
1459 static const struct quotactl_ops ext4_qctl_operations = {
1460 	.quota_on	= ext4_quota_on,
1461 	.quota_off	= ext4_quota_off,
1462 	.quota_sync	= dquot_quota_sync,
1463 	.get_state	= dquot_get_state,
1464 	.set_info	= dquot_set_dqinfo,
1465 	.get_dqblk	= dquot_get_dqblk,
1466 	.set_dqblk	= dquot_set_dqblk,
1467 	.get_nextdqblk	= dquot_get_next_dqblk,
1468 };
1469 #endif
1470 
1471 static const struct super_operations ext4_sops = {
1472 	.alloc_inode	= ext4_alloc_inode,
1473 	.free_inode	= ext4_free_in_core_inode,
1474 	.destroy_inode	= ext4_destroy_inode,
1475 	.write_inode	= ext4_write_inode,
1476 	.dirty_inode	= ext4_dirty_inode,
1477 	.drop_inode	= ext4_drop_inode,
1478 	.evict_inode	= ext4_evict_inode,
1479 	.put_super	= ext4_put_super,
1480 	.sync_fs	= ext4_sync_fs,
1481 	.freeze_fs	= ext4_freeze,
1482 	.unfreeze_fs	= ext4_unfreeze,
1483 	.statfs		= ext4_statfs,
1484 	.remount_fs	= ext4_remount,
1485 	.show_options	= ext4_show_options,
1486 #ifdef CONFIG_QUOTA
1487 	.quota_read	= ext4_quota_read,
1488 	.quota_write	= ext4_quota_write,
1489 	.get_dquots	= ext4_get_dquots,
1490 #endif
1491 	.bdev_try_to_free_page = bdev_try_to_free_page,
1492 };
1493 
1494 static const struct export_operations ext4_export_ops = {
1495 	.fh_to_dentry = ext4_fh_to_dentry,
1496 	.fh_to_parent = ext4_fh_to_parent,
1497 	.get_parent = ext4_get_parent,
1498 	.commit_metadata = ext4_nfs_commit_metadata,
1499 };
1500 
1501 enum {
1502 	Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1503 	Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1504 	Opt_nouid32, Opt_debug, Opt_removed,
1505 	Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1506 	Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1507 	Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1508 	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1509 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1510 	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1511 	Opt_inlinecrypt,
1512 	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1513 	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1514 	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1515 	Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1516 	Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1517 	Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1518 	Opt_nowarn_on_error, Opt_mblk_io_submit,
1519 	Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1520 	Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1521 	Opt_inode_readahead_blks, Opt_journal_ioprio,
1522 	Opt_dioread_nolock, Opt_dioread_lock,
1523 	Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1524 	Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1525 };
1526 
1527 static const match_table_t tokens = {
1528 	{Opt_bsd_df, "bsddf"},
1529 	{Opt_minix_df, "minixdf"},
1530 	{Opt_grpid, "grpid"},
1531 	{Opt_grpid, "bsdgroups"},
1532 	{Opt_nogrpid, "nogrpid"},
1533 	{Opt_nogrpid, "sysvgroups"},
1534 	{Opt_resgid, "resgid=%u"},
1535 	{Opt_resuid, "resuid=%u"},
1536 	{Opt_sb, "sb=%u"},
1537 	{Opt_err_cont, "errors=continue"},
1538 	{Opt_err_panic, "errors=panic"},
1539 	{Opt_err_ro, "errors=remount-ro"},
1540 	{Opt_nouid32, "nouid32"},
1541 	{Opt_debug, "debug"},
1542 	{Opt_removed, "oldalloc"},
1543 	{Opt_removed, "orlov"},
1544 	{Opt_user_xattr, "user_xattr"},
1545 	{Opt_nouser_xattr, "nouser_xattr"},
1546 	{Opt_acl, "acl"},
1547 	{Opt_noacl, "noacl"},
1548 	{Opt_noload, "norecovery"},
1549 	{Opt_noload, "noload"},
1550 	{Opt_removed, "nobh"},
1551 	{Opt_removed, "bh"},
1552 	{Opt_commit, "commit=%u"},
1553 	{Opt_min_batch_time, "min_batch_time=%u"},
1554 	{Opt_max_batch_time, "max_batch_time=%u"},
1555 	{Opt_journal_dev, "journal_dev=%u"},
1556 	{Opt_journal_path, "journal_path=%s"},
1557 	{Opt_journal_checksum, "journal_checksum"},
1558 	{Opt_nojournal_checksum, "nojournal_checksum"},
1559 	{Opt_journal_async_commit, "journal_async_commit"},
1560 	{Opt_abort, "abort"},
1561 	{Opt_data_journal, "data=journal"},
1562 	{Opt_data_ordered, "data=ordered"},
1563 	{Opt_data_writeback, "data=writeback"},
1564 	{Opt_data_err_abort, "data_err=abort"},
1565 	{Opt_data_err_ignore, "data_err=ignore"},
1566 	{Opt_offusrjquota, "usrjquota="},
1567 	{Opt_usrjquota, "usrjquota=%s"},
1568 	{Opt_offgrpjquota, "grpjquota="},
1569 	{Opt_grpjquota, "grpjquota=%s"},
1570 	{Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1571 	{Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1572 	{Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1573 	{Opt_grpquota, "grpquota"},
1574 	{Opt_noquota, "noquota"},
1575 	{Opt_quota, "quota"},
1576 	{Opt_usrquota, "usrquota"},
1577 	{Opt_prjquota, "prjquota"},
1578 	{Opt_barrier, "barrier=%u"},
1579 	{Opt_barrier, "barrier"},
1580 	{Opt_nobarrier, "nobarrier"},
1581 	{Opt_i_version, "i_version"},
1582 	{Opt_dax, "dax"},
1583 	{Opt_dax_always, "dax=always"},
1584 	{Opt_dax_inode, "dax=inode"},
1585 	{Opt_dax_never, "dax=never"},
1586 	{Opt_stripe, "stripe=%u"},
1587 	{Opt_delalloc, "delalloc"},
1588 	{Opt_warn_on_error, "warn_on_error"},
1589 	{Opt_nowarn_on_error, "nowarn_on_error"},
1590 	{Opt_lazytime, "lazytime"},
1591 	{Opt_nolazytime, "nolazytime"},
1592 	{Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1593 	{Opt_nodelalloc, "nodelalloc"},
1594 	{Opt_removed, "mblk_io_submit"},
1595 	{Opt_removed, "nomblk_io_submit"},
1596 	{Opt_block_validity, "block_validity"},
1597 	{Opt_noblock_validity, "noblock_validity"},
1598 	{Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1599 	{Opt_journal_ioprio, "journal_ioprio=%u"},
1600 	{Opt_auto_da_alloc, "auto_da_alloc=%u"},
1601 	{Opt_auto_da_alloc, "auto_da_alloc"},
1602 	{Opt_noauto_da_alloc, "noauto_da_alloc"},
1603 	{Opt_dioread_nolock, "dioread_nolock"},
1604 	{Opt_dioread_lock, "nodioread_nolock"},
1605 	{Opt_dioread_lock, "dioread_lock"},
1606 	{Opt_discard, "discard"},
1607 	{Opt_nodiscard, "nodiscard"},
1608 	{Opt_init_itable, "init_itable=%u"},
1609 	{Opt_init_itable, "init_itable"},
1610 	{Opt_noinit_itable, "noinit_itable"},
1611 	{Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1612 	{Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1613 	{Opt_test_dummy_encryption, "test_dummy_encryption"},
1614 	{Opt_inlinecrypt, "inlinecrypt"},
1615 	{Opt_nombcache, "nombcache"},
1616 	{Opt_nombcache, "no_mbcache"},	/* for backward compatibility */
1617 	{Opt_removed, "check=none"},	/* mount option from ext2/3 */
1618 	{Opt_removed, "nocheck"},	/* mount option from ext2/3 */
1619 	{Opt_removed, "reservation"},	/* mount option from ext2/3 */
1620 	{Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1621 	{Opt_removed, "journal=%u"},	/* mount option from ext2/3 */
1622 	{Opt_err, NULL},
1623 };
1624 
1625 static ext4_fsblk_t get_sb_block(void **data)
1626 {
1627 	ext4_fsblk_t	sb_block;
1628 	char		*options = (char *) *data;
1629 
1630 	if (!options || strncmp(options, "sb=", 3) != 0)
1631 		return 1;	/* Default location */
1632 
1633 	options += 3;
1634 	/* TODO: use simple_strtoll with >32bit ext4 */
1635 	sb_block = simple_strtoul(options, &options, 0);
1636 	if (*options && *options != ',') {
1637 		printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1638 		       (char *) *data);
1639 		return 1;
1640 	}
1641 	if (*options == ',')
1642 		options++;
1643 	*data = (void *) options;
1644 
1645 	return sb_block;
1646 }
1647 
1648 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1649 static const char deprecated_msg[] =
1650 	"Mount option \"%s\" will be removed by %s\n"
1651 	"Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1652 
1653 #ifdef CONFIG_QUOTA
1654 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1655 {
1656 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1657 	char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1658 	int ret = -1;
1659 
1660 	if (sb_any_quota_loaded(sb) && !old_qname) {
1661 		ext4_msg(sb, KERN_ERR,
1662 			"Cannot change journaled "
1663 			"quota options when quota turned on");
1664 		return -1;
1665 	}
1666 	if (ext4_has_feature_quota(sb)) {
1667 		ext4_msg(sb, KERN_INFO, "Journaled quota options "
1668 			 "ignored when QUOTA feature is enabled");
1669 		return 1;
1670 	}
1671 	qname = match_strdup(args);
1672 	if (!qname) {
1673 		ext4_msg(sb, KERN_ERR,
1674 			"Not enough memory for storing quotafile name");
1675 		return -1;
1676 	}
1677 	if (old_qname) {
1678 		if (strcmp(old_qname, qname) == 0)
1679 			ret = 1;
1680 		else
1681 			ext4_msg(sb, KERN_ERR,
1682 				 "%s quota file already specified",
1683 				 QTYPE2NAME(qtype));
1684 		goto errout;
1685 	}
1686 	if (strchr(qname, '/')) {
1687 		ext4_msg(sb, KERN_ERR,
1688 			"quotafile must be on filesystem root");
1689 		goto errout;
1690 	}
1691 	rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1692 	set_opt(sb, QUOTA);
1693 	return 1;
1694 errout:
1695 	kfree(qname);
1696 	return ret;
1697 }
1698 
1699 static int clear_qf_name(struct super_block *sb, int qtype)
1700 {
1701 
1702 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1703 	char *old_qname = get_qf_name(sb, sbi, qtype);
1704 
1705 	if (sb_any_quota_loaded(sb) && old_qname) {
1706 		ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1707 			" when quota turned on");
1708 		return -1;
1709 	}
1710 	rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1711 	synchronize_rcu();
1712 	kfree(old_qname);
1713 	return 1;
1714 }
1715 #endif
1716 
1717 #define MOPT_SET	0x0001
1718 #define MOPT_CLEAR	0x0002
1719 #define MOPT_NOSUPPORT	0x0004
1720 #define MOPT_EXPLICIT	0x0008
1721 #define MOPT_CLEAR_ERR	0x0010
1722 #define MOPT_GTE0	0x0020
1723 #ifdef CONFIG_QUOTA
1724 #define MOPT_Q		0
1725 #define MOPT_QFMT	0x0040
1726 #else
1727 #define MOPT_Q		MOPT_NOSUPPORT
1728 #define MOPT_QFMT	MOPT_NOSUPPORT
1729 #endif
1730 #define MOPT_DATAJ	0x0080
1731 #define MOPT_NO_EXT2	0x0100
1732 #define MOPT_NO_EXT3	0x0200
1733 #define MOPT_EXT4_ONLY	(MOPT_NO_EXT2 | MOPT_NO_EXT3)
1734 #define MOPT_STRING	0x0400
1735 #define MOPT_SKIP	0x0800
1736 
1737 static const struct mount_opts {
1738 	int	token;
1739 	int	mount_opt;
1740 	int	flags;
1741 } ext4_mount_opts[] = {
1742 	{Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1743 	{Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1744 	{Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1745 	{Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1746 	{Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1747 	{Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1748 	{Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1749 	 MOPT_EXT4_ONLY | MOPT_SET},
1750 	{Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1751 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1752 	{Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1753 	{Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1754 	{Opt_delalloc, EXT4_MOUNT_DELALLOC,
1755 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1756 	{Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1757 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1758 	{Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1759 	{Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1760 	{Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1761 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1762 	{Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1763 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1764 	{Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1765 				    EXT4_MOUNT_JOURNAL_CHECKSUM),
1766 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1767 	{Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1768 	{Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1769 	{Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1770 	{Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1771 	{Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1772 	 MOPT_NO_EXT2},
1773 	{Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1774 	 MOPT_NO_EXT2},
1775 	{Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1776 	{Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1777 	{Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1778 	{Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1779 	{Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1780 	{Opt_commit, 0, MOPT_GTE0},
1781 	{Opt_max_batch_time, 0, MOPT_GTE0},
1782 	{Opt_min_batch_time, 0, MOPT_GTE0},
1783 	{Opt_inode_readahead_blks, 0, MOPT_GTE0},
1784 	{Opt_init_itable, 0, MOPT_GTE0},
1785 	{Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1786 	{Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1787 		MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1788 	{Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1789 		MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1790 	{Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1791 		MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1792 	{Opt_stripe, 0, MOPT_GTE0},
1793 	{Opt_resuid, 0, MOPT_GTE0},
1794 	{Opt_resgid, 0, MOPT_GTE0},
1795 	{Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1796 	{Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1797 	{Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1798 	{Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1799 	{Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1800 	{Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1801 	 MOPT_NO_EXT2 | MOPT_DATAJ},
1802 	{Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1803 	{Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1804 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1805 	{Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1806 	{Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1807 #else
1808 	{Opt_acl, 0, MOPT_NOSUPPORT},
1809 	{Opt_noacl, 0, MOPT_NOSUPPORT},
1810 #endif
1811 	{Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1812 	{Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1813 	{Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1814 	{Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1815 	{Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1816 							MOPT_SET | MOPT_Q},
1817 	{Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1818 							MOPT_SET | MOPT_Q},
1819 	{Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1820 							MOPT_SET | MOPT_Q},
1821 	{Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1822 		       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1823 							MOPT_CLEAR | MOPT_Q},
1824 	{Opt_usrjquota, 0, MOPT_Q},
1825 	{Opt_grpjquota, 0, MOPT_Q},
1826 	{Opt_offusrjquota, 0, MOPT_Q},
1827 	{Opt_offgrpjquota, 0, MOPT_Q},
1828 	{Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1829 	{Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1830 	{Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1831 	{Opt_max_dir_size_kb, 0, MOPT_GTE0},
1832 	{Opt_test_dummy_encryption, 0, MOPT_STRING},
1833 	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1834 	{Opt_err, 0, 0}
1835 };
1836 
1837 #ifdef CONFIG_UNICODE
1838 static const struct ext4_sb_encodings {
1839 	__u16 magic;
1840 	char *name;
1841 	char *version;
1842 } ext4_sb_encoding_map[] = {
1843 	{EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1844 };
1845 
1846 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1847 				 const struct ext4_sb_encodings **encoding,
1848 				 __u16 *flags)
1849 {
1850 	__u16 magic = le16_to_cpu(es->s_encoding);
1851 	int i;
1852 
1853 	for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1854 		if (magic == ext4_sb_encoding_map[i].magic)
1855 			break;
1856 
1857 	if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1858 		return -EINVAL;
1859 
1860 	*encoding = &ext4_sb_encoding_map[i];
1861 	*flags = le16_to_cpu(es->s_encoding_flags);
1862 
1863 	return 0;
1864 }
1865 #endif
1866 
1867 static int ext4_set_test_dummy_encryption(struct super_block *sb,
1868 					  const char *opt,
1869 					  const substring_t *arg,
1870 					  bool is_remount)
1871 {
1872 #ifdef CONFIG_FS_ENCRYPTION
1873 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1874 	int err;
1875 
1876 	/*
1877 	 * This mount option is just for testing, and it's not worthwhile to
1878 	 * implement the extra complexity (e.g. RCU protection) that would be
1879 	 * needed to allow it to be set or changed during remount.  We do allow
1880 	 * it to be specified during remount, but only if there is no change.
