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firmware: only allow EDD on x86
[linux-2.6/kvm.git] / fs / ext4 / super.c
blob827bde1f2594b34f4535f6db14a83f53636bfffe
1 /*
2 * linux/fs/ext4/super.c
3 *
4 * Copyright (C) 1992, 1993, 1994, 1995
5 * Remy Card (card@masi.ibp.fr)
6 * Laboratoire MASI - Institut Blaise Pascal
7 * Universite Pierre et Marie Curie (Paris VI)
8 *
9 * from
10 *
11 * linux/fs/minix/inode.c
12 *
13 * Copyright (C) 1991, 1992 Linus Torvalds
14 *
15 * Big-endian to little-endian byte-swapping/bitmaps by
16 * David S. Miller (davem@caip.rutgers.edu), 1995
17 */
18
19 #include <linux/module.h>
20 #include <linux/string.h>
21 #include <linux/fs.h>
22 #include <linux/time.h>
23 #include <linux/vmalloc.h>
24 #include <linux/jbd2.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/parser.h>
29 #include <linux/smp_lock.h>
30 #include <linux/buffer_head.h>
31 #include <linux/exportfs.h>
32 #include <linux/vfs.h>
33 #include <linux/random.h>
34 #include <linux/mount.h>
35 #include <linux/namei.h>
36 #include <linux/quotaops.h>
37 #include <linux/seq_file.h>
38 #include <linux/proc_fs.h>
39 #include <linux/ctype.h>
40 #include <linux/log2.h>
41 #include <linux/crc16.h>
42 #include <asm/uaccess.h>
43
44 #include "ext4.h"
45 #include "ext4_jbd2.h"
46 #include "xattr.h"
47 #include "acl.h"
48 #include "mballoc.h"
49
50 #define CREATE_TRACE_POINTS
51 #include <trace/events/ext4.h>
52
53 struct proc_dir_entry *ext4_proc_root;
54 static struct kset *ext4_kset;
55
56 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
57 unsigned long journal_devnum);
58 static int ext4_commit_super(struct super_block *sb, int sync);
59 static void ext4_mark_recovery_complete(struct super_block *sb,
60 struct ext4_super_block *es);
61 static void ext4_clear_journal_err(struct super_block *sb,
62 struct ext4_super_block *es);
63 static int ext4_sync_fs(struct super_block *sb, int wait);
64 static const char *ext4_decode_error(struct super_block *sb, int errno,
65 char nbuf[16]);
66 static int ext4_remount(struct super_block *sb, int *flags, char *data);
67 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
68 static int ext4_unfreeze(struct super_block *sb);
69 static void ext4_write_super(struct super_block *sb);
70 static int ext4_freeze(struct super_block *sb);
71
72
73 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
74 struct ext4_group_desc *bg)
75 {
76 return le32_to_cpu(bg->bg_block_bitmap_lo) |
77 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
78 (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
79 }
80
81 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
82 struct ext4_group_desc *bg)
83 {
84 return le32_to_cpu(bg->bg_inode_bitmap_lo) |
85 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
86 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
87 }
88
89 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
90 struct ext4_group_desc *bg)
91 {
92 return le32_to_cpu(bg->bg_inode_table_lo) |
93 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
94 (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
95 }
96
97 __u32 ext4_free_blks_count(struct super_block *sb,
98 struct ext4_group_desc *bg)
99 {
100 return le16_to_cpu(bg->bg_free_blocks_count_lo) |
101 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
102 (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
103 }
104
105 __u32 ext4_free_inodes_count(struct super_block *sb,
106 struct ext4_group_desc *bg)
107 {
108 return le16_to_cpu(bg->bg_free_inodes_count_lo) |
109 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
110 (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
111 }
112
113 __u32 ext4_used_dirs_count(struct super_block *sb,
114 struct ext4_group_desc *bg)
115 {
116 return le16_to_cpu(bg->bg_used_dirs_count_lo) |
117 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
118 (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
119 }
120
121 __u32 ext4_itable_unused_count(struct super_block *sb,
122 struct ext4_group_desc *bg)
123 {
124 return le16_to_cpu(bg->bg_itable_unused_lo) |
125 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
126 (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
127 }
128
129 void ext4_block_bitmap_set(struct super_block *sb,
130 struct ext4_group_desc *bg, ext4_fsblk_t blk)
131 {
132 bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
133 if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
134 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
135 }
136
137 void ext4_inode_bitmap_set(struct super_block *sb,
138 struct ext4_group_desc *bg, ext4_fsblk_t blk)
139 {
140 bg->bg_inode_bitmap_lo = cpu_to_le32((u32)blk);
141 if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
142 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
143 }
144
145 void ext4_inode_table_set(struct super_block *sb,
146 struct ext4_group_desc *bg, ext4_fsblk_t blk)
147 {
148 bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
149 if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
150 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
151 }
152
153 void ext4_free_blks_set(struct super_block *sb,
154 struct ext4_group_desc *bg, __u32 count)
155 {
156 bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
157 if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
158 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
159 }
160
161 void ext4_free_inodes_set(struct super_block *sb,
162 struct ext4_group_desc *bg, __u32 count)
163 {
164 bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
165 if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
166 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
167 }
168
169 void ext4_used_dirs_set(struct super_block *sb,
170 struct ext4_group_desc *bg, __u32 count)
171 {
172 bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
173 if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
174 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
175 }
176
177 void ext4_itable_unused_set(struct super_block *sb,
178 struct ext4_group_desc *bg, __u32 count)
179 {
180 bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
181 if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
182 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
183 }
184
185
186 /* Just increment the non-pointer handle value */
187 static handle_t *ext4_get_nojournal(void)
188 {
189 handle_t *handle = current->journal_info;
190 unsigned long ref_cnt = (unsigned long)handle;
191
192 BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
193
194 ref_cnt++;
195 handle = (handle_t *)ref_cnt;
196
197 current->journal_info = handle;
198 return handle;
199 }
200
201
202 /* Decrement the non-pointer handle value */
203 static void ext4_put_nojournal(handle_t *handle)
204 {
205 unsigned long ref_cnt = (unsigned long)handle;
206
207 BUG_ON(ref_cnt == 0);
208
209 ref_cnt--;
210 handle = (handle_t *)ref_cnt;
211
212 current->journal_info = handle;
213 }
214
215 /*
216 * Wrappers for jbd2_journal_start/end.
217 *
218 * The only special thing we need to do here is to make sure that all
219 * journal_end calls result in the superblock being marked dirty, so
220 * that sync() will call the filesystem's write_super callback if
221 * appropriate.
222 */
223 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
224 {
225 journal_t *journal;
226
227 if (sb->s_flags & MS_RDONLY)
228 return ERR_PTR(-EROFS);
229
230 /* Special case here: if the journal has aborted behind our
231 * backs (eg. EIO in the commit thread), then we still need to
232 * take the FS itself readonly cleanly. */
233 journal = EXT4_SB(sb)->s_journal;
234 if (journal) {
235 if (is_journal_aborted(journal)) {
236 ext4_abort(sb, __func__, "Detected aborted journal");
237 return ERR_PTR(-EROFS);
238 }
239 return jbd2_journal_start(journal, nblocks);
240 }
241 return ext4_get_nojournal();
242 }
243
244 /*
245 * The only special thing we need to do here is to make sure that all
246 * jbd2_journal_stop calls result in the superblock being marked dirty, so
247 * that sync() will call the filesystem's write_super callback if
248 * appropriate.
249 */
250 int __ext4_journal_stop(const char *where, handle_t *handle)
251 {
252 struct super_block *sb;
253 int err;
254 int rc;
255
256 if (!ext4_handle_valid(handle)) {
257 ext4_put_nojournal(handle);
258 return 0;
259 }
260 sb = handle->h_transaction->t_journal->j_private;
261 err = handle->h_err;
262 rc = jbd2_journal_stop(handle);
263
264 if (!err)
265 err = rc;
266 if (err)
267 __ext4_std_error(sb, where, err);
268 return err;
269 }
270
271 void ext4_journal_abort_handle(const char *caller, const char *err_fn,
272 struct buffer_head *bh, handle_t *handle, int err)
273 {
274 char nbuf[16];
275 const char *errstr = ext4_decode_error(NULL, err, nbuf);
276
277 BUG_ON(!ext4_handle_valid(handle));
278
279 if (bh)
280 BUFFER_TRACE(bh, "abort");
281
282 if (!handle->h_err)
283 handle->h_err = err;
284
285 if (is_handle_aborted(handle))
286 return;
287
288 printk(KERN_ERR "%s: aborting transaction: %s in %s\n",
289 caller, errstr, err_fn);
290
291 jbd2_journal_abort_handle(handle);
292 }
293
294 /* Deal with the reporting of failure conditions on a filesystem such as
295 * inconsistencies detected or read IO failures.
296 *
297 * On ext2, we can store the error state of the filesystem in the
298 * superblock. That is not possible on ext4, because we may have other
299 * write ordering constraints on the superblock which prevent us from
300 * writing it out straight away; and given that the journal is about to
301 * be aborted, we can't rely on the current, or future, transactions to
302 * write out the superblock safely.
303 *
304 * We'll just use the jbd2_journal_abort() error code to record an error in
305 * the journal instead. On recovery, the journal will compain about
306 * that error until we've noted it down and cleared it.
307 */
308
309 static void ext4_handle_error(struct super_block *sb)
310 {
311 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
312
313 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
314 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
315
316 if (sb->s_flags & MS_RDONLY)
317 return;
318
319 if (!test_opt(sb, ERRORS_CONT)) {
320 journal_t *journal = EXT4_SB(sb)->s_journal;
321
322 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
323 if (journal)
324 jbd2_journal_abort(journal, -EIO);
325 }
326 if (test_opt(sb, ERRORS_RO)) {
327 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
328 sb->s_flags |= MS_RDONLY;
329 }
330 ext4_commit_super(sb, 1);
331 if (test_opt(sb, ERRORS_PANIC))
332 panic("EXT4-fs (device %s): panic forced after error\n",
333 sb->s_id);
334 }
335
336 void ext4_error(struct super_block *sb, const char *function,
337 const char *fmt, ...)
338 {
339 va_list args;
340
341 va_start(args, fmt);
342 printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
343 vprintk(fmt, args);
344 printk("\n");
345 va_end(args);
346
347 ext4_handle_error(sb);
348 }
349
350 static const char *ext4_decode_error(struct super_block *sb, int errno,
351 char nbuf[16])
352 {
353 char *errstr = NULL;
354
355 switch (errno) {
356 case -EIO:
357 errstr = "IO failure";
358 break;
359 case -ENOMEM:
360 errstr = "Out of memory";
361 break;
362 case -EROFS:
363 if (!sb || (EXT4_SB(sb)->s_journal &&
364 EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
365 errstr = "Journal has aborted";
366 else
367 errstr = "Readonly filesystem";
368 break;
369 default:
370 /* If the caller passed in an extra buffer for unknown
371 * errors, textualise them now. Else we just return
372 * NULL. */
373 if (nbuf) {
374 /* Check for truncated error codes... */
375 if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
376 errstr = nbuf;
377 }
378 break;
379 }
380
381 return errstr;
382 }
383
384 /* __ext4_std_error decodes expected errors from journaling functions
385 * automatically and invokes the appropriate error response. */
386
387 void __ext4_std_error(struct super_block *sb, const char *function, int errno)
388 {
389 char nbuf[16];
390 const char *errstr;
391
392 /* Special case: if the error is EROFS, and we're not already
393 * inside a transaction, then there's really no point in logging
394 * an error. */
395 if (errno == -EROFS && journal_current_handle() == NULL &&
396 (sb->s_flags & MS_RDONLY))
397 return;
398
399 errstr = ext4_decode_error(sb, errno, nbuf);
400 printk(KERN_CRIT "EXT4-fs error (device %s) in %s: %s\n",
401 sb->s_id, function, errstr);
402
403 ext4_handle_error(sb);
404 }
405
406 /*
407 * ext4_abort is a much stronger failure handler than ext4_error. The
408 * abort function may be used to deal with unrecoverable failures such
409 * as journal IO errors or ENOMEM at a critical moment in log management.
410 *
411 * We unconditionally force the filesystem into an ABORT|READONLY state,
412 * unless the error response on the fs has been set to panic in which
413 * case we take the easy way out and panic immediately.
414 */
415
416 void ext4_abort(struct super_block *sb, const char *function,
417 const char *fmt, ...)
418 {
419 va_list args;
420
421 va_start(args, fmt);
422 printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
423 vprintk(fmt, args);
424 printk("\n");
425 va_end(args);
426
427 if (test_opt(sb, ERRORS_PANIC))
428 panic("EXT4-fs panic from previous error\n");
429
430 if (sb->s_flags & MS_RDONLY)
431 return;
432
433 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
434 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
435 sb->s_flags |= MS_RDONLY;
436 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
437 if (EXT4_SB(sb)->s_journal)
438 jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
439 }
440
441 void ext4_msg (struct super_block * sb, const char *prefix,
442 const char *fmt, ...)
443 {
444 va_list args;
445
446 va_start(args, fmt);
447 printk("%sEXT4-fs (%s): ", prefix, sb->s_id);
448 vprintk(fmt, args);
449 printk("\n");
450 va_end(args);
451 }
452
453 void ext4_warning(struct super_block *sb, const char *function,
454 const char *fmt, ...)
455 {
456 va_list args;
457
458 va_start(args, fmt);
459 printk(KERN_WARNING "EXT4-fs warning (device %s): %s: ",
460 sb->s_id, function);
461 vprintk(fmt, args);
462 printk("\n");
463 va_end(args);
464 }
465
466 void ext4_grp_locked_error(struct super_block *sb, ext4_group_t grp,
467 const char *function, const char *fmt, ...)
468 __releases(bitlock)
469 __acquires(bitlock)
470 {
471 va_list args;
472 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
473
474 va_start(args, fmt);
475 printk(KERN_CRIT "EXT4-fs error (device %s): %s: ", sb->s_id, function);
476 vprintk(fmt, args);
477 printk("\n");
478 va_end(args);
479
480 if (test_opt(sb, ERRORS_CONT)) {
481 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
482 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
483 ext4_commit_super(sb, 0);
484 return;
485 }
486 ext4_unlock_group(sb, grp);
487 ext4_handle_error(sb);
488 /*
489 * We only get here in the ERRORS_RO case; relocking the group
490 * may be dangerous, but nothing bad will happen since the
491 * filesystem will have already been marked read/only and the
492 * journal has been aborted. We return 1 as a hint to callers
493 * who might what to use the return value from
494 * ext4_grp_locked_error() to distinguish beween the
495 * ERRORS_CONT and ERRORS_RO case, and perhaps return more
496 * aggressively from the ext4 function in question, with a
497 * more appropriate error code.
498 */
499 ext4_lock_group(sb, grp);
500 return;
501 }
502
503 void ext4_update_dynamic_rev(struct super_block *sb)
504 {
505 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
506
507 if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
508 return;
509
510 ext4_warning(sb, __func__,
511 "updating to rev %d because of new feature flag, "
512 "running e2fsck is recommended",
513 EXT4_DYNAMIC_REV);
514
515 es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
516 es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
517 es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
518 /* leave es->s_feature_*compat flags alone */
519 /* es->s_uuid will be set by e2fsck if empty */
520
521 /*
522 * The rest of the superblock fields should be zero, and if not it
523 * means they are likely already in use, so leave them alone. We
524 * can leave it up to e2fsck to clean up any inconsistencies there.
