ext4: Report max_batch_time option correctly
[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 <linux/cleancache.h>
42 #include <asm/uaccess.h>
43
44 #include <linux/kthread.h>
45 #include <linux/freezer.h>
46
47 #include "ext4.h"
48 #include "ext4_extents.h"
49 #include "ext4_jbd2.h"
50 #include "xattr.h"
51 #include "acl.h"
52 #include "mballoc.h"
53
54 #define CREATE_TRACE_POINTS
55 #include <trace/events/ext4.h>
56
57 static struct proc_dir_entry *ext4_proc_root;
58 static struct kset *ext4_kset;
59 static struct ext4_lazy_init *ext4_li_info;
60 static struct mutex ext4_li_mtx;
61 static struct ext4_features *ext4_feat;
62
63 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
64                              unsigned long journal_devnum);
65 static int ext4_commit_super(struct super_block *sb, int sync);
66 static void ext4_mark_recovery_complete(struct super_block *sb,
67                                         struct ext4_super_block *es);
68 static void ext4_clear_journal_err(struct super_block *sb,
69                                    struct ext4_super_block *es);
70 static int ext4_sync_fs(struct super_block *sb, int wait);
71 static const char *ext4_decode_error(struct super_block *sb, int errno,
72                                      char nbuf[16]);
73 static int ext4_remount(struct super_block *sb, int *flags, char *data);
74 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
75 static int ext4_unfreeze(struct super_block *sb);
76 static void ext4_write_super(struct super_block *sb);
77 static int ext4_freeze(struct super_block *sb);
78 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
79                        const char *dev_name, void *data);
80 static inline int ext2_feature_set_ok(struct super_block *sb);
81 static inline int ext3_feature_set_ok(struct super_block *sb);
82 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
83 static void ext4_destroy_lazyinit_thread(void);
84 static void ext4_unregister_li_request(struct super_block *sb);
85 static void ext4_clear_request_list(void);
86
87 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
88 static struct file_system_type ext2_fs_type = {
89         .owner          = THIS_MODULE,
90         .name           = "ext2",
91         .mount          = ext4_mount,
92         .kill_sb        = kill_block_super,
93         .fs_flags       = FS_REQUIRES_DEV,
94 };
95 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
96 #else
97 #define IS_EXT2_SB(sb) (0)
98 #endif
99
100
101 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
102 static struct file_system_type ext3_fs_type = {
103         .owner          = THIS_MODULE,
104         .name           = "ext3",
105         .mount          = ext4_mount,
106         .kill_sb        = kill_block_super,
107         .fs_flags       = FS_REQUIRES_DEV,
108 };
109 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
110 #else
111 #define IS_EXT3_SB(sb) (0)
112 #endif
113
114 void *ext4_kvmalloc(size_t size, gfp_t flags)
115 {
116         void *ret;
117
118         ret = kmalloc(size, flags);
119         if (!ret)
120                 ret = __vmalloc(size, flags, PAGE_KERNEL);
121         return ret;
122 }
123
124 void *ext4_kvzalloc(size_t size, gfp_t flags)
125 {
126         void *ret;
127
128         ret = kzalloc(size, flags);
129         if (!ret)
130                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
131         return ret;
132 }
133
134 void ext4_kvfree(void *ptr)
135 {
136         if (is_vmalloc_addr(ptr))
137                 vfree(ptr);
138         else
139                 kfree(ptr);
140
141 }
142
143 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
144                                struct ext4_group_desc *bg)
145 {
146         return le32_to_cpu(bg->bg_block_bitmap_lo) |
147                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
148                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
149 }
150
151 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
152                                struct ext4_group_desc *bg)
153 {
154         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
155                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
156                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
157 }
158
159 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
160                               struct ext4_group_desc *bg)
161 {
162         return le32_to_cpu(bg->bg_inode_table_lo) |
163                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
164                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
165 }
166
167 __u32 ext4_free_group_clusters(struct super_block *sb,
168                                struct ext4_group_desc *bg)
169 {
170         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
171                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
172                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
173 }
174
175 __u32 ext4_free_inodes_count(struct super_block *sb,
176                               struct ext4_group_desc *bg)
177 {
178         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
179                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
180                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
181 }
182
183 __u32 ext4_used_dirs_count(struct super_block *sb,
184                               struct ext4_group_desc *bg)
185 {
186         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
187                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
188                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
189 }
190
191 __u32 ext4_itable_unused_count(struct super_block *sb,
192                               struct ext4_group_desc *bg)
193 {
194         return le16_to_cpu(bg->bg_itable_unused_lo) |
195                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
196                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
197 }
198
199 void ext4_block_bitmap_set(struct super_block *sb,
200                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
201 {
202         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
203         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
204                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
205 }
206
207 void ext4_inode_bitmap_set(struct super_block *sb,
208                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
209 {
210         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
211         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
212                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
213 }
214
215 void ext4_inode_table_set(struct super_block *sb,
216                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
217 {
218         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
219         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
220                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
221 }
222
223 void ext4_free_group_clusters_set(struct super_block *sb,
224                                   struct ext4_group_desc *bg, __u32 count)
225 {
226         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
227         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
228                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
229 }
230
231 void ext4_free_inodes_set(struct super_block *sb,
232                           struct ext4_group_desc *bg, __u32 count)
233 {
234         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
235         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
236                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
237 }
238
239 void ext4_used_dirs_set(struct super_block *sb,
240                           struct ext4_group_desc *bg, __u32 count)
241 {
242         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
243         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
244                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
245 }
246
247 void ext4_itable_unused_set(struct super_block *sb,
248                           struct ext4_group_desc *bg, __u32 count)
249 {
250         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
251         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
252                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
253 }
254
255
256 /* Just increment the non-pointer handle value */
257 static handle_t *ext4_get_nojournal(void)
258 {
259         handle_t *handle = current->journal_info;
260         unsigned long ref_cnt = (unsigned long)handle;
261
262         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
263
264         ref_cnt++;
265         handle = (handle_t *)ref_cnt;
266
267         current->journal_info = handle;
268         return handle;
269 }
270
271
272 /* Decrement the non-pointer handle value */
273 static void ext4_put_nojournal(handle_t *handle)
274 {
275         unsigned long ref_cnt = (unsigned long)handle;
276
277         BUG_ON(ref_cnt == 0);
278
279         ref_cnt--;
280         handle = (handle_t *)ref_cnt;
281
282         current->journal_info = handle;
283 }
284
285 /*
286  * Wrappers for jbd2_journal_start/end.
287  *
288  * The only special thing we need to do here is to make sure that all
289  * journal_end calls result in the superblock being marked dirty, so
290  * that sync() will call the filesystem's write_super callback if
291  * appropriate.
292  *
293  * To avoid j_barrier hold in userspace when a user calls freeze(),
294  * ext4 prevents a new handle from being started by s_frozen, which
295  * is in an upper layer.
296  */
297 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
298 {
299         journal_t *journal;
300         handle_t  *handle;
301
302         trace_ext4_journal_start(sb, nblocks, _RET_IP_);
303         if (sb->s_flags & MS_RDONLY)
304                 return ERR_PTR(-EROFS);
305
306         journal = EXT4_SB(sb)->s_journal;
307         handle = ext4_journal_current_handle();
308
309         /*
310          * If a handle has been started, it should be allowed to
311          * finish, otherwise deadlock could happen between freeze
312          * and others(e.g. truncate) due to the restart of the
313          * journal handle if the filesystem is forzen and active
314          * handles are not stopped.
315          */
316         if (!handle)
317                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
318
319         if (!journal)
320                 return ext4_get_nojournal();
321         /*
322          * Special case here: if the journal has aborted behind our
323          * backs (eg. EIO in the commit thread), then we still need to
324          * take the FS itself readonly cleanly.
325          */
326         if (is_journal_aborted(journal)) {
327                 ext4_abort(sb, "Detected aborted journal");
328                 return ERR_PTR(-EROFS);
329         }
330         return jbd2_journal_start(journal, nblocks);
331 }
332
333 /*
334  * The only special thing we need to do here is to make sure that all
335  * jbd2_journal_stop calls result in the superblock being marked dirty, so
336  * that sync() will call the filesystem's write_super callback if
337  * appropriate.
338  */
339 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
340 {
341         struct super_block *sb;
342         int err;
343         int rc;
344
345         if (!ext4_handle_valid(handle)) {
346                 ext4_put_nojournal(handle);
347                 return 0;
348         }
349         sb = handle->h_transaction->t_journal->j_private;
350         err = handle->h_err;
351         rc = jbd2_journal_stop(handle);
352
353         if (!err)
354                 err = rc;
355         if (err)
356                 __ext4_std_error(sb, where, line, err);
357         return err;
358 }
359
360 void ext4_journal_abort_handle(const char *caller, unsigned int line,
361                                const char *err_fn, struct buffer_head *bh,
362                                handle_t *handle, int err)
363 {
364         char nbuf[16];
365         const char *errstr = ext4_decode_error(NULL, err, nbuf);
366
367         BUG_ON(!ext4_handle_valid(handle));
368
369         if (bh)
370                 BUFFER_TRACE(bh, "abort");
371
372         if (!handle->h_err)
373                 handle->h_err = err;
374
375         if (is_handle_aborted(handle))
376                 return;
377
378         printk(KERN_ERR "%s:%d: aborting transaction: %s in %s\n",
379                caller, line, errstr, err_fn);
380
381         jbd2_journal_abort_handle(handle);
382 }
383
384 static void __save_error_info(struct super_block *sb, const char *func,
385                             unsigned int line)
386 {
387         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
388
389         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
390         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
391         es->s_last_error_time = cpu_to_le32(get_seconds());
392         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
393         es->s_last_error_line = cpu_to_le32(line);
394         if (!es->s_first_error_time) {
395                 es->s_first_error_time = es->s_last_error_time;
396                 strncpy(es->s_first_error_func, func,
397                         sizeof(es->s_first_error_func));
398                 es->s_first_error_line = cpu_to_le32(line);
399                 es->s_first_error_ino = es->s_last_error_ino;
400                 es->s_first_error_block = es->s_last_error_block;
401         }
402         /*
403          * Start the daily error reporting function if it hasn't been
404          * started already
405          */
406         if (!es->s_error_count)
407                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
408         es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
409 }
410
411 static void save_error_info(struct super_block *sb, const char *func,
412                             unsigned int line)
413 {
414         __save_error_info(sb, func, line);
415         ext4_commit_super(sb, 1);
416 }
417
418 /*
419  * The del_gendisk() function uninitializes the disk-specific data
420  * structures, including the bdi structure, without telling anyone
421  * else.  Once this happens, any attempt to call mark_buffer_dirty()
422  * (for example, by ext4_commit_super), will cause a kernel OOPS.
423  * This is a kludge to prevent these oops until we can put in a proper
424  * hook in del_gendisk() to inform the VFS and file system layers.
425  */
426 static int block_device_ejected(struct super_block *sb)
427 {
428         struct inode *bd_inode = sb->s_bdev->bd_inode;
429         struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
430
431         return bdi->dev == NULL;
432 }
433
434
435 /* Deal with the reporting of failure conditions on a filesystem such as
436  * inconsistencies detected or read IO failures.
437  *
438  * On ext2, we can store the error state of the filesystem in the
439  * superblock.  That is not possible on ext4, because we may have other
440  * write ordering constraints on the superblock which prevent us from
441  * writing it out straight away; and given that the journal is about to
442  * be aborted, we can't rely on the current, or future, transactions to
443  * write out the superblock safely.
444  *
445  * We'll just use the jbd2_journal_abort() error code to record an error in
446  * the journal instead.  On recovery, the journal will complain about
447  * that error until we've noted it down and cleared it.
448  */
449
450 static void ext4_handle_error(struct super_block *sb)
451 {
452         if (sb->s_flags & MS_RDONLY)
453                 return;
454
455         if (!test_opt(sb, ERRORS_CONT)) {
456                 journal_t *journal = EXT4_SB(sb)->s_journal;
457
458                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
459                 if (journal)
460                         jbd2_journal_abort(journal, -EIO);
461         }
462         if (test_opt(sb, ERRORS_RO)) {
463                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
464                 sb->s_flags |= MS_RDONLY;
465         }
466         if (test_opt(sb, ERRORS_PANIC))
467                 panic("EXT4-fs (device %s): panic forced after error\n",
468                         sb->s_id);
469 }
470
471 void __ext4_error(struct super_block *sb, const char *function,
472                   unsigned int line, const char *fmt, ...)
473 {
474         struct va_format vaf;
475         va_list args;
476
477         va_start(args, fmt);
478         vaf.fmt = fmt;
479         vaf.va = &args;
480         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
481                sb->s_id, function, line, current->comm, &vaf);
482         va_end(args);
483         save_error_info(sb, function, line);
484
485         ext4_handle_error(sb);
486 }
487
488 void ext4_error_inode(struct inode *inode, const char *function,
489                       unsigned int line, ext4_fsblk_t block,
490                       const char *fmt, ...)