1881 	 */
1882 	if (is_remount && !sbi->s_dummy_enc_ctx.ctx) {
1883 		ext4_msg(sb, KERN_WARNING,
1884 			 "Can't set test_dummy_encryption on remount");
1885 		return -1;
1886 	}
1887 	err = fscrypt_set_test_dummy_encryption(sb, arg, &sbi->s_dummy_enc_ctx);
1888 	if (err) {
1889 		if (err == -EEXIST)
1890 			ext4_msg(sb, KERN_WARNING,
1891 				 "Can't change test_dummy_encryption on remount");
1892 		else if (err == -EINVAL)
1893 			ext4_msg(sb, KERN_WARNING,
1894 				 "Value of option \"%s\" is unrecognized", opt);
1895 		else
1896 			ext4_msg(sb, KERN_WARNING,
1897 				 "Error processing option \"%s\" [%d]",
1898 				 opt, err);
1899 		return -1;
1900 	}
1901 	ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
1902 #else
1903 	ext4_msg(sb, KERN_WARNING,
1904 		 "Test dummy encryption mount option ignored");
1905 #endif
1906 	return 1;
1907 }
1908 
1909 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1910 			    substring_t *args, unsigned long *journal_devnum,
1911 			    unsigned int *journal_ioprio, int is_remount)
1912 {
1913 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1914 	const struct mount_opts *m;
1915 	kuid_t uid;
1916 	kgid_t gid;
1917 	int arg = 0;
1918 
1919 #ifdef CONFIG_QUOTA
1920 	if (token == Opt_usrjquota)
1921 		return set_qf_name(sb, USRQUOTA, &args[0]);
1922 	else if (token == Opt_grpjquota)
1923 		return set_qf_name(sb, GRPQUOTA, &args[0]);
1924 	else if (token == Opt_offusrjquota)
1925 		return clear_qf_name(sb, USRQUOTA);
1926 	else if (token == Opt_offgrpjquota)
1927 		return clear_qf_name(sb, GRPQUOTA);
1928 #endif
1929 	switch (token) {
1930 	case Opt_noacl:
1931 	case Opt_nouser_xattr:
1932 		ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1933 		break;
1934 	case Opt_sb:
1935 		return 1;	/* handled by get_sb_block() */
1936 	case Opt_removed:
1937 		ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1938 		return 1;
1939 	case Opt_abort:
1940 		sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1941 		return 1;
1942 	case Opt_i_version:
1943 		sb->s_flags |= SB_I_VERSION;
1944 		return 1;
1945 	case Opt_lazytime:
1946 		sb->s_flags |= SB_LAZYTIME;
1947 		return 1;
1948 	case Opt_nolazytime:
1949 		sb->s_flags &= ~SB_LAZYTIME;
1950 		return 1;
1951 	case Opt_inlinecrypt:
1952 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
1953 		sb->s_flags |= SB_INLINECRYPT;
1954 #else
1955 		ext4_msg(sb, KERN_ERR, "inline encryption not supported");
1956 #endif
1957 		return 1;
1958 	}
1959 
1960 	for (m = ext4_mount_opts; m->token != Opt_err; m++)
1961 		if (token == m->token)
1962 			break;
1963 
1964 	if (m->token == Opt_err) {
1965 		ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1966 			 "or missing value", opt);
1967 		return -1;
1968 	}
1969 
1970 	if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1971 		ext4_msg(sb, KERN_ERR,
1972 			 "Mount option \"%s\" incompatible with ext2", opt);
1973 		return -1;
1974 	}
1975 	if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1976 		ext4_msg(sb, KERN_ERR,
1977 			 "Mount option \"%s\" incompatible with ext3", opt);
1978 		return -1;
1979 	}
1980 
1981 	if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1982 		return -1;
1983 	if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1984 		return -1;
1985 	if (m->flags & MOPT_EXPLICIT) {
1986 		if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1987 			set_opt2(sb, EXPLICIT_DELALLOC);
1988 		} else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1989 			set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1990 		} else
1991 			return -1;
1992 	}
1993 	if (m->flags & MOPT_CLEAR_ERR)
1994 		clear_opt(sb, ERRORS_MASK);
1995 	if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1996 		ext4_msg(sb, KERN_ERR, "Cannot change quota "
1997 			 "options when quota turned on");
1998 		return -1;
1999 	}
2000 
2001 	if (m->flags & MOPT_NOSUPPORT) {
2002 		ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2003 	} else if (token == Opt_commit) {
2004 		if (arg == 0)
2005 			arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2006 		else if (arg > INT_MAX / HZ) {
2007 			ext4_msg(sb, KERN_ERR,
2008 				 "Invalid commit interval %d, "
2009 				 "must be smaller than %d",
2010 				 arg, INT_MAX / HZ);
2011 			return -1;
2012 		}
2013 		sbi->s_commit_interval = HZ * arg;
2014 	} else if (token == Opt_debug_want_extra_isize) {
2015 		if ((arg & 1) ||
2016 		    (arg < 4) ||
2017 		    (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2018 			ext4_msg(sb, KERN_ERR,
2019 				 "Invalid want_extra_isize %d", arg);
2020 			return -1;
2021 		}
2022 		sbi->s_want_extra_isize = arg;
2023 	} else if (token == Opt_max_batch_time) {
2024 		sbi->s_max_batch_time = arg;
2025 	} else if (token == Opt_min_batch_time) {
2026 		sbi->s_min_batch_time = arg;
2027 	} else if (token == Opt_inode_readahead_blks) {
2028 		if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2029 			ext4_msg(sb, KERN_ERR,
2030 				 "EXT4-fs: inode_readahead_blks must be "
2031 				 "0 or a power of 2 smaller than 2^31");
2032 			return -1;
2033 		}
2034 		sbi->s_inode_readahead_blks = arg;
2035 	} else if (token == Opt_init_itable) {
2036 		set_opt(sb, INIT_INODE_TABLE);
2037 		if (!args->from)
2038 			arg = EXT4_DEF_LI_WAIT_MULT;
2039 		sbi->s_li_wait_mult = arg;
2040 	} else if (token == Opt_max_dir_size_kb) {
2041 		sbi->s_max_dir_size_kb = arg;
2042 	} else if (token == Opt_stripe) {
2043 		sbi->s_stripe = arg;
2044 	} else if (token == Opt_resuid) {
2045 		uid = make_kuid(current_user_ns(), arg);
2046 		if (!uid_valid(uid)) {
2047 			ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2048 			return -1;
2049 		}
2050 		sbi->s_resuid = uid;
2051 	} else if (token == Opt_resgid) {
2052 		gid = make_kgid(current_user_ns(), arg);
2053 		if (!gid_valid(gid)) {
2054 			ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2055 			return -1;
2056 		}
2057 		sbi->s_resgid = gid;
2058 	} else if (token == Opt_journal_dev) {
2059 		if (is_remount) {
2060 			ext4_msg(sb, KERN_ERR,
2061 				 "Cannot specify journal on remount");
2062 			return -1;
2063 		}
2064 		*journal_devnum = arg;
2065 	} else if (token == Opt_journal_path) {
2066 		char *journal_path;
2067 		struct inode *journal_inode;
2068 		struct path path;
2069 		int error;
2070 
2071 		if (is_remount) {
2072 			ext4_msg(sb, KERN_ERR,
2073 				 "Cannot specify journal on remount");
2074 			return -1;
2075 		}
2076 		journal_path = match_strdup(&args[0]);
2077 		if (!journal_path) {
2078 			ext4_msg(sb, KERN_ERR, "error: could not dup "
2079 				"journal device string");
2080 			return -1;
2081 		}
2082 
2083 		error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2084 		if (error) {
2085 			ext4_msg(sb, KERN_ERR, "error: could not find "
2086 				"journal device path: error %d", error);
2087 			kfree(journal_path);
2088 			return -1;
2089 		}
2090 
2091 		journal_inode = d_inode(path.dentry);
2092 		if (!S_ISBLK(journal_inode->i_mode)) {
2093 			ext4_msg(sb, KERN_ERR, "error: journal path %s "
2094 				"is not a block device", journal_path);
2095 			path_put(&path);
2096 			kfree(journal_path);
2097 			return -1;
2098 		}
2099 
2100 		*journal_devnum = new_encode_dev(journal_inode->i_rdev);
2101 		path_put(&path);
2102 		kfree(journal_path);
2103 	} else if (token == Opt_journal_ioprio) {
2104 		if (arg > 7) {
2105 			ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2106 				 " (must be 0-7)");
2107 			return -1;
2108 		}
2109 		*journal_ioprio =
2110 			IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2111 	} else if (token == Opt_test_dummy_encryption) {
2112 		return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2113 						      is_remount);
2114 	} else if (m->flags & MOPT_DATAJ) {
2115 		if (is_remount) {
2116 			if (!sbi->s_journal)
2117 				ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2118 			else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2119 				ext4_msg(sb, KERN_ERR,
2120 					 "Cannot change data mode on remount");
2121 				return -1;
2122 			}
2123 		} else {
2124 			clear_opt(sb, DATA_FLAGS);
2125 			sbi->s_mount_opt |= m->mount_opt;
2126 		}
2127 #ifdef CONFIG_QUOTA
2128 	} else if (m->flags & MOPT_QFMT) {
2129 		if (sb_any_quota_loaded(sb) &&
2130 		    sbi->s_jquota_fmt != m->mount_opt) {
2131 			ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2132 				 "quota options when quota turned on");
2133 			return -1;
2134 		}
2135 		if (ext4_has_feature_quota(sb)) {
2136 			ext4_msg(sb, KERN_INFO,
2137 				 "Quota format mount options ignored "
2138 				 "when QUOTA feature is enabled");
2139 			return 1;
2140 		}
2141 		sbi->s_jquota_fmt = m->mount_opt;
2142 #endif
2143 	} else if (token == Opt_dax || token == Opt_dax_always ||
2144 		   token == Opt_dax_inode || token == Opt_dax_never) {
2145 #ifdef CONFIG_FS_DAX
2146 		switch (token) {
2147 		case Opt_dax:
2148 		case Opt_dax_always:
2149 			if (is_remount &&
2150 			    (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2151 			     (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2152 			fail_dax_change_remount:
2153 				ext4_msg(sb, KERN_ERR, "can't change "
2154 					 "dax mount option while remounting");
2155 				return -1;
2156 			}
2157 			if (is_remount &&
2158 			    (test_opt(sb, DATA_FLAGS) ==
2159 			     EXT4_MOUNT_JOURNAL_DATA)) {
2160 				    ext4_msg(sb, KERN_ERR, "can't mount with "
2161 					     "both data=journal and dax");
2162 				    return -1;
2163 			}
2164 			ext4_msg(sb, KERN_WARNING,
2165 				"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2166 			sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2167 			sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2168 			break;
2169 		case Opt_dax_never:
2170 			if (is_remount &&
2171 			    (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2172 			     (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2173 				goto fail_dax_change_remount;
2174 			sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2175 			sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2176 			break;
2177 		case Opt_dax_inode:
2178 			if (is_remount &&
2179 			    ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2180 			     (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2181 			     !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2182 				goto fail_dax_change_remount;
2183 			sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2184 			sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2185 			/* Strictly for printing options */
2186 			sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2187 			break;
2188 		}
2189 #else
2190 		ext4_msg(sb, KERN_INFO, "dax option not supported");
2191 		sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2192 		sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2193 		return -1;
2194 #endif
2195 	} else if (token == Opt_data_err_abort) {
2196 		sbi->s_mount_opt |= m->mount_opt;
2197 	} else if (token == Opt_data_err_ignore) {
2198 		sbi->s_mount_opt &= ~m->mount_opt;
2199 	} else {
2200 		if (!args->from)
2201 			arg = 1;
2202 		if (m->flags & MOPT_CLEAR)
2203 			arg = !arg;
2204 		else if (unlikely(!(m->flags & MOPT_SET))) {
2205 			ext4_msg(sb, KERN_WARNING,
2206 				 "buggy handling of option %s", opt);
2207 			WARN_ON(1);
2208 			return -1;
2209 		}
2210 		if (arg != 0)
2211 			sbi->s_mount_opt |= m->mount_opt;
2212 		else
2213 			sbi->s_mount_opt &= ~m->mount_opt;
2214 	}
2215 	return 1;
2216 }
2217 
2218 static int parse_options(char *options, struct super_block *sb,
2219 			 unsigned long *journal_devnum,
2220 			 unsigned int *journal_ioprio,
2221 			 int is_remount)
2222 {
2223 	struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2224 	char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2225 	substring_t args[MAX_OPT_ARGS];
2226 	int token;
2227 
2228 	if (!options)
2229 		return 1;
2230 
2231 	while ((p = strsep(&options, ",")) != NULL) {
2232 		if (!*p)
2233 			continue;
2234 		/*
2235 		 * Initialize args struct so we know whether arg was
2236 		 * found; some options take optional arguments.
2237 		 */
2238 		args[0].to = args[0].from = NULL;
2239 		token = match_token(p, tokens, args);
2240 		if (handle_mount_opt(sb, p, token, args, journal_devnum,
2241 				     journal_ioprio, is_remount) < 0)
2242 			return 0;
2243 	}
2244 #ifdef CONFIG_QUOTA
2245 	/*
2246 	 * We do the test below only for project quotas. 'usrquota' and
2247 	 * 'grpquota' mount options are allowed even without quota feature
2248 	 * to support legacy quotas in quota files.
2249 	 */
2250 	if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2251 		ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2252 			 "Cannot enable project quota enforcement.");
2253 		return 0;
2254 	}
2255 	usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2256 	grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2257 	if (usr_qf_name || grp_qf_name) {
2258 		if (test_opt(sb, USRQUOTA) && usr_qf_name)
2259 			clear_opt(sb, USRQUOTA);
2260 
2261 		if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2262 			clear_opt(sb, GRPQUOTA);
2263 
2264 		if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2265 			ext4_msg(sb, KERN_ERR, "old and new quota "
2266 					"format mixing");
2267 			return 0;
2268 		}
2269 
2270 		if (!sbi->s_jquota_fmt) {
2271 			ext4_msg(sb, KERN_ERR, "journaled quota format "
2272 					"not specified");
2273 			return 0;
2274 		}
2275 	}
2276 #endif
2277 	if (test_opt(sb, DIOREAD_NOLOCK)) {
2278 		int blocksize =
2279 			BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2280 		if (blocksize < PAGE_SIZE)
2281 			ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2282 				 "experimental mount option 'dioread_nolock' "
2283 				 "for blocksize < PAGE_SIZE");
2284 	}
2285 	return 1;
2286 }
2287 
2288 static inline void ext4_show_quota_options(struct seq_file *seq,
2289 					   struct super_block *sb)
2290 {
2291 #if defined(CONFIG_QUOTA)
2292 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2293 	char *usr_qf_name, *grp_qf_name;
2294 
2295 	if (sbi->s_jquota_fmt) {
2296 		char *fmtname = "";
2297 
2298 		switch (sbi->s_jquota_fmt) {
2299 		case QFMT_VFS_OLD:
2300 			fmtname = "vfsold";
2301 			break;
2302 		case QFMT_VFS_V0:
2303 			fmtname = "vfsv0";
2304 			break;
2305 		case QFMT_VFS_V1:
2306 			fmtname = "vfsv1";
2307 			break;
2308 		}
2309 		seq_printf(seq, ",jqfmt=%s", fmtname);
2310 	}
2311 
2312 	rcu_read_lock();
2313 	usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2314 	grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2315 	if (usr_qf_name)
2316 		seq_show_option(seq, "usrjquota", usr_qf_name);
2317 	if (grp_qf_name)
2318 		seq_show_option(seq, "grpjquota", grp_qf_name);
2319 	rcu_read_unlock();
2320 #endif
2321 }
2322 
2323 static const char *token2str(int token)
2324 {
2325 	const struct match_token *t;
2326 
2327 	for (t = tokens; t->token != Opt_err; t++)
2328 		if (t->token == token && !strchr(t->pattern, '='))
2329 			break;
2330 	return t->pattern;
2331 }
2332 
2333 /*
2334  * Show an option if
2335  *  - it's set to a non-default value OR
2336  *  - if the per-sb default is different from the global default
2337  */
2338 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2339 			      int nodefs)
2340 {
2341 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2342 	struct ext4_super_block *es = sbi->s_es;
2343 	int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2344 	const struct mount_opts *m;
2345 	char sep = nodefs ? '\n' : ',';
2346 
2347 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2348 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2349 
2350 	if (sbi->s_sb_block != 1)
2351 		SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2352 
2353 	for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2354 		int want_set = m->flags & MOPT_SET;
2355 		if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2356 		    (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2357 			continue;
2358 		if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2359 			continue; /* skip if same as the default */
2360 		if ((want_set &&
2361 		     (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2362 		    (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2363 			continue; /* select Opt_noFoo vs Opt_Foo */
2364 		SEQ_OPTS_PRINT("%s", token2str(m->token));
2365 	}
2366 
2367 	if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2368 	    le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2369 		SEQ_OPTS_PRINT("resuid=%u",
2370 				from_kuid_munged(&init_user_ns, sbi->s_resuid));
2371 	if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2372 	    le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2373 		SEQ_OPTS_PRINT("resgid=%u",
2374 				from_kgid_munged(&init_user_ns, sbi->s_resgid));
2375 	def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2376 	if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2377 		SEQ_OPTS_PUTS("errors=remount-ro");
2378 	if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2379 		SEQ_OPTS_PUTS("errors=continue");
2380 	if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2381 		SEQ_OPTS_PUTS("errors=panic");
2382 	if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2383 		SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2384 	if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2385 		SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2386 	if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2387 		SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2388 	if (sb->s_flags & SB_I_VERSION)
2389 		SEQ_OPTS_PUTS("i_version");
2390 	if (nodefs || sbi->s_stripe)
2391 		SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2392 	if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2393 			(sbi->s_mount_opt ^ def_mount_opt)) {
2394 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2395 			SEQ_OPTS_PUTS("data=journal");
2396 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2397 			SEQ_OPTS_PUTS("data=ordered");
2398 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2399 			SEQ_OPTS_PUTS("data=writeback");
2400 	}
2401 	if (nodefs ||
2402 	    sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2403 		SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2404 			       sbi->s_inode_readahead_blks);
2405 
2406 	if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2407 		       (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2408 		SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2409 	if (nodefs || sbi->s_max_dir_size_kb)
2410 		SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2411 	if (test_opt(sb, DATA_ERR_ABORT))
2412 		SEQ_OPTS_PUTS("data_err=abort");
2413 
2414 	fscrypt_show_test_dummy_encryption(seq, sep, sb);
2415 
2416 	if (sb->s_flags & SB_INLINECRYPT)
2417 		SEQ_OPTS_PUTS("inlinecrypt");
2418 
2419 	if (test_opt(sb, DAX_ALWAYS)) {
2420 		if (IS_EXT2_SB(sb))
2421 			SEQ_OPTS_PUTS("dax");
2422 		else
2423 			SEQ_OPTS_PUTS("dax=always");
2424 	} else if (test_opt2(sb, DAX_NEVER)) {
2425 		SEQ_OPTS_PUTS("dax=never");
2426 	} else if (test_opt2(sb, DAX_INODE)) {
2427 		SEQ_OPTS_PUTS("dax=inode");
2428 	}
2429 
2430 	ext4_show_quota_options(seq, sb);
2431 	return 0;
2432 }
2433 
2434 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2435 {
2436 	return _ext4_show_options(seq, root->d_sb, 0);
2437 }
2438 
2439 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2440 {
2441 	struct super_block *sb = seq->private;
2442 	int rc;
2443 
2444 	seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2445 	rc = _ext4_show_options(seq, sb, 1);
2446 	seq_puts(seq, "\n");
2447 	return rc;
2448 }
2449 
2450 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2451 			    int read_only)
2452 {
2453 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2454 	int err = 0;
2455 
2456 	if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2457 		ext4_msg(sb, KERN_ERR, "revision level too high, "
2458 			 "forcing read-only mode");
2459 		err = -EROFS;
2460 		goto done;
2461 	}
2462 	if (read_only)
2463 		goto done;
2464 	if (!(sbi->s_mount_state & EXT4_VALID_FS))
2465 		ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2466 			 "running e2fsck is recommended");
2467 	else if (sbi->s_mount_state & EXT4_ERROR_FS)
2468 		ext4_msg(sb, KERN_WARNING,
2469 			 "warning: mounting fs with errors, "
2470 			 "running e2fsck is recommended");
2471 	else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2472 		 le16_to_cpu(es->s_mnt_count) >=
2473 		 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2474 		ext4_msg(sb, KERN_WARNING,
2475 			 "warning: maximal mount count reached, "
2476 			 "running e2fsck is recommended");
2477 	else if (le32_to_cpu(es->s_checkinterval) &&
2478 		 (ext4_get_tstamp(es, s_lastcheck) +
2479 		  le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2480 		ext4_msg(sb, KERN_WARNING,
2481 			 "warning: checktime reached, "
2482 			 "running e2fsck is recommended");
2483 	if (!sbi->s_journal)
2484 		es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2485 	if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2486 		es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2487 	le16_add_cpu(&es->s_mnt_count, 1);
2488 	ext4_update_tstamp(es, s_mtime);
2489 	if (sbi->s_journal)
2490 		ext4_set_feature_journal_needs_recovery(sb);
2491 
2492 	err = ext4_commit_super(sb, 1);
2493 done:
2494 	if (test_opt(sb, DEBUG))
2495 		printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2496 				"bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2497 			sb->s_blocksize,
2498 			sbi->s_groups_count,
2499 			EXT4_BLOCKS_PER_GROUP(sb),
2500 			EXT4_INODES_PER_GROUP(sb),
2501 			sbi->s_mount_opt, sbi->s_mount_opt2);
2502 
2503 	cleancache_init_fs(sb);
2504 	return err;
2505 }
2506 
2507 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2508 {
2509 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2510 	struct flex_groups **old_groups, **new_groups;
2511 	int size, i, j;
2512 
2513 	if (!sbi->s_log_groups_per_flex)
2514 		return 0;
2515 
2516 	size = ext4_flex_group(sbi, ngroup - 1) + 1;
2517 	if (size <= sbi->s_flex_groups_allocated)
2518 		return 0;
2519 
2520 	new_groups = kvzalloc(roundup_pow_of_two(size *
2521 			      sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2522 	if (!new_groups) {
2523 		ext4_msg(sb, KERN_ERR,
2524 			 "not enough memory for %d flex group pointers", size);
2525 		return -ENOMEM;
2526 	}
2527 	for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2528 		new_groups[i] = kvzalloc(roundup_pow_of_two(
2529 					 sizeof(struct flex_groups)),
2530 					 GFP_KERNEL);
2531 		if (!new_groups[i]) {
2532 			for (j = sbi->s_flex_groups_allocated; j < i; j++)
2533 				kvfree(new_groups[j]);
2534 			kvfree(new_groups);
2535 			ext4_msg(sb, KERN_ERR,
2536 				 "not enough memory for %d flex groups", size);
2537 			return -ENOMEM;
2538 		}
2539 	}
2540 	rcu_read_lock();
2541 	old_groups = rcu_dereference(sbi->s_flex_groups);
2542 	if (old_groups)
2543 		memcpy(new_groups, old_groups,
2544 		       (sbi->s_flex_groups_allocated *
2545 			sizeof(struct flex_groups *)));
2546 	rcu_read_unlock();
2547 	rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2548 	sbi->s_flex_groups_allocated = size;
2549 	if (old_groups)
2550 		ext4_kvfree_array_rcu(old_groups);
2551 	return 0;
2552 }
2553 
2554 static int ext4_fill_flex_info(struct super_block *sb)
2555 {
2556 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2557 	struct ext4_group_desc *gdp = NULL;
2558 	struct flex_groups *fg;
2559 	ext4_group_t flex_group;
2560 	int i, err;
2561 
2562 	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2563 	if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2564 		sbi->s_log_groups_per_flex = 0;
2565 		return 1;
2566 	}
2567 
2568 	err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2569 	if (err)
2570 		goto failed;
2571 
2572 	for (i = 0; i < sbi->s_groups_count; i++) {
2573 		gdp = ext4_get_group_desc(sb, i, NULL);
2574 
2575 		flex_group = ext4_flex_group(sbi, i);
2576 		fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2577 		atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2578 		atomic64_add(ext4_free_group_clusters(sb, gdp),
2579 			     &fg->free_clusters);
2580 		atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2581 	}
2582 
2583 	return 1;
2584 failed:
2585 	return 0;
2586 }
2587 
2588 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2589 				   struct ext4_group_desc *gdp)
2590 {
2591 	int offset = offsetof(struct ext4_group_desc, bg_checksum);
2592 	__u16 crc = 0;
2593 	__le32 le_group = cpu_to_le32(block_group);
2594 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2595 
2596 	if (ext4_has_metadata_csum(sbi->s_sb)) {
2597 		/* Use new metadata_csum algorithm */
2598 		__u32 csum32;
2599 		__u16 dummy_csum = 0;
2600 
2601 		csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2602 				     sizeof(le_group));
2603 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2604 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2605 				     sizeof(dummy_csum));
2606 		offset += sizeof(dummy_csum);
2607 		if (offset < sbi->s_desc_size)
2608 			csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2609 					     sbi->s_desc_size - offset);
2610 
2611 		crc = csum32 & 0xFFFF;
2612 		goto out;
2613 	}
2614 
2615 	/* old crc16 code */
2616 	if (!ext4_has_feature_gdt_csum(sb))
2617 		return 0;
2618 
2619 	crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2620 	crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2621 	crc = crc16(crc, (__u8 *)gdp, offset);
2622 	offset += sizeof(gdp->bg_checksum); /* skip checksum */
2623 	/* for checksum of struct ext4_group_desc do the rest...*/
2624 	if (ext4_has_feature_64bit(sb) &&
2625 	    offset < le16_to_cpu(sbi->s_es->s_desc_size))
2626 		crc = crc16(crc, (__u8 *)gdp + offset,
2627 			    le16_to_cpu(sbi->s_es->s_desc_size) -
2628 				offset);
2629 
2630 out:
2631 	return cpu_to_le16(crc);
2632 }
2633 
2634 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2635 				struct ext4_group_desc *gdp)
2636 {
2637 	if (ext4_has_group_desc_csum(sb) &&
2638 	    (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2639 		return 0;
2640 
2641 	return 1;
2642 }
2643 
2644 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2645 			      struct ext4_group_desc *gdp)
2646 {
2647 	if (!ext4_has_group_desc_csum(sb))
2648 		return;
2649 	gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2650 }
2651 
2652 /* Called at mount-time, super-block is locked */
2653 static int ext4_check_descriptors(struct super_block *sb,
2654 				  ext4_fsblk_t sb_block,
2655 				  ext4_group_t *first_not_zeroed)
2656 {
2657 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2658 	ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2659 	ext4_fsblk_t last_block;
2660 	ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2661 	ext4_fsblk_t block_bitmap;
2662 	ext4_fsblk_t inode_bitmap;
2663 	ext4_fsblk_t inode_table;
2664 	int flexbg_flag = 0;
2665 	ext4_group_t i, grp = sbi->s_groups_count;
2666 
2667 	if (ext4_has_feature_flex_bg(sb))
2668 		flexbg_flag = 1;
2669 
2670 	ext4_debug("Checking group descriptors");
2671 
2672 	for (i = 0; i < sbi->s_groups_count; i++) {
2673 		struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2674 
2675 		if (i == sbi->s_groups_count - 1 || flexbg_flag)
2676 			last_block = ext4_blocks_count(sbi->s_es) - 1;
2677 		else
2678 			last_block = first_block +
2679 				(EXT4_BLOCKS_PER_GROUP(sb) - 1);
2680 
2681 		if ((grp == sbi->s_groups_count) &&
2682 		   !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2683 			grp = i;
2684 
2685 		block_bitmap = ext4_block_bitmap(sb, gdp);
2686 		if (block_bitmap == sb_block) {
2687 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2688 				 "Block bitmap for group %u overlaps "
2689 				 "superblock", i);
2690 			if (!sb_rdonly(sb))
2691 				return 0;
2692 		}
2693 		if (block_bitmap >= sb_block + 1 &&
2694 		    block_bitmap <= last_bg_block) {
2695 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2696 				 "Block bitmap for group %u overlaps "
2697 				 "block group descriptors", i);
2698 			if (!sb_rdonly(sb))
2699 				return 0;
2700 		}
2701 		if (block_bitmap < first_block || block_bitmap > last_block) {
2702 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2703 			       "Block bitmap for group %u not in group "
2704 			       "(block %llu)!", i, block_bitmap);
2705 			return 0;
2706 		}
2707 		inode_bitmap = ext4_inode_bitmap(sb, gdp);
2708 		if (inode_bitmap == sb_block) {
2709 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2710 				 "Inode bitmap for group %u overlaps "
2711 				 "superblock", i);
2712 			if (!sb_rdonly(sb))
2713 				return 0;
2714 		}
2715 		if (inode_bitmap >= sb_block + 1 &&
2716 		    inode_bitmap <= last_bg_block) {
2717 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2718 				 "Inode bitmap for group %u overlaps "
2719 				 "block group descriptors", i);
2720 			if (!sb_rdonly(sb))
2721 				return 0;
2722 		}
2723 		if (inode_bitmap < first_block || inode_bitmap > last_block) {
2724 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2725 			       "Inode bitmap for group %u not in group "
2726 			       "(block %llu)!", i, inode_bitmap);
2727 			return 0;
2728 		}
2729 		inode_table = ext4_inode_table(sb, gdp);
2730 		if (inode_table == sb_block) {
2731 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2732 				 "Inode table for group %u overlaps "
2733 				 "superblock", i);
2734 			if (!sb_rdonly(sb))
2735 				return 0;
2736 		}
2737 		if (inode_table >= sb_block + 1 &&
2738 		    inode_table <= last_bg_block) {
2739 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2740 				 "Inode table for group %u overlaps "
2741 				 "block group descriptors", i);
2742 			if (!sb_rdonly(sb))
2743 				return 0;
2744 		}
2745 		if (inode_table < first_block ||
2746 		    inode_table + sbi->s_itb_per_group - 1 > last_block) {
2747 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2748 			       "Inode table for group %u not in group "
2749 			       "(block %llu)!", i, inode_table);
2750 			return 0;
2751 		}
2752 		ext4_lock_group(sb, i);
2753 		if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2754 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2755 				 "Checksum for group %u failed (%u!=%u)",
2756 				 i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2757 				     gdp)), le16_to_cpu(gdp->bg_checksum));
2758 			if (!sb_rdonly(sb)) {
2759 				ext4_unlock_group(sb, i);
2760 				return 0;
2761 			}
2762 		}
2763 		ext4_unlock_group(sb, i);
2764 		if (!flexbg_flag)
2765 			first_block += EXT4_BLOCKS_PER_GROUP(sb);
2766 	}
2767 	if (NULL != first_not_zeroed)
2768 		*first_not_zeroed = grp;
2769 	return 1;
2770 }
2771 
2772 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2773  * the superblock) which were deleted from all directories, but held open by
2774  * a process at the time of a crash.  We walk the list and try to delete these
2775  * inodes at recovery time (only with a read-write filesystem).
