29c80f6d8b274d05f45dda8f0fda0d19d973a31f
[pandora-kernel.git] / fs / ext4 / super.c
1 /*
2  *  linux/fs/ext4/super.c
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/fs/minix/inode.c
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  *
15  *  Big-endian to little-endian byte-swapping/bitmaps by
16  *        David S. Miller (davem@caip.rutgers.edu), 1995
17  */
18
19 #include <linux/module.h>
20 #include <linux/string.h>
21 #include <linux/fs.h>
22 #include <linux/time.h>
23 #include <linux/vmalloc.h>
24 #include <linux/jbd2.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/parser.h>
29 #include <linux/buffer_head.h>
30 #include <linux/exportfs.h>
31 #include <linux/vfs.h>
32 #include <linux/random.h>
33 #include <linux/mount.h>
34 #include <linux/namei.h>
35 #include <linux/quotaops.h>
36 #include <linux/seq_file.h>
37 #include <linux/proc_fs.h>
38 #include <linux/ctype.h>
39 #include <linux/log2.h>
40 #include <linux/crc16.h>
41 #include <asm/uaccess.h>
42
43 #include <linux/kthread.h>
44 #include <linux/freezer.h>
45
46 #include "ext4.h"
47 #include "ext4_jbd2.h"
48 #include "xattr.h"
49 #include "acl.h"
50 #include "mballoc.h"
51
52 #define CREATE_TRACE_POINTS
53 #include <trace/events/ext4.h>
54
55 static struct proc_dir_entry *ext4_proc_root;
56 static struct kset *ext4_kset;
57 struct ext4_lazy_init *ext4_li_info;
58 struct mutex ext4_li_mtx;
59 struct ext4_features *ext4_feat;
60
61 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
62                              unsigned long journal_devnum);
63 static int ext4_commit_super(struct super_block *sb, int sync);
64 static void ext4_mark_recovery_complete(struct super_block *sb,
65                                         struct ext4_super_block *es);
66 static void ext4_clear_journal_err(struct super_block *sb,
67                                    struct ext4_super_block *es);
68 static int ext4_sync_fs(struct super_block *sb, int wait);
69 static const char *ext4_decode_error(struct super_block *sb, int errno,
70                                      char nbuf[16]);
71 static int ext4_remount(struct super_block *sb, int *flags, char *data);
72 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
73 static int ext4_unfreeze(struct super_block *sb);
74 static void ext4_write_super(struct super_block *sb);
75 static int ext4_freeze(struct super_block *sb);
76 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
77                        const char *dev_name, void *data);
78 static void ext4_destroy_lazyinit_thread(void);
79 static void ext4_unregister_li_request(struct super_block *sb);
80
81 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
82 static struct file_system_type ext3_fs_type = {
83         .owner          = THIS_MODULE,
84         .name           = "ext3",
85         .mount          = ext4_mount,
86         .kill_sb        = kill_block_super,
87         .fs_flags       = FS_REQUIRES_DEV,
88 };
89 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
90 #else
91 #define IS_EXT3_SB(sb) (0)
92 #endif
93
94 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
95                                struct ext4_group_desc *bg)
96 {
97         return le32_to_cpu(bg->bg_block_bitmap_lo) |
98                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
99                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
100 }
101
102 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
103                                struct ext4_group_desc *bg)
104 {
105         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
106                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
107                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
108 }
109
110 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
111                               struct ext4_group_desc *bg)
112 {
113         return le32_to_cpu(bg->bg_inode_table_lo) |
114                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
115                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
116 }
117
118 __u32 ext4_free_blks_count(struct super_block *sb,
119                               struct ext4_group_desc *bg)
120 {
121         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
122                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
123                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
124 }
125
126 __u32 ext4_free_inodes_count(struct super_block *sb,
127                               struct ext4_group_desc *bg)
128 {
129         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
130                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
131                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
132 }
133
134 __u32 ext4_used_dirs_count(struct super_block *sb,
135                               struct ext4_group_desc *bg)
136 {
137         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
138                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
139                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
140 }
141
142 __u32 ext4_itable_unused_count(struct super_block *sb,
143                               struct ext4_group_desc *bg)
144 {
145         return le16_to_cpu(bg->bg_itable_unused_lo) |
146                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
147                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
148 }
149
150 void ext4_block_bitmap_set(struct super_block *sb,
151                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
152 {
153         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
154         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
155                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
156 }
157
158 void ext4_inode_bitmap_set(struct super_block *sb,
159                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
160 {
161         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
162         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
163                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
164 }
165
166 void ext4_inode_table_set(struct super_block *sb,
167                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
168 {
169         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
170         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
171                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
172 }
173
174 void ext4_free_blks_set(struct super_block *sb,
175                           struct ext4_group_desc *bg, __u32 count)
176 {
177         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
178         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
179                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
180 }
181
182 void ext4_free_inodes_set(struct super_block *sb,
183                           struct ext4_group_desc *bg, __u32 count)
184 {
185         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
186         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
187                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
188 }
189
190 void ext4_used_dirs_set(struct super_block *sb,
191                           struct ext4_group_desc *bg, __u32 count)
192 {
193         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
194         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
195                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
196 }
197
198 void ext4_itable_unused_set(struct super_block *sb,
199                           struct ext4_group_desc *bg, __u32 count)
200 {
201         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
202         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
203                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
204 }
205
206
207 /* Just increment the non-pointer handle value */
208 static handle_t *ext4_get_nojournal(void)
209 {
210         handle_t *handle = current->journal_info;
211         unsigned long ref_cnt = (unsigned long)handle;
212
213         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
214
215         ref_cnt++;
216         handle = (handle_t *)ref_cnt;
217
218         current->journal_info = handle;
219         return handle;
220 }
221
222
223 /* Decrement the non-pointer handle value */
224 static void ext4_put_nojournal(handle_t *handle)
225 {
226         unsigned long ref_cnt = (unsigned long)handle;
227
228         BUG_ON(ref_cnt == 0);
229
230         ref_cnt--;
231         handle = (handle_t *)ref_cnt;
232
233         current->journal_info = handle;
234 }
235
236 /*
237  * Wrappers for jbd2_journal_start/end.
238  *
239  * The only special thing we need to do here is to make sure that all
240  * journal_end calls result in the superblock being marked dirty, so
241  * that sync() will call the filesystem's write_super callback if
242  * appropriate.
243  */
244 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
245 {
246         journal_t *journal;
247
248         if (sb->s_flags & MS_RDONLY)
249                 return ERR_PTR(-EROFS);
250
251         vfs_check_frozen(sb, SB_FREEZE_TRANS);
252         /* Special case here: if the journal has aborted behind our
253          * backs (eg. EIO in the commit thread), then we still need to
254          * take the FS itself readonly cleanly. */
255         journal = EXT4_SB(sb)->s_journal;
256         if (journal) {
257                 if (is_journal_aborted(journal)) {
258                         ext4_abort(sb, "Detected aborted journal");
259                         return ERR_PTR(-EROFS);
260                 }
261                 return jbd2_journal_start(journal, nblocks);
262         }
263         return ext4_get_nojournal();
264 }
265
266 /*
267  * The only special thing we need to do here is to make sure that all
268  * jbd2_journal_stop calls result in the superblock being marked dirty, so
269  * that sync() will call the filesystem's write_super callback if
270  * appropriate.
271  */
272 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
273 {
274         struct super_block *sb;
275         int err;
276         int rc;
277
278         if (!ext4_handle_valid(handle)) {
279                 ext4_put_nojournal(handle);
280                 return 0;
281         }
282         sb = handle->h_transaction->t_journal->j_private;
283         err = handle->h_err;
284         rc = jbd2_journal_stop(handle);
285
286         if (!err)
287                 err = rc;
288         if (err)
289                 __ext4_std_error(sb, where, line, err);
290         return err;
291 }
292
293 void ext4_journal_abort_handle(const char *caller, unsigned int line,
294                                const char *err_fn, struct buffer_head *bh,
295                                handle_t *handle, int err)
296 {
297         char nbuf[16];
298         const char *errstr = ext4_decode_error(NULL, err, nbuf);
299
300         BUG_ON(!ext4_handle_valid(handle));
301
302         if (bh)
303                 BUFFER_TRACE(bh, "abort");
304
305         if (!handle->h_err)
306                 handle->h_err = err;
307
308         if (is_handle_aborted(handle))
309                 return;
310
311         printk(KERN_ERR "%s:%d: aborting transaction: %s in %s\n",
312                caller, line, errstr, err_fn);
313
314         jbd2_journal_abort_handle(handle);
315 }
316
317 static void __save_error_info(struct super_block *sb, const char *func,
318                             unsigned int line)
319 {
320         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
321
322         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
323         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
324         es->s_last_error_time = cpu_to_le32(get_seconds());
325         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
326         es->s_last_error_line = cpu_to_le32(line);
327         if (!es->s_first_error_time) {
328                 es->s_first_error_time = es->s_last_error_time;
329                 strncpy(es->s_first_error_func, func,
330                         sizeof(es->s_first_error_func));
331                 es->s_first_error_line = cpu_to_le32(line);
332                 es->s_first_error_ino = es->s_last_error_ino;
333                 es->s_first_error_block = es->s_last_error_block;
334         }
335         /*
336          * Start the daily error reporting function if it hasn't been
337          * started already
338          */
339         if (!es->s_error_count)
340                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
341         es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
342 }
343
344 static void save_error_info(struct super_block *sb, const char *func,
345                             unsigned int line)
346 {
347         __save_error_info(sb, func, line);
348         ext4_commit_super(sb, 1);
349 }
350
351
352 /* Deal with the reporting of failure conditions on a filesystem such as
353  * inconsistencies detected or read IO failures.
354  *
355  * On ext2, we can store the error state of the filesystem in the
356  * superblock.  That is not possible on ext4, because we may have other
357  * write ordering constraints on the superblock which prevent us from
358  * writing it out straight away; and given that the journal is about to
359  * be aborted, we can't rely on the current, or future, transactions to
360  * write out the superblock safely.
361  *
362  * We'll just use the jbd2_journal_abort() error code to record an error in
363  * the journal instead.  On recovery, the journal will complain about
364  * that error until we've noted it down and cleared it.
365  */
366
367 static void ext4_handle_error(struct super_block *sb)
368 {
369         if (sb->s_flags & MS_RDONLY)
370                 return;
371
372         if (!test_opt(sb, ERRORS_CONT)) {
373                 journal_t *journal = EXT4_SB(sb)->s_journal;
374
375                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
376                 if (journal)
377                         jbd2_journal_abort(journal, -EIO);
378         }
379         if (test_opt(sb, ERRORS_RO)) {
380                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
381                 sb->s_flags |= MS_RDONLY;
382         }
383         if (test_opt(sb, ERRORS_PANIC))
384                 panic("EXT4-fs (device %s): panic forced after error\n",
385                         sb->s_id);
386 }
387
388 void __ext4_error(struct super_block *sb, const char *function,
389                   unsigned int line, const char *fmt, ...)
390 {
391         struct va_format vaf;
392         va_list args;
393
394         va_start(args, fmt);
395         vaf.fmt = fmt;
396         vaf.va = &args;
397         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
398                sb->s_id, function, line, current->comm, &vaf);
399         va_end(args);
400
401         ext4_handle_error(sb);
402 }
403
404 void ext4_error_inode(struct inode *inode, const char *function,
405                       unsigned int line, ext4_fsblk_t block,
406                       const char *fmt, ...)
407 {
408         va_list args;
409         struct va_format vaf;
410         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
411
412         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
413         es->s_last_error_block = cpu_to_le64(block);
414         save_error_info(inode->i_sb, function, line);
415         va_start(args, fmt);
416         vaf.fmt = fmt;
417         vaf.va = &args;
418         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
419                inode->i_sb->s_id, function, line, inode->i_ino);
420         if (block)
421                 printk(KERN_CONT "block %llu: ", block);
422         printk(KERN_CONT "comm %s: %pV\n", current->comm, &vaf);
423         va_end(args);
424
425         ext4_handle_error(inode->i_sb);
426 }
427
428 void ext4_error_file(struct file *file, const char *function,
429                      unsigned int line, ext4_fsblk_t block,
430                      const char *fmt, ...)
