10483fa7c05c1289fe436810bf2361c4573f9714
[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         ext4_release_system_zone(sb);
607         ext4_mb_release(sb);
608         ext4_ext_release(sb);
609         ext4_xattr_put_super(sb);
610         if (sbi->s_journal) {
611                 err = jbd2_journal_destroy(sbi->s_journal);
612                 sbi->s_journal = NULL;
613                 if (err < 0)
614                         ext4_abort(sb, __func__,
615                                    "Couldn't clean up the journal");
616         }
617         if (!(sb->s_flags & MS_RDONLY)) {
618                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
619                 es->s_state = cpu_to_le16(sbi->s_mount_state);
620                 ext4_commit_super(sb, 1);
621         }
622         if (sbi->s_proc) {
623                 remove_proc_entry(sb->s_id, ext4_proc_root);
624         }
625         kobject_del(&sbi->s_kobj);
626
627         for (i = 0; i < sbi->s_gdb_count; i++)
628                 brelse(sbi->s_group_desc[i]);
629         kfree(sbi->s_group_desc);
630         if (is_vmalloc_addr(sbi->s_flex_groups))
631                 vfree(sbi->s_flex_groups);
632         else
633                 kfree(sbi->s_flex_groups);
634         percpu_counter_destroy(&sbi->s_freeblocks_counter);
635         percpu_counter_destroy(&sbi->s_freeinodes_counter);
636         percpu_counter_destroy(&sbi->s_dirs_counter);
637         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
638         brelse(sbi->s_sbh);
639 #ifdef CONFIG_QUOTA
640         for (i = 0; i < MAXQUOTAS; i++)
641                 kfree(sbi->s_qf_names[i]);
642 #endif
643
644         /* Debugging code just in case the in-memory inode orphan list
645          * isn't empty.  The on-disk one can be non-empty if we've
646          * detected an error and taken the fs readonly, but the
647          * in-memory list had better be clean by this point. */
648         if (!list_empty(&sbi->s_orphan))
649                 dump_orphan_list(sb, sbi);
650         J_ASSERT(list_empty(&sbi->s_orphan));
651
652         invalidate_bdev(sb->s_bdev);
653         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
654                 /*
655                  * Invalidate the journal device's buffers.  We don't want them
656                  * floating about in memory - the physical journal device may
657                  * hotswapped, and it breaks the `ro-after' testing code.
658                  */
659                 sync_blockdev(sbi->journal_bdev);
660                 invalidate_bdev(sbi->journal_bdev);
661                 ext4_blkdev_remove(sbi);
662         }
663         sb->s_fs_info = NULL;
664         /*
665          * Now that we are completely done shutting down the
666          * superblock, we need to actually destroy the kobject.
667          */
668         unlock_kernel();
669         unlock_super(sb);
670         kobject_put(&sbi->s_kobj);
671         wait_for_completion(&sbi->s_kobj_unregister);
672         kfree(sbi->s_blockgroup_lock);
673         kfree(sbi);
674 }
675
676 static struct kmem_cache *ext4_inode_cachep;
677
678 /*
679  * Called inside transaction, so use GFP_NOFS
680  */
681 static struct inode *ext4_alloc_inode(struct super_block *sb)
682 {
683         struct ext4_inode_info *ei;
684
685         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
686         if (!ei)
687                 return NULL;
688
689         ei->vfs_inode.i_version = 1;
690         ei->vfs_inode.i_data.writeback_index = 0;
691         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
692         INIT_LIST_HEAD(&ei->i_prealloc_list);
693         spin_lock_init(&ei->i_prealloc_lock);
694         /*
695          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
696          * therefore it can be null here.  Don't check it, just initialize
697          * jinode.
698          */
699         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
700         ei->i_reserved_data_blocks = 0;
701         ei->i_reserved_meta_blocks = 0;
702         ei->i_allocated_meta_blocks = 0;
703         ei->i_delalloc_reserved_flag = 0;
704         spin_lock_init(&(ei->i_block_reservation_lock));
705         INIT_LIST_HEAD(&ei->i_aio_dio_complete_list);
706         ei->cur_aio_dio = NULL;
707
708         return &ei->vfs_inode;
709 }
710
711 static void ext4_destroy_inode(struct inode *inode)
712 {
713         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
714                 ext4_msg(inode->i_sb, KERN_ERR,
715                          "Inode %lu (%p): orphan list check failed!",
716                          inode->i_ino, EXT4_I(inode));
717                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
718                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
719                                 true);
720                 dump_stack();
721         }
722         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
723 }
724
725 static void init_once(void *foo)
726 {
727         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
728
729         INIT_LIST_HEAD(&ei->i_orphan);
730 #ifdef CONFIG_EXT4_FS_XATTR
731         init_rwsem(&ei->xattr_sem);
732 #endif
733         init_rwsem(&ei->i_data_sem);
734         inode_init_once(&ei->vfs_inode);
735 }
736
737 static int init_inodecache(void)
738 {
739         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
740                                              sizeof(struct ext4_inode_info),
741                                              0, (SLAB_RECLAIM_ACCOUNT|
742                                                 SLAB_MEM_SPREAD),
743                                              init_once);
744         if (ext4_inode_cachep == NULL)
745                 return -ENOMEM;
746         return 0;
747 }
748
749 static void destroy_inodecache(void)
750 {
751         kmem_cache_destroy(ext4_inode_cachep);
752 }
753
754 static void ext4_clear_inode(struct inode *inode)
755 {
756         ext4_discard_preallocations(inode);
757         if (EXT4_JOURNAL(inode))
758                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
759                                        &EXT4_I(inode)->jinode);
760 }
761
762 static inline void ext4_show_quota_options(struct seq_file *seq,
763                                            struct super_block *sb)
764 {
765 #if defined(CONFIG_QUOTA)
766         struct ext4_sb_info *sbi = EXT4_SB(sb);
767
768         if (sbi->s_jquota_fmt) {
769                 char *fmtname = "";
770
771                 switch (sbi->s_jquota_fmt) {
772                 case QFMT_VFS_OLD:
773                         fmtname = "vfsold";
774                         break;
775                 case QFMT_VFS_V0:
776                         fmtname = "vfsv0";
777                         break;
778                 case QFMT_VFS_V1:
779                         fmtname = "vfsv1";
780                         break;
781                 }
782                 seq_printf(seq, ",jqfmt=%s", fmtname);
783         }
784
785         if (sbi->s_qf_names[USRQUOTA])
786                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
787
788         if (sbi->s_qf_names[GRPQUOTA])
789                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
790
791         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
792                 seq_puts(seq, ",usrquota");
793
794         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
795                 seq_puts(seq, ",grpquota");
796 #endif
797 }
798
799 /*
800  * Show an option if
801  *  - it's set to a non-default value OR
802  *  - if the per-sb default is different from the global default
803  */
804 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
805 {
806         int def_errors;
807         unsigned long def_mount_opts;
808         struct super_block *sb = vfs->mnt_sb;
809         struct ext4_sb_info *sbi = EXT4_SB(sb);
810         struct ext4_super_block *es = sbi->s_es;
811
812         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
813         def_errors     = le16_to_cpu(es->s_errors);
814
815         if (sbi->s_sb_block != 1)
816                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
817         if (test_opt(sb, MINIX_DF))
818                 seq_puts(seq, ",minixdf");
819         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
820                 seq_puts(seq, ",grpid");
821         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
822                 seq_puts(seq, ",nogrpid");
823         if (sbi->s_resuid != EXT4_DEF_RESUID ||
824             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
825                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
826         }
827         if (sbi->s_resgid != EXT4_DEF_RESGID ||
828             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
829                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
830         }
831         if (test_opt(sb, ERRORS_RO)) {
832                 if (def_errors == EXT4_ERRORS_PANIC ||
833                     def_errors == EXT4_ERRORS_CONTINUE) {
834                         seq_puts(seq, ",errors=remount-ro");
835                 }
836         }
837         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
838                 seq_puts(seq, ",errors=continue");
839         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
840                 seq_puts(seq, ",errors=panic");
841         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
842                 seq_puts(seq, ",nouid32");
843         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
844                 seq_puts(seq, ",debug");
845         if (test_opt(sb, OLDALLOC))
846                 seq_puts(seq, ",oldalloc");
847 #ifdef CONFIG_EXT4_FS_XATTR
848         if (test_opt(sb, XATTR_USER) &&
849                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
850                 seq_puts(seq, ",user_xattr");
851         if (!test_opt(sb, XATTR_USER) &&
852             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
853                 seq_puts(seq, ",nouser_xattr");
854         }
855 #endif
856 #ifdef CONFIG_EXT4_FS_POSIX_ACL
857         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
858                 seq_puts(seq, ",acl");
859         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
860                 seq_puts(seq, ",noacl");
861 #endif
862         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
863                 seq_printf(seq, ",commit=%u",
864                            (unsigned) (sbi->s_commit_interval / HZ));
865         }
866         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
867                 seq_printf(seq, ",min_batch_time=%u",
868                            (unsigned) sbi->s_min_batch_time);
869         }
870         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
871                 seq_printf(seq, ",max_batch_time=%u",
872                            (unsigned) sbi->s_min_batch_time);
873         }
874
875         /*
876          * We're changing the default of barrier mount option, so
877          * let's always display its mount state so it's clear what its
878          * status is.