2776  *
2777  * In order to keep the orphan inode chain consistent during traversal (in
2778  * case of crash during recovery), we link each inode into the superblock
2779  * orphan list_head and handle it the same way as an inode deletion during
2780  * normal operation (which journals the operations for us).
2781  *
2782  * We only do an iget() and an iput() on each inode, which is very safe if we
2783  * accidentally point at an in-use or already deleted inode.  The worst that
2784  * can happen in this case is that we get a "bit already cleared" message from
2785  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2786  * e2fsck was run on this filesystem, and it must have already done the orphan
2787  * inode cleanup for us, so we can safely abort without any further action.
2788  */
2789 static void ext4_orphan_cleanup(struct super_block *sb,
2790 				struct ext4_super_block *es)
2791 {
2792 	unsigned int s_flags = sb->s_flags;
2793 	int ret, nr_orphans = 0, nr_truncates = 0;
2794 #ifdef CONFIG_QUOTA
2795 	int quota_update = 0;
2796 	int i;
2797 #endif
2798 	if (!es->s_last_orphan) {
2799 		jbd_debug(4, "no orphan inodes to clean up\n");
2800 		return;
2801 	}
2802 
2803 	if (bdev_read_only(sb->s_bdev)) {
2804 		ext4_msg(sb, KERN_ERR, "write access "
2805 			"unavailable, skipping orphan cleanup");
2806 		return;
2807 	}
2808 
2809 	/* Check if feature set would not allow a r/w mount */
2810 	if (!ext4_feature_set_ok(sb, 0)) {
2811 		ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2812 			 "unknown ROCOMPAT features");
2813 		return;
2814 	}
2815 
2816 	if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2817 		/* don't clear list on RO mount w/ errors */
2818 		if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2819 			ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2820 				  "clearing orphan list.\n");
2821 			es->s_last_orphan = 0;
2822 		}
2823 		jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2824 		return;
2825 	}
2826 
2827 	if (s_flags & SB_RDONLY) {
2828 		ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2829 		sb->s_flags &= ~SB_RDONLY;
2830 	}
2831 #ifdef CONFIG_QUOTA
2832 	/* Needed for iput() to work correctly and not trash data */
2833 	sb->s_flags |= SB_ACTIVE;
2834 
2835 	/*
2836 	 * Turn on quotas which were not enabled for read-only mounts if
2837 	 * filesystem has quota feature, so that they are updated correctly.
2838 	 */
2839 	if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2840 		int ret = ext4_enable_quotas(sb);
2841 
2842 		if (!ret)
2843 			quota_update = 1;
2844 		else
2845 			ext4_msg(sb, KERN_ERR,
2846 				"Cannot turn on quotas: error %d", ret);
2847 	}
2848 
2849 	/* Turn on journaled quotas used for old sytle */
2850 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2851 		if (EXT4_SB(sb)->s_qf_names[i]) {
2852 			int ret = ext4_quota_on_mount(sb, i);
2853 
2854 			if (!ret)
2855 				quota_update = 1;
2856 			else
2857 				ext4_msg(sb, KERN_ERR,
2858 					"Cannot turn on journaled "
2859 					"quota: type %d: error %d", i, ret);
2860 		}
2861 	}
2862 #endif
2863 
2864 	while (es->s_last_orphan) {
2865 		struct inode *inode;
2866 
2867 		/*
2868 		 * We may have encountered an error during cleanup; if
2869 		 * so, skip the rest.
2870 		 */
2871 		if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2872 			jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2873 			es->s_last_orphan = 0;
2874 			break;
2875 		}
2876 
2877 		inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2878 		if (IS_ERR(inode)) {
2879 			es->s_last_orphan = 0;
2880 			break;
2881 		}
2882 
2883 		list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2884 		dquot_initialize(inode);
2885 		if (inode->i_nlink) {
2886 			if (test_opt(sb, DEBUG))
2887 				ext4_msg(sb, KERN_DEBUG,
2888 					"%s: truncating inode %lu to %lld bytes",
2889 					__func__, inode->i_ino, inode->i_size);
2890 			jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2891 				  inode->i_ino, inode->i_size);
2892 			inode_lock(inode);
2893 			truncate_inode_pages(inode->i_mapping, inode->i_size);
2894 			ret = ext4_truncate(inode);
2895 			if (ret)
2896 				ext4_std_error(inode->i_sb, ret);
2897 			inode_unlock(inode);
2898 			nr_truncates++;
2899 		} else {
2900 			if (test_opt(sb, DEBUG))
2901 				ext4_msg(sb, KERN_DEBUG,
2902 					"%s: deleting unreferenced inode %lu",
2903 					__func__, inode->i_ino);
2904 			jbd_debug(2, "deleting unreferenced inode %lu\n",
2905 				  inode->i_ino);
2906 			nr_orphans++;
2907 		}
2908 		iput(inode);  /* The delete magic happens here! */
2909 	}
2910 
2911 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2912 
2913 	if (nr_orphans)
2914 		ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2915 		       PLURAL(nr_orphans));
2916 	if (nr_truncates)
2917 		ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2918 		       PLURAL(nr_truncates));
2919 #ifdef CONFIG_QUOTA
2920 	/* Turn off quotas if they were enabled for orphan cleanup */
2921 	if (quota_update) {
2922 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2923 			if (sb_dqopt(sb)->files[i])
2924 				dquot_quota_off(sb, i);
2925 		}
2926 	}
2927 #endif
2928 	sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2929 }
2930 
2931 /*
2932  * Maximal extent format file size.
2933  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2934  * extent format containers, within a sector_t, and within i_blocks
2935  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2936  * so that won't be a limiting factor.
2937  *
2938  * However there is other limiting factor. We do store extents in the form
2939  * of starting block and length, hence the resulting length of the extent
2940  * covering maximum file size must fit into on-disk format containers as
2941  * well. Given that length is always by 1 unit bigger than max unit (because
2942  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2943  *
2944  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2945  */
2946 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2947 {
2948 	loff_t res;
2949 	loff_t upper_limit = MAX_LFS_FILESIZE;
2950 
2951 	BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2952 
2953 	if (!has_huge_files) {
2954 		upper_limit = (1LL << 32) - 1;
2955 
2956 		/* total blocks in file system block size */
2957 		upper_limit >>= (blkbits - 9);
2958 		upper_limit <<= blkbits;
2959 	}
2960 
2961 	/*
2962 	 * 32-bit extent-start container, ee_block. We lower the maxbytes
2963 	 * by one fs block, so ee_len can cover the extent of maximum file
2964 	 * size
2965 	 */
2966 	res = (1LL << 32) - 1;
2967 	res <<= blkbits;
2968 
2969 	/* Sanity check against vm- & vfs- imposed limits */
2970 	if (res > upper_limit)
2971 		res = upper_limit;
2972 
2973 	return res;
2974 }
2975 
2976 /*
2977  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2978  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2979  * We need to be 1 filesystem block less than the 2^48 sector limit.
2980  */
2981 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2982 {
2983 	loff_t res = EXT4_NDIR_BLOCKS;
2984 	int meta_blocks;
2985 	loff_t upper_limit;
2986 	/* This is calculated to be the largest file size for a dense, block
2987 	 * mapped file such that the file's total number of 512-byte sectors,
2988 	 * including data and all indirect blocks, does not exceed (2^48 - 1).
2989 	 *
2990 	 * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2991 	 * number of 512-byte sectors of the file.
2992 	 */
2993 
2994 	if (!has_huge_files) {
2995 		/*
2996 		 * !has_huge_files or implies that the inode i_block field
2997 		 * represents total file blocks in 2^32 512-byte sectors ==
2998 		 * size of vfs inode i_blocks * 8
2999 		 */
3000 		upper_limit = (1LL << 32) - 1;
3001 
3002 		/* total blocks in file system block size */
3003 		upper_limit >>= (bits - 9);
3004 
3005 	} else {
3006 		/*
3007 		 * We use 48 bit ext4_inode i_blocks
3008 		 * With EXT4_HUGE_FILE_FL set the i_blocks
3009 		 * represent total number of blocks in
3010 		 * file system block size
3011 		 */
3012 		upper_limit = (1LL << 48) - 1;
3013 
3014 	}
3015 
3016 	/* indirect blocks */
3017 	meta_blocks = 1;
3018 	/* double indirect blocks */
3019 	meta_blocks += 1 + (1LL << (bits-2));
3020 	/* tripple indirect blocks */
3021 	meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3022 
3023 	upper_limit -= meta_blocks;
3024 	upper_limit <<= bits;
3025 
3026 	res += 1LL << (bits-2);
3027 	res += 1LL << (2*(bits-2));
3028 	res += 1LL << (3*(bits-2));
3029 	res <<= bits;
3030 	if (res > upper_limit)
3031 		res = upper_limit;
3032 
3033 	if (res > MAX_LFS_FILESIZE)
3034 		res = MAX_LFS_FILESIZE;
3035 
3036 	return res;
3037 }
3038 
3039 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3040 				   ext4_fsblk_t logical_sb_block, int nr)
3041 {
3042 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3043 	ext4_group_t bg, first_meta_bg;
3044 	int has_super = 0;
3045 
3046 	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3047 
3048 	if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3049 		return logical_sb_block + nr + 1;
3050 	bg = sbi->s_desc_per_block * nr;
3051 	if (ext4_bg_has_super(sb, bg))
3052 		has_super = 1;
3053 
3054 	/*
3055 	 * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3056 	 * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3057 	 * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3058 	 * compensate.
3059 	 */
3060 	if (sb->s_blocksize == 1024 && nr == 0 &&
3061 	    le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3062 		has_super++;
3063 
3064 	return (has_super + ext4_group_first_block_no(sb, bg));
3065 }
3066 
3067 /**
3068  * ext4_get_stripe_size: Get the stripe size.
3069  * @sbi: In memory super block info
3070  *
3071  * If we have specified it via mount option, then
3072  * use the mount option value. If the value specified at mount time is
3073  * greater than the blocks per group use the super block value.
3074  * If the super block value is greater than blocks per group return 0.
3075  * Allocator needs it be less than blocks per group.
3076  *
3077  */
3078 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3079 {
3080 	unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3081 	unsigned long stripe_width =
3082 			le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3083 	int ret;
3084 
3085 	if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3086 		ret = sbi->s_stripe;
3087 	else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3088 		ret = stripe_width;
3089 	else if (stride && stride <= sbi->s_blocks_per_group)
3090 		ret = stride;
3091 	else
3092 		ret = 0;
3093 
3094 	/*
3095 	 * If the stripe width is 1, this makes no sense and
3096 	 * we set it to 0 to turn off stripe handling code.
3097 	 */
3098 	if (ret <= 1)
3099 		ret = 0;
3100 
3101 	return ret;
3102 }
3103 
3104 /*
3105  * Check whether this filesystem can be mounted based on
3106  * the features present and the RDONLY/RDWR mount requested.
3107  * Returns 1 if this filesystem can be mounted as requested,
3108  * 0 if it cannot be.
3109  */
3110 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3111 {
3112 	if (ext4_has_unknown_ext4_incompat_features(sb)) {
3113 		ext4_msg(sb, KERN_ERR,
3114 			"Couldn't mount because of "
3115 			"unsupported optional features (%x)",
3116 			(le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3117 			~EXT4_FEATURE_INCOMPAT_SUPP));
3118 		return 0;
3119 	}
3120 
3121 #ifndef CONFIG_UNICODE
3122 	if (ext4_has_feature_casefold(sb)) {
3123 		ext4_msg(sb, KERN_ERR,
3124 			 "Filesystem with casefold feature cannot be "
3125 			 "mounted without CONFIG_UNICODE");
3126 		return 0;
3127 	}
3128 #endif
3129 
3130 	if (readonly)
3131 		return 1;
3132 
3133 	if (ext4_has_feature_readonly(sb)) {
3134 		ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3135 		sb->s_flags |= SB_RDONLY;
3136 		return 1;
3137 	}
3138 
3139 	/* Check that feature set is OK for a read-write mount */
3140 	if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3141 		ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3142 			 "unsupported optional features (%x)",
3143 			 (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3144 				~EXT4_FEATURE_RO_COMPAT_SUPP));
3145 		return 0;
3146 	}
3147 	if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3148 		ext4_msg(sb, KERN_ERR,
3149 			 "Can't support bigalloc feature without "
3150 			 "extents feature\n");
3151 		return 0;
3152 	}
3153 
3154 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3155 	if (!readonly && (ext4_has_feature_quota(sb) ||
3156 			  ext4_has_feature_project(sb))) {
3157 		ext4_msg(sb, KERN_ERR,
3158 			 "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3159 		return 0;
3160 	}
3161 #endif  /* CONFIG_QUOTA */
3162 	return 1;
3163 }
3164 
3165 /*
3166  * This function is called once a day if we have errors logged
3167  * on the file system
3168  */
3169 static void print_daily_error_info(struct timer_list *t)
3170 {
3171 	struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3172 	struct super_block *sb = sbi->s_sb;
3173 	struct ext4_super_block *es = sbi->s_es;
3174 
3175 	if (es->s_error_count)
3176 		/* fsck newer than v1.41.13 is needed to clean this condition. */
3177 		ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3178 			 le32_to_cpu(es->s_error_count));
3179 	if (es->s_first_error_time) {
3180 		printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3181 		       sb->s_id,
3182 		       ext4_get_tstamp(es, s_first_error_time),
3183 		       (int) sizeof(es->s_first_error_func),
3184 		       es->s_first_error_func,
3185 		       le32_to_cpu(es->s_first_error_line));
3186 		if (es->s_first_error_ino)
3187 			printk(KERN_CONT ": inode %u",
3188 			       le32_to_cpu(es->s_first_error_ino));
3189 		if (es->s_first_error_block)
3190 			printk(KERN_CONT ": block %llu", (unsigned long long)
3191 			       le64_to_cpu(es->s_first_error_block));
3192 		printk(KERN_CONT "\n");
3193 	}
3194 	if (es->s_last_error_time) {
3195 		printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3196 		       sb->s_id,
3197 		       ext4_get_tstamp(es, s_last_error_time),
3198 		       (int) sizeof(es->s_last_error_func),
3199 		       es->s_last_error_func,
3200 		       le32_to_cpu(es->s_last_error_line));
3201 		if (es->s_last_error_ino)
3202 			printk(KERN_CONT ": inode %u",
3203 			       le32_to_cpu(es->s_last_error_ino));
3204 		if (es->s_last_error_block)
3205 			printk(KERN_CONT ": block %llu", (unsigned long long)
3206 			       le64_to_cpu(es->s_last_error_block));
3207 		printk(KERN_CONT "\n");
3208 	}
3209 	mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3210 }
3211 
3212 /* Find next suitable group and run ext4_init_inode_table */
3213 static int ext4_run_li_request(struct ext4_li_request *elr)
3214 {
3215 	struct ext4_group_desc *gdp = NULL;
3216 	ext4_group_t group, ngroups;
3217 	struct super_block *sb;
3218 	unsigned long timeout = 0;
3219 	int ret = 0;
3220 
3221 	sb = elr->lr_super;
3222 	ngroups = EXT4_SB(sb)->s_groups_count;
3223 
3224 	for (group = elr->lr_next_group; group < ngroups; group++) {
3225 		gdp = ext4_get_group_desc(sb, group, NULL);
3226 		if (!gdp) {
3227 			ret = 1;
3228 			break;
3229 		}
3230 
3231 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3232 			break;
3233 	}
3234 
3235 	if (group >= ngroups)
3236 		ret = 1;
3237 
3238 	if (!ret) {
3239 		timeout = jiffies;
3240 		ret = ext4_init_inode_table(sb, group,
3241 					    elr->lr_timeout ? 0 : 1);
3242 		if (elr->lr_timeout == 0) {
3243 			timeout = (jiffies - timeout) *
3244 				  elr->lr_sbi->s_li_wait_mult;
3245 			elr->lr_timeout = timeout;
3246 		}
3247 		elr->lr_next_sched = jiffies + elr->lr_timeout;
3248 		elr->lr_next_group = group + 1;
3249 	}
3250 	return ret;
3251 }
3252 
3253 /*
3254  * Remove lr_request from the list_request and free the
3255  * request structure. Should be called with li_list_mtx held
3256  */
3257 static void ext4_remove_li_request(struct ext4_li_request *elr)
3258 {
3259 	struct ext4_sb_info *sbi;
3260 
3261 	if (!elr)
3262 		return;
3263 
3264 	sbi = elr->lr_sbi;
3265 
3266 	list_del(&elr->lr_request);
3267 	sbi->s_li_request = NULL;
3268 	kfree(elr);
3269 }
3270 
3271 static void ext4_unregister_li_request(struct super_block *sb)
3272 {
3273 	mutex_lock(&ext4_li_mtx);
3274 	if (!ext4_li_info) {
3275 		mutex_unlock(&ext4_li_mtx);
3276 		return;
3277 	}
3278 
3279 	mutex_lock(&ext4_li_info->li_list_mtx);
3280 	ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3281 	mutex_unlock(&ext4_li_info->li_list_mtx);
3282 	mutex_unlock(&ext4_li_mtx);
3283 }
3284 
3285 static struct task_struct *ext4_lazyinit_task;
3286 
3287 /*
3288  * This is the function where ext4lazyinit thread lives. It walks
3289  * through the request list searching for next scheduled filesystem.