491 {
492         va_list args;
493         struct va_format vaf;
494         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
495
496         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
497         es->s_last_error_block = cpu_to_le64(block);
498         save_error_info(inode->i_sb, function, line);
499         va_start(args, fmt);
500         vaf.fmt = fmt;
501         vaf.va = &args;
502         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
503                inode->i_sb->s_id, function, line, inode->i_ino);
504         if (block)
505                 printk(KERN_CONT "block %llu: ", block);
506         printk(KERN_CONT "comm %s: %pV\n", current->comm, &vaf);
507         va_end(args);
508
509         ext4_handle_error(inode->i_sb);
510 }
511
512 void ext4_error_file(struct file *file, const char *function,
513                      unsigned int line, ext4_fsblk_t block,
514                      const char *fmt, ...)
515 {
516         va_list args;
517         struct va_format vaf;
518         struct ext4_super_block *es;
519         struct inode *inode = file->f_dentry->d_inode;
520         char pathname[80], *path;
521
522         es = EXT4_SB(inode->i_sb)->s_es;
523         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
524         save_error_info(inode->i_sb, function, line);
525         path = d_path(&(file->f_path), pathname, sizeof(pathname));
526         if (IS_ERR(path))
527                 path = "(unknown)";
528         printk(KERN_CRIT
529                "EXT4-fs error (device %s): %s:%d: inode #%lu: ",
530                inode->i_sb->s_id, function, line, inode->i_ino);
531         if (block)
532                 printk(KERN_CONT "block %llu: ", block);
533         va_start(args, fmt);
534         vaf.fmt = fmt;
535         vaf.va = &args;
536         printk(KERN_CONT "comm %s: path %s: %pV\n", current->comm, path, &vaf);
537         va_end(args);
538
539         ext4_handle_error(inode->i_sb);
540 }
541
542 static const char *ext4_decode_error(struct super_block *sb, int errno,
543                                      char nbuf[16])
544 {
545         char *errstr = NULL;
546
547         switch (errno) {
548         case -EIO:
549                 errstr = "IO failure";
550                 break;
551         case -ENOMEM:
552                 errstr = "Out of memory";
553                 break;
554         case -EROFS:
555                 if (!sb || (EXT4_SB(sb)->s_journal &&
556                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
557                         errstr = "Journal has aborted";
558                 else
559                         errstr = "Readonly filesystem";
560                 break;
561         default:
562                 /* If the caller passed in an extra buffer for unknown
563                  * errors, textualise them now.  Else we just return
564                  * NULL. */
565                 if (nbuf) {
566                         /* Check for truncated error codes... */
567                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
568                                 errstr = nbuf;
569                 }
570                 break;
571         }
572
573         return errstr;
574 }
575
576 /* __ext4_std_error decodes expected errors from journaling functions
577  * automatically and invokes the appropriate error response.  */
578
579 void __ext4_std_error(struct super_block *sb, const char *function,
580                       unsigned int line, int errno)
581 {
582         char nbuf[16];
583         const char *errstr;
584
585         /* Special case: if the error is EROFS, and we're not already
586          * inside a transaction, then there's really no point in logging
587          * an error. */
588         if (errno == -EROFS && journal_current_handle() == NULL &&
589             (sb->s_flags & MS_RDONLY))
590                 return;
591
592         errstr = ext4_decode_error(sb, errno, nbuf);
593         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
594                sb->s_id, function, line, errstr);
595         save_error_info(sb, function, line);
596
597         ext4_handle_error(sb);
598 }
599
600 /*
601  * ext4_abort is a much stronger failure handler than ext4_error.  The
602  * abort function may be used to deal with unrecoverable failures such
603  * as journal IO errors or ENOMEM at a critical moment in log management.
604  *
605  * We unconditionally force the filesystem into an ABORT|READONLY state,
606  * unless the error response on the fs has been set to panic in which
607  * case we take the easy way out and panic immediately.
608  */
609
610 void __ext4_abort(struct super_block *sb, const char *function,
611                 unsigned int line, const char *fmt, ...)
612 {
613         va_list args;
614
615         save_error_info(sb, function, line);
616         va_start(args, fmt);
617         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
618                function, line);
619         vprintk(fmt, args);
620         printk("\n");
621         va_end(args);
622
623         if ((sb->s_flags & MS_RDONLY) == 0) {
624                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
625                 sb->s_flags |= MS_RDONLY;
626                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
627                 if (EXT4_SB(sb)->s_journal)
628                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
629                 save_error_info(sb, function, line);
630         }
631         if (test_opt(sb, ERRORS_PANIC))
632                 panic("EXT4-fs panic from previous error\n");
633 }
634
635 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
636 {
637         struct va_format vaf;
638         va_list args;
639
640         va_start(args, fmt);
641         vaf.fmt = fmt;
642         vaf.va = &args;
643         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
644         va_end(args);
645 }
646
647 void __ext4_warning(struct super_block *sb, const char *function,
648                     unsigned int line, const char *fmt, ...)
649 {
650         struct va_format vaf;
651         va_list args;
652
653         va_start(args, fmt);
654         vaf.fmt = fmt;
655         vaf.va = &args;
656         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
657                sb->s_id, function, line, &vaf);
658         va_end(args);
659 }
660
661 void __ext4_grp_locked_error(const char *function, unsigned int line,
662                              struct super_block *sb, ext4_group_t grp,
663                              unsigned long ino, ext4_fsblk_t block,
664                              const char *fmt, ...)
665 __releases(bitlock)
666 __acquires(bitlock)
667 {
668         struct va_format vaf;
669         va_list args;
670         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
671
672         es->s_last_error_ino = cpu_to_le32(ino);
673         es->s_last_error_block = cpu_to_le64(block);
674         __save_error_info(sb, function, line);
675
676         va_start(args, fmt);
677
678         vaf.fmt = fmt;
679         vaf.va = &args;
680         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
681                sb->s_id, function, line, grp);
682         if (ino)
683                 printk(KERN_CONT "inode %lu: ", ino);
684         if (block)
685                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
686         printk(KERN_CONT "%pV\n", &vaf);
687         va_end(args);
688
689         if (test_opt(sb, ERRORS_CONT)) {
690                 ext4_commit_super(sb, 0);
691                 return;
692         }
693
694         ext4_unlock_group(sb, grp);
695         ext4_handle_error(sb);
696         /*
697          * We only get here in the ERRORS_RO case; relocking the group
698          * may be dangerous, but nothing bad will happen since the
699          * filesystem will have already been marked read/only and the
700          * journal has been aborted.  We return 1 as a hint to callers
701          * who might what to use the return value from
702          * ext4_grp_locked_error() to distinguish between the
703          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
704          * aggressively from the ext4 function in question, with a
705          * more appropriate error code.
706          */
707         ext4_lock_group(sb, grp);
708         return;
709 }
710
711 void ext4_update_dynamic_rev(struct super_block *sb)
712 {
713         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
714
715         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
716                 return;
717
718         ext4_warning(sb,
719                      "updating to rev %d because of new feature flag, "
720                      "running e2fsck is recommended",
721                      EXT4_DYNAMIC_REV);
722
723         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
724         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
725         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
726         /* leave es->s_feature_*compat flags alone */
727         /* es->s_uuid will be set by e2fsck if empty */
728
729         /*
730          * The rest of the superblock fields should be zero, and if not it
731          * means they are likely already in use, so leave them alone.  We
732          * can leave it up to e2fsck to clean up any inconsistencies there.
733          */
734 }
735
736 /*
737  * Open the external journal device
738  */
739 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
740 {
741         struct block_device *bdev;
742         char b[BDEVNAME_SIZE];
743
744         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
745         if (IS_ERR(bdev))
746                 goto fail;
747         return bdev;
748
749 fail:
750         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
751                         __bdevname(dev, b), PTR_ERR(bdev));
752         return NULL;
753 }
754
755 /*
756  * Release the journal device
757  */
758 static int ext4_blkdev_put(struct block_device *bdev)
759 {
760         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
761 }
762
763 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
764 {
765         struct block_device *bdev;
766         int ret = -ENODEV;
767
768         bdev = sbi->journal_bdev;
769         if (bdev) {
770                 ret = ext4_blkdev_put(bdev);
771                 sbi->journal_bdev = NULL;
772         }
773         return ret;
774 }
775
776 static inline struct inode *orphan_list_entry(struct list_head *l)
777 {
778         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
779 }
780
781 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
782 {
783         struct list_head *l;
784
785         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
786                  le32_to_cpu(sbi->s_es->s_last_orphan));
787
788         printk(KERN_ERR "sb_info orphan list:\n");
789         list_for_each(l, &sbi->s_orphan) {
790                 struct inode *inode = orphan_list_entry(l);
791                 printk(KERN_ERR "  "
792                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
793                        inode->i_sb->s_id, inode->i_ino, inode,
794                        inode->i_mode, inode->i_nlink,
795                        NEXT_ORPHAN(inode));
796         }
797 }
798
799 static void ext4_put_super(struct super_block *sb)
800 {
801         struct ext4_sb_info *sbi = EXT4_SB(sb);
802         struct ext4_super_block *es = sbi->s_es;
803         int i, err;
804
805         ext4_unregister_li_request(sb);
806         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
807
808         flush_workqueue(sbi->dio_unwritten_wq);
809         destroy_workqueue(sbi->dio_unwritten_wq);
810
811         lock_super(sb);
812         if (sb->s_dirt)
813                 ext4_commit_super(sb, 1);
814
815         if (sbi->s_journal) {
816                 err = jbd2_journal_destroy(sbi->s_journal);
817                 sbi->s_journal = NULL;
818                 if (err < 0)
819                         ext4_abort(sb, "Couldn't clean up the journal");
820         }
821
822         del_timer(&sbi->s_err_report);
823         ext4_release_system_zone(sb);
824         ext4_mb_release(sb);
825         ext4_ext_release(sb);
826         ext4_xattr_put_super(sb);
827
828         if (!(sb->s_flags & MS_RDONLY)) {
829                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
830                 es->s_state = cpu_to_le16(sbi->s_mount_state);
831                 ext4_commit_super(sb, 1);
832         }
833         if (sbi->s_proc) {
834                 remove_proc_entry(sb->s_id, ext4_proc_root);
835         }
836         kobject_del(&sbi->s_kobj);
837
838         for (i = 0; i < sbi->s_gdb_count; i++)
839                 brelse(sbi->s_group_desc[i]);
840         ext4_kvfree(sbi->s_group_desc);
841         ext4_kvfree(sbi->s_flex_groups);
842         percpu_counter_destroy(&sbi->s_freeclusters_counter);
843         percpu_counter_destroy(&sbi->s_freeinodes_counter);
844         percpu_counter_destroy(&sbi->s_dirs_counter);
845         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
846         brelse(sbi->s_sbh);
847 #ifdef CONFIG_QUOTA
848         for (i = 0; i < MAXQUOTAS; i++)
849                 kfree(sbi->s_qf_names[i]);
850 #endif
851
852         /* Debugging code just in case the in-memory inode orphan list
853          * isn't empty.  The on-disk one can be non-empty if we've
854          * detected an error and taken the fs readonly, but the
855          * in-memory list had better be clean by this point. */
856         if (!list_empty(&sbi->s_orphan))
857                 dump_orphan_list(sb, sbi);
858         J_ASSERT(list_empty(&sbi->s_orphan));
859
860         invalidate_bdev(sb->s_bdev);
861         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
862                 /*
863                  * Invalidate the journal device's buffers.  We don't want them
864                  * floating about in memory - the physical journal device may
865                  * hotswapped, and it breaks the `ro-after' testing code.
866                  */
867                 sync_blockdev(sbi->journal_bdev);
868                 invalidate_bdev(sbi->journal_bdev);
869                 ext4_blkdev_remove(sbi);
870         }
871         if (sbi->s_mmp_tsk)
872                 kthread_stop(sbi->s_mmp_tsk);
873         sb->s_fs_info = NULL;
874         /*
875          * Now that we are completely done shutting down the
876          * superblock, we need to actually destroy the kobject.
