Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git...
[sfrench/cifs-2.6.git] / fs / ext4 / super.c
1 /*
2  *  linux/fs/ext4/super.c
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/fs/minix/inode.c
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  *
15  *  Big-endian to little-endian byte-swapping/bitmaps by
16  *        David S. Miller (davem@caip.rutgers.edu), 1995
17  */
18
19 #include <linux/module.h>
20 #include <linux/string.h>
21 #include <linux/fs.h>
22 #include <linux/time.h>
23 #include <linux/vmalloc.h>
24 #include <linux/slab.h>
25 #include <linux/init.h>
26 #include <linux/blkdev.h>
27 #include <linux/backing-dev.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/ctype.h>
38 #include <linux/log2.h>
39 #include <linux/crc16.h>
40 #include <linux/cleancache.h>
41 #include <asm/uaccess.h>
42
43 #include <linux/kthread.h>
44 #include <linux/freezer.h>
45
46 #include "ext4.h"
47 #include "ext4_extents.h"       /* Needed for trace points definition */
48 #include "ext4_jbd2.h"
49 #include "xattr.h"
50 #include "acl.h"
51 #include "mballoc.h"
52
53 #define CREATE_TRACE_POINTS
54 #include <trace/events/ext4.h>
55
56 static struct ext4_lazy_init *ext4_li_info;
57 static struct mutex ext4_li_mtx;
58 static struct ratelimit_state ext4_mount_msg_ratelimit;
59
60 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
61                              unsigned long journal_devnum);
62 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
63 static int ext4_commit_super(struct super_block *sb, int sync);
64 static void ext4_mark_recovery_complete(struct super_block *sb,
65                                         struct ext4_super_block *es);
66 static void ext4_clear_journal_err(struct super_block *sb,
67                                    struct ext4_super_block *es);
68 static int ext4_sync_fs(struct super_block *sb, int wait);
69 static int ext4_remount(struct super_block *sb, int *flags, char *data);
70 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
71 static int ext4_unfreeze(struct super_block *sb);
72 static int ext4_freeze(struct super_block *sb);
73 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
74                        const char *dev_name, void *data);
75 static inline int ext2_feature_set_ok(struct super_block *sb);
76 static inline int ext3_feature_set_ok(struct super_block *sb);
77 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
78 static void ext4_destroy_lazyinit_thread(void);
79 static void ext4_unregister_li_request(struct super_block *sb);
80 static void ext4_clear_request_list(void);
81
82 /*
83  * Lock ordering
84  *
85  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
86  * i_mmap_rwsem (inode->i_mmap_rwsem)!
87  *
88  * page fault path:
89  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
90  *   page lock -> i_data_sem (rw)
91  *
92  * buffered write path:
93  * sb_start_write -> i_mutex -> mmap_sem
94  * sb_start_write -> i_mutex -> transaction start -> page lock ->
95  *   i_data_sem (rw)
96  *
97  * truncate:
98  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) ->
99  *   i_mmap_rwsem (w) -> page lock
100  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) ->
101  *   transaction start -> i_data_sem (rw)
102  *
103  * direct IO:
104  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) -> mmap_sem
105  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) ->
106  *   transaction start -> i_data_sem (rw)
107  *
108  * writepages:
109  * transaction start -> page lock(s) -> i_data_sem (rw)
110  */
111
112 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
113 static struct file_system_type ext2_fs_type = {
114         .owner          = THIS_MODULE,
115         .name           = "ext2",
116         .mount          = ext4_mount,
117         .kill_sb        = kill_block_super,
118         .fs_flags       = FS_REQUIRES_DEV,
119 };
120 MODULE_ALIAS_FS("ext2");
121 MODULE_ALIAS("ext2");
122 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
123 #else
124 #define IS_EXT2_SB(sb) (0)
125 #endif
126
127
128 static struct file_system_type ext3_fs_type = {
129         .owner          = THIS_MODULE,
130         .name           = "ext3",
131         .mount          = ext4_mount,
132         .kill_sb        = kill_block_super,
133         .fs_flags       = FS_REQUIRES_DEV,
134 };
135 MODULE_ALIAS_FS("ext3");
136 MODULE_ALIAS("ext3");
137 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
138
139 static int ext4_verify_csum_type(struct super_block *sb,
140                                  struct ext4_super_block *es)
141 {
142         if (!ext4_has_feature_metadata_csum(sb))
143                 return 1;
144
145         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
146 }
147
148 static __le32 ext4_superblock_csum(struct super_block *sb,
149                                    struct ext4_super_block *es)
150 {
151         struct ext4_sb_info *sbi = EXT4_SB(sb);
152         int offset = offsetof(struct ext4_super_block, s_checksum);
153         __u32 csum;
154
155         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
156
157         return cpu_to_le32(csum);
158 }
159
160 static int ext4_superblock_csum_verify(struct super_block *sb,
161                                        struct ext4_super_block *es)
162 {
163         if (!ext4_has_metadata_csum(sb))
164                 return 1;
165
166         return es->s_checksum == ext4_superblock_csum(sb, es);
167 }
168
169 void ext4_superblock_csum_set(struct super_block *sb)
170 {
171         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
172
173         if (!ext4_has_metadata_csum(sb))
174                 return;
175
176         es->s_checksum = ext4_superblock_csum(sb, es);
177 }
178
179 void *ext4_kvmalloc(size_t size, gfp_t flags)
180 {
181         void *ret;
182
183         ret = kmalloc(size, flags | __GFP_NOWARN);
184         if (!ret)
185                 ret = __vmalloc(size, flags, PAGE_KERNEL);
186         return ret;
187 }
188
189 void *ext4_kvzalloc(size_t size, gfp_t flags)
190 {
191         void *ret;
192
193         ret = kzalloc(size, flags | __GFP_NOWARN);
194         if (!ret)
195                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
196         return ret;
197 }
198
199 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
200                                struct ext4_group_desc *bg)
201 {
202         return le32_to_cpu(bg->bg_block_bitmap_lo) |
203                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
204                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
205 }
206
207 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
208                                struct ext4_group_desc *bg)
209 {
210         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
211                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
212                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
213 }
214
215 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
216                               struct ext4_group_desc *bg)
217 {
218         return le32_to_cpu(bg->bg_inode_table_lo) |
219                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
220                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
221 }
222
223 __u32 ext4_free_group_clusters(struct super_block *sb,
224                                struct ext4_group_desc *bg)
225 {
226         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
227                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
228                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
229 }
230
231 __u32 ext4_free_inodes_count(struct super_block *sb,
232                               struct ext4_group_desc *bg)
233 {
234         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
235                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
236                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
237 }
238
239 __u32 ext4_used_dirs_count(struct super_block *sb,
240                               struct ext4_group_desc *bg)
241 {
242         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
243                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
244                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
245 }
246
247 __u32 ext4_itable_unused_count(struct super_block *sb,
248                               struct ext4_group_desc *bg)
249 {
250         return le16_to_cpu(bg->bg_itable_unused_lo) |
251                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
252                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
253 }
254
255 void ext4_block_bitmap_set(struct super_block *sb,
256                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
257 {
258         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
259         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
260                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
261 }
262
263 void ext4_inode_bitmap_set(struct super_block *sb,
264                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
265 {
266         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
267         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
268                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
269 }
270
271 void ext4_inode_table_set(struct super_block *sb,
272                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
273 {
274         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
275         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
276                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
277 }
278
279 void ext4_free_group_clusters_set(struct super_block *sb,
280                                   struct ext4_group_desc *bg, __u32 count)
281 {
282         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
283         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
284                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
285 }
286
287 void ext4_free_inodes_set(struct super_block *sb,
288                           struct ext4_group_desc *bg, __u32 count)
289 {
290         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
291         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
292                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
293 }
294
295 void ext4_used_dirs_set(struct super_block *sb,
296                           struct ext4_group_desc *bg, __u32 count)
297 {
298         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
299         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
300                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
301 }
302
303 void ext4_itable_unused_set(struct super_block *sb,
304                           struct ext4_group_desc *bg, __u32 count)
305 {
306         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
307         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
308                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
309 }
310
311
312 static void __save_error_info(struct super_block *sb, const char *func,
313                             unsigned int line)
314 {
315         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
316
317         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
318         if (bdev_read_only(sb->s_bdev))
319                 return;
320         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
321         es->s_last_error_time = cpu_to_le32(get_seconds());
322         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
323         es->s_last_error_line = cpu_to_le32(line);
324         if (!es->s_first_error_time) {
325                 es->s_first_error_time = es->s_last_error_time;
326                 strncpy(es->s_first_error_func, func,
327                         sizeof(es->s_first_error_func));
328                 es->s_first_error_line = cpu_to_le32(line);
329                 es->s_first_error_ino = es->s_last_error_ino;
330                 es->s_first_error_block = es->s_last_error_block;
331         }
332         /*
333          * Start the daily error reporting function if it hasn't been
334          * started already
335          */
336         if (!es->s_error_count)
337                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
338         le32_add_cpu(&es->s_error_count, 1);
339 }
340
341 static void save_error_info(struct super_block *sb, const char *func,
342                             unsigned int line)
343 {
344         __save_error_info(sb, func, line);
345         ext4_commit_super(sb, 1);
346 }
347
348 /*
349  * The del_gendisk() function uninitializes the disk-specific data
350  * structures, including the bdi structure, without telling anyone
351  * else.  Once this happens, any attempt to call mark_buffer_dirty()
352  * (for example, by ext4_commit_super), will cause a kernel OOPS.
353  * This is a kludge to prevent these oops until we can put in a proper
354  * hook in del_gendisk() to inform the VFS and file system layers.
355  */
356 static int block_device_ejected(struct super_block *sb)
357 {
358         struct inode *bd_inode = sb->s_bdev->bd_inode;
359         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
360
361         return bdi->dev == NULL;
362 }
363
364 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
365 {
366         struct super_block              *sb = journal->j_private;
367         struct ext4_sb_info             *sbi = EXT4_SB(sb);
368         int                             error = is_journal_aborted(journal);
369         struct ext4_journal_cb_entry    *jce;
370
371         BUG_ON(txn->t_state == T_FINISHED);
372         spin_lock(&sbi->s_md_lock);
373         while (!list_empty(&txn->t_private_list)) {
374                 jce = list_entry(txn->t_private_list.next,
375                                  struct ext4_journal_cb_entry, jce_list);
376                 list_del_init(&jce->jce_list);
377                 spin_unlock(&sbi->s_md_lock);
378                 jce->jce_func(sb, jce, error);
379                 spin_lock(&sbi->s_md_lock);
380         }
381         spin_unlock(&sbi->s_md_lock);
382 }
383
384 /* Deal with the reporting of failure conditions on a filesystem such as
385  * inconsistencies detected or read IO failures.
386  *
387  * On ext2, we can store the error state of the filesystem in the
388  * superblock.  That is not possible on ext4, because we may have other
389  * write ordering constraints on the superblock which prevent us from
390  * writing it out straight away; and given that the journal is about to
391  * be aborted, we can't rely on the current, or future, transactions to
392  * write out the superblock safely.
393  *
394  * We'll just use the jbd2_journal_abort() error code to record an error in
395  * the journal instead.  On recovery, the journal will complain about
396  * that error until we've noted it down and cleared it.
397  */
398
399 static void ext4_handle_error(struct super_block *sb)
400 {
401         if (sb->s_flags & MS_RDONLY)
402                 return;
403
404         if (!test_opt(sb, ERRORS_CONT)) {
405                 journal_t *journal = EXT4_SB(sb)->s_journal;
406
407                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
408                 if (journal)
409                         jbd2_journal_abort(journal, -EIO);
410         }
411         if (test_opt(sb, ERRORS_RO)) {
412                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
413                 /*
414                  * Make sure updated value of ->s_mount_flags will be visible
415                  * before ->s_flags update
416                  */
417                 smp_wmb();
418                 sb->s_flags |= MS_RDONLY;
419         }
420         if (test_opt(sb, ERRORS_PANIC)) {
421                 if (EXT4_SB(sb)->s_journal &&
422                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
423                         return;
424                 panic("EXT4-fs (device %s): panic forced after error\n",
425                         sb->s_id);
426         }
427 }
428
429 #define ext4_error_ratelimit(sb)                                        \
430                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
431                              "EXT4-fs error")
432
433 void __ext4_error(struct super_block *sb, const char *function,
434                   unsigned int line, const char *fmt, ...)
435 {
436         struct va_format vaf;
437         va_list args;
438
439         if (ext4_error_ratelimit(sb)) {
440                 va_start(args, fmt);
441                 vaf.fmt = fmt;
442                 vaf.va = &args;
443                 printk(KERN_CRIT
444                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
445                        sb->s_id, function, line, current->comm, &vaf);
446                 va_end(args);
447         }
448         save_error_info(sb, function, line);
449         ext4_handle_error(sb);
450 }
451
452 void __ext4_error_inode(struct inode *inode, const char *function,
453                         unsigned int line, ext4_fsblk_t block,
454                         const char *fmt, ...)
