Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git...
[sfrench/cifs-2.6.git] / fs / ext4 / super.c
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
47 #include <linux/kthread.h>
48 #include <linux/freezer.h>
49
50 #include "ext4.h"
51 #include "ext4_extents.h"       /* Needed for trace points definition */
52 #include "ext4_jbd2.h"
53 #include "xattr.h"
54 #include "acl.h"
55 #include "mballoc.h"
56 #include "fsmap.h"
57
58 #define CREATE_TRACE_POINTS
59 #include <trace/events/ext4.h>
60
61 static struct ext4_lazy_init *ext4_li_info;
62 static struct mutex ext4_li_mtx;
63 static struct ratelimit_state ext4_mount_msg_ratelimit;
64
65 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
66                              unsigned long journal_devnum);
67 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
68 static int ext4_commit_super(struct super_block *sb, int sync);
69 static void ext4_mark_recovery_complete(struct super_block *sb,
70                                         struct ext4_super_block *es);
71 static void ext4_clear_journal_err(struct super_block *sb,
72                                    struct ext4_super_block *es);
73 static int ext4_sync_fs(struct super_block *sb, int wait);
74 static int ext4_remount(struct super_block *sb, int *flags, char *data);
75 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
76 static int ext4_unfreeze(struct super_block *sb);
77 static int ext4_freeze(struct super_block *sb);
78 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
79                        const char *dev_name, void *data);
80 static inline int ext2_feature_set_ok(struct super_block *sb);
81 static inline int ext3_feature_set_ok(struct super_block *sb);
82 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
83 static void ext4_destroy_lazyinit_thread(void);
84 static void ext4_unregister_li_request(struct super_block *sb);
85 static void ext4_clear_request_list(void);
86 static struct inode *ext4_get_journal_inode(struct super_block *sb,
87                                             unsigned int journal_inum);
88
89 /*
90  * Lock ordering
91  *
92  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
93  * i_mmap_rwsem (inode->i_mmap_rwsem)!
94  *
95  * page fault path:
96  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
97  *   page lock -> i_data_sem (rw)
98  *
99  * buffered write path:
100  * sb_start_write -> i_mutex -> mmap_sem
101  * sb_start_write -> i_mutex -> transaction start -> page lock ->
102  *   i_data_sem (rw)
103  *
104  * truncate:
105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
106  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
107  *   i_data_sem (rw)
108  *
109  * direct IO:
110  * sb_start_write -> i_mutex -> mmap_sem
111  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
112  *
113  * writepages:
114  * transaction start -> page lock(s) -> i_data_sem (rw)
115  */
116
117 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
118 static struct file_system_type ext2_fs_type = {
119         .owner          = THIS_MODULE,
120         .name           = "ext2",
121         .mount          = ext4_mount,
122         .kill_sb        = kill_block_super,
123         .fs_flags       = FS_REQUIRES_DEV,
124 };
125 MODULE_ALIAS_FS("ext2");
126 MODULE_ALIAS("ext2");
127 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
128 #else
129 #define IS_EXT2_SB(sb) (0)
130 #endif
131
132
133 static struct file_system_type ext3_fs_type = {
134         .owner          = THIS_MODULE,
135         .name           = "ext3",
136         .mount          = ext4_mount,
137         .kill_sb        = kill_block_super,
138         .fs_flags       = FS_REQUIRES_DEV,
139 };
140 MODULE_ALIAS_FS("ext3");
141 MODULE_ALIAS("ext3");
142 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
143
144 /*
145  * This works like sb_bread() except it uses ERR_PTR for error
146  * returns.  Currently with sb_bread it's impossible to distinguish
147  * between ENOMEM and EIO situations (since both result in a NULL
148  * return.
149  */
150 struct buffer_head *
151 ext4_sb_bread(struct super_block *sb, sector_t block, int op_flags)
152 {
153         struct buffer_head *bh = sb_getblk(sb, block);
154
155         if (bh == NULL)
156                 return ERR_PTR(-ENOMEM);
157         if (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 void *ext4_kvmalloc(size_t size, gfp_t flags)
208 {
209         void *ret;
210
211         ret = kmalloc(size, flags | __GFP_NOWARN);
212         if (!ret)
213                 ret = __vmalloc(size, flags, PAGE_KERNEL);
214         return ret;
215 }
216
217 void *ext4_kvzalloc(size_t size, gfp_t flags)
218 {
219         void *ret;
220
221         ret = kzalloc(size, flags | __GFP_NOWARN);
222         if (!ret)
223                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
224         return ret;
225 }
226
227 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
228                                struct ext4_group_desc *bg)
229 {
230         return le32_to_cpu(bg->bg_block_bitmap_lo) |
231                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
232                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
233 }
234
235 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
236                                struct ext4_group_desc *bg)
237 {
238         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
239                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
240                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
241 }
242
243 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
244                               struct ext4_group_desc *bg)
245 {
246         return le32_to_cpu(bg->bg_inode_table_lo) |
247                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
248                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
249 }
250
251 __u32 ext4_free_group_clusters(struct super_block *sb,
252                                struct ext4_group_desc *bg)
253 {
254         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
255                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
256                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
257 }
258
259 __u32 ext4_free_inodes_count(struct super_block *sb,
260                               struct ext4_group_desc *bg)
261 {
262         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
263                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
264                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
265 }
266
267 __u32 ext4_used_dirs_count(struct super_block *sb,
268                               struct ext4_group_desc *bg)
269 {
270         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
271                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
272                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
273 }
274
275 __u32 ext4_itable_unused_count(struct super_block *sb,
276                               struct ext4_group_desc *bg)
277 {
278         return le16_to_cpu(bg->bg_itable_unused_lo) |
279                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
280                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
281 }
282
283 void ext4_block_bitmap_set(struct super_block *sb,
284                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
285 {
286         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
287         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
288                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
289 }
290
291 void ext4_inode_bitmap_set(struct super_block *sb,
292                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
293 {
294         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
295         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
296                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
297 }
298
299 void ext4_inode_table_set(struct super_block *sb,
300                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
301 {
302         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
303         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
304                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
305 }
306
307 void ext4_free_group_clusters_set(struct super_block *sb,
308                                   struct ext4_group_desc *bg, __u32 count)
309 {
310         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
311         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
312                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
313 }
314
315 void ext4_free_inodes_set(struct super_block *sb,
316                           struct ext4_group_desc *bg, __u32 count)
317 {
318         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
319         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
320                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
321 }
322
323 void ext4_used_dirs_set(struct super_block *sb,
324                           struct ext4_group_desc *bg, __u32 count)
325 {
326         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
327         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
328                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
329 }
330
331 void ext4_itable_unused_set(struct super_block *sb,
332                           struct ext4_group_desc *bg, __u32 count)
333 {
334         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
335         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
336                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
337 }
338
339 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
340 {
341         time64_t now = ktime_get_real_seconds();
342
343         now = clamp_val(now, 0, (1ull << 40) - 1);
344
345         *lo = cpu_to_le32(lower_32_bits(now));
346         *hi = upper_32_bits(now);
347 }
348
349 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
350 {
351         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
352 }
353 #define ext4_update_tstamp(es, tstamp) \
354         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
355 #define ext4_get_tstamp(es, tstamp) \
356         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
357
358 static void __save_error_info(struct super_block *sb, const char *func,
359                             unsigned int line)
360 {
361         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
362
363         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
364         if (bdev_read_only(sb->s_bdev))
365                 return;
366         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
367         ext4_update_tstamp(es, s_last_error_time);
368         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
369         es->s_last_error_line = cpu_to_le32(line);
370         if (!es->s_first_error_time) {
371                 es->s_first_error_time = es->s_last_error_time;
372                 es->s_first_error_time_hi = es->s_last_error_time_hi;
373                 strncpy(es->s_first_error_func, func,
374                         sizeof(es->s_first_error_func));
375                 es->s_first_error_line = cpu_to_le32(line);
376                 es->s_first_error_ino = es->s_last_error_ino;
377                 es->s_first_error_block = es->s_last_error_block;
378         }
379         /*
380          * Start the daily error reporting function if it hasn't been
381          * started already
382          */
383         if (!es->s_error_count)
384                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
385         le32_add_cpu(&es->s_error_count, 1);
386 }
387
388 static void save_error_info(struct super_block *sb, const char *func,
389                             unsigned int line)
390 {
391         __save_error_info(sb, func, line);
392         ext4_commit_super(sb, 1);
393 }
394
395 /*
396  * The del_gendisk() function uninitializes the disk-specific data
397  * structures, including the bdi structure, without telling anyone
398  * else.  Once this happens, any attempt to call mark_buffer_dirty()
399  * (for example, by ext4_commit_super), will cause a kernel OOPS.
400  * This is a kludge to prevent these oops until we can put in a proper
401  * hook in del_gendisk() to inform the VFS and file system layers.
402  */
403 static int block_device_ejected(struct super_block *sb)
404 {
405         struct inode *bd_inode = sb->s_bdev->bd_inode;
406         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
407
408         return bdi->dev == NULL;
409 }
410
411 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
412 {
413         struct super_block              *sb = journal->j_private;
414         struct ext4_sb_info             *sbi = EXT4_SB(sb);
415         int                             error = is_journal_aborted(journal);
416         struct ext4_journal_cb_entry    *jce;
417
418         BUG_ON(txn->t_state == T_FINISHED);
419
420         ext4_process_freed_data(sb, txn->t_tid);
421
422         spin_lock(&sbi->s_md_lock);
423         while (!list_empty(&txn->t_private_list)) {
424                 jce = list_entry(txn->t_private_list.next,
425                                  struct ext4_journal_cb_entry, jce_list);
426                 list_del_init(&jce->jce_list);
427                 spin_unlock(&sbi->s_md_lock);
428                 jce->jce_func(sb, jce, error);
429                 spin_lock(&sbi->s_md_lock);
430         }
431         spin_unlock(&sbi->s_md_lock);
432 }
433
434 static bool system_going_down(void)
435 {
436         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
437                 || system_state == SYSTEM_RESTART;
438 }
439
440 /* Deal with the reporting of failure conditions on a filesystem such as
441  * inconsistencies detected or read IO failures.
442  *
443  * On ext2, we can store the error state of the filesystem in the
444  * superblock.  That is not possible on ext4, because we may have other
445  * write ordering constraints on the superblock which prevent us from
446  * writing it out straight away; and given that the journal is about to
447  * be aborted, we can't rely on the current, or future, transactions to
448  * write out the superblock safely.
449  *
450  * We'll just use the jbd2_journal_abort() error code to record an error in
451  * the journal instead.  On recovery, the journal will complain about
452  * that error until we've noted it down and cleared it.
453  */
454
455 static void ext4_handle_error(struct super_block *sb)
456 {
457         if (test_opt(sb, WARN_ON_ERROR))
458                 WARN_ON_ONCE(1);
459
460         if (sb_rdonly(sb))
461                 return;
462
463         if (!test_opt(sb, ERRORS_CONT)) {
464                 journal_t *journal = EXT4_SB(sb)->s_journal;
465
466                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
467                 if (journal)
468                         jbd2_journal_abort(journal, -EIO);
469         }
470         /*
471          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
472          * could panic during 'reboot -f' as the underlying device got already
473          * disabled.
474          */
475         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
476                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
477                 /*
478                  * Make sure updated value of ->s_mount_flags will be visible
479                  * before ->s_flags update
480                  */
481                 smp_wmb();
482                 sb->s_flags |= SB_RDONLY;
483         } else if (test_opt(sb, ERRORS_PANIC)) {
484                 if (EXT4_SB(sb)->s_journal &&
485                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
486                         return;
487                 panic("EXT4-fs (device %s): panic forced after error\n",
488                         sb->s_id);
489         }
490 }
491
492 #define ext4_error_ratelimit(sb)                                        \
493                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
494                              "EXT4-fs error")
495
496 void __ext4_error(struct super_block *sb, const char *function,
497                   unsigned int line, const char *fmt, ...)
498 {
499         struct va_format vaf;
500         va_list args;
501
502         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
503                 return;
504
505         trace_ext4_error(sb, function, line);
506         if (ext4_error_ratelimit(sb)) {
507                 va_start(args, fmt);
508                 vaf.fmt = fmt;
509                 vaf.va = &args;
510                 printk(KERN_CRIT
511                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
512                        sb->s_id, function, line, current->comm, &vaf);
513                 va_end(args);
514         }
515         save_error_info(sb, function, line);
516         ext4_handle_error(sb);
517 }
518
519 void __ext4_error_inode(struct inode *inode, const char *function,
520                         unsigned int line, ext4_fsblk_t block,
521                         const char *fmt, ...)
522 {
523         va_list args;
524         struct va_format vaf;
525         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
526
527         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
528                 return;
529
530         trace_ext4_error(inode->i_sb, function, line);
531         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
532         es->s_last_error_block = cpu_to_le64(block);
533         if (ext4_error_ratelimit(inode->i_sb)) {
534                 va_start(args, fmt);
535                 vaf.fmt = fmt;
536                 vaf.va = &args;
537                 if (block)
538                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
539                                "inode #%lu: block %llu: comm %s: %pV\n",
540                                inode->i_sb->s_id, function, line, inode->i_ino,
541                                block, current->comm, &vaf);
542                 else
543                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
544                                "inode #%lu: comm %s: %pV\n",
545                                inode->i_sb->s_id, function, line, inode->i_ino,
546                                current->comm, &vaf);
547                 va_end(args);
548         }
549         save_error_info(inode->i_sb, function, line);
550         ext4_handle_error(inode->i_sb);
551 }
552
553 void __ext4_error_file(struct file *file, const char *function,
554                        unsigned int line, ext4_fsblk_t block,
555                        const char *fmt, ...)
556 {
557         va_list args;
558         struct va_format vaf;
559         struct ext4_super_block *es;
560         struct inode *inode = file_inode(file);
561         char pathname[80], *path;
562
563         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
564                 return;
565
566         trace_ext4_error(inode->i_sb, function, line);
567         es = EXT4_SB(inode->i_sb)->s_es;
568         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
569         if (ext4_error_ratelimit(inode->i_sb)) {
570                 path = file_path(file, pathname, sizeof(pathname));
571                 if (IS_ERR(path))
572                         path = "(unknown)";
573                 va_start(args, fmt);
574                 vaf.fmt = fmt;
575                 vaf.va = &args;
576                 if (block)
577                         printk(KERN_CRIT
578                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
579                                "block %llu: comm %s: path %s: %pV\n",
580                                inode->i_sb->s_id, function, line, inode->i_ino,
581                                block, current->comm, path, &vaf);
582                 else
583                         printk(KERN_CRIT
584                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
585                                "comm %s: path %s: %pV\n",
586                                inode->i_sb->s_id, function, line, inode->i_ino,
587                                current->comm, path, &vaf);
588                 va_end(args);
589         }
590         save_error_info(inode->i_sb, function, line);
591         ext4_handle_error(inode->i_sb);
592 }
593
594 const char *ext4_decode_error(struct super_block *sb, int errno,
595                               char nbuf[16])
596 {
597         char *errstr = NULL;
598
599         switch (errno) {
600         case -EFSCORRUPTED:
601                 errstr = "Corrupt filesystem";
602                 break;
603         case -EFSBADCRC:
604                 errstr = "Filesystem failed CRC";
605                 break;
606         case -EIO:
607                 errstr = "IO failure";
608                 break;
609         case -ENOMEM:
610                 errstr = "Out of memory";
611                 break;
612         case -EROFS:
613                 if (!sb || (EXT4_SB(sb)->s_journal &&
614                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
615                         errstr = "Journal has aborted";
616                 else
617                         errstr = "Readonly filesystem";
618                 break;
619         default:
620                 /* If the caller passed in an extra buffer for unknown
621                  * errors, textualise them now.  Else we just return
622                  * NULL. */
623                 if (nbuf) {
624                         /* Check for truncated error codes... */
625                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
626                                 errstr = nbuf;
627                 }
628                 break;
629         }
630
631         return errstr;
632 }
633
634 /* __ext4_std_error decodes expected errors from journaling functions
635  * automatically and invokes the appropriate error response.  */
636
637 void __ext4_std_error(struct super_block *sb, const char *function,
638                       unsigned int line, int errno)
639 {
640         char nbuf[16];
641         const char *errstr;
642
643         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
644                 return;
645
646         /* Special case: if the error is EROFS, and we're not already
647          * inside a transaction, then there's really no point in logging
648          * an error. */
649         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
650                 return;
651
652         if (ext4_error_ratelimit(sb)) {
653                 errstr = ext4_decode_error(sb, errno, nbuf);
654                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
655                        sb->s_id, function, line, errstr);
656         }
657
658         save_error_info(sb, function, line);
659         ext4_handle_error(sb);
660 }
661
662 /*
663  * ext4_abort is a much stronger failure handler than ext4_error.  The
664  * abort function may be used to deal with unrecoverable failures such
665  * as journal IO errors or ENOMEM at a critical moment in log management.
666  *
667  * We unconditionally force the filesystem into an ABORT|READONLY state,
668  * unless the error response on the fs has been set to panic in which
669  * case we take the easy way out and panic immediately.
670  */
671
672 void __ext4_abort(struct super_block *sb, const char *function,
673                 unsigned int line, const char *fmt, ...)
674 {
675         struct va_format vaf;
676         va_list args;
677
678         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
679                 return;
680
681         save_error_info(sb, function, line);
682         va_start(args, fmt);
683         vaf.fmt = fmt;
684         vaf.va = &args;
685         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
686                sb->s_id, function, line, &vaf);
687         va_end(args);
688
689         if (sb_rdonly(sb) == 0) {
690                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
691                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
692                 /*
693                  * Make sure updated value of ->s_mount_flags will be visible
694                  * before ->s_flags update
695                  */
696                 smp_wmb();
697                 sb->s_flags |= SB_RDONLY;
698                 if (EXT4_SB(sb)->s_journal)
699                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
700                 save_error_info(sb, function, line);
701         }
702         if (test_opt(sb, ERRORS_PANIC) && !system_going_down()) {
703                 if (EXT4_SB(sb)->s_journal &&
704                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
705                         return;
706                 panic("EXT4-fs panic from previous error\n");
707         }
708 }
709
710 void __ext4_msg(struct super_block *sb,
711                 const char *prefix, const char *fmt, ...)
712 {
713         struct va_format vaf;
714         va_list args;
715
716         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
717                 return;
718
719         va_start(args, fmt);
720         vaf.fmt = fmt;
721         vaf.va = &args;
722         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
723         va_end(args);
724 }
725
726 #define ext4_warning_ratelimit(sb)                                      \
727                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
728                              "EXT4-fs warning")
729
730 void __ext4_warning(struct super_block *sb, const char *function,
731                     unsigned int line, const char *fmt, ...)
732 {
733         struct va_format vaf;
734         va_list args;
735
736         if (!ext4_warning_ratelimit(sb))
737                 return;
738
739         va_start(args, fmt);
740         vaf.fmt = fmt;
741         vaf.va = &args;
742         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
743                sb->s_id, function, line, &vaf);
744         va_end(args);
745 }
746
747 void __ext4_warning_inode(const struct inode *inode, const char *function,
748                           unsigned int line, const char *fmt, ...)
749 {
750         struct va_format vaf;
751         va_list args;
752
753         if (!ext4_warning_ratelimit(inode->i_sb))
754                 return;
755
756         va_start(args, fmt);
757         vaf.fmt = fmt;
758         vaf.va = &args;
759         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
760                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
761                function, line, inode->i_ino, current->comm, &vaf);
762         va_end(args);
763 }
764
765 void __ext4_grp_locked_error(const char *function, unsigned int line,
766                              struct super_block *sb, ext4_group_t grp,
767                              unsigned long ino, ext4_fsblk_t block,
768                              const char *fmt, ...)
769 __releases(bitlock)
770 __acquires(bitlock)
771 {
772         struct va_format vaf;
773         va_list args;
774         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
775
776         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
777                 return;
778
779         trace_ext4_error(sb, function, line);
780         es->s_last_error_ino = cpu_to_le32(ino);
781         es->s_last_error_block = cpu_to_le64(block);
782         __save_error_info(sb, function, line);
783
784         if (ext4_error_ratelimit(sb)) {
785                 va_start(args, fmt);
786                 vaf.fmt = fmt;
787                 vaf.va = &args;
788                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
789                        sb->s_id, function, line, grp);
790                 if (ino)
791                         printk(KERN_CONT "inode %lu: ", ino);
792                 if (block)
793                         printk(KERN_CONT "block %llu:",
794                                (unsigned long long) block);
795                 printk(KERN_CONT "%pV\n", &vaf);
796                 va_end(args);
797         }
798
799         if (test_opt(sb, WARN_ON_ERROR))
800                 WARN_ON_ONCE(1);
801
802         if (test_opt(sb, ERRORS_CONT)) {
803                 ext4_commit_super(sb, 0);
804                 return;
805         }
806
807         ext4_unlock_group(sb, grp);
808         ext4_commit_super(sb, 1);
809         ext4_handle_error(sb);
810         /*
811          * We only get here in the ERRORS_RO case; relocking the group
812          * may be dangerous, but nothing bad will happen since the
813          * filesystem will have already been marked read/only and the
814          * journal has been aborted.  We return 1 as a hint to callers
815          * who might what to use the return value from
816          * ext4_grp_locked_error() to distinguish between the
817          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
818          * aggressively from the ext4 function in question, with a
819          * more appropriate error code.
820          */
821         ext4_lock_group(sb, grp);
822         return;
823 }
824
825 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
826                                      ext4_group_t group,
827                                      unsigned int flags)
828 {
829         struct ext4_sb_info *sbi = EXT4_SB(sb);
830         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
831         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
832         int ret;
833
834         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
835                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
836                                             &grp->bb_state);
837                 if (!ret)
838                         percpu_counter_sub(&sbi->s_freeclusters_counter,
839                                            grp->bb_free);
840         }
841
842         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
843                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
844                                             &grp->bb_state);
845                 if (!ret && gdp) {
846                         int count;
847
848                         count = ext4_free_inodes_count(sb, gdp);
849                         percpu_counter_sub(&sbi->s_freeinodes_counter,
850                                            count);
851                 }
852         }
853 }
854
855 void ext4_update_dynamic_rev(struct super_block *sb)
856 {
857         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
858
859         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
860                 return;
861
862         ext4_warning(sb,
863                      "updating to rev %d because of new feature flag, "
864                      "running e2fsck is recommended",
865                      EXT4_DYNAMIC_REV);
866
867         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
868         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
869         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
870         /* leave es->s_feature_*compat flags alone */
871         /* es->s_uuid will be set by e2fsck if empty */
872
873         /*
874          * The rest of the superblock fields should be zero, and if not it
875          * means they are likely already in use, so leave them alone.  We
876          * can leave it up to e2fsck to clean up any inconsistencies there.
877          */
878 }
879
880 /*
881  * Open the external journal device
882  */
883 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
884 {
885         struct block_device *bdev;
886         char b[BDEVNAME_SIZE];
887
888         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
889         if (IS_ERR(bdev))
890                 goto fail;
891         return bdev;
892
893 fail:
894         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
895                         __bdevname(dev, b), PTR_ERR(bdev));
896         return NULL;
897 }
898
899 /*
900  * Release the journal device
901  */
902 static void ext4_blkdev_put(struct block_device *bdev)
903 {
904         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
905 }
906
907 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
908 {
909         struct block_device *bdev;
910         bdev = sbi->journal_bdev;
911         if (bdev) {
912                 ext4_blkdev_put(bdev);
913                 sbi->journal_bdev = NULL;
914         }
915 }
916
917 static inline struct inode *orphan_list_entry(struct list_head *l)
918 {
919         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
920 }
921
922 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
923 {
924         struct list_head *l;
925
926         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
927                  le32_to_cpu(sbi->s_es->s_last_orphan));
928
929         printk(KERN_ERR "sb_info orphan list:\n");
930         list_for_each(l, &sbi->s_orphan) {
931                 struct inode *inode = orphan_list_entry(l);
932                 printk(KERN_ERR "  "
933                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
934                        inode->i_sb->s_id, inode->i_ino, inode,
935                        inode->i_mode, inode->i_nlink,
936                        NEXT_ORPHAN(inode));
937         }
938 }
939
940 #ifdef CONFIG_QUOTA
941 static int ext4_quota_off(struct super_block *sb, int type);
942
943 static inline void ext4_quota_off_umount(struct super_block *sb)
944 {
945         int type;
946
947         /* Use our quota_off function to clear inode flags etc. */
948         for (type = 0; type < EXT4_MAXQUOTAS; type++)
949                 ext4_quota_off(sb, type);
950 }
951
952 /*
953  * This is a helper function which is used in the mount/remount
954  * codepaths (which holds s_umount) to fetch the quota file name.
