ext4: add module aliases for ext2 and ext3
[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_delalloc_reserved_flag = 0;
706         spin_lock_init(&(ei->i_block_reservation_lock));
707 #ifdef CONFIG_QUOTA
708         ei->i_reserved_quota = 0;
709 #endif
710         INIT_LIST_HEAD(&ei->i_aio_dio_complete_list);
711         ei->cur_aio_dio = NULL;
712         ei->i_sync_tid = 0;
713         ei->i_datasync_tid = 0;
714
715         return &ei->vfs_inode;
716 }
717
718 static void ext4_destroy_inode(struct inode *inode)
719 {
720         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
721                 ext4_msg(inode->i_sb, KERN_ERR,
722                          "Inode %lu (%p): orphan list check failed!",
723                          inode->i_ino, EXT4_I(inode));
724                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
725                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
726                                 true);
727                 dump_stack();
728         }
729         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
730 }
731
732 static void init_once(void *foo)
733 {
734         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
735
736         INIT_LIST_HEAD(&ei->i_orphan);
737 #ifdef CONFIG_EXT4_FS_XATTR
738         init_rwsem(&ei->xattr_sem);
739 #endif
740         init_rwsem(&ei->i_data_sem);
741         inode_init_once(&ei->vfs_inode);
742 }
743
744 static int init_inodecache(void)
745 {
746         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
747                                              sizeof(struct ext4_inode_info),
748                                              0, (SLAB_RECLAIM_ACCOUNT|
749                                                 SLAB_MEM_SPREAD),
750                                              init_once);
751         if (ext4_inode_cachep == NULL)
752                 return -ENOMEM;
753         return 0;
754 }
755
756 static void destroy_inodecache(void)
757 {
758         kmem_cache_destroy(ext4_inode_cachep);
759 }
760
761 static void ext4_clear_inode(struct inode *inode)
762 {
763         ext4_discard_preallocations(inode);
764         if (EXT4_JOURNAL(inode))
765                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
766                                        &EXT4_I(inode)->jinode);
767 }
768
769 static inline void ext4_show_quota_options(struct seq_file *seq,
770                                            struct super_block *sb)
771 {
772 #if defined(CONFIG_QUOTA)
773         struct ext4_sb_info *sbi = EXT4_SB(sb);
774
775         if (sbi->s_jquota_fmt) {
776                 char *fmtname = "";
777
778                 switch (sbi->s_jquota_fmt) {
779                 case QFMT_VFS_OLD:
780                         fmtname = "vfsold";
781                         break;
782                 case QFMT_VFS_V0:
783                         fmtname = "vfsv0";
784                         break;
785                 case QFMT_VFS_V1:
786                         fmtname = "vfsv1";
787                         break;
788                 }
789                 seq_printf(seq, ",jqfmt=%s", fmtname);
790         }
791
792         if (sbi->s_qf_names[USRQUOTA])
793                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
794
795         if (sbi->s_qf_names[GRPQUOTA])
796                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
797
798         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
799                 seq_puts(seq, ",usrquota");
800
801         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
802                 seq_puts(seq, ",grpquota");
803 #endif
804 }
805
806 /*
807  * Show an option if
808  *  - it's set to a non-default value OR
809  *  - if the per-sb default is different from the global default
810  */
811 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
812 {
813         int def_errors;
814         unsigned long def_mount_opts;
815         struct super_block *sb = vfs->mnt_sb;
816         struct ext4_sb_info *sbi = EXT4_SB(sb);
817         struct ext4_super_block *es = sbi->s_es;
818
819         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
820         def_errors     = le16_to_cpu(es->s_errors);
821
822         if (sbi->s_sb_block != 1)
823                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
824         if (test_opt(sb, MINIX_DF))
825                 seq_puts(seq, ",minixdf");
826         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
827                 seq_puts(seq, ",grpid");
828         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
829                 seq_puts(seq, ",nogrpid");
830         if (sbi->s_resuid != EXT4_DEF_RESUID ||
831             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
832                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
833         }
834         if (sbi->s_resgid != EXT4_DEF_RESGID ||
835             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
836                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
837         }
838         if (test_opt(sb, ERRORS_RO)) {
839                 if (def_errors == EXT4_ERRORS_PANIC ||
840                     def_errors == EXT4_ERRORS_CONTINUE) {
841                         seq_puts(seq, ",errors=remount-ro");
842                 }
843         }
844         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
845                 seq_puts(seq, ",errors=continue");
846         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
847                 seq_puts(seq, ",errors=panic");
848         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
849                 seq_puts(seq, ",nouid32");
850         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
851                 seq_puts(seq, ",debug");
852         if (test_opt(sb, OLDALLOC))
853                 seq_puts(seq, ",oldalloc");
854 #ifdef CONFIG_EXT4_FS_XATTR
855         if (test_opt(sb, XATTR_USER) &&
856                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
857                 seq_puts(seq, ",user_xattr");
858         if (!test_opt(sb, XATTR_USER) &&
859             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
860                 seq_puts(seq, ",nouser_xattr");
861         }
862 #endif
863 #ifdef CONFIG_EXT4_FS_POSIX_ACL
864         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
865                 seq_puts(seq, ",acl");
866         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
867                 seq_puts(seq, ",noacl");
868 #endif
869         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
870                 seq_printf(seq, ",commit=%u",
871                            (unsigned) (sbi->s_commit_interval / HZ));
872         }
873         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
874                 seq_printf(seq, ",min_batch_time=%u",
875                            (unsigned) sbi->s_min_batch_time);
876         }
877         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
878                 seq_printf(seq, ",max_batch_time=%u",
879                            (unsigned) sbi->s_min_batch_time);
880         }
881
882         /*
883          * We're changing the default of barrier mount option, so
884          * let's always display its mount state so it's clear what its
885          * status is.
886          */
887         seq_puts(seq, ",barrier=");
888         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
889         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
890                 seq_puts(seq, ",journal_async_commit");
891         if (test_opt(sb, NOBH))
892                 seq_puts(seq, ",nobh");
893         if (test_opt(sb, I_VERSION))
894                 seq_puts(seq, ",i_version");
895         if (!test_opt(sb, DELALLOC))
896                 seq_puts(seq, ",nodelalloc");
897
898
899         if (sbi->s_stripe)
900                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
901         /*
902          * journal mode get enabled in different ways
903          * So just print the value even if we didn't specify it
904          */
905         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
906                 seq_puts(seq, ",data=journal");
907         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
908                 seq_puts(seq, ",data=ordered");
909         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
910                 seq_puts(seq, ",data=writeback");
911
912         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
913                 seq_printf(seq, ",inode_readahead_blks=%u",
914                            sbi->s_inode_readahead_blks);
915
916         if (test_opt(sb, DATA_ERR_ABORT))
917                 seq_puts(seq, ",data_err=abort");
918
919         if (test_opt(sb, NO_AUTO_DA_ALLOC))
920                 seq_puts(seq, ",noauto_da_alloc");
921
922         if (test_opt(sb, DISCARD))
923                 seq_puts(seq, ",discard");
924
925         if (test_opt(sb, NOLOAD))
926                 seq_puts(seq, ",norecovery");
927
928         ext4_show_quota_options(seq, sb);
929
930         return 0;
931 }
932
933 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
934                                         u64 ino, u32 generation)
935 {
936         struct inode *inode;
937
938         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
939                 return ERR_PTR(-ESTALE);
940         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
941                 return ERR_PTR(-ESTALE);
942
943         /* iget isn't really right if the inode is currently unallocated!!
944          *
945          * ext4_read_inode will return a bad_inode if the inode had been
946          * deleted, so we should be safe.
947          *
948          * Currently we don't know the generation for parent directory, so
949          * a generation of 0 means "accept any"
950          */
951         inode = ext4_iget(sb, ino);
952         if (IS_ERR(inode))
953                 return ERR_CAST(inode);
954         if (generation && inode->i_generation != generation) {
955                 iput(inode);
956                 return ERR_PTR(-ESTALE);
957         }
958
959         return inode;
960 }
961
962 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
963                                         int fh_len, int fh_type)
964 {
965         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
966                                     ext4_nfs_get_inode);
967 }
968
969 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
970                                         int fh_len, int fh_type)
971 {
972         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
973                                     ext4_nfs_get_inode);
974 }
975
976 /*
977  * Try to release metadata pages (indirect blocks, directories) which are
978  * mapped via the block device.  Since these pages could have journal heads
979  * which would prevent try_to_free_buffers() from freeing them, we must use
980  * jbd2 layer's try_to_free_buffers() function to release them.
981  */
982 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
983                                  gfp_t wait)
984 {
985         journal_t *journal = EXT4_SB(sb)->s_journal;
986
987         WARN_ON(PageChecked(page));
988         if (!page_has_buffers(page))
989                 return 0;
990         if (journal)
991                 return jbd2_journal_try_to_free_buffers(journal, page,
992                                                         wait & ~__GFP_WAIT);
993         return try_to_free_buffers(page);
994 }
995
996 #ifdef CONFIG_QUOTA
997 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
998 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
999
1000 static int ext4_write_dquot(struct dquot *dquot);
1001 static int ext4_acquire_dquot(struct dquot *dquot);
1002 static int ext4_release_dquot(struct dquot *dquot);
1003 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1004 static int ext4_write_info(struct super_block *sb, int type);
1005 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1006                                 char *path, int remount);
1007 static int ext4_quota_on_mount(struct super_block *sb, int type);
1008 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1009                                size_t len, loff_t off);
1010 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1011                                 const char *data, size_t len, loff_t off);
1012
1013 static const struct dquot_operations ext4_quota_operations = {
1014         .initialize     = dquot_initialize,
1015         .drop           = dquot_drop,
1016         .alloc_space    = dquot_alloc_space,
1017         .reserve_space  = dquot_reserve_space,
1018         .claim_space    = dquot_claim_space,
1019         .release_rsv    = dquot_release_reserved_space,
1020 #ifdef CONFIG_QUOTA
1021         .get_reserved_space = ext4_get_reserved_space,
1022 #endif
1023         .alloc_inode    = dquot_alloc_inode,
1024         .free_space     = dquot_free_space,
1025         .free_inode     = dquot_free_inode,
1026         .transfer       = dquot_transfer,
1027         .write_dquot    = ext4_write_dquot,
1028         .acquire_dquot  = ext4_acquire_dquot,
1029         .release_dquot  = ext4_release_dquot,
1030         .mark_dirty     = ext4_mark_dquot_dirty,
1031         .write_info     = ext4_write_info,
1032         .alloc_dquot    = dquot_alloc,
1033         .destroy_dquot  = dquot_destroy,
1034 };
1035
1036 static const struct quotactl_ops ext4_qctl_operations = {
1037         .quota_on       = ext4_quota_on,
1038         .quota_off      = vfs_quota_off,
1039         .quota_sync     = vfs_quota_sync,
1040         .get_info       = vfs_get_dqinfo,
1041         .set_info       = vfs_set_dqinfo,
1042         .get_dqblk      = vfs_get_dqblk,
1043         .set_dqblk      = vfs_set_dqblk
1044 };
1045 #endif
1046
1047 static const struct super_operations ext4_sops = {
1048         .alloc_inode    = ext4_alloc_inode,
1049         .destroy_inode  = ext4_destroy_inode,
1050         .write_inode    = ext4_write_inode,
1051         .dirty_inode    = ext4_dirty_inode,
1052         .delete_inode   = ext4_delete_inode,
1053         .put_super      = ext4_put_super,
1054         .sync_fs        = ext4_sync_fs,
1055         .freeze_fs      = ext4_freeze,
1056         .unfreeze_fs    = ext4_unfreeze,
1057         .statfs         = ext4_statfs,
1058         .remount_fs     = ext4_remount,
1059         .clear_inode    = ext4_clear_inode,
1060         .show_options   = ext4_show_options,
1061 #ifdef CONFIG_QUOTA
1062         .quota_read     = ext4_quota_read,
1063         .quota_write    = ext4_quota_write,
1064 #endif
1065         .bdev_try_to_free_page = bdev_try_to_free_page,
1066 };
1067
1068 static const struct super_operations ext4_nojournal_sops = {
1069         .alloc_inode    = ext4_alloc_inode,
1070         .destroy_inode  = ext4_destroy_inode,
1071         .write_inode    = ext4_write_inode,
1072         .dirty_inode    = ext4_dirty_inode,
1073         .delete_inode   = ext4_delete_inode,
1074         .write_super    = ext4_write_super,
1075         .put_super      = ext4_put_super,
1076         .statfs         = ext4_statfs,
1077         .remount_fs     = ext4_remount,
1078         .clear_inode    = ext4_clear_inode,
1079         .show_options   = ext4_show_options,
1080 #ifdef CONFIG_QUOTA
1081         .quota_read     = ext4_quota_read,
1082         .quota_write    = ext4_quota_write,
1083 #endif
1084         .bdev_try_to_free_page = bdev_try_to_free_page,
1085 };
1086
1087 static const struct export_operations ext4_export_ops = {
1088         .fh_to_dentry = ext4_fh_to_dentry,
1089         .fh_to_parent = ext4_fh_to_parent,
1090         .get_parent = ext4_get_parent,
1091 };
1092
1093 enum {
1094         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1095         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1096         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1097         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1098         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1099         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1100         Opt_journal_update, Opt_journal_dev,
1101         Opt_journal_checksum, Opt_journal_async_commit,
1102         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1103         Opt_data_err_abort, Opt_data_err_ignore,
1104         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1105         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1106         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1107         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1108         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1109         Opt_block_validity, Opt_noblock_validity,
1110         Opt_inode_readahead_blks, Opt_journal_ioprio,
1111         Opt_discard, Opt_nodiscard,
1112 };
1113
1114 static const match_table_t tokens = {
1115         {Opt_bsd_df, "bsddf"},
1116         {Opt_minix_df, "minixdf"},
1117         {Opt_grpid, "grpid"},
1118         {Opt_grpid, "bsdgroups"},
1119         {Opt_nogrpid, "nogrpid"},
1120         {Opt_nogrpid, "sysvgroups"},
1121         {Opt_resgid, "resgid=%u"},
1122         {Opt_resuid, "resuid=%u"},
1123         {Opt_sb, "sb=%u"},
1124         {Opt_err_cont, "errors=continue"},
1125         {Opt_err_panic, "errors=panic"},
1126         {Opt_err_ro, "errors=remount-ro"},
1127         {Opt_nouid32, "nouid32"},
1128         {Opt_debug, "debug"},
1129         {Opt_oldalloc, "oldalloc"},
1130         {Opt_orlov, "orlov"},
1131         {Opt_user_xattr, "user_xattr"},
1132         {Opt_nouser_xattr, "nouser_xattr"},
1133         {Opt_acl, "acl"},
1134         {Opt_noacl, "noacl"},
1135         {Opt_noload, "noload"},
1136         {Opt_noload, "norecovery"},
1137         {Opt_nobh, "nobh"},
1138         {Opt_bh, "bh"},