877          */
878         unlock_super(sb);
879         kobject_put(&sbi->s_kobj);
880         wait_for_completion(&sbi->s_kobj_unregister);
881         kfree(sbi->s_blockgroup_lock);
882         kfree(sbi);
883 }
884
885 static struct kmem_cache *ext4_inode_cachep;
886
887 /*
888  * Called inside transaction, so use GFP_NOFS
889  */
890 static struct inode *ext4_alloc_inode(struct super_block *sb)
891 {
892         struct ext4_inode_info *ei;
893
894         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
895         if (!ei)
896                 return NULL;
897
898         ei->vfs_inode.i_version = 1;
899         ei->vfs_inode.i_data.writeback_index = 0;
900         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
901         INIT_LIST_HEAD(&ei->i_prealloc_list);
902         spin_lock_init(&ei->i_prealloc_lock);
903         ei->i_reserved_data_blocks = 0;
904         ei->i_reserved_meta_blocks = 0;
905         ei->i_allocated_meta_blocks = 0;
906         ei->i_da_metadata_calc_len = 0;
907         spin_lock_init(&(ei->i_block_reservation_lock));
908 #ifdef CONFIG_QUOTA
909         ei->i_reserved_quota = 0;
910 #endif
911         ei->jinode = NULL;
912         INIT_LIST_HEAD(&ei->i_completed_io_list);
913         spin_lock_init(&ei->i_completed_io_lock);
914         ei->cur_aio_dio = NULL;
915         ei->i_sync_tid = 0;
916         ei->i_datasync_tid = 0;
917         atomic_set(&ei->i_ioend_count, 0);
918         atomic_set(&ei->i_aiodio_unwritten, 0);
919
920         return &ei->vfs_inode;
921 }
922
923 static int ext4_drop_inode(struct inode *inode)
924 {
925         int drop = generic_drop_inode(inode);
926
927         trace_ext4_drop_inode(inode, drop);
928         return drop;
929 }
930
931 static void ext4_i_callback(struct rcu_head *head)
932 {
933         struct inode *inode = container_of(head, struct inode, i_rcu);
934         INIT_LIST_HEAD(&inode->i_dentry);
935         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
936 }
937
938 static void ext4_destroy_inode(struct inode *inode)
939 {
940         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
941                 ext4_msg(inode->i_sb, KERN_ERR,
942                          "Inode %lu (%p): orphan list check failed!",
943                          inode->i_ino, EXT4_I(inode));
944                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
945                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
946                                 true);
947                 dump_stack();
948         }
949         call_rcu(&inode->i_rcu, ext4_i_callback);
950 }
951
952 static void init_once(void *foo)
953 {
954         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
955
956         INIT_LIST_HEAD(&ei->i_orphan);
957 #ifdef CONFIG_EXT4_FS_XATTR
958         init_rwsem(&ei->xattr_sem);
959 #endif
960         init_rwsem(&ei->i_data_sem);
961         inode_init_once(&ei->vfs_inode);
962 }
963
964 static int init_inodecache(void)
965 {
966         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
967                                              sizeof(struct ext4_inode_info),
968                                              0, (SLAB_RECLAIM_ACCOUNT|
969                                                 SLAB_MEM_SPREAD),
970                                              init_once);
971         if (ext4_inode_cachep == NULL)
972                 return -ENOMEM;
973         return 0;
974 }
975
976 static void destroy_inodecache(void)
977 {
978         kmem_cache_destroy(ext4_inode_cachep);
979 }
980
981 void ext4_clear_inode(struct inode *inode)
982 {
983         invalidate_inode_buffers(inode);
984         end_writeback(inode);
985         dquot_drop(inode);
986         ext4_discard_preallocations(inode);
987         if (EXT4_I(inode)->jinode) {
988                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
989                                                EXT4_I(inode)->jinode);
990                 jbd2_free_inode(EXT4_I(inode)->jinode);
991                 EXT4_I(inode)->jinode = NULL;
992         }
993 }
994
995 static inline void ext4_show_quota_options(struct seq_file *seq,
996                                            struct super_block *sb)
997 {
998 #if defined(CONFIG_QUOTA)
999         struct ext4_sb_info *sbi = EXT4_SB(sb);
1000
1001         if (sbi->s_jquota_fmt) {
1002                 char *fmtname = "";
1003
1004                 switch (sbi->s_jquota_fmt) {
1005                 case QFMT_VFS_OLD:
1006                         fmtname = "vfsold";
1007                         break;
1008                 case QFMT_VFS_V0:
1009                         fmtname = "vfsv0";
1010                         break;
1011                 case QFMT_VFS_V1:
1012                         fmtname = "vfsv1";
1013                         break;
1014                 }
1015                 seq_printf(seq, ",jqfmt=%s", fmtname);
1016         }
1017
1018         if (sbi->s_qf_names[USRQUOTA])
1019                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1020
1021         if (sbi->s_qf_names[GRPQUOTA])
1022                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1023
1024         if (test_opt(sb, USRQUOTA))
1025                 seq_puts(seq, ",usrquota");
1026
1027         if (test_opt(sb, GRPQUOTA))
1028                 seq_puts(seq, ",grpquota");
1029 #endif
1030 }
1031
1032 /*
1033  * Show an option if
1034  *  - it's set to a non-default value OR
1035  *  - if the per-sb default is different from the global default
1036  */
1037 static int ext4_show_options(struct seq_file *seq, struct vfsmount *vfs)
1038 {
1039         int def_errors;
1040         unsigned long def_mount_opts;
1041         struct super_block *sb = vfs->mnt_sb;
1042         struct ext4_sb_info *sbi = EXT4_SB(sb);
1043         struct ext4_super_block *es = sbi->s_es;
1044
1045         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
1046         def_errors     = le16_to_cpu(es->s_errors);
1047
1048         if (sbi->s_sb_block != 1)
1049                 seq_printf(seq, ",sb=%llu", sbi->s_sb_block);
1050         if (test_opt(sb, MINIX_DF))
1051                 seq_puts(seq, ",minixdf");
1052         if (test_opt(sb, GRPID) && !(def_mount_opts & EXT4_DEFM_BSDGROUPS))
1053                 seq_puts(seq, ",grpid");
1054         if (!test_opt(sb, GRPID) && (def_mount_opts & EXT4_DEFM_BSDGROUPS))
1055                 seq_puts(seq, ",nogrpid");
1056         if (sbi->s_resuid != EXT4_DEF_RESUID ||
1057             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID) {
1058                 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
1059         }
1060         if (sbi->s_resgid != EXT4_DEF_RESGID ||
1061             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) {
1062                 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
1063         }
1064         if (test_opt(sb, ERRORS_RO)) {
1065                 if (def_errors == EXT4_ERRORS_PANIC ||
1066                     def_errors == EXT4_ERRORS_CONTINUE) {
1067                         seq_puts(seq, ",errors=remount-ro");
1068                 }
1069         }
1070         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1071                 seq_puts(seq, ",errors=continue");
1072         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1073                 seq_puts(seq, ",errors=panic");
1074         if (test_opt(sb, NO_UID32) && !(def_mount_opts & EXT4_DEFM_UID16))
1075                 seq_puts(seq, ",nouid32");
1076         if (test_opt(sb, DEBUG) && !(def_mount_opts & EXT4_DEFM_DEBUG))
1077                 seq_puts(seq, ",debug");
1078 #ifdef CONFIG_EXT4_FS_XATTR
1079         if (test_opt(sb, XATTR_USER))
1080                 seq_puts(seq, ",user_xattr");
1081         if (!test_opt(sb, XATTR_USER))
1082                 seq_puts(seq, ",nouser_xattr");
1083 #endif
1084 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1085         if (test_opt(sb, POSIX_ACL) && !(def_mount_opts & EXT4_DEFM_ACL))
1086                 seq_puts(seq, ",acl");
1087         if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT4_DEFM_ACL))
1088                 seq_puts(seq, ",noacl");
1089 #endif
1090         if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
1091                 seq_printf(seq, ",commit=%u",
1092                            (unsigned) (sbi->s_commit_interval / HZ));
1093         }
1094         if (sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME) {
1095                 seq_printf(seq, ",min_batch_time=%u",
1096                            (unsigned) sbi->s_min_batch_time);
1097         }
1098         if (sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME) {
1099                 seq_printf(seq, ",max_batch_time=%u",
1100                            (unsigned) sbi->s_max_batch_time);
1101         }
1102
1103         /*
1104          * We're changing the default of barrier mount option, so
1105          * let's always display its mount state so it's clear what its
1106          * status is.
1107          */
1108         seq_puts(seq, ",barrier=");
1109         seq_puts(seq, test_opt(sb, BARRIER) ? "1" : "0");
1110         if (test_opt(sb, JOURNAL_ASYNC_COMMIT))
1111                 seq_puts(seq, ",journal_async_commit");
1112         else if (test_opt(sb, JOURNAL_CHECKSUM))
1113                 seq_puts(seq, ",journal_checksum");
1114         if (test_opt(sb, I_VERSION))
1115                 seq_puts(seq, ",i_version");
1116         if (!test_opt(sb, DELALLOC) &&
1117             !(def_mount_opts & EXT4_DEFM_NODELALLOC))
1118                 seq_puts(seq, ",nodelalloc");
1119
1120         if (!test_opt(sb, MBLK_IO_SUBMIT))
1121                 seq_puts(seq, ",nomblk_io_submit");
1122         if (sbi->s_stripe)
1123                 seq_printf(seq, ",stripe=%lu", sbi->s_stripe);
1124         /*
1125          * journal mode get enabled in different ways
1126          * So just print the value even if we didn't specify it
1127          */
1128         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1129                 seq_puts(seq, ",data=journal");
1130         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1131                 seq_puts(seq, ",data=ordered");
1132         else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1133                 seq_puts(seq, ",data=writeback");
1134
1135         if (sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1136                 seq_printf(seq, ",inode_readahead_blks=%u",
1137                            sbi->s_inode_readahead_blks);
1138
1139         if (test_opt(sb, DATA_ERR_ABORT))
1140                 seq_puts(seq, ",data_err=abort");
1141
1142         if (test_opt(sb, NO_AUTO_DA_ALLOC))
1143                 seq_puts(seq, ",noauto_da_alloc");
1144
1145         if (test_opt(sb, DISCARD) && !(def_mount_opts & EXT4_DEFM_DISCARD))
1146                 seq_puts(seq, ",discard");
1147
1148         if (test_opt(sb, NOLOAD))
1149                 seq_puts(seq, ",norecovery");
1150
1151         if (test_opt(sb, DIOREAD_NOLOCK))
1152                 seq_puts(seq, ",dioread_nolock");
1153
1154         if (test_opt(sb, BLOCK_VALIDITY) &&
1155             !(def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY))
1156                 seq_puts(seq, ",block_validity");
1157
1158         if (!test_opt(sb, INIT_INODE_TABLE))
1159                 seq_puts(seq, ",noinit_itable");
1160         else if (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)
1161                 seq_printf(seq, ",init_itable=%u",
1162                            (unsigned) sbi->s_li_wait_mult);
1163
1164         ext4_show_quota_options(seq, sb);
1165
1166         return 0;
1167 }
1168
1169 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1170                                         u64 ino, u32 generation)
1171 {
1172         struct inode *inode;
1173
1174         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1175                 return ERR_PTR(-ESTALE);
1176         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1177                 return ERR_PTR(-ESTALE);
1178
1179         /* iget isn't really right if the inode is currently unallocated!!
1180          *
1181          * ext4_read_inode will return a bad_inode if the inode had been
1182          * deleted, so we should be safe.
1183          *
1184          * Currently we don't know the generation for parent directory, so
1185          * a generation of 0 means "accept any"
1186          */
1187         inode = ext4_iget(sb, ino);
1188         if (IS_ERR(inode))
1189                 return ERR_CAST(inode);
1190         if (generation && inode->i_generation != generation) {
1191                 iput(inode);
1192                 return ERR_PTR(-ESTALE);
1193         }
1194
1195         return inode;
1196 }
1197
1198 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1199                                         int fh_len, int fh_type)
1200 {
1201         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1202                                     ext4_nfs_get_inode);
1203 }
1204
1205 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1206                                         int fh_len, int fh_type)
1207 {
1208         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1209                                     ext4_nfs_get_inode);
1210 }
1211
1212 /*
1213  * Try to release metadata pages (indirect blocks, directories) which are
1214  * mapped via the block device.  Since these pages could have journal heads
1215  * which would prevent try_to_free_buffers() from freeing them, we must use
1216  * jbd2 layer's try_to_free_buffers() function to release them.