431 {
432         va_list args;
433         struct va_format vaf;
434         struct ext4_super_block *es;
435         struct inode *inode = file->f_dentry->d_inode;
436         char pathname[80], *path;
437
438         es = EXT4_SB(inode->i_sb)->s_es;
439         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
440         save_error_info(inode->i_sb, function, line);
441         path = d_path(&(file->f_path), pathname, sizeof(pathname));
442         if (IS_ERR(path))
443                 path = "(unknown)";
444         printk(KERN_CRIT
445                "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
446                inode->i_sb->s_id, function, line, inode->i_ino);
447         if (block)
448                 printk(KERN_CONT "block %llu: ", block);
449         va_start(args, fmt);
450         vaf.fmt = fmt;
451         vaf.va = &args;
452         printk(KERN_CONT "comm %s: path %s: %pV\n", current->comm, path, &vaf);
453         va_end(args);
454
455         ext4_handle_error(inode->i_sb);
456 }
457
458 static const char *ext4_decode_error(struct super_block *sb, int errno,
459                                      char nbuf[16])
460 {
461         char *errstr = NULL;
462
463         switch (errno) {
464         case -EIO:
465                 errstr = "IO failure";
466                 break;
467         case -ENOMEM:
468                 errstr = "Out of memory";
469                 break;
470         case -EROFS:
471                 if (!sb || (EXT4_SB(sb)->s_journal &&
472                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
473                         errstr = "Journal has aborted";
474                 else
475                         errstr = "Readonly filesystem";
476                 break;
477         default:
478                 /* If the caller passed in an extra buffer for unknown
479                  * errors, textualise them now.  Else we just return
480                  * NULL. */
481                 if (nbuf) {
482                         /* Check for truncated error codes... */
483                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
484                                 errstr = nbuf;
485                 }
486                 break;
487         }
488
489         return errstr;
490 }
491
492 /* __ext4_std_error decodes expected errors from journaling functions
493  * automatically and invokes the appropriate error response.  */
494
495 void __ext4_std_error(struct super_block *sb, const char *function,
496                       unsigned int line, int errno)
497 {
498         char nbuf[16];
499         const char *errstr;
500
501         /* Special case: if the error is EROFS, and we're not already
502          * inside a transaction, then there's really no point in logging
503          * an error. */
504         if (errno == -EROFS && journal_current_handle() == NULL &&
505             (sb->s_flags & MS_RDONLY))
506                 return;
507
508         errstr = ext4_decode_error(sb, errno, nbuf);
509         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
510                sb->s_id, function, line, errstr);
511         save_error_info(sb, function, line);
512
513         ext4_handle_error(sb);
514 }
515
516 /*
517  * ext4_abort is a much stronger failure handler than ext4_error.  The
518  * abort function may be used to deal with unrecoverable failures such
519  * as journal IO errors or ENOMEM at a critical moment in log management.
520  *
521  * We unconditionally force the filesystem into an ABORT|READONLY state,
522  * unless the error response on the fs has been set to panic in which
523  * case we take the easy way out and panic immediately.
524  */
525
526 void __ext4_abort(struct super_block *sb, const char *function,
527                 unsigned int line, const char *fmt, ...)
528 {
529         va_list args;
530
531         save_error_info(sb, function, line);
532         va_start(args, fmt);
533         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
534                function, line);
535         vprintk(fmt, args);
536         printk("\n");
537         va_end(args);
538
539         if ((sb->s_flags & MS_RDONLY) == 0) {
540                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
541                 sb->s_flags |= MS_RDONLY;
542                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
543                 if (EXT4_SB(sb)->s_journal)
544                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
545                 save_error_info(sb, function, line);
546         }
547         if (test_opt(sb, ERRORS_PANIC))
548                 panic("EXT4-fs panic from previous error\n");
549 }
550
551 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
552 {
553         struct va_format vaf;
554         va_list args;
555
556         va_start(args, fmt);
557         vaf.fmt = fmt;
558         vaf.va = &args;
559         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
560         va_end(args);
561 }
562
563 void __ext4_warning(struct super_block *sb, const char *function,
564                     unsigned int line, const char *fmt, ...)
565 {
566         struct va_format vaf;
567         va_list args;
568
569         va_start(args, fmt);
570         vaf.fmt = fmt;
571         vaf.va = &args;
572         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
573                sb->s_id, function, line, &vaf);
574         va_end(args);
575 }
576
577 void __ext4_grp_locked_error(const char *function, unsigned int line,
578                              struct super_block *sb, ext4_group_t grp,
579                              unsigned long ino, ext4_fsblk_t block,
580                              const char *fmt, ...)
581 __releases(bitlock)
582 __acquires(bitlock)
583 {
584         struct va_format vaf;
585         va_list args;
586         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
587
588         es->s_last_error_ino = cpu_to_le32(ino);
589         es->s_last_error_block = cpu_to_le64(block);
590         __save_error_info(sb, function, line);
591
592         va_start(args, fmt);
593
594         vaf.fmt = fmt;
595         vaf.va = &args;
596         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u",
597                sb->s_id, function, line, grp);
598         if (ino)
599                 printk(KERN_CONT "inode %lu: ", ino);
600         if (block)
601                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
602         printk(KERN_CONT "%pV\n", &vaf);
603         va_end(args);
604
605         if (test_opt(sb, ERRORS_CONT)) {
606                 ext4_commit_super(sb, 0);
607                 return;
608         }
609
610         ext4_unlock_group(sb, grp);
611         ext4_handle_error(sb);
612         /*
613          * We only get here in the ERRORS_RO case; relocking the group
614          * may be dangerous, but nothing bad will happen since the
615          * filesystem will have already been marked read/only and the
616          * journal has been aborted.  We return 1 as a hint to callers
617          * who might what to use the return value from
618          * ext4_grp_locked_error() to distinguish beween the
619          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
620          * aggressively from the ext4 function in question, with a
621          * more appropriate error code.
622          */
623         ext4_lock_group(sb, grp);
624         return;
625 }
626
627 void ext4_update_dynamic_rev(struct super_block *sb)
628 {
629         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
630
631         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
632                 return;
633
634         ext4_warning(sb,
635                      "updating to rev %d because of new feature flag, "
636                      "running e2fsck is recommended",
637                      EXT4_DYNAMIC_REV);
638
639         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
640         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
641         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
642         /* leave es->s_feature_*compat flags alone */
643         /* es->s_uuid will be set by e2fsck if empty */
644
645         /*
646          * The rest of the superblock fields should be zero, and if not it
647          * means they are likely already in use, so leave them alone.  We
648          * can leave it up to e2fsck to clean up any inconsistencies there.
649          */
650 }
651
652 /*
653  * Open the external journal device
654  */
655 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
656 {
657         struct block_device *bdev;
658         char b[BDEVNAME_SIZE];
659
660         bdev = open_by_devnum(dev, FMODE_READ|FMODE_WRITE);
661         if (IS_ERR(bdev))
662                 goto fail;
663         return bdev;
664
665 fail:
666         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
667                         __bdevname(dev, b), PTR_ERR(bdev));
668         return NULL;
669 }
670
671 /*
672  * Release the journal device
673  */
674 static int ext4_blkdev_put(struct block_device *bdev)
675 {
676         bd_release(bdev);
677         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE);
678 }
679
680 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
681 {
682         struct block_device *bdev;
683         int ret = -ENODEV;
684
685         bdev = sbi->journal_bdev;
686         if (bdev) {
687                 ret = ext4_blkdev_put(bdev);
688                 sbi->journal_bdev = NULL;
689         }
690         return ret;
691 }
692
693 static inline struct inode *orphan_list_entry(struct list_head *l)
694 {
695         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
696 }
697
698 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
699 {
700         struct list_head *l;
701
702         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
703                  le32_to_cpu(sbi->s_es->s_last_orphan));
704
705         printk(KERN_ERR "sb_info orphan list:\n");
706         list_for_each(l, &sbi->s_orphan) {
707                 struct inode *inode = orphan_list_entry(l);
708                 printk(KERN_ERR "  "
709                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
710                        inode->i_sb->s_id, inode->i_ino, inode,
711                        inode->i_mode, inode->i_nlink,
712                        NEXT_ORPHAN(inode));
713         }
714 }
715
716 static void ext4_put_super(struct super_block *sb)
717 {
718         struct ext4_sb_info *sbi = EXT4_SB(sb);
719         struct ext4_super_block *es = sbi->s_es;
720         int i, err;
721
722         ext4_unregister_li_request(sb);
723         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
724
725         flush_workqueue(sbi->dio_unwritten_wq);
726         destroy_workqueue(sbi->dio_unwritten_wq);
727
728         lock_super(sb);
729         if (sb->s_dirt)
730                 ext4_commit_super(sb, 1);
731
732         if (sbi->s_journal) {
733                 err = jbd2_journal_destroy(sbi->s_journal);
734                 sbi->s_journal = NULL;
735                 if (err < 0)
736                         ext4_abort(sb, "Couldn't clean up the journal");
737         }
738
739         del_timer(&sbi->s_err_report);
740         ext4_release_system_zone(sb);
741         ext4_mb_release(sb);
742         ext4_ext_release(sb);
743         ext4_xattr_put_super(sb);
744
745         if (!(sb->s_flags & MS_RDONLY)) {
746                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
747                 es->s_state = cpu_to_le16(sbi->s_mount_state);
748                 ext4_commit_super(sb, 1);
749         }
750         if (sbi->s_proc) {
751                 remove_proc_entry(sb->s_id, ext4_proc_root);
752         }
753         kobject_del(&sbi->s_kobj);
754
755         for (i = 0; i < sbi->s_gdb_count; i++)
756                 brelse(sbi->s_group_desc[i]);
757         kfree(sbi->s_group_desc);
758         if (is_vmalloc_addr(sbi->s_flex_groups))
759                 vfree(sbi->s_flex_groups);
760         else
761                 kfree(sbi->s_flex_groups);
762         percpu_counter_destroy(&sbi->s_freeblocks_counter);
763         percpu_counter_destroy(&sbi->s_freeinodes_counter);
764         percpu_counter_destroy(&sbi->s_dirs_counter);
765         percpu_counter_destroy(&sbi->s_dirtyblocks_counter);
766         brelse(sbi->s_sbh);
767 #ifdef CONFIG_QUOTA
768         for (i = 0; i < MAXQUOTAS; i++)
769                 kfree(sbi->s_qf_names[i]);
770 #endif
771
772         /* Debugging code just in case the in-memory inode orphan list
773          * isn't empty.  The on-disk one can be non-empty if we've
774          * detected an error and taken the fs readonly, but the
775          * in-memory list had better be clean by this point. */
776         if (!list_empty(&sbi->s_orphan))
777                 dump_orphan_list(sb, sbi);
778         J_ASSERT(list_empty(&sbi->s_orphan));
779
780         invalidate_bdev(sb->s_bdev);
781         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
782                 /*
783                  * Invalidate the journal device's buffers.  We don't want them
784                  * floating about in memory - the physical journal device may
785                  * hotswapped, and it breaks the `ro-after' testing code.
786                  */
787                 sync_blockdev(sbi->journal_bdev);
788                 invalidate_bdev(sbi->journal_bdev);
789                 ext4_blkdev_remove(sbi);
790         }
791         sb->s_fs_info = NULL;
792         /*
793          * Now that we are completely done shutting down the
794          * superblock, we need to actually destroy the kobject.