879          */
880         seq_puts(seq, ",barrier=");
881         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
882         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
883                 seq_puts(seq, ",journal_async_commit");
884         if (test_opt(sb, NOBH))
885                 seq_puts(seq, ",nobh");
886         if (test_opt(sb, I_VERSION))
887                 seq_puts(seq, ",i_version");
888         if (!test_opt(sb, DELALLOC))
889                 seq_puts(seq, ",nodelalloc");
890
891
892         if (sbi->s_stripe)
893                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
894         /*
895          * journal mode get enabled in different ways
896          * So just print the value even if we didn't specify it
897          */
898         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
899                 seq_puts(seq, ",data=journal");
900         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
901                 seq_puts(seq, ",data=ordered");
902         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
903                 seq_puts(seq, ",data=writeback");
904
905         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
906                 seq_printf(seq, ",inode_readahead_blks=%u",
907                            sbi->s_inode_readahead_blks);
908
909         if (test_opt(sb, DATA_ERR_ABORT))
910                 seq_puts(seq, ",data_err=abort");
911
912         if (test_opt(sb, NO_AUTO_DA_ALLOC))
913                 seq_puts(seq, ",noauto_da_alloc");
914
915         ext4_show_quota_options(seq, sb);
916
917         return 0;
918 }
919
920 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
921                                         u64 ino, u32 generation)
922 {
923         struct inode *inode;
924
925         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
926                 return ERR_PTR(-ESTALE);
927         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
928                 return ERR_PTR(-ESTALE);
929
930         /* iget isn't really right if the inode is currently unallocated!!
931          *
932          * ext4_read_inode will return a bad_inode if the inode had been
933          * deleted, so we should be safe.
934          *
935          * Currently we don't know the generation for parent directory, so
936          * a generation of 0 means "accept any"
937          */
938         inode = ext4_iget(sb, ino);
939         if (IS_ERR(inode))
940                 return ERR_CAST(inode);
941         if (generation && inode->i_generation != generation) {
942                 iput(inode);
943                 return ERR_PTR(-ESTALE);
944         }
945
946         return inode;
947 }
948
949 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
950                                         int fh_len, int fh_type)
951 {
952         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
953                                     ext4_nfs_get_inode);
954 }
955
956 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
957                                         int fh_len, int fh_type)
958 {
959         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
960                                     ext4_nfs_get_inode);
961 }
962
963 /*
964  * Try to release metadata pages (indirect blocks, directories) which are
965  * mapped via the block device.  Since these pages could have journal heads
966  * which would prevent try_to_free_buffers() from freeing them, we must use
967  * jbd2 layer's try_to_free_buffers() function to release them.
968  */
969 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
970                                  gfp_t wait)
971 {
972         journal_t *journal = EXT4_SB(sb)->s_journal;
973
974         WARN_ON(PageChecked(page));
975         if (!page_has_buffers(page))
976                 return 0;
977         if (journal)
978                 return jbd2_journal_try_to_free_buffers(journal, page,
979                                                         wait & ~__GFP_WAIT);
980         return try_to_free_buffers(page);
981 }
982
983 #ifdef CONFIG_QUOTA
984 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
985 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
986
987 static int ext4_write_dquot(struct dquot *dquot);
988 static int ext4_acquire_dquot(struct dquot *dquot);
989 static int ext4_release_dquot(struct dquot *dquot);
990 static int ext4_mark_dquot_dirty(struct dquot *dquot);
991 static int ext4_write_info(struct super_block *sb, int type);
992 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
993                                 char *path, int remount);
994 static int ext4_quota_on_mount(struct super_block *sb, int type);
995 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
996                                size_t len, loff_t off);
997 static ssize_t ext4_quota_write(struct super_block *sb, int type,
998                                 const char *data, size_t len, loff_t off);
999
1000 static const struct dquot_operations ext4_quota_operations = {
1001         .initialize     = dquot_initialize,
1002         .drop           = dquot_drop,
1003         .alloc_space    = dquot_alloc_space,
1004         .reserve_space  = dquot_reserve_space,
1005         .claim_space    = dquot_claim_space,
1006         .release_rsv    = dquot_release_reserved_space,
1007         .get_reserved_space = ext4_get_reserved_space,
1008         .alloc_inode    = dquot_alloc_inode,
1009         .free_space     = dquot_free_space,
1010         .free_inode     = dquot_free_inode,
1011         .transfer       = dquot_transfer,
1012         .write_dquot    = ext4_write_dquot,
1013         .acquire_dquot  = ext4_acquire_dquot,
1014         .release_dquot  = ext4_release_dquot,
1015         .mark_dirty     = ext4_mark_dquot_dirty,
1016         .write_info     = ext4_write_info,
1017         .alloc_dquot    = dquot_alloc,
1018         .destroy_dquot  = dquot_destroy,
1019 };
1020
1021 static const struct quotactl_ops ext4_qctl_operations = {
1022         .quota_on       = ext4_quota_on,
1023         .quota_off      = vfs_quota_off,
1024         .quota_sync     = vfs_quota_sync,
1025         .get_info       = vfs_get_dqinfo,
1026         .set_info       = vfs_set_dqinfo,
1027         .get_dqblk      = vfs_get_dqblk,
1028         .set_dqblk      = vfs_set_dqblk
1029 };
1030 #endif
1031
1032 static const struct super_operations ext4_sops = {
1033         .alloc_inode    = ext4_alloc_inode,
1034         .destroy_inode  = ext4_destroy_inode,
1035         .write_inode    = ext4_write_inode,
1036         .dirty_inode    = ext4_dirty_inode,
1037         .delete_inode   = ext4_delete_inode,
1038         .put_super      = ext4_put_super,
1039         .sync_fs        = ext4_sync_fs,
1040         .freeze_fs      = ext4_freeze,
1041         .unfreeze_fs    = ext4_unfreeze,
1042         .statfs         = ext4_statfs,
1043         .remount_fs     = ext4_remount,
1044         .clear_inode    = ext4_clear_inode,
1045         .show_options   = ext4_show_options,
1046 #ifdef CONFIG_QUOTA
1047         .quota_read     = ext4_quota_read,
1048         .quota_write    = ext4_quota_write,
1049 #endif
1050         .bdev_try_to_free_page = bdev_try_to_free_page,
1051 };
1052
1053 static const struct super_operations ext4_nojournal_sops = {
1054         .alloc_inode    = ext4_alloc_inode,
1055         .destroy_inode  = ext4_destroy_inode,
1056         .write_inode    = ext4_write_inode,
1057         .dirty_inode    = ext4_dirty_inode,
1058         .delete_inode   = ext4_delete_inode,
1059         .write_super    = ext4_write_super,
1060         .put_super      = ext4_put_super,
1061         .statfs         = ext4_statfs,
1062         .remount_fs     = ext4_remount,
1063         .clear_inode    = ext4_clear_inode,
1064         .show_options   = ext4_show_options,
1065 #ifdef CONFIG_QUOTA
1066         .quota_read     = ext4_quota_read,
1067         .quota_write    = ext4_quota_write,
1068 #endif
1069         .bdev_try_to_free_page = bdev_try_to_free_page,
1070 };
1071
1072 static const struct export_operations ext4_export_ops = {
1073         .fh_to_dentry = ext4_fh_to_dentry,
1074         .fh_to_parent = ext4_fh_to_parent,
1075         .get_parent = ext4_get_parent,
1076 };
1077
1078 enum {
1079         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1080         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1081         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1082         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1083         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1084         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1085         Opt_journal_update, Opt_journal_dev,
1086         Opt_journal_checksum, Opt_journal_async_commit,
1087         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1088         Opt_data_err_abort, Opt_data_err_ignore,
1089         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1090         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1091         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1092         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1093         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1094         Opt_block_validity, Opt_noblock_validity,
1095         Opt_inode_readahead_blks, Opt_journal_ioprio
1096 };
1097
1098 static const match_table_t tokens = {
1099         {Opt_bsd_df, "bsddf"},
1100         {Opt_minix_df, "minixdf"},
1101         {Opt_grpid, "grpid"},
1102         {Opt_grpid, "bsdgroups"},
1103         {Opt_nogrpid, "nogrpid"},
1104         {Opt_nogrpid, "sysvgroups"},
1105         {Opt_resgid, "resgid=%u"},
1106         {Opt_resuid, "resuid=%u"},
1107         {Opt_sb, "sb=%u"},
1108         {Opt_err_cont, "errors=continue"},
1109         {Opt_err_panic, "errors=panic"},
1110         {Opt_err_ro, "errors=remount-ro"},
1111         {Opt_nouid32, "nouid32"},
1112         {Opt_debug, "debug"},
1113         {Opt_oldalloc, "oldalloc"},
1114         {Opt_orlov, "orlov"},
1115         {Opt_user_xattr, "user_xattr"},
1116         {Opt_nouser_xattr, "nouser_xattr"},
1117         {Opt_acl, "acl"},
1118         {Opt_noacl, "noacl"},
1119         {Opt_noload, "noload"},
1120         {Opt_nobh, "nobh"},
1121         {Opt_bh, "bh"},
1122         {Opt_commit, "commit=%u"},
1123         {Opt_min_batch_time, "min_batch_time=%u"},
1124         {Opt_max_batch_time, "max_batch_time=%u"},
1125         {Opt_journal_update, "journal=update"},
1126         {Opt_journal_dev, "journal_dev=%u"},
1127         {Opt_journal_checksum, "journal_checksum"},
1128         {Opt_journal_async_commit, "journal_async_commit"},
1129         {Opt_abort, "abort"},
1130         {Opt_data_journal, "data=journal"},
1131         {Opt_data_ordered, "data=ordered"},
1132         {Opt_data_writeback, "data=writeback"},
1133         {Opt_data_err_abort, "data_err=abort"},
1134         {Opt_data_err_ignore, "data_err=ignore"},
1135         {Opt_offusrjquota, "usrjquota="},
1136         {Opt_usrjquota, "usrjquota=%s"},
1137         {Opt_offgrpjquota, "grpjquota="},
1138         {Opt_grpjquota, "grpjquota=%s"},
1139         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1140         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1141         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1142         {Opt_grpquota, "grpquota"},
1143         {Opt_noquota, "noquota"},
1144         {Opt_quota, "quota"},