955  */
956 static inline char *get_qf_name(struct super_block *sb,
957                                 struct ext4_sb_info *sbi,
958                                 int type)
959 {
960         return rcu_dereference_protected(sbi->s_qf_names[type],
961                                          lockdep_is_held(&sb->s_umount));
962 }
963 #else
964 static inline void ext4_quota_off_umount(struct super_block *sb)
965 {
966 }
967 #endif
968
969 static void ext4_put_super(struct super_block *sb)
970 {
971         struct ext4_sb_info *sbi = EXT4_SB(sb);
972         struct ext4_super_block *es = sbi->s_es;
973         int aborted = 0;
974         int i, err;
975
976         ext4_unregister_li_request(sb);
977         ext4_quota_off_umount(sb);
978
979         destroy_workqueue(sbi->rsv_conversion_wq);
980
981         if (sbi->s_journal) {
982                 aborted = is_journal_aborted(sbi->s_journal);
983                 err = jbd2_journal_destroy(sbi->s_journal);
984                 sbi->s_journal = NULL;
985                 if ((err < 0) && !aborted)
986                         ext4_abort(sb, "Couldn't clean up the journal");
987         }
988
989         ext4_unregister_sysfs(sb);
990         ext4_es_unregister_shrinker(sbi);
991         del_timer_sync(&sbi->s_err_report);
992         ext4_release_system_zone(sb);
993         ext4_mb_release(sb);
994         ext4_ext_release(sb);
995
996         if (!sb_rdonly(sb) && !aborted) {
997                 ext4_clear_feature_journal_needs_recovery(sb);
998                 es->s_state = cpu_to_le16(sbi->s_mount_state);
999         }
1000         if (!sb_rdonly(sb))
1001                 ext4_commit_super(sb, 1);
1002
1003         for (i = 0; i < sbi->s_gdb_count; i++)
1004                 brelse(sbi->s_group_desc[i]);
1005         kvfree(sbi->s_group_desc);
1006         kvfree(sbi->s_flex_groups);
1007         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1008         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1009         percpu_counter_destroy(&sbi->s_dirs_counter);
1010         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1011         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
1012 #ifdef CONFIG_QUOTA
1013         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1014                 kfree(get_qf_name(sb, sbi, i));
1015 #endif
1016
1017         /* Debugging code just in case the in-memory inode orphan list
1018          * isn't empty.  The on-disk one can be non-empty if we've
1019          * detected an error and taken the fs readonly, but the
1020          * in-memory list had better be clean by this point. */
1021         if (!list_empty(&sbi->s_orphan))
1022                 dump_orphan_list(sb, sbi);
1023         J_ASSERT(list_empty(&sbi->s_orphan));
1024
1025         sync_blockdev(sb->s_bdev);
1026         invalidate_bdev(sb->s_bdev);
1027         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
1028                 /*
1029                  * Invalidate the journal device's buffers.  We don't want them
1030                  * floating about in memory - the physical journal device may
1031                  * hotswapped, and it breaks the `ro-after' testing code.
1032                  */
1033                 sync_blockdev(sbi->journal_bdev);
1034                 invalidate_bdev(sbi->journal_bdev);
1035                 ext4_blkdev_remove(sbi);
1036         }
1037
1038         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1039         sbi->s_ea_inode_cache = NULL;
1040
1041         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1042         sbi->s_ea_block_cache = NULL;
1043
1044         if (sbi->s_mmp_tsk)
1045                 kthread_stop(sbi->s_mmp_tsk);
1046         brelse(sbi->s_sbh);
1047         sb->s_fs_info = NULL;
1048         /*
1049          * Now that we are completely done shutting down the
1050          * superblock, we need to actually destroy the kobject.
1051          */
1052         kobject_put(&sbi->s_kobj);
1053         wait_for_completion(&sbi->s_kobj_unregister);
1054         if (sbi->s_chksum_driver)
1055                 crypto_free_shash(sbi->s_chksum_driver);
1056         kfree(sbi->s_blockgroup_lock);
1057         fs_put_dax(sbi->s_daxdev);
1058 #ifdef CONFIG_UNICODE
1059         utf8_unload(sbi->s_encoding);
1060 #endif
1061         kfree(sbi);
1062 }
1063
1064 static struct kmem_cache *ext4_inode_cachep;
1065
1066 /*
1067  * Called inside transaction, so use GFP_NOFS
1068  */
1069 static struct inode *ext4_alloc_inode(struct super_block *sb)
1070 {
1071         struct ext4_inode_info *ei;
1072
1073         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1074         if (!ei)
1075                 return NULL;
1076
1077         inode_set_iversion(&ei->vfs_inode, 1);
1078         spin_lock_init(&ei->i_raw_lock);
1079         INIT_LIST_HEAD(&ei->i_prealloc_list);
1080         spin_lock_init(&ei->i_prealloc_lock);
1081         ext4_es_init_tree(&ei->i_es_tree);
1082         rwlock_init(&ei->i_es_lock);
1083         INIT_LIST_HEAD(&ei->i_es_list);
1084         ei->i_es_all_nr = 0;
1085         ei->i_es_shk_nr = 0;
1086         ei->i_es_shrink_lblk = 0;
1087         ei->i_reserved_data_blocks = 0;
1088         ei->i_da_metadata_calc_len = 0;
1089         ei->i_da_metadata_calc_last_lblock = 0;
1090         spin_lock_init(&(ei->i_block_reservation_lock));
1091         ext4_init_pending_tree(&ei->i_pending_tree);
1092 #ifdef CONFIG_QUOTA
1093         ei->i_reserved_quota = 0;
1094         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1095 #endif
1096         ei->jinode = NULL;
1097         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1098         spin_lock_init(&ei->i_completed_io_lock);
1099         ei->i_sync_tid = 0;
1100         ei->i_datasync_tid = 0;
1101         atomic_set(&ei->i_unwritten, 0);
1102         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1103         return &ei->vfs_inode;
1104 }
1105
1106 static int ext4_drop_inode(struct inode *inode)
1107 {
1108         int drop = generic_drop_inode(inode);
1109
1110         if (!drop)
1111                 drop = fscrypt_drop_inode(inode);
1112
1113         trace_ext4_drop_inode(inode, drop);
1114         return drop;
1115 }
1116
1117 static void ext4_free_in_core_inode(struct inode *inode)
1118 {
1119         fscrypt_free_inode(inode);
1120         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1121 }
1122
1123 static void ext4_destroy_inode(struct inode *inode)
1124 {
1125         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1126                 ext4_msg(inode->i_sb, KERN_ERR,
1127                          "Inode %lu (%p): orphan list check failed!",
1128                          inode->i_ino, EXT4_I(inode));
1129                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1130                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1131                                 true);
1132                 dump_stack();
1133         }
1134 }
1135
1136 static void init_once(void *foo)
1137 {
1138         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1139
1140         INIT_LIST_HEAD(&ei->i_orphan);
1141         init_rwsem(&ei->xattr_sem);
1142         init_rwsem(&ei->i_data_sem);
1143         init_rwsem(&ei->i_mmap_sem);
1144         inode_init_once(&ei->vfs_inode);
1145 }
1146
1147 static int __init init_inodecache(void)
1148 {
1149         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1150                                 sizeof(struct ext4_inode_info), 0,
1151                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1152                                         SLAB_ACCOUNT),
1153                                 offsetof(struct ext4_inode_info, i_data),
1154                                 sizeof_field(struct ext4_inode_info, i_data),
1155                                 init_once);
1156         if (ext4_inode_cachep == NULL)
1157                 return -ENOMEM;
1158         return 0;
1159 }
1160
1161 static void destroy_inodecache(void)
1162 {
1163         /*
1164          * Make sure all delayed rcu free inodes are flushed before we
1165          * destroy cache.
1166          */
1167         rcu_barrier();
1168         kmem_cache_destroy(ext4_inode_cachep);
1169 }
1170
1171 void ext4_clear_inode(struct inode *inode)
1172 {
1173         invalidate_inode_buffers(inode);
1174         clear_inode(inode);
1175         ext4_discard_preallocations(inode);
1176         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1177         dquot_drop(inode);
1178         if (EXT4_I(inode)->jinode) {
1179                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1180                                                EXT4_I(inode)->jinode);
1181                 jbd2_free_inode(EXT4_I(inode)->jinode);
1182                 EXT4_I(inode)->jinode = NULL;
1183         }
1184         fscrypt_put_encryption_info(inode);
1185         fsverity_cleanup_inode(inode);
1186 }
1187
1188 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1189                                         u64 ino, u32 generation)
1190 {
1191         struct inode *inode;
1192
1193         /*
1194          * Currently we don't know the generation for parent directory, so
1195          * a generation of 0 means "accept any"
1196          */
1197         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1198         if (IS_ERR(inode))
1199                 return ERR_CAST(inode);
1200         if (generation && inode->i_generation != generation) {
1201                 iput(inode);
1202                 return ERR_PTR(-ESTALE);
1203         }
1204
1205         return inode;
1206 }
1207
1208 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1209                                         int fh_len, int fh_type)
1210 {
1211         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1212                                     ext4_nfs_get_inode);
1213 }
1214
1215 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1216                                         int fh_len, int fh_type)
1217 {
1218         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1219                                     ext4_nfs_get_inode);
1220 }
1221
1222 static int ext4_nfs_commit_metadata(struct inode *inode)
1223 {
1224         struct writeback_control wbc = {
1225                 .sync_mode = WB_SYNC_ALL
1226         };
1227
1228         trace_ext4_nfs_commit_metadata(inode);
1229         return ext4_write_inode(inode, &wbc);
1230 }
1231
1232 /*
1233  * Try to release metadata pages (indirect blocks, directories) which are
1234  * mapped via the block device.  Since these pages could have journal heads
1235  * which would prevent try_to_free_buffers() from freeing them, we must use
1236  * jbd2 layer's try_to_free_buffers() function to release them.
1237  */
1238 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1239                                  gfp_t wait)
1240 {
1241         journal_t *journal = EXT4_SB(sb)->s_journal;
1242
1243         WARN_ON(PageChecked(page));
1244         if (!page_has_buffers(page))
1245                 return 0;
1246         if (journal)
1247                 return jbd2_journal_try_to_free_buffers(journal, page,
1248                                                 wait & ~__GFP_DIRECT_RECLAIM);
1249         return try_to_free_buffers(page);
1250 }
1251
1252 #ifdef CONFIG_FS_ENCRYPTION
1253 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1254 {
1255         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1256                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1257 }
1258
1259 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1260                                                         void *fs_data)
1261 {
1262         handle_t *handle = fs_data;
1263         int res, res2, credits, retries = 0;
1264
1265         /*
1266          * Encrypting the root directory is not allowed because e2fsck expects
1267          * lost+found to exist and be unencrypted, and encrypting the root
1268          * directory would imply encrypting the lost+found directory as well as
1269          * the filename "lost+found" itself.
1270          */
1271         if (inode->i_ino == EXT4_ROOT_INO)
1272                 return -EPERM;
1273
1274         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1275                 return -EINVAL;
1276
1277         res = ext4_convert_inline_data(inode);
1278         if (res)
1279                 return res;
1280
1281         /*
1282          * If a journal handle was specified, then the encryption context is
1283          * being set on a new inode via inheritance and is part of a larger
1284          * transaction to create the inode.  Otherwise the encryption context is
1285          * being set on an existing inode in its own transaction.  Only in the
1286          * latter case should the "retry on ENOSPC" logic be used.
1287          */
1288
1289         if (handle) {
1290                 res = ext4_xattr_set_handle(handle, inode,
1291                                             EXT4_XATTR_INDEX_ENCRYPTION,
1292                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1293                                             ctx, len, 0);
1294                 if (!res) {
1295                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1296                         ext4_clear_inode_state(inode,
1297                                         EXT4_STATE_MAY_INLINE_DATA);
1298                         /*
1299                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1300                          * S_DAX may be disabled
1301                          */
1302                         ext4_set_inode_flags(inode);
1303                 }
1304                 return res;
1305         }
1306
1307         res = dquot_initialize(inode);
1308         if (res)
1309                 return res;
1310 retry:
1311         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1312                                      &credits);
1313         if (res)
1314                 return res;
1315
1316         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1317         if (IS_ERR(handle))
1318                 return PTR_ERR(handle);
1319
1320         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1321                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1322                                     ctx, len, 0);
1323         if (!res) {
1324                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1325                 /*
1326                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1327                  * S_DAX may be disabled
1328                  */
1329                 ext4_set_inode_flags(inode);
1330                 res = ext4_mark_inode_dirty(handle, inode);
1331                 if (res)
1332                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1333         }
1334         res2 = ext4_journal_stop(handle);
1335
1336         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1337                 goto retry;
1338         if (!res)
1339                 res = res2;
1340         return res;
1341 }
1342
1343 static bool ext4_dummy_context(struct inode *inode)
1344 {
1345         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1346 }
1347
1348 static bool ext4_has_stable_inodes(struct super_block *sb)
1349 {
1350         return ext4_has_feature_stable_inodes(sb);
1351 }
1352
1353 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1354                                        int *ino_bits_ret, int *lblk_bits_ret)
1355 {
1356         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1357         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1358 }
1359
1360 static const struct fscrypt_operations ext4_cryptops = {
1361         .key_prefix             = "ext4:",
1362         .get_context            = ext4_get_context,
1363         .set_context            = ext4_set_context,
1364         .dummy_context          = ext4_dummy_context,
1365         .empty_dir              = ext4_empty_dir,
1366         .max_namelen            = EXT4_NAME_LEN,
1367         .has_stable_inodes      = ext4_has_stable_inodes,
1368         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1369 };
1370 #endif
1371
1372 #ifdef CONFIG_QUOTA
1373 static const char * const quotatypes[] = INITQFNAMES;
1374 #define QTYPE2NAME(t) (quotatypes[t])
1375
1376 static int ext4_write_dquot(struct dquot *dquot);
1377 static int ext4_acquire_dquot(struct dquot *dquot);
1378 static int ext4_release_dquot(struct dquot *dquot);
1379 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1380 static int ext4_write_info(struct super_block *sb, int type);
1381 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1382                          const struct path *path);
1383 static int ext4_quota_on_mount(struct super_block *sb, int type);
1384 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1385                                size_t len, loff_t off);
1386 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1387                                 const char *data, size_t len, loff_t off);
1388 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1389                              unsigned int flags);
1390 static int ext4_enable_quotas(struct super_block *sb);
1391
1392 static struct dquot **ext4_get_dquots(struct inode *inode)
1393 {
1394         return EXT4_I(inode)->i_dquot;
1395 }
1396
1397 static const struct dquot_operations ext4_quota_operations = {
1398         .get_reserved_space     = ext4_get_reserved_space,
1399         .write_dquot            = ext4_write_dquot,
1400         .acquire_dquot          = ext4_acquire_dquot,
1401         .release_dquot          = ext4_release_dquot,
1402         .mark_dirty             = ext4_mark_dquot_dirty,
1403         .write_info             = ext4_write_info,
1404         .alloc_dquot            = dquot_alloc,
1405         .destroy_dquot          = dquot_destroy,
1406         .get_projid             = ext4_get_projid,
1407         .get_inode_usage        = ext4_get_inode_usage,
1408         .get_next_id            = dquot_get_next_id,
1409 };
1410
1411 static const struct quotactl_ops ext4_qctl_operations = {
1412         .quota_on       = ext4_quota_on,
1413         .quota_off      = ext4_quota_off,
1414         .quota_sync     = dquot_quota_sync,
1415         .get_state      = dquot_get_state,
1416         .set_info       = dquot_set_dqinfo,
1417         .get_dqblk      = dquot_get_dqblk,
1418         .set_dqblk      = dquot_set_dqblk,
1419         .get_nextdqblk  = dquot_get_next_dqblk,
1420 };
1421 #endif
1422
1423 static const struct super_operations ext4_sops = {
1424         .alloc_inode    = ext4_alloc_inode,
1425         .free_inode     = ext4_free_in_core_inode,
1426         .destroy_inode  = ext4_destroy_inode,
1427         .write_inode    = ext4_write_inode,
1428         .dirty_inode    = ext4_dirty_inode,
1429         .drop_inode     = ext4_drop_inode,
1430         .evict_inode    = ext4_evict_inode,
1431         .put_super      = ext4_put_super,
1432         .sync_fs        = ext4_sync_fs,
1433         .freeze_fs      = ext4_freeze,
1434         .unfreeze_fs    = ext4_unfreeze,
1435         .statfs         = ext4_statfs,
1436         .remount_fs     = ext4_remount,
1437         .show_options   = ext4_show_options,
1438 #ifdef CONFIG_QUOTA
1439         .quota_read     = ext4_quota_read,
1440         .quota_write    = ext4_quota_write,
1441         .get_dquots     = ext4_get_dquots,
1442 #endif
1443         .bdev_try_to_free_page = bdev_try_to_free_page,
1444 };
1445
1446 static const struct export_operations ext4_export_ops = {
1447         .fh_to_dentry = ext4_fh_to_dentry,
1448         .fh_to_parent = ext4_fh_to_parent,
1449         .get_parent = ext4_get_parent,
1450         .commit_metadata = ext4_nfs_commit_metadata,
1451 };
1452
1453 enum {
1454         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1455         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1456         Opt_nouid32, Opt_debug, Opt_removed,
1457         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1458         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1459         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1460         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1461         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1462         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1463         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1464         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1465         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1466         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1467         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1468         Opt_nowarn_on_error, Opt_mblk_io_submit,
1469         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1470         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1471         Opt_inode_readahead_blks, Opt_journal_ioprio,
1472         Opt_dioread_nolock, Opt_dioread_lock,
1473         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1474         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1475 };
1476
1477 static const match_table_t tokens = {
1478         {Opt_bsd_df, "bsddf"},
1479         {Opt_minix_df, "minixdf"},
1480         {Opt_grpid, "grpid"},
1481         {Opt_grpid, "bsdgroups"},
1482         {Opt_nogrpid, "nogrpid"},
1483         {Opt_nogrpid, "sysvgroups"},
1484         {Opt_resgid, "resgid=%u"},
1485         {Opt_resuid, "resuid=%u"},
1486         {Opt_sb, "sb=%u"},
1487         {Opt_err_cont, "errors=continue"},
1488         {Opt_err_panic, "errors=panic"},
1489         {Opt_err_ro, "errors=remount-ro"},
1490         {Opt_nouid32, "nouid32"},
1491         {Opt_debug, "debug"},
1492         {Opt_removed, "oldalloc"},
1493         {Opt_removed, "orlov"},
1494         {Opt_user_xattr, "user_xattr"},
1495         {Opt_nouser_xattr, "nouser_xattr"},
1496         {Opt_acl, "acl"},
1497         {Opt_noacl, "noacl"},
1498         {Opt_noload, "norecovery"},
1499         {Opt_noload, "noload"},
1500         {Opt_removed, "nobh"},
1501         {Opt_removed, "bh"},
1502         {Opt_commit, "commit=%u"},
1503         {Opt_min_batch_time, "min_batch_time=%u"},
1504         {Opt_max_batch_time, "max_batch_time=%u"},
1505         {Opt_journal_dev, "journal_dev=%u"},
1506         {Opt_journal_path, "journal_path=%s"},
1507         {Opt_journal_checksum, "journal_checksum"},
1508         {Opt_nojournal_checksum, "nojournal_checksum"},
1509         {Opt_journal_async_commit, "journal_async_commit"},
1510         {Opt_abort, "abort"},
1511         {Opt_data_journal, "data=journal"},
1512         {Opt_data_ordered, "data=ordered"},
1513         {Opt_data_writeback, "data=writeback"},
1514         {Opt_data_err_abort, "data_err=abort"},
1515         {Opt_data_err_ignore, "data_err=ignore"},
1516         {Opt_offusrjquota, "usrjquota="},
1517         {Opt_usrjquota, "usrjquota=%s"},
1518         {Opt_offgrpjquota, "grpjquota="},
1519         {Opt_grpjquota, "grpjquota=%s"},
1520         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1521         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1522         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1523         {Opt_grpquota, "grpquota"},
1524         {Opt_noquota, "noquota"},
1525         {Opt_quota, "quota"},
1526         {Opt_usrquota, "usrquota"},
1527         {Opt_prjquota, "prjquota"},
1528         {Opt_barrier, "barrier=%u"},
1529         {Opt_barrier, "barrier"},
1530         {Opt_nobarrier, "nobarrier"},
1531         {Opt_i_version, "i_version"},
1532         {Opt_dax, "dax"},
1533         {Opt_stripe, "stripe=%u"},
1534         {Opt_delalloc, "delalloc"},
1535         {Opt_warn_on_error, "warn_on_error"},
1536         {Opt_nowarn_on_error, "nowarn_on_error"},
1537         {Opt_lazytime, "lazytime"},
1538         {Opt_nolazytime, "nolazytime"},
1539         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1540         {Opt_nodelalloc, "nodelalloc"},
1541         {Opt_removed, "mblk_io_submit"},
1542         {Opt_removed, "nomblk_io_submit"},
1543         {Opt_block_validity, "block_validity"},
1544         {Opt_noblock_validity, "noblock_validity"},
1545         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1546         {Opt_journal_ioprio, "journal_ioprio=%u"},
1547         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1548         {Opt_auto_da_alloc, "auto_da_alloc"},
1549         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1550         {Opt_dioread_nolock, "dioread_nolock"},
1551         {Opt_dioread_lock, "dioread_lock"},
1552         {Opt_discard, "discard"},
1553         {Opt_nodiscard, "nodiscard"},
1554         {Opt_init_itable, "init_itable=%u"},
1555         {Opt_init_itable, "init_itable"},
1556         {Opt_noinit_itable, "noinit_itable"},
1557         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1558         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1559         {Opt_nombcache, "nombcache"},
1560         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1561         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1562         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1563         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1564         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1565         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1566         {Opt_err, NULL},
1567 };
1568
1569 static ext4_fsblk_t get_sb_block(void **data)
1570 {
1571         ext4_fsblk_t    sb_block;
1572         char            *options = (char *) *data;
1573
1574         if (!options || strncmp(options, "sb=", 3) != 0)
1575                 return 1;       /* Default location */
1576
1577         options += 3;
1578         /* TODO: use simple_strtoll with >32bit ext4 */
1579         sb_block = simple_strtoul(options, &options, 0);
1580         if (*options && *options != ',') {
1581                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1582                        (char *) *data);
1583                 return 1;
1584         }
1585         if (*options == ',')
1586                 options++;
1587         *data = (void *) options;
1588
1589         return sb_block;
1590 }
1591
1592 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1593 static const char deprecated_msg[] =
1594         "Mount option \"%s\" will be removed by %s\n"
1595         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1596
1597 #ifdef CONFIG_QUOTA
1598 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1599 {
1600         struct ext4_sb_info *sbi = EXT4_SB(sb);
1601         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1602         int ret = -1;
1603
1604         if (sb_any_quota_loaded(sb) && !old_qname) {
1605                 ext4_msg(sb, KERN_ERR,
1606                         "Cannot change journaled "
1607                         "quota options when quota turned on");
1608                 return -1;
1609         }
1610         if (ext4_has_feature_quota(sb)) {
1611                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1612                          "ignored when QUOTA feature is enabled");
1613                 return 1;
1614         }
1615         qname = match_strdup(args);
1616         if (!qname) {
1617                 ext4_msg(sb, KERN_ERR,
1618                         "Not enough memory for storing quotafile name");
1619                 return -1;
1620         }
1621         if (old_qname) {
1622                 if (strcmp(old_qname, qname) == 0)
1623                         ret = 1;
1624                 else
1625                         ext4_msg(sb, KERN_ERR,
1626                                  "%s quota file already specified",
1627                                  QTYPE2NAME(qtype));
1628                 goto errout;
1629         }
1630         if (strchr(qname, '/')) {
1631                 ext4_msg(sb, KERN_ERR,
1632                         "quotafile must be on filesystem root");
1633                 goto errout;
1634         }
1635         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1636         set_opt(sb, QUOTA);
1637         return 1;
1638 errout:
1639         kfree(qname);
1640         return ret;
1641 }
1642
1643 static int clear_qf_name(struct super_block *sb, int qtype)
1644 {
1645
1646         struct ext4_sb_info *sbi = EXT4_SB(sb);
1647         char *old_qname = get_qf_name(sb, sbi, qtype);
1648
1649         if (sb_any_quota_loaded(sb) && old_qname) {
1650                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1651                         " when quota turned on");
1652                 return -1;
1653         }
1654         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1655         synchronize_rcu();
1656         kfree(old_qname);
1657         return 1;
1658 }
1659 #endif
1660
1661 #define MOPT_SET        0x0001
1662 #define MOPT_CLEAR      0x0002
1663 #define MOPT_NOSUPPORT  0x0004
1664 #define MOPT_EXPLICIT   0x0008
1665 #define MOPT_CLEAR_ERR  0x0010
1666 #define MOPT_GTE0       0x0020
1667 #ifdef CONFIG_QUOTA
1668 #define MOPT_Q          0
1669 #define MOPT_QFMT       0x0040
1670 #else
1671 #define MOPT_Q          MOPT_NOSUPPORT
1672 #define MOPT_QFMT       MOPT_NOSUPPORT
1673 #endif
1674 #define MOPT_DATAJ      0x0080
1675 #define MOPT_NO_EXT2    0x0100
1676 #define MOPT_NO_EXT3    0x0200
1677 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1678 #define MOPT_STRING     0x0400
1679
1680 static const struct mount_opts {
1681         int     token;
1682         int     mount_opt;
1683         int     flags;
1684 } ext4_mount_opts[] = {
1685         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1686         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1687         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1688         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1689         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1690         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1691         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1692          MOPT_EXT4_ONLY | MOPT_SET},
1693         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1694          MOPT_EXT4_ONLY | MOPT_CLEAR},
1695         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1696         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1697         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1698          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1699         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1700          MOPT_EXT4_ONLY | MOPT_CLEAR},
1701         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1702         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1703         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1704          MOPT_EXT4_ONLY | MOPT_CLEAR},
1705         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1706          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1707         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1708                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1709          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1710         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1711         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1712         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1713         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1714         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1715          MOPT_NO_EXT2},
1716         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1717          MOPT_NO_EXT2},
1718         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1719         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1720         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1721         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1722         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1723         {Opt_commit, 0, MOPT_GTE0},
1724         {Opt_max_batch_time, 0, MOPT_GTE0},
1725         {Opt_min_batch_time, 0, MOPT_GTE0},
1726         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1727         {Opt_init_itable, 0, MOPT_GTE0},
1728         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1729         {Opt_stripe, 0, MOPT_GTE0},
1730         {Opt_resuid, 0, MOPT_GTE0},
1731         {Opt_resgid, 0, MOPT_GTE0},
1732         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1733         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1734         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1735         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1736         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1737         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1738          MOPT_NO_EXT2 | MOPT_DATAJ},
1739         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1740         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1741 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1742         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1743         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1744 #else
1745         {Opt_acl, 0, MOPT_NOSUPPORT},
1746         {Opt_noacl, 0, MOPT_NOSUPPORT},
1747 #endif
1748         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1749         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1750         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1751         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1752         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1753                                                         MOPT_SET | MOPT_Q},
1754         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1755                                                         MOPT_SET | MOPT_Q},
1756         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1757                                                         MOPT_SET | MOPT_Q},
1758         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1759                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1760                                                         MOPT_CLEAR | MOPT_Q},
1761         {Opt_usrjquota, 0, MOPT_Q},
1762         {Opt_grpjquota, 0, MOPT_Q},
1763         {Opt_offusrjquota, 0, MOPT_Q},
1764         {Opt_offgrpjquota, 0, MOPT_Q},
1765         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1766         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1767         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1768         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1769         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1770         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1771         {Opt_err, 0, 0}
1772 };
1773
1774 #ifdef CONFIG_UNICODE
1775 static const struct ext4_sb_encodings {
1776         __u16 magic;
1777         char *name;
1778         char *version;
1779 } ext4_sb_encoding_map[] = {
1780         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
1781 };
1782
1783 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
1784                                  const struct ext4_sb_encodings **encoding,
1785                                  __u16 *flags)
1786 {
1787         __u16 magic = le16_to_cpu(es->s_encoding);
1788         int i;
1789
1790         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
1791                 if (magic == ext4_sb_encoding_map[i].magic)
1792                         break;
1793
1794         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
1795                 return -EINVAL;
1796
1797         *encoding = &ext4_sb_encoding_map[i];
1798         *flags = le16_to_cpu(es->s_encoding_flags);
1799