795          */
796         unlock_super(sb);
797         kobject_put(&sbi->s_kobj);
798         wait_for_completion(&sbi->s_kobj_unregister);
799         kfree(sbi->s_blockgroup_lock);
800         kfree(sbi);
801 }
802
803 static struct kmem_cache *ext4_inode_cachep;
804
805 /*
806  * Called inside transaction, so use GFP_NOFS
807  */
808 static struct inode *ext4_alloc_inode(struct super_block *sb)
809 {
810         struct ext4_inode_info *ei;
811
812         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
813         if (!ei)
814                 return NULL;
815
816         ei->vfs_inode.i_version = 1;
817         ei->vfs_inode.i_data.writeback_index = 0;
818         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
819         INIT_LIST_HEAD(&ei->i_prealloc_list);
820         spin_lock_init(&ei->i_prealloc_lock);
821         ei->i_reserved_data_blocks = 0;
822         ei->i_reserved_meta_blocks = 0;
823         ei->i_allocated_meta_blocks = 0;
824         ei->i_da_metadata_calc_len = 0;
825         spin_lock_init(&(ei->i_block_reservation_lock));
826 #ifdef CONFIG_QUOTA
827         ei->i_reserved_quota = 0;
828 #endif
829         ei->jinode = NULL;
830         INIT_LIST_HEAD(&ei->i_completed_io_list);
831         spin_lock_init(&ei->i_completed_io_lock);
832         ei->cur_aio_dio = NULL;
833         ei->i_sync_tid = 0;
834         ei->i_datasync_tid = 0;
835         atomic_set(&ei->i_ioend_count, 0);
836
837         return &ei->vfs_inode;
838 }
839
840 static int ext4_drop_inode(struct inode *inode)
841 {
842         int drop = generic_drop_inode(inode);
843
844         trace_ext4_drop_inode(inode, drop);
845         return drop;
846 }
847
848 static void ext4_i_callback(struct rcu_head *head)
849 {
850         struct inode *inode = container_of(head, struct inode, i_rcu);
851         INIT_LIST_HEAD(&inode->i_dentry);
852         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
853 }
854
855 static void ext4_destroy_inode(struct inode *inode)
856 {
857         ext4_ioend_wait(inode);
858         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
859                 ext4_msg(inode->i_sb, KERN_ERR,
860                          "Inode %lu (%p): orphan list check failed!",
861                          inode->i_ino, EXT4_I(inode));
862                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
863                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
864                                 true);
865                 dump_stack();
866         }
867         call_rcu(&inode->i_rcu, ext4_i_callback);
868 }
869
870 static void init_once(void *foo)
871 {
872         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
873
874         INIT_LIST_HEAD(&ei->i_orphan);
875 #ifdef CONFIG_EXT4_FS_XATTR
876         init_rwsem(&ei->xattr_sem);
877 #endif
878         init_rwsem(&ei->i_data_sem);
879         inode_init_once(&ei->vfs_inode);
880 }
881
882 static int init_inodecache(void)
883 {
884         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
885                                              sizeof(struct ext4_inode_info),
886                                              0, (SLAB_RECLAIM_ACCOUNT|
887                                                 SLAB_MEM_SPREAD),
888                                              init_once);
889         if (ext4_inode_cachep == NULL)
890                 return -ENOMEM;
891         return 0;
892 }
893
894 static void destroy_inodecache(void)
895 {
896         kmem_cache_destroy(ext4_inode_cachep);
897 }
898
899 void ext4_clear_inode(struct inode *inode)
900 {
901         invalidate_inode_buffers(inode);
902         end_writeback(inode);
903         dquot_drop(inode);
904         ext4_discard_preallocations(inode);
905         if (EXT4_I(inode)->jinode) {
906                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
907                                                EXT4_I(inode)->jinode);
908                 jbd2_free_inode(EXT4_I(inode)->jinode);
909                 EXT4_I(inode)->jinode = NULL;
910         }
911 }
912
913 static inline void ext4_show_quota_options(struct seq_file *seq,
914                                            struct super_block *sb)
915 {
916 #if defined(CONFIG_QUOTA)
917         struct ext4_sb_info *sbi = EXT4_SB(sb);
918
919         if (sbi->s_jquota_fmt) {
920                 char *fmtname = "";
921
922                 switch (sbi->s_jquota_fmt) {
923                 case QFMT_VFS_OLD:
924                         fmtname = "vfsold";
925                         break;
926                 case QFMT_VFS_V0:
927                         fmtname = "vfsv0";
928                         break;
929                 case QFMT_VFS_V1:
930                         fmtname = "vfsv1";
931                         break;
932                 }
933                 seq_printf(seq, ",jqfmt=%s", fmtname);
934         }
935
936         if (sbi->s_qf_names[USRQUOTA])
937                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
938
939         if (sbi->s_qf_names[GRPQUOTA])
940                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
941
942         if (test_opt(sb, USRQUOTA))
943                 seq_puts(seq, ",usrquota");
944
945         if (test_opt(sb, GRPQUOTA))
946                 seq_puts(seq, ",grpquota");
947 #endif
948 }
949
950 /*
951  * Show an option if
952  *  - it's set to a non-default value OR
953  *  - if the per-sb default is different from the global default
954  */
955 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
956 {
957         int def_errors;
958         unsigned long def_mount_opts;
959         struct super_block *sb = vfs->mnt_sb;
960         struct ext4_sb_info *sbi = EXT4_SB(sb);
961         struct ext4_super_block *es = sbi->s_es;
962
963         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
964         def_errors     = le16_to_cpu(es->s_errors);
965
966         if (sbi->s_sb_block != 1)
967                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
968         if (test_opt(sb, MINIX_DF))
969                 seq_puts(seq, ",minixdf");
970         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
971                 seq_puts(seq, ",grpid");
972         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
973                 seq_puts(seq, ",nogrpid");
974         if (sbi->s_resuid != EXT4_DEF_RESUID ||
975             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
976                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
977         }
978         if (sbi->s_resgid != EXT4_DEF_RESGID ||
979             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
980                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
981         }
982         if (test_opt(sb, ERRORS_RO)) {
983                 if (def_errors == EXT4_ERRORS_PANIC ||
984                     def_errors == EXT4_ERRORS_CONTINUE) {
985                         seq_puts(seq, ",errors=remount-ro");
986                 }
987         }
988         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
989                 seq_puts(seq, ",errors=continue");
990         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
991                 seq_puts(seq, ",errors=panic");
992         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
993                 seq_puts(seq, ",nouid32");
994         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
995                 seq_puts(seq, ",debug");
996         if (test_opt(sb, OLDALLOC))
997                 seq_puts(seq, ",oldalloc");
998 #ifdef CONFIG_EXT4_FS_XATTR
999         if (test_opt(sb, XATTR_USER) &&
1000                 !(def_mount_opts & EXT4_DEFM_XATTR_USER))
1001                 seq_puts(seq, ",user_xattr");
1002         if (!test_opt(sb, XATTR_USER) &&
1003             (def_mount_opts & EXT4_DEFM_XATTR_USER)) {
1004                 seq_puts(seq, ",nouser_xattr");
1005         }
1006 #endif
1007 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1008         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
1009                 seq_puts(seq, ",acl");
1010         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
1011                 seq_puts(seq, ",noacl");
1012 #endif
1013         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
1014                 seq_printf(seq, ",commit=%u",
1015                            (unsigned) (sbi->s_commit_interval / HZ));
1016         }
1017         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
1018                 seq_printf(seq, ",min_batch_time=%u",
1019                            (unsigned) sbi->s_min_batch_time);
1020         }
1021         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
1022                 seq_printf(seq, ",max_batch_time=%u",
1023                            (unsigned) sbi->s_min_batch_time);
1024         }
1025
1026         /*
1027          * We're changing the default of barrier mount option, so
1028          * let's always display its mount state so it's clear what its
1029          * status is.
1030          */
1031         seq_puts(seq, ",barrier=");
1032         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
1033         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
1034                 seq_puts(seq, ",journal_async_commit");
1035         else if (test_opt(sb, JOURNAL_CHECKSUM))
1036                 seq_puts(seq, ",journal_checksum");
1037         if (test_opt(sb, I_VERSION))
1038                 seq_puts(seq, ",i_version");
1039         if (!test_opt(sb, DELALLOC) &&
1040             !(def_mount_opts & EXT4_DEFM_NODELALLOC))
1041                 seq_puts(seq, ",nodelalloc");
1042
1043         if (test_opt(sb, MBLK_IO_SUBMIT))
1044                 seq_puts(seq, ",mblk_io_submit");
1045         if (sbi->s_stripe)
1046                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
1047         /*
1048          * journal mode get enabled in different ways
1049          * So just print the value even if we didn't specify it
1050          */
1051         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1052                 seq_puts(seq, ",data=journal");
1053         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1054                 seq_puts(seq, ",data=ordered");
1055         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1056                 seq_puts(seq, ",data=writeback");
1057
1058         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1059                 seq_printf(seq, ",inode_readahead_blks=%u",
1060                            sbi->s_inode_readahead_blks);
1061
1062         if (test_opt(sb, DATA_ERR_ABORT))
1063                 seq_puts(seq, ",data_err=abort");
1064
1065         if (test_opt(sb, NO_AUTO_DA_ALLOC))
1066                 seq_puts(seq, ",noauto_da_alloc");
1067
1068         if (test_opt(sb, DISCARD) && !(def_mount_opts & EXT4_DEFM_DISCARD))
1069                 seq_puts(seq, ",discard");
1070
1071         if (test_opt(sb, NOLOAD))
1072                 seq_puts(seq, ",norecovery");
1073
1074         if (test_opt(sb, DIOREAD_NOLOCK))
1075                 seq_puts(seq, ",dioread_nolock");
1076
1077         if (test_opt(sb, BLOCK_VALIDITY) &&
1078             !(def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY))
1079                 seq_puts(seq, ",block_validity");
1080
1081         if (!test_opt(sb, INIT_INODE_TABLE))
1082                 seq_puts(seq, ",noinit_inode_table");
1083         else if (sbi->s_li_wait_mult)
1084                 seq_printf(seq, ",init_inode_table=%u",
1085                            (unsigned) sbi->s_li_wait_mult);
1086
1087         ext4_show_quota_options(seq, sb);
1088
1089         return 0;
1090 }
1091
1092 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1093                                         u64 ino, u32 generation)
1094 {
1095         struct inode *inode;
1096
1097         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1098                 return ERR_PTR(-ESTALE);
1099         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1100                 return ERR_PTR(-ESTALE);
1101
1102         /* iget isn't really right if the inode is currently unallocated!!
1103          *
1104          * ext4_read_inode will return a bad_inode if the inode had been
1105          * deleted, so we should be safe.
1106          *
1107          * Currently we don't know the generation for parent directory, so
1108          * a generation of 0 means "accept any"
1109          */
1110         inode = ext4_iget(sb, ino);
1111         if (IS_ERR(inode))
1112                 return ERR_CAST(inode);
1113         if (generation && inode->i_generation != generation) {
1114                 iput(inode);
1115                 return ERR_PTR(-ESTALE);
1116         }
1117
1118         return inode;
1119 }
1120
1121 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1122                                         int fh_len, int fh_type)
1123 {
1124         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1125                                     ext4_nfs_get_inode);
1126 }
1127
1128 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1129                                         int fh_len, int fh_type)
1130 {
1131         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1132                                     ext4_nfs_get_inode);
1133 }
1134
1135 /*
1136  * Try to release metadata pages (indirect blocks, directories) which are
1137  * mapped via the block device.  Since these pages could have journal heads
1138  * which would prevent try_to_free_buffers() from freeing them, we must use
1139  * jbd2 layer's try_to_free_buffers() function to release them.