525 */
526 }
527
528 /*
529 * Open the external journal device
530 */
531 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
532 {
533 struct block_device *bdev;
534 char b[BDEVNAME_SIZE];
535
536 bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
537 if (IS_ERR(bdev))
538 goto fail;
539 return bdev;
540
541 fail:
542 ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
543 __bdevname(dev, b), PTR_ERR(bdev));
544 return NULL;
545 }
546
547 /*
548 * Release the journal device
549 */
550 static int ext4_blkdev_put(struct block_device *bdev)
551 {
552 bd_release(bdev);
553 return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
554 }
555
556 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
557 {
558 struct block_device *bdev;
559 int ret = -ENODEV;
560
561 bdev = sbi->journal_bdev;
562 if (bdev) {
563 ret = ext4_blkdev_put(bdev);
564 sbi->journal_bdev = NULL;
565 }
566 return ret;
567 }
568
569 static inline struct inode *orphan_list_entry(struct list_head *l)
570 {
571 return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
572 }
573
574 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
575 {
576 struct list_head *l;
577
578 ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
579 le32_to_cpu(sbi->s_es->s_last_orphan));
580
581 printk(KERN_ERR "sb_info orphan list:\n");
582 list_for_each(l, &sbi->s_orphan) {
583 struct inode *inode = orphan_list_entry(l);
584 printk(KERN_ERR " "
585 "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
586 inode->i_sb->s_id, inode->i_ino, inode,
587 inode->i_mode, inode->i_nlink,
588 NEXT_ORPHAN(inode));
589 }
590 }
591
592 static void ext4_put_super(struct super_block *sb)
593 {
594 struct ext4_sb_info *sbi = EXT4_SB(sb);
595 struct ext4_super_block *es = sbi->s_es;
596 int i, err;
597
598 flush_workqueue(sbi->dio_unwritten_wq);
599 destroy_workqueue(sbi->dio_unwritten_wq);
600
601 lock_super(sb);
602 lock_kernel();
603 if (sb->s_dirt)
604 ext4_commit_super(sb, 1);
605
606 if (sbi->s_journal) {
607 err = jbd2_journal_destroy(sbi->s_journal);
608 sbi->s_journal = NULL;
609 if (err < 0)
610 ext4_abort(sb, __func__,
611 "Couldn't clean up the journal");
612 }
613
614 ext4_release_system_zone(sb);
615 ext4_mb_release(sb);
616 ext4_ext_release(sb);
617 ext4_xattr_put_super(sb);
618
619 if (!(sb->s_flags & MS_RDONLY)) {
620 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
621 es->s_state = cpu_to_le16(sbi->s_mount_state);
622 ext4_commit_super(sb, 1);
623 }
624 if (sbi->s_proc) {
625 remove_proc_entry(sb->s_id, ext4_proc_root);
626 }
627 kobject_del(&sbi->s_kobj);
628
629 for (i = 0; i < sbi->s_gdb_count; i++)
630 brelse(sbi->s_group_desc[i]);
631 kfree(sbi->s_group_desc);
632 if (is_vmalloc_addr(sbi->s_flex_groups))
633 vfree(sbi->s_flex_groups);
634 else
635 kfree(sbi->s_flex_groups);
636 percpu_counter_destroy(&sbi->s_freeblocks_counter);
637 percpu_counter_destroy(&sbi->s_freeinodes_counter);
638 percpu_counter_destroy(&sbi->s_dirs_counter);
639 percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
640 brelse(sbi->s_sbh);
641 #ifdef CONFIG_QUOTA
642 for (i = 0; i < MAXQUOTAS; i++)
643 kfree(sbi->s_qf_names[i]);
644 #endif
645
646 /* Debugging code just in case the in-memory inode orphan list
647 * isn't empty. The on-disk one can be non-empty if we've
648 * detected an error and taken the fs readonly, but the
649 * in-memory list had better be clean by this point. */
650 if (!list_empty(&sbi->s_orphan))
651 dump_orphan_list(sb, sbi);
652 J_ASSERT(list_empty(&sbi->s_orphan));
653
654 invalidate_bdev(sb->s_bdev);
655 if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
656 /*
657 * Invalidate the journal device's buffers. We don't want them
658 * floating about in memory - the physical journal device may
659 * hotswapped, and it breaks the `ro-after' testing code.
660 */
661 sync_blockdev(sbi->journal_bdev);
662 invalidate_bdev(sbi->journal_bdev);
663 ext4_blkdev_remove(sbi);
664 }
665 sb->s_fs_info = NULL;
666 /*
667 * Now that we are completely done shutting down the
668 * superblock, we need to actually destroy the kobject.
669 */
670 unlock_kernel();
671 unlock_super(sb);
672 kobject_put(&sbi->s_kobj);
673 wait_for_completion(&sbi->s_kobj_unregister);
674 kfree(sbi->s_blockgroup_lock);
675 kfree(sbi);
676 }
677
678 static struct kmem_cache *ext4_inode_cachep;
679
680 /*
681 * Called inside transaction, so use GFP_NOFS
682 */
683 static struct inode *ext4_alloc_inode(struct super_block *sb)
684 {
685 struct ext4_inode_info *ei;
686
687 ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
688 if (!ei)
689 return NULL;
690
691 ei->vfs_inode.i_version = 1;
692 ei->vfs_inode.i_data.writeback_index = 0;
693 memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
694 INIT_LIST_HEAD(&ei->i_prealloc_list);
695 spin_lock_init(&ei->i_prealloc_lock);
696 /*
697 * Note: We can be called before EXT4_SB(sb)->s_journal is set,
698 * therefore it can be null here. Don't check it, just initialize
699 * jinode.
700 */
701 jbd2_journal_init_jbd_inode(&ei->jinode, &ei->vfs_inode);
702 ei->i_reserved_data_blocks = 0;
703 ei->i_reserved_meta_blocks = 0;
704 ei->i_allocated_meta_blocks = 0;
705 ei->i_delalloc_reserved_flag = 0;
706 spin_lock_init(&(ei->i_block_reservation_lock));
707 INIT_LIST_HEAD(&ei->i_aio_dio_complete_list);
708 ei->cur_aio_dio = NULL;
709 ei->i_sync_tid = 0;
710 ei->i_datasync_tid = 0;
711
712 return &ei->vfs_inode;
713 }
714
715 static void ext4_destroy_inode(struct inode *inode)
716 {
717 if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
718 ext4_msg(inode->i_sb, KERN_ERR,
719 "Inode %lu (%p): orphan list check failed!",
720 inode->i_ino, EXT4_I(inode));
721 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
722 EXT4_I(inode), sizeof(struct ext4_inode_info),
723 true);
724 dump_stack();
725 }
726 kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
727 }
728
729 static void init_once(void *foo)
730 {
731 struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
732
733 INIT_LIST_HEAD(&ei->i_orphan);
734 #ifdef CONFIG_EXT4_FS_XATTR
735 init_rwsem(&ei->xattr_sem);
736 #endif
737 init_rwsem(&ei->i_data_sem);
738 inode_init_once(&ei->vfs_inode);
739 }
740
741 static int init_inodecache(void)
742 {
743 ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
744 sizeof(struct ext4_inode_info),
745 0, (SLAB_RECLAIM_ACCOUNT|
746 SLAB_MEM_SPREAD),
747 init_once);
748 if (ext4_inode_cachep == NULL)
749 return -ENOMEM;
750 return 0;
751 }
752
753 static void destroy_inodecache(void)
754 {
755 kmem_cache_destroy(ext4_inode_cachep);
756 }
757
758 static void ext4_clear_inode(struct inode *inode)
759 {
760 ext4_discard_preallocations(inode);
761 if (EXT4_JOURNAL(inode))
762 jbd2_journal_release_jbd_inode(EXT4_SB(inode->i_sb)->s_journal,
763 &EXT4_I(inode)->jinode);
764 }
765
766 static inline void ext4_show_quota_options(struct seq_file *seq,
767 struct super_block *sb)
768 {
769 #if defined(CONFIG_QUOTA)
770 struct ext4_sb_info *sbi = EXT4_SB(sb);
771
772 if (sbi->s_jquota_fmt) {
773 char *fmtname = "";
774
775 switch (sbi->s_jquota_fmt) {
776 case QFMT_VFS_OLD:
777 fmtname = "vfsold";
778 break;
779 case QFMT_VFS_V0:
780 fmtname = "vfsv0";
781 break;
782 case QFMT_VFS_V1:
783 fmtname = "vfsv1";
784 break;
785 }
786 seq_printf(seq, ",jqfmt=%s", fmtname);
787 }
788
789 if (sbi->s_qf_names[USRQUOTA])
790 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
791
792 if (sbi->s_qf_names[GRPQUOTA])
793 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
794
795 if (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA)
796 seq_puts(seq, ",usrquota");
797
798 if (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)
799 seq_puts(seq, ",grpquota");
800 #endif
801 }
802
803 /*
804 * Show an option if
805 * - it's set to a non-default value OR
806 * - if the per-sb default is different from the global default
807 */
808 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
809 {
810 int def_errors;
811 unsigned long def_mount_opts;
812 struct super_block *sb = vfs->mnt_sb;
813 struct ext4_sb_info *sbi = EXT4_SB(sb);
814 struct ext4_super_block *es = sbi->s_es;
815
816 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
817 def_errors = le16_to_cpu(es->s_errors);
818
819 if (sbi->s_sb_block != 1)
820 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
821 if (test_opt(sb, MINIX_DF))
822 seq_puts(seq, ",minixdf");
823 if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
824 seq_puts(seq, ",grpid");
825 if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
826 seq_puts(seq, ",nogrpid");
827 if (sbi->s_resuid != EXT4_DEF_RESUID ||
828 le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
829 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
830 }
831 if (sbi->s_resgid != EXT4_DEF_RESGID ||
832 le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
833 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
834 }
835 if (test_opt(sb, ERRORS_RO)) {
836 if (def_errors == EXT4_ERRORS_PANIC ||
837 def_errors == EXT4_ERRORS_CONTINUE) {
838 seq_puts(seq, ",errors=remount-ro");
839 }
840 }
841 if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
842 seq_puts(seq, ",errors=continue");
843 if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
844 seq_puts(seq, ",errors=panic");
845 if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
846 seq_puts(seq, ",nouid32");
847 if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
848 seq_puts(seq, ",debug");
849 if (test_opt(sb, OLDALLOC))
850 seq_puts(seq, ",oldalloc");
851 #ifdef CONFIG_EXT4_FS_XATTR
852 if (test_opt(sb, XATTR_USER) &&
853 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
854 seq_puts(seq, ",user_xattr");
855 if (!test_opt(sb, XATTR_USER) &&
856 (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
857 seq_puts(seq, ",nouser_xattr");
858 }
859 #endif
860 #ifdef CONFIG_EXT4_FS_POSIX_ACL
861 if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
862 seq_puts(seq, ",acl");
863 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
864 seq_puts(seq, ",noacl");
865 #endif
866 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
867 seq_printf(seq, ",commit=%u",
868 (unsigned) (sbi->s_commit_interval / HZ));
869 }
870 if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
871 seq_printf(seq, ",min_batch_time=%u",
872 (unsigned) sbi->s_min_batch_time);
873 }
874 if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
875 seq_printf(seq, ",max_batch_time=%u",
876 (unsigned) sbi->s_min_batch_time);
877 }
878
879 /*
880 * We're changing the default of barrier mount option, so
881 * let's always display its mount state so it's clear what its
882 * status is.
883 */
884 seq_puts(seq, ",barrier=");
885 seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
886 if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
887 seq_puts(seq, ",journal_async_commit");
888 if (test_opt(sb, NOBH))
889 seq_puts(seq, ",nobh");
890 if (test_opt(sb, I_VERSION))
891 seq_puts(seq, ",i_version");
892 if (!test_opt(sb, DELALLOC))
893 seq_puts(seq, ",nodelalloc");
894
895
896 if (sbi->s_stripe)
897 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
898 /*
899 * journal mode get enabled in different ways
900 * So just print the value even if we didn't specify it
901 */
902 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
903 seq_puts(seq, ",data=journal");
904 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
905 seq_puts(seq, ",data=ordered");
906 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
907 seq_puts(seq, ",data=writeback");
908
909 if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
910 seq_printf(seq, ",inode_readahead_blks=%u",
911 sbi->s_inode_readahead_blks);
912
913 if (test_opt(sb, DATA_ERR_ABORT))
914 seq_puts(seq, ",data_err=abort");
915
916 if (test_opt(sb, NO_AUTO_DA_ALLOC))
917 seq_puts(seq, ",noauto_da_alloc");
918
919 if (test_opt(sb, DISCARD))
920 seq_puts(seq, ",discard");
921
922 if (test_opt(sb, NOLOAD))
923 seq_puts(seq, ",norecovery");
924
925 ext4_show_quota_options(seq, sb);
926
927 return 0;
928 }
929
930 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
931 u64 ino, u32 generation)
932 {
933 struct inode *inode;
934
935 if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
936 return ERR_PTR(-ESTALE);
937 if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
938 return ERR_PTR(-ESTALE);
939
940 /* iget isn't really right if the inode is currently unallocated!!
941 *
942 * ext4_read_inode will return a bad_inode if the inode had been
943 * deleted, so we should be safe.
944 *
945 * Currently we don't know the generation for parent directory, so
946 * a generation of 0 means "accept any"
947 */
948 inode = ext4_iget(sb, ino);
949 if (IS_ERR(inode))
950 return ERR_CAST(inode);
951 if (generation && inode->i_generation != generation) {
952 iput(inode);
953 return ERR_PTR(-ESTALE);
954 }
955
956 return inode;
957 }
958
959 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
960 int fh_len, int fh_type)
961 {
962 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
963 ext4_nfs_get_inode);
964 }
965
966 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
967 int fh_len, int fh_type)
968 {
969 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
970 ext4_nfs_get_inode);
971 }
972
973 /*
974 * Try to release metadata pages (indirect blocks, directories) which are
975 * mapped via the block device. Since these pages could have journal heads
976 * which would prevent try_to_free_buffers() from freeing them, we must use
977 * jbd2 layer's try_to_free_buffers() function to release them.