1217  */
1218 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1219                                  gfp_t wait)
1220 {
1221         journal_t *journal = EXT4_SB(sb)->s_journal;
1222
1223         WARN_ON(PageChecked(page));
1224         if (!page_has_buffers(page))
1225                 return 0;
1226         if (journal)
1227                 return jbd2_journal_try_to_free_buffers(journal, page,
1228                                                         wait & ~__GFP_WAIT);
1229         return try_to_free_buffers(page);
1230 }
1231
1232 #ifdef CONFIG_QUOTA
1233 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1234 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1235
1236 static int ext4_write_dquot(struct dquot *dquot);
1237 static int ext4_acquire_dquot(struct dquot *dquot);
1238 static int ext4_release_dquot(struct dquot *dquot);
1239 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1240 static int ext4_write_info(struct super_block *sb, int type);
1241 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1242                          struct path *path);
1243 static int ext4_quota_off(struct super_block *sb, int type);
1244 static int ext4_quota_on_mount(struct super_block *sb, int type);
1245 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1246                                size_t len, loff_t off);
1247 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1248                                 const char *data, size_t len, loff_t off);
1249
1250 static const struct dquot_operations ext4_quota_operations = {
1251         .get_reserved_space = ext4_get_reserved_space,
1252         .write_dquot    = ext4_write_dquot,
1253         .acquire_dquot  = ext4_acquire_dquot,
1254         .release_dquot  = ext4_release_dquot,
1255         .mark_dirty     = ext4_mark_dquot_dirty,
1256         .write_info     = ext4_write_info,
1257         .alloc_dquot    = dquot_alloc,
1258         .destroy_dquot  = dquot_destroy,
1259 };
1260
1261 static const struct quotactl_ops ext4_qctl_operations = {
1262         .quota_on       = ext4_quota_on,
1263         .quota_off      = ext4_quota_off,
1264         .quota_sync     = dquot_quota_sync,
1265         .get_info       = dquot_get_dqinfo,
1266         .set_info       = dquot_set_dqinfo,
1267         .get_dqblk      = dquot_get_dqblk,
1268         .set_dqblk      = dquot_set_dqblk
1269 };
1270 #endif
1271
1272 static const struct super_operations ext4_sops = {
1273         .alloc_inode    = ext4_alloc_inode,
1274         .destroy_inode  = ext4_destroy_inode,
1275         .write_inode    = ext4_write_inode,
1276         .dirty_inode    = ext4_dirty_inode,
1277         .drop_inode     = ext4_drop_inode,
1278         .evict_inode    = ext4_evict_inode,
1279         .put_super      = ext4_put_super,
1280         .sync_fs        = ext4_sync_fs,
1281         .freeze_fs      = ext4_freeze,
1282         .unfreeze_fs    = ext4_unfreeze,
1283         .statfs         = ext4_statfs,
1284         .remount_fs     = ext4_remount,
1285         .show_options   = ext4_show_options,
1286 #ifdef CONFIG_QUOTA
1287         .quota_read     = ext4_quota_read,
1288         .quota_write    = ext4_quota_write,
1289 #endif
1290         .bdev_try_to_free_page = bdev_try_to_free_page,
1291 };
1292
1293 static const struct super_operations ext4_nojournal_sops = {
1294         .alloc_inode    = ext4_alloc_inode,
1295         .destroy_inode  = ext4_destroy_inode,
1296         .write_inode    = ext4_write_inode,
1297         .dirty_inode    = ext4_dirty_inode,
1298         .drop_inode     = ext4_drop_inode,
1299         .evict_inode    = ext4_evict_inode,
1300         .write_super    = ext4_write_super,
1301         .put_super      = ext4_put_super,
1302         .statfs         = ext4_statfs,
1303         .remount_fs     = ext4_remount,
1304         .show_options   = ext4_show_options,
1305 #ifdef CONFIG_QUOTA
1306         .quota_read     = ext4_quota_read,
1307         .quota_write    = ext4_quota_write,
1308 #endif
1309         .bdev_try_to_free_page = bdev_try_to_free_page,
1310 };
1311
1312 static const struct export_operations ext4_export_ops = {
1313         .fh_to_dentry = ext4_fh_to_dentry,
1314         .fh_to_parent = ext4_fh_to_parent,
1315         .get_parent = ext4_get_parent,
1316 };
1317
1318 enum {
1319         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1320         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1321         Opt_nouid32, Opt_debug, Opt_oldalloc, Opt_orlov,
1322         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1323         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload, Opt_nobh, Opt_bh,
1324         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1325         Opt_journal_update, Opt_journal_dev,
1326         Opt_journal_checksum, Opt_journal_async_commit,
1327         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1328         Opt_data_err_abort, Opt_data_err_ignore,
1329         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1330         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1331         Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
1332         Opt_resize, Opt_usrquota, Opt_grpquota, Opt_i_version,
1333         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1334         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1335         Opt_inode_readahead_blks, Opt_journal_ioprio,
1336         Opt_dioread_nolock, Opt_dioread_lock,
1337         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1338 };
1339
1340 static const match_table_t tokens = {
1341         {Opt_bsd_df, "bsddf"},
1342         {Opt_minix_df, "minixdf"},
1343         {Opt_grpid, "grpid"},
1344         {Opt_grpid, "bsdgroups"},
1345         {Opt_nogrpid, "nogrpid"},
1346         {Opt_nogrpid, "sysvgroups"},
1347         {Opt_resgid, "resgid=%u"},
1348         {Opt_resuid, "resuid=%u"},
1349         {Opt_sb, "sb=%u"},
1350         {Opt_err_cont, "errors=continue"},
1351         {Opt_err_panic, "errors=panic"},
1352         {Opt_err_ro, "errors=remount-ro"},
1353         {Opt_nouid32, "nouid32"},
1354         {Opt_debug, "debug"},
1355         {Opt_oldalloc, "oldalloc"},
1356         {Opt_orlov, "orlov"},
1357         {Opt_user_xattr, "user_xattr"},
1358         {Opt_nouser_xattr, "nouser_xattr"},
1359         {Opt_acl, "acl"},
1360         {Opt_noacl, "noacl"},
1361         {Opt_noload, "noload"},
1362         {Opt_noload, "norecovery"},
1363         {Opt_nobh, "nobh"},
1364         {Opt_bh, "bh"},
1365         {Opt_commit, "commit=%u"},
1366         {Opt_min_batch_time, "min_batch_time=%u"},
1367         {Opt_max_batch_time, "max_batch_time=%u"},
1368         {Opt_journal_update, "journal=update"},
1369         {Opt_journal_dev, "journal_dev=%u"},
1370         {Opt_journal_checksum, "journal_checksum"},
1371         {Opt_journal_async_commit, "journal_async_commit"},
1372         {Opt_abort, "abort"},
1373         {Opt_data_journal, "data=journal"},
1374         {Opt_data_ordered, "data=ordered"},
1375         {Opt_data_writeback, "data=writeback"},
1376         {Opt_data_err_abort, "data_err=abort"},
1377         {Opt_data_err_ignore, "data_err=ignore"},
1378         {Opt_offusrjquota, "usrjquota="},
1379         {Opt_usrjquota, "usrjquota=%s"},
1380         {Opt_offgrpjquota, "grpjquota="},
1381         {Opt_grpjquota, "grpjquota=%s"},
1382         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1383         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1384         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1385         {Opt_grpquota, "grpquota"},
1386         {Opt_noquota, "noquota"},
1387         {Opt_quota, "quota"},
1388         {Opt_usrquota, "usrquota"},
1389         {Opt_barrier, "barrier=%u"},
1390         {Opt_barrier, "barrier"},
1391         {Opt_nobarrier, "nobarrier"},
1392         {Opt_i_version, "i_version"},
1393         {Opt_stripe, "stripe=%u"},
1394         {Opt_resize, "resize"},
1395         {Opt_delalloc, "delalloc"},
1396         {Opt_nodelalloc, "nodelalloc"},
1397         {Opt_mblk_io_submit, "mblk_io_submit"},
1398         {Opt_nomblk_io_submit, "nomblk_io_submit"},
1399         {Opt_block_validity, "block_validity"},
1400         {Opt_noblock_validity, "noblock_validity"},
1401         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1402         {Opt_journal_ioprio, "journal_ioprio=%u"},
1403         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1404         {Opt_auto_da_alloc, "auto_da_alloc"},
1405         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1406         {Opt_dioread_nolock, "dioread_nolock"},
1407         {Opt_dioread_lock, "dioread_lock"},
1408         {Opt_discard, "discard"},
1409         {Opt_nodiscard, "nodiscard"},
1410         {Opt_init_itable, "init_itable=%u"},
1411         {Opt_init_itable, "init_itable"},
1412         {Opt_noinit_itable, "noinit_itable"},
1413         {Opt_err, NULL},
1414 };
1415
1416 static ext4_fsblk_t get_sb_block(void **data)
1417 {
1418         ext4_fsblk_t    sb_block;
1419         char            *options = (char *) *data;
1420
1421         if (!options || strncmp(options, "sb=", 3) != 0)
1422                 return 1;       /* Default location */
1423
1424         options += 3;
1425         /* TODO: use simple_strtoll with >32bit ext4 */
1426         sb_block = simple_strtoul(options, &options, 0);
1427         if (*options && *options != ',') {
1428                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1429                        (char *) *data);
1430                 return 1;
1431         }
1432         if (*options == ',')
1433                 options++;
1434         *data = (void *) options;
1435
1436         return sb_block;
1437 }
1438
1439 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1440 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1441         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1442
1443 #ifdef CONFIG_QUOTA
1444 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1445 {
1446         struct ext4_sb_info *sbi = EXT4_SB(sb);
1447         char *qname;
1448
1449         if (sb_any_quota_loaded(sb) &&
1450                 !sbi->s_qf_names[qtype]) {
1451                 ext4_msg(sb, KERN_ERR,
1452                         "Cannot change journaled "
1453                         "quota options when quota turned on");
1454                 return 0;
1455         }
1456         qname = match_strdup(args);
1457         if (!qname) {
1458                 ext4_msg(sb, KERN_ERR,
1459                         "Not enough memory for storing quotafile name");
1460                 return 0;
1461         }
1462         if (sbi->s_qf_names[qtype] &&
1463                 strcmp(sbi->s_qf_names[qtype], qname)) {
1464                 ext4_msg(sb, KERN_ERR,
1465                         "%s quota file already specified", QTYPE2NAME(qtype));
1466                 kfree(qname);
1467                 return 0;
1468         }
1469         sbi->s_qf_names[qtype] = qname;
1470         if (strchr(sbi->s_qf_names[qtype], '/')) {
1471                 ext4_msg(sb, KERN_ERR,
1472                         "quotafile must be on filesystem root");
1473                 kfree(sbi->s_qf_names[qtype]);
1474                 sbi->s_qf_names[qtype] = NULL;
1475                 return 0;
1476         }
1477         set_opt(sb, QUOTA);
1478         return 1;
1479 }
1480
1481 static int clear_qf_name(struct super_block *sb, int qtype)
1482 {
1483
1484         struct ext4_sb_info *sbi = EXT4_SB(sb);
1485
1486         if (sb_any_quota_loaded(sb) &&
1487                 sbi->s_qf_names[qtype]) {
1488                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1489                         " when quota turned on");
1490                 return 0;
1491         }
1492         /*
1493          * The space will be released later when all options are confirmed
1494          * to be correct
1495          */
1496         sbi->s_qf_names[qtype] = NULL;
1497         return 1;
1498 }
1499 #endif
1500
1501 static int parse_options(char *options, struct super_block *sb,
1502                          unsigned long *journal_devnum,
1503                          unsigned int *journal_ioprio,
1504                          ext4_fsblk_t *n_blocks_count, int is_remount)
1505 {
1506         struct ext4_sb_info *sbi = EXT4_SB(sb);
1507         char *p;
1508         substring_t args[MAX_OPT_ARGS];
1509         int data_opt = 0;
1510         int option;
1511 #ifdef CONFIG_QUOTA
1512         int qfmt;
1513 #endif
1514
1515         if (!options)
1516                 return 1;
1517
1518         while ((p = strsep(&options, ",")) != NULL) {
1519                 int token;
1520                 if (!*p)
1521                         continue;
1522
1523                 /*
1524                  * Initialize args struct so we know whether arg was
1525                  * found; some options take optional arguments.