3290  * When such a fs is found, run the lazy initialization request
3291  * (ext4_rn_li_request) and keep track of the time spend in this
3292  * function. Based on that time we compute next schedule time of
3293  * the request. When walking through the list is complete, compute
3294  * next waking time and put itself into sleep.
3295  */
3296 static int ext4_lazyinit_thread(void *arg)
3297 {
3298 	struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3299 	struct list_head *pos, *n;
3300 	struct ext4_li_request *elr;
3301 	unsigned long next_wakeup, cur;
3302 
3303 	BUG_ON(NULL == eli);
3304 
3305 cont_thread:
3306 	while (true) {
3307 		next_wakeup = MAX_JIFFY_OFFSET;
3308 
3309 		mutex_lock(&eli->li_list_mtx);
3310 		if (list_empty(&eli->li_request_list)) {
3311 			mutex_unlock(&eli->li_list_mtx);
3312 			goto exit_thread;
3313 		}
3314 		list_for_each_safe(pos, n, &eli->li_request_list) {
3315 			int err = 0;
3316 			int progress = 0;
3317 			elr = list_entry(pos, struct ext4_li_request,
3318 					 lr_request);
3319 
3320 			if (time_before(jiffies, elr->lr_next_sched)) {
3321 				if (time_before(elr->lr_next_sched, next_wakeup))
3322 					next_wakeup = elr->lr_next_sched;
3323 				continue;
3324 			}
3325 			if (down_read_trylock(&elr->lr_super->s_umount)) {
3326 				if (sb_start_write_trylock(elr->lr_super)) {
3327 					progress = 1;
3328 					/*
3329 					 * We hold sb->s_umount, sb can not
3330 					 * be removed from the list, it is
3331 					 * now safe to drop li_list_mtx
3332 					 */
3333 					mutex_unlock(&eli->li_list_mtx);
3334 					err = ext4_run_li_request(elr);
3335 					sb_end_write(elr->lr_super);
3336 					mutex_lock(&eli->li_list_mtx);
3337 					n = pos->next;
3338 				}
3339 				up_read((&elr->lr_super->s_umount));
3340 			}
3341 			/* error, remove the lazy_init job */
3342 			if (err) {
3343 				ext4_remove_li_request(elr);
3344 				continue;
3345 			}
3346 			if (!progress) {
3347 				elr->lr_next_sched = jiffies +
3348 					(prandom_u32()
3349 					 % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3350 			}
3351 			if (time_before(elr->lr_next_sched, next_wakeup))
3352 				next_wakeup = elr->lr_next_sched;
3353 		}
3354 		mutex_unlock(&eli->li_list_mtx);
3355 
3356 		try_to_freeze();
3357 
3358 		cur = jiffies;
3359 		if ((time_after_eq(cur, next_wakeup)) ||
3360 		    (MAX_JIFFY_OFFSET == next_wakeup)) {
3361 			cond_resched();
3362 			continue;
3363 		}
3364 
3365 		schedule_timeout_interruptible(next_wakeup - cur);
3366 
3367 		if (kthread_should_stop()) {
3368 			ext4_clear_request_list();
3369 			goto exit_thread;
3370 		}
3371 	}
3372 
3373 exit_thread:
3374 	/*
3375 	 * It looks like the request list is empty, but we need
3376 	 * to check it under the li_list_mtx lock, to prevent any
3377 	 * additions into it, and of course we should lock ext4_li_mtx
3378 	 * to atomically free the list and ext4_li_info, because at
3379 	 * this point another ext4 filesystem could be registering
3380 	 * new one.
3381 	 */
3382 	mutex_lock(&ext4_li_mtx);
3383 	mutex_lock(&eli->li_list_mtx);
3384 	if (!list_empty(&eli->li_request_list)) {
3385 		mutex_unlock(&eli->li_list_mtx);
3386 		mutex_unlock(&ext4_li_mtx);
3387 		goto cont_thread;
3388 	}
3389 	mutex_unlock(&eli->li_list_mtx);
3390 	kfree(ext4_li_info);
3391 	ext4_li_info = NULL;
3392 	mutex_unlock(&ext4_li_mtx);
3393 
3394 	return 0;
3395 }
3396 
3397 static void ext4_clear_request_list(void)
3398 {
3399 	struct list_head *pos, *n;
3400 	struct ext4_li_request *elr;
3401 
3402 	mutex_lock(&ext4_li_info->li_list_mtx);
3403 	list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3404 		elr = list_entry(pos, struct ext4_li_request,
3405 				 lr_request);
3406 		ext4_remove_li_request(elr);
3407 	}
3408 	mutex_unlock(&ext4_li_info->li_list_mtx);
3409 }
3410 
3411 static int ext4_run_lazyinit_thread(void)
3412 {
3413 	ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3414 					 ext4_li_info, "ext4lazyinit");
3415 	if (IS_ERR(ext4_lazyinit_task)) {
3416 		int err = PTR_ERR(ext4_lazyinit_task);
3417 		ext4_clear_request_list();
3418 		kfree(ext4_li_info);
3419 		ext4_li_info = NULL;
3420 		printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3421 				 "initialization thread\n",
3422 				 err);
3423 		return err;
3424 	}
3425 	ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3426 	return 0;
3427 }
3428 
3429 /*
3430  * Check whether it make sense to run itable init. thread or not.
3431  * If there is at least one uninitialized inode table, return
3432  * corresponding group number, else the loop goes through all
3433  * groups and return total number of groups.
3434  */
3435 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3436 {
3437 	ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3438 	struct ext4_group_desc *gdp = NULL;
3439 
3440 	if (!ext4_has_group_desc_csum(sb))
3441 		return ngroups;
3442 
3443 	for (group = 0; group < ngroups; group++) {
3444 		gdp = ext4_get_group_desc(sb, group, NULL);
3445 		if (!gdp)
3446 			continue;
3447 
3448 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3449 			break;
3450 	}
3451 
3452 	return group;
3453 }
3454 
3455 static int ext4_li_info_new(void)
3456 {
3457 	struct ext4_lazy_init *eli = NULL;
3458 
3459 	eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3460 	if (!eli)
3461 		return -ENOMEM;
3462 
3463 	INIT_LIST_HEAD(&eli->li_request_list);
3464 	mutex_init(&eli->li_list_mtx);
3465 
3466 	eli->li_state |= EXT4_LAZYINIT_QUIT;
3467 
3468 	ext4_li_info = eli;
3469 
3470 	return 0;
3471 }
3472 
3473 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3474 					    ext4_group_t start)
3475 {
3476 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3477 	struct ext4_li_request *elr;
3478 
3479 	elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3480 	if (!elr)
3481 		return NULL;
3482 
3483 	elr->lr_super = sb;
3484 	elr->lr_sbi = sbi;
3485 	elr->lr_next_group = start;
3486 
3487 	/*
3488 	 * Randomize first schedule time of the request to
3489 	 * spread the inode table initialization requests
3490 	 * better.
3491 	 */
3492 	elr->lr_next_sched = jiffies + (prandom_u32() %
3493 				(EXT4_DEF_LI_MAX_START_DELAY * HZ));
3494 	return elr;
3495 }
3496 
3497 int ext4_register_li_request(struct super_block *sb,
3498 			     ext4_group_t first_not_zeroed)
3499 {
3500 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3501 	struct ext4_li_request *elr = NULL;
3502 	ext4_group_t ngroups = sbi->s_groups_count;
3503 	int ret = 0;
3504 
3505 	mutex_lock(&ext4_li_mtx);
3506 	if (sbi->s_li_request != NULL) {
3507 		/*
3508 		 * Reset timeout so it can be computed again, because
3509 		 * s_li_wait_mult might have changed.
3510 		 */
3511 		sbi->s_li_request->lr_timeout = 0;
3512 		goto out;
3513 	}
3514 
3515 	if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3516 	    !test_opt(sb, INIT_INODE_TABLE))
3517 		goto out;
3518 
3519 	elr = ext4_li_request_new(sb, first_not_zeroed);
3520 	if (!elr) {
3521 		ret = -ENOMEM;
3522 		goto out;
3523 	}
3524 
3525 	if (NULL == ext4_li_info) {
3526 		ret = ext4_li_info_new();
3527 		if (ret)
3528 			goto out;
3529 	}
3530 
3531 	mutex_lock(&ext4_li_info->li_list_mtx);
3532 	list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3533 	mutex_unlock(&ext4_li_info->li_list_mtx);
3534 
3535 	sbi->s_li_request = elr;
3536 	/*
3537 	 * set elr to NULL here since it has been inserted to
3538 	 * the request_list and the removal and free of it is
3539 	 * handled by ext4_clear_request_list from now on.
3540 	 */
3541 	elr = NULL;
3542 
3543 	if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3544 		ret = ext4_run_lazyinit_thread();
3545 		if (ret)
3546 			goto out;
3547 	}
3548 out:
3549 	mutex_unlock(&ext4_li_mtx);
3550 	if (ret)
3551 		kfree(elr);
3552 	return ret;
3553 }
3554 
3555 /*
3556  * We do not need to lock anything since this is called on
3557  * module unload.
3558  */
3559 static void ext4_destroy_lazyinit_thread(void)
3560 {
3561 	/*
3562 	 * If thread exited earlier
3563 	 * there's nothing to be done.
3564 	 */
3565 	if (!ext4_li_info || !ext4_lazyinit_task)
3566 		return;
3567 
3568 	kthread_stop(ext4_lazyinit_task);
3569 }
3570 
3571 static int set_journal_csum_feature_set(struct super_block *sb)
3572 {
3573 	int ret = 1;
3574 	int compat, incompat;
3575 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3576 
3577 	if (ext4_has_metadata_csum(sb)) {
3578 		/* journal checksum v3 */
3579 		compat = 0;
3580 		incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3581 	} else {
3582 		/* journal checksum v1 */
3583 		compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3584 		incompat = 0;
3585 	}
3586 
3587 	jbd2_journal_clear_features(sbi->s_journal,
3588 			JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3589 			JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3590 			JBD2_FEATURE_INCOMPAT_CSUM_V2);
3591 	if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3592 		ret = jbd2_journal_set_features(sbi->s_journal,
3593 				compat, 0,
3594 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3595 				incompat);
3596 	} else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3597 		ret = jbd2_journal_set_features(sbi->s_journal,
3598 				compat, 0,
3599 				incompat);
3600 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3601 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3602 	} else {
3603 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3604 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3605 	}
3606 
3607 	return ret;
3608 }
3609 
3610 /*
3611  * Note: calculating the overhead so we can be compatible with
3612  * historical BSD practice is quite difficult in the face of
3613  * clusters/bigalloc.  This is because multiple metadata blocks from
3614  * different block group can end up in the same allocation cluster.
3615  * Calculating the exact overhead in the face of clustered allocation
3616  * requires either O(all block bitmaps) in memory or O(number of block
3617  * groups**2) in time.  We will still calculate the superblock for
3618  * older file systems --- and if we come across with a bigalloc file
3619  * system with zero in s_overhead_clusters the estimate will be close to
3620  * correct especially for very large cluster sizes --- but for newer
3621  * file systems, it's better to calculate this figure once at mkfs
3622  * time, and store it in the superblock.  If the superblock value is
3623  * present (even for non-bigalloc file systems), we will use it.
3624  */
3625 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3626 			  char *buf)
3627 {
3628 	struct ext4_sb_info	*sbi = EXT4_SB(sb);
3629 	struct ext4_group_desc	*gdp;
3630 	ext4_fsblk_t		first_block, last_block, b;
3631 	ext4_group_t		i, ngroups = ext4_get_groups_count(sb);
3632 	int			s, j, count = 0;
3633 
3634 	if (!ext4_has_feature_bigalloc(sb))
3635 		return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3636 			sbi->s_itb_per_group + 2);
3637 
3638 	first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3639 		(grp * EXT4_BLOCKS_PER_GROUP(sb));
3640 	last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3641 	for (i = 0; i < ngroups; i++) {
3642 		gdp = ext4_get_group_desc(sb, i, NULL);
3643 		b = ext4_block_bitmap(sb, gdp);
3644 		if (b >= first_block && b <= last_block) {
3645 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3646 			count++;
3647 		}
3648 		b = ext4_inode_bitmap(sb, gdp);
3649 		if (b >= first_block && b <= last_block) {
3650 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3651 			count++;
3652 		}
3653 		b = ext4_inode_table(sb, gdp);
3654 		if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3655 			for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3656 				int c = EXT4_B2C(sbi, b - first_block);
3657 				ext4_set_bit(c, buf);
3658 				count++;
3659 			}
3660 		if (i != grp)
3661 			continue;
3662 		s = 0;
3663 		if (ext4_bg_has_super(sb, grp)) {
3664 			ext4_set_bit(s++, buf);
3665 			count++;
3666 		}
3667 		j = ext4_bg_num_gdb(sb, grp);
3668 		if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3669 			ext4_error(sb, "Invalid number of block group "
3670 				   "descriptor blocks: %d", j);
3671 			j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3672 		}
3673 		count += j;
3674 		for (; j > 0; j--)
3675 			ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3676 	}
3677 	if (!count)
3678 		return 0;
3679 	return EXT4_CLUSTERS_PER_GROUP(sb) -
3680 		ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3681 }
3682 
3683 /*
3684  * Compute the overhead and stash it in sbi->s_overhead
3685  */
3686 int ext4_calculate_overhead(struct super_block *sb)
3687 {
3688 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3689 	struct ext4_super_block *es = sbi->s_es;
3690 	struct inode *j_inode;
3691 	unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3692 	ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3693 	ext4_fsblk_t overhead = 0;
3694 	char *buf = (char *) get_zeroed_page(GFP_NOFS);
3695 
3696 	if (!buf)
3697 		return -ENOMEM;
3698 
3699 	/*
3700 	 * Compute the overhead (FS structures).  This is constant
3701 	 * for a given filesystem unless the number of block groups
3702 	 * changes so we cache the previous value until it does.
3703 	 */
3704 
3705 	/*
3706 	 * All of the blocks before first_data_block are overhead
3707 	 */
3708 	overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3709 
3710 	/*
3711 	 * Add the overhead found in each block group
3712 	 */
3713 	for (i = 0; i < ngroups; i++) {
3714 		int blks;
3715 
3716 		blks = count_overhead(sb, i, buf);
3717 		overhead += blks;
3718 		if (blks)
3719 			memset(buf, 0, PAGE_SIZE);
3720 		cond_resched();
3721 	}
3722 
3723 	/*
3724 	 * Add the internal journal blocks whether the journal has been
3725 	 * loaded or not
3726 	 */
3727 	if (sbi->s_journal && !sbi->journal_bdev)
3728 		overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3729 	else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3730 		/* j_inum for internal journal is non-zero */
3731 		j_inode = ext4_get_journal_inode(sb, j_inum);
3732 		if (j_inode) {
3733 			j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3734 			overhead += EXT4_NUM_B2C(sbi, j_blocks);
3735 			iput(j_inode);
3736 		} else {
3737 			ext4_msg(sb, KERN_ERR, "can't get journal size");
3738 		}
3739 	}
3740 	sbi->s_overhead = overhead;
3741 	smp_wmb();
3742 	free_page((unsigned long) buf);
3743 	return 0;
3744 }
3745 
3746 static void ext4_set_resv_clusters(struct super_block *sb)
3747 {
3748 	ext4_fsblk_t resv_clusters;
3749 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3750 
3751 	/*
3752 	 * There's no need to reserve anything when we aren't using extents.
3753 	 * The space estimates are exact, there are no unwritten extents,
3754 	 * hole punching doesn't need new metadata... This is needed especially
3755 	 * to keep ext2/3 backward compatibility.
3756 	 */
3757 	if (!ext4_has_feature_extents(sb))
3758 		return;
3759 	/*
3760 	 * By default we reserve 2% or 4096 clusters, whichever is smaller.
3761 	 * This should cover the situations where we can not afford to run
3762 	 * out of space like for example punch hole, or converting
3763 	 * unwritten extents in delalloc path. In most cases such
3764 	 * allocation would require 1, or 2 blocks, higher numbers are
3765 	 * very rare.
3766 	 */
3767 	resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3768 			 sbi->s_cluster_bits);
3769 
3770 	do_div(resv_clusters, 50);
3771 	resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3772 
3773 	atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3774 }
3775 
3776 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3777 {
3778 	struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3779 	char *orig_data = kstrdup(data, GFP_KERNEL);
3780 	struct buffer_head *bh, **group_desc;
3781 	struct ext4_super_block *es = NULL;
3782 	struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3783 	struct flex_groups **flex_groups;
3784 	ext4_fsblk_t block;
3785 	ext4_fsblk_t sb_block = get_sb_block(&data);
3786 	ext4_fsblk_t logical_sb_block;
3787 	unsigned long offset = 0;
3788 	unsigned long journal_devnum = 0;
3789 	unsigned long def_mount_opts;
3790 	struct inode *root;
3791 	const char *descr;
3792 	int ret = -ENOMEM;
3793 	int blocksize, clustersize;
3794 	unsigned int db_count;
3795 	unsigned int i;
3796 	int needs_recovery, has_huge_files;
3797 	__u64 blocks_count;
3798 	int err = 0;
3799 	unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3800 	ext4_group_t first_not_zeroed;
3801 
3802 	if ((data && !orig_data) || !sbi)
3803 		goto out_free_base;
3804 
3805 	sbi->s_daxdev = dax_dev;
3806 	sbi->s_blockgroup_lock =
3807 		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3808 	if (!sbi->s_blockgroup_lock)
3809 		goto out_free_base;
3810 
3811 	sb->s_fs_info = sbi;
3812 	sbi->s_sb = sb;
3813 	sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3814 	sbi->s_sb_block = sb_block;
3815 	if (sb->s_bdev->bd_part)
3816 		sbi->s_sectors_written_start =
3817 			part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3818 
3819 	/* Cleanup superblock name */
3820 	strreplace(sb->s_id, '/', '!');
3821 
3822 	/* -EINVAL is default */
3823 	ret = -EINVAL;
3824 	blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3825 	if (!blocksize) {
3826 		ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3827 		goto out_fail;
3828 	}
3829 
3830 	/*
3831 	 * The ext4 superblock will not be buffer aligned for other than 1kB
3832 	 * block sizes.  We need to calculate the offset from buffer start.
