quota: drop remount argument to ->quota_on and ->quota_off
[linux-2.6.git] / fs / ext4 / super.c
1 /*
2  *  linux/fs/ext4/super.c
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/fs/minix/inode.c
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  *
15  *  Big-endian to little-endian byte-swapping/bitmaps by
16  *        David S. Miller (davem@caip.rutgers.edu), 1995
17  */
18
19 #include <linux/module.h>
20 #include <linux/string.h>
21 #include <linux/fs.h>
22 #include <linux/time.h>
23 #include <linux/vmalloc.h>
24 #include <linux/jbd2.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/parser.h>
29 #include <linux/smp_lock.h>
30 #include <linux/buffer_head.h>
31 #include <linux/exportfs.h>
32 #include <linux/vfs.h>
33 #include <linux/random.h>
34 #include <linux/mount.h>
35 #include <linux/namei.h>
36 #include <linux/quotaops.h>
37 #include <linux/seq_file.h>
38 #include <linux/proc_fs.h>
39 #include <linux/ctype.h>
40 #include <linux/log2.h>
41 #include <linux/crc16.h>
42 #include <asm/uaccess.h>
43
44 #include "ext4.h"
45 #include "ext4_jbd2.h"
46 #include "xattr.h"
47 #include "acl.h"
48 #include "mballoc.h"
49
50 #define CREATE_TRACE_POINTS
51 #include <trace/events/ext4.h>
52
53 struct proc_dir_entry *ext4_proc_root;
54 static struct kset *ext4_kset;
55
56 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
57                              unsigned long journal_devnum);
58 static int ext4_commit_super(struct super_block *sb, int sync);
59 static void ext4_mark_recovery_complete(struct super_block *sb,
60                                         struct ext4_super_block *es);
61 static void ext4_clear_journal_err(struct super_block *sb,
62                                    struct ext4_super_block *es);
63 static int ext4_sync_fs(struct super_block *sb, int wait);
64 static const char *ext4_decode_error(struct super_block *sb, int errno,
65                                      char nbuf[16]);
66 static int ext4_remount(struct super_block *sb, int *flags, char *data);
67 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
68 static int ext4_unfreeze(struct super_block *sb);
69 static void ext4_write_super(struct super_block *sb);
70 static int ext4_freeze(struct super_block *sb);
71 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
72                        const char *dev_name, void *data, struct vfsmount *mnt);
73
74 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
75 static struct file_system_type ext3_fs_type = {
76         .owner          = THIS_MODULE,
77         .name           = "ext3",
78         .get_sb         = ext4_get_sb,
79         .kill_sb        = kill_block_super,
80         .fs_flags       = FS_REQUIRES_DEV,
81 };
82 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
83 #else
84 #define IS_EXT3_SB(sb) (0)
85 #endif
86
87 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
88                                struct ext4_group_desc *bg)
89 {
90         return le32_to_cpu(bg->bg_block_bitmap_lo) |
91                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
92                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
93 }
94
95 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
96                                struct ext4_group_desc *bg)
97 {
98         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
99                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
100                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
101 }
102
103 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
104                               struct ext4_group_desc *bg)
105 {
106         return le32_to_cpu(bg->bg_inode_table_lo) |
107                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
108                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
109 }
110
111 __u32 ext4_free_blks_count(struct super_block *sb,
112                               struct ext4_group_desc *bg)
113 {
114         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
115                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
116                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
117 }
118
119 __u32 ext4_free_inodes_count(struct super_block *sb,
120                               struct ext4_group_desc *bg)
121 {
122         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
123                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
124                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
125 }
126
127 __u32 ext4_used_dirs_count(struct super_block *sb,
128                               struct ext4_group_desc *bg)
129 {
130         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
131                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
132                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
133 }
134
135 __u32 ext4_itable_unused_count(struct super_block *sb,
136                               struct ext4_group_desc *bg)
137 {
138         return le16_to_cpu(bg->bg_itable_unused_lo) |
139                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
140                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
141 }
142
143 void ext4_block_bitmap_set(struct super_block *sb,
144                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
145 {
146         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
147         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
148                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
149 }
150
151 void ext4_inode_bitmap_set(struct super_block *sb,
152                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
153 {
154         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
155         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
156                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
157 }
158
159 void ext4_inode_table_set(struct super_block *sb,
160                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
161 {
162         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
163         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
164                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
165 }
166
167 void ext4_free_blks_set(struct super_block *sb,
168                           struct ext4_group_desc *bg, __u32 count)
169 {
170         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
171         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
172                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
173 }
174
175 void ext4_free_inodes_set(struct super_block *sb,
176                           struct ext4_group_desc *bg, __u32 count)
177 {
178         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
179         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
180                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
181 }
182
183 void ext4_used_dirs_set(struct super_block *sb,
184                           struct ext4_group_desc *bg, __u32 count)
185 {
186         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
187         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
188                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
189 }
190
191 void ext4_itable_unused_set(struct super_block *sb,
192                           struct ext4_group_desc *bg, __u32 count)
193 {
194         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
195         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
196                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
197 }
198
199
200 /* Just increment the non-pointer handle value */
201 static handle_t *ext4_get_nojournal(void)
202 {
203         handle_t *handle = current->journal_info;
204         unsigned long ref_cnt = (unsigned long)handle;
205
206         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
207
208         ref_cnt++;
209         handle = (handle_t *)ref_cnt;
210
211         current->journal_info = handle;
212         return handle;
213 }
214
215
216 /* Decrement the non-pointer handle value */
217 static void ext4_put_nojournal(handle_t *handle)
218 {
219         unsigned long ref_cnt = (unsigned long)handle;
220
221         BUG_ON(ref_cnt == 0);
222
223         ref_cnt--;
224         handle = (handle_t *)ref_cnt;
225
226         current->journal_info = handle;
227 }
228
229 /*
230  * Wrappers for jbd2_journal_start/end.
231  *
232  * The only special thing we need to do here is to make sure that all
233  * journal_end calls result in the superblock being marked dirty, so
234  * that sync() will call the filesystem's write_super callback if
235  * appropriate.
236  */
237 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
238 {
239         journal_t *journal;
240
241         if (sb->s_flags & MS_RDONLY)
242                 return ERR_PTR(-EROFS);
243
244         /* Special case here: if the journal has aborted behind our
245          * backs (eg. EIO in the commit thread), then we still need to
246          * take the FS itself readonly cleanly. */
247         journal = EXT4_SB(sb)->s_journal;
248         if (journal) {
249                 if (is_journal_aborted(journal)) {
250                         ext4_abort(sb, __func__, "Detected aborted journal");
251                         return ERR_PTR(-EROFS);
252                 }
253                 return jbd2_journal_start(journal, nblocks);
254         }
255         return ext4_get_nojournal();
256 }
257
258 /*
259  * The only special thing we need to do here is to make sure that all
260  * jbd2_journal_stop calls result in the superblock being marked dirty, so
261  * that sync() will call the filesystem's write_super callback if
262  * appropriate.
263  */
264 int __ext4_journal_stop(const char *where, handle_t *handle)
265 {
266         struct super_block *sb;
267         int err;
268         int rc;
269
270         if (!ext4_handle_valid(handle)) {
271                 ext4_put_nojournal(handle);
272                 return 0;
273         }
274         sb = handle->h_transaction->t_journal->j_private;
275         err = handle->h_err;
276         rc = jbd2_journal_stop(handle);
277
278         if (!err)
279                 err = rc;
280         if (err)
281                 __ext4_std_error(sb, where, err);
282         return err;
283 }
284
285 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
286                 struct buffer_head *bh, handle_t *handle, int err)
287 {
288         char nbuf[16];
289         const char *errstr = ext4_decode_error(NULL, err, nbuf);
290
291         BUG_ON(!ext4_handle_valid(handle));
292
293         if (bh)
294                 BUFFER_TRACE(bh, "abort");
295
296         if (!handle->h_err)
297                 handle->h_err = err;
298
299         if (is_handle_aborted(handle))
300                 return;
301
302         printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
303                caller, errstr, err_fn);
304
305         jbd2_journal_abort_handle(handle);
306 }
307
308 /* Deal with the reporting of failure conditions on a filesystem such as
309  * inconsistencies detected or read IO failures.
310  *
311  * On ext2, we can store the error state of the filesystem in the
312  * superblock.  That is not possible on ext4, because we may have other
313  * write ordering constraints on the superblock which prevent us from
314  * writing it out straight away; and given that the journal is about to
315  * be aborted, we can't rely on the current, or future, transactions to
316  * write out the superblock safely.
317  *
318  * We'll just use the jbd2_journal_abort() error code to record an error in
319  * the journal instead.  On recovery, the journal will complain about
320  * that error until we've noted it down and cleared it.
321  */
322
323 static void ext4_handle_error(struct super_block *sb)
324 {
325         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
326
327         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
328         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
329
330         if (sb->s_flags & MS_RDONLY)
331                 return;
332
333         if (!test_opt(sb, ERRORS_CONT)) {
334                 journal_t *journal = EXT4_SB(sb)->s_journal;
335
336                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
337                 if (journal)
338                         jbd2_journal_abort(journal, -EIO);
339         }
340         if (test_opt(sb, ERRORS_RO)) {
341                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
342                 sb->s_flags |= MS_RDONLY;
343         }
344         ext4_commit_super(sb, 1);
345         if (test_opt(sb, ERRORS_PANIC))
346                 panic("EXT4-fs (device %s): panic forced after error\n",
347                         sb->s_id);
348 }
349
350 void __ext4_error(struct super_block *sb, const char *function,
351                 const char *fmt, ...)
352 {
353         va_list args;
354
355         va_start(args, fmt);
356         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
357         vprintk(fmt, args);
358         printk("\n");
359         va_end(args);
360
361         ext4_handle_error(sb);
362 }
363
364 void ext4_error_inode(const char *function, struct inode *inode,
365                       const char *fmt, ...)
366 {
367         va_list args;
368
369         va_start(args, fmt);
370         printk(KERN_CRIT "EXT4-fs error (device %s): %s: inode #%lu: (comm %s) ",
371                inode->i_sb->s_id, function, inode->i_ino, current->comm);
372         vprintk(fmt, args);
373         printk("\n");
374         va_end(args);
375
376         ext4_handle_error(inode->i_sb);
377 }
378
379 void ext4_error_file(const char *function, struct file *file,
380                      const char *fmt, ...)
381 {
382         va_list args;
383         struct inode *inode = file->f_dentry->d_inode;
384         char pathname[80], *path;
385
386         va_start(args, fmt);
387         path = d_path(&(file->f_path), pathname, sizeof(pathname));
388         if (!path)
389                 path = "(unknown)";
390         printk(KERN_CRIT
391                "EXT4-fs error (device %s): %s: inode #%lu (comm %s path %s): ",
392                inode->i_sb->s_id, function, inode->i_ino, current->comm, path);
393         vprintk(fmt, args);
394         printk("\n");
395         va_end(args);
396
397         ext4_handle_error(inode->i_sb);
398 }
399
400 static const char *ext4_decode_error(struct super_block *sb, int errno,
401                                      char nbuf[16])
402 {
403         char *errstr = NULL;
404
405         switch (errno) {
406         case -EIO:
407                 errstr = "IO failure";
408                 break;
409         case -ENOMEM:
410                 errstr = "Out of memory";
411                 break;
412         case -EROFS:
413                 if (!sb || (EXT4_SB(sb)->s_journal &&
414                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
415                         errstr = "Journal has aborted";
416                 else
417                         errstr = "Readonly filesystem";
418                 break;
419         default:
420                 /* If the caller passed in an extra buffer for unknown
421                  * errors, textualise them now.  Else we just return
422                  * NULL. */
423                 if (nbuf) {
424                         /* Check for truncated error codes... */
425                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
426                                 errstr = nbuf;
427                 }
428                 break;
429         }
430
431         return errstr;
432 }
433
434 /* __ext4_std_error decodes expected errors from journaling functions
435  * automatically and invokes the appropriate error response.  */
436
437 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
438 {
439         char nbuf[16];
440         const char *errstr;
441
442         /* Special case: if the error is EROFS, and we're not already
443          * inside a transaction, then there's really no point in logging
444          * an error. */
445         if (errno == -EROFS && journal_current_handle() == NULL &&
446             (sb->s_flags & MS_RDONLY))
447                 return;
448
449         errstr = ext4_decode_error(sb, errno, nbuf);
450         printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
451                sb->s_id, function, errstr);
452
453         ext4_handle_error(sb);
454 }
455
456 /*
457  * ext4_abort is a much stronger failure handler than ext4_error.  The
458  * abort function may be used to deal with unrecoverable failures such
459  * as journal IO errors or ENOMEM at a critical moment in log management.
460  *
461  * We unconditionally force the filesystem into an ABORT|READONLY state,
462  * unless the error response on the fs has been set to panic in which
463  * case we take the easy way out and panic immediately.
464  */
465
466 void ext4_abort(struct super_block *sb, const char *function,
467                 const char *fmt, ...)
468 {
469         va_list args;
470
471         va_start(args, fmt);
472         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
473         vprintk(fmt, args);
474         printk("\n");
475         va_end(args);
476
477         if (test_opt(sb, ERRORS_PANIC))
478                 panic("EXT4-fs panic from previous error\n");
479
480         if (sb->s_flags & MS_RDONLY)
481                 return;
482
483         ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
484         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
485         sb->s_flags |= MS_RDONLY;
486         EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
487         if (EXT4_SB(sb)->s_journal)
488                 jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
489 }
490
491 void ext4_msg (struct super_block * sb, const char *prefix,
492                    const char *fmt, ...)
493 {
494         va_list args;
495
496         va_start(args, fmt);
497         printk("%sEXT4-fs (%s): ", prefix, sb->s_id);
498         vprintk(fmt, args);
499         printk("\n");
500         va_end(args);
501 }
502
503 void __ext4_warning(struct super_block *sb, const char *function,
504                   const char *fmt, ...)
505 {
506         va_list args;
507
508         va_start(args, fmt);
509         printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
510                sb->s_id, function);
511         vprintk(fmt, args);
512         printk("\n");
513         va_end(args);
514 }
515
516 void ext4_grp_locked_error(struct super_block *sb, ext4_group_t grp,
517                            const char *function, const char *fmt, ...)
518 __releases(bitlock)
519 __acquires(bitlock)
520 {
521         va_list args;
522         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
523
524         va_start(args, fmt);
525         printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
526         vprintk(fmt, args);
527         printk("\n");
528         va_end(args);
529
530         if (test_opt(sb, ERRORS_CONT)) {
531                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
532                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
533                 ext4_commit_super(sb, 0);
534                 return;
535         }
536         ext4_unlock_group(sb, grp);
537         ext4_handle_error(sb);
538         /*
539          * We only get here in the ERRORS_RO case; relocking the group
540          * may be dangerous, but nothing bad will happen since the
541          * filesystem will have already been marked read/only and the
542          * journal has been aborted.  We return 1 as a hint to callers
543          * who might what to use the return value from
544          * ext4_grp_locked_error() to distinguish beween the
545          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
546          * aggressively from the ext4 function in question, with a
547          * more appropriate error code.
548          */
549         ext4_lock_group(sb, grp);
550         return;
551 }
552
553 void ext4_update_dynamic_rev(struct super_block *sb)
554 {
555         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
556
557         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
558                 return;
559
560         ext4_warning(sb,
561                      "updating to rev %d because of new feature flag, "
562                      "running e2fsck is recommended",
563                      EXT4_DYNAMIC_REV);
564
565         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
566         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
567         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
568         /* leave es->s_feature_*compat flags alone */
569         /* es->s_uuid will be set by e2fsck if empty */
570
571         /*
572          * The rest of the superblock fields should be zero, and if not it
573          * means they are likely already in use, so leave them alone.  We
574          * can leave it up to e2fsck to clean up any inconsistencies there.