1145         {Opt_usrquota, "usrquota"},
1146         {Opt_barrier, "barrier=%u"},
1147         {Opt_barrier, "barrier"},
1148         {Opt_nobarrier, "nobarrier"},
1149         {Opt_i_version, "i_version"},
1150         {Opt_stripe, "stripe=%u"},
1151         {Opt_resize, "resize"},
1152         {Opt_delalloc, "delalloc"},
1153         {Opt_nodelalloc, "nodelalloc"},
1154         {Opt_block_validity, "block_validity"},
1155         {Opt_noblock_validity, "noblock_validity"},
1156         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1157         {Opt_journal_ioprio, "journal_ioprio=%u"},
1158         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1159         {Opt_auto_da_alloc, "auto_da_alloc"},
1160         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1161         {Opt_err, NULL},
1162 };
1163
1164 static ext4_fsblk_t get_sb_block(void **data)
1165 {
1166         ext4_fsblk_t    sb_block;
1167         char            *options = (char *) *data;
1168
1169         if (!options || strncmp(options, "sb=", 3) != 0)
1170                 return 1;       /* Default location */
1171
1172         options += 3;
1173         /* TODO: use simple_strtoll with >32bit ext4 */
1174         sb_block = simple_strtoul(options, &options, 0);
1175         if (*options && *options != ',') {
1176                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1177                        (char *) *data);
1178                 return 1;
1179         }
1180         if (*options == ',')
1181                 options++;
1182         *data = (void *) options;
1183
1184         return sb_block;
1185 }
1186
1187 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1188
1189 static int parse_options(char *options, struct super_block *sb,
1190                          unsigned long *journal_devnum,
1191                          unsigned int *journal_ioprio,
1192                          ext4_fsblk_t *n_blocks_count, int is_remount)
1193 {
1194         struct ext4_sb_info *sbi = EXT4_SB(sb);
1195         char *p;
1196         substring_t args[MAX_OPT_ARGS];
1197         int data_opt = 0;
1198         int option;
1199 #ifdef CONFIG_QUOTA
1200         int qtype, qfmt;
1201         char *qname;
1202 #endif
1203
1204         if (!options)
1205                 return 1;
1206
1207         while ((p = strsep(&options, ",")) != NULL) {
1208                 int token;
1209                 if (!*p)
1210                         continue;
1211
1212                 token = match_token(p, tokens, args);
1213                 switch (token) {
1214                 case Opt_bsd_df:
1215                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1216                         break;
1217                 case Opt_minix_df:
1218                         set_opt(sbi->s_mount_opt, MINIX_DF);
1219                         break;
1220                 case Opt_grpid:
1221                         set_opt(sbi->s_mount_opt, GRPID);
1222                         break;
1223                 case Opt_nogrpid:
1224                         clear_opt(sbi->s_mount_opt, GRPID);
1225                         break;
1226                 case Opt_resuid:
1227                         if (match_int(&args[0], &option))
1228                                 return 0;
1229                         sbi->s_resuid = option;
1230                         break;
1231                 case Opt_resgid:
1232                         if (match_int(&args[0], &option))
1233                                 return 0;
1234                         sbi->s_resgid = option;
1235                         break;
1236                 case Opt_sb:
1237                         /* handled by get_sb_block() instead of here */
1238                         /* *sb_block = match_int(&args[0]); */
1239                         break;
1240                 case Opt_err_panic:
1241                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1242                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1243                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1244                         break;
1245                 case Opt_err_ro:
1246                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1247                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1248                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1249                         break;
1250                 case Opt_err_cont:
1251                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1252                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1253                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1254                         break;
1255                 case Opt_nouid32:
1256                         set_opt(sbi->s_mount_opt, NO_UID32);
1257                         break;
1258                 case Opt_debug:
1259                         set_opt(sbi->s_mount_opt, DEBUG);
1260                         break;
1261                 case Opt_oldalloc:
1262                         set_opt(sbi->s_mount_opt, OLDALLOC);
1263                         break;
1264                 case Opt_orlov:
1265                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1266                         break;
1267 #ifdef CONFIG_EXT4_FS_XATTR
1268                 case Opt_user_xattr:
1269                         set_opt(sbi->s_mount_opt, XATTR_USER);
1270                         break;
1271                 case Opt_nouser_xattr:
1272                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1273                         break;
1274 #else
1275                 case Opt_user_xattr:
1276                 case Opt_nouser_xattr:
1277                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1278                         break;
1279 #endif
1280 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1281                 case Opt_acl:
1282                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1283                         break;
1284                 case Opt_noacl:
1285                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1286                         break;
1287 #else
1288                 case Opt_acl:
1289                 case Opt_noacl:
1290                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1291                         break;
1292 #endif
1293                 case Opt_journal_update:
1294                         /* @@@ FIXME */
1295                         /* Eventually we will want to be able to create
1296                            a journal file here.  For now, only allow the
1297                            user to specify an existing inode to be the
1298                            journal file. */
1299                         if (is_remount) {
1300                                 ext4_msg(sb, KERN_ERR,
1301                                          "Cannot specify journal on remount");
1302                                 return 0;
1303                         }
1304                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1305                         break;
1306                 case Opt_journal_dev:
1307                         if (is_remount) {
1308                                 ext4_msg(sb, KERN_ERR,
1309                                         "Cannot specify journal on remount");
1310                                 return 0;
1311                         }
1312                         if (match_int(&args[0], &option))
1313                                 return 0;
1314                         *journal_devnum = option;
1315                         break;
1316                 case Opt_journal_checksum:
1317                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1318                         break;
1319                 case Opt_journal_async_commit:
1320                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1321                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1322                         break;
1323                 case Opt_noload:
1324                         set_opt(sbi->s_mount_opt, NOLOAD);
1325                         break;
1326                 case Opt_commit:
1327                         if (match_int(&args[0], &option))
1328                                 return 0;
1329                         if (option < 0)
1330                                 return 0;
1331                         if (option == 0)
1332                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1333                         sbi->s_commit_interval = HZ * option;
1334                         break;
1335                 case Opt_max_batch_time:
1336                         if (match_int(&args[0], &option))
1337                                 return 0;
1338                         if (option < 0)
1339                                 return 0;
1340                         if (option == 0)
1341                                 option = EXT4_DEF_MAX_BATCH_TIME;
1342                         sbi->s_max_batch_time = option;
1343                         break;
1344                 case Opt_min_batch_time:
1345                         if (match_int(&args[0], &option))
1346                                 return 0;
1347                         if (option < 0)
1348                                 return 0;
1349                         sbi->s_min_batch_time = option;
1350                         break;
1351                 case Opt_data_journal:
1352                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1353                         goto datacheck;
1354                 case Opt_data_ordered:
1355                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1356                         goto datacheck;
1357                 case Opt_data_writeback:
1358                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1359                 datacheck:
1360                         if (is_remount) {
1361                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1362                                                 != data_opt) {
1363                                         ext4_msg(sb, KERN_ERR,
1364                                                 "Cannot change data mode on remount");
1365                                         return 0;
1366                                 }
1367                         } else {
1368                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1369                                 sbi->s_mount_opt |= data_opt;
1370                         }
1371                         break;
1372                 case Opt_data_err_abort:
1373                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1374                         break;
1375                 case Opt_data_err_ignore:
1376                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1377                         break;
1378 #ifdef CONFIG_QUOTA
1379                 case Opt_usrjquota:
1380                         qtype = USRQUOTA;
1381                         goto set_qf_name;
1382                 case Opt_grpjquota:
1383                         qtype = GRPQUOTA;
1384 set_qf_name:
1385                         if (sb_any_quota_loaded(sb) &&
1386                             !sbi->s_qf_names[qtype]) {
1387                                 ext4_msg(sb, KERN_ERR,
1388                                        "Cannot change journaled "
1389                                        "quota options when quota turned on");