1800         return 0;
1801 }
1802 #endif
1803
1804 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1805                             substring_t *args, unsigned long *journal_devnum,
1806                             unsigned int *journal_ioprio, int is_remount)
1807 {
1808         struct ext4_sb_info *sbi = EXT4_SB(sb);
1809         const struct mount_opts *m;
1810         kuid_t uid;
1811         kgid_t gid;
1812         int arg = 0;
1813
1814 #ifdef CONFIG_QUOTA
1815         if (token == Opt_usrjquota)
1816                 return set_qf_name(sb, USRQUOTA, &args[0]);
1817         else if (token == Opt_grpjquota)
1818                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1819         else if (token == Opt_offusrjquota)
1820                 return clear_qf_name(sb, USRQUOTA);
1821         else if (token == Opt_offgrpjquota)
1822                 return clear_qf_name(sb, GRPQUOTA);
1823 #endif
1824         switch (token) {
1825         case Opt_noacl:
1826         case Opt_nouser_xattr:
1827                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1828                 break;
1829         case Opt_sb:
1830                 return 1;       /* handled by get_sb_block() */
1831         case Opt_removed:
1832                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1833                 return 1;
1834         case Opt_abort:
1835                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1836                 return 1;
1837         case Opt_i_version:
1838                 sb->s_flags |= SB_I_VERSION;
1839                 return 1;
1840         case Opt_lazytime:
1841                 sb->s_flags |= SB_LAZYTIME;
1842                 return 1;
1843         case Opt_nolazytime:
1844                 sb->s_flags &= ~SB_LAZYTIME;
1845                 return 1;
1846         }
1847
1848         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1849                 if (token == m->token)
1850                         break;
1851
1852         if (m->token == Opt_err) {
1853                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1854                          "or missing value", opt);
1855                 return -1;
1856         }
1857
1858         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1859                 ext4_msg(sb, KERN_ERR,
1860                          "Mount option \"%s\" incompatible with ext2", opt);
1861                 return -1;
1862         }
1863         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1864                 ext4_msg(sb, KERN_ERR,
1865                          "Mount option \"%s\" incompatible with ext3", opt);
1866                 return -1;
1867         }
1868
1869         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1870                 return -1;
1871         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1872                 return -1;
1873         if (m->flags & MOPT_EXPLICIT) {
1874                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1875                         set_opt2(sb, EXPLICIT_DELALLOC);
1876                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1877                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1878                 } else
1879                         return -1;
1880         }
1881         if (m->flags & MOPT_CLEAR_ERR)
1882                 clear_opt(sb, ERRORS_MASK);
1883         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1884                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1885                          "options when quota turned on");
1886                 return -1;
1887         }
1888
1889         if (m->flags & MOPT_NOSUPPORT) {
1890                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1891         } else if (token == Opt_commit) {
1892                 if (arg == 0)
1893                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1894                 else if (arg > INT_MAX / HZ) {
1895                         ext4_msg(sb, KERN_ERR,
1896                                  "Invalid commit interval %d, "
1897                                  "must be smaller than %d",
1898                                  arg, INT_MAX / HZ);
1899                         return -1;
1900                 }
1901                 sbi->s_commit_interval = HZ * arg;
1902         } else if (token == Opt_debug_want_extra_isize) {
1903                 if ((arg & 1) ||
1904                     (arg < 4) ||
1905                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
1906                         ext4_msg(sb, KERN_ERR,
1907                                  "Invalid want_extra_isize %d", arg);
1908                         return -1;
1909                 }
1910                 sbi->s_want_extra_isize = arg;
1911         } else if (token == Opt_max_batch_time) {
1912                 sbi->s_max_batch_time = arg;
1913         } else if (token == Opt_min_batch_time) {
1914                 sbi->s_min_batch_time = arg;
1915         } else if (token == Opt_inode_readahead_blks) {
1916                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1917                         ext4_msg(sb, KERN_ERR,
1918                                  "EXT4-fs: inode_readahead_blks must be "
1919                                  "0 or a power of 2 smaller than 2^31");
1920                         return -1;
1921                 }
1922                 sbi->s_inode_readahead_blks = arg;
1923         } else if (token == Opt_init_itable) {
1924                 set_opt(sb, INIT_INODE_TABLE);
1925                 if (!args->from)
1926                         arg = EXT4_DEF_LI_WAIT_MULT;
1927                 sbi->s_li_wait_mult = arg;
1928         } else if (token == Opt_max_dir_size_kb) {
1929                 sbi->s_max_dir_size_kb = arg;
1930         } else if (token == Opt_stripe) {
1931                 sbi->s_stripe = arg;
1932         } else if (token == Opt_resuid) {
1933                 uid = make_kuid(current_user_ns(), arg);
1934                 if (!uid_valid(uid)) {
1935                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1936                         return -1;
1937                 }
1938                 sbi->s_resuid = uid;
1939         } else if (token == Opt_resgid) {
1940                 gid = make_kgid(current_user_ns(), arg);
1941                 if (!gid_valid(gid)) {
1942                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1943                         return -1;
1944                 }
1945                 sbi->s_resgid = gid;
1946         } else if (token == Opt_journal_dev) {
1947                 if (is_remount) {
1948                         ext4_msg(sb, KERN_ERR,
1949                                  "Cannot specify journal on remount");
1950                         return -1;
1951                 }
1952                 *journal_devnum = arg;
1953         } else if (token == Opt_journal_path) {
1954                 char *journal_path;
1955                 struct inode *journal_inode;
1956                 struct path path;
1957                 int error;
1958
1959                 if (is_remount) {
1960                         ext4_msg(sb, KERN_ERR,
1961                                  "Cannot specify journal on remount");
1962                         return -1;
1963                 }
1964                 journal_path = match_strdup(&args[0]);
1965                 if (!journal_path) {
1966                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1967                                 "journal device string");
1968                         return -1;
1969                 }
1970
1971                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1972                 if (error) {
1973                         ext4_msg(sb, KERN_ERR, "error: could not find "
1974                                 "journal device path: error %d", error);
1975                         kfree(journal_path);
1976                         return -1;
1977                 }
1978
1979                 journal_inode = d_inode(path.dentry);
1980                 if (!S_ISBLK(journal_inode->i_mode)) {
1981                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1982                                 "is not a block device", journal_path);
1983                         path_put(&path);
1984                         kfree(journal_path);
1985                         return -1;
1986                 }
1987
1988                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1989                 path_put(&path);
1990                 kfree(journal_path);
1991         } else if (token == Opt_journal_ioprio) {
1992                 if (arg > 7) {
1993                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1994                                  " (must be 0-7)");
1995                         return -1;
1996                 }
1997                 *journal_ioprio =
1998                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1999         } else if (token == Opt_test_dummy_encryption) {
2000 #ifdef CONFIG_FS_ENCRYPTION
2001                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
2002                 ext4_msg(sb, KERN_WARNING,
2003                          "Test dummy encryption mode enabled");
2004 #else
2005                 ext4_msg(sb, KERN_WARNING,
2006                          "Test dummy encryption mount option ignored");
2007 #endif
2008         } else if (m->flags & MOPT_DATAJ) {
2009                 if (is_remount) {
2010                         if (!sbi->s_journal)
2011                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2012                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2013                                 ext4_msg(sb, KERN_ERR,
2014                                          "Cannot change data mode on remount");
2015                                 return -1;
2016                         }
2017                 } else {
2018                         clear_opt(sb, DATA_FLAGS);
2019                         sbi->s_mount_opt |= m->mount_opt;
2020                 }
2021 #ifdef CONFIG_QUOTA
2022         } else if (m->flags & MOPT_QFMT) {
2023                 if (sb_any_quota_loaded(sb) &&
2024                     sbi->s_jquota_fmt != m->mount_opt) {
2025                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2026                                  "quota options when quota turned on");
2027                         return -1;
2028                 }
2029                 if (ext4_has_feature_quota(sb)) {
2030                         ext4_msg(sb, KERN_INFO,
2031                                  "Quota format mount options ignored "
2032                                  "when QUOTA feature is enabled");
2033                         return 1;
2034                 }
2035                 sbi->s_jquota_fmt = m->mount_opt;
2036 #endif
2037         } else if (token == Opt_dax) {
2038 #ifdef CONFIG_FS_DAX
2039                 ext4_msg(sb, KERN_WARNING,
2040                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2041                 sbi->s_mount_opt |= m->mount_opt;
2042 #else
2043                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2044                 return -1;
2045 #endif
2046         } else if (token == Opt_data_err_abort) {
2047                 sbi->s_mount_opt |= m->mount_opt;
2048         } else if (token == Opt_data_err_ignore) {
2049                 sbi->s_mount_opt &= ~m->mount_opt;
2050         } else {
2051                 if (!args->from)
2052                         arg = 1;
2053                 if (m->flags & MOPT_CLEAR)
2054                         arg = !arg;
2055                 else if (unlikely(!(m->flags & MOPT_SET))) {
2056                         ext4_msg(sb, KERN_WARNING,
2057                                  "buggy handling of option %s", opt);
2058                         WARN_ON(1);
2059                         return -1;
2060                 }
2061                 if (arg != 0)
2062                         sbi->s_mount_opt |= m->mount_opt;
2063                 else
2064                         sbi->s_mount_opt &= ~m->mount_opt;
2065         }
2066         return 1;
2067 }
2068
2069 static int parse_options(char *options, struct super_block *sb,
2070                          unsigned long *journal_devnum,
2071                          unsigned int *journal_ioprio,
2072                          int is_remount)
2073 {
2074         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2075         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2076         substring_t args[MAX_OPT_ARGS];
2077         int token;
2078
2079         if (!options)
2080                 return 1;
2081
2082         while ((p = strsep(&options, ",")) != NULL) {
2083                 if (!*p)
2084                         continue;
2085                 /*
2086                  * Initialize args struct so we know whether arg was
2087                  * found; some options take optional arguments.
2088                  */
2089                 args[0].to = args[0].from = NULL;
2090                 token = match_token(p, tokens, args);
2091                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2092                                      journal_ioprio, is_remount) < 0)
2093                         return 0;
2094         }
2095 #ifdef CONFIG_QUOTA
2096         /*
2097          * We do the test below only for project quotas. 'usrquota' and
2098          * 'grpquota' mount options are allowed even without quota feature
2099          * to support legacy quotas in quota files.
2100          */
2101         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2102                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2103                          "Cannot enable project quota enforcement.");
2104                 return 0;
2105         }
2106         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2107         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2108         if (usr_qf_name || grp_qf_name) {
2109                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2110                         clear_opt(sb, USRQUOTA);
2111
2112                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2113                         clear_opt(sb, GRPQUOTA);
2114
2115                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2116                         ext4_msg(sb, KERN_ERR, "old and new quota "
2117                                         "format mixing");
2118                         return 0;
2119                 }
2120
2121                 if (!sbi->s_jquota_fmt) {
2122                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2123                                         "not specified");
2124                         return 0;
2125                 }
2126         }
2127 #endif
2128         return 1;
2129 }
2130
2131 static inline void ext4_show_quota_options(struct seq_file *seq,
2132                                            struct super_block *sb)
2133 {
2134 #if defined(CONFIG_QUOTA)
2135         struct ext4_sb_info *sbi = EXT4_SB(sb);
2136         char *usr_qf_name, *grp_qf_name;
2137
2138         if (sbi->s_jquota_fmt) {
2139                 char *fmtname = "";
2140
2141                 switch (sbi->s_jquota_fmt) {
2142                 case QFMT_VFS_OLD:
2143                         fmtname = "vfsold";
2144                         break;
2145                 case QFMT_VFS_V0:
2146                         fmtname = "vfsv0";
2147                         break;
2148                 case QFMT_VFS_V1:
2149                         fmtname = "vfsv1";
2150                         break;
2151                 }
2152                 seq_printf(seq, ",jqfmt=%s", fmtname);
2153         }
2154
2155         rcu_read_lock();
2156         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2157         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2158         if (usr_qf_name)
2159                 seq_show_option(seq, "usrjquota", usr_qf_name);
2160         if (grp_qf_name)
2161                 seq_show_option(seq, "grpjquota", grp_qf_name);
2162         rcu_read_unlock();
2163 #endif
2164 }
2165
2166 static const char *token2str(int token)
2167 {
2168         const struct match_token *t;
2169
2170         for (t = tokens; t->token != Opt_err; t++)
2171                 if (t->token == token && !strchr(t->pattern, '='))
2172                         break;
2173         return t->pattern;
2174 }
2175
2176 /*
2177  * Show an option if
2178  *  - it's set to a non-default value OR
2179  *  - if the per-sb default is different from the global default
2180  */
2181 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2182                               int nodefs)
2183 {
2184         struct ext4_sb_info *sbi = EXT4_SB(sb);
2185         struct ext4_super_block *es = sbi->s_es;
2186         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2187         const struct mount_opts *m;
2188         char sep = nodefs ? '\n' : ',';
2189
2190 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2191 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2192
2193         if (sbi->s_sb_block != 1)
2194                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2195
2196         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2197                 int want_set = m->flags & MOPT_SET;
2198                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2199                     (m->flags & MOPT_CLEAR_ERR))
2200                         continue;
2201                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2202                         continue; /* skip if same as the default */
2203                 if ((want_set &&
2204                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2205                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2206                         continue; /* select Opt_noFoo vs Opt_Foo */
2207                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2208         }
2209
2210         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2211             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2212                 SEQ_OPTS_PRINT("resuid=%u",
2213                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2214         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2215             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2216                 SEQ_OPTS_PRINT("resgid=%u",
2217                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2218         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2219         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2220                 SEQ_OPTS_PUTS("errors=remount-ro");
2221         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2222                 SEQ_OPTS_PUTS("errors=continue");
2223         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2224                 SEQ_OPTS_PUTS("errors=panic");
2225         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2226                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2227         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2228                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2229         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2230                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2231         if (sb->s_flags & SB_I_VERSION)
2232                 SEQ_OPTS_PUTS("i_version");
2233         if (nodefs || sbi->s_stripe)
2234                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2235         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2236                         (sbi->s_mount_opt ^ def_mount_opt)) {
2237                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2238                         SEQ_OPTS_PUTS("data=journal");
2239                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2240                         SEQ_OPTS_PUTS("data=ordered");
2241                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2242                         SEQ_OPTS_PUTS("data=writeback");
2243         }
2244         if (nodefs ||
2245             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2246                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2247                                sbi->s_inode_readahead_blks);
2248
2249         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2250                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2251                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2252         if (nodefs || sbi->s_max_dir_size_kb)
2253                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2254         if (test_opt(sb, DATA_ERR_ABORT))
2255                 SEQ_OPTS_PUTS("data_err=abort");
2256         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2257                 SEQ_OPTS_PUTS("test_dummy_encryption");
2258
2259         ext4_show_quota_options(seq, sb);
2260         return 0;
2261 }
2262
2263 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2264 {
2265         return _ext4_show_options(seq, root->d_sb, 0);
2266 }
2267
2268 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2269 {
2270         struct super_block *sb = seq->private;
2271         int rc;
2272
2273         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2274         rc = _ext4_show_options(seq, sb, 1);
2275         seq_puts(seq, "\n");
2276         return rc;
2277 }
2278
2279 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2280                             int read_only)
2281 {
2282         struct ext4_sb_info *sbi = EXT4_SB(sb);
2283         int err = 0;
2284
2285         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2286                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2287                          "forcing read-only mode");
2288                 err = -EROFS;
2289         }
2290         if (read_only)
2291                 goto done;
2292         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2293                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2294                          "running e2fsck is recommended");
2295         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2296                 ext4_msg(sb, KERN_WARNING,
2297                          "warning: mounting fs with errors, "
2298                          "running e2fsck is recommended");
2299         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2300                  le16_to_cpu(es->s_mnt_count) >=
2301                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2302                 ext4_msg(sb, KERN_WARNING,
2303                          "warning: maximal mount count reached, "
2304                          "running e2fsck is recommended");
2305         else if (le32_to_cpu(es->s_checkinterval) &&
2306                  (ext4_get_tstamp(es, s_lastcheck) +
2307                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2308                 ext4_msg(sb, KERN_WARNING,
2309                          "warning: checktime reached, "
2310                          "running e2fsck is recommended");
2311         if (!sbi->s_journal)
2312                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2313         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2314                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2315         le16_add_cpu(&es->s_mnt_count, 1);
2316         ext4_update_tstamp(es, s_mtime);
2317         if (sbi->s_journal)
2318                 ext4_set_feature_journal_needs_recovery(sb);
2319
2320         err = ext4_commit_super(sb, 1);
2321 done:
2322         if (test_opt(sb, DEBUG))
2323                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2324                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2325                         sb->s_blocksize,
2326                         sbi->s_groups_count,
2327                         EXT4_BLOCKS_PER_GROUP(sb),
2328                         EXT4_INODES_PER_GROUP(sb),
2329                         sbi->s_mount_opt, sbi->s_mount_opt2);
2330
2331         cleancache_init_fs(sb);
2332         return err;
2333 }
2334
2335 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2336 {
2337         struct ext4_sb_info *sbi = EXT4_SB(sb);
2338         struct flex_groups *new_groups;
2339         int size;
2340
2341         if (!sbi->s_log_groups_per_flex)
2342                 return 0;
2343
2344         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2345         if (size <= sbi->s_flex_groups_allocated)
2346                 return 0;
2347
2348         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2349         new_groups = kvzalloc(size, GFP_KERNEL);
2350         if (!new_groups) {
2351                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2352                          size / (int) sizeof(struct flex_groups));
2353                 return -ENOMEM;
2354         }
2355
2356         if (sbi->s_flex_groups) {
2357                 memcpy(new_groups, sbi->s_flex_groups,
2358                        (sbi->s_flex_groups_allocated *
2359                         sizeof(struct flex_groups)));
2360                 kvfree(sbi->s_flex_groups);
2361         }
2362         sbi->s_flex_groups = new_groups;
2363         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2364         return 0;
2365 }
2366
2367 static int ext4_fill_flex_info(struct super_block *sb)
2368 {
2369         struct ext4_sb_info *sbi = EXT4_SB(sb);
2370         struct ext4_group_desc *gdp = NULL;
2371         ext4_group_t flex_group;
2372         int i, err;
2373
2374         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2375         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2376                 sbi->s_log_groups_per_flex = 0;
2377                 return 1;
2378         }
2379
2380         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2381         if (err)
2382                 goto failed;
2383
2384         for (i = 0; i < sbi->s_groups_count; i++) {
2385                 gdp = ext4_get_group_desc(sb, i, NULL);
2386
2387                 flex_group = ext4_flex_group(sbi, i);
2388                 atomic_add(ext4_free_inodes_count(sb, gdp),
2389                            &sbi->s_flex_groups[flex_group].free_inodes);
2390                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2391                              &sbi->s_flex_groups[flex_group].free_clusters);
2392                 atomic_add(ext4_used_dirs_count(sb, gdp),
2393                            &sbi->s_flex_groups[flex_group].used_dirs);
2394         }
2395
2396         return 1;
2397 failed:
2398         return 0;
2399 }
2400
2401 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2402                                    struct ext4_group_desc *gdp)
2403 {
2404         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2405         __u16 crc = 0;
2406         __le32 le_group = cpu_to_le32(block_group);
2407         struct ext4_sb_info *sbi = EXT4_SB(sb);
2408
2409         if (ext4_has_metadata_csum(sbi->s_sb)) {
2410                 /* Use new metadata_csum algorithm */
2411                 __u32 csum32;
2412                 __u16 dummy_csum = 0;
2413
2414                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2415                                      sizeof(le_group));
2416                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2417                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2418                                      sizeof(dummy_csum));
2419                 offset += sizeof(dummy_csum);
2420                 if (offset < sbi->s_desc_size)
2421                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2422                                              sbi->s_desc_size - offset);
2423
2424                 crc = csum32 & 0xFFFF;
2425                 goto out;
2426         }
2427
2428         /* old crc16 code */
2429         if (!ext4_has_feature_gdt_csum(sb))
2430                 return 0;
2431
2432         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2433         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2434         crc = crc16(crc, (__u8 *)gdp, offset);
2435         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2436         /* for checksum of struct ext4_group_desc do the rest...*/
2437         if (ext4_has_feature_64bit(sb) &&
2438             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2439                 crc = crc16(crc, (__u8 *)gdp + offset,
2440                             le16_to_cpu(sbi->s_es->s_desc_size) -
2441                                 offset);
2442
2443 out:
2444         return cpu_to_le16(crc);
2445 }
2446
2447 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2448                                 struct ext4_group_desc *gdp)
2449 {
2450         if (ext4_has_group_desc_csum(sb) &&
2451             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2452                 return 0;
2453
2454         return 1;
2455 }
2456
2457 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2458                               struct ext4_group_desc *gdp)
2459 {
2460         if (!ext4_has_group_desc_csum(sb))
2461                 return;
2462         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2463 }
2464
2465 /* Called at mount-time, super-block is locked */
2466 static int ext4_check_descriptors(struct super_block *sb,
2467                                   ext4_fsblk_t sb_block,
2468                                   ext4_group_t *first_not_zeroed)
2469 {
2470         struct ext4_sb_info *sbi = EXT4_SB(sb);
2471         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2472         ext4_fsblk_t last_block;
2473         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2474         ext4_fsblk_t block_bitmap;
2475         ext4_fsblk_t inode_bitmap;
2476         ext4_fsblk_t inode_table;
2477         int flexbg_flag = 0;
2478         ext4_group_t i, grp = sbi->s_groups_count;
2479
2480         if (ext4_has_feature_flex_bg(sb))
2481                 flexbg_flag = 1;
2482
2483         ext4_debug("Checking group descriptors");
2484
2485         for (i = 0; i < sbi->s_groups_count; i++) {
2486                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2487
2488                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2489                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2490                 else
2491                         last_block = first_block +
2492                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2493
2494                 if ((grp == sbi->s_groups_count) &&
2495                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2496                         grp = i;
2497
2498                 block_bitmap = ext4_block_bitmap(sb, gdp);
2499                 if (block_bitmap == sb_block) {
2500                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2501                                  "Block bitmap for group %u overlaps "
2502                                  "superblock", i);
2503                         if (!sb_rdonly(sb))
2504                                 return 0;
2505                 }
2506                 if (block_bitmap >= sb_block + 1 &&
2507                     block_bitmap <= last_bg_block) {
2508                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2509                                  "Block bitmap for group %u overlaps "
2510                                  "block group descriptors", i);
2511                         if (!sb_rdonly(sb))
2512                                 return 0;
2513                 }
2514                 if (block_bitmap < first_block || block_bitmap > last_block) {
2515                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2516                                "Block bitmap for group %u not in group "
2517                                "(block %llu)!", i, block_bitmap);
2518                         return 0;
2519                 }
2520                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2521                 if (inode_bitmap == sb_block) {
2522                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2523                                  "Inode bitmap for group %u overlaps "
2524                                  "superblock", i);
2525                         if (!sb_rdonly(sb))
2526                                 return 0;
2527                 }
2528                 if (inode_bitmap >= sb_block + 1 &&
2529                     inode_bitmap <= last_bg_block) {
2530                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2531                                  "Inode bitmap for group %u overlaps "
2532                                  "block group descriptors", i);
2533                         if (!sb_rdonly(sb))
2534                                 return 0;
2535                 }
2536                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2537                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2538                                "Inode bitmap for group %u not in group "
2539                                "(block %llu)!", i, inode_bitmap);
2540                         return 0;
2541                 }
2542                 inode_table = ext4_inode_table(sb, gdp);
2543                 if (inode_table == sb_block) {
2544                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2545                                  "Inode table for group %u overlaps "
2546                                  "superblock", i);
2547                         if (!sb_rdonly(sb))
2548                                 return 0;
2549                 }
2550                 if (inode_table >= sb_block + 1 &&
2551                     inode_table <= last_bg_block) {
2552                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2553                                  "Inode table for group %u overlaps "
2554                                  "block group descriptors", i);
2555                         if (!sb_rdonly(sb))
2556                                 return 0;
2557                 }
2558                 if (inode_table < first_block ||
2559                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2560                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2561                                "Inode table for group %u not in group "
2562                                "(block %llu)!", i, inode_table);
2563                         return 0;
2564                 }
2565                 ext4_lock_group(sb, i);
2566                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2567                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2568                                  "Checksum for group %u failed (%u!=%u)",
2569                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2570                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2571                         if (!sb_rdonly(sb)) {
2572                                 ext4_unlock_group(sb, i);
2573                                 return 0;
2574                         }
2575                 }
2576                 ext4_unlock_group(sb, i);
2577                 if (!flexbg_flag)
2578                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2579         }
2580         if (NULL != first_not_zeroed)
2581                 *first_not_zeroed = grp;
2582         return 1;
2583 }
2584
2585 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2586  * the superblock) which were deleted from all directories, but held open by
2587  * a process at the time of a crash.  We walk the list and try to delete these
2588  * inodes at recovery time (only with a read-write filesystem).
