]> nv-tegra.nvidia Code Review - linux-2.6.git/blob - fs/ext4/super.c
ext4: Adjust ext4_da_writepages() to write out larger contiguous chunks
[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 static int default_mb_history_length = 1000;
54
55 module_param_named(default_mb_history_length, default_mb_history_length,
56                    int, 0644);
57 MODULE_PARM_DESC(default_mb_history_length,
58                  "Default number of entries saved for mb_history");
59
60 struct proc_dir_entry *ext4_proc_root;
61 static struct kset *ext4_kset;
62
63 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
64                              unsigned long journal_devnum);
65 static int ext4_commit_super(struct super_block *sb, int sync);
66 static void ext4_mark_recovery_complete(struct super_block *sb,
67                                         struct ext4_super_block *es);
68 static void ext4_clear_journal_err(struct super_block *sb,
69                                    struct ext4_super_block *es);
70 static int ext4_sync_fs(struct super_block *sb, int wait);
71 static const char *ext4_decode_error(struct super_block *sb, int errno,
72                                      char nbuf[16]);
73 static int ext4_remount(struct super_block *sb, int *flags, char *data);
74 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
75 static int ext4_unfreeze(struct super_block *sb);
76 static void ext4_write_super(struct super_block *sb);
77 static int ext4_freeze(struct super_block *sb);
78
79
80 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
81                                struct ext4_group_desc *bg)
82 {
83         return le32_to_cpu(bg->bg_block_bitmap_lo) |
84                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
85                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
86 }
87
88 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
89                                struct ext4_group_desc *bg)
90 {
91         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
92                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
93                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
94 }
95
96 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
97                               struct ext4_group_desc *bg)
98 {
99         return le32_to_cpu(bg->bg_inode_table_lo) |
100                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
101                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
102 }
103
104 __u32 ext4_free_blks_count(struct super_block *sb,
105                               struct ext4_group_desc *bg)
106 {
107         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
108                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
109                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
110 }
111
112 __u32 ext4_free_inodes_count(struct super_block *sb,
113                               struct ext4_group_desc *bg)
114 {
115         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
116                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
117                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
118 }
119
120 __u32 ext4_used_dirs_count(struct super_block *sb,
121                               struct ext4_group_desc *bg)
122 {
123         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
124                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
125                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
126 }
127
128 __u32 ext4_itable_unused_count(struct super_block *sb,
129                               struct ext4_group_desc *bg)
130 {
131         return le16_to_cpu(bg->bg_itable_unused_lo) |
132                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
133                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
134 }
135
136 void ext4_block_bitmap_set(struct super_block *sb,
137                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
138 {
139         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
140         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
141                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
142 }
143
144 void ext4_inode_bitmap_set(struct super_block *sb,
145                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
146 {
147         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
148         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
149                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
150 }
151
152 void ext4_inode_table_set(struct super_block *sb,
153                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
154 {
155         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
156         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
157                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
158 }
159
160 void ext4_free_blks_set(struct super_block *sb,
161                           struct ext4_group_desc *bg, __u32 count)
162 {
163         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
164         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
165                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
166 }
167
168 void ext4_free_inodes_set(struct super_block *sb,
169                           struct ext4_group_desc *bg, __u32 count)
170 {
171         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
172         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
173                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
174 }
175
176 void ext4_used_dirs_set(struct super_block *sb,
177                           struct ext4_group_desc *bg, __u32 count)
178 {
179         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
180         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
181                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
182 }
183
184 void ext4_itable_unused_set(struct super_block *sb,
185                           struct ext4_group_desc *bg, __u32 count)
186 {
187         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
188         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
189                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
190 }
191
192 /*
193  * Wrappers for jbd2_journal_start/end.
194  *
195  * The only special thing we need to do here is to make sure that all
196  * journal_end calls result in the superblock being marked dirty, so
197  * that sync() will call the filesystem's write_super callback if
198  * appropriate.
199  */
200 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
201 {
202         journal_t *journal;
203
204         if (sb->s_flags & MS_RDONLY)
205                 return ERR_PTR(-EROFS);
206
207         /* Special case here: if the journal has aborted behind our
208          * backs (eg. EIO in the commit thread), then we still need to
209          * take the FS itself readonly cleanly. */
210         journal = EXT4_SB(sb)->s_journal;
211         if (journal) {
212                 if (is_journal_aborted(journal)) {
213                         ext4_abort(sb, __func__, "Detected aborted journal");
214                         return ERR_PTR(-EROFS);
215                 }
216                 return jbd2_journal_start(journal, nblocks);
217         }
218         /*
219          * We're not journaling, return the appropriate indication.
220          */
221         current->journal_info = EXT4_NOJOURNAL_HANDLE;
222         return current->journal_info;
223 }
224
225 /*
226  * The only special thing we need to do here is to make sure that all
227  * jbd2_journal_stop calls result in the superblock being marked dirty, so
228  * that sync() will call the filesystem's write_super callback if
229  * appropriate.
230  */
231 int __ext4_journal_stop(const char *where, handle_t *handle)
232 {
233         struct super_block *sb;
234         int err;
235         int rc;
236
237         if (!ext4_handle_valid(handle)) {
238                 /*
239                  * Do this here since we don't call jbd2_journal_stop() in
240                  * no-journal mode.
241                  */
242                 current->journal_info = NULL;
243                 return 0;
244         }
245         sb = handle->h_transaction->t_journal->j_private;
246         err = handle->h_err;
247         rc = jbd2_journal_stop(handle);
248
249         if (!err)
250                 err = rc;
251         if (err)
252                 __ext4_std_error(sb, where, err);
253         return err;
254 }
255
256 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
257                 struct buffer_head *bh, handle_t *handle, int err)
258 {
259         char nbuf[16];
260         const char *errstr = ext4_decode_error(NULL, err, nbuf);
261
262         BUG_ON(!ext4_handle_valid(handle));
263
264         if (bh)
265                 BUFFER_TRACE(bh, "abort");
266
267         if (!handle->h_err)
268                 handle->h_err = err;
269
270         if (is_handle_aborted(handle))
271                 return;
272
273         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
274                caller, errstr, err_fn);
275
276         jbd2_journal_abort_handle(handle);
277 }
278
279 /* Deal with the reporting of failure conditions on a filesystem such as
280  * inconsistencies detected or read IO failures.
281  *
282  * On ext2, we can store the error state of the filesystem in the
283  * superblock.  That is not possible on ext4, because we may have other
284  * write ordering constraints on the superblock which prevent us from
285  * writing it out straight away; and given that the journal is about to
286  * be aborted, we can't rely on the current, or future, transactions to
287  * write out the superblock safely.
288  *
289  * We'll just use the jbd2_journal_abort() error code to record an error in
290  * the journal instead.  On recovery, the journal will compain about
291  * that error until we've noted it down and cleared it.
292  */
293
294 static void ext4_handle_error(struct super_block *sb)
295 {
296         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
297
298         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
299         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
300
301         if (sb->s_flags & MS_RDONLY)
302                 return;
303
304         if (!test_opt(sb, ERRORS_CONT)) {
305                 journal_t *journal = EXT4_SB(sb)->s_journal;
306
307                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
308                 if (journal)
309                         jbd2_journal_abort(journal, -EIO);
310         }
311         if (test_opt(sb, ERRORS_RO)) {
312                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
313                 sb->s_flags |= MS_RDONLY;
314         }
315         ext4_commit_super(sb, 1);
316         if (test_opt(sb, ERRORS_PANIC))
317                 panic("EXT4-fs (device %s): panic forced after error\n",
318                         sb->s_id);
319 }
320
321 void ext4_error(struct super_block *sb, const char *function,
322                 const char *fmt, ...)
323 {
324         va_list args;
325
326         va_start(args, fmt);
327         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
328         vprintk(fmt, args);
329         printk("\n");
330         va_end(args);
331
332         ext4_handle_error(sb);
333 }
334
335 static const char *ext4_decode_error(struct super_block *sb, int errno,
336                                      char nbuf[16])
337 {
338         char *errstr = NULL;
339
340         switch (errno) {
341         case -EIO:
342                 errstr = "IO failure";
343                 break;
344         case -ENOMEM:
345                 errstr = "Out of memory";
346                 break;
347         case -EROFS:
348                 if (!sb || (EXT4_SB(sb)->s_journal &&
349                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
350                         errstr = "Journal has aborted";
351                 else
352                         errstr = "Readonly filesystem";
353                 break;
354         default:
355                 /* If the caller passed in an extra buffer for unknown
356                  * errors, textualise them now.  Else we just return
357                  * NULL. */
358                 if (nbuf) {
359                         /* Check for truncated error codes... */
360                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
361                                 errstr = nbuf;
362                 }
363                 break;
364         }
365
366         return errstr;
367 }
368
369 /* __ext4_std_error decodes expected errors from journaling functions
370  * automatically and invokes the appropriate error response.  */
371
372 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
373 {
374         char nbuf[16];
375         const char *errstr;
376
377         /* Special case: if the error is EROFS, and we're not already
378          * inside a transaction, then there's really no point in logging
379          * an error. */
380         if (errno == -EROFS && journal_current_handle() == NULL &&
381             (sb->s_flags & MS_RDONLY))
382                 return;
383
384         errstr = ext4_decode_error(sb, errno, nbuf);
385         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
386                sb->s_id, function, errstr);
387
388         ext4_handle_error(sb);
389 }
390
391 /*
392  * ext4_abort is a much stronger failure handler than ext4_error.  The
393  * abort function may be used to deal with unrecoverable failures such
394  * as journal IO errors or ENOMEM at a critical moment in log management.
395  *
396  * We unconditionally force the filesystem into an ABORT|READONLY state,
397  * unless the error response on the fs has been set to panic in which
398  * case we take the easy way out and panic immediately.
399  */
400
401 void ext4_abort(struct super_block *sb, const char *function,
402                 const char *fmt, ...)
403 {
404         va_list args;
405
406         va_start(args, fmt);
407         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
408         vprintk(fmt, args);
409         printk("\n");
410         va_end(args);
411
412         if (test_opt(sb, ERRORS_PANIC))
413                 panic("EXT4-fs panic from previous error\n");
414
415         if (sb->s_flags & MS_RDONLY)
416                 return;
417
418         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
419         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
420         sb->s_flags |= MS_RDONLY;
421         EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
422         if (EXT4_SB(sb)->s_journal)
423                 jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
424 }
425
426 void ext4_msg (struct super_block * sb, const char *prefix,
427                    const char *fmt, ...)
428 {
429         va_list args;
430
431         va_start(args, fmt);
432         printk("%sEXT4-fs (%s): ", prefix, sb->s_id);
433         vprintk(fmt, args);
434         printk("\n");
435         va_end(args);
436 }
437
438 void ext4_warning(struct super_block *sb, const char *function,
439                   const char *fmt, ...)
440 {
441         va_list args;
442
443         va_start(args, fmt);
444         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
445                sb->s_id, function);
446         vprintk(fmt, args);
447         printk("\n");
448         va_end(args);
449 }
450
451 void ext4_grp_locked_error(struct super_block *sb, ext4_group_t grp,
452                            const char *function, const char *fmt, ...)
453 __releases(bitlock)
454 __acquires(bitlock)
455 {
456         va_list args;
457         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
458
459         va_start(args, fmt);
460         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
461         vprintk(fmt, args);
462         printk("\n");
463         va_end(args);
464
465         if (test_opt(sb, ERRORS_CONT)) {
466                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
467                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
468                 ext4_commit_super(sb, 0);
469                 return;
470         }
471         ext4_unlock_group(sb, grp);
472         ext4_handle_error(sb);
473         /*
474          * We only get here in the ERRORS_RO case; relocking the group
475          * may be dangerous, but nothing bad will happen since the
476          * filesystem will have already been marked read/only and the
477          * journal has been aborted.  We return 1 as a hint to callers
478          * who might what to use the return value from
479          * ext4_grp_locked_error() to distinguish beween the
480          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
481          * aggressively from the ext4 function in question, with a
482          * more appropriate error code.
483          */
484         ext4_lock_group(sb, grp);
485         return;
486 }
487
488 void ext4_update_dynamic_rev(struct super_block *sb)
489 {
490         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
491
492         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
493                 return;
494
495         ext4_warning(sb, __func__,
496                      "updating to rev %d because of new feature flag, "
497                      "running e2fsck is recommended",
498                      EXT4_DYNAMIC_REV);
499
500         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
501         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
502         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
503         /* leave es->s_feature_*compat flags alone */
504         /* es->s_uuid will be set by e2fsck if empty */
505
506         /*
507          * The rest of the superblock fields should be zero, and if not it
508          * means they are likely already in use, so leave them alone.  We
509          * can leave it up to e2fsck to clean up any inconsistencies there.
