b4253fb7bab6b7e094b24b0f4c7c616ebf9b3399
[linux-2.6.git] / fs / ext4 / super.c
1 /*
2  *  linux/fs/ext4/super.c
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/fs/minix/inode.c
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  *
15  *  Big-endian to little-endian byte-swapping/bitmaps by
16  *        David S. Miller (davem@caip.rutgers.edu), 1995
17  */
18
19 #include <linux/module.h>
20 #include <linux/string.h>
21 #include <linux/fs.h>
22 #include <linux/time.h>
23 #include <linux/vmalloc.h>
24 #include <linux/jbd2.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/parser.h>
29 #include <linux/smp_lock.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/proc_fs.h>
39 #include <linux/ctype.h>
40 #include <linux/log2.h>
41 #include <linux/crc16.h>
42 #include <asm/uaccess.h>
43
44 #include "ext4.h"
45 #include "ext4_jbd2.h"
46 #include "xattr.h"
47 #include "acl.h"
48 #include "mballoc.h"
49
50 #define CREATE_TRACE_POINTS
51 #include <trace/events/ext4.h>
52
53 struct proc_dir_entry *ext4_proc_root;
54 static struct kset *ext4_kset;
55
56 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
57                              unsigned long journal_devnum);
58 static int ext4_commit_super(struct super_block *sb, int sync);
59 static void ext4_mark_recovery_complete(struct super_block *sb,
60                                         struct ext4_super_block *es);
61 static void ext4_clear_journal_err(struct super_block *sb,
62                                    struct ext4_super_block *es);
63 static int ext4_sync_fs(struct super_block *sb, int wait);
64 static const char *ext4_decode_error(struct super_block *sb, int errno,
65                                      char nbuf[16]);
66 static int ext4_remount(struct super_block *sb, int *flags, char *data);
67 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
68 static int ext4_unfreeze(struct super_block *sb);
69 static void ext4_write_super(struct super_block *sb);
70 static int ext4_freeze(struct super_block *sb);
71
72
73 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
74                                struct ext4_group_desc *bg)
75 {
76         return le32_to_cpu(bg->bg_block_bitmap_lo) |
77                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
78                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
79 }
80
81 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
82                                struct ext4_group_desc *bg)
83 {
84         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
85                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
86                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
87 }
88
89 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
90                               struct ext4_group_desc *bg)
91 {
92         return le32_to_cpu(bg->bg_inode_table_lo) |
93                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
94                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
95 }
96
97 __u32 ext4_free_blks_count(struct super_block *sb,
98                               struct ext4_group_desc *bg)
99 {
100         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
101                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
102                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
103 }
104
105 __u32 ext4_free_inodes_count(struct super_block *sb,
106                               struct ext4_group_desc *bg)
107 {
108         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
109                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
110                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
111 }
112
113 __u32 ext4_used_dirs_count(struct super_block *sb,
114                               struct ext4_group_desc *bg)
115 {
116         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
117                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
118                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
119 }
120
121 __u32 ext4_itable_unused_count(struct super_block *sb,
122                               struct ext4_group_desc *bg)
123 {
124         return le16_to_cpu(bg->bg_itable_unused_lo) |
125                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
126                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
127 }
128
129 void ext4_block_bitmap_set(struct super_block *sb,
130                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
131 {
132         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
133         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
134                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
135 }
136
137 void ext4_inode_bitmap_set(struct super_block *sb,
138                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
139 {
140         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
141         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
142                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
143 }
144
145 void ext4_inode_table_set(struct super_block *sb,
146                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
147 {
148         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
149         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
150                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
151 }
152
153 void ext4_free_blks_set(struct super_block *sb,
154                           struct ext4_group_desc *bg, __u32 count)
155 {
156         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
157         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
158                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
159 }
160
161 void ext4_free_inodes_set(struct super_block *sb,
162                           struct ext4_group_desc *bg, __u32 count)
163 {
164         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
165         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
166                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
167 }
168
169 void ext4_used_dirs_set(struct super_block *sb,
170                           struct ext4_group_desc *bg, __u32 count)
171 {
172         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
173         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
174                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
175 }
176
177 void ext4_itable_unused_set(struct super_block *sb,
178                           struct ext4_group_desc *bg, __u32 count)
179 {
180         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
181         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
182                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
183 }
184
185
186 /* Just increment the non-pointer handle value */
187 static handle_t *ext4_get_nojournal(void)
188 {
189         handle_t *handle = current->journal_info;
190         unsigned long ref_cnt = (unsigned long)handle;
191
192         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
193
194         ref_cnt++;
195         handle = (handle_t *)ref_cnt;
196
197         current->journal_info = handle;
198         return handle;
199 }
200
201
202 /* Decrement the non-pointer handle value */
203 static void ext4_put_nojournal(handle_t *handle)
204 {
205         unsigned long ref_cnt = (unsigned long)handle;
206
207         BUG_ON(ref_cnt == 0);
208
209         ref_cnt--;
210         handle = (handle_t *)ref_cnt;
211
212         current->journal_info = handle;
213 }
214
215 /*
216  * Wrappers for jbd2_journal_start/end.
217  *
218  * The only special thing we need to do here is to make sure that all
219  * journal_end calls result in the superblock being marked dirty, so
220  * that sync() will call the filesystem's write_super callback if
221  * appropriate.
222  */
223 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
224 {
225         journal_t *journal;
226
227         if (sb->s_flags & MS_RDONLY)
228                 return ERR_PTR(-EROFS);
229
230         /* Special case here: if the journal has aborted behind our
231          * backs (eg. EIO in the commit thread), then we still need to
232          * take the FS itself readonly cleanly. */
233         journal = EXT4_SB(sb)->s_journal;
234         if (journal) {
235                 if (is_journal_aborted(journal)) {
236                         ext4_abort(sb, __func__, "Detected aborted journal");
237                         return ERR_PTR(-EROFS);
238                 }
239                 return jbd2_journal_start(journal, nblocks);
240         }
241         return ext4_get_nojournal();
242 }
243
244 /*
245  * The only special thing we need to do here is to make sure that all
246  * jbd2_journal_stop calls result in the superblock being marked dirty, so
247  * that sync() will call the filesystem's write_super callback if
248  * appropriate.
249  */
250 int __ext4_journal_stop(const char *where, handle_t *handle)
251 {
252         struct super_block *sb;
253         int err;
254         int rc;
255
256         if (!ext4_handle_valid(handle)) {
257                 ext4_put_nojournal(handle);
258                 return 0;
259         }
260         sb = handle->h_transaction->t_journal->j_private;
261         err = handle->h_err;
262         rc = jbd2_journal_stop(handle);
263
264         if (!err)
265                 err = rc;
266         if (err)
267                 __ext4_std_error(sb, where, err);
268         return err;
269 }
270
271 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
272                 struct buffer_head *bh, handle_t *handle, int err)
273 {
274         char nbuf[16];
275         const char *errstr = ext4_decode_error(NULL, err, nbuf);
276
277         BUG_ON(!ext4_handle_valid(handle));
278
279         if (bh)
280                 BUFFER_TRACE(bh, "abort");
281
282         if (!handle->h_err)
283                 handle->h_err = err;
284
285         if (is_handle_aborted(handle))
286                 return;
287
288         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
289                caller, errstr, err_fn);
290
291         jbd2_journal_abort_handle(handle);
292 }
293
294 /* Deal with the reporting of failure conditions on a filesystem such as
295  * inconsistencies detected or read IO failures.
296  *
297  * On ext2, we can store the error state of the filesystem in the
298  * superblock.  That is not possible on ext4, because we may have other
299  * write ordering constraints on the superblock which prevent us from
300  * writing it out straight away; and given that the journal is about to
301  * be aborted, we can't rely on the current, or future, transactions to
302  * write out the superblock safely.
303  *
304  * We'll just use the jbd2_journal_abort() error code to record an error in
305  * the journal instead.  On recovery, the journal will compain about
306  * that error until we've noted it down and cleared it.
307  */
308
309 static void ext4_handle_error(struct super_block *sb)
310 {
311         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
312
313         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
314         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
315
316         if (sb->s_flags & MS_RDONLY)
317                 return;
318
319         if (!test_opt(sb, ERRORS_CONT)) {
320                 journal_t *journal = EXT4_SB(sb)->s_journal;
321
322                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
323                 if (journal)
324                         jbd2_journal_abort(journal, -EIO);
325         }
326         if (test_opt(sb, ERRORS_RO)) {
327                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
328                 sb->s_flags |= MS_RDONLY;
329         }
330         ext4_commit_super(sb, 1);
331         if (test_opt(sb, ERRORS_PANIC))
332                 panic("EXT4-fs (device %s): panic forced after error\n",
333                         sb->s_id);
334 }
335
336 void ext4_error(struct super_block *sb, const char *function,
337                 const char *fmt, ...)
338 {
339         va_list args;
340
341         va_start(args, fmt);
342         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
343         vprintk(fmt, args);
344         printk("\n");
345         va_end(args);
346
347         ext4_handle_error(sb);
348 }
349
350 static const char *ext4_decode_error(struct super_block *sb, int errno,
351                                      char nbuf[16])
352 {
353         char *errstr = NULL;
354
355         switch (errno) {
356         case -EIO:
357                 errstr = "IO failure";
358                 break;
359         case -ENOMEM:
360                 errstr = "Out of memory";
361                 break;
362         case -EROFS:
363                 if (!sb || (EXT4_SB(sb)->s_journal &&
364                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
365                         errstr = "Journal has aborted";
366                 else
367                         errstr = "Readonly filesystem";
368                 break;
369         default:
370                 /* If the caller passed in an extra buffer for unknown
371                  * errors, textualise them now.  Else we just return
372                  * NULL. */
373                 if (nbuf) {
374                         /* Check for truncated error codes... */
375                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
376                                 errstr = nbuf;
377                 }
378                 break;
379         }
380
381         return errstr;
382 }
383
384 /* __ext4_std_error decodes expected errors from journaling functions
385  * automatically and invokes the appropriate error response.  */
386
387 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
388 {
389         char nbuf[16];
390         const char *errstr;
391
392         /* Special case: if the error is EROFS, and we're not already
393          * inside a transaction, then there's really no point in logging
394          * an error. */
395         if (errno == -EROFS && journal_current_handle() == NULL &&
396             (sb->s_flags & MS_RDONLY))
397                 return;
398
399         errstr = ext4_decode_error(sb, errno, nbuf);
400         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
401                sb->s_id, function, errstr);
402
403         ext4_handle_error(sb);
404 }
405
406 /*
407  * ext4_abort is a much stronger failure handler than ext4_error.  The
408  * abort function may be used to deal with unrecoverable failures such
409  * as journal IO errors or ENOMEM at a critical moment in log management.
410  *
411  * We unconditionally force the filesystem into an ABORT|READONLY state,
412  * unless the error response on the fs has been set to panic in which
413  * case we take the easy way out and panic immediately.
414  */
415
416 void ext4_abort(struct super_block *sb, const char *function,
417                 const char *fmt, ...)
418 {
419         va_list args;
420
421         va_start(args, fmt);
422         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
423         vprintk(fmt, args);
424         printk("\n");
425         va_end(args);
426
427         if (test_opt(sb, ERRORS_PANIC))
428                 panic("EXT4-fs panic from previous error\n");
429
430         if (sb->s_flags & MS_RDONLY)
431                 return;
432
433         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
434         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
435         sb->s_flags |= MS_RDONLY;
436         EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
437         if (EXT4_SB(sb)->s_journal)
438                 jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
439 }
440
441 void ext4_msg (struct super_block * sb, const char *prefix,
442                    const char *fmt, ...)
443 {
444         va_list args;
445
446         va_start(args, fmt);
447         printk("%sEXT4-fs (%s): ", prefix, sb->s_id);
448         vprintk(fmt, args);
449         printk("\n");
450         va_end(args);
451 }
452
453 void ext4_warning(struct super_block *sb, const char *function,
454                   const char *fmt, ...)
455 {
456         va_list args;
457
458         va_start(args, fmt);
459         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
460                sb->s_id, function);
461         vprintk(fmt, args);
462         printk("\n");
463         va_end(args);
464 }
465
466 void ext4_grp_locked_error(struct super_block *sb, ext4_group_t grp,
467                            const char *function, const char *fmt, ...)
468 __releases(bitlock)
469 __acquires(bitlock)
470 {
471         va_list args;
472         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
473
474         va_start(args, fmt);
475         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
476         vprintk(fmt, args);
477         printk("\n");
478         va_end(args);
479
480         if (test_opt(sb, ERRORS_CONT)) {
481                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
482                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
483                 ext4_commit_super(sb, 0);
484                 return;
485         }
486         ext4_unlock_group(sb, grp);
487         ext4_handle_error(sb);
488         /*
489          * We only get here in the ERRORS_RO case; relocking the group
490          * may be dangerous, but nothing bad will happen since the
491          * filesystem will have already been marked read/only and the
492          * journal has been aborted.  We return 1 as a hint to callers
493          * who might what to use the return value from
494          * ext4_grp_locked_error() to distinguish beween the
495          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
496          * aggressively from the ext4 function in question, with a
497          * more appropriate error code.
498          */
499         ext4_lock_group(sb, grp);
500         return;
501 }
502
503 void ext4_update_dynamic_rev(struct super_block *sb)
504 {
505         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
506
507         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
508                 return;
509
510         ext4_warning(sb, __func__,
511                      "updating to rev %d because of new feature flag, "
512                      "running e2fsck is recommended",
513                      EXT4_DYNAMIC_REV);
514
515         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
516         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
517         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
518         /* leave es->s_feature_*compat flags alone */
519         /* es->s_uuid will be set by e2fsck if empty */
520
521         /*
522          * The rest of the superblock fields should be zero, and if not it
523          * means they are likely already in use, so leave them alone.  We
524          * can leave it up to e2fsck to clean up any inconsistencies there.