1140  */
1141 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1142                                  gfp_t wait)
1143 {
1144         journal_t *journal = EXT4_SB(sb)->s_journal;
1145
1146         WARN_ON(PageChecked(page));
1147         if (!page_has_buffers(page))
1148                 return 0;
1149         if (journal)
1150                 return jbd2_journal_try_to_free_buffers(journal, page,
1151                                                         wait & ~__GFP_WAIT);
1152         return try_to_free_buffers(page);
1153 }
1154
1155 #ifdef CONFIG_QUOTA
1156 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1157 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1158
1159 static int ext4_write_dquot(struct dquot *dquot);
1160 static int ext4_acquire_dquot(struct dquot *dquot);
1161 static int ext4_release_dquot(struct dquot *dquot);
1162 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1163 static int ext4_write_info(struct super_block *sb, int type);
1164 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1165                                 char *path);
1166 static int ext4_quota_off(struct super_block *sb, int type);
1167 static int ext4_quota_on_mount(struct super_block *sb, int type);
1168 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1169                                size_t len, loff_t off);
1170 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1171                                 const char *data, size_t len, loff_t off);
1172
1173 static const struct dquot_operations ext4_quota_operations = {
1174 #ifdef CONFIG_QUOTA
1175         .get_reserved_space = ext4_get_reserved_space,
1176 #endif
1177         .write_dquot    = ext4_write_dquot,
1178         .acquire_dquot  = ext4_acquire_dquot,
1179         .release_dquot  = ext4_release_dquot,
1180         .mark_dirty     = ext4_mark_dquot_dirty,
1181         .write_info     = ext4_write_info,
1182         .alloc_dquot    = dquot_alloc,
1183         .destroy_dquot  = dquot_destroy,
1184 };
1185
1186 static const struct quotactl_ops ext4_qctl_operations = {
1187         .quota_on       = ext4_quota_on,
1188         .quota_off      = ext4_quota_off,
1189         .quota_sync     = dquot_quota_sync,
1190         .get_info       = dquot_get_dqinfo,
1191         .set_info       = dquot_set_dqinfo,
1192         .get_dqblk      = dquot_get_dqblk,
1193         .set_dqblk      = dquot_set_dqblk
1194 };
1195 #endif
1196
1197 static const struct super_operations ext4_sops = {
1198         .alloc_inode    = ext4_alloc_inode,
1199         .destroy_inode  = ext4_destroy_inode,
1200         .write_inode    = ext4_write_inode,
1201         .dirty_inode    = ext4_dirty_inode,
1202         .drop_inode     = ext4_drop_inode,
1203         .evict_inode    = ext4_evict_inode,
1204         .put_super      = ext4_put_super,
1205         .sync_fs        = ext4_sync_fs,
1206         .freeze_fs      = ext4_freeze,
1207         .unfreeze_fs    = ext4_unfreeze,
1208         .statfs         = ext4_statfs,
1209         .remount_fs     = ext4_remount,
1210         .show_options   = ext4_show_options,
1211 #ifdef CONFIG_QUOTA
1212         .quota_read     = ext4_quota_read,
1213         .quota_write    = ext4_quota_write,
1214 #endif
1215         .bdev_try_to_free_page = bdev_try_to_free_page,
1216 };
1217
1218 static const struct super_operations ext4_nojournal_sops = {
1219         .alloc_inode    = ext4_alloc_inode,
1220         .destroy_inode  = ext4_destroy_inode,
1221         .write_inode    = ext4_write_inode,
1222         .dirty_inode    = ext4_dirty_inode,
1223         .drop_inode     = ext4_drop_inode,
1224         .evict_inode    = ext4_evict_inode,
1225         .write_super    = ext4_write_super,
1226         .put_super      = ext4_put_super,
1227         .statfs         = ext4_statfs,
1228         .remount_fs     = ext4_remount,
1229         .show_options   = ext4_show_options,
1230 #ifdef CONFIG_QUOTA
1231         .quota_read     = ext4_quota_read,
1232         .quota_write    = ext4_quota_write,
1233 #endif
1234         .bdev_try_to_free_page = bdev_try_to_free_page,
1235 };
1236
1237 static const struct export_operations ext4_export_ops = {
1238         .fh_to_dentry = ext4_fh_to_dentry,
1239         .fh_to_parent = ext4_fh_to_parent,
1240         .get_parent = ext4_get_parent,
1241 };
1242
1243 enum {
1244         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1245         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1246         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1247         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1248         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1249         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1250         Opt_journal_update, Opt_journal_dev,
1251         Opt_journal_checksum, Opt_journal_async_commit,
1252         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1253         Opt_data_err_abort, Opt_data_err_ignore,
1254         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1255         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1256         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1257         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1258         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1259         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1260         Opt_inode_readahead_blks, Opt_journal_ioprio,
1261         Opt_dioread_nolock, Opt_dioread_lock,
1262         Opt_discard, Opt_nodiscard,
1263         Opt_init_inode_table, Opt_noinit_inode_table,
1264 };
1265
1266 static const match_table_t tokens = {
1267         {Opt_bsd_df, "bsddf"},
1268         {Opt_minix_df, "minixdf"},
1269         {Opt_grpid, "grpid"},
1270         {Opt_grpid, "bsdgroups"},
1271         {Opt_nogrpid, "nogrpid"},
1272         {Opt_nogrpid, "sysvgroups"},
1273         {Opt_resgid, "resgid=%u"},
1274         {Opt_resuid, "resuid=%u"},
1275         {Opt_sb, "sb=%u"},
1276         {Opt_err_cont, "errors=continue"},
1277         {Opt_err_panic, "errors=panic"},
1278         {Opt_err_ro, "errors=remount-ro"},
1279         {Opt_nouid32, "nouid32"},
1280         {Opt_debug, "debug"},
1281         {Opt_oldalloc, "oldalloc"},
1282         {Opt_orlov, "orlov"},
1283         {Opt_user_xattr, "user_xattr"},
1284         {Opt_nouser_xattr, "nouser_xattr"},
1285         {Opt_acl, "acl"},
1286         {Opt_noacl, "noacl"},
1287         {Opt_noload, "noload"},
1288         {Opt_noload, "norecovery"},
1289         {Opt_nobh, "nobh"},
1290         {Opt_bh, "bh"},
1291         {Opt_commit, "commit=%u"},
1292         {Opt_min_batch_time, "min_batch_time=%u"},
1293         {Opt_max_batch_time, "max_batch_time=%u"},
1294         {Opt_journal_update, "journal=update"},
1295         {Opt_journal_dev, "journal_dev=%u"},
1296         {Opt_journal_checksum, "journal_checksum"},
1297         {Opt_journal_async_commit, "journal_async_commit"},
1298         {Opt_abort, "abort"},
1299         {Opt_data_journal, "data=journal"},
1300         {Opt_data_ordered, "data=ordered"},
1301         {Opt_data_writeback, "data=writeback"},
1302         {Opt_data_err_abort, "data_err=abort"},
1303         {Opt_data_err_ignore, "data_err=ignore"},
1304         {Opt_offusrjquota, "usrjquota="},
1305         {Opt_usrjquota, "usrjquota=%s"},
1306         {Opt_offgrpjquota, "grpjquota="},
1307         {Opt_grpjquota, "grpjquota=%s"},
1308         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1309         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1310         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1311         {Opt_grpquota, "grpquota"},
1312         {Opt_noquota, "noquota"},
1313         {Opt_quota, "quota"},
1314         {Opt_usrquota, "usrquota"},
1315         {Opt_barrier, "barrier=%u"},
1316         {Opt_barrier, "barrier"},
1317         {Opt_nobarrier, "nobarrier"},
1318         {Opt_i_version, "i_version"},
1319         {Opt_stripe, "stripe=%u"},
1320         {Opt_resize, "resize"},
1321         {Opt_delalloc, "delalloc"},
1322         {Opt_nodelalloc, "nodelalloc"},
1323         {Opt_mblk_io_submit, "mblk_io_submit"},
1324         {Opt_nomblk_io_submit, "nomblk_io_submit"},
1325         {Opt_block_validity, "block_validity"},
1326         {Opt_noblock_validity, "noblock_validity"},
1327         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1328         {Opt_journal_ioprio, "journal_ioprio=%u"},
1329         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1330         {Opt_auto_da_alloc, "auto_da_alloc"},
1331         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1332         {Opt_dioread_nolock, "dioread_nolock"},
1333         {Opt_dioread_lock, "dioread_lock"},
1334         {Opt_discard, "discard"},
1335         {Opt_nodiscard, "nodiscard"},
1336         {Opt_init_inode_table, "init_itable=%u"},
1337         {Opt_init_inode_table, "init_itable"},
1338         {Opt_noinit_inode_table, "noinit_itable"},
1339         {Opt_err, NULL},
1340 };
1341
1342 static ext4_fsblk_t get_sb_block(void **data)
1343 {
1344         ext4_fsblk_t    sb_block;
1345         char            *options = (char *) *data;
1346
1347         if (!options || strncmp(options, "sb=", 3) != 0)
1348                 return 1;       /* Default location */
1349
1350         options += 3;
1351         /* TODO: use simple_strtoll with >32bit ext4 */
1352         sb_block = simple_strtoul(options, &options, 0);
1353         if (*options && *options != ',') {
1354                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1355                        (char *) *data);
1356                 return 1;
1357         }
1358         if (*options == ',')
1359                 options++;
1360         *data = (void *) options;
1361
1362         return sb_block;
1363 }
1364
1365 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1366 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1367         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1368
1369 #ifdef CONFIG_QUOTA
1370 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1371 {
1372         struct ext4_sb_info *sbi = EXT4_SB(sb);
1373         char *qname;
1374
1375         if (sb_any_quota_loaded(sb) &&
1376                 !sbi->s_qf_names[qtype]) {
1377                 ext4_msg(sb, KERN_ERR,
1378                         "Cannot change journaled "
1379                         "quota options when quota turned on");
1380                 return 0;
1381         }
1382         qname = match_strdup(args);
1383         if (!qname) {
1384                 ext4_msg(sb, KERN_ERR,
1385                         "Not enough memory for storing quotafile name");
1386                 return 0;
1387         }
1388         if (sbi->s_qf_names[qtype] &&
1389                 strcmp(sbi->s_qf_names[qtype], qname)) {
1390                 ext4_msg(sb, KERN_ERR,
1391                         "%s quota file already specified", QTYPE2NAME(qtype));
1392                 kfree(qname);
1393                 return 0;
1394         }
1395         sbi->s_qf_names[qtype] = qname;
1396         if (strchr(sbi->s_qf_names[qtype], '/')) {
1397                 ext4_msg(sb, KERN_ERR,
1398                         "quotafile must be on filesystem root");
1399                 kfree(sbi->s_qf_names[qtype]);
1400                 sbi->s_qf_names[qtype] = NULL;
1401                 return 0;
1402         }
1403         set_opt(sb, QUOTA);
1404         return 1;
1405 }
1406
1407 static int clear_qf_name(struct super_block *sb, int qtype)
1408 {
1409
1410         struct ext4_sb_info *sbi = EXT4_SB(sb);
1411
1412         if (sb_any_quota_loaded(sb) &&
1413                 sbi->s_qf_names[qtype]) {
1414                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1415                         " when quota turned on");
1416                 return 0;
1417         }
1418         /*
1419          * The space will be released later when all options are confirmed
1420          * to be correct
1421          */
1422         sbi->s_qf_names[qtype] = NULL;
1423         return 1;
1424 }
1425 #endif
1426
1427 static int parse_options(char *options, struct super_block *sb,
1428                          unsigned long *journal_devnum,
1429                          unsigned int *journal_ioprio,
1430                          ext4_fsblk_t *n_blocks_count, int is_remount)
1431 {
1432         struct ext4_sb_info *sbi = EXT4_SB(sb);
1433         char *p;
1434         substring_t args[MAX_OPT_ARGS];
1435         int data_opt = 0;
1436         int option;
1437 #ifdef CONFIG_QUOTA
1438         int qfmt;
1439 #endif
1440
1441         if (!options)
1442                 return 1;
1443
1444         while ((p = strsep(&options, ",")) != NULL) {
1445                 int token;
1446                 if (!*p)
1447                         continue;
1448
1449                 /*
1450                  * Initialize args struct so we know whether arg was
1451                  * found; some options take optional arguments.
1452                  */
1453                 args[0].to = args[0].from = 0;
1454                 token = match_token(p, tokens, args);
1455                 switch (token) {
1456                 case Opt_bsd_df:
1457                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1458                         clear_opt(sb, MINIX_DF);
1459                         break;
1460                 case Opt_minix_df:
1461                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1462                         set_opt(sb, MINIX_DF);
1463
1464                         break;
1465                 case Opt_grpid:
1466                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1467                         set_opt(sb, GRPID);
1468
1469                         break;
1470                 case Opt_nogrpid:
1471                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1472                         clear_opt(sb, GRPID);
1473
1474                         break;
1475                 case Opt_resuid:
1476                         if (match_int(&args[0], &option))
1477                                 return 0;
1478                         sbi->s_resuid = option;
1479                         break;
1480                 case Opt_resgid:
1481                         if (match_int(&args[0], &option))
1482                                 return 0;
1483                         sbi->s_resgid = option;
1484                         break;
1485                 case Opt_sb:
1486                         /* handled by get_sb_block() instead of here */
1487                         /* *sb_block = match_int(&args[0]); */
1488                         break;
1489                 case Opt_err_panic:
1490                         clear_opt(sb, ERRORS_CONT);
1491                         clear_opt(sb, ERRORS_RO);
1492                         set_opt(sb, ERRORS_PANIC);
1493                         break;
1494                 case Opt_err_ro:
1495                         clear_opt(sb, ERRORS_CONT);
1496                         clear_opt(sb, ERRORS_PANIC);
1497                         set_opt(sb, ERRORS_RO);
1498                         break;
1499                 case Opt_err_cont:
1500                         clear_opt(sb, ERRORS_RO);
1501                         clear_opt(sb, ERRORS_PANIC);
1502                         set_opt(sb, ERRORS_CONT);
1503                         break;
1504                 case Opt_nouid32:
1505                         set_opt(sb, NO_UID32);
1506                         break;
1507                 case Opt_debug:
1508                         set_opt(sb, DEBUG);
1509                         break;
1510                 case Opt_oldalloc:
1511                         set_opt(sb, OLDALLOC);
1512                         break;
1513                 case Opt_orlov:
1514                         clear_opt(sb, OLDALLOC);
1515                         break;
1516 #ifdef CONFIG_EXT4_FS_XATTR
1517                 case Opt_user_xattr:
1518                         set_opt(sb, XATTR_USER);
1519                         break;
1520                 case Opt_nouser_xattr:
1521                         clear_opt(sb, XATTR_USER);
1522                         break;
1523 #else
1524                 case Opt_user_xattr:
1525                 case Opt_nouser_xattr:
1526                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1527                         break;
1528 #endif
1529 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1530                 case Opt_acl:
1531                         set_opt(sb, POSIX_ACL);
1532                         break;
1533                 case Opt_noacl:
1534                         clear_opt(sb, POSIX_ACL);
1535                         break;
1536 #else
1537                 case Opt_acl:
1538                 case Opt_noacl:
1539                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1540                         break;
1541 #endif
1542                 case Opt_journal_update:
1543                         /* @@@ FIXME */
1544                         /* Eventually we will want to be able to create
1545                            a journal file here.  For now, only allow the
1546                            user to specify an existing inode to be the
1547                            journal file. */
1548                         if (is_remount) {
1549                                 ext4_msg(sb, KERN_ERR,
1550                                          "Cannot specify journal on remount");
1551                                 return 0;
1552                         }
1553                         set_opt(sb, UPDATE_JOURNAL);
1554                         break;
1555                 case Opt_journal_dev:
1556                         if (is_remount) {
1557                                 ext4_msg(sb, KERN_ERR,
1558                                         "Cannot specify journal on remount");
1559                                 return 0;
1560                         }
1561                         if (match_int(&args[0], &option))
1562                                 return 0;
1563                         *journal_devnum = option;
1564                         break;
1565                 case Opt_journal_checksum:
1566                         set_opt(sb, JOURNAL_CHECKSUM);
1567                         break;
1568                 case Opt_journal_async_commit:
1569                         set_opt(sb, JOURNAL_ASYNC_COMMIT);
1570                         set_opt(sb, JOURNAL_CHECKSUM);
1571                         break;
1572                 case Opt_noload:
1573                         set_opt(sb, NOLOAD);
1574                         break;
1575                 case Opt_commit:
1576                         if (match_int(&args[0], &option))
1577                                 return 0;
1578                         if (option < 0)
1579                                 return 0;
1580                         if (option == 0)
1581                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1582                         sbi->s_commit_interval = HZ * option;
1583                         break;
1584                 case Opt_max_batch_time:
1585                         if (match_int(&args[0], &option))
1586                                 return 0;
1587                         if (option < 0)
1588                                 return 0;
1589                         if (option == 0)
1590                                 option = EXT4_DEF_MAX_BATCH_TIME;
1591                         sbi->s_max_batch_time = option;
1592                         break;
1593                 case Opt_min_batch_time:
1594                         if (match_int(&args[0], &option))
1595                                 return 0;
1596                         if (option < 0)
1597                                 return 0;
1598                         sbi->s_min_batch_time = option;
1599                         break;
1600                 case Opt_data_journal:
1601                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1602                         goto datacheck;
1603                 case Opt_data_ordered:
1604                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1605                         goto datacheck;
1606                 case Opt_data_writeback:
1607                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1608                 datacheck:
1609                         if (is_remount) {
1610                                 if (test_opt(sb, DATA_FLAGS) != data_opt) {
1611                                         ext4_msg(sb, KERN_ERR,
1612                                                 "Cannot change data mode on remount");
1613                                         return 0;
1614                                 }
1615                         } else {
1616                                 clear_opt(sb, DATA_FLAGS);
1617                                 sbi->s_mount_opt |= data_opt;
1618                         }
1619                         break;
1620                 case Opt_data_err_abort:
1621                         set_opt(sb, DATA_ERR_ABORT);
1622                         break;
1623                 case Opt_data_err_ignore:
1624                         clear_opt(sb, DATA_ERR_ABORT);
1625                         break;
1626 #ifdef CONFIG_QUOTA
1627                 case Opt_usrjquota:
1628                         if (!set_qf_name(sb, USRQUOTA, &args[0]))
1629                                 return 0;
1630                         break;
1631                 case Opt_grpjquota:
1632                         if (!set_qf_name(sb, GRPQUOTA, &args[0]))
1633                                 return 0;
1634                         break;
1635                 case Opt_offusrjquota:
1636                         if (!clear_qf_name(sb, USRQUOTA))
1637                                 return 0;
1638                         break;
1639                 case Opt_offgrpjquota:
1640                         if (!clear_qf_name(sb, GRPQUOTA))
1641                                 return 0;
1642                         break;
1643
1644                 case Opt_jqfmt_vfsold:
1645                         qfmt = QFMT_VFS_OLD;
1646                         goto set_qf_format;
1647                 case Opt_jqfmt_vfsv0:
1648                         qfmt = QFMT_VFS_V0;
1649                         goto set_qf_format;
1650                 case Opt_jqfmt_vfsv1:
1651                         qfmt = QFMT_VFS_V1;
1652 set_qf_format:
1653                         if (sb_any_quota_loaded(sb) &&
1654                             sbi->s_jquota_fmt != qfmt) {
1655                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1656                                         "journaled quota options when "
1657                                         "quota turned on");
1658                                 return 0;
1659                         }
1660                         sbi->s_jquota_fmt = qfmt;
1661                         break;
1662                 case Opt_quota:
1663                 case Opt_usrquota:
1664                         set_opt(sb, QUOTA);
1665                         set_opt(sb, USRQUOTA);
1666                         break;
1667                 case Opt_grpquota:
1668                         set_opt(sb, QUOTA);
1669                         set_opt(sb, GRPQUOTA);
1670                         break;
1671                 case Opt_noquota:
1672                         if (sb_any_quota_loaded(sb)) {
1673                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1674                                         "options when quota turned on");
1675                                 return 0;
1676                         }
1677                         clear_opt(sb, QUOTA);
1678                         clear_opt(sb, USRQUOTA);
1679                         clear_opt(sb, GRPQUOTA);
1680                         break;
1681 #else
1682                 case Opt_quota:
1683                 case Opt_usrquota:
1684                 case Opt_grpquota:
1685                         ext4_msg(sb, KERN_ERR,
1686                                 "quota options not supported");
1687                         break;
1688                 case Opt_usrjquota:
1689                 case Opt_grpjquota:
1690                 case Opt_offusrjquota:
1691                 case Opt_offgrpjquota:
1692                 case Opt_jqfmt_vfsold:
1693                 case Opt_jqfmt_vfsv0:
1694                 case Opt_jqfmt_vfsv1:
1695                         ext4_msg(sb, KERN_ERR,
1696                                 "journaled quota options not supported");
1697                         break;
1698                 case Opt_noquota:
1699                         break;
1700 #endif
1701                 case Opt_abort:
1702                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1703                         break;
1704                 case Opt_nobarrier:
1705                         clear_opt(sb, BARRIER);
1706                         break;
1707                 case Opt_barrier:
1708                         if (args[0].from) {
1709                                 if (match_int(&args[0], &option))
1710                                         return 0;
1711                         } else
1712                                 option = 1;     /* No argument, default to 1 */
1713                         if (option)
1714                                 set_opt(sb, BARRIER);
1715                         else
1716                                 clear_opt(sb, BARRIER);
1717                         break;
1718                 case Opt_ignore:
1719                         break;
1720                 case Opt_resize:
1721                         if (!is_remount) {
1722                                 ext4_msg(sb, KERN_ERR,
1723                                         "resize option only available "
1724                                         "for remount");
1725                                 return 0;
1726                         }
1727                         if (match_int(&args[0], &option) != 0)
1728                                 return 0;
1729                         *n_blocks_count = option;
1730                         break;
1731                 case Opt_nobh:
1732                         ext4_msg(sb, KERN_WARNING,
1733                                  "Ignoring deprecated nobh option");
1734                         break;
1735                 case Opt_bh:
1736                         ext4_msg(sb, KERN_WARNING,
1737                                  "Ignoring deprecated bh option");
1738                         break;
1739                 case Opt_i_version:
1740                         set_opt(sb, I_VERSION);
1741                         sb->s_flags |= MS_I_VERSION;
1742                         break;
1743                 case Opt_nodelalloc:
1744                         clear_opt(sb, DELALLOC);
1745                         break;
1746                 case Opt_mblk_io_submit:
1747                         set_opt(sb, MBLK_IO_SUBMIT);
1748                         break;
1749                 case Opt_nomblk_io_submit:
1750                         clear_opt(sb, MBLK_IO_SUBMIT);
1751                         break;
1752                 case Opt_stripe:
1753                         if (match_int(&args[0], &option))
1754                                 return 0;
1755                         if (option < 0)
1756                                 return 0;
1757                         sbi->s_stripe = option;
1758                         break;
1759                 case Opt_delalloc:
1760                         set_opt(sb, DELALLOC);
1761                         break;
1762                 case Opt_block_validity:
1763                         set_opt(sb, BLOCK_VALIDITY);
1764                         break;
1765                 case Opt_noblock_validity:
1766                         clear_opt(sb, BLOCK_VALIDITY);
1767                         break;
1768                 case Opt_inode_readahead_blks:
1769                         if (match_int(&args[0], &option))
1770                                 return 0;
1771                         if (option < 0 || option > (1 << 30))
1772                                 return 0;
1773                         if (!is_power_of_2(option)) {
1774                                 ext4_msg(sb, KERN_ERR,
1775                                          "EXT4-fs: inode_readahead_blks"
1776                                          " must be a power of 2");
1777                                 return 0;
1778                         }
1779                         sbi->s_inode_readahead_blks = option;
1780                         break;
1781                 case Opt_journal_ioprio:
1782                         if (match_int(&args[0], &option))
1783                                 return 0;
1784                         if (option < 0 || option > 7)
1785                                 break;
1786                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1787                                                             option);
1788                         break;
1789                 case Opt_noauto_da_alloc:
1790                         set_opt(sb, NO_AUTO_DA_ALLOC);
1791                         break;
1792                 case Opt_auto_da_alloc:
1793                         if (args[0].from) {
1794                                 if (match_int(&args[0], &option))
1795                                         return 0;
1796                         } else
1797                                 option = 1;     /* No argument, default to 1 */
1798                         if (option)
1799                                 clear_opt(sb, NO_AUTO_DA_ALLOC);
1800                         else
1801                                 set_opt(sb,NO_AUTO_DA_ALLOC);
1802                         break;
1803                 case Opt_discard:
1804                         set_opt(sb, DISCARD);
1805                         break;
1806                 case Opt_nodiscard:
1807                         clear_opt(sb, DISCARD);
1808                         break;
1809                 case Opt_dioread_nolock:
1810                         set_opt(sb, DIOREAD_NOLOCK);
1811                         break;
1812                 case Opt_dioread_lock:
1813                         clear_opt(sb, DIOREAD_NOLOCK);
1814                         break;
1815                 case Opt_init_inode_table:
1816                         set_opt(sb, INIT_INODE_TABLE);
1817                         if (args[0].from) {
1818                                 if (match_int(&args[0], &option))
1819                                         return 0;
1820                         } else
1821                                 option = EXT4_DEF_LI_WAIT_MULT;
1822                         if (option < 0)
1823                                 return 0;
1824                         sbi->s_li_wait_mult = option;
1825                         break;
1826                 case Opt_noinit_inode_table:
1827                         clear_opt(sb, INIT_INODE_TABLE);
1828                         break;
1829                 default:
1830                         ext4_msg(sb, KERN_ERR,
1831                                "Unrecognized mount option \"%s\" "
1832                                "or missing value", p);
1833                         return 0;
1834                 }
1835         }
1836 #ifdef CONFIG_QUOTA
1837         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1838                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1839                         clear_opt(sb, USRQUOTA);
1840
1841                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1842                         clear_opt(sb, GRPQUOTA);
1843
1844                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1845                         ext4_msg(sb, KERN_ERR, "old and new quota "
1846                                         "format mixing");
1847                         return 0;
1848                 }
1849
1850                 if (!sbi->s_jquota_fmt) {
1851                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1852                                         "not specified");
1853                         return 0;
1854                 }
1855         } else {
1856                 if (sbi->s_jquota_fmt) {
1857                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1858                                         "specified with no journaling "
1859                                         "enabled");
1860                         return 0;
1861                 }
1862         }
1863 #endif
1864         return 1;
1865 }
1866
1867 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1868                             int read_only)
1869 {
1870         struct ext4_sb_info *sbi = EXT4_SB(sb);
1871         int res = 0;
1872
1873         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1874                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1875                          "forcing read-only mode");
1876                 res = MS_RDONLY;
1877         }
1878         if (read_only)
1879                 return res;
1880         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1881                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1882                          "running e2fsck is recommended");
1883         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1884                 ext4_msg(sb, KERN_WARNING,
1885                          "warning: mounting fs with errors, "
1886                          "running e2fsck is recommended");
1887         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
1888                  le16_to_cpu(es->s_mnt_count) >=
1889                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1890                 ext4_msg(sb, KERN_WARNING,
1891                          "warning: maximal mount count reached, "
1892                          "running e2fsck is recommended");
1893         else if (le32_to_cpu(es->s_checkinterval) &&
1894                 (le32_to_cpu(es->s_lastcheck) +
1895                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1896                 ext4_msg(sb, KERN_WARNING,
1897                          "warning: checktime reached, "
1898                          "running e2fsck is recommended");
1899         if (!sbi->s_journal)
1900                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1901         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1902                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1903         le16_add_cpu(&es->s_mnt_count, 1);
1904         es->s_mtime = cpu_to_le32(get_seconds());
1905         ext4_update_dynamic_rev(sb);
1906         if (sbi->s_journal)
1907                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1908
1909         ext4_commit_super(sb, 1);
1910         if (test_opt(sb, DEBUG))
1911                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1912                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1913                         sb->s_blocksize,
1914                         sbi->s_groups_count,
1915                         EXT4_BLOCKS_PER_GROUP(sb),
1916                         EXT4_INODES_PER_GROUP(sb),
1917                         sbi->s_mount_opt, sbi->s_mount_opt2);
1918
1919         return res;
1920 }
1921