510          */
511 }
512
513 /*
514  * Open the external journal device
515  */
516 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
517 {
518         struct block_device *bdev;
519         char b[BDEVNAME_SIZE];
520
521         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
522         if (IS_ERR(bdev))
523                 goto fail;
524         return bdev;
525
526 fail:
527         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
528                         __bdevname(dev, b), PTR_ERR(bdev));
529         return NULL;
530 }
531
532 /*
533  * Release the journal device
534  */
535 static int ext4_blkdev_put(struct block_device *bdev)
536 {
537         bd_release(bdev);
538         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
539 }
540
541 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
542 {
543         struct block_device *bdev;
544         int ret = -ENODEV;
545
546         bdev = sbi->journal_bdev;
547         if (bdev) {
548                 ret = ext4_blkdev_put(bdev);
549                 sbi->journal_bdev = NULL;
550         }
551         return ret;
552 }
553
554 static inline struct inode *orphan_list_entry(struct list_head *l)
555 {
556         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
557 }
558
559 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
560 {
561         struct list_head *l;
562
563         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
564                  le32_to_cpu(sbi->s_es->s_last_orphan));
565
566         printk(KERN_ERR "sb_info orphan list:\n");
567         list_for_each(l, &sbi->s_orphan) {
568                 struct inode *inode = orphan_list_entry(l);
569                 printk(KERN_ERR "  "
570                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
571                        inode->i_sb->s_id, inode->i_ino, inode,
572                        inode->i_mode, inode->i_nlink,
573                        NEXT_ORPHAN(inode));
574         }
575 }
576
577 static void ext4_put_super(struct super_block *sb)
578 {
579         struct ext4_sb_info *sbi = EXT4_SB(sb);
580         struct ext4_super_block *es = sbi->s_es;
581         int i, err;
582
583         lock_super(sb);
584         lock_kernel();
585         if (sb->s_dirt)
586                 ext4_commit_super(sb, 1);
587
588         ext4_release_system_zone(sb);
589         ext4_mb_release(sb);
590         ext4_ext_release(sb);
591         ext4_xattr_put_super(sb);
592         if (sbi->s_journal) {
593                 err = jbd2_journal_destroy(sbi->s_journal);
594                 sbi->s_journal = NULL;
595                 if (err < 0)
596                         ext4_abort(sb, __func__,
597                                    "Couldn't clean up the journal");
598         }
599         if (!(sb->s_flags & MS_RDONLY)) {
600                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
601                 es->s_state = cpu_to_le16(sbi->s_mount_state);
602                 ext4_commit_super(sb, 1);
603         }
604         if (sbi->s_proc) {
605                 remove_proc_entry(sb->s_id, ext4_proc_root);
606         }
607         kobject_del(&sbi->s_kobj);
608
609         for (i = 0; i < sbi->s_gdb_count; i++)
610                 brelse(sbi->s_group_desc[i]);
611         kfree(sbi->s_group_desc);
612         if (is_vmalloc_addr(sbi->s_flex_groups))
613                 vfree(sbi->s_flex_groups);
614         else
615                 kfree(sbi->s_flex_groups);
616         percpu_counter_destroy(&sbi->s_freeblocks_counter);
617         percpu_counter_destroy(&sbi->s_freeinodes_counter);
618         percpu_counter_destroy(&sbi->s_dirs_counter);
619         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
620         brelse(sbi->s_sbh);
621 #ifdef CONFIG_QUOTA
622         for (i = 0; i < MAXQUOTAS; i++)
623                 kfree(sbi->s_qf_names[i]);
624 #endif
625
626         /* Debugging code just in case the in-memory inode orphan list
627          * isn't empty.  The on-disk one can be non-empty if we've
628          * detected an error and taken the fs readonly, but the
629          * in-memory list had better be clean by this point. */
630         if (!list_empty(&sbi->s_orphan))
631                 dump_orphan_list(sb, sbi);
632         J_ASSERT(list_empty(&sbi->s_orphan));
633
634         invalidate_bdev(sb->s_bdev);
635         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
636                 /*
637                  * Invalidate the journal device's buffers.  We don't want them
638                  * floating about in memory - the physical journal device may
639                  * hotswapped, and it breaks the `ro-after' testing code.
640                  */
641                 sync_blockdev(sbi->journal_bdev);
642                 invalidate_bdev(sbi->journal_bdev);
643                 ext4_blkdev_remove(sbi);
644         }
645         sb->s_fs_info = NULL;
646         /*
647          * Now that we are completely done shutting down the
648          * superblock, we need to actually destroy the kobject.
649          */
650         unlock_kernel();
651         unlock_super(sb);
652         kobject_put(&sbi->s_kobj);
653         wait_for_completion(&sbi->s_kobj_unregister);
654         kfree(sbi->s_blockgroup_lock);
655         kfree(sbi);
656 }
657
658 static struct kmem_cache *ext4_inode_cachep;
659
660 /*
661  * Called inside transaction, so use GFP_NOFS
662  */
663 static struct inode *ext4_alloc_inode(struct super_block *sb)
664 {
665         struct ext4_inode_info *ei;
666
667         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
668         if (!ei)
669                 return NULL;
670
671         ei->vfs_inode.i_version = 1;
672         ei->vfs_inode.i_data.writeback_index = 0;
673         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
674         INIT_LIST_HEAD(&ei->i_prealloc_list);
675         spin_lock_init(&ei->i_prealloc_lock);
676         /*
677          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
678          * therefore it can be null here.  Don't check it, just initialize
679          * jinode.
680          */
681         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
682         ei->i_reserved_data_blocks = 0;
683         ei->i_reserved_meta_blocks = 0;
684         ei->i_allocated_meta_blocks = 0;
685         ei->i_delalloc_reserved_flag = 0;
686         spin_lock_init(&(ei->i_block_reservation_lock));
687
688         return &ei->vfs_inode;
689 }
690
691 static void ext4_destroy_inode(struct inode *inode)
692 {
693         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
694                 ext4_msg(inode->i_sb, KERN_ERR,
695                          "Inode %lu (%p): orphan list check failed!",
696                          inode->i_ino, EXT4_I(inode));
697                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
698                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
699                                 true);
700                 dump_stack();
701         }
702         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
703 }
704
705 static void init_once(void *foo)
706 {
707         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
708
709         INIT_LIST_HEAD(&ei->i_orphan);
710 #ifdef CONFIG_EXT4_FS_XATTR
711         init_rwsem(&ei->xattr_sem);
712 #endif
713         init_rwsem(&ei->i_data_sem);
714         inode_init_once(&ei->vfs_inode);
715 }
716
717 static int init_inodecache(void)
718 {
719         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
720                                              sizeof(struct ext4_inode_info),
721                                              0, (SLAB_RECLAIM_ACCOUNT|
722                                                 SLAB_MEM_SPREAD),
723                                              init_once);
724         if (ext4_inode_cachep == NULL)
725                 return -ENOMEM;
726         return 0;
727 }
728
729 static void destroy_inodecache(void)
730 {
731         kmem_cache_destroy(ext4_inode_cachep);
732 }
733
734 static void ext4_clear_inode(struct inode *inode)
735 {
736         ext4_discard_preallocations(inode);
737         if (EXT4_JOURNAL(inode))
738                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
739                                        &EXT4_I(inode)->jinode);
740 }
741
742 static inline void ext4_show_quota_options(struct seq_file *seq,
743                                            struct super_block *sb)
744 {
745 #if defined(CONFIG_QUOTA)
746         struct ext4_sb_info *sbi = EXT4_SB(sb);
747
748         if (sbi->s_jquota_fmt)
749                 seq_printf(seq, ",jqfmt=%s",
750                 (sbi->s_jquota_fmt == QFMT_VFS_OLD) ? "vfsold" : "vfsv0");
751
752         if (sbi->s_qf_names[USRQUOTA])
753                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
754
755         if (sbi->s_qf_names[GRPQUOTA])
756                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
757
758         if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
759                 seq_puts(seq, ",usrquota");
760
761         if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
762                 seq_puts(seq, ",grpquota");
763 #endif
764 }
765
766 /*
767  * Show an option if
768  *  - it's set to a non-default value OR
769  *  - if the per-sb default is different from the global default
770  */
771 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
772 {
773         int def_errors;
774         unsigned long def_mount_opts;
775         struct super_block *sb = vfs->mnt_sb;
776         struct ext4_sb_info *sbi = EXT4_SB(sb);
777         struct ext4_super_block *es = sbi->s_es;
778
779         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
780         def_errors     = le16_to_cpu(es->s_errors);
781
782         if (sbi->s_sb_block != 1)
783                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
784         if (test_opt(sb, MINIX_DF))
785                 seq_puts(seq, ",minixdf");
786         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
787                 seq_puts(seq, ",grpid");
788         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
789                 seq_puts(seq, ",nogrpid");
790         if (sbi->s_resuid != EXT4_DEF_RESUID ||
791             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
792                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
793         }
794         if (sbi->s_resgid != EXT4_DEF_RESGID ||
795             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
796                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
797         }
798         if (test_opt(sb, ERRORS_RO)) {
799                 if (def_errors == EXT4_ERRORS_PANIC ||
800                     def_errors == EXT4_ERRORS_CONTINUE) {
801                         seq_puts(seq, ",errors=remount-ro");
802                 }
803         }
804         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
805                 seq_puts(seq, ",errors=continue");
806         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
807                 seq_puts(seq, ",errors=panic");
808         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
809                 seq_puts(seq, ",nouid32");
810         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
811                 seq_puts(seq, ",debug");
812         if (test_opt(sb, OLDALLOC))
813                 seq_puts(seq, ",oldalloc");
814 #ifdef CONFIG_EXT4_FS_XATTR
815         if (test_opt(sb, XATTR_USER) &&
816                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
817                 seq_puts(seq, ",user_xattr");
818         if (!test_opt(sb, XATTR_USER) &&
819             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
820                 seq_puts(seq, ",nouser_xattr");
821         }
822 #endif
823 #ifdef CONFIG_EXT4_FS_POSIX_ACL
824         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
825                 seq_puts(seq, ",acl");
826         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
827                 seq_puts(seq, ",noacl");
828 #endif
829         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
830                 seq_printf(seq, ",commit=%u",
831                            (unsigned) (sbi->s_commit_interval / HZ));
832         }
833         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
834                 seq_printf(seq, ",min_batch_time=%u",
835                            (unsigned) sbi->s_min_batch_time);
836         }
837         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
838                 seq_printf(seq, ",max_batch_time=%u",
839                            (unsigned) sbi->s_min_batch_time);
840         }
841
842         /*
843          * We're changing the default of barrier mount option, so
844          * let's always display its mount state so it's clear what its
845          * status is.
846          */
847         seq_puts(seq, ",barrier=");
848         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
849         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
850                 seq_puts(seq, ",journal_async_commit");
851         if (test_opt(sb, NOBH))
852                 seq_puts(seq, ",nobh");
853         if (test_opt(sb, I_VERSION))
854                 seq_puts(seq, ",i_version");
855         if (!test_opt(sb, DELALLOC))
856                 seq_puts(seq, ",nodelalloc");
857
858
859         if (sbi->s_stripe)
860                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
861         /*
862          * journal mode get enabled in different ways
863          * So just print the value even if we didn't specify it
864          */
865         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
866                 seq_puts(seq, ",data=journal");
867         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
868                 seq_puts(seq, ",data=ordered");
869         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
870                 seq_puts(seq, ",data=writeback");
871
872         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
873                 seq_printf(seq, ",inode_readahead_blks=%u",
874                            sbi->s_inode_readahead_blks);
875
876         if (test_opt(sb, DATA_ERR_ABORT))
877                 seq_puts(seq, ",data_err=abort");
878
879         if (test_opt(sb, NO_AUTO_DA_ALLOC))
880                 seq_puts(seq, ",noauto_da_alloc");
881
882         ext4_show_quota_options(seq, sb);
883
884         return 0;
885 }
886
887 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
888                                         u64 ino, u32 generation)
889 {
890         struct inode *inode;
891
892         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
893                 return ERR_PTR(-ESTALE);
894         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
895                 return ERR_PTR(-ESTALE);
896
897         /* iget isn't really right if the inode is currently unallocated!!
898          *
899          * ext4_read_inode will return a bad_inode if the inode had been
900          * deleted, so we should be safe.