978 */
979 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
980 gfp_t wait)
981 {
982 journal_t *journal = EXT4_SB(sb)->s_journal;
983
984 WARN_ON(PageChecked(page));
985 if (!page_has_buffers(page))
986 return 0;
987 if (journal)
988 return jbd2_journal_try_to_free_buffers(journal, page,
989 wait & ~__GFP_WAIT);
990 return try_to_free_buffers(page);
991 }
992
993 #ifdef CONFIG_QUOTA
994 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
995 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
996
997 static int ext4_write_dquot(struct dquot *dquot);
998 static int ext4_acquire_dquot(struct dquot *dquot);
999 static int ext4_release_dquot(struct dquot *dquot);
1000 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1001 static int ext4_write_info(struct super_block *sb, int type);
1002 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1003 char *path, int remount);
1004 static int ext4_quota_on_mount(struct super_block *sb, int type);
1005 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1006 size_t len, loff_t off);
1007 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1008 const char *data, size_t len, loff_t off);
1009
1010 static const struct dquot_operations ext4_quota_operations = {
1011 .initialize = dquot_initialize,
1012 .drop = dquot_drop,
1013 .alloc_space = dquot_alloc_space,
1014 .reserve_space = dquot_reserve_space,
1015 .claim_space = dquot_claim_space,
1016 .release_rsv = dquot_release_reserved_space,
1017 .get_reserved_space = ext4_get_reserved_space,
1018 .alloc_inode = dquot_alloc_inode,
1019 .free_space = dquot_free_space,
1020 .free_inode = dquot_free_inode,
1021 .transfer = dquot_transfer,
1022 .write_dquot = ext4_write_dquot,
1023 .acquire_dquot = ext4_acquire_dquot,
1024 .release_dquot = ext4_release_dquot,
1025 .mark_dirty = ext4_mark_dquot_dirty,
1026 .write_info = ext4_write_info,
1027 .alloc_dquot = dquot_alloc,
1028 .destroy_dquot = dquot_destroy,
1029 };
1030
1031 static const struct quotactl_ops ext4_qctl_operations = {
1032 .quota_on = ext4_quota_on,
1033 .quota_off = vfs_quota_off,
1034 .quota_sync = vfs_quota_sync,
1035 .get_info = vfs_get_dqinfo,
1036 .set_info = vfs_set_dqinfo,
1037 .get_dqblk = vfs_get_dqblk,
1038 .set_dqblk = vfs_set_dqblk
1039 };
1040 #endif
1041
1042 static const struct super_operations ext4_sops = {
1043 .alloc_inode = ext4_alloc_inode,
1044 .destroy_inode = ext4_destroy_inode,
1045 .write_inode = ext4_write_inode,
1046 .dirty_inode = ext4_dirty_inode,
1047 .delete_inode = ext4_delete_inode,
1048 .put_super = ext4_put_super,
1049 .sync_fs = ext4_sync_fs,
1050 .freeze_fs = ext4_freeze,
1051 .unfreeze_fs = ext4_unfreeze,
1052 .statfs = ext4_statfs,
1053 .remount_fs = ext4_remount,
1054 .clear_inode = ext4_clear_inode,
1055 .show_options = ext4_show_options,
1056 #ifdef CONFIG_QUOTA
1057 .quota_read = ext4_quota_read,
1058 .quota_write = ext4_quota_write,
1059 #endif
1060 .bdev_try_to_free_page = bdev_try_to_free_page,
1061 };
1062
1063 static const struct super_operations ext4_nojournal_sops = {
1064 .alloc_inode = ext4_alloc_inode,
1065 .destroy_inode = ext4_destroy_inode,
1066 .write_inode = ext4_write_inode,
1067 .dirty_inode = ext4_dirty_inode,
1068 .delete_inode = ext4_delete_inode,
1069 .write_super = ext4_write_super,
1070 .put_super = ext4_put_super,
1071 .statfs = ext4_statfs,
1072 .remount_fs = ext4_remount,
1073 .clear_inode = ext4_clear_inode,
1074 .show_options = ext4_show_options,
1075 #ifdef CONFIG_QUOTA
1076 .quota_read = ext4_quota_read,
1077 .quota_write = ext4_quota_write,
1078 #endif
1079 .bdev_try_to_free_page = bdev_try_to_free_page,
1080 };
1081
1082 static const struct export_operations ext4_export_ops = {
1083 .fh_to_dentry = ext4_fh_to_dentry,
1084 .fh_to_parent = ext4_fh_to_parent,
1085 .get_parent = ext4_get_parent,
1086 };
1087
1088 enum {
1089 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1090 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1091 Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1092 Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1093 Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1094 Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1095 Opt_journal_update, Opt_journal_dev,
1096 Opt_journal_checksum, Opt_journal_async_commit,
1097 Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1098 Opt_data_err_abort, Opt_data_err_ignore,
1099 Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1100 Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1101 Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1102 Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1103 Opt_stripe, Opt_delalloc, Opt_nodelalloc,
1104 Opt_block_validity, Opt_noblock_validity,
1105 Opt_inode_readahead_blks, Opt_journal_ioprio,
1106 Opt_discard, Opt_nodiscard,
1107 };
1108
1109 static const match_table_t tokens = {
1110 {Opt_bsd_df, "bsddf"},
1111 {Opt_minix_df, "minixdf"},
1112 {Opt_grpid, "grpid"},
1113 {Opt_grpid, "bsdgroups"},
1114 {Opt_nogrpid, "nogrpid"},
1115 {Opt_nogrpid, "sysvgroups"},
1116 {Opt_resgid, "resgid=%u"},
1117 {Opt_resuid, "resuid=%u"},
1118 {Opt_sb, "sb=%u"},
1119 {Opt_err_cont, "errors=continue"},
1120 {Opt_err_panic, "errors=panic"},
1121 {Opt_err_ro, "errors=remount-ro"},
1122 {Opt_nouid32, "nouid32"},
1123 {Opt_debug, "debug"},
1124 {Opt_oldalloc, "oldalloc"},
1125 {Opt_orlov, "orlov"},
1126 {Opt_user_xattr, "user_xattr"},
1127 {Opt_nouser_xattr, "nouser_xattr"},
1128 {Opt_acl, "acl"},
1129 {Opt_noacl, "noacl"},
1130 {Opt_noload, "noload"},
1131 {Opt_noload, "norecovery"},
1132 {Opt_nobh, "nobh"},
1133 {Opt_bh, "bh"},
1134 {Opt_commit, "commit=%u"},
1135 {Opt_min_batch_time, "min_batch_time=%u"},
1136 {Opt_max_batch_time, "max_batch_time=%u"},
1137 {Opt_journal_update, "journal=update"},
1138 {Opt_journal_dev, "journal_dev=%u"},
1139 {Opt_journal_checksum, "journal_checksum"},
1140 {Opt_journal_async_commit, "journal_async_commit"},
1141 {Opt_abort, "abort"},
1142 {Opt_data_journal, "data=journal"},
1143 {Opt_data_ordered, "data=ordered"},
1144 {Opt_data_writeback, "data=writeback"},
1145 {Opt_data_err_abort, "data_err=abort"},
1146 {Opt_data_err_ignore, "data_err=ignore"},
1147 {Opt_offusrjquota, "usrjquota="},
1148 {Opt_usrjquota, "usrjquota=%s"},
1149 {Opt_offgrpjquota, "grpjquota="},
1150 {Opt_grpjquota, "grpjquota=%s"},
1151 {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1152 {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1153 {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1154 {Opt_grpquota, "grpquota"},
1155 {Opt_noquota, "noquota"},
1156 {Opt_quota, "quota"},
1157 {Opt_usrquota, "usrquota"},
1158 {Opt_barrier, "barrier=%u"},
1159 {Opt_barrier, "barrier"},
1160 {Opt_nobarrier, "nobarrier"},
1161 {Opt_i_version, "i_version"},
1162 {Opt_stripe, "stripe=%u"},
1163 {Opt_resize, "resize"},
1164 {Opt_delalloc, "delalloc"},
1165 {Opt_nodelalloc, "nodelalloc"},
1166 {Opt_block_validity, "block_validity"},
1167 {Opt_noblock_validity, "noblock_validity"},
1168 {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1169 {Opt_journal_ioprio, "journal_ioprio=%u"},
1170 {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1171 {Opt_auto_da_alloc, "auto_da_alloc"},
1172 {Opt_noauto_da_alloc, "noauto_da_alloc"},
1173 {Opt_discard, "discard"},
1174 {Opt_nodiscard, "nodiscard"},
1175 {Opt_err, NULL},
1176 };
1177
1178 static ext4_fsblk_t get_sb_block(void **data)
1179 {
1180 ext4_fsblk_t sb_block;
1181 char *options = (char *) *data;
1182
1183 if (!options || strncmp(options, "sb=", 3) != 0)
1184 return 1; /* Default location */
1185
1186 options += 3;
1187 /* TODO: use simple_strtoll with >32bit ext4 */
1188 sb_block = simple_strtoul(options, &options, 0);
1189 if (*options && *options != ',') {
1190 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1191 (char *) *data);
1192 return 1;
1193 }
1194 if (*options == ',')
1195 options++;
1196 *data = (void *) options;
1197
1198 return sb_block;
1199 }
1200
1201 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1202
1203 static int parse_options(char *options, struct super_block *sb,
1204 unsigned long *journal_devnum,
1205 unsigned int *journal_ioprio,
1206 ext4_fsblk_t *n_blocks_count, int is_remount)
1207 {
1208 struct ext4_sb_info *sbi = EXT4_SB(sb);
1209 char *p;
1210 substring_t args[MAX_OPT_ARGS];
1211 int data_opt = 0;
1212 int option;
1213 #ifdef CONFIG_QUOTA
1214 int qtype, qfmt;
1215 char *qname;
1216 #endif
1217
1218 if (!options)
1219 return 1;
1220
1221 while ((p = strsep(&options, ",")) != NULL) {
1222 int token;
1223 if (!*p)
1224 continue;
1225
1226 token = match_token(p, tokens, args);
1227 switch (token) {
1228 case Opt_bsd_df:
1229 clear_opt(sbi->s_mount_opt, MINIX_DF);
1230 break;
1231 case Opt_minix_df:
1232 set_opt(sbi->s_mount_opt, MINIX_DF);
1233 break;
1234 case Opt_grpid:
1235 set_opt(sbi->s_mount_opt, GRPID);
1236 break;
1237 case Opt_nogrpid:
1238 clear_opt(sbi->s_mount_opt, GRPID);
1239 break;
1240 case Opt_resuid:
1241 if (match_int(&args[0], &option))
1242 return 0;
1243 sbi->s_resuid = option;
1244 break;
1245 case Opt_resgid:
1246 if (match_int(&args[0], &option))
1247 return 0;
1248 sbi->s_resgid = option;
1249 break;
1250 case Opt_sb:
1251 /* handled by get_sb_block() instead of here */
1252 /* *sb_block = match_int(&args[0]); */
1253 break;
1254 case Opt_err_panic:
1255 clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1256 clear_opt(sbi->s_mount_opt, ERRORS_RO);
1257 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
1258 break;
1259 case Opt_err_ro:
1260 clear_opt(sbi->s_mount_opt, ERRORS_CONT);
1261 clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1262 set_opt(sbi->s_mount_opt, ERRORS_RO);
1263 break;
1264 case Opt_err_cont:
1265 clear_opt(sbi->s_mount_opt, ERRORS_RO);
1266 clear_opt(sbi->s_mount_opt, ERRORS_PANIC);
1267 set_opt(sbi->s_mount_opt, ERRORS_CONT);
1268 break;
1269 case Opt_nouid32:
1270 set_opt(sbi->s_mount_opt, NO_UID32);
1271 break;
1272 case Opt_debug:
1273 set_opt(sbi->s_mount_opt, DEBUG);
1274 break;
1275 case Opt_oldalloc:
1276 set_opt(sbi->s_mount_opt, OLDALLOC);
1277 break;
1278 case Opt_orlov:
1279 clear_opt(sbi->s_mount_opt, OLDALLOC);
1280 break;
1281 #ifdef CONFIG_EXT4_FS_XATTR
1282 case Opt_user_xattr:
1283 set_opt(sbi->s_mount_opt, XATTR_USER);
1284 break;
1285 case Opt_nouser_xattr:
1286 clear_opt(sbi->s_mount_opt, XATTR_USER);
1287 break;
1288 #else
1289 case Opt_user_xattr:
1290 case Opt_nouser_xattr:
1291 ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1292 break;
1293 #endif
1294 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1295 case Opt_acl:
1296 set_opt(sbi->s_mount_opt, POSIX_ACL);
1297 break;
1298 case Opt_noacl:
1299 clear_opt(sbi->s_mount_opt, POSIX_ACL);
1300 break;
1301 #else
1302 case Opt_acl:
1303 case Opt_noacl:
1304 ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1305 break;
1306 #endif
1307 case Opt_journal_update:
1308 /* @@@ FIXME */
1309 /* Eventually we will want to be able to create
1310 a journal file here. For now, only allow the
1311 user to specify an existing inode to be the
1312 journal file. */
1313 if (is_remount) {
1314 ext4_msg(sb, KERN_ERR,
1315 "Cannot specify journal on remount");
1316 return 0;
1317 }
1318 set_opt(sbi->s_mount_opt, UPDATE_JOURNAL);
1319 break;
1320 case Opt_journal_dev:
1321 if (is_remount) {
1322 ext4_msg(sb, KERN_ERR,
1323 "Cannot specify journal on remount");
1324 return 0;
1325 }
1326 if (match_int(&args[0], &option))
1327 return 0;
1328 *journal_devnum = option;
1329 break;
1330 case Opt_journal_checksum:
1331 set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1332 break;
1333 case Opt_journal_async_commit:
1334 set_opt(sbi->s_mount_opt, JOURNAL_ASYNC_COMMIT);
1335 set_opt(sbi->s_mount_opt, JOURNAL_CHECKSUM);
1336 break;
1337 case Opt_noload:
1338 set_opt(sbi->s_mount_opt, NOLOAD);
1339 break;
1340 case Opt_commit:
1341 if (match_int(&args[0], &option))
1342 return 0;
1343 if (option < 0)
1344 return 0;
1345 if (option == 0)
1346 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1347 sbi->s_commit_interval = HZ * option;
1348 break;
1349 case Opt_max_batch_time:
1350 if (match_int(&args[0], &option))
1351 return 0;
1352 if (option < 0)
1353 return 0;
1354 if (option == 0)
1355 option = EXT4_DEF_MAX_BATCH_TIME;
1356 sbi->s_max_batch_time = option;
1357 break;
1358 case Opt_min_batch_time:
1359 if (match_int(&args[0], &option))
1360 return 0;
1361 if (option < 0)
1362 return 0;
1363 sbi->s_min_batch_time = option;
1364 break;
1365 case Opt_data_journal:
1366 data_opt = EXT4_MOUNT_JOURNAL_DATA;
1367 goto datacheck;
1368 case Opt_data_ordered:
1369 data_opt = EXT4_MOUNT_ORDERED_DATA;
1370 goto datacheck;
1371 case Opt_data_writeback:
1372 data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1373 datacheck:
1374 if (is_remount) {
1375 if ((sbi->s_mount_opt & EXT4_MOUNT_DATA_FLAGS)
1376 != data_opt) {
1377 ext4_msg(sb, KERN_ERR,
1378 "Cannot change data mode on remount");
1379 return 0;
1380 }
1381 } else {
1382 sbi->s_mount_opt &= ~EXT4_MOUNT_DATA_FLAGS;
1383 sbi->s_mount_opt |= data_opt;
1384 }
1385 break;
1386 case Opt_data_err_abort:
1387 set_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1388 break;
1389 case Opt_data_err_ignore:
1390 clear_opt(sbi->s_mount_opt, DATA_ERR_ABORT);
1391 break;
1392 #ifdef CONFIG_QUOTA
1393 case Opt_usrjquota:
1394 qtype = USRQUOTA;
1395 goto set_qf_name;
1396 case Opt_grpjquota:
1397 qtype = GRPQUOTA;
1398 set_qf_name:
1399 if (sb_any_quota_loaded(sb) &&
1400 !sbi->s_qf_names[qtype]) {
1401 ext4_msg(sb, KERN_ERR,
1402 "Cannot change journaled "
1403 "quota options when quota turned on");
1404 return 0;
1405 }
1406 qname = match_strdup(&args[0]);
1407 if (!qname) {
1408 ext4_msg(sb, KERN_ERR,
1409 "Not enough memory for "
1410 "storing quotafile name");
1411 return 0;
1412 }
1413 if (sbi->s_qf_names[qtype] &&
1414 strcmp(sbi->s_qf_names[qtype], qname)) {
1415 ext4_msg(sb, KERN_ERR,
1416 "%s quota file already "
1417 "specified", QTYPE2NAME(qtype));
1418 kfree(qname);
1419 return 0;
1420 }
1421 sbi->s_qf_names[qtype] = qname;
1422 if (strchr(sbi->s_qf_names[qtype], '/')) {
1423 ext4_msg(sb, KERN_ERR,
1424 "quotafile must be on "
1425 "filesystem root");
1426 kfree(sbi->s_qf_names[qtype]);
1427 sbi->s_qf_names[qtype] = NULL;
1428 return 0;
1429 }
1430 set_opt(sbi->s_mount_opt, QUOTA);
1431 break;
1432 case Opt_offusrjquota:
1433 qtype = USRQUOTA;
1434 goto clear_qf_name;
1435 case Opt_offgrpjquota:
1436 qtype = GRPQUOTA;
1437 clear_qf_name:
1438 if (sb_any_quota_loaded(sb) &&
1439 sbi->s_qf_names[qtype]) {
1440 ext4_msg(sb, KERN_ERR, "Cannot change "
1441 "journaled quota options when "
1442 "quota turned on");
1443 return 0;
1444 }
1445 /*
1446 * The space will be released later when all options
1447 * are confirmed to be correct
1448 */
1449 sbi->s_qf_names[qtype] = NULL;
1450 break;
1451 case Opt_jqfmt_vfsold:
1452 qfmt = QFMT_VFS_OLD;
1453 goto set_qf_format;
1454 case Opt_jqfmt_vfsv0:
1455 qfmt = QFMT_VFS_V0;
1456 goto set_qf_format;
1457 case Opt_jqfmt_vfsv1:
1458 qfmt = QFMT_VFS_V1;
1459 set_qf_format:
1460 if (sb_any_quota_loaded(sb) &&
1461 sbi->s_jquota_fmt != qfmt) {
1462 ext4_msg(sb, KERN_ERR, "Cannot change "
1463 "journaled quota options when "
1464 "quota turned on");
1465 return 0;
1466 }
1467 sbi->s_jquota_fmt = qfmt;
1468 break;
1469 case Opt_quota:
1470 case Opt_usrquota:
1471 set_opt(sbi->s_mount_opt, QUOTA);
1472 set_opt(sbi->s_mount_opt, USRQUOTA);
1473 break;
1474 case Opt_grpquota:
1475 set_opt(sbi->s_mount_opt, QUOTA);
1476 set_opt(sbi->s_mount_opt, GRPQUOTA);
1477 break;
1478 case Opt_noquota:
1479 if (sb_any_quota_loaded(sb)) {
1480 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1481 "options when quota turned on");
1482 return 0;
1483 }
1484 clear_opt(sbi->s_mount_opt, QUOTA);
1485 clear_opt(sbi->s_mount_opt, USRQUOTA);
1486 clear_opt(sbi->s_mount_opt, GRPQUOTA);
1487 break;
1488 #else
1489 case Opt_quota:
1490 case Opt_usrquota:
1491 case Opt_grpquota:
1492 ext4_msg(sb, KERN_ERR,
1493 "quota options not supported");
1494 break;
1495 case Opt_usrjquota:
1496 case Opt_grpjquota:
1497 case Opt_offusrjquota:
1498 case Opt_offgrpjquota:
1499 case Opt_jqfmt_vfsold:
1500 case Opt_jqfmt_vfsv0:
1501 case Opt_jqfmt_vfsv1:
1502 ext4_msg(sb, KERN_ERR,
1503 "journaled quota options not supported");
1504 break;
1505 case Opt_noquota:
1506 break;
1507 #endif
1508 case Opt_abort:
1509 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1510 break;
1511 case Opt_nobarrier:
1512 clear_opt(sbi->s_mount_opt, BARRIER);
1513 break;
1514 case Opt_barrier:
1515 if (match_int(&args[0], &option)) {
