Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux...
[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         INIT_LIST_HEAD(&ei->i_aio_dio_complete_list);
708         ei->cur_aio_dio = NULL;
709         ei->i_sync_tid = 0;
710         ei->i_datasync_tid = 0;
711
712         return &ei->vfs_inode;
713 }
714
715 static void ext4_destroy_inode(struct inode *inode)
716 {
717         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
718                 ext4_msg(inode->i_sb, KERN_ERR,
719                          "Inode %lu (%p): orphan list check failed!",
720                          inode->i_ino, EXT4_I(inode));
721                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
722                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
723                                 true);
724                 dump_stack();
725         }
726         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
727 }
728
729 static void init_once(void *foo)
730 {
731         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
732
733         INIT_LIST_HEAD(&ei->i_orphan);
734 #ifdef CONFIG_EXT4_FS_XATTR
735         init_rwsem(&ei->xattr_sem);
736 #endif
737         init_rwsem(&ei->i_data_sem);
738         inode_init_once(&ei->vfs_inode);
739 }
740
741 static int init_inodecache(void)
742 {
743         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
744                                              sizeof(struct ext4_inode_info),
745                                              0, (SLAB_RECLAIM_ACCOUNT|
746                                                 SLAB_MEM_SPREAD),
747                                              init_once);
748         if (ext4_inode_cachep == NULL)
749                 return -ENOMEM;
750         return 0;
751 }
752
753 static void destroy_inodecache(void)
754 {
755         kmem_cache_destroy(ext4_inode_cachep);
756 }
757
758 static void ext4_clear_inode(struct inode *inode)
759 {
760         ext4_discard_preallocations(inode);
761         if (EXT4_JOURNAL(inode))
762                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
763                                        &EXT4_I(inode)->jinode);
764 }
765
766 static inline void ext4_show_quota_options(struct seq_file *seq,
767                                            struct super_block *sb)
768 {
769 #if defined(CONFIG_QUOTA)
770         struct ext4_sb_info *sbi = EXT4_SB(sb);
771
772         if (sbi->s_jquota_fmt) {
773                 char *fmtname = "";
774
775                 switch (sbi->s_jquota_fmt) {
776                 case QFMT_VFS_OLD:
777                         fmtname = "vfsold";
778                         break;
779                 case QFMT_VFS_V0:
780                         fmtname = "vfsv0";
781                         break;
782                 case QFMT_VFS_V1:
783                         fmtname = "vfsv1";
784                         break;
785                 }
786                 seq_printf(seq, ",jqfmt=%s", fmtname);
787         }
788
789         if (sbi->s_qf_names[USRQUOTA])
790                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
791
792         if (sbi->s_qf_names[GRPQUOTA])
793                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
794
795         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
796                 seq_puts(seq, ",usrquota");
797
798         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
799                 seq_puts(seq, ",grpquota");
800 #endif
801 }
802
803 /*
804  * Show an option if
805  *  - it's set to a non-default value OR
806  *  - if the per-sb default is different from the global default
807  */
808 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
809 {
810         int def_errors;
811         unsigned long def_mount_opts;
812         struct super_block *sb = vfs->mnt_sb;
813         struct ext4_sb_info *sbi = EXT4_SB(sb);
814         struct ext4_super_block *es = sbi->s_es;
815
816         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
817         def_errors     = le16_to_cpu(es->s_errors);
818
819         if (sbi->s_sb_block != 1)
820                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
821         if (test_opt(sb, MINIX_DF))
822                 seq_puts(seq, ",minixdf");
823         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
824                 seq_puts(seq, ",grpid");
825         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
826                 seq_puts(seq, ",nogrpid");
827         if (sbi->s_resuid != EXT4_DEF_RESUID ||
828             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
829                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
830         }
831         if (sbi->s_resgid != EXT4_DEF_RESGID ||
832             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
833                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
834         }
835         if (test_opt(sb, ERRORS_RO)) {
836                 if (def_errors == EXT4_ERRORS_PANIC ||
837                     def_errors == EXT4_ERRORS_CONTINUE) {
838                         seq_puts(seq, ",errors=remount-ro");
839                 }
840         }
841         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
842                 seq_puts(seq, ",errors=continue");
843         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
844                 seq_puts(seq, ",errors=panic");
845         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
846                 seq_puts(seq, ",nouid32");
847         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
848                 seq_puts(seq, ",debug");
849         if (test_opt(sb, OLDALLOC))
850                 seq_puts(seq, ",oldalloc");
851 #ifdef CONFIG_EXT4_FS_XATTR
852         if (test_opt(sb, XATTR_USER) &&
853                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
854                 seq_puts(seq, ",user_xattr");
855         if (!test_opt(sb, XATTR_USER) &&
856             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
857                 seq_puts(seq, ",nouser_xattr");
858         }
859 #endif
860 #ifdef CONFIG_EXT4_FS_POSIX_ACL
861         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
862                 seq_puts(seq, ",acl");
863         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
864                 seq_puts(seq, ",noacl");
865 #endif
866         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
867                 seq_printf(seq, ",commit=%u",
868                            (unsigned) (sbi->s_commit_interval / HZ));
869         }
870         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
871                 seq_printf(seq, ",min_batch_time=%u",
872                            (unsigned) sbi->s_min_batch_time);
873         }
874         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
875                 seq_printf(seq, ",max_batch_time=%u",
876                            (unsigned) sbi->s_min_batch_time);
877         }
878
879         /*
880          * We're changing the default of barrier mount option, so
881          * let's always display its mount state so it's clear what its
882          * status is.
883          */
884         seq_puts(seq, ",barrier=");
885         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
886         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
887                 seq_puts(seq, ",journal_async_commit");
888         if (test_opt(sb, NOBH))
889                 seq_puts(seq, ",nobh");
890         if (test_opt(sb, I_VERSION))
891                 seq_puts(seq, ",i_version");
892         if (!test_opt(sb, DELALLOC))
893                 seq_puts(seq, ",nodelalloc");
894
895
896         if (sbi->s_stripe)
897                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
898         /*
899          * journal mode get enabled in different ways
900          * So just print the value even if we didn't specify it
901          */
902         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
903                 seq_puts(seq, ",data=journal");
904         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
905                 seq_puts(seq, ",data=ordered");
906         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
907                 seq_puts(seq, ",data=writeback");
908
909         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
910                 seq_printf(seq, ",inode_readahead_blks=%u",
911                            sbi->s_inode_readahead_blks);
912
913         if (test_opt(sb, DATA_ERR_ABORT))
914                 seq_puts(seq, ",data_err=abort");
915
916         if (test_opt(sb, NO_AUTO_DA_ALLOC))
917                 seq_puts(seq, ",noauto_da_alloc");
918
919         if (test_opt(sb, DISCARD))
920                 seq_puts(seq, ",discard");
921
922         if (test_opt(sb, NOLOAD))
923                 seq_puts(seq, ",norecovery");
924
925         ext4_show_quota_options(seq, sb);
926
927         return 0;
928 }
929
930 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
931                                         u64 ino, u32 generation)
932 {
933         struct inode *inode;
934
935         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
936                 return ERR_PTR(-ESTALE);
937         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
938                 return ERR_PTR(-ESTALE);
939
940         /* iget isn't really right if the inode is currently unallocated!!
941          *
942          * ext4_read_inode will return a bad_inode if the inode had been
943          * deleted, so we should be safe.
944          *
945          * Currently we don't know the generation for parent directory, so
946          * a generation of 0 means "accept any"
947          */
948         inode = ext4_iget(sb, ino);
949         if (IS_ERR(inode))
950                 return ERR_CAST(inode);
951         if (generation && inode->i_generation != generation) {
952                 iput(inode);
953                 return ERR_PTR(-ESTALE);
954         }
955
956         return inode;
957 }
958
959 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
960                                         int fh_len, int fh_type)
961 {
962         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
963                                     ext4_nfs_get_inode);
964 }
965
966 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
967                                         int fh_len, int fh_type)
968 {
969         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
970                                     ext4_nfs_get_inode);
971 }
972
973 /*
974  * Try to release metadata pages (indirect blocks, directories) which are
975  * mapped via the block device.  Since these pages could have journal heads
976  * which would prevent try_to_free_buffers() from freeing them, we must use
977  * jbd2 layer's try_to_free_buffers() function to release them.