525          */
526 }
527
528 /*
529  * Open the external journal device
530  */
531 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
532 {
533         struct block_device *bdev;
534         char b[BDEVNAME_SIZE];
535
536         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
537         if (IS_ERR(bdev))
538                 goto fail;
539         return bdev;
540
541 fail:
542         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
543                         __bdevname(dev, b), PTR_ERR(bdev));
544         return NULL;
545 }
546
547 /*
548  * Release the journal device
549  */
550 static int ext4_blkdev_put(struct block_device *bdev)
551 {
552         bd_release(bdev);
553         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
554 }
555
556 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
557 {
558         struct block_device *bdev;
559         int ret = -ENODEV;
560
561         bdev = sbi->journal_bdev;
562         if (bdev) {
563                 ret = ext4_blkdev_put(bdev);
564                 sbi->journal_bdev = NULL;
565         }
566         return ret;
567 }
568
569 static inline struct inode *orphan_list_entry(struct list_head *l)
570 {
571         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
572 }
573
574 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
575 {
576         struct list_head *l;
577
578         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
579                  le32_to_cpu(sbi->s_es->s_last_orphan));
580
581         printk(KERN_ERR "sb_info orphan list:\n");
582         list_for_each(l, &sbi->s_orphan) {
583                 struct inode *inode = orphan_list_entry(l);
584                 printk(KERN_ERR "  "
585                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
586                        inode->i_sb->s_id, inode->i_ino, inode,
587                        inode->i_mode, inode->i_nlink,
588                        NEXT_ORPHAN(inode));
589         }
590 }
591
592 static void ext4_put_super(struct super_block *sb)
593 {
594         struct ext4_sb_info *sbi = EXT4_SB(sb);
595         struct ext4_super_block *es = sbi->s_es;
596         int i, err;
597
598         flush_workqueue(sbi->dio_unwritten_wq);
599         destroy_workqueue(sbi->dio_unwritten_wq);
600
601         lock_super(sb);
602         lock_kernel();
603         if (sb->s_dirt)
604                 ext4_commit_super(sb, 1);
605
606         if (sbi->s_journal) {
607                 err = jbd2_journal_destroy(sbi->s_journal);
608                 sbi->s_journal = NULL;
609                 if (err < 0)
610                         ext4_abort(sb, __func__,
611                                    "Couldn't clean up the journal");
612         }
613
614         ext4_release_system_zone(sb);
615         ext4_mb_release(sb);
616         ext4_ext_release(sb);
617         ext4_xattr_put_super(sb);
618
619         if (!(sb->s_flags & MS_RDONLY)) {
620                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
621                 es->s_state = cpu_to_le16(sbi->s_mount_state);
622                 ext4_commit_super(sb, 1);
623         }
624         if (sbi->s_proc) {
625                 remove_proc_entry(sb->s_id, ext4_proc_root);
626         }
627         kobject_del(&sbi->s_kobj);
628
629         for (i = 0; i < sbi->s_gdb_count; i++)
630                 brelse(sbi->s_group_desc[i]);
631         kfree(sbi->s_group_desc);
632         if (is_vmalloc_addr(sbi->s_flex_groups))
633                 vfree(sbi->s_flex_groups);
634         else
635                 kfree(sbi->s_flex_groups);
636         percpu_counter_destroy(&sbi->s_freeblocks_counter);
637         percpu_counter_destroy(&sbi->s_freeinodes_counter);
638         percpu_counter_destroy(&sbi->s_dirs_counter);
639         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
640         brelse(sbi->s_sbh);
641 #ifdef CONFIG_QUOTA
642         for (i = 0; i < MAXQUOTAS; i++)
643                 kfree(sbi->s_qf_names[i]);
644 #endif
645
646         /* Debugging code just in case the in-memory inode orphan list
647          * isn't empty.  The on-disk one can be non-empty if we've
648          * detected an error and taken the fs readonly, but the
649          * in-memory list had better be clean by this point. */
650         if (!list_empty(&sbi->s_orphan))
651                 dump_orphan_list(sb, sbi);
652         J_ASSERT(list_empty(&sbi->s_orphan));
653
654         invalidate_bdev(sb->s_bdev);
655         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
656                 /*
657                  * Invalidate the journal device's buffers.  We don't want them
658                  * floating about in memory - the physical journal device may
659                  * hotswapped, and it breaks the `ro-after' testing code.
660                  */
661                 sync_blockdev(sbi->journal_bdev);
662                 invalidate_bdev(sbi->journal_bdev);
663                 ext4_blkdev_remove(sbi);
664         }
665         sb->s_fs_info = NULL;
666         /*
667          * Now that we are completely done shutting down the
668          * superblock, we need to actually destroy the kobject.
669          */
670         unlock_kernel();
671         unlock_super(sb);
672         kobject_put(&sbi->s_kobj);
673         wait_for_completion(&sbi->s_kobj_unregister);
674         kfree(sbi->s_blockgroup_lock);
675         kfree(sbi);
676 }
677
678 static struct kmem_cache *ext4_inode_cachep;
679
680 /*
681  * Called inside transaction, so use GFP_NOFS
682  */
683 static struct inode *ext4_alloc_inode(struct super_block *sb)
684 {
685         struct ext4_inode_info *ei;
686
687         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
688         if (!ei)
689                 return NULL;
690
691         ei->vfs_inode.i_version = 1;
692         ei->vfs_inode.i_data.writeback_index = 0;
693         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
694         INIT_LIST_HEAD(&ei->i_prealloc_list);
695         spin_lock_init(&ei->i_prealloc_lock);
696         /*
697          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
698          * therefore it can be null here.  Don't check it, just initialize
699          * jinode.
700          */
701         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
702         ei->i_reserved_data_blocks = 0;
703         ei->i_reserved_meta_blocks = 0;
704         ei->i_allocated_meta_blocks = 0;
705         ei->i_da_metadata_calc_len = 0;
706         ei->i_delalloc_reserved_flag = 0;
707         spin_lock_init(&(ei->i_block_reservation_lock));
708 #ifdef CONFIG_QUOTA
709         ei->i_reserved_quota = 0;
710 #endif
711         INIT_LIST_HEAD(&ei->i_aio_dio_complete_list);
712         ei->cur_aio_dio = NULL;
713         ei->i_sync_tid = 0;
714         ei->i_datasync_tid = 0;
715
716         return &ei->vfs_inode;
717 }
718
719 static void ext4_destroy_inode(struct inode *inode)
720 {
721         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
722                 ext4_msg(inode->i_sb, KERN_ERR,
723                          "Inode %lu (%p): orphan list check failed!",
724                          inode->i_ino, EXT4_I(inode));
725                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
726                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
727                                 true);
728                 dump_stack();
729         }
730         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
731 }
732
733 static void init_once(void *foo)
734 {
735         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
736
737         INIT_LIST_HEAD(&ei->i_orphan);
738 #ifdef CONFIG_EXT4_FS_XATTR
739         init_rwsem(&ei->xattr_sem);
740 #endif
741         init_rwsem(&ei->i_data_sem);
742         inode_init_once(&ei->vfs_inode);
743 }
744
745 static int init_inodecache(void)
746 {
747         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
748                                              sizeof(struct ext4_inode_info),
749                                              0, (SLAB_RECLAIM_ACCOUNT|
750                                                 SLAB_MEM_SPREAD),
751                                              init_once);
752         if (ext4_inode_cachep == NULL)
753                 return -ENOMEM;
754         return 0;
755 }
756
757 static void destroy_inodecache(void)
758 {
759         kmem_cache_destroy(ext4_inode_cachep);
760 }
761
762 static void ext4_clear_inode(struct inode *inode)
763 {
764         ext4_discard_preallocations(inode);
765         if (EXT4_JOURNAL(inode))
766                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
767                                        &EXT4_I(inode)->jinode);
768 }
769
770 static inline void ext4_show_quota_options(struct seq_file *seq,
771                                            struct super_block *sb)
772 {
773 #if defined(CONFIG_QUOTA)
774         struct ext4_sb_info *sbi = EXT4_SB(sb);
775
776         if (sbi->s_jquota_fmt) {
777                 char *fmtname = "";
778
779                 switch (sbi->s_jquota_fmt) {
780                 case QFMT_VFS_OLD:
781                         fmtname = "vfsold";
782                         break;
783                 case QFMT_VFS_V0:
784                         fmtname = "vfsv0";
785                         break;
786                 case QFMT_VFS_V1:
787                         fmtname = "vfsv1";
788                         break;
789                 }
790                 seq_printf(seq, ",jqfmt=%s", fmtname);
791         }
792
793         if (sbi->s_qf_names[USRQUOTA])
794                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
795
796         if (sbi->s_qf_names[GRPQUOTA])
797                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
798
799         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
800                 seq_puts(seq, ",usrquota");
801
802         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
803                 seq_puts(seq, ",grpquota");
804 #endif
805 }
806
807 /*
808  * Show an option if
809  *  - it's set to a non-default value OR
810  *  - if the per-sb default is different from the global default
811  */
812 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
813 {
814         int def_errors;
815         unsigned long def_mount_opts;
816         struct super_block *sb = vfs->mnt_sb;
817         struct ext4_sb_info *sbi = EXT4_SB(sb);
818         struct ext4_super_block *es = sbi->s_es;
819
820         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
821         def_errors     = le16_to_cpu(es->s_errors);
822
823         if (sbi->s_sb_block != 1)
824                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
825         if (test_opt(sb, MINIX_DF))
826                 seq_puts(seq, ",minixdf");
827         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
828                 seq_puts(seq, ",grpid");
829         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
830                 seq_puts(seq, ",nogrpid");
831         if (sbi->s_resuid != EXT4_DEF_RESUID ||
832             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
833                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
834         }
835         if (sbi->s_resgid != EXT4_DEF_RESGID ||
836             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
837                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
838         }
839         if (test_opt(sb, ERRORS_RO)) {
840                 if (def_errors == EXT4_ERRORS_PANIC ||
841                     def_errors == EXT4_ERRORS_CONTINUE) {
842                         seq_puts(seq, ",errors=remount-ro");
843                 }
844         }
845         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
846                 seq_puts(seq, ",errors=continue");
847         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
848                 seq_puts(seq, ",errors=panic");
849         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
850                 seq_puts(seq, ",nouid32");
851         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
852                 seq_puts(seq, ",debug");
853         if (test_opt(sb, OLDALLOC))
854                 seq_puts(seq, ",oldalloc");
855 #ifdef CONFIG_EXT4_FS_XATTR
856         if (test_opt(sb, XATTR_USER) &&
857                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
858                 seq_puts(seq, ",user_xattr");
859         if (!test_opt(sb, XATTR_USER) &&
860             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
861                 seq_puts(seq, ",nouser_xattr");
862         }
863 #endif
864 #ifdef CONFIG_EXT4_FS_POSIX_ACL
865         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
866                 seq_puts(seq, ",acl");
867         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
868                 seq_puts(seq, ",noacl");
869 #endif
870         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
871                 seq_printf(seq, ",commit=%u",
872                            (unsigned) (sbi->s_commit_interval / HZ));
873         }
874         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
875                 seq_printf(seq, ",min_batch_time=%u",
876                            (unsigned) sbi->s_min_batch_time);
877         }
878         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
879                 seq_printf(seq, ",max_batch_time=%u",
880                            (unsigned) sbi->s_min_batch_time);
881         }
882
883         /*
884          * We're changing the default of barrier mount option, so
885          * let's always display its mount state so it's clear what its
886          * status is.
887          */
888         seq_puts(seq, ",barrier=");
889         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
890         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
891                 seq_puts(seq, ",journal_async_commit");
892         if (test_opt(sb, NOBH))
893                 seq_puts(seq, ",nobh");
894         if (test_opt(sb, I_VERSION))
895                 seq_puts(seq, ",i_version");
896         if (!test_opt(sb, DELALLOC))
897                 seq_puts(seq, ",nodelalloc");
898
899
900         if (sbi->s_stripe)
901                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
902         /*
903          * journal mode get enabled in different ways
904          * So just print the value even if we didn't specify it
905          */
906         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
907                 seq_puts(seq, ",data=journal");
908         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
909                 seq_puts(seq, ",data=ordered");
910         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
911                 seq_puts(seq, ",data=writeback");
912
913         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
914                 seq_printf(seq, ",inode_readahead_blks=%u",
915                            sbi->s_inode_readahead_blks);
916
917         if (test_opt(sb, DATA_ERR_ABORT))
918                 seq_puts(seq, ",data_err=abort");
919
920         if (test_opt(sb, NO_AUTO_DA_ALLOC))
921                 seq_puts(seq, ",noauto_da_alloc");
922
923         if (test_opt(sb, DISCARD))
924                 seq_puts(seq, ",discard");
925
926         if (test_opt(sb, NOLOAD))
927                 seq_puts(seq, ",norecovery");
928
929         ext4_show_quota_options(seq, sb);
930
931         return 0;
932 }
933
934 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
935                                         u64 ino, u32 generation)
936 {
937         struct inode *inode;
938
939         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
940                 return ERR_PTR(-ESTALE);
941         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
942                 return ERR_PTR(-ESTALE);
943
944         /* iget isn't really right if the inode is currently unallocated!!
945          *
946          * ext4_read_inode will return a bad_inode if the inode had been
947          * deleted, so we should be safe.
948          *
949          * Currently we don't know the generation for parent directory, so
950          * a generation of 0 means "accept any"
951          */
952         inode = ext4_iget(sb, ino);
953         if (IS_ERR(inode))
954                 return ERR_CAST(inode);
955         if (generation && inode->i_generation != generation) {
956                 iput(inode);
957                 return ERR_PTR(-ESTALE);
958         }
959
960         return inode;
961 }
962
963 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
964                                         int fh_len, int fh_type)
965 {
966         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
967                                     ext4_nfs_get_inode);
968 }
969
970 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
971                                         int fh_len, int fh_type)
972 {
973         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
974                                     ext4_nfs_get_inode);
975 }
976
977 /*
978  * Try to release metadata pages (indirect blocks, directories) which are
979  * mapped via the block device.  Since these pages could have journal heads
980  * which would prevent try_to_free_buffers() from freeing them, we must use
981  * jbd2 layer's try_to_free_buffers() function to release them.