1139         {Opt_commit, "commit=%u"},
1140         {Opt_min_batch_time, "min_batch_time=%u"},
1141         {Opt_max_batch_time, "max_batch_time=%u"},
1142         {Opt_journal_update, "journal=update"},
1143         {Opt_journal_dev, "journal_dev=%u"},
1144         {Opt_journal_checksum, "journal_checksum"},
1145         {Opt_journal_async_commit, "journal_async_commit"},
1146         {Opt_abort, "abort"},
1147         {Opt_data_journal, "data=journal"},
1148         {Opt_data_ordered, "data=ordered"},
1149         {Opt_data_writeback, "data=writeback"},
1150         {Opt_data_err_abort, "data_err=abort"},
1151         {Opt_data_err_ignore, "data_err=ignore"},
1152         {Opt_offusrjquota, "usrjquota="},
1153         {Opt_usrjquota, "usrjquota=%s"},
1154         {Opt_offgrpjquota, "grpjquota="},
1155         {Opt_grpjquota, "grpjquota=%s"},
1156         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1157         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1158         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1159         {Opt_grpquota, "grpquota"},
1160         {Opt_noquota, "noquota"},
1161         {Opt_quota, "quota"},
1162         {Opt_usrquota, "usrquota"},
1163         {Opt_barrier, "barrier=%u"},
1164         {Opt_barrier, "barrier"},
1165         {Opt_nobarrier, "nobarrier"},
1166         {Opt_i_version, "i_version"},
1167         {Opt_stripe, "stripe=%u"},
1168         {Opt_resize, "resize"},
1169         {Opt_delalloc, "delalloc"},
1170         {Opt_nodelalloc, "nodelalloc"},
1171         {Opt_block_validity, "block_validity"},
1172         {Opt_noblock_validity, "noblock_validity"},
1173         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1174         {Opt_journal_ioprio, "journal_ioprio=%u"},
1175         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1176         {Opt_auto_da_alloc, "auto_da_alloc"},
1177         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1178         {Opt_discard, "discard"},
1179         {Opt_nodiscard, "nodiscard"},
1180         {Opt_err, NULL},
1181 };
1182
1183 static ext4_fsblk_t get_sb_block(void **data)
1184 {
1185         ext4_fsblk_t    sb_block;
1186         char            *options = (char *) *data;
1187
1188         if (!options || strncmp(options, "sb=", 3) != 0)
1189                 return 1;       /* Default location */
1190
1191         options += 3;
1192         /* TODO: use simple_strtoll with >32bit ext4 */
1193         sb_block = simple_strtoul(options, &options, 0);
1194         if (*options && *options != ',') {
1195                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1196                        (char *) *data);
1197                 return 1;
1198         }
1199         if (*options == ',')
1200                 options++;
1201         *data = (void *) options;
1202
1203         return sb_block;
1204 }
1205
1206 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1207
1208 static int parse_options(char *options, struct super_block *sb,
1209                          unsigned long *journal_devnum,
1210                          unsigned int *journal_ioprio,
1211                          ext4_fsblk_t *n_blocks_count, int is_remount)
1212 {
1213         struct ext4_sb_info *sbi = EXT4_SB(sb);
1214         char *p;
1215         substring_t args[MAX_OPT_ARGS];
1216         int data_opt = 0;
1217         int option;
1218 #ifdef CONFIG_QUOTA
1219         int qtype, qfmt;
1220         char *qname;
1221 #endif
1222
1223         if (!options)
1224                 return 1;
1225
1226         while ((p = strsep(&options, ",")) != NULL) {
1227                 int token;
1228                 if (!*p)
1229                         continue;
1230
1231                 token = match_token(p, tokens, args);
1232                 switch (token) {
1233                 case Opt_bsd_df:
1234                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1235                         break;
1236                 case Opt_minix_df:
1237                         set_opt(sbi->s_mount_opt, MINIX_DF);
1238                         break;
1239                 case Opt_grpid:
1240                         set_opt(sbi->s_mount_opt, GRPID);
1241                         break;
1242                 case Opt_nogrpid:
1243                         clear_opt(sbi->s_mount_opt, GRPID);
1244                         break;
1245                 case Opt_resuid:
1246                         if (match_int(&args[0], &option))
1247                                 return 0;
1248                         sbi->s_resuid = option;
1249                         break;
1250                 case Opt_resgid:
1251                         if (match_int(&args[0], &option))
1252                                 return 0;
1253                         sbi->s_resgid = option;
1254                         break;
1255                 case Opt_sb:
1256                         /* handled by get_sb_block() instead of here */
1257                         /* *sb_block = match_int(&args[0]); */
1258                         break;
1259                 case Opt_err_panic:
1260                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1261                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1262                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1263                         break;
1264                 case Opt_err_ro:
1265                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1266                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1267                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1268                         break;
1269                 case Opt_err_cont:
1270                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1271                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1272                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1273                         break;
1274                 case Opt_nouid32:
1275                         set_opt(sbi->s_mount_opt, NO_UID32);
1276                         break;
1277                 case Opt_debug:
1278                         set_opt(sbi->s_mount_opt, DEBUG);
1279                         break;
1280                 case Opt_oldalloc:
1281                         set_opt(sbi->s_mount_opt, OLDALLOC);
1282                         break;
1283                 case Opt_orlov:
1284                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1285                         break;
1286 #ifdef CONFIG_EXT4_FS_XATTR
1287                 case Opt_user_xattr:
1288                         set_opt(sbi->s_mount_opt, XATTR_USER);
1289                         break;
1290                 case Opt_nouser_xattr:
1291                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1292                         break;
1293 #else
1294                 case Opt_user_xattr:
1295                 case Opt_nouser_xattr:
1296                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1297                         break;
1298 #endif
1299 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1300                 case Opt_acl:
1301                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1302                         break;
1303                 case Opt_noacl:
1304                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1305                         break;
1306 #else
1307                 case Opt_acl:
1308                 case Opt_noacl:
1309                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1310                         break;
1311 #endif
1312                 case Opt_journal_update:
1313                         /* @@@ FIXME */
1314                         /* Eventually we will want to be able to create
1315                            a journal file here.  For now, only allow the
1316                            user to specify an existing inode to be the
1317                            journal file. */
1318                         if (is_remount) {
1319                                 ext4_msg(sb, KERN_ERR,
1320                                          "Cannot specify journal on remount");
1321                                 return 0;
1322                         }
1323                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1324                         break;
1325                 case Opt_journal_dev:
1326                         if (is_remount) {
1327                                 ext4_msg(sb, KERN_ERR,
1328                                         "Cannot specify journal on remount");
1329                                 return 0;
1330                         }
1331                         if (match_int(&args[0], &option))
1332                                 return 0;
1333                         *journal_devnum = option;
1334                         break;
1335                 case Opt_journal_checksum:
1336                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1337                         break;
1338                 case Opt_journal_async_commit:
1339                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1340                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1341                         break;
1342                 case Opt_noload:
1343                         set_opt(sbi->s_mount_opt, NOLOAD);
1344                         break;
1345                 case Opt_commit:
1346                         if (match_int(&args[0], &option))
1347                                 return 0;
1348                         if (option < 0)
1349                                 return 0;
1350                         if (option == 0)
1351                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1352                         sbi->s_commit_interval = HZ * option;
1353                         break;
1354                 case Opt_max_batch_time:
1355                         if (match_int(&args[0], &option))
1356                                 return 0;
1357                         if (option < 0)
1358                                 return 0;
1359                         if (option == 0)
1360                                 option = EXT4_DEF_MAX_BATCH_TIME;
1361                         sbi->s_max_batch_time = option;
1362                         break;
1363                 case Opt_min_batch_time:
1364                         if (match_int(&args[0], &option))
1365                                 return 0;
1366                         if (option < 0)
1367                                 return 0;
1368                         sbi->s_min_batch_time = option;
1369                         break;
1370                 case Opt_data_journal:
1371                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1372                         goto datacheck;
1373                 case Opt_data_ordered:
1374                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1375                         goto datacheck;
1376                 case Opt_data_writeback:
1377                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1378                 datacheck:
1379                         if (is_remount) {
1380                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1381                                                 != data_opt) {
1382                                         ext4_msg(sb, KERN_ERR,
1383                                                 "Cannot change data mode on remount");
1384                                         return 0;
1385                                 }
1386                         } else {
1387                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1388                                 sbi->s_mount_opt |= data_opt;
1389                         }
1390                         break;
1391                 case Opt_data_err_abort:
1392                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1393                         break;
1394                 case Opt_data_err_ignore:
1395                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1396                         break;
1397 #ifdef CONFIG_QUOTA
1398                 case Opt_usrjquota:
1399                         qtype = USRQUOTA;
1400                         goto set_qf_name;
1401                 case Opt_grpjquota:
1402                         qtype = GRPQUOTA;
1403 set_qf_name:
1404                         if (sb_any_quota_loaded(sb) &&
1405                             !sbi->s_qf_names[qtype]) {
1406                                 ext4_msg(sb, KERN_ERR,
1407                                        "Cannot change journaled "
1408                                        "quota options when quota turned on");
1409                                 return 0;
1410                         }
1411                         qname = match_strdup(&args[0]);
1412                         if (!qname) {
1413                                 ext4_msg(sb, KERN_ERR,
1414                                         "Not enough memory for "
1415                                         "storing quotafile name");
1416                                 return 0;
1417                         }
1418                         if (sbi->s_qf_names[qtype] &&
1419                             strcmp(sbi->s_qf_names[qtype], qname)) {
1420                                 ext4_msg(sb, KERN_ERR,
1421                                         "%s quota file already "
1422                                         "specified", QTYPE2NAME(qtype));
1423                                 kfree(qname);
1424                                 return 0;
1425                         }
1426                         sbi->s_qf_names[qtype] = qname;
1427                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1428                                 ext4_msg(sb, KERN_ERR,
1429                                         "quotafile must be on "
1430                                         "filesystem root");
1431                                 kfree(sbi->s_qf_names[qtype]);
1432                                 sbi->s_qf_names[qtype] = NULL;
1433                                 return 0;
1434                         }
1435                         set_opt(sbi->s_mount_opt, QUOTA);
1436                         break;
1437                 case Opt_offusrjquota:
1438                         qtype = USRQUOTA;
1439                         goto clear_qf_name;
1440                 case Opt_offgrpjquota:
1441                         qtype = GRPQUOTA;
1442 clear_qf_name:
1443                         if (sb_any_quota_loaded(sb) &&
1444                             sbi->s_qf_names[qtype]) {
1445                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1446                                         "journaled quota options when "
1447                                         "quota turned on");
1448                                 return 0;
1449                         }
1450                         /*
1451                          * The space will be released later when all options
1452                          * are confirmed to be correct
1453                          */
1454                         sbi->s_qf_names[qtype] = NULL;
1455                         break;
1456                 case Opt_jqfmt_vfsold:
1457                         qfmt = QFMT_VFS_OLD;
1458                         goto set_qf_format;
1459                 case Opt_jqfmt_vfsv0:
1460                         qfmt = QFMT_VFS_V0;
1461                         goto set_qf_format;
1462                 case Opt_jqfmt_vfsv1:
1463                         qfmt = QFMT_VFS_V1;
1464 set_qf_format:
1465                         if (sb_any_quota_loaded(sb) &&
1466                             sbi->s_jquota_fmt != qfmt) {
1467                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1468                                         "journaled quota options when "
1469                                         "quota turned on");
1470                                 return 0;
1471                         }
1472                         sbi->s_jquota_fmt = qfmt;
1473                         break;
1474                 case Opt_quota:
1475                 case Opt_usrquota:
1476                         set_opt(sbi->s_mount_opt, QUOTA);
1477                         set_opt(sbi->s_mount_opt, USRQUOTA);
1478                         break;
1479                 case Opt_grpquota:
1480                         set_opt(sbi->s_mount_opt, QUOTA);
1481                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1482                         break;
1483                 case Opt_noquota:
1484                         if (sb_any_quota_loaded(sb)) {
1485                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1486                                         "options when quota turned on");
1487                                 return 0;
1488                         }
1489                         clear_opt(sbi->s_mount_opt, QUOTA);
1490                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1491                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1492                         break;
1493 #else
1494                 case Opt_quota:
1495                 case Opt_usrquota:
1496                 case Opt_grpquota:
1497                         ext4_msg(sb, KERN_ERR,
1498                                 "quota options not supported");
1499                         break;
1500                 case Opt_usrjquota:
1501                 case Opt_grpjquota:
1502                 case Opt_offusrjquota:
1503                 case Opt_offgrpjquota:
1504                 case Opt_jqfmt_vfsold:
1505                 case Opt_jqfmt_vfsv0:
1506                 case Opt_jqfmt_vfsv1:
1507                         ext4_msg(sb, KERN_ERR,
1508                                 "journaled quota options not supported");
1509                         break;
1510                 case Opt_noquota:
1511                         break;
1512 #endif
1513                 case Opt_abort:
1514                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1515                         break;
1516                 case Opt_nobarrier:
1517                         clear_opt(sbi->s_mount_opt, BARRIER);
1518                         break;
1519                 case Opt_barrier:
1520                         if (match_int(&args[0], &option)) {
1521                                 set_opt(sbi->s_mount_opt, BARRIER);
1522                                 break;
1523                         }
1524                         if (option)
1525                                 set_opt(sbi->s_mount_opt, BARRIER);
1526                         else
1527                                 clear_opt(sbi->s_mount_opt, BARRIER);
1528                         break;
1529                 case Opt_ignore:
1530                         break;
1531                 case Opt_resize:
1532                         if (!is_remount) {
1533                                 ext4_msg(sb, KERN_ERR,
1534                                         "resize option only available "
1535                                         "for remount");
1536                                 return 0;
1537                         }
1538                         if (match_int(&args[0], &option) != 0)
1539                                 return 0;
1540                         *n_blocks_count = option;
1541                         break;
1542                 case Opt_nobh:
1543                         set_opt(sbi->s_mount_opt, NOBH);
1544                         break;
1545                 case Opt_bh:
1546                         clear_opt(sbi->s_mount_opt, NOBH);
1547                         break;
1548                 case Opt_i_version:
1549                         set_opt(sbi->s_mount_opt, I_VERSION);
1550                         sb->s_flags |= MS_I_VERSION;
1551                         break;
1552                 case Opt_nodelalloc:
1553                         clear_opt(sbi->s_mount_opt, DELALLOC);
1554                         break;
1555                 case Opt_stripe:
1556                         if (match_int(&args[0], &option))
1557                                 return 0;
1558                         if (option < 0)
1559                                 return 0;
1560                         sbi->s_stripe = option;
1561                         break;
1562                 case Opt_delalloc:
1563                         set_opt(sbi->s_mount_opt, DELALLOC);
1564                         break;
1565                 case Opt_block_validity:
1566                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1567                         break;
1568                 case Opt_noblock_validity:
1569                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1570                         break;
1571                 case Opt_inode_readahead_blks:
1572                         if (match_int(&args[0], &option))
1573                                 return 0;
1574                         if (option < 0 || option > (1 << 30))
1575                                 return 0;
1576                         if (!is_power_of_2(option)) {
1577                                 ext4_msg(sb, KERN_ERR,
1578                                          "EXT4-fs: inode_readahead_blks"
1579                                          " must be a power of 2");
1580                                 return 0;
1581                         }
1582                         sbi->s_inode_readahead_blks = option;
1583                         break;
1584                 case Opt_journal_ioprio:
1585                         if (match_int(&args[0], &option))
1586                                 return 0;
1587                         if (option < 0 || option > 7)
1588                                 break;
1589                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1590                                                             option);
1591                         break;
1592                 case Opt_noauto_da_alloc:
1593                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1594                         break;
1595                 case Opt_auto_da_alloc:
1596                         if (match_int(&args[0], &option)) {
1597                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1598                                 break;
1599                         }
1600                         if (option)
1601                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1602                         else
1603                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1604                         break;
1605                 case Opt_discard:
1606                         set_opt(sbi->s_mount_opt, DISCARD);
1607                         break;
1608                 case Opt_nodiscard:
1609                         clear_opt(sbi->s_mount_opt, DISCARD);
1610                         break;
1611                 default:
1612                         ext4_msg(sb, KERN_ERR,
1613                                "Unrecognized mount option \"%s\" "
1614                                "or missing value", p);
1615                         return 0;
1616                 }
1617         }
1618 #ifdef CONFIG_QUOTA
1619         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1620                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1621                      sbi->s_qf_names[USRQUOTA])
1622                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1623
1624                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1625                      sbi->s_qf_names[GRPQUOTA])
1626                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1627
1628                 if ((sbi->s_qf_names[USRQUOTA] &&
1629                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1630                     (sbi->s_qf_names[GRPQUOTA] &&
1631                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1632                         ext4_msg(sb, KERN_ERR, "old and new quota "
1633                                         "format mixing");
1634                         return 0;
1635                 }
1636
1637                 if (!sbi->s_jquota_fmt) {
1638                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1639                                         "not specified");
1640                         return 0;
1641                 }
1642         } else {
1643                 if (sbi->s_jquota_fmt) {
1644                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1645                                         "specified with no journaling "
1646                                         "enabled");
1647                         return 0;
1648                 }
1649         }
1650 #endif
1651         return 1;
1652 }
1653
1654 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1655                             int read_only)
1656 {
1657         struct ext4_sb_info *sbi = EXT4_SB(sb);
1658         int res = 0;
1659
1660         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1661                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1662                          "forcing read-only mode");
1663                 res = MS_RDONLY;
1664         }
1665         if (read_only)
1666                 return res;
1667         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1668                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1669                          "running e2fsck is recommended");
1670         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1671                 ext4_msg(sb, KERN_WARNING,
1672                          "warning: mounting fs with errors, "
1673                          "running e2fsck is recommended");
1674         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1675                  le16_to_cpu(es->s_mnt_count) >=
1676                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1677                 ext4_msg(sb, KERN_WARNING,
1678                          "warning: maximal mount count reached, "
1679                          "running e2fsck is recommended");
1680         else if (le32_to_cpu(es->s_checkinterval) &&
1681                 (le32_to_cpu(es->s_lastcheck) +
1682                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1683                 ext4_msg(sb, KERN_WARNING,
1684                          "warning: checktime reached, "
1685                          "running e2fsck is recommended");
1686         if (!sbi->s_journal)
1687                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1688         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1689                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1690         le16_add_cpu(&es->s_mnt_count, 1);
1691         es->s_mtime = cpu_to_le32(get_seconds());
1692         ext4_update_dynamic_rev(sb);
1693         if (sbi->s_journal)
1694                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1695
1696         ext4_commit_super(sb, 1);
1697         if (test_opt(sb, DEBUG))
1698                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1699                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1700                         sb->s_blocksize,
1701                         sbi->s_groups_count,
1702                         EXT4_BLOCKS_PER_GROUP(sb),
1703                         EXT4_INODES_PER_GROUP(sb),
1704                         sbi->s_mount_opt);
1705
1706         return res;
1707 }
1708
1709 static int ext4_fill_flex_info(struct super_block *sb)
1710 {
1711         struct ext4_sb_info *sbi = EXT4_SB(sb);
1712         struct ext4_group_desc *gdp = NULL;
1713         ext4_group_t flex_group_count;
1714         ext4_group_t flex_group;
1715         int groups_per_flex = 0;
1716         size_t size;
1717         int i;
1718
1719         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1720         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1721
1722         if (groups_per_flex < 2) {
1723                 sbi->s_log_groups_per_flex = 0;
1724                 return 1;
1725         }
1726
1727         /* We allocate both existing and potentially added groups */
1728         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1729                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1730                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1731         size = flex_group_count * sizeof(struct flex_groups);
1732         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1733         if (sbi->s_flex_groups == NULL) {
1734                 sbi->s_flex_groups = vmalloc(size);
1735                 if (sbi->s_flex_groups)
1736                         memset(sbi->s_flex_groups, 0, size);
1737         }
1738         if (sbi->s_flex_groups == NULL) {
1739                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1740                                 "%u flex groups", flex_group_count);
1741                 goto failed;
1742         }
1743
1744         for (i = 0; i < sbi->s_groups_count; i++) {
1745                 gdp = ext4_get_group_desc(sb, i, NULL);
1746
1747                 flex_group = ext4_flex_group(sbi, i);
1748                 atomic_add(ext4_free_inodes_count(sb, gdp),
1749                            &sbi->s_flex_groups[flex_group].free_inodes);
1750                 atomic_add(ext4_free_blks_count(sb, gdp),
1751                            &sbi->s_flex_groups[flex_group].free_blocks);
1752                 atomic_add(ext4_used_dirs_count(sb, gdp),
1753                            &sbi->s_flex_groups[flex_group].used_dirs);
1754         }
1755
1756         return 1;
1757 failed:
1758         return 0;
1759 }
1760
1761 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1762                             struct ext4_group_desc *gdp)
1763 {
1764         __u16 crc = 0;
1765
1766         if (sbi->s_es->s_feature_ro_compat &
1767             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1768                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1769                 __le32 le_group = cpu_to_le32(block_group);
1770
1771                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1772                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1773                 crc = crc16(crc, (__u8 *)gdp, offset);
1774                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1775                 /* for checksum of struct ext4_group_desc do the rest...*/
1776                 if ((sbi->s_es->s_feature_incompat &
1777                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1778                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1779                         crc = crc16(crc, (__u8 *)gdp + offset,
1780                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1781                                         offset);
1782         }
1783
1784         return cpu_to_le16(crc);
1785 }
1786
1787 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1788                                 struct ext4_group_desc *gdp)
1789 {
1790         if ((sbi->s_es->s_feature_ro_compat &
1791              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1792             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1793                 return 0;
1794
1795         return 1;
1796 }
1797
1798 /* Called at mount-time, super-block is locked */
1799 static int ext4_check_descriptors(struct super_block *sb)
1800 {
1801         struct ext4_sb_info *sbi = EXT4_SB(sb);
1802         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1803         ext4_fsblk_t last_block;
1804         ext4_fsblk_t block_bitmap;
1805         ext4_fsblk_t inode_bitmap;
1806         ext4_fsblk_t inode_table;
1807         int flexbg_flag = 0;
1808         ext4_group_t i;
1809
1810         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1811                 flexbg_flag = 1;
1812
1813         ext4_debug("Checking group descriptors");
1814
1815         for (i = 0; i < sbi->s_groups_count; i++) {
1816                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1817
1818                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1819                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1820                 else
1821                         last_block = first_block +
1822                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1823
1824                 block_bitmap = ext4_block_bitmap(sb, gdp);
1825                 if (block_bitmap < first_block || block_bitmap > last_block) {
1826                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1827                                "Block bitmap for group %u not in group "
1828                                "(block %llu)!", i, block_bitmap);
1829                         return 0;
1830                 }
1831                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1832                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1833                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1834                                "Inode bitmap for group %u not in group "
1835                                "(block %llu)!", i, inode_bitmap);
1836                         return 0;
1837                 }
1838                 inode_table = ext4_inode_table(sb, gdp);
1839                 if (inode_table < first_block ||
1840                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1841                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1842                                "Inode table for group %u not in group "
1843                                "(block %llu)!", i, inode_table);
1844                         return 0;
1845                 }
1846                 ext4_lock_group(sb, i);
1847                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1848                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1849                                  "Checksum for group %u failed (%u!=%u)",
1850                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1851                                      gdp)), le16_to_cpu(gdp->bg_checksum));
1852                         if (!(sb->s_flags & MS_RDONLY)) {
1853                                 ext4_unlock_group(sb, i);
1854                                 return 0;
1855                         }
1856                 }
1857                 ext4_unlock_group(sb, i);
1858                 if (!flexbg_flag)
1859                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1860         }
1861
1862         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1863         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1864         return 1;
1865 }
1866
1867 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1868  * the superblock) which were deleted from all directories, but held open by
1869  * a process at the time of a crash.  We walk the list and try to delete these
1870  * inodes at recovery time (only with a read-write filesystem).
1871  *
1872  * In order to keep the orphan inode chain consistent during traversal (in
1873  * case of crash during recovery), we link each inode into the superblock
1874  * orphan list_head and handle it the same way as an inode deletion during
1875  * normal operation (which journals the operations for us).
1876  *
1877  * We only do an iget() and an iput() on each inode, which is very safe if we
1878  * accidentally point at an in-use or already deleted inode.  The worst that
1879  * can happen in this case is that we get a "bit already cleared" message from
1880  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1881  * e2fsck was run on this filesystem, and it must have already done the orphan
1882  * inode cleanup for us, so we can safely abort without any further action.
