xref: /openbmc/linux/fs/ext4/super.c (revision 74be2d3b)
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 		if (EXT4_SB(sb)->s_journal &&
526 		  !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
527 			return;
528 		panic("EXT4-fs (device %s): panic forced after error\n",
529 			sb->s_id);
530 	}
531 }
532 
533 #define ext4_error_ratelimit(sb)					\
534 		___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),	\
535 			     "EXT4-fs error")
536 
537 void __ext4_error(struct super_block *sb, const char *function,
538 		  unsigned int line, int error, __u64 block,
539 		  const char *fmt, ...)
540 {
541 	struct va_format vaf;
542 	va_list args;
543 
544 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
545 		return;
546 
547 	trace_ext4_error(sb, function, line);
548 	if (ext4_error_ratelimit(sb)) {
549 		va_start(args, fmt);
550 		vaf.fmt = fmt;
551 		vaf.va = &args;
552 		printk(KERN_CRIT
553 		       "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
554 		       sb->s_id, function, line, current->comm, &vaf);
555 		va_end(args);
556 	}
557 	save_error_info(sb, error, 0, block, function, line);
558 	ext4_handle_error(sb);
559 }
560 
561 void __ext4_error_inode(struct inode *inode, const char *function,
562 			unsigned int line, ext4_fsblk_t block, int error,
563 			const char *fmt, ...)
564 {
565 	va_list args;
566 	struct va_format vaf;
567 
568 	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
569 		return;
570 
571 	trace_ext4_error(inode->i_sb, function, line);
572 	if (ext4_error_ratelimit(inode->i_sb)) {
573 		va_start(args, fmt);
574 		vaf.fmt = fmt;
575 		vaf.va = &args;
576 		if (block)
577 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
578 			       "inode #%lu: block %llu: comm %s: %pV\n",
579 			       inode->i_sb->s_id, function, line, inode->i_ino,
580 			       block, current->comm, &vaf);
581 		else
582 			printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
583 			       "inode #%lu: comm %s: %pV\n",
584 			       inode->i_sb->s_id, function, line, inode->i_ino,
585 			       current->comm, &vaf);
586 		va_end(args);
587 	}
588 	save_error_info(inode->i_sb, error, inode->i_ino, block,
589 			function, line);
590 	ext4_handle_error(inode->i_sb);
591 }
592 
593 void __ext4_error_file(struct file *file, const char *function,
594 		       unsigned int line, ext4_fsblk_t block,
595 		       const char *fmt, ...)
596 {
597 	va_list args;
598 	struct va_format vaf;
599 	struct inode *inode = file_inode(file);
600 	char pathname[80], *path;
601 
602 	if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
603 		return;
604 
605 	trace_ext4_error(inode->i_sb, function, line);
606 	if (ext4_error_ratelimit(inode->i_sb)) {
607 		path = file_path(file, pathname, sizeof(pathname));
608 		if (IS_ERR(path))
609 			path = "(unknown)";
610 		va_start(args, fmt);
611 		vaf.fmt = fmt;
612 		vaf.va = &args;
613 		if (block)
614 			printk(KERN_CRIT
615 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
616 			       "block %llu: comm %s: path %s: %pV\n",
617 			       inode->i_sb->s_id, function, line, inode->i_ino,
618 			       block, current->comm, path, &vaf);
619 		else
620 			printk(KERN_CRIT
621 			       "EXT4-fs error (device %s): %s:%d: inode #%lu: "
622 			       "comm %s: path %s: %pV\n",
623 			       inode->i_sb->s_id, function, line, inode->i_ino,
624 			       current->comm, path, &vaf);
625 		va_end(args);
626 	}
627 	save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
628 			function, line);
629 	ext4_handle_error(inode->i_sb);
630 }
631 
632 const char *ext4_decode_error(struct super_block *sb, int errno,
633 			      char nbuf[16])
634 {
635 	char *errstr = NULL;
636 
637 	switch (errno) {
638 	case -EFSCORRUPTED:
639 		errstr = "Corrupt filesystem";
640 		break;
641 	case -EFSBADCRC:
642 		errstr = "Filesystem failed CRC";
643 		break;
644 	case -EIO:
645 		errstr = "IO failure";
646 		break;
647 	case -ENOMEM:
648 		errstr = "Out of memory";
649 		break;
650 	case -EROFS:
651 		if (!sb || (EXT4_SB(sb)->s_journal &&
652 			    EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
653 			errstr = "Journal has aborted";
654 		else
655 			errstr = "Readonly filesystem";
656 		break;
657 	default:
658 		/* If the caller passed in an extra buffer for unknown
659 		 * errors, textualise them now.  Else we just return
660 		 * NULL. */
661 		if (nbuf) {
662 			/* Check for truncated error codes... */
663 			if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
664 				errstr = nbuf;
665 		}
666 		break;
667 	}
668 
669 	return errstr;
670 }
671 
672 /* __ext4_std_error decodes expected errors from journaling functions
673  * automatically and invokes the appropriate error response.  */
674 
675 void __ext4_std_error(struct super_block *sb, const char *function,
676 		      unsigned int line, int errno)
677 {
678 	char nbuf[16];
679 	const char *errstr;
680 
681 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
682 		return;
683 
684 	/* Special case: if the error is EROFS, and we're not already
685 	 * inside a transaction, then there's really no point in logging
686 	 * an error. */
687 	if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
688 		return;
689 
690 	if (ext4_error_ratelimit(sb)) {
691 		errstr = ext4_decode_error(sb, errno, nbuf);
692 		printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
693 		       sb->s_id, function, line, errstr);
694 	}
695 
696 	save_error_info(sb, -errno, 0, 0, function, line);
697 	ext4_handle_error(sb);
698 }
699 
700 /*
701  * ext4_abort is a much stronger failure handler than ext4_error.  The
702  * abort function may be used to deal with unrecoverable failures such
703  * as journal IO errors or ENOMEM at a critical moment in log management.
704  *
705  * We unconditionally force the filesystem into an ABORT|READONLY state,
706  * unless the error response on the fs has been set to panic in which
707  * case we take the easy way out and panic immediately.
708  */
709 
710 void __ext4_abort(struct super_block *sb, const char *function,
711 		  unsigned int line, int error, const char *fmt, ...)
712 {
713 	struct va_format vaf;
714 	va_list args;
715 
716 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
717 		return;
718 
719 	save_error_info(sb, error, 0, 0, function, line);
720 	va_start(args, fmt);
721 	vaf.fmt = fmt;
722 	vaf.va = &args;
723 	printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
724 	       sb->s_id, function, line, &vaf);
725 	va_end(args);
726 
727 	if (sb_rdonly(sb) == 0) {
728 		ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
729 		EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
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 		if (EXT4_SB(sb)->s_journal)
737 			jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
738 	}
739 	if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
740 		if (EXT4_SB(sb)->s_journal &&
741 		  !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
742 			return;
743 		panic("EXT4-fs panic from previous error\n");
744 	}
745 }
746 
747 void __ext4_msg(struct super_block *sb,
748 		const char *prefix, const char *fmt, ...)
749 {
750 	struct va_format vaf;
751 	va_list args;
752 
753 	if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
754 		return;
755 
756 	va_start(args, fmt);
757 	vaf.fmt = fmt;
758 	vaf.va = &args;
759 	printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
760 	va_end(args);
761 }
762 
763 #define ext4_warning_ratelimit(sb)					\
764 		___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),	\
765 			     "EXT4-fs warning")
766 
767 void __ext4_warning(struct super_block *sb, const char *function,
768 		    unsigned int line, const char *fmt, ...)
769 {
770 	struct va_format vaf;
771 	va_list args;
772 
773 	if (!ext4_warning_ratelimit(sb))
774 		return;
775 
776 	va_start(args, fmt);
777 	vaf.fmt = fmt;
778 	vaf.va = &args;
779 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
780 	       sb->s_id, function, line, &vaf);
781 	va_end(args);
782 }
783 
784 void __ext4_warning_inode(const struct inode *inode, const char *function,
785 			  unsigned int line, const char *fmt, ...)
786 {
787 	struct va_format vaf;
788 	va_list args;
789 
790 	if (!ext4_warning_ratelimit(inode->i_sb))
791 		return;
792 
793 	va_start(args, fmt);
794 	vaf.fmt = fmt;
795 	vaf.va = &args;
796 	printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
797 	       "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
798 	       function, line, inode->i_ino, current->comm, &vaf);
799 	va_end(args);
800 }
801 
802 void __ext4_grp_locked_error(const char *function, unsigned int line,
803 			     struct super_block *sb, ext4_group_t grp,
804 			     unsigned long ino, ext4_fsblk_t block,
805 			     const char *fmt, ...)
806 __releases(bitlock)
807 __acquires(bitlock)
808 {
809 	struct va_format vaf;
810 	va_list args;
811 
812 	if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
813 		return;
814 
815 	trace_ext4_error(sb, function, line);
816 	__save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
817 
818 	if (ext4_error_ratelimit(sb)) {
819 		va_start(args, fmt);
820 		vaf.fmt = fmt;
821 		vaf.va = &args;
822 		printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
823 		       sb->s_id, function, line, grp);
824 		if (ino)
825 			printk(KERN_CONT "inode %lu: ", ino);
826 		if (block)
827 			printk(KERN_CONT "block %llu:",
828 			       (unsigned long long) block);
829 		printk(KERN_CONT "%pV\n", &vaf);
830 		va_end(args);
831 	}
832 
833 	if (test_opt(sb, WARN_ON_ERROR))
834 		WARN_ON_ONCE(1);
835 
836 	if (test_opt(sb, ERRORS_CONT)) {
837 		ext4_commit_super(sb, 0);
838 		return;
839 	}
840 
841 	ext4_unlock_group(sb, grp);
842 	ext4_commit_super(sb, 1);
843 	ext4_handle_error(sb);
844 	/*
845 	 * We only get here in the ERRORS_RO case; relocking the group
846 	 * may be dangerous, but nothing bad will happen since the
847 	 * filesystem will have already been marked read/only and the
848 	 * journal has been aborted.  We return 1 as a hint to callers
849 	 * who might what to use the return value from
850 	 * ext4_grp_locked_error() to distinguish between the
851 	 * ERRORS_CONT and ERRORS_RO case, and perhaps return more
852 	 * aggressively from the ext4 function in question, with a
853 	 * more appropriate error code.
854 	 */
855 	ext4_lock_group(sb, grp);
856 	return;
857 }
858 
859 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
860 				     ext4_group_t group,
861 				     unsigned int flags)
862 {
863 	struct ext4_sb_info *sbi = EXT4_SB(sb);
864 	struct ext4_group_info *grp = ext4_get_group_info(sb, group);
865 	struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
866 	int ret;
867 
868 	if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
869 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
870 					    &grp->bb_state);
871 		if (!ret)
872 			percpu_counter_sub(&sbi->s_freeclusters_counter,
873 					   grp->bb_free);
874 	}
875 
876 	if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
877 		ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
878 					    &grp->bb_state);
879 		if (!ret && gdp) {
880 			int count;
881 
882 			count = ext4_free_inodes_count(sb, gdp);
883 			percpu_counter_sub(&sbi->s_freeinodes_counter,
884 					   count);
885 		}
886 	}
887 }
888 
889 void ext4_update_dynamic_rev(struct super_block *sb)
890 {
891 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
892 
893 	if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
894 		return;
895 
896 	ext4_warning(sb,
897 		     "updating to rev %d because of new feature flag, "
898 		     "running e2fsck is recommended",
899 		     EXT4_DYNAMIC_REV);
900 
901 	es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
902 	es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
903 	es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
904 	/* leave es->s_feature_*compat flags alone */
905 	/* es->s_uuid will be set by e2fsck if empty */
906 
907 	/*
908 	 * The rest of the superblock fields should be zero, and if not it
909 	 * means they are likely already in use, so leave them alone.  We
910 	 * can leave it up to e2fsck to clean up any inconsistencies there.
911 	 */
912 }
913 
914 /*
915  * Open the external journal device
916  */
917 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
918 {
919 	struct block_device *bdev;
920 
921 	bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
922 	if (IS_ERR(bdev))
923 		goto fail;
924 	return bdev;
925 
926 fail:
927 	ext4_msg(sb, KERN_ERR,
928 		 "failed to open journal device unknown-block(%u,%u) %ld",
929 		 MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
930 	return NULL;
931 }
932 
933 /*
934  * Release the journal device
935  */
936 static void ext4_blkdev_put(struct block_device *bdev)
937 {
938 	blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
939 }
940 
941 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
942 {
943 	struct block_device *bdev;
944 	bdev = sbi->journal_bdev;
945 	if (bdev) {
946 		ext4_blkdev_put(bdev);
947 		sbi->journal_bdev = NULL;
948 	}
949 }
950 
951 static inline struct inode *orphan_list_entry(struct list_head *l)
952 {
953 	return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
954 }
955 
956 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
957 {
958 	struct list_head *l;
959 
960 	ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
961 		 le32_to_cpu(sbi->s_es->s_last_orphan));
962 
963 	printk(KERN_ERR "sb_info orphan list:\n");
964 	list_for_each(l, &sbi->s_orphan) {
965 		struct inode *inode = orphan_list_entry(l);
966 		printk(KERN_ERR "  "
967 		       "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
968 		       inode->i_sb->s_id, inode->i_ino, inode,
969 		       inode->i_mode, inode->i_nlink,
970 		       NEXT_ORPHAN(inode));
971 	}
972 }
973 
974 #ifdef CONFIG_QUOTA
975 static int ext4_quota_off(struct super_block *sb, int type);
976 
977 static inline void ext4_quota_off_umount(struct super_block *sb)
978 {
979 	int type;
980 
981 	/* Use our quota_off function to clear inode flags etc. */
982 	for (type = 0; type < EXT4_MAXQUOTAS; type++)
983 		ext4_quota_off(sb, type);
984 }
985 
986 /*
987  * This is a helper function which is used in the mount/remount
988  * codepaths (which holds s_umount) to fetch the quota file name.
989  */
990 static inline char *get_qf_name(struct super_block *sb,
991 				struct ext4_sb_info *sbi,
992 				int type)
993 {
994 	return rcu_dereference_protected(sbi->s_qf_names[type],
995 					 lockdep_is_held(&sb->s_umount));
996 }
997 #else
998 static inline void ext4_quota_off_umount(struct super_block *sb)
999 {
1000 }
1001 #endif
1002 
1003 static void ext4_put_super(struct super_block *sb)
1004 {
1005 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1006 	struct ext4_super_block *es = sbi->s_es;
1007 	struct buffer_head **group_desc;
1008 	struct flex_groups **flex_groups;
1009 	int aborted = 0;
1010 	int i, err;
1011 
1012 	ext4_unregister_li_request(sb);
1013 	ext4_quota_off_umount(sb);
1014 
1015 	destroy_workqueue(sbi->rsv_conversion_wq);
1016 
1017 	/*
1018 	 * Unregister sysfs before destroying jbd2 journal.
1019 	 * Since we could still access attr_journal_task attribute via sysfs
1020 	 * path which could have sbi->s_journal->j_task as NULL
1021 	 */
1022 	ext4_unregister_sysfs(sb);
1023 
1024 	if (sbi->s_journal) {
1025 		aborted = is_journal_aborted(sbi->s_journal);
1026 		err = jbd2_journal_destroy(sbi->s_journal);
1027 		sbi->s_journal = NULL;
1028 		if ((err < 0) && !aborted) {
1029 			ext4_abort(sb, -err, "Couldn't clean up the journal");
1030 		}
1031 	}
1032 
1033 	ext4_es_unregister_shrinker(sbi);
1034 	del_timer_sync(&sbi->s_err_report);
1035 	ext4_release_system_zone(sb);
1036 	ext4_mb_release(sb);
1037 	ext4_ext_release(sb);
1038 
1039 	if (!sb_rdonly(sb) && !aborted) {
1040 		ext4_clear_feature_journal_needs_recovery(sb);
1041 		es->s_state = cpu_to_le16(sbi->s_mount_state);
1042 	}
1043 	if (!sb_rdonly(sb))
1044 		ext4_commit_super(sb, 1);
1045 
1046 	rcu_read_lock();
1047 	group_desc = rcu_dereference(sbi->s_group_desc);
1048 	for (i = 0; i < sbi->s_gdb_count; i++)
1049 		brelse(group_desc[i]);
1050 	kvfree(group_desc);
1051 	flex_groups = rcu_dereference(sbi->s_flex_groups);
1052 	if (flex_groups) {
1053 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1054 			kvfree(flex_groups[i]);
1055 		kvfree(flex_groups);
1056 	}
1057 	rcu_read_unlock();
1058 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
1059 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
1060 	percpu_counter_destroy(&sbi->s_dirs_counter);
1061 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1062 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
1063 #ifdef CONFIG_QUOTA
1064 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
1065 		kfree(get_qf_name(sb, sbi, i));
1066 #endif
1067 
1068 	/* Debugging code just in case the in-memory inode orphan list
1069 	 * isn't empty.  The on-disk one can be non-empty if we've
1070 	 * detected an error and taken the fs readonly, but the
1071 	 * in-memory list had better be clean by this point. */
1072 	if (!list_empty(&sbi->s_orphan))
1073 		dump_orphan_list(sb, sbi);
1074 	J_ASSERT(list_empty(&sbi->s_orphan));
1075 
1076 	sync_blockdev(sb->s_bdev);
1077 	invalidate_bdev(sb->s_bdev);
1078 	if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1079 		/*
1080 		 * Invalidate the journal device's buffers.  We don't want them
1081 		 * floating about in memory - the physical journal device may
1082 		 * hotswapped, and it breaks the `ro-after' testing code.
1083 		 */
1084 		sync_blockdev(sbi->journal_bdev);
1085 		invalidate_bdev(sbi->journal_bdev);
1086 		ext4_blkdev_remove(sbi);
1087 	}
1088 
1089 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1090 	sbi->s_ea_inode_cache = NULL;
1091 
1092 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1093 	sbi->s_ea_block_cache = NULL;
1094 
1095 	if (sbi->s_mmp_tsk)
1096 		kthread_stop(sbi->s_mmp_tsk);
1097 	brelse(sbi->s_sbh);
1098 	sb->s_fs_info = NULL;
1099 	/*
1100 	 * Now that we are completely done shutting down the
1101 	 * superblock, we need to actually destroy the kobject.
1102 	 */
1103 	kobject_put(&sbi->s_kobj);
1104 	wait_for_completion(&sbi->s_kobj_unregister);
1105 	if (sbi->s_chksum_driver)
1106 		crypto_free_shash(sbi->s_chksum_driver);
1107 	kfree(sbi->s_blockgroup_lock);
1108 	fs_put_dax(sbi->s_daxdev);
1109 	fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
1110 #ifdef CONFIG_UNICODE
1111 	utf8_unload(sbi->s_encoding);
1112 #endif
1113 	kfree(sbi);
1114 }
1115 
1116 static struct kmem_cache *ext4_inode_cachep;
1117 
1118 /*
1119  * Called inside transaction, so use GFP_NOFS
1120  */
1121 static struct inode *ext4_alloc_inode(struct super_block *sb)
1122 {
1123 	struct ext4_inode_info *ei;
1124 
1125 	ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1126 	if (!ei)
1127 		return NULL;
1128 
1129 	inode_set_iversion(&ei->vfs_inode, 1);
1130 	spin_lock_init(&ei->i_raw_lock);
1131 	INIT_LIST_HEAD(&ei->i_prealloc_list);
1132 	spin_lock_init(&ei->i_prealloc_lock);
1133 	ext4_es_init_tree(&ei->i_es_tree);
1134 	rwlock_init(&ei->i_es_lock);
1135 	INIT_LIST_HEAD(&ei->i_es_list);
1136 	ei->i_es_all_nr = 0;
1137 	ei->i_es_shk_nr = 0;
1138 	ei->i_es_shrink_lblk = 0;
1139 	ei->i_reserved_data_blocks = 0;
1140 	spin_lock_init(&(ei->i_block_reservation_lock));
1141 	ext4_init_pending_tree(&ei->i_pending_tree);
1142 #ifdef CONFIG_QUOTA
1143 	ei->i_reserved_quota = 0;
1144 	memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1145 #endif
1146 	ei->jinode = NULL;
1147 	INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1148 	spin_lock_init(&ei->i_completed_io_lock);
1149 	ei->i_sync_tid = 0;
1150 	ei->i_datasync_tid = 0;
1151 	atomic_set(&ei->i_unwritten, 0);
1152 	INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1153 	return &ei->vfs_inode;
1154 }
1155 
1156 static int ext4_drop_inode(struct inode *inode)
1157 {
1158 	int drop = generic_drop_inode(inode);
1159 
1160 	if (!drop)
1161 		drop = fscrypt_drop_inode(inode);
1162 
1163 	trace_ext4_drop_inode(inode, drop);
1164 	return drop;
1165 }
1166 
1167 static void ext4_free_in_core_inode(struct inode *inode)
1168 {
1169 	fscrypt_free_inode(inode);
1170 	kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1171 }
1172 
1173 static void ext4_destroy_inode(struct inode *inode)
1174 {
1175 	if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1176 		ext4_msg(inode->i_sb, KERN_ERR,
1177 			 "Inode %lu (%p): orphan list check failed!",
1178 			 inode->i_ino, EXT4_I(inode));
1179 		print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1180 				EXT4_I(inode), sizeof(struct ext4_inode_info),
1181 				true);
1182 		dump_stack();
1183 	}
1184 }
1185 
1186 static void init_once(void *foo)
1187 {
1188 	struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1189 
1190 	INIT_LIST_HEAD(&ei->i_orphan);
1191 	init_rwsem(&ei->xattr_sem);
1192 	init_rwsem(&ei->i_data_sem);
1193 	init_rwsem(&ei->i_mmap_sem);
1194 	inode_init_once(&ei->vfs_inode);
1195 }
1196 
1197 static int __init init_inodecache(void)
1198 {
1199 	ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1200 				sizeof(struct ext4_inode_info), 0,
1201 				(SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1202 					SLAB_ACCOUNT),
1203 				offsetof(struct ext4_inode_info, i_data),
1204 				sizeof_field(struct ext4_inode_info, i_data),
1205 				init_once);
1206 	if (ext4_inode_cachep == NULL)
1207 		return -ENOMEM;
1208 	return 0;
1209 }
1210 
1211 static void destroy_inodecache(void)
1212 {
1213 	/*
1214 	 * Make sure all delayed rcu free inodes are flushed before we
1215 	 * destroy cache.
1216 	 */
1217 	rcu_barrier();
1218 	kmem_cache_destroy(ext4_inode_cachep);
1219 }
1220 
1221 void ext4_clear_inode(struct inode *inode)
1222 {
1223 	invalidate_inode_buffers(inode);
1224 	clear_inode(inode);
1225 	ext4_discard_preallocations(inode);
1226 	ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1227 	dquot_drop(inode);
1228 	if (EXT4_I(inode)->jinode) {
1229 		jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1230 					       EXT4_I(inode)->jinode);
1231 		jbd2_free_inode(EXT4_I(inode)->jinode);
1232 		EXT4_I(inode)->jinode = NULL;
1233 	}
1234 	fscrypt_put_encryption_info(inode);
1235 	fsverity_cleanup_inode(inode);
1236 }
1237 
1238 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1239 					u64 ino, u32 generation)
1240 {
1241 	struct inode *inode;
1242 
1243 	/*
1244 	 * Currently we don't know the generation for parent directory, so
1245 	 * a generation of 0 means "accept any"
1246 	 */
1247 	inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1248 	if (IS_ERR(inode))
1249 		return ERR_CAST(inode);
1250 	if (generation && inode->i_generation != generation) {
1251 		iput(inode);
1252 		return ERR_PTR(-ESTALE);
1253 	}
1254 
1255 	return inode;
1256 }
1257 
1258 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1259 					int fh_len, int fh_type)
1260 {
1261 	return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1262 				    ext4_nfs_get_inode);
1263 }
1264 
1265 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1266 					int fh_len, int fh_type)
1267 {
1268 	return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1269 				    ext4_nfs_get_inode);
1270 }
1271 
1272 static int ext4_nfs_commit_metadata(struct inode *inode)
1273 {
1274 	struct writeback_control wbc = {
1275 		.sync_mode = WB_SYNC_ALL
1276 	};
1277 
1278 	trace_ext4_nfs_commit_metadata(inode);
1279 	return ext4_write_inode(inode, &wbc);
1280 }
1281 
1282 /*
1283  * Try to release metadata pages (indirect blocks, directories) which are
1284  * mapped via the block device.  Since these pages could have journal heads
1285  * which would prevent try_to_free_buffers() from freeing them, we must use
1286  * jbd2 layer's try_to_free_buffers() function to release them.