2589  *
2590  * In order to keep the orphan inode chain consistent during traversal (in
2591  * case of crash during recovery), we link each inode into the superblock
2592  * orphan list_head and handle it the same way as an inode deletion during
2593  * normal operation (which journals the operations for us).
2594  *
2595  * We only do an iget() and an iput() on each inode, which is very safe if we
2596  * accidentally point at an in-use or already deleted inode.  The worst that
2597  * can happen in this case is that we get a "bit already cleared" message from
2598  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2599  * e2fsck was run on this filesystem, and it must have already done the orphan
2600  * inode cleanup for us, so we can safely abort without any further action.
2601  */
2602 static void ext4_orphan_cleanup(struct super_block *sb,
2603                                 struct ext4_super_block *es)
2604 {
2605         unsigned int s_flags = sb->s_flags;
2606         int ret, nr_orphans = 0, nr_truncates = 0;
2607 #ifdef CONFIG_QUOTA
2608         int quota_update = 0;
2609         int i;
2610 #endif
2611         if (!es->s_last_orphan) {
2612                 jbd_debug(4, "no orphan inodes to clean up\n");
2613                 return;
2614         }
2615
2616         if (bdev_read_only(sb->s_bdev)) {
2617                 ext4_msg(sb, KERN_ERR, "write access "
2618                         "unavailable, skipping orphan cleanup");
2619                 return;
2620         }
2621
2622         /* Check if feature set would not allow a r/w mount */
2623         if (!ext4_feature_set_ok(sb, 0)) {
2624                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2625                          "unknown ROCOMPAT features");
2626                 return;
2627         }
2628
2629         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2630                 /* don't clear list on RO mount w/ errors */
2631                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2632                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2633                                   "clearing orphan list.\n");
2634                         es->s_last_orphan = 0;
2635                 }
2636                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2637                 return;
2638         }
2639
2640         if (s_flags & SB_RDONLY) {
2641                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2642                 sb->s_flags &= ~SB_RDONLY;
2643         }
2644 #ifdef CONFIG_QUOTA
2645         /* Needed for iput() to work correctly and not trash data */
2646         sb->s_flags |= SB_ACTIVE;
2647
2648         /*
2649          * Turn on quotas which were not enabled for read-only mounts if
2650          * filesystem has quota feature, so that they are updated correctly.
2651          */
2652         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2653                 int ret = ext4_enable_quotas(sb);
2654
2655                 if (!ret)
2656                         quota_update = 1;
2657                 else
2658                         ext4_msg(sb, KERN_ERR,
2659                                 "Cannot turn on quotas: error %d", ret);
2660         }
2661
2662         /* Turn on journaled quotas used for old sytle */
2663         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2664                 if (EXT4_SB(sb)->s_qf_names[i]) {
2665                         int ret = ext4_quota_on_mount(sb, i);
2666
2667                         if (!ret)
2668                                 quota_update = 1;
2669                         else
2670                                 ext4_msg(sb, KERN_ERR,
2671                                         "Cannot turn on journaled "
2672                                         "quota: type %d: error %d", i, ret);
2673                 }
2674         }
2675 #endif
2676
2677         while (es->s_last_orphan) {
2678                 struct inode *inode;
2679
2680                 /*
2681                  * We may have encountered an error during cleanup; if
2682                  * so, skip the rest.
2683                  */
2684                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2685                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2686                         es->s_last_orphan = 0;
2687                         break;
2688                 }
2689
2690                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2691                 if (IS_ERR(inode)) {
2692                         es->s_last_orphan = 0;
2693                         break;
2694                 }
2695
2696                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2697                 dquot_initialize(inode);
2698                 if (inode->i_nlink) {
2699                         if (test_opt(sb, DEBUG))
2700                                 ext4_msg(sb, KERN_DEBUG,
2701                                         "%s: truncating inode %lu to %lld bytes",
2702                                         __func__, inode->i_ino, inode->i_size);
2703                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2704                                   inode->i_ino, inode->i_size);
2705                         inode_lock(inode);
2706                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2707                         ret = ext4_truncate(inode);
2708                         if (ret)
2709                                 ext4_std_error(inode->i_sb, ret);
2710                         inode_unlock(inode);
2711                         nr_truncates++;
2712                 } else {
2713                         if (test_opt(sb, DEBUG))
2714                                 ext4_msg(sb, KERN_DEBUG,
2715                                         "%s: deleting unreferenced inode %lu",
2716                                         __func__, inode->i_ino);
2717                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2718                                   inode->i_ino);
2719                         nr_orphans++;
2720                 }
2721                 iput(inode);  /* The delete magic happens here! */
2722         }
2723
2724 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2725
2726         if (nr_orphans)
2727                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2728                        PLURAL(nr_orphans));
2729         if (nr_truncates)
2730                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2731                        PLURAL(nr_truncates));
2732 #ifdef CONFIG_QUOTA
2733         /* Turn off quotas if they were enabled for orphan cleanup */
2734         if (quota_update) {
2735                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2736                         if (sb_dqopt(sb)->files[i])
2737                                 dquot_quota_off(sb, i);
2738                 }
2739         }
2740 #endif
2741         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2742 }
2743
2744 /*
2745  * Maximal extent format file size.
2746  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2747  * extent format containers, within a sector_t, and within i_blocks
2748  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2749  * so that won't be a limiting factor.
2750  *
2751  * However there is other limiting factor. We do store extents in the form
2752  * of starting block and length, hence the resulting length of the extent
2753  * covering maximum file size must fit into on-disk format containers as
2754  * well. Given that length is always by 1 unit bigger than max unit (because
2755  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2756  *
2757  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2758  */
2759 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2760 {
2761         loff_t res;
2762         loff_t upper_limit = MAX_LFS_FILESIZE;
2763
2764         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
2765
2766         if (!has_huge_files) {
2767                 upper_limit = (1LL << 32) - 1;
2768
2769                 /* total blocks in file system block size */
2770                 upper_limit >>= (blkbits - 9);
2771                 upper_limit <<= blkbits;
2772         }
2773
2774         /*
2775          * 32-bit extent-start container, ee_block. We lower the maxbytes
2776          * by one fs block, so ee_len can cover the extent of maximum file
2777          * size
2778          */
2779         res = (1LL << 32) - 1;
2780         res <<= blkbits;
2781
2782         /* Sanity check against vm- & vfs- imposed limits */
2783         if (res > upper_limit)
2784                 res = upper_limit;
2785
2786         return res;
2787 }
2788
2789 /*
2790  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2791  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2792  * We need to be 1 filesystem block less than the 2^48 sector limit.
2793  */
2794 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2795 {
2796         loff_t res = EXT4_NDIR_BLOCKS;
2797         int meta_blocks;
2798         loff_t upper_limit;
2799         /* This is calculated to be the largest file size for a dense, block
2800          * mapped file such that the file's total number of 512-byte sectors,
2801          * including data and all indirect blocks, does not exceed (2^48 - 1).
2802          *
2803          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2804          * number of 512-byte sectors of the file.
2805          */
2806
2807         if (!has_huge_files) {
2808                 /*
2809                  * !has_huge_files or implies that the inode i_block field
2810                  * represents total file blocks in 2^32 512-byte sectors ==
2811                  * size of vfs inode i_blocks * 8
2812                  */
2813                 upper_limit = (1LL << 32) - 1;
2814
2815                 /* total blocks in file system block size */
2816                 upper_limit >>= (bits - 9);
2817
2818         } else {
2819                 /*
2820                  * We use 48 bit ext4_inode i_blocks
2821                  * With EXT4_HUGE_FILE_FL set the i_blocks
2822                  * represent total number of blocks in
2823                  * file system block size
2824                  */
2825                 upper_limit = (1LL << 48) - 1;
2826
2827         }
2828
2829         /* indirect blocks */
2830         meta_blocks = 1;
2831         /* double indirect blocks */
2832         meta_blocks += 1 + (1LL << (bits-2));
2833         /* tripple indirect blocks */
2834         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2835
2836         upper_limit -= meta_blocks;
2837         upper_limit <<= bits;
2838
2839         res += 1LL << (bits-2);
2840         res += 1LL << (2*(bits-2));
2841         res += 1LL << (3*(bits-2));
2842         res <<= bits;
2843         if (res > upper_limit)
2844                 res = upper_limit;
2845
2846         if (res > MAX_LFS_FILESIZE)
2847                 res = MAX_LFS_FILESIZE;
2848
2849         return res;
2850 }
2851
2852 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2853                                    ext4_fsblk_t logical_sb_block, int nr)
2854 {
2855         struct ext4_sb_info *sbi = EXT4_SB(sb);
2856         ext4_group_t bg, first_meta_bg;
2857         int has_super = 0;
2858
2859         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2860
2861         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2862                 return logical_sb_block + nr + 1;
2863         bg = sbi->s_desc_per_block * nr;
2864         if (ext4_bg_has_super(sb, bg))
2865                 has_super = 1;
2866
2867         /*
2868          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2869          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2870          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2871          * compensate.
2872          */
2873         if (sb->s_blocksize == 1024 && nr == 0 &&
2874             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2875                 has_super++;
2876
2877         return (has_super + ext4_group_first_block_no(sb, bg));
2878 }
2879
2880 /**
2881  * ext4_get_stripe_size: Get the stripe size.
2882  * @sbi: In memory super block info
2883  *
2884  * If we have specified it via mount option, then
2885  * use the mount option value. If the value specified at mount time is
2886  * greater than the blocks per group use the super block value.
2887  * If the super block value is greater than blocks per group return 0.
2888  * Allocator needs it be less than blocks per group.
2889  *
2890  */
2891 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2892 {
2893         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2894         unsigned long stripe_width =
2895                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2896         int ret;
2897
2898         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2899                 ret = sbi->s_stripe;
2900         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2901                 ret = stripe_width;
2902         else if (stride && stride <= sbi->s_blocks_per_group)
2903                 ret = stride;
2904         else
2905                 ret = 0;
2906
2907         /*
2908          * If the stripe width is 1, this makes no sense and
2909          * we set it to 0 to turn off stripe handling code.
2910          */
2911         if (ret <= 1)
2912                 ret = 0;
2913
2914         return ret;
2915 }
2916
2917 /*
2918  * Check whether this filesystem can be mounted based on
2919  * the features present and the RDONLY/RDWR mount requested.
2920  * Returns 1 if this filesystem can be mounted as requested,
2921  * 0 if it cannot be.
2922  */
2923 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2924 {
2925         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2926                 ext4_msg(sb, KERN_ERR,
2927                         "Couldn't mount because of "
2928                         "unsupported optional features (%x)",
2929                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2930                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2931                 return 0;
2932         }
2933
2934 #ifndef CONFIG_UNICODE
2935         if (ext4_has_feature_casefold(sb)) {
2936                 ext4_msg(sb, KERN_ERR,
2937                          "Filesystem with casefold feature cannot be "
2938                          "mounted without CONFIG_UNICODE");
2939                 return 0;
2940         }
2941 #endif
2942
2943         if (readonly)
2944                 return 1;
2945
2946         if (ext4_has_feature_readonly(sb)) {
2947                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2948                 sb->s_flags |= SB_RDONLY;
2949                 return 1;
2950         }
2951
2952         /* Check that feature set is OK for a read-write mount */
2953         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2954                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2955                          "unsupported optional features (%x)",
2956                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2957                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2958                 return 0;
2959         }
2960         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2961                 ext4_msg(sb, KERN_ERR,
2962                          "Can't support bigalloc feature without "
2963                          "extents feature\n");
2964                 return 0;
2965         }
2966
2967 #ifndef CONFIG_QUOTA
2968         if (ext4_has_feature_quota(sb) && !readonly) {
2969                 ext4_msg(sb, KERN_ERR,
2970                          "Filesystem with quota feature cannot be mounted RDWR "
2971                          "without CONFIG_QUOTA");
2972                 return 0;
2973         }
2974         if (ext4_has_feature_project(sb) && !readonly) {
2975                 ext4_msg(sb, KERN_ERR,
2976                          "Filesystem with project quota feature cannot be mounted RDWR "
2977                          "without CONFIG_QUOTA");
2978                 return 0;
2979         }
2980 #endif  /* CONFIG_QUOTA */
2981         return 1;
2982 }
2983
2984 /*
2985  * This function is called once a day if we have errors logged
2986  * on the file system
2987  */
2988 static void print_daily_error_info(struct timer_list *t)
2989 {
2990         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2991         struct super_block *sb = sbi->s_sb;
2992         struct ext4_super_block *es = sbi->s_es;
2993
2994         if (es->s_error_count)
2995                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2996                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2997                          le32_to_cpu(es->s_error_count));
2998         if (es->s_first_error_time) {
2999                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3000                        sb->s_id,
3001                        ext4_get_tstamp(es, s_first_error_time),
3002                        (int) sizeof(es->s_first_error_func),
3003                        es->s_first_error_func,
3004                        le32_to_cpu(es->s_first_error_line));
3005                 if (es->s_first_error_ino)
3006                         printk(KERN_CONT ": inode %u",
3007                                le32_to_cpu(es->s_first_error_ino));
3008                 if (es->s_first_error_block)
3009                         printk(KERN_CONT ": block %llu", (unsigned long long)
3010                                le64_to_cpu(es->s_first_error_block));
3011                 printk(KERN_CONT "\n");
3012         }
3013         if (es->s_last_error_time) {
3014                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3015                        sb->s_id,
3016                        ext4_get_tstamp(es, s_last_error_time),
3017                        (int) sizeof(es->s_last_error_func),
3018                        es->s_last_error_func,
3019                        le32_to_cpu(es->s_last_error_line));
3020                 if (es->s_last_error_ino)
3021                         printk(KERN_CONT ": inode %u",
3022                                le32_to_cpu(es->s_last_error_ino));
3023                 if (es->s_last_error_block)
3024                         printk(KERN_CONT ": block %llu", (unsigned long long)
3025                                le64_to_cpu(es->s_last_error_block));
3026                 printk(KERN_CONT "\n");
3027         }
3028         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3029 }
3030
3031 /* Find next suitable group and run ext4_init_inode_table */
3032 static int ext4_run_li_request(struct ext4_li_request *elr)
3033 {
3034         struct ext4_group_desc *gdp = NULL;
3035         ext4_group_t group, ngroups;
3036         struct super_block *sb;
3037         unsigned long timeout = 0;
3038         int ret = 0;
3039
3040         sb = elr->lr_super;
3041         ngroups = EXT4_SB(sb)->s_groups_count;
3042
3043         for (group = elr->lr_next_group; group < ngroups; group++) {
3044                 gdp = ext4_get_group_desc(sb, group, NULL);
3045                 if (!gdp) {
3046                         ret = 1;
3047                         break;
3048                 }
3049
3050                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3051                         break;
3052         }
3053
3054         if (group >= ngroups)
3055                 ret = 1;
3056
3057         if (!ret) {
3058                 timeout = jiffies;
3059                 ret = ext4_init_inode_table(sb, group,
3060                                             elr->lr_timeout ? 0 : 1);
3061                 if (elr->lr_timeout == 0) {
3062                         timeout = (jiffies - timeout) *
3063                                   elr->lr_sbi->s_li_wait_mult;
3064                         elr->lr_timeout = timeout;
3065                 }
3066                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3067                 elr->lr_next_group = group + 1;
3068         }
3069         return ret;
3070 }
3071
3072 /*
3073  * Remove lr_request from the list_request and free the
3074  * request structure. Should be called with li_list_mtx held
3075  */
3076 static void ext4_remove_li_request(struct ext4_li_request *elr)
3077 {
3078         struct ext4_sb_info *sbi;
3079
3080         if (!elr)
3081                 return;
3082
3083         sbi = elr->lr_sbi;
3084
3085         list_del(&elr->lr_request);
3086         sbi->s_li_request = NULL;
3087         kfree(elr);
3088 }
3089
3090 static void ext4_unregister_li_request(struct super_block *sb)
3091 {
3092         mutex_lock(&ext4_li_mtx);
3093         if (!ext4_li_info) {
3094                 mutex_unlock(&ext4_li_mtx);
3095                 return;
3096         }
3097
3098         mutex_lock(&ext4_li_info->li_list_mtx);
3099         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3100         mutex_unlock(&ext4_li_info->li_list_mtx);
3101         mutex_unlock(&ext4_li_mtx);
3102 }
3103
3104 static struct task_struct *ext4_lazyinit_task;
3105
3106 /*
3107  * This is the function where ext4lazyinit thread lives. It walks
3108  * through the request list searching for next scheduled filesystem.
3109  * When such a fs is found, run the lazy initialization request
3110  * (ext4_rn_li_request) and keep track of the time spend in this
3111  * function. Based on that time we compute next schedule time of
3112  * the request. When walking through the list is complete, compute
3113  * next waking time and put itself into sleep.