455 {
456         va_list args;
457         struct va_format vaf;
458         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
459
460         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
461         es->s_last_error_block = cpu_to_le64(block);
462         if (ext4_error_ratelimit(inode->i_sb)) {
463                 va_start(args, fmt);
464                 vaf.fmt = fmt;
465                 vaf.va = &args;
466                 if (block)
467                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
468                                "inode #%lu: block %llu: comm %s: %pV\n",
469                                inode->i_sb->s_id, function, line, inode->i_ino,
470                                block, current->comm, &vaf);
471                 else
472                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
473                                "inode #%lu: comm %s: %pV\n",
474                                inode->i_sb->s_id, function, line, inode->i_ino,
475                                current->comm, &vaf);
476                 va_end(args);
477         }
478         save_error_info(inode->i_sb, function, line);
479         ext4_handle_error(inode->i_sb);
480 }
481
482 void __ext4_error_file(struct file *file, const char *function,
483                        unsigned int line, ext4_fsblk_t block,
484                        const char *fmt, ...)
485 {
486         va_list args;
487         struct va_format vaf;
488         struct ext4_super_block *es;
489         struct inode *inode = file_inode(file);
490         char pathname[80], *path;
491
492         es = EXT4_SB(inode->i_sb)->s_es;
493         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
494         if (ext4_error_ratelimit(inode->i_sb)) {
495                 path = file_path(file, pathname, sizeof(pathname));
496                 if (IS_ERR(path))
497                         path = "(unknown)";
498                 va_start(args, fmt);
499                 vaf.fmt = fmt;
500                 vaf.va = &args;
501                 if (block)
502                         printk(KERN_CRIT
503                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
504                                "block %llu: comm %s: path %s: %pV\n",
505                                inode->i_sb->s_id, function, line, inode->i_ino,
506                                block, current->comm, path, &vaf);
507                 else
508                         printk(KERN_CRIT
509                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
510                                "comm %s: path %s: %pV\n",
511                                inode->i_sb->s_id, function, line, inode->i_ino,
512                                current->comm, path, &vaf);
513                 va_end(args);
514         }
515         save_error_info(inode->i_sb, function, line);
516         ext4_handle_error(inode->i_sb);
517 }
518
519 const char *ext4_decode_error(struct super_block *sb, int errno,
520                               char nbuf[16])
521 {
522         char *errstr = NULL;
523
524         switch (errno) {
525         case -EFSCORRUPTED:
526                 errstr = "Corrupt filesystem";
527                 break;
528         case -EFSBADCRC:
529                 errstr = "Filesystem failed CRC";
530                 break;
531         case -EIO:
532                 errstr = "IO failure";
533                 break;
534         case -ENOMEM:
535                 errstr = "Out of memory";
536                 break;
537         case -EROFS:
538                 if (!sb || (EXT4_SB(sb)->s_journal &&
539                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
540                         errstr = "Journal has aborted";
541                 else
542                         errstr = "Readonly filesystem";
543                 break;
544         default:
545                 /* If the caller passed in an extra buffer for unknown
546                  * errors, textualise them now.  Else we just return
547                  * NULL. */
548                 if (nbuf) {
549                         /* Check for truncated error codes... */
550                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
551                                 errstr = nbuf;
552                 }
553                 break;
554         }
555
556         return errstr;
557 }
558
559 /* __ext4_std_error decodes expected errors from journaling functions
560  * automatically and invokes the appropriate error response.  */
561
562 void __ext4_std_error(struct super_block *sb, const char *function,
563                       unsigned int line, int errno)
564 {
565         char nbuf[16];
566         const char *errstr;
567
568         /* Special case: if the error is EROFS, and we're not already
569          * inside a transaction, then there's really no point in logging
570          * an error. */
571         if (errno == -EROFS && journal_current_handle() == NULL &&
572             (sb->s_flags & MS_RDONLY))
573                 return;
574
575         if (ext4_error_ratelimit(sb)) {
576                 errstr = ext4_decode_error(sb, errno, nbuf);
577                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
578                        sb->s_id, function, line, errstr);
579         }
580
581         save_error_info(sb, function, line);
582         ext4_handle_error(sb);
583 }
584
585 /*
586  * ext4_abort is a much stronger failure handler than ext4_error.  The
587  * abort function may be used to deal with unrecoverable failures such
588  * as journal IO errors or ENOMEM at a critical moment in log management.
589  *
590  * We unconditionally force the filesystem into an ABORT|READONLY state,
591  * unless the error response on the fs has been set to panic in which
592  * case we take the easy way out and panic immediately.
593  */
594
595 void __ext4_abort(struct super_block *sb, const char *function,
596                 unsigned int line, const char *fmt, ...)
597 {
598         va_list args;
599
600         save_error_info(sb, function, line);
601         va_start(args, fmt);
602         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
603                function, line);
604         vprintk(fmt, args);
605         printk("\n");
606         va_end(args);
607
608         if ((sb->s_flags & MS_RDONLY) == 0) {
609                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
610                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
611                 /*
612                  * Make sure updated value of ->s_mount_flags will be visible
613                  * before ->s_flags update
614                  */
615                 smp_wmb();
616                 sb->s_flags |= MS_RDONLY;
617                 if (EXT4_SB(sb)->s_journal)
618                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
619                 save_error_info(sb, function, line);
620         }
621         if (test_opt(sb, ERRORS_PANIC)) {
622                 if (EXT4_SB(sb)->s_journal &&
623                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
624                         return;
625                 panic("EXT4-fs panic from previous error\n");
626         }
627 }
628
629 void __ext4_msg(struct super_block *sb,
630                 const char *prefix, const char *fmt, ...)
631 {
632         struct va_format vaf;
633         va_list args;
634
635         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
636                 return;
637
638         va_start(args, fmt);
639         vaf.fmt = fmt;
640         vaf.va = &args;
641         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
642         va_end(args);
643 }
644
645 #define ext4_warning_ratelimit(sb)                                      \
646                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
647                              "EXT4-fs warning")
648
649 void __ext4_warning(struct super_block *sb, const char *function,
650                     unsigned int line, const char *fmt, ...)
651 {
652         struct va_format vaf;
653         va_list args;
654
655         if (!ext4_warning_ratelimit(sb))
656                 return;
657
658         va_start(args, fmt);
659         vaf.fmt = fmt;
660         vaf.va = &args;
661         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
662                sb->s_id, function, line, &vaf);
663         va_end(args);
664 }
665
666 void __ext4_warning_inode(const struct inode *inode, const char *function,
667                           unsigned int line, const char *fmt, ...)
668 {
669         struct va_format vaf;
670         va_list args;
671
672         if (!ext4_warning_ratelimit(inode->i_sb))
673                 return;
674
675         va_start(args, fmt);
676         vaf.fmt = fmt;
677         vaf.va = &args;
678         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
679                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
680                function, line, inode->i_ino, current->comm, &vaf);
681         va_end(args);
682 }
683
684 void __ext4_grp_locked_error(const char *function, unsigned int line,
685                              struct super_block *sb, ext4_group_t grp,
686                              unsigned long ino, ext4_fsblk_t block,
687                              const char *fmt, ...)
688 __releases(bitlock)
689 __acquires(bitlock)
690 {
691         struct va_format vaf;
692         va_list args;
693         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
694
695         es->s_last_error_ino = cpu_to_le32(ino);
696         es->s_last_error_block = cpu_to_le64(block);
697         __save_error_info(sb, function, line);
698
699         if (ext4_error_ratelimit(sb)) {
700                 va_start(args, fmt);
701                 vaf.fmt = fmt;
702                 vaf.va = &args;
703                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
704                        sb->s_id, function, line, grp);
705                 if (ino)
706                         printk(KERN_CONT "inode %lu: ", ino);
707                 if (block)
708                         printk(KERN_CONT "block %llu:",
709                                (unsigned long long) block);
710                 printk(KERN_CONT "%pV\n", &vaf);
711                 va_end(args);
712         }
713
714         if (test_opt(sb, ERRORS_CONT)) {
715                 ext4_commit_super(sb, 0);
716                 return;
717         }
718
719         ext4_unlock_group(sb, grp);
720         ext4_handle_error(sb);
721         /*
722          * We only get here in the ERRORS_RO case; relocking the group
723          * may be dangerous, but nothing bad will happen since the
724          * filesystem will have already been marked read/only and the
725          * journal has been aborted.  We return 1 as a hint to callers
726          * who might what to use the return value from
727          * ext4_grp_locked_error() to distinguish between the
728          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
729          * aggressively from the ext4 function in question, with a
730          * more appropriate error code.
731          */
732         ext4_lock_group(sb, grp);
733         return;
734 }
735
736 void ext4_update_dynamic_rev(struct super_block *sb)
737 {
738         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
739
740         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
741                 return;
742
743         ext4_warning(sb,
744                      "updating to rev %d because of new feature flag, "
745                      "running e2fsck is recommended",
746                      EXT4_DYNAMIC_REV);
747
748         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
749         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
750         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
751         /* leave es->s_feature_*compat flags alone */
752         /* es->s_uuid will be set by e2fsck if empty */
753
754         /*
755          * The rest of the superblock fields should be zero, and if not it
756          * means they are likely already in use, so leave them alone.  We
757          * can leave it up to e2fsck to clean up any inconsistencies there.
758          */
759 }
760
761 /*
762  * Open the external journal device
763  */
764 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
765 {
766         struct block_device *bdev;
767         char b[BDEVNAME_SIZE];
768
769         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
770         if (IS_ERR(bdev))
771                 goto fail;
772         return bdev;
773
774 fail:
775         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
776                         __bdevname(dev, b), PTR_ERR(bdev));
777         return NULL;
778 }
779
780 /*
781  * Release the journal device
782  */
783 static void ext4_blkdev_put(struct block_device *bdev)
784 {
785         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
786 }
787
788 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
789 {
790         struct block_device *bdev;
791         bdev = sbi->journal_bdev;
792         if (bdev) {
793                 ext4_blkdev_put(bdev);
794                 sbi->journal_bdev = NULL;
795         }
796 }
797
798 static inline struct inode *orphan_list_entry(struct list_head *l)
799 {
800         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
801 }
802
803 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
804 {
805         struct list_head *l;
806
807         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
808                  le32_to_cpu(sbi->s_es->s_last_orphan));
809
810         printk(KERN_ERR "sb_info orphan list:\n");
811         list_for_each(l, &sbi->s_orphan) {
812                 struct inode *inode = orphan_list_entry(l);
813                 printk(KERN_ERR "  "
814                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
815                        inode->i_sb->s_id, inode->i_ino, inode,
816                        inode->i_mode, inode->i_nlink,
817                        NEXT_ORPHAN(inode));
818         }
819 }
820
821 static void ext4_put_super(struct super_block *sb)
822 {
823         struct ext4_sb_info *sbi = EXT4_SB(sb);
824         struct ext4_super_block *es = sbi->s_es;
825         int i, err;
826
827         ext4_unregister_li_request(sb);
828         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
829
830         flush_workqueue(sbi->rsv_conversion_wq);
831         destroy_workqueue(sbi->rsv_conversion_wq);
832
833         if (sbi->s_journal) {
834                 err = jbd2_journal_destroy(sbi->s_journal);
835                 sbi->s_journal = NULL;
836                 if (err < 0)
837                         ext4_abort(sb, "Couldn't clean up the journal");
838         }
839
840         ext4_unregister_sysfs(sb);
841         ext4_es_unregister_shrinker(sbi);
842         del_timer_sync(&sbi->s_err_report);
843         ext4_release_system_zone(sb);
844         ext4_mb_release(sb);
845         ext4_ext_release(sb);
846
847         if (!(sb->s_flags & MS_RDONLY)) {
848                 ext4_clear_feature_journal_needs_recovery(sb);
849                 es->s_state = cpu_to_le16(sbi->s_mount_state);
850         }
851         if (!(sb->s_flags & MS_RDONLY))
852                 ext4_commit_super(sb, 1);
853
854         for (i = 0; i < sbi->s_gdb_count; i++)
855                 brelse(sbi->s_group_desc[i]);
856         kvfree(sbi->s_group_desc);
857         kvfree(sbi->s_flex_groups);
858         percpu_counter_destroy(&sbi->s_freeclusters_counter);
859         percpu_counter_destroy(&sbi->s_freeinodes_counter);
860         percpu_counter_destroy(&sbi->s_dirs_counter);
861         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
862         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
863         brelse(sbi->s_sbh);
864 #ifdef CONFIG_QUOTA
865         for (i = 0; i < EXT4_MAXQUOTAS; i++)
866                 kfree(sbi->s_qf_names[i]);
867 #endif
868
869         /* Debugging code just in case the in-memory inode orphan list
870          * isn't empty.  The on-disk one can be non-empty if we've
871          * detected an error and taken the fs readonly, but the
872          * in-memory list had better be clean by this point. */
873         if (!list_empty(&sbi->s_orphan))
874                 dump_orphan_list(sb, sbi);
875         J_ASSERT(list_empty(&sbi->s_orphan));
876
877         sync_blockdev(sb->s_bdev);
878         invalidate_bdev(sb->s_bdev);
879         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
880                 /*
881                  * Invalidate the journal device's buffers.  We don't want them
882                  * floating about in memory - the physical journal device may
883                  * hotswapped, and it breaks the `ro-after' testing code.