1883  */
1884 static void ext4_orphan_cleanup(struct super_block *sb,
1885                                 struct ext4_super_block *es)
1886 {
1887         unsigned int s_flags = sb->s_flags;
1888         int nr_orphans = 0, nr_truncates = 0;
1889 #ifdef CONFIG_QUOTA
1890         int i;
1891 #endif
1892         if (!es->s_last_orphan) {
1893                 jbd_debug(4, "no orphan inodes to clean up\n");
1894                 return;
1895         }
1896
1897         if (bdev_read_only(sb->s_bdev)) {
1898                 ext4_msg(sb, KERN_ERR, "write access "
1899                         "unavailable, skipping orphan cleanup");
1900                 return;
1901         }
1902
1903         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1904                 if (es->s_last_orphan)
1905                         jbd_debug(1, "Errors on filesystem, "
1906                                   "clearing orphan list.\n");
1907                 es->s_last_orphan = 0;
1908                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1909                 return;
1910         }
1911
1912         if (s_flags & MS_RDONLY) {
1913                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
1914                 sb->s_flags &= ~MS_RDONLY;
1915         }
1916 #ifdef CONFIG_QUOTA
1917         /* Needed for iput() to work correctly and not trash data */
1918         sb->s_flags |= MS_ACTIVE;
1919         /* Turn on quotas so that they are updated correctly */
1920         for (i = 0; i < MAXQUOTAS; i++) {
1921                 if (EXT4_SB(sb)->s_qf_names[i]) {
1922                         int ret = ext4_quota_on_mount(sb, i);
1923                         if (ret < 0)
1924                                 ext4_msg(sb, KERN_ERR,
1925                                         "Cannot turn on journaled "
1926                                         "quota: error %d", ret);
1927                 }
1928         }
1929 #endif
1930
1931         while (es->s_last_orphan) {
1932                 struct inode *inode;
1933
1934                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1935                 if (IS_ERR(inode)) {
1936                         es->s_last_orphan = 0;
1937                         break;
1938                 }
1939
1940                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1941                 vfs_dq_init(inode);
1942                 if (inode->i_nlink) {
1943                         ext4_msg(sb, KERN_DEBUG,
1944                                 "%s: truncating inode %lu to %lld bytes",
1945                                 __func__, inode->i_ino, inode->i_size);
1946                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1947                                   inode->i_ino, inode->i_size);
1948                         ext4_truncate(inode);
1949                         nr_truncates++;
1950                 } else {
1951                         ext4_msg(sb, KERN_DEBUG,
1952                                 "%s: deleting unreferenced inode %lu",
1953                                 __func__, inode->i_ino);
1954                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1955                                   inode->i_ino);
1956                         nr_orphans++;
1957                 }
1958                 iput(inode);  /* The delete magic happens here! */
1959         }
1960
1961 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1962
1963         if (nr_orphans)
1964                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
1965                        PLURAL(nr_orphans));
1966         if (nr_truncates)
1967                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
1968                        PLURAL(nr_truncates));
1969 #ifdef CONFIG_QUOTA
1970         /* Turn quotas off */
1971         for (i = 0; i < MAXQUOTAS; i++) {
1972                 if (sb_dqopt(sb)->files[i])
1973                         vfs_quota_off(sb, i, 0);
1974         }
1975 #endif
1976         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1977 }
1978
1979 /*
1980  * Maximal extent format file size.
1981  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1982  * extent format containers, within a sector_t, and within i_blocks
1983  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1984  * so that won't be a limiting factor.
1985  *
1986  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1987  */
1988 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1989 {
1990         loff_t res;
1991         loff_t upper_limit = MAX_LFS_FILESIZE;
1992
1993         /* small i_blocks in vfs inode? */
1994         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1995                 /*
1996                  * CONFIG_LBDAF is not enabled implies the inode
1997                  * i_block represent total blocks in 512 bytes
1998                  * 32 == size of vfs inode i_blocks * 8
1999                  */
2000                 upper_limit = (1LL << 32) - 1;
2001
2002                 /* total blocks in file system block size */
2003                 upper_limit >>= (blkbits - 9);
2004                 upper_limit <<= blkbits;
2005         }
2006
2007         /* 32-bit extent-start container, ee_block */
2008         res = 1LL << 32;
2009         res <<= blkbits;
2010         res -= 1;
2011
2012         /* Sanity check against vm- & vfs- imposed limits */
2013         if (res > upper_limit)
2014                 res = upper_limit;
2015
2016         return res;
2017 }
2018
2019 /*
2020  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2021  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2022  * We need to be 1 filesystem block less than the 2^48 sector limit.
2023  */
2024 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2025 {
2026         loff_t res = EXT4_NDIR_BLOCKS;
2027         int meta_blocks;
2028         loff_t upper_limit;
2029         /* This is calculated to be the largest file size for a dense, block
2030          * mapped file such that the file's total number of 512-byte sectors,
2031          * including data and all indirect blocks, does not exceed (2^48 - 1).
2032          *
2033          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2034          * number of 512-byte sectors of the file.
2035          */
2036
2037         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2038                 /*
2039                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2040                  * the inode i_block field represents total file blocks in
2041                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2042                  */
2043                 upper_limit = (1LL << 32) - 1;
2044
2045                 /* total blocks in file system block size */
2046                 upper_limit >>= (bits - 9);
2047
2048         } else {
2049                 /*
2050                  * We use 48 bit ext4_inode i_blocks
2051                  * With EXT4_HUGE_FILE_FL set the i_blocks
2052                  * represent total number of blocks in
2053                  * file system block size
2054                  */
2055                 upper_limit = (1LL << 48) - 1;
2056
2057         }
2058
2059         /* indirect blocks */
2060         meta_blocks = 1;
2061         /* double indirect blocks */
2062         meta_blocks += 1 + (1LL << (bits-2));
2063         /* tripple indirect blocks */
2064         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2065
2066         upper_limit -= meta_blocks;
2067         upper_limit <<= bits;
2068
2069         res += 1LL << (bits-2);
2070         res += 1LL << (2*(bits-2));
2071         res += 1LL << (3*(bits-2));
2072         res <<= bits;
2073         if (res > upper_limit)
2074                 res = upper_limit;
2075
2076         if (res > MAX_LFS_FILESIZE)
2077                 res = MAX_LFS_FILESIZE;
2078
2079         return res;
2080 }
2081
2082 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2083                                    ext4_fsblk_t logical_sb_block, int nr)
2084 {
2085         struct ext4_sb_info *sbi = EXT4_SB(sb);
2086         ext4_group_t bg, first_meta_bg;
2087         int has_super = 0;
2088
2089         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2090
2091         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2092             nr < first_meta_bg)
2093                 return logical_sb_block + nr + 1;
2094         bg = sbi->s_desc_per_block * nr;
2095         if (ext4_bg_has_super(sb, bg))
2096                 has_super = 1;
2097
2098         return (has_super + ext4_group_first_block_no(sb, bg));
2099 }
2100
2101 /**
2102  * ext4_get_stripe_size: Get the stripe size.
2103  * @sbi: In memory super block info
2104  *
2105  * If we have specified it via mount option, then
2106  * use the mount option value. If the value specified at mount time is
2107  * greater than the blocks per group use the super block value.
2108  * If the super block value is greater than blocks per group return 0.
2109  * Allocator needs it be less than blocks per group.
2110  *
2111  */
2112 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2113 {
2114         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2115         unsigned long stripe_width =
2116                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2117
2118         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2119                 return sbi->s_stripe;
2120
2121         if (stripe_width <= sbi->s_blocks_per_group)
2122                 return stripe_width;
2123
2124         if (stride <= sbi->s_blocks_per_group)
2125                 return stride;
2126
2127         return 0;
2128 }
2129
2130 /* sysfs supprt */
2131
2132 struct ext4_attr {
2133         struct attribute attr;
2134         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2135         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *, 
2136                          const char *, size_t);
2137         int offset;
2138 };
2139
2140 static int parse_strtoul(const char *buf,
2141                 unsigned long max, unsigned long *value)
2142 {
2143         char *endp;
2144
2145         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2146         endp = skip_spaces(endp);
2147         if (*endp || *value > max)
2148                 return -EINVAL;
2149
2150         return 0;
2151 }
2152
2153 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2154                                               struct ext4_sb_info *sbi,
2155                                               char *buf)
2156 {
2157         return snprintf(buf, PAGE_SIZE, "%llu\n",
2158                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2159 }
2160
2161 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2162                                          struct ext4_sb_info *sbi, char *buf)
2163 {
2164         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2165
2166         return snprintf(buf, PAGE_SIZE, "%lu\n",
2167                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2168                          sbi->s_sectors_written_start) >> 1);
2169 }
2170
2171 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2172                                           struct ext4_sb_info *sbi, char *buf)
2173 {
2174         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2175
2176         return snprintf(buf, PAGE_SIZE, "%llu\n",
2177                         sbi->s_kbytes_written + 
2178                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2179                           EXT4_SB(sb)->s_sectors_written_start) >> 1));
2180 }
2181
2182 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2183                                           struct ext4_sb_info *sbi,
2184                                           const char *buf, size_t count)
2185 {
2186         unsigned long t;
2187
2188         if (parse_strtoul(buf, 0x40000000, &t))
2189                 return -EINVAL;
2190
2191         if (!is_power_of_2(t))
2192                 return -EINVAL;
2193
2194         sbi->s_inode_readahead_blks = t;
2195         return count;
2196 }
2197
2198 static ssize_t sbi_ui_show(struct ext4_attr *a,
2199                            struct ext4_sb_info *sbi, char *buf)
2200 {
2201         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2202
2203         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2204 }
2205
2206 static ssize_t sbi_ui_store(struct ext4_attr *a,
2207                             struct ext4_sb_info *sbi,
2208                             const char *buf, size_t count)
2209 {
2210         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2211         unsigned long t;
2212
2213         if (parse_strtoul(buf, 0xffffffff, &t))
2214                 return -EINVAL;
2215         *ui = t;
2216         return count;
2217 }
2218
2219 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2220 static struct ext4_attr ext4_attr_##_name = {                   \
2221         .attr = {.name = __stringify(_name), .mode = _mode },   \
2222         .show   = _show,                                        \
2223         .store  = _store,                                       \
2224         .offset = offsetof(struct ext4_sb_info, _elname),       \
2225 }
2226 #define EXT4_ATTR(name, mode, show, store) \
2227 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2228
2229 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2230 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2231 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2232         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2233 #define ATTR_LIST(name) &ext4_attr_##name.attr
2234
2235 EXT4_RO_ATTR(delayed_allocation_blocks);
2236 EXT4_RO_ATTR(session_write_kbytes);
2237 EXT4_RO_ATTR(lifetime_write_kbytes);
2238 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2239                  inode_readahead_blks_store, s_inode_readahead_blks);
2240 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2241 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2242 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2243 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2244 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2245 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2246 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2247 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2248
2249 static struct attribute *ext4_attrs[] = {
2250         ATTR_LIST(delayed_allocation_blocks),
2251         ATTR_LIST(session_write_kbytes),
2252         ATTR_LIST(lifetime_write_kbytes),
2253         ATTR_LIST(inode_readahead_blks),
2254         ATTR_LIST(inode_goal),
2255         ATTR_LIST(mb_stats),
2256         ATTR_LIST(mb_max_to_scan),
2257         ATTR_LIST(mb_min_to_scan),
2258         ATTR_LIST(mb_order2_req),
2259         ATTR_LIST(mb_stream_req),
2260         ATTR_LIST(mb_group_prealloc),
2261         ATTR_LIST(max_writeback_mb_bump),
2262         NULL,
2263 };
2264
2265 static ssize_t ext4_attr_show(struct kobject *kobj,
2266                               struct attribute *attr, char *buf)
2267 {
2268         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2269                                                 s_kobj);
2270         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2271
2272         return a->show ? a->show(a, sbi, buf) : 0;
2273 }
2274
2275 static ssize_t ext4_attr_store(struct kobject *kobj,
2276                                struct attribute *attr,
2277                                const char *buf, size_t len)
2278 {
2279         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2280                                                 s_kobj);
2281         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2282
2283         return a->store ? a->store(a, sbi, buf, len) : 0;
2284 }
2285
2286 static void ext4_sb_release(struct kobject *kobj)
2287 {
2288         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2289                                                 s_kobj);
2290         complete(&sbi->s_kobj_unregister);
2291 }
2292
2293
2294 static struct sysfs_ops ext4_attr_ops = {
2295         .show   = ext4_attr_show,
2296         .store  = ext4_attr_store,
2297 };
2298
2299 static struct kobj_type ext4_ktype = {
2300         .default_attrs  = ext4_attrs,
2301         .sysfs_ops      = &ext4_attr_ops,
2302         .release        = ext4_sb_release,
2303 };
2304
2305 /*
2306  * Check whether this filesystem can be mounted based on
2307  * the features present and the RDONLY/RDWR mount requested.
2308  * Returns 1 if this filesystem can be mounted as requested,
2309  * 0 if it cannot be.
2310  */
2311 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2312 {
2313         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2314                 ext4_msg(sb, KERN_ERR,
2315                         "Couldn't mount because of "
2316                         "unsupported optional features (%x)",
2317                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2318                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2319                 return 0;
2320         }
2321
2322         if (readonly)
2323                 return 1;
2324
2325         /* Check that feature set is OK for a read-write mount */
2326         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2327                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2328                          "unsupported optional features (%x)",
2329                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2330                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2331                 return 0;
2332         }
2333         /*
2334          * Large file size enabled file system can only be mounted
2335          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2336          */
2337         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2338                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2339                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2340                                  "cannot be mounted RDWR without "
2341                                  "CONFIG_LBDAF");
2342                         return 0;
2343                 }
2344         }
2345         return 1;
2346 }
2347
2348 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2349                                 __releases(kernel_lock)
2350                                 __acquires(kernel_lock)
2351 {
2352         struct buffer_head *bh;
2353         struct ext4_super_block *es = NULL;
2354         struct ext4_sb_info *sbi;
2355         ext4_fsblk_t block;
2356         ext4_fsblk_t sb_block = get_sb_block(&data);
2357         ext4_fsblk_t logical_sb_block;
2358         unsigned long offset = 0;
2359         unsigned long journal_devnum = 0;
2360         unsigned long def_mount_opts;
2361         struct inode *root;
2362         char *cp;
2363         const char *descr;
2364         int ret = -EINVAL;
2365         int blocksize;
2366         unsigned int db_count;
2367         unsigned int i;
2368         int needs_recovery, has_huge_files;
2369         __u64 blocks_count;
2370         int err;
2371         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2372
2373         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2374         if (!sbi)
2375                 return -ENOMEM;
2376
2377         sbi->s_blockgroup_lock =
2378                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2379         if (!sbi->s_blockgroup_lock) {
2380                 kfree(sbi);
2381                 return -ENOMEM;
2382         }
2383         sb->s_fs_info = sbi;
2384         sbi->s_mount_opt = 0;
2385         sbi->s_resuid = EXT4_DEF_RESUID;
2386         sbi->s_resgid = EXT4_DEF_RESGID;
2387         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2388         sbi->s_sb_block = sb_block;
2389         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2390                                                       sectors[1]);
2391
2392         unlock_kernel();
2393
2394         /* Cleanup superblock name */
2395         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2396                 *cp = '!';
2397
2398         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2399         if (!blocksize) {
2400                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2401                 goto out_fail;
2402         }
2403
2404         /*
2405          * The ext4 superblock will not be buffer aligned for other than 1kB
2406          * block sizes.  We need to calculate the offset from buffer start.