1287  */
1288 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1289 				 gfp_t wait)
1290 {
1291 	journal_t *journal = EXT4_SB(sb)->s_journal;
1292 
1293 	WARN_ON(PageChecked(page));
1294 	if (!page_has_buffers(page))
1295 		return 0;
1296 	if (journal)
1297 		return jbd2_journal_try_to_free_buffers(journal, page,
1298 						wait & ~__GFP_DIRECT_RECLAIM);
1299 	return try_to_free_buffers(page);
1300 }
1301 
1302 #ifdef CONFIG_FS_ENCRYPTION
1303 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1304 {
1305 	return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1306 				 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1307 }
1308 
1309 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1310 							void *fs_data)
1311 {
1312 	handle_t *handle = fs_data;
1313 	int res, res2, credits, retries = 0;
1314 
1315 	/*
1316 	 * Encrypting the root directory is not allowed because e2fsck expects
1317 	 * lost+found to exist and be unencrypted, and encrypting the root
1318 	 * directory would imply encrypting the lost+found directory as well as
1319 	 * the filename "lost+found" itself.
1320 	 */
1321 	if (inode->i_ino == EXT4_ROOT_INO)
1322 		return -EPERM;
1323 
1324 	if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1325 		return -EINVAL;
1326 
1327 	res = ext4_convert_inline_data(inode);
1328 	if (res)
1329 		return res;
1330 
1331 	/*
1332 	 * If a journal handle was specified, then the encryption context is
1333 	 * being set on a new inode via inheritance and is part of a larger
1334 	 * transaction to create the inode.  Otherwise the encryption context is
1335 	 * being set on an existing inode in its own transaction.  Only in the
1336 	 * latter case should the "retry on ENOSPC" logic be used.
1337 	 */
1338 
1339 	if (handle) {
1340 		res = ext4_xattr_set_handle(handle, inode,
1341 					    EXT4_XATTR_INDEX_ENCRYPTION,
1342 					    EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1343 					    ctx, len, 0);
1344 		if (!res) {
1345 			ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1346 			ext4_clear_inode_state(inode,
1347 					EXT4_STATE_MAY_INLINE_DATA);
1348 			/*
1349 			 * Update inode->i_flags - S_ENCRYPTED will be enabled,
1350 			 * S_DAX may be disabled
1351 			 */
1352 			ext4_set_inode_flags(inode);
1353 		}
1354 		return res;
1355 	}
1356 
1357 	res = dquot_initialize(inode);
1358 	if (res)
1359 		return res;
1360 retry:
1361 	res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1362 				     &credits);
1363 	if (res)
1364 		return res;
1365 
1366 	handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1367 	if (IS_ERR(handle))
1368 		return PTR_ERR(handle);
1369 
1370 	res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1371 				    EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1372 				    ctx, len, 0);
1373 	if (!res) {
1374 		ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1375 		/*
1376 		 * Update inode->i_flags - S_ENCRYPTED will be enabled,
1377 		 * S_DAX may be disabled
1378 		 */
1379 		ext4_set_inode_flags(inode);
1380 		res = ext4_mark_inode_dirty(handle, inode);
1381 		if (res)
1382 			EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1383 	}
1384 	res2 = ext4_journal_stop(handle);
1385 
1386 	if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1387 		goto retry;
1388 	if (!res)
1389 		res = res2;
1390 	return res;
1391 }
1392 
1393 static const union fscrypt_context *
1394 ext4_get_dummy_context(struct super_block *sb)
1395 {
1396 	return EXT4_SB(sb)->s_dummy_enc_ctx.ctx;
1397 }
1398 
1399 static bool ext4_has_stable_inodes(struct super_block *sb)
1400 {
1401 	return ext4_has_feature_stable_inodes(sb);
1402 }
1403 
1404 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1405 				       int *ino_bits_ret, int *lblk_bits_ret)
1406 {
1407 	*ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1408 	*lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1409 }
1410 
1411 static const struct fscrypt_operations ext4_cryptops = {
1412 	.key_prefix		= "ext4:",
1413 	.get_context		= ext4_get_context,
1414 	.set_context		= ext4_set_context,
1415 	.get_dummy_context	= ext4_get_dummy_context,
1416 	.empty_dir		= ext4_empty_dir,
1417 	.max_namelen		= EXT4_NAME_LEN,
1418 	.has_stable_inodes	= ext4_has_stable_inodes,
1419 	.get_ino_and_lblk_bits	= ext4_get_ino_and_lblk_bits,
1420 };
1421 #endif
1422 
1423 #ifdef CONFIG_QUOTA
1424 static const char * const quotatypes[] = INITQFNAMES;
1425 #define QTYPE2NAME(t) (quotatypes[t])
1426 
1427 static int ext4_write_dquot(struct dquot *dquot);
1428 static int ext4_acquire_dquot(struct dquot *dquot);
1429 static int ext4_release_dquot(struct dquot *dquot);
1430 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1431 static int ext4_write_info(struct super_block *sb, int type);
1432 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1433 			 const struct path *path);
1434 static int ext4_quota_on_mount(struct super_block *sb, int type);
1435 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1436 			       size_t len, loff_t off);
1437 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1438 				const char *data, size_t len, loff_t off);
1439 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1440 			     unsigned int flags);
1441 static int ext4_enable_quotas(struct super_block *sb);
1442 
1443 static struct dquot **ext4_get_dquots(struct inode *inode)
1444 {
1445 	return EXT4_I(inode)->i_dquot;
1446 }
1447 
1448 static const struct dquot_operations ext4_quota_operations = {
1449 	.get_reserved_space	= ext4_get_reserved_space,
1450 	.write_dquot		= ext4_write_dquot,
1451 	.acquire_dquot		= ext4_acquire_dquot,
1452 	.release_dquot		= ext4_release_dquot,
1453 	.mark_dirty		= ext4_mark_dquot_dirty,
1454 	.write_info		= ext4_write_info,
1455 	.alloc_dquot		= dquot_alloc,
1456 	.destroy_dquot		= dquot_destroy,
1457 	.get_projid		= ext4_get_projid,
1458 	.get_inode_usage	= ext4_get_inode_usage,
1459 	.get_next_id		= dquot_get_next_id,
1460 };
1461 
1462 static const struct quotactl_ops ext4_qctl_operations = {
1463 	.quota_on	= ext4_quota_on,
1464 	.quota_off	= ext4_quota_off,
1465 	.quota_sync	= dquot_quota_sync,
1466 	.get_state	= dquot_get_state,
1467 	.set_info	= dquot_set_dqinfo,
1468 	.get_dqblk	= dquot_get_dqblk,
1469 	.set_dqblk	= dquot_set_dqblk,
1470 	.get_nextdqblk	= dquot_get_next_dqblk,
1471 };
1472 #endif
1473 
1474 static const struct super_operations ext4_sops = {
1475 	.alloc_inode	= ext4_alloc_inode,
1476 	.free_inode	= ext4_free_in_core_inode,
1477 	.destroy_inode	= ext4_destroy_inode,
1478 	.write_inode	= ext4_write_inode,
1479 	.dirty_inode	= ext4_dirty_inode,
1480 	.drop_inode	= ext4_drop_inode,
1481 	.evict_inode	= ext4_evict_inode,
1482 	.put_super	= ext4_put_super,
1483 	.sync_fs	= ext4_sync_fs,
1484 	.freeze_fs	= ext4_freeze,
1485 	.unfreeze_fs	= ext4_unfreeze,
1486 	.statfs		= ext4_statfs,
1487 	.remount_fs	= ext4_remount,
1488 	.show_options	= ext4_show_options,
1489 #ifdef CONFIG_QUOTA
1490 	.quota_read	= ext4_quota_read,
1491 	.quota_write	= ext4_quota_write,
1492 	.get_dquots	= ext4_get_dquots,
1493 #endif
1494 	.bdev_try_to_free_page = bdev_try_to_free_page,
1495 };
1496 
1497 static const struct export_operations ext4_export_ops = {
1498 	.fh_to_dentry = ext4_fh_to_dentry,
1499 	.fh_to_parent = ext4_fh_to_parent,
1500 	.get_parent = ext4_get_parent,
1501 	.commit_metadata = ext4_nfs_commit_metadata,
1502 };
1503 
1504 enum {
1505 	Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1506 	Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1507 	Opt_nouid32, Opt_debug, Opt_removed,
1508 	Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1509 	Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1510 	Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1511 	Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1512 	Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1513 	Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1514 	Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1515 	Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1516 	Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1517 	Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1518 	Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1519 	Opt_nowarn_on_error, Opt_mblk_io_submit,
1520 	Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1521 	Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1522 	Opt_inode_readahead_blks, Opt_journal_ioprio,
1523 	Opt_dioread_nolock, Opt_dioread_lock,
1524 	Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1525 	Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1526 };
1527 
1528 static const match_table_t tokens = {
1529 	{Opt_bsd_df, "bsddf"},
1530 	{Opt_minix_df, "minixdf"},
1531 	{Opt_grpid, "grpid"},
1532 	{Opt_grpid, "bsdgroups"},
1533 	{Opt_nogrpid, "nogrpid"},
1534 	{Opt_nogrpid, "sysvgroups"},
1535 	{Opt_resgid, "resgid=%u"},
1536 	{Opt_resuid, "resuid=%u"},
1537 	{Opt_sb, "sb=%u"},
1538 	{Opt_err_cont, "errors=continue"},
1539 	{Opt_err_panic, "errors=panic"},
1540 	{Opt_err_ro, "errors=remount-ro"},
1541 	{Opt_nouid32, "nouid32"},
1542 	{Opt_debug, "debug"},
1543 	{Opt_removed, "oldalloc"},
1544 	{Opt_removed, "orlov"},
1545 	{Opt_user_xattr, "user_xattr"},
1546 	{Opt_nouser_xattr, "nouser_xattr"},
1547 	{Opt_acl, "acl"},
1548 	{Opt_noacl, "noacl"},
1549 	{Opt_noload, "norecovery"},
1550 	{Opt_noload, "noload"},
1551 	{Opt_removed, "nobh"},
1552 	{Opt_removed, "bh"},
1553 	{Opt_commit, "commit=%u"},
1554 	{Opt_min_batch_time, "min_batch_time=%u"},
1555 	{Opt_max_batch_time, "max_batch_time=%u"},
1556 	{Opt_journal_dev, "journal_dev=%u"},
1557 	{Opt_journal_path, "journal_path=%s"},
1558 	{Opt_journal_checksum, "journal_checksum"},
1559 	{Opt_nojournal_checksum, "nojournal_checksum"},
1560 	{Opt_journal_async_commit, "journal_async_commit"},
1561 	{Opt_abort, "abort"},
1562 	{Opt_data_journal, "data=journal"},
1563 	{Opt_data_ordered, "data=ordered"},
1564 	{Opt_data_writeback, "data=writeback"},
1565 	{Opt_data_err_abort, "data_err=abort"},
1566 	{Opt_data_err_ignore, "data_err=ignore"},
1567 	{Opt_offusrjquota, "usrjquota="},
1568 	{Opt_usrjquota, "usrjquota=%s"},
1569 	{Opt_offgrpjquota, "grpjquota="},
1570 	{Opt_grpjquota, "grpjquota=%s"},
1571 	{Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1572 	{Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1573 	{Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1574 	{Opt_grpquota, "grpquota"},
1575 	{Opt_noquota, "noquota"},
1576 	{Opt_quota, "quota"},
1577 	{Opt_usrquota, "usrquota"},
1578 	{Opt_prjquota, "prjquota"},
1579 	{Opt_barrier, "barrier=%u"},
1580 	{Opt_barrier, "barrier"},
1581 	{Opt_nobarrier, "nobarrier"},
1582 	{Opt_i_version, "i_version"},
1583 	{Opt_dax, "dax"},
1584 	{Opt_stripe, "stripe=%u"},
1585 	{Opt_delalloc, "delalloc"},
1586 	{Opt_warn_on_error, "warn_on_error"},
1587 	{Opt_nowarn_on_error, "nowarn_on_error"},
1588 	{Opt_lazytime, "lazytime"},
1589 	{Opt_nolazytime, "nolazytime"},
1590 	{Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1591 	{Opt_nodelalloc, "nodelalloc"},
1592 	{Opt_removed, "mblk_io_submit"},
1593 	{Opt_removed, "nomblk_io_submit"},
1594 	{Opt_block_validity, "block_validity"},
1595 	{Opt_noblock_validity, "noblock_validity"},
1596 	{Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1597 	{Opt_journal_ioprio, "journal_ioprio=%u"},
1598 	{Opt_auto_da_alloc, "auto_da_alloc=%u"},
1599 	{Opt_auto_da_alloc, "auto_da_alloc"},
1600 	{Opt_noauto_da_alloc, "noauto_da_alloc"},
1601 	{Opt_dioread_nolock, "dioread_nolock"},
1602 	{Opt_dioread_lock, "nodioread_nolock"},
1603 	{Opt_dioread_lock, "dioread_lock"},
1604 	{Opt_discard, "discard"},
1605 	{Opt_nodiscard, "nodiscard"},
1606 	{Opt_init_itable, "init_itable=%u"},
1607 	{Opt_init_itable, "init_itable"},
1608 	{Opt_noinit_itable, "noinit_itable"},
1609 	{Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1610 	{Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1611 	{Opt_test_dummy_encryption, "test_dummy_encryption"},
1612 	{Opt_nombcache, "nombcache"},
1613 	{Opt_nombcache, "no_mbcache"},	/* for backward compatibility */
1614 	{Opt_removed, "check=none"},	/* mount option from ext2/3 */
1615 	{Opt_removed, "nocheck"},	/* mount option from ext2/3 */
1616 	{Opt_removed, "reservation"},	/* mount option from ext2/3 */
1617 	{Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1618 	{Opt_removed, "journal=%u"},	/* mount option from ext2/3 */
1619 	{Opt_err, NULL},
1620 };
1621 
1622 static ext4_fsblk_t get_sb_block(void **data)
1623 {
1624 	ext4_fsblk_t	sb_block;
1625 	char		*options = (char *) *data;
1626 
1627 	if (!options || strncmp(options, "sb=", 3) != 0)
1628 		return 1;	/* Default location */
1629 
1630 	options += 3;
1631 	/* TODO: use simple_strtoll with >32bit ext4 */
1632 	sb_block = simple_strtoul(options, &options, 0);
1633 	if (*options && *options != ',') {
1634 		printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1635 		       (char *) *data);
1636 		return 1;
1637 	}
1638 	if (*options == ',')
1639 		options++;
1640 	*data = (void *) options;
1641 
1642 	return sb_block;
1643 }
1644 
1645 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1646 static const char deprecated_msg[] =
1647 	"Mount option \"%s\" will be removed by %s\n"
1648 	"Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1649 
1650 #ifdef CONFIG_QUOTA
1651 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1652 {
1653 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1654 	char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1655 	int ret = -1;
1656 
1657 	if (sb_any_quota_loaded(sb) && !old_qname) {
1658 		ext4_msg(sb, KERN_ERR,
1659 			"Cannot change journaled "
1660 			"quota options when quota turned on");
1661 		return -1;
1662 	}
1663 	if (ext4_has_feature_quota(sb)) {
1664 		ext4_msg(sb, KERN_INFO, "Journaled quota options "
1665 			 "ignored when QUOTA feature is enabled");
1666 		return 1;
1667 	}
1668 	qname = match_strdup(args);
1669 	if (!qname) {
1670 		ext4_msg(sb, KERN_ERR,
1671 			"Not enough memory for storing quotafile name");
1672 		return -1;
1673 	}
1674 	if (old_qname) {
1675 		if (strcmp(old_qname, qname) == 0)
1676 			ret = 1;
1677 		else
1678 			ext4_msg(sb, KERN_ERR,
1679 				 "%s quota file already specified",
1680 				 QTYPE2NAME(qtype));
1681 		goto errout;
1682 	}
1683 	if (strchr(qname, '/')) {
1684 		ext4_msg(sb, KERN_ERR,
1685 			"quotafile must be on filesystem root");
1686 		goto errout;
1687 	}
1688 	rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1689 	set_opt(sb, QUOTA);
1690 	return 1;
1691 errout:
1692 	kfree(qname);
1693 	return ret;
1694 }
1695 
1696 static int clear_qf_name(struct super_block *sb, int qtype)
1697 {
1698 
1699 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1700 	char *old_qname = get_qf_name(sb, sbi, qtype);
1701 
1702 	if (sb_any_quota_loaded(sb) && old_qname) {
1703 		ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1704 			" when quota turned on");
1705 		return -1;
1706 	}
1707 	rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1708 	synchronize_rcu();
1709 	kfree(old_qname);
1710 	return 1;
1711 }
1712 #endif
1713 
1714 #define MOPT_SET	0x0001
1715 #define MOPT_CLEAR	0x0002
1716 #define MOPT_NOSUPPORT	0x0004
1717 #define MOPT_EXPLICIT	0x0008
1718 #define MOPT_CLEAR_ERR	0x0010
1719 #define MOPT_GTE0	0x0020
1720 #ifdef CONFIG_QUOTA
1721 #define MOPT_Q		0
1722 #define MOPT_QFMT	0x0040
1723 #else
1724 #define MOPT_Q		MOPT_NOSUPPORT
1725 #define MOPT_QFMT	MOPT_NOSUPPORT
1726 #endif
1727 #define MOPT_DATAJ	0x0080
1728 #define MOPT_NO_EXT2	0x0100
1729 #define MOPT_NO_EXT3	0x0200
1730 #define MOPT_EXT4_ONLY	(MOPT_NO_EXT2 | MOPT_NO_EXT3)
1731 #define MOPT_STRING	0x0400
1732 
1733 static const struct mount_opts {
1734 	int	token;
1735 	int	mount_opt;
1736 	int	flags;
1737 } ext4_mount_opts[] = {
1738 	{Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1739 	{Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1740 	{Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1741 	{Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1742 	{Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1743 	{Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1744 	{Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1745 	 MOPT_EXT4_ONLY | MOPT_SET},
1746 	{Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1747 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1748 	{Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1749 	{Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1750 	{Opt_delalloc, EXT4_MOUNT_DELALLOC,
1751 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1752 	{Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1753 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1754 	{Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1755 	{Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1756 	{Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1757 	 MOPT_EXT4_ONLY | MOPT_CLEAR},
1758 	{Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1759 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1760 	{Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1761 				    EXT4_MOUNT_JOURNAL_CHECKSUM),
1762 	 MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1763 	{Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1764 	{Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1765 	{Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1766 	{Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1767 	{Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1768 	 MOPT_NO_EXT2},
1769 	{Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1770 	 MOPT_NO_EXT2},
1771 	{Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1772 	{Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1773 	{Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1774 	{Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1775 	{Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1776 	{Opt_commit, 0, MOPT_GTE0},
1777 	{Opt_max_batch_time, 0, MOPT_GTE0},
1778 	{Opt_min_batch_time, 0, MOPT_GTE0},
1779 	{Opt_inode_readahead_blks, 0, MOPT_GTE0},
1780 	{Opt_init_itable, 0, MOPT_GTE0},
1781 	{Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1782 	{Opt_stripe, 0, MOPT_GTE0},
1783 	{Opt_resuid, 0, MOPT_GTE0},
1784 	{Opt_resgid, 0, MOPT_GTE0},
1785 	{Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1786 	{Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1787 	{Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1788 	{Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1789 	{Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1790 	{Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1791 	 MOPT_NO_EXT2 | MOPT_DATAJ},
1792 	{Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1793 	{Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1794 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1795 	{Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1796 	{Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1797 #else
1798 	{Opt_acl, 0, MOPT_NOSUPPORT},
1799 	{Opt_noacl, 0, MOPT_NOSUPPORT},
1800 #endif
1801 	{Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1802 	{Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1803 	{Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1804 	{Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1805 	{Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1806 							MOPT_SET | MOPT_Q},
1807 	{Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1808 							MOPT_SET | MOPT_Q},
1809 	{Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1810 							MOPT_SET | MOPT_Q},
1811 	{Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1812 		       EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1813 							MOPT_CLEAR | MOPT_Q},
1814 	{Opt_usrjquota, 0, MOPT_Q},
1815 	{Opt_grpjquota, 0, MOPT_Q},
1816 	{Opt_offusrjquota, 0, MOPT_Q},
1817 	{Opt_offgrpjquota, 0, MOPT_Q},
1818 	{Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1819 	{Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1820 	{Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1821 	{Opt_max_dir_size_kb, 0, MOPT_GTE0},
1822 	{Opt_test_dummy_encryption, 0, MOPT_STRING},
1823 	{Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1824 	{Opt_err, 0, 0}
1825 };
1826 
1827 #ifdef CONFIG_UNICODE
1828 static const struct ext4_sb_encodings {
1829 	__u16 magic;
1830 	char *name;
1831 	char *version;
1832 } ext4_sb_encoding_map[] = {
1833 	{EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1834 };
1835 
1836 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1837 				 const struct ext4_sb_encodings **encoding,
1838 				 __u16 *flags)
1839 {
1840 	__u16 magic = le16_to_cpu(es->s_encoding);
1841 	int i;
1842 
1843 	for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1844 		if (magic == ext4_sb_encoding_map[i].magic)
1845 			break;
1846 
1847 	if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1848 		return -EINVAL;
1849 
1850 	*encoding = &ext4_sb_encoding_map[i];
1851 	*flags = le16_to_cpu(es->s_encoding_flags);
1852 
1853 	return 0;
1854 }
1855 #endif
1856 
1857 static int ext4_set_test_dummy_encryption(struct super_block *sb,
1858 					  const char *opt,
1859 					  const substring_t *arg,
1860 					  bool is_remount)
1861 {
1862 #ifdef CONFIG_FS_ENCRYPTION
1863 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1864 	int err;
1865 
1866 	/*
1867 	 * This mount option is just for testing, and it's not worthwhile to
1868 	 * implement the extra complexity (e.g. RCU protection) that would be
1869 	 * needed to allow it to be set or changed during remount.  We do allow
1870 	 * it to be specified during remount, but only if there is no change.