1516 set_opt(sbi->s_mount_opt, BARRIER);
1517 break;
1518 }
1519 if (option)
1520 set_opt(sbi->s_mount_opt, BARRIER);
1521 else
1522 clear_opt(sbi->s_mount_opt, BARRIER);
1523 break;
1524 case Opt_ignore:
1525 break;
1526 case Opt_resize:
1527 if (!is_remount) {
1528 ext4_msg(sb, KERN_ERR,
1529 "resize option only available "
1530 "for remount");
1531 return 0;
1532 }
1533 if (match_int(&args[0], &option) != 0)
1534 return 0;
1535 *n_blocks_count = option;
1536 break;
1537 case Opt_nobh:
1538 set_opt(sbi->s_mount_opt, NOBH);
1539 break;
1540 case Opt_bh:
1541 clear_opt(sbi->s_mount_opt, NOBH);
1542 break;
1543 case Opt_i_version:
1544 set_opt(sbi->s_mount_opt, I_VERSION);
1545 sb->s_flags |= MS_I_VERSION;
1546 break;
1547 case Opt_nodelalloc:
1548 clear_opt(sbi->s_mount_opt, DELALLOC);
1549 break;
1550 case Opt_stripe:
1551 if (match_int(&args[0], &option))
1552 return 0;
1553 if (option < 0)
1554 return 0;
1555 sbi->s_stripe = option;
1556 break;
1557 case Opt_delalloc:
1558 set_opt(sbi->s_mount_opt, DELALLOC);
1559 break;
1560 case Opt_block_validity:
1561 set_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1562 break;
1563 case Opt_noblock_validity:
1564 clear_opt(sbi->s_mount_opt, BLOCK_VALIDITY);
1565 break;
1566 case Opt_inode_readahead_blks:
1567 if (match_int(&args[0], &option))
1568 return 0;
1569 if (option < 0 || option > (1 << 30))
1570 return 0;
1571 if (!is_power_of_2(option)) {
1572 ext4_msg(sb, KERN_ERR,
1573 "EXT4-fs: inode_readahead_blks"
1574 " must be a power of 2");
1575 return 0;
1576 }
1577 sbi->s_inode_readahead_blks = option;
1578 break;
1579 case Opt_journal_ioprio:
1580 if (match_int(&args[0], &option))
1581 return 0;
1582 if (option < 0 || option > 7)
1583 break;
1584 *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1585 option);
1586 break;
1587 case Opt_noauto_da_alloc:
1588 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1589 break;
1590 case Opt_auto_da_alloc:
1591 if (match_int(&args[0], &option)) {
1592 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1593 break;
1594 }
1595 if (option)
1596 clear_opt(sbi->s_mount_opt, NO_AUTO_DA_ALLOC);
1597 else
1598 set_opt(sbi->s_mount_opt,NO_AUTO_DA_ALLOC);
1599 break;
1600 case Opt_discard:
1601 set_opt(sbi->s_mount_opt, DISCARD);
1602 break;
1603 case Opt_nodiscard:
1604 clear_opt(sbi->s_mount_opt, DISCARD);
1605 break;
1606 default:
1607 ext4_msg(sb, KERN_ERR,
1608 "Unrecognized mount option \"%s\" "
1609 "or missing value", p);
1610 return 0;
1611 }
1612 }
1613 #ifdef CONFIG_QUOTA
1614 if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1615 if ((sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA) &&
1616 sbi->s_qf_names[USRQUOTA])
1617 clear_opt(sbi->s_mount_opt, USRQUOTA);
1618
1619 if ((sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA) &&
1620 sbi->s_qf_names[GRPQUOTA])
1621 clear_opt(sbi->s_mount_opt, GRPQUOTA);
1622
1623 if ((sbi->s_qf_names[USRQUOTA] &&
1624 (sbi->s_mount_opt & EXT4_MOUNT_GRPQUOTA)) ||
1625 (sbi->s_qf_names[GRPQUOTA] &&
1626 (sbi->s_mount_opt & EXT4_MOUNT_USRQUOTA))) {
1627 ext4_msg(sb, KERN_ERR, "old and new quota "
1628 "format mixing");
1629 return 0;
1630 }
1631
1632 if (!sbi->s_jquota_fmt) {
1633 ext4_msg(sb, KERN_ERR, "journaled quota format "
1634 "not specified");
1635 return 0;
1636 }
1637 } else {
1638 if (sbi->s_jquota_fmt) {
1639 ext4_msg(sb, KERN_ERR, "journaled quota format "
1640 "specified with no journaling "
1641 "enabled");
1642 return 0;
1643 }
1644 }
1645 #endif
1646 return 1;
1647 }
1648
1649 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1650 int read_only)
1651 {
1652 struct ext4_sb_info *sbi = EXT4_SB(sb);
1653 int res = 0;
1654
1655 if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1656 ext4_msg(sb, KERN_ERR, "revision level too high, "
1657 "forcing read-only mode");
1658 res = MS_RDONLY;
1659 }
1660 if (read_only)
1661 return res;
1662 if (!(sbi->s_mount_state & EXT4_VALID_FS))
1663 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1664 "running e2fsck is recommended");
1665 else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1666 ext4_msg(sb, KERN_WARNING,
1667 "warning: mounting fs with errors, "
1668 "running e2fsck is recommended");
1669 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1670 le16_to_cpu(es->s_mnt_count) >=
1671 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1672 ext4_msg(sb, KERN_WARNING,
1673 "warning: maximal mount count reached, "
1674 "running e2fsck is recommended");
1675 else if (le32_to_cpu(es->s_checkinterval) &&
1676 (le32_to_cpu(es->s_lastcheck) +
1677 le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1678 ext4_msg(sb, KERN_WARNING,
1679 "warning: checktime reached, "
1680 "running e2fsck is recommended");
1681 if (!sbi->s_journal)
1682 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1683 if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1684 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1685 le16_add_cpu(&es->s_mnt_count, 1);
1686 es->s_mtime = cpu_to_le32(get_seconds());
1687 ext4_update_dynamic_rev(sb);
1688 if (sbi->s_journal)
1689 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1690
1691 ext4_commit_super(sb, 1);
1692 if (test_opt(sb, DEBUG))
1693 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1694 "bpg=%lu, ipg=%lu, mo=%04x]\n",
1695 sb->s_blocksize,
1696 sbi->s_groups_count,
1697 EXT4_BLOCKS_PER_GROUP(sb),
1698 EXT4_INODES_PER_GROUP(sb),
1699 sbi->s_mount_opt);
1700
1701 return res;
1702 }
1703
1704 static int ext4_fill_flex_info(struct super_block *sb)
1705 {
1706 struct ext4_sb_info *sbi = EXT4_SB(sb);
1707 struct ext4_group_desc *gdp = NULL;
1708 ext4_group_t flex_group_count;
1709 ext4_group_t flex_group;
1710 int groups_per_flex = 0;
1711 size_t size;
1712 int i;
1713
1714 sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1715 groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1716
1717 if (groups_per_flex < 2) {
1718 sbi->s_log_groups_per_flex = 0;
1719 return 1;
1720 }
1721
1722 /* We allocate both existing and potentially added groups */
1723 flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1724 ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1725 EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1726 size = flex_group_count * sizeof(struct flex_groups);
1727 sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1728 if (sbi->s_flex_groups == NULL) {
1729 sbi->s_flex_groups = vmalloc(size);
1730 if (sbi->s_flex_groups)
1731 memset(sbi->s_flex_groups, 0, size);
1732 }
1733 if (sbi->s_flex_groups == NULL) {
1734 ext4_msg(sb, KERN_ERR, "not enough memory for "
1735 "%u flex groups", flex_group_count);
1736 goto failed;
1737 }
1738
1739 for (i = 0; i < sbi->s_groups_count; i++) {
1740 gdp = ext4_get_group_desc(sb, i, NULL);
1741
1742 flex_group = ext4_flex_group(sbi, i);
1743 atomic_add(ext4_free_inodes_count(sb, gdp),
1744 &sbi->s_flex_groups[flex_group].free_inodes);
1745 atomic_add(ext4_free_blks_count(sb, gdp),
1746 &sbi->s_flex_groups[flex_group].free_blocks);
1747 atomic_add(ext4_used_dirs_count(sb, gdp),
1748 &sbi->s_flex_groups[flex_group].used_dirs);
1749 }
1750
1751 return 1;
1752 failed:
1753 return 0;
1754 }
1755
1756 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1757 struct ext4_group_desc *gdp)
1758 {
1759 __u16 crc = 0;
1760
1761 if (sbi->s_es->s_feature_ro_compat &
1762 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1763 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1764 __le32 le_group = cpu_to_le32(block_group);
1765
1766 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1767 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1768 crc = crc16(crc, (__u8 *)gdp, offset);
1769 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1770 /* for checksum of struct ext4_group_desc do the rest...*/
1771 if ((sbi->s_es->s_feature_incompat &
1772 cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1773 offset < le16_to_cpu(sbi->s_es->s_desc_size))
1774 crc = crc16(crc, (__u8 *)gdp + offset,
1775 le16_to_cpu(sbi->s_es->s_desc_size) -
1776 offset);
1777 }
1778
1779 return cpu_to_le16(crc);
1780 }
1781
1782 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1783 struct ext4_group_desc *gdp)
1784 {
1785 if ((sbi->s_es->s_feature_ro_compat &
1786 cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1787 (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1788 return 0;
1789
1790 return 1;
1791 }
1792
1793 /* Called at mount-time, super-block is locked */
1794 static int ext4_check_descriptors(struct super_block *sb)
1795 {
1796 struct ext4_sb_info *sbi = EXT4_SB(sb);
1797 ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1798 ext4_fsblk_t last_block;
1799 ext4_fsblk_t block_bitmap;
1800 ext4_fsblk_t inode_bitmap;
1801 ext4_fsblk_t inode_table;
1802 int flexbg_flag = 0;
1803 ext4_group_t i;
1804
1805 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1806 flexbg_flag = 1;
1807
1808 ext4_debug("Checking group descriptors");
1809
1810 for (i = 0; i < sbi->s_groups_count; i++) {
1811 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1812
1813 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1814 last_block = ext4_blocks_count(sbi->s_es) - 1;
1815 else
1816 last_block = first_block +
1817 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1818
1819 block_bitmap = ext4_block_bitmap(sb, gdp);
1820 if (block_bitmap < first_block || block_bitmap > last_block) {
1821 ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1822 "Block bitmap for group %u not in group "
1823 "(block %llu)!", i, block_bitmap);
1824 return 0;
1825 }
1826 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1827 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1828 ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1829 "Inode bitmap for group %u not in group "
1830 "(block %llu)!", i, inode_bitmap);
1831 return 0;
1832 }
1833 inode_table = ext4_inode_table(sb, gdp);
1834 if (inode_table < first_block ||
1835 inode_table + sbi->s_itb_per_group - 1 > last_block) {
1836 ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1837 "Inode table for group %u not in group "
1838 "(block %llu)!", i, inode_table);
1839 return 0;
1840 }
1841 ext4_lock_group(sb, i);
1842 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
1843 ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1844 "Checksum for group %u failed (%u!=%u)",
1845 i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
1846 gdp)), le16_to_cpu(gdp->bg_checksum));
1847 if (!(sb->s_flags & MS_RDONLY)) {
1848 ext4_unlock_group(sb, i);
1849 return 0;
1850 }
1851 }
1852 ext4_unlock_group(sb, i);
1853 if (!flexbg_flag)
1854 first_block += EXT4_BLOCKS_PER_GROUP(sb);
1855 }
1856
1857 ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
1858 sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
1859 return 1;
1860 }
1861
1862 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
1863 * the superblock) which were deleted from all directories, but held open by
1864 * a process at the time of a crash. We walk the list and try to delete these
1865 * inodes at recovery time (only with a read-write filesystem).
1866 *
1867 * In order to keep the orphan inode chain consistent during traversal (in
1868 * case of crash during recovery), we link each inode into the superblock
1869 * orphan list_head and handle it the same way as an inode deletion during
1870 * normal operation (which journals the operations for us).
1871 *
1872 * We only do an iget() and an iput() on each inode, which is very safe if we
1873 * accidentally point at an in-use or already deleted inode. The worst that
1874 * can happen in this case is that we get a "bit already cleared" message from
1875 * ext4_free_inode(). The only reason we would point at a wrong inode is if
1876 * e2fsck was run on this filesystem, and it must have already done the orphan
1877 * inode cleanup for us, so we can safely abort without any further action.
1878 */
1879 static void ext4_orphan_cleanup(struct super_block *sb,
1880 struct ext4_super_block *es)
1881 {
1882 unsigned int s_flags = sb->s_flags;
1883 int nr_orphans = 0, nr_truncates = 0;
1884 #ifdef CONFIG_QUOTA
1885 int i;
1886 #endif
1887 if (!es->s_last_orphan) {
1888 jbd_debug(4, "no orphan inodes to clean up\n");
1889 return;
1890 }
1891
1892 if (bdev_read_only(sb->s_bdev)) {
1893 ext4_msg(sb, KERN_ERR, "write access "
1894 "unavailable, skipping orphan cleanup");
1895 return;
1896 }
1897
1898 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
1899 if (es->s_last_orphan)
1900 jbd_debug(1, "Errors on filesystem, "
1901 "clearing orphan list.\n");
1902 es->s_last_orphan = 0;
1903 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
1904 return;
1905 }
1906
1907 if (s_flags & MS_RDONLY) {
1908 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
1909 sb->s_flags &= ~MS_RDONLY;
1910 }
1911 #ifdef CONFIG_QUOTA
1912 /* Needed for iput() to work correctly and not trash data */
1913 sb->s_flags |= MS_ACTIVE;
1914 /* Turn on quotas so that they are updated correctly */
1915 for (i = 0; i < MAXQUOTAS; i++) {
1916 if (EXT4_SB(sb)->s_qf_names[i]) {
1917 int ret = ext4_quota_on_mount(sb, i);
1918 if (ret < 0)
1919 ext4_msg(sb, KERN_ERR,
1920 "Cannot turn on journaled "
1921 "quota: error %d", ret);
1922 }
1923 }
1924 #endif
1925
1926 while (es->s_last_orphan) {
1927 struct inode *inode;
1928
1929 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
1930 if (IS_ERR(inode)) {
1931 es->s_last_orphan = 0;
1932 break;
1933 }
1934
1935 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
1936 vfs_dq_init(inode);
1937 if (inode->i_nlink) {
1938 ext4_msg(sb, KERN_DEBUG,
1939 "%s: truncating inode %lu to %lld bytes",
1940 __func__, inode->i_ino, inode->i_size);
1941 jbd_debug(2, "truncating inode %lu to %lld bytes\n",
1942 inode->i_ino, inode->i_size);
1943 ext4_truncate(inode);
1944 nr_truncates++;
1945 } else {
1946 ext4_msg(sb, KERN_DEBUG,
1947 "%s: deleting unreferenced inode %lu",
1948 __func__, inode->i_ino);
1949 jbd_debug(2, "deleting unreferenced inode %lu\n",
1950 inode->i_ino);
1951 nr_orphans++;
1952 }
1953 iput(inode); /* The delete magic happens here! */
1954 }
1955
1956 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
1957
1958 if (nr_orphans)
1959 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
1960 PLURAL(nr_orphans));
1961 if (nr_truncates)
1962 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
1963 PLURAL(nr_truncates));
1964 #ifdef CONFIG_QUOTA
1965 /* Turn quotas off */
1966 for (i = 0; i < MAXQUOTAS; i++) {
1967 if (sb_dqopt(sb)->files[i])
1968 vfs_quota_off(sb, i, 0);
1969 }
1970 #endif
1971 sb->s_flags = s_flags; /* Restore MS_RDONLY status */
1972 }
1973
1974 /*
1975 * Maximal extent format file size.
1976 * Resulting logical blkno at s_maxbytes must fit in our on-disk
1977 * extent format containers, within a sector_t, and within i_blocks
1978 * in the vfs. ext4 inode has 48 bits of i_block in fsblock units,
1979 * so that won't be a limiting factor.
1980 *
1981 * Note, this does *not* consider any metadata overhead for vfs i_blocks.
1982 */
1983 static loff_t ext4_max_size(int blkbits, int has_huge_files)
1984 {
1985 loff_t res;
1986 loff_t upper_limit = MAX_LFS_FILESIZE;
1987
1988 /* small i_blocks in vfs inode? */
1989 if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
1990 /*
1991 * CONFIG_LBDAF is not enabled implies the inode
1992 * i_block represent total blocks in 512 bytes
1993 * 32 == size of vfs inode i_blocks * 8
1994 */
1995 upper_limit = (1LL << 32) - 1;
1996
1997 /* total blocks in file system block size */
1998 upper_limit >>= (blkbits - 9);
1999 upper_limit <<= blkbits;
2000 }
2001
2002 /* 32-bit extent-start container, ee_block */
2003 res = 1LL << 32;
2004 res <<= blkbits;
2005 res -= 1;
2006
2007 /* Sanity check against vm- & vfs- imposed limits */
2008 if (res > upper_limit)
2009 res = upper_limit;
2010
2011 return res;
2012 }
2013
2014 /*
2015 * Maximal bitmap file size. There is a direct, and {,double-,triple-}indirect
2016 * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2017 * We need to be 1 filesystem block less than the 2^48 sector limit.
2018 */
2019 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2020 {
2021 loff_t res = EXT4_NDIR_BLOCKS;
2022 int meta_blocks;
2023 loff_t upper_limit;
2024 /* This is calculated to be the largest file size for a dense, block
2025 * mapped file such that the file's total number of 512-byte sectors,
2026 * including data and all indirect blocks, does not exceed (2^48 - 1).
2027 *
2028 * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2029 * number of 512-byte sectors of the file.