575          */
576 }
577
578 /*
579  * Open the external journal device
580  */
581 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
582 {
583         struct block_device *bdev;
584         char b[BDEVNAME_SIZE];
585
586         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
587         if (IS_ERR(bdev))
588                 goto fail;
589         return bdev;
590
591 fail:
592         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
593                         __bdevname(dev, b), PTR_ERR(bdev));
594         return NULL;
595 }
596
597 /*
598  * Release the journal device
599  */
600 static int ext4_blkdev_put(struct block_device *bdev)
601 {
602         bd_release(bdev);
603         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
604 }
605
606 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
607 {
608         struct block_device *bdev;
609         int ret = -ENODEV;
610
611         bdev = sbi->journal_bdev;
612         if (bdev) {
613                 ret = ext4_blkdev_put(bdev);
614                 sbi->journal_bdev = NULL;
615         }
616         return ret;
617 }
618
619 static inline struct inode *orphan_list_entry(struct list_head *l)
620 {
621         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
622 }
623
624 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
625 {
626         struct list_head *l;
627
628         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
629                  le32_to_cpu(sbi->s_es->s_last_orphan));
630
631         printk(KERN_ERR "sb_info orphan list:\n");
632         list_for_each(l, &sbi->s_orphan) {
633                 struct inode *inode = orphan_list_entry(l);
634                 printk(KERN_ERR "  "
635                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
636                        inode->i_sb->s_id, inode->i_ino, inode,
637                        inode->i_mode, inode->i_nlink,
638                        NEXT_ORPHAN(inode));
639         }
640 }
641
642 static void ext4_put_super(struct super_block *sb)
643 {
644         struct ext4_sb_info *sbi = EXT4_SB(sb);
645         struct ext4_super_block *es = sbi->s_es;
646         int i, err;
647
648         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
649
650         flush_workqueue(sbi->dio_unwritten_wq);
651         destroy_workqueue(sbi->dio_unwritten_wq);
652
653         lock_super(sb);
654         lock_kernel();
655         if (sb->s_dirt)
656                 ext4_commit_super(sb, 1);
657
658         if (sbi->s_journal) {
659                 err = jbd2_journal_destroy(sbi->s_journal);
660                 sbi->s_journal = NULL;
661                 if (err < 0)
662                         ext4_abort(sb, __func__,
663                                    "Couldn't clean up the journal");
664         }
665
666         ext4_release_system_zone(sb);
667         ext4_mb_release(sb);
668         ext4_ext_release(sb);
669         ext4_xattr_put_super(sb);
670
671         if (!(sb->s_flags & MS_RDONLY)) {
672                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
673                 es->s_state = cpu_to_le16(sbi->s_mount_state);
674                 ext4_commit_super(sb, 1);
675         }
676         if (sbi->s_proc) {
677                 remove_proc_entry(sb->s_id, ext4_proc_root);
678         }
679         kobject_del(&sbi->s_kobj);
680
681         for (i = 0; i < sbi->s_gdb_count; i++)
682                 brelse(sbi->s_group_desc[i]);
683         kfree(sbi->s_group_desc);
684         if (is_vmalloc_addr(sbi->s_flex_groups))
685                 vfree(sbi->s_flex_groups);
686         else
687                 kfree(sbi->s_flex_groups);
688         percpu_counter_destroy(&sbi->s_freeblocks_counter);
689         percpu_counter_destroy(&sbi->s_freeinodes_counter);
690         percpu_counter_destroy(&sbi->s_dirs_counter);
691         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
692         brelse(sbi->s_sbh);
693 #ifdef CONFIG_QUOTA
694         for (i = 0; i < MAXQUOTAS; i++)
695                 kfree(sbi->s_qf_names[i]);
696 #endif
697
698         /* Debugging code just in case the in-memory inode orphan list
699          * isn't empty.  The on-disk one can be non-empty if we've
700          * detected an error and taken the fs readonly, but the
701          * in-memory list had better be clean by this point. */
702         if (!list_empty(&sbi->s_orphan))
703                 dump_orphan_list(sb, sbi);
704         J_ASSERT(list_empty(&sbi->s_orphan));
705
706         invalidate_bdev(sb->s_bdev);
707         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
708                 /*
709                  * Invalidate the journal device's buffers.  We don't want them
710                  * floating about in memory - the physical journal device may
711                  * hotswapped, and it breaks the `ro-after' testing code.
712                  */
713                 sync_blockdev(sbi->journal_bdev);
714                 invalidate_bdev(sbi->journal_bdev);
715                 ext4_blkdev_remove(sbi);
716         }
717         sb->s_fs_info = NULL;
718         /*
719          * Now that we are completely done shutting down the
720          * superblock, we need to actually destroy the kobject.
721          */
722         unlock_kernel();
723         unlock_super(sb);
724         kobject_put(&sbi->s_kobj);
725         wait_for_completion(&sbi->s_kobj_unregister);
726         kfree(sbi->s_blockgroup_lock);
727         kfree(sbi);
728 }
729
730 static struct kmem_cache *ext4_inode_cachep;
731
732 /*
733  * Called inside transaction, so use GFP_NOFS
734  */
735 static struct inode *ext4_alloc_inode(struct super_block *sb)
736 {
737         struct ext4_inode_info *ei;
738
739         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
740         if (!ei)
741                 return NULL;
742
743         ei->vfs_inode.i_version = 1;
744         ei->vfs_inode.i_data.writeback_index = 0;
745         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
746         INIT_LIST_HEAD(&ei->i_prealloc_list);
747         spin_lock_init(&ei->i_prealloc_lock);
748         /*
749          * Note:  We can be called before EXT4_SB(sb)->s_journal is set,
750          * therefore it can be null here.  Don't check it, just initialize
751          * jinode.
752          */
753         jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
754         ei->i_reserved_data_blocks = 0;
755         ei->i_reserved_meta_blocks = 0;
756         ei->i_allocated_meta_blocks = 0;
757         ei->i_da_metadata_calc_len = 0;
758         ei->i_delalloc_reserved_flag = 0;
759         spin_lock_init(&(ei->i_block_reservation_lock));
760 #ifdef CONFIG_QUOTA
761         ei->i_reserved_quota = 0;
762 #endif
763         INIT_LIST_HEAD(&ei->i_completed_io_list);
764         spin_lock_init(&ei->i_completed_io_lock);
765         ei->cur_aio_dio = NULL;
766         ei->i_sync_tid = 0;
767         ei->i_datasync_tid = 0;
768
769         return &ei->vfs_inode;
770 }
771
772 static void ext4_destroy_inode(struct inode *inode)
773 {
774         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
775                 ext4_msg(inode->i_sb, KERN_ERR,
776                          "Inode %lu (%p): orphan list check failed!",
777                          inode->i_ino, EXT4_I(inode));
778                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
779                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
780                                 true);
781                 dump_stack();
782         }
783         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
784 }
785
786 static void init_once(void *foo)
787 {
788         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
789
790         INIT_LIST_HEAD(&ei->i_orphan);
791 #ifdef CONFIG_EXT4_FS_XATTR
792         init_rwsem(&ei->xattr_sem);
793 #endif
794         init_rwsem(&ei->i_data_sem);
795         inode_init_once(&ei->vfs_inode);
796 }
797
798 static int init_inodecache(void)
799 {
800         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
801                                              sizeof(struct ext4_inode_info),
802                                              0, (SLAB_RECLAIM_ACCOUNT|
803                                                 SLAB_MEM_SPREAD),
804                                              init_once);
805         if (ext4_inode_cachep == NULL)
806                 return -ENOMEM;
807         return 0;
808 }
809
810 static void destroy_inodecache(void)
811 {
812         kmem_cache_destroy(ext4_inode_cachep);
813 }
814
815 static void ext4_clear_inode(struct inode *inode)
816 {
817         dquot_drop(inode);
818         ext4_discard_preallocations(inode);
819         if (EXT4_JOURNAL(inode))
820                 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
821                                        &EXT4_I(inode)->jinode);
822 }
823
824 static inline void ext4_show_quota_options(struct seq_file *seq,
825                                            struct super_block *sb)
826 {
827 #if defined(CONFIG_QUOTA)
828         struct ext4_sb_info *sbi = EXT4_SB(sb);
829
830         if (sbi->s_jquota_fmt) {
831                 char *fmtname = "";
832
833                 switch (sbi->s_jquota_fmt) {
834                 case QFMT_VFS_OLD:
835                         fmtname = "vfsold";
836                         break;
837                 case QFMT_VFS_V0:
838                         fmtname = "vfsv0";
839                         break;
840                 case QFMT_VFS_V1:
841                         fmtname = "vfsv1";
842                         break;
843                 }
844                 seq_printf(seq, ",jqfmt=%s", fmtname);
845         }
846
847         if (sbi->s_qf_names[USRQUOTA])
848                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
849
850         if (sbi->s_qf_names[GRPQUOTA])
851                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
852
853         if (test_opt(sb, USRQUOTA))
854                 seq_puts(seq, ",usrquota");
855
856         if (test_opt(sb, GRPQUOTA))
857                 seq_puts(seq, ",grpquota");
858 #endif
859 }
860
861 /*
862  * Show an option if
863  *  - it's set to a non-default value OR
864  *  - if the per-sb default is different from the global default
865  */
866 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
867 {
868         int def_errors;
869         unsigned long def_mount_opts;
870         struct super_block *sb = vfs->mnt_sb;
871         struct ext4_sb_info *sbi = EXT4_SB(sb);
872         struct ext4_super_block *es = sbi->s_es;
873
874         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
875         def_errors     = le16_to_cpu(es->s_errors);
876
877         if (sbi->s_sb_block != 1)
878                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
879         if (test_opt(sb, MINIX_DF))
880                 seq_puts(seq, ",minixdf");
881         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
882                 seq_puts(seq, ",grpid");
883         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
884                 seq_puts(seq, ",nogrpid");
885         if (sbi->s_resuid != EXT4_DEF_RESUID ||
886             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
887                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
888         }
889         if (sbi->s_resgid != EXT4_DEF_RESGID ||
890             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
891                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
892         }
893         if (test_opt(sb, ERRORS_RO)) {
894                 if (def_errors == EXT4_ERRORS_PANIC ||
895                     def_errors == EXT4_ERRORS_CONTINUE) {
896                         seq_puts(seq, ",errors=remount-ro");
897                 }
898         }
899         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
900                 seq_puts(seq, ",errors=continue");
901         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
902                 seq_puts(seq, ",errors=panic");
903         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
904                 seq_puts(seq, ",nouid32");
905         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
906                 seq_puts(seq, ",debug");
907         if (test_opt(sb, OLDALLOC))
908                 seq_puts(seq, ",oldalloc");
909 #ifdef CONFIG_EXT4_FS_XATTR
910         if (test_opt(sb, XATTR_USER) &&
911                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
912                 seq_puts(seq, ",user_xattr");
913         if (!test_opt(sb, XATTR_USER) &&
914             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
915                 seq_puts(seq, ",nouser_xattr");
916         }
917 #endif
918 #ifdef CONFIG_EXT4_FS_POSIX_ACL
919         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
920                 seq_puts(seq, ",acl");
921         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
922                 seq_puts(seq, ",noacl");
923 #endif
924         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
925                 seq_printf(seq, ",commit=%u",
926                            (unsigned) (sbi->s_commit_interval / HZ));
927         }
928         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
929                 seq_printf(seq, ",min_batch_time=%u",
930                            (unsigned) sbi->s_min_batch_time);
931         }
932         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
933                 seq_printf(seq, ",max_batch_time=%u",
934                            (unsigned) sbi->s_min_batch_time);
935         }
936
937         /*
938          * We're changing the default of barrier mount option, so
939          * let's always display its mount state so it's clear what its
940          * status is.
941          */
942         seq_puts(seq, ",barrier=");
943         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
944         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
945                 seq_puts(seq, ",journal_async_commit");
946         if (test_opt(sb, NOBH))
947                 seq_puts(seq, ",nobh");
948         if (test_opt(sb, I_VERSION))
949                 seq_puts(seq, ",i_version");
950         if (!test_opt(sb, DELALLOC))
951                 seq_puts(seq, ",nodelalloc");
952
953
954         if (sbi->s_stripe)
955                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
956         /*
957          * journal mode get enabled in different ways
958          * So just print the value even if we didn't specify it
959          */
960         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
961                 seq_puts(seq, ",data=journal");
962         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
963                 seq_puts(seq, ",data=ordered");
964         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
965                 seq_puts(seq, ",data=writeback");
966
967         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
968                 seq_printf(seq, ",inode_readahead_blks=%u",
969                            sbi->s_inode_readahead_blks);
970
971         if (test_opt(sb, DATA_ERR_ABORT))
972                 seq_puts(seq, ",data_err=abort");
973
974         if (test_opt(sb, NO_AUTO_DA_ALLOC))
975                 seq_puts(seq, ",noauto_da_alloc");
976
977         if (test_opt(sb, DISCARD))
978                 seq_puts(seq, ",discard");
979
980         if (test_opt(sb, NOLOAD))
981                 seq_puts(seq, ",norecovery");
982
983         if (test_opt(sb, DIOREAD_NOLOCK))
984                 seq_puts(seq, ",dioread_nolock");
985
986         ext4_show_quota_options(seq, sb);
987
988         return 0;
989 }
990
991 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
992                                         u64 ino, u32 generation)
993 {
994         struct inode *inode;
995
996         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
997                 return ERR_PTR(-ESTALE);
998         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
999                 return ERR_PTR(-ESTALE);
1000
1001         /* iget isn't really right if the inode is currently unallocated!!
1002          *
1003          * ext4_read_inode will return a bad_inode if the inode had been
1004          * deleted, so we should be safe.
1005          *
1006          * Currently we don't know the generation for parent directory, so
1007          * a generation of 0 means "accept any"
1008          */
1009         inode = ext4_iget(sb, ino);
1010         if (IS_ERR(inode))
1011                 return ERR_CAST(inode);
1012         if (generation && inode->i_generation != generation) {
1013                 iput(inode);
1014                 return ERR_PTR(-ESTALE);
1015         }
1016
1017         return inode;
1018 }
1019
1020 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1021                                         int fh_len, int fh_type)
1022 {
1023         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1024                                     ext4_nfs_get_inode);
1025 }
1026
1027 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1028                                         int fh_len, int fh_type)
1029 {
1030         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1031                                     ext4_nfs_get_inode);
1032 }
1033
1034 /*
1035  * Try to release metadata pages (indirect blocks, directories) which are
1036  * mapped via the block device.  Since these pages could have journal heads
1037  * which would prevent try_to_free_buffers() from freeing them, we must use
1038  * jbd2 layer's try_to_free_buffers() function to release them.