982  */
983 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
984                                  gfp_t wait)
985 {
986         journal_t *journal = EXT4_SB(sb)->s_journal;
987
988         WARN_ON(PageChecked(page));
989         if (!page_has_buffers(page))
990                 return 0;
991         if (journal)
992                 return jbd2_journal_try_to_free_buffers(journal, page,
993                                                         wait & ~__GFP_WAIT);
994         return try_to_free_buffers(page);
995 }
996
997 #ifdef CONFIG_QUOTA
998 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
999 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1000
1001 static int ext4_write_dquot(struct dquot *dquot);
1002 static int ext4_acquire_dquot(struct dquot *dquot);
1003 static int ext4_release_dquot(struct dquot *dquot);
1004 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1005 static int ext4_write_info(struct super_block *sb, int type);
1006 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1007                                 char *path, int remount);
1008 static int ext4_quota_on_mount(struct super_block *sb, int type);
1009 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1010                                size_t len, loff_t off);
1011 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1012                                 const char *data, size_t len, loff_t off);
1013
1014 static const struct dquot_operations ext4_quota_operations = {
1015         .initialize     = dquot_initialize,
1016         .drop           = dquot_drop,
1017 #ifdef CONFIG_QUOTA
1018         .get_reserved_space = ext4_get_reserved_space,
1019 #endif
1020         .write_dquot    = ext4_write_dquot,
1021         .acquire_dquot  = ext4_acquire_dquot,
1022         .release_dquot  = ext4_release_dquot,
1023         .mark_dirty     = ext4_mark_dquot_dirty,
1024         .write_info     = ext4_write_info,
1025         .alloc_dquot    = dquot_alloc,
1026         .destroy_dquot  = dquot_destroy,
1027 };
1028
1029 static const struct quotactl_ops ext4_qctl_operations = {
1030         .quota_on       = ext4_quota_on,
1031         .quota_off      = vfs_quota_off,
1032         .quota_sync     = vfs_quota_sync,
1033         .get_info       = vfs_get_dqinfo,
1034         .set_info       = vfs_set_dqinfo,
1035         .get_dqblk      = vfs_get_dqblk,
1036         .set_dqblk      = vfs_set_dqblk
1037 };
1038 #endif
1039
1040 static const struct super_operations ext4_sops = {
1041         .alloc_inode    = ext4_alloc_inode,
1042         .destroy_inode  = ext4_destroy_inode,
1043         .write_inode    = ext4_write_inode,
1044         .dirty_inode    = ext4_dirty_inode,
1045         .delete_inode   = ext4_delete_inode,
1046         .put_super      = ext4_put_super,
1047         .sync_fs        = ext4_sync_fs,
1048         .freeze_fs      = ext4_freeze,
1049         .unfreeze_fs    = ext4_unfreeze,
1050         .statfs         = ext4_statfs,
1051         .remount_fs     = ext4_remount,
1052         .clear_inode    = ext4_clear_inode,
1053         .show_options   = ext4_show_options,
1054 #ifdef CONFIG_QUOTA
1055         .quota_read     = ext4_quota_read,
1056         .quota_write    = ext4_quota_write,
1057 #endif
1058         .bdev_try_to_free_page = bdev_try_to_free_page,
1059 };
1060
1061 static const struct super_operations ext4_nojournal_sops = {
1062         .alloc_inode    = ext4_alloc_inode,
1063         .destroy_inode  = ext4_destroy_inode,
1064         .write_inode    = ext4_write_inode,
1065         .dirty_inode    = ext4_dirty_inode,
1066         .delete_inode   = ext4_delete_inode,
1067         .write_super    = ext4_write_super,
1068         .put_super      = ext4_put_super,
1069         .statfs         = ext4_statfs,
1070         .remount_fs     = ext4_remount,
1071         .clear_inode    = ext4_clear_inode,
1072         .show_options   = ext4_show_options,
1073 #ifdef CONFIG_QUOTA
1074         .quota_read     = ext4_quota_read,
1075         .quota_write    = ext4_quota_write,
1076 #endif
1077         .bdev_try_to_free_page = bdev_try_to_free_page,
1078 };
1079
1080 static const struct export_operations ext4_export_ops = {
1081         .fh_to_dentry = ext4_fh_to_dentry,
1082         .fh_to_parent = ext4_fh_to_parent,
1083         .get_parent = ext4_get_parent,
1084 };
1085
1086 enum {
1087         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1088         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1089         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1090         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1091         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1092         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1093         Opt_journal_update, Opt_journal_dev,
1094         Opt_journal_checksum, Opt_journal_async_commit,
1095         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1096         Opt_data_err_abort, Opt_data_err_ignore,
1097         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1098         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1099         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1100         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1101         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1102         Opt_block_validity, Opt_noblock_validity,
1103         Opt_inode_readahead_blks, Opt_journal_ioprio,
1104         Opt_discard, Opt_nodiscard,
1105 };
1106
1107 static const match_table_t tokens = {
1108         {Opt_bsd_df, "bsddf"},
1109         {Opt_minix_df, "minixdf"},
1110         {Opt_grpid, "grpid"},
1111         {Opt_grpid, "bsdgroups"},
1112         {Opt_nogrpid, "nogrpid"},
1113         {Opt_nogrpid, "sysvgroups"},
1114         {Opt_resgid, "resgid=%u"},
1115         {Opt_resuid, "resuid=%u"},
1116         {Opt_sb, "sb=%u"},
1117         {Opt_err_cont, "errors=continue"},
1118         {Opt_err_panic, "errors=panic"},
1119         {Opt_err_ro, "errors=remount-ro"},
1120         {Opt_nouid32, "nouid32"},
1121         {Opt_debug, "debug"},
1122         {Opt_oldalloc, "oldalloc"},
1123         {Opt_orlov, "orlov"},
1124         {Opt_user_xattr, "user_xattr"},
1125         {Opt_nouser_xattr, "nouser_xattr"},
1126         {Opt_acl, "acl"},
1127         {Opt_noacl, "noacl"},
1128         {Opt_noload, "noload"},
1129         {Opt_noload, "norecovery"},
1130         {Opt_nobh, "nobh"},
1131         {Opt_bh, "bh"},
1132         {Opt_commit, "commit=%u"},
1133         {Opt_min_batch_time, "min_batch_time=%u"},
1134         {Opt_max_batch_time, "max_batch_time=%u"},
1135         {Opt_journal_update, "journal=update"},
1136         {Opt_journal_dev, "journal_dev=%u"},
1137         {Opt_journal_checksum, "journal_checksum"},
1138         {Opt_journal_async_commit, "journal_async_commit"},
1139         {Opt_abort, "abort"},
1140         {Opt_data_journal, "data=journal"},
1141         {Opt_data_ordered, "data=ordered"},
1142         {Opt_data_writeback, "data=writeback"},
1143         {Opt_data_err_abort, "data_err=abort"},
1144         {Opt_data_err_ignore, "data_err=ignore"},
1145         {Opt_offusrjquota, "usrjquota="},
1146         {Opt_usrjquota, "usrjquota=%s"},
1147         {Opt_offgrpjquota, "grpjquota="},
1148         {Opt_grpjquota, "grpjquota=%s"},
1149         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1150         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1151         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1152         {Opt_grpquota, "grpquota"},
1153         {Opt_noquota, "noquota"},
1154         {Opt_quota, "quota"},
1155         {Opt_usrquota, "usrquota"},
1156         {Opt_barrier, "barrier=%u"},
1157         {Opt_barrier, "barrier"},
1158         {Opt_nobarrier, "nobarrier"},
1159         {Opt_i_version, "i_version"},
1160         {Opt_stripe, "stripe=%u"},
1161         {Opt_resize, "resize"},
1162         {Opt_delalloc, "delalloc"},
1163         {Opt_nodelalloc, "nodelalloc"},
1164         {Opt_block_validity, "block_validity"},
1165         {Opt_noblock_validity, "noblock_validity"},
1166         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1167         {Opt_journal_ioprio, "journal_ioprio=%u"},
1168         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1169         {Opt_auto_da_alloc, "auto_da_alloc"},
1170         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1171         {Opt_discard, "discard"},
1172         {Opt_nodiscard, "nodiscard"},
1173         {Opt_err, NULL},
1174 };
1175
1176 static ext4_fsblk_t get_sb_block(void **data)
1177 {
1178         ext4_fsblk_t    sb_block;
1179         char            *options = (char *) *data;
1180
1181         if (!options || strncmp(options, "sb=", 3) != 0)
1182                 return 1;       /* Default location */
1183
1184         options += 3;
1185         /* TODO: use simple_strtoll with >32bit ext4 */
1186         sb_block = simple_strtoul(options, &options, 0);
1187         if (*options && *options != ',') {
1188                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1189                        (char *) *data);
1190                 return 1;
1191         }
1192         if (*options == ',')
1193                 options++;
1194         *data = (void *) options;
1195
1196         return sb_block;
1197 }
1198
1199 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1200
1201 static int parse_options(char *options, struct super_block *sb,
1202                          unsigned long *journal_devnum,
1203                          unsigned int *journal_ioprio,
1204                          ext4_fsblk_t *n_blocks_count, int is_remount)
1205 {
1206         struct ext4_sb_info *sbi = EXT4_SB(sb);
1207         char *p;
1208         substring_t args[MAX_OPT_ARGS];
1209         int data_opt = 0;
1210         int option;
1211 #ifdef CONFIG_QUOTA
1212         int qtype, qfmt;
1213         char *qname;
1214 #endif
1215
1216         if (!options)
1217                 return 1;
1218
1219         while ((p = strsep(&options, ",")) != NULL) {
1220                 int token;
1221                 if (!*p)
1222                         continue;
1223
1224                 token = match_token(p, tokens, args);
1225                 switch (token) {
1226                 case Opt_bsd_df:
1227                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1228                         break;
1229                 case Opt_minix_df:
1230                         set_opt(sbi->s_mount_opt, MINIX_DF);
1231                         break;
1232                 case Opt_grpid:
1233                         set_opt(sbi->s_mount_opt, GRPID);
1234                         break;
1235                 case Opt_nogrpid:
1236                         clear_opt(sbi->s_mount_opt, GRPID);
1237                         break;
1238                 case Opt_resuid:
1239                         if (match_int(&args[0], &option))
1240                                 return 0;
1241                         sbi->s_resuid = option;
1242                         break;
1243                 case Opt_resgid:
1244                         if (match_int(&args[0], &option))
1245                                 return 0;
1246                         sbi->s_resgid = option;
1247                         break;
1248                 case Opt_sb:
1249                         /* handled by get_sb_block() instead of here */
1250                         /* *sb_block = match_int(&args[0]); */
1251                         break;
1252                 case Opt_err_panic:
1253                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1254                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1255                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1256                         break;
1257                 case Opt_err_ro:
1258                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1259                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1260                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1261                         break;
1262                 case Opt_err_cont:
1263                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1264                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1265                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1266                         break;
1267                 case Opt_nouid32:
1268                         set_opt(sbi->s_mount_opt, NO_UID32);
1269                         break;
1270                 case Opt_debug:
1271                         set_opt(sbi->s_mount_opt, DEBUG);
1272                         break;
1273                 case Opt_oldalloc:
1274                         set_opt(sbi->s_mount_opt, OLDALLOC);
1275                         break;
1276                 case Opt_orlov:
1277                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1278                         break;
1279 #ifdef CONFIG_EXT4_FS_XATTR
1280                 case Opt_user_xattr:
1281                         set_opt(sbi->s_mount_opt, XATTR_USER);
1282                         break;
1283                 case Opt_nouser_xattr:
1284                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1285                         break;
1286 #else
1287                 case Opt_user_xattr:
1288                 case Opt_nouser_xattr:
1289                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1290                         break;
1291 #endif
1292 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1293                 case Opt_acl:
1294                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1295                         break;
1296                 case Opt_noacl:
1297                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1298                         break;
1299 #else
1300                 case Opt_acl:
1301                 case Opt_noacl:
1302                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1303                         break;
1304 #endif
1305                 case Opt_journal_update:
1306                         /* @@@ FIXME */
1307                         /* Eventually we will want to be able to create
1308                            a journal file here.  For now, only allow the
1309                            user to specify an existing inode to be the
1310                            journal file. */
1311                         if (is_remount) {
1312                                 ext4_msg(sb, KERN_ERR,
1313                                          "Cannot specify journal on remount");
1314                                 return 0;
1315                         }
1316                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1317                         break;
1318                 case Opt_journal_dev:
1319                         if (is_remount) {
1320                                 ext4_msg(sb, KERN_ERR,
1321                                         "Cannot specify journal on remount");
1322                                 return 0;
1323                         }
1324                         if (match_int(&args[0], &option))
1325                                 return 0;
1326                         *journal_devnum = option;
1327                         break;
1328                 case Opt_journal_checksum:
1329                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1330                         break;
1331                 case Opt_journal_async_commit:
1332                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1333                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1334                         break;
1335                 case Opt_noload:
1336                         set_opt(sbi->s_mount_opt, NOLOAD);
1337                         break;
1338                 case Opt_commit:
1339                         if (match_int(&args[0], &option))
1340                                 return 0;
1341                         if (option < 0)
1342                                 return 0;
1343                         if (option == 0)
1344                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1345                         sbi->s_commit_interval = HZ * option;
1346                         break;
1347                 case Opt_max_batch_time:
1348                         if (match_int(&args[0], &option))
1349                                 return 0;
1350                         if (option < 0)
1351                                 return 0;
1352                         if (option == 0)
1353                                 option = EXT4_DEF_MAX_BATCH_TIME;
1354                         sbi->s_max_batch_time = option;
1355                         break;
1356                 case Opt_min_batch_time:
1357                         if (match_int(&args[0], &option))
1358                                 return 0;
1359                         if (option < 0)
1360                                 return 0;
1361                         sbi->s_min_batch_time = option;
1362                         break;
1363                 case Opt_data_journal:
1364                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1365                         goto datacheck;
1366                 case Opt_data_ordered:
1367                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1368                         goto datacheck;
1369                 case Opt_data_writeback:
1370                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1371                 datacheck:
1372                         if (is_remount) {
1373                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1374                                                 != data_opt) {
1375                                         ext4_msg(sb, KERN_ERR,
1376                                                 "Cannot change data mode on remount");
1377                                         return 0;
1378                                 }
1379                         } else {
1380                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1381                                 sbi->s_mount_opt |= data_opt;
1382                         }
1383                         break;
1384                 case Opt_data_err_abort:
1385                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1386                         break;
1387                 case Opt_data_err_ignore:
1388                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1389                         break;
1390 #ifdef CONFIG_QUOTA
1391                 case Opt_usrjquota:
1392                         qtype = USRQUOTA;
1393                         goto set_qf_name;
1394                 case Opt_grpjquota:
1395                         qtype = GRPQUOTA;
1396 set_qf_name:
1397                         if (sb_any_quota_loaded(sb) &&
1398                             !sbi->s_qf_names[qtype]) {
1399                                 ext4_msg(sb, KERN_ERR,
1400                                        "Cannot change journaled "
1401                                        "quota options when quota turned on");
1402                                 return 0;
1403                         }
1404                         qname = match_strdup(&args[0]);
1405                         if (!qname) {
1406                                 ext4_msg(sb, KERN_ERR,
1407                                         "Not enough memory for "
1408                                         "storing quotafile name");
1409                                 return 0;
1410                         }
1411                         if (sbi->s_qf_names[qtype] &&
1412                             strcmp(sbi->s_qf_names[qtype], qname)) {
1413                                 ext4_msg(sb, KERN_ERR,
1414                                         "%s quota file already "
1415                                         "specified", QTYPE2NAME(qtype));
1416                                 kfree(qname);
1417                                 return 0;
1418                         }
1419                         sbi->s_qf_names[qtype] = qname;
1420                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1421                                 ext4_msg(sb, KERN_ERR,
1422                                         "quotafile must be on "
1423                                         "filesystem root");
1424                                 kfree(sbi->s_qf_names[qtype]);
1425                                 sbi->s_qf_names[qtype] = NULL;
1426                                 return 0;
1427                         }
1428                         set_opt(sbi->s_mount_opt, QUOTA);
1429                         break;
1430                 case Opt_offusrjquota:
1431                         qtype = USRQUOTA;
1432                         goto clear_qf_name;
1433                 case Opt_offgrpjquota:
1434                         qtype = GRPQUOTA;
1435 clear_qf_name:
1436                         if (sb_any_quota_loaded(sb) &&
1437                             sbi->s_qf_names[qtype]) {
1438                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1439                                         "journaled quota options when "
1440                                         "quota turned on");
1441                                 return 0;
1442                         }
1443                         /*
1444                          * The space will be released later when all options
1445                          * are confirmed to be correct
1446                          */
1447                         sbi->s_qf_names[qtype] = NULL;
1448                         break;
1449                 case Opt_jqfmt_vfsold:
1450                         qfmt = QFMT_VFS_OLD;
1451                         goto set_qf_format;
1452                 case Opt_jqfmt_vfsv0:
1453                         qfmt = QFMT_VFS_V0;
1454                         goto set_qf_format;
1455                 case Opt_jqfmt_vfsv1:
1456                         qfmt = QFMT_VFS_V1;
1457 set_qf_format:
1458                         if (sb_any_quota_loaded(sb) &&
1459                             sbi->s_jquota_fmt != qfmt) {
1460                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1461                                         "journaled quota options when "
1462                                         "quota turned on");
1463                                 return 0;
1464                         }
1465                         sbi->s_jquota_fmt = qfmt;
1466                         break;
1467                 case Opt_quota:
1468                 case Opt_usrquota:
1469                         set_opt(sbi->s_mount_opt, QUOTA);
1470                         set_opt(sbi->s_mount_opt, USRQUOTA);
1471                         break;
1472                 case Opt_grpquota:
1473                         set_opt(sbi->s_mount_opt, QUOTA);
1474                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1475                         break;
1476                 case Opt_noquota:
1477                         if (sb_any_quota_loaded(sb)) {
1478                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1479                                         "options when quota turned on");
1480                                 return 0;
1481                         }
1482                         clear_opt(sbi->s_mount_opt, QUOTA);
1483                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1484                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1485                         break;
1486 #else
1487                 case Opt_quota:
1488                 case Opt_usrquota:
1489                 case Opt_grpquota:
1490                         ext4_msg(sb, KERN_ERR,
1491                                 "quota options not supported");
1492                         break;
1493                 case Opt_usrjquota:
1494                 case Opt_grpjquota:
1495                 case Opt_offusrjquota:
1496                 case Opt_offgrpjquota:
1497                 case Opt_jqfmt_vfsold:
1498                 case Opt_jqfmt_vfsv0:
1499                 case Opt_jqfmt_vfsv1:
1500                         ext4_msg(sb, KERN_ERR,
1501                                 "journaled quota options not supported");
1502                         break;
1503                 case Opt_noquota:
1504                         break;
1505 #endif
1506                 case Opt_abort:
1507                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1508                         break;
1509                 case Opt_nobarrier:
1510                         clear_opt(sbi->s_mount_opt, BARRIER);
1511                         break;
1512                 case Opt_barrier:
1513                         if (match_int(&args[0], &option)) {
1514                                 set_opt(sbi->s_mount_opt, BARRIER);
1515                                 break;
1516                         }
1517                         if (option)
1518                                 set_opt(sbi->s_mount_opt, BARRIER);
1519                         else
1520                                 clear_opt(sbi->s_mount_opt, BARRIER);
1521                         break;
1522                 case Opt_ignore:
1523                         break;
1524                 case Opt_resize:
1525                         if (!is_remount) {
1526                                 ext4_msg(sb, KERN_ERR,
1527                                         "resize option only available "
1528                                         "for remount");
1529                                 return 0;
1530                         }
1531                         if (match_int(&args[0], &option) != 0)
1532                                 return 0;
1533                         *n_blocks_count = option;
1534                         break;
1535                 case Opt_nobh:
1536                         set_opt(sbi->s_mount_opt, NOBH);
1537                         break;
1538                 case Opt_bh:
1539                         clear_opt(sbi->s_mount_opt, NOBH);
1540                         break;
1541                 case Opt_i_version:
1542                         set_opt(sbi->s_mount_opt, I_VERSION);
1543                         sb->s_flags |= MS_I_VERSION;
1544                         break;
1545                 case Opt_nodelalloc:
1546                         clear_opt(sbi->s_mount_opt, DELALLOC);
1547                         break;
1548                 case Opt_stripe:
1549                         if (match_int(&args[0], &option))
1550                                 return 0;
1551                         if (option < 0)
1552                                 return 0;
1553                         sbi->s_stripe = option;
1554                         break;
1555                 case Opt_delalloc:
1556                         set_opt(sbi->s_mount_opt, DELALLOC);
1557                         break;
1558                 case Opt_block_validity:
1559                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1560                         break;
1561                 case Opt_noblock_validity:
1562                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1563                         break;
1564                 case Opt_inode_readahead_blks:
1565                         if (match_int(&args[0], &option))
1566                                 return 0;
1567                         if (option < 0 || option > (1 << 30))
1568                                 return 0;
1569                         if (!is_power_of_2(option)) {
1570                                 ext4_msg(sb, KERN_ERR,
1571                                          "EXT4-fs: inode_readahead_blks"
1572                                          " must be a power of 2");
1573                                 return 0;
1574                         }
1575                         sbi->s_inode_readahead_blks = option;
1576                         break;
1577                 case Opt_journal_ioprio:
1578                         if (match_int(&args[0], &option))
1579                                 return 0;
1580                         if (option < 0 || option > 7)
1581                                 break;
1582                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1583                                                             option);
1584                         break;
1585                 case Opt_noauto_da_alloc:
1586                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1587                         break;
1588                 case Opt_auto_da_alloc:
1589                         if (match_int(&args[0], &option)) {
1590                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1591                                 break;
1592                         }
1593                         if (option)
1594                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1595                         else
1596                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1597                         break;
1598                 case Opt_discard:
1599                         set_opt(sbi->s_mount_opt, DISCARD);
1600                         break;
1601                 case Opt_nodiscard:
1602                         clear_opt(sbi->s_mount_opt, DISCARD);
1603                         break;
1604                 default:
1605                         ext4_msg(sb, KERN_ERR,
1606                                "Unrecognized mount option \"%s\" "
1607                                "or missing value", p);
1608                         return 0;
1609                 }
1610         }
1611 #ifdef CONFIG_QUOTA
1612         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1613                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1614                      sbi->s_qf_names[USRQUOTA])
1615                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1616
1617                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1618                      sbi->s_qf_names[GRPQUOTA])
1619                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1620
1621                 if ((sbi->s_qf_names[USRQUOTA] &&
1622                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1623                     (sbi->s_qf_names[GRPQUOTA] &&
1624                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1625                         ext4_msg(sb, KERN_ERR, "old and new quota "
1626                                         "format mixing");
1627                         return 0;
1628                 }
1629
1630                 if (!sbi->s_jquota_fmt) {
1631                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1632                                         "not specified");
1633                         return 0;
1634                 }
1635         } else {
1636                 if (sbi->s_jquota_fmt) {
1637                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1638                                         "specified with no journaling "
1639                                         "enabled");
1640                         return 0;
1641                 }
1642         }
1643 #endif
1644         return 1;
1645 }
1646
1647 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1648                             int read_only)
1649 {
1650         struct ext4_sb_info *sbi = EXT4_SB(sb);
1651         int res = 0;
1652
1653         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1654                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1655                          "forcing read-only mode");
1656                 res = MS_RDONLY;
1657         }
1658         if (read_only)
1659                 return res;
1660         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1661                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1662                          "running e2fsck is recommended");
1663         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1664                 ext4_msg(sb, KERN_WARNING,
1665                          "warning: mounting fs with errors, "
1666                          "running e2fsck is recommended");
1667         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1668                  le16_to_cpu(es->s_mnt_count) >=
1669                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1670                 ext4_msg(sb, KERN_WARNING,
1671                          "warning: maximal mount count reached, "
1672                          "running e2fsck is recommended");
1673         else if (le32_to_cpu(es->s_checkinterval) &&
1674                 (le32_to_cpu(es->s_lastcheck) +
1675                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1676                 ext4_msg(sb, KERN_WARNING,
1677                          "warning: checktime reached, "
1678                          "running e2fsck is recommended");
1679         if (!sbi->s_journal)
1680                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1681         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1682                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1683         le16_add_cpu(&es->s_mnt_count, 1);
1684         es->s_mtime = cpu_to_le32(get_seconds());
1685         ext4_update_dynamic_rev(sb);
1686         if (sbi->s_journal)
1687                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1688
1689         ext4_commit_super(sb, 1);
1690         if (test_opt(sb, DEBUG))
1691                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1692                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1693                         sb->s_blocksize,
1694                         sbi->s_groups_count,
1695                         EXT4_BLOCKS_PER_GROUP(sb),
1696                         EXT4_INODES_PER_GROUP(sb),
1697                         sbi->s_mount_opt);
1698
1699         return res;
1700 }
1701
1702 static int ext4_fill_flex_info(struct super_block *sb)
1703 {
1704         struct ext4_sb_info *sbi = EXT4_SB(sb);
1705         struct ext4_group_desc *gdp = NULL;
1706         ext4_group_t flex_group_count;
1707         ext4_group_t flex_group;
1708         int groups_per_flex = 0;
1709         size_t size;
1710         int i;
1711
1712         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1713         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1714
1715         if (groups_per_flex < 2) {
1716                 sbi->s_log_groups_per_flex = 0;
1717                 return 1;
1718         }
1719
1720         /* We allocate both existing and potentially added groups */
1721         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1722                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1723                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1724         size = flex_group_count * sizeof(struct flex_groups);
1725         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1726         if (sbi->s_flex_groups == NULL) {
1727                 sbi->s_flex_groups = vmalloc(size);
1728                 if (sbi->s_flex_groups)
1729                         memset(sbi->s_flex_groups, 0, size);
1730         }
1731         if (sbi->s_flex_groups == NULL) {
1732                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1733                                 "%u flex groups", flex_group_count);
1734                 goto failed;
1735         }
1736
1737         for (i = 0; i < sbi->s_groups_count; i++) {
1738                 gdp = ext4_get_group_desc(sb, i, NULL);
1739
1740                 flex_group = ext4_flex_group(sbi, i);
1741                 atomic_add(ext4_free_inodes_count(sb, gdp),
1742                            &sbi->s_flex_groups[flex_group].free_inodes);
1743                 atomic_add(ext4_free_blks_count(sb, gdp),
1744                            &sbi->s_flex_groups[flex_group].free_blocks);
1745                 atomic_add(ext4_used_dirs_count(sb, gdp),
1746                            &sbi->s_flex_groups[flex_group].used_dirs);
1747         }
1748
1749         return 1;
1750 failed:
1751         return 0;
1752 }
1753
1754 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1755                             struct ext4_group_desc *gdp)
1756 {
1757         __u16 crc = 0;
1758
1759         if (sbi->s_es->s_feature_ro_compat &
1760             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1761                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1762                 __le32 le_group = cpu_to_le32(block_group);
1763
1764                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1765                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1766                 crc = crc16(crc, (__u8 *)gdp, offset);
1767                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1768                 /* for checksum of struct ext4_group_desc do the rest...*/
1769                 if ((sbi->s_es->s_feature_incompat &
1770                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1771                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1772                         crc = crc16(crc, (__u8 *)gdp + offset,
1773                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1774                                         offset);
1775         }
1776
1777         return cpu_to_le16(crc);
1778 }
1779
1780 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1781                                 struct ext4_group_desc *gdp)
1782 {
1783         if ((sbi->s_es->s_feature_ro_compat &
1784              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1785             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1786                 return 0;
1787
1788         return 1;
1789 }
1790
1791 /* Called at mount-time, super-block is locked */
1792 static int ext4_check_descriptors(struct super_block *sb)
1793 {
1794         struct ext4_sb_info *sbi = EXT4_SB(sb);
1795         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1796         ext4_fsblk_t last_block;
1797         ext4_fsblk_t block_bitmap;
1798         ext4_fsblk_t inode_bitmap;
1799         ext4_fsblk_t inode_table;
1800         int flexbg_flag = 0;
1801         ext4_group_t i;
1802
1803         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1804                 flexbg_flag = 1;
1805
1806         ext4_debug("Checking group descriptors");
1807
1808         for (i = 0; i < sbi->s_groups_count; i++) {
1809                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1810
1811                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1812                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1813                 else
1814                         last_block = first_block +
1815                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1816
1817                 block_bitmap = ext4_block_bitmap(sb, gdp);
1818                 if (block_bitmap < first_block || block_bitmap > last_block) {
1819                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1820                                "Block bitmap for group %u not in group "
1821                                "(block %llu)!", i, block_bitmap);
1822                         return 0;
1823                 }
1824                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1825                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1826                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1827                                "Inode bitmap for group %u not in group "
1828                                "(block %llu)!", i, inode_bitmap);
1829                         return 0;
1830                 }
1831                 inode_table = ext4_inode_table(sb, gdp);
1832                 if (inode_table < first_block ||
1833                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1834                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1835                                "Inode table for group %u not in group "
1836                                "(block %llu)!", i, inode_table);
1837                         return 0;
1838                 }
1839                 ext4_lock_group(sb, i);
1840                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1841                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1842                                  "Checksum for group %u failed (%u!=%u)",
1843                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1844                                      gdp)), le16_to_cpu(gdp->bg_checksum));
1845                         if (!(sb->s_flags & MS_RDONLY)) {
1846                                 ext4_unlock_group(sb, i);
1847                                 return 0;
1848                         }
1849                 }
1850                 ext4_unlock_group(sb, i);
1851                 if (!flexbg_flag)
1852                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1853         }
1854
1855         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1856         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1857         return 1;
1858 }
1859
1860 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1861  * the superblock) which were deleted from all directories, but held open by
1862  * a process at the time of a crash.  We walk the list and try to delete these
1863  * inodes at recovery time (only with a read-write filesystem).
1864  *
1865  * In order to keep the orphan inode chain consistent during traversal (in
1866  * case of crash during recovery), we link each inode into the superblock
1867  * orphan list_head and handle it the same way as an inode deletion during
1868  * normal operation (which journals the operations for us).
1869  *
1870  * We only do an iget() and an iput() on each inode, which is very safe if we
1871  * accidentally point at an in-use or already deleted inode.  The worst that
1872  * can happen in this case is that we get a "bit already cleared" message from
1873  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1874  * e2fsck was run on this filesystem, and it must have already done the orphan
1875  * inode cleanup for us, so we can safely abort without any further action.
1876  */
1877 static void ext4_orphan_cleanup(struct super_block *sb,
1878                                 struct ext4_super_block *es)
1879 {
1880         unsigned int s_flags = sb->s_flags;
1881         int nr_orphans = 0, nr_truncates = 0;
1882 #ifdef CONFIG_QUOTA
1883         int i;
1884 #endif
1885         if (!es->s_last_orphan) {
1886                 jbd_debug(4, "no orphan inodes to clean up\n");
1887                 return;
1888         }
1889
1890         if (bdev_read_only(sb->s_bdev)) {
1891                 ext4_msg(sb, KERN_ERR, "write access "
1892                         "unavailable, skipping orphan cleanup");
1893                 return;
1894         }
1895
1896         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1897                 if (es->s_last_orphan)
1898                         jbd_debug(1, "Errors on filesystem, "
1899                                   "clearing orphan list.\n");
1900                 es->s_last_orphan = 0;
1901                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1902                 return;
1903         }
1904
1905         if (s_flags & MS_RDONLY) {
1906                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
1907                 sb->s_flags &= ~MS_RDONLY;
1908         }
1909 #ifdef CONFIG_QUOTA
1910         /* Needed for iput() to work correctly and not trash data */
1911         sb->s_flags |= MS_ACTIVE;
1912         /* Turn on quotas so that they are updated correctly */
1913         for (i = 0; i < MAXQUOTAS; i++) {
1914                 if (EXT4_SB(sb)->s_qf_names[i]) {
1915                         int ret = ext4_quota_on_mount(sb, i);
1916                         if (ret < 0)
1917                                 ext4_msg(sb, KERN_ERR,
1918                                         "Cannot turn on journaled "
1919                                         "quota: error %d", ret);
1920                 }
1921         }
1922 #endif
1923
1924         while (es->s_last_orphan) {
1925                 struct inode *inode;
1926
1927                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1928                 if (IS_ERR(inode)) {
1929                         es->s_last_orphan = 0;
1930                         break;
1931                 }
1932
1933                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1934                 vfs_dq_init(inode);
1935                 if (inode->i_nlink) {
1936                         ext4_msg(sb, KERN_DEBUG,
1937                                 "%s: truncating inode %lu to %lld bytes",
1938                                 __func__, inode->i_ino, inode->i_size);
1939                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1940                                   inode->i_ino, inode->i_size);
1941                         ext4_truncate(inode);
1942                         nr_truncates++;
1943                 } else {
1944                         ext4_msg(sb, KERN_DEBUG,
1945                                 "%s: deleting unreferenced inode %lu",
1946                                 __func__, inode->i_ino);
1947                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1948                                   inode->i_ino);
1949                         nr_orphans++;
1950                 }
1951                 iput(inode);  /* The delete magic happens here! */
1952         }
1953
1954 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1955
1956         if (nr_orphans)
1957                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
1958                        PLURAL(nr_orphans));
1959         if (nr_truncates)
1960                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
1961                        PLURAL(nr_truncates));
1962 #ifdef CONFIG_QUOTA
1963         /* Turn quotas off */
1964         for (i = 0; i < MAXQUOTAS; i++) {
1965                 if (sb_dqopt(sb)->files[i])
1966                         vfs_quota_off(sb, i, 0);
1967         }
1968 #endif
1969         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1970 }
1971
1972 /*
1973  * Maximal extent format file size.
1974  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1975  * extent format containers, within a sector_t, and within i_blocks
1976  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1977  * so that won't be a limiting factor.
1978  *
1979  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1980  */
1981 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1982 {
1983         loff_t res;
1984         loff_t upper_limit = MAX_LFS_FILESIZE;
1985
1986         /* small i_blocks in vfs inode? */
1987         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1988                 /*
1989                  * CONFIG_LBDAF is not enabled implies the inode
1990                  * i_block represent total blocks in 512 bytes
1991                  * 32 == size of vfs inode i_blocks * 8
1992                  */
1993                 upper_limit = (1LL << 32) - 1;
1994
1995                 /* total blocks in file system block size */
1996                 upper_limit >>= (blkbits - 9);
1997                 upper_limit <<= blkbits;
1998         }
1999
2000         /* 32-bit extent-start container, ee_block */
2001         res = 1LL << 32;
2002         res <<= blkbits;
2003         res -= 1;
2004
2005         /* Sanity check against vm- & vfs- imposed limits */
2006         if (res > upper_limit)
2007                 res = upper_limit;
2008
2009         return res;
2010 }
2011
2012 /*
2013  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2014  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2015  * We need to be 1 filesystem block less than the 2^48 sector limit.
2016  */
2017 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2018 {
2019         loff_t res = EXT4_NDIR_BLOCKS;
2020         int meta_blocks;
2021         loff_t upper_limit;
2022         /* This is calculated to be the largest file size for a dense, block
2023          * mapped file such that the file's total number of 512-byte sectors,
2024          * including data and all indirect blocks, does not exceed (2^48 - 1).