2407          */
2408         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2409                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2410                 offset = do_div(logical_sb_block, blocksize);
2411         } else {
2412                 logical_sb_block = sb_block;
2413         }
2414
2415         if (!(bh = sb_bread(sb, logical_sb_block))) {
2416                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2417                 goto out_fail;
2418         }
2419         /*
2420          * Note: s_es must be initialized as soon as possible because
2421          *       some ext4 macro-instructions depend on its value
2422          */
2423         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2424         sbi->s_es = es;
2425         sb->s_magic = le16_to_cpu(es->s_magic);
2426         if (sb->s_magic != EXT4_SUPER_MAGIC)
2427                 goto cantfind_ext4;
2428         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2429
2430         /* Set defaults before we parse the mount options */
2431         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2432         if (def_mount_opts & EXT4_DEFM_DEBUG)
2433                 set_opt(sbi->s_mount_opt, DEBUG);
2434         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
2435                 set_opt(sbi->s_mount_opt, GRPID);
2436         if (def_mount_opts & EXT4_DEFM_UID16)
2437                 set_opt(sbi->s_mount_opt, NO_UID32);
2438 #ifdef CONFIG_EXT4_FS_XATTR
2439         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2440                 set_opt(sbi->s_mount_opt, XATTR_USER);
2441 #endif
2442 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2443         if (def_mount_opts & EXT4_DEFM_ACL)
2444                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2445 #endif
2446         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2447                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2448         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2449                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2450         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2451                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2452
2453         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2454                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2455         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2456                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2457         else
2458                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2459
2460         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2461         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2462         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2463         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2464         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2465
2466         set_opt(sbi->s_mount_opt, BARRIER);
2467
2468         /*
2469          * enable delayed allocation by default
2470          * Use -o nodelalloc to turn it off
2471          */
2472         set_opt(sbi->s_mount_opt, DELALLOC);
2473
2474         if (!parse_options((char *) data, sb, &journal_devnum,
2475                            &journal_ioprio, NULL, 0))
2476                 goto failed_mount;
2477
2478         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2479                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2480
2481         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2482             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2483              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2484              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2485                 ext4_msg(sb, KERN_WARNING,
2486                        "feature flags set on rev 0 fs, "
2487                        "running e2fsck is recommended");
2488
2489         /*
2490          * Check feature flags regardless of the revision level, since we
2491          * previously didn't change the revision level when setting the flags,
2492          * so there is a chance incompat flags are set on a rev 0 filesystem.
2493          */
2494         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
2495                 goto failed_mount;
2496
2497         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2498
2499         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2500             blocksize > EXT4_MAX_BLOCK_SIZE) {
2501                 ext4_msg(sb, KERN_ERR,
2502                        "Unsupported filesystem blocksize %d", blocksize);
2503                 goto failed_mount;
2504         }
2505
2506         if (sb->s_blocksize != blocksize) {
2507                 /* Validate the filesystem blocksize */
2508                 if (!sb_set_blocksize(sb, blocksize)) {
2509                         ext4_msg(sb, KERN_ERR, "bad block size %d",
2510                                         blocksize);
2511                         goto failed_mount;
2512                 }
2513
2514                 brelse(bh);
2515                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2516                 offset = do_div(logical_sb_block, blocksize);
2517                 bh = sb_bread(sb, logical_sb_block);
2518                 if (!bh) {
2519                         ext4_msg(sb, KERN_ERR,
2520                                "Can't read superblock on 2nd try");
2521                         goto failed_mount;
2522                 }
2523                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2524                 sbi->s_es = es;
2525                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2526                         ext4_msg(sb, KERN_ERR,
2527                                "Magic mismatch, very weird!");
2528                         goto failed_mount;
2529                 }
2530         }
2531
2532         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2533                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2534         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2535                                                       has_huge_files);
2536         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2537
2538         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2539                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2540                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2541         } else {
2542                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2543                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2544                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2545                     (!is_power_of_2(sbi->s_inode_size)) ||
2546                     (sbi->s_inode_size > blocksize)) {
2547                         ext4_msg(sb, KERN_ERR,
2548                                "unsupported inode size: %d",
2549                                sbi->s_inode_size);
2550                         goto failed_mount;
2551                 }
2552                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2553                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2554         }
2555
2556         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2557         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2558                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2559                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2560                     !is_power_of_2(sbi->s_desc_size)) {
2561                         ext4_msg(sb, KERN_ERR,
2562                                "unsupported descriptor size %lu",
2563                                sbi->s_desc_size);
2564                         goto failed_mount;
2565                 }
2566         } else
2567                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2568
2569         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2570         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2571         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2572                 goto cantfind_ext4;
2573
2574         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2575         if (sbi->s_inodes_per_block == 0)
2576                 goto cantfind_ext4;
2577         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2578                                         sbi->s_inodes_per_block;
2579         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2580         sbi->s_sbh = bh;
2581         sbi->s_mount_state = le16_to_cpu(es->s_state);
2582         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2583         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2584
2585         for (i = 0; i < 4; i++)
2586                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2587         sbi->s_def_hash_version = es->s_def_hash_version;
2588         i = le32_to_cpu(es->s_flags);
2589         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2590                 sbi->s_hash_unsigned = 3;
2591         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2592 #ifdef __CHAR_UNSIGNED__
2593                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2594                 sbi->s_hash_unsigned = 3;
2595 #else
2596                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2597 #endif
2598                 sb->s_dirt = 1;
2599         }
2600
2601         if (sbi->s_blocks_per_group > blocksize * 8) {
2602                 ext4_msg(sb, KERN_ERR,
2603                        "#blocks per group too big: %lu",
2604                        sbi->s_blocks_per_group);
2605                 goto failed_mount;
2606         }
2607         if (sbi->s_inodes_per_group > blocksize * 8) {
2608                 ext4_msg(sb, KERN_ERR,
2609                        "#inodes per group too big: %lu",
2610                        sbi->s_inodes_per_group);
2611                 goto failed_mount;
2612         }
2613
2614         /*
2615          * Test whether we have more sectors than will fit in sector_t,
2616          * and whether the max offset is addressable by the page cache.
2617          */
2618         if ((ext4_blocks_count(es) >
2619              (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
2620             (ext4_blocks_count(es) >
2621              (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
2622                 ext4_msg(sb, KERN_ERR, "filesystem"
2623                          " too large to mount safely on this system");
2624                 if (sizeof(sector_t) < 8)
2625                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
2626                 ret = -EFBIG;
2627                 goto failed_mount;
2628         }
2629
2630         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2631                 goto cantfind_ext4;
2632
2633         /* check blocks count against device size */
2634         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2635         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2636                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2637                        "exceeds size of device (%llu blocks)",
2638                        ext4_blocks_count(es), blocks_count);
2639                 goto failed_mount;
2640         }
2641
2642         /*
2643          * It makes no sense for the first data block to be beyond the end
2644          * of the filesystem.
2645          */
2646         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2647                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2648                          "block %u is beyond end of filesystem (%llu)",
2649                          le32_to_cpu(es->s_first_data_block),
2650                          ext4_blocks_count(es));
2651                 goto failed_mount;
2652         }
2653         blocks_count = (ext4_blocks_count(es) -
2654                         le32_to_cpu(es->s_first_data_block) +
2655                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2656         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2657         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2658                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2659                        "(block count %llu, first data block %u, "
2660                        "blocks per group %lu)", sbi->s_groups_count,
2661                        ext4_blocks_count(es),
2662                        le32_to_cpu(es->s_first_data_block),
2663                        EXT4_BLOCKS_PER_GROUP(sb));
2664                 goto failed_mount;
2665         }
2666         sbi->s_groups_count = blocks_count;
2667         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
2668                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
2669         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2670                    EXT4_DESC_PER_BLOCK(sb);
2671         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2672                                     GFP_KERNEL);
2673         if (sbi->s_group_desc == NULL) {
2674                 ext4_msg(sb, KERN_ERR, "not enough memory");
2675                 goto failed_mount;
2676         }
2677
2678 #ifdef CONFIG_PROC_FS
2679         if (ext4_proc_root)
2680                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2681 #endif
2682
2683         bgl_lock_init(sbi->s_blockgroup_lock);
2684
2685         for (i = 0; i < db_count; i++) {
2686                 block = descriptor_loc(sb, logical_sb_block, i);
2687                 sbi->s_group_desc[i] = sb_bread(sb, block);
2688                 if (!sbi->s_group_desc[i]) {
2689                         ext4_msg(sb, KERN_ERR,
2690                                "can't read group descriptor %d", i);
2691                         db_count = i;
2692                         goto failed_mount2;
2693                 }
2694         }
2695         if (!ext4_check_descriptors(sb)) {
2696                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2697                 goto failed_mount2;
2698         }
2699         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2700                 if (!ext4_fill_flex_info(sb)) {
2701                         ext4_msg(sb, KERN_ERR,
2702                                "unable to initialize "
2703                                "flex_bg meta info!");
2704                         goto failed_mount2;
2705                 }
2706
2707         sbi->s_gdb_count = db_count;
2708         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2709         spin_lock_init(&sbi->s_next_gen_lock);
2710
2711         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2712                         ext4_count_free_blocks(sb));
2713         if (!err) {
2714                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2715                                 ext4_count_free_inodes(sb));
2716         }
2717         if (!err) {
2718                 err = percpu_counter_init(&sbi->s_dirs_counter,
2719                                 ext4_count_dirs(sb));
2720         }
2721         if (!err) {
2722                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2723         }
2724         if (err) {
2725                 ext4_msg(sb, KERN_ERR, "insufficient memory");
2726                 goto failed_mount3;
2727         }
2728
2729         sbi->s_stripe = ext4_get_stripe_size(sbi);
2730         sbi->s_max_writeback_mb_bump = 128;
2731
2732         /*
2733          * set up enough so that it can read an inode
2734          */
2735         if (!test_opt(sb, NOLOAD) &&
2736             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2737                 sb->s_op = &ext4_sops;
2738         else
2739                 sb->s_op = &ext4_nojournal_sops;
2740         sb->s_export_op = &ext4_export_ops;
2741         sb->s_xattr = ext4_xattr_handlers;
2742 #ifdef CONFIG_QUOTA
2743         sb->s_qcop = &ext4_qctl_operations;
2744         sb->dq_op = &ext4_quota_operations;
2745 #endif
2746         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2747         mutex_init(&sbi->s_orphan_lock);
2748         mutex_init(&sbi->s_resize_lock);
2749
2750         sb->s_root = NULL;
2751
2752         needs_recovery = (es->s_last_orphan != 0 ||
2753                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2754                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2755
2756         /*
2757          * The first inode we look at is the journal inode.  Don't try
2758          * root first: it may be modified in the journal!
2759          */
2760         if (!test_opt(sb, NOLOAD) &&
2761             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2762                 if (ext4_load_journal(sb, es, journal_devnum))
2763                         goto failed_mount3;
2764         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2765               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2766                 ext4_msg(sb, KERN_ERR, "required journal recovery "
2767                        "suppressed and not mounted read-only");
2768                 goto failed_mount4;
2769         } else {
2770                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2771                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2772                 sbi->s_journal = NULL;
2773                 needs_recovery = 0;
2774                 goto no_journal;
2775         }
2776
2777         if (ext4_blocks_count(es) > 0xffffffffULL &&
2778             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2779                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2780                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
2781                 goto failed_mount4;
2782         }
2783
2784         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2785                 jbd2_journal_set_features(sbi->s_journal,
2786                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2787                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2788         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2789                 jbd2_journal_set_features(sbi->s_journal,
2790                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2791                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2792                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2793         } else {
2794                 jbd2_journal_clear_features(sbi->s_journal,
2795                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2796                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2797         }
2798
2799         /* We have now updated the journal if required, so we can
2800          * validate the data journaling mode. */
2801         switch (test_opt(sb, DATA_FLAGS)) {
2802         case 0:
2803                 /* No mode set, assume a default based on the journal
2804                  * capabilities: ORDERED_DATA if the journal can
2805                  * cope, else JOURNAL_DATA
2806                  */
2807                 if (jbd2_journal_check_available_features
2808                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2809                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2810                 else
2811                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2812                 break;
2813
2814         case EXT4_MOUNT_ORDERED_DATA:
2815         case EXT4_MOUNT_WRITEBACK_DATA:
2816                 if (!jbd2_journal_check_available_features
2817                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2818                         ext4_msg(sb, KERN_ERR, "Journal does not support "
2819                                "requested data journaling mode");
2820                         goto failed_mount4;
2821                 }
2822         default:
2823                 break;
2824         }
2825         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2826
2827 no_journal:
2828
2829         if (test_opt(sb, NOBH)) {
2830                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2831                         ext4_msg(sb, KERN_WARNING, "Ignoring nobh option - "
2832                                 "its supported only with writeback mode");
2833                         clear_opt(sbi->s_mount_opt, NOBH);
2834                 }
2835         }
2836         EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten");
2837         if (!EXT4_SB(sb)->dio_unwritten_wq) {
2838                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
2839                 goto failed_mount_wq;
2840         }
2841
2842         /*
2843          * The jbd2_journal_load will have done any necessary log recovery,
2844          * so we can safely mount the rest of the filesystem now.