978  */
979 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
980                                  gfp_t wait)
981 {
982         journal_t *journal = EXT4_SB(sb)->s_journal;
983
984         WARN_ON(PageChecked(page));
985         if (!page_has_buffers(page))
986                 return 0;
987         if (journal)
988                 return jbd2_journal_try_to_free_buffers(journal, page,
989                                                         wait & ~__GFP_WAIT);
990         return try_to_free_buffers(page);
991 }
992
993 #ifdef CONFIG_QUOTA
994 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
995 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
996
997 static int ext4_write_dquot(struct dquot *dquot);
998 static int ext4_acquire_dquot(struct dquot *dquot);
999 static int ext4_release_dquot(struct dquot *dquot);
1000 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1001 static int ext4_write_info(struct super_block *sb, int type);
1002 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1003                                 char *path, int remount);
1004 static int ext4_quota_on_mount(struct super_block *sb, int type);
1005 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1006                                size_t len, loff_t off);
1007 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1008                                 const char *data, size_t len, loff_t off);
1009
1010 static const struct dquot_operations ext4_quota_operations = {
1011         .initialize     = dquot_initialize,
1012         .drop           = dquot_drop,
1013         .alloc_space    = dquot_alloc_space,
1014         .reserve_space  = dquot_reserve_space,
1015         .claim_space    = dquot_claim_space,
1016         .release_rsv    = dquot_release_reserved_space,
1017         .get_reserved_space = ext4_get_reserved_space,
1018         .alloc_inode    = dquot_alloc_inode,
1019         .free_space     = dquot_free_space,
1020         .free_inode     = dquot_free_inode,
1021         .transfer       = dquot_transfer,
1022         .write_dquot    = ext4_write_dquot,
1023         .acquire_dquot  = ext4_acquire_dquot,
1024         .release_dquot  = ext4_release_dquot,
1025         .mark_dirty     = ext4_mark_dquot_dirty,
1026         .write_info     = ext4_write_info,
1027         .alloc_dquot    = dquot_alloc,
1028         .destroy_dquot  = dquot_destroy,
1029 };
1030
1031 static const struct quotactl_ops ext4_qctl_operations = {
1032         .quota_on       = ext4_quota_on,
1033         .quota_off      = vfs_quota_off,
1034         .quota_sync     = vfs_quota_sync,
1035         .get_info       = vfs_get_dqinfo,
1036         .set_info       = vfs_set_dqinfo,
1037         .get_dqblk      = vfs_get_dqblk,
1038         .set_dqblk      = vfs_set_dqblk
1039 };
1040 #endif
1041
1042 static const struct super_operations ext4_sops = {
1043         .alloc_inode    = ext4_alloc_inode,
1044         .destroy_inode  = ext4_destroy_inode,
1045         .write_inode    = ext4_write_inode,
1046         .dirty_inode    = ext4_dirty_inode,
1047         .delete_inode   = ext4_delete_inode,
1048         .put_super      = ext4_put_super,
1049         .sync_fs        = ext4_sync_fs,
1050         .freeze_fs      = ext4_freeze,
1051         .unfreeze_fs    = ext4_unfreeze,
1052         .statfs         = ext4_statfs,
1053         .remount_fs     = ext4_remount,
1054         .clear_inode    = ext4_clear_inode,
1055         .show_options   = ext4_show_options,
1056 #ifdef CONFIG_QUOTA
1057         .quota_read     = ext4_quota_read,
1058         .quota_write    = ext4_quota_write,
1059 #endif
1060         .bdev_try_to_free_page = bdev_try_to_free_page,
1061 };
1062
1063 static const struct super_operations ext4_nojournal_sops = {
1064         .alloc_inode    = ext4_alloc_inode,
1065         .destroy_inode  = ext4_destroy_inode,
1066         .write_inode    = ext4_write_inode,
1067         .dirty_inode    = ext4_dirty_inode,
1068         .delete_inode   = ext4_delete_inode,
1069         .write_super    = ext4_write_super,
1070         .put_super      = ext4_put_super,
1071         .statfs         = ext4_statfs,
1072         .remount_fs     = ext4_remount,
1073         .clear_inode    = ext4_clear_inode,
1074         .show_options   = ext4_show_options,
1075 #ifdef CONFIG_QUOTA
1076         .quota_read     = ext4_quota_read,
1077         .quota_write    = ext4_quota_write,
1078 #endif
1079         .bdev_try_to_free_page = bdev_try_to_free_page,
1080 };
1081
1082 static const struct export_operations ext4_export_ops = {
1083         .fh_to_dentry = ext4_fh_to_dentry,
1084         .fh_to_parent = ext4_fh_to_parent,
1085         .get_parent = ext4_get_parent,
1086 };
1087
1088 enum {
1089         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1090         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1091         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1092         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1093         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1094         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1095         Opt_journal_update, Opt_journal_dev,
1096         Opt_journal_checksum, Opt_journal_async_commit,
1097         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1098         Opt_data_err_abort, Opt_data_err_ignore,
1099         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1100         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1101         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1102         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1103         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1104         Opt_block_validity, Opt_noblock_validity,
1105         Opt_inode_readahead_blks, Opt_journal_ioprio,
1106         Opt_discard, Opt_nodiscard,
1107 };
1108
1109 static const match_table_t tokens = {
1110         {Opt_bsd_df, "bsddf"},
1111         {Opt_minix_df, "minixdf"},
1112         {Opt_grpid, "grpid"},
1113         {Opt_grpid, "bsdgroups"},
1114         {Opt_nogrpid, "nogrpid"},
1115         {Opt_nogrpid, "sysvgroups"},
1116         {Opt_resgid, "resgid=%u"},
1117         {Opt_resuid, "resuid=%u"},
1118         {Opt_sb, "sb=%u"},
1119         {Opt_err_cont, "errors=continue"},
1120         {Opt_err_panic, "errors=panic"},
1121         {Opt_err_ro, "errors=remount-ro"},
1122         {Opt_nouid32, "nouid32"},
1123         {Opt_debug, "debug"},
1124         {Opt_oldalloc, "oldalloc"},
1125         {Opt_orlov, "orlov"},
1126         {Opt_user_xattr, "user_xattr"},
1127         {Opt_nouser_xattr, "nouser_xattr"},
1128         {Opt_acl, "acl"},
1129         {Opt_noacl, "noacl"},
1130         {Opt_noload, "noload"},
1131         {Opt_noload, "norecovery"},
1132         {Opt_nobh, "nobh"},
1133         {Opt_bh, "bh"},
1134         {Opt_commit, "commit=%u"},
1135         {Opt_min_batch_time, "min_batch_time=%u"},
1136         {Opt_max_batch_time, "max_batch_time=%u"},
1137         {Opt_journal_update, "journal=update"},
1138         {Opt_journal_dev, "journal_dev=%u"},
1139         {Opt_journal_checksum, "journal_checksum"},
1140         {Opt_journal_async_commit, "journal_async_commit"},
1141         {Opt_abort, "abort"},
1142         {Opt_data_journal, "data=journal"},
1143         {Opt_data_ordered, "data=ordered"},
1144         {Opt_data_writeback, "data=writeback"},
1145         {Opt_data_err_abort, "data_err=abort"},
1146         {Opt_data_err_ignore, "data_err=ignore"},
1147         {Opt_offusrjquota, "usrjquota="},
1148         {Opt_usrjquota, "usrjquota=%s"},
1149         {Opt_offgrpjquota, "grpjquota="},
1150         {Opt_grpjquota, "grpjquota=%s"},
1151         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1152         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1153         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1154         {Opt_grpquota, "grpquota"},
1155         {Opt_noquota, "noquota"},
1156         {Opt_quota, "quota"},
1157         {Opt_usrquota, "usrquota"},
1158         {Opt_barrier, "barrier=%u"},
1159         {Opt_barrier, "barrier"},
1160         {Opt_nobarrier, "nobarrier"},
1161         {Opt_i_version, "i_version"},
1162         {Opt_stripe, "stripe=%u"},
1163         {Opt_resize, "resize"},
1164         {Opt_delalloc, "delalloc"},
1165         {Opt_nodelalloc, "nodelalloc"},
1166         {Opt_block_validity, "block_validity"},
1167         {Opt_noblock_validity, "noblock_validity"},
1168         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1169         {Opt_journal_ioprio, "journal_ioprio=%u"},
1170         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1171         {Opt_auto_da_alloc, "auto_da_alloc"},
1172         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1173         {Opt_discard, "discard"},
1174         {Opt_nodiscard, "nodiscard"},
1175         {Opt_err, NULL},
1176 };
1177
1178 static ext4_fsblk_t get_sb_block(void **data)
1179 {
1180         ext4_fsblk_t    sb_block;
1181         char            *options = (char *) *data;
1182
1183         if (!options || strncmp(options, "sb=", 3) != 0)
1184                 return 1;       /* Default location */
1185
1186         options += 3;
1187         /* TODO: use simple_strtoll with >32bit ext4 */
1188         sb_block = simple_strtoul(options, &options, 0);
1189         if (*options && *options != ',') {
1190                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1191                        (char *) *data);
1192                 return 1;
1193         }
1194         if (*options == ',')
1195                 options++;
1196         *data = (void *) options;
1197
1198         return sb_block;
1199 }
1200
1201 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1202
1203 static int parse_options(char *options, struct super_block *sb,
1204                          unsigned long *journal_devnum,
1205                          unsigned int *journal_ioprio,
1206                          ext4_fsblk_t *n_blocks_count, int is_remount)
1207 {
1208         struct ext4_sb_info *sbi = EXT4_SB(sb);
1209         char *p;
1210         substring_t args[MAX_OPT_ARGS];
1211         int data_opt = 0;
1212         int option;
1213 #ifdef CONFIG_QUOTA
1214         int qtype, qfmt;
1215         char *qname;
1216 #endif
1217
1218         if (!options)
1219                 return 1;
1220
1221         while ((p = strsep(&options, ",")) != NULL) {
1222                 int token;
1223                 if (!*p)
1224                         continue;
1225
1226                 token = match_token(p, tokens, args);
1227                 switch (token) {
1228                 case Opt_bsd_df:
1229                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1230                         break;
1231                 case Opt_minix_df:
1232                         set_opt(sbi->s_mount_opt, MINIX_DF);
1233                         break;
1234                 case Opt_grpid:
1235                         set_opt(sbi->s_mount_opt, GRPID);
1236                         break;
1237                 case Opt_nogrpid:
1238                         clear_opt(sbi->s_mount_opt, GRPID);
1239                         break;
1240                 case Opt_resuid:
1241                         if (match_int(&args[0], &option))
1242                                 return 0;
1243                         sbi->s_resuid = option;
1244                         break;
1245                 case Opt_resgid:
1246                         if (match_int(&args[0], &option))
1247                                 return 0;
1248                         sbi->s_resgid = option;
1249                         break;
1250                 case Opt_sb:
1251                         /* handled by get_sb_block() instead of here */
1252                         /* *sb_block = match_int(&args[0]); */
1253                         break;
1254                 case Opt_err_panic:
1255                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1256                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1257                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1258                         break;
1259                 case Opt_err_ro:
1260                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1261                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1262                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1263                         break;
1264                 case Opt_err_cont:
1265                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1266                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1267                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1268                         break;
1269                 case Opt_nouid32:
1270                         set_opt(sbi->s_mount_opt, NO_UID32);
1271                         break;
1272                 case Opt_debug:
1273                         set_opt(sbi->s_mount_opt, DEBUG);
1274                         break;
1275                 case Opt_oldalloc:
1276                         set_opt(sbi->s_mount_opt, OLDALLOC);
1277                         break;
1278                 case Opt_orlov:
1279                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1280                         break;
1281 #ifdef CONFIG_EXT4_FS_XATTR
1282                 case Opt_user_xattr:
1283                         set_opt(sbi->s_mount_opt, XATTR_USER);
1284                         break;
1285                 case Opt_nouser_xattr:
1286                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1287                         break;
1288 #else
1289                 case Opt_user_xattr:
1290                 case Opt_nouser_xattr:
1291                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1292                         break;
1293 #endif
1294 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1295                 case Opt_acl:
1296                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1297                         break;
1298                 case Opt_noacl:
1299                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1300                         break;
1301 #else