3833 	 */
3834 	if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3835 		logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3836 		offset = do_div(logical_sb_block, blocksize);
3837 	} else {
3838 		logical_sb_block = sb_block;
3839 	}
3840 
3841 	if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3842 		ext4_msg(sb, KERN_ERR, "unable to read superblock");
3843 		goto out_fail;
3844 	}
3845 	/*
3846 	 * Note: s_es must be initialized as soon as possible because
3847 	 *       some ext4 macro-instructions depend on its value
3848 	 */
3849 	es = (struct ext4_super_block *) (bh->b_data + offset);
3850 	sbi->s_es = es;
3851 	sb->s_magic = le16_to_cpu(es->s_magic);
3852 	if (sb->s_magic != EXT4_SUPER_MAGIC)
3853 		goto cantfind_ext4;
3854 	sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3855 
3856 	/* Warn if metadata_csum and gdt_csum are both set. */
3857 	if (ext4_has_feature_metadata_csum(sb) &&
3858 	    ext4_has_feature_gdt_csum(sb))
3859 		ext4_warning(sb, "metadata_csum and uninit_bg are "
3860 			     "redundant flags; please run fsck.");
3861 
3862 	/* Check for a known checksum algorithm */
3863 	if (!ext4_verify_csum_type(sb, es)) {
3864 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3865 			 "unknown checksum algorithm.");
3866 		silent = 1;
3867 		goto cantfind_ext4;
3868 	}
3869 
3870 	/* Load the checksum driver */
3871 	sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3872 	if (IS_ERR(sbi->s_chksum_driver)) {
3873 		ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3874 		ret = PTR_ERR(sbi->s_chksum_driver);
3875 		sbi->s_chksum_driver = NULL;
3876 		goto failed_mount;
3877 	}
3878 
3879 	/* Check superblock checksum */
3880 	if (!ext4_superblock_csum_verify(sb, es)) {
3881 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3882 			 "invalid superblock checksum.  Run e2fsck?");
3883 		silent = 1;
3884 		ret = -EFSBADCRC;
3885 		goto cantfind_ext4;
3886 	}
3887 
3888 	/* Precompute checksum seed for all metadata */
3889 	if (ext4_has_feature_csum_seed(sb))
3890 		sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3891 	else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3892 		sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3893 					       sizeof(es->s_uuid));
3894 
3895 	/* Set defaults before we parse the mount options */
3896 	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3897 	set_opt(sb, INIT_INODE_TABLE);
3898 	if (def_mount_opts & EXT4_DEFM_DEBUG)
3899 		set_opt(sb, DEBUG);
3900 	if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3901 		set_opt(sb, GRPID);
3902 	if (def_mount_opts & EXT4_DEFM_UID16)
3903 		set_opt(sb, NO_UID32);
3904 	/* xattr user namespace & acls are now defaulted on */
3905 	set_opt(sb, XATTR_USER);
3906 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3907 	set_opt(sb, POSIX_ACL);
3908 #endif
3909 	/* don't forget to enable journal_csum when metadata_csum is enabled. */
3910 	if (ext4_has_metadata_csum(sb))
3911 		set_opt(sb, JOURNAL_CHECKSUM);
3912 
3913 	if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3914 		set_opt(sb, JOURNAL_DATA);
3915 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3916 		set_opt(sb, ORDERED_DATA);
3917 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3918 		set_opt(sb, WRITEBACK_DATA);
3919 
3920 	if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3921 		set_opt(sb, ERRORS_PANIC);
3922 	else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3923 		set_opt(sb, ERRORS_CONT);
3924 	else
3925 		set_opt(sb, ERRORS_RO);
3926 	/* block_validity enabled by default; disable with noblock_validity */
3927 	set_opt(sb, BLOCK_VALIDITY);
3928 	if (def_mount_opts & EXT4_DEFM_DISCARD)
3929 		set_opt(sb, DISCARD);
3930 
3931 	sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3932 	sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3933 	sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3934 	sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3935 	sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3936 
3937 	if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3938 		set_opt(sb, BARRIER);
3939 
3940 	/*
3941 	 * enable delayed allocation by default
3942 	 * Use -o nodelalloc to turn it off
3943 	 */
3944 	if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3945 	    ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3946 		set_opt(sb, DELALLOC);
3947 
3948 	/*
3949 	 * set default s_li_wait_mult for lazyinit, for the case there is
3950 	 * no mount option specified.
3951 	 */
3952 	sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3953 
3954 	blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3955 
3956 	if (blocksize == PAGE_SIZE)
3957 		set_opt(sb, DIOREAD_NOLOCK);
3958 
3959 	if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3960 	    blocksize > EXT4_MAX_BLOCK_SIZE) {
3961 		ext4_msg(sb, KERN_ERR,
3962 		       "Unsupported filesystem blocksize %d (%d log_block_size)",
3963 			 blocksize, le32_to_cpu(es->s_log_block_size));
3964 		goto failed_mount;
3965 	}
3966 
3967 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3968 		sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3969 		sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3970 	} else {
3971 		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3972 		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3973 		if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3974 			ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3975 				 sbi->s_first_ino);
3976 			goto failed_mount;
3977 		}
3978 		if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3979 		    (!is_power_of_2(sbi->s_inode_size)) ||
3980 		    (sbi->s_inode_size > blocksize)) {
3981 			ext4_msg(sb, KERN_ERR,
3982 			       "unsupported inode size: %d",
3983 			       sbi->s_inode_size);
3984 			ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
3985 			goto failed_mount;
3986 		}
3987 		/*
3988 		 * i_atime_extra is the last extra field available for
3989 		 * [acm]times in struct ext4_inode. Checking for that
3990 		 * field should suffice to ensure we have extra space
3991 		 * for all three.
3992 		 */
3993 		if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
3994 			sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
3995 			sb->s_time_gran = 1;
3996 			sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
3997 		} else {
3998 			sb->s_time_gran = NSEC_PER_SEC;
3999 			sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4000 		}
4001 		sb->s_time_min = EXT4_TIMESTAMP_MIN;
4002 	}
4003 	if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4004 		sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4005 			EXT4_GOOD_OLD_INODE_SIZE;
4006 		if (ext4_has_feature_extra_isize(sb)) {
4007 			unsigned v, max = (sbi->s_inode_size -
4008 					   EXT4_GOOD_OLD_INODE_SIZE);
4009 
4010 			v = le16_to_cpu(es->s_want_extra_isize);
4011 			if (v > max) {
4012 				ext4_msg(sb, KERN_ERR,
4013 					 "bad s_want_extra_isize: %d", v);
4014 				goto failed_mount;
4015 			}
4016 			if (sbi->s_want_extra_isize < v)
4017 				sbi->s_want_extra_isize = v;
4018 
4019 			v = le16_to_cpu(es->s_min_extra_isize);
4020 			if (v > max) {
4021 				ext4_msg(sb, KERN_ERR,
4022 					 "bad s_min_extra_isize: %d", v);
4023 				goto failed_mount;
4024 			}
4025 			if (sbi->s_want_extra_isize < v)
4026 				sbi->s_want_extra_isize = v;
4027 		}
4028 	}
4029 
4030 	if (sbi->s_es->s_mount_opts[0]) {
4031 		char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4032 					      sizeof(sbi->s_es->s_mount_opts),
4033 					      GFP_KERNEL);
4034 		if (!s_mount_opts)
4035 			goto failed_mount;
4036 		if (!parse_options(s_mount_opts, sb, &journal_devnum,
4037 				   &journal_ioprio, 0)) {
4038 			ext4_msg(sb, KERN_WARNING,
4039 				 "failed to parse options in superblock: %s",
4040 				 s_mount_opts);
4041 		}
4042 		kfree(s_mount_opts);
4043 	}
4044 	sbi->s_def_mount_opt = sbi->s_mount_opt;
4045 	if (!parse_options((char *) data, sb, &journal_devnum,
4046 			   &journal_ioprio, 0))
4047 		goto failed_mount;
4048 
4049 #ifdef CONFIG_UNICODE
4050 	if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
4051 		const struct ext4_sb_encodings *encoding_info;
4052 		struct unicode_map *encoding;
4053 		__u16 encoding_flags;
4054 
4055 		if (ext4_has_feature_encrypt(sb)) {
4056 			ext4_msg(sb, KERN_ERR,
4057 				 "Can't mount with encoding and encryption");
4058 			goto failed_mount;
4059 		}
4060 
4061 		if (ext4_sb_read_encoding(es, &encoding_info,
4062 					  &encoding_flags)) {
4063 			ext4_msg(sb, KERN_ERR,
4064 				 "Encoding requested by superblock is unknown");
4065 			goto failed_mount;
4066 		}
4067 
4068 		encoding = utf8_load(encoding_info->version);
4069 		if (IS_ERR(encoding)) {
4070 			ext4_msg(sb, KERN_ERR,
4071 				 "can't mount with superblock charset: %s-%s "
4072 				 "not supported by the kernel. flags: 0x%x.",
4073 				 encoding_info->name, encoding_info->version,
4074 				 encoding_flags);
4075 			goto failed_mount;
4076 		}
4077 		ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4078 			 "%s-%s with flags 0x%hx", encoding_info->name,
4079 			 encoding_info->version?:"\b", encoding_flags);
4080 
4081 		sbi->s_encoding = encoding;
4082 		sbi->s_encoding_flags = encoding_flags;
4083 	}
4084 #endif
4085 
4086 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4087 		printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!\n");
4088 		/* can't mount with both data=journal and dioread_nolock. */
4089 		clear_opt(sb, DIOREAD_NOLOCK);
4090 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4091 			ext4_msg(sb, KERN_ERR, "can't mount with "
4092 				 "both data=journal and delalloc");
4093 			goto failed_mount;
4094 		}
4095 		if (test_opt(sb, DAX_ALWAYS)) {
4096 			ext4_msg(sb, KERN_ERR, "can't mount with "
4097 				 "both data=journal and dax");
4098 			goto failed_mount;
4099 		}
4100 		if (ext4_has_feature_encrypt(sb)) {
4101 			ext4_msg(sb, KERN_WARNING,
4102 				 "encrypted files will use data=ordered "
4103 				 "instead of data journaling mode");
4104 		}
4105 		if (test_opt(sb, DELALLOC))
4106 			clear_opt(sb, DELALLOC);
4107 	} else {
4108 		sb->s_iflags |= SB_I_CGROUPWB;
4109 	}
4110 
4111 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4112 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4113 
4114 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4115 	    (ext4_has_compat_features(sb) ||
4116 	     ext4_has_ro_compat_features(sb) ||
4117 	     ext4_has_incompat_features(sb)))
4118 		ext4_msg(sb, KERN_WARNING,
4119 		       "feature flags set on rev 0 fs, "
4120 		       "running e2fsck is recommended");
4121 
4122 	if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4123 		set_opt2(sb, HURD_COMPAT);
4124 		if (ext4_has_feature_64bit(sb)) {
4125 			ext4_msg(sb, KERN_ERR,
4126 				 "The Hurd can't support 64-bit file systems");
4127 			goto failed_mount;
4128 		}
4129 
4130 		/*
4131 		 * ea_inode feature uses l_i_version field which is not
4132 		 * available in HURD_COMPAT mode.
4133 		 */
4134 		if (ext4_has_feature_ea_inode(sb)) {
4135 			ext4_msg(sb, KERN_ERR,
4136 				 "ea_inode feature is not supported for Hurd");
4137 			goto failed_mount;
4138 		}
4139 	}
4140 
4141 	if (IS_EXT2_SB(sb)) {
4142 		if (ext2_feature_set_ok(sb))
4143 			ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4144 				 "using the ext4 subsystem");
4145 		else {
4146 			/*
4147 			 * If we're probing be silent, if this looks like
4148 			 * it's actually an ext[34] filesystem.
4149 			 */
4150 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4151 				goto failed_mount;
4152 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4153 				 "to feature incompatibilities");
4154 			goto failed_mount;
4155 		}
4156 	}
4157 
4158 	if (IS_EXT3_SB(sb)) {
4159 		if (ext3_feature_set_ok(sb))
4160 			ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4161 				 "using the ext4 subsystem");
4162 		else {
4163 			/*
4164 			 * If we're probing be silent, if this looks like
4165 			 * it's actually an ext4 filesystem.
4166 			 */
4167 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4168 				goto failed_mount;
4169 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4170 				 "to feature incompatibilities");
4171 			goto failed_mount;
4172 		}
4173 	}
4174 
4175 	/*
4176 	 * Check feature flags regardless of the revision level, since we
4177 	 * previously didn't change the revision level when setting the flags,
4178 	 * so there is a chance incompat flags are set on a rev 0 filesystem.
4179 	 */
4180 	if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4181 		goto failed_mount;
4182 
4183 	if (le32_to_cpu(es->s_log_block_size) >
4184 	    (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4185 		ext4_msg(sb, KERN_ERR,
4186 			 "Invalid log block size: %u",
4187 			 le32_to_cpu(es->s_log_block_size));
4188 		goto failed_mount;
4189 	}
4190 	if (le32_to_cpu(es->s_log_cluster_size) >
4191 	    (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4192 		ext4_msg(sb, KERN_ERR,
4193 			 "Invalid log cluster size: %u",
4194 			 le32_to_cpu(es->s_log_cluster_size));
4195 		goto failed_mount;
4196 	}
4197 
4198 	if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4199 		ext4_msg(sb, KERN_ERR,
4200 			 "Number of reserved GDT blocks insanely large: %d",
4201 			 le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4202 		goto failed_mount;
4203 	}
4204 
4205 	if (bdev_dax_supported(sb->s_bdev, blocksize))
4206 		set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4207 
4208 	if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4209 		if (ext4_has_feature_inline_data(sb)) {
4210 			ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4211 					" that may contain inline data");
4212 			goto failed_mount;
4213 		}
4214 		if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4215 			ext4_msg(sb, KERN_ERR,
4216 				"DAX unsupported by block device.");
4217 			goto failed_mount;
4218 		}
4219 	}
4220 
4221 	if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4222 		ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4223 			 es->s_encryption_level);
4224 		goto failed_mount;
4225 	}
4226 
4227 	if (sb->s_blocksize != blocksize) {
4228 		/* Validate the filesystem blocksize */
4229 		if (!sb_set_blocksize(sb, blocksize)) {
4230 			ext4_msg(sb, KERN_ERR, "bad block size %d",
4231 					blocksize);
4232 			goto failed_mount;
4233 		}
4234 
4235 		brelse(bh);
4236 		logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4237 		offset = do_div(logical_sb_block, blocksize);
4238 		bh = sb_bread_unmovable(sb, logical_sb_block);
4239 		if (!bh) {
4240 			ext4_msg(sb, KERN_ERR,
4241 			       "Can't read superblock on 2nd try");
4242 			goto failed_mount;
4243 		}
4244 		es = (struct ext4_super_block *)(bh->b_data + offset);
4245 		sbi->s_es = es;
4246 		if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4247 			ext4_msg(sb, KERN_ERR,
4248 			       "Magic mismatch, very weird!");
4249 			goto failed_mount;
4250 		}
4251 	}
4252 
4253 	has_huge_files = ext4_has_feature_huge_file(sb);
4254 	sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4255 						      has_huge_files);
4256 	sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4257 
4258 	sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4259 	if (ext4_has_feature_64bit(sb)) {
4260 		if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4261 		    sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4262 		    !is_power_of_2(sbi->s_desc_size)) {
4263 			ext4_msg(sb, KERN_ERR,
4264 			       "unsupported descriptor size %lu",
4265 			       sbi->s_desc_size);
4266 			goto failed_mount;
4267 		}
4268 	} else
4269 		sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4270 
4271 	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4272 	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4273 
4274 	sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4275 	if (sbi->s_inodes_per_block == 0)
4276 		goto cantfind_ext4;
4277 	if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4278 	    sbi->s_inodes_per_group > blocksize * 8) {
4279 		ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4280 			 sbi->s_inodes_per_group);
4281 		goto failed_mount;
4282 	}
4283 	sbi->s_itb_per_group = sbi->s_inodes_per_group /
4284 					sbi->s_inodes_per_block;
4285 	sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4286 	sbi->s_sbh = bh;
4287 	sbi->s_mount_state = le16_to_cpu(es->s_state);
4288 	sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4289 	sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4290 
4291 	for (i = 0; i < 4; i++)
4292 		sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4293 	sbi->s_def_hash_version = es->s_def_hash_version;
4294 	if (ext4_has_feature_dir_index(sb)) {
4295 		i = le32_to_cpu(es->s_flags);
4296 		if (i & EXT2_FLAGS_UNSIGNED_HASH)
4297 			sbi->s_hash_unsigned = 3;
4298 		else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4299 #ifdef __CHAR_UNSIGNED__
4300 			if (!sb_rdonly(sb))
4301 				es->s_flags |=
4302 					cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4303 			sbi->s_hash_unsigned = 3;
4304 #else
4305 			if (!sb_rdonly(sb))
4306 				es->s_flags |=
4307 					cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4308 #endif
4309 		}
4310 	}
4311 
4312 	/* Handle clustersize */
4313 	clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4314 	if (ext4_has_feature_bigalloc(sb)) {
4315 		if (clustersize < blocksize) {
4316 			ext4_msg(sb, KERN_ERR,
4317 				 "cluster size (%d) smaller than "
4318 				 "block size (%d)", clustersize, blocksize);
4319 			goto failed_mount;
4320 		}
4321 		sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4322 			le32_to_cpu(es->s_log_block_size);
4323 		sbi->s_clusters_per_group =
4324 			le32_to_cpu(es->s_clusters_per_group);
4325 		if (sbi->s_clusters_per_group > blocksize * 8) {
4326 			ext4_msg(sb, KERN_ERR,
4327 				 "#clusters per group too big: %lu",
4328 				 sbi->s_clusters_per_group);
4329 			goto failed_mount;
4330 		}
4331 		if (sbi->s_blocks_per_group !=
4332 		    (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4333 			ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4334 				 "clusters per group (%lu) inconsistent",
4335 				 sbi->s_blocks_per_group,
4336 				 sbi->s_clusters_per_group);
4337 			goto failed_mount;
4338 		}
4339 	} else {
4340 		if (clustersize != blocksize) {
4341 			ext4_msg(sb, KERN_ERR,
4342 				 "fragment/cluster size (%d) != "
4343 				 "block size (%d)", clustersize, blocksize);
4344 			goto failed_mount;
4345 		}
4346 		if (sbi->s_blocks_per_group > blocksize * 8) {
4347 			ext4_msg(sb, KERN_ERR,
4348 				 "#blocks per group too big: %lu",
4349 				 sbi->s_blocks_per_group);
4350 			goto failed_mount;
4351 		}
4352 		sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4353 		sbi->s_cluster_bits = 0;
4354 	}
4355 	sbi->s_cluster_ratio = clustersize / blocksize;
4356 
4357 	/* Do we have standard group size of clustersize * 8 blocks ? */
4358 	if (sbi->s_blocks_per_group == clustersize << 3)
4359 		set_opt2(sb, STD_GROUP_SIZE);
4360 
4361 	/*
4362 	 * Test whether we have more sectors than will fit in sector_t,
4363 	 * and whether the max offset is addressable by the page cache.
4364 	 */
4365 	err = generic_check_addressable(sb->s_blocksize_bits,
4366 					ext4_blocks_count(es));
4367 	if (err) {
4368 		ext4_msg(sb, KERN_ERR, "filesystem"
4369 			 " too large to mount safely on this system");
4370 		goto failed_mount;
4371 	}
4372 
4373 	if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4374 		goto cantfind_ext4;
4375 
4376 	/* check blocks count against device size */
4377 	blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4378 	if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4379 		ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4380 		       "exceeds size of device (%llu blocks)",
4381 		       ext4_blocks_count(es), blocks_count);
4382 		goto failed_mount;
4383 	}
4384 
4385 	/*
4386 	 * It makes no sense for the first data block to be beyond the end
4387 	 * of the filesystem.
4388 	 */
4389 	if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4390 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4391 			 "block %u is beyond end of filesystem (%llu)",
4392 			 le32_to_cpu(es->s_first_data_block),
4393 			 ext4_blocks_count(es));
4394 		goto failed_mount;
4395 	}
4396 	if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4397 	    (sbi->s_cluster_ratio == 1)) {
4398 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4399 			 "block is 0 with a 1k block and cluster size");
4400 		goto failed_mount;
4401 	}
4402 
4403 	blocks_count = (ext4_blocks_count(es) -
4404 			le32_to_cpu(es->s_first_data_block) +
4405 			EXT4_BLOCKS_PER_GROUP(sb) - 1);
4406 	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4407 	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4408 		ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4409 		       "(block count %llu, first data block %u, "
4410 		       "blocks per group %lu)", blocks_count,
4411 		       ext4_blocks_count(es),
4412 		       le32_to_cpu(es->s_first_data_block),
4413 		       EXT4_BLOCKS_PER_GROUP(sb));
4414 		goto failed_mount;
4415 	}
4416 	sbi->s_groups_count = blocks_count;
4417 	sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4418 			(EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4419 	if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4420 	    le32_to_cpu(es->s_inodes_count)) {
4421 		ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4422 			 le32_to_cpu(es->s_inodes_count),
4423 			 ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4424 		ret = -EINVAL;
4425 		goto failed_mount;
4426 	}
4427 	db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4428 		   EXT4_DESC_PER_BLOCK(sb);
4429 	if (ext4_has_feature_meta_bg(sb)) {
4430 		if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4431 			ext4_msg(sb, KERN_WARNING,
4432 				 "first meta block group too large: %u "
4433 				 "(group descriptor block count %u)",
4434 				 le32_to_cpu(es->s_first_meta_bg), db_count);
4435 			goto failed_mount;
4436 		}
4437 	}
4438 	rcu_assign_pointer(sbi->s_group_desc,
4439 			   kvmalloc_array(db_count,
4440 					  sizeof(struct buffer_head *),
4441 					  GFP_KERNEL));
4442 	if (sbi->s_group_desc == NULL) {
4443 		ext4_msg(sb, KERN_ERR, "not enough memory");
4444 		ret = -ENOMEM;
4445 		goto failed_mount;
4446 	}
4447 
4448 	bgl_lock_init(sbi->s_blockgroup_lock);
4449 
4450 	/* Pre-read the descriptors into the buffer cache */
4451 	for (i = 0; i < db_count; i++) {
4452 		block = descriptor_loc(sb, logical_sb_block, i);
4453 		sb_breadahead_unmovable(sb, block);
4454 	}
4455 
4456 	for (i = 0; i < db_count; i++) {
4457 		struct buffer_head *bh;
4458 
4459 		block = descriptor_loc(sb, logical_sb_block, i);
4460 		bh = sb_bread_unmovable(sb, block);
4461 		if (!bh) {
4462 			ext4_msg(sb, KERN_ERR,
4463 			       "can't read group descriptor %d", i);
4464 			db_count = i;
4465 			goto failed_mount2;
4466 		}
4467 		rcu_read_lock();
4468 		rcu_dereference(sbi->s_group_desc)[i] = bh;
4469 		rcu_read_unlock();
4470 	}
4471 	sbi->s_gdb_count = db_count;
4472 	if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4473 		ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4474 		ret = -EFSCORRUPTED;
4475 		goto failed_mount2;
4476 	}
4477 
4478 	timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4479 
4480 	/* Register extent status tree shrinker */
4481 	if (ext4_es_register_shrinker(sbi))
4482 		goto failed_mount3;
4483 
4484 	sbi->s_stripe = ext4_get_stripe_size(sbi);
4485 	sbi->s_extent_max_zeroout_kb = 32;
4486 
4487 	/*
4488 	 * set up enough so that it can read an inode
4489 	 */
4490 	sb->s_op = &ext4_sops;
4491 	sb->s_export_op = &ext4_export_ops;
4492 	sb->s_xattr = ext4_xattr_handlers;
4493 #ifdef CONFIG_FS_ENCRYPTION
4494 	sb->s_cop = &ext4_cryptops;
4495 #endif
4496 #ifdef CONFIG_FS_VERITY
4497 	sb->s_vop = &ext4_verityops;
4498 #endif
4499 #ifdef CONFIG_QUOTA
4500 	sb->dq_op = &ext4_quota_operations;
4501 	if (ext4_has_feature_quota(sb))
4502 		sb->s_qcop = &dquot_quotactl_sysfile_ops;
4503 	else
4504 		sb->s_qcop = &ext4_qctl_operations;
4505 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4506 #endif
4507 	memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4508 
4509 	INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4510 	mutex_init(&sbi->s_orphan_lock);
4511 
4512 	sb->s_root = NULL;
4513 
4514 	needs_recovery = (es->s_last_orphan != 0 ||
4515 			  ext4_has_feature_journal_needs_recovery(sb));
4516 
4517 	if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4518 		if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4519 			goto failed_mount3a;
4520 
4521 	/*
4522 	 * The first inode we look at is the journal inode.  Don't try
4523 	 * root first: it may be modified in the journal!