1922 static int ext4_fill_flex_info(struct super_block *sb)
1923 {
1924         struct ext4_sb_info *sbi = EXT4_SB(sb);
1925         struct ext4_group_desc *gdp = NULL;
1926         ext4_group_t flex_group_count;
1927         ext4_group_t flex_group;
1928         int groups_per_flex = 0;
1929         size_t size;
1930         int i;
1931
1932         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1933         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1934
1935         if (groups_per_flex < 2) {
1936                 sbi->s_log_groups_per_flex = 0;
1937                 return 1;
1938         }
1939
1940         /* We allocate both existing and potentially added groups */
1941         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1942                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1943                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1944         size = flex_group_count * sizeof(struct flex_groups);
1945         sbi->s_flex_groups = kzalloc(size, GFP_KERNEL);
1946         if (sbi->s_flex_groups == NULL) {
1947                 sbi->s_flex_groups = vzalloc(size);
1948                 if (sbi->s_flex_groups == NULL) {
1949                         ext4_msg(sb, KERN_ERR,
1950                                  "not enough memory for %u flex groups",
1951                                  flex_group_count);
1952                         goto failed;
1953                 }
1954         }
1955
1956         for (i = 0; i < sbi->s_groups_count; i++) {
1957                 gdp = ext4_get_group_desc(sb, i, NULL);
1958
1959                 flex_group = ext4_flex_group(sbi, i);
1960                 atomic_add(ext4_free_inodes_count(sb, gdp),
1961                            &sbi->s_flex_groups[flex_group].free_inodes);
1962                 atomic_add(ext4_free_blks_count(sb, gdp),
1963                            &sbi->s_flex_groups[flex_group].free_blocks);
1964                 atomic_add(ext4_used_dirs_count(sb, gdp),
1965                            &sbi->s_flex_groups[flex_group].used_dirs);
1966         }
1967
1968         return 1;
1969 failed:
1970         return 0;
1971 }
1972
1973 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1974                             struct ext4_group_desc *gdp)
1975 {
1976         __u16 crc = 0;
1977
1978         if (sbi->s_es->s_feature_ro_compat &
1979             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1980                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1981                 __le32 le_group = cpu_to_le32(block_group);
1982
1983                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1984                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1985                 crc = crc16(crc, (__u8 *)gdp, offset);
1986                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1987                 /* for checksum of struct ext4_group_desc do the rest...*/
1988                 if ((sbi->s_es->s_feature_incompat &
1989                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1990                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1991                         crc = crc16(crc, (__u8 *)gdp + offset,
1992                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1993                                         offset);
1994         }
1995
1996         return cpu_to_le16(crc);
1997 }
1998
1999 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
2000                                 struct ext4_group_desc *gdp)
2001 {
2002         if ((sbi->s_es->s_feature_ro_compat &
2003              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
2004             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
2005                 return 0;
2006
2007         return 1;
2008 }
2009
2010 /* Called at mount-time, super-block is locked */
2011 static int ext4_check_descriptors(struct super_block *sb,
2012                                   ext4_group_t *first_not_zeroed)
2013 {
2014         struct ext4_sb_info *sbi = EXT4_SB(sb);
2015         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2016         ext4_fsblk_t last_block;
2017         ext4_fsblk_t block_bitmap;
2018         ext4_fsblk_t inode_bitmap;
2019         ext4_fsblk_t inode_table;
2020         int flexbg_flag = 0;
2021         ext4_group_t i, grp = sbi->s_groups_count;
2022
2023         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2024                 flexbg_flag = 1;
2025
2026         ext4_debug("Checking group descriptors");
2027
2028         for (i = 0; i < sbi->s_groups_count; i++) {
2029                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2030
2031                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2032                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2033                 else
2034                         last_block = first_block +
2035                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2036
2037                 if ((grp == sbi->s_groups_count) &&
2038                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2039                         grp = i;
2040
2041                 block_bitmap = ext4_block_bitmap(sb, gdp);
2042                 if (block_bitmap < first_block || block_bitmap > last_block) {
2043                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2044                                "Block bitmap for group %u not in group "
2045                                "(block %llu)!", i, block_bitmap);
2046                         return 0;
2047                 }
2048                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2049                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2050                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2051                                "Inode bitmap for group %u not in group "
2052                                "(block %llu)!", i, inode_bitmap);
2053                         return 0;
2054                 }
2055                 inode_table = ext4_inode_table(sb, gdp);
2056                 if (inode_table < first_block ||
2057                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2058                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2059                                "Inode table for group %u not in group "
2060                                "(block %llu)!", i, inode_table);
2061                         return 0;
2062                 }
2063                 ext4_lock_group(sb, i);
2064                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
2065                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2066                                  "Checksum for group %u failed (%u!=%u)",
2067                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2068                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2069                         if (!(sb->s_flags & MS_RDONLY)) {
2070                                 ext4_unlock_group(sb, i);
2071                                 return 0;
2072                         }
2073                 }
2074                 ext4_unlock_group(sb, i);
2075                 if (!flexbg_flag)
2076                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2077         }
2078         if (NULL != first_not_zeroed)
2079                 *first_not_zeroed = grp;
2080
2081         ext4_free_blocks_count_set(sbi->s_es, ext4_count_free_blocks(sb));
2082         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2083         return 1;
2084 }
2085
2086 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2087  * the superblock) which were deleted from all directories, but held open by
2088  * a process at the time of a crash.  We walk the list and try to delete these
2089  * inodes at recovery time (only with a read-write filesystem).
2090  *
2091  * In order to keep the orphan inode chain consistent during traversal (in
2092  * case of crash during recovery), we link each inode into the superblock
2093  * orphan list_head and handle it the same way as an inode deletion during
2094  * normal operation (which journals the operations for us).
2095  *
2096  * We only do an iget() and an iput() on each inode, which is very safe if we
2097  * accidentally point at an in-use or already deleted inode.  The worst that
2098  * can happen in this case is that we get a "bit already cleared" message from
2099  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2100  * e2fsck was run on this filesystem, and it must have already done the orphan
2101  * inode cleanup for us, so we can safely abort without any further action.
2102  */
2103 static void ext4_orphan_cleanup(struct super_block *sb,
2104                                 struct ext4_super_block *es)
2105 {
2106         unsigned int s_flags = sb->s_flags;
2107         int nr_orphans = 0, nr_truncates = 0;
2108 #ifdef CONFIG_QUOTA
2109         int i;
2110 #endif
2111         if (!es->s_last_orphan) {
2112                 jbd_debug(4, "no orphan inodes to clean up\n");
2113                 return;
2114         }
2115
2116         if (bdev_read_only(sb->s_bdev)) {
2117                 ext4_msg(sb, KERN_ERR, "write access "
2118                         "unavailable, skipping orphan cleanup");
2119                 return;
2120         }
2121
2122         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2123                 if (es->s_last_orphan)
2124                         jbd_debug(1, "Errors on filesystem, "
2125                                   "clearing orphan list.\n");
2126                 es->s_last_orphan = 0;
2127                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2128                 return;
2129         }
2130
2131         if (s_flags & MS_RDONLY) {
2132                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2133                 sb->s_flags &= ~MS_RDONLY;
2134         }
2135 #ifdef CONFIG_QUOTA
2136         /* Needed for iput() to work correctly and not trash data */
2137         sb->s_flags |= MS_ACTIVE;
2138         /* Turn on quotas so that they are updated correctly */
2139         for (i = 0; i < MAXQUOTAS; i++) {
2140                 if (EXT4_SB(sb)->s_qf_names[i]) {
2141                         int ret = ext4_quota_on_mount(sb, i);
2142                         if (ret < 0)
2143                                 ext4_msg(sb, KERN_ERR,
2144                                         "Cannot turn on journaled "
2145                                         "quota: error %d", ret);
2146                 }
2147         }
2148 #endif
2149
2150         while (es->s_last_orphan) {
2151                 struct inode *inode;
2152
2153                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2154                 if (IS_ERR(inode)) {
2155                         es->s_last_orphan = 0;
2156                         break;
2157                 }
2158
2159                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2160                 dquot_initialize(inode);
2161                 if (inode->i_nlink) {
2162                         ext4_msg(sb, KERN_DEBUG,
2163                                 "%s: truncating inode %lu to %lld bytes",
2164                                 __func__, inode->i_ino, inode->i_size);
2165                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2166                                   inode->i_ino, inode->i_size);
2167                         ext4_truncate(inode);
2168                         nr_truncates++;
2169                 } else {
2170                         ext4_msg(sb, KERN_DEBUG,
2171                                 "%s: deleting unreferenced inode %lu",
2172                                 __func__, inode->i_ino);
2173                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2174                                   inode->i_ino);
2175                         nr_orphans++;
2176                 }
2177                 iput(inode);  /* The delete magic happens here! */
2178         }
2179
2180 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2181
2182         if (nr_orphans)
2183                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2184                        PLURAL(nr_orphans));
2185         if (nr_truncates)
2186                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2187                        PLURAL(nr_truncates));
2188 #ifdef CONFIG_QUOTA
2189         /* Turn quotas off */
2190         for (i = 0; i < MAXQUOTAS; i++) {
2191                 if (sb_dqopt(sb)->files[i])
2192                         dquot_quota_off(sb, i);
2193         }
2194 #endif
2195         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2196 }
2197
2198 /*
2199  * Maximal extent format file size.
2200  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2201  * extent format containers, within a sector_t, and within i_blocks
2202  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2203  * so that won't be a limiting factor.
2204  *
2205  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2206  */
2207 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2208 {
2209         loff_t res;
2210         loff_t upper_limit = MAX_LFS_FILESIZE;
2211
2212         /* small i_blocks in vfs inode? */
2213         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2214                 /*
2215                  * CONFIG_LBDAF is not enabled implies the inode
2216                  * i_block represent total blocks in 512 bytes
2217                  * 32 == size of vfs inode i_blocks * 8
2218                  */
2219                 upper_limit = (1LL << 32) - 1;
2220
2221                 /* total blocks in file system block size */
2222                 upper_limit >>= (blkbits - 9);
2223                 upper_limit <<= blkbits;
2224         }
2225
2226         /* 32-bit extent-start container, ee_block */
2227         res = 1LL << 32;
2228         res <<= blkbits;
2229         res -= 1;
2230
2231         /* Sanity check against vm- & vfs- imposed limits */
2232         if (res > upper_limit)
2233                 res = upper_limit;
2234
2235         return res;
2236 }
2237
2238 /*
2239  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2240  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2241  * We need to be 1 filesystem block less than the 2^48 sector limit.
2242  */
2243 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2244 {
2245         loff_t res = EXT4_NDIR_BLOCKS;
2246         int meta_blocks;
2247         loff_t upper_limit;
2248         /* This is calculated to be the largest file size for a dense, block
2249          * mapped file such that the file's total number of 512-byte sectors,
2250          * including data and all indirect blocks, does not exceed (2^48 - 1).
2251          *
2252          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2253          * number of 512-byte sectors of the file.
2254          */
2255
2256         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2257                 /*
2258                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2259                  * the inode i_block field represents total file blocks in
2260                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2261                  */
2262                 upper_limit = (1LL << 32) - 1;
2263
2264                 /* total blocks in file system block size */
2265                 upper_limit >>= (bits - 9);
2266
2267         } else {
2268                 /*
2269                  * We use 48 bit ext4_inode i_blocks
2270                  * With EXT4_HUGE_FILE_FL set the i_blocks
2271                  * represent total number of blocks in
2272                  * file system block size
2273                  */
2274                 upper_limit = (1LL << 48) - 1;
2275
2276         }
2277
2278         /* indirect blocks */
2279         meta_blocks = 1;
2280         /* double indirect blocks */
2281         meta_blocks += 1 + (1LL << (bits-2));
2282         /* tripple indirect blocks */
2283         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2284
2285         upper_limit -= meta_blocks;
2286         upper_limit <<= bits;
2287
2288         res += 1LL << (bits-2);
2289         res += 1LL << (2*(bits-2));
2290         res += 1LL << (3*(bits-2));
2291         res <<= bits;
2292         if (res > upper_limit)
2293                 res = upper_limit;
2294
2295         if (res > MAX_LFS_FILESIZE)
2296                 res = MAX_LFS_FILESIZE;
2297
2298         return res;
2299 }
2300
2301 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2302                                    ext4_fsblk_t logical_sb_block, int nr)
2303 {
2304         struct ext4_sb_info *sbi = EXT4_SB(sb);
2305         ext4_group_t bg, first_meta_bg;
2306         int has_super = 0;
2307
2308         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2309
2310         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2311             nr < first_meta_bg)
2312                 return logical_sb_block + nr + 1;
2313         bg = sbi->s_desc_per_block * nr;
2314         if (ext4_bg_has_super(sb, bg))
2315                 has_super = 1;
2316
2317         return (has_super + ext4_group_first_block_no(sb, bg));
2318 }
2319
2320 /**
2321  * ext4_get_stripe_size: Get the stripe size.
2322  * @sbi: In memory super block info
2323  *
2324  * If we have specified it via mount option, then
2325  * use the mount option value. If the value specified at mount time is
2326  * greater than the blocks per group use the super block value.
2327  * If the super block value is greater than blocks per group return 0.
2328  * Allocator needs it be less than blocks per group.