2030 */
2031
2032 if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2033 /*
2034 * !has_huge_files or CONFIG_LBDAF not enabled implies that
2035 * the inode i_block field represents total file blocks in
2036 * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2037 */
2038 upper_limit = (1LL << 32) - 1;
2039
2040 /* total blocks in file system block size */
2041 upper_limit >>= (bits - 9);
2042
2043 } else {
2044 /*
2045 * We use 48 bit ext4_inode i_blocks
2046 * With EXT4_HUGE_FILE_FL set the i_blocks
2047 * represent total number of blocks in
2048 * file system block size
2049 */
2050 upper_limit = (1LL << 48) - 1;
2051
2052 }
2053
2054 /* indirect blocks */
2055 meta_blocks = 1;
2056 /* double indirect blocks */
2057 meta_blocks += 1 + (1LL << (bits-2));
2058 /* tripple indirect blocks */
2059 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2060
2061 upper_limit -= meta_blocks;
2062 upper_limit <<= bits;
2063
2064 res += 1LL << (bits-2);
2065 res += 1LL << (2*(bits-2));
2066 res += 1LL << (3*(bits-2));
2067 res <<= bits;
2068 if (res > upper_limit)
2069 res = upper_limit;
2070
2071 if (res > MAX_LFS_FILESIZE)
2072 res = MAX_LFS_FILESIZE;
2073
2074 return res;
2075 }
2076
2077 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2078 ext4_fsblk_t logical_sb_block, int nr)
2079 {
2080 struct ext4_sb_info *sbi = EXT4_SB(sb);
2081 ext4_group_t bg, first_meta_bg;
2082 int has_super = 0;
2083
2084 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2085
2086 if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2087 nr < first_meta_bg)
2088 return logical_sb_block + nr + 1;
2089 bg = sbi->s_desc_per_block * nr;
2090 if (ext4_bg_has_super(sb, bg))
2091 has_super = 1;
2092
2093 return (has_super + ext4_group_first_block_no(sb, bg));
2094 }
2095
2096 /**
2097 * ext4_get_stripe_size: Get the stripe size.
2098 * @sbi: In memory super block info
2099 *
2100 * If we have specified it via mount option, then
2101 * use the mount option value. If the value specified at mount time is
2102 * greater than the blocks per group use the super block value.
2103 * If the super block value is greater than blocks per group return 0.
2104 * Allocator needs it be less than blocks per group.
2105 *
2106 */
2107 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2108 {
2109 unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2110 unsigned long stripe_width =
2111 le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2112
2113 if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2114 return sbi->s_stripe;
2115
2116 if (stripe_width <= sbi->s_blocks_per_group)
2117 return stripe_width;
2118
2119 if (stride <= sbi->s_blocks_per_group)
2120 return stride;
2121
2122 return 0;
2123 }
2124
2125 /* sysfs supprt */
2126
2127 struct ext4_attr {
2128 struct attribute attr;
2129 ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2130 ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2131 const char *, size_t);
2132 int offset;
2133 };
2134
2135 static int parse_strtoul(const char *buf,
2136 unsigned long max, unsigned long *value)
2137 {
2138 char *endp;
2139
2140 *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2141 endp = skip_spaces(endp);
2142 if (*endp || *value > max)
2143 return -EINVAL;
2144
2145 return 0;
2146 }
2147
2148 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2149 struct ext4_sb_info *sbi,
2150 char *buf)
2151 {
2152 return snprintf(buf, PAGE_SIZE, "%llu\n",
2153 (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2154 }
2155
2156 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2157 struct ext4_sb_info *sbi, char *buf)
2158 {
2159 struct super_block *sb = sbi->s_buddy_cache->i_sb;
2160
2161 return snprintf(buf, PAGE_SIZE, "%lu\n",
2162 (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2163 sbi->s_sectors_written_start) >> 1);
2164 }
2165
2166 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2167 struct ext4_sb_info *sbi, char *buf)
2168 {
2169 struct super_block *sb = sbi->s_buddy_cache->i_sb;
2170
2171 return snprintf(buf, PAGE_SIZE, "%llu\n",
2172 sbi->s_kbytes_written +
2173 ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2174 EXT4_SB(sb)->s_sectors_written_start) >> 1));
2175 }
2176
2177 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2178 struct ext4_sb_info *sbi,
2179 const char *buf, size_t count)
2180 {
2181 unsigned long t;
2182
2183 if (parse_strtoul(buf, 0x40000000, &t))
2184 return -EINVAL;
2185
2186 if (!is_power_of_2(t))
2187 return -EINVAL;
2188
2189 sbi->s_inode_readahead_blks = t;
2190 return count;
2191 }
2192
2193 static ssize_t sbi_ui_show(struct ext4_attr *a,
2194 struct ext4_sb_info *sbi, char *buf)
2195 {
2196 unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2197
2198 return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2199 }
2200
2201 static ssize_t sbi_ui_store(struct ext4_attr *a,
2202 struct ext4_sb_info *sbi,
2203 const char *buf, size_t count)
2204 {
2205 unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2206 unsigned long t;
2207
2208 if (parse_strtoul(buf, 0xffffffff, &t))
2209 return -EINVAL;
2210 *ui = t;
2211 return count;
2212 }
2213
2214 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2215 static struct ext4_attr ext4_attr_##_name = { \
2216 .attr = {.name = __stringify(_name), .mode = _mode }, \
2217 .show = _show, \
2218 .store = _store, \
2219 .offset = offsetof(struct ext4_sb_info, _elname), \
2220 }
2221 #define EXT4_ATTR(name, mode, show, store) \
2222 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2223
2224 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2225 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2226 #define EXT4_RW_ATTR_SBI_UI(name, elname) \
2227 EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2228 #define ATTR_LIST(name) &ext4_attr_##name.attr
2229
2230 EXT4_RO_ATTR(delayed_allocation_blocks);
2231 EXT4_RO_ATTR(session_write_kbytes);
2232 EXT4_RO_ATTR(lifetime_write_kbytes);
2233 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2234 inode_readahead_blks_store, s_inode_readahead_blks);
2235 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2236 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2237 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2238 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2239 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2240 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2241 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2242 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2243
2244 static struct attribute *ext4_attrs[] = {
2245 ATTR_LIST(delayed_allocation_blocks),
2246 ATTR_LIST(session_write_kbytes),
2247 ATTR_LIST(lifetime_write_kbytes),
2248 ATTR_LIST(inode_readahead_blks),
2249 ATTR_LIST(inode_goal),
2250 ATTR_LIST(mb_stats),
2251 ATTR_LIST(mb_max_to_scan),
2252 ATTR_LIST(mb_min_to_scan),
2253 ATTR_LIST(mb_order2_req),
2254 ATTR_LIST(mb_stream_req),
2255 ATTR_LIST(mb_group_prealloc),
2256 ATTR_LIST(max_writeback_mb_bump),
2257 NULL,
2258 };
2259
2260 static ssize_t ext4_attr_show(struct kobject *kobj,
2261 struct attribute *attr, char *buf)
2262 {
2263 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2264 s_kobj);
2265 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2266
2267 return a->show ? a->show(a, sbi, buf) : 0;
2268 }
2269
2270 static ssize_t ext4_attr_store(struct kobject *kobj,
2271 struct attribute *attr,
2272 const char *buf, size_t len)
2273 {
2274 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2275 s_kobj);
2276 struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2277
2278 return a->store ? a->store(a, sbi, buf, len) : 0;
2279 }
2280
2281 static void ext4_sb_release(struct kobject *kobj)
2282 {
2283 struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2284 s_kobj);
2285 complete(&sbi->s_kobj_unregister);
2286 }
2287
2288
2289 static struct sysfs_ops ext4_attr_ops = {
2290 .show = ext4_attr_show,
2291 .store = ext4_attr_store,
2292 };
2293
2294 static struct kobj_type ext4_ktype = {
2295 .default_attrs = ext4_attrs,
2296 .sysfs_ops = &ext4_attr_ops,
2297 .release = ext4_sb_release,
2298 };
2299
2300 /*
2301 * Check whether this filesystem can be mounted based on
2302 * the features present and the RDONLY/RDWR mount requested.
2303 * Returns 1 if this filesystem can be mounted as requested,
2304 * 0 if it cannot be.
2305 */
2306 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2307 {
2308 if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2309 ext4_msg(sb, KERN_ERR,
2310 "Couldn't mount because of "
2311 "unsupported optional features (%x)",
2312 (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2313 ~EXT4_FEATURE_INCOMPAT_SUPP));
2314 return 0;
2315 }
2316
2317 if (readonly)
2318 return 1;
2319
2320 /* Check that feature set is OK for a read-write mount */
2321 if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2322 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2323 "unsupported optional features (%x)",
2324 (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2325 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2326 return 0;
2327 }
2328 /*
2329 * Large file size enabled file system can only be mounted
2330 * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2331 */
2332 if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2333 if (sizeof(blkcnt_t) < sizeof(u64)) {
2334 ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2335 "cannot be mounted RDWR without "
2336 "CONFIG_LBDAF");
2337 return 0;
2338 }
2339 }
2340 return 1;
2341 }
2342
2343 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2344 __releases(kernel_lock)
2345 __acquires(kernel_lock)
2346 {
2347 struct buffer_head *bh;
2348 struct ext4_super_block *es = NULL;
2349 struct ext4_sb_info *sbi;
2350 ext4_fsblk_t block;
2351 ext4_fsblk_t sb_block = get_sb_block(&data);
2352 ext4_fsblk_t logical_sb_block;
2353 unsigned long offset = 0;
2354 unsigned long journal_devnum = 0;
2355 unsigned long def_mount_opts;
2356 struct inode *root;
2357 char *cp;
2358 const char *descr;
2359 int ret = -EINVAL;
2360 int blocksize;
2361 unsigned int db_count;
2362 unsigned int i;
2363 int needs_recovery, has_huge_files;
2364 __u64 blocks_count;
2365 int err;
2366 unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2367
2368 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2369 if (!sbi)
2370 return -ENOMEM;
2371
2372 sbi->s_blockgroup_lock =
2373 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2374 if (!sbi->s_blockgroup_lock) {
2375 kfree(sbi);
2376 return -ENOMEM;
2377 }
2378 sb->s_fs_info = sbi;
2379 sbi->s_mount_opt = 0;
2380 sbi->s_resuid = EXT4_DEF_RESUID;
2381 sbi->s_resgid = EXT4_DEF_RESGID;
2382 sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2383 sbi->s_sb_block = sb_block;
2384 sbi->s_sectors_written_start = part_stat_read(sb->s_bdev->bd_part,
2385 sectors[1]);
2386
2387 unlock_kernel();
2388
2389 /* Cleanup superblock name */
2390 for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2391 *cp = '!';
2392
2393 blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2394 if (!blocksize) {
2395 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2396 goto out_fail;
2397 }
2398
2399 /*
2400 * The ext4 superblock will not be buffer aligned for other than 1kB
2401 * block sizes. We need to calculate the offset from buffer start.
2402 */
2403 if (blocksize != EXT4_MIN_BLOCK_SIZE) {
2404 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2405 offset = do_div(logical_sb_block, blocksize);
2406 } else {
2407 logical_sb_block = sb_block;
2408 }
2409
2410 if (!(bh = sb_bread(sb, logical_sb_block))) {
2411 ext4_msg(sb, KERN_ERR, "unable to read superblock");
2412 goto out_fail;
2413 }
2414 /*
2415 * Note: s_es must be initialized as soon as possible because
2416 * some ext4 macro-instructions depend on its value
2417 */
2418 es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
2419 sbi->s_es = es;
2420 sb->s_magic = le16_to_cpu(es->s_magic);
2421 if (sb->s_magic != EXT4_SUPER_MAGIC)
2422 goto cantfind_ext4;
2423 sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
2424
2425 /* Set defaults before we parse the mount options */
2426 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
2427 if (def_mount_opts & EXT4_DEFM_DEBUG)
2428 set_opt(sbi->s_mount_opt, DEBUG);
2429 if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
2430 set_opt(sbi->s_mount_opt, GRPID);
2431 if (def_mount_opts & EXT4_DEFM_UID16)
2432 set_opt(sbi->s_mount_opt, NO_UID32);
2433 #ifdef CONFIG_EXT4_FS_XATTR
2434 if (def_mount_opts & EXT4_DEFM_XATTR_USER)
2435 set_opt(sbi->s_mount_opt, XATTR_USER);
2436 #endif
2437 #ifdef CONFIG_EXT4_FS_POSIX_ACL
2438 if (def_mount_opts & EXT4_DEFM_ACL)
2439 set_opt(sbi->s_mount_opt, POSIX_ACL);
2440 #endif
2441 if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
2442 sbi->s_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
2443 else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
2444 sbi->s_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
2445 else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
2446 sbi->s_mount_opt |= EXT4_MOUNT_WRITEBACK_DATA;
2447
2448 if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
2449 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
2450 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
2451 set_opt(sbi->s_mount_opt, ERRORS_CONT);
2452 else
2453 set_opt(sbi->s_mount_opt, ERRORS_RO);
2454
2455 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
2456 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
2457 sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
2458 sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
2459 sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
2460
2461 set_opt(sbi->s_mount_opt, BARRIER);
2462
2463 /*
2464 * enable delayed allocation by default
2465 * Use -o nodelalloc to turn it off
2466 */
2467 set_opt(sbi->s_mount_opt, DELALLOC);
2468
2469 if (!parse_options((char *) data, sb, &journal_devnum,
2470 &journal_ioprio, NULL, 0))
2471 goto failed_mount;
2472
2473 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
2474 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
2475
2476 if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
2477 (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
2478 EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
2479 EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
2480 ext4_msg(sb, KERN_WARNING,
2481 "feature flags set on rev 0 fs, "
2482 "running e2fsck is recommended");
2483
2484 /*
2485 * Check feature flags regardless of the revision level, since we
2486 * previously didn't change the revision level when setting the flags,
2487 * so there is a chance incompat flags are set on a rev 0 filesystem.
2488 */
2489 if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
2490 goto failed_mount;
2491
2492 blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
2493
2494 if (blocksize < EXT4_MIN_BLOCK_SIZE ||
2495 blocksize > EXT4_MAX_BLOCK_SIZE) {
2496 ext4_msg(sb, KERN_ERR,
2497 "Unsupported filesystem blocksize %d", blocksize);
2498 goto failed_mount;
2499 }
2500
2501 if (sb->s_blocksize != blocksize) {
2502 /* Validate the filesystem blocksize */
2503 if (!sb_set_blocksize(sb, blocksize)) {
2504 ext4_msg(sb, KERN_ERR, "bad block size %d",
2505 blocksize);
2506 goto failed_mount;
2507 }
2508
2509 brelse(bh);
2510 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
2511 offset = do_div(logical_sb_block, blocksize);
2512 bh = sb_bread(sb, logical_sb_block);
2513 if (!bh) {
2514 ext4_msg(sb, KERN_ERR,
2515 "Can't read superblock on 2nd try");
2516 goto failed_mount;
2517 }
2518 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
2519 sbi->s_es = es;
2520 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
2521 ext4_msg(sb, KERN_ERR,
2522 "Magic mismatch, very weird!");
2523 goto failed_mount;
2524 }
2525 }
2526
2527 has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
2528 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
2529 sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
2530 has_huge_files);
2531 sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
2532
2533 if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
2534 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
2535 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
2536 } else {
2537 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
2538 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
2539 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
2540 (!is_power_of_2(sbi->s_inode_size)) ||
2541 (sbi->s_inode_size > blocksize)) {
2542 ext4_msg(sb, KERN_ERR,
2543 "unsupported inode size: %d",
2544 sbi->s_inode_size);
2545 goto failed_mount;
2546 }
2547 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
2548 sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
2549 }
2550
2551 sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
2552 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
2553 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
2554 sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
2555 !is_power_of_2(sbi->s_desc_size)) {
2556 ext4_msg(sb, KERN_ERR,
2557 "unsupported descriptor size %lu",
2558 sbi->s_desc_size);
2559 goto failed_mount;
2560 }
2561 } else
2562 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
2563
2564 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
2565 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
2566 if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
2567 goto cantfind_ext4;
2568
2569 sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
2570 if (sbi->s_inodes_per_block == 0)
2571 goto cantfind_ext4;
2572 sbi->s_itb_per_group = sbi->s_inodes_per_group /
2573 sbi->s_inodes_per_block;
2574 sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
2575 sbi->s_sbh = bh;
2576 sbi->s_mount_state = le16_to_cpu(es->s_state);
2577 sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
2578 sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
2579
2580 for (i = 0; i < 4; i++)
2581 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
2582 sbi->s_def_hash_version = es->s_def_hash_version;
2583 i = le32_to_cpu(es->s_flags);
2584 if (i & EXT2_FLAGS_UNSIGNED_HASH)
2585 sbi->s_hash_unsigned = 3;
2586 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
2587 #ifdef __CHAR_UNSIGNED__
2588 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
2589 sbi->s_hash_unsigned = 3;
2590 #else
2591 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
2592 #endif
2593 sb->s_dirt = 1;
2594 }
2595
2596 if (sbi->s_blocks_per_group > blocksize * 8) {
2597 ext4_msg(sb, KERN_ERR,
2598 "#blocks per group too big: %lu",
2599 sbi->s_blocks_per_group);
2600 goto failed_mount;
2601 }
2602 if (sbi->s_inodes_per_group > blocksize * 8) {
2603 ext4_msg(sb, KERN_ERR,
2604 "#inodes per group too big: %lu",
2605 sbi->s_inodes_per_group);
2606 goto failed_mount;
2607 }
2608
2609 /*
2610 * Test whether we have more sectors than will fit in sector_t,
2611 * and whether the max offset is addressable by the page cache.