1302                 case Opt_acl:
1303                 case Opt_noacl:
1304                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1305                         break;
1306 #endif
1307                 case Opt_journal_update:
1308                         /* @@@ FIXME */
1309                         /* Eventually we will want to be able to create
1310                            a journal file here.  For now, only allow the
1311                            user to specify an existing inode to be the
1312                            journal file. */
1313                         if (is_remount) {
1314                                 ext4_msg(sb, KERN_ERR,
1315                                          "Cannot specify journal on remount");
1316                                 return 0;
1317                         }
1318                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1319                         break;
1320                 case Opt_journal_dev:
1321                         if (is_remount) {
1322                                 ext4_msg(sb, KERN_ERR,
1323                                         "Cannot specify journal on remount");
1324                                 return 0;
1325                         }
1326                         if (match_int(&args[0], &option))
1327                                 return 0;
1328                         *journal_devnum = option;
1329                         break;
1330                 case Opt_journal_checksum:
1331                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1332                         break;
1333                 case Opt_journal_async_commit:
1334                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1335                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1336                         break;
1337                 case Opt_noload:
1338                         set_opt(sbi->s_mount_opt, NOLOAD);
1339                         break;
1340                 case Opt_commit:
1341                         if (match_int(&args[0], &option))
1342                                 return 0;
1343                         if (option < 0)
1344                                 return 0;
1345                         if (option == 0)
1346                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1347                         sbi->s_commit_interval = HZ * option;
1348                         break;
1349                 case Opt_max_batch_time:
1350                         if (match_int(&args[0], &option))
1351                                 return 0;
1352                         if (option < 0)
1353                                 return 0;
1354                         if (option == 0)
1355                                 option = EXT4_DEF_MAX_BATCH_TIME;
1356                         sbi->s_max_batch_time = option;
1357                         break;
1358                 case Opt_min_batch_time:
1359                         if (match_int(&args[0], &option))
1360                                 return 0;
1361                         if (option < 0)
1362                                 return 0;
1363                         sbi->s_min_batch_time = option;
1364                         break;
1365                 case Opt_data_journal:
1366                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1367                         goto datacheck;
1368                 case Opt_data_ordered:
1369                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1370                         goto datacheck;
1371                 case Opt_data_writeback:
1372                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1373                 datacheck:
1374                         if (is_remount) {
1375                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1376                                                 != data_opt) {
1377                                         ext4_msg(sb, KERN_ERR,
1378                                                 "Cannot change data mode on remount");
1379                                         return 0;
1380                                 }
1381                         } else {
1382                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1383                                 sbi->s_mount_opt |= data_opt;
1384                         }
1385                         break;
1386                 case Opt_data_err_abort:
1387                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1388                         break;
1389                 case Opt_data_err_ignore:
1390                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1391                         break;
1392 #ifdef CONFIG_QUOTA
1393                 case Opt_usrjquota:
1394                         qtype = USRQUOTA;
1395                         goto set_qf_name;
1396                 case Opt_grpjquota:
1397                         qtype = GRPQUOTA;
1398 set_qf_name:
1399                         if (sb_any_quota_loaded(sb) &&
1400                             !sbi->s_qf_names[qtype]) {
1401                                 ext4_msg(sb, KERN_ERR,
1402                                        "Cannot change journaled "
1403                                        "quota options when quota turned on");
1404                                 return 0;
1405                         }
1406                         qname = match_strdup(&args[0]);
1407                         if (!qname) {
1408                                 ext4_msg(sb, KERN_ERR,
1409                                         "Not enough memory for "
1410                                         "storing quotafile name");
1411                                 return 0;
1412                         }
1413                         if (sbi->s_qf_names[qtype] &&
1414                             strcmp(sbi->s_qf_names[qtype], qname)) {
1415                                 ext4_msg(sb, KERN_ERR,
1416                                         "%s quota file already "
1417                                         "specified", QTYPE2NAME(qtype));
1418                                 kfree(qname);
1419                                 return 0;
1420                         }
1421                         sbi->s_qf_names[qtype] = qname;
1422                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1423                                 ext4_msg(sb, KERN_ERR,
1424                                         "quotafile must be on "
1425                                         "filesystem root");
1426                                 kfree(sbi->s_qf_names[qtype]);
1427                                 sbi->s_qf_names[qtype] = NULL;
1428                                 return 0;
1429                         }
1430                         set_opt(sbi->s_mount_opt, QUOTA);
1431                         break;
1432                 case Opt_offusrjquota:
1433                         qtype = USRQUOTA;
1434                         goto clear_qf_name;
1435                 case Opt_offgrpjquota:
1436                         qtype = GRPQUOTA;
1437 clear_qf_name:
1438                         if (sb_any_quota_loaded(sb) &&
1439                             sbi->s_qf_names[qtype]) {
1440                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1441                                         "journaled quota options when "
1442                                         "quota turned on");
1443                                 return 0;
1444                         }
1445                         /*
1446                          * The space will be released later when all options
1447                          * are confirmed to be correct
1448                          */
1449                         sbi->s_qf_names[qtype] = NULL;
1450                         break;
1451                 case Opt_jqfmt_vfsold:
1452                         qfmt = QFMT_VFS_OLD;
1453                         goto set_qf_format;
1454                 case Opt_jqfmt_vfsv0:
1455                         qfmt = QFMT_VFS_V0;
1456                         goto set_qf_format;
1457                 case Opt_jqfmt_vfsv1:
1458                         qfmt = QFMT_VFS_V1;
1459 set_qf_format:
1460                         if (sb_any_quota_loaded(sb) &&
1461                             sbi->s_jquota_fmt != qfmt) {
1462                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1463                                         "journaled quota options when "
1464                                         "quota turned on");
1465                                 return 0;
1466                         }
1467                         sbi->s_jquota_fmt = qfmt;
1468                         break;
1469                 case Opt_quota:
1470                 case Opt_usrquota:
1471                         set_opt(sbi->s_mount_opt, QUOTA);
1472                         set_opt(sbi->s_mount_opt, USRQUOTA);
1473                         break;
1474                 case Opt_grpquota:
1475                         set_opt(sbi->s_mount_opt, QUOTA);
1476                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1477                         break;
1478                 case Opt_noquota:
1479                         if (sb_any_quota_loaded(sb)) {
1480                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1481                                         "options when quota turned on");
1482                                 return 0;
1483                         }
1484                         clear_opt(sbi->s_mount_opt, QUOTA);
1485                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1486                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1487                         break;
1488 #else
1489                 case Opt_quota:
1490                 case Opt_usrquota:
1491                 case Opt_grpquota:
1492                         ext4_msg(sb, KERN_ERR,
1493                                 "quota options not supported");
1494                         break;
1495                 case Opt_usrjquota:
1496                 case Opt_grpjquota:
1497                 case Opt_offusrjquota:
1498                 case Opt_offgrpjquota:
1499                 case Opt_jqfmt_vfsold:
1500                 case Opt_jqfmt_vfsv0:
1501                 case Opt_jqfmt_vfsv1:
1502                         ext4_msg(sb, KERN_ERR,
1503                                 "journaled quota options not supported");
1504                         break;
1505                 case Opt_noquota:
1506                         break;
1507 #endif
1508                 case Opt_abort:
1509                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1510                         break;
1511                 case Opt_nobarrier:
1512                         clear_opt(sbi->s_mount_opt, BARRIER);
1513                         break;
1514                 case Opt_barrier:
1515                         if (match_int(&args[0], &option)) {
1516                                 set_opt(sbi->s_mount_opt, BARRIER);
1517                                 break;
1518                         }
1519                         if (option)
1520                                 set_opt(sbi->s_mount_opt, BARRIER);
1521                         else
1522                                 clear_opt(sbi->s_mount_opt, BARRIER);
1523                         break;
1524                 case Opt_ignore:
1525                         break;
1526                 case Opt_resize:
1527                         if (!is_remount) {
1528                                 ext4_msg(sb, KERN_ERR,
1529                                         "resize option only available "
1530                                         "for remount");
1531                                 return 0;
1532                         }
1533                         if (match_int(&args[0], &option) != 0)
1534                                 return 0;
1535                         *n_blocks_count = option;
1536                         break;
1537                 case Opt_nobh:
1538                         set_opt(sbi->s_mount_opt, NOBH);
1539                         break;
1540                 case Opt_bh:
1541                         clear_opt(sbi->s_mount_opt, NOBH);
1542                         break;
1543                 case Opt_i_version:
1544                         set_opt(sbi->s_mount_opt, I_VERSION);
1545                         sb->s_flags |= MS_I_VERSION;
1546                         break;
1547                 case Opt_nodelalloc:
1548                         clear_opt(sbi->s_mount_opt, DELALLOC);
1549                         break;
1550                 case Opt_stripe:
1551                         if (match_int(&args[0], &option))
1552                                 return 0;
1553                         if (option < 0)
1554                                 return 0;
1555                         sbi->s_stripe = option;
1556                         break;
1557                 case Opt_delalloc:
1558                         set_opt(sbi->s_mount_opt, DELALLOC);
1559                         break;
1560                 case Opt_block_validity:
1561                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1562                         break;
1563                 case Opt_noblock_validity:
1564                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1565                         break;
1566                 case Opt_inode_readahead_blks:
1567                         if (match_int(&args[0], &option))
1568                                 return 0;
1569                         if (option < 0 || option > (1 << 30))
1570                                 return 0;
1571                         if (!is_power_of_2(option)) {
1572                                 ext4_msg(sb, KERN_ERR,
1573                                          "EXT4-fs: inode_readahead_blks"
1574                                          " must be a power of 2");
1575                                 return 0;
1576                         }
1577                         sbi->s_inode_readahead_blks = option;
1578                         break;
1579                 case Opt_journal_ioprio:
1580                         if (match_int(&args[0], &option))