4524 	 */
4525 	if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4526 		err = ext4_load_journal(sb, es, journal_devnum);
4527 		if (err)
4528 			goto failed_mount3a;
4529 	} else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4530 		   ext4_has_feature_journal_needs_recovery(sb)) {
4531 		ext4_msg(sb, KERN_ERR, "required journal recovery "
4532 		       "suppressed and not mounted read-only");
4533 		goto failed_mount_wq;
4534 	} else {
4535 		/* Nojournal mode, all journal mount options are illegal */
4536 		if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4537 			ext4_msg(sb, KERN_ERR, "can't mount with "
4538 				 "journal_checksum, fs mounted w/o journal");
4539 			goto failed_mount_wq;
4540 		}
4541 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4542 			ext4_msg(sb, KERN_ERR, "can't mount with "
4543 				 "journal_async_commit, fs mounted w/o journal");
4544 			goto failed_mount_wq;
4545 		}
4546 		if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4547 			ext4_msg(sb, KERN_ERR, "can't mount with "
4548 				 "commit=%lu, fs mounted w/o journal",
4549 				 sbi->s_commit_interval / HZ);
4550 			goto failed_mount_wq;
4551 		}
4552 		if (EXT4_MOUNT_DATA_FLAGS &
4553 		    (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4554 			ext4_msg(sb, KERN_ERR, "can't mount with "
4555 				 "data=, fs mounted w/o journal");
4556 			goto failed_mount_wq;
4557 		}
4558 		sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4559 		clear_opt(sb, JOURNAL_CHECKSUM);
4560 		clear_opt(sb, DATA_FLAGS);
4561 		sbi->s_journal = NULL;
4562 		needs_recovery = 0;
4563 		goto no_journal;
4564 	}
4565 
4566 	if (ext4_has_feature_64bit(sb) &&
4567 	    !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4568 				       JBD2_FEATURE_INCOMPAT_64BIT)) {
4569 		ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4570 		goto failed_mount_wq;
4571 	}
4572 
4573 	if (!set_journal_csum_feature_set(sb)) {
4574 		ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4575 			 "feature set");
4576 		goto failed_mount_wq;
4577 	}
4578 
4579 	/* We have now updated the journal if required, so we can
4580 	 * validate the data journaling mode. */
4581 	switch (test_opt(sb, DATA_FLAGS)) {
4582 	case 0:
4583 		/* No mode set, assume a default based on the journal
4584 		 * capabilities: ORDERED_DATA if the journal can
4585 		 * cope, else JOURNAL_DATA
4586 		 */
4587 		if (jbd2_journal_check_available_features
4588 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4589 			set_opt(sb, ORDERED_DATA);
4590 			sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4591 		} else {
4592 			set_opt(sb, JOURNAL_DATA);
4593 			sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4594 		}
4595 		break;
4596 
4597 	case EXT4_MOUNT_ORDERED_DATA:
4598 	case EXT4_MOUNT_WRITEBACK_DATA:
4599 		if (!jbd2_journal_check_available_features
4600 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4601 			ext4_msg(sb, KERN_ERR, "Journal does not support "
4602 			       "requested data journaling mode");
4603 			goto failed_mount_wq;
4604 		}
4605 	default:
4606 		break;
4607 	}
4608 
4609 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4610 	    test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4611 		ext4_msg(sb, KERN_ERR, "can't mount with "
4612 			"journal_async_commit in data=ordered mode");
4613 		goto failed_mount_wq;
4614 	}
4615 
4616 	set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4617 
4618 	sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4619 
4620 no_journal:
4621 	if (!test_opt(sb, NO_MBCACHE)) {
4622 		sbi->s_ea_block_cache = ext4_xattr_create_cache();
4623 		if (!sbi->s_ea_block_cache) {
4624 			ext4_msg(sb, KERN_ERR,
4625 				 "Failed to create ea_block_cache");
4626 			goto failed_mount_wq;
4627 		}
4628 
4629 		if (ext4_has_feature_ea_inode(sb)) {
4630 			sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4631 			if (!sbi->s_ea_inode_cache) {
4632 				ext4_msg(sb, KERN_ERR,
4633 					 "Failed to create ea_inode_cache");
4634 				goto failed_mount_wq;
4635 			}
4636 		}
4637 	}
4638 
4639 	if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4640 		ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4641 		goto failed_mount_wq;
4642 	}
4643 
4644 	if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4645 	    !ext4_has_feature_encrypt(sb)) {
4646 		ext4_set_feature_encrypt(sb);
4647 		ext4_commit_super(sb, 1);
4648 	}
4649 
4650 	/*
4651 	 * Get the # of file system overhead blocks from the
4652 	 * superblock if present.
4653 	 */
4654 	if (es->s_overhead_clusters)
4655 		sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4656 	else {
4657 		err = ext4_calculate_overhead(sb);
4658 		if (err)
4659 			goto failed_mount_wq;
4660 	}
4661 
4662 	/*
4663 	 * The maximum number of concurrent works can be high and
4664 	 * concurrency isn't really necessary.  Limit it to 1.
4665 	 */
4666 	EXT4_SB(sb)->rsv_conversion_wq =
4667 		alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4668 	if (!EXT4_SB(sb)->rsv_conversion_wq) {
4669 		printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4670 		ret = -ENOMEM;
4671 		goto failed_mount4;
4672 	}
4673 
4674 	/*
4675 	 * The jbd2_journal_load will have done any necessary log recovery,
4676 	 * so we can safely mount the rest of the filesystem now.
4677 	 */
4678 
4679 	root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4680 	if (IS_ERR(root)) {
4681 		ext4_msg(sb, KERN_ERR, "get root inode failed");
4682 		ret = PTR_ERR(root);
4683 		root = NULL;
4684 		goto failed_mount4;
4685 	}
4686 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4687 		ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4688 		iput(root);
4689 		goto failed_mount4;
4690 	}
4691 
4692 #ifdef CONFIG_UNICODE
4693 	if (sbi->s_encoding)
4694 		sb->s_d_op = &ext4_dentry_ops;
4695 #endif
4696 
4697 	sb->s_root = d_make_root(root);
4698 	if (!sb->s_root) {
4699 		ext4_msg(sb, KERN_ERR, "get root dentry failed");
4700 		ret = -ENOMEM;
4701 		goto failed_mount4;
4702 	}
4703 
4704 	ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4705 	if (ret == -EROFS) {
4706 		sb->s_flags |= SB_RDONLY;
4707 		ret = 0;
4708 	} else if (ret)
4709 		goto failed_mount4a;
4710 
4711 	ext4_set_resv_clusters(sb);
4712 
4713 	err = ext4_setup_system_zone(sb);
4714 	if (err) {
4715 		ext4_msg(sb, KERN_ERR, "failed to initialize system "
4716 			 "zone (%d)", err);
4717 		goto failed_mount4a;
4718 	}
4719 
4720 	ext4_ext_init(sb);
4721 	err = ext4_mb_init(sb);
4722 	if (err) {
4723 		ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4724 			 err);
4725 		goto failed_mount5;
4726 	}
4727 
4728 	block = ext4_count_free_clusters(sb);
4729 	ext4_free_blocks_count_set(sbi->s_es,
4730 				   EXT4_C2B(sbi, block));
4731 	ext4_superblock_csum_set(sb);
4732 	err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4733 				  GFP_KERNEL);
4734 	if (!err) {
4735 		unsigned long freei = ext4_count_free_inodes(sb);
4736 		sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4737 		ext4_superblock_csum_set(sb);
4738 		err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4739 					  GFP_KERNEL);
4740 	}
4741 	if (!err)
4742 		err = percpu_counter_init(&sbi->s_dirs_counter,
4743 					  ext4_count_dirs(sb), GFP_KERNEL);
4744 	if (!err)
4745 		err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4746 					  GFP_KERNEL);
4747 	if (!err)
4748 		err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4749 
4750 	if (err) {
4751 		ext4_msg(sb, KERN_ERR, "insufficient memory");
4752 		goto failed_mount6;
4753 	}
4754 
4755 	if (ext4_has_feature_flex_bg(sb))
4756 		if (!ext4_fill_flex_info(sb)) {
4757 			ext4_msg(sb, KERN_ERR,
4758 			       "unable to initialize "
4759 			       "flex_bg meta info!");
4760 			goto failed_mount6;
4761 		}
4762 
4763 	err = ext4_register_li_request(sb, first_not_zeroed);
4764 	if (err)
4765 		goto failed_mount6;
4766 
4767 	err = ext4_register_sysfs(sb);
4768 	if (err)
4769 		goto failed_mount7;
4770 
4771 #ifdef CONFIG_QUOTA
4772 	/* Enable quota usage during mount. */
4773 	if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4774 		err = ext4_enable_quotas(sb);
4775 		if (err)
4776 			goto failed_mount8;
4777 	}
4778 #endif  /* CONFIG_QUOTA */
4779 
4780 	EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4781 	ext4_orphan_cleanup(sb, es);
4782 	EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4783 	if (needs_recovery) {
4784 		ext4_msg(sb, KERN_INFO, "recovery complete");
4785 		ext4_mark_recovery_complete(sb, es);
4786 	}
4787 	if (EXT4_SB(sb)->s_journal) {
4788 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4789 			descr = " journalled data mode";
4790 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4791 			descr = " ordered data mode";
4792 		else
4793 			descr = " writeback data mode";
4794 	} else
4795 		descr = "out journal";
4796 
4797 	if (test_opt(sb, DISCARD)) {
4798 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
4799 		if (!blk_queue_discard(q))
4800 			ext4_msg(sb, KERN_WARNING,
4801 				 "mounting with \"discard\" option, but "
4802 				 "the device does not support discard");
4803 	}
4804 
4805 	if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4806 		ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4807 			 "Opts: %.*s%s%s", descr,
4808 			 (int) sizeof(sbi->s_es->s_mount_opts),
4809 			 sbi->s_es->s_mount_opts,
4810 			 *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4811 
4812 	if (es->s_error_count)
4813 		mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4814 
4815 	/* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4816 	ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4817 	ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4818 	ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4819 
4820 	kfree(orig_data);
4821 	return 0;
4822 
4823 cantfind_ext4:
4824 	if (!silent)
4825 		ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4826 	goto failed_mount;
4827 
4828 #ifdef CONFIG_QUOTA
4829 failed_mount8:
4830 	ext4_unregister_sysfs(sb);
4831 #endif
4832 failed_mount7:
4833 	ext4_unregister_li_request(sb);
4834 failed_mount6:
4835 	ext4_mb_release(sb);
4836 	rcu_read_lock();
4837 	flex_groups = rcu_dereference(sbi->s_flex_groups);
4838 	if (flex_groups) {
4839 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
4840 			kvfree(flex_groups[i]);
4841 		kvfree(flex_groups);
4842 	}
4843 	rcu_read_unlock();
4844 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
4845 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
4846 	percpu_counter_destroy(&sbi->s_dirs_counter);
4847 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4848 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
4849 failed_mount5:
4850 	ext4_ext_release(sb);
4851 	ext4_release_system_zone(sb);
4852 failed_mount4a:
4853 	dput(sb->s_root);
4854 	sb->s_root = NULL;
4855 failed_mount4:
4856 	ext4_msg(sb, KERN_ERR, "mount failed");
4857 	if (EXT4_SB(sb)->rsv_conversion_wq)
4858 		destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4859 failed_mount_wq:
4860 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4861 	sbi->s_ea_inode_cache = NULL;
4862 
4863 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4864 	sbi->s_ea_block_cache = NULL;
4865 
4866 	if (sbi->s_journal) {
4867 		jbd2_journal_destroy(sbi->s_journal);
4868 		sbi->s_journal = NULL;
4869 	}
4870 failed_mount3a:
4871 	ext4_es_unregister_shrinker(sbi);
4872 failed_mount3:
4873 	del_timer_sync(&sbi->s_err_report);
4874 	if (sbi->s_mmp_tsk)
4875 		kthread_stop(sbi->s_mmp_tsk);
4876 failed_mount2:
4877 	rcu_read_lock();
4878 	group_desc = rcu_dereference(sbi->s_group_desc);
4879 	for (i = 0; i < db_count; i++)
4880 		brelse(group_desc[i]);
4881 	kvfree(group_desc);
4882 	rcu_read_unlock();
4883 failed_mount:
4884 	if (sbi->s_chksum_driver)
4885 		crypto_free_shash(sbi->s_chksum_driver);
4886 
4887 #ifdef CONFIG_UNICODE
4888 	utf8_unload(sbi->s_encoding);
4889 #endif
4890 
4891 #ifdef CONFIG_QUOTA
4892 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
4893 		kfree(get_qf_name(sb, sbi, i));
4894 #endif
4895 	fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
4896 	ext4_blkdev_remove(sbi);
4897 	brelse(bh);
4898 out_fail:
4899 	sb->s_fs_info = NULL;
4900 	kfree(sbi->s_blockgroup_lock);
4901 out_free_base:
4902 	kfree(sbi);
4903 	kfree(orig_data);
4904 	fs_put_dax(dax_dev);
4905 	return err ? err : ret;
4906 }
4907 
4908 /*
4909  * Setup any per-fs journal parameters now.  We'll do this both on
4910  * initial mount, once the journal has been initialised but before we've
4911  * done any recovery; and again on any subsequent remount.
4912  */
4913 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4914 {
4915 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4916 
4917 	journal->j_commit_interval = sbi->s_commit_interval;
4918 	journal->j_min_batch_time = sbi->s_min_batch_time;
4919 	journal->j_max_batch_time = sbi->s_max_batch_time;
4920 
4921 	write_lock(&journal->j_state_lock);
4922 	if (test_opt(sb, BARRIER))
4923 		journal->j_flags |= JBD2_BARRIER;
4924 	else
4925 		journal->j_flags &= ~JBD2_BARRIER;
4926 	if (test_opt(sb, DATA_ERR_ABORT))
4927 		journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4928 	else
4929 		journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4930 	write_unlock(&journal->j_state_lock);
4931 }
4932 
4933 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4934 					     unsigned int journal_inum)
4935 {
4936 	struct inode *journal_inode;
4937 
4938 	/*
4939 	 * Test for the existence of a valid inode on disk.  Bad things
4940 	 * happen if we iget() an unused inode, as the subsequent iput()
4941 	 * will try to delete it.
4942 	 */
4943 	journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4944 	if (IS_ERR(journal_inode)) {
4945 		ext4_msg(sb, KERN_ERR, "no journal found");
4946 		return NULL;
4947 	}
4948 	if (!journal_inode->i_nlink) {
4949 		make_bad_inode(journal_inode);
4950 		iput(journal_inode);
4951 		ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4952 		return NULL;
4953 	}
4954 
4955 	jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4956 		  journal_inode, journal_inode->i_size);
4957 	if (!S_ISREG(journal_inode->i_mode)) {
4958 		ext4_msg(sb, KERN_ERR, "invalid journal inode");
4959 		iput(journal_inode);
4960 		return NULL;
4961 	}
4962 	return journal_inode;
4963 }
4964 
4965 static journal_t *ext4_get_journal(struct super_block *sb,
4966 				   unsigned int journal_inum)
4967 {
4968 	struct inode *journal_inode;
4969 	journal_t *journal;
4970 
4971 	BUG_ON(!ext4_has_feature_journal(sb));
4972 
4973 	journal_inode = ext4_get_journal_inode(sb, journal_inum);
4974 	if (!journal_inode)
4975 		return NULL;
4976 
4977 	journal = jbd2_journal_init_inode(journal_inode);
4978 	if (!journal) {
4979 		ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4980 		iput(journal_inode);
4981 		return NULL;
4982 	}
4983 	journal->j_private = sb;
4984 	ext4_init_journal_params(sb, journal);
4985 	return journal;
4986 }
4987 
4988 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4989 				       dev_t j_dev)
4990 {
4991 	struct buffer_head *bh;
4992 	journal_t *journal;
4993 	ext4_fsblk_t start;
4994 	ext4_fsblk_t len;
4995 	int hblock, blocksize;
4996 	ext4_fsblk_t sb_block;
4997 	unsigned long offset;
4998 	struct ext4_super_block *es;
4999 	struct block_device *bdev;
5000 
5001 	BUG_ON(!ext4_has_feature_journal(sb));
5002 
5003 	bdev = ext4_blkdev_get(j_dev, sb);
5004 	if (bdev == NULL)
5005 		return NULL;
5006 
5007 	blocksize = sb->s_blocksize;
5008 	hblock = bdev_logical_block_size(bdev);
5009 	if (blocksize < hblock) {
5010 		ext4_msg(sb, KERN_ERR,
5011 			"blocksize too small for journal device");
5012 		goto out_bdev;
5013 	}
5014 
5015 	sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5016 	offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5017 	set_blocksize(bdev, blocksize);
5018 	if (!(bh = __bread(bdev, sb_block, blocksize))) {
5019 		ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5020 		       "external journal");
5021 		goto out_bdev;
5022 	}
5023 
5024 	es = (struct ext4_super_block *) (bh->b_data + offset);
5025 	if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5026 	    !(le32_to_cpu(es->s_feature_incompat) &
5027 	      EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5028 		ext4_msg(sb, KERN_ERR, "external journal has "
5029 					"bad superblock");
5030 		brelse(bh);
5031 		goto out_bdev;
5032 	}
5033 
5034 	if ((le32_to_cpu(es->s_feature_ro_compat) &
5035 	     EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5036 	    es->s_checksum != ext4_superblock_csum(sb, es)) {
5037 		ext4_msg(sb, KERN_ERR, "external journal has "
5038 				       "corrupt superblock");
5039 		brelse(bh);
5040 		goto out_bdev;
5041 	}
5042 
5043 	if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5044 		ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5045 		brelse(bh);
5046 		goto out_bdev;
5047 	}
5048 
5049 	len = ext4_blocks_count(es);
5050 	start = sb_block + 1;
5051 	brelse(bh);	/* we're done with the superblock */
5052 
5053 	journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5054 					start, len, blocksize);
5055 	if (!journal) {
5056 		ext4_msg(sb, KERN_ERR, "failed to create device journal");
5057 		goto out_bdev;
5058 	}
5059 	journal->j_private = sb;
5060 	ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
5061 	wait_on_buffer(journal->j_sb_buffer);
5062 	if (!buffer_uptodate(journal->j_sb_buffer)) {
5063 		ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5064 		goto out_journal;
5065 	}
5066 	if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5067 		ext4_msg(sb, KERN_ERR, "External journal has more than one "
5068 					"user (unsupported) - %d",
5069 			be32_to_cpu(journal->j_superblock->s_nr_users));
5070 		goto out_journal;
5071 	}
5072 	EXT4_SB(sb)->journal_bdev = bdev;
5073 	ext4_init_journal_params(sb, journal);
5074 	return journal;
5075 
5076 out_journal:
5077 	jbd2_journal_destroy(journal);
5078 out_bdev:
5079 	ext4_blkdev_put(bdev);
5080 	return NULL;
5081 }
5082 
5083 static int ext4_load_journal(struct super_block *sb,
5084 			     struct ext4_super_block *es,
5085 			     unsigned long journal_devnum)
5086 {
5087 	journal_t *journal;
5088 	unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5089 	dev_t journal_dev;
5090 	int err = 0;
5091 	int really_read_only;
5092 
5093 	BUG_ON(!ext4_has_feature_journal(sb));
5094 
5095 	if (journal_devnum &&
5096 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5097 		ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5098 			"numbers have changed");
5099 		journal_dev = new_decode_dev(journal_devnum);
5100 	} else
5101 		journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5102 
5103 	really_read_only = bdev_read_only(sb->s_bdev);
5104 
5105 	/*
5106 	 * Are we loading a blank journal or performing recovery after a
5107 	 * crash?  For recovery, we need to check in advance whether we
5108 	 * can get read-write access to the device.