884                  */
885                 sync_blockdev(sbi->journal_bdev);
886                 invalidate_bdev(sbi->journal_bdev);
887                 ext4_blkdev_remove(sbi);
888         }
889         if (sbi->s_mb_cache) {
890                 ext4_xattr_destroy_cache(sbi->s_mb_cache);
891                 sbi->s_mb_cache = NULL;
892         }
893         if (sbi->s_mmp_tsk)
894                 kthread_stop(sbi->s_mmp_tsk);
895         sb->s_fs_info = NULL;
896         /*
897          * Now that we are completely done shutting down the
898          * superblock, we need to actually destroy the kobject.
899          */
900         kobject_put(&sbi->s_kobj);
901         wait_for_completion(&sbi->s_kobj_unregister);
902         if (sbi->s_chksum_driver)
903                 crypto_free_shash(sbi->s_chksum_driver);
904         kfree(sbi->s_blockgroup_lock);
905         kfree(sbi);
906 }
907
908 static struct kmem_cache *ext4_inode_cachep;
909
910 /*
911  * Called inside transaction, so use GFP_NOFS
912  */
913 static struct inode *ext4_alloc_inode(struct super_block *sb)
914 {
915         struct ext4_inode_info *ei;
916
917         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
918         if (!ei)
919                 return NULL;
920
921         ei->vfs_inode.i_version = 1;
922         spin_lock_init(&ei->i_raw_lock);
923         INIT_LIST_HEAD(&ei->i_prealloc_list);
924         spin_lock_init(&ei->i_prealloc_lock);
925         ext4_es_init_tree(&ei->i_es_tree);
926         rwlock_init(&ei->i_es_lock);
927         INIT_LIST_HEAD(&ei->i_es_list);
928         ei->i_es_all_nr = 0;
929         ei->i_es_shk_nr = 0;
930         ei->i_es_shrink_lblk = 0;
931         ei->i_reserved_data_blocks = 0;
932         ei->i_reserved_meta_blocks = 0;
933         ei->i_allocated_meta_blocks = 0;
934         ei->i_da_metadata_calc_len = 0;
935         ei->i_da_metadata_calc_last_lblock = 0;
936         spin_lock_init(&(ei->i_block_reservation_lock));
937 #ifdef CONFIG_QUOTA
938         ei->i_reserved_quota = 0;
939         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
940 #endif
941         ei->jinode = NULL;
942         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
943         spin_lock_init(&ei->i_completed_io_lock);
944         ei->i_sync_tid = 0;
945         ei->i_datasync_tid = 0;
946         atomic_set(&ei->i_unwritten, 0);
947         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
948         return &ei->vfs_inode;
949 }
950
951 static int ext4_drop_inode(struct inode *inode)
952 {
953         int drop = generic_drop_inode(inode);
954
955         trace_ext4_drop_inode(inode, drop);
956         return drop;
957 }
958
959 static void ext4_i_callback(struct rcu_head *head)
960 {
961         struct inode *inode = container_of(head, struct inode, i_rcu);
962         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
963 }
964
965 static void ext4_destroy_inode(struct inode *inode)
966 {
967         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
968                 ext4_msg(inode->i_sb, KERN_ERR,
969                          "Inode %lu (%p): orphan list check failed!",
970                          inode->i_ino, EXT4_I(inode));
971                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
972                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
973                                 true);
974                 dump_stack();
975         }
976         call_rcu(&inode->i_rcu, ext4_i_callback);
977 }
978
979 static void init_once(void *foo)
980 {
981         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
982
983         INIT_LIST_HEAD(&ei->i_orphan);
984         init_rwsem(&ei->xattr_sem);
985         init_rwsem(&ei->i_data_sem);
986         init_rwsem(&ei->i_mmap_sem);
987         inode_init_once(&ei->vfs_inode);
988 }
989
990 static int __init init_inodecache(void)
991 {
992         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
993                                              sizeof(struct ext4_inode_info),
994                                              0, (SLAB_RECLAIM_ACCOUNT|
995                                                 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
996                                              init_once);
997         if (ext4_inode_cachep == NULL)
998                 return -ENOMEM;
999         return 0;
1000 }
1001
1002 static void destroy_inodecache(void)
1003 {
1004         /*
1005          * Make sure all delayed rcu free inodes are flushed before we
1006          * destroy cache.
1007          */
1008         rcu_barrier();
1009         kmem_cache_destroy(ext4_inode_cachep);
1010 }
1011
1012 void ext4_clear_inode(struct inode *inode)
1013 {
1014         invalidate_inode_buffers(inode);
1015         clear_inode(inode);
1016         dquot_drop(inode);
1017         ext4_discard_preallocations(inode);
1018         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1019         if (EXT4_I(inode)->jinode) {
1020                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1021                                                EXT4_I(inode)->jinode);
1022                 jbd2_free_inode(EXT4_I(inode)->jinode);
1023                 EXT4_I(inode)->jinode = NULL;
1024         }
1025 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1026         fscrypt_put_encryption_info(inode, NULL);
1027 #endif
1028 }
1029
1030 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1031                                         u64 ino, u32 generation)
1032 {
1033         struct inode *inode;
1034
1035         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1036                 return ERR_PTR(-ESTALE);
1037         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1038                 return ERR_PTR(-ESTALE);
1039
1040         /* iget isn't really right if the inode is currently unallocated!!
1041          *
1042          * ext4_read_inode will return a bad_inode if the inode had been
1043          * deleted, so we should be safe.
1044          *
1045          * Currently we don't know the generation for parent directory, so
1046          * a generation of 0 means "accept any"
1047          */
1048         inode = ext4_iget_normal(sb, ino);
1049         if (IS_ERR(inode))
1050                 return ERR_CAST(inode);
1051         if (generation && inode->i_generation != generation) {
1052                 iput(inode);
1053                 return ERR_PTR(-ESTALE);
1054         }
1055
1056         return inode;
1057 }
1058
1059 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1060                                         int fh_len, int fh_type)
1061 {
1062         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1063                                     ext4_nfs_get_inode);
1064 }
1065
1066 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1067                                         int fh_len, int fh_type)
1068 {
1069         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1070                                     ext4_nfs_get_inode);
1071 }
1072
1073 /*
1074  * Try to release metadata pages (indirect blocks, directories) which are
1075  * mapped via the block device.  Since these pages could have journal heads
1076  * which would prevent try_to_free_buffers() from freeing them, we must use
1077  * jbd2 layer's try_to_free_buffers() function to release them.
1078  */
1079 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1080                                  gfp_t wait)
1081 {
1082         journal_t *journal = EXT4_SB(sb)->s_journal;
1083
1084         WARN_ON(PageChecked(page));
1085         if (!page_has_buffers(page))
1086                 return 0;
1087         if (journal)
1088                 return jbd2_journal_try_to_free_buffers(journal, page,
1089                                                 wait & ~__GFP_DIRECT_RECLAIM);
1090         return try_to_free_buffers(page);
1091 }
1092
1093 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1094 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1095 {
1096         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1097                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1098 }
1099
1100 static int ext4_key_prefix(struct inode *inode, u8 **key)
1101 {
1102         *key = EXT4_SB(inode->i_sb)->key_prefix;
1103         return EXT4_SB(inode->i_sb)->key_prefix_size;
1104 }
1105
1106 static int ext4_prepare_context(struct inode *inode)
1107 {
1108         return ext4_convert_inline_data(inode);
1109 }
1110
1111 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1112                                                         void *fs_data)
1113 {
1114         handle_t *handle;
1115         int res, res2;
1116
1117         /* fs_data is null when internally used. */
1118         if (fs_data) {
1119                 res  = ext4_xattr_set(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1120                                 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx,
1121                                 len, 0);
1122                 if (!res) {
1123                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1124                         ext4_clear_inode_state(inode,
1125                                         EXT4_STATE_MAY_INLINE_DATA);
1126                 }
1127                 return res;
1128         }
1129
1130         handle = ext4_journal_start(inode, EXT4_HT_MISC,
1131                         ext4_jbd2_credits_xattr(inode));
1132         if (IS_ERR(handle))
1133                 return PTR_ERR(handle);
1134
1135         res = ext4_xattr_set(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1136                         EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx,
1137                         len, 0);
1138         if (!res) {
1139                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1140                 res = ext4_mark_inode_dirty(handle, inode);
1141                 if (res)
1142                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1143         }
1144         res2 = ext4_journal_stop(handle);
1145         if (!res)
1146                 res = res2;
1147         return res;
1148 }
1149
1150 static int ext4_dummy_context(struct inode *inode)
1151 {
1152         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1153 }
1154
1155 static unsigned ext4_max_namelen(struct inode *inode)
1156 {
1157         return S_ISLNK(inode->i_mode) ? inode->i_sb->s_blocksize :
1158                 EXT4_NAME_LEN;
1159 }
1160
1161 static struct fscrypt_operations ext4_cryptops = {
1162         .get_context            = ext4_get_context,
1163         .key_prefix             = ext4_key_prefix,
1164         .prepare_context        = ext4_prepare_context,
1165         .set_context            = ext4_set_context,
1166         .dummy_context          = ext4_dummy_context,
1167         .is_encrypted           = ext4_encrypted_inode,
1168         .empty_dir              = ext4_empty_dir,
1169         .max_namelen            = ext4_max_namelen,
1170 };
1171 #else
1172 static struct fscrypt_operations ext4_cryptops = {
1173         .is_encrypted           = ext4_encrypted_inode,
1174 };
1175 #endif
1176
1177 #ifdef CONFIG_QUOTA
1178 static char *quotatypes[] = INITQFNAMES;
1179 #define QTYPE2NAME(t) (quotatypes[t])
1180
1181 static int ext4_write_dquot(struct dquot *dquot);
1182 static int ext4_acquire_dquot(struct dquot *dquot);
1183 static int ext4_release_dquot(struct dquot *dquot);
1184 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1185 static int ext4_write_info(struct super_block *sb, int type);
1186 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1187                          struct path *path);
1188 static int ext4_quota_off(struct super_block *sb, int type);
1189 static int ext4_quota_on_mount(struct super_block *sb, int type);
1190 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1191                                size_t len, loff_t off);
1192 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1193                                 const char *data, size_t len, loff_t off);
1194 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1195                              unsigned int flags);
1196 static int ext4_enable_quotas(struct super_block *sb);
1197 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1198
1199 static struct dquot **ext4_get_dquots(struct inode *inode)
1200 {
1201         return EXT4_I(inode)->i_dquot;
1202 }
1203
1204 static const struct dquot_operations ext4_quota_operations = {
1205         .get_reserved_space = ext4_get_reserved_space,
1206         .write_dquot    = ext4_write_dquot,
1207         .acquire_dquot  = ext4_acquire_dquot,
1208         .release_dquot  = ext4_release_dquot,
1209         .mark_dirty     = ext4_mark_dquot_dirty,
1210         .write_info     = ext4_write_info,
1211         .alloc_dquot    = dquot_alloc,
1212         .destroy_dquot  = dquot_destroy,
1213         .get_projid     = ext4_get_projid,
1214         .get_next_id    = ext4_get_next_id,
1215 };
1216
1217 static const struct quotactl_ops ext4_qctl_operations = {
1218         .quota_on       = ext4_quota_on,
1219         .quota_off      = ext4_quota_off,
1220         .quota_sync     = dquot_quota_sync,
1221         .get_state      = dquot_get_state,
1222         .set_info       = dquot_set_dqinfo,
1223         .get_dqblk      = dquot_get_dqblk,
1224         .set_dqblk      = dquot_set_dqblk,
1225         .get_nextdqblk  = dquot_get_next_dqblk,
1226 };
1227 #endif
1228
1229 static const struct super_operations ext4_sops = {
1230         .alloc_inode    = ext4_alloc_inode,
1231         .destroy_inode  = ext4_destroy_inode,
1232         .write_inode    = ext4_write_inode,
1233         .dirty_inode    = ext4_dirty_inode,
1234         .drop_inode     = ext4_drop_inode,
1235         .evict_inode    = ext4_evict_inode,
1236         .put_super      = ext4_put_super,
1237         .sync_fs        = ext4_sync_fs,
1238         .freeze_fs      = ext4_freeze,
1239         .unfreeze_fs    = ext4_unfreeze,
1240         .statfs         = ext4_statfs,
1241         .remount_fs     = ext4_remount,
1242         .show_options   = ext4_show_options,
1243 #ifdef CONFIG_QUOTA
1244         .quota_read     = ext4_quota_read,
1245         .quota_write    = ext4_quota_write,
1246         .get_dquots     = ext4_get_dquots,
1247 #endif
1248         .bdev_try_to_free_page = bdev_try_to_free_page,
1249 };
1250
1251 static const struct export_operations ext4_export_ops = {
1252         .fh_to_dentry = ext4_fh_to_dentry,
1253         .fh_to_parent = ext4_fh_to_parent,
1254         .get_parent = ext4_get_parent,
1255 };
1256
1257 enum {
1258         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1259         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1260         Opt_nouid32, Opt_debug, Opt_removed,
1261         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1262         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1263         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1264         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1265         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1266         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1267         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1268         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1269         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1270         Opt_usrquota, Opt_grpquota, Opt_i_version, Opt_dax,
1271         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1272         Opt_lazytime, Opt_nolazytime,
1273         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1274         Opt_inode_readahead_blks, Opt_journal_ioprio,
1275         Opt_dioread_nolock, Opt_dioread_lock,
1276         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1277         Opt_max_dir_size_kb, Opt_nojournal_checksum,
1278 };
1279
1280 static const match_table_t tokens = {
1281         {Opt_bsd_df, "bsddf"},
1282         {Opt_minix_df, "minixdf"},
1283         {Opt_grpid, "grpid"},
1284         {Opt_grpid, "bsdgroups"},
1285         {Opt_nogrpid, "nogrpid"},
1286         {Opt_nogrpid, "sysvgroups"},
1287         {Opt_resgid, "resgid=%u"},
1288         {Opt_resuid, "resuid=%u"},
1289         {Opt_sb, "sb=%u"},
1290         {Opt_err_cont, "errors=continue"},
1291         {Opt_err_panic, "errors=panic"},