1526                  */
1527                 args[0].to = args[0].from = NULL;
1528                 token = match_token(p, tokens, args);
1529                 switch (token) {
1530                 case Opt_bsd_df:
1531                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1532                         clear_opt(sb, MINIX_DF);
1533                         break;
1534                 case Opt_minix_df:
1535                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1536                         set_opt(sb, MINIX_DF);
1537
1538                         break;
1539                 case Opt_grpid:
1540                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1541                         set_opt(sb, GRPID);
1542
1543                         break;
1544                 case Opt_nogrpid:
1545                         ext4_msg(sb, KERN_WARNING, deprecated_msg, p, "2.6.38");
1546                         clear_opt(sb, GRPID);
1547
1548                         break;
1549                 case Opt_resuid:
1550                         if (match_int(&args[0], &option))
1551                                 return 0;
1552                         sbi->s_resuid = option;
1553                         break;
1554                 case Opt_resgid:
1555                         if (match_int(&args[0], &option))
1556                                 return 0;
1557                         sbi->s_resgid = option;
1558                         break;
1559                 case Opt_sb:
1560                         /* handled by get_sb_block() instead of here */
1561                         /* *sb_block = match_int(&args[0]); */
1562                         break;
1563                 case Opt_err_panic:
1564                         clear_opt(sb, ERRORS_CONT);
1565                         clear_opt(sb, ERRORS_RO);
1566                         set_opt(sb, ERRORS_PANIC);
1567                         break;
1568                 case Opt_err_ro:
1569                         clear_opt(sb, ERRORS_CONT);
1570                         clear_opt(sb, ERRORS_PANIC);
1571                         set_opt(sb, ERRORS_RO);
1572                         break;
1573                 case Opt_err_cont:
1574                         clear_opt(sb, ERRORS_RO);
1575                         clear_opt(sb, ERRORS_PANIC);
1576                         set_opt(sb, ERRORS_CONT);
1577                         break;
1578                 case Opt_nouid32:
1579                         set_opt(sb, NO_UID32);
1580                         break;
1581                 case Opt_debug:
1582                         set_opt(sb, DEBUG);
1583                         break;
1584                 case Opt_oldalloc:
1585                         ext4_msg(sb, KERN_WARNING,
1586                                  "Ignoring deprecated oldalloc option");
1587                         break;
1588                 case Opt_orlov:
1589                         ext4_msg(sb, KERN_WARNING,
1590                                  "Ignoring deprecated orlov option");
1591                         break;
1592 #ifdef CONFIG_EXT4_FS_XATTR
1593                 case Opt_user_xattr:
1594                         set_opt(sb, XATTR_USER);
1595                         break;
1596                 case Opt_nouser_xattr:
1597                         clear_opt(sb, XATTR_USER);
1598                         break;
1599 #else
1600                 case Opt_user_xattr:
1601                 case Opt_nouser_xattr:
1602                         ext4_msg(sb, KERN_ERR, "(no)user_xattr options not supported");
1603                         break;
1604 #endif
1605 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1606                 case Opt_acl:
1607                         set_opt(sb, POSIX_ACL);
1608                         break;
1609                 case Opt_noacl:
1610                         clear_opt(sb, POSIX_ACL);
1611                         break;
1612 #else
1613                 case Opt_acl:
1614                 case Opt_noacl:
1615                         ext4_msg(sb, KERN_ERR, "(no)acl options not supported");
1616                         break;
1617 #endif
1618                 case Opt_journal_update:
1619                         /* @@@ FIXME */
1620                         /* Eventually we will want to be able to create
1621                            a journal file here.  For now, only allow the
1622                            user to specify an existing inode to be the
1623                            journal file. */
1624                         if (is_remount) {
1625                                 ext4_msg(sb, KERN_ERR,
1626                                          "Cannot specify journal on remount");
1627                                 return 0;
1628                         }
1629                         set_opt(sb, UPDATE_JOURNAL);
1630                         break;
1631                 case Opt_journal_dev:
1632                         if (is_remount) {
1633                                 ext4_msg(sb, KERN_ERR,
1634                                         "Cannot specify journal on remount");
1635                                 return 0;
1636                         }
1637                         if (match_int(&args[0], &option))
1638                                 return 0;
1639                         *journal_devnum = option;
1640                         break;
1641                 case Opt_journal_checksum:
1642                         set_opt(sb, JOURNAL_CHECKSUM);
1643                         break;
1644                 case Opt_journal_async_commit:
1645                         set_opt(sb, JOURNAL_ASYNC_COMMIT);
1646                         set_opt(sb, JOURNAL_CHECKSUM);
1647                         break;
1648                 case Opt_noload:
1649                         set_opt(sb, NOLOAD);
1650                         break;
1651                 case Opt_commit:
1652                         if (match_int(&args[0], &option))
1653                                 return 0;
1654                         if (option < 0)
1655                                 return 0;
1656                         if (option == 0)
1657                                 option = JBD2_DEFAULT_MAX_COMMIT_AGE;
1658                         sbi->s_commit_interval = HZ * option;
1659                         break;
1660                 case Opt_max_batch_time:
1661                         if (match_int(&args[0], &option))
1662                                 return 0;
1663                         if (option < 0)
1664                                 return 0;
1665                         if (option == 0)
1666                                 option = EXT4_DEF_MAX_BATCH_TIME;
1667                         sbi->s_max_batch_time = option;
1668                         break;
1669                 case Opt_min_batch_time:
1670                         if (match_int(&args[0], &option))
1671                                 return 0;
1672                         if (option < 0)
1673                                 return 0;
1674                         sbi->s_min_batch_time = option;
1675                         break;
1676                 case Opt_data_journal:
1677                         data_opt = EXT4_MOUNT_JOURNAL_DATA;
1678                         goto datacheck;
1679                 case Opt_data_ordered:
1680                         data_opt = EXT4_MOUNT_ORDERED_DATA;
1681                         goto datacheck;
1682                 case Opt_data_writeback:
1683                         data_opt = EXT4_MOUNT_WRITEBACK_DATA;
1684                 datacheck:
1685                         if (is_remount) {
1686                                 if (!sbi->s_journal)
1687                                         ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1688                                 else if (test_opt(sb, DATA_FLAGS) != data_opt) {
1689                                         ext4_msg(sb, KERN_ERR,
1690                                                 "Cannot change data mode on remount");
1691                                         return 0;
1692                                 }
1693                         } else {
1694                                 clear_opt(sb, DATA_FLAGS);
1695                                 sbi->s_mount_opt |= data_opt;
1696                         }
1697                         break;
1698                 case Opt_data_err_abort:
1699                         set_opt(sb, DATA_ERR_ABORT);
1700                         break;
1701                 case Opt_data_err_ignore:
1702                         clear_opt(sb, DATA_ERR_ABORT);
1703                         break;
1704 #ifdef CONFIG_QUOTA
1705                 case Opt_usrjquota:
1706                         if (!set_qf_name(sb, USRQUOTA, &args[0]))
1707                                 return 0;
1708                         break;
1709                 case Opt_grpjquota:
1710                         if (!set_qf_name(sb, GRPQUOTA, &args[0]))
1711                                 return 0;
1712                         break;
1713                 case Opt_offusrjquota:
1714                         if (!clear_qf_name(sb, USRQUOTA))
1715                                 return 0;
1716                         break;
1717                 case Opt_offgrpjquota:
1718                         if (!clear_qf_name(sb, GRPQUOTA))
1719                                 return 0;
1720                         break;
1721
1722                 case Opt_jqfmt_vfsold:
1723                         qfmt = QFMT_VFS_OLD;
1724                         goto set_qf_format;
1725                 case Opt_jqfmt_vfsv0:
1726                         qfmt = QFMT_VFS_V0;
1727                         goto set_qf_format;
1728                 case Opt_jqfmt_vfsv1:
1729                         qfmt = QFMT_VFS_V1;
1730 set_qf_format:
1731                         if (sb_any_quota_loaded(sb) &&
1732                             sbi->s_jquota_fmt != qfmt) {
1733                                 ext4_msg(sb, KERN_ERR, "Cannot change "
1734                                         "journaled quota options when "
1735                                         "quota turned on");
1736                                 return 0;
1737                         }
1738                         sbi->s_jquota_fmt = qfmt;
1739                         break;
1740                 case Opt_quota:
1741                 case Opt_usrquota:
1742                         set_opt(sb, QUOTA);
1743                         set_opt(sb, USRQUOTA);
1744                         break;
1745                 case Opt_grpquota:
1746                         set_opt(sb, QUOTA);
1747                         set_opt(sb, GRPQUOTA);
1748                         break;
1749                 case Opt_noquota:
1750                         if (sb_any_quota_loaded(sb)) {
1751                                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1752                                         "options when quota turned on");
1753                                 return 0;
1754                         }
1755                         clear_opt(sb, QUOTA);
1756                         clear_opt(sb, USRQUOTA);
1757                         clear_opt(sb, GRPQUOTA);
1758                         break;
1759 #else
1760                 case Opt_quota:
1761                 case Opt_usrquota:
1762                 case Opt_grpquota:
1763                         ext4_msg(sb, KERN_ERR,
1764                                 "quota options not supported");
1765                         break;
1766                 case Opt_usrjquota:
1767                 case Opt_grpjquota:
1768                 case Opt_offusrjquota:
1769                 case Opt_offgrpjquota:
1770                 case Opt_jqfmt_vfsold:
1771                 case Opt_jqfmt_vfsv0:
1772                 case Opt_jqfmt_vfsv1:
1773                         ext4_msg(sb, KERN_ERR,
1774                                 "journaled quota options not supported");
1775                         break;
1776                 case Opt_noquota:
1777                         break;
1778 #endif
1779                 case Opt_abort:
1780                         sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1781                         break;
1782                 case Opt_nobarrier:
1783                         clear_opt(sb, BARRIER);
1784                         break;
1785                 case Opt_barrier:
1786                         if (args[0].from) {
1787                                 if (match_int(&args[0], &option))
1788                                         return 0;
1789                         } else
1790                                 option = 1;     /* No argument, default to 1 */
1791                         if (option)
1792                                 set_opt(sb, BARRIER);
1793                         else
1794                                 clear_opt(sb, BARRIER);
1795                         break;
1796                 case Opt_ignore:
1797                         break;
1798                 case Opt_resize:
1799                         if (!is_remount) {
1800                                 ext4_msg(sb, KERN_ERR,
1801                                         "resize option only available "
1802                                         "for remount");
1803                                 return 0;
1804                         }
1805                         if (match_int(&args[0], &option) != 0)
1806                                 return 0;
1807                         *n_blocks_count = option;
1808                         break;
1809                 case Opt_nobh:
1810                         ext4_msg(sb, KERN_WARNING,
1811                                  "Ignoring deprecated nobh option");
1812                         break;
1813                 case Opt_bh:
1814                         ext4_msg(sb, KERN_WARNING,
1815                                  "Ignoring deprecated bh option");
1816                         break;
1817                 case Opt_i_version:
1818                         set_opt(sb, I_VERSION);
1819                         sb->s_flags |= MS_I_VERSION;
1820                         break;
1821                 case Opt_nodelalloc:
1822                         clear_opt(sb, DELALLOC);
1823                         clear_opt2(sb, EXPLICIT_DELALLOC);
1824                         break;
1825                 case Opt_mblk_io_submit:
1826                         set_opt(sb, MBLK_IO_SUBMIT);
1827                         break;
1828                 case Opt_nomblk_io_submit:
1829                         clear_opt(sb, MBLK_IO_SUBMIT);
1830                         break;
1831                 case Opt_stripe:
1832                         if (match_int(&args[0], &option))
1833                                 return 0;
1834                         if (option < 0)
1835                                 return 0;
1836                         sbi->s_stripe = option;
1837                         break;
1838                 case Opt_delalloc:
1839                         set_opt(sb, DELALLOC);
1840                         set_opt2(sb, EXPLICIT_DELALLOC);
1841                         break;
1842                 case Opt_block_validity:
1843                         set_opt(sb, BLOCK_VALIDITY);
1844                         break;
1845                 case Opt_noblock_validity:
1846                         clear_opt(sb, BLOCK_VALIDITY);
1847                         break;
1848                 case Opt_inode_readahead_blks:
1849                         if (match_int(&args[0], &option))
1850                                 return 0;
1851                         if (option < 0 || option > (1 << 30))
1852                                 return 0;
1853                         if (option && !is_power_of_2(option)) {
1854                                 ext4_msg(sb, KERN_ERR,
1855                                          "EXT4-fs: inode_readahead_blks"
1856                                          " must be a power of 2");
1857                                 return 0;
1858                         }
1859                         sbi->s_inode_readahead_blks = option;
1860                         break;
1861                 case Opt_journal_ioprio:
1862                         if (match_int(&args[0], &option))
1863                                 return 0;
1864                         if (option < 0 || option > 7)
1865                                 break;
1866                         *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE,
1867                                                             option);
1868                         break;
1869                 case Opt_noauto_da_alloc:
1870                         set_opt(sb, NO_AUTO_DA_ALLOC);
1871                         break;
1872                 case Opt_auto_da_alloc:
1873                         if (args[0].from) {
1874                                 if (match_int(&args[0], &option))
1875                                         return 0;
1876                         } else
1877                                 option = 1;     /* No argument, default to 1 */
1878                         if (option)
1879                                 clear_opt(sb, NO_AUTO_DA_ALLOC);
1880                         else
1881                                 set_opt(sb,NO_AUTO_DA_ALLOC);
1882                         break;
1883                 case Opt_discard:
1884                         set_opt(sb, DISCARD);
1885                         break;
1886                 case Opt_nodiscard:
1887                         clear_opt(sb, DISCARD);
1888                         break;
1889                 case Opt_dioread_nolock:
1890                         set_opt(sb, DIOREAD_NOLOCK);
1891                         break;
1892                 case Opt_dioread_lock:
1893                         clear_opt(sb, DIOREAD_NOLOCK);
1894                         break;
1895                 case Opt_init_itable:
1896                         set_opt(sb, INIT_INODE_TABLE);
1897                         if (args[0].from) {
1898                                 if (match_int(&args[0], &option))
1899                                         return 0;
1900                         } else
1901                                 option = EXT4_DEF_LI_WAIT_MULT;
1902                         if (option < 0)
1903                                 return 0;
1904                         sbi->s_li_wait_mult = option;
1905                         break;
1906                 case Opt_noinit_itable:
1907                         clear_opt(sb, INIT_INODE_TABLE);
1908                         break;
1909                 default:
1910                         ext4_msg(sb, KERN_ERR,
1911                                "Unrecognized mount option \"%s\" "
1912                                "or missing value", p);
1913                         return 0;
1914                 }
1915         }
1916 #ifdef CONFIG_QUOTA