1871 	 */
1872 	if (is_remount && !sbi->s_dummy_enc_ctx.ctx) {
1873 		ext4_msg(sb, KERN_WARNING,
1874 			 "Can't set test_dummy_encryption on remount");
1875 		return -1;
1876 	}
1877 	err = fscrypt_set_test_dummy_encryption(sb, arg, &sbi->s_dummy_enc_ctx);
1878 	if (err) {
1879 		if (err == -EEXIST)
1880 			ext4_msg(sb, KERN_WARNING,
1881 				 "Can't change test_dummy_encryption on remount");
1882 		else if (err == -EINVAL)
1883 			ext4_msg(sb, KERN_WARNING,
1884 				 "Value of option \"%s\" is unrecognized", opt);
1885 		else
1886 			ext4_msg(sb, KERN_WARNING,
1887 				 "Error processing option \"%s\" [%d]",
1888 				 opt, err);
1889 		return -1;
1890 	}
1891 	ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
1892 #else
1893 	ext4_msg(sb, KERN_WARNING,
1894 		 "Test dummy encryption mount option ignored");
1895 #endif
1896 	return 1;
1897 }
1898 
1899 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1900 			    substring_t *args, unsigned long *journal_devnum,
1901 			    unsigned int *journal_ioprio, int is_remount)
1902 {
1903 	struct ext4_sb_info *sbi = EXT4_SB(sb);
1904 	const struct mount_opts *m;
1905 	kuid_t uid;
1906 	kgid_t gid;
1907 	int arg = 0;
1908 
1909 #ifdef CONFIG_QUOTA
1910 	if (token == Opt_usrjquota)
1911 		return set_qf_name(sb, USRQUOTA, &args[0]);
1912 	else if (token == Opt_grpjquota)
1913 		return set_qf_name(sb, GRPQUOTA, &args[0]);
1914 	else if (token == Opt_offusrjquota)
1915 		return clear_qf_name(sb, USRQUOTA);
1916 	else if (token == Opt_offgrpjquota)
1917 		return clear_qf_name(sb, GRPQUOTA);
1918 #endif
1919 	switch (token) {
1920 	case Opt_noacl:
1921 	case Opt_nouser_xattr:
1922 		ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1923 		break;
1924 	case Opt_sb:
1925 		return 1;	/* handled by get_sb_block() */
1926 	case Opt_removed:
1927 		ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1928 		return 1;
1929 	case Opt_abort:
1930 		sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1931 		return 1;
1932 	case Opt_i_version:
1933 		sb->s_flags |= SB_I_VERSION;
1934 		return 1;
1935 	case Opt_lazytime:
1936 		sb->s_flags |= SB_LAZYTIME;
1937 		return 1;
1938 	case Opt_nolazytime:
1939 		sb->s_flags &= ~SB_LAZYTIME;
1940 		return 1;
1941 	}
1942 
1943 	for (m = ext4_mount_opts; m->token != Opt_err; m++)
1944 		if (token == m->token)
1945 			break;
1946 
1947 	if (m->token == Opt_err) {
1948 		ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1949 			 "or missing value", opt);
1950 		return -1;
1951 	}
1952 
1953 	if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1954 		ext4_msg(sb, KERN_ERR,
1955 			 "Mount option \"%s\" incompatible with ext2", opt);
1956 		return -1;
1957 	}
1958 	if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1959 		ext4_msg(sb, KERN_ERR,
1960 			 "Mount option \"%s\" incompatible with ext3", opt);
1961 		return -1;
1962 	}
1963 
1964 	if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1965 		return -1;
1966 	if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1967 		return -1;
1968 	if (m->flags & MOPT_EXPLICIT) {
1969 		if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1970 			set_opt2(sb, EXPLICIT_DELALLOC);
1971 		} else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1972 			set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1973 		} else
1974 			return -1;
1975 	}
1976 	if (m->flags & MOPT_CLEAR_ERR)
1977 		clear_opt(sb, ERRORS_MASK);
1978 	if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1979 		ext4_msg(sb, KERN_ERR, "Cannot change quota "
1980 			 "options when quota turned on");
1981 		return -1;
1982 	}
1983 
1984 	if (m->flags & MOPT_NOSUPPORT) {
1985 		ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1986 	} else if (token == Opt_commit) {
1987 		if (arg == 0)
1988 			arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1989 		else if (arg > INT_MAX / HZ) {
1990 			ext4_msg(sb, KERN_ERR,
1991 				 "Invalid commit interval %d, "
1992 				 "must be smaller than %d",
1993 				 arg, INT_MAX / HZ);
1994 			return -1;
1995 		}
1996 		sbi->s_commit_interval = HZ * arg;
1997 	} else if (token == Opt_debug_want_extra_isize) {
1998 		if ((arg & 1) ||
1999 		    (arg < 4) ||
2000 		    (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2001 			ext4_msg(sb, KERN_ERR,
2002 				 "Invalid want_extra_isize %d", arg);
2003 			return -1;
2004 		}
2005 		sbi->s_want_extra_isize = arg;
2006 	} else if (token == Opt_max_batch_time) {
2007 		sbi->s_max_batch_time = arg;
2008 	} else if (token == Opt_min_batch_time) {
2009 		sbi->s_min_batch_time = arg;
2010 	} else if (token == Opt_inode_readahead_blks) {
2011 		if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2012 			ext4_msg(sb, KERN_ERR,
2013 				 "EXT4-fs: inode_readahead_blks must be "
2014 				 "0 or a power of 2 smaller than 2^31");
2015 			return -1;
2016 		}
2017 		sbi->s_inode_readahead_blks = arg;
2018 	} else if (token == Opt_init_itable) {
2019 		set_opt(sb, INIT_INODE_TABLE);
2020 		if (!args->from)
2021 			arg = EXT4_DEF_LI_WAIT_MULT;
2022 		sbi->s_li_wait_mult = arg;
2023 	} else if (token == Opt_max_dir_size_kb) {
2024 		sbi->s_max_dir_size_kb = arg;
2025 	} else if (token == Opt_stripe) {
2026 		sbi->s_stripe = arg;
2027 	} else if (token == Opt_resuid) {
2028 		uid = make_kuid(current_user_ns(), arg);
2029 		if (!uid_valid(uid)) {
2030 			ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2031 			return -1;
2032 		}
2033 		sbi->s_resuid = uid;
2034 	} else if (token == Opt_resgid) {
2035 		gid = make_kgid(current_user_ns(), arg);
2036 		if (!gid_valid(gid)) {
2037 			ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2038 			return -1;
2039 		}
2040 		sbi->s_resgid = gid;
2041 	} else if (token == Opt_journal_dev) {
2042 		if (is_remount) {
2043 			ext4_msg(sb, KERN_ERR,
2044 				 "Cannot specify journal on remount");
2045 			return -1;
2046 		}
2047 		*journal_devnum = arg;
2048 	} else if (token == Opt_journal_path) {
2049 		char *journal_path;
2050 		struct inode *journal_inode;
2051 		struct path path;
2052 		int error;
2053 
2054 		if (is_remount) {
2055 			ext4_msg(sb, KERN_ERR,
2056 				 "Cannot specify journal on remount");
2057 			return -1;
2058 		}
2059 		journal_path = match_strdup(&args[0]);
2060 		if (!journal_path) {
2061 			ext4_msg(sb, KERN_ERR, "error: could not dup "
2062 				"journal device string");
2063 			return -1;
2064 		}
2065 
2066 		error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2067 		if (error) {
2068 			ext4_msg(sb, KERN_ERR, "error: could not find "
2069 				"journal device path: error %d", error);
2070 			kfree(journal_path);
2071 			return -1;
2072 		}
2073 
2074 		journal_inode = d_inode(path.dentry);
2075 		if (!S_ISBLK(journal_inode->i_mode)) {
2076 			ext4_msg(sb, KERN_ERR, "error: journal path %s "
2077 				"is not a block device", journal_path);
2078 			path_put(&path);
2079 			kfree(journal_path);
2080 			return -1;
2081 		}
2082 
2083 		*journal_devnum = new_encode_dev(journal_inode->i_rdev);
2084 		path_put(&path);
2085 		kfree(journal_path);
2086 	} else if (token == Opt_journal_ioprio) {
2087 		if (arg > 7) {
2088 			ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2089 				 " (must be 0-7)");
2090 			return -1;
2091 		}
2092 		*journal_ioprio =
2093 			IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2094 	} else if (token == Opt_test_dummy_encryption) {
2095 		return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2096 						      is_remount);
2097 	} else if (m->flags & MOPT_DATAJ) {
2098 		if (is_remount) {
2099 			if (!sbi->s_journal)
2100 				ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2101 			else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2102 				ext4_msg(sb, KERN_ERR,
2103 					 "Cannot change data mode on remount");
2104 				return -1;
2105 			}
2106 		} else {
2107 			clear_opt(sb, DATA_FLAGS);
2108 			sbi->s_mount_opt |= m->mount_opt;
2109 		}
2110 #ifdef CONFIG_QUOTA
2111 	} else if (m->flags & MOPT_QFMT) {
2112 		if (sb_any_quota_loaded(sb) &&
2113 		    sbi->s_jquota_fmt != m->mount_opt) {
2114 			ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2115 				 "quota options when quota turned on");
2116 			return -1;
2117 		}
2118 		if (ext4_has_feature_quota(sb)) {
2119 			ext4_msg(sb, KERN_INFO,
2120 				 "Quota format mount options ignored "
2121 				 "when QUOTA feature is enabled");
2122 			return 1;
2123 		}
2124 		sbi->s_jquota_fmt = m->mount_opt;
2125 #endif
2126 	} else if (token == Opt_dax) {
2127 #ifdef CONFIG_FS_DAX
2128 		ext4_msg(sb, KERN_WARNING,
2129 		"DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2130 		sbi->s_mount_opt |= m->mount_opt;
2131 #else
2132 		ext4_msg(sb, KERN_INFO, "dax option not supported");
2133 		return -1;
2134 #endif
2135 	} else if (token == Opt_data_err_abort) {
2136 		sbi->s_mount_opt |= m->mount_opt;
2137 	} else if (token == Opt_data_err_ignore) {
2138 		sbi->s_mount_opt &= ~m->mount_opt;
2139 	} else {
2140 		if (!args->from)
2141 			arg = 1;
2142 		if (m->flags & MOPT_CLEAR)
2143 			arg = !arg;
2144 		else if (unlikely(!(m->flags & MOPT_SET))) {
2145 			ext4_msg(sb, KERN_WARNING,
2146 				 "buggy handling of option %s", opt);
2147 			WARN_ON(1);
2148 			return -1;
2149 		}
2150 		if (arg != 0)
2151 			sbi->s_mount_opt |= m->mount_opt;
2152 		else
2153 			sbi->s_mount_opt &= ~m->mount_opt;
2154 	}
2155 	return 1;
2156 }
2157 
2158 static int parse_options(char *options, struct super_block *sb,
2159 			 unsigned long *journal_devnum,
2160 			 unsigned int *journal_ioprio,
2161 			 int is_remount)
2162 {
2163 	struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2164 	char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2165 	substring_t args[MAX_OPT_ARGS];
2166 	int token;
2167 
2168 	if (!options)
2169 		return 1;
2170 
2171 	while ((p = strsep(&options, ",")) != NULL) {
2172 		if (!*p)
2173 			continue;
2174 		/*
2175 		 * Initialize args struct so we know whether arg was
2176 		 * found; some options take optional arguments.
2177 		 */
2178 		args[0].to = args[0].from = NULL;
2179 		token = match_token(p, tokens, args);
2180 		if (handle_mount_opt(sb, p, token, args, journal_devnum,
2181 				     journal_ioprio, is_remount) < 0)
2182 			return 0;
2183 	}
2184 #ifdef CONFIG_QUOTA
2185 	/*
2186 	 * We do the test below only for project quotas. 'usrquota' and
2187 	 * 'grpquota' mount options are allowed even without quota feature
2188 	 * to support legacy quotas in quota files.
2189 	 */
2190 	if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2191 		ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2192 			 "Cannot enable project quota enforcement.");
2193 		return 0;
2194 	}
2195 	usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2196 	grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2197 	if (usr_qf_name || grp_qf_name) {
2198 		if (test_opt(sb, USRQUOTA) && usr_qf_name)
2199 			clear_opt(sb, USRQUOTA);
2200 
2201 		if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2202 			clear_opt(sb, GRPQUOTA);
2203 
2204 		if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2205 			ext4_msg(sb, KERN_ERR, "old and new quota "
2206 					"format mixing");
2207 			return 0;
2208 		}
2209 
2210 		if (!sbi->s_jquota_fmt) {
2211 			ext4_msg(sb, KERN_ERR, "journaled quota format "
2212 					"not specified");
2213 			return 0;
2214 		}
2215 	}
2216 #endif
2217 	if (test_opt(sb, DIOREAD_NOLOCK)) {
2218 		int blocksize =
2219 			BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2220 		if (blocksize < PAGE_SIZE)
2221 			ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2222 				 "experimental mount option 'dioread_nolock' "
2223 				 "for blocksize < PAGE_SIZE");
2224 	}
2225 	return 1;
2226 }
2227 
2228 static inline void ext4_show_quota_options(struct seq_file *seq,
2229 					   struct super_block *sb)
2230 {
2231 #if defined(CONFIG_QUOTA)
2232 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2233 	char *usr_qf_name, *grp_qf_name;
2234 
2235 	if (sbi->s_jquota_fmt) {
2236 		char *fmtname = "";
2237 
2238 		switch (sbi->s_jquota_fmt) {
2239 		case QFMT_VFS_OLD:
2240 			fmtname = "vfsold";
2241 			break;
2242 		case QFMT_VFS_V0:
2243 			fmtname = "vfsv0";
2244 			break;
2245 		case QFMT_VFS_V1:
2246 			fmtname = "vfsv1";
2247 			break;
2248 		}
2249 		seq_printf(seq, ",jqfmt=%s", fmtname);
2250 	}
2251 
2252 	rcu_read_lock();
2253 	usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2254 	grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2255 	if (usr_qf_name)
2256 		seq_show_option(seq, "usrjquota", usr_qf_name);
2257 	if (grp_qf_name)
2258 		seq_show_option(seq, "grpjquota", grp_qf_name);
2259 	rcu_read_unlock();
2260 #endif
2261 }
2262 
2263 static const char *token2str(int token)
2264 {
2265 	const struct match_token *t;
2266 
2267 	for (t = tokens; t->token != Opt_err; t++)
2268 		if (t->token == token && !strchr(t->pattern, '='))
2269 			break;
2270 	return t->pattern;
2271 }
2272 
2273 /*
2274  * Show an option if
2275  *  - it's set to a non-default value OR
2276  *  - if the per-sb default is different from the global default
2277  */
2278 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2279 			      int nodefs)
2280 {
2281 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2282 	struct ext4_super_block *es = sbi->s_es;
2283 	int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2284 	const struct mount_opts *m;
2285 	char sep = nodefs ? '\n' : ',';
2286 
2287 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2288 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2289 
2290 	if (sbi->s_sb_block != 1)
2291 		SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2292 
2293 	for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2294 		int want_set = m->flags & MOPT_SET;
2295 		if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2296 		    (m->flags & MOPT_CLEAR_ERR))
2297 			continue;
2298 		if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2299 			continue; /* skip if same as the default */
2300 		if ((want_set &&
2301 		     (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2302 		    (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2303 			continue; /* select Opt_noFoo vs Opt_Foo */
2304 		SEQ_OPTS_PRINT("%s", token2str(m->token));
2305 	}
2306 
2307 	if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2308 	    le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2309 		SEQ_OPTS_PRINT("resuid=%u",
2310 				from_kuid_munged(&init_user_ns, sbi->s_resuid));
2311 	if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2312 	    le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2313 		SEQ_OPTS_PRINT("resgid=%u",
2314 				from_kgid_munged(&init_user_ns, sbi->s_resgid));
2315 	def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2316 	if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2317 		SEQ_OPTS_PUTS("errors=remount-ro");
2318 	if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2319 		SEQ_OPTS_PUTS("errors=continue");
2320 	if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2321 		SEQ_OPTS_PUTS("errors=panic");
2322 	if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2323 		SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2324 	if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2325 		SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2326 	if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2327 		SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2328 	if (sb->s_flags & SB_I_VERSION)
2329 		SEQ_OPTS_PUTS("i_version");
2330 	if (nodefs || sbi->s_stripe)
2331 		SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2332 	if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2333 			(sbi->s_mount_opt ^ def_mount_opt)) {
2334 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2335 			SEQ_OPTS_PUTS("data=journal");
2336 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2337 			SEQ_OPTS_PUTS("data=ordered");
2338 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2339 			SEQ_OPTS_PUTS("data=writeback");
2340 	}
2341 	if (nodefs ||
2342 	    sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2343 		SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2344 			       sbi->s_inode_readahead_blks);
2345 
2346 	if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2347 		       (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2348 		SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2349 	if (nodefs || sbi->s_max_dir_size_kb)
2350 		SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2351 	if (test_opt(sb, DATA_ERR_ABORT))
2352 		SEQ_OPTS_PUTS("data_err=abort");
2353 
2354 	fscrypt_show_test_dummy_encryption(seq, sep, sb);
2355 
2356 	ext4_show_quota_options(seq, sb);
2357 	return 0;
2358 }
2359 
2360 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2361 {
2362 	return _ext4_show_options(seq, root->d_sb, 0);
2363 }
2364 
2365 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2366 {
2367 	struct super_block *sb = seq->private;
2368 	int rc;
2369 
2370 	seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2371 	rc = _ext4_show_options(seq, sb, 1);
2372 	seq_puts(seq, "\n");
2373 	return rc;
2374 }
2375 
2376 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2377 			    int read_only)
2378 {
2379 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2380 	int err = 0;
2381 
2382 	if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2383 		ext4_msg(sb, KERN_ERR, "revision level too high, "
2384 			 "forcing read-only mode");
2385 		err = -EROFS;
2386 	}
2387 	if (read_only)
2388 		goto done;
2389 	if (!(sbi->s_mount_state & EXT4_VALID_FS))
2390 		ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2391 			 "running e2fsck is recommended");
2392 	else if (sbi->s_mount_state & EXT4_ERROR_FS)
2393 		ext4_msg(sb, KERN_WARNING,
2394 			 "warning: mounting fs with errors, "
2395 			 "running e2fsck is recommended");
2396 	else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2397 		 le16_to_cpu(es->s_mnt_count) >=
2398 		 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2399 		ext4_msg(sb, KERN_WARNING,
2400 			 "warning: maximal mount count reached, "
2401 			 "running e2fsck is recommended");
2402 	else if (le32_to_cpu(es->s_checkinterval) &&
2403 		 (ext4_get_tstamp(es, s_lastcheck) +
2404 		  le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2405 		ext4_msg(sb, KERN_WARNING,
2406 			 "warning: checktime reached, "
2407 			 "running e2fsck is recommended");
2408 	if (!sbi->s_journal)
2409 		es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2410 	if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2411 		es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2412 	le16_add_cpu(&es->s_mnt_count, 1);
2413 	ext4_update_tstamp(es, s_mtime);
2414 	if (sbi->s_journal)
2415 		ext4_set_feature_journal_needs_recovery(sb);
2416 
2417 	err = ext4_commit_super(sb, 1);
2418 done:
2419 	if (test_opt(sb, DEBUG))
2420 		printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2421 				"bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2422 			sb->s_blocksize,
2423 			sbi->s_groups_count,
2424 			EXT4_BLOCKS_PER_GROUP(sb),
2425 			EXT4_INODES_PER_GROUP(sb),
2426 			sbi->s_mount_opt, sbi->s_mount_opt2);
2427 
2428 	cleancache_init_fs(sb);
2429 	return err;
2430 }
2431 
2432 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2433 {
2434 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2435 	struct flex_groups **old_groups, **new_groups;
2436 	int size, i, j;
2437 
2438 	if (!sbi->s_log_groups_per_flex)
2439 		return 0;
2440 
2441 	size = ext4_flex_group(sbi, ngroup - 1) + 1;
2442 	if (size <= sbi->s_flex_groups_allocated)
2443 		return 0;
2444 
2445 	new_groups = kvzalloc(roundup_pow_of_two(size *
2446 			      sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2447 	if (!new_groups) {
2448 		ext4_msg(sb, KERN_ERR,
2449 			 "not enough memory for %d flex group pointers", size);
2450 		return -ENOMEM;
2451 	}
2452 	for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2453 		new_groups[i] = kvzalloc(roundup_pow_of_two(
2454 					 sizeof(struct flex_groups)),
2455 					 GFP_KERNEL);
2456 		if (!new_groups[i]) {
2457 			for (j = sbi->s_flex_groups_allocated; j < i; j++)
2458 				kvfree(new_groups[j]);
2459 			kvfree(new_groups);
2460 			ext4_msg(sb, KERN_ERR,
2461 				 "not enough memory for %d flex groups", size);
2462 			return -ENOMEM;
2463 		}
2464 	}
2465 	rcu_read_lock();
2466 	old_groups = rcu_dereference(sbi->s_flex_groups);
2467 	if (old_groups)
2468 		memcpy(new_groups, old_groups,
2469 		       (sbi->s_flex_groups_allocated *
2470 			sizeof(struct flex_groups *)));
2471 	rcu_read_unlock();
2472 	rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2473 	sbi->s_flex_groups_allocated = size;
2474 	if (old_groups)
2475 		ext4_kvfree_array_rcu(old_groups);
2476 	return 0;
2477 }
2478 
2479 static int ext4_fill_flex_info(struct super_block *sb)
2480 {
2481 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2482 	struct ext4_group_desc *gdp = NULL;
2483 	struct flex_groups *fg;
2484 	ext4_group_t flex_group;
2485 	int i, err;
2486 
2487 	sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2488 	if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2489 		sbi->s_log_groups_per_flex = 0;
2490 		return 1;
2491 	}
2492 
2493 	err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2494 	if (err)
2495 		goto failed;
2496 
2497 	for (i = 0; i < sbi->s_groups_count; i++) {
2498 		gdp = ext4_get_group_desc(sb, i, NULL);
2499 
2500 		flex_group = ext4_flex_group(sbi, i);
2501 		fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2502 		atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2503 		atomic64_add(ext4_free_group_clusters(sb, gdp),
2504 			     &fg->free_clusters);
2505 		atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2506 	}
2507 
2508 	return 1;
2509 failed:
2510 	return 0;
2511 }
2512 
2513 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2514 				   struct ext4_group_desc *gdp)
2515 {
2516 	int offset = offsetof(struct ext4_group_desc, bg_checksum);
2517 	__u16 crc = 0;
2518 	__le32 le_group = cpu_to_le32(block_group);
2519 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2520 
2521 	if (ext4_has_metadata_csum(sbi->s_sb)) {
2522 		/* Use new metadata_csum algorithm */
2523 		__u32 csum32;
2524 		__u16 dummy_csum = 0;
2525 
2526 		csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2527 				     sizeof(le_group));
2528 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2529 		csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2530 				     sizeof(dummy_csum));
2531 		offset += sizeof(dummy_csum);
2532 		if (offset < sbi->s_desc_size)
2533 			csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2534 					     sbi->s_desc_size - offset);
2535 
2536 		crc = csum32 & 0xFFFF;
2537 		goto out;
2538 	}
2539 
2540 	/* old crc16 code */
2541 	if (!ext4_has_feature_gdt_csum(sb))
2542 		return 0;
2543 
2544 	crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2545 	crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2546 	crc = crc16(crc, (__u8 *)gdp, offset);
2547 	offset += sizeof(gdp->bg_checksum); /* skip checksum */
2548 	/* for checksum of struct ext4_group_desc do the rest...*/
2549 	if (ext4_has_feature_64bit(sb) &&
2550 	    offset < le16_to_cpu(sbi->s_es->s_desc_size))
2551 		crc = crc16(crc, (__u8 *)gdp + offset,
2552 			    le16_to_cpu(sbi->s_es->s_desc_size) -
2553 				offset);
2554 
2555 out:
2556 	return cpu_to_le16(crc);
2557 }
2558 
2559 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2560 				struct ext4_group_desc *gdp)
2561 {
2562 	if (ext4_has_group_desc_csum(sb) &&
2563 	    (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2564 		return 0;
2565 
2566 	return 1;
2567 }
2568 
2569 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2570 			      struct ext4_group_desc *gdp)
2571 {
2572 	if (!ext4_has_group_desc_csum(sb))
2573 		return;
2574 	gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2575 }
2576 
2577 /* Called at mount-time, super-block is locked */
2578 static int ext4_check_descriptors(struct super_block *sb,
2579 				  ext4_fsblk_t sb_block,
2580 				  ext4_group_t *first_not_zeroed)
2581 {
2582 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2583 	ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2584 	ext4_fsblk_t last_block;
2585 	ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2586 	ext4_fsblk_t block_bitmap;
2587 	ext4_fsblk_t inode_bitmap;
2588 	ext4_fsblk_t inode_table;
2589 	int flexbg_flag = 0;
2590 	ext4_group_t i, grp = sbi->s_groups_count;
2591 
2592 	if (ext4_has_feature_flex_bg(sb))
2593 		flexbg_flag = 1;
2594 
2595 	ext4_debug("Checking group descriptors");
2596 
2597 	for (i = 0; i < sbi->s_groups_count; i++) {
2598 		struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2599 
2600 		if (i == sbi->s_groups_count - 1 || flexbg_flag)
2601 			last_block = ext4_blocks_count(sbi->s_es) - 1;
2602 		else
2603 			last_block = first_block +
2604 				(EXT4_BLOCKS_PER_GROUP(sb) - 1);
2605 
2606 		if ((grp == sbi->s_groups_count) &&
2607 		   !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2608 			grp = i;
2609 
2610 		block_bitmap = ext4_block_bitmap(sb, gdp);
2611 		if (block_bitmap == sb_block) {
2612 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2613 				 "Block bitmap for group %u overlaps "
2614 				 "superblock", i);
2615 			if (!sb_rdonly(sb))
2616 				return 0;
2617 		}
2618 		if (block_bitmap >= sb_block + 1 &&
2619 		    block_bitmap <= last_bg_block) {
2620 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2621 				 "Block bitmap for group %u overlaps "
2622 				 "block group descriptors", i);
2623 			if (!sb_rdonly(sb))
2624 				return 0;
2625 		}
2626 		if (block_bitmap < first_block || block_bitmap > last_block) {
2627 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2628 			       "Block bitmap for group %u not in group "
2629 			       "(block %llu)!", i, block_bitmap);
2630 			return 0;
2631 		}
2632 		inode_bitmap = ext4_inode_bitmap(sb, gdp);
2633 		if (inode_bitmap == sb_block) {
2634 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2635 				 "Inode bitmap for group %u overlaps "
2636 				 "superblock", i);
2637 			if (!sb_rdonly(sb))
2638 				return 0;
2639 		}
2640 		if (inode_bitmap >= sb_block + 1 &&
2641 		    inode_bitmap <= last_bg_block) {
2642 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2643 				 "Inode bitmap for group %u overlaps "
2644 				 "block group descriptors", i);
2645 			if (!sb_rdonly(sb))
2646 				return 0;
2647 		}
2648 		if (inode_bitmap < first_block || inode_bitmap > last_block) {
2649 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2650 			       "Inode bitmap for group %u not in group "
2651 			       "(block %llu)!", i, inode_bitmap);
2652 			return 0;
2653 		}
2654 		inode_table = ext4_inode_table(sb, gdp);
2655 		if (inode_table == sb_block) {
2656 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2657 				 "Inode table for group %u overlaps "
2658 				 "superblock", i);
2659 			if (!sb_rdonly(sb))
2660 				return 0;
2661 		}
2662 		if (inode_table >= sb_block + 1 &&
2663 		    inode_table <= last_bg_block) {
2664 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2665 				 "Inode table for group %u overlaps "
2666 				 "block group descriptors", i);
2667 			if (!sb_rdonly(sb))
2668 				return 0;
2669 		}
2670 		if (inode_table < first_block ||
2671 		    inode_table + sbi->s_itb_per_group - 1 > last_block) {
2672 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2673 			       "Inode table for group %u not in group "
2674 			       "(block %llu)!", i, inode_table);
2675 			return 0;
2676 		}
2677 		ext4_lock_group(sb, i);
2678 		if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2679 			ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2680 				 "Checksum for group %u failed (%u!=%u)",
2681 				 i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2682 				     gdp)), le16_to_cpu(gdp->bg_checksum));
2683 			if (!sb_rdonly(sb)) {
2684 				ext4_unlock_group(sb, i);
2685 				return 0;
2686 			}
2687 		}
2688 		ext4_unlock_group(sb, i);
2689 		if (!flexbg_flag)
2690 			first_block += EXT4_BLOCKS_PER_GROUP(sb);
2691 	}
2692 	if (NULL != first_not_zeroed)
2693 		*first_not_zeroed = grp;
2694 	return 1;
2695 }
2696 
2697 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2698  * the superblock) which were deleted from all directories, but held open by
2699  * a process at the time of a crash.  We walk the list and try to delete these
2700  * inodes at recovery time (only with a read-write filesystem).