5109 	 */
5110 	if (ext4_has_feature_journal_needs_recovery(sb)) {
5111 		if (sb_rdonly(sb)) {
5112 			ext4_msg(sb, KERN_INFO, "INFO: recovery "
5113 					"required on readonly filesystem");
5114 			if (really_read_only) {
5115 				ext4_msg(sb, KERN_ERR, "write access "
5116 					"unavailable, cannot proceed "
5117 					"(try mounting with noload)");
5118 				return -EROFS;
5119 			}
5120 			ext4_msg(sb, KERN_INFO, "write access will "
5121 			       "be enabled during recovery");
5122 		}
5123 	}
5124 
5125 	if (journal_inum && journal_dev) {
5126 		ext4_msg(sb, KERN_ERR, "filesystem has both journal "
5127 		       "and inode journals!");
5128 		return -EINVAL;
5129 	}
5130 
5131 	if (journal_inum) {
5132 		if (!(journal = ext4_get_journal(sb, journal_inum)))
5133 			return -EINVAL;
5134 	} else {
5135 		if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
5136 			return -EINVAL;
5137 	}
5138 
5139 	if (!(journal->j_flags & JBD2_BARRIER))
5140 		ext4_msg(sb, KERN_INFO, "barriers disabled");
5141 
5142 	if (!ext4_has_feature_journal_needs_recovery(sb))
5143 		err = jbd2_journal_wipe(journal, !really_read_only);
5144 	if (!err) {
5145 		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5146 		if (save)
5147 			memcpy(save, ((char *) es) +
5148 			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5149 		err = jbd2_journal_load(journal);
5150 		if (save)
5151 			memcpy(((char *) es) + EXT4_S_ERR_START,
5152 			       save, EXT4_S_ERR_LEN);
5153 		kfree(save);
5154 	}
5155 
5156 	if (err) {
5157 		ext4_msg(sb, KERN_ERR, "error loading journal");
5158 		jbd2_journal_destroy(journal);
5159 		return err;
5160 	}
5161 
5162 	EXT4_SB(sb)->s_journal = journal;
5163 	ext4_clear_journal_err(sb, es);
5164 
5165 	if (!really_read_only && journal_devnum &&
5166 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5167 		es->s_journal_dev = cpu_to_le32(journal_devnum);
5168 
5169 		/* Make sure we flush the recovery flag to disk. */
5170 		ext4_commit_super(sb, 1);
5171 	}
5172 
5173 	return 0;
5174 }
5175 
5176 static int ext4_commit_super(struct super_block *sb, int sync)
5177 {
5178 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5179 	struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5180 	int error = 0;
5181 
5182 	if (!sbh || block_device_ejected(sb))
5183 		return error;
5184 
5185 	/*
5186 	 * The superblock bh should be mapped, but it might not be if the
5187 	 * device was hot-removed. Not much we can do but fail the I/O.
5188 	 */
5189 	if (!buffer_mapped(sbh))
5190 		return error;
5191 
5192 	/*
5193 	 * If the file system is mounted read-only, don't update the
5194 	 * superblock write time.  This avoids updating the superblock
5195 	 * write time when we are mounting the root file system
5196 	 * read/only but we need to replay the journal; at that point,
5197 	 * for people who are east of GMT and who make their clock
5198 	 * tick in localtime for Windows bug-for-bug compatibility,
5199 	 * the clock is set in the future, and this will cause e2fsck
5200 	 * to complain and force a full file system check.
5201 	 */
5202 	if (!(sb->s_flags & SB_RDONLY))
5203 		ext4_update_tstamp(es, s_wtime);
5204 	if (sb->s_bdev->bd_part)
5205 		es->s_kbytes_written =
5206 			cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5207 			    ((part_stat_read(sb->s_bdev->bd_part,
5208 					     sectors[STAT_WRITE]) -
5209 			      EXT4_SB(sb)->s_sectors_written_start) >> 1));
5210 	else
5211 		es->s_kbytes_written =
5212 			cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5213 	if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5214 		ext4_free_blocks_count_set(es,
5215 			EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5216 				&EXT4_SB(sb)->s_freeclusters_counter)));
5217 	if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5218 		es->s_free_inodes_count =
5219 			cpu_to_le32(percpu_counter_sum_positive(
5220 				&EXT4_SB(sb)->s_freeinodes_counter));
5221 	BUFFER_TRACE(sbh, "marking dirty");
5222 	ext4_superblock_csum_set(sb);
5223 	if (sync)
5224 		lock_buffer(sbh);
5225 	if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5226 		/*
5227 		 * Oh, dear.  A previous attempt to write the
5228 		 * superblock failed.  This could happen because the
5229 		 * USB device was yanked out.  Or it could happen to
5230 		 * be a transient write error and maybe the block will
5231 		 * be remapped.  Nothing we can do but to retry the
5232 		 * write and hope for the best.
5233 		 */
5234 		ext4_msg(sb, KERN_ERR, "previous I/O error to "
5235 		       "superblock detected");
5236 		clear_buffer_write_io_error(sbh);
5237 		set_buffer_uptodate(sbh);
5238 	}
5239 	mark_buffer_dirty(sbh);
5240 	if (sync) {
5241 		unlock_buffer(sbh);
5242 		error = __sync_dirty_buffer(sbh,
5243 			REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5244 		if (buffer_write_io_error(sbh)) {
5245 			ext4_msg(sb, KERN_ERR, "I/O error while writing "
5246 			       "superblock");
5247 			clear_buffer_write_io_error(sbh);
5248 			set_buffer_uptodate(sbh);
5249 		}
5250 	}
5251 	return error;
5252 }
5253 
5254 /*
5255  * Have we just finished recovery?  If so, and if we are mounting (or
5256  * remounting) the filesystem readonly, then we will end up with a
5257  * consistent fs on disk.  Record that fact.
5258  */
5259 static void ext4_mark_recovery_complete(struct super_block *sb,
5260 					struct ext4_super_block *es)
5261 {
5262 	journal_t *journal = EXT4_SB(sb)->s_journal;
5263 
5264 	if (!ext4_has_feature_journal(sb)) {
5265 		BUG_ON(journal != NULL);
5266 		return;
5267 	}
5268 	jbd2_journal_lock_updates(journal);
5269 	if (jbd2_journal_flush(journal) < 0)
5270 		goto out;
5271 
5272 	if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5273 		ext4_clear_feature_journal_needs_recovery(sb);
5274 		ext4_commit_super(sb, 1);
5275 	}
5276 
5277 out:
5278 	jbd2_journal_unlock_updates(journal);
5279 }
5280 
5281 /*
5282  * If we are mounting (or read-write remounting) a filesystem whose journal
5283  * has recorded an error from a previous lifetime, move that error to the
5284  * main filesystem now.
5285  */
5286 static void ext4_clear_journal_err(struct super_block *sb,
5287 				   struct ext4_super_block *es)
5288 {
5289 	journal_t *journal;
5290 	int j_errno;
5291 	const char *errstr;
5292 
5293 	BUG_ON(!ext4_has_feature_journal(sb));
5294 
5295 	journal = EXT4_SB(sb)->s_journal;
5296 
5297 	/*
5298 	 * Now check for any error status which may have been recorded in the
5299 	 * journal by a prior ext4_error() or ext4_abort()
5300 	 */
5301 
5302 	j_errno = jbd2_journal_errno(journal);
5303 	if (j_errno) {
5304 		char nbuf[16];
5305 
5306 		errstr = ext4_decode_error(sb, j_errno, nbuf);
5307 		ext4_warning(sb, "Filesystem error recorded "
5308 			     "from previous mount: %s", errstr);
5309 		ext4_warning(sb, "Marking fs in need of filesystem check.");
5310 
5311 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5312 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5313 		ext4_commit_super(sb, 1);
5314 
5315 		jbd2_journal_clear_err(journal);
5316 		jbd2_journal_update_sb_errno(journal);
5317 	}
5318 }
5319 
5320 /*
5321  * Force the running and committing transactions to commit,
5322  * and wait on the commit.
5323  */
5324 int ext4_force_commit(struct super_block *sb)
5325 {
5326 	journal_t *journal;
5327 
5328 	if (sb_rdonly(sb))
5329 		return 0;
5330 
5331 	journal = EXT4_SB(sb)->s_journal;
5332 	return ext4_journal_force_commit(journal);
5333 }
5334 
5335 static int ext4_sync_fs(struct super_block *sb, int wait)
5336 {
5337 	int ret = 0;
5338 	tid_t target;
5339 	bool needs_barrier = false;
5340 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5341 
5342 	if (unlikely(ext4_forced_shutdown(sbi)))
5343 		return 0;
5344 
5345 	trace_ext4_sync_fs(sb, wait);
5346 	flush_workqueue(sbi->rsv_conversion_wq);
5347 	/*
5348 	 * Writeback quota in non-journalled quota case - journalled quota has
5349 	 * no dirty dquots
5350 	 */
5351 	dquot_writeback_dquots(sb, -1);
5352 	/*
5353 	 * Data writeback is possible w/o journal transaction, so barrier must
5354 	 * being sent at the end of the function. But we can skip it if
5355 	 * transaction_commit will do it for us.
5356 	 */
5357 	if (sbi->s_journal) {
5358 		target = jbd2_get_latest_transaction(sbi->s_journal);
5359 		if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5360 		    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5361 			needs_barrier = true;
5362 
5363 		if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5364 			if (wait)
5365 				ret = jbd2_log_wait_commit(sbi->s_journal,
5366 							   target);
5367 		}
5368 	} else if (wait && test_opt(sb, BARRIER))
5369 		needs_barrier = true;
5370 	if (needs_barrier) {
5371 		int err;
5372 		err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
5373 		if (!ret)
5374 			ret = err;
5375 	}
5376 
5377 	return ret;
5378 }
5379 
5380 /*
5381  * LVM calls this function before a (read-only) snapshot is created.  This
5382  * gives us a chance to flush the journal completely and mark the fs clean.
5383  *
5384  * Note that only this function cannot bring a filesystem to be in a clean
5385  * state independently. It relies on upper layer to stop all data & metadata
5386  * modifications.
5387  */
5388 static int ext4_freeze(struct super_block *sb)
5389 {
5390 	int error = 0;
5391 	journal_t *journal;
5392 
5393 	if (sb_rdonly(sb))
5394 		return 0;
5395 
5396 	journal = EXT4_SB(sb)->s_journal;
5397 
5398 	if (journal) {
5399 		/* Now we set up the journal barrier. */
5400 		jbd2_journal_lock_updates(journal);
5401 
5402 		/*
5403 		 * Don't clear the needs_recovery flag if we failed to
5404 		 * flush the journal.
5405 		 */
5406 		error = jbd2_journal_flush(journal);
5407 		if (error < 0)
5408 			goto out;
5409 
5410 		/* Journal blocked and flushed, clear needs_recovery flag. */
5411 		ext4_clear_feature_journal_needs_recovery(sb);
5412 	}
5413 
5414 	error = ext4_commit_super(sb, 1);
5415 out:
5416 	if (journal)
5417 		/* we rely on upper layer to stop further updates */
5418 		jbd2_journal_unlock_updates(journal);
5419 	return error;
5420 }
5421 
5422 /*
5423  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5424  * flag here, even though the filesystem is not technically dirty yet.
5425  */
5426 static int ext4_unfreeze(struct super_block *sb)
5427 {
5428 	if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5429 		return 0;
5430 
5431 	if (EXT4_SB(sb)->s_journal) {
5432 		/* Reset the needs_recovery flag before the fs is unlocked. */
5433 		ext4_set_feature_journal_needs_recovery(sb);
5434 	}
5435 
5436 	ext4_commit_super(sb, 1);
5437 	return 0;
5438 }
5439 
5440 /*
5441  * Structure to save mount options for ext4_remount's benefit
5442  */
5443 struct ext4_mount_options {
5444 	unsigned long s_mount_opt;
5445 	unsigned long s_mount_opt2;
5446 	kuid_t s_resuid;
5447 	kgid_t s_resgid;
5448 	unsigned long s_commit_interval;
5449 	u32 s_min_batch_time, s_max_batch_time;
5450 #ifdef CONFIG_QUOTA
5451 	int s_jquota_fmt;
5452 	char *s_qf_names[EXT4_MAXQUOTAS];
5453 #endif
5454 };
5455 
5456 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5457 {
5458 	struct ext4_super_block *es;
5459 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5460 	unsigned long old_sb_flags;
5461 	struct ext4_mount_options old_opts;
5462 	int enable_quota = 0;
5463 	ext4_group_t g;
5464 	unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5465 	int err = 0;
5466 #ifdef CONFIG_QUOTA
5467 	int i, j;
5468 	char *to_free[EXT4_MAXQUOTAS];
5469 #endif
5470 	char *orig_data = kstrdup(data, GFP_KERNEL);
5471 
5472 	if (data && !orig_data)
5473 		return -ENOMEM;
5474 
5475 	/* Store the original options */
5476 	old_sb_flags = sb->s_flags;
5477 	old_opts.s_mount_opt = sbi->s_mount_opt;
5478 	old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5479 	old_opts.s_resuid = sbi->s_resuid;
5480 	old_opts.s_resgid = sbi->s_resgid;
5481 	old_opts.s_commit_interval = sbi->s_commit_interval;
5482 	old_opts.s_min_batch_time = sbi->s_min_batch_time;
5483 	old_opts.s_max_batch_time = sbi->s_max_batch_time;
5484 #ifdef CONFIG_QUOTA
5485 	old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5486 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5487 		if (sbi->s_qf_names[i]) {
5488 			char *qf_name = get_qf_name(sb, sbi, i);
5489 
5490 			old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5491 			if (!old_opts.s_qf_names[i]) {
5492 				for (j = 0; j < i; j++)
5493 					kfree(old_opts.s_qf_names[j]);
5494 				kfree(orig_data);
5495 				return -ENOMEM;
5496 			}
5497 		} else
5498 			old_opts.s_qf_names[i] = NULL;
5499 #endif
5500 	if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5501 		journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5502 
5503 	if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5504 		err = -EINVAL;
5505 		goto restore_opts;
5506 	}
5507 
5508 	if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5509 	    test_opt(sb, JOURNAL_CHECKSUM)) {
5510 		ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5511 			 "during remount not supported; ignoring");
5512 		sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5513 	}
5514 
5515 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5516 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5517 			ext4_msg(sb, KERN_ERR, "can't mount with "
5518 				 "both data=journal and delalloc");
5519 			err = -EINVAL;
5520 			goto restore_opts;
5521 		}
5522 		if (test_opt(sb, DIOREAD_NOLOCK)) {
5523 			ext4_msg(sb, KERN_ERR, "can't mount with "
5524 				 "both data=journal and dioread_nolock");
5525 			err = -EINVAL;
5526 			goto restore_opts;
5527 		}
5528 	} else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5529 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5530 			ext4_msg(sb, KERN_ERR, "can't mount with "
5531 				"journal_async_commit in data=ordered mode");
5532 			err = -EINVAL;
5533 			goto restore_opts;
5534 		}
5535 	}
5536 
5537 	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5538 		ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5539 		err = -EINVAL;
5540 		goto restore_opts;
5541 	}
5542 
5543 	if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5544 		ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5545 
5546 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5547 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5548 
5549 	es = sbi->s_es;
5550 
5551 	if (sbi->s_journal) {
5552 		ext4_init_journal_params(sb, sbi->s_journal);
5553 		set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5554 	}
5555 
5556 	if (*flags & SB_LAZYTIME)
5557 		sb->s_flags |= SB_LAZYTIME;
5558 
5559 	if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5560 		if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5561 			err = -EROFS;
5562 			goto restore_opts;
5563 		}
5564 
5565 		if (*flags & SB_RDONLY) {
5566 			err = sync_filesystem(sb);
5567 			if (err < 0)
5568 				goto restore_opts;
5569 			err = dquot_suspend(sb, -1);
5570 			if (err < 0)
5571 				goto restore_opts;
5572 
5573 			/*
5574 			 * First of all, the unconditional stuff we have to do
5575 			 * to disable replay of the journal when we next remount
5576 			 */
5577 			sb->s_flags |= SB_RDONLY;
5578 
5579 			/*
5580 			 * OK, test if we are remounting a valid rw partition
5581 			 * readonly, and if so set the rdonly flag and then
5582 			 * mark the partition as valid again.
5583 			 */
5584 			if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5585 			    (sbi->s_mount_state & EXT4_VALID_FS))
5586 				es->s_state = cpu_to_le16(sbi->s_mount_state);
5587 
5588 			if (sbi->s_journal)
5589 				ext4_mark_recovery_complete(sb, es);
5590 			if (sbi->s_mmp_tsk)
5591 				kthread_stop(sbi->s_mmp_tsk);
5592 		} else {
5593 			/* Make sure we can mount this feature set readwrite */
5594 			if (ext4_has_feature_readonly(sb) ||
5595 			    !ext4_feature_set_ok(sb, 0)) {
5596 				err = -EROFS;
5597 				goto restore_opts;
5598 			}
5599 			/*
5600 			 * Make sure the group descriptor checksums
5601 			 * are sane.  If they aren't, refuse to remount r/w.
5602 			 */
5603 			for (g = 0; g < sbi->s_groups_count; g++) {
5604 				struct ext4_group_desc *gdp =
5605 					ext4_get_group_desc(sb, g, NULL);
5606 
5607 				if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5608 					ext4_msg(sb, KERN_ERR,
5609 	       "ext4_remount: Checksum for group %u failed (%u!=%u)",
5610 		g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5611 					       le16_to_cpu(gdp->bg_checksum));
5612 					err = -EFSBADCRC;
5613 					goto restore_opts;
5614 				}
5615 			}
5616 
5617 			/*
5618 			 * If we have an unprocessed orphan list hanging
5619 			 * around from a previously readonly bdev mount,
5620 			 * require a full umount/remount for now.
5621 			 */
5622 			if (es->s_last_orphan) {
5623 				ext4_msg(sb, KERN_WARNING, "Couldn't "
5624 				       "remount RDWR because of unprocessed "
5625 				       "orphan inode list.  Please "
5626 				       "umount/remount instead");
5627 				err = -EINVAL;
5628 				goto restore_opts;
5629 			}
5630 
5631 			/*
5632 			 * Mounting a RDONLY partition read-write, so reread
5633 			 * and store the current valid flag.  (It may have
5634 			 * been changed by e2fsck since we originally mounted
5635 			 * the partition.)
5636 			 */
5637 			if (sbi->s_journal)
5638 				ext4_clear_journal_err(sb, es);
5639 			sbi->s_mount_state = le16_to_cpu(es->s_state);
5640 
5641 			err = ext4_setup_super(sb, es, 0);
5642 			if (err)
5643 				goto restore_opts;
5644 
5645 			sb->s_flags &= ~SB_RDONLY;
5646 			if (ext4_has_feature_mmp(sb))
5647 				if (ext4_multi_mount_protect(sb,
5648 						le64_to_cpu(es->s_mmp_block))) {
5649 					err = -EROFS;
5650 					goto restore_opts;
5651 				}
5652 			enable_quota = 1;
5653 		}
5654 	}
5655 
5656 	/*
5657 	 * Reinitialize lazy itable initialization thread based on
5658 	 * current settings
5659 	 */
5660 	if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5661 		ext4_unregister_li_request(sb);
5662 	else {
5663 		ext4_group_t first_not_zeroed;
5664 		first_not_zeroed = ext4_has_uninit_itable(sb);
5665 		ext4_register_li_request(sb, first_not_zeroed);
5666 	}
5667 
5668 	ext4_setup_system_zone(sb);
5669 	if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5670 		err = ext4_commit_super(sb, 1);
5671 		if (err)
5672 			goto restore_opts;
5673 	}
5674 
5675 #ifdef CONFIG_QUOTA
5676 	/* Release old quota file names */
5677 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5678 		kfree(old_opts.s_qf_names[i]);
5679 	if (enable_quota) {
5680 		if (sb_any_quota_suspended(sb))
5681 			dquot_resume(sb, -1);
5682 		else if (ext4_has_feature_quota(sb)) {
5683 			err = ext4_enable_quotas(sb);
5684 			if (err)
5685 				goto restore_opts;
5686 		}
5687 	}
5688 #endif
5689 
5690 	*flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5691 	ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5692 	kfree(orig_data);
5693 	return 0;
5694 
5695 restore_opts:
5696 	sb->s_flags = old_sb_flags;
5697 	sbi->s_mount_opt = old_opts.s_mount_opt;
5698 	sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5699 	sbi->s_resuid = old_opts.s_resuid;
5700 	sbi->s_resgid = old_opts.s_resgid;
5701 	sbi->s_commit_interval = old_opts.s_commit_interval;
5702 	sbi->s_min_batch_time = old_opts.s_min_batch_time;
5703 	sbi->s_max_batch_time = old_opts.s_max_batch_time;
5704 #ifdef CONFIG_QUOTA
5705 	sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5706 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5707 		to_free[i] = get_qf_name(sb, sbi, i);
5708 		rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5709 	}
5710 	synchronize_rcu();
5711 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5712 		kfree(to_free[i]);
5713 #endif
5714 	kfree(orig_data);
5715 	return err;
5716 }
5717 
5718 #ifdef CONFIG_QUOTA
5719 static int ext4_statfs_project(struct super_block *sb,
5720 			       kprojid_t projid, struct kstatfs *buf)
5721 {
5722 	struct kqid qid;
5723 	struct dquot *dquot;
5724 	u64 limit;
5725 	u64 curblock;
5726 
5727 	qid = make_kqid_projid(projid);
5728 	dquot = dqget(sb, qid);
5729 	if (IS_ERR(dquot))
5730 		return PTR_ERR(dquot);
5731 	spin_lock(&dquot->dq_dqb_lock);
5732 
5733 	limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
5734 			     dquot->dq_dqb.dqb_bhardlimit);
5735 	limit >>= sb->s_blocksize_bits;
5736 
5737 	if (limit && buf->f_blocks > limit) {
5738 		curblock = (dquot->dq_dqb.dqb_curspace +
5739 			    dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5740 		buf->f_blocks = limit;
5741 		buf->f_bfree = buf->f_bavail =
5742 			(buf->f_blocks > curblock) ?