1390                                 return 0;
1391                         }
1392                         qname = match_strdup(&args[0]);
1393                         if (!qname) {
1394                                 ext4_msg(sb, KERN_ERR,
1395                                         "Not enough memory for "
1396                                         "storing quotafile name");
1397                                 return 0;
1398                         }
1399                         if (sbi->s_qf_names[qtype] &&
1400                             strcmp(sbi->s_qf_names[qtype], qname)) {
1401                                 ext4_msg(sb, KERN_ERR,
1402                                         "%s quota file already "
1403                                         "specified", QTYPE2NAME(qtype));
1404                                 kfree(qname);
1405                                 return 0;
1406                         }
1407                         sbi->s_qf_names[qtype] = qname;
1408                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1409                                 ext4_msg(sb, KERN_ERR,
1410                                         "quotafile must be on "
1411                                         "filesystem root");
1412                                 kfree(sbi->s_qf_names[qtype]);
1413                                 sbi->s_qf_names[qtype] = NULL;
1414                                 return 0;
1415                         }
1416                         set_opt(sbi->s_mount_opt, QUOTA);
1417                         break;
1418                 case Opt_offusrjquota:
1419                         qtype = USRQUOTA;
1420                         goto clear_qf_name;
1421                 case Opt_offgrpjquota:
1422                         qtype = GRPQUOTA;
1423 clear_qf_name:
1424                         if (sb_any_quota_loaded(sb) &&
1425                             sbi->s_qf_names[qtype]) {
1426                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1427                                         "journaled quota options when "
1428                                         "quota turned on");
1429                                 return 0;
1430                         }
1431                         /*
1432                          * The space will be released later when all options
1433                          * are confirmed to be correct
1434                          */
1435                         sbi->s_qf_names[qtype] = NULL;
1436                         break;
1437                 case Opt_jqfmt_vfsold:
1438                         qfmt = QFMT_VFS_OLD;
1439                         goto set_qf_format;
1440                 case Opt_jqfmt_vfsv0:
1441                         qfmt = QFMT_VFS_V0;
1442                         goto set_qf_format;
1443                 case Opt_jqfmt_vfsv1:
1444                         qfmt = QFMT_VFS_V1;
1445 set_qf_format:
1446                         if (sb_any_quota_loaded(sb) &&
1447                             sbi->s_jquota_fmt != qfmt) {
1448                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1449                                         "journaled quota options when "
1450                                         "quota turned on");
1451                                 return 0;
1452                         }
1453                         sbi->s_jquota_fmt = qfmt;
1454                         break;
1455                 case Opt_quota:
1456                 case Opt_usrquota:
1457                         set_opt(sbi->s_mount_opt, QUOTA);
1458                         set_opt(sbi->s_mount_opt, USRQUOTA);
1459                         break;
1460                 case Opt_grpquota:
1461                         set_opt(sbi->s_mount_opt, QUOTA);
1462                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1463                         break;
1464                 case Opt_noquota:
1465                         if (sb_any_quota_loaded(sb)) {
1466                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1467                                         "options when quota turned on");
1468                                 return 0;
1469                         }
1470                         clear_opt(sbi->s_mount_opt, QUOTA);
1471                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1472                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1473                         break;
1474 #else
1475                 case Opt_quota:
1476                 case Opt_usrquota:
1477                 case Opt_grpquota:
1478                         ext4_msg(sb, KERN_ERR,
1479                                 "quota options not supported");
1480                         break;
1481                 case Opt_usrjquota:
1482                 case Opt_grpjquota:
1483                 case Opt_offusrjquota:
1484                 case Opt_offgrpjquota:
1485                 case Opt_jqfmt_vfsold:
1486                 case Opt_jqfmt_vfsv0:
1487                 case Opt_jqfmt_vfsv1:
1488                         ext4_msg(sb, KERN_ERR,
1489                                 "journaled quota options not supported");
1490                         break;
1491                 case Opt_noquota:
1492                         break;
1493 #endif
1494                 case Opt_abort:
1495                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1496                         break;
1497                 case Opt_nobarrier:
1498                         clear_opt(sbi->s_mount_opt, BARRIER);
1499                         break;
1500                 case Opt_barrier:
1501                         if (match_int(&args[0], &option)) {
1502                                 set_opt(sbi->s_mount_opt, BARRIER);
1503                                 break;
1504                         }
1505                         if (option)
1506                                 set_opt(sbi->s_mount_opt, BARRIER);
1507                         else
1508                                 clear_opt(sbi->s_mount_opt, BARRIER);
1509                         break;
1510                 case Opt_ignore:
1511                         break;
1512                 case Opt_resize:
1513                         if (!is_remount) {
1514                                 ext4_msg(sb, KERN_ERR,
1515                                         "resize option only available "
1516                                         "for remount");
1517                                 return 0;
1518                         }
1519                         if (match_int(&args[0], &option) != 0)
1520                                 return 0;
1521                         *n_blocks_count = option;
1522                         break;
1523                 case Opt_nobh:
1524                         set_opt(sbi->s_mount_opt, NOBH);
1525                         break;
1526                 case Opt_bh:
1527                         clear_opt(sbi->s_mount_opt, NOBH);
1528                         break;
1529                 case Opt_i_version:
1530                         set_opt(sbi->s_mount_opt, I_VERSION);
1531                         sb->s_flags |= MS_I_VERSION;
1532                         break;
1533                 case Opt_nodelalloc:
1534                         clear_opt(sbi->s_mount_opt, DELALLOC);
1535                         break;
1536                 case Opt_stripe:
1537                         if (match_int(&args[0], &option))
1538                                 return 0;
1539                         if (option < 0)
1540                                 return 0;
1541                         sbi->s_stripe = option;
1542                         break;
1543                 case Opt_delalloc:
1544                         set_opt(sbi->s_mount_opt, DELALLOC);
1545                         break;
1546                 case Opt_block_validity:
1547                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1548                         break;
1549                 case Opt_noblock_validity:
1550                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1551                         break;
1552                 case Opt_inode_readahead_blks:
1553                         if (match_int(&args[0], &option))
1554                                 return 0;
1555                         if (option < 0 || option > (1 << 30))
1556                                 return 0;
1557                         if (!is_power_of_2(option)) {
1558                                 ext4_msg(sb, KERN_ERR,
1559                                          "EXT4-fs: inode_readahead_blks"
1560                                          " must be a power of 2");
1561                                 return 0;
1562                         }
1563                         sbi->s_inode_readahead_blks = option;
1564                         break;
1565                 case Opt_journal_ioprio:
1566                         if (match_int(&args[0], &option))
1567                                 return 0;
1568                         if (option < 0 || option > 7)
1569                                 break;
1570                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1571                                                             option);
1572                         break;
1573                 case Opt_noauto_da_alloc:
1574                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1575                         break;
1576                 case Opt_auto_da_alloc:
1577                         if (match_int(&args[0], &option)) {
1578                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1579                                 break;
1580                         }
1581                         if (option)
1582                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1583                         else
1584                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1585                         break;
1586                 default:
1587                         ext4_msg(sb, KERN_ERR,
1588                                "Unrecognized mount option \"%s\" "
1589                                "or missing value", p);
1590                         return 0;
1591                 }
1592         }
1593 #ifdef CONFIG_QUOTA
1594         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1595                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1596                      sbi->s_qf_names[USRQUOTA])
1597                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1598
1599                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1600                      sbi->s_qf_names[GRPQUOTA])
1601                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1602
1603                 if ((sbi->s_qf_names[USRQUOTA] &&
1604                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1605                     (sbi->s_qf_names[GRPQUOTA] &&
1606                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1607                         ext4_msg(sb, KERN_ERR, "old and new quota "
1608                                         "format mixing");
1609                         return 0;
1610                 }
1611
1612                 if (!sbi->s_jquota_fmt) {
1613                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1614                                         "not specified");
1615                         return 0;