2701  *
2702  * In order to keep the orphan inode chain consistent during traversal (in
2703  * case of crash during recovery), we link each inode into the superblock
2704  * orphan list_head and handle it the same way as an inode deletion during
2705  * normal operation (which journals the operations for us).
2706  *
2707  * We only do an iget() and an iput() on each inode, which is very safe if we
2708  * accidentally point at an in-use or already deleted inode.  The worst that
2709  * can happen in this case is that we get a "bit already cleared" message from
2710  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2711  * e2fsck was run on this filesystem, and it must have already done the orphan
2712  * inode cleanup for us, so we can safely abort without any further action.
2713  */
2714 static void ext4_orphan_cleanup(struct super_block *sb,
2715 				struct ext4_super_block *es)
2716 {
2717 	unsigned int s_flags = sb->s_flags;
2718 	int ret, nr_orphans = 0, nr_truncates = 0;
2719 #ifdef CONFIG_QUOTA
2720 	int quota_update = 0;
2721 	int i;
2722 #endif
2723 	if (!es->s_last_orphan) {
2724 		jbd_debug(4, "no orphan inodes to clean up\n");
2725 		return;
2726 	}
2727 
2728 	if (bdev_read_only(sb->s_bdev)) {
2729 		ext4_msg(sb, KERN_ERR, "write access "
2730 			"unavailable, skipping orphan cleanup");
2731 		return;
2732 	}
2733 
2734 	/* Check if feature set would not allow a r/w mount */
2735 	if (!ext4_feature_set_ok(sb, 0)) {
2736 		ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2737 			 "unknown ROCOMPAT features");
2738 		return;
2739 	}
2740 
2741 	if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2742 		/* don't clear list on RO mount w/ errors */
2743 		if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2744 			ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2745 				  "clearing orphan list.\n");
2746 			es->s_last_orphan = 0;
2747 		}
2748 		jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2749 		return;
2750 	}
2751 
2752 	if (s_flags & SB_RDONLY) {
2753 		ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2754 		sb->s_flags &= ~SB_RDONLY;
2755 	}
2756 #ifdef CONFIG_QUOTA
2757 	/* Needed for iput() to work correctly and not trash data */
2758 	sb->s_flags |= SB_ACTIVE;
2759 
2760 	/*
2761 	 * Turn on quotas which were not enabled for read-only mounts if
2762 	 * filesystem has quota feature, so that they are updated correctly.
2763 	 */
2764 	if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2765 		int ret = ext4_enable_quotas(sb);
2766 
2767 		if (!ret)
2768 			quota_update = 1;
2769 		else
2770 			ext4_msg(sb, KERN_ERR,
2771 				"Cannot turn on quotas: error %d", ret);
2772 	}
2773 
2774 	/* Turn on journaled quotas used for old sytle */
2775 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2776 		if (EXT4_SB(sb)->s_qf_names[i]) {
2777 			int ret = ext4_quota_on_mount(sb, i);
2778 
2779 			if (!ret)
2780 				quota_update = 1;
2781 			else
2782 				ext4_msg(sb, KERN_ERR,
2783 					"Cannot turn on journaled "
2784 					"quota: type %d: error %d", i, ret);
2785 		}
2786 	}
2787 #endif
2788 
2789 	while (es->s_last_orphan) {
2790 		struct inode *inode;
2791 
2792 		/*
2793 		 * We may have encountered an error during cleanup; if
2794 		 * so, skip the rest.
2795 		 */
2796 		if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2797 			jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2798 			es->s_last_orphan = 0;
2799 			break;
2800 		}
2801 
2802 		inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2803 		if (IS_ERR(inode)) {
2804 			es->s_last_orphan = 0;
2805 			break;
2806 		}
2807 
2808 		list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2809 		dquot_initialize(inode);
2810 		if (inode->i_nlink) {
2811 			if (test_opt(sb, DEBUG))
2812 				ext4_msg(sb, KERN_DEBUG,
2813 					"%s: truncating inode %lu to %lld bytes",
2814 					__func__, inode->i_ino, inode->i_size);
2815 			jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2816 				  inode->i_ino, inode->i_size);
2817 			inode_lock(inode);
2818 			truncate_inode_pages(inode->i_mapping, inode->i_size);
2819 			ret = ext4_truncate(inode);
2820 			if (ret)
2821 				ext4_std_error(inode->i_sb, ret);
2822 			inode_unlock(inode);
2823 			nr_truncates++;
2824 		} else {
2825 			if (test_opt(sb, DEBUG))
2826 				ext4_msg(sb, KERN_DEBUG,
2827 					"%s: deleting unreferenced inode %lu",
2828 					__func__, inode->i_ino);
2829 			jbd_debug(2, "deleting unreferenced inode %lu\n",
2830 				  inode->i_ino);
2831 			nr_orphans++;
2832 		}
2833 		iput(inode);  /* The delete magic happens here! */
2834 	}
2835 
2836 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2837 
2838 	if (nr_orphans)
2839 		ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2840 		       PLURAL(nr_orphans));
2841 	if (nr_truncates)
2842 		ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2843 		       PLURAL(nr_truncates));
2844 #ifdef CONFIG_QUOTA
2845 	/* Turn off quotas if they were enabled for orphan cleanup */
2846 	if (quota_update) {
2847 		for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2848 			if (sb_dqopt(sb)->files[i])
2849 				dquot_quota_off(sb, i);
2850 		}
2851 	}
2852 #endif
2853 	sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2854 }
2855 
2856 /*
2857  * Maximal extent format file size.
2858  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2859  * extent format containers, within a sector_t, and within i_blocks
2860  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2861  * so that won't be a limiting factor.
2862  *
2863  * However there is other limiting factor. We do store extents in the form
2864  * of starting block and length, hence the resulting length of the extent
2865  * covering maximum file size must fit into on-disk format containers as
2866  * well. Given that length is always by 1 unit bigger than max unit (because
2867  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2868  *
2869  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2870  */
2871 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2872 {
2873 	loff_t res;
2874 	loff_t upper_limit = MAX_LFS_FILESIZE;
2875 
2876 	BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2877 
2878 	if (!has_huge_files) {
2879 		upper_limit = (1LL << 32) - 1;
2880 
2881 		/* total blocks in file system block size */
2882 		upper_limit >>= (blkbits - 9);
2883 		upper_limit <<= blkbits;
2884 	}
2885 
2886 	/*
2887 	 * 32-bit extent-start container, ee_block. We lower the maxbytes
2888 	 * by one fs block, so ee_len can cover the extent of maximum file
2889 	 * size
2890 	 */
2891 	res = (1LL << 32) - 1;
2892 	res <<= blkbits;
2893 
2894 	/* Sanity check against vm- & vfs- imposed limits */
2895 	if (res > upper_limit)
2896 		res = upper_limit;
2897 
2898 	return res;
2899 }
2900 
2901 /*
2902  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2903  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2904  * We need to be 1 filesystem block less than the 2^48 sector limit.
2905  */
2906 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2907 {
2908 	loff_t res = EXT4_NDIR_BLOCKS;
2909 	int meta_blocks;
2910 	loff_t upper_limit;
2911 	/* This is calculated to be the largest file size for a dense, block
2912 	 * mapped file such that the file's total number of 512-byte sectors,
2913 	 * including data and all indirect blocks, does not exceed (2^48 - 1).
2914 	 *
2915 	 * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2916 	 * number of 512-byte sectors of the file.
2917 	 */
2918 
2919 	if (!has_huge_files) {
2920 		/*
2921 		 * !has_huge_files or implies that the inode i_block field
2922 		 * represents total file blocks in 2^32 512-byte sectors ==
2923 		 * size of vfs inode i_blocks * 8
2924 		 */
2925 		upper_limit = (1LL << 32) - 1;
2926 
2927 		/* total blocks in file system block size */
2928 		upper_limit >>= (bits - 9);
2929 
2930 	} else {
2931 		/*
2932 		 * We use 48 bit ext4_inode i_blocks
2933 		 * With EXT4_HUGE_FILE_FL set the i_blocks
2934 		 * represent total number of blocks in
2935 		 * file system block size
2936 		 */
2937 		upper_limit = (1LL << 48) - 1;
2938 
2939 	}
2940 
2941 	/* indirect blocks */
2942 	meta_blocks = 1;
2943 	/* double indirect blocks */
2944 	meta_blocks += 1 + (1LL << (bits-2));
2945 	/* tripple indirect blocks */
2946 	meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2947 
2948 	upper_limit -= meta_blocks;
2949 	upper_limit <<= bits;
2950 
2951 	res += 1LL << (bits-2);
2952 	res += 1LL << (2*(bits-2));
2953 	res += 1LL << (3*(bits-2));
2954 	res <<= bits;
2955 	if (res > upper_limit)
2956 		res = upper_limit;
2957 
2958 	if (res > MAX_LFS_FILESIZE)
2959 		res = MAX_LFS_FILESIZE;
2960 
2961 	return res;
2962 }
2963 
2964 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2965 				   ext4_fsblk_t logical_sb_block, int nr)
2966 {
2967 	struct ext4_sb_info *sbi = EXT4_SB(sb);
2968 	ext4_group_t bg, first_meta_bg;
2969 	int has_super = 0;
2970 
2971 	first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2972 
2973 	if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2974 		return logical_sb_block + nr + 1;
2975 	bg = sbi->s_desc_per_block * nr;
2976 	if (ext4_bg_has_super(sb, bg))
2977 		has_super = 1;
2978 
2979 	/*
2980 	 * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2981 	 * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2982 	 * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2983 	 * compensate.
2984 	 */
2985 	if (sb->s_blocksize == 1024 && nr == 0 &&
2986 	    le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2987 		has_super++;
2988 
2989 	return (has_super + ext4_group_first_block_no(sb, bg));
2990 }
2991 
2992 /**
2993  * ext4_get_stripe_size: Get the stripe size.
2994  * @sbi: In memory super block info
2995  *
2996  * If we have specified it via mount option, then
2997  * use the mount option value. If the value specified at mount time is
2998  * greater than the blocks per group use the super block value.
2999  * If the super block value is greater than blocks per group return 0.
3000  * Allocator needs it be less than blocks per group.
3001  *
3002  */
3003 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3004 {
3005 	unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3006 	unsigned long stripe_width =
3007 			le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3008 	int ret;
3009 
3010 	if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3011 		ret = sbi->s_stripe;
3012 	else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3013 		ret = stripe_width;
3014 	else if (stride && stride <= sbi->s_blocks_per_group)
3015 		ret = stride;
3016 	else
3017 		ret = 0;
3018 
3019 	/*
3020 	 * If the stripe width is 1, this makes no sense and
3021 	 * we set it to 0 to turn off stripe handling code.
3022 	 */
3023 	if (ret <= 1)
3024 		ret = 0;
3025 
3026 	return ret;
3027 }
3028 
3029 /*
3030  * Check whether this filesystem can be mounted based on
3031  * the features present and the RDONLY/RDWR mount requested.
3032  * Returns 1 if this filesystem can be mounted as requested,
3033  * 0 if it cannot be.
3034  */
3035 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3036 {
3037 	if (ext4_has_unknown_ext4_incompat_features(sb)) {
3038 		ext4_msg(sb, KERN_ERR,
3039 			"Couldn't mount because of "
3040 			"unsupported optional features (%x)",
3041 			(le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3042 			~EXT4_FEATURE_INCOMPAT_SUPP));
3043 		return 0;
3044 	}
3045 
3046 #ifndef CONFIG_UNICODE
3047 	if (ext4_has_feature_casefold(sb)) {
3048 		ext4_msg(sb, KERN_ERR,
3049 			 "Filesystem with casefold feature cannot be "
3050 			 "mounted without CONFIG_UNICODE");
3051 		return 0;
3052 	}
3053 #endif
3054 
3055 	if (readonly)
3056 		return 1;
3057 
3058 	if (ext4_has_feature_readonly(sb)) {
3059 		ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3060 		sb->s_flags |= SB_RDONLY;
3061 		return 1;
3062 	}
3063 
3064 	/* Check that feature set is OK for a read-write mount */
3065 	if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3066 		ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3067 			 "unsupported optional features (%x)",
3068 			 (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3069 				~EXT4_FEATURE_RO_COMPAT_SUPP));
3070 		return 0;
3071 	}
3072 	if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3073 		ext4_msg(sb, KERN_ERR,
3074 			 "Can't support bigalloc feature without "
3075 			 "extents feature\n");
3076 		return 0;
3077 	}
3078 
3079 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3080 	if (!readonly && (ext4_has_feature_quota(sb) ||
3081 			  ext4_has_feature_project(sb))) {
3082 		ext4_msg(sb, KERN_ERR,
3083 			 "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3084 		return 0;
3085 	}
3086 #endif  /* CONFIG_QUOTA */
3087 	return 1;
3088 }
3089 
3090 /*
3091  * This function is called once a day if we have errors logged
3092  * on the file system
3093  */
3094 static void print_daily_error_info(struct timer_list *t)
3095 {
3096 	struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3097 	struct super_block *sb = sbi->s_sb;
3098 	struct ext4_super_block *es = sbi->s_es;
3099 
3100 	if (es->s_error_count)
3101 		/* fsck newer than v1.41.13 is needed to clean this condition. */
3102 		ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3103 			 le32_to_cpu(es->s_error_count));
3104 	if (es->s_first_error_time) {
3105 		printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3106 		       sb->s_id,
3107 		       ext4_get_tstamp(es, s_first_error_time),
3108 		       (int) sizeof(es->s_first_error_func),
3109 		       es->s_first_error_func,
3110 		       le32_to_cpu(es->s_first_error_line));
3111 		if (es->s_first_error_ino)
3112 			printk(KERN_CONT ": inode %u",
3113 			       le32_to_cpu(es->s_first_error_ino));
3114 		if (es->s_first_error_block)
3115 			printk(KERN_CONT ": block %llu", (unsigned long long)
3116 			       le64_to_cpu(es->s_first_error_block));
3117 		printk(KERN_CONT "\n");
3118 	}
3119 	if (es->s_last_error_time) {
3120 		printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3121 		       sb->s_id,
3122 		       ext4_get_tstamp(es, s_last_error_time),
3123 		       (int) sizeof(es->s_last_error_func),
3124 		       es->s_last_error_func,
3125 		       le32_to_cpu(es->s_last_error_line));
3126 		if (es->s_last_error_ino)
3127 			printk(KERN_CONT ": inode %u",
3128 			       le32_to_cpu(es->s_last_error_ino));
3129 		if (es->s_last_error_block)
3130 			printk(KERN_CONT ": block %llu", (unsigned long long)
3131 			       le64_to_cpu(es->s_last_error_block));
3132 		printk(KERN_CONT "\n");
3133 	}
3134 	mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3135 }
3136 
3137 /* Find next suitable group and run ext4_init_inode_table */
3138 static int ext4_run_li_request(struct ext4_li_request *elr)
3139 {
3140 	struct ext4_group_desc *gdp = NULL;
3141 	ext4_group_t group, ngroups;
3142 	struct super_block *sb;
3143 	unsigned long timeout = 0;
3144 	int ret = 0;
3145 
3146 	sb = elr->lr_super;
3147 	ngroups = EXT4_SB(sb)->s_groups_count;
3148 
3149 	for (group = elr->lr_next_group; group < ngroups; group++) {
3150 		gdp = ext4_get_group_desc(sb, group, NULL);
3151 		if (!gdp) {
3152 			ret = 1;
3153 			break;
3154 		}
3155 
3156 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3157 			break;
3158 	}
3159 
3160 	if (group >= ngroups)
3161 		ret = 1;
3162 
3163 	if (!ret) {
3164 		timeout = jiffies;
3165 		ret = ext4_init_inode_table(sb, group,
3166 					    elr->lr_timeout ? 0 : 1);
3167 		if (elr->lr_timeout == 0) {
3168 			timeout = (jiffies - timeout) *
3169 				  elr->lr_sbi->s_li_wait_mult;
3170 			elr->lr_timeout = timeout;
3171 		}
3172 		elr->lr_next_sched = jiffies + elr->lr_timeout;
3173 		elr->lr_next_group = group + 1;
3174 	}
3175 	return ret;
3176 }
3177 
3178 /*
3179  * Remove lr_request from the list_request and free the
3180  * request structure. Should be called with li_list_mtx held
3181  */
3182 static void ext4_remove_li_request(struct ext4_li_request *elr)
3183 {
3184 	struct ext4_sb_info *sbi;
3185 
3186 	if (!elr)
3187 		return;
3188 
3189 	sbi = elr->lr_sbi;
3190 
3191 	list_del(&elr->lr_request);
3192 	sbi->s_li_request = NULL;
3193 	kfree(elr);
3194 }
3195 
3196 static void ext4_unregister_li_request(struct super_block *sb)
3197 {
3198 	mutex_lock(&ext4_li_mtx);
3199 	if (!ext4_li_info) {
3200 		mutex_unlock(&ext4_li_mtx);
3201 		return;
3202 	}
3203 
3204 	mutex_lock(&ext4_li_info->li_list_mtx);
3205 	ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3206 	mutex_unlock(&ext4_li_info->li_list_mtx);
3207 	mutex_unlock(&ext4_li_mtx);
3208 }
3209 
3210 static struct task_struct *ext4_lazyinit_task;
3211 
3212 /*
3213  * This is the function where ext4lazyinit thread lives. It walks
3214  * through the request list searching for next scheduled filesystem.
3215  * When such a fs is found, run the lazy initialization request
3216  * (ext4_rn_li_request) and keep track of the time spend in this
3217  * function. Based on that time we compute next schedule time of
3218  * the request. When walking through the list is complete, compute
3219  * next waking time and put itself into sleep.
3220  */
3221 static int ext4_lazyinit_thread(void *arg)
3222 {
3223 	struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3224 	struct list_head *pos, *n;
3225 	struct ext4_li_request *elr;
3226 	unsigned long next_wakeup, cur;
3227 
3228 	BUG_ON(NULL == eli);
3229 
3230 cont_thread:
3231 	while (true) {
3232 		next_wakeup = MAX_JIFFY_OFFSET;
3233 
3234 		mutex_lock(&eli->li_list_mtx);
3235 		if (list_empty(&eli->li_request_list)) {
3236 			mutex_unlock(&eli->li_list_mtx);
3237 			goto exit_thread;
3238 		}
3239 		list_for_each_safe(pos, n, &eli->li_request_list) {
3240 			int err = 0;
3241 			int progress = 0;
3242 			elr = list_entry(pos, struct ext4_li_request,
3243 					 lr_request);
3244 
3245 			if (time_before(jiffies, elr->lr_next_sched)) {
3246 				if (time_before(elr->lr_next_sched, next_wakeup))
3247 					next_wakeup = elr->lr_next_sched;
3248 				continue;
3249 			}
3250 			if (down_read_trylock(&elr->lr_super->s_umount)) {
3251 				if (sb_start_write_trylock(elr->lr_super)) {
3252 					progress = 1;
3253 					/*
3254 					 * We hold sb->s_umount, sb can not
3255 					 * be removed from the list, it is
3256 					 * now safe to drop li_list_mtx
3257 					 */
3258 					mutex_unlock(&eli->li_list_mtx);
3259 					err = ext4_run_li_request(elr);
3260 					sb_end_write(elr->lr_super);
3261 					mutex_lock(&eli->li_list_mtx);
3262 					n = pos->next;
3263 				}
3264 				up_read((&elr->lr_super->s_umount));
3265 			}
3266 			/* error, remove the lazy_init job */
3267 			if (err) {
3268 				ext4_remove_li_request(elr);
3269 				continue;
3270 			}
3271 			if (!progress) {
3272 				elr->lr_next_sched = jiffies +
3273 					(prandom_u32()
3274 					 % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3275 			}
3276 			if (time_before(elr->lr_next_sched, next_wakeup))
3277 				next_wakeup = elr->lr_next_sched;
3278 		}
3279 		mutex_unlock(&eli->li_list_mtx);
3280 
3281 		try_to_freeze();
3282 
3283 		cur = jiffies;
3284 		if ((time_after_eq(cur, next_wakeup)) ||
3285 		    (MAX_JIFFY_OFFSET == next_wakeup)) {
3286 			cond_resched();
3287 			continue;
3288 		}
3289 
3290 		schedule_timeout_interruptible(next_wakeup - cur);
3291 
3292 		if (kthread_should_stop()) {
3293 			ext4_clear_request_list();
3294 			goto exit_thread;
3295 		}
3296 	}
3297 
3298 exit_thread:
3299 	/*
3300 	 * It looks like the request list is empty, but we need
3301 	 * to check it under the li_list_mtx lock, to prevent any
3302 	 * additions into it, and of course we should lock ext4_li_mtx
3303 	 * to atomically free the list and ext4_li_info, because at
3304 	 * this point another ext4 filesystem could be registering
3305 	 * new one.
3306 	 */
3307 	mutex_lock(&ext4_li_mtx);
3308 	mutex_lock(&eli->li_list_mtx);
3309 	if (!list_empty(&eli->li_request_list)) {
3310 		mutex_unlock(&eli->li_list_mtx);
3311 		mutex_unlock(&ext4_li_mtx);
3312 		goto cont_thread;
3313 	}
3314 	mutex_unlock(&eli->li_list_mtx);
3315 	kfree(ext4_li_info);
3316 	ext4_li_info = NULL;
3317 	mutex_unlock(&ext4_li_mtx);
3318 
3319 	return 0;
3320 }
3321 
3322 static void ext4_clear_request_list(void)
3323 {
3324 	struct list_head *pos, *n;
3325 	struct ext4_li_request *elr;
3326 
3327 	mutex_lock(&ext4_li_info->li_list_mtx);
3328 	list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3329 		elr = list_entry(pos, struct ext4_li_request,
3330 				 lr_request);
3331 		ext4_remove_li_request(elr);
3332 	}
3333 	mutex_unlock(&ext4_li_info->li_list_mtx);
3334 }
3335 
3336 static int ext4_run_lazyinit_thread(void)
3337 {
3338 	ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3339 					 ext4_li_info, "ext4lazyinit");
3340 	if (IS_ERR(ext4_lazyinit_task)) {
3341 		int err = PTR_ERR(ext4_lazyinit_task);
3342 		ext4_clear_request_list();
3343 		kfree(ext4_li_info);
3344 		ext4_li_info = NULL;
3345 		printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3346 				 "initialization thread\n",
3347 				 err);
3348 		return err;
3349 	}
3350 	ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3351 	return 0;
3352 }
3353 
3354 /*
3355  * Check whether it make sense to run itable init. thread or not.
3356  * If there is at least one uninitialized inode table, return
3357  * corresponding group number, else the loop goes through all
3358  * groups and return total number of groups.
3359  */
3360 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3361 {
3362 	ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3363 	struct ext4_group_desc *gdp = NULL;
3364 
3365 	if (!ext4_has_group_desc_csum(sb))
3366 		return ngroups;
3367 
3368 	for (group = 0; group < ngroups; group++) {
3369 		gdp = ext4_get_group_desc(sb, group, NULL);
3370 		if (!gdp)
3371 			continue;
3372 
3373 		if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3374 			break;
3375 	}
3376 
3377 	return group;
3378 }
3379 
3380 static int ext4_li_info_new(void)
3381 {
3382 	struct ext4_lazy_init *eli = NULL;
3383 
3384 	eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3385 	if (!eli)
3386 		return -ENOMEM;
3387 
3388 	INIT_LIST_HEAD(&eli->li_request_list);
3389 	mutex_init(&eli->li_list_mtx);
3390 
3391 	eli->li_state |= EXT4_LAZYINIT_QUIT;
3392 
3393 	ext4_li_info = eli;
3394 
3395 	return 0;
3396 }
3397 
3398 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3399 					    ext4_group_t start)
3400 {
3401 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3402 	struct ext4_li_request *elr;
3403 
3404 	elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3405 	if (!elr)
3406 		return NULL;
3407 
3408 	elr->lr_super = sb;
3409 	elr->lr_sbi = sbi;
3410 	elr->lr_next_group = start;
3411 
3412 	/*
3413 	 * Randomize first schedule time of the request to
3414 	 * spread the inode table initialization requests
3415 	 * better.