2329  *
2330  */
2331 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2332 {
2333         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2334         unsigned long stripe_width =
2335                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2336
2337         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2338                 return sbi->s_stripe;
2339
2340         if (stripe_width <= sbi->s_blocks_per_group)
2341                 return stripe_width;
2342
2343         if (stride <= sbi->s_blocks_per_group)
2344                 return stride;
2345
2346         return 0;
2347 }
2348
2349 /* sysfs supprt */
2350
2351 struct ext4_attr {
2352         struct attribute attr;
2353         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2354         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2355                          const char *, size_t);
2356         int offset;
2357 };
2358
2359 static int parse_strtoul(const char *buf,
2360                 unsigned long max, unsigned long *value)
2361 {
2362         char *endp;
2363
2364         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2365         endp = skip_spaces(endp);
2366         if (*endp || *value > max)
2367                 return -EINVAL;
2368
2369         return 0;
2370 }
2371
2372 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2373                                               struct ext4_sb_info *sbi,
2374                                               char *buf)
2375 {
2376         return snprintf(buf, PAGE_SIZE, "%llu\n",
2377                         (s64) percpu_counter_sum(&sbi->s_dirtyblocks_counter));
2378 }
2379
2380 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2381                                          struct ext4_sb_info *sbi, char *buf)
2382 {
2383         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2384
2385         if (!sb->s_bdev->bd_part)
2386                 return snprintf(buf, PAGE_SIZE, "0\n");
2387         return snprintf(buf, PAGE_SIZE, "%lu\n",
2388                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2389                          sbi->s_sectors_written_start) >> 1);
2390 }
2391
2392 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2393                                           struct ext4_sb_info *sbi, char *buf)
2394 {
2395         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2396
2397         if (!sb->s_bdev->bd_part)
2398                 return snprintf(buf, PAGE_SIZE, "0\n");
2399         return snprintf(buf, PAGE_SIZE, "%llu\n",
2400                         (unsigned long long)(sbi->s_kbytes_written +
2401                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2402                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2403 }
2404
2405 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2406                                           struct ext4_sb_info *sbi,
2407                                           const char *buf, size_t count)
2408 {
2409         unsigned long t;
2410
2411         if (parse_strtoul(buf, 0x40000000, &t))
2412                 return -EINVAL;
2413
2414         if (!is_power_of_2(t))
2415                 return -EINVAL;
2416
2417         sbi->s_inode_readahead_blks = t;
2418         return count;
2419 }
2420
2421 static ssize_t sbi_ui_show(struct ext4_attr *a,
2422                            struct ext4_sb_info *sbi, char *buf)
2423 {
2424         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2425
2426         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2427 }
2428
2429 static ssize_t sbi_ui_store(struct ext4_attr *a,
2430                             struct ext4_sb_info *sbi,
2431                             const char *buf, size_t count)
2432 {
2433         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2434         unsigned long t;
2435
2436         if (parse_strtoul(buf, 0xffffffff, &t))
2437                 return -EINVAL;
2438         *ui = t;
2439         return count;
2440 }
2441
2442 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2443 static struct ext4_attr ext4_attr_##_name = {                   \
2444         .attr = {.name = __stringify(_name), .mode = _mode },   \
2445         .show   = _show,                                        \
2446         .store  = _store,                                       \
2447         .offset = offsetof(struct ext4_sb_info, _elname),       \
2448 }
2449 #define EXT4_ATTR(name, mode, show, store) \
2450 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2451
2452 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2453 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2454 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2455 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2456         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2457 #define ATTR_LIST(name) &ext4_attr_##name.attr
2458
2459 EXT4_RO_ATTR(delayed_allocation_blocks);
2460 EXT4_RO_ATTR(session_write_kbytes);
2461 EXT4_RO_ATTR(lifetime_write_kbytes);
2462 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2463                  inode_readahead_blks_store, s_inode_readahead_blks);
2464 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2465 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2466 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2467 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2468 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2469 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2470 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2471 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2472
2473 static struct attribute *ext4_attrs[] = {
2474         ATTR_LIST(delayed_allocation_blocks),
2475         ATTR_LIST(session_write_kbytes),
2476         ATTR_LIST(lifetime_write_kbytes),
2477         ATTR_LIST(inode_readahead_blks),
2478         ATTR_LIST(inode_goal),
2479         ATTR_LIST(mb_stats),
2480         ATTR_LIST(mb_max_to_scan),
2481         ATTR_LIST(mb_min_to_scan),
2482         ATTR_LIST(mb_order2_req),
2483         ATTR_LIST(mb_stream_req),
2484         ATTR_LIST(mb_group_prealloc),
2485         ATTR_LIST(max_writeback_mb_bump),
2486         NULL,
2487 };
2488
2489 /* Features this copy of ext4 supports */
2490 EXT4_INFO_ATTR(lazy_itable_init);
2491 EXT4_INFO_ATTR(batched_discard);
2492
2493 static struct attribute *ext4_feat_attrs[] = {
2494         ATTR_LIST(lazy_itable_init),
2495         ATTR_LIST(batched_discard),
2496         NULL,
2497 };
2498
2499 static ssize_t ext4_attr_show(struct kobject *kobj,
2500                               struct attribute *attr, char *buf)
2501 {
2502         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2503                                                 s_kobj);
2504         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2505
2506         return a->show ? a->show(a, sbi, buf) : 0;
2507 }
2508
2509 static ssize_t ext4_attr_store(struct kobject *kobj,
2510                                struct attribute *attr,
2511                                const char *buf, size_t len)
2512 {
2513         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2514                                                 s_kobj);
2515         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2516
2517         return a->store ? a->store(a, sbi, buf, len) : 0;
2518 }
2519
2520 static void ext4_sb_release(struct kobject *kobj)
2521 {
2522         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2523                                                 s_kobj);
2524         complete(&sbi->s_kobj_unregister);
2525 }
2526
2527 static const struct sysfs_ops ext4_attr_ops = {
2528         .show   = ext4_attr_show,
2529         .store  = ext4_attr_store,
2530 };
2531
2532 static struct kobj_type ext4_ktype = {
2533         .default_attrs  = ext4_attrs,
2534         .sysfs_ops      = &ext4_attr_ops,
2535         .release        = ext4_sb_release,
2536 };
2537
2538 static void ext4_feat_release(struct kobject *kobj)
2539 {
2540         complete(&ext4_feat->f_kobj_unregister);
2541 }
2542
2543 static struct kobj_type ext4_feat_ktype = {
2544         .default_attrs  = ext4_feat_attrs,
2545         .sysfs_ops      = &ext4_attr_ops,
2546         .release        = ext4_feat_release,
2547 };
2548
2549 /*
2550  * Check whether this filesystem can be mounted based on
2551  * the features present and the RDONLY/RDWR mount requested.
2552  * Returns 1 if this filesystem can be mounted as requested,
2553  * 0 if it cannot be.
2554  */
2555 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2556 {
2557         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2558                 ext4_msg(sb, KERN_ERR,
2559                         "Couldn't mount because of "
2560                         "unsupported optional features (%x)",
2561                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2562                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2563                 return 0;
2564         }
2565
2566         if (readonly)
2567                 return 1;
2568
2569         /* Check that feature set is OK for a read-write mount */
2570         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2571                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2572                          "unsupported optional features (%x)",
2573                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2574                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2575                 return 0;
2576         }
2577         /*
2578          * Large file size enabled file system can only be mounted
2579          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2580          */
2581         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2582                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2583                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2584                                  "cannot be mounted RDWR without "
2585                                  "CONFIG_LBDAF");
2586                         return 0;
2587                 }
2588         }
2589         return 1;
2590 }
2591
2592 /*
2593  * This function is called once a day if we have errors logged
2594  * on the file system
2595  */
2596 static void print_daily_error_info(unsigned long arg)
2597 {
2598         struct super_block *sb = (struct super_block *) arg;
2599         struct ext4_sb_info *sbi;
2600         struct ext4_super_block *es;
2601
2602         sbi = EXT4_SB(sb);
2603         es = sbi->s_es;
2604
2605         if (es->s_error_count)
2606                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2607                          le32_to_cpu(es->s_error_count));
2608         if (es->s_first_error_time) {
2609                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2610                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2611                        (int) sizeof(es->s_first_error_func),
2612                        es->s_first_error_func,
2613                        le32_to_cpu(es->s_first_error_line));
2614                 if (es->s_first_error_ino)
2615                         printk(": inode %u",
2616                                le32_to_cpu(es->s_first_error_ino));
2617                 if (es->s_first_error_block)
2618                         printk(": block %llu", (unsigned long long)
2619                                le64_to_cpu(es->s_first_error_block));
2620                 printk("\n");
2621         }
2622         if (es->s_last_error_time) {
2623                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2624                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2625                        (int) sizeof(es->s_last_error_func),
2626                        es->s_last_error_func,
2627                        le32_to_cpu(es->s_last_error_line));
2628                 if (es->s_last_error_ino)
2629                         printk(": inode %u",
2630                                le32_to_cpu(es->s_last_error_ino));
2631                 if (es->s_last_error_block)
2632                         printk(": block %llu", (unsigned long long)
2633                                le64_to_cpu(es->s_last_error_block));
2634                 printk("\n");
2635         }
2636         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2637 }
2638
2639 static void ext4_lazyinode_timeout(unsigned long data)
2640 {
2641         struct task_struct *p = (struct task_struct *)data;
2642         wake_up_process(p);
2643 }
2644
2645 /* Find next suitable group and run ext4_init_inode_table */
2646 static int ext4_run_li_request(struct ext4_li_request *elr)
2647 {
2648         struct ext4_group_desc *gdp = NULL;
2649         ext4_group_t group, ngroups;
2650         struct super_block *sb;
2651         unsigned long timeout = 0;
2652         int ret = 0;
2653
2654         sb = elr->lr_super;
2655         ngroups = EXT4_SB(sb)->s_groups_count;
2656
2657         for (group = elr->lr_next_group; group < ngroups; group++) {
2658                 gdp = ext4_get_group_desc(sb, group, NULL);
2659                 if (!gdp) {
2660                         ret = 1;
2661                         break;
2662                 }
2663
2664                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2665                         break;
2666         }
2667
2668         if (group == ngroups)
2669                 ret = 1;
2670
2671         if (!ret) {
2672                 timeout = jiffies;
2673                 ret = ext4_init_inode_table(sb, group,
2674                                             elr->lr_timeout ? 0 : 1);
2675                 if (elr->lr_timeout == 0) {
2676                         timeout = jiffies - timeout;
2677                         if (elr->lr_sbi->s_li_wait_mult)
2678                                 timeout *= elr->lr_sbi->s_li_wait_mult;
2679                         else
2680                                 timeout *= 20;
2681                         elr->lr_timeout = timeout;
2682                 }
2683                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2684                 elr->lr_next_group = group + 1;
2685         }
2686
2687         return ret;
2688 }
2689
2690 /*
2691  * Remove lr_request from the list_request and free the
2692  * request tructure. Should be called with li_list_mtx held
2693  */
2694 static void ext4_remove_li_request(struct ext4_li_request *elr)
2695 {
2696         struct ext4_sb_info *sbi;
2697
2698         if (!elr)
2699                 return;
2700
2701         sbi = elr->lr_sbi;
2702
2703         list_del(&elr->lr_request);
2704         sbi->s_li_request = NULL;
2705         kfree(elr);
2706 }
2707
2708 static void ext4_unregister_li_request(struct super_block *sb)
2709 {
2710         struct ext4_li_request *elr = EXT4_SB(sb)->s_li_request;
2711
2712         if (!ext4_li_info)
2713                 return;
2714
2715         mutex_lock(&ext4_li_info->li_list_mtx);
2716         ext4_remove_li_request(elr);
2717         mutex_unlock(&ext4_li_info->li_list_mtx);
2718 }
2719
2720 /*
2721  * This is the function where ext4lazyinit thread lives. It walks
2722  * through the request list searching for next scheduled filesystem.
2723  * When such a fs is found, run the lazy initialization request
2724  * (ext4_rn_li_request) and keep track of the time spend in this
2725  * function. Based on that time we compute next schedule time of
2726  * the request. When walking through the list is complete, compute
2727  * next waking time and put itself into sleep.
2728  */
2729 static int ext4_lazyinit_thread(void *arg)
2730 {
2731         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2732         struct list_head *pos, *n;
2733         struct ext4_li_request *elr;
2734         unsigned long next_wakeup;
2735         DEFINE_WAIT(wait);
2736
2737         BUG_ON(NULL == eli);
2738
2739         eli->li_timer.data = (unsigned long)current;
2740         eli->li_timer.function = ext4_lazyinode_timeout;
2741
2742         eli->li_task = current;
2743         wake_up(&eli->li_wait_task);
2744
2745 cont_thread:
2746         while (true) {
2747                 next_wakeup = MAX_JIFFY_OFFSET;
2748
2749                 mutex_lock(&eli->li_list_mtx);
2750                 if (list_empty(&eli->li_request_list)) {
2751                         mutex_unlock(&eli->li_list_mtx);
2752                         goto exit_thread;
2753                 }
2754
2755                 list_for_each_safe(pos, n, &eli->li_request_list) {
2756                         elr = list_entry(pos, struct ext4_li_request,
2757                                          lr_request);
2758
2759                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2760                                 if (ext4_run_li_request(elr) != 0) {
2761                                         /* error, remove the lazy_init job */
2762                                         ext4_remove_li_request(elr);
2763                                         continue;
2764                                 }
2765                         }
2766
2767                         if (time_before(elr->lr_next_sched, next_wakeup))
2768                                 next_wakeup = elr->lr_next_sched;
2769                 }
2770                 mutex_unlock(&eli->li_list_mtx);
2771
2772                 if (freezing(current))
2773                         refrigerator();
2774
2775                 if ((time_after_eq(jiffies, next_wakeup)) ||
2776                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2777                         cond_resched();
2778                         continue;
2779                 }
2780
2781                 eli->li_timer.expires = next_wakeup;
2782                 add_timer(&eli->li_timer);
2783                 prepare_to_wait(&eli->li_wait_daemon, &wait,
2784                                 TASK_INTERRUPTIBLE);
2785                 if (time_before(jiffies, next_wakeup))
2786                         schedule();
2787                 finish_wait(&eli->li_wait_daemon, &wait);
2788         }
2789
2790 exit_thread:
2791         /*
2792          * It looks like the request list is empty, but we need
2793          * to check it under the li_list_mtx lock, to prevent any
2794          * additions into it, and of course we should lock ext4_li_mtx
2795          * to atomically free the list and ext4_li_info, because at
2796          * this point another ext4 filesystem could be registering
2797          * new one.