2025          *
2026          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2027          * number of 512-byte sectors of the file.
2028          */
2029
2030         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2031                 /*
2032                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2033                  * the inode i_block field represents total file blocks in
2034                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2035                  */
2036                 upper_limit = (1LL << 32) - 1;
2037
2038                 /* total blocks in file system block size */
2039                 upper_limit >>= (bits - 9);
2040
2041         } else {
2042                 /*
2043                  * We use 48 bit ext4_inode i_blocks
2044                  * With EXT4_HUGE_FILE_FL set the i_blocks
2045                  * represent total number of blocks in
2046                  * file system block size
2047                  */
2048                 upper_limit = (1LL << 48) - 1;
2049
2050         }
2051
2052         /* indirect blocks */
2053         meta_blocks = 1;
2054         /* double indirect blocks */
2055         meta_blocks += 1 + (1LL << (bits-2));
2056         /* tripple indirect blocks */
2057         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2058
2059         upper_limit -= meta_blocks;
2060         upper_limit <<= bits;
2061
2062         res += 1LL << (bits-2);
2063         res += 1LL << (2*(bits-2));
2064         res += 1LL << (3*(bits-2));
2065         res <<= bits;
2066         if (res > upper_limit)
2067                 res = upper_limit;
2068
2069         if (res > MAX_LFS_FILESIZE)
2070                 res = MAX_LFS_FILESIZE;
2071
2072         return res;
2073 }
2074
2075 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2076                                    ext4_fsblk_t logical_sb_block, int nr)
2077 {
2078         struct ext4_sb_info *sbi = EXT4_SB(sb);
2079         ext4_group_t bg, first_meta_bg;
2080         int has_super = 0;
2081
2082         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2083
2084         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2085             nr < first_meta_bg)
2086                 return logical_sb_block + nr + 1;
2087         bg = sbi->s_desc_per_block * nr;
2088         if (ext4_bg_has_super(sb, bg))
2089                 has_super = 1;
2090
2091         return (has_super + ext4_group_first_block_no(sb, bg));
2092 }
2093
2094 /**
2095  * ext4_get_stripe_size: Get the stripe size.
2096  * @sbi: In memory super block info
2097  *
2098  * If we have specified it via mount option, then
2099  * use the mount option value. If the value specified at mount time is
2100  * greater than the blocks per group use the super block value.
2101  * If the super block value is greater than blocks per group return 0.
2102  * Allocator needs it be less than blocks per group.
2103  *
2104  */
2105 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2106 {
2107         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2108         unsigned long stripe_width =
2109                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2110
2111         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2112                 return sbi->s_stripe;
2113
2114         if (stripe_width <= sbi->s_blocks_per_group)
2115                 return stripe_width;
2116
2117         if (stride <= sbi->s_blocks_per_group)
2118                 return stride;
2119
2120         return 0;
2121 }
2122
2123 /* sysfs supprt */
2124
2125 struct ext4_attr {
2126         struct attribute attr;
2127         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2128         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *, 
2129                          const char *, size_t);
2130         int offset;
2131 };
2132
2133 static int parse_strtoul(const char *buf,
2134                 unsigned long max, unsigned long *value)
2135 {
2136         char *endp;
2137
2138         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2139         endp = skip_spaces(endp);
2140         if (*endp || *value > max)
2141                 return -EINVAL;
2142
2143         return 0;
2144 }
2145
2146 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2147                                               struct ext4_sb_info *sbi,
2148                                               char *buf)
2149 {
2150         return snprintf(buf, PAGE_SIZE, "%llu\n",
2151                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2152 }
2153
2154 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2155                                          struct ext4_sb_info *sbi, char *buf)
2156 {
2157         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2158
2159         return snprintf(buf, PAGE_SIZE, "%lu\n",
2160                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2161                          sbi->s_sectors_written_start) >> 1);
2162 }
2163
2164 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2165                                           struct ext4_sb_info *sbi, char *buf)
2166 {
2167         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2168
2169         return snprintf(buf, PAGE_SIZE, "%llu\n",
2170                         (unsigned long long)(sbi->s_kbytes_written +
2171                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2172                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2173 }
2174
2175 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2176                                           struct ext4_sb_info *sbi,
2177                                           const char *buf, size_t count)
2178 {
2179         unsigned long t;
2180
2181         if (parse_strtoul(buf, 0x40000000, &t))
2182                 return -EINVAL;
2183
2184         if (!is_power_of_2(t))
2185                 return -EINVAL;
2186
2187         sbi->s_inode_readahead_blks = t;
2188         return count;
2189 }
2190
2191 static ssize_t sbi_ui_show(struct ext4_attr *a,
2192                            struct ext4_sb_info *sbi, char *buf)
2193 {
2194         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2195
2196         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2197 }
2198
2199 static ssize_t sbi_ui_store(struct ext4_attr *a,
2200                             struct ext4_sb_info *sbi,
2201                             const char *buf, size_t count)
2202 {
2203         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2204         unsigned long t;
2205
2206         if (parse_strtoul(buf, 0xffffffff, &t))
2207                 return -EINVAL;
2208         *ui = t;
2209         return count;
2210 }
2211
2212 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2213 static struct ext4_attr ext4_attr_##_name = {                   \
2214         .attr = {.name = __stringify(_name), .mode = _mode },   \
2215         .show   = _show,                                        \
2216         .store  = _store,                                       \
2217         .offset = offsetof(struct ext4_sb_info, _elname),       \
2218 }
2219 #define EXT4_ATTR(name, mode, show, store) \
2220 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2221
2222 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2223 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2224 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2225         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2226 #define ATTR_LIST(name) &ext4_attr_##name.attr
2227
2228 EXT4_RO_ATTR(delayed_allocation_blocks);
2229 EXT4_RO_ATTR(session_write_kbytes);
2230 EXT4_RO_ATTR(lifetime_write_kbytes);
2231 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2232                  inode_readahead_blks_store, s_inode_readahead_blks);
2233 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2234 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2235 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2236 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2237 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2238 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2239 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2240 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2241
2242 static struct attribute *ext4_attrs[] = {
2243         ATTR_LIST(delayed_allocation_blocks),
2244         ATTR_LIST(session_write_kbytes),
2245         ATTR_LIST(lifetime_write_kbytes),
2246         ATTR_LIST(inode_readahead_blks),
2247         ATTR_LIST(inode_goal),
2248         ATTR_LIST(mb_stats),
2249         ATTR_LIST(mb_max_to_scan),
2250         ATTR_LIST(mb_min_to_scan),
2251         ATTR_LIST(mb_order2_req),
2252         ATTR_LIST(mb_stream_req),
2253         ATTR_LIST(mb_group_prealloc),
2254         ATTR_LIST(max_writeback_mb_bump),
2255         NULL,
2256 };
2257
2258 static ssize_t ext4_attr_show(struct kobject *kobj,
2259                               struct attribute *attr, char *buf)
2260 {
2261         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2262                                                 s_kobj);
2263         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2264
2265         return a->show ? a->show(a, sbi, buf) : 0;
2266 }
2267
2268 static ssize_t ext4_attr_store(struct kobject *kobj,
2269                                struct attribute *attr,
2270                                const char *buf, size_t len)
2271 {
2272         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2273                                                 s_kobj);
2274         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2275
2276         return a->store ? a->store(a, sbi, buf, len) : 0;
2277 }
2278
2279 static void ext4_sb_release(struct kobject *kobj)
2280 {
2281         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2282                                                 s_kobj);
2283         complete(&sbi->s_kobj_unregister);
2284 }
2285
2286
2287 static struct sysfs_ops ext4_attr_ops = {
2288         .show   = ext4_attr_show,
2289         .store  = ext4_attr_store,
2290 };
2291
2292 static struct kobj_type ext4_ktype = {
2293         .default_attrs  = ext4_attrs,
2294         .sysfs_ops      = &ext4_attr_ops,
2295         .release        = ext4_sb_release,
2296 };
2297
2298 /*
2299  * Check whether this filesystem can be mounted based on
2300  * the features present and the RDONLY/RDWR mount requested.
2301  * Returns 1 if this filesystem can be mounted as requested,
2302  * 0 if it cannot be.
2303  */
2304 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2305 {
2306         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2307                 ext4_msg(sb, KERN_ERR,
2308                         "Couldn't mount because of "
2309                         "unsupported optional features (%x)",
2310                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2311                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2312                 return 0;
2313         }
2314
2315         if (readonly)
2316                 return 1;
2317
2318         /* Check that feature set is OK for a read-write mount */
2319         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2320                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2321                          "unsupported optional features (%x)",
2322                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2323                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2324                 return 0;
2325         }
2326         /*
2327          * Large file size enabled file system can only be mounted
2328          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2329          */
2330         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2331                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2332                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2333                                  "cannot be mounted RDWR without "
2334                                  "CONFIG_LBDAF");
2335                         return 0;
2336                 }
2337         }
2338         return 1;
2339 }
2340
2341 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2342                                 __releases(kernel_lock)
2343                                 __acquires(kernel_lock)
2344 {
2345         struct buffer_head *bh;
2346         struct ext4_super_block *es = NULL;
2347         struct ext4_sb_info *sbi;
2348         ext4_fsblk_t block;
2349         ext4_fsblk_t sb_block = get_sb_block(&data);
2350         ext4_fsblk_t logical_sb_block;
2351         unsigned long offset = 0;
2352         unsigned long journal_devnum = 0;
2353         unsigned long def_mount_opts;
2354         struct inode *root;
2355         char *cp;
2356         const char *descr;
2357         int ret = -EINVAL;
2358         int blocksize;
2359         unsigned int db_count;
2360         unsigned int i;
2361         int needs_recovery, has_huge_files;
2362         __u64 blocks_count;
2363         int err;
2364         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2365
2366         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2367         if (!sbi)
2368                 return -ENOMEM;
2369
2370         sbi->s_blockgroup_lock =
2371                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2372         if (!sbi->s_blockgroup_lock) {
2373                 kfree(sbi);
2374                 return -ENOMEM;
2375         }
2376         sb->s_fs_info = sbi;
2377         sbi->s_mount_opt = 0;
2378         sbi->s_resuid = EXT4_DEF_RESUID;
2379         sbi->s_resgid = EXT4_DEF_RESGID;
2380         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2381         sbi->s_sb_block = sb_block;
2382         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2383                                                       sectors[1]);
2384
2385         unlock_kernel();
2386
2387         /* Cleanup superblock name */
2388         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2389                 *cp = '!';
2390
2391         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2392         if (!blocksize) {
2393                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2394                 goto out_fail;
2395         }
2396
2397         /*
2398          * The ext4 superblock will not be buffer aligned for other than 1kB
2399          * block sizes.  We need to calculate the offset from buffer start.
2400          */
2401         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2402                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2403                 offset = do_div(logical_sb_block, blocksize);
2404         } else {
2405                 logical_sb_block = sb_block;
2406         }
2407
2408         if (!(bh = sb_bread(sb, logical_sb_block))) {
2409                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2410                 goto out_fail;
2411         }
2412         /*
2413          * Note: s_es must be initialized as soon as possible because
2414          *       some ext4 macro-instructions depend on its value
2415          */
2416         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2417         sbi->s_es = es;
2418         sb->s_magic = le16_to_cpu(es->s_magic);
2419         if (sb->s_magic != EXT4_SUPER_MAGIC)
2420                 goto cantfind_ext4;
2421         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2422
2423         /* Set defaults before we parse the mount options */
2424         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2425         if (def_mount_opts & EXT4_DEFM_DEBUG)
2426                 set_opt(sbi->s_mount_opt, DEBUG);
2427         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
2428                 set_opt(sbi->s_mount_opt, GRPID);
2429         if (def_mount_opts & EXT4_DEFM_UID16)
2430                 set_opt(sbi->s_mount_opt, NO_UID32);
2431 #ifdef CONFIG_EXT4_FS_XATTR
2432         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2433                 set_opt(sbi->s_mount_opt, XATTR_USER);
2434 #endif
2435 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2436         if (def_mount_opts & EXT4_DEFM_ACL)
2437                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2438 #endif
2439         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2440                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2441         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2442                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2443         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2444                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2445
2446         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2447                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2448         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2449                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2450         else
2451                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2452
2453         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2454         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2455         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2456         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2457         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2458
2459         set_opt(sbi->s_mount_opt, BARRIER);
2460
2461         /*
2462          * enable delayed allocation by default
2463          * Use -o nodelalloc to turn it off
2464          */
2465         set_opt(sbi->s_mount_opt, DELALLOC);
2466
2467         if (!parse_options((char *) data, sb, &journal_devnum,
2468                            &journal_ioprio, NULL, 0))
2469                 goto failed_mount;
2470
2471         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2472                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2473
2474         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2475             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2476              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2477              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2478                 ext4_msg(sb, KERN_WARNING,
2479                        "feature flags set on rev 0 fs, "
2480                        "running e2fsck is recommended");
2481
2482         /*
2483          * Check feature flags regardless of the revision level, since we
2484          * previously didn't change the revision level when setting the flags,
2485          * so there is a chance incompat flags are set on a rev 0 filesystem.
2486          */
2487         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
2488                 goto failed_mount;
2489
2490         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2491
2492         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2493             blocksize > EXT4_MAX_BLOCK_SIZE) {
2494                 ext4_msg(sb, KERN_ERR,
2495                        "Unsupported filesystem blocksize %d", blocksize);
2496                 goto failed_mount;
2497         }
2498
2499         if (sb->s_blocksize != blocksize) {
2500                 /* Validate the filesystem blocksize */
2501                 if (!sb_set_blocksize(sb, blocksize)) {
2502                         ext4_msg(sb, KERN_ERR, "bad block size %d",
2503                                         blocksize);
2504                         goto failed_mount;
2505                 }
2506
2507                 brelse(bh);
2508                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2509                 offset = do_div(logical_sb_block, blocksize);
2510                 bh = sb_bread(sb, logical_sb_block);
2511                 if (!bh) {
2512                         ext4_msg(sb, KERN_ERR,
2513                                "Can't read superblock on 2nd try");
2514                         goto failed_mount;
2515                 }
2516                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2517                 sbi->s_es = es;
2518                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2519                         ext4_msg(sb, KERN_ERR,
2520                                "Magic mismatch, very weird!");
2521                         goto failed_mount;
2522                 }
2523         }
2524
2525         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2526                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2527         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2528                                                       has_huge_files);
2529         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2530
2531         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2532                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2533                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2534         } else {
2535                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2536                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2537                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2538                     (!is_power_of_2(sbi->s_inode_size)) ||
2539                     (sbi->s_inode_size > blocksize)) {
2540                         ext4_msg(sb, KERN_ERR,
2541                                "unsupported inode size: %d",
2542                                sbi->s_inode_size);
2543                         goto failed_mount;
2544                 }
2545                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2546                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2547         }
2548
2549         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2550         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2551                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2552                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2553                     !is_power_of_2(sbi->s_desc_size)) {
2554                         ext4_msg(sb, KERN_ERR,
2555                                "unsupported descriptor size %lu",
2556                                sbi->s_desc_size);
2557                         goto failed_mount;
2558                 }
2559         } else
2560                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2561
2562         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2563         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2564         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2565                 goto cantfind_ext4;
2566
2567         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2568         if (sbi->s_inodes_per_block == 0)
2569                 goto cantfind_ext4;
2570         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2571                                         sbi->s_inodes_per_block;
2572         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2573         sbi->s_sbh = bh;
2574         sbi->s_mount_state = le16_to_cpu(es->s_state);
2575         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2576         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2577
2578         for (i = 0; i < 4; i++)
2579                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2580         sbi->s_def_hash_version = es->s_def_hash_version;
2581         i = le32_to_cpu(es->s_flags);
2582         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2583                 sbi->s_hash_unsigned = 3;
2584         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2585 #ifdef __CHAR_UNSIGNED__
2586                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2587                 sbi->s_hash_unsigned = 3;
2588 #else
2589                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2590 #endif
2591                 sb->s_dirt = 1;
2592         }
2593
2594         if (sbi->s_blocks_per_group > blocksize * 8) {
2595                 ext4_msg(sb, KERN_ERR,
2596                        "#blocks per group too big: %lu",
2597                        sbi->s_blocks_per_group);
2598                 goto failed_mount;
2599         }
2600         if (sbi->s_inodes_per_group > blocksize * 8) {
2601                 ext4_msg(sb, KERN_ERR,
2602                        "#inodes per group too big: %lu",
2603                        sbi->s_inodes_per_group);
2604                 goto failed_mount;
2605         }
2606
2607         /*
2608          * Test whether we have more sectors than will fit in sector_t,
2609          * and whether the max offset is addressable by the page cache.