901          *
902          * Currently we don't know the generation for parent directory, so
903          * a generation of 0 means "accept any"
904          */
905         inode = ext4_iget(sb, ino);
906         if (IS_ERR(inode))
907                 return ERR_CAST(inode);
908         if (generation && inode->i_generation != generation) {
909                 iput(inode);
910                 return ERR_PTR(-ESTALE);
911         }
912
913         return inode;
914 }
915
916 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
917                                         int fh_len, int fh_type)
918 {
919         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
920                                     ext4_nfs_get_inode);
921 }
922
923 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
924                                         int fh_len, int fh_type)
925 {
926         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
927                                     ext4_nfs_get_inode);
928 }
929
930 /*
931  * Try to release metadata pages (indirect blocks, directories) which are
932  * mapped via the block device.  Since these pages could have journal heads
933  * which would prevent try_to_free_buffers() from freeing them, we must use
934  * jbd2 layer's try_to_free_buffers() function to release them.
935  */
936 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
937                                  gfp_t wait)
938 {
939         journal_t *journal = EXT4_SB(sb)->s_journal;
940
941         WARN_ON(PageChecked(page));
942         if (!page_has_buffers(page))
943                 return 0;
944         if (journal)
945                 return jbd2_journal_try_to_free_buffers(journal, page,
946                                                         wait & ~__GFP_WAIT);
947         return try_to_free_buffers(page);
948 }
949
950 #ifdef CONFIG_QUOTA
951 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
952 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
953
954 static int ext4_write_dquot(struct dquot *dquot);
955 static int ext4_acquire_dquot(struct dquot *dquot);
956 static int ext4_release_dquot(struct dquot *dquot);
957 static int ext4_mark_dquot_dirty(struct dquot *dquot);
958 static int ext4_write_info(struct super_block *sb, int type);
959 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
960                                 char *path, int remount);
961 static int ext4_quota_on_mount(struct super_block *sb, int type);
962 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
963                                size_t len, loff_t off);
964 static ssize_t ext4_quota_write(struct super_block *sb, int type,
965                                 const char *data, size_t len, loff_t off);
966
967 static const struct dquot_operations ext4_quota_operations = {
968         .initialize     = dquot_initialize,
969         .drop           = dquot_drop,
970         .alloc_space    = dquot_alloc_space,
971         .reserve_space  = dquot_reserve_space,
972         .claim_space    = dquot_claim_space,
973         .release_rsv    = dquot_release_reserved_space,
974         .get_reserved_space = ext4_get_reserved_space,
975         .alloc_inode    = dquot_alloc_inode,
976         .free_space     = dquot_free_space,
977         .free_inode     = dquot_free_inode,
978         .transfer       = dquot_transfer,
979         .write_dquot    = ext4_write_dquot,
980         .acquire_dquot  = ext4_acquire_dquot,
981         .release_dquot  = ext4_release_dquot,
982         .mark_dirty     = ext4_mark_dquot_dirty,
983         .write_info     = ext4_write_info,
984         .alloc_dquot    = dquot_alloc,
985         .destroy_dquot  = dquot_destroy,
986 };
987
988 static const struct quotactl_ops ext4_qctl_operations = {
989         .quota_on       = ext4_quota_on,
990         .quota_off      = vfs_quota_off,
991         .quota_sync     = vfs_quota_sync,
992         .get_info       = vfs_get_dqinfo,
993         .set_info       = vfs_set_dqinfo,
994         .get_dqblk      = vfs_get_dqblk,
995         .set_dqblk      = vfs_set_dqblk
996 };
997 #endif
998
999 static const struct super_operations ext4_sops = {
1000         .alloc_inode    = ext4_alloc_inode,
1001         .destroy_inode  = ext4_destroy_inode,
1002         .write_inode    = ext4_write_inode,
1003         .dirty_inode    = ext4_dirty_inode,
1004         .delete_inode   = ext4_delete_inode,
1005         .put_super      = ext4_put_super,
1006         .sync_fs        = ext4_sync_fs,
1007         .freeze_fs      = ext4_freeze,
1008         .unfreeze_fs    = ext4_unfreeze,
1009         .statfs         = ext4_statfs,
1010         .remount_fs     = ext4_remount,
1011         .clear_inode    = ext4_clear_inode,
1012         .show_options   = ext4_show_options,
1013 #ifdef CONFIG_QUOTA
1014         .quota_read     = ext4_quota_read,
1015         .quota_write    = ext4_quota_write,
1016 #endif
1017         .bdev_try_to_free_page = bdev_try_to_free_page,
1018 };
1019
1020 static const struct super_operations ext4_nojournal_sops = {
1021         .alloc_inode    = ext4_alloc_inode,
1022         .destroy_inode  = ext4_destroy_inode,
1023         .write_inode    = ext4_write_inode,
1024         .dirty_inode    = ext4_dirty_inode,
1025         .delete_inode   = ext4_delete_inode,
1026         .write_super    = ext4_write_super,
1027         .put_super      = ext4_put_super,
1028         .statfs         = ext4_statfs,
1029         .remount_fs     = ext4_remount,
1030         .clear_inode    = ext4_clear_inode,
1031         .show_options   = ext4_show_options,
1032 #ifdef CONFIG_QUOTA
1033         .quota_read     = ext4_quota_read,
1034         .quota_write    = ext4_quota_write,
1035 #endif
1036         .bdev_try_to_free_page = bdev_try_to_free_page,
1037 };
1038
1039 static const struct export_operations ext4_export_ops = {
1040         .fh_to_dentry = ext4_fh_to_dentry,
1041         .fh_to_parent = ext4_fh_to_parent,
1042         .get_parent = ext4_get_parent,
1043 };
1044
1045 enum {
1046         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1047         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1048         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1049         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1050         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1051         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1052         Opt_journal_update, Opt_journal_dev,
1053         Opt_journal_checksum, Opt_journal_async_commit,
1054         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1055         Opt_data_err_abort, Opt_data_err_ignore, Opt_mb_history_length,
1056         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1057         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_quota, Opt_noquota,
1058         Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err, Opt_resize,
1059         Opt_usrquota, Opt_grpquota, Opt_i_version,
1060         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1061         Opt_block_validity, Opt_noblock_validity,
1062         Opt_inode_readahead_blks, Opt_journal_ioprio
1063 };
1064
1065 static const match_table_t tokens = {
1066         {Opt_bsd_df, "bsddf"},
1067         {Opt_minix_df, "minixdf"},
1068         {Opt_grpid, "grpid"},
1069         {Opt_grpid, "bsdgroups"},
1070         {Opt_nogrpid, "nogrpid"},
1071         {Opt_nogrpid, "sysvgroups"},
1072         {Opt_resgid, "resgid=%u"},
1073         {Opt_resuid, "resuid=%u"},
1074         {Opt_sb, "sb=%u"},
1075         {Opt_err_cont, "errors=continue"},
1076         {Opt_err_panic, "errors=panic"},
1077         {Opt_err_ro, "errors=remount-ro"},
1078         {Opt_nouid32, "nouid32"},
1079         {Opt_debug, "debug"},
1080         {Opt_oldalloc, "oldalloc"},
1081         {Opt_orlov, "orlov"},
1082         {Opt_user_xattr, "user_xattr"},
1083         {Opt_nouser_xattr, "nouser_xattr"},
1084         {Opt_acl, "acl"},
1085         {Opt_noacl, "noacl"},
1086         {Opt_noload, "noload"},
1087         {Opt_nobh, "nobh"},
1088         {Opt_bh, "bh"},
1089         {Opt_commit, "commit=%u"},
1090         {Opt_min_batch_time, "min_batch_time=%u"},
1091         {Opt_max_batch_time, "max_batch_time=%u"},
1092         {Opt_journal_update, "journal=update"},
1093         {Opt_journal_dev, "journal_dev=%u"},
1094         {Opt_journal_checksum, "journal_checksum"},
1095         {Opt_journal_async_commit, "journal_async_commit"},
1096         {Opt_abort, "abort"},
1097         {Opt_data_journal, "data=journal"},
1098         {Opt_data_ordered, "data=ordered"},
1099         {Opt_data_writeback, "data=writeback"},
1100         {Opt_data_err_abort, "data_err=abort"},
1101         {Opt_data_err_ignore, "data_err=ignore"},
1102         {Opt_mb_history_length, "mb_history_length=%u"},
1103         {Opt_offusrjquota, "usrjquota="},
1104         {Opt_usrjquota, "usrjquota=%s"},
1105         {Opt_offgrpjquota, "grpjquota="},
1106         {Opt_grpjquota, "grpjquota=%s"},
1107         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1108         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1109         {Opt_grpquota, "grpquota"},
1110         {Opt_noquota, "noquota"},
1111         {Opt_quota, "quota"},
1112         {Opt_usrquota, "usrquota"},
1113         {Opt_barrier, "barrier=%u"},
1114         {Opt_barrier, "barrier"},
1115         {Opt_nobarrier, "nobarrier"},
1116         {Opt_i_version, "i_version"},
1117         {Opt_stripe, "stripe=%u"},
1118         {Opt_resize, "resize"},
1119         {Opt_delalloc, "delalloc"},
1120         {Opt_nodelalloc, "nodelalloc"},
1121         {Opt_block_validity, "block_validity"},
1122         {Opt_noblock_validity, "noblock_validity"},
1123         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1124         {Opt_journal_ioprio, "journal_ioprio=%u"},
1125         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1126         {Opt_auto_da_alloc, "auto_da_alloc"},
1127         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1128         {Opt_err, NULL},
1129 };
1130
1131 static ext4_fsblk_t get_sb_block(void **data)
1132 {
1133         ext4_fsblk_t    sb_block;
1134         char            *options = (char *) *data;
1135
1136         if (!options || strncmp(options, "sb=", 3) != 0)
1137                 return 1;       /* Default location */
1138
1139         options += 3;
1140         /* TODO: use simple_strtoll with >32bit ext4 */
1141         sb_block = simple_strtoul(options, &options, 0);
1142         if (*options && *options != ',') {
1143                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1144                        (char *) *data);
1145                 return 1;
1146         }
1147         if (*options == ',')
1148                 options++;
1149         *data = (void *) options;
1150
1151         return sb_block;
1152 }
1153
1154 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1155
1156 static int parse_options(char *options, struct super_block *sb,
1157                          unsigned long *journal_devnum,
1158                          unsigned int *journal_ioprio,
1159                          ext4_fsblk_t *n_blocks_count, int is_remount)
1160 {
1161         struct ext4_sb_info *sbi = EXT4_SB(sb);
1162         char *p;
1163         substring_t args[MAX_OPT_ARGS];
1164         int data_opt = 0;
1165         int option;
1166 #ifdef CONFIG_QUOTA
1167         int qtype, qfmt;
1168         char *qname;
1169 #endif
1170
1171         if (!options)
1172                 return 1;
1173
1174         while ((p = strsep(&options, ",")) != NULL) {
1175                 int token;
1176                 if (!*p)
1177                         continue;
1178
1179                 token = match_token(p, tokens, args);
1180                 switch (token) {
1181                 case Opt_bsd_df:
1182                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1183                         break;
1184                 case Opt_minix_df:
1185                         set_opt(sbi->s_mount_opt, MINIX_DF);
1186                         break;
1187                 case Opt_grpid:
1188                         set_opt(sbi->s_mount_opt, GRPID);
1189                         break;
1190                 case Opt_nogrpid:
1191                         clear_opt(sbi->s_mount_opt, GRPID);
1192                         break;
1193                 case Opt_resuid:
1194                         if (match_int(&args[0], &option))
1195                                 return 0;
1196                         sbi->s_resuid = option;
1197                         break;
1198                 case Opt_resgid:
1199                         if (match_int(&args[0], &option))
1200                                 return 0;
1201                         sbi->s_resgid = option;
1202                         break;
1203                 case Opt_sb:
1204                         /* handled by get_sb_block() instead of here */
1205                         /* *sb_block = match_int(&args[0]); */
1206                         break;
1207                 case Opt_err_panic:
1208                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1209                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1210                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1211                         break;
1212                 case Opt_err_ro:
1213                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1214                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1215                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1216                         break;
1217                 case Opt_err_cont:
1218                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1219                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1220                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1221                         break;
1222                 case Opt_nouid32:
1223                         set_opt(sbi->s_mount_opt, NO_UID32);
1224                         break;
1225                 case Opt_debug:
1226                         set_opt(sbi->s_mount_opt, DEBUG);
1227                         break;
1228                 case Opt_oldalloc:
1229                         set_opt(sbi->s_mount_opt, OLDALLOC);
1230                         break;
1231                 case Opt_orlov:
1232                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1233                         break;
1234 #ifdef CONFIG_EXT4_FS_XATTR
1235                 case Opt_user_xattr:
1236                         set_opt(sbi->s_mount_opt, XATTR_USER);
1237                         break;
1238                 case Opt_nouser_xattr:
1239                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1240                         break;
1241 #else
1242                 case Opt_user_xattr:
1243                 case Opt_nouser_xattr:
1244                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1245                         break;
1246 #endif
1247 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1248                 case Opt_acl:
1249                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1250                         break;
1251                 case Opt_noacl:
1252                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1253                         break;
1254 #else
1255                 case Opt_acl:
1256                 case Opt_noacl:
1257                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1258                         break;
1259 #endif
1260                 case Opt_journal_update:
1261                         /* @@@ FIXME */
1262                         /* Eventually we will want to be able to create
1263                            a journal file here.  For now, only allow the
1264                            user to specify an existing inode to be the
1265                            journal file. */
1266                         if (is_remount) {
1267                                 ext4_msg(sb, KERN_ERR,
1268                                          "Cannot specify journal on remount");
1269                                 return 0;
1270                         }
1271                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1272                         break;
1273                 case Opt_journal_dev:
1274                         if (is_remount) {
1275                                 ext4_msg(sb, KERN_ERR,
1276                                         "Cannot specify journal on remount");
1277                                 return 0;
1278                         }
1279                         if (match_int(&args[0], &option))
1280                                 return 0;
1281                         *journal_devnum = option;