2798          */
2799         mutex_lock(&ext4_li_mtx);
2800         mutex_lock(&eli->li_list_mtx);
2801         if (!list_empty(&eli->li_request_list)) {
2802                 mutex_unlock(&eli->li_list_mtx);
2803                 mutex_unlock(&ext4_li_mtx);
2804                 goto cont_thread;
2805         }
2806         mutex_unlock(&eli->li_list_mtx);
2807         del_timer_sync(&ext4_li_info->li_timer);
2808         eli->li_task = NULL;
2809         wake_up(&eli->li_wait_task);
2810
2811         kfree(ext4_li_info);
2812         ext4_li_info = NULL;
2813         mutex_unlock(&ext4_li_mtx);
2814
2815         return 0;
2816 }
2817
2818 static void ext4_clear_request_list(void)
2819 {
2820         struct list_head *pos, *n;
2821         struct ext4_li_request *elr;
2822
2823         mutex_lock(&ext4_li_info->li_list_mtx);
2824         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2825                 elr = list_entry(pos, struct ext4_li_request,
2826                                  lr_request);
2827                 ext4_remove_li_request(elr);
2828         }
2829         mutex_unlock(&ext4_li_info->li_list_mtx);
2830 }
2831
2832 static int ext4_run_lazyinit_thread(void)
2833 {
2834         struct task_struct *t;
2835
2836         t = kthread_run(ext4_lazyinit_thread, ext4_li_info, "ext4lazyinit");
2837         if (IS_ERR(t)) {
2838                 int err = PTR_ERR(t);
2839                 ext4_clear_request_list();
2840                 del_timer_sync(&ext4_li_info->li_timer);
2841                 kfree(ext4_li_info);
2842                 ext4_li_info = NULL;
2843                 printk(KERN_CRIT "EXT4: error %d creating inode table "
2844                                  "initialization thread\n",
2845                                  err);
2846                 return err;
2847         }
2848         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2849
2850         wait_event(ext4_li_info->li_wait_task, ext4_li_info->li_task != NULL);
2851         return 0;
2852 }
2853
2854 /*
2855  * Check whether it make sense to run itable init. thread or not.
2856  * If there is at least one uninitialized inode table, return
2857  * corresponding group number, else the loop goes through all
2858  * groups and return total number of groups.
2859  */
2860 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2861 {
2862         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2863         struct ext4_group_desc *gdp = NULL;
2864
2865         for (group = 0; group < ngroups; group++) {
2866                 gdp = ext4_get_group_desc(sb, group, NULL);
2867                 if (!gdp)
2868                         continue;
2869
2870                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2871                         break;
2872         }
2873
2874         return group;
2875 }
2876
2877 static int ext4_li_info_new(void)
2878 {
2879         struct ext4_lazy_init *eli = NULL;
2880
2881         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2882         if (!eli)
2883                 return -ENOMEM;
2884
2885         eli->li_task = NULL;
2886         INIT_LIST_HEAD(&eli->li_request_list);
2887         mutex_init(&eli->li_list_mtx);
2888
2889         init_waitqueue_head(&eli->li_wait_daemon);
2890         init_waitqueue_head(&eli->li_wait_task);
2891         init_timer(&eli->li_timer);
2892         eli->li_state |= EXT4_LAZYINIT_QUIT;
2893
2894         ext4_li_info = eli;
2895
2896         return 0;
2897 }
2898
2899 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2900                                             ext4_group_t start)
2901 {
2902         struct ext4_sb_info *sbi = EXT4_SB(sb);
2903         struct ext4_li_request *elr;
2904         unsigned long rnd;
2905
2906         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2907         if (!elr)
2908                 return NULL;
2909
2910         elr->lr_super = sb;
2911         elr->lr_sbi = sbi;
2912         elr->lr_next_group = start;
2913
2914         /*
2915          * Randomize first schedule time of the request to
2916          * spread the inode table initialization requests
2917          * better.
2918          */
2919         get_random_bytes(&rnd, sizeof(rnd));
2920         elr->lr_next_sched = jiffies + (unsigned long)rnd %
2921                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
2922
2923         return elr;
2924 }
2925
2926 static int ext4_register_li_request(struct super_block *sb,
2927                                     ext4_group_t first_not_zeroed)
2928 {
2929         struct ext4_sb_info *sbi = EXT4_SB(sb);
2930         struct ext4_li_request *elr;
2931         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2932         int ret = 0;
2933
2934         if (sbi->s_li_request != NULL)
2935                 return 0;
2936
2937         if (first_not_zeroed == ngroups ||
2938             (sb->s_flags & MS_RDONLY) ||
2939             !test_opt(sb, INIT_INODE_TABLE)) {
2940                 sbi->s_li_request = NULL;
2941                 return 0;
2942         }
2943
2944         if (first_not_zeroed == ngroups) {
2945                 sbi->s_li_request = NULL;
2946                 return 0;
2947         }
2948
2949         elr = ext4_li_request_new(sb, first_not_zeroed);
2950         if (!elr)
2951                 return -ENOMEM;
2952
2953         mutex_lock(&ext4_li_mtx);
2954
2955         if (NULL == ext4_li_info) {
2956                 ret = ext4_li_info_new();
2957                 if (ret)
2958                         goto out;
2959         }
2960
2961         mutex_lock(&ext4_li_info->li_list_mtx);
2962         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
2963         mutex_unlock(&ext4_li_info->li_list_mtx);
2964
2965         sbi->s_li_request = elr;
2966
2967         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
2968                 ret = ext4_run_lazyinit_thread();
2969                 if (ret)
2970                         goto out;
2971         }
2972 out:
2973         mutex_unlock(&ext4_li_mtx);
2974         if (ret)
2975                 kfree(elr);
2976         return ret;
2977 }
2978
2979 /*
2980  * We do not need to lock anything since this is called on
2981  * module unload.
2982  */
2983 static void ext4_destroy_lazyinit_thread(void)
2984 {
2985         /*
2986          * If thread exited earlier
2987          * there's nothing to be done.
2988          */
2989         if (!ext4_li_info)
2990                 return;
2991
2992         ext4_clear_request_list();
2993
2994         while (ext4_li_info->li_task) {
2995                 wake_up(&ext4_li_info->li_wait_daemon);
2996                 wait_event(ext4_li_info->li_wait_task,
2997                            ext4_li_info->li_task == NULL);
2998         }
2999 }
3000
3001 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3002                                 __releases(kernel_lock)
3003                                 __acquires(kernel_lock)
3004 {
3005         char *orig_data = kstrdup(data, GFP_KERNEL);
3006         struct buffer_head *bh;
3007         struct ext4_super_block *es = NULL;
3008         struct ext4_sb_info *sbi;
3009         ext4_fsblk_t block;
3010         ext4_fsblk_t sb_block = get_sb_block(&data);
3011         ext4_fsblk_t logical_sb_block;
3012         unsigned long offset = 0;
3013         unsigned long journal_devnum = 0;
3014         unsigned long def_mount_opts;
3015         struct inode *root;
3016         char *cp;
3017         const char *descr;
3018         int ret = -ENOMEM;
3019         int blocksize;
3020         unsigned int db_count;
3021         unsigned int i;
3022         int needs_recovery, has_huge_files;
3023         __u64 blocks_count;
3024         int err;
3025         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3026         ext4_group_t first_not_zeroed;
3027
3028         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3029         if (!sbi)
3030                 goto out_free_orig;
3031
3032         sbi->s_blockgroup_lock =
3033                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3034         if (!sbi->s_blockgroup_lock) {
3035                 kfree(sbi);
3036                 goto out_free_orig;
3037         }
3038         sb->s_fs_info = sbi;
3039         sbi->s_mount_opt = 0;
3040         sbi->s_resuid = EXT4_DEF_RESUID;
3041         sbi->s_resgid = EXT4_DEF_RESGID;
3042         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3043         sbi->s_sb_block = sb_block;
3044         if (sb->s_bdev->bd_part)
3045                 sbi->s_sectors_written_start =
3046                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3047
3048         /* Cleanup superblock name */
3049         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3050                 *cp = '!';
3051
3052         ret = -EINVAL;
3053         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3054         if (!blocksize) {
3055                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3056                 goto out_fail;
3057         }
3058
3059         /*
3060          * The ext4 superblock will not be buffer aligned for other than 1kB
3061          * block sizes.  We need to calculate the offset from buffer start.
3062          */
3063         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3064                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3065                 offset = do_div(logical_sb_block, blocksize);
3066         } else {
3067                 logical_sb_block = sb_block;
3068         }
3069
3070         if (!(bh = sb_bread(sb, logical_sb_block))) {
3071                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3072                 goto out_fail;
3073         }
3074         /*
3075          * Note: s_es must be initialized as soon as possible because
3076          *       some ext4 macro-instructions depend on its value
3077          */
3078         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3079         sbi->s_es = es;
3080         sb->s_magic = le16_to_cpu(es->s_magic);
3081         if (sb->s_magic != EXT4_SUPER_MAGIC)
3082                 goto cantfind_ext4;
3083         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3084
3085         /* Set defaults before we parse the mount options */
3086         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3087         set_opt(sb, INIT_INODE_TABLE);
3088         if (def_mount_opts & EXT4_DEFM_DEBUG)
3089                 set_opt(sb, DEBUG);
3090         if (def_mount_opts & EXT4_DEFM_BSDGROUPS) {
3091                 ext4_msg(sb, KERN_WARNING, deprecated_msg, "bsdgroups",
3092                         "2.6.38");
3093                 set_opt(sb, GRPID);
3094         }
3095         if (def_mount_opts & EXT4_DEFM_UID16)
3096                 set_opt(sb, NO_UID32);
3097 #ifdef CONFIG_EXT4_FS_XATTR
3098         if (def_mount_opts & EXT4_DEFM_XATTR_USER)
3099                 set_opt(sb, XATTR_USER);
3100 #endif
3101 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3102         if (def_mount_opts & EXT4_DEFM_ACL)
3103                 set_opt(sb, POSIX_ACL);
3104 #endif
3105         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3106                 set_opt(sb, JOURNAL_DATA);
3107         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3108                 set_opt(sb, ORDERED_DATA);
3109         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3110                 set_opt(sb, WRITEBACK_DATA);
3111
3112         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3113                 set_opt(sb, ERRORS_PANIC);
3114         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3115                 set_opt(sb, ERRORS_CONT);
3116         else
3117                 set_opt(sb, ERRORS_RO);
3118         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3119                 set_opt(sb, BLOCK_VALIDITY);
3120         if (def_mount_opts & EXT4_DEFM_DISCARD)
3121                 set_opt(sb, DISCARD);
3122
3123         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
3124         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
3125         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3126         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3127         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3128
3129         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3130                 set_opt(sb, BARRIER);
3131
3132         /*
3133          * enable delayed allocation by default
3134          * Use -o nodelalloc to turn it off
3135          */
3136         if (!IS_EXT3_SB(sb) &&
3137             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3138                 set_opt(sb, DELALLOC);
3139
3140         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3141                            &journal_devnum, &journal_ioprio, NULL, 0)) {
3142                 ext4_msg(sb, KERN_WARNING,
3143                          "failed to parse options in superblock: %s",
3144                          sbi->s_es->s_mount_opts);
3145         }
3146         if (!parse_options((char *) data, sb, &journal_devnum,
3147                            &journal_ioprio, NULL, 0))
3148                 goto failed_mount;
3149
3150         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3151                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3152
3153         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3154             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3155              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3156              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3157                 ext4_msg(sb, KERN_WARNING,
3158                        "feature flags set on rev 0 fs, "
3159                        "running e2fsck is recommended");
3160
3161         /*
3162          * Check feature flags regardless of the revision level, since we
3163          * previously didn't change the revision level when setting the flags,
3164          * so there is a chance incompat flags are set on a rev 0 filesystem.
3165          */
3166         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3167                 goto failed_mount;
3168
3169         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3170
3171         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3172             blocksize > EXT4_MAX_BLOCK_SIZE) {
3173                 ext4_msg(sb, KERN_ERR,
3174                        "Unsupported filesystem blocksize %d", blocksize);
3175                 goto failed_mount;
3176         }