1039  */
1040 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1041                                  gfp_t wait)
1042 {
1043         journal_t *journal = EXT4_SB(sb)->s_journal;
1044
1045         WARN_ON(PageChecked(page));
1046         if (!page_has_buffers(page))
1047                 return 0;
1048         if (journal)
1049                 return jbd2_journal_try_to_free_buffers(journal, page,
1050                                                         wait & ~__GFP_WAIT);
1051         return try_to_free_buffers(page);
1052 }
1053
1054 #ifdef CONFIG_QUOTA
1055 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1056 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1057
1058 static int ext4_write_dquot(struct dquot *dquot);
1059 static int ext4_acquire_dquot(struct dquot *dquot);
1060 static int ext4_release_dquot(struct dquot *dquot);
1061 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1062 static int ext4_write_info(struct super_block *sb, int type);
1063 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1064                                 char *path);
1065 static int ext4_quota_on_mount(struct super_block *sb, int type);
1066 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1067                                size_t len, loff_t off);
1068 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1069                                 const char *data, size_t len, loff_t off);
1070
1071 static const struct dquot_operations ext4_quota_operations = {
1072 #ifdef CONFIG_QUOTA
1073         .get_reserved_space = ext4_get_reserved_space,
1074 #endif
1075         .write_dquot    = ext4_write_dquot,
1076         .acquire_dquot  = ext4_acquire_dquot,
1077         .release_dquot  = ext4_release_dquot,
1078         .mark_dirty     = ext4_mark_dquot_dirty,
1079         .write_info     = ext4_write_info,
1080         .alloc_dquot    = dquot_alloc,
1081         .destroy_dquot  = dquot_destroy,
1082 };
1083
1084 static const struct quotactl_ops ext4_qctl_operations = {
1085         .quota_on       = ext4_quota_on,
1086         .quota_off      = vfs_quota_off,
1087         .quota_sync     = vfs_quota_sync,
1088         .get_info       = vfs_get_dqinfo,
1089         .set_info       = vfs_set_dqinfo,
1090         .get_dqblk      = vfs_get_dqblk,
1091         .set_dqblk      = vfs_set_dqblk
1092 };
1093 #endif
1094
1095 static const struct super_operations ext4_sops = {
1096         .alloc_inode    = ext4_alloc_inode,
1097         .destroy_inode  = ext4_destroy_inode,
1098         .write_inode    = ext4_write_inode,
1099         .dirty_inode    = ext4_dirty_inode,
1100         .delete_inode   = ext4_delete_inode,
1101         .put_super      = ext4_put_super,
1102         .sync_fs        = ext4_sync_fs,
1103         .freeze_fs      = ext4_freeze,
1104         .unfreeze_fs    = ext4_unfreeze,
1105         .statfs         = ext4_statfs,
1106         .remount_fs     = ext4_remount,
1107         .clear_inode    = ext4_clear_inode,
1108         .show_options   = ext4_show_options,
1109 #ifdef CONFIG_QUOTA
1110         .quota_read     = ext4_quota_read,
1111         .quota_write    = ext4_quota_write,
1112 #endif
1113         .bdev_try_to_free_page = bdev_try_to_free_page,
1114 };
1115
1116 static const struct super_operations ext4_nojournal_sops = {
1117         .alloc_inode    = ext4_alloc_inode,
1118         .destroy_inode  = ext4_destroy_inode,
1119         .write_inode    = ext4_write_inode,
1120         .dirty_inode    = ext4_dirty_inode,
1121         .delete_inode   = ext4_delete_inode,
1122         .write_super    = ext4_write_super,
1123         .put_super      = ext4_put_super,
1124         .statfs         = ext4_statfs,
1125         .remount_fs     = ext4_remount,
1126         .clear_inode    = ext4_clear_inode,
1127         .show_options   = ext4_show_options,
1128 #ifdef CONFIG_QUOTA
1129         .quota_read     = ext4_quota_read,
1130         .quota_write    = ext4_quota_write,
1131 #endif
1132         .bdev_try_to_free_page = bdev_try_to_free_page,
1133 };
1134
1135 static const struct export_operations ext4_export_ops = {
1136         .fh_to_dentry = ext4_fh_to_dentry,
1137         .fh_to_parent = ext4_fh_to_parent,
1138         .get_parent = ext4_get_parent,
1139 };
1140
1141 enum {
1142         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1143         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1144         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1145         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1146         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1147         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1148         Opt_journal_update, Opt_journal_dev,
1149         Opt_journal_checksum, Opt_journal_async_commit,
1150         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1151         Opt_data_err_abort, Opt_data_err_ignore,
1152         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1153         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1154         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1155         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1156         Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1157         Opt_block_validity, Opt_noblock_validity,
1158         Opt_inode_readahead_blks, Opt_journal_ioprio,
1159         Opt_dioread_nolock, Opt_dioread_lock,
1160         Opt_discard, Opt_nodiscard,
1161 };
1162
1163 static const match_table_t tokens = {
1164         {Opt_bsd_df, "bsddf"},
1165         {Opt_minix_df, "minixdf"},
1166         {Opt_grpid, "grpid"},
1167         {Opt_grpid, "bsdgroups"},
1168         {Opt_nogrpid, "nogrpid"},
1169         {Opt_nogrpid, "sysvgroups"},
1170         {Opt_resgid, "resgid=%u"},
1171         {Opt_resuid, "resuid=%u"},
1172         {Opt_sb, "sb=%u"},
1173         {Opt_err_cont, "errors=continue"},
1174         {Opt_err_panic, "errors=panic"},
1175         {Opt_err_ro, "errors=remount-ro"},
1176         {Opt_nouid32, "nouid32"},
1177         {Opt_debug, "debug"},
1178         {Opt_oldalloc, "oldalloc"},
1179         {Opt_orlov, "orlov"},
1180         {Opt_user_xattr, "user_xattr"},
1181         {Opt_nouser_xattr, "nouser_xattr"},
1182         {Opt_acl, "acl"},
1183         {Opt_noacl, "noacl"},
1184         {Opt_noload, "noload"},
1185         {Opt_noload, "norecovery"},
1186         {Opt_nobh, "nobh"},
1187         {Opt_bh, "bh"},
1188         {Opt_commit, "commit=%u"},
1189         {Opt_min_batch_time, "min_batch_time=%u"},
1190         {Opt_max_batch_time, "max_batch_time=%u"},
1191         {Opt_journal_update, "journal=update"},
1192         {Opt_journal_dev, "journal_dev=%u"},
1193         {Opt_journal_checksum, "journal_checksum"},
1194         {Opt_journal_async_commit, "journal_async_commit"},
1195         {Opt_abort, "abort"},
1196         {Opt_data_journal, "data=journal"},
1197         {Opt_data_ordered, "data=ordered"},
1198         {Opt_data_writeback, "data=writeback"},
1199         {Opt_data_err_abort, "data_err=abort"},
1200         {Opt_data_err_ignore, "data_err=ignore"},
1201         {Opt_offusrjquota, "usrjquota="},
1202         {Opt_usrjquota, "usrjquota=%s"},
1203         {Opt_offgrpjquota, "grpjquota="},
1204         {Opt_grpjquota, "grpjquota=%s"},
1205         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1206         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1207         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1208         {Opt_grpquota, "grpquota"},
1209         {Opt_noquota, "noquota"},
1210         {Opt_quota, "quota"},
1211         {Opt_usrquota, "usrquota"},
1212         {Opt_barrier, "barrier=%u"},
1213         {Opt_barrier, "barrier"},
1214         {Opt_nobarrier, "nobarrier"},
1215         {Opt_i_version, "i_version"},
1216         {Opt_stripe, "stripe=%u"},
1217         {Opt_resize, "resize"},
1218         {Opt_delalloc, "delalloc"},
1219         {Opt_nodelalloc, "nodelalloc"},
1220         {Opt_block_validity, "block_validity"},
1221         {Opt_noblock_validity, "noblock_validity"},
1222         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1223         {Opt_journal_ioprio, "journal_ioprio=%u"},
1224         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1225         {Opt_auto_da_alloc, "auto_da_alloc"},
1226         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1227         {Opt_dioread_nolock, "dioread_nolock"},
1228         {Opt_dioread_lock, "dioread_lock"},
1229         {Opt_discard, "discard"},
1230         {Opt_nodiscard, "nodiscard"},
1231         {Opt_err, NULL},
1232 };
1233
1234 static ext4_fsblk_t get_sb_block(void **data)
1235 {
1236         ext4_fsblk_t    sb_block;
1237         char            *options = (char *) *data;
1238
1239         if (!options || strncmp(options, "sb=", 3) != 0)
1240                 return 1;       /* Default location */
1241
1242         options += 3;
1243         /* TODO: use simple_strtoll with >32bit ext4 */
1244         sb_block = simple_strtoul(options, &options, 0);
1245         if (*options && *options != ',') {
1246                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1247                        (char *) *data);
1248                 return 1;
1249         }
1250         if (*options == ',')
1251                 options++;
1252         *data = (void *) options;
1253
1254         return sb_block;
1255 }
1256
1257 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1258 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1259         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1260
1261 #ifdef CONFIG_QUOTA
1262 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1263 {
1264         struct ext4_sb_info *sbi = EXT4_SB(sb);
1265         char *qname;
1266
1267         if (sb_any_quota_loaded(sb) &&
1268                 !sbi->s_qf_names[qtype]) {
1269                 ext4_msg(sb, KERN_ERR,
1270                         "Cannot change journaled "
1271                         "quota options when quota turned on");
1272                 return 0;
1273         }
1274         qname = match_strdup(args);
1275         if (!qname) {
1276                 ext4_msg(sb, KERN_ERR,
1277                         "Not enough memory for storing quotafile name");
1278                 return 0;
1279         }
1280         if (sbi->s_qf_names[qtype] &&
1281                 strcmp(sbi->s_qf_names[qtype], qname)) {
1282                 ext4_msg(sb, KERN_ERR,
1283                         "%s quota file already specified", QTYPE2NAME(qtype));
1284                 kfree(qname);
1285                 return 0;
1286         }
1287         sbi->s_qf_names[qtype] = qname;
1288         if (strchr(sbi->s_qf_names[qtype], '/')) {
1289                 ext4_msg(sb, KERN_ERR,
1290                         "quotafile must be on filesystem root");
1291                 kfree(sbi->s_qf_names[qtype]);
1292                 sbi->s_qf_names[qtype] = NULL;
1293                 return 0;
1294         }
1295         set_opt(sbi->s_mount_opt, QUOTA);
1296         return 1;
1297 }
1298
1299 static int clear_qf_name(struct super_block *sb, int qtype)
1300 {
1301
1302         struct ext4_sb_info *sbi = EXT4_SB(sb);
1303
1304         if (sb_any_quota_loaded(sb) &&
1305                 sbi->s_qf_names[qtype]) {
1306                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1307                         " when quota turned on");
1308                 return 0;
1309         }
1310         /*
1311          * The space will be released later when all options are confirmed
1312          * to be correct
1313          */
1314         sbi->s_qf_names[qtype] = NULL;
1315         return 1;
1316 }
1317 #endif
1318
1319 static int parse_options(char *options, struct super_block *sb,
1320                          unsigned long *journal_devnum,
1321                          unsigned int *journal_ioprio,
1322                          ext4_fsblk_t *n_blocks_count, int is_remount)
1323 {
1324         struct ext4_sb_info *sbi = EXT4_SB(sb);
1325         char *p;
1326         substring_t args[MAX_OPT_ARGS];
1327         int data_opt = 0;
1328         int option;
1329 #ifdef CONFIG_QUOTA
1330         int qfmt;
1331 #endif
1332
1333         if (!options)
1334                 return 1;
1335
1336         while ((p = strsep(&options, ",")) != NULL) {
1337                 int token;
1338                 if (!*p)
1339                         continue;
1340
1341                 /*
1342                  * Initialize args struct so we know whether arg was
1343                  * found; some options take optional arguments.
1344                  */
1345                 args[0].to = args[0].from = 0;
1346                 token = match_token(p, tokens, args);
1347                 switch (token) {
1348                 case Opt_bsd_df:
1349                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1350                         clear_opt(sbi->s_mount_opt, MINIX_DF);
1351                         break;
1352                 case Opt_minix_df:
1353                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1354                         set_opt(sbi->s_mount_opt, MINIX_DF);
1355
1356                         break;
1357                 case Opt_grpid:
1358                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1359                         set_opt(sbi->s_mount_opt, GRPID);
1360
1361                         break;
1362                 case Opt_nogrpid:
1363                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1364                         clear_opt(sbi->s_mount_opt, GRPID);
1365
1366                         break;
1367                 case Opt_resuid:
1368                         if (match_int(&args[0], &option))
1369                                 return 0;
1370                         sbi->s_resuid = option;
1371                         break;
1372                 case Opt_resgid:
1373                         if (match_int(&args[0], &option))
1374                                 return 0;
1375                         sbi->s_resgid = option;
1376                         break;
1377                 case Opt_sb:
1378                         /* handled by get_sb_block() instead of here */
1379                         /* *sb_block = match_int(&args[0]); */
1380                         break;
1381                 case Opt_err_panic:
1382                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1383                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1384                         set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1385                         break;
1386                 case Opt_err_ro:
1387                         clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1388                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1389                         set_opt(sbi->s_mount_opt, ERRORS_RO);
1390                         break;
1391                 case Opt_err_cont:
1392                         clear_opt(sbi->s_mount_opt, ERRORS_RO);
1393                         clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1394                         set_opt(sbi->s_mount_opt, ERRORS_CONT);
1395                         break;
1396                 case Opt_nouid32:
1397                         set_opt(sbi->s_mount_opt, NO_UID32);
1398                         break;
1399                 case Opt_debug:
1400                         set_opt(sbi->s_mount_opt, DEBUG);
1401                         break;
1402                 case Opt_oldalloc:
1403                         set_opt(sbi->s_mount_opt, OLDALLOC);
1404                         break;
1405                 case Opt_orlov:
1406                         clear_opt(sbi->s_mount_opt, OLDALLOC);
1407                         break;
1408 #ifdef CONFIG_EXT4_FS_XATTR
1409                 case Opt_user_xattr:
1410                         set_opt(sbi->s_mount_opt, XATTR_USER);
1411                         break;
1412                 case Opt_nouser_xattr:
1413                         clear_opt(sbi->s_mount_opt, XATTR_USER);
1414                         break;
1415 #else
1416                 case Opt_user_xattr:
1417                 case Opt_nouser_xattr:
1418                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1419                         break;
1420 #endif
1421 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1422                 case Opt_acl:
1423                         set_opt(sbi->s_mount_opt, POSIX_ACL);
1424                         break;
1425                 case Opt_noacl:
1426                         clear_opt(sbi->s_mount_opt, POSIX_ACL);
1427                         break;
1428 #else
1429                 case Opt_acl:
1430                 case Opt_noacl:
1431                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1432                         break;
1433 #endif
1434                 case Opt_journal_update:
1435                         /* @@@ FIXME */
1436                         /* Eventually we will want to be able to create
1437                            a journal file here.  For now, only allow the
1438                            user to specify an existing inode to be the
1439                            journal file. */
1440                         if (is_remount) {
1441                                 ext4_msg(sb, KERN_ERR,
1442                                          "Cannot specify journal on remount");
1443                                 return 0;
1444                         }
1445                         set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1446                         break;
1447                 case Opt_journal_dev:
1448                         if (is_remount) {
1449                                 ext4_msg(sb, KERN_ERR,
1450                                         "Cannot specify journal on remount");
1451                                 return 0;
1452                         }
1453                         if (match_int(&args[0], &option))
1454                                 return 0;
1455                         *journal_devnum = option;
1456                         break;
1457                 case Opt_journal_checksum:
1458                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1459                         break;
1460                 case Opt_journal_async_commit:
1461                         set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1462                         set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1463                         break;
1464                 case Opt_noload:
1465                         set_opt(sbi->s_mount_opt, NOLOAD);
1466                         break;
1467                 case Opt_commit:
1468                         if (match_int(&args[0], &option))
1469                                 return 0;
1470                         if (option < 0)
1471                                 return 0;
1472                         if (option == 0)
1473                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1474                         sbi->s_commit_interval = HZ * option;
1475                         break;
1476                 case Opt_max_batch_time:
1477                         if (match_int(&args[0], &option))
1478                                 return 0;
1479                         if (option < 0)
1480                                 return 0;
1481                         if (option == 0)
1482                                 option = EXT4_DEF_MAX_BATCH_TIME;
1483                         sbi->s_max_batch_time = option;
1484                         break;
1485                 case Opt_min_batch_time:
1486                         if (match_int(&args[0], &option))
1487                                 return 0;
1488                         if (option < 0)
1489                                 return 0;
1490                         sbi->s_min_batch_time = option;
1491                         break;
1492                 case Opt_data_journal:
1493                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1494                         goto datacheck;
1495                 case Opt_data_ordered:
1496                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1497                         goto datacheck;
1498                 case Opt_data_writeback:
1499                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1500                 datacheck:
1501                         if (is_remount) {
1502                                 if (test_opt(sb, DATA_FLAGS) != data_opt) {
1503                                         ext4_msg(sb, KERN_ERR,
1504                                                 "Cannot change data mode on remount");
1505                                         return 0;
1506                                 }
1507                         } else {
1508                                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
1509                                 sbi->s_mount_opt |= data_opt;
1510                         }
1511                         break;
1512                 case Opt_data_err_abort:
1513                         set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1514                         break;
1515                 case Opt_data_err_ignore:
1516                         clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1517                         break;
1518 #ifdef CONFIG_QUOTA
1519                 case Opt_usrjquota:
1520                         if (!set_qf_name(sb, USRQUOTA, &args[0]))
1521                                 return 0;
1522                         break;
1523                 case Opt_grpjquota:
1524                         if (!set_qf_name(sb, GRPQUOTA, &args[0]))
1525                                 return 0;
1526                         break;
1527                 case Opt_offusrjquota:
1528                         if (!clear_qf_name(sb, USRQUOTA))
1529                                 return 0;
1530                         break;
1531                 case Opt_offgrpjquota:
1532                         if (!clear_qf_name(sb, GRPQUOTA))
1533                                 return 0;
1534                         break;
1535
1536                 case Opt_jqfmt_vfsold:
1537                         qfmt = QFMT_VFS_OLD;
1538                         goto set_qf_format;
1539                 case Opt_jqfmt_vfsv0:
1540                         qfmt = QFMT_VFS_V0;
1541                         goto set_qf_format;
1542                 case Opt_jqfmt_vfsv1:
1543                         qfmt = QFMT_VFS_V1;
1544 set_qf_format:
1545                         if (sb_any_quota_loaded(sb) &&
1546                             sbi->s_jquota_fmt != qfmt) {
1547                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1548                                         "journaled quota options when "
1549                                         "quota turned on");
1550                                 return 0;
1551                         }
1552                         sbi->s_jquota_fmt = qfmt;
1553                         break;
1554                 case Opt_quota:
1555                 case Opt_usrquota:
1556                         set_opt(sbi->s_mount_opt, QUOTA);
1557                         set_opt(sbi->s_mount_opt, USRQUOTA);
1558                         break;
1559                 case Opt_grpquota:
1560                         set_opt(sbi->s_mount_opt, QUOTA);
1561                         set_opt(sbi->s_mount_opt, GRPQUOTA);
1562                         break;
1563                 case Opt_noquota:
1564                         if (sb_any_quota_loaded(sb)) {
1565                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1566                                         "options when quota turned on");