5743 			 (buf->f_blocks - curblock) : 0;
5744 	}
5745 
5746 	limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
5747 			     dquot->dq_dqb.dqb_ihardlimit);
5748 	if (limit && buf->f_files > limit) {
5749 		buf->f_files = limit;
5750 		buf->f_ffree =
5751 			(buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5752 			 (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5753 	}
5754 
5755 	spin_unlock(&dquot->dq_dqb_lock);
5756 	dqput(dquot);
5757 	return 0;
5758 }
5759 #endif
5760 
5761 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5762 {
5763 	struct super_block *sb = dentry->d_sb;
5764 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5765 	struct ext4_super_block *es = sbi->s_es;
5766 	ext4_fsblk_t overhead = 0, resv_blocks;
5767 	u64 fsid;
5768 	s64 bfree;
5769 	resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5770 
5771 	if (!test_opt(sb, MINIX_DF))
5772 		overhead = sbi->s_overhead;
5773 
5774 	buf->f_type = EXT4_SUPER_MAGIC;
5775 	buf->f_bsize = sb->s_blocksize;
5776 	buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5777 	bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5778 		percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5779 	/* prevent underflow in case that few free space is available */
5780 	buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5781 	buf->f_bavail = buf->f_bfree -
5782 			(ext4_r_blocks_count(es) + resv_blocks);
5783 	if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5784 		buf->f_bavail = 0;
5785 	buf->f_files = le32_to_cpu(es->s_inodes_count);
5786 	buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5787 	buf->f_namelen = EXT4_NAME_LEN;
5788 	fsid = le64_to_cpup((void *)es->s_uuid) ^
5789 	       le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5790 	buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5791 	buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5792 
5793 #ifdef CONFIG_QUOTA
5794 	if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5795 	    sb_has_quota_limits_enabled(sb, PRJQUOTA))
5796 		ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5797 #endif
5798 	return 0;
5799 }
5800 
5801 
5802 #ifdef CONFIG_QUOTA
5803 
5804 /*
5805  * Helper functions so that transaction is started before we acquire dqio_sem
5806  * to keep correct lock ordering of transaction > dqio_sem
5807  */
5808 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5809 {
5810 	return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5811 }
5812 
5813 static int ext4_write_dquot(struct dquot *dquot)
5814 {
5815 	int ret, err;
5816 	handle_t *handle;
5817 	struct inode *inode;
5818 
5819 	inode = dquot_to_inode(dquot);
5820 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5821 				    EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5822 	if (IS_ERR(handle))
5823 		return PTR_ERR(handle);
5824 	ret = dquot_commit(dquot);
5825 	err = ext4_journal_stop(handle);
5826 	if (!ret)
5827 		ret = err;
5828 	return ret;
5829 }
5830 
5831 static int ext4_acquire_dquot(struct dquot *dquot)
5832 {
5833 	int ret, err;
5834 	handle_t *handle;
5835 
5836 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5837 				    EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5838 	if (IS_ERR(handle))
5839 		return PTR_ERR(handle);
5840 	ret = dquot_acquire(dquot);
5841 	err = ext4_journal_stop(handle);
5842 	if (!ret)
5843 		ret = err;
5844 	return ret;
5845 }
5846 
5847 static int ext4_release_dquot(struct dquot *dquot)
5848 {
5849 	int ret, err;
5850 	handle_t *handle;
5851 
5852 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5853 				    EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5854 	if (IS_ERR(handle)) {
5855 		/* Release dquot anyway to avoid endless cycle in dqput() */
5856 		dquot_release(dquot);
5857 		return PTR_ERR(handle);
5858 	}
5859 	ret = dquot_release(dquot);
5860 	err = ext4_journal_stop(handle);
5861 	if (!ret)
5862 		ret = err;
5863 	return ret;
5864 }
5865 
5866 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5867 {
5868 	struct super_block *sb = dquot->dq_sb;
5869 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5870 
5871 	/* Are we journaling quotas? */
5872 	if (ext4_has_feature_quota(sb) ||
5873 	    sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5874 		dquot_mark_dquot_dirty(dquot);
5875 		return ext4_write_dquot(dquot);
5876 	} else {
5877 		return dquot_mark_dquot_dirty(dquot);
5878 	}
5879 }
5880 
5881 static int ext4_write_info(struct super_block *sb, int type)
5882 {
5883 	int ret, err;
5884 	handle_t *handle;
5885 
5886 	/* Data block + inode block */
5887 	handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5888 	if (IS_ERR(handle))
5889 		return PTR_ERR(handle);
5890 	ret = dquot_commit_info(sb, type);
5891 	err = ext4_journal_stop(handle);
5892 	if (!ret)
5893 		ret = err;
5894 	return ret;
5895 }
5896 
5897 /*
5898  * Turn on quotas during mount time - we need to find
5899  * the quota file and such...
5900  */
5901 static int ext4_quota_on_mount(struct super_block *sb, int type)
5902 {
5903 	return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5904 					EXT4_SB(sb)->s_jquota_fmt, type);
5905 }
5906 
5907 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5908 {
5909 	struct ext4_inode_info *ei = EXT4_I(inode);
5910 
5911 	/* The first argument of lockdep_set_subclass has to be
5912 	 * *exactly* the same as the argument to init_rwsem() --- in
5913 	 * this case, in init_once() --- or lockdep gets unhappy
5914 	 * because the name of the lock is set using the
5915 	 * stringification of the argument to init_rwsem().
5916 	 */
5917 	(void) ei;	/* shut up clang warning if !CONFIG_LOCKDEP */
5918 	lockdep_set_subclass(&ei->i_data_sem, subclass);
5919 }
5920 
5921 /*
5922  * Standard function to be called on quota_on
5923  */
5924 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5925 			 const struct path *path)
5926 {
5927 	int err;
5928 
5929 	if (!test_opt(sb, QUOTA))
5930 		return -EINVAL;
5931 
5932 	/* Quotafile not on the same filesystem? */
5933 	if (path->dentry->d_sb != sb)
5934 		return -EXDEV;
5935 	/* Journaling quota? */
5936 	if (EXT4_SB(sb)->s_qf_names[type]) {
5937 		/* Quotafile not in fs root? */
5938 		if (path->dentry->d_parent != sb->s_root)
5939 			ext4_msg(sb, KERN_WARNING,
5940 				"Quota file not on filesystem root. "
5941 				"Journaled quota will not work");
5942 		sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5943 	} else {
5944 		/*
5945 		 * Clear the flag just in case mount options changed since
5946 		 * last time.
5947 		 */
5948 		sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5949 	}
5950 
5951 	/*
5952 	 * When we journal data on quota file, we have to flush journal to see
5953 	 * all updates to the file when we bypass pagecache...
5954 	 */
5955 	if (EXT4_SB(sb)->s_journal &&
5956 	    ext4_should_journal_data(d_inode(path->dentry))) {
5957 		/*
5958 		 * We don't need to lock updates but journal_flush() could
5959 		 * otherwise be livelocked...
5960 		 */
5961 		jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5962 		err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5963 		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5964 		if (err)
5965 			return err;
5966 	}
5967 
5968 	lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5969 	err = dquot_quota_on(sb, type, format_id, path);
5970 	if (err) {
5971 		lockdep_set_quota_inode(path->dentry->d_inode,
5972 					     I_DATA_SEM_NORMAL);
5973 	} else {
5974 		struct inode *inode = d_inode(path->dentry);
5975 		handle_t *handle;
5976 
5977 		/*
5978 		 * Set inode flags to prevent userspace from messing with quota
5979 		 * files. If this fails, we return success anyway since quotas
5980 		 * are already enabled and this is not a hard failure.
5981 		 */
5982 		inode_lock(inode);
5983 		handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5984 		if (IS_ERR(handle))
5985 			goto unlock_inode;
5986 		EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5987 		inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5988 				S_NOATIME | S_IMMUTABLE);
5989 		err = ext4_mark_inode_dirty(handle, inode);
5990 		ext4_journal_stop(handle);
5991 	unlock_inode:
5992 		inode_unlock(inode);
5993 	}
5994 	return err;
5995 }
5996 
5997 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5998 			     unsigned int flags)
5999 {
6000 	int err;
6001 	struct inode *qf_inode;
6002 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6003 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6004 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6005 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6006 	};
6007 
6008 	BUG_ON(!ext4_has_feature_quota(sb));
6009 
6010 	if (!qf_inums[type])
6011 		return -EPERM;
6012 
6013 	qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6014 	if (IS_ERR(qf_inode)) {
6015 		ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6016 		return PTR_ERR(qf_inode);
6017 	}
6018 
6019 	/* Don't account quota for quota files to avoid recursion */
6020 	qf_inode->i_flags |= S_NOQUOTA;
6021 	lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6022 	err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6023 	if (err)
6024 		lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6025 	iput(qf_inode);
6026 
6027 	return err;
6028 }
6029 
6030 /* Enable usage tracking for all quota types. */
6031 static int ext4_enable_quotas(struct super_block *sb)
6032 {
6033 	int type, err = 0;
6034 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6035 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6036 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6037 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6038 	};
6039 	bool quota_mopt[EXT4_MAXQUOTAS] = {
6040 		test_opt(sb, USRQUOTA),
6041 		test_opt(sb, GRPQUOTA),
6042 		test_opt(sb, PRJQUOTA),
6043 	};
6044 
6045 	sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6046 	for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6047 		if (qf_inums[type]) {
6048 			err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6049 				DQUOT_USAGE_ENABLED |
6050 				(quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6051 			if (err) {
6052 				ext4_warning(sb,
6053 					"Failed to enable quota tracking "
6054 					"(type=%d, err=%d). Please run "
6055 					"e2fsck to fix.", type, err);
6056 				for (type--; type >= 0; type--)
6057 					dquot_quota_off(sb, type);
6058 
6059 				return err;
6060 			}
6061 		}
6062 	}
6063 	return 0;
6064 }
6065 
6066 static int ext4_quota_off(struct super_block *sb, int type)
6067 {
6068 	struct inode *inode = sb_dqopt(sb)->files[type];
6069 	handle_t *handle;
6070 	int err;
6071 
6072 	/* Force all delayed allocation blocks to be allocated.
6073 	 * Caller already holds s_umount sem */
6074 	if (test_opt(sb, DELALLOC))
6075 		sync_filesystem(sb);
6076 
6077 	if (!inode || !igrab(inode))
6078 		goto out;
6079 
6080 	err = dquot_quota_off(sb, type);
6081 	if (err || ext4_has_feature_quota(sb))
6082 		goto out_put;
6083 
6084 	inode_lock(inode);
6085 	/*
6086 	 * Update modification times of quota files when userspace can
6087 	 * start looking at them. If we fail, we return success anyway since
6088 	 * this is not a hard failure and quotas are already disabled.
6089 	 */
6090 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6091 	if (IS_ERR(handle)) {
6092 		err = PTR_ERR(handle);
6093 		goto out_unlock;
6094 	}
6095 	EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6096 	inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6097 	inode->i_mtime = inode->i_ctime = current_time(inode);
6098 	err = ext4_mark_inode_dirty(handle, inode);
6099 	ext4_journal_stop(handle);
6100 out_unlock:
6101 	inode_unlock(inode);
6102 out_put:
6103 	lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6104 	iput(inode);
6105 	return err;
6106 out:
6107 	return dquot_quota_off(sb, type);
6108 }
6109 
6110 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6111  * acquiring the locks... As quota files are never truncated and quota code
6112  * itself serializes the operations (and no one else should touch the files)
6113  * we don't have to be afraid of races */
6114 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6115 			       size_t len, loff_t off)
6116 {
6117 	struct inode *inode = sb_dqopt(sb)->files[type];
6118 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6119 	int offset = off & (sb->s_blocksize - 1);
6120 	int tocopy;
6121 	size_t toread;
6122 	struct buffer_head *bh;
6123 	loff_t i_size = i_size_read(inode);
6124 
6125 	if (off > i_size)
6126 		return 0;
6127 	if (off+len > i_size)
6128 		len = i_size-off;
6129 	toread = len;
6130 	while (toread > 0) {
6131 		tocopy = sb->s_blocksize - offset < toread ?
6132 				sb->s_blocksize - offset : toread;
6133 		bh = ext4_bread(NULL, inode, blk, 0);
6134 		if (IS_ERR(bh))
6135 			return PTR_ERR(bh);
6136 		if (!bh)	/* A hole? */
6137 			memset(data, 0, tocopy);
6138 		else
6139 			memcpy(data, bh->b_data+offset, tocopy);
6140 		brelse(bh);
6141 		offset = 0;
6142 		toread -= tocopy;
6143 		data += tocopy;
6144 		blk++;
6145 	}
6146 	return len;
6147 }
6148 
6149 /* Write to quotafile (we know the transaction is already started and has
6150  * enough credits) */
6151 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6152 				const char *data, size_t len, loff_t off)
6153 {
6154 	struct inode *inode = sb_dqopt(sb)->files[type];
6155 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6156 	int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6157 	int retries = 0;
6158 	struct buffer_head *bh;
6159 	handle_t *handle = journal_current_handle();
6160 
6161 	if (EXT4_SB(sb)->s_journal && !handle) {
6162 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6163 			" cancelled because transaction is not started",
6164 			(unsigned long long)off, (unsigned long long)len);
6165 		return -EIO;
6166 	}
6167 	/*
6168 	 * Since we account only one data block in transaction credits,
6169 	 * then it is impossible to cross a block boundary.
6170 	 */
6171 	if (sb->s_blocksize - offset < len) {
6172 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6173 			" cancelled because not block aligned",
6174 			(unsigned long long)off, (unsigned long long)len);
6175 		return -EIO;
6176 	}
6177 
6178 	do {
6179 		bh = ext4_bread(handle, inode, blk,
6180 				EXT4_GET_BLOCKS_CREATE |
6181 				EXT4_GET_BLOCKS_METADATA_NOFAIL);
6182 	} while (PTR_ERR(bh) == -ENOSPC &&
6183 		 ext4_should_retry_alloc(inode->i_sb, &retries));
6184 	if (IS_ERR(bh))
6185 		return PTR_ERR(bh);
6186 	if (!bh)
6187 		goto out;
6188 	BUFFER_TRACE(bh, "get write access");
6189 	err = ext4_journal_get_write_access(handle, bh);
6190 	if (err) {
6191 		brelse(bh);
6192 		return err;
6193 	}
6194 	lock_buffer(bh);
6195 	memcpy(bh->b_data+offset, data, len);
6196 	flush_dcache_page(bh->b_page);
6197 	unlock_buffer(bh);
6198 	err = ext4_handle_dirty_metadata(handle, NULL, bh);
6199 	brelse(bh);
6200 out:
6201 	if (inode->i_size < off + len) {
6202 		i_size_write(inode, off + len);
6203 		EXT4_I(inode)->i_disksize = inode->i_size;
6204 		err2 = ext4_mark_inode_dirty(handle, inode);
6205 		if (unlikely(err2 && !err))
6206 			err = err2;
6207 	}
6208 	return err ? err : len;
6209 }
6210 #endif
6211 
6212 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6213 		       const char *dev_name, void *data)
6214 {
6215 	return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6216 }
6217 
6218 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6219 static inline void register_as_ext2(void)
6220 {
6221 	int err = register_filesystem(&ext2_fs_type);
6222 	if (err)
6223 		printk(KERN_WARNING
6224 		       "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6225 }
6226 
6227 static inline void unregister_as_ext2(void)
6228 {
6229 	unregister_filesystem(&ext2_fs_type);
6230 }
6231 
6232 static inline int ext2_feature_set_ok(struct super_block *sb)
6233 {
6234 	if (ext4_has_unknown_ext2_incompat_features(sb))
6235 		return 0;
6236 	if (sb_rdonly(sb))
6237 		return 1;
6238 	if (ext4_has_unknown_ext2_ro_compat_features(sb))
6239 		return 0;
6240 	return 1;
6241 }
6242 #else
6243 static inline void register_as_ext2(void) { }
6244 static inline void unregister_as_ext2(void) { }
6245 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6246 #endif
6247 
6248 static inline void register_as_ext3(void)
6249 {
6250 	int err = register_filesystem(&ext3_fs_type);
6251 	if (err)
6252 		printk(KERN_WARNING
6253 		       "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6254 }
6255 
6256 static inline void unregister_as_ext3(void)
6257 {
6258 	unregister_filesystem(&ext3_fs_type);
6259 }
6260 
6261 static inline int ext3_feature_set_ok(struct super_block *sb)
6262 {
6263 	if (ext4_has_unknown_ext3_incompat_features(sb))
6264 		return 0;
6265 	if (!ext4_has_feature_journal(sb))
6266 		return 0;
6267 	if (sb_rdonly(sb))
6268 		return 1;
6269 	if (ext4_has_unknown_ext3_ro_compat_features(sb))
6270 		return 0;
6271 	return 1;
6272 }
6273 
6274 static struct file_system_type ext4_fs_type = {
6275 	.owner		= THIS_MODULE,
6276 	.name		= "ext4",
6277 	.mount		= ext4_mount,
6278 	.kill_sb	= kill_block_super,
6279 	.fs_flags	= FS_REQUIRES_DEV,
6280 };
6281 MODULE_ALIAS_FS("ext4");
6282 
6283 /* Shared across all ext4 file systems */
6284 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6285 
6286 static int __init ext4_init_fs(void)
6287 {
6288 	int i, err;
6289 
6290 	ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6291 	ext4_li_info = NULL;
6292 	mutex_init(&ext4_li_mtx);
6293 
6294 	/* Build-time check for flags consistency */
6295 	ext4_check_flag_values();
6296 
6297 	for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6298 		init_waitqueue_head(&ext4__ioend_wq[i]);
6299 
6300 	err = ext4_init_es();
6301 	if (err)
6302 		return err;
6303 
6304 	err = ext4_init_pending();
6305 	if (err)
6306 		goto out7;
6307 
6308 	err = ext4_init_post_read_processing();
6309 	if (err)
6310 		goto out6;
6311 
6312 	err = ext4_init_pageio();
6313 	if (err)
6314 		goto out5;
6315 
6316 	err = ext4_init_system_zone();
6317 	if (err)
6318 		goto out4;
6319 
6320 	err = ext4_init_sysfs();
6321 	if (err)
6322 		goto out3;
6323 
6324 	err = ext4_init_mballoc();
6325 	if (err)
6326 		goto out2;
6327 	err = init_inodecache();
6328 	if (err)
6329 		goto out1;
6330 	register_as_ext3();
6331 	register_as_ext2();
6332 	err = register_filesystem(&ext4_fs_type);
6333 	if (err)
6334 		goto out;
6335 
6336 	return 0;
6337 out:
6338 	unregister_as_ext2();
6339 	unregister_as_ext3();
6340 	destroy_inodecache();
6341 out1:
6342 	ext4_exit_mballoc();
6343 out2:
6344 	ext4_exit_sysfs();
6345 out3:
6346 	ext4_exit_system_zone();
6347 out4:
6348 	ext4_exit_pageio();
6349 out5:
6350 	ext4_exit_post_read_processing();
6351 out6:
6352 	ext4_exit_pending();
6353 out7:
6354 	ext4_exit_es();
6355 
6356 	return err;
6357 }
6358 
6359 static void __exit ext4_exit_fs(void)
6360 {
6361 	ext4_destroy_lazyinit_thread();
6362 	unregister_as_ext2();
6363 	unregister_as_ext3();
6364 	unregister_filesystem(&ext4_fs_type);
6365 	destroy_inodecache();
6366 	ext4_exit_mballoc();
6367 	ext4_exit_sysfs();
6368 	ext4_exit_system_zone();
6369 	ext4_exit_pageio();
6370 	ext4_exit_post_read_processing();
6371 	ext4_exit_es();
6372 	ext4_exit_pending();
6373 }
6374 
6375 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6376 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6377 MODULE_LICENSE("GPL");
6378 MODULE_SOFTDEP("pre: crc32c");
6379 module_init(ext4_init_fs)
6380 module_exit(ext4_exit_fs)
6381