1292         {Opt_err_ro, "errors=remount-ro"},
1293         {Opt_nouid32, "nouid32"},
1294         {Opt_debug, "debug"},
1295         {Opt_removed, "oldalloc"},
1296         {Opt_removed, "orlov"},
1297         {Opt_user_xattr, "user_xattr"},
1298         {Opt_nouser_xattr, "nouser_xattr"},
1299         {Opt_acl, "acl"},
1300         {Opt_noacl, "noacl"},
1301         {Opt_noload, "norecovery"},
1302         {Opt_noload, "noload"},
1303         {Opt_removed, "nobh"},
1304         {Opt_removed, "bh"},
1305         {Opt_commit, "commit=%u"},
1306         {Opt_min_batch_time, "min_batch_time=%u"},
1307         {Opt_max_batch_time, "max_batch_time=%u"},
1308         {Opt_journal_dev, "journal_dev=%u"},
1309         {Opt_journal_path, "journal_path=%s"},
1310         {Opt_journal_checksum, "journal_checksum"},
1311         {Opt_nojournal_checksum, "nojournal_checksum"},
1312         {Opt_journal_async_commit, "journal_async_commit"},
1313         {Opt_abort, "abort"},
1314         {Opt_data_journal, "data=journal"},
1315         {Opt_data_ordered, "data=ordered"},
1316         {Opt_data_writeback, "data=writeback"},
1317         {Opt_data_err_abort, "data_err=abort"},
1318         {Opt_data_err_ignore, "data_err=ignore"},
1319         {Opt_offusrjquota, "usrjquota="},
1320         {Opt_usrjquota, "usrjquota=%s"},
1321         {Opt_offgrpjquota, "grpjquota="},
1322         {Opt_grpjquota, "grpjquota=%s"},
1323         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1324         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1325         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1326         {Opt_grpquota, "grpquota"},
1327         {Opt_noquota, "noquota"},
1328         {Opt_quota, "quota"},
1329         {Opt_usrquota, "usrquota"},
1330         {Opt_barrier, "barrier=%u"},
1331         {Opt_barrier, "barrier"},
1332         {Opt_nobarrier, "nobarrier"},
1333         {Opt_i_version, "i_version"},
1334         {Opt_dax, "dax"},
1335         {Opt_stripe, "stripe=%u"},
1336         {Opt_delalloc, "delalloc"},
1337         {Opt_lazytime, "lazytime"},
1338         {Opt_nolazytime, "nolazytime"},
1339         {Opt_nodelalloc, "nodelalloc"},
1340         {Opt_removed, "mblk_io_submit"},
1341         {Opt_removed, "nomblk_io_submit"},
1342         {Opt_block_validity, "block_validity"},
1343         {Opt_noblock_validity, "noblock_validity"},
1344         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1345         {Opt_journal_ioprio, "journal_ioprio=%u"},
1346         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1347         {Opt_auto_da_alloc, "auto_da_alloc"},
1348         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1349         {Opt_dioread_nolock, "dioread_nolock"},
1350         {Opt_dioread_lock, "dioread_lock"},
1351         {Opt_discard, "discard"},
1352         {Opt_nodiscard, "nodiscard"},
1353         {Opt_init_itable, "init_itable=%u"},
1354         {Opt_init_itable, "init_itable"},
1355         {Opt_noinit_itable, "noinit_itable"},
1356         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1357         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1358         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1359         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1360         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1361         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1362         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1363         {Opt_err, NULL},
1364 };
1365
1366 static ext4_fsblk_t get_sb_block(void **data)
1367 {
1368         ext4_fsblk_t    sb_block;
1369         char            *options = (char *) *data;
1370
1371         if (!options || strncmp(options, "sb=", 3) != 0)
1372                 return 1;       /* Default location */
1373
1374         options += 3;
1375         /* TODO: use simple_strtoll with >32bit ext4 */
1376         sb_block = simple_strtoul(options, &options, 0);
1377         if (*options && *options != ',') {
1378                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1379                        (char *) *data);
1380                 return 1;
1381         }
1382         if (*options == ',')
1383                 options++;
1384         *data = (void *) options;
1385
1386         return sb_block;
1387 }
1388
1389 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1390 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1391         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1392
1393 #ifdef CONFIG_QUOTA
1394 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1395 {
1396         struct ext4_sb_info *sbi = EXT4_SB(sb);
1397         char *qname;
1398         int ret = -1;
1399
1400         if (sb_any_quota_loaded(sb) &&
1401                 !sbi->s_qf_names[qtype]) {
1402                 ext4_msg(sb, KERN_ERR,
1403                         "Cannot change journaled "
1404                         "quota options when quota turned on");
1405                 return -1;
1406         }
1407         if (ext4_has_feature_quota(sb)) {
1408                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1409                          "ignored when QUOTA feature is enabled");
1410                 return 1;
1411         }
1412         qname = match_strdup(args);
1413         if (!qname) {
1414                 ext4_msg(sb, KERN_ERR,
1415                         "Not enough memory for storing quotafile name");
1416                 return -1;
1417         }
1418         if (sbi->s_qf_names[qtype]) {
1419                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1420                         ret = 1;
1421                 else
1422                         ext4_msg(sb, KERN_ERR,
1423                                  "%s quota file already specified",
1424                                  QTYPE2NAME(qtype));
1425                 goto errout;
1426         }
1427         if (strchr(qname, '/')) {
1428                 ext4_msg(sb, KERN_ERR,
1429                         "quotafile must be on filesystem root");
1430                 goto errout;
1431         }
1432         sbi->s_qf_names[qtype] = qname;
1433         set_opt(sb, QUOTA);
1434         return 1;
1435 errout:
1436         kfree(qname);
1437         return ret;
1438 }
1439
1440 static int clear_qf_name(struct super_block *sb, int qtype)
1441 {
1442
1443         struct ext4_sb_info *sbi = EXT4_SB(sb);
1444
1445         if (sb_any_quota_loaded(sb) &&
1446                 sbi->s_qf_names[qtype]) {
1447                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1448                         " when quota turned on");
1449                 return -1;
1450         }
1451         kfree(sbi->s_qf_names[qtype]);
1452         sbi->s_qf_names[qtype] = NULL;
1453         return 1;
1454 }
1455 #endif
1456
1457 #define MOPT_SET        0x0001
1458 #define MOPT_CLEAR      0x0002
1459 #define MOPT_NOSUPPORT  0x0004
1460 #define MOPT_EXPLICIT   0x0008
1461 #define MOPT_CLEAR_ERR  0x0010
1462 #define MOPT_GTE0       0x0020
1463 #ifdef CONFIG_QUOTA
1464 #define MOPT_Q          0
1465 #define MOPT_QFMT       0x0040
1466 #else
1467 #define MOPT_Q          MOPT_NOSUPPORT
1468 #define MOPT_QFMT       MOPT_NOSUPPORT
1469 #endif
1470 #define MOPT_DATAJ      0x0080
1471 #define MOPT_NO_EXT2    0x0100
1472 #define MOPT_NO_EXT3    0x0200
1473 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1474 #define MOPT_STRING     0x0400
1475
1476 static const struct mount_opts {
1477         int     token;
1478         int     mount_opt;
1479         int     flags;
1480 } ext4_mount_opts[] = {
1481         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1482         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1483         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1484         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1485         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1486         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1487         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1488          MOPT_EXT4_ONLY | MOPT_SET},
1489         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1490          MOPT_EXT4_ONLY | MOPT_CLEAR},
1491         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1492         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1493         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1494          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1495         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1496          MOPT_EXT4_ONLY | MOPT_CLEAR},
1497         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1498          MOPT_EXT4_ONLY | MOPT_CLEAR},
1499         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1500          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1501         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1502                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1503          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1504         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1505         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1506         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1507         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1508         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1509          MOPT_NO_EXT2},
1510         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1511          MOPT_NO_EXT2},
1512         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1513         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1514         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1515         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1516         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1517         {Opt_commit, 0, MOPT_GTE0},
1518         {Opt_max_batch_time, 0, MOPT_GTE0},
1519         {Opt_min_batch_time, 0, MOPT_GTE0},
1520         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1521         {Opt_init_itable, 0, MOPT_GTE0},
1522         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1523         {Opt_stripe, 0, MOPT_GTE0},
1524         {Opt_resuid, 0, MOPT_GTE0},
1525         {Opt_resgid, 0, MOPT_GTE0},
1526         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1527         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1528         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1529         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1530         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1531         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1532          MOPT_NO_EXT2 | MOPT_DATAJ},
1533         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1534         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1535 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1536         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1537         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1538 #else
1539         {Opt_acl, 0, MOPT_NOSUPPORT},
1540         {Opt_noacl, 0, MOPT_NOSUPPORT},
1541 #endif
1542         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1543         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1544         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1545         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1546                                                         MOPT_SET | MOPT_Q},
1547         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1548                                                         MOPT_SET | MOPT_Q},
1549         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1550                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1551         {Opt_usrjquota, 0, MOPT_Q},
1552         {Opt_grpjquota, 0, MOPT_Q},
1553         {Opt_offusrjquota, 0, MOPT_Q},
1554         {Opt_offgrpjquota, 0, MOPT_Q},
1555         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1556         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1557         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1558         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1559         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1560         {Opt_err, 0, 0}
1561 };
1562
1563 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1564                             substring_t *args, unsigned long *journal_devnum,
1565                             unsigned int *journal_ioprio, int is_remount)
1566 {
1567         struct ext4_sb_info *sbi = EXT4_SB(sb);
1568         const struct mount_opts *m;
1569         kuid_t uid;
1570         kgid_t gid;
1571         int arg = 0;
1572
1573 #ifdef CONFIG_QUOTA
1574         if (token == Opt_usrjquota)
1575                 return set_qf_name(sb, USRQUOTA, &args[0]);
1576         else if (token == Opt_grpjquota)
1577                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1578         else if (token == Opt_offusrjquota)
1579                 return clear_qf_name(sb, USRQUOTA);
1580         else if (token == Opt_offgrpjquota)
1581                 return clear_qf_name(sb, GRPQUOTA);
1582 #endif
1583         switch (token) {
1584         case Opt_noacl:
1585         case Opt_nouser_xattr:
1586                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1587                 break;
1588         case Opt_sb:
1589                 return 1;       /* handled by get_sb_block() */
1590         case Opt_removed:
1591                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1592                 return 1;
1593         case Opt_abort:
1594                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1595                 return 1;
1596         case Opt_i_version:
1597                 sb->s_flags |= MS_I_VERSION;
1598                 return 1;
1599         case Opt_lazytime:
1600                 sb->s_flags |= MS_LAZYTIME;
1601                 return 1;
1602         case Opt_nolazytime:
1603                 sb->s_flags &= ~MS_LAZYTIME;
1604                 return 1;
1605         }
1606
1607         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1608                 if (token == m->token)
1609                         break;
1610
1611         if (m->token == Opt_err) {
1612                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1613                          "or missing value", opt);
1614                 return -1;
1615         }
1616
1617         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1618                 ext4_msg(sb, KERN_ERR,
1619                          "Mount option \"%s\" incompatible with ext2", opt);
1620                 return -1;
1621         }
1622         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1623                 ext4_msg(sb, KERN_ERR,
1624                          "Mount option \"%s\" incompatible with ext3", opt);
1625                 return -1;
1626         }
1627
1628         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1629                 return -1;
1630         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1631                 return -1;
1632         if (m->flags & MOPT_EXPLICIT) {
1633                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1634                         set_opt2(sb, EXPLICIT_DELALLOC);
1635                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1636                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1637                 } else
1638                         return -1;
1639         }
1640         if (m->flags & MOPT_CLEAR_ERR)
1641                 clear_opt(sb, ERRORS_MASK);
1642         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1643                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1644                          "options when quota turned on");
1645                 return -1;
1646         }
1647
1648         if (m->flags & MOPT_NOSUPPORT) {
1649                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1650         } else if (token == Opt_commit) {
1651                 if (arg == 0)
1652                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1653                 sbi->s_commit_interval = HZ * arg;
1654         } else if (token == Opt_max_batch_time) {
1655                 sbi->s_max_batch_time = arg;
1656         } else if (token == Opt_min_batch_time) {