1282                         break;
1283                 case Opt_journal_checksum:
1284                         break;  /* Kept for backwards compatibility */
1285                 case Opt_journal_async_commit:
1286                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1287                         break;
1288                 case Opt_noload:
1289                         set_opt(sbi->s_mount_opt, NOLOAD);
1290                         break;
1291                 case Opt_commit:
1292                         if (match_int(&args[0], &option))
1293                                 return 0;
1294                         if (option < 0)
1295                                 return 0;
1296                         if (option == 0)
1297                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1298                         sbi->s_commit_interval = HZ * option;
1299                         break;
1300                 case Opt_max_batch_time:
1301                         if (match_int(&args[0], &option))
1302                                 return 0;
1303                         if (option < 0)
1304                                 return 0;
1305                         if (option == 0)
1306                                 option = EXT4_DEF_MAX_BATCH_TIME;
1307                         sbi->s_max_batch_time = option;
1308                         break;
1309                 case Opt_min_batch_time:
1310                         if (match_int(&args[0], &option))
1311                                 return 0;
1312                         if (option < 0)
1313                                 return 0;
1314                         sbi->s_min_batch_time = option;
1315                         break;
1316                 case Opt_data_journal:
1317                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1318                         goto datacheck;
1319                 case Opt_data_ordered:
1320                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1321                         goto datacheck;
1322                 case Opt_data_writeback:
1323                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1324                 datacheck:
1325                         if (is_remount) {
1326                                 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1327                                                 != data_opt) {
1328                                         ext4_msg(sb, KERN_ERR,
1329                                                 "Cannot change data mode on remount");
1330                                         return 0;
1331                                 }
1332                         } else {
1333                                 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1334                                 sbi->s_mount_opt |= data_opt;
1335                         }
1336                         break;
1337                 case Opt_data_err_abort:
1338                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1339                         break;
1340                 case Opt_data_err_ignore:
1341                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1342                         break;
1343                 case Opt_mb_history_length:
1344                         if (match_int(&args[0], &option))
1345                                 return 0;
1346                         if (option < 0)
1347                                 return 0;
1348                         sbi->s_mb_history_max = option;
1349                         break;
1350 #ifdef CONFIG_QUOTA
1351                 case Opt_usrjquota:
1352                         qtype = USRQUOTA;
1353                         goto set_qf_name;
1354                 case Opt_grpjquota:
1355                         qtype = GRPQUOTA;
1356 set_qf_name:
1357                         if (sb_any_quota_loaded(sb) &&
1358                             !sbi->s_qf_names[qtype]) {
1359                                 ext4_msg(sb, KERN_ERR,
1360                                        "Cannot change journaled "
1361                                        "quota options when quota turned on");
1362                                 return 0;
1363                         }
1364                         qname = match_strdup(&args[0]);
1365                         if (!qname) {
1366                                 ext4_msg(sb, KERN_ERR,
1367                                         "Not enough memory for "
1368                                         "storing quotafile name");
1369                                 return 0;
1370                         }
1371                         if (sbi->s_qf_names[qtype] &&
1372                             strcmp(sbi->s_qf_names[qtype], qname)) {
1373                                 ext4_msg(sb, KERN_ERR,
1374                                         "%s quota file already "
1375                                         "specified", QTYPE2NAME(qtype));
1376                                 kfree(qname);
1377                                 return 0;
1378                         }
1379                         sbi->s_qf_names[qtype] = qname;
1380                         if (strchr(sbi->s_qf_names[qtype], '/')) {
1381                                 ext4_msg(sb, KERN_ERR,
1382                                         "quotafile must be on "
1383                                         "filesystem root");
1384                                 kfree(sbi->s_qf_names[qtype]);
1385                                 sbi->s_qf_names[qtype] = NULL;
1386                                 return 0;
1387                         }
1388                         set_opt(sbi->s_mount_opt, QUOTA);
1389                         break;
1390                 case Opt_offusrjquota:
1391                         qtype = USRQUOTA;
1392                         goto clear_qf_name;
1393                 case Opt_offgrpjquota:
1394                         qtype = GRPQUOTA;
1395 clear_qf_name:
1396                         if (sb_any_quota_loaded(sb) &&
1397                             sbi->s_qf_names[qtype]) {
1398                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1399                                         "journaled quota options when "
1400                                         "quota turned on");
1401                                 return 0;
1402                         }
1403                         /*
1404                          * The space will be released later when all options
1405                          * are confirmed to be correct
1406                          */
1407                         sbi->s_qf_names[qtype] = NULL;
1408                         break;
1409                 case Opt_jqfmt_vfsold:
1410                         qfmt = QFMT_VFS_OLD;
1411                         goto set_qf_format;
1412                 case Opt_jqfmt_vfsv0:
1413                         qfmt = QFMT_VFS_V0;
1414 set_qf_format:
1415                         if (sb_any_quota_loaded(sb) &&
1416                             sbi->s_jquota_fmt != qfmt) {
1417                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1418                                         "journaled quota options when "
1419                                         "quota turned on");
1420                                 return 0;
1421                         }
1422                         sbi->s_jquota_fmt = qfmt;
1423                         break;
1424                 case Opt_quota:
1425                 case Opt_usrquota:
1426                         set_opt(sbi->s_mount_opt, QUOTA);
1427                         set_opt(sbi->s_mount_opt, USRQUOTA);
1428                         break;
1429                 case Opt_grpquota:
1430                         set_opt(sbi->s_mount_opt, QUOTA);
1431                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1432                         break;
1433                 case Opt_noquota:
1434                         if (sb_any_quota_loaded(sb)) {
1435                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1436                                         "options when quota turned on");
1437                                 return 0;
1438                         }
1439                         clear_opt(sbi->s_mount_opt, QUOTA);
1440                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1441                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1442                         break;
1443 #else
1444                 case Opt_quota:
1445                 case Opt_usrquota:
1446                 case Opt_grpquota:
1447                         ext4_msg(sb, KERN_ERR,
1448                                 "quota options not supported");
1449                         break;
1450                 case Opt_usrjquota:
1451                 case Opt_grpjquota:
1452                 case Opt_offusrjquota:
1453                 case Opt_offgrpjquota:
1454                 case Opt_jqfmt_vfsold:
1455                 case Opt_jqfmt_vfsv0:
1456                         ext4_msg(sb, KERN_ERR,
1457                                 "journaled quota options not supported");
1458                         break;
1459                 case Opt_noquota:
1460                         break;
1461 #endif
1462                 case Opt_abort:
1463                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1464                         break;
1465                 case Opt_nobarrier:
1466                         clear_opt(sbi->s_mount_opt, BARRIER);
1467                         break;
1468                 case Opt_barrier:
1469                         if (match_int(&args[0], &option)) {
1470                                 set_opt(sbi->s_mount_opt, BARRIER);
1471                                 break;
1472                         }
1473                         if (option)
1474                                 set_opt(sbi->s_mount_opt, BARRIER);
1475                         else
1476                                 clear_opt(sbi->s_mount_opt, BARRIER);
1477                         break;
1478                 case Opt_ignore:
1479                         break;
1480                 case Opt_resize:
1481                         if (!is_remount) {
1482                                 ext4_msg(sb, KERN_ERR,
1483                                         "resize option only available "
1484                                         "for remount");
1485                                 return 0;
1486                         }
1487                         if (match_int(&args[0], &option) != 0)
1488                                 return 0;
1489                         *n_blocks_count = option;
1490                         break;
1491                 case Opt_nobh:
1492                         set_opt(sbi->s_mount_opt, NOBH);
1493                         break;
1494                 case Opt_bh:
1495                         clear_opt(sbi->s_mount_opt, NOBH);
1496                         break;
1497                 case Opt_i_version:
1498                         set_opt(sbi->s_mount_opt, I_VERSION);
1499                         sb->s_flags |= MS_I_VERSION;
1500                         break;
1501                 case Opt_nodelalloc:
1502                         clear_opt(sbi->s_mount_opt, DELALLOC);
1503                         break;
1504                 case Opt_stripe:
1505                         if (match_int(&args[0], &option))
1506                                 return 0;
1507                         if (option < 0)
1508                                 return 0;
1509                         sbi->s_stripe = option;
1510                         break;
1511                 case Opt_delalloc:
1512                         set_opt(sbi->s_mount_opt, DELALLOC);
1513                         break;
1514                 case Opt_block_validity:
1515                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1516                         break;
1517                 case Opt_noblock_validity:
1518                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1519                         break;
1520                 case Opt_inode_readahead_blks:
1521                         if (match_int(&args[0], &option))
1522                                 return 0;
1523                         if (option < 0 || option > (1 << 30))
1524                                 return 0;
1525                         if (!is_power_of_2(option)) {
1526                                 ext4_msg(sb, KERN_ERR,
1527                                          "EXT4-fs: inode_readahead_blks"
1528                                          " must be a power of 2");
1529                                 return 0;
1530                         }
1531                         sbi->s_inode_readahead_blks = option;
1532                         break;
1533                 case Opt_journal_ioprio:
1534                         if (match_int(&args[0], &option))
1535                                 return 0;
1536                         if (option < 0 || option > 7)
1537                                 break;
1538                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1539                                                             option);
1540                         break;
1541                 case Opt_noauto_da_alloc:
1542                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1543                         break;
1544                 case Opt_auto_da_alloc:
1545                         if (match_int(&args[0], &option)) {
1546                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1547                                 break;
1548                         }
1549                         if (option)
1550                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1551                         else
1552                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1553                         break;
1554                 default:
1555                         ext4_msg(sb, KERN_ERR,
1556                                "Unrecognized mount option \"%s\" "
1557                                "or missing value", p);
1558                         return 0;
1559                 }
1560         }
1561 #ifdef CONFIG_QUOTA
1562         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1563                 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1564                      sbi->s_qf_names[USRQUOTA])
1565                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1566
1567                 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1568                      sbi->s_qf_names[GRPQUOTA])
1569                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1570
1571                 if ((sbi->s_qf_names[USRQUOTA] &&
1572                                 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1573                     (sbi->s_qf_names[GRPQUOTA] &&
1574                                 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1575                         ext4_msg(sb, KERN_ERR, "old and new quota "
1576                                         "format mixing");
1577                         return 0;
1578                 }
1579
1580                 if (!sbi->s_jquota_fmt) {
1581                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1582                                         "not specified");
1583                         return 0;
1584                 }
1585         } else {
1586                 if (sbi->s_jquota_fmt) {
1587                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1588                                         "specified with no journaling "
1589                                         "enabled");
1590                         return 0;
1591                 }
1592         }
1593 #endif
1594         return 1;
1595 }
1596
1597 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1598                             int read_only)
1599 {
1600         struct ext4_sb_info *sbi = EXT4_SB(sb);
1601         int res = 0;
1602
1603         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1604                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1605                          "forcing read-only mode");
1606                 res = MS_RDONLY;
1607         }
1608         if (read_only)
1609                 return res;
1610         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1611                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1612                          "running e2fsck is recommended");
1613         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1614                 ext4_msg(sb, KERN_WARNING,
1615                          "warning: mounting fs with errors, "