1567                                 return 0;
1568                         }
1569                         clear_opt(sbi->s_mount_opt, QUOTA);
1570                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1571                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1572                         break;
1573 #else
1574                 case Opt_quota:
1575                 case Opt_usrquota:
1576                 case Opt_grpquota:
1577                         ext4_msg(sb, KERN_ERR,
1578                                 "quota options not supported");
1579                         break;
1580                 case Opt_usrjquota:
1581                 case Opt_grpjquota:
1582                 case Opt_offusrjquota:
1583                 case Opt_offgrpjquota:
1584                 case Opt_jqfmt_vfsold:
1585                 case Opt_jqfmt_vfsv0:
1586                 case Opt_jqfmt_vfsv1:
1587                         ext4_msg(sb, KERN_ERR,
1588                                 "journaled quota options not supported");
1589                         break;
1590                 case Opt_noquota:
1591                         break;
1592 #endif
1593                 case Opt_abort:
1594                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1595                         break;
1596                 case Opt_nobarrier:
1597                         clear_opt(sbi->s_mount_opt, BARRIER);
1598                         break;
1599                 case Opt_barrier:
1600                         if (args[0].from) {
1601                                 if (match_int(&args[0], &option))
1602                                         return 0;
1603                         } else
1604                                 option = 1;     /* No argument, default to 1 */
1605                         if (option)
1606                                 set_opt(sbi->s_mount_opt, BARRIER);
1607                         else
1608                                 clear_opt(sbi->s_mount_opt, BARRIER);
1609                         break;
1610                 case Opt_ignore:
1611                         break;
1612                 case Opt_resize:
1613                         if (!is_remount) {
1614                                 ext4_msg(sb, KERN_ERR,
1615                                         "resize option only available "
1616                                         "for remount");
1617                                 return 0;
1618                         }
1619                         if (match_int(&args[0], &option) != 0)
1620                                 return 0;
1621                         *n_blocks_count = option;
1622                         break;
1623                 case Opt_nobh:
1624                         set_opt(sbi->s_mount_opt, NOBH);
1625                         break;
1626                 case Opt_bh:
1627                         clear_opt(sbi->s_mount_opt, NOBH);
1628                         break;
1629                 case Opt_i_version:
1630                         set_opt(sbi->s_mount_opt, I_VERSION);
1631                         sb->s_flags |= MS_I_VERSION;
1632                         break;
1633                 case Opt_nodelalloc:
1634                         clear_opt(sbi->s_mount_opt, DELALLOC);
1635                         break;
1636                 case Opt_stripe:
1637                         if (match_int(&args[0], &option))
1638                                 return 0;
1639                         if (option < 0)
1640                                 return 0;
1641                         sbi->s_stripe = option;
1642                         break;
1643                 case Opt_delalloc:
1644                         set_opt(sbi->s_mount_opt, DELALLOC);
1645                         break;
1646                 case Opt_block_validity:
1647                         set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1648                         break;
1649                 case Opt_noblock_validity:
1650                         clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1651                         break;
1652                 case Opt_inode_readahead_blks:
1653                         if (match_int(&args[0], &option))
1654                                 return 0;
1655                         if (option < 0 || option > (1 << 30))
1656                                 return 0;
1657                         if (!is_power_of_2(option)) {
1658                                 ext4_msg(sb, KERN_ERR,
1659                                          "EXT4-fs: inode_readahead_blks"
1660                                          " must be a power of 2");
1661                                 return 0;
1662                         }
1663                         sbi->s_inode_readahead_blks = option;
1664                         break;
1665                 case Opt_journal_ioprio:
1666                         if (match_int(&args[0], &option))
1667                                 return 0;
1668                         if (option < 0 || option > 7)
1669                                 break;
1670                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1671                                                             option);
1672                         break;
1673                 case Opt_noauto_da_alloc:
1674                         set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1675                         break;
1676                 case Opt_auto_da_alloc:
1677                         if (args[0].from) {
1678                                 if (match_int(&args[0], &option))
1679                                         return 0;
1680                         } else
1681                                 option = 1;     /* No argument, default to 1 */
1682                         if (option)
1683                                 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1684                         else
1685                                 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1686                         break;
1687                 case Opt_discard:
1688                         set_opt(sbi->s_mount_opt, DISCARD);
1689                         break;
1690                 case Opt_nodiscard:
1691                         clear_opt(sbi->s_mount_opt, DISCARD);
1692                         break;
1693                 case Opt_dioread_nolock:
1694                         set_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
1695                         break;
1696                 case Opt_dioread_lock:
1697                         clear_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
1698                         break;
1699                 default:
1700                         ext4_msg(sb, KERN_ERR,
1701                                "Unrecognized mount option \"%s\" "
1702                                "or missing value", p);
1703                         return 0;
1704                 }
1705         }
1706 #ifdef CONFIG_QUOTA
1707         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1708                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1709                         clear_opt(sbi->s_mount_opt, USRQUOTA);
1710
1711                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1712                         clear_opt(sbi->s_mount_opt, GRPQUOTA);
1713
1714                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1715                         ext4_msg(sb, KERN_ERR, "old and new quota "
1716                                         "format mixing");
1717                         return 0;
1718                 }
1719
1720                 if (!sbi->s_jquota_fmt) {
1721                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1722                                         "not specified");
1723                         return 0;
1724                 }
1725         } else {
1726                 if (sbi->s_jquota_fmt) {
1727                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1728                                         "specified with no journaling "
1729                                         "enabled");
1730                         return 0;
1731                 }
1732         }
1733 #endif
1734         return 1;
1735 }
1736
1737 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1738                             int read_only)
1739 {
1740         struct ext4_sb_info *sbi = EXT4_SB(sb);
1741         int res = 0;
1742
1743         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1744                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1745                          "forcing read-only mode");
1746                 res = MS_RDONLY;
1747         }
1748         if (read_only)
1749                 return res;
1750         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1751                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1752                          "running e2fsck is recommended");
1753         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1754                 ext4_msg(sb, KERN_WARNING,
1755                          "warning: mounting fs with errors, "
1756                          "running e2fsck is recommended");
1757         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1758                  le16_to_cpu(es->s_mnt_count) >=
1759                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1760                 ext4_msg(sb, KERN_WARNING,
1761                          "warning: maximal mount count reached, "
1762                          "running e2fsck is recommended");
1763         else if (le32_to_cpu(es->s_checkinterval) &&
1764                 (le32_to_cpu(es->s_lastcheck) +
1765                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1766                 ext4_msg(sb, KERN_WARNING,
1767                          "warning: checktime reached, "
1768                          "running e2fsck is recommended");
1769         if (!sbi->s_journal)
1770                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1771         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1772                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1773         le16_add_cpu(&es->s_mnt_count, 1);
1774         es->s_mtime = cpu_to_le32(get_seconds());
1775         ext4_update_dynamic_rev(sb);
1776         if (sbi->s_journal)
1777                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1778
1779         ext4_commit_super(sb, 1);
1780         if (test_opt(sb, DEBUG))
1781                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1782                                 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1783                         sb->s_blocksize,
1784                         sbi->s_groups_count,
1785                         EXT4_BLOCKS_PER_GROUP(sb),
1786                         EXT4_INODES_PER_GROUP(sb),
1787                         sbi->s_mount_opt);
1788
1789         return res;
1790 }
1791
1792 static int ext4_fill_flex_info(struct super_block *sb)
1793 {
1794         struct ext4_sb_info *sbi = EXT4_SB(sb);
1795         struct ext4_group_desc *gdp = NULL;
1796         ext4_group_t flex_group_count;
1797         ext4_group_t flex_group;
1798         int groups_per_flex = 0;
1799         size_t size;
1800         int i;
1801
1802         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1803         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1804
1805         if (groups_per_flex < 2) {
1806                 sbi->s_log_groups_per_flex = 0;
1807                 return 1;
1808         }
1809
1810         /* We allocate both existing and potentially added groups */
1811         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1812                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1813                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1814         size = flex_group_count * sizeof(struct flex_groups);
1815         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1816         if (sbi->s_flex_groups == NULL) {
1817                 sbi->s_flex_groups = vmalloc(size);
1818                 if (sbi->s_flex_groups)
1819                         memset(sbi->s_flex_groups, 0, size);
1820         }
1821         if (sbi->s_flex_groups == NULL) {
1822                 ext4_msg(sb, KERN_ERR, "not enough memory for "
1823                                 "%u flex groups", flex_group_count);
1824                 goto failed;
1825         }
1826
1827         for (i = 0; i < sbi->s_groups_count; i++) {
1828                 gdp = ext4_get_group_desc(sb, i, NULL);
1829
1830                 flex_group = ext4_flex_group(sbi, i);
1831                 atomic_add(ext4_free_inodes_count(sb, gdp),
1832                            &sbi->s_flex_groups[flex_group].free_inodes);
1833                 atomic_add(ext4_free_blks_count(sb, gdp),
1834                            &sbi->s_flex_groups[flex_group].free_blocks);
1835                 atomic_add(ext4_used_dirs_count(sb, gdp),
1836                            &sbi->s_flex_groups[flex_group].used_dirs);
1837         }
1838
1839         return 1;
1840 failed:
1841         return 0;
1842 }
1843
1844 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1845                             struct ext4_group_desc *gdp)
1846 {
1847         __u16 crc = 0;
1848
1849         if (sbi->s_es->s_feature_ro_compat &
1850             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1851                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1852                 __le32 le_group = cpu_to_le32(block_group);
1853
1854                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1855                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1856                 crc = crc16(crc, (__u8 *)gdp, offset);
1857                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1858                 /* for checksum of struct ext4_group_desc do the rest...*/
1859                 if ((sbi->s_es->s_feature_incompat &
1860                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1861                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1862                         crc = crc16(crc, (__u8 *)gdp + offset,
1863                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1864                                         offset);
1865         }
1866
1867         return cpu_to_le16(crc);
1868 }
1869
1870 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1871                                 struct ext4_group_desc *gdp)
1872 {
1873         if ((sbi->s_es->s_feature_ro_compat &
1874              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1875             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1876                 return 0;
1877
1878         return 1;
1879 }
1880
1881 /* Called at mount-time, super-block is locked */
1882 static int ext4_check_descriptors(struct super_block *sb)
1883 {
1884         struct ext4_sb_info *sbi = EXT4_SB(sb);
1885         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1886         ext4_fsblk_t last_block;
1887         ext4_fsblk_t block_bitmap;
1888         ext4_fsblk_t inode_bitmap;
1889         ext4_fsblk_t inode_table;
1890         int flexbg_flag = 0;
1891         ext4_group_t i;
1892
1893         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1894                 flexbg_flag = 1;
1895
1896         ext4_debug("Checking group descriptors");
1897
1898         for (i = 0; i < sbi->s_groups_count; i++) {
1899                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1900
1901                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1902                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1903                 else
1904                         last_block = first_block +
1905                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1906
1907                 block_bitmap = ext4_block_bitmap(sb, gdp);
1908                 if (block_bitmap < first_block || block_bitmap > last_block) {
1909                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1910                                "Block bitmap for group %u not in group "
1911                                "(block %llu)!", i, block_bitmap);
1912                         return 0;
1913                 }
1914                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1915                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1916                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1917                                "Inode bitmap for group %u not in group "
1918                                "(block %llu)!", i, inode_bitmap);
1919                         return 0;
1920                 }
1921                 inode_table = ext4_inode_table(sb, gdp);
1922                 if (inode_table < first_block ||
1923                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1924                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1925                                "Inode table for group %u not in group "
1926                                "(block %llu)!", i, inode_table);
1927                         return 0;
1928                 }
1929                 ext4_lock_group(sb, i);
1930                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1931                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1932                                  "Checksum for group %u failed (%u!=%u)",
1933                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1934                                      gdp)), le16_to_cpu(gdp->bg_checksum));
1935                         if (!(sb->s_flags & MS_RDONLY)) {
1936                                 ext4_unlock_group(sb, i);
1937                                 return 0;
1938                         }
1939                 }
1940                 ext4_unlock_group(sb, i);
1941                 if (!flexbg_flag)
1942                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
1943         }
1944
1945         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1946         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1947         return 1;
1948 }
1949
1950 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1951  * the superblock) which were deleted from all directories, but held open by
1952  * a process at the time of a crash.  We walk the list and try to delete these
1953  * inodes at recovery time (only with a read-write filesystem).
1954  *
1955  * In order to keep the orphan inode chain consistent during traversal (in
1956  * case of crash during recovery), we link each inode into the superblock
1957  * orphan list_head and handle it the same way as an inode deletion during
1958  * normal operation (which journals the operations for us).
1959  *
1960  * We only do an iget() and an iput() on each inode, which is very safe if we
1961  * accidentally point at an in-use or already deleted inode.  The worst that
1962  * can happen in this case is that we get a "bit already cleared" message from
1963  * ext4_free_inode().  The only reason we would point at a wrong inode is if
1964  * e2fsck was run on this filesystem, and it must have already done the orphan
1965  * inode cleanup for us, so we can safely abort without any further action.
1966  */
1967 static void ext4_orphan_cleanup(struct super_block *sb,
1968                                 struct ext4_super_block *es)
1969 {
1970         unsigned int s_flags = sb->s_flags;
1971         int nr_orphans = 0, nr_truncates = 0;
1972 #ifdef CONFIG_QUOTA
1973         int i;
1974 #endif
1975         if (!es->s_last_orphan) {
1976                 jbd_debug(4, "no orphan inodes to clean up\n");
1977                 return;
1978         }
1979
1980         if (bdev_read_only(sb->s_bdev)) {
1981                 ext4_msg(sb, KERN_ERR, "write access "
1982                         "unavailable, skipping orphan cleanup");
1983                 return;
1984         }
1985
1986         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1987                 if (es->s_last_orphan)
1988                         jbd_debug(1, "Errors on filesystem, "
1989                                   "clearing orphan list.\n");
1990                 es->s_last_orphan = 0;
1991                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1992                 return;
1993         }
1994
1995         if (s_flags & MS_RDONLY) {
1996                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
1997                 sb->s_flags &= ~MS_RDONLY;
1998         }
1999 #ifdef CONFIG_QUOTA
2000         /* Needed for iput() to work correctly and not trash data */
2001         sb->s_flags |= MS_ACTIVE;
2002         /* Turn on quotas so that they are updated correctly */
2003         for (i = 0; i < MAXQUOTAS; i++) {
2004                 if (EXT4_SB(sb)->s_qf_names[i]) {
2005                         int ret = ext4_quota_on_mount(sb, i);
2006                         if (ret < 0)
2007                                 ext4_msg(sb, KERN_ERR,
2008                                         "Cannot turn on journaled "
2009                                         "quota: error %d", ret);
2010                 }
2011         }
2012 #endif
2013
2014         while (es->s_last_orphan) {
2015                 struct inode *inode;
2016
2017                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2018                 if (IS_ERR(inode)) {
2019                         es->s_last_orphan = 0;
2020                         break;
2021                 }
2022
2023                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2024                 dquot_initialize(inode);
2025                 if (inode->i_nlink) {
2026                         ext4_msg(sb, KERN_DEBUG,
2027                                 "%s: truncating inode %lu to %lld bytes",
2028                                 __func__, inode->i_ino, inode->i_size);
2029                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2030                                   inode->i_ino, inode->i_size);
2031                         ext4_truncate(inode);
2032                         nr_truncates++;
2033                 } else {
2034                         ext4_msg(sb, KERN_DEBUG,
2035                                 "%s: deleting unreferenced inode %lu",
2036                                 __func__, inode->i_ino);
2037                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2038                                   inode->i_ino);
2039                         nr_orphans++;
2040                 }
2041                 iput(inode);  /* The delete magic happens here! */
2042         }
2043
2044 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2045
2046         if (nr_orphans)
2047                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2048                        PLURAL(nr_orphans));
2049         if (nr_truncates)
2050                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2051                        PLURAL(nr_truncates));
2052 #ifdef CONFIG_QUOTA
2053         /* Turn quotas off */
2054         for (i = 0; i < MAXQUOTAS; i++) {
2055                 if (sb_dqopt(sb)->files[i])
2056                         vfs_quota_off(sb, i);
2057         }
2058 #endif
2059         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2060 }
2061
2062 /*
2063  * Maximal extent format file size.
2064  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2065  * extent format containers, within a sector_t, and within i_blocks
2066  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2067  * so that won't be a limiting factor.