2612 */
2613 if ((ext4_blocks_count(es) >
2614 (sector_t)(~0ULL) >> (sb->s_blocksize_bits - 9)) ||
2615 (ext4_blocks_count(es) >
2616 (pgoff_t)(~0ULL) >> (PAGE_CACHE_SHIFT - sb->s_blocksize_bits))) {
2617 ext4_msg(sb, KERN_ERR, "filesystem"
2618 " too large to mount safely on this system");
2619 if (sizeof(sector_t) < 8)
2620 ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
2621 ret = -EFBIG;
2622 goto failed_mount;
2623 }
2624
2625 if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
2626 goto cantfind_ext4;
2627
2628 /* check blocks count against device size */
2629 blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
2630 if (blocks_count && ext4_blocks_count(es) > blocks_count) {
2631 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
2632 "exceeds size of device (%llu blocks)",
2633 ext4_blocks_count(es), blocks_count);
2634 goto failed_mount;
2635 }
2636
2637 /*
2638 * It makes no sense for the first data block to be beyond the end
2639 * of the filesystem.
2640 */
2641 if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
2642 ext4_msg(sb, KERN_WARNING, "bad geometry: first data"
2643 "block %u is beyond end of filesystem (%llu)",
2644 le32_to_cpu(es->s_first_data_block),
2645 ext4_blocks_count(es));
2646 goto failed_mount;
2647 }
2648 blocks_count = (ext4_blocks_count(es) -
2649 le32_to_cpu(es->s_first_data_block) +
2650 EXT4_BLOCKS_PER_GROUP(sb) - 1);
2651 do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
2652 if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
2653 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
2654 "(block count %llu, first data block %u, "
2655 "blocks per group %lu)", sbi->s_groups_count,
2656 ext4_blocks_count(es),
2657 le32_to_cpu(es->s_first_data_block),
2658 EXT4_BLOCKS_PER_GROUP(sb));
2659 goto failed_mount;
2660 }
2661 sbi->s_groups_count = blocks_count;
2662 sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
2663 (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
2664 db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
2665 EXT4_DESC_PER_BLOCK(sb);
2666 sbi->s_group_desc = kmalloc(db_count * sizeof(struct buffer_head *),
2667 GFP_KERNEL);
2668 if (sbi->s_group_desc == NULL) {
2669 ext4_msg(sb, KERN_ERR, "not enough memory");
2670 goto failed_mount;
2671 }
2672
2673 #ifdef CONFIG_PROC_FS
2674 if (ext4_proc_root)
2675 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
2676 #endif
2677
2678 bgl_lock_init(sbi->s_blockgroup_lock);
2679
2680 for (i = 0; i < db_count; i++) {
2681 block = descriptor_loc(sb, logical_sb_block, i);
2682 sbi->s_group_desc[i] = sb_bread(sb, block);
2683 if (!sbi->s_group_desc[i]) {
2684 ext4_msg(sb, KERN_ERR,
2685 "can't read group descriptor %d", i);
2686 db_count = i;
2687 goto failed_mount2;
2688 }
2689 }
2690 if (!ext4_check_descriptors(sb)) {
2691 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
2692 goto failed_mount2;
2693 }
2694 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2695 if (!ext4_fill_flex_info(sb)) {
2696 ext4_msg(sb, KERN_ERR,
2697 "unable to initialize "
2698 "flex_bg meta info!");
2699 goto failed_mount2;
2700 }
2701
2702 sbi->s_gdb_count = db_count;
2703 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
2704 spin_lock_init(&sbi->s_next_gen_lock);
2705
2706 err = percpu_counter_init(&sbi->s_freeblocks_counter,
2707 ext4_count_free_blocks(sb));
2708 if (!err) {
2709 err = percpu_counter_init(&sbi->s_freeinodes_counter,
2710 ext4_count_free_inodes(sb));
2711 }
2712 if (!err) {
2713 err = percpu_counter_init(&sbi->s_dirs_counter,
2714 ext4_count_dirs(sb));
2715 }
2716 if (!err) {
2717 err = percpu_counter_init(&sbi->s_dirtyblocks_counter, 0);
2718 }
2719 if (err) {
2720 ext4_msg(sb, KERN_ERR, "insufficient memory");
2721 goto failed_mount3;
2722 }
2723
2724 sbi->s_stripe = ext4_get_stripe_size(sbi);
2725 sbi->s_max_writeback_mb_bump = 128;
2726
2727 /*
2728 * set up enough so that it can read an inode
2729 */
2730 if (!test_opt(sb, NOLOAD) &&
2731 EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
2732 sb->s_op = &ext4_sops;
2733 else
2734 sb->s_op = &ext4_nojournal_sops;
2735 sb->s_export_op = &ext4_export_ops;
2736 sb->s_xattr = ext4_xattr_handlers;
2737 #ifdef CONFIG_QUOTA
2738 sb->s_qcop = &ext4_qctl_operations;
2739 sb->dq_op = &ext4_quota_operations;
2740 #endif
2741 INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
2742 mutex_init(&sbi->s_orphan_lock);
2743 mutex_init(&sbi->s_resize_lock);
2744
2745 sb->s_root = NULL;
2746
2747 needs_recovery = (es->s_last_orphan != 0 ||
2748 EXT4_HAS_INCOMPAT_FEATURE(sb,
2749 EXT4_FEATURE_INCOMPAT_RECOVER));
2750
2751 /*
2752 * The first inode we look at is the journal inode. Don't try
2753 * root first: it may be modified in the journal!
2754 */
2755 if (!test_opt(sb, NOLOAD) &&
2756 EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
2757 if (ext4_load_journal(sb, es, journal_devnum))
2758 goto failed_mount3;
2759 } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
2760 EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
2761 ext4_msg(sb, KERN_ERR, "required journal recovery "
2762 "suppressed and not mounted read-only");
2763 goto failed_mount4;
2764 } else {
2765 clear_opt(sbi->s_mount_opt, DATA_FLAGS);
2766 set_opt(sbi->s_mount_opt, WRITEBACK_DATA);
2767 sbi->s_journal = NULL;
2768 needs_recovery = 0;
2769 goto no_journal;
2770 }
2771
2772 if (ext4_blocks_count(es) > 0xffffffffULL &&
2773 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
2774 JBD2_FEATURE_INCOMPAT_64BIT)) {
2775 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
2776 goto failed_mount4;
2777 }
2778
2779 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
2780 jbd2_journal_set_features(sbi->s_journal,
2781 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2782 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2783 } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
2784 jbd2_journal_set_features(sbi->s_journal,
2785 JBD2_FEATURE_COMPAT_CHECKSUM, 0, 0);
2786 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
2787 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2788 } else {
2789 jbd2_journal_clear_features(sbi->s_journal,
2790 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
2791 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
2792 }
2793
2794 /* We have now updated the journal if required, so we can
2795 * validate the data journaling mode. */
2796 switch (test_opt(sb, DATA_FLAGS)) {
2797 case 0:
2798 /* No mode set, assume a default based on the journal
2799 * capabilities: ORDERED_DATA if the journal can
2800 * cope, else JOURNAL_DATA
2801 */
2802 if (jbd2_journal_check_available_features
2803 (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
2804 set_opt(sbi->s_mount_opt, ORDERED_DATA);
2805 else
2806 set_opt(sbi->s_mount_opt, JOURNAL_DATA);
2807 break;
2808
2809 case EXT4_MOUNT_ORDERED_DATA:
2810 case EXT4_MOUNT_WRITEBACK_DATA:
2811 if (!jbd2_journal_check_available_features
2812 (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
2813 ext4_msg(sb, KERN_ERR, "Journal does not support "
2814 "requested data journaling mode");
2815 goto failed_mount4;
2816 }
2817 default:
2818 break;
2819 }
2820 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
2821
2822 no_journal:
2823
2824 if (test_opt(sb, NOBH)) {
2825 if (!(test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)) {
2826 ext4_msg(sb, KERN_WARNING, "Ignoring nobh option - "
2827 "its supported only with writeback mode");
2828 clear_opt(sbi->s_mount_opt, NOBH);
2829 }
2830 }
2831 EXT4_SB(sb)->dio_unwritten_wq = create_workqueue("ext4-dio-unwritten");
2832 if (!EXT4_SB(sb)->dio_unwritten_wq) {
2833 printk(KERN_ERR "EXT4-fs: failed to create DIO workqueue\n");
2834 goto failed_mount_wq;
2835 }
2836
2837 /*
2838 * The jbd2_journal_load will have done any necessary log recovery,
2839 * so we can safely mount the rest of the filesystem now.
2840 */
2841
2842 root = ext4_iget(sb, EXT4_ROOT_INO);
2843 if (IS_ERR(root)) {
2844 ext4_msg(sb, KERN_ERR, "get root inode failed");
2845 ret = PTR_ERR(root);
2846 goto failed_mount4;
2847 }
2848 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
2849 iput(root);
2850 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
2851 goto failed_mount4;
2852 }
2853 sb->s_root = d_alloc_root(root);
2854 if (!sb->s_root) {
2855 ext4_msg(sb, KERN_ERR, "get root dentry failed");
2856 iput(root);
2857 ret = -ENOMEM;
2858 goto failed_mount4;
2859 }
2860
2861 ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY);
2862
2863 /* determine the minimum size of new large inodes, if present */
2864 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
2865 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2866 EXT4_GOOD_OLD_INODE_SIZE;
2867 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
2868 EXT4_FEATURE_RO_COMPAT_EXTRA_ISIZE)) {
2869 if (sbi->s_want_extra_isize <
2870 le16_to_cpu(es->s_want_extra_isize))
2871 sbi->s_want_extra_isize =
2872 le16_to_cpu(es->s_want_extra_isize);
2873 if (sbi->s_want_extra_isize <
2874 le16_to_cpu(es->s_min_extra_isize))
2875 sbi->s_want_extra_isize =
2876 le16_to_cpu(es->s_min_extra_isize);
2877 }
2878 }
2879 /* Check if enough inode space is available */
2880 if (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
2881 sbi->s_inode_size) {
2882 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
2883 EXT4_GOOD_OLD_INODE_SIZE;
2884 ext4_msg(sb, KERN_INFO, "required extra inode space not"
2885 "available");
2886 }
2887
2888 if (test_opt(sb, DELALLOC) &&
2889 (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)) {
2890 ext4_msg(sb, KERN_WARNING, "Ignoring delalloc option - "
2891 "requested data journaling mode");
2892 clear_opt(sbi->s_mount_opt, DELALLOC);
2893 }
2894
2895 err = ext4_setup_system_zone(sb);
2896 if (err) {
2897 ext4_msg(sb, KERN_ERR, "failed to initialize system "
2898 "zone (%d)\n", err);
2899 goto failed_mount4;
2900 }
2901
2902 ext4_ext_init(sb);
2903 err = ext4_mb_init(sb, needs_recovery);
2904 if (err) {
2905 ext4_msg(sb, KERN_ERR, "failed to initalize mballoc (%d)",
2906 err);
2907 goto failed_mount4;
2908 }
2909
2910 sbi->s_kobj.kset = ext4_kset;
2911 init_completion(&sbi->s_kobj_unregister);
2912 err = kobject_init_and_add(&sbi->s_kobj, &ext4_ktype, NULL,
2913 "%s", sb->s_id);
2914 if (err) {
2915 ext4_mb_release(sb);
2916 ext4_ext_release(sb);
2917 goto failed_mount4;
2918 };
2919
2920 EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
2921 ext4_orphan_cleanup(sb, es);
2922 EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
2923 if (needs_recovery) {
2924 ext4_msg(sb, KERN_INFO, "recovery complete");
2925 ext4_mark_recovery_complete(sb, es);
2926 }
2927 if (EXT4_SB(sb)->s_journal) {
2928 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2929 descr = " journalled data mode";
2930 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2931 descr = " ordered data mode";
2932 else
2933 descr = " writeback data mode";
2934 } else
2935 descr = "out journal";
2936
2937 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s", descr);
2938
2939 lock_kernel();
2940 return 0;
2941
2942 cantfind_ext4:
2943 if (!silent)
2944 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
2945 goto failed_mount;
2946
2947 failed_mount4:
2948 ext4_msg(sb, KERN_ERR, "mount failed");
2949 destroy_workqueue(EXT4_SB(sb)->dio_unwritten_wq);
2950 failed_mount_wq:
2951 ext4_release_system_zone(sb);
2952 if (sbi->s_journal) {
2953 jbd2_journal_destroy(sbi->s_journal);
2954 sbi->s_journal = NULL;
2955 }
2956 failed_mount3:
2957 if (sbi->s_flex_groups) {
2958 if (is_vmalloc_addr(sbi->s_flex_groups))
2959 vfree(sbi->s_flex_groups);
2960 else
2961 kfree(sbi->s_flex_groups);
2962 }
2963 percpu_counter_destroy(&sbi->s_freeblocks_counter);
2964 percpu_counter_destroy(&sbi->s_freeinodes_counter);
2965 percpu_counter_destroy(&sbi->s_dirs_counter);
2966 percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
2967 failed_mount2:
2968 for (i = 0; i < db_count; i++)
2969 brelse(sbi->s_group_desc[i]);
2970 kfree(sbi->s_group_desc);
2971 failed_mount:
2972 if (sbi->s_proc) {
2973 remove_proc_entry(sb->s_id, ext4_proc_root);
2974 }
2975 #ifdef CONFIG_QUOTA
2976 for (i = 0; i < MAXQUOTAS; i++)
2977 kfree(sbi->s_qf_names[i]);
2978 #endif
2979 ext4_blkdev_remove(sbi);
2980 brelse(bh);
2981 out_fail:
2982 sb->s_fs_info = NULL;
2983 kfree(sbi->s_blockgroup_lock);
2984 kfree(sbi);
2985 lock_kernel();
2986 return ret;
2987 }
2988
2989 /*
2990 * Setup any per-fs journal parameters now. We'll do this both on
2991 * initial mount, once the journal has been initialised but before we've
2992 * done any recovery; and again on any subsequent remount.
2993 */
2994 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
2995 {
2996 struct ext4_sb_info *sbi = EXT4_SB(sb);
2997
2998 journal->j_commit_interval = sbi->s_commit_interval;
2999 journal->j_min_batch_time = sbi->s_min_batch_time;
3000 journal->j_max_batch_time = sbi->s_max_batch_time;
3001
3002 spin_lock(&journal->j_state_lock);
3003 if (test_opt(sb, BARRIER))
3004 journal->j_flags |= JBD2_BARRIER;
3005 else
3006 journal->j_flags &= ~JBD2_BARRIER;
3007 if (test_opt(sb, DATA_ERR_ABORT))
3008 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
3009 else
3010 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
3011 spin_unlock(&journal->j_state_lock);
3012 }
3013
3014 static journal_t *ext4_get_journal(struct super_block *sb,
3015 unsigned int journal_inum)
3016 {
3017 struct inode *journal_inode;
3018 journal_t *journal;
3019
3020 BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3021
3022 /* First, test for the existence of a valid inode on disk. Bad
3023 * things happen if we iget() an unused inode, as the subsequent
3024 * iput() will try to delete it. */
3025
3026 journal_inode = ext4_iget(sb, journal_inum);
3027 if (IS_ERR(journal_inode)) {
3028 ext4_msg(sb, KERN_ERR, "no journal found");
3029 return NULL;
3030 }
3031 if (!journal_inode->i_nlink) {
3032 make_bad_inode(journal_inode);
3033 iput(journal_inode);
3034 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
3035 return NULL;
3036 }
3037
3038 jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
3039 journal_inode, journal_inode->i_size);
3040 if (!S_ISREG(journal_inode->i_mode)) {
3041 ext4_msg(sb, KERN_ERR, "invalid journal inode");
3042 iput(journal_inode);
3043 return NULL;
3044 }
3045
3046 journal = jbd2_journal_init_inode(journal_inode);
3047 if (!journal) {
3048 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
3049 iput(journal_inode);
3050 return NULL;
3051 }
3052 journal->j_private = sb;
3053 ext4_init_journal_params(sb, journal);
3054 return journal;
3055 }
3056
3057 static journal_t *ext4_get_dev_journal(struct super_block *sb,
3058 dev_t j_dev)
3059 {
3060 struct buffer_head *bh;
3061 journal_t *journal;
3062 ext4_fsblk_t start;
3063 ext4_fsblk_t len;
3064 int hblock, blocksize;
3065 ext4_fsblk_t sb_block;
3066 unsigned long offset;
3067 struct ext4_super_block *es;
3068 struct block_device *bdev;
3069
3070 BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3071
3072 bdev = ext4_blkdev_get(j_dev, sb);
3073 if (bdev == NULL)
3074 return NULL;
3075
3076 if (bd_claim(bdev, sb)) {
3077 ext4_msg(sb, KERN_ERR,
3078 "failed to claim external journal device");
3079 blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
3080 return NULL;
3081 }
3082
3083 blocksize = sb->s_blocksize;
3084 hblock = bdev_logical_block_size(bdev);
3085 if (blocksize < hblock) {
3086 ext4_msg(sb, KERN_ERR,
3087 "blocksize too small for journal device");
3088 goto out_bdev;
3089 }
3090
3091 sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
3092 offset = EXT4_MIN_BLOCK_SIZE % blocksize;
3093 set_blocksize(bdev, blocksize);
3094 if (!(bh = __bread(bdev, sb_block, blocksize))) {
3095 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
3096 "external journal");
3097 goto out_bdev;
3098 }
3099
3100 es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3101 if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
3102 !(le32_to_cpu(es->s_feature_incompat) &
3103 EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
3104 ext4_msg(sb, KERN_ERR, "external journal has "
3105 "bad superblock");
3106 brelse(bh);
3107 goto out_bdev;
3108 }
3109
3110 if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
3111 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
3112 brelse(bh);
3113 goto out_bdev;
3114 }
3115
3116 len = ext4_blocks_count(es);
3117 start = sb_block + 1;
3118 brelse(bh); /* we're done with the superblock */
3119
3120 journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
3121 start, len, blocksize);
3122 if (!journal) {
3123 ext4_msg(sb, KERN_ERR, "failed to create device journal");
3124 goto out_bdev;
3125 }
3126 journal->j_private = sb;
3127 ll_rw_block(READ, 1, &journal->j_sb_buffer);
3128 wait_on_buffer(journal->j_sb_buffer);
3129 if (!buffer_uptodate(journal->j_sb_buffer)) {
3130 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
3131 goto out_journal;
3132 }
3133 if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
3134 ext4_msg(sb, KERN_ERR, "External journal has more than one "
3135 "user (unsupported) - %d",
3136 be32_to_cpu(journal->j_superblock->s_nr_users));
3137 goto out_journal;
3138 }
3139 EXT4_SB(sb)->journal_bdev = bdev;
3140 ext4_init_journal_params(sb, journal);
3141 return journal;
3142
3143 out_journal:
3144 jbd2_journal_destroy(journal);
3145 out_bdev:
3146 ext4_blkdev_put(bdev);
3147 return NULL;
3148 }
3149
3150 static int ext4_load_journal(struct super_block *sb,
3151 struct ext4_super_block *es,
3152 unsigned long journal_devnum)
3153 {
3154 journal_t *journal;
3155 unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
3156 dev_t journal_dev;
3157 int err = 0;
3158 int really_read_only;
3159
3160 BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3161
3162 if (journal_devnum &&
3163 journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3164 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
3165 "numbers have changed");
3166 journal_dev = new_decode_dev(journal_devnum);
3167 } else
3168 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
3169
3170 really_read_only = bdev_read_only(sb->s_bdev);
3171
3172 /*
3173 * Are we loading a blank journal or performing recovery after a
3174 * crash? For recovery, we need to check in advance whether we
3175 * can get read-write access to the device.