3416 	 */
3417 	elr->lr_next_sched = jiffies + (prandom_u32() %
3418 				(EXT4_DEF_LI_MAX_START_DELAY * HZ));
3419 	return elr;
3420 }
3421 
3422 int ext4_register_li_request(struct super_block *sb,
3423 			     ext4_group_t first_not_zeroed)
3424 {
3425 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3426 	struct ext4_li_request *elr = NULL;
3427 	ext4_group_t ngroups = sbi->s_groups_count;
3428 	int ret = 0;
3429 
3430 	mutex_lock(&ext4_li_mtx);
3431 	if (sbi->s_li_request != NULL) {
3432 		/*
3433 		 * Reset timeout so it can be computed again, because
3434 		 * s_li_wait_mult might have changed.
3435 		 */
3436 		sbi->s_li_request->lr_timeout = 0;
3437 		goto out;
3438 	}
3439 
3440 	if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3441 	    !test_opt(sb, INIT_INODE_TABLE))
3442 		goto out;
3443 
3444 	elr = ext4_li_request_new(sb, first_not_zeroed);
3445 	if (!elr) {
3446 		ret = -ENOMEM;
3447 		goto out;
3448 	}
3449 
3450 	if (NULL == ext4_li_info) {
3451 		ret = ext4_li_info_new();
3452 		if (ret)
3453 			goto out;
3454 	}
3455 
3456 	mutex_lock(&ext4_li_info->li_list_mtx);
3457 	list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3458 	mutex_unlock(&ext4_li_info->li_list_mtx);
3459 
3460 	sbi->s_li_request = elr;
3461 	/*
3462 	 * set elr to NULL here since it has been inserted to
3463 	 * the request_list and the removal and free of it is
3464 	 * handled by ext4_clear_request_list from now on.
3465 	 */
3466 	elr = NULL;
3467 
3468 	if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3469 		ret = ext4_run_lazyinit_thread();
3470 		if (ret)
3471 			goto out;
3472 	}
3473 out:
3474 	mutex_unlock(&ext4_li_mtx);
3475 	if (ret)
3476 		kfree(elr);
3477 	return ret;
3478 }
3479 
3480 /*
3481  * We do not need to lock anything since this is called on
3482  * module unload.
3483  */
3484 static void ext4_destroy_lazyinit_thread(void)
3485 {
3486 	/*
3487 	 * If thread exited earlier
3488 	 * there's nothing to be done.
3489 	 */
3490 	if (!ext4_li_info || !ext4_lazyinit_task)
3491 		return;
3492 
3493 	kthread_stop(ext4_lazyinit_task);
3494 }
3495 
3496 static int set_journal_csum_feature_set(struct super_block *sb)
3497 {
3498 	int ret = 1;
3499 	int compat, incompat;
3500 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3501 
3502 	if (ext4_has_metadata_csum(sb)) {
3503 		/* journal checksum v3 */
3504 		compat = 0;
3505 		incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3506 	} else {
3507 		/* journal checksum v1 */
3508 		compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3509 		incompat = 0;
3510 	}
3511 
3512 	jbd2_journal_clear_features(sbi->s_journal,
3513 			JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3514 			JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3515 			JBD2_FEATURE_INCOMPAT_CSUM_V2);
3516 	if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3517 		ret = jbd2_journal_set_features(sbi->s_journal,
3518 				compat, 0,
3519 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3520 				incompat);
3521 	} else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3522 		ret = jbd2_journal_set_features(sbi->s_journal,
3523 				compat, 0,
3524 				incompat);
3525 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3526 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3527 	} else {
3528 		jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3529 				JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3530 	}
3531 
3532 	return ret;
3533 }
3534 
3535 /*
3536  * Note: calculating the overhead so we can be compatible with
3537  * historical BSD practice is quite difficult in the face of
3538  * clusters/bigalloc.  This is because multiple metadata blocks from
3539  * different block group can end up in the same allocation cluster.
3540  * Calculating the exact overhead in the face of clustered allocation
3541  * requires either O(all block bitmaps) in memory or O(number of block
3542  * groups**2) in time.  We will still calculate the superblock for
3543  * older file systems --- and if we come across with a bigalloc file
3544  * system with zero in s_overhead_clusters the estimate will be close to
3545  * correct especially for very large cluster sizes --- but for newer
3546  * file systems, it's better to calculate this figure once at mkfs
3547  * time, and store it in the superblock.  If the superblock value is
3548  * present (even for non-bigalloc file systems), we will use it.
3549  */
3550 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3551 			  char *buf)
3552 {
3553 	struct ext4_sb_info	*sbi = EXT4_SB(sb);
3554 	struct ext4_group_desc	*gdp;
3555 	ext4_fsblk_t		first_block, last_block, b;
3556 	ext4_group_t		i, ngroups = ext4_get_groups_count(sb);
3557 	int			s, j, count = 0;
3558 
3559 	if (!ext4_has_feature_bigalloc(sb))
3560 		return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3561 			sbi->s_itb_per_group + 2);
3562 
3563 	first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3564 		(grp * EXT4_BLOCKS_PER_GROUP(sb));
3565 	last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3566 	for (i = 0; i < ngroups; i++) {
3567 		gdp = ext4_get_group_desc(sb, i, NULL);
3568 		b = ext4_block_bitmap(sb, gdp);
3569 		if (b >= first_block && b <= last_block) {
3570 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3571 			count++;
3572 		}
3573 		b = ext4_inode_bitmap(sb, gdp);
3574 		if (b >= first_block && b <= last_block) {
3575 			ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3576 			count++;
3577 		}
3578 		b = ext4_inode_table(sb, gdp);
3579 		if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3580 			for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3581 				int c = EXT4_B2C(sbi, b - first_block);
3582 				ext4_set_bit(c, buf);
3583 				count++;
3584 			}
3585 		if (i != grp)
3586 			continue;
3587 		s = 0;
3588 		if (ext4_bg_has_super(sb, grp)) {
3589 			ext4_set_bit(s++, buf);
3590 			count++;
3591 		}
3592 		j = ext4_bg_num_gdb(sb, grp);
3593 		if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3594 			ext4_error(sb, "Invalid number of block group "
3595 				   "descriptor blocks: %d", j);
3596 			j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3597 		}
3598 		count += j;
3599 		for (; j > 0; j--)
3600 			ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3601 	}
3602 	if (!count)
3603 		return 0;
3604 	return EXT4_CLUSTERS_PER_GROUP(sb) -
3605 		ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3606 }
3607 
3608 /*
3609  * Compute the overhead and stash it in sbi->s_overhead
3610  */
3611 int ext4_calculate_overhead(struct super_block *sb)
3612 {
3613 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3614 	struct ext4_super_block *es = sbi->s_es;
3615 	struct inode *j_inode;
3616 	unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3617 	ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3618 	ext4_fsblk_t overhead = 0;
3619 	char *buf = (char *) get_zeroed_page(GFP_NOFS);
3620 
3621 	if (!buf)
3622 		return -ENOMEM;
3623 
3624 	/*
3625 	 * Compute the overhead (FS structures).  This is constant
3626 	 * for a given filesystem unless the number of block groups
3627 	 * changes so we cache the previous value until it does.
3628 	 */
3629 
3630 	/*
3631 	 * All of the blocks before first_data_block are overhead
3632 	 */
3633 	overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3634 
3635 	/*
3636 	 * Add the overhead found in each block group
3637 	 */
3638 	for (i = 0; i < ngroups; i++) {
3639 		int blks;
3640 
3641 		blks = count_overhead(sb, i, buf);
3642 		overhead += blks;
3643 		if (blks)
3644 			memset(buf, 0, PAGE_SIZE);
3645 		cond_resched();
3646 	}
3647 
3648 	/*
3649 	 * Add the internal journal blocks whether the journal has been
3650 	 * loaded or not
3651 	 */
3652 	if (sbi->s_journal && !sbi->journal_bdev)
3653 		overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3654 	else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3655 		/* j_inum for internal journal is non-zero */
3656 		j_inode = ext4_get_journal_inode(sb, j_inum);
3657 		if (j_inode) {
3658 			j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3659 			overhead += EXT4_NUM_B2C(sbi, j_blocks);
3660 			iput(j_inode);
3661 		} else {
3662 			ext4_msg(sb, KERN_ERR, "can't get journal size");
3663 		}
3664 	}
3665 	sbi->s_overhead = overhead;
3666 	smp_wmb();
3667 	free_page((unsigned long) buf);
3668 	return 0;
3669 }
3670 
3671 static void ext4_set_resv_clusters(struct super_block *sb)
3672 {
3673 	ext4_fsblk_t resv_clusters;
3674 	struct ext4_sb_info *sbi = EXT4_SB(sb);
3675 
3676 	/*
3677 	 * There's no need to reserve anything when we aren't using extents.
3678 	 * The space estimates are exact, there are no unwritten extents,
3679 	 * hole punching doesn't need new metadata... This is needed especially
3680 	 * to keep ext2/3 backward compatibility.
3681 	 */
3682 	if (!ext4_has_feature_extents(sb))
3683 		return;
3684 	/*
3685 	 * By default we reserve 2% or 4096 clusters, whichever is smaller.
3686 	 * This should cover the situations where we can not afford to run
3687 	 * out of space like for example punch hole, or converting
3688 	 * unwritten extents in delalloc path. In most cases such
3689 	 * allocation would require 1, or 2 blocks, higher numbers are
3690 	 * very rare.
3691 	 */
3692 	resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3693 			 sbi->s_cluster_bits);
3694 
3695 	do_div(resv_clusters, 50);
3696 	resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3697 
3698 	atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3699 }
3700 
3701 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3702 {
3703 	struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3704 	char *orig_data = kstrdup(data, GFP_KERNEL);
3705 	struct buffer_head *bh, **group_desc;
3706 	struct ext4_super_block *es = NULL;
3707 	struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3708 	struct flex_groups **flex_groups;
3709 	ext4_fsblk_t block;
3710 	ext4_fsblk_t sb_block = get_sb_block(&data);
3711 	ext4_fsblk_t logical_sb_block;
3712 	unsigned long offset = 0;
3713 	unsigned long journal_devnum = 0;
3714 	unsigned long def_mount_opts;
3715 	struct inode *root;
3716 	const char *descr;
3717 	int ret = -ENOMEM;
3718 	int blocksize, clustersize;
3719 	unsigned int db_count;
3720 	unsigned int i;
3721 	int needs_recovery, has_huge_files;
3722 	__u64 blocks_count;
3723 	int err = 0;
3724 	unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3725 	ext4_group_t first_not_zeroed;
3726 
3727 	if ((data && !orig_data) || !sbi)
3728 		goto out_free_base;
3729 
3730 	sbi->s_daxdev = dax_dev;
3731 	sbi->s_blockgroup_lock =
3732 		kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3733 	if (!sbi->s_blockgroup_lock)
3734 		goto out_free_base;
3735 
3736 	sb->s_fs_info = sbi;
3737 	sbi->s_sb = sb;
3738 	sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3739 	sbi->s_sb_block = sb_block;
3740 	if (sb->s_bdev->bd_part)
3741 		sbi->s_sectors_written_start =
3742 			part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3743 
3744 	/* Cleanup superblock name */
3745 	strreplace(sb->s_id, '/', '!');
3746 
3747 	/* -EINVAL is default */
3748 	ret = -EINVAL;
3749 	blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3750 	if (!blocksize) {
3751 		ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3752 		goto out_fail;
3753 	}
3754 
3755 	/*
3756 	 * The ext4 superblock will not be buffer aligned for other than 1kB
3757 	 * block sizes.  We need to calculate the offset from buffer start.
3758 	 */
3759 	if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3760 		logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3761 		offset = do_div(logical_sb_block, blocksize);
3762 	} else {
3763 		logical_sb_block = sb_block;
3764 	}
3765 
3766 	if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3767 		ext4_msg(sb, KERN_ERR, "unable to read superblock");
3768 		goto out_fail;
3769 	}
3770 	/*
3771 	 * Note: s_es must be initialized as soon as possible because
3772 	 *       some ext4 macro-instructions depend on its value
3773 	 */
3774 	es = (struct ext4_super_block *) (bh->b_data + offset);
3775 	sbi->s_es = es;
3776 	sb->s_magic = le16_to_cpu(es->s_magic);
3777 	if (sb->s_magic != EXT4_SUPER_MAGIC)
3778 		goto cantfind_ext4;
3779 	sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3780 
3781 	/* Warn if metadata_csum and gdt_csum are both set. */
3782 	if (ext4_has_feature_metadata_csum(sb) &&
3783 	    ext4_has_feature_gdt_csum(sb))
3784 		ext4_warning(sb, "metadata_csum and uninit_bg are "
3785 			     "redundant flags; please run fsck.");
3786 
3787 	/* Check for a known checksum algorithm */
3788 	if (!ext4_verify_csum_type(sb, es)) {
3789 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3790 			 "unknown checksum algorithm.");
3791 		silent = 1;
3792 		goto cantfind_ext4;
3793 	}
3794 
3795 	/* Load the checksum driver */
3796 	sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3797 	if (IS_ERR(sbi->s_chksum_driver)) {
3798 		ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3799 		ret = PTR_ERR(sbi->s_chksum_driver);
3800 		sbi->s_chksum_driver = NULL;
3801 		goto failed_mount;
3802 	}
3803 
3804 	/* Check superblock checksum */
3805 	if (!ext4_superblock_csum_verify(sb, es)) {
3806 		ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3807 			 "invalid superblock checksum.  Run e2fsck?");
3808 		silent = 1;
3809 		ret = -EFSBADCRC;
3810 		goto cantfind_ext4;
3811 	}
3812 
3813 	/* Precompute checksum seed for all metadata */
3814 	if (ext4_has_feature_csum_seed(sb))
3815 		sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3816 	else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3817 		sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3818 					       sizeof(es->s_uuid));
3819 
3820 	/* Set defaults before we parse the mount options */
3821 	def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3822 	set_opt(sb, INIT_INODE_TABLE);
3823 	if (def_mount_opts & EXT4_DEFM_DEBUG)
3824 		set_opt(sb, DEBUG);
3825 	if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3826 		set_opt(sb, GRPID);
3827 	if (def_mount_opts & EXT4_DEFM_UID16)
3828 		set_opt(sb, NO_UID32);
3829 	/* xattr user namespace & acls are now defaulted on */
3830 	set_opt(sb, XATTR_USER);
3831 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3832 	set_opt(sb, POSIX_ACL);
3833 #endif
3834 	/* don't forget to enable journal_csum when metadata_csum is enabled. */
3835 	if (ext4_has_metadata_csum(sb))
3836 		set_opt(sb, JOURNAL_CHECKSUM);
3837 
3838 	if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3839 		set_opt(sb, JOURNAL_DATA);
3840 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3841 		set_opt(sb, ORDERED_DATA);
3842 	else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3843 		set_opt(sb, WRITEBACK_DATA);
3844 
3845 	if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3846 		set_opt(sb, ERRORS_PANIC);
3847 	else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3848 		set_opt(sb, ERRORS_CONT);
3849 	else
3850 		set_opt(sb, ERRORS_RO);
3851 	/* block_validity enabled by default; disable with noblock_validity */
3852 	set_opt(sb, BLOCK_VALIDITY);
3853 	if (def_mount_opts & EXT4_DEFM_DISCARD)
3854 		set_opt(sb, DISCARD);
3855 
3856 	sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3857 	sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3858 	sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3859 	sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3860 	sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3861 
3862 	if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3863 		set_opt(sb, BARRIER);
3864 
3865 	/*
3866 	 * enable delayed allocation by default
3867 	 * Use -o nodelalloc to turn it off
3868 	 */
3869 	if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3870 	    ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3871 		set_opt(sb, DELALLOC);
3872 
3873 	/*
3874 	 * set default s_li_wait_mult for lazyinit, for the case there is
3875 	 * no mount option specified.
3876 	 */
3877 	sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3878 
3879 	blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3880 
3881 	if (blocksize == PAGE_SIZE)
3882 		set_opt(sb, DIOREAD_NOLOCK);
3883 
3884 	if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3885 	    blocksize > EXT4_MAX_BLOCK_SIZE) {
3886 		ext4_msg(sb, KERN_ERR,
3887 		       "Unsupported filesystem blocksize %d (%d log_block_size)",
3888 			 blocksize, le32_to_cpu(es->s_log_block_size));
3889 		goto failed_mount;
3890 	}
3891 
3892 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3893 		sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3894 		sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3895 	} else {
3896 		sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3897 		sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3898 		if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3899 			ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3900 				 sbi->s_first_ino);
3901 			goto failed_mount;
3902 		}
3903 		if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3904 		    (!is_power_of_2(sbi->s_inode_size)) ||
3905 		    (sbi->s_inode_size > blocksize)) {
3906 			ext4_msg(sb, KERN_ERR,
3907 			       "unsupported inode size: %d",
3908 			       sbi->s_inode_size);
3909 			ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
3910 			goto failed_mount;
3911 		}
3912 		/*
3913 		 * i_atime_extra is the last extra field available for
3914 		 * [acm]times in struct ext4_inode. Checking for that
3915 		 * field should suffice to ensure we have extra space
3916 		 * for all three.
3917 		 */
3918 		if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
3919 			sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
3920 			sb->s_time_gran = 1;
3921 			sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
3922 		} else {
3923 			sb->s_time_gran = NSEC_PER_SEC;
3924 			sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
3925 		}
3926 		sb->s_time_min = EXT4_TIMESTAMP_MIN;
3927 	}
3928 	if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3929 		sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3930 			EXT4_GOOD_OLD_INODE_SIZE;
3931 		if (ext4_has_feature_extra_isize(sb)) {
3932 			unsigned v, max = (sbi->s_inode_size -
3933 					   EXT4_GOOD_OLD_INODE_SIZE);
3934 
3935 			v = le16_to_cpu(es->s_want_extra_isize);
3936 			if (v > max) {
3937 				ext4_msg(sb, KERN_ERR,
3938 					 "bad s_want_extra_isize: %d", v);
3939 				goto failed_mount;
3940 			}
3941 			if (sbi->s_want_extra_isize < v)
3942 				sbi->s_want_extra_isize = v;
3943 
3944 			v = le16_to_cpu(es->s_min_extra_isize);
3945 			if (v > max) {
3946 				ext4_msg(sb, KERN_ERR,
3947 					 "bad s_min_extra_isize: %d", v);
3948 				goto failed_mount;
3949 			}
3950 			if (sbi->s_want_extra_isize < v)
3951 				sbi->s_want_extra_isize = v;
3952 		}
3953 	}
3954 
3955 	if (sbi->s_es->s_mount_opts[0]) {
3956 		char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3957 					      sizeof(sbi->s_es->s_mount_opts),
3958 					      GFP_KERNEL);
3959 		if (!s_mount_opts)
3960 			goto failed_mount;
3961 		if (!parse_options(s_mount_opts, sb, &journal_devnum,
3962 				   &journal_ioprio, 0)) {
3963 			ext4_msg(sb, KERN_WARNING,
3964 				 "failed to parse options in superblock: %s",
3965 				 s_mount_opts);
3966 		}
3967 		kfree(s_mount_opts);
3968 	}
3969 	sbi->s_def_mount_opt = sbi->s_mount_opt;
3970 	if (!parse_options((char *) data, sb, &journal_devnum,
3971 			   &journal_ioprio, 0))
3972 		goto failed_mount;
3973 
3974 #ifdef CONFIG_UNICODE
3975 	if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
3976 		const struct ext4_sb_encodings *encoding_info;
3977 		struct unicode_map *encoding;
3978 		__u16 encoding_flags;
3979 
3980 		if (ext4_has_feature_encrypt(sb)) {
3981 			ext4_msg(sb, KERN_ERR,
3982 				 "Can't mount with encoding and encryption");
3983 			goto failed_mount;
3984 		}
3985 
3986 		if (ext4_sb_read_encoding(es, &encoding_info,
3987 					  &encoding_flags)) {
3988 			ext4_msg(sb, KERN_ERR,
3989 				 "Encoding requested by superblock is unknown");
3990 			goto failed_mount;
3991 		}
3992 
3993 		encoding = utf8_load(encoding_info->version);
3994 		if (IS_ERR(encoding)) {
3995 			ext4_msg(sb, KERN_ERR,
3996 				 "can't mount with superblock charset: %s-%s "
3997 				 "not supported by the kernel. flags: 0x%x.",
3998 				 encoding_info->name, encoding_info->version,
3999 				 encoding_flags);
4000 			goto failed_mount;
4001 		}
4002 		ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4003 			 "%s-%s with flags 0x%hx", encoding_info->name,
4004 			 encoding_info->version?:"\b", encoding_flags);
4005 
4006 		sbi->s_encoding = encoding;
4007 		sbi->s_encoding_flags = encoding_flags;
4008 	}
4009 #endif
4010 
4011 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4012 		printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, and O_DIRECT support!\n");
4013 		/* can't mount with both data=journal and dioread_nolock. */
4014 		clear_opt(sb, DIOREAD_NOLOCK);
4015 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4016 			ext4_msg(sb, KERN_ERR, "can't mount with "
4017 				 "both data=journal and delalloc");
4018 			goto failed_mount;
4019 		}
4020 		if (test_opt(sb, DAX)) {
4021 			ext4_msg(sb, KERN_ERR, "can't mount with "
4022 				 "both data=journal and dax");
4023 			goto failed_mount;
4024 		}
4025 		if (ext4_has_feature_encrypt(sb)) {
4026 			ext4_msg(sb, KERN_WARNING,
4027 				 "encrypted files will use data=ordered "
4028 				 "instead of data journaling mode");
4029 		}
4030 		if (test_opt(sb, DELALLOC))
4031 			clear_opt(sb, DELALLOC);
4032 	} else {
4033 		sb->s_iflags |= SB_I_CGROUPWB;
4034 	}
4035 
4036 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4037 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4038 
4039 	if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4040 	    (ext4_has_compat_features(sb) ||
4041 	     ext4_has_ro_compat_features(sb) ||
4042 	     ext4_has_incompat_features(sb)))
4043 		ext4_msg(sb, KERN_WARNING,
4044 		       "feature flags set on rev 0 fs, "
4045 		       "running e2fsck is recommended");
4046 
4047 	if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4048 		set_opt2(sb, HURD_COMPAT);
4049 		if (ext4_has_feature_64bit(sb)) {
4050 			ext4_msg(sb, KERN_ERR,
4051 				 "The Hurd can't support 64-bit file systems");
4052 			goto failed_mount;
4053 		}
4054 
4055 		/*
4056 		 * ea_inode feature uses l_i_version field which is not
4057 		 * available in HURD_COMPAT mode.
4058 		 */
4059 		if (ext4_has_feature_ea_inode(sb)) {
4060 			ext4_msg(sb, KERN_ERR,
4061 				 "ea_inode feature is not supported for Hurd");
4062 			goto failed_mount;
4063 		}
4064 	}
4065 
4066 	if (IS_EXT2_SB(sb)) {
4067 		if (ext2_feature_set_ok(sb))
4068 			ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4069 				 "using the ext4 subsystem");
4070 		else {
4071 			/*
4072 			 * If we're probing be silent, if this looks like
4073 			 * it's actually an ext[34] filesystem.
4074 			 */
4075 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4076 				goto failed_mount;
4077 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4078 				 "to feature incompatibilities");
4079 			goto failed_mount;
4080 		}
4081 	}
4082 
4083 	if (IS_EXT3_SB(sb)) {
4084 		if (ext3_feature_set_ok(sb))
4085 			ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4086 				 "using the ext4 subsystem");
4087 		else {
4088 			/*
4089 			 * If we're probing be silent, if this looks like
4090 			 * it's actually an ext4 filesystem.
4091 			 */
4092 			if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4093 				goto failed_mount;
4094 			ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4095 				 "to feature incompatibilities");
4096 			goto failed_mount;
4097 		}
4098 	}
4099 
4100 	/*
4101 	 * Check feature flags regardless of the revision level, since we
4102 	 * previously didn't change the revision level when setting the flags,
4103 	 * so there is a chance incompat flags are set on a rev 0 filesystem.