2845          */
2846
2847         root = ext4_iget(sb, EXT4_ROOT_INO);
2848         if (IS_ERR(root)) {
2849                 ext4_msg(sb, KERN_ERR, "get root inode failed");
2850                 ret = PTR_ERR(root);
2851                 goto failed_mount4;
2852         }
2853         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2854                 iput(root);
2855                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
2856                 goto failed_mount4;
2857         }
2858         sb->s_root = d_alloc_root(root);
2859         if (!sb->s_root) {
2860                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
2861                 iput(root);
2862                 ret = -ENOMEM;
2863                 goto failed_mount4;
2864         }
2865
2866         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2867
2868         /* determine the minimum size of new large inodes, if present */
2869         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2870                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2871                                                      EXT4_GOOD_OLD_INODE_SIZE;
2872                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2873                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2874                         if (sbi->s_want_extra_isize <
2875                             le16_to_cpu(es->s_want_extra_isize))
2876                                 sbi->s_want_extra_isize =
2877                                         le16_to_cpu(es->s_want_extra_isize);
2878                         if (sbi->s_want_extra_isize <
2879                             le16_to_cpu(es->s_min_extra_isize))
2880                                 sbi->s_want_extra_isize =
2881                                         le16_to_cpu(es->s_min_extra_isize);
2882                 }
2883         }
2884         /* Check if enough inode space is available */
2885         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2886                                                         sbi->s_inode_size) {
2887                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2888                                                        EXT4_GOOD_OLD_INODE_SIZE;
2889                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
2890                          "available");
2891         }
2892
2893         if (test_opt(sb, DELALLOC) &&
2894             (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2895                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
2896                          "requested data journaling mode");
2897                 clear_opt(sbi->s_mount_opt, DELALLOC);
2898         }
2899
2900         err = ext4_setup_system_zone(sb);
2901         if (err) {
2902                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
2903                          "zone (%d)\n", err);
2904                 goto failed_mount4;
2905         }
2906
2907         ext4_ext_init(sb);
2908         err = ext4_mb_init(sb, needs_recovery);
2909         if (err) {
2910                 ext4_msg(sb, KERN_ERR, "failed to initalize mballoc (%d)",
2911                          err);
2912                 goto failed_mount4;
2913         }
2914
2915         sbi->s_kobj.kset = ext4_kset;
2916         init_completion(&sbi->s_kobj_unregister);
2917         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
2918                                    "%s", sb->s_id);
2919         if (err) {
2920                 ext4_mb_release(sb);
2921                 ext4_ext_release(sb);
2922                 goto failed_mount4;
2923         };
2924
2925         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2926         ext4_orphan_cleanup(sb, es);
2927         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2928         if (needs_recovery) {
2929                 ext4_msg(sb, KERN_INFO, "recovery complete");
2930                 ext4_mark_recovery_complete(sb, es);
2931         }
2932         if (EXT4_SB(sb)->s_journal) {
2933                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2934                         descr = " journalled data mode";
2935                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2936                         descr = " ordered data mode";
2937                 else
2938                         descr = " writeback data mode";
2939         } else
2940                 descr = "out journal";
2941
2942         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s", descr);
2943
2944         lock_kernel();
2945         return 0;
2946
2947 cantfind_ext4:
2948         if (!silent)
2949                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
2950         goto failed_mount;
2951
2952 failed_mount4:
2953         ext4_msg(sb, KERN_ERR, "mount failed");
2954         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
2955 failed_mount_wq:
2956         ext4_release_system_zone(sb);
2957         if (sbi->s_journal) {
2958                 jbd2_journal_destroy(sbi->s_journal);
2959                 sbi->s_journal = NULL;
2960         }
2961 failed_mount3:
2962         if (sbi->s_flex_groups) {
2963                 if (is_vmalloc_addr(sbi->s_flex_groups))
2964                         vfree(sbi->s_flex_groups);
2965                 else
2966                         kfree(sbi->s_flex_groups);
2967         }
2968         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2969         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2970         percpu_counter_destroy(&sbi->s_dirs_counter);
2971         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2972 failed_mount2:
2973         for (i = 0; i < db_count; i++)
2974                 brelse(sbi->s_group_desc[i]);
2975         kfree(sbi->s_group_desc);
2976 failed_mount:
2977         if (sbi->s_proc) {
2978                 remove_proc_entry(sb->s_id, ext4_proc_root);
2979         }
2980 #ifdef CONFIG_QUOTA
2981         for (i = 0; i < MAXQUOTAS; i++)
2982                 kfree(sbi->s_qf_names[i]);
2983 #endif
2984         ext4_blkdev_remove(sbi);
2985         brelse(bh);
2986 out_fail:
2987         sb->s_fs_info = NULL;
2988         kfree(sbi->s_blockgroup_lock);
2989         kfree(sbi);
2990         lock_kernel();
2991         return ret;
2992 }
2993
2994 /*
2995  * Setup any per-fs journal parameters now.  We'll do this both on
2996  * initial mount, once the journal has been initialised but before we've
2997  * done any recovery; and again on any subsequent remount.
2998  */
2999 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
3000 {
3001         struct ext4_sb_info *sbi = EXT4_SB(sb);
3002
3003         journal->j_commit_interval = sbi->s_commit_interval;
3004         journal->j_min_batch_time = sbi->s_min_batch_time;
3005         journal->j_max_batch_time = sbi->s_max_batch_time;
3006
3007         spin_lock(&journal->j_state_lock);
3008         if (test_opt(sb, BARRIER))
3009                 journal->j_flags |= JBD2_BARRIER;
3010         else
3011                 journal->j_flags &= ~JBD2_BARRIER;
3012         if (test_opt(sb, DATA_ERR_ABORT))
3013                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3014         else
3015                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3016         spin_unlock(&journal->j_state_lock);
3017 }
3018
3019 static journal_t *ext4_get_journal(struct super_block *sb,
3020                                    unsigned int journal_inum)
3021 {
3022         struct inode *journal_inode;
3023         journal_t *journal;
3024
3025         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3026
3027         /* First, test for the existence of a valid inode on disk.  Bad
3028          * things happen if we iget() an unused inode, as the subsequent
3029          * iput() will try to delete it. */
3030
3031         journal_inode = ext4_iget(sb, journal_inum);
3032         if (IS_ERR(journal_inode)) {
3033                 ext4_msg(sb, KERN_ERR, "no journal found");
3034                 return NULL;
3035         }
3036         if (!journal_inode->i_nlink) {
3037                 make_bad_inode(journal_inode);
3038                 iput(journal_inode);
3039                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3040                 return NULL;
3041         }
3042
3043         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3044                   journal_inode, journal_inode->i_size);
3045         if (!S_ISREG(journal_inode->i_mode)) {
3046                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3047                 iput(journal_inode);
3048                 return NULL;
3049         }
3050
3051         journal = jbd2_journal_init_inode(journal_inode);
3052         if (!journal) {
3053                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3054                 iput(journal_inode);
3055                 return NULL;
3056         }
3057         journal->j_private = sb;
3058         ext4_init_journal_params(sb, journal);
3059         return journal;
3060 }
3061
3062 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3063                                        dev_t j_dev)
3064 {
3065         struct buffer_head *bh;
3066         journal_t *journal;
3067         ext4_fsblk_t start;
3068         ext4_fsblk_t len;
3069         int hblock, blocksize;
3070         ext4_fsblk_t sb_block;
3071         unsigned long offset;
3072         struct ext4_super_block *es;
3073         struct block_device *bdev;
3074
3075         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3076
3077         bdev = ext4_blkdev_get(j_dev, sb);
3078         if (bdev == NULL)
3079                 return NULL;
3080
3081         if (bd_claim(bdev, sb)) {
3082                 ext4_msg(sb, KERN_ERR,
3083                         "failed to claim external journal device");
3084                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3085                 return NULL;
3086         }
3087
3088         blocksize = sb->s_blocksize;
3089         hblock = bdev_logical_block_size(bdev);
3090         if (blocksize < hblock) {
3091                 ext4_msg(sb, KERN_ERR,
3092                         "blocksize too small for journal device");
3093                 goto out_bdev;
3094         }
3095
3096         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3097         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3098         set_blocksize(bdev, blocksize);
3099         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3100                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3101                        "external journal");
3102                 goto out_bdev;
3103         }
3104
3105         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3106         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3107             !(le32_to_cpu(es->s_feature_incompat) &
3108               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3109                 ext4_msg(sb, KERN_ERR, "external journal has "
3110                                         "bad superblock");
3111                 brelse(bh);
3112                 goto out_bdev;
3113         }
3114
3115         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3116                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3117                 brelse(bh);
3118                 goto out_bdev;
3119         }
3120
3121         len = ext4_blocks_count(es);
3122         start = sb_block + 1;
3123         brelse(bh);     /* we're done with the superblock */
3124
3125         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3126                                         start, len, blocksize);
3127         if (!journal) {
3128                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3129                 goto out_bdev;
3130         }
3131         journal->j_private = sb;
3132         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3133         wait_on_buffer(journal->j_sb_buffer);
3134         if (!buffer_uptodate(journal->j_sb_buffer)) {
3135                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3136                 goto out_journal;
3137         }
3138         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3139                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3140                                         "user (unsupported) - %d",
3141                         be32_to_cpu(journal->j_superblock->s_nr_users));
3142                 goto out_journal;
3143         }
3144         EXT4_SB(sb)->journal_bdev = bdev;
3145         ext4_init_journal_params(sb, journal);
3146         return journal;
3147
3148 out_journal:
3149         jbd2_journal_destroy(journal);
3150 out_bdev:
3151         ext4_blkdev_put(bdev);
3152         return NULL;
3153 }
3154
3155 static int ext4_load_journal(struct super_block *sb,
3156                              struct ext4_super_block *es,
3157                              unsigned long journal_devnum)
3158 {
3159         journal_t *journal;
3160         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3161         dev_t journal_dev;
3162         int err = 0;
3163         int really_read_only;
3164
3165         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3166
3167         if (journal_devnum &&
3168             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3169                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3170                         "numbers have changed");
3171                 journal_dev = new_decode_dev(journal_devnum);
3172         } else
3173                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3174
3175         really_read_only = bdev_read_only(sb->s_bdev);
3176
3177         /*
3178          * Are we loading a blank journal or performing recovery after a
3179          * crash?  For recovery, we need to check in advance whether we
3180          * can get read-write access to the device.
3181          */
3182         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3183                 if (sb->s_flags & MS_RDONLY) {
3184                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3185                                         "required on readonly filesystem");
3186                         if (really_read_only) {
3187                                 ext4_msg(sb, KERN_ERR, "write access "
3188                                         "unavailable, cannot proceed");
3189                                 return -EROFS;
3190                         }
3191                         ext4_msg(sb, KERN_INFO, "write access will "
3192                                "be enabled during recovery");
3193                 }
3194         }
3195
3196         if (journal_inum && journal_dev) {
3197                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3198                        "and inode journals!");
3199                 return -EINVAL;
3200         }
3201
3202         if (journal_inum) {
3203                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3204                         return -EINVAL;
3205         } else {
3206                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3207                         return -EINVAL;
3208         }
3209
3210         if (!(journal->j_flags & JBD2_BARRIER))
3211                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3212
3213         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3214                 err = jbd2_journal_update_format(journal);
3215                 if (err)  {
3216                         ext4_msg(sb, KERN_ERR, "error updating journal");
3217                         jbd2_journal_destroy(journal);
3218                         return err;
3219                 }
3220         }
3221
3222         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3223                 err = jbd2_journal_wipe(journal, !really_read_only);
3224         if (!err)
3225                 err = jbd2_journal_load(journal);
3226
3227         if (err) {
3228                 ext4_msg(sb, KERN_ERR, "error loading journal");
3229                 jbd2_journal_destroy(journal);
3230                 return err;
3231         }
3232
3233         EXT4_SB(sb)->s_journal = journal;
3234         ext4_clear_journal_err(sb, es);
3235
3236         if (journal_devnum &&
3237             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3238                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3239
3240                 /* Make sure we flush the recovery flag to disk. */
3241                 ext4_commit_super(sb, 1);
3242         }
3243
3244         return 0;
3245 }
3246
3247 static int ext4_commit_super(struct super_block *sb, int sync)
3248 {
3249         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3250         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3251         int error = 0;
3252
3253         if (!sbh)
3254                 return error;
3255         if (buffer_write_io_error(sbh)) {
3256                 /*
3257                  * Oh, dear.  A previous attempt to write the
3258                  * superblock failed.  This could happen because the
3259                  * USB device was yanked out.  Or it could happen to
3260                  * be a transient write error and maybe the block will
3261                  * be remapped.  Nothing we can do but to retry the
3262                  * write and hope for the best.