3114  */
3115 static int ext4_lazyinit_thread(void *arg)
3116 {
3117         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3118         struct list_head *pos, *n;
3119         struct ext4_li_request *elr;
3120         unsigned long next_wakeup, cur;
3121
3122         BUG_ON(NULL == eli);
3123
3124 cont_thread:
3125         while (true) {
3126                 next_wakeup = MAX_JIFFY_OFFSET;
3127
3128                 mutex_lock(&eli->li_list_mtx);
3129                 if (list_empty(&eli->li_request_list)) {
3130                         mutex_unlock(&eli->li_list_mtx);
3131                         goto exit_thread;
3132                 }
3133                 list_for_each_safe(pos, n, &eli->li_request_list) {
3134                         int err = 0;
3135                         int progress = 0;
3136                         elr = list_entry(pos, struct ext4_li_request,
3137                                          lr_request);
3138
3139                         if (time_before(jiffies, elr->lr_next_sched)) {
3140                                 if (time_before(elr->lr_next_sched, next_wakeup))
3141                                         next_wakeup = elr->lr_next_sched;
3142                                 continue;
3143                         }
3144                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3145                                 if (sb_start_write_trylock(elr->lr_super)) {
3146                                         progress = 1;
3147                                         /*
3148                                          * We hold sb->s_umount, sb can not
3149                                          * be removed from the list, it is
3150                                          * now safe to drop li_list_mtx
3151                                          */
3152                                         mutex_unlock(&eli->li_list_mtx);
3153                                         err = ext4_run_li_request(elr);
3154                                         sb_end_write(elr->lr_super);
3155                                         mutex_lock(&eli->li_list_mtx);
3156                                         n = pos->next;
3157                                 }
3158                                 up_read((&elr->lr_super->s_umount));
3159                         }
3160                         /* error, remove the lazy_init job */
3161                         if (err) {
3162                                 ext4_remove_li_request(elr);
3163                                 continue;
3164                         }
3165                         if (!progress) {
3166                                 elr->lr_next_sched = jiffies +
3167                                         (prandom_u32()
3168                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3169                         }
3170                         if (time_before(elr->lr_next_sched, next_wakeup))
3171                                 next_wakeup = elr->lr_next_sched;
3172                 }
3173                 mutex_unlock(&eli->li_list_mtx);
3174
3175                 try_to_freeze();
3176
3177                 cur = jiffies;
3178                 if ((time_after_eq(cur, next_wakeup)) ||
3179                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3180                         cond_resched();
3181                         continue;
3182                 }
3183
3184                 schedule_timeout_interruptible(next_wakeup - cur);
3185
3186                 if (kthread_should_stop()) {
3187                         ext4_clear_request_list();
3188                         goto exit_thread;
3189                 }
3190         }
3191
3192 exit_thread:
3193         /*
3194          * It looks like the request list is empty, but we need
3195          * to check it under the li_list_mtx lock, to prevent any
3196          * additions into it, and of course we should lock ext4_li_mtx
3197          * to atomically free the list and ext4_li_info, because at
3198          * this point another ext4 filesystem could be registering
3199          * new one.
3200          */
3201         mutex_lock(&ext4_li_mtx);
3202         mutex_lock(&eli->li_list_mtx);
3203         if (!list_empty(&eli->li_request_list)) {
3204                 mutex_unlock(&eli->li_list_mtx);
3205                 mutex_unlock(&ext4_li_mtx);
3206                 goto cont_thread;
3207         }
3208         mutex_unlock(&eli->li_list_mtx);
3209         kfree(ext4_li_info);
3210         ext4_li_info = NULL;
3211         mutex_unlock(&ext4_li_mtx);
3212
3213         return 0;
3214 }
3215
3216 static void ext4_clear_request_list(void)
3217 {
3218         struct list_head *pos, *n;
3219         struct ext4_li_request *elr;
3220
3221         mutex_lock(&ext4_li_info->li_list_mtx);
3222         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3223                 elr = list_entry(pos, struct ext4_li_request,
3224                                  lr_request);
3225                 ext4_remove_li_request(elr);
3226         }
3227         mutex_unlock(&ext4_li_info->li_list_mtx);
3228 }
3229
3230 static int ext4_run_lazyinit_thread(void)
3231 {
3232         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3233                                          ext4_li_info, "ext4lazyinit");
3234         if (IS_ERR(ext4_lazyinit_task)) {
3235                 int err = PTR_ERR(ext4_lazyinit_task);
3236                 ext4_clear_request_list();
3237                 kfree(ext4_li_info);
3238                 ext4_li_info = NULL;
3239                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3240                                  "initialization thread\n",
3241                                  err);
3242                 return err;
3243         }
3244         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3245         return 0;
3246 }
3247
3248 /*
3249  * Check whether it make sense to run itable init. thread or not.
3250  * If there is at least one uninitialized inode table, return
3251  * corresponding group number, else the loop goes through all
3252  * groups and return total number of groups.
3253  */
3254 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3255 {
3256         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3257         struct ext4_group_desc *gdp = NULL;
3258
3259         if (!ext4_has_group_desc_csum(sb))
3260                 return ngroups;
3261
3262         for (group = 0; group < ngroups; group++) {
3263                 gdp = ext4_get_group_desc(sb, group, NULL);
3264                 if (!gdp)
3265                         continue;
3266
3267                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3268                         break;
3269         }
3270
3271         return group;
3272 }
3273
3274 static int ext4_li_info_new(void)
3275 {
3276         struct ext4_lazy_init *eli = NULL;
3277
3278         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3279         if (!eli)
3280                 return -ENOMEM;
3281
3282         INIT_LIST_HEAD(&eli->li_request_list);
3283         mutex_init(&eli->li_list_mtx);
3284
3285         eli->li_state |= EXT4_LAZYINIT_QUIT;
3286
3287         ext4_li_info = eli;
3288
3289         return 0;
3290 }
3291
3292 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3293                                             ext4_group_t start)
3294 {
3295         struct ext4_sb_info *sbi = EXT4_SB(sb);
3296         struct ext4_li_request *elr;
3297
3298         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3299         if (!elr)
3300                 return NULL;
3301
3302         elr->lr_super = sb;
3303         elr->lr_sbi = sbi;
3304         elr->lr_next_group = start;
3305
3306         /*
3307          * Randomize first schedule time of the request to
3308          * spread the inode table initialization requests
3309          * better.
3310          */
3311         elr->lr_next_sched = jiffies + (prandom_u32() %
3312                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3313         return elr;
3314 }
3315
3316 int ext4_register_li_request(struct super_block *sb,
3317                              ext4_group_t first_not_zeroed)
3318 {
3319         struct ext4_sb_info *sbi = EXT4_SB(sb);
3320         struct ext4_li_request *elr = NULL;
3321         ext4_group_t ngroups = sbi->s_groups_count;
3322         int ret = 0;
3323
3324         mutex_lock(&ext4_li_mtx);
3325         if (sbi->s_li_request != NULL) {
3326                 /*
3327                  * Reset timeout so it can be computed again, because
3328                  * s_li_wait_mult might have changed.
3329                  */
3330                 sbi->s_li_request->lr_timeout = 0;
3331                 goto out;
3332         }
3333
3334         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3335             !test_opt(sb, INIT_INODE_TABLE))
3336                 goto out;
3337
3338         elr = ext4_li_request_new(sb, first_not_zeroed);
3339         if (!elr) {
3340                 ret = -ENOMEM;
3341                 goto out;
3342         }
3343
3344         if (NULL == ext4_li_info) {
3345                 ret = ext4_li_info_new();
3346                 if (ret)
3347                         goto out;
3348         }
3349
3350         mutex_lock(&ext4_li_info->li_list_mtx);
3351         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3352         mutex_unlock(&ext4_li_info->li_list_mtx);
3353
3354         sbi->s_li_request = elr;
3355         /*
3356          * set elr to NULL here since it has been inserted to
3357          * the request_list and the removal and free of it is
3358          * handled by ext4_clear_request_list from now on.
3359          */
3360         elr = NULL;
3361
3362         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3363                 ret = ext4_run_lazyinit_thread();
3364                 if (ret)
3365                         goto out;
3366         }
3367 out:
3368         mutex_unlock(&ext4_li_mtx);
3369         if (ret)
3370                 kfree(elr);
3371         return ret;
3372 }
3373
3374 /*
3375  * We do not need to lock anything since this is called on
3376  * module unload.
3377  */
3378 static void ext4_destroy_lazyinit_thread(void)
3379 {
3380         /*
3381          * If thread exited earlier
3382          * there's nothing to be done.
3383          */
3384         if (!ext4_li_info || !ext4_lazyinit_task)
3385                 return;
3386
3387         kthread_stop(ext4_lazyinit_task);
3388 }
3389
3390 static int set_journal_csum_feature_set(struct super_block *sb)
3391 {
3392         int ret = 1;
3393         int compat, incompat;
3394         struct ext4_sb_info *sbi = EXT4_SB(sb);
3395
3396         if (ext4_has_metadata_csum(sb)) {
3397                 /* journal checksum v3 */
3398                 compat = 0;
3399                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3400         } else {
3401                 /* journal checksum v1 */
3402                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3403                 incompat = 0;
3404         }
3405
3406         jbd2_journal_clear_features(sbi->s_journal,
3407                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3408                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3409                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3410         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3411                 ret = jbd2_journal_set_features(sbi->s_journal,
3412                                 compat, 0,
3413                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3414                                 incompat);
3415         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3416                 ret = jbd2_journal_set_features(sbi->s_journal,
3417                                 compat, 0,
3418                                 incompat);
3419                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3420                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3421         } else {
3422                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3423                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3424         }
3425
3426         return ret;
3427 }
3428
3429 /*
3430  * Note: calculating the overhead so we can be compatible with
3431  * historical BSD practice is quite difficult in the face of
3432  * clusters/bigalloc.  This is because multiple metadata blocks from
3433  * different block group can end up in the same allocation cluster.
3434  * Calculating the exact overhead in the face of clustered allocation
3435  * requires either O(all block bitmaps) in memory or O(number of block
3436  * groups**2) in time.  We will still calculate the superblock for
3437  * older file systems --- and if we come across with a bigalloc file
3438  * system with zero in s_overhead_clusters the estimate will be close to
3439  * correct especially for very large cluster sizes --- but for newer
3440  * file systems, it's better to calculate this figure once at mkfs
3441  * time, and store it in the superblock.  If the superblock value is
3442  * present (even for non-bigalloc file systems), we will use it.
3443  */
3444 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3445                           char *buf)
3446 {
3447         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3448         struct ext4_group_desc  *gdp;
3449         ext4_fsblk_t            first_block, last_block, b;
3450         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3451         int                     s, j, count = 0;
3452
3453         if (!ext4_has_feature_bigalloc(sb))
3454                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3455                         sbi->s_itb_per_group + 2);
3456
3457         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3458                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3459         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3460         for (i = 0; i < ngroups; i++) {
3461                 gdp = ext4_get_group_desc(sb, i, NULL);
3462                 b = ext4_block_bitmap(sb, gdp);
3463                 if (b >= first_block && b <= last_block) {
3464                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3465                         count++;
3466                 }
3467                 b = ext4_inode_bitmap(sb, gdp);
3468                 if (b >= first_block && b <= last_block) {
3469                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3470                         count++;
3471                 }
3472                 b = ext4_inode_table(sb, gdp);
3473                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3474                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3475                                 int c = EXT4_B2C(sbi, b - first_block);
3476                                 ext4_set_bit(c, buf);
3477                                 count++;
3478                         }
3479                 if (i != grp)
3480                         continue;
3481                 s = 0;
3482                 if (ext4_bg_has_super(sb, grp)) {
3483                         ext4_set_bit(s++, buf);
3484                         count++;
3485                 }
3486                 j = ext4_bg_num_gdb(sb, grp);
3487                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3488                         ext4_error(sb, "Invalid number of block group "
3489                                    "descriptor blocks: %d", j);
3490                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3491                 }
3492                 count += j;
3493                 for (; j > 0; j--)
3494                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3495         }
3496         if (!count)
3497                 return 0;
3498         return EXT4_CLUSTERS_PER_GROUP(sb) -
3499                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3500 }
3501
3502 /*
3503  * Compute the overhead and stash it in sbi->s_overhead
3504  */
3505 int ext4_calculate_overhead(struct super_block *sb)
3506 {
3507         struct ext4_sb_info *sbi = EXT4_SB(sb);
3508         struct ext4_super_block *es = sbi->s_es;
3509         struct inode *j_inode;
3510         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3511         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3512         ext4_fsblk_t overhead = 0;
3513         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3514
3515         if (!buf)
3516                 return -ENOMEM;
3517
3518         /*
3519          * Compute the overhead (FS structures).  This is constant
3520          * for a given filesystem unless the number of block groups
3521          * changes so we cache the previous value until it does.
3522          */
3523
3524         /*
3525          * All of the blocks before first_data_block are overhead
3526          */
3527         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3528
3529         /*
3530          * Add the overhead found in each block group
3531          */
3532         for (i = 0; i < ngroups; i++) {
3533                 int blks;
3534
3535                 blks = count_overhead(sb, i, buf);
3536                 overhead += blks;
3537                 if (blks)
3538                         memset(buf, 0, PAGE_SIZE);
3539                 cond_resched();
3540         }
3541
3542         /*
3543          * Add the internal journal blocks whether the journal has been
3544          * loaded or not
3545          */
3546         if (sbi->s_journal && !sbi->journal_bdev)
3547                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3548         else if (ext4_has_feature_journal(sb) && !sbi->s_journal) {
3549                 j_inode = ext4_get_journal_inode(sb, j_inum);
3550                 if (j_inode) {
3551                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3552                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3553                         iput(j_inode);
3554                 } else {
3555                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3556                 }
3557         }
3558         sbi->s_overhead = overhead;
3559         smp_wmb();
3560         free_page((unsigned long) buf);
3561         return 0;
3562 }
3563
3564 static void ext4_set_resv_clusters(struct super_block *sb)
3565 {
3566         ext4_fsblk_t resv_clusters;
3567         struct ext4_sb_info *sbi = EXT4_SB(sb);
3568
3569         /*
3570          * There's no need to reserve anything when we aren't using extents.
3571          * The space estimates are exact, there are no unwritten extents,
3572          * hole punching doesn't need new metadata... This is needed especially
3573          * to keep ext2/3 backward compatibility.
3574          */
3575         if (!ext4_has_feature_extents(sb))
3576                 return;
3577         /*
3578          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3579          * This should cover the situations where we can not afford to run
3580          * out of space like for example punch hole, or converting
3581          * unwritten extents in delalloc path. In most cases such
3582          * allocation would require 1, or 2 blocks, higher numbers are
3583          * very rare.
3584          */
3585         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3586                          sbi->s_cluster_bits);
3587
3588         do_div(resv_clusters, 50);
3589         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3590
3591         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3592 }
3593
3594 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3595 {
3596         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
3597         char *orig_data = kstrdup(data, GFP_KERNEL);
3598         struct buffer_head *bh;
3599         struct ext4_super_block *es = NULL;
3600         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3601         ext4_fsblk_t block;
3602         ext4_fsblk_t sb_block = get_sb_block(&data);
3603         ext4_fsblk_t logical_sb_block;
3604         unsigned long offset = 0;
3605         unsigned long journal_devnum = 0;
3606         unsigned long def_mount_opts;
3607         struct inode *root;
3608         const char *descr;
3609         int ret = -ENOMEM;
3610         int blocksize, clustersize;
3611         unsigned int db_count;
3612         unsigned int i;
3613         int needs_recovery, has_huge_files, has_bigalloc;
3614         __u64 blocks_count;
3615         int err = 0;
3616         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3617         ext4_group_t first_not_zeroed;
3618
3619         if ((data && !orig_data) || !sbi)
3620                 goto out_free_base;
3621
3622         sbi->s_daxdev = dax_dev;
3623         sbi->s_blockgroup_lock =
3624                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3625         if (!sbi->s_blockgroup_lock)
3626                 goto out_free_base;
3627
3628         sb->s_fs_info = sbi;
3629         sbi->s_sb = sb;
3630         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3631         sbi->s_sb_block = sb_block;
3632         if (sb->s_bdev->bd_part)
3633                 sbi->s_sectors_written_start =
3634                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
3635
3636         /* Cleanup superblock name */
3637         strreplace(sb->s_id, '/', '!');
3638
3639         /* -EINVAL is default */
3640         ret = -EINVAL;
3641         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3642         if (!blocksize) {
3643                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3644                 goto out_fail;
3645         }
3646
3647         /*
3648          * The ext4 superblock will not be buffer aligned for other than 1kB
3649          * block sizes.  We need to calculate the offset from buffer start.
3650          */
3651         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3652                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3653                 offset = do_div(logical_sb_block, blocksize);
3654         } else {
3655                 logical_sb_block = sb_block;
3656         }
3657
3658         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3659                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3660                 goto out_fail;
3661         }
3662         /*
3663          * Note: s_es must be initialized as soon as possible because
3664          *       some ext4 macro-instructions depend on its value
3665          */
3666         es = (struct ext4_super_block *) (bh->b_data + offset);
3667         sbi->s_es = es;
3668         sb->s_magic = le16_to_cpu(es->s_magic);
3669         if (sb->s_magic != EXT4_SUPER_MAGIC)
3670                 goto cantfind_ext4;
3671         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3672
3673         /* Warn if metadata_csum and gdt_csum are both set. */
3674         if (ext4_has_feature_metadata_csum(sb) &&
3675             ext4_has_feature_gdt_csum(sb))
3676                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3677                              "redundant flags; please run fsck.");
3678
3679         /* Check for a known checksum algorithm */
3680         if (!ext4_verify_csum_type(sb, es)) {
3681                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3682                          "unknown checksum algorithm.");
3683                 silent = 1;
3684                 goto cantfind_ext4;
3685         }
3686
3687         /* Load the checksum driver */
3688         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3689         if (IS_ERR(sbi->s_chksum_driver)) {
3690                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3691                 ret = PTR_ERR(sbi->s_chksum_driver);
3692                 sbi->s_chksum_driver = NULL;
3693                 goto failed_mount;
3694         }
3695
3696         /* Check superblock checksum */
3697         if (!ext4_superblock_csum_verify(sb, es)) {
3698                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3699                          "invalid superblock checksum.  Run e2fsck?");
3700                 silent = 1;
3701                 ret = -EFSBADCRC;
3702                 goto cantfind_ext4;
3703         }
3704
3705         /* Precompute checksum seed for all metadata */
3706         if (ext4_has_feature_csum_seed(sb))
3707                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3708         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
3709                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3710                                                sizeof(es->s_uuid));
3711
3712         /* Set defaults before we parse the mount options */
3713         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3714         set_opt(sb, INIT_INODE_TABLE);
3715         if (def_mount_opts & EXT4_DEFM_DEBUG)
3716                 set_opt(sb, DEBUG);
3717         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3718                 set_opt(sb, GRPID);
3719         if (def_mount_opts & EXT4_DEFM_UID16)
3720                 set_opt(sb, NO_UID32);
3721         /* xattr user namespace & acls are now defaulted on */
3722         set_opt(sb, XATTR_USER);
3723 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3724         set_opt(sb, POSIX_ACL);
3725 #endif
3726         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3727         if (ext4_has_metadata_csum(sb))
3728                 set_opt(sb, JOURNAL_CHECKSUM);
3729
3730         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3731                 set_opt(sb, JOURNAL_DATA);
3732         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3733                 set_opt(sb, ORDERED_DATA);
3734         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3735                 set_opt(sb, WRITEBACK_DATA);
3736
3737         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3738                 set_opt(sb, ERRORS_PANIC);
3739         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3740                 set_opt(sb, ERRORS_CONT);
3741         else
3742                 set_opt(sb, ERRORS_RO);
3743         /* block_validity enabled by default; disable with noblock_validity */
3744         set_opt(sb, BLOCK_VALIDITY);
3745         if (def_mount_opts & EXT4_DEFM_DISCARD)
3746                 set_opt(sb, DISCARD);
3747
3748         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3749         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3750         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3751         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3752         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3753
3754         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3755                 set_opt(sb, BARRIER);
3756
3757         /*
3758          * enable delayed allocation by default
3759          * Use -o nodelalloc to turn it off
3760          */
3761         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3762             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3763                 set_opt(sb, DELALLOC);
3764
3765         /*
3766          * set default s_li_wait_mult for lazyinit, for the case there is
3767          * no mount option specified.
3768          */
3769         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3770
3771         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3772                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3773                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3774         } else {
3775                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3776                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3777                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3778                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3779                                  sbi->s_first_ino);
3780                         goto failed_mount;
3781                 }
3782                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3783                     (!is_power_of_2(sbi->s_inode_size)) ||
3784                     (sbi->s_inode_size > blocksize)) {
3785                         ext4_msg(sb, KERN_ERR,
3786                                "unsupported inode size: %d",
3787                                sbi->s_inode_size);
3788                         goto failed_mount;
3789                 }
3790                 /*
3791                  * i_atime_extra is the last extra field available for
3792                  * [acm]times in struct ext4_inode. Checking for that
3793                  * field should suffice to ensure we have extra space
3794                  * for all three.
3795                  */
3796                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
3797                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
3798                         sb->s_time_gran = 1;
3799                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
3800                 } else {
3801                         sb->s_time_gran = NSEC_PER_SEC;
3802                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
3803                 }
3804                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
3805         }
3806         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
3807                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
3808                         EXT4_GOOD_OLD_INODE_SIZE;
3809                 if (ext4_has_feature_extra_isize(sb)) {
3810                         unsigned v, max = (sbi->s_inode_size -
3811                                            EXT4_GOOD_OLD_INODE_SIZE);
3812
3813                         v = le16_to_cpu(es->s_want_extra_isize);
3814                         if (v > max) {
3815                                 ext4_msg(sb, KERN_ERR,
3816                                          "bad s_want_extra_isize: %d", v);
3817                                 goto failed_mount;
3818                         }
3819                         if (sbi->s_want_extra_isize < v)
3820                                 sbi->s_want_extra_isize = v;
3821
3822                         v = le16_to_cpu(es->s_min_extra_isize);
3823                         if (v > max) {
3824                                 ext4_msg(sb, KERN_ERR,
3825                                          "bad s_min_extra_isize: %d", v);
3826                                 goto failed_mount;
3827                         }
3828                         if (sbi->s_want_extra_isize < v)
3829                                 sbi->s_want_extra_isize = v;
3830                 }
3831         }
3832
3833         if (sbi->s_es->s_mount_opts[0]) {
3834                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3835                                               sizeof(sbi->s_es->s_mount_opts),
3836                                               GFP_KERNEL);
3837                 if (!s_mount_opts)
3838                         goto failed_mount;
3839                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3840                                    &journal_ioprio, 0)) {
3841                         ext4_msg(sb, KERN_WARNING,
3842                                  "failed to parse options in superblock: %s",
3843                                  s_mount_opts);
3844                 }
3845                 kfree(s_mount_opts);
3846         }
3847         sbi->s_def_mount_opt = sbi->s_mount_opt;
3848         if (!parse_options((char *) data, sb, &journal_devnum,
3849                            &journal_ioprio, 0))
3850                 goto failed_mount;
3851
3852 #ifdef CONFIG_UNICODE
3853         if (ext4_has_feature_casefold(sb) && !sbi->s_encoding) {
3854                 const struct ext4_sb_encodings *encoding_info;
3855                 struct unicode_map *encoding;
3856                 __u16 encoding_flags;
3857
3858                 if (ext4_has_feature_encrypt(sb)) {
3859                         ext4_msg(sb, KERN_ERR,
3860                                  "Can't mount with encoding and encryption");
3861                         goto failed_mount;
3862                 }
3863
3864                 if (ext4_sb_read_encoding(es, &encoding_info,
3865                                           &encoding_flags)) {
3866                         ext4_msg(sb, KERN_ERR,
3867                                  "Encoding requested by superblock is unknown");
3868                         goto failed_mount;
3869                 }
3870
3871                 encoding = utf8_load(encoding_info->version);
3872                 if (IS_ERR(encoding)) {
3873                         ext4_msg(sb, KERN_ERR,
3874                                  "can't mount with superblock charset: %s-%s "
3875                                  "not supported by the kernel. flags: 0x%x.",
3876                                  encoding_info->name, encoding_info->version,
3877                                  encoding_flags);
3878                         goto failed_mount;
3879                 }
3880                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
3881                          "%s-%s with flags 0x%hx", encoding_info->name,
3882                          encoding_info->version?:"\b", encoding_flags);
3883
3884                 sbi->s_encoding = encoding;
3885                 sbi->s_encoding_flags = encoding_flags;
3886         }
3887 #endif
3888
3889         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3890                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3891                             "with data=journal disables delayed "
3892                             "allocation and O_DIRECT support!\n");
3893                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3894                         ext4_msg(sb, KERN_ERR, "can't mount with "
3895                                  "both data=journal and delalloc");
3896                         goto failed_mount;
3897                 }
3898                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3899                         ext4_msg(sb, KERN_ERR, "can't mount with "
3900                                  "both data=journal and dioread_nolock");
3901                         goto failed_mount;
3902                 }
3903                 if (test_opt(sb, DAX)) {
3904                         ext4_msg(sb, KERN_ERR, "can't mount with "
3905                                  "both data=journal and dax");
3906                         goto failed_mount;
3907                 }
3908                 if (ext4_has_feature_encrypt(sb)) {
3909                         ext4_msg(sb, KERN_WARNING,
3910                                  "encrypted files will use data=ordered "
3911                                  "instead of data journaling mode");
3912                 }
3913                 if (test_opt(sb, DELALLOC))
3914                         clear_opt(sb, DELALLOC);
3915         } else {
3916                 sb->s_iflags |= SB_I_CGROUPWB;
3917         }
3918
3919         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
3920                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
3921
3922         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3923             (ext4_has_compat_features(sb) ||
3924              ext4_has_ro_compat_features(sb) ||
3925              ext4_has_incompat_features(sb)))
3926                 ext4_msg(sb, KERN_WARNING,
3927                        "feature flags set on rev 0 fs, "
3928                        "running e2fsck is recommended");
3929
3930         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3931                 set_opt2(sb, HURD_COMPAT);
3932                 if (ext4_has_feature_64bit(sb)) {
3933                         ext4_msg(sb, KERN_ERR,
3934                                  "The Hurd can't support 64-bit file systems");
3935                         goto failed_mount;
3936                 }
3937
3938                 /*
3939                  * ea_inode feature uses l_i_version field which is not
3940                  * available in HURD_COMPAT mode.