4104 	 */
4105 	if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4106 		goto failed_mount;
4107 
4108 	if (le32_to_cpu(es->s_log_block_size) >
4109 	    (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4110 		ext4_msg(sb, KERN_ERR,
4111 			 "Invalid log block size: %u",
4112 			 le32_to_cpu(es->s_log_block_size));
4113 		goto failed_mount;
4114 	}
4115 	if (le32_to_cpu(es->s_log_cluster_size) >
4116 	    (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4117 		ext4_msg(sb, KERN_ERR,
4118 			 "Invalid log cluster size: %u",
4119 			 le32_to_cpu(es->s_log_cluster_size));
4120 		goto failed_mount;
4121 	}
4122 
4123 	if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4124 		ext4_msg(sb, KERN_ERR,
4125 			 "Number of reserved GDT blocks insanely large: %d",
4126 			 le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4127 		goto failed_mount;
4128 	}
4129 
4130 	if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
4131 		if (ext4_has_feature_inline_data(sb)) {
4132 			ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4133 					" that may contain inline data");
4134 			goto failed_mount;
4135 		}
4136 		if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
4137 			ext4_msg(sb, KERN_ERR,
4138 				"DAX unsupported by block device.");
4139 			goto failed_mount;
4140 		}
4141 	}
4142 
4143 	if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4144 		ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4145 			 es->s_encryption_level);
4146 		goto failed_mount;
4147 	}
4148 
4149 	if (sb->s_blocksize != blocksize) {
4150 		/* Validate the filesystem blocksize */
4151 		if (!sb_set_blocksize(sb, blocksize)) {
4152 			ext4_msg(sb, KERN_ERR, "bad block size %d",
4153 					blocksize);
4154 			goto failed_mount;
4155 		}
4156 
4157 		brelse(bh);
4158 		logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4159 		offset = do_div(logical_sb_block, blocksize);
4160 		bh = sb_bread_unmovable(sb, logical_sb_block);
4161 		if (!bh) {
4162 			ext4_msg(sb, KERN_ERR,
4163 			       "Can't read superblock on 2nd try");
4164 			goto failed_mount;
4165 		}
4166 		es = (struct ext4_super_block *)(bh->b_data + offset);
4167 		sbi->s_es = es;
4168 		if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4169 			ext4_msg(sb, KERN_ERR,
4170 			       "Magic mismatch, very weird!");
4171 			goto failed_mount;
4172 		}
4173 	}
4174 
4175 	has_huge_files = ext4_has_feature_huge_file(sb);
4176 	sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4177 						      has_huge_files);
4178 	sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4179 
4180 	sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4181 	if (ext4_has_feature_64bit(sb)) {
4182 		if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4183 		    sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4184 		    !is_power_of_2(sbi->s_desc_size)) {
4185 			ext4_msg(sb, KERN_ERR,
4186 			       "unsupported descriptor size %lu",
4187 			       sbi->s_desc_size);
4188 			goto failed_mount;
4189 		}
4190 	} else
4191 		sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4192 
4193 	sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4194 	sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4195 
4196 	sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4197 	if (sbi->s_inodes_per_block == 0)
4198 		goto cantfind_ext4;
4199 	if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4200 	    sbi->s_inodes_per_group > blocksize * 8) {
4201 		ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4202 			 sbi->s_inodes_per_group);
4203 		goto failed_mount;
4204 	}
4205 	sbi->s_itb_per_group = sbi->s_inodes_per_group /
4206 					sbi->s_inodes_per_block;
4207 	sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4208 	sbi->s_sbh = bh;
4209 	sbi->s_mount_state = le16_to_cpu(es->s_state);
4210 	sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4211 	sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4212 
4213 	for (i = 0; i < 4; i++)
4214 		sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4215 	sbi->s_def_hash_version = es->s_def_hash_version;
4216 	if (ext4_has_feature_dir_index(sb)) {
4217 		i = le32_to_cpu(es->s_flags);
4218 		if (i & EXT2_FLAGS_UNSIGNED_HASH)
4219 			sbi->s_hash_unsigned = 3;
4220 		else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4221 #ifdef __CHAR_UNSIGNED__
4222 			if (!sb_rdonly(sb))
4223 				es->s_flags |=
4224 					cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4225 			sbi->s_hash_unsigned = 3;
4226 #else
4227 			if (!sb_rdonly(sb))
4228 				es->s_flags |=
4229 					cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4230 #endif
4231 		}
4232 	}
4233 
4234 	/* Handle clustersize */
4235 	clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4236 	if (ext4_has_feature_bigalloc(sb)) {
4237 		if (clustersize < blocksize) {
4238 			ext4_msg(sb, KERN_ERR,
4239 				 "cluster size (%d) smaller than "
4240 				 "block size (%d)", clustersize, blocksize);
4241 			goto failed_mount;
4242 		}
4243 		sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4244 			le32_to_cpu(es->s_log_block_size);
4245 		sbi->s_clusters_per_group =
4246 			le32_to_cpu(es->s_clusters_per_group);
4247 		if (sbi->s_clusters_per_group > blocksize * 8) {
4248 			ext4_msg(sb, KERN_ERR,
4249 				 "#clusters per group too big: %lu",
4250 				 sbi->s_clusters_per_group);
4251 			goto failed_mount;
4252 		}
4253 		if (sbi->s_blocks_per_group !=
4254 		    (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4255 			ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4256 				 "clusters per group (%lu) inconsistent",
4257 				 sbi->s_blocks_per_group,
4258 				 sbi->s_clusters_per_group);
4259 			goto failed_mount;
4260 		}
4261 	} else {
4262 		if (clustersize != blocksize) {
4263 			ext4_msg(sb, KERN_ERR,
4264 				 "fragment/cluster size (%d) != "
4265 				 "block size (%d)", clustersize, blocksize);
4266 			goto failed_mount;
4267 		}
4268 		if (sbi->s_blocks_per_group > blocksize * 8) {
4269 			ext4_msg(sb, KERN_ERR,
4270 				 "#blocks per group too big: %lu",
4271 				 sbi->s_blocks_per_group);
4272 			goto failed_mount;
4273 		}
4274 		sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4275 		sbi->s_cluster_bits = 0;
4276 	}
4277 	sbi->s_cluster_ratio = clustersize / blocksize;
4278 
4279 	/* Do we have standard group size of clustersize * 8 blocks ? */
4280 	if (sbi->s_blocks_per_group == clustersize << 3)
4281 		set_opt2(sb, STD_GROUP_SIZE);
4282 
4283 	/*
4284 	 * Test whether we have more sectors than will fit in sector_t,
4285 	 * and whether the max offset is addressable by the page cache.
4286 	 */
4287 	err = generic_check_addressable(sb->s_blocksize_bits,
4288 					ext4_blocks_count(es));
4289 	if (err) {
4290 		ext4_msg(sb, KERN_ERR, "filesystem"
4291 			 " too large to mount safely on this system");
4292 		goto failed_mount;
4293 	}
4294 
4295 	if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4296 		goto cantfind_ext4;
4297 
4298 	/* check blocks count against device size */
4299 	blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4300 	if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4301 		ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4302 		       "exceeds size of device (%llu blocks)",
4303 		       ext4_blocks_count(es), blocks_count);
4304 		goto failed_mount;
4305 	}
4306 
4307 	/*
4308 	 * It makes no sense for the first data block to be beyond the end
4309 	 * of the filesystem.
4310 	 */
4311 	if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4312 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4313 			 "block %u is beyond end of filesystem (%llu)",
4314 			 le32_to_cpu(es->s_first_data_block),
4315 			 ext4_blocks_count(es));
4316 		goto failed_mount;
4317 	}
4318 	if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4319 	    (sbi->s_cluster_ratio == 1)) {
4320 		ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4321 			 "block is 0 with a 1k block and cluster size");
4322 		goto failed_mount;
4323 	}
4324 
4325 	blocks_count = (ext4_blocks_count(es) -
4326 			le32_to_cpu(es->s_first_data_block) +
4327 			EXT4_BLOCKS_PER_GROUP(sb) - 1);
4328 	do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4329 	if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4330 		ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4331 		       "(block count %llu, first data block %u, "
4332 		       "blocks per group %lu)", blocks_count,
4333 		       ext4_blocks_count(es),
4334 		       le32_to_cpu(es->s_first_data_block),
4335 		       EXT4_BLOCKS_PER_GROUP(sb));
4336 		goto failed_mount;
4337 	}
4338 	sbi->s_groups_count = blocks_count;
4339 	sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4340 			(EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4341 	if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4342 	    le32_to_cpu(es->s_inodes_count)) {
4343 		ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4344 			 le32_to_cpu(es->s_inodes_count),
4345 			 ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4346 		ret = -EINVAL;
4347 		goto failed_mount;
4348 	}
4349 	db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4350 		   EXT4_DESC_PER_BLOCK(sb);
4351 	if (ext4_has_feature_meta_bg(sb)) {
4352 		if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4353 			ext4_msg(sb, KERN_WARNING,
4354 				 "first meta block group too large: %u "
4355 				 "(group descriptor block count %u)",
4356 				 le32_to_cpu(es->s_first_meta_bg), db_count);
4357 			goto failed_mount;
4358 		}
4359 	}
4360 	rcu_assign_pointer(sbi->s_group_desc,
4361 			   kvmalloc_array(db_count,
4362 					  sizeof(struct buffer_head *),
4363 					  GFP_KERNEL));
4364 	if (sbi->s_group_desc == NULL) {
4365 		ext4_msg(sb, KERN_ERR, "not enough memory");
4366 		ret = -ENOMEM;
4367 		goto failed_mount;
4368 	}
4369 
4370 	bgl_lock_init(sbi->s_blockgroup_lock);
4371 
4372 	/* Pre-read the descriptors into the buffer cache */
4373 	for (i = 0; i < db_count; i++) {
4374 		block = descriptor_loc(sb, logical_sb_block, i);
4375 		sb_breadahead_unmovable(sb, block);
4376 	}
4377 
4378 	for (i = 0; i < db_count; i++) {
4379 		struct buffer_head *bh;
4380 
4381 		block = descriptor_loc(sb, logical_sb_block, i);
4382 		bh = sb_bread_unmovable(sb, block);
4383 		if (!bh) {
4384 			ext4_msg(sb, KERN_ERR,
4385 			       "can't read group descriptor %d", i);
4386 			db_count = i;
4387 			goto failed_mount2;
4388 		}
4389 		rcu_read_lock();
4390 		rcu_dereference(sbi->s_group_desc)[i] = bh;
4391 		rcu_read_unlock();
4392 	}
4393 	sbi->s_gdb_count = db_count;
4394 	if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4395 		ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4396 		ret = -EFSCORRUPTED;
4397 		goto failed_mount2;
4398 	}
4399 
4400 	timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4401 
4402 	/* Register extent status tree shrinker */
4403 	if (ext4_es_register_shrinker(sbi))
4404 		goto failed_mount3;
4405 
4406 	sbi->s_stripe = ext4_get_stripe_size(sbi);
4407 	sbi->s_extent_max_zeroout_kb = 32;
4408 
4409 	/*
4410 	 * set up enough so that it can read an inode
4411 	 */
4412 	sb->s_op = &ext4_sops;
4413 	sb->s_export_op = &ext4_export_ops;
4414 	sb->s_xattr = ext4_xattr_handlers;
4415 #ifdef CONFIG_FS_ENCRYPTION
4416 	sb->s_cop = &ext4_cryptops;
4417 #endif
4418 #ifdef CONFIG_FS_VERITY
4419 	sb->s_vop = &ext4_verityops;
4420 #endif
4421 #ifdef CONFIG_QUOTA
4422 	sb->dq_op = &ext4_quota_operations;
4423 	if (ext4_has_feature_quota(sb))
4424 		sb->s_qcop = &dquot_quotactl_sysfile_ops;
4425 	else
4426 		sb->s_qcop = &ext4_qctl_operations;
4427 	sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4428 #endif
4429 	memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4430 
4431 	INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4432 	mutex_init(&sbi->s_orphan_lock);
4433 
4434 	sb->s_root = NULL;
4435 
4436 	needs_recovery = (es->s_last_orphan != 0 ||
4437 			  ext4_has_feature_journal_needs_recovery(sb));
4438 
4439 	if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4440 		if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4441 			goto failed_mount3a;
4442 
4443 	/*
4444 	 * The first inode we look at is the journal inode.  Don't try
4445 	 * root first: it may be modified in the journal!
4446 	 */
4447 	if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4448 		err = ext4_load_journal(sb, es, journal_devnum);
4449 		if (err)
4450 			goto failed_mount3a;
4451 	} else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4452 		   ext4_has_feature_journal_needs_recovery(sb)) {
4453 		ext4_msg(sb, KERN_ERR, "required journal recovery "
4454 		       "suppressed and not mounted read-only");
4455 		goto failed_mount_wq;
4456 	} else {
4457 		/* Nojournal mode, all journal mount options are illegal */
4458 		if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4459 			ext4_msg(sb, KERN_ERR, "can't mount with "
4460 				 "journal_checksum, fs mounted w/o journal");
4461 			goto failed_mount_wq;
4462 		}
4463 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4464 			ext4_msg(sb, KERN_ERR, "can't mount with "
4465 				 "journal_async_commit, fs mounted w/o journal");
4466 			goto failed_mount_wq;
4467 		}
4468 		if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4469 			ext4_msg(sb, KERN_ERR, "can't mount with "
4470 				 "commit=%lu, fs mounted w/o journal",
4471 				 sbi->s_commit_interval / HZ);
4472 			goto failed_mount_wq;
4473 		}
4474 		if (EXT4_MOUNT_DATA_FLAGS &
4475 		    (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4476 			ext4_msg(sb, KERN_ERR, "can't mount with "
4477 				 "data=, fs mounted w/o journal");
4478 			goto failed_mount_wq;
4479 		}
4480 		sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4481 		clear_opt(sb, JOURNAL_CHECKSUM);
4482 		clear_opt(sb, DATA_FLAGS);
4483 		sbi->s_journal = NULL;
4484 		needs_recovery = 0;
4485 		goto no_journal;
4486 	}
4487 
4488 	if (ext4_has_feature_64bit(sb) &&
4489 	    !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4490 				       JBD2_FEATURE_INCOMPAT_64BIT)) {
4491 		ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4492 		goto failed_mount_wq;
4493 	}
4494 
4495 	if (!set_journal_csum_feature_set(sb)) {
4496 		ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4497 			 "feature set");
4498 		goto failed_mount_wq;
4499 	}
4500 
4501 	/* We have now updated the journal if required, so we can
4502 	 * validate the data journaling mode. */
4503 	switch (test_opt(sb, DATA_FLAGS)) {
4504 	case 0:
4505 		/* No mode set, assume a default based on the journal
4506 		 * capabilities: ORDERED_DATA if the journal can
4507 		 * cope, else JOURNAL_DATA
4508 		 */
4509 		if (jbd2_journal_check_available_features
4510 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4511 			set_opt(sb, ORDERED_DATA);
4512 			sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4513 		} else {
4514 			set_opt(sb, JOURNAL_DATA);
4515 			sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4516 		}
4517 		break;
4518 
4519 	case EXT4_MOUNT_ORDERED_DATA:
4520 	case EXT4_MOUNT_WRITEBACK_DATA:
4521 		if (!jbd2_journal_check_available_features
4522 		    (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4523 			ext4_msg(sb, KERN_ERR, "Journal does not support "
4524 			       "requested data journaling mode");
4525 			goto failed_mount_wq;
4526 		}
4527 	default:
4528 		break;
4529 	}
4530 
4531 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4532 	    test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4533 		ext4_msg(sb, KERN_ERR, "can't mount with "
4534 			"journal_async_commit in data=ordered mode");
4535 		goto failed_mount_wq;
4536 	}
4537 
4538 	set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4539 
4540 	sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4541 
4542 no_journal:
4543 	if (!test_opt(sb, NO_MBCACHE)) {
4544 		sbi->s_ea_block_cache = ext4_xattr_create_cache();
4545 		if (!sbi->s_ea_block_cache) {
4546 			ext4_msg(sb, KERN_ERR,
4547 				 "Failed to create ea_block_cache");
4548 			goto failed_mount_wq;
4549 		}
4550 
4551 		if (ext4_has_feature_ea_inode(sb)) {
4552 			sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4553 			if (!sbi->s_ea_inode_cache) {
4554 				ext4_msg(sb, KERN_ERR,
4555 					 "Failed to create ea_inode_cache");
4556 				goto failed_mount_wq;
4557 			}
4558 		}
4559 	}
4560 
4561 	if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4562 		ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4563 		goto failed_mount_wq;
4564 	}
4565 
4566 	if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4567 	    !ext4_has_feature_encrypt(sb)) {
4568 		ext4_set_feature_encrypt(sb);
4569 		ext4_commit_super(sb, 1);
4570 	}
4571 
4572 	/*
4573 	 * Get the # of file system overhead blocks from the
4574 	 * superblock if present.
4575 	 */
4576 	if (es->s_overhead_clusters)
4577 		sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4578 	else {
4579 		err = ext4_calculate_overhead(sb);
4580 		if (err)
4581 			goto failed_mount_wq;
4582 	}
4583 
4584 	/*
4585 	 * The maximum number of concurrent works can be high and
4586 	 * concurrency isn't really necessary.  Limit it to 1.
4587 	 */
4588 	EXT4_SB(sb)->rsv_conversion_wq =
4589 		alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4590 	if (!EXT4_SB(sb)->rsv_conversion_wq) {
4591 		printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4592 		ret = -ENOMEM;
4593 		goto failed_mount4;
4594 	}
4595 
4596 	/*
4597 	 * The jbd2_journal_load will have done any necessary log recovery,
4598 	 * so we can safely mount the rest of the filesystem now.
4599 	 */
4600 
4601 	root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4602 	if (IS_ERR(root)) {
4603 		ext4_msg(sb, KERN_ERR, "get root inode failed");
4604 		ret = PTR_ERR(root);
4605 		root = NULL;
4606 		goto failed_mount4;
4607 	}
4608 	if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4609 		ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4610 		iput(root);
4611 		goto failed_mount4;
4612 	}
4613 
4614 #ifdef CONFIG_UNICODE
4615 	if (sbi->s_encoding)
4616 		sb->s_d_op = &ext4_dentry_ops;
4617 #endif
4618 
4619 	sb->s_root = d_make_root(root);
4620 	if (!sb->s_root) {
4621 		ext4_msg(sb, KERN_ERR, "get root dentry failed");
4622 		ret = -ENOMEM;
4623 		goto failed_mount4;
4624 	}
4625 
4626 	ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4627 	if (ret == -EROFS) {
4628 		sb->s_flags |= SB_RDONLY;
4629 		ret = 0;
4630 	} else if (ret)
4631 		goto failed_mount4a;
4632 
4633 	ext4_set_resv_clusters(sb);
4634 
4635 	err = ext4_setup_system_zone(sb);
4636 	if (err) {
4637 		ext4_msg(sb, KERN_ERR, "failed to initialize system "
4638 			 "zone (%d)", err);
4639 		goto failed_mount4a;
4640 	}
4641 
4642 	ext4_ext_init(sb);
4643 	err = ext4_mb_init(sb);
4644 	if (err) {
4645 		ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4646 			 err);
4647 		goto failed_mount5;
4648 	}
4649 
4650 	block = ext4_count_free_clusters(sb);
4651 	ext4_free_blocks_count_set(sbi->s_es,
4652 				   EXT4_C2B(sbi, block));
4653 	ext4_superblock_csum_set(sb);
4654 	err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4655 				  GFP_KERNEL);
4656 	if (!err) {
4657 		unsigned long freei = ext4_count_free_inodes(sb);
4658 		sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4659 		ext4_superblock_csum_set(sb);
4660 		err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4661 					  GFP_KERNEL);
4662 	}
4663 	if (!err)
4664 		err = percpu_counter_init(&sbi->s_dirs_counter,
4665 					  ext4_count_dirs(sb), GFP_KERNEL);
4666 	if (!err)
4667 		err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4668 					  GFP_KERNEL);
4669 	if (!err)
4670 		err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4671 
4672 	if (err) {
4673 		ext4_msg(sb, KERN_ERR, "insufficient memory");
4674 		goto failed_mount6;
4675 	}
4676 
4677 	if (ext4_has_feature_flex_bg(sb))
4678 		if (!ext4_fill_flex_info(sb)) {
4679 			ext4_msg(sb, KERN_ERR,
4680 			       "unable to initialize "
4681 			       "flex_bg meta info!");
4682 			goto failed_mount6;
4683 		}
4684 
4685 	err = ext4_register_li_request(sb, first_not_zeroed);
4686 	if (err)
4687 		goto failed_mount6;
4688 
4689 	err = ext4_register_sysfs(sb);
4690 	if (err)
4691 		goto failed_mount7;
4692 
4693 #ifdef CONFIG_QUOTA
4694 	/* Enable quota usage during mount. */
4695 	if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4696 		err = ext4_enable_quotas(sb);
4697 		if (err)
4698 			goto failed_mount8;
4699 	}
4700 #endif  /* CONFIG_QUOTA */
4701 
4702 	EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4703 	ext4_orphan_cleanup(sb, es);
4704 	EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4705 	if (needs_recovery) {
4706 		ext4_msg(sb, KERN_INFO, "recovery complete");
4707 		ext4_mark_recovery_complete(sb, es);
4708 	}
4709 	if (EXT4_SB(sb)->s_journal) {
4710 		if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4711 			descr = " journalled data mode";
4712 		else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4713 			descr = " ordered data mode";
4714 		else
4715 			descr = " writeback data mode";
4716 	} else
4717 		descr = "out journal";
4718 
4719 	if (test_opt(sb, DISCARD)) {
4720 		struct request_queue *q = bdev_get_queue(sb->s_bdev);
4721 		if (!blk_queue_discard(q))
4722 			ext4_msg(sb, KERN_WARNING,
4723 				 "mounting with \"discard\" option, but "
4724 				 "the device does not support discard");
4725 	}
4726 
4727 	if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4728 		ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4729 			 "Opts: %.*s%s%s", descr,
4730 			 (int) sizeof(sbi->s_es->s_mount_opts),
4731 			 sbi->s_es->s_mount_opts,
4732 			 *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4733 
4734 	if (es->s_error_count)
4735 		mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4736 
4737 	/* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4738 	ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4739 	ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4740 	ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4741 
4742 	kfree(orig_data);
4743 	return 0;
4744 
4745 cantfind_ext4:
4746 	if (!silent)
4747 		ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4748 	goto failed_mount;
4749 
4750 #ifdef CONFIG_QUOTA
4751 failed_mount8:
4752 	ext4_unregister_sysfs(sb);
4753 #endif
4754 failed_mount7:
4755 	ext4_unregister_li_request(sb);
4756 failed_mount6:
4757 	ext4_mb_release(sb);
4758 	rcu_read_lock();
4759 	flex_groups = rcu_dereference(sbi->s_flex_groups);
4760 	if (flex_groups) {
4761 		for (i = 0; i < sbi->s_flex_groups_allocated; i++)
4762 			kvfree(flex_groups[i]);
4763 		kvfree(flex_groups);
4764 	}
4765 	rcu_read_unlock();
4766 	percpu_counter_destroy(&sbi->s_freeclusters_counter);
4767 	percpu_counter_destroy(&sbi->s_freeinodes_counter);
4768 	percpu_counter_destroy(&sbi->s_dirs_counter);
4769 	percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4770 	percpu_free_rwsem(&sbi->s_writepages_rwsem);
4771 failed_mount5:
4772 	ext4_ext_release(sb);
4773 	ext4_release_system_zone(sb);
4774 failed_mount4a:
4775 	dput(sb->s_root);
4776 	sb->s_root = NULL;
4777 failed_mount4:
4778 	ext4_msg(sb, KERN_ERR, "mount failed");
4779 	if (EXT4_SB(sb)->rsv_conversion_wq)
4780 		destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4781 failed_mount_wq:
4782 	ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4783 	sbi->s_ea_inode_cache = NULL;
4784 
4785 	ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4786 	sbi->s_ea_block_cache = NULL;
4787 
4788 	if (sbi->s_journal) {
4789 		jbd2_journal_destroy(sbi->s_journal);
4790 		sbi->s_journal = NULL;
4791 	}
4792 failed_mount3a:
4793 	ext4_es_unregister_shrinker(sbi);
4794 failed_mount3:
4795 	del_timer_sync(&sbi->s_err_report);
4796 	if (sbi->s_mmp_tsk)
4797 		kthread_stop(sbi->s_mmp_tsk);
4798 failed_mount2:
4799 	rcu_read_lock();
4800 	group_desc = rcu_dereference(sbi->s_group_desc);
4801 	for (i = 0; i < db_count; i++)
4802 		brelse(group_desc[i]);
4803 	kvfree(group_desc);
4804 	rcu_read_unlock();
4805 failed_mount:
4806 	if (sbi->s_chksum_driver)
4807 		crypto_free_shash(sbi->s_chksum_driver);
4808 
4809 #ifdef CONFIG_UNICODE
4810 	utf8_unload(sbi->s_encoding);
4811 #endif
4812 
4813 #ifdef CONFIG_QUOTA
4814 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
4815 		kfree(get_qf_name(sb, sbi, i));
4816 #endif
4817 	fscrypt_free_dummy_context(&sbi->s_dummy_enc_ctx);
4818 	ext4_blkdev_remove(sbi);
4819 	brelse(bh);
4820 out_fail:
4821 	sb->s_fs_info = NULL;
4822 	kfree(sbi->s_blockgroup_lock);
4823 out_free_base:
4824 	kfree(sbi);
4825 	kfree(orig_data);
4826 	fs_put_dax(dax_dev);
4827 	return err ? err : ret;
4828 }
4829 
4830 /*
4831  * Setup any per-fs journal parameters now.  We'll do this both on
4832  * initial mount, once the journal has been initialised but before we've
4833  * done any recovery; and again on any subsequent remount.