1657                 sbi->s_min_batch_time = arg;
1658         } else if (token == Opt_inode_readahead_blks) {
1659                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1660                         ext4_msg(sb, KERN_ERR,
1661                                  "EXT4-fs: inode_readahead_blks must be "
1662                                  "0 or a power of 2 smaller than 2^31");
1663                         return -1;
1664                 }
1665                 sbi->s_inode_readahead_blks = arg;
1666         } else if (token == Opt_init_itable) {
1667                 set_opt(sb, INIT_INODE_TABLE);
1668                 if (!args->from)
1669                         arg = EXT4_DEF_LI_WAIT_MULT;
1670                 sbi->s_li_wait_mult = arg;
1671         } else if (token == Opt_max_dir_size_kb) {
1672                 sbi->s_max_dir_size_kb = arg;
1673         } else if (token == Opt_stripe) {
1674                 sbi->s_stripe = arg;
1675         } else if (token == Opt_resuid) {
1676                 uid = make_kuid(current_user_ns(), arg);
1677                 if (!uid_valid(uid)) {
1678                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1679                         return -1;
1680                 }
1681                 sbi->s_resuid = uid;
1682         } else if (token == Opt_resgid) {
1683                 gid = make_kgid(current_user_ns(), arg);
1684                 if (!gid_valid(gid)) {
1685                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1686                         return -1;
1687                 }
1688                 sbi->s_resgid = gid;
1689         } else if (token == Opt_journal_dev) {
1690                 if (is_remount) {
1691                         ext4_msg(sb, KERN_ERR,
1692                                  "Cannot specify journal on remount");
1693                         return -1;
1694                 }
1695                 *journal_devnum = arg;
1696         } else if (token == Opt_journal_path) {
1697                 char *journal_path;
1698                 struct inode *journal_inode;
1699                 struct path path;
1700                 int error;
1701
1702                 if (is_remount) {
1703                         ext4_msg(sb, KERN_ERR,
1704                                  "Cannot specify journal on remount");
1705                         return -1;
1706                 }
1707                 journal_path = match_strdup(&args[0]);
1708                 if (!journal_path) {
1709                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1710                                 "journal device string");
1711                         return -1;
1712                 }
1713
1714                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1715                 if (error) {
1716                         ext4_msg(sb, KERN_ERR, "error: could not find "
1717                                 "journal device path: error %d", error);
1718                         kfree(journal_path);
1719                         return -1;
1720                 }
1721
1722                 journal_inode = d_inode(path.dentry);
1723                 if (!S_ISBLK(journal_inode->i_mode)) {
1724                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1725                                 "is not a block device", journal_path);
1726                         path_put(&path);
1727                         kfree(journal_path);
1728                         return -1;
1729                 }
1730
1731                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1732                 path_put(&path);
1733                 kfree(journal_path);
1734         } else if (token == Opt_journal_ioprio) {
1735                 if (arg > 7) {
1736                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1737                                  " (must be 0-7)");
1738                         return -1;
1739                 }
1740                 *journal_ioprio =
1741                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1742         } else if (token == Opt_test_dummy_encryption) {
1743 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1744                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1745                 ext4_msg(sb, KERN_WARNING,
1746                          "Test dummy encryption mode enabled");
1747 #else
1748                 ext4_msg(sb, KERN_WARNING,
1749                          "Test dummy encryption mount option ignored");
1750 #endif
1751         } else if (m->flags & MOPT_DATAJ) {
1752                 if (is_remount) {
1753                         if (!sbi->s_journal)
1754                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1755                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1756                                 ext4_msg(sb, KERN_ERR,
1757                                          "Cannot change data mode on remount");
1758                                 return -1;
1759                         }
1760                 } else {
1761                         clear_opt(sb, DATA_FLAGS);
1762                         sbi->s_mount_opt |= m->mount_opt;
1763                 }
1764 #ifdef CONFIG_QUOTA
1765         } else if (m->flags & MOPT_QFMT) {
1766                 if (sb_any_quota_loaded(sb) &&
1767                     sbi->s_jquota_fmt != m->mount_opt) {
1768                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1769                                  "quota options when quota turned on");
1770                         return -1;
1771                 }
1772                 if (ext4_has_feature_quota(sb)) {
1773                         ext4_msg(sb, KERN_INFO,
1774                                  "Quota format mount options ignored "
1775                                  "when QUOTA feature is enabled");
1776                         return 1;
1777                 }
1778                 sbi->s_jquota_fmt = m->mount_opt;
1779 #endif
1780         } else if (token == Opt_dax) {
1781 #ifdef CONFIG_FS_DAX
1782                 ext4_msg(sb, KERN_WARNING,
1783                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1784                         sbi->s_mount_opt |= m->mount_opt;
1785 #else
1786                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1787                 return -1;
1788 #endif
1789         } else if (token == Opt_data_err_abort) {
1790                 sbi->s_mount_opt |= m->mount_opt;
1791         } else if (token == Opt_data_err_ignore) {
1792                 sbi->s_mount_opt &= ~m->mount_opt;
1793         } else {
1794                 if (!args->from)
1795                         arg = 1;
1796                 if (m->flags & MOPT_CLEAR)
1797                         arg = !arg;
1798                 else if (unlikely(!(m->flags & MOPT_SET))) {
1799                         ext4_msg(sb, KERN_WARNING,
1800                                  "buggy handling of option %s", opt);
1801                         WARN_ON(1);
1802                         return -1;
1803                 }
1804                 if (arg != 0)
1805                         sbi->s_mount_opt |= m->mount_opt;
1806                 else
1807                         sbi->s_mount_opt &= ~m->mount_opt;
1808         }
1809         return 1;
1810 }
1811
1812 static int parse_options(char *options, struct super_block *sb,
1813                          unsigned long *journal_devnum,
1814                          unsigned int *journal_ioprio,
1815                          int is_remount)
1816 {
1817         struct ext4_sb_info *sbi = EXT4_SB(sb);
1818         char *p;
1819         substring_t args[MAX_OPT_ARGS];
1820         int token;
1821
1822         if (!options)
1823                 return 1;
1824
1825         while ((p = strsep(&options, ",")) != NULL) {
1826                 if (!*p)
1827                         continue;
1828                 /*
1829                  * Initialize args struct so we know whether arg was
1830                  * found; some options take optional arguments.
1831                  */
1832                 args[0].to = args[0].from = NULL;
1833                 token = match_token(p, tokens, args);
1834                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1835                                      journal_ioprio, is_remount) < 0)
1836                         return 0;
1837         }
1838 #ifdef CONFIG_QUOTA
1839         if (ext4_has_feature_quota(sb) &&
1840             (test_opt(sb, USRQUOTA) || test_opt(sb, GRPQUOTA))) {
1841                 ext4_msg(sb, KERN_INFO, "Quota feature enabled, usrquota and grpquota "
1842                          "mount options ignored.");
1843                 clear_opt(sb, USRQUOTA);
1844                 clear_opt(sb, GRPQUOTA);
1845         } else if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1846                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1847                         clear_opt(sb, USRQUOTA);
1848
1849                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1850                         clear_opt(sb, GRPQUOTA);
1851
1852                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1853                         ext4_msg(sb, KERN_ERR, "old and new quota "
1854                                         "format mixing");
1855                         return 0;
1856                 }
1857
1858                 if (!sbi->s_jquota_fmt) {
1859                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1860                                         "not specified");
1861                         return 0;
1862                 }
1863         }
1864 #endif
1865         if (test_opt(sb, DIOREAD_NOLOCK)) {
1866                 int blocksize =
1867                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1868
1869                 if (blocksize < PAGE_SIZE) {
1870                         ext4_msg(sb, KERN_ERR, "can't mount with "
1871                                  "dioread_nolock if block size != PAGE_SIZE");
1872                         return 0;
1873                 }
1874         }
1875         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
1876             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
1877                 ext4_msg(sb, KERN_ERR, "can't mount with journal_async_commit "
1878                          "in data=ordered mode");
1879                 return 0;
1880         }
1881         return 1;
1882 }
1883
1884 static inline void ext4_show_quota_options(struct seq_file *seq,
1885                                            struct super_block *sb)
1886 {
1887 #if defined(CONFIG_QUOTA)
1888         struct ext4_sb_info *sbi = EXT4_SB(sb);
1889
1890         if (sbi->s_jquota_fmt) {
1891                 char *fmtname = "";
1892
1893                 switch (sbi->s_jquota_fmt) {
1894                 case QFMT_VFS_OLD:
1895                         fmtname = "vfsold";
1896                         break;
1897                 case QFMT_VFS_V0:
1898                         fmtname = "vfsv0";
1899                         break;
1900                 case QFMT_VFS_V1:
1901                         fmtname = "vfsv1";
1902                         break;
1903                 }
1904                 seq_printf(seq, ",jqfmt=%s", fmtname);
1905         }
1906
1907         if (sbi->s_qf_names[USRQUOTA])
1908                 seq_show_option(seq, "usrjquota", sbi->s_qf_names[USRQUOTA]);
1909
1910         if (sbi->s_qf_names[GRPQUOTA])
1911                 seq_show_option(seq, "grpjquota", sbi->s_qf_names[GRPQUOTA]);
1912 #endif
1913 }
1914
1915 static const char *token2str(int token)
1916 {
1917         const struct match_token *t;
1918
1919         for (t = tokens; t->token != Opt_err; t++)
1920                 if (t->token == token && !strchr(t->pattern, '='))
1921                         break;
1922         return t->pattern;
1923 }
1924
1925 /*
1926  * Show an option if
1927  *  - it's set to a non-default value OR
1928  *  - if the per-sb default is different from the global default
1929  */
1930 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1931                               int nodefs)
1932 {
1933         struct ext4_sb_info *sbi = EXT4_SB(sb);
1934         struct ext4_super_block *es = sbi->s_es;
1935         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1936         const struct mount_opts *m;
1937         char sep = nodefs ? '\n' : ',';
1938
1939 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1940 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1941
1942         if (sbi->s_sb_block != 1)
1943                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1944
1945         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1946                 int want_set = m->flags & MOPT_SET;
1947                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1948                     (m->flags & MOPT_CLEAR_ERR))
1949                         continue;
1950                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1951                         continue; /* skip if same as the default */
1952                 if ((want_set &&
1953                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1954                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1955                         continue; /* select Opt_noFoo vs Opt_Foo */
1956                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1957         }
1958
1959         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1960             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1961                 SEQ_OPTS_PRINT("resuid=%u",
1962                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1963         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1964             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1965                 SEQ_OPTS_PRINT("resgid=%u",
1966                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1967         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1968         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1969                 SEQ_OPTS_PUTS("errors=remount-ro");
1970         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1971                 SEQ_OPTS_PUTS("errors=continue");
1972         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1973                 SEQ_OPTS_PUTS("errors=panic");
1974         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1975                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1976         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1977                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1978         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1979                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1980         if (sb->s_flags & MS_I_VERSION)
1981                 SEQ_OPTS_PUTS("i_version");
1982         if (nodefs || sbi->s_stripe)
1983                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1984         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1985                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1986                         SEQ_OPTS_PUTS("data=journal");
1987                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1988                         SEQ_OPTS_PUTS("data=ordered");
1989                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1990                         SEQ_OPTS_PUTS("data=writeback");
1991         }
1992         if (nodefs ||
1993             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1994                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1995                                sbi->s_inode_readahead_blks);
1996
1997         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1998                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1999                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2000         if (nodefs || sbi->s_max_dir_size_kb)
2001                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2002         if (test_opt(sb, DATA_ERR_ABORT))
2003                 SEQ_OPTS_PUTS("data_err=abort");
2004
2005         ext4_show_quota_options(seq, sb);
2006         return 0;
2007 }
2008
2009 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2010 {
2011         return _ext4_show_options(seq, root->d_sb, 0);
2012 }
2013
2014 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2015 {