3941                  */
3942                 if (ext4_has_feature_ea_inode(sb)) {
3943                         ext4_msg(sb, KERN_ERR,
3944                                  "ea_inode feature is not supported for Hurd");
3945                         goto failed_mount;
3946                 }
3947         }
3948
3949         if (IS_EXT2_SB(sb)) {
3950                 if (ext2_feature_set_ok(sb))
3951                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3952                                  "using the ext4 subsystem");
3953                 else {
3954                         /*
3955                          * If we're probing be silent, if this looks like
3956                          * it's actually an ext[34] filesystem.
3957                          */
3958                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3959                                 goto failed_mount;
3960                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3961                                  "to feature incompatibilities");
3962                         goto failed_mount;
3963                 }
3964         }
3965
3966         if (IS_EXT3_SB(sb)) {
3967                 if (ext3_feature_set_ok(sb))
3968                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3969                                  "using the ext4 subsystem");
3970                 else {
3971                         /*
3972                          * If we're probing be silent, if this looks like
3973                          * it's actually an ext4 filesystem.
3974                          */
3975                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
3976                                 goto failed_mount;
3977                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3978                                  "to feature incompatibilities");
3979                         goto failed_mount;
3980                 }
3981         }
3982
3983         /*
3984          * Check feature flags regardless of the revision level, since we
3985          * previously didn't change the revision level when setting the flags,
3986          * so there is a chance incompat flags are set on a rev 0 filesystem.
3987          */
3988         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
3989                 goto failed_mount;
3990
3991         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3992         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3993             blocksize > EXT4_MAX_BLOCK_SIZE) {
3994                 ext4_msg(sb, KERN_ERR,
3995                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3996                          blocksize, le32_to_cpu(es->s_log_block_size));
3997                 goto failed_mount;
3998         }
3999         if (le32_to_cpu(es->s_log_block_size) >
4000             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4001                 ext4_msg(sb, KERN_ERR,
4002                          "Invalid log block size: %u",
4003                          le32_to_cpu(es->s_log_block_size));
4004                 goto failed_mount;
4005         }
4006         if (le32_to_cpu(es->s_log_cluster_size) >
4007             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4008                 ext4_msg(sb, KERN_ERR,
4009                          "Invalid log cluster size: %u",
4010                          le32_to_cpu(es->s_log_cluster_size));
4011                 goto failed_mount;
4012         }
4013
4014         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4015                 ext4_msg(sb, KERN_ERR,
4016                          "Number of reserved GDT blocks insanely large: %d",
4017                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4018                 goto failed_mount;
4019         }
4020
4021         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
4022                 if (ext4_has_feature_inline_data(sb)) {
4023                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4024                                         " that may contain inline data");
4025                         goto failed_mount;
4026                 }
4027                 if (!bdev_dax_supported(sb->s_bdev, blocksize)) {
4028                         ext4_msg(sb, KERN_ERR,
4029                                 "DAX unsupported by block device.");
4030                         goto failed_mount;
4031                 }
4032         }
4033
4034         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4035                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4036                          es->s_encryption_level);
4037                 goto failed_mount;
4038         }
4039
4040         if (sb->s_blocksize != blocksize) {
4041                 /* Validate the filesystem blocksize */
4042                 if (!sb_set_blocksize(sb, blocksize)) {
4043                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4044                                         blocksize);
4045                         goto failed_mount;
4046                 }
4047
4048                 brelse(bh);
4049                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4050                 offset = do_div(logical_sb_block, blocksize);
4051                 bh = sb_bread_unmovable(sb, logical_sb_block);
4052                 if (!bh) {
4053                         ext4_msg(sb, KERN_ERR,
4054                                "Can't read superblock on 2nd try");
4055                         goto failed_mount;
4056                 }
4057                 es = (struct ext4_super_block *)(bh->b_data + offset);
4058                 sbi->s_es = es;
4059                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4060                         ext4_msg(sb, KERN_ERR,
4061                                "Magic mismatch, very weird!");
4062                         goto failed_mount;
4063                 }
4064         }
4065
4066         has_huge_files = ext4_has_feature_huge_file(sb);
4067         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4068                                                       has_huge_files);
4069         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4070
4071         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4072         if (ext4_has_feature_64bit(sb)) {
4073                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4074                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4075                     !is_power_of_2(sbi->s_desc_size)) {
4076                         ext4_msg(sb, KERN_ERR,
4077                                "unsupported descriptor size %lu",
4078                                sbi->s_desc_size);
4079                         goto failed_mount;
4080                 }
4081         } else
4082                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4083
4084         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4085         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4086
4087         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4088         if (sbi->s_inodes_per_block == 0)
4089                 goto cantfind_ext4;
4090         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4091             sbi->s_inodes_per_group > blocksize * 8) {
4092                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4093                          sbi->s_blocks_per_group);
4094                 goto failed_mount;
4095         }
4096         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4097                                         sbi->s_inodes_per_block;
4098         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4099         sbi->s_sbh = bh;
4100         sbi->s_mount_state = le16_to_cpu(es->s_state);
4101         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4102         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4103
4104         for (i = 0; i < 4; i++)
4105                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4106         sbi->s_def_hash_version = es->s_def_hash_version;
4107         if (ext4_has_feature_dir_index(sb)) {
4108                 i = le32_to_cpu(es->s_flags);
4109                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4110                         sbi->s_hash_unsigned = 3;
4111                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4112 #ifdef __CHAR_UNSIGNED__
4113                         if (!sb_rdonly(sb))
4114                                 es->s_flags |=
4115                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4116                         sbi->s_hash_unsigned = 3;
4117 #else
4118                         if (!sb_rdonly(sb))
4119                                 es->s_flags |=
4120                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4121 #endif
4122                 }
4123         }
4124
4125         /* Handle clustersize */
4126         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4127         has_bigalloc = ext4_has_feature_bigalloc(sb);
4128         if (has_bigalloc) {
4129                 if (clustersize < blocksize) {
4130                         ext4_msg(sb, KERN_ERR,
4131                                  "cluster size (%d) smaller than "
4132                                  "block size (%d)", clustersize, blocksize);
4133                         goto failed_mount;
4134                 }
4135                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4136                         le32_to_cpu(es->s_log_block_size);
4137                 sbi->s_clusters_per_group =
4138                         le32_to_cpu(es->s_clusters_per_group);
4139                 if (sbi->s_clusters_per_group > blocksize * 8) {
4140                         ext4_msg(sb, KERN_ERR,
4141                                  "#clusters per group too big: %lu",
4142                                  sbi->s_clusters_per_group);
4143                         goto failed_mount;
4144                 }
4145                 if (sbi->s_blocks_per_group !=
4146                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4147                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4148                                  "clusters per group (%lu) inconsistent",
4149                                  sbi->s_blocks_per_group,
4150                                  sbi->s_clusters_per_group);
4151                         goto failed_mount;
4152                 }
4153         } else {
4154                 if (clustersize != blocksize) {
4155                         ext4_msg(sb, KERN_ERR,
4156                                  "fragment/cluster size (%d) != "
4157                                  "block size (%d)", clustersize, blocksize);
4158                         goto failed_mount;
4159                 }
4160                 if (sbi->s_blocks_per_group > blocksize * 8) {
4161                         ext4_msg(sb, KERN_ERR,
4162                                  "#blocks per group too big: %lu",
4163                                  sbi->s_blocks_per_group);
4164                         goto failed_mount;
4165                 }
4166                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4167                 sbi->s_cluster_bits = 0;
4168         }
4169         sbi->s_cluster_ratio = clustersize / blocksize;
4170
4171         /* Do we have standard group size of clustersize * 8 blocks ? */
4172         if (sbi->s_blocks_per_group == clustersize << 3)
4173                 set_opt2(sb, STD_GROUP_SIZE);
4174
4175         /*
4176          * Test whether we have more sectors than will fit in sector_t,
4177          * and whether the max offset is addressable by the page cache.
4178          */
4179         err = generic_check_addressable(sb->s_blocksize_bits,
4180                                         ext4_blocks_count(es));
4181         if (err) {
4182                 ext4_msg(sb, KERN_ERR, "filesystem"
4183                          " too large to mount safely on this system");
4184                 goto failed_mount;
4185         }
4186
4187         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4188                 goto cantfind_ext4;
4189
4190         /* check blocks count against device size */
4191         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4192         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4193                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4194                        "exceeds size of device (%llu blocks)",
4195                        ext4_blocks_count(es), blocks_count);
4196                 goto failed_mount;
4197         }
4198
4199         /*
4200          * It makes no sense for the first data block to be beyond the end
4201          * of the filesystem.
4202          */
4203         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4204                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4205                          "block %u is beyond end of filesystem (%llu)",
4206                          le32_to_cpu(es->s_first_data_block),
4207                          ext4_blocks_count(es));
4208                 goto failed_mount;
4209         }
4210         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4211             (sbi->s_cluster_ratio == 1)) {
4212                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4213                          "block is 0 with a 1k block and cluster size");
4214                 goto failed_mount;
4215         }
4216
4217         blocks_count = (ext4_blocks_count(es) -
4218                         le32_to_cpu(es->s_first_data_block) +
4219                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4220         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4221         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4222                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
4223                        "(block count %llu, first data block %u, "
4224                        "blocks per group %lu)", sbi->s_groups_count,
4225                        ext4_blocks_count(es),
4226                        le32_to_cpu(es->s_first_data_block),
4227                        EXT4_BLOCKS_PER_GROUP(sb));
4228                 goto failed_mount;
4229         }
4230         sbi->s_groups_count = blocks_count;
4231         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4232                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4233         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4234             le32_to_cpu(es->s_inodes_count)) {
4235                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4236                          le32_to_cpu(es->s_inodes_count),
4237                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4238                 ret = -EINVAL;
4239                 goto failed_mount;
4240         }
4241         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4242                    EXT4_DESC_PER_BLOCK(sb);
4243         if (ext4_has_feature_meta_bg(sb)) {
4244                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4245                         ext4_msg(sb, KERN_WARNING,
4246                                  "first meta block group too large: %u "
4247                                  "(group descriptor block count %u)",
4248                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4249                         goto failed_mount;
4250                 }
4251         }
4252         sbi->s_group_desc = kvmalloc_array(db_count,
4253                                            sizeof(struct buffer_head *),
4254                                            GFP_KERNEL);
4255         if (sbi->s_group_desc == NULL) {
4256                 ext4_msg(sb, KERN_ERR, "not enough memory");
4257                 ret = -ENOMEM;
4258                 goto failed_mount;
4259         }
4260
4261         bgl_lock_init(sbi->s_blockgroup_lock);
4262
4263         /* Pre-read the descriptors into the buffer cache */
4264         for (i = 0; i < db_count; i++) {
4265                 block = descriptor_loc(sb, logical_sb_block, i);
4266                 sb_breadahead(sb, block);
4267         }
4268
4269         for (i = 0; i < db_count; i++) {
4270                 block = descriptor_loc(sb, logical_sb_block, i);
4271                 sbi->s_group_desc[i] = sb_bread_unmovable(sb, block);
4272                 if (!sbi->s_group_desc[i]) {
4273                         ext4_msg(sb, KERN_ERR,
4274                                "can't read group descriptor %d", i);
4275                         db_count = i;
4276                         goto failed_mount2;
4277                 }
4278         }
4279         sbi->s_gdb_count = db_count;
4280         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4281                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4282                 ret = -EFSCORRUPTED;
4283                 goto failed_mount2;
4284         }
4285
4286         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4287
4288         /* Register extent status tree shrinker */
4289         if (ext4_es_register_shrinker(sbi))
4290                 goto failed_mount3;
4291
4292         sbi->s_stripe = ext4_get_stripe_size(sbi);
4293         sbi->s_extent_max_zeroout_kb = 32;
4294
4295         /*
4296          * set up enough so that it can read an inode
4297          */
4298         sb->s_op = &ext4_sops;
4299         sb->s_export_op = &ext4_export_ops;
4300         sb->s_xattr = ext4_xattr_handlers;
4301 #ifdef CONFIG_FS_ENCRYPTION
4302         sb->s_cop = &ext4_cryptops;
4303 #endif
4304 #ifdef CONFIG_FS_VERITY
4305         sb->s_vop = &ext4_verityops;
4306 #endif
4307 #ifdef CONFIG_QUOTA
4308         sb->dq_op = &ext4_quota_operations;
4309         if (ext4_has_feature_quota(sb))
4310                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4311         else
4312                 sb->s_qcop = &ext4_qctl_operations;
4313         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4314 #endif
4315         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4316
4317         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4318         mutex_init(&sbi->s_orphan_lock);
4319
4320         sb->s_root = NULL;
4321
4322         needs_recovery = (es->s_last_orphan != 0 ||
4323                           ext4_has_feature_journal_needs_recovery(sb));
4324
4325         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4326                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4327                         goto failed_mount3a;
4328
4329         /*
4330          * The first inode we look at is the journal inode.  Don't try
4331          * root first: it may be modified in the journal!
4332          */
4333         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4334                 err = ext4_load_journal(sb, es, journal_devnum);
4335                 if (err)
4336                         goto failed_mount3a;
4337         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4338                    ext4_has_feature_journal_needs_recovery(sb)) {
4339                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4340                        "suppressed and not mounted read-only");
4341                 goto failed_mount_wq;
4342         } else {
4343                 /* Nojournal mode, all journal mount options are illegal */
4344                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4345                         ext4_msg(sb, KERN_ERR, "can't mount with "
4346                                  "journal_checksum, fs mounted w/o journal");
4347                         goto failed_mount_wq;
4348                 }
4349                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4350                         ext4_msg(sb, KERN_ERR, "can't mount with "
4351                                  "journal_async_commit, fs mounted w/o journal");
4352                         goto failed_mount_wq;
4353                 }
4354                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4355                         ext4_msg(sb, KERN_ERR, "can't mount with "
4356                                  "commit=%lu, fs mounted w/o journal",
4357                                  sbi->s_commit_interval / HZ);
4358                         goto failed_mount_wq;
4359                 }
4360                 if (EXT4_MOUNT_DATA_FLAGS &
4361                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4362                         ext4_msg(sb, KERN_ERR, "can't mount with "
4363                                  "data=, fs mounted w/o journal");
4364                         goto failed_mount_wq;
4365                 }
4366                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4367                 clear_opt(sb, JOURNAL_CHECKSUM);
4368                 clear_opt(sb, DATA_FLAGS);
4369                 sbi->s_journal = NULL;
4370                 needs_recovery = 0;
4371                 goto no_journal;
4372         }
4373
4374         if (ext4_has_feature_64bit(sb) &&
4375             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4376                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4377                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4378                 goto failed_mount_wq;
4379         }
4380
4381         if (!set_journal_csum_feature_set(sb)) {
4382                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4383                          "feature set");
4384                 goto failed_mount_wq;
4385         }
4386
4387         /* We have now updated the journal if required, so we can
4388          * validate the data journaling mode. */
4389         switch (test_opt(sb, DATA_FLAGS)) {
4390         case 0:
4391                 /* No mode set, assume a default based on the journal
4392                  * capabilities: ORDERED_DATA if the journal can
4393                  * cope, else JOURNAL_DATA
4394                  */
4395                 if (jbd2_journal_check_available_features
4396                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4397                         set_opt(sb, ORDERED_DATA);
4398                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4399                 } else {
4400                         set_opt(sb, JOURNAL_DATA);
4401                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4402                 }
4403                 break;
4404
4405         case EXT4_MOUNT_ORDERED_DATA:
4406         case EXT4_MOUNT_WRITEBACK_DATA:
4407                 if (!jbd2_journal_check_available_features
4408                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4409                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4410                                "requested data journaling mode");
4411                         goto failed_mount_wq;
4412                 }
4413         default:
4414                 break;
4415         }
4416
4417         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4418             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4419                 ext4_msg(sb, KERN_ERR, "can't mount with "
4420                         "journal_async_commit in data=ordered mode");
4421                 goto failed_mount_wq;
4422         }
4423
4424         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4425
4426         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4427
4428 no_journal:
4429         if (!test_opt(sb, NO_MBCACHE)) {
4430                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4431                 if (!sbi->s_ea_block_cache) {
4432                         ext4_msg(sb, KERN_ERR,
4433                                  "Failed to create ea_block_cache");
4434                         goto failed_mount_wq;
4435                 }
4436
4437                 if (ext4_has_feature_ea_inode(sb)) {
4438                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4439                         if (!sbi->s_ea_inode_cache) {
4440                                 ext4_msg(sb, KERN_ERR,
4441                                          "Failed to create ea_inode_cache");
4442                                 goto failed_mount_wq;
4443                         }
4444                 }
4445         }
4446
4447         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4448                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4449                 goto failed_mount_wq;
4450         }
4451
4452         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4453             !ext4_has_feature_encrypt(sb)) {
4454                 ext4_set_feature_encrypt(sb);
4455                 ext4_commit_super(sb, 1);
4456         }
4457
4458         /*
4459          * Get the # of file system overhead blocks from the
4460          * superblock if present.
4461          */
4462         if (es->s_overhead_clusters)
4463                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4464         else {
4465                 err = ext4_calculate_overhead(sb);
4466                 if (err)
4467                         goto failed_mount_wq;
4468         }
4469
4470         /*
4471          * The maximum number of concurrent works can be high and
4472          * concurrency isn't really necessary.  Limit it to 1.
4473          */
4474         EXT4_SB(sb)->rsv_conversion_wq =
4475                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4476         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4477                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4478                 ret = -ENOMEM;
4479                 goto failed_mount4;
4480         }
4481
4482         /*
4483          * The jbd2_journal_load will have done any necessary log recovery,
4484          * so we can safely mount the rest of the filesystem now.
4485          */
4486
4487         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4488         if (IS_ERR(root)) {
4489                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4490                 ret = PTR_ERR(root);
4491                 root = NULL;
4492                 goto failed_mount4;
4493         }
4494         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4495                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4496                 iput(root);
4497                 goto failed_mount4;
4498         }
4499
4500 #ifdef CONFIG_UNICODE
4501         if (sbi->s_encoding)
4502                 sb->s_d_op = &ext4_dentry_ops;
4503 #endif
4504
4505         sb->s_root = d_make_root(root);
4506         if (!sb->s_root) {
4507                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4508                 ret = -ENOMEM;
4509                 goto failed_mount4;
4510         }
4511
4512         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4513         if (ret == -EROFS) {
4514                 sb->s_flags |= SB_RDONLY;
4515                 ret = 0;
4516         } else if (ret)
4517                 goto failed_mount4a;
4518
4519         ext4_set_resv_clusters(sb);
4520
4521         err = ext4_setup_system_zone(sb);
4522         if (err) {
4523                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4524                          "zone (%d)", err);
4525                 goto failed_mount4a;
4526         }
4527
4528         ext4_ext_init(sb);
4529         err = ext4_mb_init(sb);
4530         if (err) {
4531                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4532                          err);
4533                 goto failed_mount5;
4534         }
4535
4536         block = ext4_count_free_clusters(sb);
4537         ext4_free_blocks_count_set(sbi->s_es, 
4538                                    EXT4_C2B(sbi, block));
4539         ext4_superblock_csum_set(sb);
4540         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4541                                   GFP_KERNEL);
4542         if (!err) {
4543                 unsigned long freei = ext4_count_free_inodes(sb);
4544                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4545                 ext4_superblock_csum_set(sb);
4546                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4547                                           GFP_KERNEL);
4548         }
4549         if (!err)
4550                 err = percpu_counter_init(&sbi->s_dirs_counter,
4551                                           ext4_count_dirs(sb), GFP_KERNEL);
4552         if (!err)
4553                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4554                                           GFP_KERNEL);
4555         if (!err)
4556                 err = percpu_init_rwsem(&sbi->s_journal_flag_rwsem);
4557
4558         if (err) {
4559                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4560                 goto failed_mount6;
4561         }
4562
4563         if (ext4_has_feature_flex_bg(sb))
4564                 if (!ext4_fill_flex_info(sb)) {
4565                         ext4_msg(sb, KERN_ERR,
4566                                "unable to initialize "
4567                                "flex_bg meta info!");
4568                         goto failed_mount6;
4569                 }
4570
4571         err = ext4_register_li_request(sb, first_not_zeroed);
4572         if (err)
4573                 goto failed_mount6;
4574
4575         err = ext4_register_sysfs(sb);
4576         if (err)
4577                 goto failed_mount7;
4578
4579 #ifdef CONFIG_QUOTA
4580         /* Enable quota usage during mount. */
4581         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
4582                 err = ext4_enable_quotas(sb);
4583                 if (err)
4584                         goto failed_mount8;
4585         }
4586 #endif  /* CONFIG_QUOTA */
4587
4588         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4589         ext4_orphan_cleanup(sb, es);
4590         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4591         if (needs_recovery) {
4592                 ext4_msg(sb, KERN_INFO, "recovery complete");
4593                 ext4_mark_recovery_complete(sb, es);
4594         }
4595         if (EXT4_SB(sb)->s_journal) {
4596                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4597                         descr = " journalled data mode";
4598                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4599                         descr = " ordered data mode";
4600                 else
4601                         descr = " writeback data mode";
4602         } else
4603                 descr = "out journal";
4604
4605         if (test_opt(sb, DISCARD)) {
4606                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4607                 if (!blk_queue_discard(q))
4608                         ext4_msg(sb, KERN_WARNING,
4609                                  "mounting with \"discard\" option, but "
4610                                  "the device does not support discard");
4611         }
4612
4613         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4614                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4615                          "Opts: %.*s%s%s", descr,
4616                          (int) sizeof(sbi->s_es->s_mount_opts),
4617                          sbi->s_es->s_mount_opts,
4618                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4619
4620         if (es->s_error_count)
4621                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4622
4623         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4624         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4625         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4626         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4627
4628         kfree(orig_data);
4629         return 0;
4630
4631 cantfind_ext4:
4632         if (!silent)
4633                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4634         goto failed_mount;
4635
4636 #ifdef CONFIG_QUOTA
4637 failed_mount8:
4638         ext4_unregister_sysfs(sb);
4639 #endif
4640 failed_mount7:
4641         ext4_unregister_li_request(sb);
4642 failed_mount6:
4643         ext4_mb_release(sb);
4644         if (sbi->s_flex_groups)
4645                 kvfree(sbi->s_flex_groups);
4646         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4647         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4648         percpu_counter_destroy(&sbi->s_dirs_counter);
4649         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4650         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
4651 failed_mount5:
4652         ext4_ext_release(sb);
4653         ext4_release_system_zone(sb);
4654 failed_mount4a:
4655         dput(sb->s_root);
4656         sb->s_root = NULL;
4657 failed_mount4:
4658         ext4_msg(sb, KERN_ERR, "mount failed");
4659         if (EXT4_SB(sb)->rsv_conversion_wq)
4660                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4661 failed_mount_wq:
4662         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
4663         sbi->s_ea_inode_cache = NULL;
4664
4665         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
4666         sbi->s_ea_block_cache = NULL;
4667
4668         if (sbi->s_journal) {
4669                 jbd2_journal_destroy(sbi->s_journal);
4670                 sbi->s_journal = NULL;
4671         }
4672 failed_mount3a:
4673         ext4_es_unregister_shrinker(sbi);
4674 failed_mount3:
4675         del_timer_sync(&sbi->s_err_report);
4676         if (sbi->s_mmp_tsk)
4677                 kthread_stop(sbi->s_mmp_tsk);
4678 failed_mount2:
4679         for (i = 0; i < db_count; i++)
4680                 brelse(sbi->s_group_desc[i]);
4681         kvfree(sbi->s_group_desc);
4682 failed_mount:
4683         if (sbi->s_chksum_driver)
4684                 crypto_free_shash(sbi->s_chksum_driver);
4685
4686 #ifdef CONFIG_UNICODE
4687         utf8_unload(sbi->s_encoding);
4688 #endif
4689
4690 #ifdef CONFIG_QUOTA
4691         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4692                 kfree(get_qf_name(sb, sbi, i));
4693 #endif
4694         ext4_blkdev_remove(sbi);
4695         brelse(bh);
4696 out_fail:
4697         sb->s_fs_info = NULL;
4698         kfree(sbi->s_blockgroup_lock);
4699 out_free_base:
4700         kfree(sbi);
4701         kfree(orig_data);
4702         fs_put_dax(dax_dev);
4703         return err ? err : ret;
4704 }
4705
4706 /*
4707  * Setup any per-fs journal parameters now.  We'll do this both on
4708  * initial mount, once the journal has been initialised but before we've
4709  * done any recovery; and again on any subsequent remount.