2610          */
2611         if ((ext4_blocks_count(es) >
2612              (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
2613             (ext4_blocks_count(es) >
2614              (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
2615                 ext4_msg(sb, KERN_ERR, "filesystem"
2616                          " too large to mount safely on this system");
2617                 if (sizeof(sector_t) < 8)
2618                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
2619                 ret = -EFBIG;
2620                 goto failed_mount;
2621         }
2622
2623         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2624                 goto cantfind_ext4;
2625
2626         /* check blocks count against device size */
2627         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2628         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2629                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2630                        "exceeds size of device (%llu blocks)",
2631                        ext4_blocks_count(es), blocks_count);
2632                 goto failed_mount;
2633         }
2634
2635         /*
2636          * It makes no sense for the first data block to be beyond the end
2637          * of the filesystem.
2638          */
2639         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2640                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2641                          "block %u is beyond end of filesystem (%llu)",
2642                          le32_to_cpu(es->s_first_data_block),
2643                          ext4_blocks_count(es));
2644                 goto failed_mount;
2645         }
2646         blocks_count = (ext4_blocks_count(es) -
2647                         le32_to_cpu(es->s_first_data_block) +
2648                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2649         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2650         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2651                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2652                        "(block count %llu, first data block %u, "
2653                        "blocks per group %lu)", sbi->s_groups_count,
2654                        ext4_blocks_count(es),
2655                        le32_to_cpu(es->s_first_data_block),
2656                        EXT4_BLOCKS_PER_GROUP(sb));
2657                 goto failed_mount;
2658         }
2659         sbi->s_groups_count = blocks_count;
2660         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
2661                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
2662         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2663                    EXT4_DESC_PER_BLOCK(sb);
2664         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2665                                     GFP_KERNEL);
2666         if (sbi->s_group_desc == NULL) {
2667                 ext4_msg(sb, KERN_ERR, "not enough memory");
2668                 goto failed_mount;
2669         }
2670
2671 #ifdef CONFIG_PROC_FS
2672         if (ext4_proc_root)
2673                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2674 #endif
2675
2676         bgl_lock_init(sbi->s_blockgroup_lock);
2677
2678         for (i = 0; i < db_count; i++) {
2679                 block = descriptor_loc(sb, logical_sb_block, i);
2680                 sbi->s_group_desc[i] = sb_bread(sb, block);
2681                 if (!sbi->s_group_desc[i]) {
2682                         ext4_msg(sb, KERN_ERR,
2683                                "can't read group descriptor %d", i);
2684                         db_count = i;
2685                         goto failed_mount2;
2686                 }
2687         }
2688         if (!ext4_check_descriptors(sb)) {
2689                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2690                 goto failed_mount2;
2691         }
2692         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2693                 if (!ext4_fill_flex_info(sb)) {
2694                         ext4_msg(sb, KERN_ERR,
2695                                "unable to initialize "
2696                                "flex_bg meta info!");
2697                         goto failed_mount2;
2698                 }
2699
2700         sbi->s_gdb_count = db_count;
2701         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2702         spin_lock_init(&sbi->s_next_gen_lock);
2703
2704         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2705                         ext4_count_free_blocks(sb));
2706         if (!err) {
2707                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2708                                 ext4_count_free_inodes(sb));
2709         }
2710         if (!err) {
2711                 err = percpu_counter_init(&sbi->s_dirs_counter,
2712                                 ext4_count_dirs(sb));
2713         }
2714         if (!err) {
2715                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2716         }
2717         if (err) {
2718                 ext4_msg(sb, KERN_ERR, "insufficient memory");
2719                 goto failed_mount3;
2720         }
2721
2722         sbi->s_stripe = ext4_get_stripe_size(sbi);
2723         sbi->s_max_writeback_mb_bump = 128;
2724
2725         /*
2726          * set up enough so that it can read an inode
2727          */
2728         if (!test_opt(sb, NOLOAD) &&
2729             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2730                 sb->s_op = &ext4_sops;
2731         else
2732                 sb->s_op = &ext4_nojournal_sops;
2733         sb->s_export_op = &ext4_export_ops;
2734         sb->s_xattr = ext4_xattr_handlers;
2735 #ifdef CONFIG_QUOTA
2736         sb->s_qcop = &ext4_qctl_operations;
2737         sb->dq_op = &ext4_quota_operations;
2738 #endif
2739         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2740         mutex_init(&sbi->s_orphan_lock);
2741         mutex_init(&sbi->s_resize_lock);
2742
2743         sb->s_root = NULL;
2744
2745         needs_recovery = (es->s_last_orphan != 0 ||
2746                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2747                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2748
2749         /*
2750          * The first inode we look at is the journal inode.  Don't try
2751          * root first: it may be modified in the journal!
2752          */
2753         if (!test_opt(sb, NOLOAD) &&
2754             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2755                 if (ext4_load_journal(sb, es, journal_devnum))
2756                         goto failed_mount3;
2757         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2758               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2759                 ext4_msg(sb, KERN_ERR, "required journal recovery "
2760                        "suppressed and not mounted read-only");
2761                 goto failed_mount4;
2762         } else {
2763                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2764                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2765                 sbi->s_journal = NULL;
2766                 needs_recovery = 0;
2767                 goto no_journal;
2768         }
2769
2770         if (ext4_blocks_count(es) > 0xffffffffULL &&
2771             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2772                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2773                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
2774                 goto failed_mount4;
2775         }
2776
2777         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2778                 jbd2_journal_set_features(sbi->s_journal,
2779                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2780                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2781         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2782                 jbd2_journal_set_features(sbi->s_journal,
2783                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2784                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2785                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2786         } else {
2787                 jbd2_journal_clear_features(sbi->s_journal,
2788                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2789                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2790         }
2791
2792         /* We have now updated the journal if required, so we can
2793          * validate the data journaling mode. */
2794         switch (test_opt(sb, DATA_FLAGS)) {
2795         case 0:
2796                 /* No mode set, assume a default based on the journal
2797                  * capabilities: ORDERED_DATA if the journal can
2798                  * cope, else JOURNAL_DATA
2799                  */
2800                 if (jbd2_journal_check_available_features
2801                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2802                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2803                 else
2804                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2805                 break;
2806
2807         case EXT4_MOUNT_ORDERED_DATA:
2808         case EXT4_MOUNT_WRITEBACK_DATA:
2809                 if (!jbd2_journal_check_available_features
2810                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2811                         ext4_msg(sb, KERN_ERR, "Journal does not support "
2812                                "requested data journaling mode");
2813                         goto failed_mount4;
2814                 }
2815         default:
2816                 break;
2817         }
2818         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2819
2820 no_journal:
2821
2822         if (test_opt(sb, NOBH)) {
2823                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2824                         ext4_msg(sb, KERN_WARNING, "Ignoring nobh option - "
2825                                 "its supported only with writeback mode");
2826                         clear_opt(sbi->s_mount_opt, NOBH);
2827                 }
2828         }
2829         EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten");
2830         if (!EXT4_SB(sb)->dio_unwritten_wq) {
2831                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
2832                 goto failed_mount_wq;
2833         }
2834
2835         /*
2836          * The jbd2_journal_load will have done any necessary log recovery,
2837          * so we can safely mount the rest of the filesystem now.
2838          */
2839
2840         root = ext4_iget(sb, EXT4_ROOT_INO);
2841         if (IS_ERR(root)) {
2842                 ext4_msg(sb, KERN_ERR, "get root inode failed");
2843                 ret = PTR_ERR(root);
2844                 goto failed_mount4;
2845         }
2846         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2847                 iput(root);
2848                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
2849                 goto failed_mount4;
2850         }
2851         sb->s_root = d_alloc_root(root);
2852         if (!sb->s_root) {
2853                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
2854                 iput(root);
2855                 ret = -ENOMEM;
2856                 goto failed_mount4;
2857         }
2858
2859         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2860
2861         /* determine the minimum size of new large inodes, if present */
2862         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2863                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2864                                                      EXT4_GOOD_OLD_INODE_SIZE;
2865                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2866                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2867                         if (sbi->s_want_extra_isize <
2868                             le16_to_cpu(es->s_want_extra_isize))
2869                                 sbi->s_want_extra_isize =
2870                                         le16_to_cpu(es->s_want_extra_isize);
2871                         if (sbi->s_want_extra_isize <
2872                             le16_to_cpu(es->s_min_extra_isize))
2873                                 sbi->s_want_extra_isize =
2874                                         le16_to_cpu(es->s_min_extra_isize);
2875                 }
2876         }
2877         /* Check if enough inode space is available */
2878         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2879                                                         sbi->s_inode_size) {
2880                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2881                                                        EXT4_GOOD_OLD_INODE_SIZE;
2882                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
2883                          "available");
2884         }
2885
2886         if (test_opt(sb, DELALLOC) &&
2887             (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2888                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
2889                          "requested data journaling mode");
2890                 clear_opt(sbi->s_mount_opt, DELALLOC);
2891         }
2892
2893         err = ext4_setup_system_zone(sb);
2894         if (err) {
2895                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
2896                          "zone (%d)\n", err);
2897                 goto failed_mount4;
2898         }
2899
2900         ext4_ext_init(sb);
2901         err = ext4_mb_init(sb, needs_recovery);
2902         if (err) {
2903                 ext4_msg(sb, KERN_ERR, "failed to initalize mballoc (%d)",
2904                          err);
2905                 goto failed_mount4;
2906         }
2907
2908         sbi->s_kobj.kset = ext4_kset;
2909         init_completion(&sbi->s_kobj_unregister);
2910         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
2911                                    "%s", sb->s_id);
2912         if (err) {
2913                 ext4_mb_release(sb);
2914                 ext4_ext_release(sb);
2915                 goto failed_mount4;
2916         };
2917
2918         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2919         ext4_orphan_cleanup(sb, es);
2920         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2921         if (needs_recovery) {
2922                 ext4_msg(sb, KERN_INFO, "recovery complete");
2923                 ext4_mark_recovery_complete(sb, es);
2924         }
2925         if (EXT4_SB(sb)->s_journal) {
2926                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2927                         descr = " journalled data mode";
2928                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2929                         descr = " ordered data mode";
2930                 else
2931                         descr = " writeback data mode";
2932         } else
2933                 descr = "out journal";
2934
2935         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s", descr);
2936
2937         lock_kernel();
2938         return 0;
2939
2940 cantfind_ext4:
2941         if (!silent)
2942                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
2943         goto failed_mount;
2944
2945 failed_mount4:
2946         ext4_msg(sb, KERN_ERR, "mount failed");
2947         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
2948 failed_mount_wq:
2949         ext4_release_system_zone(sb);
2950         if (sbi->s_journal) {
2951                 jbd2_journal_destroy(sbi->s_journal);
2952                 sbi->s_journal = NULL;
2953         }
2954 failed_mount3:
2955         if (sbi->s_flex_groups) {
2956                 if (is_vmalloc_addr(sbi->s_flex_groups))
2957                         vfree(sbi->s_flex_groups);
2958                 else
2959                         kfree(sbi->s_flex_groups);
2960         }
2961         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2962         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2963         percpu_counter_destroy(&sbi->s_dirs_counter);
2964         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2965 failed_mount2:
2966         for (i = 0; i < db_count; i++)
2967                 brelse(sbi->s_group_desc[i]);
2968         kfree(sbi->s_group_desc);
2969 failed_mount:
2970         if (sbi->s_proc) {
2971                 remove_proc_entry(sb->s_id, ext4_proc_root);
2972         }
2973 #ifdef CONFIG_QUOTA
2974         for (i = 0; i < MAXQUOTAS; i++)
2975                 kfree(sbi->s_qf_names[i]);
2976 #endif
2977         ext4_blkdev_remove(sbi);
2978         brelse(bh);
2979 out_fail:
2980         sb->s_fs_info = NULL;
2981         kfree(sbi->s_blockgroup_lock);
2982         kfree(sbi);
2983         lock_kernel();
2984         return ret;
2985 }
2986
2987 /*
2988  * Setup any per-fs journal parameters now.  We'll do this both on
2989  * initial mount, once the journal has been initialised but before we've
2990  * done any recovery; and again on any subsequent remount.
2991  */
2992 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2993 {
2994         struct ext4_sb_info *sbi = EXT4_SB(sb);
2995
2996         journal->j_commit_interval = sbi->s_commit_interval;
2997         journal->j_min_batch_time = sbi->s_min_batch_time;
2998         journal->j_max_batch_time = sbi->s_max_batch_time;
2999
3000         spin_lock(&journal->j_state_lock);
3001         if (test_opt(sb, BARRIER))
3002                 journal->j_flags |= JBD2_BARRIER;
3003         else
3004                 journal->j_flags &= ~JBD2_BARRIER;
3005         if (test_opt(sb, DATA_ERR_ABORT))
3006                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3007         else
3008                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3009         spin_unlock(&journal->j_state_lock);
3010 }
3011
3012 static journal_t *ext4_get_journal(struct super_block *sb,
3013                                    unsigned int journal_inum)
3014 {
3015         struct inode *journal_inode;
3016         journal_t *journal;
3017
3018         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3019
3020         /* First, test for the existence of a valid inode on disk.  Bad
3021          * things happen if we iget() an unused inode, as the subsequent
3022          * iput() will try to delete it. */
3023
3024         journal_inode = ext4_iget(sb, journal_inum);
3025         if (IS_ERR(journal_inode)) {
3026                 ext4_msg(sb, KERN_ERR, "no journal found");
3027                 return NULL;
3028         }
3029         if (!journal_inode->i_nlink) {
3030                 make_bad_inode(journal_inode);
3031                 iput(journal_inode);
3032                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3033                 return NULL;
3034         }
3035
3036         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3037                   journal_inode, journal_inode->i_size);
3038         if (!S_ISREG(journal_inode->i_mode)) {
3039                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3040                 iput(journal_inode);
3041                 return NULL;
3042         }
3043
3044         journal = jbd2_journal_init_inode(journal_inode);
3045         if (!journal) {
3046                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3047                 iput(journal_inode);
3048                 return NULL;
3049         }
3050         journal->j_private = sb;
3051         ext4_init_journal_params(sb, journal);
3052         return journal;
3053 }
3054
3055 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3056                                        dev_t j_dev)
3057 {
3058         struct buffer_head *bh;
3059         journal_t *journal;
3060         ext4_fsblk_t start;
3061         ext4_fsblk_t len;
3062         int hblock, blocksize;
3063         ext4_fsblk_t sb_block;
3064         unsigned long offset;
3065         struct ext4_super_block *es;
3066         struct block_device *bdev;
3067
3068         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3069
3070         bdev = ext4_blkdev_get(j_dev, sb);
3071         if (bdev == NULL)
3072                 return NULL;
3073
3074         if (bd_claim(bdev, sb)) {
3075                 ext4_msg(sb, KERN_ERR,
3076                         "failed to claim external journal device");
3077                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3078                 return NULL;
3079         }
3080
3081         blocksize = sb->s_blocksize;
3082         hblock = bdev_logical_block_size(bdev);
3083         if (blocksize < hblock) {
3084                 ext4_msg(sb, KERN_ERR,
3085                         "blocksize too small for journal device");
3086                 goto out_bdev;
3087         }
3088
3089         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3090         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3091         set_blocksize(bdev, blocksize);
3092         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3093                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3094                        "external journal");
3095                 goto out_bdev;
3096         }
3097
3098         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3099         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3100             !(le32_to_cpu(es->s_feature_incompat) &
3101               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3102                 ext4_msg(sb, KERN_ERR, "external journal has "
3103                                         "bad superblock");
3104                 brelse(bh);
3105                 goto out_bdev;
3106         }
3107
3108         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3109                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3110                 brelse(bh);
3111                 goto out_bdev;
3112         }
3113
3114         len = ext4_blocks_count(es);
3115         start = sb_block + 1;
3116         brelse(bh);     /* we're done with the superblock */
3117
3118         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3119                                         start, len, blocksize);
3120         if (!journal) {
3121                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3122                 goto out_bdev;
3123         }
3124         journal->j_private = sb;
3125         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3126         wait_on_buffer(journal->j_sb_buffer);
3127         if (!buffer_uptodate(journal->j_sb_buffer)) {
3128                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3129                 goto out_journal;
3130         }
3131         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3132                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3133                                         "user (unsupported) - %d",
3134                         be32_to_cpu(journal->j_superblock->s_nr_users));
3135                 goto out_journal;
3136         }
3137         EXT4_SB(sb)->journal_bdev = bdev;
3138         ext4_init_journal_params(sb, journal);
3139         return journal;
3140
3141 out_journal:
3142         jbd2_journal_destroy(journal);
3143 out_bdev:
3144         ext4_blkdev_put(bdev);
3145         return NULL;
3146 }
3147
3148 static int ext4_load_journal(struct super_block *sb,
3149                              struct ext4_super_block *es,
3150                              unsigned long journal_devnum)
3151 {
3152         journal_t *journal;
3153         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3154         dev_t journal_dev;
3155         int err = 0;
3156         int really_read_only;
3157
3158         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3159
3160         if (journal_devnum &&
3161             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3162                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3163                         "numbers have changed");
3164                 journal_dev = new_decode_dev(journal_devnum);
3165         } else
3166                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3167
3168         really_read_only = bdev_read_only(sb->s_bdev);
3169
3170         /*
3171          * Are we loading a blank journal or performing recovery after a
3172          * crash?  For recovery, we need to check in advance whether we
3173          * can get read-write access to the device.