1616                          "running e2fsck is recommended");
1617         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1618                  le16_to_cpu(es->s_mnt_count) >=
1619                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1620                 ext4_msg(sb, KERN_WARNING,
1621                          "warning: maximal mount count reached, "
1622                          "running e2fsck is recommended");
1623         else if (le32_to_cpu(es->s_checkinterval) &&
1624                 (le32_to_cpu(es->s_lastcheck) +
1625                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1626                 ext4_msg(sb, KERN_WARNING,
1627                          "warning: checktime reached, "
1628                          "running e2fsck is recommended");
1629         if (!sbi->s_journal)
1630                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1631         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1632                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1633         le16_add_cpu(&es->s_mnt_count, 1);
1634         es->s_mtime = cpu_to_le32(get_seconds());
1635         ext4_update_dynamic_rev(sb);
1636         if (sbi->s_journal)
1637                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1638
1639         ext4_commit_super(sb, 1);
1640         if (test_opt(sb, DEBUG))
1641                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1642                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1643                         sb->s_blocksize,
1644                         sbi->s_groups_count,
1645                         EXT4_BLOCKS_PER_GROUP(sb),
1646                         EXT4_INODES_PER_GROUP(sb),
1647                         sbi->s_mount_opt);
1648
1649         if (EXT4_SB(sb)->s_journal) {
1650                 ext4_msg(sb, KERN_INFO, "%s journal on %s",
1651                        EXT4_SB(sb)->s_journal->j_inode ? "internal" :
1652                        "external", EXT4_SB(sb)->s_journal->j_devname);
1653         } else {
1654                 ext4_msg(sb, KERN_INFO, "no journal");
1655         }
1656         return res;
1657 }
1658
1659 static int ext4_fill_flex_info(struct super_block *sb)
1660 {
1661         struct ext4_sb_info *sbi = EXT4_SB(sb);
1662         struct ext4_group_desc *gdp = NULL;
1663         ext4_group_t flex_group_count;
1664         ext4_group_t flex_group;
1665         int groups_per_flex = 0;
1666         size_t size;
1667         int i;
1668
1669         if (!sbi->s_es->s_log_groups_per_flex) {
1670                 sbi->s_log_groups_per_flex = 0;
1671                 return 1;
1672         }
1673
1674         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1675         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1676
1677         /* We allocate both existing and potentially added groups */
1678         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1679                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1680                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1681         size = flex_group_count * sizeof(struct flex_groups);
1682         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1683         if (sbi->s_flex_groups == NULL) {
1684                 sbi->s_flex_groups = vmalloc(size);
1685                 if (sbi->s_flex_groups)
1686                         memset(sbi->s_flex_groups, 0, size);
1687         }
1688         if (sbi->s_flex_groups == NULL) {
1689                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1690                                 "%u flex groups", flex_group_count);
1691                 goto failed;
1692         }
1693
1694         for (i = 0; i < sbi->s_groups_count; i++) {
1695                 gdp = ext4_get_group_desc(sb, i, NULL);
1696
1697                 flex_group = ext4_flex_group(sbi, i);
1698                 atomic_add(ext4_free_inodes_count(sb, gdp),
1699                            &sbi->s_flex_groups[flex_group].free_inodes);
1700                 atomic_add(ext4_free_blks_count(sb, gdp),
1701                            &sbi->s_flex_groups[flex_group].free_blocks);
1702                 atomic_add(ext4_used_dirs_count(sb, gdp),
1703                            &sbi->s_flex_groups[flex_group].used_dirs);
1704         }
1705
1706         return 1;
1707 failed:
1708         return 0;
1709 }
1710
1711 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1712                             struct ext4_group_desc *gdp)
1713 {
1714         __u16 crc = 0;
1715
1716         if (sbi->s_es->s_feature_ro_compat &
1717             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1718                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1719                 __le32 le_group = cpu_to_le32(block_group);
1720
1721                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1722                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1723                 crc = crc16(crc, (__u8 *)gdp, offset);
1724                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1725                 /* for checksum of struct ext4_group_desc do the rest...*/
1726                 if ((sbi->s_es->s_feature_incompat &
1727                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1728                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1729                         crc = crc16(crc, (__u8 *)gdp + offset,
1730                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1731                                         offset);
1732         }
1733
1734         return cpu_to_le16(crc);
1735 }
1736
1737 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1738                                 struct ext4_group_desc *gdp)
1739 {
1740         if ((sbi->s_es->s_feature_ro_compat &
1741              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1742             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1743                 return 0;
1744
1745         return 1;
1746 }
1747
1748 /* Called at mount-time, super-block is locked */
1749 static int ext4_check_descriptors(struct super_block *sb)
1750 {
1751         struct ext4_sb_info *sbi = EXT4_SB(sb);
1752         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1753         ext4_fsblk_t last_block;
1754         ext4_fsblk_t block_bitmap;
1755         ext4_fsblk_t inode_bitmap;
1756         ext4_fsblk_t inode_table;
1757         int flexbg_flag = 0;
1758         ext4_group_t i;
1759
1760         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1761                 flexbg_flag = 1;
1762
1763         ext4_debug("Checking group descriptors");
1764
1765         for (i = 0; i < sbi->s_groups_count; i++) {
1766                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1767
1768                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1769                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1770                 else
1771                         last_block = first_block +
1772                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1773
1774                 block_bitmap = ext4_block_bitmap(sb, gdp);
1775                 if (block_bitmap < first_block || block_bitmap > last_block) {
1776                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1777                                "Block bitmap for group %u not in group "
1778                                "(block %llu)!", i, block_bitmap);
1779                         return 0;
1780                 }
1781                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1782                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1783                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1784                                "Inode bitmap for group %u not in group "
1785                                "(block %llu)!", i, inode_bitmap);
1786                         return 0;
1787                 }
1788                 inode_table = ext4_inode_table(sb, gdp);
1789                 if (inode_table < first_block ||
1790                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1791                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1792                                "Inode table for group %u not in group "
1793                                "(block %llu)!", i, inode_table);
1794                         return 0;
1795                 }
1796                 ext4_lock_group(sb, i);
1797                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1798                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1799                                  "Checksum for group %u failed (%u!=%u)",
1800                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1801                                      gdp)), le16_to_cpu(gdp->bg_checksum));
1802                         if (!(sb->s_flags & MS_RDONLY)) {
1803                                 ext4_unlock_group(sb, i);
1804                                 return 0;
1805                         }
1806                 }
1807                 ext4_unlock_group(sb, i);
1808                 if (!flexbg_flag)
1809                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1810         }
1811
1812         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1813         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1814         return 1;
1815 }
1816
1817 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1818  * the superblock) which were deleted from all directories, but held open by
1819  * a process at the time of a crash.  We walk the list and try to delete these
1820  * inodes at recovery time (only with a read-write filesystem).
1821  *
1822  * In order to keep the orphan inode chain consistent during traversal (in
1823  * case of crash during recovery), we link each inode into the superblock
1824  * orphan list_head and handle it the same way as an inode deletion during
1825  * normal operation (which journals the operations for us).
1826  *
1827  * We only do an iget() and an iput() on each inode, which is very safe if we
1828  * accidentally point at an in-use or already deleted inode.  The worst that
1829  * can happen in this case is that we get a "bit already cleared" message from
1830  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1831  * e2fsck was run on this filesystem, and it must have already done the orphan
1832  * inode cleanup for us, so we can safely abort without any further action.
1833  */
1834 static void ext4_orphan_cleanup(struct super_block *sb,
1835                                 struct ext4_super_block *es)
1836 {
1837         unsigned int s_flags = sb->s_flags;
1838         int nr_orphans = 0, nr_truncates = 0;
1839 #ifdef CONFIG_QUOTA
1840         int i;
1841 #endif
1842         if (!es->s_last_orphan) {
1843                 jbd_debug(4, "no orphan inodes to clean up\n");
1844                 return;
1845         }
1846
1847         if (bdev_read_only(sb->s_bdev)) {
1848                 ext4_msg(sb, KERN_ERR, "write access "
1849                         "unavailable, skipping orphan cleanup");
1850                 return;
1851         }
1852
1853         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1854                 if (es->s_last_orphan)
1855                         jbd_debug(1, "Errors on filesystem, "
1856                                   "clearing orphan list.\n");
1857                 es->s_last_orphan = 0;
1858                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1859                 return;
1860         }
1861
1862         if (s_flags & MS_RDONLY) {
1863                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
1864                 sb->s_flags &= ~MS_RDONLY;
1865         }
1866 #ifdef CONFIG_QUOTA
1867         /* Needed for iput() to work correctly and not trash data */
1868         sb->s_flags |= MS_ACTIVE;
1869         /* Turn on quotas so that they are updated correctly */
1870         for (i = 0; i < MAXQUOTAS; i++) {
1871                 if (EXT4_SB(sb)->s_qf_names[i]) {
1872                         int ret = ext4_quota_on_mount(sb, i);
1873                         if (ret < 0)
1874                                 ext4_msg(sb, KERN_ERR,
1875                                         "Cannot turn on journaled "
1876                                         "quota: error %d", ret);
1877                 }
1878         }
1879 #endif
1880
1881         while (es->s_last_orphan) {
1882                 struct inode *inode;
1883
1884                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1885                 if (IS_ERR(inode)) {
1886                         es->s_last_orphan = 0;
1887                         break;
1888                 }
1889
1890                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1891                 vfs_dq_init(inode);
1892                 if (inode->i_nlink) {
1893                         ext4_msg(sb, KERN_DEBUG,
1894                                 "%s: truncating inode %lu to %lld bytes",
1895                                 __func__, inode->i_ino, inode->i_size);
1896                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1897                                   inode->i_ino, inode->i_size);
1898                         ext4_truncate(inode);
1899                         nr_truncates++;
1900                 } else {
1901                         ext4_msg(sb, KERN_DEBUG,
1902                                 "%s: deleting unreferenced inode %lu",
1903                                 __func__, inode->i_ino);
1904                         jbd_debug(2, "deleting unreferenced inode %lu\n",
1905                                   inode->i_ino);
1906                         nr_orphans++;
1907                 }
1908                 iput(inode);  /* The delete magic happens here! */
1909         }
1910
1911 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1912
1913         if (nr_orphans)
1914                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
1915                        PLURAL(nr_orphans));
1916         if (nr_truncates)
1917                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
1918                        PLURAL(nr_truncates));
1919 #ifdef CONFIG_QUOTA
1920         /* Turn quotas off */
1921         for (i = 0; i < MAXQUOTAS; i++) {
1922                 if (sb_dqopt(sb)->files[i])
1923                         vfs_quota_off(sb, i, 0);
1924         }
1925 #endif
1926         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1927 }
1928
1929 /*
1930  * Maximal extent format file size.
1931  * Resulting logical blkno at s_maxbytes must fit in our on-disk
1932  * extent format containers, within a sector_t, and within i_blocks
1933  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
1934  * so that won't be a limiting factor.
1935  *
1936  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1937  */
1938 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1939 {
1940         loff_t res;
1941         loff_t upper_limit = MAX_LFS_FILESIZE;
1942
1943         /* small i_blocks in vfs inode? */
1944         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1945                 /*
1946                  * CONFIG_LBDAF is not enabled implies the inode
1947                  * i_block represent total blocks in 512 bytes
1948                  * 32 == size of vfs inode i_blocks * 8
1949                  */
1950                 upper_limit = (1LL << 32) - 1;
1951
1952                 /* total blocks in file system block size */
1953                 upper_limit >>= (blkbits - 9);
1954                 upper_limit <<= blkbits;
1955         }
1956
1957         /* 32-bit extent-start container, ee_block */
1958         res = 1LL << 32;
1959         res <<= blkbits;
1960         res -= 1;
1961
1962         /* Sanity check against vm- & vfs- imposed limits */
1963         if (res > upper_limit)
1964                 res = upper_limit;
1965
1966         return res;
1967 }
1968
1969 /*
1970  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
1971  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
1972  * We need to be 1 filesystem block less than the 2^48 sector limit.
1973  */
1974 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
1975 {
1976         loff_t res = EXT4_NDIR_BLOCKS;
1977         int meta_blocks;
1978         loff_t upper_limit;
1979         /* This is calculated to be the largest file size for a dense, block
1980          * mapped file such that the file's total number of 512-byte sectors,
1981          * including data and all indirect blocks, does not exceed (2^48 - 1).
1982          *
1983          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
1984          * number of 512-byte sectors of the file.