4710  */
4711 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4712 {
4713         struct ext4_sb_info *sbi = EXT4_SB(sb);
4714
4715         journal->j_commit_interval = sbi->s_commit_interval;
4716         journal->j_min_batch_time = sbi->s_min_batch_time;
4717         journal->j_max_batch_time = sbi->s_max_batch_time;
4718
4719         write_lock(&journal->j_state_lock);
4720         if (test_opt(sb, BARRIER))
4721                 journal->j_flags |= JBD2_BARRIER;
4722         else
4723                 journal->j_flags &= ~JBD2_BARRIER;
4724         if (test_opt(sb, DATA_ERR_ABORT))
4725                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4726         else
4727                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4728         write_unlock(&journal->j_state_lock);
4729 }
4730
4731 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4732                                              unsigned int journal_inum)
4733 {
4734         struct inode *journal_inode;
4735
4736         /*
4737          * Test for the existence of a valid inode on disk.  Bad things
4738          * happen if we iget() an unused inode, as the subsequent iput()
4739          * will try to delete it.
4740          */
4741         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4742         if (IS_ERR(journal_inode)) {
4743                 ext4_msg(sb, KERN_ERR, "no journal found");
4744                 return NULL;
4745         }
4746         if (!journal_inode->i_nlink) {
4747                 make_bad_inode(journal_inode);
4748                 iput(journal_inode);
4749                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4750                 return NULL;
4751         }
4752
4753         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4754                   journal_inode, journal_inode->i_size);
4755         if (!S_ISREG(journal_inode->i_mode)) {
4756                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4757                 iput(journal_inode);
4758                 return NULL;
4759         }
4760         return journal_inode;
4761 }
4762
4763 static journal_t *ext4_get_journal(struct super_block *sb,
4764                                    unsigned int journal_inum)
4765 {
4766         struct inode *journal_inode;
4767         journal_t *journal;
4768
4769         BUG_ON(!ext4_has_feature_journal(sb));
4770
4771         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4772         if (!journal_inode)
4773                 return NULL;
4774
4775         journal = jbd2_journal_init_inode(journal_inode);
4776         if (!journal) {
4777                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4778                 iput(journal_inode);
4779                 return NULL;
4780         }
4781         journal->j_private = sb;
4782         ext4_init_journal_params(sb, journal);
4783         return journal;
4784 }
4785
4786 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4787                                        dev_t j_dev)
4788 {
4789         struct buffer_head *bh;
4790         journal_t *journal;
4791         ext4_fsblk_t start;
4792         ext4_fsblk_t len;
4793         int hblock, blocksize;
4794         ext4_fsblk_t sb_block;
4795         unsigned long offset;
4796         struct ext4_super_block *es;
4797         struct block_device *bdev;
4798
4799         BUG_ON(!ext4_has_feature_journal(sb));
4800
4801         bdev = ext4_blkdev_get(j_dev, sb);
4802         if (bdev == NULL)
4803                 return NULL;
4804
4805         blocksize = sb->s_blocksize;
4806         hblock = bdev_logical_block_size(bdev);
4807         if (blocksize < hblock) {
4808                 ext4_msg(sb, KERN_ERR,
4809                         "blocksize too small for journal device");
4810                 goto out_bdev;
4811         }
4812
4813         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4814         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4815         set_blocksize(bdev, blocksize);
4816         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4817                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4818                        "external journal");
4819                 goto out_bdev;
4820         }
4821
4822         es = (struct ext4_super_block *) (bh->b_data + offset);
4823         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4824             !(le32_to_cpu(es->s_feature_incompat) &
4825               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4826                 ext4_msg(sb, KERN_ERR, "external journal has "
4827                                         "bad superblock");
4828                 brelse(bh);
4829                 goto out_bdev;
4830         }
4831
4832         if ((le32_to_cpu(es->s_feature_ro_compat) &
4833              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4834             es->s_checksum != ext4_superblock_csum(sb, es)) {
4835                 ext4_msg(sb, KERN_ERR, "external journal has "
4836                                        "corrupt superblock");
4837                 brelse(bh);
4838                 goto out_bdev;
4839         }
4840
4841         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4842                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4843                 brelse(bh);
4844                 goto out_bdev;
4845         }
4846
4847         len = ext4_blocks_count(es);
4848         start = sb_block + 1;
4849         brelse(bh);     /* we're done with the superblock */
4850
4851         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4852                                         start, len, blocksize);
4853         if (!journal) {
4854                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4855                 goto out_bdev;
4856         }
4857         journal->j_private = sb;
4858         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4859         wait_on_buffer(journal->j_sb_buffer);
4860         if (!buffer_uptodate(journal->j_sb_buffer)) {
4861                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4862                 goto out_journal;
4863         }
4864         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4865                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4866                                         "user (unsupported) - %d",
4867                         be32_to_cpu(journal->j_superblock->s_nr_users));
4868                 goto out_journal;
4869         }
4870         EXT4_SB(sb)->journal_bdev = bdev;
4871         ext4_init_journal_params(sb, journal);
4872         return journal;
4873
4874 out_journal:
4875         jbd2_journal_destroy(journal);
4876 out_bdev:
4877         ext4_blkdev_put(bdev);
4878         return NULL;
4879 }
4880
4881 static int ext4_load_journal(struct super_block *sb,
4882                              struct ext4_super_block *es,
4883                              unsigned long journal_devnum)
4884 {
4885         journal_t *journal;
4886         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4887         dev_t journal_dev;
4888         int err = 0;
4889         int really_read_only;
4890
4891         BUG_ON(!ext4_has_feature_journal(sb));
4892
4893         if (journal_devnum &&
4894             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4895                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4896                         "numbers have changed");
4897                 journal_dev = new_decode_dev(journal_devnum);
4898         } else
4899                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4900
4901         really_read_only = bdev_read_only(sb->s_bdev);
4902
4903         /*
4904          * Are we loading a blank journal or performing recovery after a
4905          * crash?  For recovery, we need to check in advance whether we
4906          * can get read-write access to the device.
4907          */
4908         if (ext4_has_feature_journal_needs_recovery(sb)) {
4909                 if (sb_rdonly(sb)) {
4910                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4911                                         "required on readonly filesystem");
4912                         if (really_read_only) {
4913                                 ext4_msg(sb, KERN_ERR, "write access "
4914                                         "unavailable, cannot proceed "
4915                                         "(try mounting with noload)");
4916                                 return -EROFS;
4917                         }
4918                         ext4_msg(sb, KERN_INFO, "write access will "
4919                                "be enabled during recovery");
4920                 }
4921         }
4922
4923         if (journal_inum && journal_dev) {
4924                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4925                        "and inode journals!");
4926                 return -EINVAL;
4927         }
4928
4929         if (journal_inum) {
4930                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4931                         return -EINVAL;
4932         } else {
4933                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4934                         return -EINVAL;
4935         }
4936
4937         if (!(journal->j_flags & JBD2_BARRIER))
4938                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4939
4940         if (!ext4_has_feature_journal_needs_recovery(sb))
4941                 err = jbd2_journal_wipe(journal, !really_read_only);
4942         if (!err) {
4943                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4944                 if (save)
4945                         memcpy(save, ((char *) es) +
4946                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4947                 err = jbd2_journal_load(journal);
4948                 if (save)
4949                         memcpy(((char *) es) + EXT4_S_ERR_START,
4950                                save, EXT4_S_ERR_LEN);
4951                 kfree(save);
4952         }
4953
4954         if (err) {
4955                 ext4_msg(sb, KERN_ERR, "error loading journal");
4956                 jbd2_journal_destroy(journal);
4957                 return err;
4958         }
4959
4960         EXT4_SB(sb)->s_journal = journal;
4961         ext4_clear_journal_err(sb, es);
4962
4963         if (!really_read_only && journal_devnum &&
4964             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4965                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4966
4967                 /* Make sure we flush the recovery flag to disk. */
4968                 ext4_commit_super(sb, 1);
4969         }
4970
4971         return 0;
4972 }
4973
4974 static int ext4_commit_super(struct super_block *sb, int sync)
4975 {
4976         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4977         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4978         int error = 0;
4979
4980         if (!sbh || block_device_ejected(sb))
4981                 return error;
4982
4983         /*
4984          * The superblock bh should be mapped, but it might not be if the
4985          * device was hot-removed. Not much we can do but fail the I/O.
4986          */
4987         if (!buffer_mapped(sbh))
4988                 return error;
4989
4990         /*
4991          * If the file system is mounted read-only, don't update the
4992          * superblock write time.  This avoids updating the superblock
4993          * write time when we are mounting the root file system
4994          * read/only but we need to replay the journal; at that point,
4995          * for people who are east of GMT and who make their clock
4996          * tick in localtime for Windows bug-for-bug compatibility,
4997          * the clock is set in the future, and this will cause e2fsck
4998          * to complain and force a full file system check.
4999          */
5000         if (!(sb->s_flags & SB_RDONLY))
5001                 ext4_update_tstamp(es, s_wtime);
5002         if (sb->s_bdev->bd_part)
5003                 es->s_kbytes_written =
5004                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5005                             ((part_stat_read(sb->s_bdev->bd_part,
5006                                              sectors[STAT_WRITE]) -
5007                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5008         else
5009                 es->s_kbytes_written =
5010                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5011         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5012                 ext4_free_blocks_count_set(es,
5013                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5014                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5015         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5016                 es->s_free_inodes_count =
5017                         cpu_to_le32(percpu_counter_sum_positive(
5018                                 &EXT4_SB(sb)->s_freeinodes_counter));
5019         BUFFER_TRACE(sbh, "marking dirty");
5020         ext4_superblock_csum_set(sb);
5021         if (sync)
5022                 lock_buffer(sbh);
5023         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5024                 /*
5025                  * Oh, dear.  A previous attempt to write the
5026                  * superblock failed.  This could happen because the
5027                  * USB device was yanked out.  Or it could happen to
5028                  * be a transient write error and maybe the block will
5029                  * be remapped.  Nothing we can do but to retry the
5030                  * write and hope for the best.
5031                  */
5032                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5033                        "superblock detected");
5034                 clear_buffer_write_io_error(sbh);
5035                 set_buffer_uptodate(sbh);
5036         }
5037         mark_buffer_dirty(sbh);
5038         if (sync) {
5039                 unlock_buffer(sbh);
5040                 error = __sync_dirty_buffer(sbh,
5041                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5042                 if (buffer_write_io_error(sbh)) {
5043                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5044                                "superblock");
5045                         clear_buffer_write_io_error(sbh);
5046                         set_buffer_uptodate(sbh);
5047                 }
5048         }
5049         return error;
5050 }
5051
5052 /*
5053  * Have we just finished recovery?  If so, and if we are mounting (or
5054  * remounting) the filesystem readonly, then we will end up with a
5055  * consistent fs on disk.  Record that fact.
5056  */
5057 static void ext4_mark_recovery_complete(struct super_block *sb,
5058                                         struct ext4_super_block *es)
5059 {
5060         journal_t *journal = EXT4_SB(sb)->s_journal;
5061
5062         if (!ext4_has_feature_journal(sb)) {
5063                 BUG_ON(journal != NULL);
5064                 return;
5065         }
5066         jbd2_journal_lock_updates(journal);
5067         if (jbd2_journal_flush(journal) < 0)
5068                 goto out;
5069
5070         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5071                 ext4_clear_feature_journal_needs_recovery(sb);
5072                 ext4_commit_super(sb, 1);
5073         }
5074
5075 out:
5076         jbd2_journal_unlock_updates(journal);
5077 }
5078
5079 /*
5080  * If we are mounting (or read-write remounting) a filesystem whose journal
5081  * has recorded an error from a previous lifetime, move that error to the
5082  * main filesystem now.
5083  */
5084 static void ext4_clear_journal_err(struct super_block *sb,
5085                                    struct ext4_super_block *es)
5086 {
5087         journal_t *journal;
5088         int j_errno;
5089         const char *errstr;
5090
5091         BUG_ON(!ext4_has_feature_journal(sb));
5092
5093         journal = EXT4_SB(sb)->s_journal;
5094
5095         /*
5096          * Now check for any error status which may have been recorded in the
5097          * journal by a prior ext4_error() or ext4_abort()
5098          */
5099
5100         j_errno = jbd2_journal_errno(journal);
5101         if (j_errno) {
5102                 char nbuf[16];
5103
5104                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5105                 ext4_warning(sb, "Filesystem error recorded "
5106                              "from previous mount: %s", errstr);
5107                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5108
5109                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5110                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5111                 ext4_commit_super(sb, 1);
5112
5113                 jbd2_journal_clear_err(journal);
5114                 jbd2_journal_update_sb_errno(journal);
5115         }
5116 }
5117
5118 /*
5119  * Force the running and committing transactions to commit,
5120  * and wait on the commit.
5121  */
5122 int ext4_force_commit(struct super_block *sb)
5123 {
5124         journal_t *journal;
5125
5126         if (sb_rdonly(sb))
5127                 return 0;
5128
5129         journal = EXT4_SB(sb)->s_journal;
5130         return ext4_journal_force_commit(journal);
5131 }
5132
5133 static int ext4_sync_fs(struct super_block *sb, int wait)
5134 {
5135         int ret = 0;
5136         tid_t target;
5137         bool needs_barrier = false;
5138         struct ext4_sb_info *sbi = EXT4_SB(sb);
5139
5140         if (unlikely(ext4_forced_shutdown(sbi)))
5141                 return 0;
5142
5143         trace_ext4_sync_fs(sb, wait);
5144         flush_workqueue(sbi->rsv_conversion_wq);
5145         /*
5146          * Writeback quota in non-journalled quota case - journalled quota has
5147          * no dirty dquots
5148          */
5149         dquot_writeback_dquots(sb, -1);
5150         /*
5151          * Data writeback is possible w/o journal transaction, so barrier must
5152          * being sent at the end of the function. But we can skip it if
5153          * transaction_commit will do it for us.
5154          */
5155         if (sbi->s_journal) {
5156                 target = jbd2_get_latest_transaction(sbi->s_journal);
5157                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5158                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5159                         needs_barrier = true;
5160
5161                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5162                         if (wait)
5163                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5164                                                            target);
5165                 }
5166         } else if (wait && test_opt(sb, BARRIER))
5167                 needs_barrier = true;
5168         if (needs_barrier) {
5169                 int err;
5170                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
5171                 if (!ret)
5172                         ret = err;
5173         }
5174
5175         return ret;
5176 }
5177
5178 /*
5179  * LVM calls this function before a (read-only) snapshot is created.  This
5180  * gives us a chance to flush the journal completely and mark the fs clean.
5181  *
5182  * Note that only this function cannot bring a filesystem to be in a clean
5183  * state independently. It relies on upper layer to stop all data & metadata
5184  * modifications.
5185  */
5186 static int ext4_freeze(struct super_block *sb)
5187 {
5188         int error = 0;
5189         journal_t *journal;
5190
5191         if (sb_rdonly(sb))
5192                 return 0;
5193
5194         journal = EXT4_SB(sb)->s_journal;
5195
5196         if (journal) {
5197                 /* Now we set up the journal barrier. */
5198                 jbd2_journal_lock_updates(journal);
5199
5200                 /*
5201                  * Don't clear the needs_recovery flag if we failed to
5202                  * flush the journal.
5203                  */
5204                 error = jbd2_journal_flush(journal);
5205                 if (error < 0)
5206                         goto out;
5207
5208                 /* Journal blocked and flushed, clear needs_recovery flag. */
5209                 ext4_clear_feature_journal_needs_recovery(sb);
5210         }
5211
5212         error = ext4_commit_super(sb, 1);
5213 out:
5214         if (journal)
5215                 /* we rely on upper layer to stop further updates */
5216                 jbd2_journal_unlock_updates(journal);
5217         return error;
5218 }
5219
5220 /*
5221  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5222  * flag here, even though the filesystem is not technically dirty yet.
5223  */
5224 static int ext4_unfreeze(struct super_block *sb)
5225 {
5226         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5227                 return 0;
5228
5229         if (EXT4_SB(sb)->s_journal) {
5230                 /* Reset the needs_recovery flag before the fs is unlocked. */
5231                 ext4_set_feature_journal_needs_recovery(sb);
5232         }
5233
5234         ext4_commit_super(sb, 1);
5235         return 0;
5236 }
5237
5238 /*
5239  * Structure to save mount options for ext4_remount's benefit
5240  */
5241 struct ext4_mount_options {
5242         unsigned long s_mount_opt;
5243         unsigned long s_mount_opt2;
5244         kuid_t s_resuid;
5245         kgid_t s_resgid;
5246         unsigned long s_commit_interval;
5247         u32 s_min_batch_time, s_max_batch_time;
5248 #ifdef CONFIG_QUOTA
5249         int s_jquota_fmt;
5250         char *s_qf_names[EXT4_MAXQUOTAS];
5251 #endif
5252 };
5253
5254 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5255 {
5256         struct ext4_super_block *es;
5257         struct ext4_sb_info *sbi = EXT4_SB(sb);
5258         unsigned long old_sb_flags;
5259         struct ext4_mount_options old_opts;
5260         int enable_quota = 0;
5261         ext4_group_t g;
5262         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5263         int err = 0;
5264 #ifdef CONFIG_QUOTA
5265         int i, j;
5266         char *to_free[EXT4_MAXQUOTAS];
5267 #endif
5268         char *orig_data = kstrdup(data, GFP_KERNEL);
5269
5270         if (data && !orig_data)
5271                 return -ENOMEM;
5272
5273         /* Store the original options */
5274         old_sb_flags = sb->s_flags;
5275         old_opts.s_mount_opt = sbi->s_mount_opt;
5276         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5277         old_opts.s_resuid = sbi->s_resuid;
5278         old_opts.s_resgid = sbi->s_resgid;
5279         old_opts.s_commit_interval = sbi->s_commit_interval;
5280         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5281         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5282 #ifdef CONFIG_QUOTA
5283         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5284         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5285                 if (sbi->s_qf_names[i]) {
5286                         char *qf_name = get_qf_name(sb, sbi, i);
5287
5288                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5289                         if (!old_opts.s_qf_names[i]) {
5290                                 for (j = 0; j < i; j++)
5291                                         kfree(old_opts.s_qf_names[j]);
5292                                 kfree(orig_data);
5293                                 return -ENOMEM;
5294                         }
5295                 } else
5296                         old_opts.s_qf_names[i] = NULL;
5297 #endif
5298         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5299                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5300
5301         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5302                 err = -EINVAL;
5303                 goto restore_opts;
5304         }
5305
5306         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5307             test_opt(sb, JOURNAL_CHECKSUM)) {
5308                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5309                          "during remount not supported; ignoring");
5310                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5311         }
5312
5313         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5314                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5315                         ext4_msg(sb, KERN_ERR, "can't mount with "
5316                                  "both data=journal and delalloc");
5317                         err = -EINVAL;
5318                         goto restore_opts;
5319                 }
5320                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5321                         ext4_msg(sb, KERN_ERR, "can't mount with "
5322                                  "both data=journal and dioread_nolock");
5323                         err = -EINVAL;
5324                         goto restore_opts;
5325                 }
5326                 if (test_opt(sb, DAX)) {
5327                         ext4_msg(sb, KERN_ERR, "can't mount with "
5328                                  "both data=journal and dax");
5329                         err = -EINVAL;
5330                         goto restore_opts;
5331                 }
5332         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5333                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5334                         ext4_msg(sb, KERN_ERR, "can't mount with "
5335                                 "journal_async_commit in data=ordered mode");
5336                         err = -EINVAL;
5337                         goto restore_opts;
5338                 }
5339         }
5340
5341         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5342                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5343                 err = -EINVAL;
5344                 goto restore_opts;
5345         }
5346
5347         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5348                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5349                         "dax flag with busy inodes while remounting");
5350                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5351         }
5352
5353         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5354                 ext4_abort(sb, "Abort forced by user");
5355
5356         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5357                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5358
5359         es = sbi->s_es;
5360
5361         if (sbi->s_journal) {
5362                 ext4_init_journal_params(sb, sbi->s_journal);
5363                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5364         }
5365
5366         if (*flags & SB_LAZYTIME)
5367                 sb->s_flags |= SB_LAZYTIME;
5368
5369         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5370                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5371                         err = -EROFS;
5372                         goto restore_opts;
5373                 }
5374
5375                 if (*flags & SB_RDONLY) {
5376                         err = sync_filesystem(sb);
5377                         if (err < 0)
5378                                 goto restore_opts;
5379                         err = dquot_suspend(sb, -1);
5380                         if (err < 0)
5381                                 goto restore_opts;
5382
5383                         /*
5384                          * First of all, the unconditional stuff we have to do
5385                          * to disable replay of the journal when we next remount
5386                          */
5387                         sb->s_flags |= SB_RDONLY;
5388
5389                         /*
5390                          * OK, test if we are remounting a valid rw partition
5391                          * readonly, and if so set the rdonly flag and then
5392                          * mark the partition as valid again.