2016         struct super_block *sb = seq->private;
2017         int rc;
2018
2019         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
2020         rc = _ext4_show_options(seq, sb, 1);
2021         seq_puts(seq, "\n");
2022         return rc;
2023 }
2024
2025 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2026                             int read_only)
2027 {
2028         struct ext4_sb_info *sbi = EXT4_SB(sb);
2029         int res = 0;
2030
2031         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2032                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2033                          "forcing read-only mode");
2034                 res = MS_RDONLY;
2035         }
2036         if (read_only)
2037                 goto done;
2038         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2039                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2040                          "running e2fsck is recommended");
2041         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2042                 ext4_msg(sb, KERN_WARNING,
2043                          "warning: mounting fs with errors, "
2044                          "running e2fsck is recommended");
2045         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2046                  le16_to_cpu(es->s_mnt_count) >=
2047                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2048                 ext4_msg(sb, KERN_WARNING,
2049                          "warning: maximal mount count reached, "
2050                          "running e2fsck is recommended");
2051         else if (le32_to_cpu(es->s_checkinterval) &&
2052                 (le32_to_cpu(es->s_lastcheck) +
2053                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
2054                 ext4_msg(sb, KERN_WARNING,
2055                          "warning: checktime reached, "
2056                          "running e2fsck is recommended");
2057         if (!sbi->s_journal)
2058                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2059         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2060                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2061         le16_add_cpu(&es->s_mnt_count, 1);
2062         es->s_mtime = cpu_to_le32(get_seconds());
2063         ext4_update_dynamic_rev(sb);
2064         if (sbi->s_journal)
2065                 ext4_set_feature_journal_needs_recovery(sb);
2066
2067         ext4_commit_super(sb, 1);
2068 done:
2069         if (test_opt(sb, DEBUG))
2070                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2071                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2072                         sb->s_blocksize,
2073                         sbi->s_groups_count,
2074                         EXT4_BLOCKS_PER_GROUP(sb),
2075                         EXT4_INODES_PER_GROUP(sb),
2076                         sbi->s_mount_opt, sbi->s_mount_opt2);
2077
2078         cleancache_init_fs(sb);
2079         return res;
2080 }
2081
2082 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2083 {
2084         struct ext4_sb_info *sbi = EXT4_SB(sb);
2085         struct flex_groups *new_groups;
2086         int size;
2087
2088         if (!sbi->s_log_groups_per_flex)
2089                 return 0;
2090
2091         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2092         if (size <= sbi->s_flex_groups_allocated)
2093                 return 0;
2094
2095         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2096         new_groups = ext4_kvzalloc(size, GFP_KERNEL);
2097         if (!new_groups) {
2098                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2099                          size / (int) sizeof(struct flex_groups));
2100                 return -ENOMEM;
2101         }
2102
2103         if (sbi->s_flex_groups) {
2104                 memcpy(new_groups, sbi->s_flex_groups,
2105                        (sbi->s_flex_groups_allocated *
2106                         sizeof(struct flex_groups)));
2107                 kvfree(sbi->s_flex_groups);
2108         }
2109         sbi->s_flex_groups = new_groups;
2110         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2111         return 0;
2112 }
2113
2114 static int ext4_fill_flex_info(struct super_block *sb)
2115 {
2116         struct ext4_sb_info *sbi = EXT4_SB(sb);
2117         struct ext4_group_desc *gdp = NULL;
2118         ext4_group_t flex_group;
2119         int i, err;
2120
2121         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2122         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2123                 sbi->s_log_groups_per_flex = 0;
2124                 return 1;
2125         }
2126
2127         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2128         if (err)
2129                 goto failed;
2130
2131         for (i = 0; i < sbi->s_groups_count; i++) {
2132                 gdp = ext4_get_group_desc(sb, i, NULL);
2133
2134                 flex_group = ext4_flex_group(sbi, i);
2135                 atomic_add(ext4_free_inodes_count(sb, gdp),
2136                            &sbi->s_flex_groups[flex_group].free_inodes);
2137                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2138                              &sbi->s_flex_groups[flex_group].free_clusters);
2139                 atomic_add(ext4_used_dirs_count(sb, gdp),
2140                            &sbi->s_flex_groups[flex_group].used_dirs);
2141         }
2142
2143         return 1;
2144 failed:
2145         return 0;
2146 }
2147
2148 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2149                                    struct ext4_group_desc *gdp)
2150 {
2151         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2152         __u16 crc = 0;
2153         __le32 le_group = cpu_to_le32(block_group);
2154         struct ext4_sb_info *sbi = EXT4_SB(sb);
2155
2156         if (ext4_has_metadata_csum(sbi->s_sb)) {
2157                 /* Use new metadata_csum algorithm */
2158                 __u32 csum32;
2159                 __u16 dummy_csum = 0;
2160
2161                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2162                                      sizeof(le_group));
2163                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2164                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2165                                      sizeof(dummy_csum));
2166                 offset += sizeof(dummy_csum);
2167                 if (offset < sbi->s_desc_size)
2168                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2169                                              sbi->s_desc_size - offset);
2170
2171                 crc = csum32 & 0xFFFF;
2172                 goto out;
2173         }
2174
2175         /* old crc16 code */
2176         if (!ext4_has_feature_gdt_csum(sb))
2177                 return 0;
2178
2179         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2180         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2181         crc = crc16(crc, (__u8 *)gdp, offset);
2182         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2183         /* for checksum of struct ext4_group_desc do the rest...*/
2184         if (ext4_has_feature_64bit(sb) &&
2185             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2186                 crc = crc16(crc, (__u8 *)gdp + offset,
2187                             le16_to_cpu(sbi->s_es->s_desc_size) -
2188                                 offset);
2189
2190 out:
2191         return cpu_to_le16(crc);
2192 }
2193
2194 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2195                                 struct ext4_group_desc *gdp)
2196 {
2197         if (ext4_has_group_desc_csum(sb) &&
2198             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2199                 return 0;
2200
2201         return 1;
2202 }
2203
2204 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2205                               struct ext4_group_desc *gdp)
2206 {
2207         if (!ext4_has_group_desc_csum(sb))
2208                 return;
2209         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2210 }
2211
2212 /* Called at mount-time, super-block is locked */
2213 static int ext4_check_descriptors(struct super_block *sb,
2214                                   ext4_fsblk_t sb_block,
2215                                   ext4_group_t *first_not_zeroed)
2216 {
2217         struct ext4_sb_info *sbi = EXT4_SB(sb);
2218         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2219         ext4_fsblk_t last_block;
2220         ext4_fsblk_t block_bitmap;
2221         ext4_fsblk_t inode_bitmap;
2222         ext4_fsblk_t inode_table;
2223         int flexbg_flag = 0;
2224         ext4_group_t i, grp = sbi->s_groups_count;
2225
2226         if (ext4_has_feature_flex_bg(sb))
2227                 flexbg_flag = 1;
2228
2229         ext4_debug("Checking group descriptors");
2230
2231         for (i = 0; i < sbi->s_groups_count; i++) {
2232                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2233
2234                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2235                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2236                 else
2237                         last_block = first_block +
2238                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2239
2240                 if ((grp == sbi->s_groups_count) &&
2241                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2242                         grp = i;
2243
2244                 block_bitmap = ext4_block_bitmap(sb, gdp);
2245                 if (block_bitmap == sb_block) {
2246                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2247                                  "Block bitmap for group %u overlaps "
2248                                  "superblock", i);
2249                 }
2250                 if (block_bitmap < first_block || block_bitmap > last_block) {
2251                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2252                                "Block bitmap for group %u not in group "
2253                                "(block %llu)!", i, block_bitmap);
2254                         return 0;
2255                 }
2256                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2257                 if (inode_bitmap == sb_block) {
2258                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2259                                  "Inode bitmap for group %u overlaps "
2260                                  "superblock", i);
2261                 }
2262                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2263                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2264                                "Inode bitmap for group %u not in group "
2265                                "(block %llu)!", i, inode_bitmap);
2266                         return 0;
2267                 }
2268                 inode_table = ext4_inode_table(sb, gdp);
2269                 if (inode_table == sb_block) {
2270                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2271                                  "Inode table for group %u overlaps "
2272                                  "superblock", i);
2273                 }
2274                 if (inode_table < first_block ||
2275                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2276                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2277                                "Inode table for group %u not in group "
2278                                "(block %llu)!", i, inode_table);
2279                         return 0;
2280                 }
2281                 ext4_lock_group(sb, i);
2282                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2283                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2284                                  "Checksum for group %u failed (%u!=%u)",
2285                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2286                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2287                         if (!(sb->s_flags & MS_RDONLY)) {
2288                                 ext4_unlock_group(sb, i);
2289                                 return 0;
2290                         }
2291                 }
2292                 ext4_unlock_group(sb, i);
2293                 if (!flexbg_flag)
2294                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2295         }
2296         if (NULL != first_not_zeroed)
2297                 *first_not_zeroed = grp;
2298         return 1;
2299 }
2300
2301 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2302  * the superblock) which were deleted from all directories, but held open by
2303  * a process at the time of a crash.  We walk the list and try to delete these
2304  * inodes at recovery time (only with a read-write filesystem).
2305  *
2306  * In order to keep the orphan inode chain consistent during traversal (in
2307  * case of crash during recovery), we link each inode into the superblock
2308  * orphan list_head and handle it the same way as an inode deletion during
2309  * normal operation (which journals the operations for us).
2310  *
2311  * We only do an iget() and an iput() on each inode, which is very safe if we
2312  * accidentally point at an in-use or already deleted inode.  The worst that
2313  * can happen in this case is that we get a "bit already cleared" message from
2314  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2315  * e2fsck was run on this filesystem, and it must have already done the orphan
2316  * inode cleanup for us, so we can safely abort without any further action.
2317  */
2318 static void ext4_orphan_cleanup(struct super_block *sb,
2319                                 struct ext4_super_block *es)
2320 {
2321         unsigned int s_flags = sb->s_flags;
2322         int nr_orphans = 0, nr_truncates = 0;
2323 #ifdef CONFIG_QUOTA
2324         int i;
2325 #endif
2326         if (!es->s_last_orphan) {
2327                 jbd_debug(4, "no orphan inodes to clean up\n");
2328                 return;
2329         }
2330
2331         if (bdev_read_only(sb->s_bdev)) {
2332                 ext4_msg(sb, KERN_ERR, "write access "
2333                         "unavailable, skipping orphan cleanup");
2334                 return;
2335         }
2336
2337         /* Check if feature set would not allow a r/w mount */
2338         if (!ext4_feature_set_ok(sb, 0)) {
2339                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2340                          "unknown ROCOMPAT features");
2341                 return;
2342         }
2343
2344         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2345                 /* don't clear list on RO mount w/ errors */
2346                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2347                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2348                                   "clearing orphan list.\n");
2349                         es->s_last_orphan = 0;
2350                 }
2351                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2352                 return;
2353         }
2354
2355         if (s_flags & MS_RDONLY) {
2356                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2357                 sb->s_flags &= ~MS_RDONLY;
2358         }
2359 #ifdef CONFIG_QUOTA
2360         /* Needed for iput() to work correctly and not trash data */
2361         sb->s_flags |= MS_ACTIVE;
2362         /* Turn on quotas so that they are updated correctly */
2363         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2364                 if (EXT4_SB(sb)->s_qf_names[i]) {
2365                         int ret = ext4_quota_on_mount(sb, i);
2366                         if (ret < 0)
2367                                 ext4_msg(sb, KERN_ERR,
2368                                         "Cannot turn on journaled "
2369                                         "quota: error %d", ret);
2370                 }
2371         }
2372 #endif
2373
2374         while (es->s_last_orphan) {
2375                 struct inode *inode;
2376
2377                 /*
2378                  * We may have encountered an error during cleanup; if
2379                  * so, skip the rest.