1616                 }
1617         } else {
1618                 if (sbi->s_jquota_fmt) {
1619                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1620                                         "specified with no journaling "
1621                                         "enabled");
1622                         return 0;
1623                 }
1624         }
1625 #endif
1626         return 1;
1627 }
1628
1629 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1630                             int read_only)
1631 {
1632         struct ext4_sb_info *sbi = EXT4_SB(sb);
1633         int res = 0;
1634
1635         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1636                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1637                          "forcing read-only mode");
1638                 res = MS_RDONLY;
1639         }
1640         if (read_only)
1641                 return res;
1642         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1643                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1644                          "running e2fsck is recommended");
1645         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1646                 ext4_msg(sb, KERN_WARNING,
1647                          "warning: mounting fs with errors, "
1648                          "running e2fsck is recommended");
1649         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1650                  le16_to_cpu(es->s_mnt_count) >=
1651                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1652                 ext4_msg(sb, KERN_WARNING,
1653                          "warning: maximal mount count reached, "
1654                          "running e2fsck is recommended");
1655         else if (le32_to_cpu(es->s_checkinterval) &&
1656                 (le32_to_cpu(es->s_lastcheck) +
1657                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1658                 ext4_msg(sb, KERN_WARNING,
1659                          "warning: checktime reached, "
1660                          "running e2fsck is recommended");
1661         if (!sbi->s_journal)
1662                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1663         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1664                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1665         le16_add_cpu(&es->s_mnt_count, 1);
1666         es->s_mtime = cpu_to_le32(get_seconds());
1667         ext4_update_dynamic_rev(sb);
1668         if (sbi->s_journal)
1669                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1670
1671         ext4_commit_super(sb, 1);
1672         if (test_opt(sb, DEBUG))
1673                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1674                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1675                         sb->s_blocksize,
1676                         sbi->s_groups_count,
1677                         EXT4_BLOCKS_PER_GROUP(sb),
1678                         EXT4_INODES_PER_GROUP(sb),
1679                         sbi->s_mount_opt);
1680
1681         return res;
1682 }
1683
1684 static int ext4_fill_flex_info(struct super_block *sb)
1685 {
1686         struct ext4_sb_info *sbi = EXT4_SB(sb);
1687         struct ext4_group_desc *gdp = NULL;
1688         ext4_group_t flex_group_count;
1689         ext4_group_t flex_group;
1690         int groups_per_flex = 0;
1691         size_t size;
1692         int i;
1693
1694         if (!sbi->s_es->s_log_groups_per_flex) {
1695                 sbi->s_log_groups_per_flex = 0;
1696                 return 1;
1697         }
1698
1699         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1700         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1701
1702         /* We allocate both existing and potentially added groups */
1703         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1704                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1705                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1706         size = flex_group_count * sizeof(struct flex_groups);
1707         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1708         if (sbi->s_flex_groups == NULL) {
1709                 sbi->s_flex_groups = vmalloc(size);
1710                 if (sbi->s_flex_groups)
1711                         memset(sbi->s_flex_groups, 0, size);
1712         }
1713         if (sbi->s_flex_groups == NULL) {
1714                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1715                                 "%u flex groups", flex_group_count);
1716                 goto failed;
1717         }
1718
1719         for (i = 0; i < sbi->s_groups_count; i++) {
1720                 gdp = ext4_get_group_desc(sb, i, NULL);
1721
1722                 flex_group = ext4_flex_group(sbi, i);
1723                 atomic_add(ext4_free_inodes_count(sb, gdp),
1724                            &sbi->s_flex_groups[flex_group].free_inodes);
1725                 atomic_add(ext4_free_blks_count(sb, gdp),
1726                            &sbi->s_flex_groups[flex_group].free_blocks);
1727                 atomic_add(ext4_used_dirs_count(sb, gdp),
1728                            &sbi->s_flex_groups[flex_group].used_dirs);
1729         }
1730
1731         return 1;
1732 failed:
1733         return 0;
1734 }
1735
1736 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1737                             struct ext4_group_desc *gdp)
1738 {
1739         __u16 crc = 0;
1740
1741         if (sbi->s_es->s_feature_ro_compat &
1742             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1743                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1744                 __le32 le_group = cpu_to_le32(block_group);
1745
1746                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1747                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1748                 crc = crc16(crc, (__u8 *)gdp, offset);
1749                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1750                 /* for checksum of struct ext4_group_desc do the rest...*/
1751                 if ((sbi->s_es->s_feature_incompat &
1752                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1753                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1754                         crc = crc16(crc, (__u8 *)gdp + offset,
1755                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1756                                         offset);
1757         }
1758
1759         return cpu_to_le16(crc);
1760 }
1761
1762 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1763                                 struct ext4_group_desc *gdp)
1764 {
1765         if ((sbi->s_es->s_feature_ro_compat &
1766              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1767             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1768                 return 0;
1769
1770         return 1;
1771 }
1772
1773 /* Called at mount-time, super-block is locked */
1774 static int ext4_check_descriptors(struct super_block *sb)
1775 {
1776         struct ext4_sb_info *sbi = EXT4_SB(sb);
1777         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1778         ext4_fsblk_t last_block;
1779         ext4_fsblk_t block_bitmap;
1780         ext4_fsblk_t inode_bitmap;
1781         ext4_fsblk_t inode_table;
1782         int flexbg_flag = 0;
1783         ext4_group_t i;
1784
1785         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1786                 flexbg_flag = 1;
1787
1788         ext4_debug("Checking group descriptors");
1789
1790         for (i = 0; i < sbi->s_groups_count; i++) {
1791                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1792
1793                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1794                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1795                 else
1796                         last_block = first_block +
1797                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1798
1799                 block_bitmap = ext4_block_bitmap(sb, gdp);
1800                 if (block_bitmap < first_block || block_bitmap > last_block) {
1801                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1802                                "Block bitmap for group %u not in group "
1803                                "(block %llu)!", i, block_bitmap);
1804                         return 0;
1805                 }
1806                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1807                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1808                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1809                                "Inode bitmap for group %u not in group "
1810                                "(block %llu)!", i, inode_bitmap);
1811                         return 0;
1812                 }
1813                 inode_table = ext4_inode_table(sb, gdp);
1814                 if (inode_table < first_block ||
1815                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1816                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1817                                "Inode table for group %u not in group "
1818                                "(block %llu)!", i, inode_table);
1819                         return 0;
1820                 }
1821                 ext4_lock_group(sb, i);
1822                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1823                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1824                                  "Checksum for group %u failed (%u!=%u)",
1825                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1826                                      gdp)), le16_to_cpu(gdp->bg_checksum));
1827                         if (!(sb->s_flags & MS_RDONLY)) {
1828                                 ext4_unlock_group(sb, i);
1829                                 return 0;
1830                         }
1831                 }
1832                 ext4_unlock_group(sb, i);
1833                 if (!flexbg_flag)
1834                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1835         }
1836
1837         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1838         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1839         return 1;
1840 }
1841
1842 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1843  * the superblock) which were deleted from all directories, but held open by
1844  * a process at the time of a crash.  We walk the list and try to delete these
1845  * inodes at recovery time (only with a read-write filesystem).
1846  *
1847  * In order to keep the orphan inode chain consistent during traversal (in
1848  * case of crash during recovery), we link each inode into the superblock
1849  * orphan list_head and handle it the same way as an inode deletion during
1850  * normal operation (which journals the operations for us).
1851  *
1852  * We only do an iget() and an iput() on each inode, which is very safe if we
1853  * accidentally point at an in-use or already deleted inode.  The worst that
1854  * can happen in this case is that we get a "bit already cleared" message from
1855  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1856  * e2fsck was run on this filesystem, and it must have already done the orphan
1857  * inode cleanup for us, so we can safely abort without any further action.