3263                  */
3264                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3265                        "superblock detected");
3266                 clear_buffer_write_io_error(sbh);
3267                 set_buffer_uptodate(sbh);
3268         }
3269         /*
3270          * If the file system is mounted read-only, don't update the
3271          * superblock write time.  This avoids updating the superblock
3272          * write time when we are mounting the root file system
3273          * read/only but we need to replay the journal; at that point,
3274          * for people who are east of GMT and who make their clock
3275          * tick in localtime for Windows bug-for-bug compatibility,
3276          * the clock is set in the future, and this will cause e2fsck
3277          * to complain and force a full file system check.
3278          */
3279         if (!(sb->s_flags & MS_RDONLY))
3280                 es->s_wtime = cpu_to_le32(get_seconds());
3281         es->s_kbytes_written =
3282                 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written + 
3283                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3284                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
3285         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3286                                         &EXT4_SB(sb)->s_freeblocks_counter));
3287         es->s_free_inodes_count = cpu_to_le32(percpu_counter_sum_positive(
3288                                         &EXT4_SB(sb)->s_freeinodes_counter));
3289         sb->s_dirt = 0;
3290         BUFFER_TRACE(sbh, "marking dirty");
3291         mark_buffer_dirty(sbh);
3292         if (sync) {
3293                 error = sync_dirty_buffer(sbh);
3294                 if (error)
3295                         return error;
3296
3297                 error = buffer_write_io_error(sbh);
3298                 if (error) {
3299                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
3300                                "superblock");
3301                         clear_buffer_write_io_error(sbh);
3302                         set_buffer_uptodate(sbh);
3303                 }
3304         }
3305         return error;
3306 }
3307
3308 /*
3309  * Have we just finished recovery?  If so, and if we are mounting (or
3310  * remounting) the filesystem readonly, then we will end up with a
3311  * consistent fs on disk.  Record that fact.
3312  */
3313 static void ext4_mark_recovery_complete(struct super_block *sb,
3314                                         struct ext4_super_block *es)
3315 {
3316         journal_t *journal = EXT4_SB(sb)->s_journal;
3317
3318         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3319                 BUG_ON(journal != NULL);
3320                 return;
3321         }
3322         jbd2_journal_lock_updates(journal);
3323         if (jbd2_journal_flush(journal) < 0)
3324                 goto out;
3325
3326         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
3327             sb->s_flags & MS_RDONLY) {
3328                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3329                 ext4_commit_super(sb, 1);
3330         }
3331
3332 out:
3333         jbd2_journal_unlock_updates(journal);
3334 }
3335
3336 /*
3337  * If we are mounting (or read-write remounting) a filesystem whose journal
3338  * has recorded an error from a previous lifetime, move that error to the
3339  * main filesystem now.
3340  */
3341 static void ext4_clear_journal_err(struct super_block *sb,
3342                                    struct ext4_super_block *es)
3343 {
3344         journal_t *journal;
3345         int j_errno;
3346         const char *errstr;
3347
3348         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3349
3350         journal = EXT4_SB(sb)->s_journal;
3351
3352         /*
3353          * Now check for any error status which may have been recorded in the
3354          * journal by a prior ext4_error() or ext4_abort()
3355          */
3356
3357         j_errno = jbd2_journal_errno(journal);
3358         if (j_errno) {
3359                 char nbuf[16];
3360
3361                 errstr = ext4_decode_error(sb, j_errno, nbuf);
3362                 ext4_warning(sb, __func__, "Filesystem error recorded "
3363                              "from previous mount: %s", errstr);
3364                 ext4_warning(sb, __func__, "Marking fs in need of "
3365                              "filesystem check.");
3366
3367                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
3368                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
3369                 ext4_commit_super(sb, 1);
3370
3371                 jbd2_journal_clear_err(journal);
3372         }
3373 }
3374
3375 /*
3376  * Force the running and committing transactions to commit,
3377  * and wait on the commit.
3378  */
3379 int ext4_force_commit(struct super_block *sb)
3380 {
3381         journal_t *journal;
3382         int ret = 0;
3383
3384         if (sb->s_flags & MS_RDONLY)
3385                 return 0;
3386
3387         journal = EXT4_SB(sb)->s_journal;
3388         if (journal)
3389                 ret = ext4_journal_force_commit(journal);
3390
3391         return ret;
3392 }
3393
3394 static void ext4_write_super(struct super_block *sb)
3395 {
3396         lock_super(sb);
3397         ext4_commit_super(sb, 1);
3398         unlock_super(sb);
3399 }
3400
3401 static int ext4_sync_fs(struct super_block *sb, int wait)
3402 {
3403         int ret = 0;
3404         tid_t target;
3405         struct ext4_sb_info *sbi = EXT4_SB(sb);
3406
3407         trace_ext4_sync_fs(sb, wait);
3408         flush_workqueue(sbi->dio_unwritten_wq);
3409         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
3410                 if (wait)
3411                         jbd2_log_wait_commit(sbi->s_journal, target);
3412         }
3413         return ret;
3414 }
3415
3416 /*
3417  * LVM calls this function before a (read-only) snapshot is created.  This
3418  * gives us a chance to flush the journal completely and mark the fs clean.
3419  */
3420 static int ext4_freeze(struct super_block *sb)
3421 {
3422         int error = 0;
3423         journal_t *journal;
3424
3425         if (sb->s_flags & MS_RDONLY)
3426                 return 0;
3427
3428         journal = EXT4_SB(sb)->s_journal;
3429
3430         /* Now we set up the journal barrier. */
3431         jbd2_journal_lock_updates(journal);
3432
3433         /*
3434          * Don't clear the needs_recovery flag if we failed to flush
3435          * the journal.
3436          */
3437         error = jbd2_journal_flush(journal);
3438         if (error < 0) {
3439         out:
3440                 jbd2_journal_unlock_updates(journal);
3441                 return error;
3442         }
3443
3444         /* Journal blocked and flushed, clear needs_recovery flag. */
3445         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3446         error = ext4_commit_super(sb, 1);
3447         if (error)
3448                 goto out;
3449         return 0;
3450 }
3451
3452 /*
3453  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
3454  * flag here, even though the filesystem is not technically dirty yet.
3455  */
3456 static int ext4_unfreeze(struct super_block *sb)
3457 {
3458         if (sb->s_flags & MS_RDONLY)
3459                 return 0;
3460
3461         lock_super(sb);
3462         /* Reset the needs_recovery flag before the fs is unlocked. */
3463         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3464         ext4_commit_super(sb, 1);
3465         unlock_super(sb);
3466         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3467         return 0;
3468 }
3469
3470 static int ext4_remount(struct super_block *sb, int *flags, char *data)
3471 {
3472         struct ext4_super_block *es;
3473         struct ext4_sb_info *sbi = EXT4_SB(sb);
3474         ext4_fsblk_t n_blocks_count = 0;
3475         unsigned long old_sb_flags;
3476         struct ext4_mount_options old_opts;
3477         ext4_group_t g;
3478         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3479         int err;
3480 #ifdef CONFIG_QUOTA
3481         int i;
3482 #endif
3483
3484         lock_kernel();
3485
3486         /* Store the original options */
3487         lock_super(sb);
3488         old_sb_flags = sb->s_flags;
3489         old_opts.s_mount_opt = sbi->s_mount_opt;
3490         old_opts.s_resuid = sbi->s_resuid;
3491         old_opts.s_resgid = sbi->s_resgid;
3492         old_opts.s_commit_interval = sbi->s_commit_interval;
3493         old_opts.s_min_batch_time = sbi->s_min_batch_time;
3494         old_opts.s_max_batch_time = sbi->s_max_batch_time;
3495 #ifdef CONFIG_QUOTA
3496         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3497         for (i = 0; i < MAXQUOTAS; i++)
3498                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3499 #endif
3500         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
3501                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
3502
3503         /*
3504          * Allow the "check" option to be passed as a remount option.
3505          */
3506         if (!parse_options(data, sb, NULL, &journal_ioprio,
3507                            &n_blocks_count, 1)) {
3508                 err = -EINVAL;
3509                 goto restore_opts;
3510         }
3511
3512         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
3513                 ext4_abort(sb, __func__, "Abort forced by user");
3514
3515         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3516                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
3517
3518         es = sbi->s_es;
3519
3520         if (sbi->s_journal) {
3521                 ext4_init_journal_params(sb, sbi->s_journal);
3522                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3523         }
3524
3525         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3526                 n_blocks_count > ext4_blocks_count(es)) {
3527                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
3528                         err = -EROFS;
3529                         goto restore_opts;
3530                 }
3531
3532                 if (*flags & MS_RDONLY) {
3533                         /*
3534                          * First of all, the unconditional stuff we have to do
3535                          * to disable replay of the journal when we next remount
3536                          */
3537                         sb->s_flags |= MS_RDONLY;
3538
3539                         /*
3540                          * OK, test if we are remounting a valid rw partition
3541                          * readonly, and if so set the rdonly flag and then
3542                          * mark the partition as valid again.
3543                          */
3544                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3545                             (sbi->s_mount_state & EXT4_VALID_FS))
3546                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3547
3548                         if (sbi->s_journal)
3549                                 ext4_mark_recovery_complete(sb, es);
3550                 } else {
3551                         /* Make sure we can mount this feature set readwrite */
3552                         if (!ext4_feature_set_ok(sb, 0)) {
3553                                 err = -EROFS;
3554                                 goto restore_opts;
3555                         }
3556                         /*
3557                          * Make sure the group descriptor checksums
3558                          * are sane.  If they aren't, refuse to remount r/w.
3559                          */
3560                         for (g = 0; g < sbi->s_groups_count; g++) {
3561                                 struct ext4_group_desc *gdp =
3562                                         ext4_get_group_desc(sb, g, NULL);
3563
3564                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3565                                         ext4_msg(sb, KERN_ERR,
3566                "ext4_remount: Checksum for group %u failed (%u!=%u)",
3567                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3568                                                le16_to_cpu(gdp->bg_checksum));
3569                                         err = -EINVAL;
3570                                         goto restore_opts;
3571                                 }
3572                         }
3573
3574                         /*
3575                          * If we have an unprocessed orphan list hanging
3576                          * around from a previously readonly bdev mount,
3577                          * require a full umount/remount for now.
3578                          */
3579                         if (es->s_last_orphan) {
3580                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
3581                                        "remount RDWR because of unprocessed "
3582                                        "orphan inode list.  Please "
3583                                        "umount/remount instead");
3584                                 err = -EINVAL;
3585                                 goto restore_opts;
3586                         }
3587
3588                         /*
3589                          * Mounting a RDONLY partition read-write, so reread
3590                          * and store the current valid flag.  (It may have
3591                          * been changed by e2fsck since we originally mounted
3592                          * the partition.)
3593                          */
3594                         if (sbi->s_journal)
3595                                 ext4_clear_journal_err(sb, es);
3596                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3597                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3598                                 goto restore_opts;
3599                         if (!ext4_setup_super(sb, es, 0))
3600                                 sb->s_flags &= ~MS_RDONLY;
3601                 }
3602         }
3603         ext4_setup_system_zone(sb);
3604         if (sbi->s_journal == NULL)
3605                 ext4_commit_super(sb, 1);
3606
3607 #ifdef CONFIG_QUOTA
3608         /* Release old quota file names */
3609         for (i = 0; i < MAXQUOTAS; i++)
3610                 if (old_opts.s_qf_names[i] &&
3611                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3612                         kfree(old_opts.s_qf_names[i]);
3613 #endif
3614         unlock_super(sb);
3615         unlock_kernel();
3616         return 0;
3617
3618 restore_opts:
3619         sb->s_flags = old_sb_flags;
3620         sbi->s_mount_opt = old_opts.s_mount_opt;
3621         sbi->s_resuid = old_opts.s_resuid;
3622         sbi->s_resgid = old_opts.s_resgid;
3623         sbi->s_commit_interval = old_opts.s_commit_interval;
3624         sbi->s_min_batch_time = old_opts.s_min_batch_time;
3625         sbi->s_max_batch_time = old_opts.s_max_batch_time;
3626 #ifdef CONFIG_QUOTA
3627         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3628         for (i = 0; i < MAXQUOTAS; i++) {
3629                 if (sbi->s_qf_names[i] &&
3630                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3631                         kfree(sbi->s_qf_names[i]);
3632                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3633         }
3634 #endif
3635         unlock_super(sb);
3636         unlock_kernel();
3637         return err;
3638 }
3639
3640 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3641 {
3642         struct super_block *sb = dentry->d_sb;
3643         struct ext4_sb_info *sbi = EXT4_SB(sb);
3644         struct ext4_super_block *es = sbi->s_es;
3645         u64 fsid;
3646
3647         if (test_opt(sb, MINIX_DF)) {
3648                 sbi->s_overhead_last = 0;
3649         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3650                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3651                 ext4_fsblk_t overhead = 0;
3652
3653                 /*
3654                  * Compute the overhead (FS structures).  This is constant
3655                  * for a given filesystem unless the number of block groups
3656                  * changes so we cache the previous value until it does.
3657                  */
3658
3659                 /*
3660                  * All of the blocks before first_data_block are
3661                  * overhead
3662                  */
3663                 overhead = le32_to_cpu(es->s_first_data_block);
3664
3665                 /*
3666                  * Add the overhead attributed to the superblock and
3667                  * block group descriptors.  If the sparse superblocks
3668                  * feature is turned on, then not all groups have this.
3669                  */
3670                 for (i = 0; i < ngroups; i++) {
3671                         overhead += ext4_bg_has_super(sb, i) +
3672                                 ext4_bg_num_gdb(sb, i);
3673                         cond_resched();
3674                 }
3675
3676                 /*
3677                  * Every block group has an inode bitmap, a block
3678                  * bitmap, and an inode table.