1917         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1918                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1919                         clear_opt(sb, USRQUOTA);
1920
1921                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1922                         clear_opt(sb, GRPQUOTA);
1923
1924                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1925                         ext4_msg(sb, KERN_ERR, "old and new quota "
1926                                         "format mixing");
1927                         return 0;
1928                 }
1929
1930                 if (!sbi->s_jquota_fmt) {
1931                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1932                                         "not specified");
1933                         return 0;
1934                 }
1935         } else {
1936                 if (sbi->s_jquota_fmt) {
1937                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1938                                         "specified with no journaling "
1939                                         "enabled");
1940                         return 0;
1941                 }
1942         }
1943 #endif
1944         return 1;
1945 }
1946
1947 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1948                             int read_only)
1949 {
1950         struct ext4_sb_info *sbi = EXT4_SB(sb);
1951         int res = 0;
1952
1953         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1954                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1955                          "forcing read-only mode");
1956                 res = MS_RDONLY;
1957         }
1958         if (read_only)
1959                 goto done;
1960         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1961                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1962                          "running e2fsck is recommended");
1963         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1964                 ext4_msg(sb, KERN_WARNING,
1965                          "warning: mounting fs with errors, "
1966                          "running e2fsck is recommended");
1967         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1968                  le16_to_cpu(es->s_mnt_count) >=
1969                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1970                 ext4_msg(sb, KERN_WARNING,
1971                          "warning: maximal mount count reached, "
1972                          "running e2fsck is recommended");
1973         else if (le32_to_cpu(es->s_checkinterval) &&
1974                 (le32_to_cpu(es->s_lastcheck) +
1975                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1976                 ext4_msg(sb, KERN_WARNING,
1977                          "warning: checktime reached, "
1978                          "running e2fsck is recommended");
1979         if (!sbi->s_journal)
1980                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1981         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1982                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1983         le16_add_cpu(&es->s_mnt_count, 1);
1984         es->s_mtime = cpu_to_le32(get_seconds());
1985         ext4_update_dynamic_rev(sb);
1986         if (sbi->s_journal)
1987                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1988
1989         ext4_commit_super(sb, 1);
1990 done:
1991         if (test_opt(sb, DEBUG))
1992                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1993                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1994                         sb->s_blocksize,
1995                         sbi->s_groups_count,
1996                         EXT4_BLOCKS_PER_GROUP(sb),
1997                         EXT4_INODES_PER_GROUP(sb),
1998                         sbi->s_mount_opt, sbi->s_mount_opt2);
1999
2000         cleancache_init_fs(sb);
2001         return res;
2002 }
2003
2004 static int ext4_fill_flex_info(struct super_block *sb)
2005 {
2006         struct ext4_sb_info *sbi = EXT4_SB(sb);
2007         struct ext4_group_desc *gdp = NULL;
2008         ext4_group_t flex_group_count;
2009         ext4_group_t flex_group;
2010         unsigned int groups_per_flex = 0;
2011         size_t size;
2012         int i;
2013
2014         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2015         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2016                 sbi->s_log_groups_per_flex = 0;
2017                 return 1;
2018         }
2019         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
2020
2021         /* We allocate both existing and potentially added groups */
2022         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
2023                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
2024                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
2025         size = flex_group_count * sizeof(struct flex_groups);
2026         sbi->s_flex_groups = ext4_kvzalloc(size, GFP_KERNEL);
2027         if (sbi->s_flex_groups == NULL) {
2028                 ext4_msg(sb, KERN_ERR, "not enough memory for %u flex groups",
2029                          flex_group_count);
2030                 goto failed;
2031         }
2032
2033         for (i = 0; i < sbi->s_groups_count; i++) {
2034                 gdp = ext4_get_group_desc(sb, i, NULL);
2035
2036                 flex_group = ext4_flex_group(sbi, i);
2037                 atomic_add(ext4_free_inodes_count(sb, gdp),
2038                            &sbi->s_flex_groups[flex_group].free_inodes);
2039                 atomic_add(ext4_free_group_clusters(sb, gdp),
2040                            &sbi->s_flex_groups[flex_group].free_clusters);
2041                 atomic_add(ext4_used_dirs_count(sb, gdp),
2042                            &sbi->s_flex_groups[flex_group].used_dirs);
2043         }
2044
2045         return 1;
2046 failed:
2047         return 0;
2048 }
2049
2050 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
2051                             struct ext4_group_desc *gdp)
2052 {
2053         __u16 crc = 0;
2054
2055         if (sbi->s_es->s_feature_ro_compat &
2056             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
2057                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
2058                 __le32 le_group = cpu_to_le32(block_group);
2059
2060                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2061                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2062                 crc = crc16(crc, (__u8 *)gdp, offset);
2063                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
2064                 /* for checksum of struct ext4_group_desc do the rest...*/
2065                 if ((sbi->s_es->s_feature_incompat &
2066                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2067                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
2068                         crc = crc16(crc, (__u8 *)gdp + offset,
2069                                     le16_to_cpu(sbi->s_es->s_desc_size) -
2070                                         offset);
2071         }
2072
2073         return cpu_to_le16(crc);
2074 }
2075
2076 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
2077                                 struct ext4_group_desc *gdp)
2078 {
2079         if ((sbi->s_es->s_feature_ro_compat &
2080              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
2081             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
2082                 return 0;
2083
2084         return 1;
2085 }
2086
2087 /* Called at mount-time, super-block is locked */
2088 static int ext4_check_descriptors(struct super_block *sb,
2089                                   ext4_group_t *first_not_zeroed)
2090 {
2091         struct ext4_sb_info *sbi = EXT4_SB(sb);
2092         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2093         ext4_fsblk_t last_block;
2094         ext4_fsblk_t block_bitmap;
2095         ext4_fsblk_t inode_bitmap;
2096         ext4_fsblk_t inode_table;
2097         int flexbg_flag = 0;
2098         ext4_group_t i, grp = sbi->s_groups_count;
2099
2100         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2101                 flexbg_flag = 1;
2102
2103         ext4_debug("Checking group descriptors");
2104
2105         for (i = 0; i < sbi->s_groups_count; i++) {
2106                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2107
2108                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2109                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2110                 else
2111                         last_block = first_block +
2112                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2113
2114                 if ((grp == sbi->s_groups_count) &&
2115                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2116                         grp = i;
2117
2118                 block_bitmap = ext4_block_bitmap(sb, gdp);
2119                 if (block_bitmap < first_block || block_bitmap > last_block) {
2120                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2121                                "Block bitmap for group %u not in group "
2122                                "(block %llu)!", i, block_bitmap);
2123                         return 0;
2124                 }
2125                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2126                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2127                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2128                                "Inode bitmap for group %u not in group "
2129                                "(block %llu)!", i, inode_bitmap);
2130                         return 0;
2131                 }
2132                 inode_table = ext4_inode_table(sb, gdp);
2133                 if (inode_table < first_block ||
2134                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2135                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2136                                "Inode table for group %u not in group "
2137                                "(block %llu)!", i, inode_table);
2138                         return 0;
2139                 }
2140                 ext4_lock_group(sb, i);
2141                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
2142                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2143                                  "Checksum for group %u failed (%u!=%u)",
2144                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2145                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2146                         if (!(sb->s_flags & MS_RDONLY)) {
2147                                 ext4_unlock_group(sb, i);
2148                                 return 0;
2149                         }
2150                 }
2151                 ext4_unlock_group(sb, i);
2152                 if (!flexbg_flag)
2153                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2154         }
2155         if (NULL != first_not_zeroed)
2156                 *first_not_zeroed = grp;
2157
2158         ext4_free_blocks_count_set(sbi->s_es,
2159                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2160         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2161         return 1;
2162 }
2163
2164 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2165  * the superblock) which were deleted from all directories, but held open by
2166  * a process at the time of a crash.  We walk the list and try to delete these
2167  * inodes at recovery time (only with a read-write filesystem).
2168  *
2169  * In order to keep the orphan inode chain consistent during traversal (in
2170  * case of crash during recovery), we link each inode into the superblock
2171  * orphan list_head and handle it the same way as an inode deletion during
2172  * normal operation (which journals the operations for us).
2173  *
2174  * We only do an iget() and an iput() on each inode, which is very safe if we
2175  * accidentally point at an in-use or already deleted inode.  The worst that
2176  * can happen in this case is that we get a "bit already cleared" message from
2177  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2178  * e2fsck was run on this filesystem, and it must have already done the orphan
2179  * inode cleanup for us, so we can safely abort without any further action.
2180  */
2181 static void ext4_orphan_cleanup(struct super_block *sb,
2182                                 struct ext4_super_block *es)
2183 {
2184         unsigned int s_flags = sb->s_flags;
2185         int nr_orphans = 0, nr_truncates = 0;
2186 #ifdef CONFIG_QUOTA
2187         int i;
2188 #endif
2189         if (!es->s_last_orphan) {
2190                 jbd_debug(4, "no orphan inodes to clean up\n");
2191                 return;
2192         }
2193
2194         if (bdev_read_only(sb->s_bdev)) {
2195                 ext4_msg(sb, KERN_ERR, "write access "
2196                         "unavailable, skipping orphan cleanup");
2197                 return;
2198         }
2199
2200         /* Check if feature set would not allow a r/w mount */
2201         if (!ext4_feature_set_ok(sb, 0)) {
2202                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2203                          "unknown ROCOMPAT features");
2204                 return;
2205         }
2206
2207         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2208                 if (es->s_last_orphan)
2209                         jbd_debug(1, "Errors on filesystem, "
2210                                   "clearing orphan list.\n");
2211                 es->s_last_orphan = 0;
2212                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2213                 return;
2214         }
2215
2216         if (s_flags & MS_RDONLY) {
2217                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2218                 sb->s_flags &= ~MS_RDONLY;
2219         }
2220 #ifdef CONFIG_QUOTA
2221         /* Needed for iput() to work correctly and not trash data */
2222         sb->s_flags |= MS_ACTIVE;
2223         /* Turn on quotas so that they are updated correctly */
2224         for (i = 0; i < MAXQUOTAS; i++) {
2225                 if (EXT4_SB(sb)->s_qf_names[i]) {
2226                         int ret = ext4_quota_on_mount(sb, i);
2227                         if (ret < 0)
2228                                 ext4_msg(sb, KERN_ERR,
2229                                         "Cannot turn on journaled "
2230                                         "quota: error %d", ret);
2231                 }
2232         }
2233 #endif
2234
2235         while (es->s_last_orphan) {
2236                 struct inode *inode;
2237
2238                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2239                 if (IS_ERR(inode)) {
2240                         es->s_last_orphan = 0;
2241                         break;
2242                 }
2243
2244                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2245                 dquot_initialize(inode);
2246                 if (inode->i_nlink) {
2247                         ext4_msg(sb, KERN_DEBUG,
2248                                 "%s: truncating inode %lu to %lld bytes",
2249                                 __func__, inode->i_ino, inode->i_size);
2250                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2251                                   inode->i_ino, inode->i_size);
2252                         ext4_truncate(inode);
2253                         nr_truncates++;
2254                 } else {
2255                         ext4_msg(sb, KERN_DEBUG,
2256                                 "%s: deleting unreferenced inode %lu",
2257                                 __func__, inode->i_ino);
2258                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2259                                   inode->i_ino);
2260                         nr_orphans++;
2261                 }
2262                 iput(inode);  /* The delete magic happens here! */
2263         }
2264
2265 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2266
2267         if (nr_orphans)
2268                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2269                        PLURAL(nr_orphans));
2270         if (nr_truncates)
2271                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2272                        PLURAL(nr_truncates));
2273 #ifdef CONFIG_QUOTA
2274         /* Turn quotas off */
2275         for (i = 0; i < MAXQUOTAS; i++) {
2276                 if (sb_dqopt(sb)->files[i])
2277                         dquot_quota_off(sb, i);
2278         }
2279 #endif
2280         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2281 }
2282
2283 /*
2284  * Maximal extent format file size.
2285  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2286  * extent format containers, within a sector_t, and within i_blocks
2287  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2288  * so that won't be a limiting factor.
2289  *
2290  * However there is other limiting factor. We do store extents in the form
2291  * of starting block and length, hence the resulting length of the extent
2292  * covering maximum file size must fit into on-disk format containers as
2293  * well. Given that length is always by 1 unit bigger than max unit (because
2294  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2295  *
2296  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2297  */
2298 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2299 {
2300         loff_t res;
2301         loff_t upper_limit = MAX_LFS_FILESIZE;
2302
2303         /* small i_blocks in vfs inode? */
2304         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2305                 /*
2306                  * CONFIG_LBDAF is not enabled implies the inode
2307                  * i_block represent total blocks in 512 bytes
2308                  * 32 == size of vfs inode i_blocks * 8
2309                  */
2310                 upper_limit = (1LL << 32) - 1;
2311
2312                 /* total blocks in file system block size */
2313                 upper_limit >>= (blkbits - 9);
2314                 upper_limit <<= blkbits;
2315         }
2316
2317         /*
2318          * 32-bit extent-start container, ee_block. We lower the maxbytes
2319          * by one fs block, so ee_len can cover the extent of maximum file
2320          * size
2321          */
2322         res = (1LL << 32) - 1;
2323         res <<= blkbits;
2324
2325         /* Sanity check against vm- & vfs- imposed limits */
2326         if (res > upper_limit)
2327                 res = upper_limit;
2328
2329         return res;
2330 }
2331
2332 /*
2333  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2334  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2335  * We need to be 1 filesystem block less than the 2^48 sector limit.