2068  *
2069  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2070  */
2071 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2072 {
2073         loff_t res;
2074         loff_t upper_limit = MAX_LFS_FILESIZE;
2075
2076         /* small i_blocks in vfs inode? */
2077         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2078                 /*
2079                  * CONFIG_LBDAF is not enabled implies the inode
2080                  * i_block represent total blocks in 512 bytes
2081                  * 32 == size of vfs inode i_blocks * 8
2082                  */
2083                 upper_limit = (1LL << 32) - 1;
2084
2085                 /* total blocks in file system block size */
2086                 upper_limit >>= (blkbits - 9);
2087                 upper_limit <<= blkbits;
2088         }
2089
2090         /* 32-bit extent-start container, ee_block */
2091         res = 1LL << 32;
2092         res <<= blkbits;
2093         res -= 1;
2094
2095         /* Sanity check against vm- & vfs- imposed limits */
2096         if (res > upper_limit)
2097                 res = upper_limit;
2098
2099         return res;
2100 }
2101
2102 /*
2103  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2104  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2105  * We need to be 1 filesystem block less than the 2^48 sector limit.
2106  */
2107 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2108 {
2109         loff_t res = EXT4_NDIR_BLOCKS;
2110         int meta_blocks;
2111         loff_t upper_limit;
2112         /* This is calculated to be the largest file size for a dense, block
2113          * mapped file such that the file's total number of 512-byte sectors,
2114          * including data and all indirect blocks, does not exceed (2^48 - 1).
2115          *
2116          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2117          * number of 512-byte sectors of the file.
2118          */
2119
2120         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2121                 /*
2122                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2123                  * the inode i_block field represents total file blocks in
2124                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2125                  */
2126                 upper_limit = (1LL << 32) - 1;
2127
2128                 /* total blocks in file system block size */
2129                 upper_limit >>= (bits - 9);
2130
2131         } else {
2132                 /*
2133                  * We use 48 bit ext4_inode i_blocks
2134                  * With EXT4_HUGE_FILE_FL set the i_blocks
2135                  * represent total number of blocks in
2136                  * file system block size
2137                  */
2138                 upper_limit = (1LL << 48) - 1;
2139
2140         }
2141
2142         /* indirect blocks */
2143         meta_blocks = 1;
2144         /* double indirect blocks */
2145         meta_blocks += 1 + (1LL << (bits-2));
2146         /* tripple indirect blocks */
2147         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2148
2149         upper_limit -= meta_blocks;
2150         upper_limit <<= bits;
2151
2152         res += 1LL << (bits-2);
2153         res += 1LL << (2*(bits-2));
2154         res += 1LL << (3*(bits-2));
2155         res <<= bits;
2156         if (res > upper_limit)
2157                 res = upper_limit;
2158
2159         if (res > MAX_LFS_FILESIZE)
2160                 res = MAX_LFS_FILESIZE;
2161
2162         return res;
2163 }
2164
2165 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2166                                    ext4_fsblk_t logical_sb_block, int nr)
2167 {
2168         struct ext4_sb_info *sbi = EXT4_SB(sb);
2169         ext4_group_t bg, first_meta_bg;
2170         int has_super = 0;
2171
2172         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2173
2174         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2175             nr < first_meta_bg)
2176                 return logical_sb_block + nr + 1;
2177         bg = sbi->s_desc_per_block * nr;
2178         if (ext4_bg_has_super(sb, bg))
2179                 has_super = 1;
2180
2181         return (has_super + ext4_group_first_block_no(sb, bg));
2182 }
2183
2184 /**
2185  * ext4_get_stripe_size: Get the stripe size.
2186  * @sbi: In memory super block info
2187  *
2188  * If we have specified it via mount option, then
2189  * use the mount option value. If the value specified at mount time is
2190  * greater than the blocks per group use the super block value.
2191  * If the super block value is greater than blocks per group return 0.
2192  * Allocator needs it be less than blocks per group.
2193  *
2194  */
2195 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2196 {
2197         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2198         unsigned long stripe_width =
2199                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2200
2201         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2202                 return sbi->s_stripe;
2203
2204         if (stripe_width <= sbi->s_blocks_per_group)
2205                 return stripe_width;
2206
2207         if (stride <= sbi->s_blocks_per_group)
2208                 return stride;
2209
2210         return 0;
2211 }
2212
2213 /* sysfs supprt */
2214
2215 struct ext4_attr {
2216         struct attribute attr;
2217         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2218         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *, 
2219                          const char *, size_t);
2220         int offset;
2221 };
2222
2223 static int parse_strtoul(const char *buf,
2224                 unsigned long max, unsigned long *value)
2225 {
2226         char *endp;
2227
2228         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2229         endp = skip_spaces(endp);
2230         if (*endp || *value > max)
2231                 return -EINVAL;
2232
2233         return 0;
2234 }
2235
2236 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2237                                               struct ext4_sb_info *sbi,
2238                                               char *buf)
2239 {
2240         return snprintf(buf, PAGE_SIZE, "%llu\n",
2241                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2242 }
2243
2244 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2245                                          struct ext4_sb_info *sbi, char *buf)
2246 {
2247         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2248
2249         return snprintf(buf, PAGE_SIZE, "%lu\n",
2250                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2251                          sbi->s_sectors_written_start) >> 1);
2252 }
2253
2254 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2255                                           struct ext4_sb_info *sbi, char *buf)
2256 {
2257         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2258
2259         return snprintf(buf, PAGE_SIZE, "%llu\n",
2260                         (unsigned long long)(sbi->s_kbytes_written +
2261                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2262                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2263 }
2264
2265 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2266                                           struct ext4_sb_info *sbi,
2267                                           const char *buf, size_t count)
2268 {
2269         unsigned long t;
2270
2271         if (parse_strtoul(buf, 0x40000000, &t))
2272                 return -EINVAL;
2273
2274         if (!is_power_of_2(t))
2275                 return -EINVAL;
2276
2277         sbi->s_inode_readahead_blks = t;
2278         return count;
2279 }
2280
2281 static ssize_t sbi_ui_show(struct ext4_attr *a,
2282                            struct ext4_sb_info *sbi, char *buf)
2283 {
2284         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2285
2286         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2287 }
2288
2289 static ssize_t sbi_ui_store(struct ext4_attr *a,
2290                             struct ext4_sb_info *sbi,
2291                             const char *buf, size_t count)
2292 {
2293         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2294         unsigned long t;
2295
2296         if (parse_strtoul(buf, 0xffffffff, &t))
2297                 return -EINVAL;
2298         *ui = t;
2299         return count;
2300 }
2301
2302 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2303 static struct ext4_attr ext4_attr_##_name = {                   \
2304         .attr = {.name = __stringify(_name), .mode = _mode },   \
2305         .show   = _show,                                        \
2306         .store  = _store,                                       \
2307         .offset = offsetof(struct ext4_sb_info, _elname),       \
2308 }
2309 #define EXT4_ATTR(name, mode, show, store) \
2310 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2311
2312 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2313 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2314 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2315         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2316 #define ATTR_LIST(name) &ext4_attr_##name.attr
2317
2318 EXT4_RO_ATTR(delayed_allocation_blocks);
2319 EXT4_RO_ATTR(session_write_kbytes);
2320 EXT4_RO_ATTR(lifetime_write_kbytes);
2321 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2322                  inode_readahead_blks_store, s_inode_readahead_blks);
2323 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2324 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2325 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2326 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2327 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2328 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2329 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2330 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2331
2332 static struct attribute *ext4_attrs[] = {
2333         ATTR_LIST(delayed_allocation_blocks),
2334         ATTR_LIST(session_write_kbytes),
2335         ATTR_LIST(lifetime_write_kbytes),
2336         ATTR_LIST(inode_readahead_blks),
2337         ATTR_LIST(inode_goal),
2338         ATTR_LIST(mb_stats),
2339         ATTR_LIST(mb_max_to_scan),
2340         ATTR_LIST(mb_min_to_scan),
2341         ATTR_LIST(mb_order2_req),
2342         ATTR_LIST(mb_stream_req),
2343         ATTR_LIST(mb_group_prealloc),
2344         ATTR_LIST(max_writeback_mb_bump),
2345         NULL,
2346 };
2347
2348 static ssize_t ext4_attr_show(struct kobject *kobj,
2349                               struct attribute *attr, char *buf)
2350 {
2351         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2352                                                 s_kobj);
2353         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2354
2355         return a->show ? a->show(a, sbi, buf) : 0;
2356 }
2357
2358 static ssize_t ext4_attr_store(struct kobject *kobj,
2359                                struct attribute *attr,
2360                                const char *buf, size_t len)
2361 {
2362         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2363                                                 s_kobj);
2364         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2365
2366         return a->store ? a->store(a, sbi, buf, len) : 0;
2367 }
2368
2369 static void ext4_sb_release(struct kobject *kobj)
2370 {
2371         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2372                                                 s_kobj);
2373         complete(&sbi->s_kobj_unregister);
2374 }
2375
2376
2377 static const struct sysfs_ops ext4_attr_ops = {
2378         .show   = ext4_attr_show,
2379         .store  = ext4_attr_store,
2380 };
2381
2382 static struct kobj_type ext4_ktype = {
2383         .default_attrs  = ext4_attrs,
2384         .sysfs_ops      = &ext4_attr_ops,
2385         .release        = ext4_sb_release,
2386 };
2387
2388 /*
2389  * Check whether this filesystem can be mounted based on
2390  * the features present and the RDONLY/RDWR mount requested.
2391  * Returns 1 if this filesystem can be mounted as requested,
2392  * 0 if it cannot be.
2393  */
2394 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2395 {
2396         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2397                 ext4_msg(sb, KERN_ERR,
2398                         "Couldn't mount because of "
2399                         "unsupported optional features (%x)",
2400                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2401                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2402                 return 0;
2403         }
2404
2405         if (readonly)
2406                 return 1;
2407
2408         /* Check that feature set is OK for a read-write mount */
2409         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2410                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2411                          "unsupported optional features (%x)",
2412                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2413                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2414                 return 0;
2415         }
2416         /*
2417          * Large file size enabled file system can only be mounted
2418          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2419          */
2420         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2421                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2422                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2423                                  "cannot be mounted RDWR without "
2424                                  "CONFIG_LBDAF");
2425                         return 0;
2426                 }
2427         }
2428         return 1;
2429 }
2430
2431 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2432                                 __releases(kernel_lock)
2433                                 __acquires(kernel_lock)
2434 {
2435         struct buffer_head *bh;
2436         struct ext4_super_block *es = NULL;
2437         struct ext4_sb_info *sbi;
2438         ext4_fsblk_t block;
2439         ext4_fsblk_t sb_block = get_sb_block(&data);
2440         ext4_fsblk_t logical_sb_block;
2441         unsigned long offset = 0;
2442         unsigned long journal_devnum = 0;
2443         unsigned long def_mount_opts;
2444         struct inode *root;
2445         char *cp;
2446         const char *descr;
2447         int ret = -EINVAL;
2448         int blocksize;
2449         unsigned int db_count;
2450         unsigned int i;
2451         int needs_recovery, has_huge_files;
2452         __u64 blocks_count;
2453         int err;
2454         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2455
2456         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2457         if (!sbi)
2458                 return -ENOMEM;
2459
2460         sbi->s_blockgroup_lock =
2461                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2462         if (!sbi->s_blockgroup_lock) {
2463                 kfree(sbi);
2464                 return -ENOMEM;
2465         }
2466         sb->s_fs_info = sbi;
2467         sbi->s_mount_opt = 0;
2468         sbi->s_resuid = EXT4_DEF_RESUID;
2469         sbi->s_resgid = EXT4_DEF_RESGID;
2470         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2471         sbi->s_sb_block = sb_block;
2472         sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2473                                                       sectors[1]);
2474
2475         unlock_kernel();
2476
2477         /* Cleanup superblock name */
2478         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2479                 *cp = '!';
2480
2481         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2482         if (!blocksize) {
2483                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2484                 goto out_fail;
2485         }
2486
2487         /*
2488          * The ext4 superblock will not be buffer aligned for other than 1kB
2489          * block sizes.  We need to calculate the offset from buffer start.
2490          */
2491         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2492                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2493                 offset = do_div(logical_sb_block, blocksize);
2494         } else {
2495                 logical_sb_block = sb_block;
2496         }
2497
2498         if (!(bh = sb_bread(sb, logical_sb_block))) {
2499                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2500                 goto out_fail;
2501         }
2502         /*
2503          * Note: s_es must be initialized as soon as possible because
2504          *       some ext4 macro-instructions depend on its value
2505          */
2506         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2507         sbi->s_es = es;
2508         sb->s_magic = le16_to_cpu(es->s_magic);
2509         if (sb->s_magic != EXT4_SUPER_MAGIC)
2510                 goto cantfind_ext4;
2511         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2512
2513         /* Set defaults before we parse the mount options */
2514         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2515         if (def_mount_opts & EXT4_DEFM_DEBUG)
2516                 set_opt(sbi->s_mount_opt, DEBUG);
2517         if (def_mount_opts & EXT4_DEFM_BSDGROUPS) {
2518                 ext4_msg(sb, KERN_WARNING, deprecated_msg, "bsdgroups",
2519                         "2.6.38");
2520                 set_opt(sbi->s_mount_opt, GRPID);
2521         }
2522         if (def_mount_opts & EXT4_DEFM_UID16)
2523                 set_opt(sbi->s_mount_opt, NO_UID32);
2524 #ifdef CONFIG_EXT4_FS_XATTR
2525         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2526                 set_opt(sbi->s_mount_opt, XATTR_USER);
2527 #endif
2528 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2529         if (def_mount_opts & EXT4_DEFM_ACL)
2530                 set_opt(sbi->s_mount_opt, POSIX_ACL);
2531 #endif
2532         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2533                 set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2534         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2535                 set_opt(sbi->s_mount_opt, ORDERED_DATA);
2536         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2537                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2538
2539         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2540                 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2541         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2542                 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2543         else
2544                 set_opt(sbi->s_mount_opt, ERRORS_RO);
2545
2546         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2547         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2548         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2549         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2550         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2551
2552         set_opt(sbi->s_mount_opt, BARRIER);
2553
2554         /*
2555          * enable delayed allocation by default
2556          * Use -o nodelalloc to turn it off
2557          */
2558         if (!IS_EXT3_SB(sb))
2559                 set_opt(sbi->s_mount_opt, DELALLOC);
2560
2561         if (!parse_options((char *) data, sb, &journal_devnum,
2562                            &journal_ioprio, NULL, 0))
2563                 goto failed_mount;
2564
2565         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2566                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
2567
2568         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2569             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2570              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2571              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2572                 ext4_msg(sb, KERN_WARNING,
2573                        "feature flags set on rev 0 fs, "
2574                        "running e2fsck is recommended");
2575
2576         /*
2577          * Check feature flags regardless of the revision level, since we
2578          * previously didn't change the revision level when setting the flags,
2579          * so there is a chance incompat flags are set on a rev 0 filesystem.
2580          */
2581         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
2582                 goto failed_mount;
2583
2584         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2585
2586         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2587             blocksize > EXT4_MAX_BLOCK_SIZE) {
2588                 ext4_msg(sb, KERN_ERR,
2589                        "Unsupported filesystem blocksize %d", blocksize);
2590                 goto failed_mount;
2591         }
2592
2593         if (sb->s_blocksize != blocksize) {
2594                 /* Validate the filesystem blocksize */
2595                 if (!sb_set_blocksize(sb, blocksize)) {
2596                         ext4_msg(sb, KERN_ERR, "bad block size %d",
2597                                         blocksize);
2598                         goto failed_mount;
2599                 }
2600
2601                 brelse(bh);
2602                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2603                 offset = do_div(logical_sb_block, blocksize);
2604                 bh = sb_bread(sb, logical_sb_block);
2605                 if (!bh) {
2606                         ext4_msg(sb, KERN_ERR,
2607                                "Can't read superblock on 2nd try");
2608                         goto failed_mount;
2609                 }
2610                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2611                 sbi->s_es = es;
2612                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2613                         ext4_msg(sb, KERN_ERR,
2614                                "Magic mismatch, very weird!");
2615                         goto failed_mount;
2616                 }
2617         }
2618
2619         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2620                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2621         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2622                                                       has_huge_files);
2623         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2624
2625         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2626                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2627                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2628         } else {
2629                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2630                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2631                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2632                     (!is_power_of_2(sbi->s_inode_size)) ||
2633                     (sbi->s_inode_size > blocksize)) {
2634                         ext4_msg(sb, KERN_ERR,
2635                                "unsupported inode size: %d",
2636                                sbi->s_inode_size);
2637                         goto failed_mount;
2638                 }
2639                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2640                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2641         }
2642
2643         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2644         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2645                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2646                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2647                     !is_power_of_2(sbi->s_desc_size)) {
2648                         ext4_msg(sb, KERN_ERR,
2649                                "unsupported descriptor size %lu",
2650                                sbi->s_desc_size);
2651                         goto failed_mount;
2652                 }
2653         } else
2654                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2655
2656         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2657         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2658         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2659                 goto cantfind_ext4;
2660
2661         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2662         if (sbi->s_inodes_per_block == 0)
2663                 goto cantfind_ext4;
2664         sbi->s_itb_per_group = sbi->s_inodes_per_group /
2665                                         sbi->s_inodes_per_block;
2666         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2667         sbi->s_sbh = bh;
2668         sbi->s_mount_state = le16_to_cpu(es->s_state);
2669         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2670         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2671
2672         for (i = 0; i < 4; i++)
2673                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2674         sbi->s_def_hash_version = es->s_def_hash_version;
2675         i = le32_to_cpu(es->s_flags);
2676         if (i & EXT2_FLAGS_UNSIGNED_HASH)
2677                 sbi->s_hash_unsigned = 3;
2678         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2679 #ifdef __CHAR_UNSIGNED__
2680                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2681                 sbi->s_hash_unsigned = 3;
2682 #else
2683                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2684 #endif
2685                 sb->s_dirt = 1;
2686         }
2687
2688         if (sbi->s_blocks_per_group > blocksize * 8) {
2689                 ext4_msg(sb, KERN_ERR,
2690                        "#blocks per group too big: %lu",
2691                        sbi->s_blocks_per_group);
2692                 goto failed_mount;
2693         }
2694         if (sbi->s_inodes_per_group > blocksize * 8) {
2695                 ext4_msg(sb, KERN_ERR,
2696                        "#inodes per group too big: %lu",
2697                        sbi->s_inodes_per_group);
2698                 goto failed_mount;
2699         }
2700
2701         /*
2702          * Test whether we have more sectors than will fit in sector_t,
2703          * and whether the max offset is addressable by the page cache.