1858  */
1859 static void ext4_orphan_cleanup(struct super_block *sb,
1860                                 struct ext4_super_block *es)
1861 {
1862         unsigned int s_flags = sb->s_flags;
1863         int nr_orphans = 0, nr_truncates = 0;
1864 #ifdef CONFIG_QUOTA
1865         int i;
1866 #endif
1867         if (!es->s_last_orphan) {
1868                 jbd_debug(4, "no orphan inodes to clean up\n");
1869                 return;
1870         }
1871
1872         if (bdev_read_only(sb->s_bdev)) {
1873                 ext4_msg(sb, KERN_ERR, "write access "
1874                         "unavailable, skipping orphan cleanup");
1875                 return;
1876         }
1877
1878         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1879                 if (es->s_last_orphan)
1880                         jbd_debug(1, "Errors on filesystem, "
1881                                   "clearing orphan list.\n");
1882                 es->s_last_orphan = 0;
1883                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1884                 return;
1885         }
1886
1887         if (s_flags & MS_RDONLY) {
1888                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
1889                 sb->s_flags &= ~MS_RDONLY;
1890         }
1891 #ifdef CONFIG_QUOTA
1892         /* Needed for iput() to work correctly and not trash data */
1893         sb->s_flags |= MS_ACTIVE;
1894         /* Turn on quotas so that they are updated correctly */
1895         for (i = 0; i < MAXQUOTAS; i++) {
1896                 if (EXT4_SB(sb)->s_qf_names[i]) {
1897                         int ret = ext4_quota_on_mount(sb, i);
1898                         if (ret < 0)
1899                                 ext4_msg(sb, KERN_ERR,
1900                                         "Cannot turn on journaled "
1901                                         "quota: error %d", ret);
1902                 }
1903         }
1904 #endif
1905
1906         while (es->s_last_orphan) {
1907                 struct inode *inode;
1908
1909                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1910                 if (IS_ERR(inode)) {
1911                         es->s_last_orphan = 0;
1912                         break;
1913                 }
1914
1915                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1916                 vfs_dq_init(inode);
1917                 if (inode->i_nlink) {
1918                         ext4_msg(sb, KERN_DEBUG,
1919                                 "%s: truncating inode %lu to %lld bytes",
1920                                 __func__, inode->i_ino, inode->i_size);
1921                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1922                                   inode->i_ino, inode->i_size);
1923                         ext4_truncate(inode);
1924                         nr_truncates++;
1925                 } else {
1926                         ext4_msg(sb, KERN_DEBUG,
1927                                 "%s: deleting unreferenced inode %lu",
1928                                 __func__, inode->i_ino);
1929                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1930                                   inode->i_ino);
1931                         nr_orphans++;
1932                 }
1933                 iput(inode);  /* The delete magic happens here! */
1934         }
1935
1936 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1937
1938         if (nr_orphans)
1939                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
1940                        PLURAL(nr_orphans));
1941         if (nr_truncates)
1942                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
1943                        PLURAL(nr_truncates));
1944 #ifdef CONFIG_QUOTA
1945         /* Turn quotas off */
1946         for (i = 0; i < MAXQUOTAS; i++) {
1947                 if (sb_dqopt(sb)->files[i])
1948                         vfs_quota_off(sb, i, 0);
1949         }
1950 #endif
1951         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1952 }
1953
1954 /*
1955  * Maximal extent format file size.
1956  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1957  * extent format containers, within a sector_t, and within i_blocks
1958  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1959  * so that won't be a limiting factor.
1960  *
1961  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1962  */
1963 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1964 {
1965         loff_t res;
1966         loff_t upper_limit = MAX_LFS_FILESIZE;
1967
1968         /* small i_blocks in vfs inode? */
1969         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1970                 /*
1971                  * CONFIG_LBDAF is not enabled implies the inode
1972                  * i_block represent total blocks in 512 bytes
1973                  * 32 == size of vfs inode i_blocks * 8
1974                  */
1975                 upper_limit = (1LL << 32) - 1;
1976
1977                 /* total blocks in file system block size */
1978                 upper_limit >>= (blkbits - 9);
1979                 upper_limit <<= blkbits;
1980         }
1981
1982         /* 32-bit extent-start container, ee_block */
1983         res = 1LL << 32;
1984         res <<= blkbits;
1985         res -= 1;
1986
1987         /* Sanity check against vm- & vfs- imposed limits */
1988         if (res > upper_limit)
1989                 res = upper_limit;
1990
1991         return res;
1992 }
1993
1994 /*
1995  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
1996  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
1997  * We need to be 1 filesystem block less than the 2^48 sector limit.
1998  */
1999 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2000 {
2001         loff_t res = EXT4_NDIR_BLOCKS;
2002         int meta_blocks;
2003         loff_t upper_limit;
2004         /* This is calculated to be the largest file size for a dense, block
2005          * mapped file such that the file's total number of 512-byte sectors,
2006          * including data and all indirect blocks, does not exceed (2^48 - 1).
2007          *
2008          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2009          * number of 512-byte sectors of the file.
2010          */
2011
2012         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2013                 /*
2014                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2015                  * the inode i_block field represents total file blocks in
2016                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2017                  */
2018                 upper_limit = (1LL << 32) - 1;
2019
2020                 /* total blocks in file system block size */
2021                 upper_limit >>= (bits - 9);
2022
2023         } else {
2024                 /*
2025                  * We use 48 bit ext4_inode i_blocks
2026                  * With EXT4_HUGE_FILE_FL set the i_blocks
2027                  * represent total number of blocks in
2028                  * file system block size
2029                  */
2030                 upper_limit = (1LL << 48) - 1;
2031
2032         }
2033
2034         /* indirect blocks */
2035         meta_blocks = 1;
2036         /* double indirect blocks */
2037         meta_blocks += 1 + (1LL << (bits-2));
2038         /* tripple indirect blocks */
2039         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2040
2041         upper_limit -= meta_blocks;
2042         upper_limit <<= bits;
2043
2044         res += 1LL << (bits-2);
2045         res += 1LL << (2*(bits-2));
2046         res += 1LL << (3*(bits-2));
2047         res <<= bits;
2048         if (res > upper_limit)
2049                 res = upper_limit;
2050
2051         if (res > MAX_LFS_FILESIZE)
2052                 res = MAX_LFS_FILESIZE;
2053
2054         return res;
2055 }
2056
2057 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2058                                    ext4_fsblk_t logical_sb_block, int nr)
2059 {
2060         struct ext4_sb_info *sbi = EXT4_SB(sb);
2061         ext4_group_t bg, first_meta_bg;
2062         int has_super = 0;
2063
2064         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2065
2066         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2067             nr < first_meta_bg)
2068                 return logical_sb_block + nr + 1;
2069         bg = sbi->s_desc_per_block * nr;
2070         if (ext4_bg_has_super(sb, bg))
2071                 has_super = 1;
2072
2073         return (has_super + ext4_group_first_block_no(sb, bg));
2074 }
2075
2076 /**
2077  * ext4_get_stripe_size: Get the stripe size.
2078  * @sbi: In memory super block info
2079  *
2080  * If we have specified it via mount option, then
2081  * use the mount option value. If the value specified at mount time is
2082  * greater than the blocks per group use the super block value.
2083  * If the super block value is greater than blocks per group return 0.
2084  * Allocator needs it be less than blocks per group.
2085  *
2086  */
2087 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2088 {
2089         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2090         unsigned long stripe_width =
2091                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2092
2093         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2094                 return sbi->s_stripe;
2095
2096         if (stripe_width <= sbi->s_blocks_per_group)
2097                 return stripe_width;
2098
2099         if (stride <= sbi->s_blocks_per_group)
2100                 return stride;
2101
2102         return 0;
2103 }
2104
2105 /* sysfs supprt */
2106
2107 struct ext4_attr {
2108         struct attribute attr;
2109         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2110         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *, 
2111                          const char *, size_t);
2112         int offset;
2113 };
2114
2115 static int parse_strtoul(const char *buf,
2116                 unsigned long max, unsigned long *value)
2117 {
2118         char *endp;
2119
2120         while (*buf && isspace(*buf))
2121                 buf++;
2122         *value = simple_strtoul(buf, &endp, 0);
2123         while (*endp && isspace(*endp))
2124                 endp++;
2125         if (*endp || *value > max)
2126                 return -EINVAL;
2127
2128         return 0;
2129 }
2130
2131 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2132                                               struct ext4_sb_info *sbi,
2133                                               char *buf)
2134 {
2135         return snprintf(buf, PAGE_SIZE, "%llu\n",
2136                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2137 }
2138
2139 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2140                                          struct ext4_sb_info *sbi, char *buf)
2141 {
2142         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2143
2144         return snprintf(buf, PAGE_SIZE, "%lu\n",
2145                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2146                          sbi->s_sectors_written_start) >> 1);
2147 }
2148
2149 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2150                                           struct ext4_sb_info *sbi, char *buf)
2151 {
2152         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2153
2154         return snprintf(buf, PAGE_SIZE, "%llu\n",
2155                         sbi->s_kbytes_written + 
2156                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2157                           EXT4_SB(sb)->s_sectors_written_start) >> 1));
2158 }
2159
2160 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2161                                           struct ext4_sb_info *sbi,
2162                                           const char *buf, size_t count)
2163 {
2164         unsigned long t;
2165
2166         if (parse_strtoul(buf, 0x40000000, &t))
2167                 return -EINVAL;
2168
2169         if (!is_power_of_2(t))
2170                 return -EINVAL;
2171
2172         sbi->s_inode_readahead_blks = t;
2173         return count;
2174 }
2175
2176 static ssize_t sbi_ui_show(struct ext4_attr *a,
2177                            struct ext4_sb_info *sbi, char *buf)
2178 {
2179         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2180
2181         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2182 }