3174          */
3175         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3176                 if (sb->s_flags & MS_RDONLY) {
3177                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3178                                         "required on readonly filesystem");
3179                         if (really_read_only) {
3180                                 ext4_msg(sb, KERN_ERR, "write access "
3181                                         "unavailable, cannot proceed");
3182                                 return -EROFS;
3183                         }
3184                         ext4_msg(sb, KERN_INFO, "write access will "
3185                                "be enabled during recovery");
3186                 }
3187         }
3188
3189         if (journal_inum && journal_dev) {
3190                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3191                        "and inode journals!");
3192                 return -EINVAL;
3193         }
3194
3195         if (journal_inum) {
3196                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3197                         return -EINVAL;
3198         } else {
3199                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3200                         return -EINVAL;
3201         }
3202
3203         if (!(journal->j_flags & JBD2_BARRIER))
3204                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3205
3206         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3207                 err = jbd2_journal_update_format(journal);
3208                 if (err)  {
3209                         ext4_msg(sb, KERN_ERR, "error updating journal");
3210                         jbd2_journal_destroy(journal);
3211                         return err;
3212                 }
3213         }
3214
3215         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3216                 err = jbd2_journal_wipe(journal, !really_read_only);
3217         if (!err)
3218                 err = jbd2_journal_load(journal);
3219
3220         if (err) {
3221                 ext4_msg(sb, KERN_ERR, "error loading journal");
3222                 jbd2_journal_destroy(journal);
3223                 return err;
3224         }
3225
3226         EXT4_SB(sb)->s_journal = journal;
3227         ext4_clear_journal_err(sb, es);
3228
3229         if (journal_devnum &&
3230             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3231                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3232
3233                 /* Make sure we flush the recovery flag to disk. */
3234                 ext4_commit_super(sb, 1);
3235         }
3236
3237         return 0;
3238 }
3239
3240 static int ext4_commit_super(struct super_block *sb, int sync)
3241 {
3242         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3243         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3244         int error = 0;
3245
3246         if (!sbh)
3247                 return error;
3248         if (buffer_write_io_error(sbh)) {
3249                 /*
3250                  * Oh, dear.  A previous attempt to write the
3251                  * superblock failed.  This could happen because the
3252                  * USB device was yanked out.  Or it could happen to
3253                  * be a transient write error and maybe the block will
3254                  * be remapped.  Nothing we can do but to retry the
3255                  * write and hope for the best.
3256                  */
3257                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3258                        "superblock detected");
3259                 clear_buffer_write_io_error(sbh);
3260                 set_buffer_uptodate(sbh);
3261         }
3262         /*
3263          * If the file system is mounted read-only, don't update the
3264          * superblock write time.  This avoids updating the superblock
3265          * write time when we are mounting the root file system
3266          * read/only but we need to replay the journal; at that point,
3267          * for people who are east of GMT and who make their clock
3268          * tick in localtime for Windows bug-for-bug compatibility,
3269          * the clock is set in the future, and this will cause e2fsck
3270          * to complain and force a full file system check.
3271          */
3272         if (!(sb->s_flags & MS_RDONLY))
3273                 es->s_wtime = cpu_to_le32(get_seconds());
3274         es->s_kbytes_written =
3275                 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written + 
3276                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3277                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
3278         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3279                                         &EXT4_SB(sb)->s_freeblocks_counter));
3280         es->s_free_inodes_count = cpu_to_le32(percpu_counter_sum_positive(
3281                                         &EXT4_SB(sb)->s_freeinodes_counter));
3282         sb->s_dirt = 0;
3283         BUFFER_TRACE(sbh, "marking dirty");
3284         mark_buffer_dirty(sbh);
3285         if (sync) {
3286                 error = sync_dirty_buffer(sbh);
3287                 if (error)
3288                         return error;
3289
3290                 error = buffer_write_io_error(sbh);
3291                 if (error) {
3292                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
3293                                "superblock");
3294                         clear_buffer_write_io_error(sbh);
3295                         set_buffer_uptodate(sbh);
3296                 }
3297         }
3298         return error;
3299 }
3300
3301 /*
3302  * Have we just finished recovery?  If so, and if we are mounting (or
3303  * remounting) the filesystem readonly, then we will end up with a
3304  * consistent fs on disk.  Record that fact.
3305  */
3306 static void ext4_mark_recovery_complete(struct super_block *sb,
3307                                         struct ext4_super_block *es)
3308 {
3309         journal_t *journal = EXT4_SB(sb)->s_journal;
3310
3311         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3312                 BUG_ON(journal != NULL);
3313                 return;
3314         }
3315         jbd2_journal_lock_updates(journal);
3316         if (jbd2_journal_flush(journal) < 0)
3317                 goto out;
3318
3319         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
3320             sb->s_flags & MS_RDONLY) {
3321                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3322                 ext4_commit_super(sb, 1);
3323         }
3324
3325 out:
3326         jbd2_journal_unlock_updates(journal);
3327 }
3328
3329 /*
3330  * If we are mounting (or read-write remounting) a filesystem whose journal
3331  * has recorded an error from a previous lifetime, move that error to the
3332  * main filesystem now.
3333  */
3334 static void ext4_clear_journal_err(struct super_block *sb,
3335                                    struct ext4_super_block *es)
3336 {
3337         journal_t *journal;
3338         int j_errno;
3339         const char *errstr;
3340
3341         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3342
3343         journal = EXT4_SB(sb)->s_journal;
3344
3345         /*
3346          * Now check for any error status which may have been recorded in the
3347          * journal by a prior ext4_error() or ext4_abort()
3348          */
3349
3350         j_errno = jbd2_journal_errno(journal);
3351         if (j_errno) {
3352                 char nbuf[16];
3353
3354                 errstr = ext4_decode_error(sb, j_errno, nbuf);
3355                 ext4_warning(sb, __func__, "Filesystem error recorded "
3356                              "from previous mount: %s", errstr);
3357                 ext4_warning(sb, __func__, "Marking fs in need of "
3358                              "filesystem check.");
3359
3360                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
3361                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
3362                 ext4_commit_super(sb, 1);
3363
3364                 jbd2_journal_clear_err(journal);
3365         }
3366 }
3367
3368 /*
3369  * Force the running and committing transactions to commit,
3370  * and wait on the commit.
3371  */
3372 int ext4_force_commit(struct super_block *sb)
3373 {
3374         journal_t *journal;
3375         int ret = 0;
3376
3377         if (sb->s_flags & MS_RDONLY)
3378                 return 0;
3379
3380         journal = EXT4_SB(sb)->s_journal;
3381         if (journal)
3382                 ret = ext4_journal_force_commit(journal);
3383
3384         return ret;
3385 }
3386
3387 static void ext4_write_super(struct super_block *sb)
3388 {
3389         lock_super(sb);
3390         ext4_commit_super(sb, 1);
3391         unlock_super(sb);
3392 }
3393
3394 static int ext4_sync_fs(struct super_block *sb, int wait)
3395 {
3396         int ret = 0;
3397         tid_t target;
3398         struct ext4_sb_info *sbi = EXT4_SB(sb);
3399
3400         trace_ext4_sync_fs(sb, wait);
3401         flush_workqueue(sbi->dio_unwritten_wq);
3402         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
3403                 if (wait)
3404                         jbd2_log_wait_commit(sbi->s_journal, target);
3405         }
3406         return ret;
3407 }
3408
3409 /*
3410  * LVM calls this function before a (read-only) snapshot is created.  This
3411  * gives us a chance to flush the journal completely and mark the fs clean.
3412  */
3413 static int ext4_freeze(struct super_block *sb)
3414 {
3415         int error = 0;
3416         journal_t *journal;
3417
3418         if (sb->s_flags & MS_RDONLY)
3419                 return 0;
3420
3421         journal = EXT4_SB(sb)->s_journal;
3422
3423         /* Now we set up the journal barrier. */
3424         jbd2_journal_lock_updates(journal);
3425
3426         /*
3427          * Don't clear the needs_recovery flag if we failed to flush
3428          * the journal.
3429          */
3430         error = jbd2_journal_flush(journal);
3431         if (error < 0) {
3432         out:
3433                 jbd2_journal_unlock_updates(journal);
3434                 return error;
3435         }
3436
3437         /* Journal blocked and flushed, clear needs_recovery flag. */
3438         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3439         error = ext4_commit_super(sb, 1);
3440         if (error)
3441                 goto out;
3442         return 0;
3443 }
3444
3445 /*
3446  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
3447  * flag here, even though the filesystem is not technically dirty yet.
3448  */
3449 static int ext4_unfreeze(struct super_block *sb)
3450 {
3451         if (sb->s_flags & MS_RDONLY)
3452                 return 0;
3453
3454         lock_super(sb);
3455         /* Reset the needs_recovery flag before the fs is unlocked. */
3456         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3457         ext4_commit_super(sb, 1);
3458         unlock_super(sb);
3459         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3460         return 0;
3461 }
3462
3463 static int ext4_remount(struct super_block *sb, int *flags, char *data)
3464 {
3465         struct ext4_super_block *es;
3466         struct ext4_sb_info *sbi = EXT4_SB(sb);
3467         ext4_fsblk_t n_blocks_count = 0;
3468         unsigned long old_sb_flags;
3469         struct ext4_mount_options old_opts;
3470         ext4_group_t g;
3471         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3472         int err;
3473 #ifdef CONFIG_QUOTA
3474         int i;
3475 #endif
3476
3477         lock_kernel();
3478
3479         /* Store the original options */
3480         lock_super(sb);
3481         old_sb_flags = sb->s_flags;
3482         old_opts.s_mount_opt = sbi->s_mount_opt;
3483         old_opts.s_resuid = sbi->s_resuid;
3484         old_opts.s_resgid = sbi->s_resgid;
3485         old_opts.s_commit_interval = sbi->s_commit_interval;
3486         old_opts.s_min_batch_time = sbi->s_min_batch_time;
3487         old_opts.s_max_batch_time = sbi->s_max_batch_time;
3488 #ifdef CONFIG_QUOTA
3489         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3490         for (i = 0; i < MAXQUOTAS; i++)
3491                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3492 #endif
3493         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
3494                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
3495
3496         /*
3497          * Allow the "check" option to be passed as a remount option.
3498          */
3499         if (!parse_options(data, sb, NULL, &journal_ioprio,
3500                            &n_blocks_count, 1)) {
3501                 err = -EINVAL;
3502                 goto restore_opts;
3503         }
3504
3505         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
3506                 ext4_abort(sb, __func__, "Abort forced by user");
3507
3508         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3509                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
3510
3511         es = sbi->s_es;
3512
3513         if (sbi->s_journal) {
3514                 ext4_init_journal_params(sb, sbi->s_journal);
3515                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3516         }
3517
3518         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3519                 n_blocks_count > ext4_blocks_count(es)) {
3520                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
3521                         err = -EROFS;
3522                         goto restore_opts;
3523                 }
3524
3525                 if (*flags & MS_RDONLY) {
3526                         /*
3527                          * First of all, the unconditional stuff we have to do
3528                          * to disable replay of the journal when we next remount
3529                          */
3530                         sb->s_flags |= MS_RDONLY;
3531
3532                         /*
3533                          * OK, test if we are remounting a valid rw partition
3534                          * readonly, and if so set the rdonly flag and then
3535                          * mark the partition as valid again.
3536                          */
3537                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3538                             (sbi->s_mount_state & EXT4_VALID_FS))
3539                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3540
3541                         if (sbi->s_journal)
3542                                 ext4_mark_recovery_complete(sb, es);
3543                 } else {
3544                         /* Make sure we can mount this feature set readwrite */
3545                         if (!ext4_feature_set_ok(sb, 0)) {
3546                                 err = -EROFS;
3547                                 goto restore_opts;
3548                         }
3549                         /*
3550                          * Make sure the group descriptor checksums
3551                          * are sane.  If they aren't, refuse to remount r/w.
3552                          */
3553                         for (g = 0; g < sbi->s_groups_count; g++) {
3554                                 struct ext4_group_desc *gdp =
3555                                         ext4_get_group_desc(sb, g, NULL);
3556
3557                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3558                                         ext4_msg(sb, KERN_ERR,
3559                "ext4_remount: Checksum for group %u failed (%u!=%u)",
3560                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3561                                                le16_to_cpu(gdp->bg_checksum));
3562                                         err = -EINVAL;
3563                                         goto restore_opts;
3564                                 }
3565                         }
3566
3567                         /*
3568                          * If we have an unprocessed orphan list hanging
3569                          * around from a previously readonly bdev mount,
3570                          * require a full umount/remount for now.
3571                          */
3572                         if (es->s_last_orphan) {
3573                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
3574                                        "remount RDWR because of unprocessed "
3575                                        "orphan inode list.  Please "
3576                                        "umount/remount instead");
3577                                 err = -EINVAL;
3578                                 goto restore_opts;
3579                         }
3580
3581                         /*
3582                          * Mounting a RDONLY partition read-write, so reread
3583                          * and store the current valid flag.  (It may have
3584                          * been changed by e2fsck since we originally mounted
3585                          * the partition.)