3176 */
3177 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3178 if (sb->s_flags & MS_RDONLY) {
3179 ext4_msg(sb, KERN_INFO, "INFO: recovery "
3180 "required on readonly filesystem");
3181 if (really_read_only) {
3182 ext4_msg(sb, KERN_ERR, "write access "
3183 "unavailable, cannot proceed");
3184 return -EROFS;
3185 }
3186 ext4_msg(sb, KERN_INFO, "write access will "
3187 "be enabled during recovery");
3188 }
3189 }
3190
3191 if (journal_inum && journal_dev) {
3192 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
3193 "and inode journals!");
3194 return -EINVAL;
3195 }
3196
3197 if (journal_inum) {
3198 if (!(journal = ext4_get_journal(sb, journal_inum)))
3199 return -EINVAL;
3200 } else {
3201 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
3202 return -EINVAL;
3203 }
3204
3205 if (!(journal->j_flags & JBD2_BARRIER))
3206 ext4_msg(sb, KERN_INFO, "barriers disabled");
3207
3208 if (!really_read_only && test_opt(sb, UPDATE_JOURNAL)) {
3209 err = jbd2_journal_update_format(journal);
3210 if (err) {
3211 ext4_msg(sb, KERN_ERR, "error updating journal");
3212 jbd2_journal_destroy(journal);
3213 return err;
3214 }
3215 }
3216
3217 if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER))
3218 err = jbd2_journal_wipe(journal, !really_read_only);
3219 if (!err)
3220 err = jbd2_journal_load(journal);
3221
3222 if (err) {
3223 ext4_msg(sb, KERN_ERR, "error loading journal");
3224 jbd2_journal_destroy(journal);
3225 return err;
3226 }
3227
3228 EXT4_SB(sb)->s_journal = journal;
3229 ext4_clear_journal_err(sb, es);
3230
3231 if (journal_devnum &&
3232 journal_devnum != le32_to_cpu(es->s_journal_dev)) {
3233 es->s_journal_dev = cpu_to_le32(journal_devnum);
3234
3235 /* Make sure we flush the recovery flag to disk. */
3236 ext4_commit_super(sb, 1);
3237 }
3238
3239 return 0;
3240 }
3241
3242 static int ext4_commit_super(struct super_block *sb, int sync)
3243 {
3244 struct ext4_super_block *es = EXT4_SB(sb)->s_es;
3245 struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
3246 int error = 0;
3247
3248 if (!sbh)
3249 return error;
3250 if (buffer_write_io_error(sbh)) {
3251 /*
3252 * Oh, dear. A previous attempt to write the
3253 * superblock failed. This could happen because the
3254 * USB device was yanked out. Or it could happen to
3255 * be a transient write error and maybe the block will
3256 * be remapped. Nothing we can do but to retry the
3257 * write and hope for the best.
3258 */
3259 ext4_msg(sb, KERN_ERR, "previous I/O error to "
3260 "superblock detected");
3261 clear_buffer_write_io_error(sbh);
3262 set_buffer_uptodate(sbh);
3263 }
3264 /*
3265 * If the file system is mounted read-only, don't update the
3266 * superblock write time. This avoids updating the superblock
3267 * write time when we are mounting the root file system
3268 * read/only but we need to replay the journal; at that point,
3269 * for people who are east of GMT and who make their clock
3270 * tick in localtime for Windows bug-for-bug compatibility,
3271 * the clock is set in the future, and this will cause e2fsck
3272 * to complain and force a full file system check.
3273 */
3274 if (!(sb->s_flags & MS_RDONLY))
3275 es->s_wtime = cpu_to_le32(get_seconds());
3276 es->s_kbytes_written =
3277 cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
3278 ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
3279 EXT4_SB(sb)->s_sectors_written_start) >> 1));
3280 ext4_free_blocks_count_set(es, percpu_counter_sum_positive(
3281 &EXT4_SB(sb)->s_freeblocks_counter));
3282 es->s_free_inodes_count = cpu_to_le32(percpu_counter_sum_positive(
3283 &EXT4_SB(sb)->s_freeinodes_counter));
3284 sb->s_dirt = 0;
3285 BUFFER_TRACE(sbh, "marking dirty");
3286 mark_buffer_dirty(sbh);
3287 if (sync) {
3288 error = sync_dirty_buffer(sbh);
3289 if (error)
3290 return error;
3291
3292 error = buffer_write_io_error(sbh);
3293 if (error) {
3294 ext4_msg(sb, KERN_ERR, "I/O error while writing "
3295 "superblock");
3296 clear_buffer_write_io_error(sbh);
3297 set_buffer_uptodate(sbh);
3298 }
3299 }
3300 return error;
3301 }
3302
3303 /*
3304 * Have we just finished recovery? If so, and if we are mounting (or
3305 * remounting) the filesystem readonly, then we will end up with a
3306 * consistent fs on disk. Record that fact.
3307 */
3308 static void ext4_mark_recovery_complete(struct super_block *sb,
3309 struct ext4_super_block *es)
3310 {
3311 journal_t *journal = EXT4_SB(sb)->s_journal;
3312
3313 if (!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3314 BUG_ON(journal != NULL);
3315 return;
3316 }
3317 jbd2_journal_lock_updates(journal);
3318 if (jbd2_journal_flush(journal) < 0)
3319 goto out;
3320
3321 if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER) &&
3322 sb->s_flags & MS_RDONLY) {
3323 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3324 ext4_commit_super(sb, 1);
3325 }
3326
3327 out:
3328 jbd2_journal_unlock_updates(journal);
3329 }
3330
3331 /*
3332 * If we are mounting (or read-write remounting) a filesystem whose journal
3333 * has recorded an error from a previous lifetime, move that error to the
3334 * main filesystem now.
3335 */
3336 static void ext4_clear_journal_err(struct super_block *sb,
3337 struct ext4_super_block *es)
3338 {
3339 journal_t *journal;
3340 int j_errno;
3341 const char *errstr;
3342
3343 BUG_ON(!EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL));
3344
3345 journal = EXT4_SB(sb)->s_journal;
3346
3347 /*
3348 * Now check for any error status which may have been recorded in the
3349 * journal by a prior ext4_error() or ext4_abort()
3350 */
3351
3352 j_errno = jbd2_journal_errno(journal);
3353 if (j_errno) {
3354 char nbuf[16];
3355
3356 errstr = ext4_decode_error(sb, j_errno, nbuf);
3357 ext4_warning(sb, __func__, "Filesystem error recorded "
3358 "from previous mount: %s", errstr);
3359 ext4_warning(sb, __func__, "Marking fs in need of "
3360 "filesystem check.");
3361
3362 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
3363 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
3364 ext4_commit_super(sb, 1);
3365
3366 jbd2_journal_clear_err(journal);
3367 }
3368 }
3369
3370 /*
3371 * Force the running and committing transactions to commit,
3372 * and wait on the commit.
3373 */
3374 int ext4_force_commit(struct super_block *sb)
3375 {
3376 journal_t *journal;
3377 int ret = 0;
3378
3379 if (sb->s_flags & MS_RDONLY)
3380 return 0;
3381
3382 journal = EXT4_SB(sb)->s_journal;
3383 if (journal)
3384 ret = ext4_journal_force_commit(journal);
3385
3386 return ret;
3387 }
3388
3389 static void ext4_write_super(struct super_block *sb)
3390 {
3391 lock_super(sb);
3392 ext4_commit_super(sb, 1);
3393 unlock_super(sb);
3394 }
3395
3396 static int ext4_sync_fs(struct super_block *sb, int wait)
3397 {
3398 int ret = 0;
3399 tid_t target;
3400 struct ext4_sb_info *sbi = EXT4_SB(sb);
3401
3402 trace_ext4_sync_fs(sb, wait);
3403 flush_workqueue(sbi->dio_unwritten_wq);
3404 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
3405 if (wait)
3406 jbd2_log_wait_commit(sbi->s_journal, target);
3407 }
3408 return ret;
3409 }
3410
3411 /*
3412 * LVM calls this function before a (read-only) snapshot is created. This
3413 * gives us a chance to flush the journal completely and mark the fs clean.
3414 */
3415 static int ext4_freeze(struct super_block *sb)
3416 {
3417 int error = 0;
3418 journal_t *journal;
3419
3420 if (sb->s_flags & MS_RDONLY)
3421 return 0;
3422
3423 journal = EXT4_SB(sb)->s_journal;
3424
3425 /* Now we set up the journal barrier. */
3426 jbd2_journal_lock_updates(journal);
3427
3428 /*
3429 * Don't clear the needs_recovery flag if we failed to flush
3430 * the journal.
3431 */
3432 error = jbd2_journal_flush(journal);
3433 if (error < 0) {
3434 out:
3435 jbd2_journal_unlock_updates(journal);
3436 return error;
3437 }
3438
3439 /* Journal blocked and flushed, clear needs_recovery flag. */
3440 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3441 error = ext4_commit_super(sb, 1);
3442 if (error)
3443 goto out;
3444 return 0;
3445 }
3446
3447 /*
3448 * Called by LVM after the snapshot is done. We need to reset the RECOVER
3449 * flag here, even though the filesystem is not technically dirty yet.
3450 */
3451 static int ext4_unfreeze(struct super_block *sb)
3452 {
3453 if (sb->s_flags & MS_RDONLY)
3454 return 0;
3455
3456 lock_super(sb);
3457 /* Reset the needs_recovery flag before the fs is unlocked. */
3458 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
3459 ext4_commit_super(sb, 1);
3460 unlock_super(sb);
3461 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3462 return 0;
3463 }
3464
3465 static int ext4_remount(struct super_block *sb, int *flags, char *data)
3466 {
3467 struct ext4_super_block *es;
3468 struct ext4_sb_info *sbi = EXT4_SB(sb);
3469 ext4_fsblk_t n_blocks_count = 0;
3470 unsigned long old_sb_flags;
3471 struct ext4_mount_options old_opts;
3472 ext4_group_t g;
3473 unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3474 int err;
3475 #ifdef CONFIG_QUOTA
3476 int i;
3477 #endif
3478
3479 lock_kernel();
3480
3481 /* Store the original options */
3482 lock_super(sb);
3483 old_sb_flags = sb->s_flags;
3484 old_opts.s_mount_opt = sbi->s_mount_opt;
3485 old_opts.s_resuid = sbi->s_resuid;
3486 old_opts.s_resgid = sbi->s_resgid;
3487 old_opts.s_commit_interval = sbi->s_commit_interval;
3488 old_opts.s_min_batch_time = sbi->s_min_batch_time;
3489 old_opts.s_max_batch_time = sbi->s_max_batch_time;
3490 #ifdef CONFIG_QUOTA
3491 old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
3492 for (i = 0; i < MAXQUOTAS; i++)
3493 old_opts.s_qf_names[i] = sbi->s_qf_names[i];
3494 #endif
3495 if (sbi->s_journal && sbi->s_journal->j_task->io_context)
3496 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
3497
3498 /*
3499 * Allow the "check" option to be passed as a remount option.
3500 */
3501 if (!parse_options(data, sb, NULL, &journal_ioprio,
3502 &n_blocks_count, 1)) {
3503 err = -EINVAL;
3504 goto restore_opts;
3505 }
3506
3507 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
3508 ext4_abort(sb, __func__, "Abort forced by user");
3509
3510 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3511 ((sbi->s_mount_opt & EXT4_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
3512
3513 es = sbi->s_es;
3514
3515 if (sbi->s_journal) {
3516 ext4_init_journal_params(sb, sbi->s_journal);
3517 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3518 }
3519
3520 if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY) ||
3521 n_blocks_count > ext4_blocks_count(es)) {
3522 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
3523 err = -EROFS;
3524 goto restore_opts;
3525 }
3526
3527 if (*flags & MS_RDONLY) {
3528 /*
3529 * First of all, the unconditional stuff we have to do
3530 * to disable replay of the journal when we next remount
3531 */
3532 sb->s_flags |= MS_RDONLY;
3533
3534 /*
3535 * OK, test if we are remounting a valid rw partition
3536 * readonly, and if so set the rdonly flag and then
3537 * mark the partition as valid again.
3538 */
3539 if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
3540 (sbi->s_mount_state & EXT4_VALID_FS))
3541 es->s_state = cpu_to_le16(sbi->s_mount_state);
3542
3543 if (sbi->s_journal)
3544 ext4_mark_recovery_complete(sb, es);
3545 } else {
3546 /* Make sure we can mount this feature set readwrite */
3547 if (!ext4_feature_set_ok(sb, 0)) {
3548 err = -EROFS;
3549 goto restore_opts;
3550 }
3551 /*
3552 * Make sure the group descriptor checksums
3553 * are sane. If they aren't, refuse to remount r/w.
3554 */
3555 for (g = 0; g < sbi->s_groups_count; g++) {
3556 struct ext4_group_desc *gdp =
3557 ext4_get_group_desc(sb, g, NULL);
3558
3559 if (!ext4_group_desc_csum_verify(sbi, g, gdp)) {
3560 ext4_msg(sb, KERN_ERR,
3561 "ext4_remount: Checksum for group %u failed (%u!=%u)",
3562 g, le16_to_cpu(ext4_group_desc_csum(sbi, g, gdp)),
3563 le16_to_cpu(gdp->bg_checksum));
3564 err = -EINVAL;
3565 goto restore_opts;
3566 }
3567 }
3568
3569 /*
3570 * If we have an unprocessed orphan list hanging
3571 * around from a previously readonly bdev mount,
3572 * require a full umount/remount for now.
3573 */
3574 if (es->s_last_orphan) {
3575 ext4_msg(sb, KERN_WARNING, "Couldn't "
3576 "remount RDWR because of unprocessed "
3577 "orphan inode list. Please "
3578 "umount/remount instead");
3579 err = -EINVAL;
3580 goto restore_opts;
3581 }
3582
3583 /*
3584 * Mounting a RDONLY partition read-write, so reread
3585 * and store the current valid flag. (It may have
3586 * been changed by e2fsck since we originally mounted
3587 * the partition.)