2183
2184 static ssize_t sbi_ui_store(struct ext4_attr *a,
2185                             struct ext4_sb_info *sbi,
2186                             const char *buf, size_t count)
2187 {
2188         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2189         unsigned long t;
2190
2191         if (parse_strtoul(buf, 0xffffffff, &t))
2192                 return -EINVAL;
2193         *ui = t;
2194         return count;
2195 }
2196
2197 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2198 static struct ext4_attr ext4_attr_##_name = {                   \
2199         .attr = {.name = __stringify(_name), .mode = _mode },   \
2200         .show   = _show,                                        \
2201         .store  = _store,                                       \
2202         .offset = offsetof(struct ext4_sb_info, _elname),       \
2203 }
2204 #define EXT4_ATTR(name, mode, show, store) \
2205 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2206
2207 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2208 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2209 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2210         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2211 #define ATTR_LIST(name) &ext4_attr_##name.attr
2212
2213 EXT4_RO_ATTR(delayed_allocation_blocks);
2214 EXT4_RO_ATTR(session_write_kbytes);
2215 EXT4_RO_ATTR(lifetime_write_kbytes);
2216 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2217                  inode_readahead_blks_store, s_inode_readahead_blks);
2218 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2219 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2220 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2221 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2222 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2223 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2224 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2225 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2226
2227 static struct attribute *ext4_attrs[] = {
2228         ATTR_LIST(delayed_allocation_blocks),
2229         ATTR_LIST(session_write_kbytes),
2230         ATTR_LIST(lifetime_write_kbytes),
2231         ATTR_LIST(inode_readahead_blks),
2232         ATTR_LIST(inode_goal),
2233         ATTR_LIST(mb_stats),
2234         ATTR_LIST(mb_max_to_scan),
2235         ATTR_LIST(mb_min_to_scan),
2236         ATTR_LIST(mb_order2_req),
2237         ATTR_LIST(mb_stream_req),
2238         ATTR_LIST(mb_group_prealloc),
2239         ATTR_LIST(max_writeback_mb_bump),
2240         NULL,
2241 };
2242
2243 static ssize_t ext4_attr_show(struct kobject *kobj,
2244                               struct attribute *attr, char *buf)
2245 {
2246         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2247                                                 s_kobj);
2248         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2249
2250         return a->show ? a->show(a, sbi, buf) : 0;
2251 }
2252
2253 static ssize_t ext4_attr_store(struct kobject *kobj,
2254                                struct attribute *attr,
2255                                const char *buf, size_t len)
2256 {
2257         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2258                                                 s_kobj);
2259         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2260
2261         return a->store ? a->store(a, sbi, buf, len) : 0;
2262 }
2263
2264 static void ext4_sb_release(struct kobject *kobj)
2265 {
2266         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2267                                                 s_kobj);
2268         complete(&sbi->s_kobj_unregister);
2269 }
2270
2271
2272 static struct sysfs_ops ext4_attr_ops = {
2273         .show   = ext4_attr_show,
2274         .store  = ext4_attr_store,
2275 };
2276
2277 static struct kobj_type ext4_ktype = {
2278         .default_attrs  = ext4_attrs,
2279         .sysfs_ops      = &ext4_attr_ops,
2280         .release        = ext4_sb_release,
2281 };
2282
2283 /*
2284  * Check whether this filesystem can be mounted based on
2285  * the features present and the RDONLY/RDWR mount requested.
2286  * Returns 1 if this filesystem can be mounted as requested,
2287  * 0 if it cannot be.
2288  */
2289 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2290 {
2291         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2292                 ext4_msg(sb, KERN_ERR,
2293                         "Couldn't mount because of "
2294                         "unsupported optional features (%x)",
2295                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2296                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2297                 return 0;
2298         }
2299
2300         if (readonly)
2301                 return 1;
2302
2303         /* Check that feature set is OK for a read-write mount */
2304         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2305                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2306                          "unsupported optional features (%x)",
2307                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2308                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2309                 return 0;
2310         }
2311         /*
2312          * Large file size enabled file system can only be mounted
2313          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2314          */
2315         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2316                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2317                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2318                                  "cannot be mounted RDWR without "
2319                                  "CONFIG_LBDAF");
2320                         return 0;
2321                 }
2322         }
2323         return 1;
2324 }
2325
2326 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2327                                 __releases(kernel_lock)
2328                                 __acquires(kernel_lock)
2329 {
2330         struct buffer_head *bh;
2331         struct ext4_super_block *es = NULL;
2332         struct ext4_sb_info *sbi;
2333         ext4_fsblk_t block;
2334         ext4_fsblk_t sb_block = get_sb_block(&data);
2335         ext4_fsblk_t logical_sb_block;
2336         unsigned long offset = 0;
2337         unsigned long journal_devnum = 0;
2338         unsigned long def_mount_opts;
2339         struct inode *root;
2340         char *cp;
2341         const char *descr;
2342         int ret = -EINVAL;
2343         int blocksize;
2344         unsigned int db_count;
2345         unsigned int i;
2346         int needs_recovery, has_huge_files;
2347         __u64 blocks_count;
2348         int err;
2349         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2350
2351         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2352         if (!sbi)
2353                 return -ENOMEM;
2354
2355         sbi->s_blockgroup_lock =
2356                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2357         if (!sbi->s_blockgroup_lock) {
2358                 kfree(sbi);
2359                 return -ENOMEM;
2360         }
2361         sb->s_fs_info = sbi;
2362         sbi->s_mount_opt = 0;
2363         sbi->s_resuid = EXT4_DEF_RESUID;
2364         sbi->s_resgid = EXT4_DEF_RESGID;
2365         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2366         sbi->s_sb_block = sb_block;
2367         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2368                                                       sectors[1]);
2369
2370         unlock_kernel();
2371
2372         /* Cleanup superblock name */
2373         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2374                 *cp = '!';
2375
2376         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2377         if (!blocksize) {
2378                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2379                 goto out_fail;
2380         }
2381
2382         /*
2383          * The ext4 superblock will not be buffer aligned for other than 1kB
2384          * block sizes.  We need to calculate the offset from buffer start.
2385          */
2386         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2387                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2388                 offset = do_div(logical_sb_block, blocksize);
2389         } else {
2390                 logical_sb_block = sb_block;
2391         }
2392
2393         if (!(bh = sb_bread(sb, logical_sb_block))) {
2394                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2395                 goto out_fail;
2396         }
2397         /*
2398          * Note: s_es must be initialized as soon as possible because
2399          *       some ext4 macro-instructions depend on its value
2400          */
2401         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2402         sbi->s_es = es;
2403         sb->s_magic = le16_to_cpu(es->s_magic);
2404         if (sb->s_magic != EXT4_SUPER_MAGIC)
2405                 goto cantfind_ext4;
2406         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2407
2408         /* Set defaults before we parse the mount options */
2409         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2410         if (def_mount_opts & EXT4_DEFM_DEBUG)
2411                 set_opt(sbi->s_mount_opt, DEBUG);
2412         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
2413                 set_opt(sbi->s_mount_opt, GRPID);
2414         if (def_mount_opts & EXT4_DEFM_UID16)
2415                 set_opt(sbi->s_mount_opt, NO_UID32);
2416 #ifdef CONFIG_EXT4_FS_XATTR
2417         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2418                 set_opt(sbi->s_mount_opt, XATTR_USER);
2419 #endif
2420 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2421         if (def_mount_opts & EXT4_DEFM_ACL)
2422                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2423 #endif
2424         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2425                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2426         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2427                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2428         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2429                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2430
2431         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2432                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2433         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2434                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2435         else
2436                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2437
2438         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2439         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2440         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2441         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2442         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2443
2444         set_opt(sbi->s_mount_opt, BARRIER);
2445
2446         /*
2447          * enable delayed allocation by default
2448          * Use -o nodelalloc to turn it off
2449          */
2450         set_opt(sbi->s_mount_opt, DELALLOC);
2451
2452         if (!parse_options((char *) data, sb, &journal_devnum,
2453                            &journal_ioprio, NULL, 0))
2454                 goto failed_mount;
2455
2456         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2457                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2458
2459         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2460             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2461              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2462              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2463                 ext4_msg(sb, KERN_WARNING,
2464                        "feature flags set on rev 0 fs, "
2465                        "running e2fsck is recommended");
2466
2467         /*
2468          * Check feature flags regardless of the revision level, since we
2469          * previously didn't change the revision level when setting the flags,
2470          * so there is a chance incompat flags are set on a rev 0 filesystem.