1581                                 return 0;
1582                         if (option < 0 || option > 7)
1583                                 break;
1584                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1585                                                             option);
1586                         break;
1587                 case Opt_noauto_da_alloc:
1588                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1589                         break;
1590                 case Opt_auto_da_alloc:
1591                         if (match_int(&args[0], &option)) {
1592                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1593                                 break;
1594                         }
1595                         if (option)
1596                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1597                         else
1598                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1599                         break;
1600                 case Opt_discard:
1601                         set_opt(sbi->s_mount_opt, DISCARD);
1602                         break;
1603                 case Opt_nodiscard:
1604                         clear_opt(sbi->s_mount_opt, DISCARD);
1605                         break;
1606                 default:
1607                         ext4_msg(sb, KERN_ERR,
1608                                "Unrecognized mount option \"%s\" "
1609                                "or missing value", p);
1610                         return 0;
1611                 }
1612         }
1613 #ifdef CONFIG_QUOTA
1614         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1615                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1616                      sbi->s_qf_names[USRQUOTA])
1617                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1618
1619                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1620                      sbi->s_qf_names[GRPQUOTA])
1621                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1622
1623                 if ((sbi->s_qf_names[USRQUOTA] &&
1624                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1625                     (sbi->s_qf_names[GRPQUOTA] &&
1626                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1627                         ext4_msg(sb, KERN_ERR, "old and new quota "
1628                                         "format mixing");
1629                         return 0;
1630                 }
1631
1632                 if (!sbi->s_jquota_fmt) {
1633                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1634                                         "not specified");
1635                         return 0;
1636                 }
1637         } else {
1638                 if (sbi->s_jquota_fmt) {
1639                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1640                                         "specified with no journaling "
1641                                         "enabled");
1642                         return 0;
1643                 }
1644         }
1645 #endif
1646         return 1;
1647 }
1648
1649 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1650                             int read_only)
1651 {
1652         struct ext4_sb_info *sbi = EXT4_SB(sb);
1653         int res = 0;
1654
1655         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1656                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1657                          "forcing read-only mode");
1658                 res = MS_RDONLY;
1659         }
1660         if (read_only)
1661                 return res;
1662         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1663                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1664                          "running e2fsck is recommended");
1665         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1666                 ext4_msg(sb, KERN_WARNING,
1667                          "warning: mounting fs with errors, "
1668                          "running e2fsck is recommended");
1669         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1670                  le16_to_cpu(es->s_mnt_count) >=
1671                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1672                 ext4_msg(sb, KERN_WARNING,
1673                          "warning: maximal mount count reached, "
1674                          "running e2fsck is recommended");
1675         else if (le32_to_cpu(es->s_checkinterval) &&
1676                 (le32_to_cpu(es->s_lastcheck) +
1677                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1678                 ext4_msg(sb, KERN_WARNING,
1679                          "warning: checktime reached, "
1680                          "running e2fsck is recommended");
1681         if (!sbi->s_journal)
1682                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1683         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1684                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1685         le16_add_cpu(&es->s_mnt_count, 1);
1686         es->s_mtime = cpu_to_le32(get_seconds());
1687         ext4_update_dynamic_rev(sb);
1688         if (sbi->s_journal)
1689                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1690
1691         ext4_commit_super(sb, 1);
1692         if (test_opt(sb, DEBUG))
1693                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1694                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1695                         sb->s_blocksize,
1696                         sbi->s_groups_count,
1697                         EXT4_BLOCKS_PER_GROUP(sb),
1698                         EXT4_INODES_PER_GROUP(sb),
1699                         sbi->s_mount_opt);
1700
1701         return res;
1702 }
1703
1704 static int ext4_fill_flex_info(struct super_block *sb)
1705 {
1706         struct ext4_sb_info *sbi = EXT4_SB(sb);
1707         struct ext4_group_desc *gdp = NULL;
1708         ext4_group_t flex_group_count;
1709         ext4_group_t flex_group;
1710         int groups_per_flex = 0;
1711         size_t size;
1712         int i;
1713
1714         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1715         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1716
1717         if (groups_per_flex < 2) {
1718                 sbi->s_log_groups_per_flex = 0;
1719                 return 1;
1720         }
1721
1722         /* We allocate both existing and potentially added groups */
1723         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1724                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1725                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1726         size = flex_group_count * sizeof(struct flex_groups);
1727         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1728         if (sbi->s_flex_groups == NULL) {
1729                 sbi->s_flex_groups = vmalloc(size);
1730                 if (sbi->s_flex_groups)
1731                         memset(sbi->s_flex_groups, 0, size);
1732         }
1733         if (sbi->s_flex_groups == NULL) {
1734                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1735                                 "%u flex groups", flex_group_count);
1736                 goto failed;
1737         }
1738
1739         for (i = 0; i < sbi->s_groups_count; i++) {
1740                 gdp = ext4_get_group_desc(sb, i, NULL);
1741
1742                 flex_group = ext4_flex_group(sbi, i);
1743                 atomic_add(ext4_free_inodes_count(sb, gdp),
1744                            &sbi->s_flex_groups[flex_group].free_inodes);
1745                 atomic_add(ext4_free_blks_count(sb, gdp),
1746                            &sbi->s_flex_groups[flex_group].free_blocks);
1747                 atomic_add(ext4_used_dirs_count(sb, gdp),
1748                            &sbi->s_flex_groups[flex_group].used_dirs);
1749         }
1750
1751         return 1;
1752 failed:
1753         return 0;
1754 }
1755
1756 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1757                             struct ext4_group_desc *gdp)
1758 {
1759         __u16 crc = 0;
1760
1761         if (sbi->s_es->s_feature_ro_compat &
1762             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1763                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1764                 __le32 le_group = cpu_to_le32(block_group);
1765
1766                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1767                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1768                 crc = crc16(crc, (__u8 *)gdp, offset);
1769                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1770                 /* for checksum of struct ext4_group_desc do the rest...*/
1771                 if ((sbi->s_es->s_feature_incompat &
1772                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1773                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1774                         crc = crc16(crc, (__u8 *)gdp + offset,
1775                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1776                                         offset);
1777         }
1778
1779         return cpu_to_le16(crc);
1780 }
1781
1782 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1783                                 struct ext4_group_desc *gdp)
1784 {
1785         if ((sbi->s_es->s_feature_ro_compat &
1786              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1787             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1788                 return 0;
1789
1790         return 1;
1791 }
1792
1793 /* Called at mount-time, super-block is locked */
1794 static int ext4_check_descriptors(struct super_block *sb)
1795 {
1796         struct ext4_sb_info *sbi = EXT4_SB(sb);
1797         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1798         ext4_fsblk_t last_block;
1799         ext4_fsblk_t block_bitmap;
1800         ext4_fsblk_t inode_bitmap;
1801         ext4_fsblk_t inode_table;
1802         int flexbg_flag = 0;
1803         ext4_group_t i;
1804
1805         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1806                 flexbg_flag = 1;
1807
1808         ext4_debug("Checking group descriptors");
1809
1810         for (i = 0; i < sbi->s_groups_count; i++) {
1811                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1812
1813                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1814                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1815                 else
1816                         last_block = first_block +
1817                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1818
1819                 block_bitmap = ext4_block_bitmap(sb, gdp);
1820                 if (block_bitmap < first_block || block_bitmap > last_block) {
1821                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1822                                "Block bitmap for group %u not in group "
1823                                "(block %llu)!", i, block_bitmap);
1824                         return 0;
1825                 }
1826                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1827                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1828                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1829                                "Inode bitmap for group %u not in group "
1830                                "(block %llu)!", i, inode_bitmap);
1831                         return 0;
1832                 }
1833                 inode_table = ext4_inode_table(sb, gdp);
1834                 if (inode_table < first_block ||
1835                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1836                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1837                                "Inode table for group %u not in group "
1838                                "(block %llu)!", i, inode_table);
1839                         return 0;
1840                 }
1841                 ext4_lock_group(sb, i);
1842                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1843                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1844                                  "Checksum for group %u failed (%u!=%u)",
1845                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1846                                      gdp)), le16_to_cpu(gdp->bg_checksum));
1847                         if (!(sb->s_flags & MS_RDONLY)) {
1848                                 ext4_unlock_group(sb, i);
1849                                 return 0;
1850                         }
1851                 }
1852                 ext4_unlock_group(sb, i);
1853                 if (!flexbg_flag)
1854                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1855         }
1856
1857         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1858         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1859         return 1;
1860 }
1861
1862 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1863  * the superblock) which were deleted from all directories, but held open by
1864  * a process at the time of a crash.  We walk the list and try to delete these
1865  * inodes at recovery time (only with a read-write filesystem).
1866  *
1867  * In order to keep the orphan inode chain consistent during traversal (in
1868  * case of crash during recovery), we link each inode into the superblock
1869  * orphan list_head and handle it the same way as an inode deletion during
1870  * normal operation (which journals the operations for us).
1871  *
1872  * We only do an iget() and an iput() on each inode, which is very safe if we
1873  * accidentally point at an in-use or already deleted inode.  The worst that
1874  * can happen in this case is that we get a "bit already cleared" message from
1875  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1876  * e2fsck was run on this filesystem, and it must have already done the orphan
1877  * inode cleanup for us, so we can safely abort without any further action.