3586                          */
3587                         if (sbi->s_journal)
3588                                 ext4_clear_journal_err(sb, es);
3589                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3590                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3591                                 goto restore_opts;
3592                         if (!ext4_setup_super(sb, es, 0))
3593                                 sb->s_flags &= ~MS_RDONLY;
3594                 }
3595         }
3596         ext4_setup_system_zone(sb);
3597         if (sbi->s_journal == NULL)
3598                 ext4_commit_super(sb, 1);
3599
3600 #ifdef CONFIG_QUOTA
3601         /* Release old quota file names */
3602         for (i = 0; i < MAXQUOTAS; i++)
3603                 if (old_opts.s_qf_names[i] &&
3604                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3605                         kfree(old_opts.s_qf_names[i]);
3606 #endif
3607         unlock_super(sb);
3608         unlock_kernel();
3609         return 0;
3610
3611 restore_opts:
3612         sb->s_flags = old_sb_flags;
3613         sbi->s_mount_opt = old_opts.s_mount_opt;
3614         sbi->s_resuid = old_opts.s_resuid;
3615         sbi->s_resgid = old_opts.s_resgid;
3616         sbi->s_commit_interval = old_opts.s_commit_interval;
3617         sbi->s_min_batch_time = old_opts.s_min_batch_time;
3618         sbi->s_max_batch_time = old_opts.s_max_batch_time;
3619 #ifdef CONFIG_QUOTA
3620         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3621         for (i = 0; i < MAXQUOTAS; i++) {
3622                 if (sbi->s_qf_names[i] &&
3623                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3624                         kfree(sbi->s_qf_names[i]);
3625                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3626         }
3627 #endif
3628         unlock_super(sb);
3629         unlock_kernel();
3630         return err;
3631 }
3632
3633 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3634 {
3635         struct super_block *sb = dentry->d_sb;
3636         struct ext4_sb_info *sbi = EXT4_SB(sb);
3637         struct ext4_super_block *es = sbi->s_es;
3638         u64 fsid;
3639
3640         if (test_opt(sb, MINIX_DF)) {
3641                 sbi->s_overhead_last = 0;
3642         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3643                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3644                 ext4_fsblk_t overhead = 0;
3645
3646                 /*
3647                  * Compute the overhead (FS structures).  This is constant
3648                  * for a given filesystem unless the number of block groups
3649                  * changes so we cache the previous value until it does.
3650                  */
3651
3652                 /*
3653                  * All of the blocks before first_data_block are
3654                  * overhead
3655                  */
3656                 overhead = le32_to_cpu(es->s_first_data_block);
3657
3658                 /*
3659                  * Add the overhead attributed to the superblock and
3660                  * block group descriptors.  If the sparse superblocks
3661                  * feature is turned on, then not all groups have this.
3662                  */
3663                 for (i = 0; i < ngroups; i++) {
3664                         overhead += ext4_bg_has_super(sb, i) +
3665                                 ext4_bg_num_gdb(sb, i);
3666                         cond_resched();
3667                 }
3668
3669                 /*
3670                  * Every block group has an inode bitmap, a block
3671                  * bitmap, and an inode table.
3672                  */
3673                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3674                 sbi->s_overhead_last = overhead;
3675                 smp_wmb();
3676                 sbi->s_blocks_last = ext4_blocks_count(es);
3677         }
3678
3679         buf->f_type = EXT4_SUPER_MAGIC;
3680         buf->f_bsize = sb->s_blocksize;
3681         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3682         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3683                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3684         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3685         if (buf->f_bfree < ext4_r_blocks_count(es))
3686                 buf->f_bavail = 0;
3687         buf->f_files = le32_to_cpu(es->s_inodes_count);
3688         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3689         buf->f_namelen = EXT4_NAME_LEN;
3690         fsid = le64_to_cpup((void *)es->s_uuid) ^
3691                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3692         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3693         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3694
3695         return 0;
3696 }
3697
3698 /* Helper function for writing quotas on sync - we need to start transaction
3699  * before quota file is locked for write. Otherwise the are possible deadlocks:
3700  * Process 1                         Process 2
3701  * ext4_create()                     quota_sync()
3702  *   jbd2_journal_start()                  write_dquot()
3703  *   vfs_dq_init()                         down(dqio_mutex)
3704  *     down(dqio_mutex)                    jbd2_journal_start()
3705  *
3706  */
3707
3708 #ifdef CONFIG_QUOTA
3709
3710 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3711 {
3712         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3713 }
3714
3715 static int ext4_write_dquot(struct dquot *dquot)
3716 {
3717         int ret, err;
3718         handle_t *handle;
3719         struct inode *inode;
3720
3721         inode = dquot_to_inode(dquot);
3722         handle = ext4_journal_start(inode,
3723                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3724         if (IS_ERR(handle))
3725                 return PTR_ERR(handle);
3726         ret = dquot_commit(dquot);
3727         err = ext4_journal_stop(handle);
3728         if (!ret)
3729                 ret = err;
3730         return ret;
3731 }
3732
3733 static int ext4_acquire_dquot(struct dquot *dquot)
3734 {
3735         int ret, err;
3736         handle_t *handle;
3737
3738         handle = ext4_journal_start(dquot_to_inode(dquot),
3739                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3740         if (IS_ERR(handle))
3741                 return PTR_ERR(handle);
3742         ret = dquot_acquire(dquot);
3743         err = ext4_journal_stop(handle);
3744         if (!ret)
3745                 ret = err;
3746         return ret;
3747 }
3748
3749 static int ext4_release_dquot(struct dquot *dquot)
3750 {
3751         int ret, err;
3752         handle_t *handle;
3753
3754         handle = ext4_journal_start(dquot_to_inode(dquot),
3755                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3756         if (IS_ERR(handle)) {
3757                 /* Release dquot anyway to avoid endless cycle in dqput() */
3758                 dquot_release(dquot);
3759                 return PTR_ERR(handle);
3760         }
3761         ret = dquot_release(dquot);
3762         err = ext4_journal_stop(handle);
3763         if (!ret)
3764                 ret = err;
3765         return ret;
3766 }
3767
3768 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3769 {
3770         /* Are we journaling quotas? */
3771         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3772             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3773                 dquot_mark_dquot_dirty(dquot);
3774                 return ext4_write_dquot(dquot);
3775         } else {
3776                 return dquot_mark_dquot_dirty(dquot);
3777         }
3778 }
3779
3780 static int ext4_write_info(struct super_block *sb, int type)
3781 {
3782         int ret, err;
3783         handle_t *handle;
3784
3785         /* Data block + inode block */
3786         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3787         if (IS_ERR(handle))
3788                 return PTR_ERR(handle);
3789         ret = dquot_commit_info(sb, type);
3790         err = ext4_journal_stop(handle);
3791         if (!ret)
3792                 ret = err;
3793         return ret;
3794 }
3795
3796 /*
3797  * Turn on quotas during mount time - we need to find
3798  * the quota file and such...
3799  */
3800 static int ext4_quota_on_mount(struct super_block *sb, int type)
3801 {
3802         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3803                                   EXT4_SB(sb)->s_jquota_fmt, type);
3804 }
3805
3806 /*
3807  * Standard function to be called on quota_on
3808  */
3809 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3810                          char *name, int remount)
3811 {
3812         int err;
3813         struct path path;
3814
3815         if (!test_opt(sb, QUOTA))
3816                 return -EINVAL;
3817         /* When remounting, no checks are needed and in fact, name is NULL */
3818         if (remount)
3819                 return vfs_quota_on(sb, type, format_id, name, remount);
3820
3821         err = kern_path(name, LOOKUP_FOLLOW, &path);
3822         if (err)
3823                 return err;
3824
3825         /* Quotafile not on the same filesystem? */
3826         if (path.mnt->mnt_sb != sb) {
3827                 path_put(&path);
3828                 return -EXDEV;
3829         }
3830         /* Journaling quota? */
3831         if (EXT4_SB(sb)->s_qf_names[type]) {
3832                 /* Quotafile not in fs root? */
3833                 if (path.dentry->d_parent != sb->s_root)
3834                         ext4_msg(sb, KERN_WARNING,
3835                                 "Quota file not on filesystem root. "
3836                                 "Journaled quota will not work");
3837         }
3838
3839         /*
3840          * When we journal data on quota file, we have to flush journal to see
3841          * all updates to the file when we bypass pagecache...
3842          */
3843         if (EXT4_SB(sb)->s_journal &&
3844             ext4_should_journal_data(path.dentry->d_inode)) {
3845                 /*
3846                  * We don't need to lock updates but journal_flush() could
3847                  * otherwise be livelocked...
3848                  */
3849                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3850                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3851                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3852                 if (err) {
3853                         path_put(&path);
3854                         return err;
3855                 }
3856         }
3857
3858         err = vfs_quota_on_path(sb, type, format_id, &path);
3859         path_put(&path);
3860         return err;
3861 }
3862
3863 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3864  * acquiring the locks... As quota files are never truncated and quota code
3865  * itself serializes the operations (and noone else should touch the files)
3866  * we don't have to be afraid of races */
3867 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3868                                size_t len, loff_t off)
3869 {
3870         struct inode *inode = sb_dqopt(sb)->files[type];
3871         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3872         int err = 0;
3873         int offset = off & (sb->s_blocksize - 1);
3874         int tocopy;
3875         size_t toread;
3876         struct buffer_head *bh;
3877         loff_t i_size = i_size_read(inode);
3878
3879         if (off > i_size)
3880                 return 0;
3881         if (off+len > i_size)
3882                 len = i_size-off;
3883         toread = len;
3884         while (toread > 0) {
3885                 tocopy = sb->s_blocksize - offset < toread ?
3886                                 sb->s_blocksize - offset : toread;
3887                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3888                 if (err)
3889                         return err;
3890                 if (!bh)        /* A hole? */
3891                         memset(data, 0, tocopy);
3892                 else
3893                         memcpy(data, bh->b_data+offset, tocopy);
3894                 brelse(bh);
3895                 offset = 0;
3896                 toread -= tocopy;
3897                 data += tocopy;
3898                 blk++;
3899         }
3900         return len;
3901 }
3902
3903 /* Write to quotafile (we know the transaction is already started and has
3904  * enough credits) */
3905 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3906                                 const char *data, size_t len, loff_t off)
3907 {
3908         struct inode *inode = sb_dqopt(sb)->files[type];
3909         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3910         int err = 0;
3911         int offset = off & (sb->s_blocksize - 1);
3912         int tocopy;
3913         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3914         size_t towrite = len;
3915         struct buffer_head *bh;
3916         handle_t *handle = journal_current_handle();
3917
3918         if (EXT4_SB(sb)->s_journal && !handle) {
3919                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
3920                         " cancelled because transaction is not started",
3921                         (unsigned long long)off, (unsigned long long)len);
3922                 return -EIO;
3923         }
3924         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3925         while (towrite > 0) {
3926                 tocopy = sb->s_blocksize - offset < towrite ?
3927                                 sb->s_blocksize - offset : towrite;
3928                 bh = ext4_bread(handle, inode, blk, 1, &err);
3929                 if (!bh)
3930                         goto out;
3931                 if (journal_quota) {
3932                         err = ext4_journal_get_write_access(handle, bh);
3933                         if (err) {
3934                                 brelse(bh);
3935                                 goto out;
3936                         }
3937                 }
3938                 lock_buffer(bh);
3939                 memcpy(bh->b_data+offset, data, tocopy);
3940                 flush_dcache_page(bh->b_page);
3941                 unlock_buffer(bh);
3942                 if (journal_quota)
3943                         err = ext4_handle_dirty_metadata(handle, NULL, bh);
3944                 else {
3945                         /* Always do at least ordered writes for quotas */
3946                         err = ext4_jbd2_file_inode(handle, inode);
3947                         mark_buffer_dirty(bh);
3948                 }
3949                 brelse(bh);
3950                 if (err)
3951                         goto out;
3952                 offset = 0;
3953                 towrite -= tocopy;
3954                 data += tocopy;
3955                 blk++;
3956         }
3957 out:
3958         if (len == towrite) {
3959                 mutex_unlock(&inode->i_mutex);
3960                 return err;
3961         }
3962         if (inode->i_size < off+len-towrite) {
3963                 i_size_write(inode, off+len-towrite);
3964                 EXT4_I(inode)->i_disksize = inode->i_size;
3965         }
3966         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3967         ext4_mark_inode_dirty(handle, inode);
3968         mutex_unlock(&inode->i_mutex);
3969         return len - towrite;
3970 }
3971
3972 #endif
3973
3974 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
3975                        const char *dev_name, void *data, struct vfsmount *mnt)
3976 {
3977         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
3978 }
3979
3980 #if !defined(CONTIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
3981 static struct file_system_type ext2_fs_type = {
3982         .owner          = THIS_MODULE,
3983         .name           = "ext2",
3984         .get_sb         = ext4_get_sb,
3985         .kill_sb        = kill_block_super,
3986         .fs_flags       = FS_REQUIRES_DEV,
3987 };
3988
3989 static inline void register_as_ext2(void)
3990 {
3991         int err = register_filesystem(&ext2_fs_type);
3992         if (err)
3993                 printk(KERN_WARNING
3994                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
3995 }
3996
3997 static inline void unregister_as_ext2(void)
3998 {
3999         unregister_filesystem(&ext2_fs_type);
4000 }
4001 MODULE_ALIAS("ext2");
4002 #else
4003 static inline void register_as_ext2(void) { }
4004 static inline void unregister_as_ext2(void) { }
4005 #endif
4006
4007 #if !defined(CONTIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4008 static struct file_system_type ext3_fs_type = {
4009         .owner          = THIS_MODULE,
4010         .name           = "ext3",
4011         .get_sb         = ext4_get_sb,
4012         .kill_sb        = kill_block_super,
4013         .fs_flags       = FS_REQUIRES_DEV,
4014 };
4015
4016 static inline void register_as_ext3(void)
4017 {
4018         int err = register_filesystem(&ext3_fs_type);
4019         if (err)
4020                 printk(KERN_WARNING
4021                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
4022 }
4023
4024 static inline void unregister_as_ext3(void)
4025 {
4026         unregister_filesystem(&ext3_fs_type);
4027 }
4028 MODULE_ALIAS("ext3");
4029 #else
4030 static inline void register_as_ext3(void) { }
4031 static inline void unregister_as_ext3(void) { }
4032 #endif
4033
4034 static struct file_system_type ext4_fs_type = {
4035         .owner          = THIS_MODULE,
4036         .name           = "ext4",
4037         .get_sb         = ext4_get_sb,
4038         .kill_sb        = kill_block_super,
4039         .fs_flags       = FS_REQUIRES_DEV,
4040 };
4041
4042 static int __init init_ext4_fs(void)
4043 {
4044         int err;
4045
4046         err = init_ext4_system_zone();
4047         if (err)
4048                 return err;
4049         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
4050         if (!ext4_kset)
4051                 goto out4;
4052         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
4053         err = init_ext4_mballoc();
4054         if (err)
4055                 goto out3;
4056
4057         err = init_ext4_xattr();
4058         if (err)
4059                 goto out2;
4060         err = init_inodecache();
4061         if (err)
4062                 goto out1;
4063         register_as_ext2();
4064         register_as_ext3();
4065         err = register_filesystem(&ext4_fs_type);
4066         if (err)
4067                 goto out;
4068         return 0;
4069 out:
4070         unregister_as_ext2();
4071         unregister_as_ext3();
4072         destroy_inodecache();
4073 out1:
4074         exit_ext4_xattr();
4075 out2:
4076         exit_ext4_mballoc();
4077 out3:
4078         remove_proc_entry("fs/ext4", NULL);
4079         kset_unregister(ext4_kset);
4080 out4:
4081         exit_ext4_system_zone();
4082         return err;
4083 }
4084
4085 static void __exit exit_ext4_fs(void)
4086 {
4087         unregister_as_ext2();
4088         unregister_as_ext3();
4089         unregister_filesystem(&ext4_fs_type);
4090         destroy_inodecache();
4091         exit_ext4_xattr();
4092         exit_ext4_mballoc();
4093         remove_proc_entry("fs/ext4", NULL);
4094         kset_unregister(ext4_kset);
4095         exit_ext4_system_zone();
4096 }
4097
4098 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4099 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4100 MODULE_LICENSE("GPL");
4101 module_init(init_ext4_fs)
4102 module_exit(exit_ext4_fs)