2471          */
2472         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
2473                 goto failed_mount;
2474
2475         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2476
2477         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2478             blocksize > EXT4_MAX_BLOCK_SIZE) {
2479                 ext4_msg(sb, KERN_ERR,
2480                        "Unsupported filesystem blocksize %d", blocksize);
2481                 goto failed_mount;
2482         }
2483
2484         if (sb->s_blocksize != blocksize) {
2485                 /* Validate the filesystem blocksize */
2486                 if (!sb_set_blocksize(sb, blocksize)) {
2487                         ext4_msg(sb, KERN_ERR, "bad block size %d",
2488                                         blocksize);
2489                         goto failed_mount;
2490                 }
2491
2492                 brelse(bh);
2493                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2494                 offset = do_div(logical_sb_block, blocksize);
2495                 bh = sb_bread(sb, logical_sb_block);
2496                 if (!bh) {
2497                         ext4_msg(sb, KERN_ERR,
2498                                "Can't read superblock on 2nd try");
2499                         goto failed_mount;
2500                 }
2501                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2502                 sbi->s_es = es;
2503                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2504                         ext4_msg(sb, KERN_ERR,
2505                                "Magic mismatch, very weird!");
2506                         goto failed_mount;
2507                 }
2508         }
2509
2510         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2511                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2512         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2513                                                       has_huge_files);
2514         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2515
2516         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2517                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2518                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2519         } else {
2520                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2521                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2522                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2523                     (!is_power_of_2(sbi->s_inode_size)) ||
2524                     (sbi->s_inode_size > blocksize)) {
2525                         ext4_msg(sb, KERN_ERR,
2526                                "unsupported inode size: %d",
2527                                sbi->s_inode_size);
2528                         goto failed_mount;
2529                 }
2530                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2531                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2532         }
2533
2534         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2535         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2536                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2537                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2538                     !is_power_of_2(sbi->s_desc_size)) {
2539                         ext4_msg(sb, KERN_ERR,
2540                                "unsupported descriptor size %lu",
2541                                sbi->s_desc_size);
2542                         goto failed_mount;
2543                 }
2544         } else
2545                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2546
2547         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2548         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2549         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2550                 goto cantfind_ext4;
2551
2552         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2553         if (sbi->s_inodes_per_block == 0)
2554                 goto cantfind_ext4;
2555         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2556                                         sbi->s_inodes_per_block;
2557         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2558         sbi->s_sbh = bh;
2559         sbi->s_mount_state = le16_to_cpu(es->s_state);
2560         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2561         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2562
2563         for (i = 0; i < 4; i++)
2564                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2565         sbi->s_def_hash_version = es->s_def_hash_version;
2566         i = le32_to_cpu(es->s_flags);
2567         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2568                 sbi->s_hash_unsigned = 3;
2569         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2570 #ifdef __CHAR_UNSIGNED__
2571                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2572                 sbi->s_hash_unsigned = 3;
2573 #else
2574                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2575 #endif
2576                 sb->s_dirt = 1;
2577         }
2578
2579         if (sbi->s_blocks_per_group > blocksize * 8) {
2580                 ext4_msg(sb, KERN_ERR,
2581                        "#blocks per group too big: %lu",
2582                        sbi->s_blocks_per_group);
2583                 goto failed_mount;
2584         }
2585         if (sbi->s_inodes_per_group > blocksize * 8) {
2586                 ext4_msg(sb, KERN_ERR,
2587                        "#inodes per group too big: %lu",
2588                        sbi->s_inodes_per_group);
2589                 goto failed_mount;
2590         }
2591
2592         /*
2593          * Test whether we have more sectors than will fit in sector_t,
2594          * and whether the max offset is addressable by the page cache.
2595          */
2596         if ((ext4_blocks_count(es) >
2597              (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
2598             (ext4_blocks_count(es) >
2599              (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
2600                 ext4_msg(sb, KERN_ERR, "filesystem"
2601                          " too large to mount safely on this system");
2602                 if (sizeof(sector_t) < 8)
2603                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
2604                 ret = -EFBIG;
2605                 goto failed_mount;
2606         }
2607
2608         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2609                 goto cantfind_ext4;
2610
2611         /* check blocks count against device size */
2612         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2613         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2614                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2615                        "exceeds size of device (%llu blocks)",
2616                        ext4_blocks_count(es), blocks_count);
2617                 goto failed_mount;
2618         }
2619
2620         /*
2621          * It makes no sense for the first data block to be beyond the end
2622          * of the filesystem.
2623          */
2624         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2625                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2626                          "block %u is beyond end of filesystem (%llu)",
2627                          le32_to_cpu(es->s_first_data_block),
2628                          ext4_blocks_count(es));
2629                 goto failed_mount;
2630         }
2631         blocks_count = (ext4_blocks_count(es) -
2632                         le32_to_cpu(es->s_first_data_block) +
2633                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2634         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2635         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2636                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2637                        "(block count %llu, first data block %u, "
2638                        "blocks per group %lu)", sbi->s_groups_count,
2639                        ext4_blocks_count(es),
2640                        le32_to_cpu(es->s_first_data_block),
2641                        EXT4_BLOCKS_PER_GROUP(sb));
2642                 goto failed_mount;
2643         }
2644         sbi->s_groups_count = blocks_count;
2645         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
2646                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
2647         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2648                    EXT4_DESC_PER_BLOCK(sb);
2649         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2650                                     GFP_KERNEL);
2651         if (sbi->s_group_desc == NULL) {
2652                 ext4_msg(sb, KERN_ERR, "not enough memory");
2653                 goto failed_mount;
2654         }
2655
2656 #ifdef CONFIG_PROC_FS
2657         if (ext4_proc_root)
2658                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2659 #endif
2660
2661         bgl_lock_init(sbi->s_blockgroup_lock);
2662
2663         for (i = 0; i < db_count; i++) {
2664                 block = descriptor_loc(sb, logical_sb_block, i);
2665                 sbi->s_group_desc[i] = sb_bread(sb, block);
2666                 if (!sbi->s_group_desc[i]) {
2667                         ext4_msg(sb, KERN_ERR,
2668                                "can't read group descriptor %d", i);
2669                         db_count = i;
2670                         goto failed_mount2;
2671                 }
2672         }
2673         if (!ext4_check_descriptors(sb)) {
2674                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2675                 goto failed_mount2;
2676         }
2677         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2678                 if (!ext4_fill_flex_info(sb)) {
2679                         ext4_msg(sb, KERN_ERR,
2680                                "unable to initialize "
2681                                "flex_bg meta info!");
2682                         goto failed_mount2;
2683                 }
2684
2685         sbi->s_gdb_count = db_count;
2686         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2687         spin_lock_init(&sbi->s_next_gen_lock);
2688
2689         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2690                         ext4_count_free_blocks(sb));
2691         if (!err) {
2692                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2693                                 ext4_count_free_inodes(sb));
2694         }
2695         if (!err) {
2696                 err = percpu_counter_init(&sbi->s_dirs_counter,
2697                                 ext4_count_dirs(sb));
2698         }
2699         if (!err) {
2700                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2701         }
2702         if (err) {
2703                 ext4_msg(sb, KERN_ERR, "insufficient memory");
2704                 goto failed_mount3;
2705         }
2706
2707         sbi->s_stripe = ext4_get_stripe_size(sbi);
2708         sbi->s_max_writeback_mb_bump = 128;
2709
2710         /*
2711          * set up enough so that it can read an inode
2712          */
2713         if (!test_opt(sb, NOLOAD) &&
2714             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2715                 sb->s_op = &ext4_sops;
2716         else
2717                 sb->s_op = &ext4_nojournal_sops;
2718         sb->s_export_op = &ext4_export_ops;
2719         sb->s_xattr = ext4_xattr_handlers;
2720 #ifdef CONFIG_QUOTA
2721         sb->s_qcop = &ext4_qctl_operations;
2722         sb->dq_op = &ext4_quota_operations;
2723 #endif
2724         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2725         mutex_init(&sbi->s_orphan_lock);
2726         mutex_init(&sbi->s_resize_lock);
2727
2728         sb->s_root = NULL;
2729
2730         needs_recovery = (es->s_last_orphan != 0 ||
2731                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2732                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2733
2734         /*
2735          * The first inode we look at is the journal inode.  Don't try
2736          * root first: it may be modified in the journal!
2737          */
2738         if (!test_opt(sb, NOLOAD) &&
2739             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2740                 if (ext4_load_journal(sb, es, journal_devnum))
2741                         goto failed_mount3;
2742                 if (!(sb->s_flags & MS_RDONLY) &&
2743                     EXT4_SB(sb)->s_journal->j_failed_commit) {
2744                         ext4_msg(sb, KERN_CRIT, "error: "
2745                                "ext4_fill_super: Journal transaction "
2746                                "%u is corrupt",
2747                                EXT4_SB(sb)->s_journal->j_failed_commit);
2748                         if (test_opt(sb, ERRORS_RO)) {
2749                                 ext4_msg(sb, KERN_CRIT,
2750                                        "Mounting filesystem read-only");
2751                                 sb->s_flags |= MS_RDONLY;
2752                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2753                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2754                         }
2755                         if (test_opt(sb, ERRORS_PANIC)) {
2756                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2757                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2758                                 ext4_commit_super(sb, 1);
2759                                 goto failed_mount4;
2760                         }
2761                 }
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            &n