5393                          */
5394                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5395                             (sbi->s_mount_state & EXT4_VALID_FS))
5396                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5397
5398                         if (sbi->s_journal)
5399                                 ext4_mark_recovery_complete(sb, es);
5400                         if (sbi->s_mmp_tsk)
5401                                 kthread_stop(sbi->s_mmp_tsk);
5402                 } else {
5403                         /* Make sure we can mount this feature set readwrite */
5404                         if (ext4_has_feature_readonly(sb) ||
5405                             !ext4_feature_set_ok(sb, 0)) {
5406                                 err = -EROFS;
5407                                 goto restore_opts;
5408                         }
5409                         /*
5410                          * Make sure the group descriptor checksums
5411                          * are sane.  If they aren't, refuse to remount r/w.
5412                          */
5413                         for (g = 0; g < sbi->s_groups_count; g++) {
5414                                 struct ext4_group_desc *gdp =
5415                                         ext4_get_group_desc(sb, g, NULL);
5416
5417                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5418                                         ext4_msg(sb, KERN_ERR,
5419                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5420                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5421                                                le16_to_cpu(gdp->bg_checksum));
5422                                         err = -EFSBADCRC;
5423                                         goto restore_opts;
5424                                 }
5425                         }
5426
5427                         /*
5428                          * If we have an unprocessed orphan list hanging
5429                          * around from a previously readonly bdev mount,
5430                          * require a full umount/remount for now.
5431                          */
5432                         if (es->s_last_orphan) {
5433                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5434                                        "remount RDWR because of unprocessed "
5435                                        "orphan inode list.  Please "
5436                                        "umount/remount instead");
5437                                 err = -EINVAL;
5438                                 goto restore_opts;
5439                         }
5440
5441                         /*
5442                          * Mounting a RDONLY partition read-write, so reread
5443                          * and store the current valid flag.  (It may have
5444                          * been changed by e2fsck since we originally mounted
5445                          * the partition.)
5446                          */
5447                         if (sbi->s_journal)
5448                                 ext4_clear_journal_err(sb, es);
5449                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5450
5451                         err = ext4_setup_super(sb, es, 0);
5452                         if (err)
5453                                 goto restore_opts;
5454
5455                         sb->s_flags &= ~SB_RDONLY;
5456                         if (ext4_has_feature_mmp(sb))
5457                                 if (ext4_multi_mount_protect(sb,
5458                                                 le64_to_cpu(es->s_mmp_block))) {
5459                                         err = -EROFS;
5460                                         goto restore_opts;
5461                                 }
5462                         enable_quota = 1;
5463                 }
5464         }
5465
5466         /*
5467          * Reinitialize lazy itable initialization thread based on
5468          * current settings
5469          */
5470         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5471                 ext4_unregister_li_request(sb);
5472         else {
5473                 ext4_group_t first_not_zeroed;
5474                 first_not_zeroed = ext4_has_uninit_itable(sb);
5475                 ext4_register_li_request(sb, first_not_zeroed);
5476         }
5477
5478         ext4_setup_system_zone(sb);
5479         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
5480                 err = ext4_commit_super(sb, 1);
5481                 if (err)
5482                         goto restore_opts;
5483         }
5484
5485 #ifdef CONFIG_QUOTA
5486         /* Release old quota file names */
5487         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5488                 kfree(old_opts.s_qf_names[i]);
5489         if (enable_quota) {
5490                 if (sb_any_quota_suspended(sb))
5491                         dquot_resume(sb, -1);
5492                 else if (ext4_has_feature_quota(sb)) {
5493                         err = ext4_enable_quotas(sb);
5494                         if (err)
5495                                 goto restore_opts;
5496                 }
5497         }
5498 #endif
5499
5500         *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME);
5501         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5502         kfree(orig_data);
5503         return 0;
5504
5505 restore_opts:
5506         sb->s_flags = old_sb_flags;
5507         sbi->s_mount_opt = old_opts.s_mount_opt;
5508         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5509         sbi->s_resuid = old_opts.s_resuid;
5510         sbi->s_resgid = old_opts.s_resgid;
5511         sbi->s_commit_interval = old_opts.s_commit_interval;
5512         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5513         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5514 #ifdef CONFIG_QUOTA
5515         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5516         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5517                 to_free[i] = get_qf_name(sb, sbi, i);
5518                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
5519         }
5520         synchronize_rcu();
5521         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5522                 kfree(to_free[i]);
5523 #endif
5524         kfree(orig_data);
5525         return err;
5526 }
5527
5528 #ifdef CONFIG_QUOTA
5529 static int ext4_statfs_project(struct super_block *sb,
5530                                kprojid_t projid, struct kstatfs *buf)
5531 {
5532         struct kqid qid;
5533         struct dquot *dquot;
5534         u64 limit;
5535         u64 curblock;
5536
5537         qid = make_kqid_projid(projid);
5538         dquot = dqget(sb, qid);
5539         if (IS_ERR(dquot))
5540                 return PTR_ERR(dquot);
5541         spin_lock(&dquot->dq_dqb_lock);
5542
5543         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5544                  dquot->dq_dqb.dqb_bsoftlimit :
5545                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5546         if (limit && buf->f_blocks > limit) {
5547                 curblock = (dquot->dq_dqb.dqb_curspace +
5548                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
5549                 buf->f_blocks = limit;
5550                 buf->f_bfree = buf->f_bavail =
5551                         (buf->f_blocks > curblock) ?
5552                          (buf->f_blocks - curblock) : 0;
5553         }
5554
5555         limit = dquot->dq_dqb.dqb_isoftlimit ?
5556                 dquot->dq_dqb.dqb_isoftlimit :
5557                 dquot->dq_dqb.dqb_ihardlimit;
5558         if (limit && buf->f_files > limit) {
5559                 buf->f_files = limit;
5560                 buf->f_ffree =
5561                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5562                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5563         }
5564
5565         spin_unlock(&dquot->dq_dqb_lock);
5566         dqput(dquot);
5567         return 0;
5568 }
5569 #endif
5570
5571 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5572 {
5573         struct super_block *sb = dentry->d_sb;
5574         struct ext4_sb_info *sbi = EXT4_SB(sb);
5575         struct ext4_super_block *es = sbi->s_es;
5576         ext4_fsblk_t overhead = 0, resv_blocks;
5577         u64 fsid;
5578         s64 bfree;
5579         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5580
5581         if (!test_opt(sb, MINIX_DF))
5582                 overhead = sbi->s_overhead;
5583
5584         buf->f_type = EXT4_SUPER_MAGIC;
5585         buf->f_bsize = sb->s_blocksize;
5586         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5587         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5588                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5589         /* prevent underflow in case that few free space is available */
5590         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5591         buf->f_bavail = buf->f_bfree -
5592                         (ext4_r_blocks_count(es) + resv_blocks);
5593         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5594                 buf->f_bavail = 0;
5595         buf->f_files = le32_to_cpu(es->s_inodes_count);
5596         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5597         buf->f_namelen = EXT4_NAME_LEN;
5598         fsid = le64_to_cpup((void *)es->s_uuid) ^
5599                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5600         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5601         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5602
5603 #ifdef CONFIG_QUOTA
5604         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5605             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5606                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5607 #endif
5608         return 0;
5609 }
5610
5611
5612 #ifdef CONFIG_QUOTA
5613
5614 /*
5615  * Helper functions so that transaction is started before we acquire dqio_sem
5616  * to keep correct lock ordering of transaction > dqio_sem
5617  */
5618 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5619 {
5620         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5621 }
5622
5623 static int ext4_write_dquot(struct dquot *dquot)
5624 {
5625         int ret, err;
5626         handle_t *handle;
5627         struct inode *inode;
5628
5629         inode = dquot_to_inode(dquot);
5630         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5631                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5632         if (IS_ERR(handle))
5633                 return PTR_ERR(handle);
5634         ret = dquot_commit(dquot);
5635         err = ext4_journal_stop(handle);
5636         if (!ret)
5637                 ret = err;
5638         return ret;
5639 }
5640
5641 static int ext4_acquire_dquot(struct dquot *dquot)
5642 {
5643         int ret, err;
5644         handle_t *handle;
5645
5646         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5647                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5648         if (IS_ERR(handle))
5649                 return PTR_ERR(handle);
5650         ret = dquot_acquire(dquot);
5651         err = ext4_journal_stop(handle);
5652         if (!ret)
5653                 ret = err;
5654         return ret;
5655 }
5656
5657 static int ext4_release_dquot(struct dquot *dquot)
5658 {
5659         int ret, err;
5660         handle_t *handle;
5661
5662         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5663                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5664         if (IS_ERR(handle)) {
5665                 /* Release dquot anyway to avoid endless cycle in dqput() */
5666                 dquot_release(dquot);
5667                 return PTR_ERR(handle);
5668         }
5669         ret = dquot_release(dquot);
5670         err = ext4_journal_stop(handle);
5671         if (!ret)
5672                 ret = err;
5673         return ret;
5674 }
5675
5676 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5677 {
5678         struct super_block *sb = dquot->dq_sb;
5679         struct ext4_sb_info *sbi = EXT4_SB(sb);
5680
5681         /* Are we journaling quotas? */
5682         if (ext4_has_feature_quota(sb) ||
5683             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5684                 dquot_mark_dquot_dirty(dquot);
5685                 return ext4_write_dquot(dquot);
5686         } else {
5687                 return dquot_mark_dquot_dirty(dquot);
5688         }
5689 }
5690
5691 static int ext4_write_info(struct super_block *sb, int type)
5692 {
5693         int ret, err;
5694         handle_t *handle;
5695
5696         /* Data block + inode block */
5697         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5698         if (IS_ERR(handle))
5699                 return PTR_ERR(handle);
5700         ret = dquot_commit_info(sb, type);
5701         err = ext4_journal_stop(handle);
5702         if (!ret)
5703                 ret = err;
5704         return ret;
5705 }
5706
5707 /*
5708  * Turn on quotas during mount time - we need to find
5709  * the quota file and such...
5710  */
5711 static int ext4_quota_on_mount(struct super_block *sb, int type)
5712 {
5713         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
5714                                         EXT4_SB(sb)->s_jquota_fmt, type);
5715 }
5716
5717 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5718 {
5719         struct ext4_inode_info *ei = EXT4_I(inode);
5720
5721         /* The first argument of lockdep_set_subclass has to be
5722          * *exactly* the same as the argument to init_rwsem() --- in
5723          * this case, in init_once() --- or lockdep gets unhappy
5724          * because the name of the lock is set using the
5725          * stringification of the argument to init_rwsem().
5726          */
5727         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5728         lockdep_set_subclass(&ei->i_data_sem, subclass);
5729 }
5730
5731 /*
5732  * Standard function to be called on quota_on
5733  */
5734 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5735                          const struct path *path)
5736 {
5737         int err;
5738
5739         if (!test_opt(sb, QUOTA))
5740                 return -EINVAL;
5741
5742         /* Quotafile not on the same filesystem? */
5743         if (path->dentry->d_sb != sb)
5744                 return -EXDEV;
5745         /* Journaling quota? */
5746         if (EXT4_SB(sb)->s_qf_names[type]) {
5747                 /* Quotafile not in fs root? */
5748                 if (path->dentry->d_parent != sb->s_root)
5749                         ext4_msg(sb, KERN_WARNING,
5750                                 "Quota file not on filesystem root. "
5751                                 "Journaled quota will not work");
5752                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
5753         } else {
5754                 /*
5755                  * Clear the flag just in case mount options changed since
5756                  * last time.
5757                  */
5758                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
5759         }
5760
5761         /*
5762          * When we journal data on quota file, we have to flush journal to see
5763          * all updates to the file when we bypass pagecache...
5764          */
5765         if (EXT4_SB(sb)->s_journal &&
5766             ext4_should_journal_data(d_inode(path->dentry))) {
5767                 /*
5768                  * We don't need to lock updates but journal_flush() could
5769                  * otherwise be livelocked...
5770                  */
5771                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5772                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5773                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5774                 if (err)
5775                         return err;
5776         }
5777
5778         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5779         err = dquot_quota_on(sb, type, format_id, path);
5780         if (err) {
5781                 lockdep_set_quota_inode(path->dentry->d_inode,
5782                                              I_DATA_SEM_NORMAL);
5783         } else {
5784                 struct inode *inode = d_inode(path->dentry);
5785                 handle_t *handle;
5786
5787                 /*
5788                  * Set inode flags to prevent userspace from messing with quota
5789                  * files. If this fails, we return success anyway since quotas
5790                  * are already enabled and this is not a hard failure.
5791                  */
5792                 inode_lock(inode);
5793                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5794                 if (IS_ERR(handle))
5795                         goto unlock_inode;
5796                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
5797                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
5798                                 S_NOATIME | S_IMMUTABLE);
5799                 ext4_mark_inode_dirty(handle, inode);
5800                 ext4_journal_stop(handle);
5801         unlock_inode:
5802                 inode_unlock(inode);
5803         }
5804         return err;
5805 }
5806
5807 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5808                              unsigned int flags)
5809 {
5810         int err;
5811         struct inode *qf_inode;
5812         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5813                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5814                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5815                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5816         };
5817
5818         BUG_ON(!ext4_has_feature_quota(sb));
5819
5820         if (!qf_inums[type])
5821                 return -EPERM;
5822
5823         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5824         if (IS_ERR(qf_inode)) {
5825                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5826                 return PTR_ERR(qf_inode);
5827         }
5828
5829         /* Don't account quota for quota files to avoid recursion */
5830         qf_inode->i_flags |= S_NOQUOTA;
5831         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5832         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
5833         if (err)
5834                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5835         iput(qf_inode);
5836
5837         return err;
5838 }
5839
5840 /* Enable usage tracking for all quota types. */
5841 static int ext4_enable_quotas(struct super_block *sb)
5842 {
5843         int type, err = 0;
5844         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5845                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5846                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5847                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5848         };
5849         bool quota_mopt[EXT4_MAXQUOTAS] = {
5850                 test_opt(sb, USRQUOTA),
5851                 test_opt(sb, GRPQUOTA),
5852                 test_opt(sb, PRJQUOTA),
5853         };
5854
5855         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
5856         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5857                 if (qf_inums[type]) {
5858                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5859                                 DQUOT_USAGE_ENABLED |
5860                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5861                         if (err) {
5862                                 ext4_warning(sb,
5863                                         "Failed to enable quota tracking "
5864                                         "(type=%d, err=%d). Please run "
5865                                         "e2fsck to fix.", type, err);
5866                                 for (type--; type >= 0; type--)
5867                                         dquot_quota_off(sb, type);
5868
5869                                 return err;
5870                         }
5871                 }
5872         }
5873         return 0;
5874 }
5875
5876 static int ext4_quota_off(struct super_block *sb, int type)
5877 {
5878         struct inode *inode = sb_dqopt(sb)->files[type];
5879         handle_t *handle;
5880         int err;
5881
5882         /* Force all delayed allocation blocks to be allocated.
5883          * Caller already holds s_umount sem */
5884         if (test_opt(sb, DELALLOC))
5885                 sync_filesystem(sb);
5886
5887         if (!inode || !igrab(inode))
5888                 goto out;
5889
5890         err = dquot_quota_off(sb, type);
5891         if (err || ext4_has_feature_quota(sb))
5892                 goto out_put;
5893
5894         inode_lock(inode);
5895         /*
5896          * Update modification times of quota files when userspace can
5897          * start looking at them. If we fail, we return success anyway since
5898          * this is not a hard failure and quotas are already disabled.
5899          */
5900         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5901         if (IS_ERR(handle))
5902                 goto out_unlock;
5903         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
5904         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
5905         inode->i_mtime = inode->i_ctime = current_time(inode);
5906         ext4_mark_inode_dirty(handle, inode);
5907         ext4_journal_stop(handle);
5908 out_unlock:
5909         inode_unlock(inode);
5910 out_put:
5911         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
5912         iput(inode);
5913         return err;
5914 out:
5915         return dquot_quota_off(sb, type);
5916 }
5917
5918 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5919  * acquiring the locks... As quota files are never truncated and quota code
5920  * itself serializes the operations (and no one else should touch the files)
5921  * we don't have to be afraid of races */
5922 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5923                                size_t len, loff_t off)
5924 {
5925         struct inode *inode = sb_dqopt(sb)->files[type];
5926         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5927         int offset = off & (sb->s_blocksize - 1);
5928         int tocopy;
5929         size_t toread;
5930         struct buffer_head *bh;
5931         loff_t i_size = i_size_read(inode);
5932
5933         if (off > i_size)
5934                 return 0;
5935         if (off+len > i_size)
5936                 len = i_size-off;
5937         toread = len;
5938         while (toread > 0) {
5939                 tocopy = sb->s_blocksize - offset < toread ?
5940                                 sb->s_blocksize - offset : toread;
5941                 bh = ext4_bread(NULL, inode, blk, 0);
5942                 if (IS_ERR(bh))
5943                         return PTR_ERR(bh);
5944                 if (!bh)        /* A hole? */
5945                         memset(data, 0, tocopy);
5946                 else
5947                         memcpy(data, bh->b_data+offset, tocopy);
5948                 brelse(bh);
5949                 offset = 0;
5950                 toread -= tocopy;
5951                 data += tocopy;
5952                 blk++;
5953         }
5954         return len;
5955 }
5956
5957 /* Write to quotafile (we know the transaction is already started and has
5958  * enough credits) */
5959 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5960                                 const char *data, size_t len, loff_t off)
5961 {
5962         struct inode *inode = sb_dqopt(sb)->files[type];
5963         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5964         int err, offset = off & (sb->s_blocksize - 1);
5965         int retries = 0;
5966         struct buffer_head *bh;
5967         handle_t *handle = journal_current_handle();
5968
5969         if (EXT4_SB(sb)->s_journal && !handle) {
5970                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5971                         " cancelled because transaction is not started",
5972                         (unsigned long long)off, (unsigned long long)len);
5973                 return -EIO;
5974         }
5975         /*
5976          * Since we account only one data block in transaction credits,
5977          * then it is impossible to cross a block boundary.
5978          */
5979         if (sb->s_blocksize - offset < len) {
5980                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5981                         " cancelled because not block aligned",
5982                         (unsigned long long)off, (unsigned long long)len);
5983                 return -EIO;
5984         }
5985
5986         do {
5987                 bh = ext4_bread(handle, inode, blk,
5988                                 EXT4_GET_BLOCKS_CREATE |
5989                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5990         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5991                  ext4_should_retry_alloc(inode->i_sb, &retries));
5992         if (IS_ERR(bh))
5993                 return PTR_ERR(bh);
5994         if (!bh)
5995                 goto out;
5996         BUFFER_TRACE(bh, "get write access");
5997         err = ext4_journal_get_write_access(handle, bh);
5998         if (err) {
5999                 brelse(bh);
6000                 return err;
6001         }
6002         lock_buffer(bh);
6003         memcpy(bh->b_data+offset, data, len);
6004         flush_dcache_page(bh->b_page);
6005         unlock_buffer(bh);
6006         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6007         brelse(bh);
6008 out:
6009         if (inode->i_size < off + len) {
6010                 i_size_write(inode, off + len);
6011                 EXT4_I(inode)->i_disksize = inode->i_size;
6012                 ext4_mark_inode_dirty(handle, inode);
6013         }
6014         return len;
6015 }
6016 #endif
6017
6018 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6019                        const char *dev_name, void *data)
6020 {
6021         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6022 }
6023
6024 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6025 static inline void register_as_ext2(void)
6026 {
6027         int err = register_filesystem(&ext2_fs_type);
6028         if (err)
6029                 printk(KERN_WARNING
6030                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6031 }
6032
6033 static inline void unregister_as_ext2(void)
6034 {
6035         unregister_filesystem(&ext2_fs_type);
6036 }
6037
6038 static inline int ext2_feature_set_ok(struct super_block *sb)
6039 {
6040         if (ext4_has_unknown_ext2_incompat_features(sb))
6041                 return 0;
6042         if (sb_rdonly(sb))
6043                 return 1;
6044         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6045                 return 0;
6046         return 1;
6047 }
6048 #else
6049 static inline void register_as_ext2(void) { }
6050 static inline void unregister_as_ext2(void) { }
6051 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6052 #endif
6053
6054 static inline void register_as_ext3(void)
6055 {
6056         int err = register_filesystem(&ext3_fs_type);
6057         if (err)
6058                 printk(KERN_WARNING
6059                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6060 }
6061
6062 static inline void unregister_as_ext3(void)
6063 {
6064         unregister_filesystem(&ext3_fs_type);
6065 }
6066
6067 static inline int ext3_feature_set_ok(struct super_block *sb)
6068 {
6069         if (ext4_has_unknown_ext3_incompat_features(sb))
6070                 return 0;
6071         if (!ext4_has_feature_journal(sb))
6072                 return 0;
6073         if (sb_rdonly(sb))
6074                 return 1;
6075         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6076                 return 0;
6077         return 1;
6078 }
6079
6080 static struct file_system_type ext4_fs_type = {
6081         .owner          = THIS_MODULE,
6082         .name           = "ext4",
6083         .mount          = ext4_mount,
6084         .kill_sb        = kill_block_super,
6085         .fs_flags       = FS_REQUIRES_DEV,
6086 };
6087 MODULE_ALIAS_FS("ext4");
6088
6089 /* Shared across all ext4 file systems */
6090 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6091
6092 static int __init ext4_init_fs(void)
6093 {
6094         int i, err;
6095
6096         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6097         ext4_li_info = NULL;
6098         mutex_init(&ext4_li_mtx);
6099
6100         /* Build-time check for flags consistency */
6101         ext4_check_flag_values();
6102
6103         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6104                 init_waitqueue_head(&ext4__ioend_wq[i]);
6105
6106         err = ext4_init_es();
6107         if (err)
6108                 return err;
6109
6110         err = ext4_init_pending();
6111         if (err)
6112                 goto out7;
6113
6114         err = ext4_init_post_read_processing();
6115         if (err)
6116                 goto out6;
6117
6118         err = ext4_init_pageio();
6119         if (err)
6120                 goto out5;
6121
6122         err = ext4_init_system_zone();
6123         if (err)
6124                 goto out4;
6125
6126         err = ext4_init_sysfs();
6127         if (err)
6128                 goto out3;
6129
6130         err = ext4_init_mballoc();
6131         if (err)
6132                 goto out2;
6133         err = init_inodecache();
6134         if (err)
6135                 goto out1;
6136         register_as_ext3();
6137         register_as_ext2();
6138         err = register_filesystem(&ext4_fs_type);
6139         if (err)
6140                 goto out;
6141
6142         return 0;
6143 out:
6144         unregister_as_ext2();
6145         unregister_as_ext3();
6146         destroy_inodecache();
6147 out1:
6148         ext4_exit_mballoc();
6149 out2:
6150         ext4_exit_sysfs();
6151 out3:
6152         ext4_exit_system_zone();
6153 out4:
6154         ext4_exit_pageio();
6155 out5:
6156         ext4_exit_post_read_processing();
6157 out6:
6158         ext4_exit_pending();
6159 out7:
6160         ext4_exit_es();
6161
6162         return err;
6163 }
6164
6165 static void __exit ext4_exit_fs(void)
6166 {
6167         ext4_destroy_lazyinit_thread();
6168         unregister_as_ext2();
6169         unregister_as_ext3();
6170         unregister_filesystem(&ext4_fs_type);
6171         destroy_inodecache();
6172         ext4_exit_mballoc();
6173         ext4_exit_sysfs();
6174         ext4_exit_system_zone();
6175         ext4_exit_pageio();
6176         ext4_exit_post_read_processing();
6177         ext4_exit_es();
6178         ext4_exit_pending();
6179 }
6180
6181 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6182 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6183 MODULE_LICENSE("GPL");
6184 MODULE_SOFTDEP("pre: crc32c");
6185 module_init(ext4_init_fs)
6186 module_exit(ext4_exit_fs)