2704          */
2705         if ((ext4_blocks_count(es) >
2706              (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
2707             (ext4_blocks_count(es) >
2708              (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
2709                 ext4_msg(sb, KERN_ERR, "filesystem"
2710                          " too large to mount safely on this system");
2711                 if (sizeof(sector_t) < 8)
2712                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
2713                 ret = -EFBIG;
2714                 goto failed_mount;
2715         }
2716
2717         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2718                 goto cantfind_ext4;
2719
2720         /* check blocks count against device size */
2721         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2722         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2723                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2724                        "exceeds size of device (%llu blocks)",
2725                        ext4_blocks_count(es), blocks_count);
2726                 goto failed_mount;
2727         }
2728
2729         /*
2730          * It makes no sense for the first data block to be beyond the end
2731          * of the filesystem.
2732          */
2733         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2734                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2735                          "block %u is beyond end of filesystem (%llu)",
2736                          le32_to_cpu(es->s_first_data_block),
2737                          ext4_blocks_count(es));
2738                 goto failed_mount;
2739         }
2740         blocks_count = (ext4_blocks_count(es) -
2741                         le32_to_cpu(es->s_first_data_block) +
2742                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
2743         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2744         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2745                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2746                        "(block count %llu, first data block %u, "
2747                        "blocks per group %lu)", sbi->s_groups_count,
2748                        ext4_blocks_count(es),
2749                        le32_to_cpu(es->s_first_data_block),
2750                        EXT4_BLOCKS_PER_GROUP(sb));
2751                 goto failed_mount;
2752         }
2753         sbi->s_groups_count = blocks_count;
2754         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
2755                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
2756         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2757                    EXT4_DESC_PER_BLOCK(sb);
2758         sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2759                                     GFP_KERNEL);
2760         if (sbi->s_group_desc == NULL) {
2761                 ext4_msg(sb, KERN_ERR, "not enough memory");
2762                 goto failed_mount;
2763         }
2764
2765 #ifdef CONFIG_PROC_FS
2766         if (ext4_proc_root)
2767                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2768 #endif
2769
2770         bgl_lock_init(sbi->s_blockgroup_lock);
2771
2772         for (i = 0; i < db_count; i++) {
2773                 block = descriptor_loc(sb, logical_sb_block, i);
2774                 sbi->s_group_desc[i] = sb_bread(sb, block);
2775                 if (!sbi->s_group_desc[i]) {
2776                         ext4_msg(sb, KERN_ERR,
2777                                "can't read group descriptor %d", i);
2778                         db_count = i;
2779                         goto failed_mount2;
2780                 }
2781         }
2782         if (!ext4_check_descriptors(sb)) {
2783                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2784                 goto failed_mount2;
2785         }
2786         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2787                 if (!ext4_fill_flex_info(sb)) {
2788                         ext4_msg(sb, KERN_ERR,
2789                                "unable to initialize "
2790                                "flex_bg meta info!");
2791                         goto failed_mount2;
2792                 }
2793
2794         sbi->s_gdb_count = db_count;
2795         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2796         spin_lock_init(&sbi->s_next_gen_lock);
2797
2798         err = percpu_counter_init(&sbi->s_freeblocks_counter,
2799                         ext4_count_free_blocks(sb));
2800         if (!err) {
2801                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2802                                 ext4_count_free_inodes(sb));
2803         }
2804         if (!err) {
2805                 err = percpu_counter_init(&sbi->s_dirs_counter,
2806                                 ext4_count_dirs(sb));
2807         }
2808         if (!err) {
2809                 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2810         }
2811         if (err) {
2812                 ext4_msg(sb, KERN_ERR, "insufficient memory");
2813                 goto failed_mount3;
2814         }
2815
2816         sbi->s_stripe = ext4_get_stripe_size(sbi);
2817         sbi->s_max_writeback_mb_bump = 128;
2818
2819         /*
2820          * set up enough so that it can read an inode
2821          */
2822         if (!test_opt(sb, NOLOAD) &&
2823             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2824                 sb->s_op = &ext4_sops;
2825         else
2826                 sb->s_op = &ext4_nojournal_sops;
2827         sb->s_export_op = &ext4_export_ops;
2828         sb->s_xattr = ext4_xattr_handlers;
2829 #ifdef CONFIG_QUOTA
2830         sb->s_qcop = &ext4_qctl_operations;
2831         sb->dq_op = &ext4_quota_operations;
2832 #endif
2833         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2834         mutex_init(&sbi->s_orphan_lock);
2835         mutex_init(&sbi->s_resize_lock);
2836
2837         sb->s_root = NULL;
2838
2839         needs_recovery = (es->s_last_orphan != 0 ||
2840                           EXT4_HAS_INCOMPAT_FEATURE(sb,
2841                                     EXT4_FEATURE_INCOMPAT_RECOVER));
2842
2843         /*
2844          * The first inode we look at is the journal inode.  Don't try
2845          * root first: it may be modified in the journal!
2846          */
2847         if (!test_opt(sb, NOLOAD) &&
2848             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2849                 if (ext4_load_journal(sb, es, journal_devnum))
2850                         goto failed_mount3;
2851         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2852               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2853                 ext4_msg(sb, KERN_ERR, "required journal recovery "
2854                        "suppressed and not mounted read-only");
2855                 goto failed_mount_wq;
2856         } else {
2857                 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2858                 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2859                 sbi->s_journal = NULL;
2860                 needs_recovery = 0;
2861                 goto no_journal;
2862         }
2863
2864         if (ext4_blocks_count(es) > 0xffffffffULL &&
2865             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2866                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
2867                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
2868                 goto failed_mount_wq;
2869         }
2870
2871         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2872                 jbd2_journal_set_features(sbi->s_journal,
2873                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2874                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2875         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2876                 jbd2_journal_set_features(sbi->s_journal,
2877                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2878                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2879                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2880         } else {
2881                 jbd2_journal_clear_features(sbi->s_journal,
2882                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2883                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2884         }
2885
2886         /* We have now updated the journal if required, so we can
2887          * validate the data journaling mode. */
2888         switch (test_opt(sb, DATA_FLAGS)) {
2889         case 0:
2890                 /* No mode set, assume a default based on the journal
2891                  * capabilities: ORDERED_DATA if the journal can
2892                  * cope, else JOURNAL_DATA
2893                  */
2894                 if (jbd2_journal_check_available_features
2895                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2896                         set_opt(sbi->s_mount_opt, ORDERED_DATA);
2897                 else
2898                         set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2899                 break;
2900
2901         case EXT4_MOUNT_ORDERED_DATA:
2902         case EXT4_MOUNT_WRITEBACK_DATA:
2903                 if (!jbd2_journal_check_available_features
2904                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2905                         ext4_msg(sb, KERN_ERR, "Journal does not support "
2906                                "requested data journaling mode");
2907                         goto failed_mount_wq;
2908                 }
2909         default:
2910                 break;
2911         }
2912         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2913
2914 no_journal:
2915         if (test_opt(sb, NOBH)) {
2916                 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2917                         ext4_msg(sb, KERN_WARNING, "Ignoring nobh option - "
2918                                 "its supported only with writeback mode");
2919                         clear_opt(sbi->s_mount_opt, NOBH);
2920                 }
2921                 if (test_opt(sb, DIOREAD_NOLOCK)) {
2922                         ext4_msg(sb, KERN_WARNING, "dioread_nolock option is "
2923                                 "not supported with nobh mode");
2924                         goto failed_mount_wq;
2925                 }
2926         }
2927         EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten");
2928         if (!EXT4_SB(sb)->dio_unwritten_wq) {
2929                 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
2930                 goto failed_mount_wq;
2931         }
2932
2933         /*
2934          * The jbd2_journal_load will have done any necessary log recovery,
2935          * so we can safely mount the rest of the filesystem now.
2936          */
2937
2938         root = ext4_iget(sb, EXT4_ROOT_INO);
2939         if (IS_ERR(root)) {
2940                 ext4_msg(sb, KERN_ERR, "get root inode failed");
2941                 ret = PTR_ERR(root);
2942                 goto failed_mount4;
2943         }
2944         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2945                 iput(root);
2946                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
2947                 goto failed_mount4;
2948         }
2949         sb->s_root = d_alloc_root(root);
2950         if (!sb->s_root) {
2951                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
2952                 iput(root);
2953                 ret = -ENOMEM;
2954                 goto failed_mount4;
2955         }
2956
2957         ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2958
2959         /* determine the minimum size of new large inodes, if present */
2960         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2961                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2962                                                      EXT4_GOOD_OLD_INODE_SIZE;
2963                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2964                                        EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2965                         if (sbi->s_want_extra_isize <
2966                             le16_to_cpu(es->s_want_extra_isize))
2967                                 sbi->s_want_extra_isize =
2968                                         le16_to_cpu(es->s_want_extra_isize);
2969                         if (sbi->s_want_extra_isize <
2970                             le16_to_cpu(es->s_min_extra_isize))
2971                                 sbi->s_want_extra_isize =
2972                                         le16_to_cpu(es->s_min_extra_isize);
2973                 }
2974         }
2975         /* Check if enough inode space is available */
2976         if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2977                                                         sbi->s_inode_size) {
2978                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2979                                                        EXT4_GOOD_OLD_INODE_SIZE;
2980                 ext4_msg(sb, KERN_INFO, "required extra inode space not"
2981                          "available");
2982         }
2983
2984         if (test_opt(sb, DELALLOC) &&
2985             (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2986                 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
2987                          "requested data journaling mode");
2988                 clear_opt(sbi->s_mount_opt, DELALLOC);
2989         }
2990         if (test_opt(sb, DIOREAD_NOLOCK)) {
2991                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
2992                         ext4_msg(sb, KERN_WARNING, "Ignoring dioread_nolock "
2993                                 "option - requested data journaling mode");
2994                         clear_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
2995                 }
2996                 if (sb->s_blocksize < PAGE_SIZE) {
2997                         ext4_msg(sb, KERN_WARNING, "Ignoring dioread_nolock "
2998                                 "option - block size is too small");
2999                         clear_opt(sbi->s_mount_opt, DIOREAD_NOLOCK);
3000                 }
3001         }
3002
3003         err = ext4_setup_system_zone(sb);
3004         if (err) {
3005                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
3006                          "zone (%d)\n", err);
3007                 goto failed_mount4;
3008         }
3009
3010         ext4_ext_init(sb);
3011         err = ext4_mb_init(sb, needs_recovery);
3012         if (err) {
3013                 ext4_msg(sb, KERN_ERR, "failed to initalize mballoc (%d)",
3014                          err);
3015                 goto failed_mount4;
3016         }
3017
3018         sbi->s_kobj.kset = ext4_kset;
3019         init_completion(&sbi->s_kobj_unregister);
3020         err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
3021                                    "%s", sb->s_id);
3022         if (err) {
3023                 ext4_mb_release(sb);
3024                 ext4_ext_release(sb);
3025                 goto failed_mount4;
3026         };
3027
3028         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
3029         ext4_orphan_cleanup(sb, es);
3030         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
3031         if (needs_recovery) {
3032                 ext4_msg(sb, KERN_INFO, "recovery complete");
3033                 ext4_mark_recovery_complete(sb, es);
3034         }
3035         if (EXT4_SB(sb)->s_journal) {
3036                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
3037                         descr = " journalled data mode";
3038                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
3039                         descr = " ordered data mode";
3040                 else
3041                         descr = " writeback data mode";
3042         } else
3043                 descr = "out journal";
3044
3045         ext4_msg(sb, KERN_INFO, "mounted filesystem with%s", descr);
3046
3047         lock_kernel();
3048         return 0;
3049
3050 cantfind_ext4:
3051         if (!silent)
3052                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
3053         goto failed_mount;
3054
3055 failed_mount4:
3056         ext4_msg(sb, KERN_ERR, "mount failed");
3057         destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
3058 failed_mount_wq:
3059         ext4_release_system_zone(sb);
3060         if (sbi->s_journal) {
3061                 jbd2_journal_destroy(sbi->s_journal);
3062                 sbi->s_journal = NULL;
3063         }
3064 failed_mount3:
3065         if (sbi->s_flex_groups) {
3066                 if (is_vmalloc_addr(sbi->s_flex_groups))
3067                         vfree(sbi->s_flex_groups);
3068                 else
3069                         kfree(sbi->s_flex_groups);
3070         }
3071         percpu_counter_destroy(&sbi->s_freeblocks_counter);
3072         percpu_counter_destroy(&sbi->s_freeinodes_counter);
3073         percpu_counter_destroy(&sbi->s_dirs_counter);
3074         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
3075 failed_mount2:
3076         for (i = 0; i < db_count; i++)
3077                 brelse(sbi->s_group_desc[i]);
3078         kfree(sbi->s_group_desc);
3079 failed_mount:
3080         if (sbi->s_proc) {
3081                 remove_proc_entry(sb->s_id, ext4_proc_root);
3082         }
3083 #ifdef CONFIG_QUOTA
3084         for (i = 0; i < MAXQUOTAS; i++)
3085                 kfree(sbi->s_qf_names[i]);
3086 #endif
3087         ext4_blkdev_remove(sbi);
3088         brelse(bh);
3089 out_fail:
3090         sb->s_fs_info = NULL;
3091         kfree(sbi->s_blockgroup_lock);
3092         kfree(sbi);
3093         lock_kernel();
3094         return ret;
3095 }
3096
3097 /*
3098  * Setup any per-fs journal parameters now.  We'll do this both on
3099  * initial mount, once the journal has been initialised but before we've
3100  * done any recovery; and again on any subsequent remount.