1878  */
1879 static void ext4_orphan_cleanup(struct super_block *sb,
1880                                 struct ext4_super_block *es)
1881 {
1882         unsigned int s_flags = sb->s_flags;
1883         int nr_orphans = 0, nr_truncates = 0;
1884 #ifdef CONFIG_QUOTA
1885         int i;
1886 #endif
1887         if (!es->s_last_orphan) {
1888                 jbd_debug(4, "no orphan inodes to clean up\n");
1889                 return;
1890         }
1891
1892         if (bdev_read_only(sb->s_bdev)) {
1893                 ext4_msg(sb, KERN_ERR, "write access "
1894                         "unavailable, skipping orphan cleanup");
1895                 return;
1896         }
1897
1898         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1899                 if (es->s_last_orphan)
1900                         jbd_debug(1, "Errors on filesystem, "
1901                                   "clearing orphan list.\n");
1902                 es->s_last_orphan = 0;
1903                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1904                 return;
1905         }
1906
1907         if (s_flags & MS_RDONLY) {
1908                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
1909                 sb->s_flags &= ~MS_RDONLY;
1910         }
1911 #ifdef CONFIG_QUOTA
1912         /* Needed for iput() to work correctly and not trash data */
1913         sb->s_flags |= MS_ACTIVE;
1914         /* Turn on quotas so that they are updated correctly */
1915         for (i = 0; i < MAXQUOTAS; i++) {
1916                 if (EXT4_SB(sb)->s_qf_names[i]) {
1917                         int ret = ext4_quota_on_mount(sb, i);
1918                         if (ret < 0)
1919                                 ext4_msg(sb, KERN_ERR,
1920                                         "Cannot turn on journaled "
1921                                         "quota: error %d", ret);
1922                 }
1923         }
1924 #endif
1925
1926         while (es->s_last_orphan) {
1927                 struct inode *inode;
1928
1929                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1930                 if (IS_ERR(inode)) {
1931                         es->s_last_orphan = 0;
1932                         break;
1933                 }
1934
1935                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1936                 vfs_dq_init(inode);
1937                 if (inode->i_nlink) {
1938                         ext4_msg(sb, KERN_DEBUG,
1939                                 "%s: truncating inode %lu to %lld bytes",
1940                                 __func__, inode->i_ino, inode->i_size);
1941                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1942                                   inode->i_ino, inode->i_size);
1943                         ext4_truncate(inode);
1944                         nr_truncates++;
1945                 } else {
1946                         ext4_msg(sb, KERN_DEBUG,
1947                                 "%s: deleting unreferenced inode %lu",
1948                                 __func__, inode->i_ino);
1949                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1950                                   inode->i_ino);
1951                         nr_orphans++;
1952                 }
1953                 iput(inode);  /* The delete magic happens here! */
1954         }
1955
1956 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1957
1958         if (nr_orphans)
1959                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
1960                        PLURAL(nr_orphans));
1961         if (nr_truncates)
1962                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
1963                        PLURAL(nr_truncates));
1964 #ifdef CONFIG_QUOTA
1965         /* Turn quotas off */
1966         for (i = 0; i < MAXQUOTAS; i++) {
1967                 if (sb_dqopt(sb)->files[i])
1968                         vfs_quota_off(sb, i, 0);
1969         }
1970 #endif
1971         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1972 }
1973
1974 /*
1975  * Maximal extent format file size.
1976  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1977  * extent format containers, within a sector_t, and within i_blocks
1978  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1979  * so that won't be a limiting factor.
1980  *
1981  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1982  */
1983 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1984 {
1985         loff_t res;
1986         loff_t upper_limit = MAX_LFS_FILESIZE;
1987
1988         /* small i_blocks in vfs inode? */
1989         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1990                 /*
1991                  * CONFIG_LBDAF is not enabled implies the inode
1992                  * i_block represent total blocks in 512 bytes
1993                  * 32 == size of vfs inode i_blocks * 8
1994                  */
1995                 upper_limit = (1LL << 32) - 1;
1996
1997                 /* total blocks in file system block size */
1998                 upper_limit >>= (blkbits - 9);
1999                 upper_limit <<= blkbits;
2000         }
2001
2002         /* 32-bit extent-start container, ee_block */
2003         res = 1LL << 32;
2004         res <<= blkbits;
2005         res -= 1;
2006
2007         /* Sanity check against vm- & vfs- imposed limits */
2008         if (res > upper_limit)
2009                 res = upper_limit;
2010
2011         return res;
2012 }
2013
2014 /*
2015  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2016  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2017  * We need to be 1 filesystem block less than the 2^48 sector limit.
2018  */
2019 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2020 {
2021         loff_t res = EXT4_NDIR_BLOCKS;
2022         int meta_blocks;
2023         loff_t upper_limit;
2024         /* This is calculated to be the largest file size for a dense, block
2025          * mapped file such that the file's total number of 512-byte sectors,
2026          * including data and all indirect blocks, does not exceed (2^48 - 1).
2027          *
2028          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2029          * number of 512-byte sectors of the file.
2030          */
2031
2032         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2033                 /*
2034                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2035                  * the inode i_block field represents total file blocks in
2036                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2037                  */
2038                 upper_limit = (1LL << 32) - 1;
2039
2040                 /* total blocks in file system block size */
2041                 upper_limit >>= (bits - 9);
2042
2043         } else {
2044                 /*
2045                  * We use 48 bit ext4_inode i_blocks
2046                  * With EXT4_HUGE_FILE_FL set the i_blocks
2047                  * represent total number of blocks in
2048                  * file system block size
2049                  */
2050                 upper_limit = (1LL << 48) - 1;
2051
2052         }
2053
2054         /* indirect blocks */
2055         meta_blocks = 1;
2056         /* double indirect blocks */
2057         meta_blocks += 1 + (1LL << (bits-2));
2058         /* tripple indirect blocks */
2059         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2060
2061         upper_limit -= meta_blocks;
2062         upper_limit <<= bits;
2063
2064         res += 1LL << (bits-2);
2065         res += 1LL << (2*(bits-2));
2066         res += 1LL << (3*(bits-2));
2067         res <<= bits;
2068         if (res > upper_limit)
2069                 res = upper_limit;
2070
2071         if (res > MAX_LFS_FILESIZE)
2072                 res = MAX_LFS_FILESIZE;
2073
2074         return res;
2075 }
2076
2077 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2078                                    ext4_fsblk_t logical_sb_block, int nr)
2079 {
2080         struct ext4_sb_info *sbi = EXT4_SB(sb);
2081         ext4_group_t bg, first_meta_bg;
2082         int has_super = 0;
2083
2084         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2085
2086         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2087             nr < first_meta_bg)
2088                 return logical_sb_block + nr + 1;
2089         bg = sbi->s_desc_per_block * nr;
2090         if (ext4_bg_has_super(sb, bg))
2091                 has_super = 1;
2092
2093         return (has_super + ext4_group_first_block_no(sb, bg));
2094 }
2095
2096 /**
2097  * ext4_get_stripe_size: Get the stripe size.
2098  * @sbi: In memory super block info
2099  *
2100  * If we have specified it via mount option, then
2101  * use the mount option value. If the value specified at mount time is
2102  * greater than the blocks per group use the super block value.
2103  * If the super block value is greater than blocks per group return 0.
2104  * Allocator needs it be less than blocks per group.
2105  *
2106  */
2107 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2108 {
2109         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2110         unsigned long stripe_width =
2111                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2112
2113         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2114                 return sbi->s_stripe;
2115
2116         if (stripe_width <= sbi->s_blocks_per_group)
2117                 return stripe_width;
2118
2119         if (stride <= sbi->s_blocks_per_group)
2120                 return stride;
2121
2122         return 0;
2123 }
2124
2125 /* sysfs supprt */
2126
2127 struct ext4_attr {
2128         struct attribute attr;
2129         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2130         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *, 
2131                          const char *, size_t);
2132         int offset;
2133 };
2134
2135 static int parse_strtoul(const char *buf,
2136                 unsigned long max, unsigned long *value)
2137 {
2138         char *endp;
2139
2140         while (*buf && isspace(*buf))
2141                 buf++;
2142         *value = simple_strtoul(buf, &endp, 0);
2143         while (*endp && isspace(*endp))
2144                 endp++;
2145         if (*endp || *value > max)
2146                 return -EINVAL;
2147
2148         return 0;
2149 }
2150
2151 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2152                                               struct ext4_sb_info *sbi,
2153                                               char *buf)
2154 {
2155         return snprintf(buf, PAGE_SIZE, "%llu\n",
2156                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2157 }
2158
2159 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2160                                          struct ext4_sb_info *sbi, char *buf)
2161 {
2162         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2163
2164         return snprintf(buf, PAGE_SIZE, "%lu\n",
2165                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2166                          sbi->s_sectors_written_start) >> 1);
2167 }
2168
2169 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2170                                           struct ext4_sb_info *sbi, char *buf)
2171 {
2172         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2173
2174         return snprintf(buf, PAGE_SIZE, "%llu\n",
2175                         sbi->s_kbytes_written + 
2176                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2177                           EXT4_SB(sb)->s_sectors_written_start) >> 1));
2178 }
2179
2180 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2181                                           struct ext4_sb_info *sbi,
2182                                           const char *buf, size_t count)
2183 {
2184         unsigned long t;
2185
2186         if (parse_strtoul(buf, 0x40000000, &t))
2187                 return -EINVAL;
2188
2189         if (!is_power_of_2(t))
2190                 return -EINVAL;
2191
2192         sbi->s_inode_readahead_blks = t;
2193         return count;
2194 }
2195
2196 static ssize_t sbi_ui_show(struct ext4_attr *a,
2197                            struct ext4_sb_info *sbi, char *buf)
2198 {
2199         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2200
2201         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2202 }
2203
2204 static ssize_t sbi_ui_store(struct ext4_attr *a,
2205                             struct ext4_sb_info *sbi,
2206                             const char *buf, size_t count)
2207 {
2208         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2209         unsigned long t;
2210
2211         if (parse_strtoul(buf, 0xffffffff, &t))
2212                 return -EINVAL;
2213         *ui = t;
2214         return count;
2215 }
2216
2217 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2218 static struct ext4_attr ext4_attr_##_name = {                   \
2219         .attr = {.name = __stringify(_name), .mode = _mode },   \
2220         .show   = _show,                                        \
2221         .store  = _store,                                       \
2222         .offset = offsetof(struct ext4_sb_info, _elname),       \
2223 }
2224 #define EXT4_ATTR(name, mode, show, store) \
2225 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2226
2227 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2228 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2229 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2230         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2231 #define ATTR_LIST(name) &ext4_attr_##name.attr
2232
2233 EXT4_RO_ATTR(delayed_allocation_blocks);
2234 EXT4_RO_ATTR(session_write_kbytes);
2235 EXT4_RO_ATTR(lifetime_write_kbytes);
2236 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2237                  inode_readahead_blks_store, s_inode_readahead_blks);
2238 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2239 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2240 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2241 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2242 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2243 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2244 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2245 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2246
2247 static struct attribute *ext4_attrs[] = {
2248         ATTR_LIST(delayed_allocation_blocks),
2249         ATTR_LIST(session_write_kbytes),
2250         ATTR_LIST(lifetime_write_kbytes),
2251         ATTR_LIST(inode_readahead_blks),
2252         ATTR_LIST(inode_goal),
2253         ATTR_LIST(mb_stats),
2254         ATTR_LIST(mb_max_to_scan),
2255         ATTR_LIST(mb_min_to_scan),
2256         ATTR_LIST(mb_order2_req),
2257         ATTR_LIST(mb_stream_req),
2258         ATTR_LIST(mb_group_prealloc),
2259         ATTR_LIST(max_writeback_mb_bump),
2260         NULL,
2261 };
2262
2263 static ssize_t ext4_attr_show(struct kobject *kobj,
2264                               struct attribute *attr, char *buf)
2265 {
2266         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2267                                                 s_kobj);
2268         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2269
2270         return a->show ? a->show(a, sbi, buf) : 0;
2271 }
2272
2273 static ssize_t ext4_attr_store(struct kobject *kobj,
2274                                struct attribute *attr,
2275                                const char *buf, size_t len)
2276 {
2277         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2278                                                 s_kobj);
2279         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2280
2281         return a->store ? a->store(a, sbi, buf, len) : 0;
2282 }
2283
2284 static void ext4_sb_release(struct kobject *kobj)
2285 {
2286         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2287                                                 s_kobj);
2288         complete(&sbi->s_kobj_unregister);
2289 }
2290
2291
2292 static struct sysfs_ops ext4_attr_ops = {
2293         .show   = ext4_attr_show,
2294         .store  = ext4_attr_store,
2295 };
2296
2297 static struct kobj_type ext4_ktype = {
2298         .default_attrs  = ext4_attrs,
2299         .sysfs_ops      = &ext4_attr_ops,
2300         .release        = ext4_sb_release,
2301 };
2302
2303 /*
2304  * Check whether this filesystem can be mounted based on
2305  * the features present and the RDONLY/RDWR mount requested.