2336  */
2337 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2338 {
2339         loff_t res = EXT4_NDIR_BLOCKS;
2340         int meta_blocks;
2341         loff_t upper_limit;
2342         /* This is calculated to be the largest file size for a dense, block
2343          * mapped file such that the file's total number of 512-byte sectors,
2344          * including data and all indirect blocks, does not exceed (2^48 - 1).
2345          *
2346          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2347          * number of 512-byte sectors of the file.
2348          */
2349
2350         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2351                 /*
2352                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2353                  * the inode i_block field represents total file blocks in
2354                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2355                  */
2356                 upper_limit = (1LL << 32) - 1;
2357
2358                 /* total blocks in file system block size */
2359                 upper_limit >>= (bits - 9);
2360
2361         } else {
2362                 /*
2363                  * We use 48 bit ext4_inode i_blocks
2364                  * With EXT4_HUGE_FILE_FL set the i_blocks
2365                  * represent total number of blocks in
2366                  * file system block size
2367                  */
2368                 upper_limit = (1LL << 48) - 1;
2369
2370         }
2371
2372         /* indirect blocks */
2373         meta_blocks = 1;
2374         /* double indirect blocks */
2375         meta_blocks += 1 + (1LL << (bits-2));
2376         /* tripple indirect blocks */
2377         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2378
2379         upper_limit -= meta_blocks;
2380         upper_limit <<= bits;
2381
2382         res += 1LL << (bits-2);
2383         res += 1LL << (2*(bits-2));
2384         res += 1LL << (3*(bits-2));
2385         res <<= bits;
2386         if (res > upper_limit)
2387                 res = upper_limit;
2388
2389         if (res > MAX_LFS_FILESIZE)
2390                 res = MAX_LFS_FILESIZE;
2391
2392         return res;
2393 }
2394
2395 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2396                                    ext4_fsblk_t logical_sb_block, int nr)
2397 {
2398         struct ext4_sb_info *sbi = EXT4_SB(sb);
2399         ext4_group_t bg, first_meta_bg;
2400         int has_super = 0;
2401
2402         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2403
2404         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2405             nr < first_meta_bg)
2406                 return logical_sb_block + nr + 1;
2407         bg = sbi->s_desc_per_block * nr;
2408         if (ext4_bg_has_super(sb, bg))
2409                 has_super = 1;
2410
2411         return (has_super + ext4_group_first_block_no(sb, bg));
2412 }
2413
2414 /**
2415  * ext4_get_stripe_size: Get the stripe size.
2416  * @sbi: In memory super block info
2417  *
2418  * If we have specified it via mount option, then
2419  * use the mount option value. If the value specified at mount time is
2420  * greater than the blocks per group use the super block value.
2421  * If the super block value is greater than blocks per group return 0.
2422  * Allocator needs it be less than blocks per group.
2423  *
2424  */
2425 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2426 {
2427         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2428         unsigned long stripe_width =
2429                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2430         int ret;
2431
2432         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2433                 ret = sbi->s_stripe;
2434         else if (stripe_width <= sbi->s_blocks_per_group)
2435                 ret = stripe_width;
2436         else if (stride <= sbi->s_blocks_per_group)
2437                 ret = stride;
2438         else
2439                 ret = 0;
2440
2441         /*
2442          * If the stripe width is 1, this makes no sense and
2443          * we set it to 0 to turn off stripe handling code.
2444          */
2445         if (ret <= 1)
2446                 ret = 0;
2447
2448         return ret;
2449 }
2450
2451 /* sysfs supprt */
2452
2453 struct ext4_attr {
2454         struct attribute attr;
2455         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2456         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2457                          const char *, size_t);
2458         int offset;
2459 };
2460
2461 static int parse_strtoul(const char *buf,
2462                 unsigned long max, unsigned long *value)
2463 {
2464         char *endp;
2465
2466         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2467         endp = skip_spaces(endp);
2468         if (*endp || *value > max)
2469                 return -EINVAL;
2470
2471         return 0;
2472 }
2473
2474 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2475                                               struct ext4_sb_info *sbi,
2476                                               char *buf)
2477 {
2478         return snprintf(buf, PAGE_SIZE, "%llu\n",
2479                 (s64) EXT4_C2B(sbi,
2480                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2481 }
2482
2483 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2484                                          struct ext4_sb_info *sbi, char *buf)
2485 {
2486         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2487
2488         if (!sb->s_bdev->bd_part)
2489                 return snprintf(buf, PAGE_SIZE, "0\n");
2490         return snprintf(buf, PAGE_SIZE, "%lu\n",
2491                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2492                          sbi->s_sectors_written_start) >> 1);
2493 }
2494
2495 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2496                                           struct ext4_sb_info *sbi, char *buf)
2497 {
2498         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2499
2500         if (!sb->s_bdev->bd_part)
2501                 return snprintf(buf, PAGE_SIZE, "0\n");
2502         return snprintf(buf, PAGE_SIZE, "%llu\n",
2503                         (unsigned long long)(sbi->s_kbytes_written +
2504                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2505                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2506 }
2507
2508 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2509                                           struct ext4_sb_info *sbi,
2510                                           const char *buf, size_t count)
2511 {
2512         unsigned long t;
2513
2514         if (parse_strtoul(buf, 0x40000000, &t))
2515                 return -EINVAL;
2516
2517         if (t && !is_power_of_2(t))
2518                 return -EINVAL;
2519
2520         sbi->s_inode_readahead_blks = t;
2521         return count;
2522 }
2523
2524 static ssize_t sbi_ui_show(struct ext4_attr *a,
2525                            struct ext4_sb_info *sbi, char *buf)
2526 {
2527         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2528
2529         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2530 }
2531
2532 static ssize_t sbi_ui_store(struct ext4_attr *a,
2533                             struct ext4_sb_info *sbi,
2534                             const char *buf, size_t count)
2535 {
2536         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2537         unsigned long t;
2538
2539         if (parse_strtoul(buf, 0xffffffff, &t))
2540                 return -EINVAL;
2541         *ui = t;
2542         return count;
2543 }
2544
2545 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2546 static struct ext4_attr ext4_attr_##_name = {                   \
2547         .attr = {.name = __stringify(_name), .mode = _mode },   \
2548         .show   = _show,                                        \
2549         .store  = _store,                                       \
2550         .offset = offsetof(struct ext4_sb_info, _elname),       \
2551 }
2552 #define EXT4_ATTR(name, mode, show, store) \
2553 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2554
2555 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2556 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2557 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2558 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2559         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2560 #define ATTR_LIST(name) &ext4_attr_##name.attr
2561
2562 EXT4_RO_ATTR(delayed_allocation_blocks);
2563 EXT4_RO_ATTR(session_write_kbytes);
2564 EXT4_RO_ATTR(lifetime_write_kbytes);
2565 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2566                  inode_readahead_blks_store, s_inode_readahead_blks);
2567 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2568 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2569 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2570 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2571 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2572 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2573 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2574 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2575
2576 static struct attribute *ext4_attrs[] = {
2577         ATTR_LIST(delayed_allocation_blocks),
2578         ATTR_LIST(session_write_kbytes),
2579         ATTR_LIST(lifetime_write_kbytes),
2580         ATTR_LIST(inode_readahead_blks),
2581         ATTR_LIST(inode_goal),
2582         ATTR_LIST(mb_stats),
2583         ATTR_LIST(mb_max_to_scan),
2584         ATTR_LIST(mb_min_to_scan),
2585         ATTR_LIST(mb_order2_req),
2586         ATTR_LIST(mb_stream_req),
2587         ATTR_LIST(mb_group_prealloc),
2588         ATTR_LIST(max_writeback_mb_bump),
2589         NULL,
2590 };
2591
2592 /* Features this copy of ext4 supports */
2593 EXT4_INFO_ATTR(lazy_itable_init);
2594 EXT4_INFO_ATTR(batched_discard);
2595
2596 static struct attribute *ext4_feat_attrs[] = {
2597         ATTR_LIST(lazy_itable_init),
2598         ATTR_LIST(batched_discard),
2599         NULL,
2600 };
2601
2602 static ssize_t ext4_attr_show(struct kobject *kobj,
2603                               struct attribute *attr, char *buf)
2604 {
2605         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2606                                                 s_kobj);
2607         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2608
2609         return a->show ? a->show(a, sbi, buf) : 0;
2610 }
2611
2612 static ssize_t ext4_attr_store(struct kobject *kobj,
2613                                struct attribute *attr,
2614                                const char *buf, size_t len)
2615 {
2616         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2617                                                 s_kobj);
2618         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2619
2620         return a->store ? a->store(a, sbi, buf, len) : 0;
2621 }
2622
2623 static void ext4_sb_release(struct kobject *kobj)
2624 {
2625         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2626                                                 s_kobj);
2627         complete(&sbi->s_kobj_unregister);
2628 }
2629
2630 static const struct sysfs_ops ext4_attr_ops = {
2631         .show   = ext4_attr_show,
2632         .store  = ext4_attr_store,
2633 };
2634
2635 static struct kobj_type ext4_ktype = {
2636         .default_attrs  = ext4_attrs,
2637         .sysfs_ops      = &ext4_attr_ops,
2638         .release        = ext4_sb_release,
2639 };
2640
2641 static void ext4_feat_release(struct kobject *kobj)
2642 {
2643         complete(&ext4_feat->f_kobj_unregister);
2644 }
2645
2646 static struct kobj_type ext4_feat_ktype = {
2647         .default_attrs  = ext4_feat_attrs,
2648         .sysfs_ops      = &ext4_attr_ops,
2649         .release        = ext4_feat_release,
2650 };
2651
2652 /*
2653  * Check whether this filesystem can be mounted based on
2654  * the features present and the RDONLY/RDWR mount requested.
2655  * Returns 1 if this filesystem can be mounted as requested,
2656  * 0 if it cannot be.
2657  */
2658 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2659 {
2660         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2661                 ext4_msg(sb, KERN_ERR,
2662                         "Couldn't mount because of "
2663                         "unsupported optional features (%x)",
2664                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2665                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2666                 return 0;
2667         }
2668
2669         if (readonly)
2670                 return 1;
2671
2672         /* Check that feature set is OK for a read-write mount */
2673         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2674                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2675                          "unsupported optional features (%x)",
2676                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2677                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2678                 return 0;
2679         }
2680         /*
2681          * Large file size enabled file system can only be mounted
2682          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2683          */
2684         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2685                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2686                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2687                                  "cannot be mounted RDWR without "
2688                                  "CONFIG_LBDAF");
2689                         return 0;
2690                 }
2691         }
2692         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2693             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2694                 ext4_msg(sb, KERN_ERR,
2695                          "Can't support bigalloc feature without "
2696                          "extents feature\n");
2697                 return 0;
2698         }
2699         return 1;
2700 }
2701
2702 /*
2703  * This function is called once a day if we have errors logged
2704  * on the file system
2705  */
2706 static void print_daily_error_info(unsigned long arg)
2707 {
2708         struct super_block *sb = (struct super_block *) arg;
2709         struct ext4_sb_info *sbi;
2710         struct ext4_super_block *es;
2711
2712         sbi = EXT4_SB(sb);
2713         es = sbi->s_es;
2714
2715         if (es->s_error_count)
2716                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2717                          le32_to_cpu(es->s_error_count));
2718         if (es->s_first_error_time) {
2719                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2720                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2721                        (int) sizeof(es->s_first_error_func),
2722                        es->s_first_error_func,
2723                        le32_to_cpu(es->s_first_error_line));
2724                 if (es->s_first_error_ino)
2725                         printk(": inode %u",
2726                                le32_to_cpu(es->s_first_error_ino));
2727                 if (es->s_first_error_block)
2728                         printk(": block %llu", (unsigned long long)
2729                                le64_to_cpu(es->s_first_error_block));
2730                 printk("\n");
2731         }
2732         if (es->s_last_error_time) {
2733                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2734                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2735                        (int) sizeof(es->s_last_error_func),
2736                        es->s_last_error_func,
2737                        le32_to_cpu(es->s_last_error_line));
2738                 if (es->s_last_error_ino)
2739                         printk(": inode %u",
2740                                le32_to_cpu(es->s_last_error_ino));
2741                 if (es->s_last_error_block)
2742                         printk(": block %llu", (unsigned long long)
2743                                le64_to_cpu(es->s_last_error_block));
2744                 printk("\n");
2745         }
2746         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2747 }
2748
2749 /* Find next suitable group and run ext4_init_inode_table */
2750 static int ext4_run_li_request(struct ext4_li_request *elr)
2751 {
2752         struct ext4_group_desc *gdp = NULL;
2753         ext4_group_t group, ngroups;
2754         struct super_block *sb;
2755         unsigned long timeout = 0;
2756         int ret = 0;
2757
2758         sb = elr->lr_super;
2759         ngroups = EXT4_SB(sb)->s_groups_count;
2760
2761         for (group = elr->lr_next_group; group < ngroups; group++) {
2762                 gdp = ext4_get_group_desc(sb, group, NULL);
2763                 if (!gdp) {
2764                         ret = 1;
2765                         break;
2766                 }
2767
2768                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2769                         break;
2770         }
2771
2772         if (group == ngroups)
2773                 ret = 1;
2774
2775         if (!ret) {
2776                 timeout = jiffies;
2777                 ret = ext4_init_inode_table(sb, group,
2778                                             elr->lr_timeout ? 0 : 1);
2779                 if (elr->lr_timeout == 0) {
2780                         timeout = (jiffies - timeout) *
2781                                   elr->lr_sbi->s_li_wait_mult;
2782                         elr->lr_timeout = timeout;
2783                 }
2784                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2785                 elr->lr_next_group = group + 1;
2786         }
2787
2788         return ret;
2789 }
2790
2791 /*
2792  * Remove lr_request from the list_request and free the
2793  * request structure. Should be called with li_list_mtx held
2794  */
2795 static void ext4_remove_li_request(struct ext4_li_request *elr)
2796 {
2797         struct ext4_sb_info *sbi;
2798
2799         if (!elr)
2800                 return;
2801
2802         sbi = elr->lr_sbi;
2803
2804         list_del(&elr->lr_request);
2805         sbi->s_li_request = NULL;
2806         kfree(elr);
2807 }
2808
2809 static void ext4_unregister_li_request(struct super_block *sb)
2810 {
2811         mutex_lock(&ext4_li_mtx);
2812         if (!ext4_li_info) {
2813                 mutex_unlock(&ext4_li_mtx);
2814                 return;
2815         }
2816
2817         mutex_lock(&ext4_li_info->li_list_mtx);
2818         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2819         mutex_unlock(&ext4_li_info->li_list_mtx);
2820         mutex_unlock(&ext4_li_mtx);
2821 }
2822
2823 static struct task_struct *ext4_lazyinit_task;
2824
2825 /*
2826  * This is the function where ext4lazyinit thread lives. It walks
2827  * through the request list searching for next scheduled filesystem.