3101  */
3102 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
3103 {
3104         struct ext4_sb_info *sbi = EXT4_SB(sb);
3105
3106         journal->j_commit_interval = sbi->s_commit_interval;
3107         journal->j_min_batch_time = sbi->s_min_batch_time;
3108         journal->j_max_batch_time = sbi->s_max_batch_time;
3109
3110         spin_lock(&journal->j_state_lock);
3111         if (test_opt(sb, BARRIER))
3112                 journal->j_flags |= JBD2_BARRIER;
3113         else
3114                 journal->j_flags &= ~JBD2_BARRIER;
3115         if (test_opt(sb, DATA_ERR_ABORT))
3116                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3117         else
3118                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3119         spin_unlock(&journal->j_state_lock);
3120 }
3121
3122 static journal_t *ext4_get_journal(struct super_block *sb,
3123                                    unsigned int journal_inum)
3124 {
3125         struct inode *journal_inode;
3126         journal_t *journal;
3127
3128         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3129
3130         /* First, test for the existence of a valid inode on disk.  Bad
3131          * things happen if we iget() an unused inode, as the subsequent
3132          * iput() will try to delete it. */
3133
3134         journal_inode = ext4_iget(sb, journal_inum);
3135         if (IS_ERR(journal_inode)) {
3136                 ext4_msg(sb, KERN_ERR, "no journal found");
3137                 return NULL;
3138         }
3139         if (!journal_inode->i_nlink) {
3140                 make_bad_inode(journal_inode);
3141                 iput(journal_inode);
3142                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3143                 return NULL;
3144         }
3145
3146         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3147                   journal_inode, journal_inode->i_size);
3148         if (!S_ISREG(journal_inode->i_mode)) {
3149                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3150                 iput(journal_inode);
3151                 return NULL;
3152         }
3153
3154         journal = jbd2_journal_init_inode(journal_inode);
3155         if (!journal) {
3156                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3157                 iput(journal_inode);
3158                 return NULL;
3159         }
3160         journal->j_private = sb;
3161         ext4_init_journal_params(sb, journal);
3162         return journal;
3163 }
3164
3165 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3166                                        dev_t j_dev)
3167 {
3168         struct buffer_head *bh;
3169         journal_t *journal;
3170         ext4_fsblk_t start;
3171         ext4_fsblk_t len;
3172         int hblock, blocksize;
3173         ext4_fsblk_t sb_block;
3174         unsigned long offset;
3175         struct ext4_super_block *es;
3176         struct block_device *bdev;
3177
3178         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3179
3180         bdev = ext4_blkdev_get(j_dev, sb);
3181         if (bdev == NULL)
3182                 return NULL;
3183
3184         if (bd_claim(bdev, sb)) {
3185                 ext4_msg(sb, KERN_ERR,
3186                         "failed to claim external journal device");
3187                 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3188                 return NULL;
3189         }
3190
3191         blocksize = sb->s_blocksize;
3192         hblock = bdev_logical_block_size(bdev);
3193         if (blocksize < hblock) {
3194                 ext4_msg(sb, KERN_ERR,
3195                         "blocksize too small for journal device");
3196                 goto out_bdev;
3197         }
3198
3199         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3200         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3201         set_blocksize(bdev, blocksize);
3202         if (!(bh = __bread(bdev, sb_block, blocksize))) {
3203                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3204                        "external journal");
3205                 goto out_bdev;
3206         }
3207
3208         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3209         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3210             !(le32_to_cpu(es->s_feature_incompat) &
3211               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3212                 ext4_msg(sb, KERN_ERR, "external journal has "
3213                                         "bad superblock");
3214                 brelse(bh);
3215                 goto out_bdev;
3216         }
3217
3218         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3219                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3220                 brelse(bh);
3221                 goto out_bdev;
3222         }
3223
3224         len = ext4_blocks_count(es);
3225         start = sb_block + 1;
3226         brelse(bh);     /* we're done with the superblock */
3227
3228         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3229                                         start, len, blocksize);
3230         if (!journal) {
3231                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3232                 goto out_bdev;
3233         }
3234         journal->j_private = sb;
3235         ll_rw_block(READ, 1, &journal->j_sb_buffer);
3236         wait_on_buffer(journal->j_sb_buffer);
3237         if (!buffer_uptodate(journal->j_sb_buffer)) {
3238                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3239                 goto out_journal;
3240         }
3241         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3242                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3243                                         "user (unsupported) - %d",
3244                         be32_to_cpu(journal->j_superblock->s_nr_users));
3245                 goto out_journal;
3246         }
3247         EXT4_SB(sb)->journal_bdev = bdev;
3248         ext4_init_journal_params(sb, journal);
3249         return journal;
3250
3251 out_journal:
3252         jbd2_journal_destroy(journal);
3253 out_bdev:
3254         ext4_blkdev_put(bdev);
3255         return NULL;
3256 }
3257
3258 static int ext4_load_journal(struct super_block *sb,
3259                              struct ext4_super_block *es,
3260                              unsigned long journal_devnum)
3261 {
3262         journal_t *journal;
3263         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3264         dev_t journal_dev;
3265         int err = 0;
3266         int really_read_only;
3267
3268         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3269
3270         if (journal_devnum &&
3271             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3272                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3273                         "numbers have changed");
3274                 journal_dev = new_decode_dev(journal_devnum);
3275         } else
3276                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3277
3278         really_read_only = bdev_read_only(sb->s_bdev);
3279
3280         /*
3281          * Are we loading a blank journal or performing recovery after a
3282          * crash?  For recovery, we need to check in advance whether we
3283          * can get read-write access to the device.
3284          */
3285         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3286                 if (sb->s_flags & MS_RDONLY) {
3287                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
3288                                         "required on readonly filesystem");
3289                         if (really_read_only) {
3290                                 ext4_msg(sb, KERN_ERR, "write access "
3291                                         "unavailable, cannot proceed");
3292                                 return -EROFS;
3293                         }
3294                         ext4_msg(sb, KERN_INFO, "write access will "
3295                                "be enabled during recovery");
3296                 }
3297         }
3298
3299         if (journal_inum && journal_dev) {
3300                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3301                        "and inode journals!");
3302                 return -EINVAL;
3303         }
3304
3305         if (journal_inum) {
3306                 if (!(journal = ext4_get_journal(sb, journal_inum)))
3307                         return -EINVAL;
3308         } else {
3309                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3310                         return -EINVAL;
3311         }
3312
3313         if (!(journal->j_flags & JBD2_BARRIER))
3314                 ext4_msg(sb, KERN_INFO, "barriers disabled");
3315
3316         if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3317                 err = jbd2_journal_update_format(journal);
3318                 if (err)  {
3319                         ext4_msg(sb, KERN_ERR, "error updating journal");
3320                         jbd2_journal_destroy(journal);
3321                         return err;
3322                 }
3323         }
3324
3325         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3326                 err = jbd2_journal_wipe(journal, !really_read_only);
3327         if (!err)
3328                 err = jbd2_journal_load(journal);
3329
3330         if (err) {
3331                 ext4_msg(sb, KERN_ERR, "error loading journal");
3332                 jbd2_journal_destroy(journal);
3333                 return err;
3334         }
3335
3336         EXT4_SB(sb)->s_journal = journal;
3337         ext4_clear_journal_err(sb, es);
3338
3339         if (journal_devnum &&
3340             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3341                 es->s_journal_dev = cpu_to_le32(journal_devnum);
3342
3343                 /* Make sure we flush the recovery flag to disk. */
3344                 ext4_commit_super(sb, 1);
3345         }
3346
3347         return 0;
3348 }
3349
3350 static int ext4_commit_super(struct super_block *sb, int sync)
3351 {
3352         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3353         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3354         int error = 0;
3355
3356         if (!sbh)
3357                 return error;
3358         if (buffer_write_io_error(sbh)) {
3359                 /*
3360                  * Oh, dear.  A previous attempt to write the
3361                  * superblock failed.  This could happen because the
3362                  * USB device was yanked out.  Or it could happen to
3363                  * be a transient write error and maybe the block will
3364                  * be remapped.  Nothing we can do but to retry the
3365                  * write and hope for the best.
3366                  */
3367                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3368                        "superblock detected");
3369                 clear_buffer_write_io_error(sbh);
3370                 set_buffer_uptodate(sbh);
3371         }
3372         /*
3373          * If the file system is mounted read-only, don't update the
3374          * superblock write time.  This avoids updating the superblock
3375          * write time when we are mounting the root file system
3376          * read/only but we need to replay the journal; at that point,
3377          * for people who are east of GMT and who make their clock
3378          * tick in localtime for Windows bug-for-bug compatibility,
3379          * the clock is set in the future, and this will cause e2fsck
3380          * to complain and force a full file system check.
3381          */
3382         if (!(sb->s_flags & MS_RDONLY))
3383                 es->s_wtime = cpu_to_le32(get_seconds());
3384         es->s_kbytes_written =
3385                 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written + 
3386                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3387                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
3388         ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3389                                         &EXT4_SB(sb)->s_freeblocks_counter));
3390         es->s_free_inodes_count = cpu_to_le32(percpu_counter_sum_positive(
3391                                         &EXT4_SB(sb)->s_freeinodes_counter));
3392         sb->s_dirt = 0;
3393         BUFFER_TRACE(sbh, "marking dirty");
3394         mark_buffer_dirty(sbh);
3395         if (sync) {
3396                 error = sync_dirty_buffer(sbh);
3397                 if (error)
3398                         return error;
3399
3400                 error = buffer_write_io_error(sbh);
3401                 if (error) {
3402                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
3403                                "superblock");
3404                         clear_buffer_write_io_error(sbh);
3405                         set_buffer_uptodate(sbh);
3406                 }
3407         }
3408         return error;
3409 }
3410
3411 /*
3412  * Have we just finished recovery?  If so, and if we are mounting (or
3413  * remounting) the filesystem readonly, then we will end up with a
3414  * consistent fs on disk.  Record that fact.
3415  */
3416 static void ext4_mark_recovery_complete(struct super_block *sb,
3417                                         struct ext4_super_block *es)
3418 {
3419         journal_t *journal = EXT4_SB(sb)->s_journal;
3420
3421         if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3422                 BUG_ON(journal != NULL);
3423                 return;
3424         }
3425         jbd2_journal_lock_updates(journal);
3426         if (jbd2_journal_flush(journal) < 0)
3427                 goto out;
3428
3429         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
3430             sb->s_flags & MS_RDONLY) {
3431                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3432                 ext4_commit_super(sb, 1);
3433         }
3434
3435 out:
3436         jbd2_journal_unlock_updates(journal);
3437 }
3438
3439 /*
3440  * If we are mounting (or read-write remounting) a filesystem whose journal
3441  * has recorded an error from a previous lifetime, move that error to the
3442  * main filesystem now.
3443  */
3444 static void ext4_clear_journal_err(struct super_block *sb,
3445                                    struct ext4_super_block *es)
3446 {
3447         journal_t *journal;
3448         int j_errno;
3449         const char *errstr;
3450
3451         BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3452
3453         journal = EXT4_SB(sb)->s_journal;
3454
3455         /*
3456          * Now check for any error status which may have been recorded in the
3457          * journal by a prior ext4_error() or ext4_abort()
3458          */
3459
3460         j_errno = jbd2_journal_errno(journal);
3461         if (j_errno) {
3462                 char nbuf[16];
3463
3464                 errstr = ext4_decode_error(sb, j_errno, nbuf);
3465                 ext4_warning(sb, "Filesystem error recorded "
3466                              "from previous mount: %s", errstr);
3467                 ext4_warning(sb, "Marking fs in need of filesystem check.");
3468
3469                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
3470                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
3471                 ext4_commit_super(sb, 1);
3472
3473                 jbd2_journal_clear_err(journal);
3474         }
3475 }
3476
3477 /*
3478  * Force the running and committing transactions to commit,
3479  * and wait on the commit.
3480  */
3481 int ext4_force_commit(struct super_block *sb)
3482 {
3483         journal_t *journal;
3484         int ret = 0;
3485
3486         if (sb->s_flags & MS_RDONLY)
3487                 return 0;
3488
3489         journal = EXT4_SB(sb)->s_journal;
3490         if (journal)
3491                 ret = ext4_journal_force_commit(journal);
3492
3493         return ret;
3494 }
3495
3496 static void ext4_write_super(struct super_block *sb)
3497 {
3498         lock_super(sb);
3499         ext4_commit_super(sb, 1);
3500         unlock_super(sb);
3501 }
3502
3503 static int ext4_sync_fs(struct super_block *sb, int wait)
3504 {
3505         int ret = 0;
3506         tid_t target;
3507         struct ext4_sb_info *sbi = EXT4_SB(sb);
3508
3509         trace_ext4_sync_fs(sb, wait);
3510         flush_workqueue(sbi->dio_unwritten_wq);
3511         if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
3512                 if (wait)
3513                         jbd2_log_wait_commit(sbi->s_journal, target);
3514         }
3515         return ret;
3516 }
3517
3518 /*
3519  * LVM calls this function before a (read-only) snapshot is created.  This
3520  * gives us a chance to flush the journal completely and mark the fs clean.
3521  */
3522 static int ext4_freeze(struct super_block *sb)
3523 {
3524         int error = 0;
3525         journal_t *journal;
3526
3527         if (sb->s_flags & MS_RDONLY)
3528                 return 0;
3529
3530         journal = EXT4_SB(sb)->s_journal;
3531
3532         /* Now we set up the journal barrier. */
3533         jbd2_journal_lock_updates(journal);
3534
3535         /*
3536          * Don't clear the needs_recovery flag if we failed to flush
3537          * the journal.
3538          */
3539         error = jbd2_journal_flush(journal);
3540         if (error < 0) {
3541         out:
3542                 jbd2_journal_unlock_updates(journal);
3543                 return error;
3544         }
3545
3546         /* Journal blocked and flushed, clear needs_recovery flag. */
3547         EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3548         error = ext4_commit_super(sb, 1);
3549         if (error)
3550                 goto out;
3551         return 0;
3552 }
3553
3554 /*
3555  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
3556  * flag here, even though the filesystem is not technically dirty yet.
3557  */
3558 static int ext4_unfreeze(struct super_block *sb)
3559 {
3560         if (sb->s_flags & MS_RDONLY)
3561                 return 0;
3562
3563         lock_super(sb);
3564         /* Reset the needs_recovery flag before the fs is unlocked. */
3565         EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3566         ext4_commit_super(sb, 1);
3567         unlock_super(sb);
3568         jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3569         return 0;
3570 }
3571
3572 static int ext4_remount(struct super_block *sb, int *flags, char *data)
3573 {
3574         struct ext4_super_block *es;
3575         struct ext4_sb_info *sbi = EXT4_SB(sb);
3576         ext4_fsblk_t n_blocks_count = 0;
3577         unsigned long old_sb_flags;
3578         struct ext4_mount_options old_opts;
3579         int enable_quota = 0;
3580         ext4_group_t g;
3581         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3582         int err;
3583 #ifdef CONFIG_QUOTA
3584         int i;
3585 #endif
3586
3587         lock_kernel();
3588
3589         /* Store the original options */
3590         lock_super(sb);
3591         old_sb_flags = sb->s_flags;
3592         old_opts.s_mount_opt = sbi->s_mount_opt;
3593         old_opts.s_resuid = sbi->s_resuid;
3594         old_opts.s_resgid = sbi->s_resgid;
3595         old_opts.s_commit_interval = sbi->s_commit_interval;
3596         old_opts.s_min_batch_time = sbi->s_min_batch_time;
3597         old_opts.s_max_batch_time = sbi->s_max_batch_time;
3598 #ifdef CONFIG_QUOTA
3599         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3600         for (i = 0; i < MAXQUOTAS; i++)
3601                 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3602 #endif
3603         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
3604                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
3605
3606         /*
3607          * Allow the "check" option to be passed as a remount option.
3608          */
3609         if (!parse_options(data, sb, NULL, &journal_ioprio,
3610                            &n_blocks_count, 1)) {
3611                 err = -EINVAL;
3612                 goto restore_opts;
3613         }
3614
3615         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
3616                 ext4_abort(sb, __func__, "Abort forced by user");
3617
3618         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3619                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3620
3621         es = sbi->s_es;
3622
3623         if (sbi->s_journal) {
3624                 ext4_init_journal_params(sb, sbi->s_journal);
3625                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3626         }
3627
3628         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3629                 n_blocks_count > ext4_blocks_count(es)) {
3630                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
3631                         err = -EROFS;
3632                         goto restore_opts;
3633                 }
3634
3635                 if (*flags & MS_RDONLY) {
3636                         err = dquot_suspend(sb, -1);
3637                         if (err < 0)
3638                                 goto restore_opts;
3639
3640                         /*
3641                          * First of all, the unconditional stuff we have to do
3642                          * to disable replay of the journal when we next remount
3643                          */
3644                         sb->s_flags |= MS_RDONLY;
3645
3646                         /*
3647                          * OK, test if we are remounting a valid rw partition
3648                          * readonly, and if so set the rdonly flag and then
3649                          * mark the partition as valid again.
3650                          */
3651                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3652                             (sbi->s_mount_state & EXT4_VALID_FS))
3653                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
3654
3655                         if (sbi->s_journal)
3656                                 ext4_mark_recovery_complete(sb, es);
3657                 } else {
3658                         /* Make sure we can mount this feature set readwrite */
3659                         if (!ext4_feature_set_ok(sb, 0)) {
3660                                 err = -EROFS;
3661                                 goto restore_opts;
3662                         }
3663                         /*
3664                          * Make sure the group descriptor checksums
3665                          * are sane.  If they aren't, refuse to remount r/w.
3666                          */
3667                         for (g = 0; g < sbi->s_groups_count; g++) {
3668                                 struct ext4_group_desc *gdp =
3669                                         ext4_get_group_desc(sb, g, NULL);
3670
3671                                 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3672                                         ext4_msg(sb, KERN_ERR,
3673                "ext4_remount: Checksum for group %u failed (%u!=%u)",
3674                 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3675                                                le16_to_cpu(gdp->bg_checksum));
3676                                         err = -EINVAL;
3677                                         goto restore_opts;
3678                                 }
3679                         }
3680
3681                         /*
3682                          * If we have an unprocessed orphan list hanging
3683                          * around from a previously readonly bdev mount,
3684                          * require a full umount/remount for now.