2306  * Returns 1 if this filesystem can be mounted as requested,
2307  * 0 if it cannot be.
2308  */
2309 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2310 {
2311         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2312                 ext4_msg(sb, KERN_ERR,
2313                         "Couldn't mount because of "
2314                         "unsupported optional features (%x)",
2315                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2316                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2317                 return 0;
2318         }
2319
2320         if (readonly)
2321                 return 1;
2322
2323         /* Check that feature set is OK for a read-write mount */
2324         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2325                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2326                          "unsupported optional features (%x)",
2327                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2328                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2329                 return 0;
2330         }
2331         /*
2332          * Large file size enabled file system can only be mounted
2333          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2334          */
2335         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2336                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2337                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2338                                  "cannot be mounted RDWR without "
2339                                  "CONFIG_LBDAF");
2340                         return 0;
2341                 }
2342         }
2343         return 1;
2344 }
2345
2346 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2347                                 __releases(kernel_lock)
2348                                 __acquires(kernel_lock)
2349 {
2350         struct buffer_head *bh;
2351         struct ext4_super_block *es = NULL;
2352         struct ext4_sb_info *sbi;
2353         ext4_fsblk_t block;
2354         ext4_fsblk_t sb_block = get_sb_block(&data);
2355         ext4_fsblk_t logical_sb_block;
2356         unsigned long offset = 0;
2357         unsigned long journal_devnum = 0;
2358         unsigned long def_mount_opts;
2359         struct inode *root;
2360         char *cp;
2361         const char *descr;
2362         int ret = -EINVAL;
2363         int blocksize;
2364         unsigned int db_count;
2365         unsigned int i;
2366         int needs_recovery, has_huge_files;
2367         __u64 blocks_count;
2368         int err;
2369         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2370
2371         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2372         if (!sbi)
2373                 return -ENOMEM;
2374
2375         sbi->s_blockgroup_lock =
2376                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2377         if (!sbi->s_blockgroup_lock) {
2378                 kfree(sbi);
2379                 return -ENOMEM;
2380         }
2381         sb->s_fs_info = sbi;
2382         sbi->s_mount_opt = 0;
2383         sbi->s_resuid = EXT4_DEF_RESUID;
2384         sbi->s_resgid = EXT4_DEF_RESGID;
2385         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2386         sbi->s_sb_block = sb_block;
2387         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2388                                                       sectors[1]);
2389
2390         unlock_kernel();
2391
2392         /* Cleanup superblock name */
2393         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2394                 *cp = '!';
2395
2396         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2397         if (!blocksize) {
2398                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2399                 goto out_fail;
2400         }
2401
2402         /*
2403          * The ext4 superblock will not be buffer aligned for other than 1kB
2404          * block sizes.  We need to calculate the offset from buffer start.
2405          */
2406         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2407                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2408                 offset = do_div(logical_sb_block, blocksize);
2409         } else {
2410                 logical_sb_block = sb_block;
2411         }
2412
2413         if (!(bh = sb_bread(sb, logical_sb_block))) {
2414                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2415                 goto out_fail;
2416         }
2417         /*
2418          * Note: s_es must be initialized as soon as possible because
2419          *       some ext4 macro-instructions depend on its value
2420          */
2421         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2422         sbi->s_es = es;
2423         sb->s_magic = le16_to_cpu(es->s_magic);
2424         if (sb->s_magic != EXT4_SUPER_MAGIC)
2425                 goto cantfind_ext4;
2426         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2427
2428         /* Set defaults before we parse the mount options */
2429         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2430         if (def_mount_opts & EXT4_DEFM_DEBUG)
2431                 set_opt(sbi->s_mount_opt, DEBUG);
2432         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
2433                 set_opt(sbi->s_mount_opt, GRPID);
2434         if (def_mount_opts & EXT4_DEFM_UID16)
2435                 set_opt(sbi->s_mount_opt, NO_UID32);
2436 #ifdef CONFIG_EXT4_FS_XATTR
2437         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2438                 set_opt(sbi->s_mount_opt, XATTR_USER);
2439 #endif
2440 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2441         if (def_mount_opts & EXT4_DEFM_ACL)
2442                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2443 #endif
2444         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2445                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2446         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2447                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2448         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2449                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2450
2451         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2452                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2453         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2454                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2455         else
2456                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2457
2458         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2459         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2460         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2461         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2462         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2463
2464         set_opt(sbi->s_mount_opt, BARRIER);
2465
2466         /*
2467          * enable delayed allocation by default
2468          * Use -o nodelalloc to turn it off
2469          */
2470         set_opt(sbi->s_mount_opt, DELALLOC);
2471
2472         if (!parse_options((char *) data, sb, &journal_devnum,
2473                            &journal_ioprio, NULL, 0))
2474                 goto failed_mount;
2475
2476         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2477                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2478
2479         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2480             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2481              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2482              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2483                 ext4_msg(sb, KERN_WARNING,
2484                        "feature flags set on rev 0 fs, "
2485                        "running e2fsck is recommended");
2486
2487         /*
2488          * Check feature flags regardless of the revision level, since we
2489          * previously didn't change the revision level when setting the flags,
2490          * so there is a chance incompat flags are set on a rev 0 filesystem.
2491          */
2492         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
2493                 goto failed_mount;
2494
2495         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2496
2497         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2498             blocksize > EXT4_MAX_BLOCK_SIZE) {
2499                 ext4_msg(sb, KERN_ERR,
2500                        "Unsupported filesystem blocksize %d", blocksize);
2501                 goto failed_mount;
2502         }
2503
2504         if (sb->s_blocksize != blocksize) {
2505                 /* Validate the filesystem blocksize */
2506                 if (!sb_set_blocksize(sb, blocksize)) {
2507                         ext4_msg(sb, KERN_ERR, "bad block size %d",
2508                                         blocksize);
2509                         goto failed_mount;
2510                 }
2511
2512                 brelse(bh);
2513                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2514                 offset = do_div(logical_sb_block, blocksize);
2515                 bh = sb_bread(sb, logical_sb_block);
2516                 if (!bh) {
2517                         ext4_msg(sb, KERN_ERR,
2518                                "Can't read superblock on 2nd try");
2519                         goto failed_mount;
2520                 }
2521                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2522                 sbi->s_es = es;
2523                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2524                         ext4_msg(sb, KERN_ERR,
2525                                "Magic mismatch, very weird!");
2526                         goto failed_mount;
2527                 }
2528         }
2529
2530         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2531                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2532         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2533                                                       has_huge_files);
2534         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2535
2536         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2537                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2538                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2539         } else {
2540                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2541                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2542                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2543                     (!is_power_of_2(sbi->s_inode_size)) ||
2544                     (sbi->s_inode_size > blocksize)) {
2545                         ext4_msg(sb, KERN_ERR,
2546                                "unsupported inode size: %d",
2547                                sbi->s_inode_size);
2548                         goto failed_mount;
2549                 }
2550                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2551                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2552         }
2553
2554         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2555         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2556                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2557                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2558                     !is_power_of_2(sbi->s_desc_size)) {
2559                         ext4_msg(sb, KERN_ERR,
2560                                "unsupported descriptor size %lu",
2561                                sbi->s_desc_size);
2562                         goto failed_mount;
2563                 }
2564         } else
2565                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2566
2567         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2568         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2569         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2570                 goto cantfind_ext4;
2571
2572         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2573         if (sbi->s_inodes_per_block == 0)
2574                 goto cantfind_ext4;
2575         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2576                                         sbi->s_inodes_per_block;
2577         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2578         sbi->s_sbh = bh;
2579         sbi->s_mount_state = le16_to_cpu(es->s_state);
2580         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2581         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2582
2583         for (i = 0; i < 4; i++)
2584                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2585         sbi->s_def_hash_version = es->s_def_hash_version;
2586         i = le32_to_cpu(es->s_flags);
2587         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2588                 sbi->s_hash_unsigned = 3;
2589         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2590 #ifdef __CHAR_UNSIGNED__
2591                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2592                 sbi->s_hash_unsigned = 3;
2593 #else
2594                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2595 #endif
2596                 sb->s_dirt = 1;
2597         }
2598
2599         if (sbi->s_blocks_per_group > blocksize * 8) {
2600                 ext4_msg(sb, KERN_ERR,
2601                        "#blocks per group too big: %lu",
2602                        sbi->s_blocks_per_group);
2603                 goto failed_mount;
2604         }
2605         if (sbi->s_inodes_per_group > blocksize * 8) {
2606                 ext4_msg(sb, KERN_ERR,
2607                        "#inodes per group too big: %lu",
2608                        sbi->s_inodes_per_group);
2609                 goto failed_mount;
2610         }
2611
2612         /*
2613          * Test whether we have more sectors than will fit in sector_t,
2614          * and whether the max offset is addressable by the page cache.