2828  * When such a fs is found, run the lazy initialization request
2829  * (ext4_rn_li_request) and keep track of the time spend in this
2830  * function. Based on that time we compute next schedule time of
2831  * the request. When walking through the list is complete, compute
2832  * next waking time and put itself into sleep.
2833  */
2834 static int ext4_lazyinit_thread(void *arg)
2835 {
2836         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2837         struct list_head *pos, *n;
2838         struct ext4_li_request *elr;
2839         unsigned long next_wakeup, cur;
2840
2841         BUG_ON(NULL == eli);
2842
2843 cont_thread:
2844         while (true) {
2845                 next_wakeup = MAX_JIFFY_OFFSET;
2846
2847                 mutex_lock(&eli->li_list_mtx);
2848                 if (list_empty(&eli->li_request_list)) {
2849                         mutex_unlock(&eli->li_list_mtx);
2850                         goto exit_thread;
2851                 }
2852
2853                 list_for_each_safe(pos, n, &eli->li_request_list) {
2854                         elr = list_entry(pos, struct ext4_li_request,
2855                                          lr_request);
2856
2857                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2858                                 if (ext4_run_li_request(elr) != 0) {
2859                                         /* error, remove the lazy_init job */
2860                                         ext4_remove_li_request(elr);
2861                                         continue;
2862                                 }
2863                         }
2864
2865                         if (time_before(elr->lr_next_sched, next_wakeup))
2866                                 next_wakeup = elr->lr_next_sched;
2867                 }
2868                 mutex_unlock(&eli->li_list_mtx);
2869
2870                 if (freezing(current))
2871                         refrigerator();
2872
2873                 cur = jiffies;
2874                 if ((time_after_eq(cur, next_wakeup)) ||
2875                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2876                         cond_resched();
2877                         continue;
2878                 }
2879
2880                 schedule_timeout_interruptible(next_wakeup - cur);
2881
2882                 if (kthread_should_stop()) {
2883                         ext4_clear_request_list();
2884                         goto exit_thread;
2885                 }
2886         }
2887
2888 exit_thread:
2889         /*
2890          * It looks like the request list is empty, but we need
2891          * to check it under the li_list_mtx lock, to prevent any
2892          * additions into it, and of course we should lock ext4_li_mtx
2893          * to atomically free the list and ext4_li_info, because at
2894          * this point another ext4 filesystem could be registering
2895          * new one.
2896          */
2897         mutex_lock(&ext4_li_mtx);
2898         mutex_lock(&eli->li_list_mtx);
2899         if (!list_empty(&eli->li_request_list)) {
2900                 mutex_unlock(&eli->li_list_mtx);
2901                 mutex_unlock(&ext4_li_mtx);
2902                 goto cont_thread;
2903         }
2904         mutex_unlock(&eli->li_list_mtx);
2905         kfree(ext4_li_info);
2906         ext4_li_info = NULL;
2907         mutex_unlock(&ext4_li_mtx);
2908
2909         return 0;
2910 }
2911
2912 static void ext4_clear_request_list(void)
2913 {
2914         struct list_head *pos, *n;
2915         struct ext4_li_request *elr;
2916
2917         mutex_lock(&ext4_li_info->li_list_mtx);
2918         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2919                 elr = list_entry(pos, struct ext4_li_request,
2920                                  lr_request);
2921                 ext4_remove_li_request(elr);
2922         }
2923         mutex_unlock(&ext4_li_info->li_list_mtx);
2924 }
2925
2926 static int ext4_run_lazyinit_thread(void)
2927 {
2928         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2929                                          ext4_li_info, "ext4lazyinit");
2930         if (IS_ERR(ext4_lazyinit_task)) {
2931                 int err = PTR_ERR(ext4_lazyinit_task);
2932                 ext4_clear_request_list();
2933                 kfree(ext4_li_info);
2934                 ext4_li_info = NULL;
2935                 printk(KERN_CRIT "EXT4: error %d creating inode table "
2936                                  "initialization thread\n",
2937                                  err);
2938                 return err;
2939         }
2940         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2941         return 0;
2942 }
2943
2944 /*
2945  * Check whether it make sense to run itable init. thread or not.
2946  * If there is at least one uninitialized inode table, return
2947  * corresponding group number, else the loop goes through all
2948  * groups and return total number of groups.
2949  */
2950 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2951 {
2952         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2953         struct ext4_group_desc *gdp = NULL;
2954
2955         for (group = 0; group < ngroups; group++) {
2956                 gdp = ext4_get_group_desc(sb, group, NULL);
2957                 if (!gdp)
2958                         continue;
2959
2960                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2961                         break;
2962         }
2963
2964         return group;
2965 }
2966
2967 static int ext4_li_info_new(void)
2968 {
2969         struct ext4_lazy_init *eli = NULL;
2970
2971         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2972         if (!eli)
2973                 return -ENOMEM;
2974
2975         INIT_LIST_HEAD(&eli->li_request_list);
2976         mutex_init(&eli->li_list_mtx);
2977
2978         eli->li_state |= EXT4_LAZYINIT_QUIT;
2979
2980         ext4_li_info = eli;
2981
2982         return 0;
2983 }
2984
2985 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2986                                             ext4_group_t start)
2987 {
2988         struct ext4_sb_info *sbi = EXT4_SB(sb);
2989         struct ext4_li_request *elr;
2990         unsigned long rnd;
2991
2992         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2993         if (!elr)
2994                 return NULL;
2995
2996         elr->lr_super = sb;
2997         elr->lr_sbi = sbi;
2998         elr->lr_next_group = start;
2999
3000         /*
3001          * Randomize first schedule time of the request to
3002          * spread the inode table initialization requests
3003          * better.
3004          */
3005         get_random_bytes(&rnd, sizeof(rnd));
3006         elr->lr_next_sched = jiffies + (unsigned long)rnd %
3007                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
3008
3009         return elr;
3010 }
3011
3012 static int ext4_register_li_request(struct super_block *sb,
3013                                     ext4_group_t first_not_zeroed)
3014 {
3015         struct ext4_sb_info *sbi = EXT4_SB(sb);
3016         struct ext4_li_request *elr;
3017         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3018         int ret = 0;
3019
3020         if (sbi->s_li_request != NULL) {
3021                 /*
3022                  * Reset timeout so it can be computed again, because
3023                  * s_li_wait_mult might have changed.
3024                  */
3025                 sbi->s_li_request->lr_timeout = 0;
3026                 return 0;
3027         }
3028
3029         if (first_not_zeroed == ngroups ||
3030             (sb->s_flags & MS_RDONLY) ||
3031             !test_opt(sb, INIT_INODE_TABLE))
3032                 return 0;
3033
3034         elr = ext4_li_request_new(sb, first_not_zeroed);
3035         if (!elr)
3036                 return -ENOMEM;
3037
3038         mutex_lock(&ext4_li_mtx);
3039
3040         if (NULL == ext4_li_info) {
3041                 ret = ext4_li_info_new();
3042                 if (ret)
3043                         goto out;
3044         }
3045
3046         mutex_lock(&ext4_li_info->li_list_mtx);
3047         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3048         mutex_unlock(&ext4_li_info->li_list_mtx);
3049
3050         sbi->s_li_request = elr;
3051         /*
3052          * set elr to NULL here since it has been inserted to
3053          * the request_list and the removal and free of it is
3054          * handled by ext4_clear_request_list from now on.
3055          */
3056         elr = NULL;
3057
3058         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3059                 ret = ext4_run_lazyinit_thread();
3060                 if (ret)
3061                         goto out;
3062         }
3063 out:
3064         mutex_unlock(&ext4_li_mtx);
3065         if (ret)
3066                 kfree(elr);
3067         return ret;
3068 }
3069
3070 /*
3071  * We do not need to lock anything since this is called on
3072  * module unload.
3073  */
3074 static void ext4_destroy_lazyinit_thread(void)
3075 {
3076         /*
3077          * If thread exited earlier
3078          * there's nothing to be done.
3079          */
3080         if (!ext4_li_info || !ext4_lazyinit_task)
3081                 return;
3082
3083         kthread_stop(ext4_lazyinit_task);
3084 }
3085
3086 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3087 {
3088         char *orig_data = kstrdup(data, GFP_KERNEL);
3089         struct buffer_head *bh;
3090         struct ext4_super_block *es = NULL;
3091         struct ext4_sb_info *sbi;
3092         ext4_fsblk_t block;
3093         ext4_fsblk_t sb_block = get_sb_block(&data);
3094         ext4_fsblk_t logical_sb_block;
3095         unsigned long offset = 0;
3096         unsigned long journal_devnum = 0;
3097         unsigned long def_mount_opts;
3098         struct inode *root;
3099         char *cp;
3100         const char *descr;
3101         int ret = -ENOMEM;
3102         int blocksize, clustersize;
3103         unsigned int db_count;
3104         unsigned int i;
3105         int needs_recovery, has_huge_files, has_bigalloc;
3106         __u64 blocks_count;
3107         int err;
3108         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3109         ext4_group_t first_not_zeroed;
3110
3111         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3112         if (!sbi)
3113                 goto out_free_orig;
3114
3115         sbi->s_blockgroup_lock =
3116                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3117         if (!sbi->s_blockgroup_lock) {
3118                 kfree(sbi);
3119                 goto out_free_orig;
3120         }
3121         sb->s_fs_info = sbi;
3122         sbi->s_mount_opt = 0;
3123         sbi->s_resuid = EXT4_DEF_RESUID;
3124         sbi->s_resgid = EXT4_DEF_RESGID;
3125         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3126         sbi->s_sb_block = sb_block;
3127         if (sb->s_bdev->bd_part)
3128                 sbi->s_sectors_written_start =
3129                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3130
3131         /* Cleanup superblock name */
3132         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3133                 *cp = '!';
3134
3135         ret = -EINVAL;
3136         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3137         if (!blocksize) {
3138                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3139                 goto out_fail;
3140         }
3141
3142         /*
3143          * The ext4 superblock will not be buffer aligned for other than 1kB
3144          * block sizes.  We need to calculate the offset from buffer start.
3145          */
3146         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3147                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3148                 offset = do_div(logical_sb_block, blocksize);
3149         } else {
3150                 logical_sb_block = sb_block;
3151         }
3152
3153         if (!(bh = sb_bread(sb, logical_sb_block))) {
3154                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3155                 goto out_fail;
3156         }
3157         /*
3158          * Note: s_es must be initialized as soon as possible because
3159          *       some ext4 macro-instructions depend on its value
3160          */
3161         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3162         sbi->s_es = es;
3163         sb->s_magic = le16_to_cpu(es->s_magic);
3164         if (sb->s_magic != EXT4_SUPER_MAGIC)
3165                 goto cantfind_ext4;
3166         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3167
3168         /* Set defaults before we parse the mount options */
3169         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3170         set_opt(sb, INIT_INODE_TABLE);
3171         if (def_mount_opts & EXT4_DEFM_DEBUG)
3172                 set_opt(sb, DEBUG);
3173         if (def_mount_opts & EXT4_DEFM_BSDGROUPS) {
3174                 ext4_msg(sb, KERN_WARNING, deprecated_msg, "bsdgroups",
3175                         "2.6.38");
3176                 set_opt(sb, GRPID);