1985          */
1986
1987         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1988                 /*
1989                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
1990                  * the inode i_block field represents total file blocks in
1991                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
1992                  */
1993                 upper_limit = (1LL << 32) - 1;
1994
1995                 /* total blocks in file system block size */
1996                 upper_limit >>= (bits - 9);
1997
1998         } else {
1999                 /*
2000                  * We use 48 bit ext4_inode i_blocks
2001                  * With EXT4_HUGE_FILE_FL set the i_blocks
2002                  * represent total number of blocks in
2003                  * file system block size
2004                  */
2005                 upper_limit = (1LL << 48) - 1;
2006
2007         }
2008
2009         /* indirect blocks */
2010         meta_blocks = 1;
2011         /* double indirect blocks */
2012         meta_blocks += 1 + (1LL << (bits-2));
2013         /* tripple indirect blocks */
2014         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2015
2016         upper_limit -= meta_blocks;
2017         upper_limit <<= bits;
2018
2019         res += 1LL << (bits-2);
2020         res += 1LL << (2*(bits-2));
2021         res += 1LL << (3*(bits-2));
2022         res <<= bits;
2023         if (res > upper_limit)
2024                 res = upper_limit;
2025
2026         if (res > MAX_LFS_FILESIZE)
2027                 res = MAX_LFS_FILESIZE;
2028
2029         return res;
2030 }
2031
2032 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2033                                    ext4_fsblk_t logical_sb_block, int nr)
2034 {
2035         struct ext4_sb_info *sbi = EXT4_SB(sb);
2036         ext4_group_t bg, first_meta_bg;
2037         int has_super = 0;
2038
2039         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2040
2041         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2042             nr < first_meta_bg)
2043                 return logical_sb_block + nr + 1;
2044         bg = sbi->s_desc_per_block * nr;
2045         if (ext4_bg_has_super(sb, bg))
2046                 has_super = 1;
2047
2048         return (has_super + ext4_group_first_block_no(sb, bg));
2049 }
2050
2051 /**
2052  * ext4_get_stripe_size: Get the stripe size.
2053  * @sbi: In memory super block info
2054  *
2055  * If we have specified it via mount option, then
2056  * use the mount option value. If the value specified at mount time is
2057  * greater than the blocks per group use the super block value.
2058  * If the super block value is greater than blocks per group return 0.
2059  * Allocator needs it be less than blocks per group.
2060  *
2061  */
2062 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2063 {
2064         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2065         unsigned long stripe_width =
2066                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2067
2068         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2069                 return sbi->s_stripe;
2070
2071         if (stripe_width <= sbi->s_blocks_per_group)
2072                 return stripe_width;
2073
2074         if (stride <= sbi->s_blocks_per_group)
2075                 return stride;
2076
2077         return 0;
2078 }
2079
2080 /* sysfs supprt */
2081
2082 struct ext4_attr {
2083         struct attribute attr;
2084         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2085         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *, 
2086                          const char *, size_t);
2087         int offset;
2088 };
2089
2090 static int parse_strtoul(const char *buf,
2091                 unsigned long max, unsigned long *value)
2092 {
2093         char *endp;
2094
2095         while (*buf && isspace(*buf))
2096                 buf++;
2097         *value = simple_strtoul(buf, &endp, 0);
2098         while (*endp && isspace(*endp))
2099                 endp++;
2100         if (*endp || *value > max)
2101                 return -EINVAL;
2102
2103         return 0;
2104 }
2105
2106 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2107                                               struct ext4_sb_info *sbi,
2108                                               char *buf)
2109 {
2110         return snprintf(buf, PAGE_SIZE, "%llu\n",
2111                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2112 }
2113
2114 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2115                                          struct ext4_sb_info *sbi, char *buf)
2116 {
2117         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2118
2119         return snprintf(buf, PAGE_SIZE, "%lu\n",
2120                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2121                          sbi->s_sectors_written_start) >> 1);
2122 }
2123
2124 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2125                                           struct ext4_sb_info *sbi, char *buf)
2126 {
2127         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2128
2129         return snprintf(buf, PAGE_SIZE, "%llu\n",
2130                         sbi->s_kbytes_written + 
2131                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2132                           EXT4_SB(sb)->s_sectors_written_start) >> 1));
2133 }
2134
2135 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2136                                           struct ext4_sb_info *sbi,
2137                                           const char *buf, size_t count)
2138 {
2139         unsigned long t;
2140
2141         if (parse_strtoul(buf, 0x40000000, &t))
2142                 return -EINVAL;
2143
2144         if (!is_power_of_2(t))
2145                 return -EINVAL;
2146
2147         sbi->s_inode_readahead_blks = t;
2148         return count;
2149 }
2150
2151 static ssize_t sbi_ui_show(struct ext4_attr *a,
2152                            struct ext4_sb_info *sbi, char *buf)
2153 {
2154         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2155
2156         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2157 }
2158
2159 static ssize_t sbi_ui_store(struct ext4_attr *a,
2160                             struct ext4_sb_info *sbi,
2161                             const char *buf, size_t count)
2162 {
2163         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2164         unsigned long t;
2165
2166         if (parse_strtoul(buf, 0xffffffff, &t))
2167                 return -EINVAL;
2168         *ui = t;
2169         return count;
2170 }
2171
2172 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2173 static struct ext4_attr ext4_attr_##_name = {                   \
2174         .attr = {.name = __stringify(_name), .mode = _mode },   \
2175         .show   = _show,                                        \
2176         .store  = _store,                                       \
2177         .offset = offsetof(struct ext4_sb_info, _elname),       \
2178 }
2179 #define EXT4_ATTR(name, mode, show, store) \
2180 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2181
2182 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2183 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2184 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2185         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2186 #define ATTR_LIST(name) &ext4_attr_##name.attr
2187
2188 EXT4_RO_ATTR(delayed_allocation_blocks);
2189 EXT4_RO_ATTR(session_write_kbytes);
2190 EXT4_RO_ATTR(lifetime_write_kbytes);
2191 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2192                  inode_readahead_blks_store, s_inode_readahead_blks);
2193 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2194 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2195 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2196 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2197 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2198 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2199 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2200 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2201
2202 static struct attribute *ext4_attrs[] = {
2203         ATTR_LIST(delayed_allocation_blocks),
2204         ATTR_LIST(session_write_kbytes),
2205         ATTR_LIST(lifetime_write_kbytes),
2206         ATTR_LIST(inode_readahead_blks),
2207         ATTR_LIST(inode_goal),
2208         ATTR_LIST(mb_stats),
2209         ATTR_LIST(mb_max_to_scan),
2210         ATTR_LIST(mb_min_to_scan),
2211         ATTR_LIST(mb_order2_req),
2212         ATTR_LIST(mb_stream_req),
2213         ATTR_LIST(mb_group_prealloc),
2214         ATTR_LIST(max_writeback_mb_bump),
2215         NULL,
2216 };
2217
2218 static ssize_t ext4_attr_show(struct kobject *kobj,
2219                               struct attribute *attr, char *buf)
2220 {
2221         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2222                                                 s_kobj);
2223         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2224
2225         return a->show ? a->show(a, sbi, buf) : 0;
2226 }
2227
2228 static ssize_t ext4_attr_store(struct kobject *kobj,
2229                                struct attribute *attr,
2230                                const char *buf, size_t len)
2231 {
2232         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2233                                                 s_kobj);
2234         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2235
2236         return a->store ? a->store(a, sbi, buf, len) : 0;
2237 }
2238
2239 static void ext4_sb_release(struct kobject *kobj)
2240 {
2241         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2242                                                 s_kobj);
2243         complete(&sbi->s_kobj_unregister);
2244 }
2245
2246
2247 static struct sysfs_ops ext4_attr_ops = {
2248         .show   = ext4_attr_show,
2249         .store  = ext4_attr_store,
2250 };
2251
2252 static struct kobj_type ext4_ktype = {
2253         .default_attrs  = ext4_attrs,
2254         .sysfs_ops      = &ext4_attr_ops,
2255         .release        = ext4_sb_release,
2256 };
2257
2258 /*
2259  * Check whether this filesystem can be mounted based on
2260  * the features present and the RDONLY/RDWR mount requested.
2261  * Returns 1 if this filesystem can be mounted as requested,
2262  * 0 if it cannot be.
2263  */
2264 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2265 {
2266         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2267                 ext4_msg(sb, KERN_ERR,
2268                         "Couldn't mount because of "
2269                         "unsupported optional features (%x)",
2270                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2271                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2272                 return 0;
2273         }
2274
2275         if (readonly)
2276                 return 1;
2277
2278         /* Check that feature set is OK for a read-write mount */
2279         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2280                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2281                          "unsupported optional features (%x)",
2282                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2283                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2284                 return 0;
2285         }
2286         /*
2287          * Large file size enabled file system can only be mounted
2288          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2289          */
2290         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2291                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2292                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2293                                  "cannot be mounted RDWR without "
2294                                  "CONFIG_LBDAF");
2295                         return 0;
2296                 }
2297         }
2298         return 1;
2299 }
2300
2301 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2302                                 __releases(kernel_lock)
2303                                 __acquires(kernel_lock)
2304 {
2305         struct buffer_head *bh;
2306         struct ext4_super_block *es = NULL;
2307         struct ext4_sb_info *sbi;
2308         ext4_fsblk_t block;
2309         ext4_fsblk_t sb_block = get_sb_block(&data);
2310         ext4_fsblk_t logical_sb_block;
2311         unsigned long offset = 0;
2312         unsigned long journal_devnum = 0;
2313         unsigned long def_mount_opts;
2314         struct inode *root;
2315         char *cp;
2316         const char *descr;
2317         int ret = -EINVAL;
2318         int blocksize;
2319         unsigned int db_count;
2320         unsigned int i;
2321         int needs_recovery, has_huge_files;
2322         __u64 blocks_count;
2323         int err;
2324         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2325
2326         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2327         if (!sbi)
2328                 return -ENOMEM;
2329
2330         sbi->s_blockgroup_lock =
2331                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2332         if (!sbi->s_blockgroup_lock) {
2333                 kfree(sbi);
2334                 return -ENOMEM;
2335         }
2336         sb->s_fs_info = sbi;
2337         sbi->s_mount_opt = 0;
2338         sbi->s_resuid = EXT4_DEF_RESUID;
2339         sbi->s_resgid = EXT4_DEF_RESGID;
2340         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2341         sbi->s_sb_block = sb_block;
2342         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2343                                                       sectors[1]);
2344
2345         unlock_kernel();
2346
2347         /* Cleanup superblock name */
2348         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2349                 *cp = '!';
2350
2351         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2352         if (!blocksize) {
2353                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2354                 goto out_fail;
2355         }
2356
2357         /*
2358          * The ext4 superblock will not be buffer aligned for other than 1kB
2359          * block sizes.  We need to calculate the offset from buffer start.
2360          */
2361         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2362                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2363                 offset = do_div(logical_sb_block, blocksize);
2364         } else {
2365                 logical_sb_block = sb_block;
2366         }
2367
2368         if (!(bh = sb_bread(sb, logical_sb_block))) {
2369                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2370                 goto out_fail;
2371         }
2372         /*
2373          * Note: s_es must be initialized as soon as possible because
2374          *       some ext4 macro-instructions depend on its value
2375          */
2376         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2377         sbi->s_es = es;
2378         sb->s_magic = le16_to_cpu(es->s_magic);
2379         if (sb->s_magic != EXT4_SUPER_MAGIC)
2380                 goto cantfind_ext4;
2381         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2382
2383         /* Set defaults before we parse the mount options */
2384         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2385         if (def_mount_opts & EXT4_DEFM_DEBUG)
2386                 set_opt(sbi->s_mount_opt, DEBUG);
2387         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
2388                 set_opt(sbi->s_mount_opt, GRPID);
2389         if (def_mount_opts & EXT4_DEFM_UID16)
2390                 set_opt(sbi->s_mount_opt, NO_UID32);
2391 #ifdef CONFIG_EXT4_FS_XATTR
2392         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2393                 set_opt(sbi->s_mount_opt, XATTR_USER);
2394 #endif
2395 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2396         if (def_mount_opts & EXT4_DEFM_ACL)
2397                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2398 #endif
2399         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2400                 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2401         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2402                 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2403         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2404                 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2405
2406         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2407                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2408         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2409                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2410         else
2411                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2412
2413         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2414         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2415         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2416         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2417         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2418         sbi->s_mb_history_max = default_mb_history_length;
2419
2420         set_opt(sbi->s_mount_opt, BARRIER);
2421
2422         /*
2423          * enable delayed allocation by default
2424          * Use -o nodelalloc to turn it off
2425          */
2426         set_opt(sbi->s_mount_opt, DELALLOC);
2427
2428         if (!parse_options((char *) data, sb, &journal_devnum,
2429                            &journal_ioprio, NULL, 0))
2430                 goto failed_mount;
2431
2432         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2433                 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2434
2435         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2436             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2437              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2438              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2439                 ext4_msg(sb, KERN_WARNING,
2440                        "feature flags set on rev 0 fs, "
2441                        "running e2fsck is recommended");
2442
2443         /*
2444          * Check feature flags regardless of the revision level, since we
2445          * previously didn't change the revision level when setting the flags,
2446          * so there is a chance incompat flags are set on a rev 0 filesystem.