2380                  */
2381                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2382                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2383                         es->s_last_orphan = 0;
2384                         break;
2385                 }
2386
2387                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2388                 if (IS_ERR(inode)) {
2389                         es->s_last_orphan = 0;
2390                         break;
2391                 }
2392
2393                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2394                 dquot_initialize(inode);
2395                 if (inode->i_nlink) {
2396                         if (test_opt(sb, DEBUG))
2397                                 ext4_msg(sb, KERN_DEBUG,
2398                                         "%s: truncating inode %lu to %lld bytes",
2399                                         __func__, inode->i_ino, inode->i_size);
2400                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2401                                   inode->i_ino, inode->i_size);
2402                         inode_lock(inode);
2403                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2404                         ext4_truncate(inode);
2405                         inode_unlock(inode);
2406                         nr_truncates++;
2407                 } else {
2408                         if (test_opt(sb, DEBUG))
2409                                 ext4_msg(sb, KERN_DEBUG,
2410                                         "%s: deleting unreferenced inode %lu",
2411                                         __func__, inode->i_ino);
2412                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2413                                   inode->i_ino);
2414                         nr_orphans++;
2415                 }
2416                 iput(inode);  /* The delete magic happens here! */
2417         }
2418
2419 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2420
2421         if (nr_orphans)
2422                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2423                        PLURAL(nr_orphans));
2424         if (nr_truncates)
2425                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2426                        PLURAL(nr_truncates));
2427 #ifdef CONFIG_QUOTA
2428         /* Turn quotas off */
2429         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2430                 if (sb_dqopt(sb)->files[i])
2431                         dquot_quota_off(sb, i);
2432         }
2433 #endif
2434         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2435 }
2436
2437 /*
2438  * Maximal extent format file size.
2439  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2440  * extent format containers, within a sector_t, and within i_blocks
2441  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2442  * so that won't be a limiting factor.
2443  *
2444  * However there is other limiting factor. We do store extents in the form
2445  * of starting block and length, hence the resulting length of the extent
2446  * covering maximum file size must fit into on-disk format containers as
2447  * well. Given that length is always by 1 unit bigger than max unit (because
2448  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2449  *
2450  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2451  */
2452 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2453 {
2454         loff_t res;
2455         loff_t upper_limit = MAX_LFS_FILESIZE;
2456
2457         /* small i_blocks in vfs inode? */
2458         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2459                 /*
2460                  * CONFIG_LBDAF is not enabled implies the inode
2461                  * i_block represent total blocks in 512 bytes
2462                  * 32 == size of vfs inode i_blocks * 8
2463                  */
2464                 upper_limit = (1LL << 32) - 1;
2465
2466                 /* total blocks in file system block size */
2467                 upper_limit >>= (blkbits - 9);
2468                 upper_limit <<= blkbits;
2469         }
2470
2471         /*
2472          * 32-bit extent-start container, ee_block. We lower the maxbytes
2473          * by one fs block, so ee_len can cover the extent of maximum file
2474          * size
2475          */
2476         res = (1LL << 32) - 1;
2477         res <<= blkbits;
2478
2479         /* Sanity check against vm- & vfs- imposed limits */
2480         if (res > upper_limit)
2481                 res = upper_limit;
2482
2483         return res;
2484 }
2485
2486 /*
2487  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2488  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2489  * We need to be 1 filesystem block less than the 2^48 sector limit.
2490  */
2491 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2492 {
2493         loff_t res = EXT4_NDIR_BLOCKS;
2494         int meta_blocks;
2495         loff_t upper_limit;
2496         /* This is calculated to be the largest file size for a dense, block
2497          * mapped file such that the file's total number of 512-byte sectors,
2498          * including data and all indirect blocks, does not exceed (2^48 - 1).
2499          *
2500          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2501          * number of 512-byte sectors of the file.
2502          */
2503
2504         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2505                 /*
2506                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2507                  * the inode i_block field represents total file blocks in
2508                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2509                  */
2510                 upper_limit = (1LL << 32) - 1;
2511
2512                 /* total blocks in file system block size */
2513                 upper_limit >>= (bits - 9);
2514
2515         } else {
2516                 /*
2517                  * We use 48 bit ext4_inode i_blocks
2518                  * With EXT4_HUGE_FILE_FL set the i_blocks
2519                  * represent total number of blocks in
2520                  * file system block size
2521                  */
2522                 upper_limit = (1LL << 48) - 1;
2523
2524         }
2525
2526         /* indirect blocks */
2527         meta_blocks = 1;
2528         /* double indirect blocks */
2529         meta_blocks += 1 + (1LL << (bits-2));
2530         /* tripple indirect blocks */
2531         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2532
2533         upper_limit -= meta_blocks;
2534         upper_limit <<= bits;
2535
2536         res += 1LL << (bits-2);
2537         res += 1LL << (2*(bits-2));
2538         res += 1LL << (3*(bits-2));
2539         res <<= bits;
2540         if (res > upper_limit)
2541                 res = upper_limit;
2542
2543         if (res > MAX_LFS_FILESIZE)
2544                 res = MAX_LFS_FILESIZE;
2545
2546         return res;
2547 }
2548
2549 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2550                                    ext4_fsblk_t logical_sb_block, int nr)
2551 {
2552         struct ext4_sb_info *sbi = EXT4_SB(sb);
2553         ext4_group_t bg, first_meta_bg;
2554         int has_super = 0;
2555
2556         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2557
2558         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2559                 return logical_sb_block + nr + 1;
2560         bg = sbi->s_desc_per_block * nr;
2561         if (ext4_bg_has_super(sb, bg))
2562                 has_super = 1;
2563
2564         /*
2565          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2566          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2567          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2568          * compensate.
2569          */
2570         if (sb->s_blocksize == 1024 && nr == 0 &&
2571             le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) == 0)
2572                 has_super++;
2573
2574         return (has_super + ext4_group_first_block_no(sb, bg));
2575 }
2576
2577 /**
2578  * ext4_get_stripe_size: Get the stripe size.
2579  * @sbi: In memory super block info
2580  *
2581  * If we have specified it via mount option, then
2582  * use the mount option value. If the value specified at mount time is
2583  * greater than the blocks per group use the super block value.
2584  * If the super block value is greater than blocks per group return 0.
2585  * Allocator needs it be less than blocks per group.
2586  *
2587  */
2588 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2589 {
2590         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2591         unsigned long stripe_width =
2592                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2593         int ret;
2594
2595         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2596                 ret = sbi->s_stripe;
2597         else if (stripe_width <= sbi->s_blocks_per_group)
2598                 ret = stripe_width;
2599         else if (stride <= sbi->s_blocks_per_group)
2600                 ret = stride;
2601         else
2602                 ret = 0;
2603
2604         /*
2605          * If the stripe width is 1, this makes no sense and
2606          * we set it to 0 to turn off stripe handling code.
2607          */
2608         if (ret <= 1)
2609                 ret = 0;
2610
2611         return ret;
2612 }
2613
2614 /*
2615  * Check whether this filesystem can be mounted based on
2616  * the features present and the RDONLY/RDWR mount requested.
2617  * Returns 1 if this filesystem can be mounted as requested,
2618  * 0 if it cannot be.
2619  */
2620 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2621 {
2622         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2623                 ext4_msg(sb, KERN_ERR,
2624                         "Couldn't mount because of "
2625                         "unsupported optional features (%x)",
2626                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2627                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2628                 return 0;
2629         }
2630
2631         if (readonly)
2632                 return 1;
2633
2634         if (ext4_has_feature_readonly(sb)) {
2635                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2636                 sb->s_flags |= MS_RDONLY;
2637                 return 1;
2638         }
2639
2640         /* Check that feature set is OK for a read-write mount */
2641         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2642                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2643                          "unsupported optional features (%x)",
2644                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2645                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2646                 return 0;
2647         }
2648         /*
2649          * Large file size enabled file system can only be mounted
2650          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2651          */
2652         if (ext4_has_feature_huge_file(sb)) {
2653                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2654                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2655                                  "cannot be mounted RDWR without "
2656                                  "CONFIG_LBDAF");
2657                         return 0;
2658                 }
2659         }
2660         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2661                 ext4_msg(sb, KERN_ERR,
2662                          "Can't support bigalloc feature without "
2663                          "extents feature\n");
2664                 return 0;
2665         }
2666
2667 #ifndef CONFIG_QUOTA
2668         if (ext4_has_feature_quota(sb) && !readonly) {
2669                 ext4_msg(sb, KERN_ERR,
2670                          "Filesystem with quota feature cannot be mounted RDWR "
2671                          "without CONFIG_QUOTA");
2672                 return 0;
2673         }
2674         if (ext4_has_feature_project(sb) && !readonly) {
2675                 ext4_msg(sb, KERN_ERR,
2676                          "Filesystem with project quota feature cannot be mounted RDWR "
2677                          "without CONFIG_QUOTA");
2678                 return 0;
2679         }
2680 #endif  /* CONFIG_QUOTA */
2681         return 1;
2682 }
2683
2684 /*
2685  * This function is called once a day if we have errors logged
2686  * on the file system
2687  */
2688 static void print_daily_error_info(unsigned long arg)
2689 {
2690         struct super_block *sb = (struct super_block *) arg;
2691         struct ext4_sb_info *sbi;
2692         struct ext4_super_block *es;
2693
2694         sbi = EXT4_SB(sb);
2695         es = sbi->s_es;
2696
2697         if (es->s_error_count)
2698                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2699                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2700                          le32_to_cpu(es->s_error_count));
2701         if (es->s_first_error_time) {
2702                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2703                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2704                        (int) sizeof(es->s_first_error_func),
2705                        es->s_first_error_func,
2706                        le32_to_cpu(es->s_first_error_line));
2707                 if (es->s_first_error_ino)
2708                         printk(": inode %u",
2709                                le32_to_cpu(es->s_first_error_ino));
2710                 if (es->s_first_error_block)
2711                         printk(": block %llu", (unsigned long long)
2712                                le64_to_cpu(es->s_first_error_block));
2713                 printk("\n");
2714         }
2715         if (es->s_last_error_time) {
2716                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2717                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2718                        (int) sizeof(es->s_last_error_func),
2719                        es->s_last_error_func,
2720                        le32_to_cpu(es->s_last_error_line));
2721                 if (es->s_last_error_ino)
2722                         printk(": inode %u",
2723                                le32_to_cpu(es->s_last_error_ino));
2724                 if (es->s_last_error_block)
2725                         printk(": block %llu", (unsigned long long)
2726                                le64_to_cpu(es->s_last_error_block));
2727                 printk("\n");
2728         }
2729         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2730 }
2731
2732 /* Find next suitable group and run ext4_init_inode_table */
2733 static int ext4_run_li_request(struct ext4_li_request *elr)
2734 {
2735         struct ext4_group_desc *gdp = NULL;
2736         ext4_group_t group, ngroups;
2737         struct super_block *sb;
2738         unsigned long timeout = 0;
2739         int ret = 0;
2740
2741         sb = elr->lr_super;
2742         ngroups = EXT4_SB(sb)->s_groups_count;
2743
2744         sb_start_write(sb);
2745         for (group = elr->lr_next_group; group < ngroups; group++) {
2746                 gdp = ext4_get_group_desc(sb, group, NULL);
2747                 if (!gdp) {
2748                         ret = 1;
2749                         break;
2750                 }
2751
2752                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2753                         break;
2754         }
2755
2756         if (group >= ngroups)
2757                 ret = 1;
2758
2759         if (!ret) {
2760                 timeout = jiffies;
2761                 ret = ext4_init_inode_table(sb, group,
2762                                             elr->lr_timeout ? 0 : 1);
2763                 if (elr->lr_timeout == 0) {
2764                         timeout = (jiffies - timeout) *
2765                                   elr->lr_sbi->s_li_wait_mult;
2766                         elr->lr_timeout = timeout;
2767                 }
2768                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2769                 elr->lr_next_group = group + 1;
2770         }
2771         sb_end_write(sb);
2772
2773         return ret;
2774 }
2775
2776 /*
2777  * Remove lr_request from the list_request and free the
2778  * request structure. Should be called with li_list_mtx held
2779  */
2780 static void ext4_remove_li_request(struct ext4_li_request *elr)
2781 {
2782         struct ext4_sb_info *sbi;
2783
2784         if (!elr)
2785                 return;
2786
2787         sbi = elr->lr_sbi;
2788
2789         list_del(&elr->lr_request);
2790         sbi->s_li_request = NULL;
2791         kfree(elr);
2792 }
2793
2794 static void ext4_unregister_li_request(struct super_block *sb)
2795 {
2796         mutex_lock(&ext4_li_mtx);
2797         if (!ext4_li_info) {
2798                 mutex_unlock(&ext4_li_mtx);
2799                 return;
2800         }
2801
2802         mutex_lock(&ext4_li_info->li_list_mtx);
2803         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2804         mutex_unlock(&ext4_li_info->li_list_mtx);
2805         mutex_unlock(&ext4_li_mtx);
2806 }
2807
2808 static struct task_struct *ext4_lazyinit_task;
2809
2810 /*
2811  * This is the function where ext4lazyinit thread lives. It walks
2812  * through the request list searching for next scheduled filesystem.
2813  * When such a fs is found, run the lazy initialization request
2814  * (ext4_rn_li_request) and keep track of the time spend in this
2815  * function. Based on that time we compute next schedule time of
2816  * the request. When walking through the list is complete, compute
2817  * next waking time and put itself into sleep.