3679                  */
3680                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3681                 sbi->s_overhead_last = overhead;
3682                 smp_wmb();
3683                 sbi->s_blocks_last = ext4_blocks_count(es);
3684         }
3685
3686         buf->f_type = EXT4_SUPER_MAGIC;
3687         buf->f_bsize = sb->s_blocksize;
3688         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3689         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3690                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3691         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3692         if (buf->f_bfree < ext4_r_blocks_count(es))
3693                 buf->f_bavail = 0;
3694         buf->f_files = le32_to_cpu(es->s_inodes_count);
3695         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3696         buf->f_namelen = EXT4_NAME_LEN;
3697         fsid = le64_to_cpup((void *)es->s_uuid) ^
3698                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3699         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3700         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3701
3702         return 0;
3703 }
3704
3705 /* Helper function for writing quotas on sync - we need to start transaction
3706  * before quota file is locked for write. Otherwise the are possible deadlocks:
3707  * Process 1                         Process 2
3708  * ext4_create()                     quota_sync()
3709  *   jbd2_journal_start()                  write_dquot()
3710  *   vfs_dq_init()                         down(dqio_mutex)
3711  *     down(dqio_mutex)                    jbd2_journal_start()
3712  *
3713  */
3714
3715 #ifdef CONFIG_QUOTA
3716
3717 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3718 {
3719         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3720 }
3721
3722 static int ext4_write_dquot(struct dquot *dquot)
3723 {
3724         int ret, err;
3725         handle_t *handle;
3726         struct inode *inode;
3727
3728         inode = dquot_to_inode(dquot);
3729         handle = ext4_journal_start(inode,
3730                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3731         if (IS_ERR(handle))
3732                 return PTR_ERR(handle);
3733         ret = dquot_commit(dquot);
3734         err = ext4_journal_stop(handle);
3735         if (!ret)
3736                 ret = err;
3737         return ret;
3738 }
3739
3740 static int ext4_acquire_dquot(struct dquot *dquot)
3741 {
3742         int ret, err;
3743         handle_t *handle;
3744
3745         handle = ext4_journal_start(dquot_to_inode(dquot),
3746                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3747         if (IS_ERR(handle))
3748                 return PTR_ERR(handle);
3749         ret = dquot_acquire(dquot);
3750         err = ext4_journal_stop(handle);
3751         if (!ret)
3752                 ret = err;
3753         return ret;
3754 }
3755
3756 static int ext4_release_dquot(struct dquot *dquot)
3757 {
3758         int ret, err;
3759         handle_t *handle;
3760
3761         handle = ext4_journal_start(dquot_to_inode(dquot),
3762                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3763         if (IS_ERR(handle)) {
3764                 /* Release dquot anyway to avoid endless cycle in dqput() */
3765                 dquot_release(dquot);
3766                 return PTR_ERR(handle);
3767         }
3768         ret = dquot_release(dquot);
3769         err = ext4_journal_stop(handle);
3770         if (!ret)
3771                 ret = err;
3772         return ret;
3773 }
3774
3775 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3776 {
3777         /* Are we journaling quotas? */
3778         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3779             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3780                 dquot_mark_dquot_dirty(dquot);
3781                 return ext4_write_dquot(dquot);
3782         } else {
3783                 return dquot_mark_dquot_dirty(dquot);
3784         }
3785 }
3786
3787 static int ext4_write_info(struct super_block *sb, int type)
3788 {
3789         int ret, err;
3790         handle_t *handle;
3791
3792         /* Data block + inode block */
3793         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3794         if (IS_ERR(handle))
3795                 return PTR_ERR(handle);
3796         ret = dquot_commit_info(sb, type);
3797         err = ext4_journal_stop(handle);
3798         if (!ret)
3799                 ret = err;
3800         return ret;
3801 }
3802
3803 /*
3804  * Turn on quotas during mount time - we need to find
3805  * the quota file and such...
3806  */
3807 static int ext4_quota_on_mount(struct super_block *sb, int type)
3808 {
3809         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3810                                   EXT4_SB(sb)->s_jquota_fmt, type);
3811 }
3812
3813 /*
3814  * Standard function to be called on quota_on
3815  */
3816 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3817                          char *name, int remount)
3818 {
3819         int err;
3820         struct path path;
3821
3822         if (!test_opt(sb, QUOTA))
3823                 return -EINVAL;
3824         /* When remounting, no checks are needed and in fact, name is NULL */
3825         if (remount)
3826                 return vfs_quota_on(sb, type, format_id, name, remount);
3827
3828         err = kern_path(name, LOOKUP_FOLLOW, &path);
3829         if (err)
3830                 return err;
3831
3832         /* Quotafile not on the same filesystem? */
3833         if (path.mnt->mnt_sb != sb) {
3834                 path_put(&path);
3835                 return -EXDEV;
3836         }
3837         /* Journaling quota? */
3838         if (EXT4_SB(sb)->s_qf_names[type]) {
3839                 /* Quotafile not in fs root? */
3840                 if (path.dentry->d_parent != sb->s_root)
3841                         ext4_msg(sb, KERN_WARNING,
3842                                 "Quota file not on filesystem root. "
3843                                 "Journaled quota will not work");
3844         }
3845
3846         /*
3847          * When we journal data on quota file, we have to flush journal to see
3848          * all updates to the file when we bypass pagecache...
3849          */
3850         if (EXT4_SB(sb)->s_journal &&
3851             ext4_should_journal_data(path.dentry->d_inode)) {
3852                 /*
3853                  * We don't need to lock updates but journal_flush() could
3854                  * otherwise be livelocked...
3855                  */
3856                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3857                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3858                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3859                 if (err) {
3860                         path_put(&path);
3861                         return err;
3862                 }
3863         }
3864
3865         err = vfs_quota_on_path(sb, type, format_id, &path);
3866         path_put(&path);
3867         return err;
3868 }
3869
3870 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3871  * acquiring the locks... As quota files are never truncated and quota code
3872  * itself serializes the operations (and noone else should touch the files)
3873  * we don't have to be afraid of races */
3874 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3875                                size_t len, loff_t off)
3876 {
3877         struct inode *inode = sb_dqopt(sb)->files[type];
3878         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3879         int err = 0;
3880         int offset = off & (sb->s_blocksize - 1);
3881         int tocopy;
3882         size_t toread;
3883         struct buffer_head *bh;
3884         loff_t i_size = i_size_read(inode);
3885
3886         if (off > i_size)
3887                 return 0;
3888         if (off+len > i_size)
3889                 len = i_size-off;
3890         toread = len;
3891         while (toread > 0) {
3892                 tocopy = sb->s_blocksize - offset < toread ?
3893                                 sb->s_blocksize - offset : toread;
3894                 bh = ext4_bread(NULL, inode, blk, 0, &err);
3895                 if (err)
3896                         return err;
3897                 if (!bh)        /* A hole? */
3898                         memset(data, 0, tocopy);
3899                 else
3900                         memcpy(data, bh->b_data+offset, tocopy);
3901                 brelse(bh);
3902                 offset = 0;
3903                 toread -= tocopy;
3904                 data += tocopy;
3905                 blk++;
3906         }
3907         return len;
3908 }
3909
3910 /* Write to quotafile (we know the transaction is already started and has
3911  * enough credits) */
3912 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3913                                 const char *data, size_t len, loff_t off)
3914 {
3915         struct inode *inode = sb_dqopt(sb)->files[type];
3916         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3917         int err = 0;
3918         int offset = off & (sb->s_blocksize - 1);
3919         int tocopy;
3920         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3921         size_t towrite = len;
3922         struct buffer_head *bh;
3923         handle_t *handle = journal_current_handle();
3924
3925         if (EXT4_SB(sb)->s_journal && !handle) {
3926                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
3927                         " cancelled because transaction is not started",
3928                         (unsigned long long)off, (unsigned long long)len);
3929                 return -EIO;
3930         }
3931         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3932         while (towrite > 0) {
3933                 tocopy = sb->s_blocksize - offset < towrite ?
3934                                 sb->s_blocksize - offset : towrite;
3935                 bh = ext4_bread(handle, inode, blk, 1, &err);
3936                 if (!bh)
3937                         goto out;
3938                 if (journal_quota) {
3939                         err = ext4_journal_get_write_access(handle, bh);
3940                         if (err) {
3941                                 brelse(bh);
3942                                 goto out;
3943                         }
3944                 }
3945                 lock_buffer(bh);
3946                 memcpy(bh->b_data+offset, data, tocopy);
3947                 flush_dcache_page(bh->b_page);
3948                 unlock_buffer(bh);
3949                 if (journal_quota)
3950                         err = ext4_handle_dirty_metadata(handle, NULL, bh);
3951                 else {
3952                         /* Always do at least ordered writes for quotas */
3953                         err = ext4_jbd2_file_inode(handle, inode);
3954                         mark_buffer_dirty(bh);
3955                 }
3956                 brelse(bh);
3957                 if (err)
3958                         goto out;
3959                 offset = 0;
3960                 towrite -= tocopy;
3961                 data += tocopy;
3962                 blk++;
3963         }
3964 out:
3965         if (len == towrite) {
3966                 mutex_unlock(&inode->i_mutex);
3967                 return err;
3968         }
3969         if (inode->i_size < off+len-towrite) {
3970                 i_size_write(inode, off+len-towrite);
3971                 EXT4_I(inode)->i_disksize = inode->i_size;
3972         }
3973         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3974         ext4_mark_inode_dirty(handle, inode);
3975         mutex_unlock(&inode->i_mutex);
3976         return len - towrite;
3977 }
3978
3979 #endif
3980
3981 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
3982                        const char *dev_name, void *data, struct vfsmount *mnt)
3983 {
3984         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
3985 }
3986
3987 #if !defined(CONTIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
3988 static struct file_system_type ext2_fs_type = {
3989         .owner          = THIS_MODULE,
3990         .name           = "ext2",
3991         .get_sb         = ext4_get_sb,
3992         .kill_sb        = kill_block_super,
3993         .fs_flags       = FS_REQUIRES_DEV,
3994 };
3995
3996 static inline void register_as_ext2(void)
3997 {
3998         int err = register_filesystem(&ext2_fs_type);
3999         if (err)
4000                 printk(KERN_WARNING
4001                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
4002 }
4003
4004 static inline void unregister_as_ext2(void)
4005 {
4006         unregister_filesystem(&ext2_fs_type);
4007 }
4008 MODULE_ALIAS("ext2");
4009 #else
4010 static inline void register_as_ext2(void) { }
4011 static inline void unregister_as_ext2(void) { }
4012 #endif
4013
4014 #if !defined(CONTIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4015 static struct file_system_type ext3_fs_type = {
4016         .owner          = THIS_MODULE,
4017         .name           = "ext3",
4018         .get_sb         = ext4_get_sb,
4019         .kill_sb        = kill_block_super,
4020         .fs_flags       = FS_REQUIRES_DEV,
4021 };
4022
4023 static inline void register_as_ext3(void)
4024 {
4025         int err = register_filesystem(&ext3_fs_type);
4026         if (err)
4027                 printk(KERN_WARNING
4028                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
4029 }
4030
4031 static inline void unregister_as_ext3(void)
4032 {
4033         unregister_filesystem(&ext3_fs_type);
4034 }
4035 MODULE_ALIAS("ext3");
4036 #else
4037 static inline void register_as_ext3(void) { }
4038 static inline void unregister_as_ext3(void) { }
4039 #endif
4040
4041 static struct file_system_type ext4_fs_type = {
4042         .owner          = THIS_MODULE,
4043         .name           = "ext4",
4044         .get_sb         = ext4_get_sb,
4045         .kill_sb        = kill_block_super,
4046         .fs_flags       = FS_REQUIRES_DEV,
4047 };
4048
4049 static int __init init_ext4_fs(void)
4050 {
4051         int err;
4052
4053         err = init_ext4_system_zone();
4054         if (err)
4055                 return err;
4056         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
4057         if (!ext4_kset)
4058                 goto out4;
4059         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
4060         err = init_ext4_mballoc();
4061         if (err)
4062                 goto out3;
4063
4064         err = init_ext4_xattr();
4065         if (err)
4066                 goto out2;
4067         err = init_inodecache();
4068         if (err)
4069                 goto out1;
4070         register_as_ext2();
4071         register_as_ext3();
4072         err = register_filesystem(&ext4_fs_type);
4073         if (err)
4074                 goto out;
4075         return 0;
4076 out:
4077         unregister_as_ext2();
4078         unregister_as_ext3();
4079         destroy_inodecache();
4080 out1:
4081         exit_ext4_xattr();
4082 out2:
4083         exit_ext4_mballoc();
4084 out3:
4085         remove_proc_entry("fs/ext4", NULL);
4086         kset_unregister(ext4_kset);
4087 out4:
4088         exit_ext4_system_zone();
4089         return err;
4090 }
4091
4092 static void __exit exit_ext4_fs(void)
4093 {
4094         unregister_as_ext2();
4095         unregister_as_ext3();
4096         unregister_filesystem(&ext4_fs_type);
4097         destroy_inodecache();
4098         exit_ext4_xattr();
4099         exit_ext4_mballoc();
4100         remove_proc_entry("fs/ext4", NULL);
4101         kset_unregister(ext4_kset);
4102         exit_ext4_system_zone();
4103 }
4104
4105 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4106 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4107 MODULE_LICENSE("GPL");
4108 module_init(init_ext4_fs)
4109 module_exit(exit_ext4_fs)