2447          */
2448         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
2449                 goto failed_mount;
2450
2451         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2452
2453         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2454             blocksize > EXT4_MAX_BLOCK_SIZE) {
2455                 ext4_msg(sb, KERN_ERR,
2456                        "Unsupported filesystem blocksize %d", blocksize);
2457                 goto failed_mount;
2458         }
2459
2460         if (sb->s_blocksize != blocksize) {
2461                 /* Validate the filesystem blocksize */
2462                 if (!sb_set_blocksize(sb, blocksize)) {
2463                         ext4_msg(sb, KERN_ERR, "bad block size %d",
2464                                         blocksize);
2465                         goto failed_mount;
2466                 }
2467
2468                 brelse(bh);
2469                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2470                 offset = do_div(logical_sb_block, blocksize);
2471                 bh = sb_bread(sb, logical_sb_block);
2472                 if (!bh) {
2473                         ext4_msg(sb, KERN_ERR,
2474                                "Can't read superblock on 2nd try");
2475                         goto failed_mount;
2476                 }
2477                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2478                 sbi->s_es = es;
2479                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2480                         ext4_msg(sb, KERN_ERR,
2481                                "Magic mismatch, very weird!");
2482                         goto failed_mount;
2483                 }
2484         }
2485
2486         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2487                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2488         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2489                                                       has_huge_files);
2490         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2491
2492         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2493                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2494                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2495         } else {
2496                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2497                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2498                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2499                     (!is_power_of_2(sbi->s_inode_size)) ||
2500                     (sbi->s_inode_size > blocksize)) {
2501                         ext4_msg(sb, KERN_ERR,
2502                                "unsupported inode size: %d",
2503                                sbi->s_inode_size);
2504                         goto failed_mount;
2505                 }
2506                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2507                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2508         }
2509
2510         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2511         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2512                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2513                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2514                     !is_power_of_2(sbi->s_desc_size)) {
2515                         ext4_msg(sb, KERN_ERR,
2516                                "unsupported descriptor size %lu",
2517                                sbi->s_desc_size);
2518                         goto failed_mount;
2519                 }
2520         } else
2521                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2522
2523         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2524         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2525         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2526                 goto cantfind_ext4;
2527
2528         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2529         if (sbi->s_inodes_per_block == 0)
2530                 goto cantfind_ext4;
2531         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2532                                         sbi->s_inodes_per_block;
2533         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2534         sbi->s_sbh = bh;
2535         sbi->s_mount_state = le16_to_cpu(es->s_state);
2536         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2537         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2538
2539         for (i = 0; i < 4; i++)
2540                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2541         sbi->s_def_hash_version = es->s_def_hash_version;
2542         i = le32_to_cpu(es->s_flags);
2543         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2544                 sbi->s_hash_unsigned = 3;
2545         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2546 #ifdef __CHAR_UNSIGNED__
2547                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2548                 sbi->s_hash_unsigned = 3;
2549 #else
2550                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2551 #endif
2552                 sb->s_dirt = 1;
2553         }
2554
2555         if (sbi->s_blocks_per_group > blocksize * 8) {
2556                 ext4_msg(sb, KERN_ERR,
2557                        "#blocks per group too big: %lu",
2558                        sbi->s_blocks_per_group);
2559                 goto failed_mount;
2560         }
2561         if (sbi->s_inodes_per_group > blocksize * 8) {
2562                 ext4_msg(sb, KERN_ERR,
2563                        "#inodes per group too big: %lu",
2564                        sbi->s_inodes_per_group);
2565                 goto failed_mount;
2566         }
2567
2568         /*
2569          * Test whether we have more sectors than will fit in sector_t,
2570          * and whether the max offset is addressable by the page cache.
2571          */
2572         if ((ext4_blocks_count(es) >
2573              (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
2574             (ext4_blocks_count(es) >
2575              (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
2576                 ext4_msg(sb, KERN_ERR, "filesystem"
2577                          " too large to mount safely on this system");
2578                 if (sizeof(sector_t) < 8)
2579                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
2580                 ret = -EFBIG;
2581                 goto failed_mount;
2582         }
2583
2584         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2585                 goto cantfind_ext4;
2586
2587         /* check blocks count against device size */
2588         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2589         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2590                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2591                        "exceeds size of device (%llu blocks)",
2592                        ext4_blocks_count(es), blocks_count);
2593                 goto failed_mount;
2594         }
2595
2596         /*
2597          * It makes no sense for the first data block to be beyond the end
2598          * of the filesystem.
2599          */
2600         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2601                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2602                          "block %u is beyond end of filesystem (%llu)",
2603                          le32_to_cpu(es->s_first_data_block),
2604                          ext4_blocks_count(es));
2605                 goto failed_mount;
2606         }
2607         blocks_count = (ext4_blocks_count(es) -
2608                         le32_to_cpu(es->s_first_data_block) +
2609                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2610         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2611         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2612                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2613                        "(block count %llu, first data block %u, "
2614                        "blocks per group %lu)", sbi->s_groups_count,
2615                        ext4_blocks_count(es),
2616                        le32_to_cpu(es->s_first_data_block),
2617                        EXT4_BLOCKS_PER_GROUP(sb));
2618                 goto failed_mount;
2619         }
2620         sbi->s_groups_count = blocks_count;
2621         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
2622                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
2623         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2624                    EXT4_DESC_PER_BLOCK(sb);
2625         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2626                                     GFP_KERNEL);
2627         if (sbi->s_group_desc == NULL) {
2628                 ext4_msg(sb, KERN_ERR, "not enough memory");
2629                 goto failed_mount;
2630         }
2631
2632 #ifdef CONFIG_PROC_FS
2633         if (ext4_proc_root)
2634                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2635 #endif
2636
2637         bgl_lock_init(sbi->s_blockgroup_lock);
2638
2639         for (i = 0; i < db_count; i++) {
2640                 block = descriptor_loc(sb, logical_sb_block, i);
2641                 sbi->s_group_desc[i] = sb_bread(sb, block);
2642                 if (!sbi->s_group_desc[i]) {
2643                         ext4_msg(sb, KERN_ERR,
2644                                "can't read group descriptor %d", i);
2645                         db_count = i;
2646                         goto failed_mount2;
2647                 }
2648         }
2649         if (!ext4_check_descriptors(sb)) {
2650                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2651                 goto failed_mount2;
2652         }
2653         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2654                 if (!ext4_fill_flex_info(sb)) {
2655                         ext4_msg(sb, KERN_ERR,
2656                                "unable to initialize "
2657                                "flex_bg meta info!");
2658                         goto failed_mount2;
2659                 }
2660
2661         sbi->s_gdb_count = db_count;
2662         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2663         spin_lock_init(&sbi->s_next_gen_lock);
2664
2665         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2666                         ext4_count_free_blocks(sb));
2667         if (!err) {
2668                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2669                                 ext4_count_free_inodes(sb));
2670         }
2671         if (!err) {
2672                 err = percpu_counter_init(&sbi->s_dirs_counter,
2673                                 ext4_count_dirs(sb));
2674         }
2675         if (!err) {
2676                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2677         }
2678         if (err) {
2679                 ext4_msg(sb, KERN_ERR, "insufficient memory");
2680                 goto failed_mount3;
2681         }
2682
2683         sbi->s_stripe = ext4_get_stripe_size(sbi);
2684         sbi->s_max_writeback_mb_bump = 128;
2685
2686         /*
2687          * set up enough so that it can read an inode
2688          */
2689         if (!test_opt(sb, NOLOAD) &&
2690             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2691                 sb->s_op = &ext4_sops;
2692         else
2693                 sb->s_op = &ext4_nojournal_sops;
2694         sb->s_export_op = &ext4_export_ops;
2695         sb->s_xattr = ext4_xattr_handlers;
2696 #ifdef CONFIG_QUOTA
2697         sb->s_qcop = &ext4_qctl_operations;
2698         sb->dq_op = &ext4_quota_operations;
2699 #endif
2700         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2701         mutex_init(&sbi->s_orphan_lock);
2702         mutex_init(&sbi->s_resize_lock);
2703
2704         sb->s_root = NULL;
2705
2706         needs_recovery = (es->s_last_orphan != 0 ||
2707                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2708                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2709
2710         /*
2711          * The first inode we look at is the journal inode.  Don't try
2712          * root first: it may be modified in the journal!
2713          */
2714         if (!test_opt(sb, NOLOAD) &&
2715             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2716                 if (ext4_load_journal(sb, es, journal_devnum))
2717                         goto failed_mount3;
2718                 if (!(sb->s_flags & MS_RDONLY) &&
2719                     EXT4_SB(sb)->s_journal->j_failed_commit) {
2720                         ext4_msg(sb, KERN_CRIT, "error: "
2721                                "ext4_fill_super: Journal transaction "
2722                                "%u is corrupt",
2723                                EXT4_SB(sb)->s_journal->j_failed_commit);
2724                         if (test_opt(sb, ERRORS_RO)) {
2725                                 ext4_msg(sb, KERN_CRIT,
2726                                        "Mounting filesystem read-only");
2727                                 sb->s_flags |= MS_RDONLY;
2728                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2729                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2730                         }
2731                         if (test_opt(sb, ERRORS_PANIC)) {
2732                                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
2733                                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
2734                                 ext4_commit_super(sb, 1);
2735                                 goto failed_mount4;
2736                         }
2737                 }
2738         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2739               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2740                 ext4_msg(sb, KERN_ERR, "required journal recovery "
2741                        "suppressed and not mounted read-only");
2742                 goto failed_mount4;
2743         } else {
2744                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2745                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2746                 sbi->s_journal = NULL;
2747                 needs_recovery = 0;
2748                 goto no_journal;
2749         }
2750
2751         if (ext4_blocks_count(es) > 0xffffffffULL &&
2752             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2753                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2754                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
2755                 goto failed_mount4;
2756         }
2757
2758         jbd2_journal_set_features(sbi->s_journal,
2759                                   JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2760         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
2761                 jbd2_journal_set_features(sbi->s_journal, 0, 0,
2762                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2763         else
2764                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2765                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2766
2767         /* We have now updated the journal if required, so we can
2768          * validate the data journaling mode. */
2769         switch (test_opt(sb, DATA_FLAGS)) {
2770         case 0:
2771                 /* No mode set, assume a default based on the journal
2772                  * capabilities: ORDERED_DATA if the journal can
2773                  * cope, else JOURNAL_DATA
2774                  */
2775                 if (jbd2_journal_check_available_features
2776                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2777                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2778                 else
2779                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2780                 break;
2781
2782         case EXT4_MOUNT_ORDERED_DATA:
2783         case EXT4_MOUNT_WRITEBACK_DATA:
2784                 if (!jbd2_journal_check_available_features
2785                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2786                         ext4_msg(sb, KERN_ERR, "Journal does not support "
2787                                "requested data journaling mode");
2788                         goto failed_mount4;
2789                 }
2790         default:
2791                 break;
2792         }
2793         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2794
2795 no_journal:
2796
2797         if (test_opt(sb, NOBH)) {
2798                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2799                         ext4_msg(sb, KERN_WARNING, "Ignoring nobh option - "
2800                                 "its supported only with writeback mode");
2801                         clear_opt(sbi->s_mount_opt, NOBH);
2802                 }
2803         }
2804         /*
2805          * The jbd2_journal_load will have done any necessary log recovery,
2806          * so we can safely mount the rest of the filesystem now.