4834  */
4835 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4836 {
4837 	struct ext4_sb_info *sbi = EXT4_SB(sb);
4838 
4839 	journal->j_commit_interval = sbi->s_commit_interval;
4840 	journal->j_min_batch_time = sbi->s_min_batch_time;
4841 	journal->j_max_batch_time = sbi->s_max_batch_time;
4842 
4843 	write_lock(&journal->j_state_lock);
4844 	if (test_opt(sb, BARRIER))
4845 		journal->j_flags |= JBD2_BARRIER;
4846 	else
4847 		journal->j_flags &= ~JBD2_BARRIER;
4848 	if (test_opt(sb, DATA_ERR_ABORT))
4849 		journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4850 	else
4851 		journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4852 	write_unlock(&journal->j_state_lock);
4853 }
4854 
4855 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4856 					     unsigned int journal_inum)
4857 {
4858 	struct inode *journal_inode;
4859 
4860 	/*
4861 	 * Test for the existence of a valid inode on disk.  Bad things
4862 	 * happen if we iget() an unused inode, as the subsequent iput()
4863 	 * will try to delete it.
4864 	 */
4865 	journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4866 	if (IS_ERR(journal_inode)) {
4867 		ext4_msg(sb, KERN_ERR, "no journal found");
4868 		return NULL;
4869 	}
4870 	if (!journal_inode->i_nlink) {
4871 		make_bad_inode(journal_inode);
4872 		iput(journal_inode);
4873 		ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4874 		return NULL;
4875 	}
4876 
4877 	jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4878 		  journal_inode, journal_inode->i_size);
4879 	if (!S_ISREG(journal_inode->i_mode)) {
4880 		ext4_msg(sb, KERN_ERR, "invalid journal inode");
4881 		iput(journal_inode);
4882 		return NULL;
4883 	}
4884 	return journal_inode;
4885 }
4886 
4887 static journal_t *ext4_get_journal(struct super_block *sb,
4888 				   unsigned int journal_inum)
4889 {
4890 	struct inode *journal_inode;
4891 	journal_t *journal;
4892 
4893 	BUG_ON(!ext4_has_feature_journal(sb));
4894 
4895 	journal_inode = ext4_get_journal_inode(sb, journal_inum);
4896 	if (!journal_inode)
4897 		return NULL;
4898 
4899 	journal = jbd2_journal_init_inode(journal_inode);
4900 	if (!journal) {
4901 		ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4902 		iput(journal_inode);
4903 		return NULL;
4904 	}
4905 	journal->j_private = sb;
4906 	ext4_init_journal_params(sb, journal);
4907 	return journal;
4908 }
4909 
4910 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4911 				       dev_t j_dev)
4912 {
4913 	struct buffer_head *bh;
4914 	journal_t *journal;
4915 	ext4_fsblk_t start;
4916 	ext4_fsblk_t len;
4917 	int hblock, blocksize;
4918 	ext4_fsblk_t sb_block;
4919 	unsigned long offset;
4920 	struct ext4_super_block *es;
4921 	struct block_device *bdev;
4922 
4923 	BUG_ON(!ext4_has_feature_journal(sb));
4924 
4925 	bdev = ext4_blkdev_get(j_dev, sb);
4926 	if (bdev == NULL)
4927 		return NULL;
4928 
4929 	blocksize = sb->s_blocksize;
4930 	hblock = bdev_logical_block_size(bdev);
4931 	if (blocksize < hblock) {
4932 		ext4_msg(sb, KERN_ERR,
4933 			"blocksize too small for journal device");
4934 		goto out_bdev;
4935 	}
4936 
4937 	sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4938 	offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4939 	set_blocksize(bdev, blocksize);
4940 	if (!(bh = __bread(bdev, sb_block, blocksize))) {
4941 		ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4942 		       "external journal");
4943 		goto out_bdev;
4944 	}
4945 
4946 	es = (struct ext4_super_block *) (bh->b_data + offset);
4947 	if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4948 	    !(le32_to_cpu(es->s_feature_incompat) &
4949 	      EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4950 		ext4_msg(sb, KERN_ERR, "external journal has "
4951 					"bad superblock");
4952 		brelse(bh);
4953 		goto out_bdev;
4954 	}
4955 
4956 	if ((le32_to_cpu(es->s_feature_ro_compat) &
4957 	     EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4958 	    es->s_checksum != ext4_superblock_csum(sb, es)) {
4959 		ext4_msg(sb, KERN_ERR, "external journal has "
4960 				       "corrupt superblock");
4961 		brelse(bh);
4962 		goto out_bdev;
4963 	}
4964 
4965 	if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4966 		ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4967 		brelse(bh);
4968 		goto out_bdev;
4969 	}
4970 
4971 	len = ext4_blocks_count(es);
4972 	start = sb_block + 1;
4973 	brelse(bh);	/* we're done with the superblock */
4974 
4975 	journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4976 					start, len, blocksize);
4977 	if (!journal) {
4978 		ext4_msg(sb, KERN_ERR, "failed to create device journal");
4979 		goto out_bdev;
4980 	}
4981 	journal->j_private = sb;
4982 	ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4983 	wait_on_buffer(journal->j_sb_buffer);
4984 	if (!buffer_uptodate(journal->j_sb_buffer)) {
4985 		ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4986 		goto out_journal;
4987 	}
4988 	if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4989 		ext4_msg(sb, KERN_ERR, "External journal has more than one "
4990 					"user (unsupported) - %d",
4991 			be32_to_cpu(journal->j_superblock->s_nr_users));
4992 		goto out_journal;
4993 	}
4994 	EXT4_SB(sb)->journal_bdev = bdev;
4995 	ext4_init_journal_params(sb, journal);
4996 	return journal;
4997 
4998 out_journal:
4999 	jbd2_journal_destroy(journal);
5000 out_bdev:
5001 	ext4_blkdev_put(bdev);
5002 	return NULL;
5003 }
5004 
5005 static int ext4_load_journal(struct super_block *sb,
5006 			     struct ext4_super_block *es,
5007 			     unsigned long journal_devnum)
5008 {
5009 	journal_t *journal;
5010 	unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5011 	dev_t journal_dev;
5012 	int err = 0;
5013 	int really_read_only;
5014 
5015 	BUG_ON(!ext4_has_feature_journal(sb));
5016 
5017 	if (journal_devnum &&
5018 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5019 		ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5020 			"numbers have changed");
5021 		journal_dev = new_decode_dev(journal_devnum);
5022 	} else
5023 		journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5024 
5025 	really_read_only = bdev_read_only(sb->s_bdev);
5026 
5027 	/*
5028 	 * Are we loading a blank journal or performing recovery after a
5029 	 * crash?  For recovery, we need to check in advance whether we
5030 	 * can get read-write access to the device.
5031 	 */
5032 	if (ext4_has_feature_journal_needs_recovery(sb)) {
5033 		if (sb_rdonly(sb)) {
5034 			ext4_msg(sb, KERN_INFO, "INFO: recovery "
5035 					"required on readonly filesystem");
5036 			if (really_read_only) {
5037 				ext4_msg(sb, KERN_ERR, "write access "
5038 					"unavailable, cannot proceed "
5039 					"(try mounting with noload)");
5040 				return -EROFS;
5041 			}
5042 			ext4_msg(sb, KERN_INFO, "write access will "
5043 			       "be enabled during recovery");
5044 		}
5045 	}
5046 
5047 	if (journal_inum && journal_dev) {
5048 		ext4_msg(sb, KERN_ERR, "filesystem has both journal "
5049 		       "and inode journals!");
5050 		return -EINVAL;
5051 	}
5052 
5053 	if (journal_inum) {
5054 		if (!(journal = ext4_get_journal(sb, journal_inum)))
5055 			return -EINVAL;
5056 	} else {
5057 		if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
5058 			return -EINVAL;
5059 	}
5060 
5061 	if (!(journal->j_flags & JBD2_BARRIER))
5062 		ext4_msg(sb, KERN_INFO, "barriers disabled");
5063 
5064 	if (!ext4_has_feature_journal_needs_recovery(sb))
5065 		err = jbd2_journal_wipe(journal, !really_read_only);
5066 	if (!err) {
5067 		char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5068 		if (save)
5069 			memcpy(save, ((char *) es) +
5070 			       EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5071 		err = jbd2_journal_load(journal);
5072 		if (save)
5073 			memcpy(((char *) es) + EXT4_S_ERR_START,
5074 			       save, EXT4_S_ERR_LEN);
5075 		kfree(save);
5076 	}
5077 
5078 	if (err) {
5079 		ext4_msg(sb, KERN_ERR, "error loading journal");
5080 		jbd2_journal_destroy(journal);
5081 		return err;
5082 	}
5083 
5084 	EXT4_SB(sb)->s_journal = journal;
5085 	ext4_clear_journal_err(sb, es);
5086 
5087 	if (!really_read_only && journal_devnum &&
5088 	    journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5089 		es->s_journal_dev = cpu_to_le32(journal_devnum);
5090 
5091 		/* Make sure we flush the recovery flag to disk. */
5092 		ext4_commit_super(sb, 1);
5093 	}
5094 
5095 	return 0;
5096 }
5097 
5098 static int ext4_commit_super(struct super_block *sb, int sync)
5099 {
5100 	struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5101 	struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5102 	int error = 0;
5103 
5104 	if (!sbh || block_device_ejected(sb))
5105 		return error;
5106 
5107 	/*
5108 	 * The superblock bh should be mapped, but it might not be if the
5109 	 * device was hot-removed. Not much we can do but fail the I/O.
5110 	 */
5111 	if (!buffer_mapped(sbh))
5112 		return error;
5113 
5114 	/*
5115 	 * If the file system is mounted read-only, don't update the
5116 	 * superblock write time.  This avoids updating the superblock
5117 	 * write time when we are mounting the root file system
5118 	 * read/only but we need to replay the journal; at that point,
5119 	 * for people who are east of GMT and who make their clock
5120 	 * tick in localtime for Windows bug-for-bug compatibility,
5121 	 * the clock is set in the future, and this will cause e2fsck
5122 	 * to complain and force a full file system check.
5123 	 */
5124 	if (!(sb->s_flags & SB_RDONLY))
5125 		ext4_update_tstamp(es, s_wtime);
5126 	if (sb->s_bdev->bd_part)
5127 		es->s_kbytes_written =
5128 			cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5129 			    ((part_stat_read(sb->s_bdev->bd_part,
5130 					     sectors[STAT_WRITE]) -
5131 			      EXT4_SB(sb)->s_sectors_written_start) >> 1));
5132 	else
5133 		es->s_kbytes_written =
5134 			cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5135 	if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5136 		ext4_free_blocks_count_set(es,
5137 			EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5138 				&EXT4_SB(sb)->s_freeclusters_counter)));
5139 	if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5140 		es->s_free_inodes_count =
5141 			cpu_to_le32(percpu_counter_sum_positive(
5142 				&EXT4_SB(sb)->s_freeinodes_counter));
5143 	BUFFER_TRACE(sbh, "marking dirty");
5144 	ext4_superblock_csum_set(sb);
5145 	if (sync)
5146 		lock_buffer(sbh);
5147 	if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5148 		/*
5149 		 * Oh, dear.  A previous attempt to write the
5150 		 * superblock failed.  This could happen because the
5151 		 * USB device was yanked out.  Or it could happen to
5152 		 * be a transient write error and maybe the block will
5153 		 * be remapped.  Nothing we can do but to retry the
5154 		 * write and hope for the best.
5155 		 */
5156 		ext4_msg(sb, KERN_ERR, "previous I/O error to "
5157 		       "superblock detected");
5158 		clear_buffer_write_io_error(sbh);
5159 		set_buffer_uptodate(sbh);
5160 	}
5161 	mark_buffer_dirty(sbh);
5162 	if (sync) {
5163 		unlock_buffer(sbh);
5164 		error = __sync_dirty_buffer(sbh,
5165 			REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5166 		if (buffer_write_io_error(sbh)) {
5167 			ext4_msg(sb, KERN_ERR, "I/O error while writing "
5168 			       "superblock");
5169 			clear_buffer_write_io_error(sbh);
5170 			set_buffer_uptodate(sbh);
5171 		}
5172 	}
5173 	return error;
5174 }
5175 
5176 /*
5177  * Have we just finished recovery?  If so, and if we are mounting (or
5178  * remounting) the filesystem readonly, then we will end up with a
5179  * consistent fs on disk.  Record that fact.
5180  */
5181 static void ext4_mark_recovery_complete(struct super_block *sb,
5182 					struct ext4_super_block *es)
5183 {
5184 	journal_t *journal = EXT4_SB(sb)->s_journal;
5185 
5186 	if (!ext4_has_feature_journal(sb)) {
5187 		BUG_ON(journal != NULL);
5188 		return;
5189 	}
5190 	jbd2_journal_lock_updates(journal);
5191 	if (jbd2_journal_flush(journal) < 0)
5192 		goto out;
5193 
5194 	if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5195 		ext4_clear_feature_journal_needs_recovery(sb);
5196 		ext4_commit_super(sb, 1);
5197 	}
5198 
5199 out:
5200 	jbd2_journal_unlock_updates(journal);
5201 }
5202 
5203 /*
5204  * If we are mounting (or read-write remounting) a filesystem whose journal
5205  * has recorded an error from a previous lifetime, move that error to the
5206  * main filesystem now.
5207  */
5208 static void ext4_clear_journal_err(struct super_block *sb,
5209 				   struct ext4_super_block *es)
5210 {
5211 	journal_t *journal;
5212 	int j_errno;
5213 	const char *errstr;
5214 
5215 	BUG_ON(!ext4_has_feature_journal(sb));
5216 
5217 	journal = EXT4_SB(sb)->s_journal;
5218 
5219 	/*
5220 	 * Now check for any error status which may have been recorded in the
5221 	 * journal by a prior ext4_error() or ext4_abort()
5222 	 */
5223 
5224 	j_errno = jbd2_journal_errno(journal);
5225 	if (j_errno) {
5226 		char nbuf[16];
5227 
5228 		errstr = ext4_decode_error(sb, j_errno, nbuf);
5229 		ext4_warning(sb, "Filesystem error recorded "
5230 			     "from previous mount: %s", errstr);
5231 		ext4_warning(sb, "Marking fs in need of filesystem check.");
5232 
5233 		EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5234 		es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5235 		ext4_commit_super(sb, 1);
5236 
5237 		jbd2_journal_clear_err(journal);
5238 		jbd2_journal_update_sb_errno(journal);
5239 	}
5240 }
5241 
5242 /*
5243  * Force the running and committing transactions to commit,
5244  * and wait on the commit.
5245  */
5246 int ext4_force_commit(struct super_block *sb)
5247 {
5248 	journal_t *journal;
5249 
5250 	if (sb_rdonly(sb))
5251 		return 0;
5252 
5253 	journal = EXT4_SB(sb)->s_journal;
5254 	return ext4_journal_force_commit(journal);
5255 }
5256 
5257 static int ext4_sync_fs(struct super_block *sb, int wait)
5258 {
5259 	int ret = 0;
5260 	tid_t target;
5261 	bool needs_barrier = false;
5262 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5263 
5264 	if (unlikely(ext4_forced_shutdown(sbi)))
5265 		return 0;
5266 
5267 	trace_ext4_sync_fs(sb, wait);
5268 	flush_workqueue(sbi->rsv_conversion_wq);
5269 	/*
5270 	 * Writeback quota in non-journalled quota case - journalled quota has
5271 	 * no dirty dquots
5272 	 */
5273 	dquot_writeback_dquots(sb, -1);
5274 	/*
5275 	 * Data writeback is possible w/o journal transaction, so barrier must
5276 	 * being sent at the end of the function. But we can skip it if
5277 	 * transaction_commit will do it for us.
5278 	 */
5279 	if (sbi->s_journal) {
5280 		target = jbd2_get_latest_transaction(sbi->s_journal);
5281 		if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5282 		    !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5283 			needs_barrier = true;
5284 
5285 		if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5286 			if (wait)
5287 				ret = jbd2_log_wait_commit(sbi->s_journal,
5288 							   target);
5289 		}
5290 	} else if (wait && test_opt(sb, BARRIER))
5291 		needs_barrier = true;
5292 	if (needs_barrier) {
5293 		int err;
5294 		err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
5295 		if (!ret)
5296 			ret = err;
5297 	}
5298 
5299 	return ret;
5300 }
5301 
5302 /*
5303  * LVM calls this function before a (read-only) snapshot is created.  This
5304  * gives us a chance to flush the journal completely and mark the fs clean.
5305  *
5306  * Note that only this function cannot bring a filesystem to be in a clean
5307  * state independently. It relies on upper layer to stop all data & metadata
5308  * modifications.
5309  */
5310 static int ext4_freeze(struct super_block *sb)
5311 {
5312 	int error = 0;
5313 	journal_t *journal;
5314 
5315 	if (sb_rdonly(sb))
5316 		return 0;
5317 
5318 	journal = EXT4_SB(sb)->s_journal;
5319 
5320 	if (journal) {
5321 		/* Now we set up the journal barrier. */
5322 		jbd2_journal_lock_updates(journal);
5323 
5324 		/*
5325 		 * Don't clear the needs_recovery flag if we failed to
5326 		 * flush the journal.
5327 		 */
5328 		error = jbd2_journal_flush(journal);
5329 		if (error < 0)
5330 			goto out;
5331 
5332 		/* Journal blocked and flushed, clear needs_recovery flag. */
5333 		ext4_clear_feature_journal_needs_recovery(sb);
5334 	}
5335 
5336 	error = ext4_commit_super(sb, 1);
5337 out:
5338 	if (journal)
5339 		/* we rely on upper layer to stop further updates */
5340 		jbd2_journal_unlock_updates(journal);
5341 	return error;
5342 }
5343 
5344 /*
5345  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5346  * flag here, even though the filesystem is not technically dirty yet.
5347  */
5348 static int ext4_unfreeze(struct super_block *sb)
5349 {
5350 	if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5351 		return 0;
5352 
5353 	if (EXT4_SB(sb)->s_journal) {
5354 		/* Reset the needs_recovery flag before the fs is unlocked. */
5355 		ext4_set_feature_journal_needs_recovery(sb);
5356 	}
5357 
5358 	ext4_commit_super(sb, 1);
5359 	return 0;
5360 }
5361 
5362 /*
5363  * Structure to save mount options for ext4_remount's benefit
5364  */
5365 struct ext4_mount_options {
5366 	unsigned long s_mount_opt;
5367 	unsigned long s_mount_opt2;
5368 	kuid_t s_resuid;
5369 	kgid_t s_resgid;
5370 	unsigned long s_commit_interval;
5371 	u32 s_min_batch_time, s_max_batch_time;
5372 #ifdef CONFIG_QUOTA
5373 	int s_jquota_fmt;
5374 	char *s_qf_names[EXT4_MAXQUOTAS];
5375 #endif
5376 };
5377 
5378 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5379 {
5380 	struct ext4_super_block *es;
5381 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5382 	unsigned long old_sb_flags;
5383 	struct ext4_mount_options old_opts;
5384 	int enable_quota = 0;
5385 	ext4_group_t g;
5386 	unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5387 	int err = 0;
5388 #ifdef CONFIG_QUOTA
5389 	int i, j;
5390 	char *to_free[EXT4_MAXQUOTAS];
5391 #endif
5392 	char *orig_data = kstrdup(data, GFP_KERNEL);
5393 
5394 	if (data && !orig_data)
5395 		return -ENOMEM;
5396 
5397 	/* Store the original options */
5398 	old_sb_flags = sb->s_flags;
5399 	old_opts.s_mount_opt = sbi->s_mount_opt;
5400 	old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5401 	old_opts.s_resuid = sbi->s_resuid;
5402 	old_opts.s_resgid = sbi->s_resgid;
5403 	old_opts.s_commit_interval = sbi->s_commit_interval;
5404 	old_opts.s_min_batch_time = sbi->s_min_batch_time;
5405 	old_opts.s_max_batch_time = sbi->s_max_batch_time;
5406 #ifdef CONFIG_QUOTA
5407 	old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5408 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5409 		if (sbi->s_qf_names[i]) {
5410 			char *qf_name = get_qf_name(sb, sbi, i);
5411 
5412 			old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5413 			if (!old_opts.s_qf_names[i]) {
5414 				for (j = 0; j < i; j++)
5415 					kfree(old_opts.s_qf_names[j]);
5416 				kfree(orig_data);
5417 				return -ENOMEM;
5418 			}
5419 		} else
5420 			old_opts.s_qf_names[i] = NULL;
5421 #endif
5422 	if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5423 		journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5424 
5425 	if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5426 		err = -EINVAL;
5427 		goto restore_opts;
5428 	}
5429 
5430 	if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5431 	    test_opt(sb, JOURNAL_CHECKSUM)) {
5432 		ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5433 			 "during remount not supported; ignoring");
5434 		sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5435 	}
5436 
5437 	if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5438 		if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5439 			ext4_msg(sb, KERN_ERR, "can't mount with "
5440 				 "both data=journal and delalloc");
5441 			err = -EINVAL;
5442 			goto restore_opts;
5443 		}
5444 		if (test_opt(sb, DIOREAD_NOLOCK)) {
5445 			ext4_msg(sb, KERN_ERR, "can't mount with "
5446 				 "both data=journal and dioread_nolock");
5447 			err = -EINVAL;
5448 			goto restore_opts;
5449 		}
5450 		if (test_opt(sb, DAX)) {
5451 			ext4_msg(sb, KERN_ERR, "can't mount with "
5452 				 "both data=journal and dax");
5453 			err = -EINVAL;
5454 			goto restore_opts;
5455 		}
5456 	} else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5457 		if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5458 			ext4_msg(sb, KERN_ERR, "can't mount with "
5459 				"journal_async_commit in data=ordered mode");
5460 			err = -EINVAL;
5461 			goto restore_opts;
5462 		}
5463 	}
5464 
5465 	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5466 		ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5467 		err = -EINVAL;
5468 		goto restore_opts;
5469 	}
5470 
5471 	if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5472 		ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5473 			"dax flag with busy inodes while remounting");
5474 		sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5475 	}
5476 
5477 	if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5478 		ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5479 
5480 	sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5481 		(test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5482 
5483 	es = sbi->s_es;
5484 
5485 	if (sbi->s_journal) {
5486 		ext4_init_journal_params(sb, sbi->s_journal);
5487 		set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5488 	}
5489 
5490 	if (*flags & SB_LAZYTIME)
5491 		sb->s_flags |= SB_LAZYTIME;
5492 
5493 	if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5494 		if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5495 			err = -EROFS;
5496 			goto restore_opts;
5497 		}
5498 
5499 		if (*flags & SB_RDONLY) {
5500 			err = sync_filesystem(sb);
5501 			if (err < 0)
5502 				goto restore_opts;
5503 			err = dquot_suspend(sb, -1);
5504 			if (err < 0)
5505 				goto restore_opts;
5506 
5507 			/*
5508 			 * First of all, the unconditional stuff we have to do
5509 			 * to disable replay of the journal when we next remount
5510 			 */
5511 			sb->s_flags |= SB_RDONLY;
5512 
5513 			/*
5514 			 * OK, test if we are remounting a valid rw partition
5515 			 * readonly, and if so set the rdonly flag and then
5516 			 * mark the partition as valid again.
5517 			 */
5518 			if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5519 			    (sbi->s_mount_state & EXT4_VALID_FS))
5520 				es->s_state = cpu_to_le16(sbi->s_mount_state);
5521 
5522 			if (sbi->s_journal)
5523 				ext4_mark_recovery_complete(sb, es);
5524 			if (sbi->s_mmp_tsk)
5525 				kthread_stop(sbi->s_mmp_tsk);
5526 		} else {
5527 			/* Make sure we can mount this feature set readwrite */
5528 			if (ext4_has_feature_readonly(sb) ||
5529 			    !ext4_feature_set_ok(sb, 0)) {
5530 				err = -EROFS;
5531 				goto restore_opts;
5532 			}
5533 			/*
5534 			 * Make sure the group descriptor checksums
5535 			 * are sane.  If they aren't, refuse to remount r/w.
5536 			 */
5537 			for (g = 0; g < sbi->s_groups_count; g++) {
5538 				struct ext4_group_desc *gdp =
5539 					ext4_get_group_desc(sb, g, NULL);
5540 
5541 				if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5542 					ext4_msg(sb, KERN_ERR,
5543 	       "ext4_remount: Checksum for group %u failed (%u!=%u)",
5544 		g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5545 					       le16_to_cpu(gdp->bg_checksum));
5546 					err = -EFSBADCRC;
5547 					goto restore_opts;
5548 				}
5549 			}
5550 
5551 			/*
5552 			 * If we have an unprocessed orphan list hanging
5553 			 * around from a previously readonly bdev mount,
5554 			 * require a full umount/remount for now.