3588 */
3589 if (sbi->s_journal)
3590 ext4_clear_journal_err(sb, es);
3591 sbi->s_mount_state = le16_to_cpu(es->s_state);
3592 if ((err = ext4_group_extend(sb, es, n_blocks_count)))
3593 goto restore_opts;
3594 if (!ext4_setup_super(sb, es, 0))
3595 sb->s_flags &= ~MS_RDONLY;
3596 }
3597 }
3598 ext4_setup_system_zone(sb);
3599 if (sbi->s_journal == NULL)
3600 ext4_commit_super(sb, 1);
3601
3602 #ifdef CONFIG_QUOTA
3603 /* Release old quota file names */
3604 for (i = 0; i < MAXQUOTAS; i++)
3605 if (old_opts.s_qf_names[i] &&
3606 old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3607 kfree(old_opts.s_qf_names[i]);
3608 #endif
3609 unlock_super(sb);
3610 unlock_kernel();
3611 return 0;
3612
3613 restore_opts:
3614 sb->s_flags = old_sb_flags;
3615 sbi->s_mount_opt = old_opts.s_mount_opt;
3616 sbi->s_resuid = old_opts.s_resuid;
3617 sbi->s_resgid = old_opts.s_resgid;
3618 sbi->s_commit_interval = old_opts.s_commit_interval;
3619 sbi->s_min_batch_time = old_opts.s_min_batch_time;
3620 sbi->s_max_batch_time = old_opts.s_max_batch_time;
3621 #ifdef CONFIG_QUOTA
3622 sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
3623 for (i = 0; i < MAXQUOTAS; i++) {
3624 if (sbi->s_qf_names[i] &&
3625 old_opts.s_qf_names[i] != sbi->s_qf_names[i])
3626 kfree(sbi->s_qf_names[i]);
3627 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
3628 }
3629 #endif
3630 unlock_super(sb);
3631 unlock_kernel();
3632 return err;
3633 }
3634
3635 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
3636 {
3637 struct super_block *sb = dentry->d_sb;
3638 struct ext4_sb_info *sbi = EXT4_SB(sb);
3639 struct ext4_super_block *es = sbi->s_es;
3640 u64 fsid;
3641
3642 if (test_opt(sb, MINIX_DF)) {
3643 sbi->s_overhead_last = 0;
3644 } else if (sbi->s_blocks_last != ext4_blocks_count(es)) {
3645 ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3646 ext4_fsblk_t overhead = 0;
3647
3648 /*
3649 * Compute the overhead (FS structures). This is constant
3650 * for a given filesystem unless the number of block groups
3651 * changes so we cache the previous value until it does.
3652 */
3653
3654 /*
3655 * All of the blocks before first_data_block are
3656 * overhead
3657 */
3658 overhead = le32_to_cpu(es->s_first_data_block);
3659
3660 /*
3661 * Add the overhead attributed to the superblock and
3662 * block group descriptors. If the sparse superblocks
3663 * feature is turned on, then not all groups have this.
3664 */
3665 for (i = 0; i < ngroups; i++) {
3666 overhead += ext4_bg_has_super(sb, i) +
3667 ext4_bg_num_gdb(sb, i);
3668 cond_resched();
3669 }
3670
3671 /*
3672 * Every block group has an inode bitmap, a block
3673 * bitmap, and an inode table.
3674 */
3675 overhead += ngroups * (2 + sbi->s_itb_per_group);
3676 sbi->s_overhead_last = overhead;
3677 smp_wmb();
3678 sbi->s_blocks_last = ext4_blocks_count(es);
3679 }
3680
3681 buf->f_type = EXT4_SUPER_MAGIC;
3682 buf->f_bsize = sb->s_blocksize;
3683 buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
3684 buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
3685 percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
3686 buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
3687 if (buf->f_bfree < ext4_r_blocks_count(es))
3688 buf->f_bavail = 0;
3689 buf->f_files = le32_to_cpu(es->s_inodes_count);
3690 buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
3691 buf->f_namelen = EXT4_NAME_LEN;
3692 fsid = le64_to_cpup((void *)es->s_uuid) ^
3693 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
3694 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
3695 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
3696
3697 return 0;
3698 }
3699
3700 /* Helper function for writing quotas on sync - we need to start transaction
3701 * before quota file is locked for write. Otherwise the are possible deadlocks:
3702 * Process 1 Process 2
3703 * ext4_create() quota_sync()
3704 * jbd2_journal_start() write_dquot()
3705 * vfs_dq_init() down(dqio_mutex)
3706 * down(dqio_mutex) jbd2_journal_start()
3707 *
3708 */
3709
3710 #ifdef CONFIG_QUOTA
3711
3712 static inline struct inode *dquot_to_inode(struct dquot *dquot)
3713 {
3714 return sb_dqopt(dquot->dq_sb)->files[dquot->dq_type];
3715 }
3716
3717 static int ext4_write_dquot(struct dquot *dquot)
3718 {
3719 int ret, err;
3720 handle_t *handle;
3721 struct inode *inode;
3722
3723 inode = dquot_to_inode(dquot);
3724 handle = ext4_journal_start(inode,
3725 EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
3726 if (IS_ERR(handle))
3727 return PTR_ERR(handle);
3728 ret = dquot_commit(dquot);
3729 err = ext4_journal_stop(handle);
3730 if (!ret)
3731 ret = err;
3732 return ret;
3733 }
3734
3735 static int ext4_acquire_dquot(struct dquot *dquot)
3736 {
3737 int ret, err;
3738 handle_t *handle;
3739
3740 handle = ext4_journal_start(dquot_to_inode(dquot),
3741 EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
3742 if (IS_ERR(handle))
3743 return PTR_ERR(handle);
3744 ret = dquot_acquire(dquot);
3745 err = ext4_journal_stop(handle);
3746 if (!ret)
3747 ret = err;
3748 return ret;
3749 }
3750
3751 static int ext4_release_dquot(struct dquot *dquot)
3752 {
3753 int ret, err;
3754 handle_t *handle;
3755
3756 handle = ext4_journal_start(dquot_to_inode(dquot),
3757 EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
3758 if (IS_ERR(handle)) {
3759 /* Release dquot anyway to avoid endless cycle in dqput() */
3760 dquot_release(dquot);
3761 return PTR_ERR(handle);
3762 }
3763 ret = dquot_release(dquot);
3764 err = ext4_journal_stop(handle);
3765 if (!ret)
3766 ret = err;
3767 return ret;
3768 }
3769
3770 static int ext4_mark_dquot_dirty(struct dquot *dquot)
3771 {
3772 /* Are we journaling quotas? */
3773 if (EXT4_SB(dquot->dq_sb)->s_qf_names[USRQUOTA] ||
3774 EXT4_SB(dquot->dq_sb)->s_qf_names[GRPQUOTA]) {
3775 dquot_mark_dquot_dirty(dquot);
3776 return ext4_write_dquot(dquot);
3777 } else {
3778 return dquot_mark_dquot_dirty(dquot);
3779 }
3780 }
3781
3782 static int ext4_write_info(struct super_block *sb, int type)
3783 {
3784 int ret, err;
3785 handle_t *handle;
3786
3787 /* Data block + inode block */
3788 handle = ext4_journal_start(sb->s_root->d_inode, 2);
3789 if (IS_ERR(handle))
3790 return PTR_ERR(handle);
3791 ret = dquot_commit_info(sb, type);
3792 err = ext4_journal_stop(handle);
3793 if (!ret)
3794 ret = err;
3795 return ret;
3796 }
3797
3798 /*
3799 * Turn on quotas during mount time - we need to find
3800 * the quota file and such...
3801 */
3802 static int ext4_quota_on_mount(struct super_block *sb, int type)
3803 {
3804 return vfs_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
3805 EXT4_SB(sb)->s_jquota_fmt, type);
3806 }
3807
3808 /*
3809 * Standard function to be called on quota_on
3810 */
3811 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
3812 char *name, int remount)
3813 {
3814 int err;
3815 struct path path;
3816
3817 if (!test_opt(sb, QUOTA))
3818 return -EINVAL;
3819 /* When remounting, no checks are needed and in fact, name is NULL */
3820 if (remount)
3821 return vfs_quota_on(sb, type, format_id, name, remount);
3822
3823 err = kern_path(name, LOOKUP_FOLLOW, &path);
3824 if (err)
3825 return err;
3826
3827 /* Quotafile not on the same filesystem? */
3828 if (path.mnt->mnt_sb != sb) {
3829 path_put(&path);
3830 return -EXDEV;
3831 }
3832 /* Journaling quota? */
3833 if (EXT4_SB(sb)->s_qf_names[type]) {
3834 /* Quotafile not in fs root? */
3835 if (path.dentry->d_parent != sb->s_root)
3836 ext4_msg(sb, KERN_WARNING,
3837 "Quota file not on filesystem root. "
3838 "Journaled quota will not work");
3839 }
3840
3841 /*
3842 * When we journal data on quota file, we have to flush journal to see
3843 * all updates to the file when we bypass pagecache...
3844 */
3845 if (EXT4_SB(sb)->s_journal &&
3846 ext4_should_journal_data(path.dentry->d_inode)) {
3847 /*
3848 * We don't need to lock updates but journal_flush() could
3849 * otherwise be livelocked...
3850 */
3851 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
3852 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
3853 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
3854 if (err) {
3855 path_put(&path);
3856 return err;
3857 }
3858 }
3859
3860 err = vfs_quota_on_path(sb, type, format_id, &path);
3861 path_put(&path);
3862 return err;
3863 }
3864
3865 /* Read data from quotafile - avoid pagecache and such because we cannot afford
3866 * acquiring the locks... As quota files are never truncated and quota code
3867 * itself serializes the operations (and noone else should touch the files)
3868 * we don't have to be afraid of races */
3869 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
3870 size_t len, loff_t off)
3871 {
3872 struct inode *inode = sb_dqopt(sb)->files[type];
3873 ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3874 int err = 0;
3875 int offset = off & (sb->s_blocksize - 1);
3876 int tocopy;
3877 size_t toread;
3878 struct buffer_head *bh;
3879 loff_t i_size = i_size_read(inode);
3880
3881 if (off > i_size)
3882 return 0;
3883 if (off+len > i_size)
3884 len = i_size-off;
3885 toread = len;
3886 while (toread > 0) {
3887 tocopy = sb->s_blocksize - offset < toread ?
3888 sb->s_blocksize - offset : toread;
3889 bh = ext4_bread(NULL, inode, blk, 0, &err);
3890 if (err)
3891 return err;
3892 if (!bh) /* A hole? */
3893 memset(data, 0, tocopy);
3894 else
3895 memcpy(data, bh->b_data+offset, tocopy);
3896 brelse(bh);
3897 offset = 0;
3898 toread -= tocopy;
3899 data += tocopy;
3900 blk++;
3901 }
3902 return len;
3903 }
3904
3905 /* Write to quotafile (we know the transaction is already started and has
3906 * enough credits) */
3907 static ssize_t ext4_quota_write(struct super_block *sb, int type,
3908 const char *data, size_t len, loff_t off)
3909 {
3910 struct inode *inode = sb_dqopt(sb)->files[type];
3911 ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
3912 int err = 0;
3913 int offset = off & (sb->s_blocksize - 1);
3914 int tocopy;
3915 int journal_quota = EXT4_SB(sb)->s_qf_names[type] != NULL;
3916 size_t towrite = len;
3917 struct buffer_head *bh;
3918 handle_t *handle = journal_current_handle();
3919
3920 if (EXT4_SB(sb)->s_journal && !handle) {
3921 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
3922 " cancelled because transaction is not started",
3923 (unsigned long long)off, (unsigned long long)len);
3924 return -EIO;
3925 }
3926 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
3927 while (towrite > 0) {
3928 tocopy = sb->s_blocksize - offset < towrite ?
3929 sb->s_blocksize - offset : towrite;
3930 bh = ext4_bread(handle, inode, blk, 1, &err);
3931 if (!bh)
3932 goto out;
3933 if (journal_quota) {
3934 err = ext4_journal_get_write_access(handle, bh);
3935 if (err) {
3936 brelse(bh);
3937 goto out;
3938 }
3939 }
3940 lock_buffer(bh);
3941 memcpy(bh->b_data+offset, data, tocopy);
3942 flush_dcache_page(bh->b_page);
3943 unlock_buffer(bh);
3944 if (journal_quota)
3945 err = ext4_handle_dirty_metadata(handle, NULL, bh);
3946 else {
3947 /* Always do at least ordered writes for quotas */
3948 err = ext4_jbd2_file_inode(handle, inode);
3949 mark_buffer_dirty(bh);
3950 }
3951 brelse(bh);
3952 if (err)
3953 goto out;
3954 offset = 0;
3955 towrite -= tocopy;
3956 data += tocopy;
3957 blk++;
3958 }
3959 out:
3960 if (len == towrite) {
3961 mutex_unlock(&inode->i_mutex);
3962 return err;
3963 }
3964 if (inode->i_size < off+len-towrite) {
3965 i_size_write(inode, off+len-towrite);
3966 EXT4_I(inode)->i_disksize = inode->i_size;
3967 }
3968 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
3969 ext4_mark_inode_dirty(handle, inode);
3970 mutex_unlock(&inode->i_mutex);
3971 return len - towrite;
3972 }
3973
3974 #endif
3975
3976 static int ext4_get_sb(struct file_system_type *fs_type, int flags,
3977 const char *dev_name, void *data, struct vfsmount *mnt)
3978 {
3979 return get_sb_bdev(fs_type, flags, dev_name, data, ext4_fill_super,mnt);
3980 }
3981
3982 #if !defined(CONTIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
3983 static struct file_system_type ext2_fs_type = {
3984 .owner = THIS_MODULE,
3985 .name = "ext2",
3986 .get_sb = ext4_get_sb,
3987 .kill_sb = kill_block_super,
3988 .fs_flags = FS_REQUIRES_DEV,
3989 };
3990
3991 static inline void register_as_ext2(void)
3992 {
3993 int err = register_filesystem(&ext2_fs_type);
3994 if (err)
3995 printk(KERN_WARNING
3996 "EXT4-fs: Unable to register as ext2 (%d)\n", err);
3997 }
3998
3999 static inline void unregister_as_ext2(void)
4000 {
4001 unregister_filesystem(&ext2_fs_type);
4002 }
4003 #else
4004 static inline void register_as_ext2(void) { }
4005 static inline void unregister_as_ext2(void) { }
4006 #endif
4007
4008 #if !defined(CONTIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
4009 static struct file_system_type ext3_fs_type = {
4010 .owner = THIS_MODULE,
4011 .name = "ext3",
4012 .get_sb = ext4_get_sb,
4013 .kill_sb = kill_block_super,
4014 .fs_flags = FS_REQUIRES_DEV,
4015 };
4016
4017 static inline void register_as_ext3(void)
4018 {
4019 int err = register_filesystem(&ext3_fs_type);
4020 if (err)
4021 printk(KERN_WARNING
4022 "EXT4-fs: Unable to register as ext3 (%d)\n", err);
4023 }
4024
4025 static inline void unregister_as_ext3(void)
4026 {
4027 unregister_filesystem(&ext3_fs_type);
4028 }
4029 #else
4030 static inline void register_as_ext3(void) { }
4031 static inline void unregister_as_ext3(void) { }
4032 #endif
4033
4034 static struct file_system_type ext4_fs_type = {
4035 .owner = THIS_MODULE,
4036 .name = "ext4",
4037 .get_sb = ext4_get_sb,
4038 .kill_sb = kill_block_super,
4039 .fs_flags = FS_REQUIRES_DEV,
4040 };
4041
4042 static int __init init_ext4_fs(void)
4043 {
4044 int err;
4045
4046 err = init_ext4_system_zone();
4047 if (err)
4048 return err;
4049 ext4_kset = kset_create_and_add("ext4", NULL, fs_kobj);
4050 if (!ext4_kset)
4051 goto out4;
4052 ext4_proc_root = proc_mkdir("fs/ext4", NULL);
4053 err = init_ext4_mballoc();
4054 if (err)
4055 goto out3;
4056
4057 err = init_ext4_xattr();
4058 if (err)
4059 goto out2;
4060 err = init_inodecache();
4061 if (err)
4062 goto out1;
4063 register_as_ext2();
4064 register_as_ext3();
4065 err = register_filesystem(&ext4_fs_type);
4066 if (err)
4067 goto out;
4068 return 0;
4069 out:
4070 unregister_as_ext2();
4071 unregister_as_ext3();
4072 destroy_inodecache();
4073 out1:
4074 exit_ext4_xattr();
4075 out2:
4076 exit_ext4_mballoc();
4077 out3:
4078 remove_proc_entry("fs/ext4", NULL);
4079 kset_unregister(ext4_kset);
4080 out4:
4081 exit_ext4_system_zone();
4082 return err;
4083 }
4084
4085 static void __exit exit_ext4_fs(void)
4086 {
4087 unregister_as_ext2();
4088 unregister_as_ext3();
4089 unregister_filesystem(&ext4_fs_type);
4090 destroy_inodecache();
4091 exit_ext4_xattr();
4092 exit_ext4_mballoc();
4093 remove_proc_entry("fs/ext4", NULL);
4094 kset_unregister(ext4_kset);
4095 exit_ext4_system_zone();
4096 }
4097
4098 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
4099 MODULE_DESCRIPTION("Fourth Extended Filesystem");
4100 MODULE_LICENSE("GPL");
4101 module_init(init_ext4_fs)
4102 module_exit(exit_ext4_fs)
kernel-based virtual machine