2807          */
2808
2809         root = ext4_iget(sb, EXT4_ROOT_INO);
2810         if (IS_ERR(root)) {
2811                 ext4_msg(sb, KERN_ERR, "get root inode failed");
2812                 ret = PTR_ERR(root);
2813                 goto failed_mount4;
2814         }
2815         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2816                 iput(root);
2817                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
2818                 goto failed_mount4;
2819         }
2820         sb->s_root = d_alloc_root(root);
2821         if (!sb->s_root) {
2822                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
2823                 iput(root);
2824                 ret = -ENOMEM;
2825                 goto failed_mount4;
2826         }
2827
2828         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2829
2830         /* determine the minimum size of new large inodes, if present */
2831         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2832                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2833                                                      EXT4_GOOD_OLD_INODE_SIZE;
2834                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2835                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2836                         if (sbi->s_want_extra_isize <
2837                             le16_to_cpu(es->s_want_extra_isize))
2838                                 sbi->s_want_extra_isize =
2839                                         le16_to_cpu(es->s_want_extra_isize);
2840                         if (sbi->s_want_extra_isize <
2841                             le16_to_cpu(es->s_min_extra_isize))
2842                                 sbi->s_want_extra_isize =
2843                                         le16_to_cpu(es->s_min_extra_isize);
2844                 }
2845         }
2846         /* Check if enough inode space is available */
2847         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2848                                                         sbi->s_inode_size) {
2849                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2850                                                        EXT4_GOOD_OLD_INODE_SIZE;
2851                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
2852                          "available");
2853         }
2854
2855         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2856                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
2857                          "requested data journaling mode");
2858                 clear_opt(sbi->s_mount_opt, DELALLOC);
2859         } else if (test_opt(sb, DELALLOC))
2860                 ext4_msg(sb, KERN_INFO, "delayed allocation enabled");
2861
2862         err = ext4_setup_system_zone(sb);
2863         if (err) {
2864                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
2865                          "zone (%d)\n", err);
2866                 goto failed_mount4;
2867         }
2868
2869         ext4_ext_init(sb);
2870         err = ext4_mb_init(sb, needs_recovery);
2871         if (err) {
2872                 ext4_msg(sb, KERN_ERR, "failed to initalize mballoc (%d)",
2873                          err);
2874                 goto failed_mount4;
2875         }
2876
2877         sbi->s_kobj.kset = ext4_kset;
2878         init_completion(&sbi->s_kobj_unregister);
2879         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
2880                                    "%s", sb->s_id);
2881         if (err) {
2882                 ext4_mb_release(sb);
2883                 ext4_ext_release(sb);
2884                 goto failed_mount4;
2885         };
2886
2887         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2888         ext4_orphan_cleanup(sb, es);
2889         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2890         if (needs_recovery) {
2891                 ext4_msg(sb, KERN_INFO, "recovery complete");
2892                 ext4_mark_recovery_complete(sb, es);
2893         }
2894         if (EXT4_SB(sb)->s_journal) {
2895                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2896                         descr = " journalled data mode";
2897                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2898                         descr = " ordered data mode";
2899                 else
2900                         descr = " writeback data mode";
2901         } else
2902                 descr = "out journal";
2903
2904         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s", descr);
2905
2906         lock_kernel();
2907         return 0;
2908
2909 cantfind_ext4:
2910         if (!silent)
2911                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
2912         goto failed_mount;
2913
2914 failed_mount4:
2915         ext4_msg(sb, KERN_ERR, "mount failed");
2916         ext4_release_system_zone(sb);
2917         if (sbi->s_journal) {
2918                 jbd2_journal_destroy(sbi->s_journal);
2919                 sbi->s_journal = NULL;
2920         }
2921 failed_mount3:
2922         if (sbi->s_flex_groups) {
2923                 if (is_vmalloc_addr(sbi->s_flex_groups))
2924                         vfree(sbi->s_flex_groups);
2925                 else
2926                         kfree(sbi->s_flex_groups);
2927         }
2928         percpu_counter_destroy(&sbi->s_freeblocks_counter);
2929         percpu_counter_destroy(&sbi->s_freeinodes_counter);
2930         percpu_counter_destroy(&sbi->s_dirs_counter);
2931         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2932 failed_mount2:
2933         for (i = 0; i < db_count; i++)
2934                 brelse(sbi->s_group_desc[i]);
2935         kfree(sbi->s_group_desc);
2936 failed_mount:
2937         if (sbi->s_proc) {
2938                 remove_proc_entry(sb->s_id, ext4_proc_root);
2939         }
2940 #ifdef CONFIG_QUOTA
2941         for (i = 0; i < MAXQUOTAS; i++)
2942                 kfree(sbi->s_qf_names[i]);
2943 #endif
2944         ext4_blkdev_remove(sbi);
2945         brelse(bh);
2946 out_fail:
2947         sb->s_fs_info = NULL;
2948         kfree(sbi->s_blockgroup_lock);
2949         kfree(sbi);
2950         lock_kernel();
2951         return ret;
2952 }
2953
2954 /*
2955  * Setup any per-fs journal parameters now.  We'll do this both on
2956  * initial mount, once the journal has been initialised but before we've
2957  * done any recovery; and again on any subsequent remount.
2958  */
2959 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2960 {
2961         struct ext4_sb_info *sbi = EXT4_SB(sb);
2962
2963         journal->j_commit_interval = sbi->s_commit_interval;
2964         journal->j_min_batch_time = sbi->s_min_batch_time;
2965         journal->j_max_batch_time = sbi->s_max_batch_time;
2966
2967         spin_lock(&journal->j_state_lock);
2968         if (test_opt(sb, BARRIER))
2969                 journal->j_flags |= JBD2_BARRIER;
2970         else
2971                 journal->j_flags &= ~JBD2_BARRIER;
2972         if (test_opt(sb, DATA_ERR_ABORT))
2973                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
2974         else
2975                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
2976         spin_unlock(&journal->j_state_lock);
2977 }
2978
2979 static journal_t *ext4_get_journal(struct super_block *sb,
2980                                    unsigned int journal_inum)
2981 {
2982         struct inode *journal_inode;
2983         journal_t *journal;
2984
2985         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
2986
2987         /* First, test for the existence of a valid inode on disk.  Bad
2988          * things happen if we iget() an unused inode, as the subsequent
2989          * iput() will try to delete it. */
2990
2991         journal_inode = ext4_iget(sb, journal_inum);
2992         if (IS_ERR(journal_inode)) {
2993                 ext4_msg(sb, KERN_ERR, "no journal found");
2994                 return NULL;
2995         }
2996         if (!journal_inode->i_nlink) {
2997                 make_bad_inode(journal_inode);
2998                 iput(journal_inode);
2999                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3000                 return NULL;
3001         }
3002
3003         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3004                   journal_inode, journal_inode->i_size);
3005         if (!S_ISREG(journal_inode->i_mode)) {
3006                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3007                 iput(journal_inode);
3008                 return NULL;
3009         }
3010
3011         journal = jbd2_journal_init_inode(journal_inode);
3012         if (!journal) {
3013                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3014                 iput(journal_inode);
3015                 return NULL;
3016         }
3017         journal->j_private = sb;
3018         ext4_init_journal_params(sb, journal);
3019         return journal;
3020 }
3021
3022 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3023                                        dev_t j_dev)
3024 {
3025         struct buffer_head *bh;
3026         journal_t *journal;
3027         ext4_fsblk_t start;
3028         ext4_fsblk_t len;
3029         int hblock, blocksize;
3030         ext4_fsblk_t sb_block;
3031         unsigned long offset;
3032         struct ext4_super_block *es;
3033         struct block_device *bdev;
3034
3035         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3036
3037         bdev = ext4_blkdev_get(j_dev, sb);
3038         if (bdev == NULL)
3039                 return NULL;
3040
3041         if (bd_claim(bdev, sb)) {
3042                 ext4_msg(sb, KERN_ERR,
3043                         "failed to claim external journal device");
3044                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3045                 return NULL;
3046         }
3047
3048         blocksize = sb->s_blocksize;
3049         hblock = bdev_logical_block_size(bdev);
3050         if (blocksize < hblock) {
3051                 ext4_msg(sb, KERN_ERR,
3052                         "blocksize too small for journal device");
3053                 goto out_bdev;
3054         }
3055
3056         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3057         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3058         set_blocksize(bdev, blocksize);
3059         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3060                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3061                        "external journal");
3062                 goto out_bdev;
3063         }
3064
3065         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3066         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3067             !(le32_to_cpu(es->s_feature_incompat) &
3068               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3069                 ext4_msg(sb, KERN_ERR, "external journal has "
3070                                         "bad superblock");
3071                 brelse(bh);
3072                 goto out_bdev;
3073         }
3074
3075         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3076                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3077                 brelse(bh);
3078                 goto out_bdev;
3079         }
3080
3081         len = ext4_blocks_count(es);
3082         start = sb_block + 1;
3083         brelse(bh);     /* we're done with the superblock */
3084
3085         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3086                                         start, len, blocksize);
3087         if (!journal) {
3088                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3089                 goto out_bdev;
3090         }
3091         journal->j_private = sb;
3092         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3093         wait_on_buffer(journal->j_sb_buffer);
3094         if (!buffer_uptodate(journal->j_sb_buffer)) {
3095                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3096                 goto out_journal;
3097         }
3098         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3099                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3100                                         "user (unsupported) - %d",
3101                         be32_to_cpu(journal->j_superblock->s_nr_users));
3102                 goto out_journal;
3103         }
3104         EXT4_SB(sb)->journal_bdev = bdev;
3105         ext4_init_journal_params(sb, journal);
3106         return journal;
3107
3108 out_journal:
3109         jbd2_journal_destroy(journal);
3110 out_bdev:
3111         ext4_blkdev_put(bdev);
3112         return NULL;
3113 }
3114
3115 static int ext4_load_journal(struct super_block *sb,
3116                              struct ext4_super_block *es,
3117                              unsigned long journal_devnum)
3118 {
3119         journal_t *journal;
3120         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3121         dev_t journal_dev;
3122         int err = 0;
3123         int really_read_only;
3124
3125         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3126
3127         if (journal_devnum &&
3128             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3129                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3130                         "numbers have changed");
3131                 journal_dev = new_decode_dev(journal_devnum);
3132         } else
3133                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3134
3135         really_read_only = bdev_read_only(sb->s_bdev);
3136
3137         /*
3138          * Are we loading a blank journal or performing recovery after a
3139          * crash?  For recovery, we need to check in advance whether we
3140          * can get read-write access to the device.
3141          */
3142         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3143                 if (sb->s_flags & MS_RDONLY) {
3144                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3145                                         "required on readonly filesystem");
3146                         if (really_read_only) {
3147                                 ext4_msg(sb, KERN_ERR, "write access "
3148                                         "unavailable, cannot proceed");
3149                                 return -EROFS;
3150                         }
3151                         ext4_msg(sb, KERN_INFO, "write access will "
3152                                "be enabled during recovery");
3153                 }
3154         }
3155
3156         if (journal_inum && journal_dev) {
3157                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3158                        "and inode journals!");
3159                 return -EINVAL;
3160         }
3161
3162         if (journal_inum) {
3163                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3164                         return -EINVAL;
3165         } else {
3166                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3167                         return -EINVAL;
3168         }
3169
3170         if (journal->j_flags & JBD2_BARRIER)
3171                 ext4_msg(sb, KERN_INFO, "barriers enabled");
3172         else
3173                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3174
3175         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3176                 err = jbd2_journal_update_format(journal);
3177                 if (err)  {
3178                         ext4_msg(sb, KERN_ERR, "error updating journal");
3179                         jbd2_journal_destroy(journal);
3180                         return err;
3181                 }
3182         }
3183
3184         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3185                 err = jbd2_journal_wipe(journal, !really_read_only);
3186         if (!err)
3187                 err = jbd2_journal_load(journal);
3188
3189         if (err) {
3190                 ext4_msg(sb, KERN_ERR, "error loading journal");
3191                 jbd2_journal_destroy(journal);
3192                 return err;
3193         }
3194
3195         EXT4_SB(sb)->s_journal = journal;
3196         ext4_clear_journal_err(sb, es);
3197
3198         if (journal_devnum &&
3199             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3200                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3201
3202                 /* Make sure we flush the recovery flag to disk. */
3203                 ext4_commit_super(sb, 1);
3204         }
3205
3206         return 0;
3207 }
3208
3209 static int ext4_commit_super(struct super_block *sb, int sync)
3210 {
3211         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3212         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3213         int error = 0;
3214
3215         if (!sbh)
3216                 return error;
3217         if (buffer_write_io_error(sbh)) {
3218                 /*
3219                  * Oh, dear.  A previous attempt to write the
3220                  * superblock failed.  This could happen because the
3221                  * USB device was yanked out.  Or it could happen to
3222                  * be a transient write error and maybe the block will
3223                  * be remapped.  Nothing we can do but to retry the
3224                  * write and hope for the best.
3225                  */
3226                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3227                        "superblock detected");
3228                 clear_buffer_write_io_error(sbh);
3229                 set_buffer_uptodate(sbh);
3230         }
3231         /*
3232          * If the file system is mounted read-only, don't update the
3233          * superblock write time.  This avoids updating the superblock
3234          * write time when we are mounting the root file system
3235          * read/only but we need to replay the journal; at that point,
3236          * for people who are east of GMT and who make their clock
3237          * tick in localtime for Windows bug-for-bug compatibility,
3238          * the clock is set in the future, and this will cause e2fsck
3239          * to complain and force a full file system check.
3240          */
3241         if (!(sb->s_flags & MS_RDONLY))
3242                 es->s_wtime = cpu_to_le32(get_seconds());
3243         es->s_kbytes_written =
3244                 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written + 
3245                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3246                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
3247         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3248                                         &EXT4_SB(sb)->s_freeblocks_counter));