5555 			 */
5556 			if (es->s_last_orphan) {
5557 				ext4_msg(sb, KERN_WARNING, "Couldn't "
5558 				       "remount RDWR because of unprocessed "
5559 				       "orphan inode list.  Please "
5560 				       "umount/remount instead");
5561 				err = -EINVAL;
5562 				goto restore_opts;
5563 			}
5564 
5565 			/*
5566 			 * Mounting a RDONLY partition read-write, so reread
5567 			 * and store the current valid flag.  (It may have
5568 			 * been changed by e2fsck since we originally mounted
5569 			 * the partition.)
5570 			 */
5571 			if (sbi->s_journal)
5572 				ext4_clear_journal_err(sb, es);
5573 			sbi->s_mount_state = le16_to_cpu(es->s_state);
5574 
5575 			err = ext4_setup_super(sb, es, 0);
5576 			if (err)
5577 				goto restore_opts;
5578 
5579 			sb->s_flags &= ~SB_RDONLY;
5580 			if (ext4_has_feature_mmp(sb))
5581 				if (ext4_multi_mount_protect(sb,
5582 						le64_to_cpu(es->s_mmp_block))) {
5583 					err = -EROFS;
5584 					goto restore_opts;
5585 				}
5586 			enable_quota = 1;
5587 		}
5588 	}
5589 
5590 	/*
5591 	 * Reinitialize lazy itable initialization thread based on
5592 	 * current settings
5593 	 */
5594 	if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5595 		ext4_unregister_li_request(sb);
5596 	else {
5597 		ext4_group_t first_not_zeroed;
5598 		first_not_zeroed = ext4_has_uninit_itable(sb);
5599 		ext4_register_li_request(sb, first_not_zeroed);
5600 	}
5601 
5602 	ext4_setup_system_zone(sb);
5603 	if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5604 		err = ext4_commit_super(sb, 1);
5605 		if (err)
5606 			goto restore_opts;
5607 	}
5608 
5609 #ifdef CONFIG_QUOTA
5610 	/* Release old quota file names */
5611 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5612 		kfree(old_opts.s_qf_names[i]);
5613 	if (enable_quota) {
5614 		if (sb_any_quota_suspended(sb))
5615 			dquot_resume(sb, -1);
5616 		else if (ext4_has_feature_quota(sb)) {
5617 			err = ext4_enable_quotas(sb);
5618 			if (err)
5619 				goto restore_opts;
5620 		}
5621 	}
5622 #endif
5623 
5624 	*flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5625 	ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5626 	kfree(orig_data);
5627 	return 0;
5628 
5629 restore_opts:
5630 	sb->s_flags = old_sb_flags;
5631 	sbi->s_mount_opt = old_opts.s_mount_opt;
5632 	sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5633 	sbi->s_resuid = old_opts.s_resuid;
5634 	sbi->s_resgid = old_opts.s_resgid;
5635 	sbi->s_commit_interval = old_opts.s_commit_interval;
5636 	sbi->s_min_batch_time = old_opts.s_min_batch_time;
5637 	sbi->s_max_batch_time = old_opts.s_max_batch_time;
5638 #ifdef CONFIG_QUOTA
5639 	sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5640 	for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5641 		to_free[i] = get_qf_name(sb, sbi, i);
5642 		rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5643 	}
5644 	synchronize_rcu();
5645 	for (i = 0; i < EXT4_MAXQUOTAS; i++)
5646 		kfree(to_free[i]);
5647 #endif
5648 	kfree(orig_data);
5649 	return err;
5650 }
5651 
5652 #ifdef CONFIG_QUOTA
5653 static int ext4_statfs_project(struct super_block *sb,
5654 			       kprojid_t projid, struct kstatfs *buf)
5655 {
5656 	struct kqid qid;
5657 	struct dquot *dquot;
5658 	u64 limit;
5659 	u64 curblock;
5660 
5661 	qid = make_kqid_projid(projid);
5662 	dquot = dqget(sb, qid);
5663 	if (IS_ERR(dquot))
5664 		return PTR_ERR(dquot);
5665 	spin_lock(&dquot->dq_dqb_lock);
5666 
5667 	limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
5668 			     dquot->dq_dqb.dqb_bhardlimit);
5669 	limit >>= sb->s_blocksize_bits;
5670 
5671 	if (limit && buf->f_blocks > limit) {
5672 		curblock = (dquot->dq_dqb.dqb_curspace +
5673 			    dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5674 		buf->f_blocks = limit;
5675 		buf->f_bfree = buf->f_bavail =
5676 			(buf->f_blocks > curblock) ?
5677 			 (buf->f_blocks - curblock) : 0;
5678 	}
5679 
5680 	limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
5681 			     dquot->dq_dqb.dqb_ihardlimit);
5682 	if (limit && buf->f_files > limit) {
5683 		buf->f_files = limit;
5684 		buf->f_ffree =
5685 			(buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5686 			 (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5687 	}
5688 
5689 	spin_unlock(&dquot->dq_dqb_lock);
5690 	dqput(dquot);
5691 	return 0;
5692 }
5693 #endif
5694 
5695 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5696 {
5697 	struct super_block *sb = dentry->d_sb;
5698 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5699 	struct ext4_super_block *es = sbi->s_es;
5700 	ext4_fsblk_t overhead = 0, resv_blocks;
5701 	u64 fsid;
5702 	s64 bfree;
5703 	resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5704 
5705 	if (!test_opt(sb, MINIX_DF))
5706 		overhead = sbi->s_overhead;
5707 
5708 	buf->f_type = EXT4_SUPER_MAGIC;
5709 	buf->f_bsize = sb->s_blocksize;
5710 	buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5711 	bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5712 		percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5713 	/* prevent underflow in case that few free space is available */
5714 	buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5715 	buf->f_bavail = buf->f_bfree -
5716 			(ext4_r_blocks_count(es) + resv_blocks);
5717 	if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5718 		buf->f_bavail = 0;
5719 	buf->f_files = le32_to_cpu(es->s_inodes_count);
5720 	buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5721 	buf->f_namelen = EXT4_NAME_LEN;
5722 	fsid = le64_to_cpup((void *)es->s_uuid) ^
5723 	       le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5724 	buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5725 	buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5726 
5727 #ifdef CONFIG_QUOTA
5728 	if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5729 	    sb_has_quota_limits_enabled(sb, PRJQUOTA))
5730 		ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5731 #endif
5732 	return 0;
5733 }
5734 
5735 
5736 #ifdef CONFIG_QUOTA
5737 
5738 /*
5739  * Helper functions so that transaction is started before we acquire dqio_sem
5740  * to keep correct lock ordering of transaction > dqio_sem
5741  */
5742 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5743 {
5744 	return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5745 }
5746 
5747 static int ext4_write_dquot(struct dquot *dquot)
5748 {
5749 	int ret, err;
5750 	handle_t *handle;
5751 	struct inode *inode;
5752 
5753 	inode = dquot_to_inode(dquot);
5754 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5755 				    EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5756 	if (IS_ERR(handle))
5757 		return PTR_ERR(handle);
5758 	ret = dquot_commit(dquot);
5759 	err = ext4_journal_stop(handle);
5760 	if (!ret)
5761 		ret = err;
5762 	return ret;
5763 }
5764 
5765 static int ext4_acquire_dquot(struct dquot *dquot)
5766 {
5767 	int ret, err;
5768 	handle_t *handle;
5769 
5770 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5771 				    EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5772 	if (IS_ERR(handle))
5773 		return PTR_ERR(handle);
5774 	ret = dquot_acquire(dquot);
5775 	err = ext4_journal_stop(handle);
5776 	if (!ret)
5777 		ret = err;
5778 	return ret;
5779 }
5780 
5781 static int ext4_release_dquot(struct dquot *dquot)
5782 {
5783 	int ret, err;
5784 	handle_t *handle;
5785 
5786 	handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5787 				    EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5788 	if (IS_ERR(handle)) {
5789 		/* Release dquot anyway to avoid endless cycle in dqput() */
5790 		dquot_release(dquot);
5791 		return PTR_ERR(handle);
5792 	}
5793 	ret = dquot_release(dquot);
5794 	err = ext4_journal_stop(handle);
5795 	if (!ret)
5796 		ret = err;
5797 	return ret;
5798 }
5799 
5800 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5801 {
5802 	struct super_block *sb = dquot->dq_sb;
5803 	struct ext4_sb_info *sbi = EXT4_SB(sb);
5804 
5805 	/* Are we journaling quotas? */
5806 	if (ext4_has_feature_quota(sb) ||
5807 	    sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5808 		dquot_mark_dquot_dirty(dquot);
5809 		return ext4_write_dquot(dquot);
5810 	} else {
5811 		return dquot_mark_dquot_dirty(dquot);
5812 	}
5813 }
5814 
5815 static int ext4_write_info(struct super_block *sb, int type)
5816 {
5817 	int ret, err;
5818 	handle_t *handle;
5819 
5820 	/* Data block + inode block */
5821 	handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5822 	if (IS_ERR(handle))
5823 		return PTR_ERR(handle);
5824 	ret = dquot_commit_info(sb, type);
5825 	err = ext4_journal_stop(handle);
5826 	if (!ret)
5827 		ret = err;
5828 	return ret;
5829 }
5830 
5831 /*
5832  * Turn on quotas during mount time - we need to find
5833  * the quota file and such...
5834  */
5835 static int ext4_quota_on_mount(struct super_block *sb, int type)
5836 {
5837 	return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5838 					EXT4_SB(sb)->s_jquota_fmt, type);
5839 }
5840 
5841 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5842 {
5843 	struct ext4_inode_info *ei = EXT4_I(inode);
5844 
5845 	/* The first argument of lockdep_set_subclass has to be
5846 	 * *exactly* the same as the argument to init_rwsem() --- in
5847 	 * this case, in init_once() --- or lockdep gets unhappy
5848 	 * because the name of the lock is set using the
5849 	 * stringification of the argument to init_rwsem().
5850 	 */
5851 	(void) ei;	/* shut up clang warning if !CONFIG_LOCKDEP */
5852 	lockdep_set_subclass(&ei->i_data_sem, subclass);
5853 }
5854 
5855 /*
5856  * Standard function to be called on quota_on
5857  */
5858 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5859 			 const struct path *path)
5860 {
5861 	int err;
5862 
5863 	if (!test_opt(sb, QUOTA))
5864 		return -EINVAL;
5865 
5866 	/* Quotafile not on the same filesystem? */
5867 	if (path->dentry->d_sb != sb)
5868 		return -EXDEV;
5869 	/* Journaling quota? */
5870 	if (EXT4_SB(sb)->s_qf_names[type]) {
5871 		/* Quotafile not in fs root? */
5872 		if (path->dentry->d_parent != sb->s_root)
5873 			ext4_msg(sb, KERN_WARNING,
5874 				"Quota file not on filesystem root. "
5875 				"Journaled quota will not work");
5876 		sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5877 	} else {
5878 		/*
5879 		 * Clear the flag just in case mount options changed since
5880 		 * last time.
5881 		 */
5882 		sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5883 	}
5884 
5885 	/*
5886 	 * When we journal data on quota file, we have to flush journal to see
5887 	 * all updates to the file when we bypass pagecache...
5888 	 */
5889 	if (EXT4_SB(sb)->s_journal &&
5890 	    ext4_should_journal_data(d_inode(path->dentry))) {
5891 		/*
5892 		 * We don't need to lock updates but journal_flush() could
5893 		 * otherwise be livelocked...
5894 		 */
5895 		jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5896 		err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5897 		jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5898 		if (err)
5899 			return err;
5900 	}
5901 
5902 	lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5903 	err = dquot_quota_on(sb, type, format_id, path);
5904 	if (err) {
5905 		lockdep_set_quota_inode(path->dentry->d_inode,
5906 					     I_DATA_SEM_NORMAL);
5907 	} else {
5908 		struct inode *inode = d_inode(path->dentry);
5909 		handle_t *handle;
5910 
5911 		/*
5912 		 * Set inode flags to prevent userspace from messing with quota
5913 		 * files. If this fails, we return success anyway since quotas
5914 		 * are already enabled and this is not a hard failure.
5915 		 */
5916 		inode_lock(inode);
5917 		handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5918 		if (IS_ERR(handle))
5919 			goto unlock_inode;
5920 		EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5921 		inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5922 				S_NOATIME | S_IMMUTABLE);
5923 		err = ext4_mark_inode_dirty(handle, inode);
5924 		ext4_journal_stop(handle);
5925 	unlock_inode:
5926 		inode_unlock(inode);
5927 	}
5928 	return err;
5929 }
5930 
5931 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5932 			     unsigned int flags)
5933 {
5934 	int err;
5935 	struct inode *qf_inode;
5936 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5937 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5938 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5939 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5940 	};
5941 
5942 	BUG_ON(!ext4_has_feature_quota(sb));
5943 
5944 	if (!qf_inums[type])
5945 		return -EPERM;
5946 
5947 	qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5948 	if (IS_ERR(qf_inode)) {
5949 		ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5950 		return PTR_ERR(qf_inode);
5951 	}
5952 
5953 	/* Don't account quota for quota files to avoid recursion */
5954 	qf_inode->i_flags |= S_NOQUOTA;
5955 	lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5956 	err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
5957 	if (err)
5958 		lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5959 	iput(qf_inode);
5960 
5961 	return err;
5962 }
5963 
5964 /* Enable usage tracking for all quota types. */
5965 static int ext4_enable_quotas(struct super_block *sb)
5966 {
5967 	int type, err = 0;
5968 	unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5969 		le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5970 		le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5971 		le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5972 	};
5973 	bool quota_mopt[EXT4_MAXQUOTAS] = {
5974 		test_opt(sb, USRQUOTA),
5975 		test_opt(sb, GRPQUOTA),
5976 		test_opt(sb, PRJQUOTA),
5977 	};
5978 
5979 	sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5980 	for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5981 		if (qf_inums[type]) {
5982 			err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5983 				DQUOT_USAGE_ENABLED |
5984 				(quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5985 			if (err) {
5986 				ext4_warning(sb,
5987 					"Failed to enable quota tracking "
5988 					"(type=%d, err=%d). Please run "
5989 					"e2fsck to fix.", type, err);
5990 				for (type--; type >= 0; type--)
5991 					dquot_quota_off(sb, type);
5992 
5993 				return err;
5994 			}
5995 		}
5996 	}
5997 	return 0;
5998 }
5999 
6000 static int ext4_quota_off(struct super_block *sb, int type)
6001 {
6002 	struct inode *inode = sb_dqopt(sb)->files[type];
6003 	handle_t *handle;
6004 	int err;
6005 
6006 	/* Force all delayed allocation blocks to be allocated.
6007 	 * Caller already holds s_umount sem */
6008 	if (test_opt(sb, DELALLOC))
6009 		sync_filesystem(sb);
6010 
6011 	if (!inode || !igrab(inode))
6012 		goto out;
6013 
6014 	err = dquot_quota_off(sb, type);
6015 	if (err || ext4_has_feature_quota(sb))
6016 		goto out_put;
6017 
6018 	inode_lock(inode);
6019 	/*
6020 	 * Update modification times of quota files when userspace can
6021 	 * start looking at them. If we fail, we return success anyway since
6022 	 * this is not a hard failure and quotas are already disabled.
6023 	 */
6024 	handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6025 	if (IS_ERR(handle)) {
6026 		err = PTR_ERR(handle);
6027 		goto out_unlock;
6028 	}
6029 	EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6030 	inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6031 	inode->i_mtime = inode->i_ctime = current_time(inode);
6032 	err = ext4_mark_inode_dirty(handle, inode);
6033 	ext4_journal_stop(handle);
6034 out_unlock:
6035 	inode_unlock(inode);
6036 out_put:
6037 	lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6038 	iput(inode);
6039 	return err;
6040 out:
6041 	return dquot_quota_off(sb, type);
6042 }
6043 
6044 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6045  * acquiring the locks... As quota files are never truncated and quota code
6046  * itself serializes the operations (and no one else should touch the files)
6047  * we don't have to be afraid of races */
6048 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6049 			       size_t len, loff_t off)
6050 {
6051 	struct inode *inode = sb_dqopt(sb)->files[type];
6052 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6053 	int offset = off & (sb->s_blocksize - 1);
6054 	int tocopy;
6055 	size_t toread;
6056 	struct buffer_head *bh;
6057 	loff_t i_size = i_size_read(inode);
6058 
6059 	if (off > i_size)
6060 		return 0;
6061 	if (off+len > i_size)
6062 		len = i_size-off;
6063 	toread = len;
6064 	while (toread > 0) {
6065 		tocopy = sb->s_blocksize - offset < toread ?
6066 				sb->s_blocksize - offset : toread;
6067 		bh = ext4_bread(NULL, inode, blk, 0);
6068 		if (IS_ERR(bh))
6069 			return PTR_ERR(bh);
6070 		if (!bh)	/* A hole? */
6071 			memset(data, 0, tocopy);
6072 		else
6073 			memcpy(data, bh->b_data+offset, tocopy);
6074 		brelse(bh);
6075 		offset = 0;
6076 		toread -= tocopy;
6077 		data += tocopy;
6078 		blk++;
6079 	}
6080 	return len;
6081 }
6082 
6083 /* Write to quotafile (we know the transaction is already started and has
6084  * enough credits) */
6085 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6086 				const char *data, size_t len, loff_t off)
6087 {
6088 	struct inode *inode = sb_dqopt(sb)->files[type];
6089 	ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6090 	int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6091 	int retries = 0;
6092 	struct buffer_head *bh;
6093 	handle_t *handle = journal_current_handle();
6094 
6095 	if (EXT4_SB(sb)->s_journal && !handle) {
6096 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6097 			" cancelled because transaction is not started",
6098 			(unsigned long long)off, (unsigned long long)len);
6099 		return -EIO;
6100 	}
6101 	/*
6102 	 * Since we account only one data block in transaction credits,
6103 	 * then it is impossible to cross a block boundary.
6104 	 */
6105 	if (sb->s_blocksize - offset < len) {
6106 		ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6107 			" cancelled because not block aligned",
6108 			(unsigned long long)off, (unsigned long long)len);
6109 		return -EIO;
6110 	}
6111 
6112 	do {
6113 		bh = ext4_bread(handle, inode, blk,
6114 				EXT4_GET_BLOCKS_CREATE |
6115 				EXT4_GET_BLOCKS_METADATA_NOFAIL);
6116 	} while (PTR_ERR(bh) == -ENOSPC &&
6117 		 ext4_should_retry_alloc(inode->i_sb, &retries));
6118 	if (IS_ERR(bh))
6119 		return PTR_ERR(bh);
6120 	if (!bh)
6121 		goto out;
6122 	BUFFER_TRACE(bh, "get write access");
6123 	err = ext4_journal_get_write_access(handle, bh);
6124 	if (err) {
6125 		brelse(bh);
6126 		return err;
6127 	}
6128 	lock_buffer(bh);
6129 	memcpy(bh->b_data+offset, data, len);
6130 	flush_dcache_page(bh->b_page);
6131 	unlock_buffer(bh);
6132 	err = ext4_handle_dirty_metadata(handle, NULL, bh);
6133 	brelse(bh);
6134 out:
6135 	if (inode->i_size < off + len) {
6136 		i_size_write(inode, off + len);
6137 		EXT4_I(inode)->i_disksize = inode->i_size;
6138 		err2 = ext4_mark_inode_dirty(handle, inode);
6139 		if (unlikely(err2 && !err))
6140 			err = err2;
6141 	}
6142 	return err ? err : len;
6143 }
6144 #endif
6145 
6146 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6147 		       const char *dev_name, void *data)
6148 {
6149 	return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6150 }
6151 
6152 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6153 static inline void register_as_ext2(void)
6154 {
6155 	int err = register_filesystem(&ext2_fs_type);
6156 	if (err)
6157 		printk(KERN_WARNING
6158 		       "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6159 }
6160 
6161 static inline void unregister_as_ext2(void)
6162 {
6163 	unregister_filesystem(&ext2_fs_type);
6164 }
6165 
6166 static inline int ext2_feature_set_ok(struct super_block *sb)
6167 {
6168 	if (ext4_has_unknown_ext2_incompat_features(sb))
6169 		return 0;
6170 	if (sb_rdonly(sb))
6171 		return 1;
6172 	if (ext4_has_unknown_ext2_ro_compat_features(sb))
6173 		return 0;
6174 	return 1;
6175 }
6176 #else
6177 static inline void register_as_ext2(void) { }
6178 static inline void unregister_as_ext2(void) { }
6179 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6180 #endif
6181 
6182 static inline void register_as_ext3(void)
6183 {
6184 	int err = register_filesystem(&ext3_fs_type);
6185 	if (err)
6186 		printk(KERN_WARNING
6187 		       "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6188 }
6189 
6190 static inline void unregister_as_ext3(void)
6191 {
6192 	unregister_filesystem(&ext3_fs_type);
6193 }
6194 
6195 static inline int ext3_feature_set_ok(struct super_block *sb)
6196 {
6197 	if (ext4_has_unknown_ext3_incompat_features(sb))
6198 		return 0;
6199 	if (!ext4_has_feature_journal(sb))
6200 		return 0;
6201 	if (sb_rdonly(sb))
6202 		return 1;
6203 	if (ext4_has_unknown_ext3_ro_compat_features(sb))
6204 		return 0;
6205 	return 1;
6206 }
6207 
6208 static struct file_system_type ext4_fs_type = {
6209 	.owner		= THIS_MODULE,
6210 	.name		= "ext4",
6211 	.mount		= ext4_mount,
6212 	.kill_sb	= kill_block_super,
6213 	.fs_flags	= FS_REQUIRES_DEV,
6214 };
6215 MODULE_ALIAS_FS("ext4");
6216 
6217 /* Shared across all ext4 file systems */
6218 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6219 
6220 static int __init ext4_init_fs(void)
6221 {
6222 	int i, err;
6223 
6224 	ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6225 	ext4_li_info = NULL;
6226 	mutex_init(&ext4_li_mtx);
6227 
6228 	/* Build-time check for flags consistency */
6229 	ext4_check_flag_values();
6230 
6231 	for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6232 		init_waitqueue_head(&ext4__ioend_wq[i]);
6233 
6234 	err = ext4_init_es();
6235 	if (err)
6236 		return err;
6237 
6238 	err = ext4_init_pending();
6239 	if (err)
6240 		goto out7;
6241 
6242 	err = ext4_init_post_read_processing();
6243 	if (err)
6244 		goto out6;
6245 
6246 	err = ext4_init_pageio();
6247 	if (err)
6248 		goto out5;
6249 
6250 	err = ext4_init_system_zone();
6251 	if (err)
6252 		goto out4;
6253 
6254 	err = ext4_init_sysfs();
6255 	if (err)
6256 		goto out3;
6257 
6258 	err = ext4_init_mballoc();
6259 	if (err)
6260 		goto out2;
6261 	err = init_inodecache();
6262 	if (err)
6263 		goto out1;
6264 	register_as_ext3();
6265 	register_as_ext2();
6266 	err = register_filesystem(&ext4_fs_type);
6267 	if (err)
6268 		goto out;
6269 
6270 	return 0;
6271 out:
6272 	unregister_as_ext2();
6273 	unregister_as_ext3();
6274 	destroy_inodecache();
6275 out1:
6276 	ext4_exit_mballoc();
6277 out2:
6278 	ext4_exit_sysfs();
6279 out3:
6280 	ext4_exit_system_zone();
6281 out4:
6282 	ext4_exit_pageio();
6283 out5:
6284 	ext4_exit_post_read_processing();
6285 out6:
6286 	ext4_exit_pending();
6287 out7:
6288 	ext4_exit_es();
6289 
6290 	return err;
6291 }
6292 
6293 static void __exit ext4_exit_fs(void)
6294 {
6295 	ext4_destroy_lazyinit_thread();
6296 	unregister_as_ext2();
6297 	unregister_as_ext3();
6298 	unregister_filesystem(&ext4_fs_type);
6299 	destroy_inodecache();
6300 	ext4_exit_mballoc();
6301 	ext4_exit_sysfs();
6302 	ext4_exit_system_zone();
6303 	ext4_exit_pageio();
6304 	ext4_exit_post_read_processing();
6305 	ext4_exit_es();
6306 	ext4_exit_pending();
6307 }
6308 
6309 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6310 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6311 MODULE_LICENSE("GPL");
6312 MODULE_SOFTDEP("pre: crc32c");
6313 module_init(ext4_init_fs)
6314 module_exit(ext4_exit_fs)
6315