2615          */
2616         if ((ext4_blocks_count(es) >
2617              (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
2618             (ext4_blocks_count(es) >
2619              (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
2620                 ext4_msg(sb, KERN_ERR, "filesystem"
2621                          " too large to mount safely on this system");
2622                 if (sizeof(sector_t) < 8)
2623                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
2624                 ret = -EFBIG;
2625                 goto failed_mount;
2626         }
2627
2628         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2629                 goto cantfind_ext4;
2630
2631         /* check blocks count against device size */
2632         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2633         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2634                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2635                        "exceeds size of device (%llu blocks)",
2636                        ext4_blocks_count(es), blocks_count);
2637                 goto failed_mount;
2638         }
2639
2640         /*
2641          * It makes no sense for the first data block to be beyond the end
2642          * of the filesystem.
2643          */
2644         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2645                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2646                          "block %u is beyond end of filesystem (%llu)",
2647                          le32_to_cpu(es->s_first_data_block),
2648                          ext4_blocks_count(es));
2649                 goto failed_mount;
2650         }
2651         blocks_count = (ext4_blocks_count(es) -
2652                         le32_to_cpu(es->s_first_data_block) +
2653                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2654         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2655         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2656                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2657                        "(block count %llu, first data block %u, "
2658                        "blocks per group %lu)", sbi->s_groups_count,
2659                        ext4_blocks_count(es),
2660                        le32_to_cpu(es->s_first_data_block),
2661                        EXT4_BLOCKS_PER_GROUP(sb));
2662                 goto failed_mount;
2663         }
2664         sbi->s_groups_count = blocks_count;
2665         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
2666                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
2667         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2668                    EXT4_DESC_PER_BLOCK(sb);
2669         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2670                                     GFP_KERNEL);
2671         if (sbi->s_group_desc == NULL) {
2672                 ext4_msg(sb, KERN_ERR, "not enough memory");
2673                 goto failed_mount;
2674         }
2675
2676 #ifdef CONFIG_PROC_FS
2677         if (ext4_proc_root)
2678                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2679 #endif
2680
2681         bgl_lock_init(sbi->s_blockgroup_lock);
2682
2683         for (i = 0; i < db_count; i++) {
2684                 block = descriptor_loc(sb, logical_sb_block, i);
2685                 sbi->s_group_desc[i] = sb_bread(sb, block);
2686                 if (!sbi->s_group_desc[i]) {
2687                         ext4_msg(sb, KERN_ERR,
2688                                "can't read group descriptor %d", i);
2689                         db_count = i;
2690                         goto failed_mount2;
2691                 }
2692         }
2693         if (!ext4_check_descriptors(sb)) {
2694                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2695                 goto failed_mount2;
2696         }
2697         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2698                 if (!ext4_fill_flex_info(sb)) {
2699                         ext4_msg(sb, KERN_ERR,
2700                                "unable to initialize "
2701                                "flex_bg meta info!");
2702                         goto failed_mount2;
2703                 }
2704
2705         sbi->s_gdb_count = db_count;
2706         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2707         spin_lock_init(&sbi->s_next_gen_lock);
2708
2709         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2710                         ext4_count_free_blocks(sb));
2711         if (!err) {
2712                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2713                                 ext4_count_free_inodes(sb));
2714         }
2715         if (!err) {
2716                 err = percpu_counter_init(&sbi->s_dirs_counter,
2717                                 ext4_count_dirs(sb));
2718         }
2719         if (!err) {
2720                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2721         }
2722         if (err) {
2723                 ext4_msg(sb, KERN_ERR, "insufficient memory");
2724                 goto failed_mount3;
2725         }
2726
2727         sbi->s_stripe = ext4_get_stripe_size(sbi);
2728         sbi->s_max_writeback_mb_bump = 128;
2729
2730         /*
2731          * set up enough so that it can read an inode
2732          */
2733         if (!test_opt(sb, NOLOAD) &&
2734             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2735                 sb->s_op = &ext4_sops;
2736         else
2737                 sb->s_op = &ext4_nojournal_sops;
2738         sb->s_export_op = &ext4_export_ops;
2739         sb->s_xattr = ext4_xattr_handlers;
2740 #ifdef CONFIG_QUOTA
2741         sb->s_qcop = &ext4_qctl_operations;
2742         sb->dq_op = &ext4_quota_operations;
2743 #endif
2744         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2745         mutex_init(&sbi->s_orphan_lock);
2746         mutex_init(&sbi->s_resize_lock);
2747
2748         sb->s_root = NULL;
2749
2750         needs_recovery = (es->s_last_orphan != 0 ||
2751                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2752                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2753
2754         /*
2755          * The first inode we look at is the journal inode.  Don't try
2756          * root first: it may be modified in the journal!
2757          */
2758         if (!test_opt(sb, NOLOAD) &&
2759             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2760                 if (ext4_load_journal(sb, es, journal_devnum))
2761                         goto failed_mount3;
2762         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2763               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2764                 ext4_msg(sb, KERN_ERR, "required journal recovery "
2765                        "suppressed and not mounted read-only");
2766                 goto failed_mount4;
2767         } else {
2768                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2769                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2770                 sbi->s_journal = NULL;
2771                 needs_recovery = 0;
2772                 goto no_journal;
2773         }
2774
2775         if (ext4_blocks_count(es) > 0xffffffffULL &&
2776             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2777                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2778                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
2779                 goto failed_mount4;
2780         }
2781
2782         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2783                 jbd2_journal_set_features(sbi->s_journal,
2784                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2785                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2786         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2787                 jbd2_journal_set_features(sbi->s_journal,
2788                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2789                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2790                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2791         } else {
2792                 jbd2_journal_clear_features(sbi->s_journal,
2793                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2794                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2795         }
2796
2797         /* We have now updated the journal if required, so we can
2798          * validate the data journaling mode. */
2799         switch (test_opt(sb, DATA_FLAGS)) {
2800         case 0:
2801                 /* No mode set, assume a default based on the journal
2802                  * capabilities: ORDERED_DATA if the journal can
2803                  * cope, else JOURNAL_DATA
2804                  */
2805                 if (jbd2_journal_check_available_features
2806                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2807                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2808                 else
2809                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2810                 break;
2811
2812         case EXT4_MOUNT_ORDERED_DATA:
2813         case EXT4_MOUNT_WRITEBACK_DATA:
2814                 if (!jbd2_journal_check_available_features
2815                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2816                         ext4_msg(sb, KERN_ERR, "Journal does not support "
2817                                "requested data journaling mode");
2818                         goto failed_mount4;
2819                 }
2820         default:
2821                 break;
2822         }
2823         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2824
2825 no_journal:
2826
2827         if (test_opt(sb, NOBH)) {
2828                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2829                         ext4_msg(sb, KERN_WARNING, "Ignoring nobh option - "
2830                                 "its supported only with writeback mode");
2831                         clear_opt(sbi->s_mount_opt, NOBH);
2832                 }
2833         }
2834         EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten");
2835         if (!EXT4_SB(sb)->dio_unwritten_wq) {
2836                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
2837                 goto failed_mount_wq;
2838         }
2839
2840         /*
2841          * The jbd2_journal_load will have done any necessary log recovery,
2842          * so we can safely mount the rest of the filesystem now.
2843          */
2844
2845         root = ext4_iget(sb, EXT4_ROOT_INO);
2846         if (IS_ERR(root)) {
2847                 ext4_msg(sb, KERN_ERR, "get root inode failed");
2848                 ret = PTR_ERR(root);
2849                 goto failed_mount4;
2850         }
2851         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2852                 iput(root);
2853                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
2854                 goto failed_mount4;
2855         }
2856         sb->s_root = d_alloc_root(root);
2857         if (!sb->s_root) {
2858                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
2859                 iput(root);
2860                 ret = -ENOMEM;
2861                 goto failed_mount4;
2862         }
2863
2864         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2865
2866         /* determine the minimum size of new large inodes, if present */
2867         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2868                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2869                                                      EXT4_GOOD_OLD_INODE_SIZE;
2870                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2871                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2872                         if (sbi->s_want_extra_isize <
2873                             le16_to_cpu(es->s_want_extra_isize))
2874                                 sbi->s_want_extra_isize =
2875                                         le16_to_cpu(es->s_want_extra_isize);
2876                         if (sbi->s_want_extra_isize <
2877                             le16_to_cpu(es->s_min_extra_isize))
2878                                 sbi->s_want_extra_isize =
2879                                         le16_to_cpu(es->s_min_extra_isize);
2880                 }
2881         }
2882         /* Check if enough inode space is available */
2883         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2884                                                         sbi->s_inode_size) {
2885                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2886                                                        EXT4_GOOD_OLD_INODE_SIZE;
2887                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
2888                          "available");
2889         }
2890
2891         if (test_opt(sb, DELALLOC) &&
2892             (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2893                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
2894                          "requested data journaling mode");
2895                 clear_opt(sbi->s_mount_opt, DELALLOC);
2896         }
2897
2898         err = ext4_setup_system_zone(sb);
2899         if (err) {
2900                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
2901                          "zone (%d)\n", err);
2902                 goto failed_mount4;
2903         }
2904
2905         ext4_ext_init(sb);
2906         err = ext4_mb_init(sb, needs_recovery);
2907         if (err) {
2908                 ext4_msg(sb, KERN_ERR, "failed to initalize mballoc (%d)",
2909                          err);
2910                 goto failed_mount4;
2911         }
2912
2913         sbi->s_kobj.kset = ext4_kset;
2914         init_completion(&sbi->s_kobj_unregister);
2915         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
2916                                    "%s", sb->s_id);
2917         if (err) {
2918                 ext4_mb_release(sb);
2919                 ext4_ext_release(sb);
2920                 goto failed_mount4;
2921         };
2922
2923         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2924         ext4_orphan_cleanup(sb, es);
2925         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2926         if (needs_recovery) {
2927                 ext4_msg(sb, KERN_INFO, "recovery complete");
2928                 ext4_mark_recovery_complete(sb, es);
2929         }
2930         if (EXT4_SB(sb)->s_journal) {
2931                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2932                         descr = " journalled data mode";
2933                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2934                         descr = " ordered data mode";
2935                 else
2936                         descr = " writeback data mode";
2937         } else
2938                 descr = "out journal";
2939
2940         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s", descr);
2941
2942         lock_kernel();
2943         return 0;
2944
2945 cantfind_ext4:
2946         if (!silent)
2947                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
2948         goto failed_mount;
2949
2950 failed_mount4:
2951         ext4_msg(sb, KERN_ERR, "mount failed");
2952         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
2953 failed_mount_wq:
2954         ext4_release_system_zone(sb);
2955         if (sbi->s_journal) {
2956                 jbd2_journal_destroy(sbi->s_journal);
2957                 sbi->s_journal = NULL;
2958         }
2959 failed_mount3:
2960         if (sbi->s_flex_groups) {
2961                 if (is_vmalloc_addr(sbi->s_flex_groups))
2962                         vfree(sbi->s_flex_groups);
2963                 else
2964                         kfree(sbi->s_flex_groups);
2965         }
2966         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2967         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2968         percpu_counter_destroy(&sbi->s_dirs_counter);
2969         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2970 failed_mount2:
2971         for (i = 0; i < db_count; i++)
2972                 brelse(sbi->s_group_desc[i]);
2973         kfree(sbi->s_group_desc);
2974 failed_mount:
2975         if (sbi->s_proc) {
2976                 remove_proc_entry(sb->s_id, ext4_proc_root);
2977         }
2978 #ifdef CONFIG_QUOTA
2979         for (i = 0; i < MAXQUOTAS; i++)
2980                 kfree(sbi->s_qf_names[i]);
2981 #endif
2982         ext4_blkdev_remove(sbi);
2983         brelse(bh);
2984 out_fail:
2985         sb->s_fs_info = NULL;
2986         kfree(sbi->s_blockgroup_lock);
2987         kfree(sbi);
2988         lock_kernel();
2989         return ret;
2990 }
2991
2992 /*
2993  * Setup any per-fs journal parameters now.  We'll do this both on
2994  * initial mount, once the journal has been initialised but before we've
2995  * done any recovery; and again on any subsequent remount.