3685                          */
3686                         if (es->s_last_orphan) {
3687                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
3688                                        "remount RDWR because of unprocessed "
3689                                        "orphan inode list.  Please "
3690                                        "umount/remount instead");
3691                                 err = -EINVAL;
3692                                 goto restore_opts;
3693                         }
3694
3695                         /*
3696                          * Mounting a RDONLY partition read-write, so reread
3697                          * and store the current valid flag.  (It may have
3698                          * been changed by e2fsck since we originally mounted
3699                          * the partition.)
3700                          */
3701                         if (sbi->s_journal)
3702                                 ext4_clear_journal_err(sb, es);
3703                         sbi->s_mount_state = le16_to_cpu(es->s_state);
3704                         if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3705                                 goto restore_opts;
3706                         if (!ext4_setup_super(sb, es, 0))
3707                                 sb->s_flags &= ~MS_RDONLY;
3708                         enable_quota = 1;
3709                 }
3710         }
3711         ext4_setup_system_zone(sb);
3712         if (sbi->s_journal == NULL)
3713                 ext4_commit_super(sb, 1);
3714
3715 #ifdef CONFIG_QUOTA
3716         /* Release old quota file names */
3717         for (i = 0; i < MAXQUOTAS; i++)
3718                 if (old_opts.s_qf_names[i] &&
3719                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3720                         kfree(old_opts.s_qf_names[i]);
3721 #endif
3722         unlock_super(sb);
3723         unlock_kernel();
3724         if (enable_quota)
3725                 dquot_resume(sb, -1);
3726         return 0;
3727
3728 restore_opts:
3729         sb->s_flags = old_sb_flags;
3730         sbi->s_mount_opt = old_opts.s_mount_opt;
3731         sbi->s_resuid = old_opts.s_resuid;
3732         sbi->s_resgid = old_opts.s_resgid;
3733         sbi->s_commit_interval = old_opts.s_commit_interval;
3734         sbi->s_min_batch_time = old_opts.s_min_batch_time;
3735         sbi->s_max_batch_time = old_opts.s_max_batch_time;
3736 #ifdef CONFIG_QUOTA
3737         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3738         for (i = 0; i < MAXQUOTAS; i++) {
3739                 if (sbi->s_qf_names[i] &&
3740                     old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3741                         kfree(sbi->s_qf_names[i]);
3742                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3743         }
3744 #endif
3745         unlock_super(sb);
3746         unlock_kernel();
3747         return err;
3748 }
3749
3750 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3751 {
3752         struct super_block *sb = dentry->d_sb;
3753         struct ext4_sb_info *sbi = EXT4_SB(sb);
3754         struct ext4_super_block *es = sbi->s_es;
3755         u64 fsid;
3756
3757         if (test_opt(sb, MINIX_DF)) {
3758                 sbi->s_overhead_last = 0;
3759         } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3760                 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3761                 ext4_fsblk_t overhead = 0;
3762
3763                 /*
3764                  * Compute the overhead (FS structures).  This is constant
3765                  * for a given filesystem unless the number of block groups
3766                  * changes so we cache the previous value until it does.
3767                  */
3768
3769                 /*
3770                  * All of the blocks before first_data_block are
3771                  * overhead
3772                  */
3773                 overhead = le32_to_cpu(es->s_first_data_block);
3774
3775                 /*
3776                  * Add the overhead attributed to the superblock and
3777                  * block group descriptors.  If the sparse superblocks
3778                  * feature is turned on, then not all groups have this.
3779                  */
3780                 for (i = 0; i < ngroups; i++) {
3781                         overhead += ext4_bg_has_super(sb, i) +
3782                                 ext4_bg_num_gdb(sb, i);
3783                         cond_resched();
3784                 }
3785
3786                 /*
3787                  * Every block group has an inode bitmap, a block
3788                  * bitmap, and an inode table.
3789                  */
3790                 overhead += ngroups * (2 + sbi->s_itb_per_group);
3791                 sbi->s_overhead_last = overhead;
3792                 smp_wmb();
3793                 sbi->s_blocks_last = ext4_blocks_count(es);
3794         }
3795
3796         buf->f_type = EXT4_SUPER_MAGIC;
3797         buf->f_bsize = sb->s_blocksize;
3798         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3799         buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3800                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3801         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3802         if (buf->f_bfree < ext4_r_blocks_count(es))
3803                 buf->f_bavail = 0;
3804         buf->f_files = le32_to_cpu(es->s_inodes_count);
3805         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3806         buf->f_namelen = EXT4_NAME_LEN;
3807         fsid = le64_to_cpup((void *)es->s_uuid) ^
3808                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3809         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3810         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3811
3812         return 0;
3813 }
3814
3815 /* Helper function for writing quotas on sync - we need to start transaction
3816  * before quota file is locked for write. Otherwise the are possible deadlocks:
3817  * Process 1                         Process 2
3818  * ext4_create()                     quota_sync()
3819  *   jbd2_journal_start()                  write_dquot()
3820  *   dquot_initialize()                         down(dqio_mutex)
3821  *     down(dqio_mutex)                    jbd2_journal_start()
3822  *
3823  */
3824
3825 #ifdef CONFIG_QUOTA
3826
3827 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3828 {
3829         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3830 }
3831
3832 static int ext4_write_dquot(struct dquot *dquot)
3833 {
3834         int ret, err;
3835         handle_t *handle;
3836         struct inode *inode;
3837
3838         inode = dquot_to_inode(dquot);
3839         handle = ext4_journal_start(inode,
3840                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3841         if (IS_ERR(handle))
3842                 return PTR_ERR(handle);
3843         ret = dquot_commit(dquot);
3844         err = ext4_journal_stop(handle);
3845         if (!ret)
3846                 ret = err;
3847         return ret;
3848 }
3849
3850 static int ext4_acquire_dquot(struct dquot *dquot)
3851 {
3852         int ret, err;
3853         handle_t *handle;
3854
3855         handle = ext4_journal_start(dquot_to_inode(dquot),
3856                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3857         if (IS_ERR(handle))
3858                 return PTR_ERR(handle);
3859         ret = dquot_acquire(dquot);
3860         err = ext4_journal_stop(handle);
3861         if (!ret)
3862                 ret = err;
3863         return ret;
3864 }
3865
3866 static int ext4_release_dquot(struct dquot *dquot)
3867 {
3868         int ret, err;
3869         handle_t *handle;
3870
3871         handle = ext4_journal_start(dquot_to_inode(dquot),
3872                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3873         if (IS_ERR(handle)) {
3874                 /* Release dquot anyway to avoid endless cycle in dqput() */
3875                 dquot_release(dquot);
3876                 return PTR_ERR(handle);
3877         }
3878         ret = dquot_release(dquot);
3879         err = ext4_journal_stop(handle);
3880         if (!ret)
3881                 ret = err;
3882         return ret;
3883 }
3884
3885 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3886 {
3887         /* Are we journaling quotas? */
3888         if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3889             EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3890                 dquot_mark_dquot_dirty(dquot);
3891                 return ext4_write_dquot(dquot);
3892         } else {
3893                 return dquot_mark_dquot_dirty(dquot);
3894         }
3895 }
3896
3897 static int ext4_write_info(struct super_block *sb, int type)
3898 {
3899         int ret, err;
3900         handle_t *handle;
3901
3902         /* Data block + inode block */
3903         handle = ext4_journal_start(sb->s_root->d_inode, 2);
3904         if (IS_ERR(handle))
3905                 return PTR_ERR(handle);
3906         ret = dquot_commit_info(sb, type);
3907         err = ext4_journal_stop(handle);
3908         if (!ret)
3909                 ret = err;
3910         return ret;
3911 }
3912
3913 /*
3914  * Turn on quotas during mount time - we need to find
3915  * the quota file and such...
3916  */
3917 static int ext4_quota_on_mount(struct super_block *sb, int type)
3918 {
3919         return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3920                                   EXT4_SB(sb)->s_jquota_fmt, type);
3921 }
3922
3923 /*
3924  * Standard function to be called on quota_on
3925  */
3926 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3927                          char *name)
3928 {
3929         int err;
3930         struct path path;
3931
3932         if (!test_opt(sb, QUOTA))
3933                 return -EINVAL;
3934
3935         err = kern_path(name, LOOKUP_FOLLOW, &path);
3936         if (err)
3937                 return err;
3938
3939         /* Quotafile not on the same filesystem? */
3940         if (path.mnt->mnt_sb != sb) {
3941                 path_put(&path);
3942                 return -EXDEV;
3943         }
3944         /* Journaling quota? */
3945         if (EXT4_SB(sb)->s_qf_names[type]) {
3946                 /* Quotafile not in fs root? */
3947                 if (path.dentry->d_parent != sb->s_root)
3948                         ext4_msg(sb, KERN_WARNING,
3949                                 "Quota file not on filesystem root. "
3950                                 "Journaled quota will not work");
3951         }
3952
3953         /*
3954          * When we journal data on quota file, we have to flush journal to see
3955          * all updates to the file when we bypass pagecache...
3956          */
3957         if (EXT4_SB(sb)->s_journal &&
3958             ext4_should_journal_data(path.dentry->d_inode)) {
3959                 /*
3960                  * We don't need to lock updates but journal_flush() could
3961                  * otherwise be livelocked...
3962                  */
3963                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3964                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3965                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3966                 if (err) {
3967                         path_put(&path);
3968                         return err;
3969                 }
3970         }
3971
3972         err = vfs_quota_on_path(sb, type, format_id, &path);
3973         path_put(&path);
3974         return err;
3975 }
3976
3977 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3978  * acquiring the locks... As quota files are never truncated and quota code
3979  * itself serializes the operations (and noone else should touch the files)
3980  * we don't have to be afraid of races */
3981 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3982                                size_t len, loff_t off)
3983 {
3984         struct inode *inode = sb_dqopt(sb)->files[type];
3985         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3986         int err = 0;
3987         int offset = off & (sb->s_blocksize - 1);
3988         int tocopy;
3989         size_t toread;
3990         struct buffer_head *bh;
3991         loff_t i_size = i_size_read(inode);
3992
3993         if (off > i_size)
3994                 return 0;
3995         if (off+len > i_size)
3996                 len = i_size-off;
3997         toread = len;
3998         while (toread > 0) {
3999                 tocopy = sb->s_blocksize - offset < toread ?
4000                                 sb->s_blocksize - offset : toread;
4001                 bh = ext4_bread(NULL, inode, blk, 0, &err);
4002                 if (err)
4003                         return err;
4004                 if (!bh)        /* A hole? */
4005                         memset(data, 0, tocopy);
4006                 else
4007                         memcpy(data, bh->b_data+offset, tocopy);
4008                 brelse(bh);
4009                 offset = 0;
4010                 toread -= tocopy;
4011                 data += tocopy;
4012                 blk++;
4013         }
4014         return len;
4015 }
4016
4017 /* Write to quotafile (we know the transaction is already started and has
4018  * enough credits) */
4019 static ssize_t ext4_quota_write(struct super_block *sb, int type,
4020                                 const char *data, size_t len, loff_t off)
4021 {
4022         struct inode *inode = sb_dqopt(sb)->files[type];
4023         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
4024         int err = 0;
4025         int offset = off & (sb->s_blocksize - 1);
4026         int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
4027         struct buffer_head *bh;
4028         handle_t *handle = journal_current_handle();
4029
4030         if (EXT4_SB(sb)->s_journal && !handle) {
4031                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4032                         " cancelled because transaction is not started",
4033                         (unsigned long long)off, (unsigned long long)len);
4034                 return -EIO;
4035         }
4036         /*
4037          * Since we account only one data block in transaction credits,
4038          * then it is impossible to cross a block boundary.
4039          */
4040         if (sb->s_blocksize - offset < len) {
4041                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
4042                         " cancelled because not block aligned",
4043                         (unsigned long long)off, (unsigned long long)len);
4044                 return -EIO;
4045         }
4046
4047         mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
4048         bh = ext4_bread(handle, inode, blk, 1, &err);
4049         if (!bh)
4050                 goto out;
4051         if (journal_quota) {
4052                 err = ext4_journal_get_write_access(handle, bh);
4053                 if (err) {
4054                         brelse(bh);
4055                         goto out;
4056                 }
4057         }
4058         lock_buffer(bh);
4059         memcpy(bh->b_data+offset, data, len);
4060         flush_dcache_page(bh->b_page);
4061         unlock_buffer(bh);
4062         if (journal_quota)
4063                 err = ext4_handle_dirty_metadata(handle, NULL, bh);
4064         else {
4065                 /* Always do at least ordered writes for quotas */
4066                 err = ext4_jbd2_file_inode(handle, inode);
4067                 mark_buffer_dirty(bh);
4068         }
4069         brelse(bh);
4070 out:
4071         if (err) {
4072                 mutex_unlock(&inode->i_mutex);
4073                 return err;
4074         }
4075         if (inode->i_size < off + len) {
4076                 i_size_write(inode, off + len);
4077                 EXT4_I(inode)->i_disksize = inode->i_size;
4078         }
4079         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
4080         ext4_mark_inode_dirty(handle, inode);
4081         mutex_unlock(&inode->i_mutex);
4082         return len;
4083 }
4084
4085 #endif
4086
4087 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
4088                        const char *dev_name, void *data, struct vfsmount *mnt)
4089 {
4090         return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
4091 }
4092
4093 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4094 static struct file_system_type ext2_fs_type = {
4095         .owner          = THIS_MODULE,
4096         .name           = "ext2",
4097         .get_sb         = ext4_get_sb,
4098         .kill_sb        = kill_block_super,
4099         .fs_flags       = FS_REQUIRES_DEV,
4100 };
4101
4102 static inline void register_as_ext2(void)
4103 {
4104         int err = register_filesystem(&ext2_fs_type);
4105         if (err)
4106                 printk(KERN_WARNING
4107                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
4108 }
4109
4110 static inline void unregister_as_ext2(void)
4111 {
4112         unregister_filesystem(&ext2_fs_type);
4113 }
4114 MODULE_ALIAS("ext2");
4115 #else
4116 static inline void register_as_ext2(void) { }
4117 static inline void unregister_as_ext2(void) { }
4118 #endif
4119
4120 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4121 static inline void register_as_ext3(void)
4122 {
4123         int err = register_filesystem(&ext3_fs_type);
4124         if (err)
4125                 printk(KERN_WARNING
4126                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
4127 }
4128
4129 static inline void unregister_as_ext3(void)
4130 {
4131         unregister_filesystem(&ext3_fs_type);
4132 }
4133 MODULE_ALIAS("ext3");
4134 #else
4135 static inline void register_as_ext3(void) { }
4136 static inline void unregister_as_ext3(void) { }
4137 #endif
4138
4139 static struct file_system_type ext4_fs_type = {
4140         .owner          = THIS_MODULE,
4141         .name           = "ext4",
4142         .get_sb         = ext4_get_sb,
4143         .kill_sb        = kill_block_super,
4144         .fs_flags       = FS_REQUIRES_DEV,
4145 };
4146
4147 static int __init init_ext4_fs(void)
4148 {
4149         int err;
4150
4151         err = init_ext4_system_zone();
4152         if (err)
4153                 return err;
4154         ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
4155         if (!ext4_kset)
4156                 goto out4;
4157         ext4_proc_root = proc_mkdir("fs/ext4", NULL);
4158         err = init_ext4_mballoc();
4159         if (err)
4160                 goto out3;
4161
4162         err = init_ext4_xattr();
4163         if (err)
4164                 goto out2;
4165         err = init_inodecache();
4166         if (err)
4167                 goto out1;
4168         register_as_ext2();
4169         register_as_ext3();
4170         err = register_filesystem(&ext4_fs_type);
4171         if (err)
4172                 goto out;
4173         return 0;
4174 out:
4175         unregister_as_ext2();
4176         unregister_as_ext3();
4177         destroy_inodecache();
4178 out1:
4179         exit_ext4_xattr();
4180 out2:
4181         exit_ext4_mballoc();
4182 out3:
4183         remove_proc_entry("fs/ext4", NULL);
4184         kset_unregister(ext4_kset);
4185 out4:
4186         exit_ext4_system_zone();
4187         return err;
4188 }
4189
4190 static void __exit exit_ext4_fs(void)
4191 {
4192         unregister_as_ext2();
4193         unregister_as_ext3();
4194         unregister_filesystem(&ext4_fs_type);
4195         destroy_inodecache();
4196         exit_ext4_xattr();
4197         exit_ext4_mballoc();
4198         remove_proc_entry("fs/ext4", NULL);
4199         kset_unregister(ext4_kset);
4200         exit_ext4_system_zone();
4201 }
4202
4203 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4204 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4205 MODULE_LICENSE("GPL");
4206 module_init(init_ext4_fs)
4207 module_exit(exit_ext4_fs)