2818  */
2819 static int ext4_lazyinit_thread(void *arg)
2820 {
2821         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2822         struct list_head *pos, *n;
2823         struct ext4_li_request *elr;
2824         unsigned long next_wakeup, cur;
2825
2826         BUG_ON(NULL == eli);
2827
2828 cont_thread:
2829         while (true) {
2830                 next_wakeup = MAX_JIFFY_OFFSET;
2831
2832                 mutex_lock(&eli->li_list_mtx);
2833                 if (list_empty(&eli->li_request_list)) {
2834                         mutex_unlock(&eli->li_list_mtx);
2835                         goto exit_thread;
2836                 }
2837
2838                 list_for_each_safe(pos, n, &eli->li_request_list) {
2839                         elr = list_entry(pos, struct ext4_li_request,
2840                                          lr_request);
2841
2842                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2843                                 if (ext4_run_li_request(elr) != 0) {
2844                                         /* error, remove the lazy_init job */
2845                                         ext4_remove_li_request(elr);
2846                                         continue;
2847                                 }
2848                         }
2849
2850                         if (time_before(elr->lr_next_sched, next_wakeup))
2851                                 next_wakeup = elr->lr_next_sched;
2852                 }
2853                 mutex_unlock(&eli->li_list_mtx);
2854
2855                 try_to_freeze();
2856
2857                 cur = jiffies;
2858                 if ((time_after_eq(cur, next_wakeup)) ||
2859                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2860                         cond_resched();
2861                         continue;
2862                 }
2863
2864                 schedule_timeout_interruptible(next_wakeup - cur);
2865
2866                 if (kthread_should_stop()) {
2867                         ext4_clear_request_list();
2868                         goto exit_thread;
2869                 }
2870         }
2871
2872 exit_thread:
2873         /*
2874          * It looks like the request list is empty, but we need
2875          * to check it under the li_list_mtx lock, to prevent any
2876          * additions into it, and of course we should lock ext4_li_mtx
2877          * to atomically free the list and ext4_li_info, because at
2878          * this point another ext4 filesystem could be registering
2879          * new one.
2880          */
2881         mutex_lock(&ext4_li_mtx);
2882         mutex_lock(&eli->li_list_mtx);
2883         if (!list_empty(&eli->li_request_list)) {
2884                 mutex_unlock(&eli->li_list_mtx);
2885                 mutex_unlock(&ext4_li_mtx);
2886                 goto cont_thread;
2887         }
2888         mutex_unlock(&eli->li_list_mtx);
2889         kfree(ext4_li_info);
2890         ext4_li_info = NULL;
2891         mutex_unlock(&ext4_li_mtx);
2892
2893         return 0;
2894 }
2895
2896 static void ext4_clear_request_list(void)
2897 {
2898         struct list_head *pos, *n;
2899         struct ext4_li_request *elr;
2900
2901         mutex_lock(&ext4_li_info->li_list_mtx);
2902         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2903                 elr = list_entry(pos, struct ext4_li_request,
2904                                  lr_request);
2905                 ext4_remove_li_request(elr);
2906         }
2907         mutex_unlock(&ext4_li_info->li_list_mtx);
2908 }
2909
2910 static int ext4_run_lazyinit_thread(void)
2911 {
2912         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2913                                          ext4_li_info, "ext4lazyinit");
2914         if (IS_ERR(ext4_lazyinit_task)) {
2915                 int err = PTR_ERR(ext4_lazyinit_task);
2916                 ext4_clear_request_list();
2917                 kfree(ext4_li_info);
2918                 ext4_li_info = NULL;
2919                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2920                                  "initialization thread\n",
2921                                  err);
2922                 return err;
2923         }
2924         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2925         return 0;
2926 }
2927
2928 /*
2929  * Check whether it make sense to run itable init. thread or not.
2930  * If there is at least one uninitialized inode table, return
2931  * corresponding group number, else the loop goes through all
2932  * groups and return total number of groups.
2933  */
2934 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2935 {
2936         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2937         struct ext4_group_desc *gdp = NULL;
2938
2939         for (group = 0; group < ngroups; group++) {
2940                 gdp = ext4_get_group_desc(sb, group, NULL);
2941                 if (!gdp)
2942                         continue;
2943
2944                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2945                         break;
2946         }
2947
2948         return group;
2949 }
2950
2951 static int ext4_li_info_new(void)
2952 {
2953         struct ext4_lazy_init *eli = NULL;
2954
2955         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2956         if (!eli)
2957                 return -ENOMEM;
2958
2959         INIT_LIST_HEAD(&eli->li_request_list);
2960         mutex_init(&eli->li_list_mtx);
2961
2962         eli->li_state |= EXT4_LAZYINIT_QUIT;
2963
2964         ext4_li_info = eli;
2965
2966         return 0;
2967 }
2968
2969 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2970                                             ext4_group_t start)
2971 {
2972         struct ext4_sb_info *sbi = EXT4_SB(sb);
2973         struct ext4_li_request *elr;
2974
2975         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2976         if (!elr)
2977                 return NULL;
2978
2979         elr->lr_super = sb;
2980         elr->lr_sbi = sbi;
2981         elr->lr_next_group = start;
2982
2983         /*
2984          * Randomize first schedule time of the request to
2985          * spread the inode table initialization requests
2986          * better.
2987          */
2988         elr->lr_next_sched = jiffies + (prandom_u32() %
2989                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
2990         return elr;
2991 }
2992
2993 int ext4_register_li_request(struct super_block *sb,
2994                              ext4_group_t first_not_zeroed)
2995 {
2996         struct ext4_sb_info *sbi = EXT4_SB(sb);
2997         struct ext4_li_request *elr = NULL;
2998         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2999         int ret = 0;
3000
3001         mutex_lock(&ext4_li_mtx);
3002         if (sbi->s_li_request != NULL) {
3003                 /*
3004                  * Reset timeout so it can be computed again, because
3005                  * s_li_wait_mult might have changed.
3006                  */
3007                 sbi->s_li_request->lr_timeout = 0;
3008                 goto out;
3009         }
3010
3011         if (first_not_zeroed == ngroups ||
3012             (sb->s_flags & MS_RDONLY) ||
3013             !test_opt(sb, INIT_INODE_TABLE))
3014                 goto out;
3015
3016         elr = ext4_li_request_new(sb, first_not_zeroed);
3017         if (!elr) {
3018                 ret = -ENOMEM;
3019                 goto out;
3020         }
3021
3022         if (NULL == ext4_li_info) {
3023                 ret = ext4_li_info_new();
3024                 if (ret)
3025                         goto out;
3026         }
3027
3028         mutex_lock(&ext4_li_info->li_list_mtx);
3029         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3030         mutex_unlock(&ext4_li_info->li_list_mtx);
3031
3032         sbi->s_li_request = elr;
3033         /*
3034          * set elr to NULL here since it has been inserted to
3035          * the request_list and the removal and free of it is
3036          * handled by ext4_clear_request_list from now on.
3037          */
3038         elr = NULL;
3039
3040         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3041                 ret = ext4_run_lazyinit_thread();
3042                 if (ret)
3043                         goto out;
3044         }
3045 out:
3046         mutex_unlock(&ext4_li_mtx);
3047         if (ret)
3048                 kfree(elr);
3049         return ret;
3050 }
3051
3052 /*
3053  * We do not need to lock anything since this is called on
3054  * module unload.
3055  */
3056 static void ext4_destroy_lazyinit_thread(void)
3057 {
3058         /*
3059          * If thread exited earlier
3060          * there's nothing to be done.
3061          */
3062         if (!ext4_li_info || !ext4_lazyinit_task)
3063                 return;
3064
3065         kthread_stop(ext4_lazyinit_task);
3066 }
3067
3068 static int set_journal_csum_feature_set(struct super_block *sb)
3069 {
3070         int ret = 1;
3071         int compat, incompat;
3072         struct ext4_sb_info *sbi = EXT4_SB(sb);
3073
3074         if (ext4_has_metadata_csum(sb)) {
3075                 /* journal checksum v3 */
3076                 compat = 0;
3077                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3078         } else {
3079                 /* journal checksum v1 */
3080                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3081                 incompat = 0;
3082         }
3083
3084         jbd2_journal_clear_features(sbi->s_journal,
3085                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3086                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3087                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3088         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3089                 ret = jbd2_journal_set_features(sbi->s_journal,
3090                                 compat, 0,
3091                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3092                                 incompat);
3093         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3094                 ret = jbd2_journal_set_features(sbi->s_journal,
3095                                 compat, 0,
3096                                 incompat);
3097                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3098                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3099         } else {
3100                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3101                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3102         }
3103
3104         return ret;
3105 }
3106
3107 /*
3108  * Note: calculating the overhead so we can be compatible with
3109  * historical BSD practice is quite difficult in the face of
3110  * clusters/bigalloc.  This is because multiple metadata blocks from
3111  * different block group can end up in the same allocation cluster.
3112  * Calculating the exact overhead in the face of clustered allocation
3113  * requires either O(all block bitmaps) in memory or O(number of block
3114  * groups**2) in time.  We will still calculate the superblock for
3115  * older file systems --- and if we come across with a bigalloc file
3116  * system with zero in s_overhead_clusters the estimate will be close to
3117  * correct especially for very large cluster sizes --- but for newer
3118  * file systems, it's better to calculate this figure once at mkfs
3119  * time, and store it in the superblock.  If the superblock value is
3120  * present (even for non-bigalloc file systems), we will use it.
3121  */
3122 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3123                           char *buf)
3124 {
3125         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3126         struct ext4_group_desc  *gdp;
3127         ext4_fsblk_t            first_block, last_block, b;
3128         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3129         int                     s, j, count = 0;
3130
3131         if (!ext4_has_feature_bigalloc(sb))
3132                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3133                         sbi->s_itb_per_group + 2);
3134
3135         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3136                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3137         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3138         for (i = 0; i < ngroups; i++) {
3139                 gdp = ext4_get_group_desc(sb, i, NULL);
3140                 b = ext4_block_bitmap(sb, gdp);
3141                 if (b >= first_block && b <= last_block) {
3142                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3143                         count++;
3144                 }
3145                 b = ext4_inode_bitmap(sb, gdp);
3146                 if (b >= first_block && b <= last_block) {
3147                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3148                         count++;
3149                 }
3150                 b = ext4_inode_table(sb, gdp);
3151                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3152                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3153                                 int c = EXT4_B2C(sbi, b - first_block);
3154                                 ext4_set_bit(c, buf);
3155                                 count++;
3156                         }
3157                 if (i != grp)
3158                         continue;
3159                 s = 0;
3160                 if (ext4_bg_has_super(sb, grp)) {
3161                         ext4_set_bit(s++, buf);
3162                         count++;
3163                 }
3164                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3165                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3166                         count++;
3167                 }
3168         }
3169         if (!count)
3170                 return 0;
3171         return EXT4_CLUSTERS_PER_GROUP(sb) -
3172                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3173 }
3174
3175 /*
3176  * Compute the overhead and stash it in sbi->s_overhead
3177  */
3178 int ext4_calculate_overhead(struct super_block *sb)
3179 {
3180         struct ext4_sb_info *sbi = EXT4_SB(sb);
3181         struct ext4_super_block *es = sbi->s_es;
3182         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3183         ext4_fsblk_t overhead = 0;
3184         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3185
3186         if (!buf)
3187                 return -ENOMEM;
3188
3189         /*
3190          * Compute the overhead (FS structures).  This is constant
3191          * for a given filesystem unless the number of block groups
3192          * changes so we cache the previous value until it does.
3193          */
3194
3195         /*
3196          * All of the blocks before first_data_block are overhead
3197          */
3198         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3199
3200         /*
3201          * Add the overhead found in each block group
3202          */
3203         for (i = 0; i < ngroups; i++) {
3204                 int blks;
3205
3206                 blks = count_overhead(sb, i, buf);
3207                 overhead += blks;
3208                 if (blks)
3209                         memset(buf, 0, PAGE_SIZE);
3210                 cond_resched();
3211         }
3212         /* Add the internal journal blocks as well */
3213         if (sbi->s_journal && !sbi->journal_bdev)
3214                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3215
3216         sbi->s_overhead = overhead;
3217         smp_wmb();
3218         free_page((unsigned long) buf);
3219         return 0;
3220 }
3221
3222 static void ext4_set_resv_clusters(struct super_block *sb)
3223 {
3224         ext4_fsblk_t resv_clusters;
3225         struct ext4_sb_info *sbi = EXT4_SB(sb);
3226
3227         /*
3228          * There's no need to reserve anything when we aren't using extents.
3229          * The space estimates are exact, there are no unwritten extents,
3230          * hole punching doesn't need new metadata... This is needed especially
3231          * to keep ext2/3 backward compatibility.
3232          */
3233         if (!ext4_has_feature_extents(sb))
3234                 return;
3235         /*
3236          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3237          * This should cover the situations where we can not afford to run
3238          * out of space like for example punch hole, or converting
3239          * unwritten extents in delalloc path. In most cases such
3240          * allocation would require 1, or 2 blocks, higher numbers are
3241          * very rare.