2996  */
2997 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2998 {
2999         struct ext4_sb_info *sbi = EXT4_SB(sb);
3000
3001         journal->j_commit_interval = sbi->s_commit_interval;
3002         journal->j_min_batch_time = sbi->s_min_batch_time;
3003         journal->j_max_batch_time = sbi->s_max_batch_time;
3004
3005         spin_lock(&journal->j_state_lock);
3006         if (test_opt(sb, BARRIER))
3007                 journal->j_flags |= JBD2_BARRIER;
3008         else
3009                 journal->j_flags &= ~JBD2_BARRIER;
3010         if (test_opt(sb, DATA_ERR_ABORT))
3011                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3012         else
3013                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3014         spin_unlock(&journal->j_state_lock);
3015 }
3016
3017 static journal_t *ext4_get_journal(struct super_block *sb,
3018                                    unsigned int journal_inum)
3019 {
3020         struct inode *journal_inode;
3021         journal_t *journal;
3022
3023         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3024
3025         /* First, test for the existence of a valid inode on disk.  Bad
3026          * things happen if we iget() an unused inode, as the subsequent
3027          * iput() will try to delete it. */
3028
3029         journal_inode = ext4_iget(sb, journal_inum);
3030         if (IS_ERR(journal_inode)) {
3031                 ext4_msg(sb, KERN_ERR, "no journal found");
3032                 return NULL;
3033         }
3034         if (!journal_inode->i_nlink) {
3035                 make_bad_inode(journal_inode);
3036                 iput(journal_inode);
3037                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3038                 return NULL;
3039         }
3040
3041         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3042                   journal_inode, journal_inode->i_size);
3043         if (!S_ISREG(journal_inode->i_mode)) {
3044                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3045                 iput(journal_inode);
3046                 return NULL;
3047         }
3048
3049         journal = jbd2_journal_init_inode(journal_inode);
3050         if (!journal) {
3051                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3052                 iput(journal_inode);
3053                 return NULL;
3054         }
3055         journal->j_private = sb;
3056         ext4_init_journal_params(sb, journal);
3057         return journal;
3058 }
3059
3060 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3061                                        dev_t j_dev)
3062 {
3063         struct buffer_head *bh;
3064         journal_t *journal;
3065         ext4_fsblk_t start;
3066         ext4_fsblk_t len;
3067         int hblock, blocksize;
3068         ext4_fsblk_t sb_block;
3069         unsigned long offset;
3070         struct ext4_super_block *es;
3071         struct block_device *bdev;
3072
3073         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3074
3075         bdev = ext4_blkdev_get(j_dev, sb);
3076         if (bdev == NULL)
3077                 return NULL;
3078
3079         if (bd_claim(bdev, sb)) {
3080                 ext4_msg(sb, KERN_ERR,
3081                         "failed to claim external journal device");
3082                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3083                 return NULL;
3084         }
3085
3086         blocksize = sb->s_blocksize;
3087         hblock = bdev_logical_block_size(bdev);
3088         if (blocksize < hblock) {
3089                 ext4_msg(sb, KERN_ERR,
3090                         "blocksize too small for journal device");
3091                 goto out_bdev;
3092         }
3093
3094         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3095         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3096         set_blocksize(bdev, blocksize);
3097         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3098                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3099                        "external journal");
3100                 goto out_bdev;
3101         }
3102
3103         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3104         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3105             !(le32_to_cpu(es->s_feature_incompat) &
3106               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3107                 ext4_msg(sb, KERN_ERR, "external journal has "
3108                                         "bad superblock");
3109                 brelse(bh);
3110                 goto out_bdev;
3111         }
3112
3113         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3114                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3115                 brelse(bh);
3116                 goto out_bdev;
3117         }
3118
3119         len = ext4_blocks_count(es);
3120         start = sb_block + 1;
3121         brelse(bh);     /* we're done with the superblock */
3122
3123         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3124                                         start, len, blocksize);
3125         if (!journal) {
3126                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3127                 goto out_bdev;
3128         }
3129         journal->j_private = sb;
3130         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3131         wait_on_buffer(journal->j_sb_buffer);
3132         if (!buffer_uptodate(journal->j_sb_buffer)) {
3133                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3134                 goto out_journal;
3135         }
3136         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3137                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3138                                         "user (unsupported) - %d",
3139                         be32_to_cpu(journal->j_superblock->s_nr_users));
3140                 goto out_journal;
3141         }
3142         EXT4_SB(sb)->journal_bdev = bdev;
3143         ext4_init_journal_params(sb, journal);
3144         return journal;
3145
3146 out_journal:
3147         jbd2_journal_destroy(journal);
3148 out_bdev:
3149         ext4_blkdev_put(bdev);
3150         return NULL;
3151 }
3152
3153 static int ext4_load_journal(struct super_block *sb,
3154                              struct ext4_super_block *es,
3155                              unsigned long journal_devnum)
3156 {
3157         journal_t *journal;
3158         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3159         dev_t journal_dev;
3160         int err = 0;
3161         int really_read_only;
3162
3163         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3164
3165         if (journal_devnum &&
3166             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3167                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3168                         "numbers have changed");
3169                 journal_dev = new_decode_dev(journal_devnum);
3170         } else
3171                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3172
3173         really_read_only = bdev_read_only(sb->s_bdev);
3174
3175         /*
3176          * Are we loading a blank journal or performing recovery after a
3177          * crash?  For recovery, we need to check in advance whether we
3178          * can get read-write access to the device.
3179          */
3180         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3181                 if (sb->s_flags & MS_RDONLY) {
3182                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3183                                         "required on readonly filesystem");
3184                         if (really_read_only) {
3185                                 ext4_msg(sb, KERN_ERR, "write access "
3186                                         "unavailable, cannot proceed");
3187                                 return -EROFS;
3188                         }
3189                         ext4_msg(sb, KERN_INFO, "write access will "
3190                                "be enabled during recovery");
3191                 }
3192         }
3193
3194         if (journal_inum && journal_dev) {
3195                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3196                        "and inode journals!");
3197                 return -EINVAL;
3198         }
3199
3200         if (journal_inum) {
3201                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3202                         return -EINVAL;
3203         } else {
3204                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3205                         return -EINVAL;
3206         }
3207
3208         if (!(journal->j_flags & JBD2_BARRIER))
3209                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3210
3211         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3212                 err = jbd2_journal_update_format(journal);
3213                 if (err)  {
3214                         ext4_msg(sb, KERN_ERR, "error updating journal");
3215                         jbd2_journal_destroy(journal);
3216                         return err;
3217                 }
3218         }
3219
3220         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3221                 err = jbd2_journal_wipe(journal, !really_read_only);
3222         if (!err)
3223                 err = jbd2_journal_load(journal);
3224
3225         if (err) {
3226                 ext4_msg(sb, KERN_ERR, "error loading journal");
3227                 jbd2_journal_destroy(journal);
3228                 return err;
3229         }
3230
3231         EXT4_SB(sb)->s_journal = journal;
3232         ext4_clear_journal_err(sb, es);
3233
3234         if (journal_devnum &&
3235             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3236                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3237
3238                 /* Make sure we flush the recovery flag to disk. */
3239                 ext4_commit_super(sb, 1);
3240         }
3241
3242         return 0;
3243 }
3244
3245 static int ext4_commit_super(struct super_block *sb, int sync)
3246 {
3247         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3248         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3249         int error = 0;
3250
3251         if (!sbh)
3252                 return error;
3253         if (buffer_write_io_error(sbh)) {
3254                 /*
3255                  * Oh, dear.  A previous attempt to write the
3256                  * superblock failed.  This could happen because the
3257                  * USB device was yanked out.  Or it could happen to
3258                  * be a transient write error and maybe the block will
3259                  * be remapped.  Nothing we can do but to retry the
3260                  * write and hope for the best.
3261                  */
3262                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3263                        "superblock detected");
3264                 clear_buffer_write_io_err