]> git.openfabrics.org - ~shefty/rdma-dev.git/blob - fs/ext4/super.c
183ae3447f64f4c0435671d636c0cb0d0a0df7a1
[~shefty/rdma-dev.git] / fs / ext4 / super.c
1 /*
2  *  linux/fs/ext4/super.c
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/fs/minix/inode.c
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  *
15  *  Big-endian to little-endian byte-swapping/bitmaps by
16  *        David S. Miller (davem@caip.rutgers.edu), 1995
17  */
18
19 #include <linux/module.h>
20 #include <linux/string.h>
21 #include <linux/fs.h>
22 #include <linux/time.h>
23 #include <linux/vmalloc.h>
24 #include <linux/jbd2.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/parser.h>
29 #include <linux/buffer_head.h>
30 #include <linux/exportfs.h>
31 #include <linux/vfs.h>
32 #include <linux/random.h>
33 #include <linux/mount.h>
34 #include <linux/namei.h>
35 #include <linux/quotaops.h>
36 #include <linux/seq_file.h>
37 #include <linux/proc_fs.h>
38 #include <linux/ctype.h>
39 #include <linux/log2.h>
40 #include <linux/crc16.h>
41 #include <linux/cleancache.h>
42 #include <asm/uaccess.h>
43
44 #include <linux/kthread.h>
45 #include <linux/freezer.h>
46
47 #include "ext4.h"
48 #include "ext4_extents.h"       /* Needed for trace points definition */
49 #include "ext4_jbd2.h"
50 #include "xattr.h"
51 #include "acl.h"
52 #include "mballoc.h"
53
54 #define CREATE_TRACE_POINTS
55 #include <trace/events/ext4.h>
56
57 static struct proc_dir_entry *ext4_proc_root;
58 static struct kset *ext4_kset;
59 static struct ext4_lazy_init *ext4_li_info;
60 static struct mutex ext4_li_mtx;
61 static struct ext4_features *ext4_feat;
62
63 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
64                              unsigned long journal_devnum);
65 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
66 static int ext4_commit_super(struct super_block *sb, int sync);
67 static void ext4_mark_recovery_complete(struct super_block *sb,
68                                         struct ext4_super_block *es);
69 static void ext4_clear_journal_err(struct super_block *sb,
70                                    struct ext4_super_block *es);
71 static int ext4_sync_fs(struct super_block *sb, int wait);
72 static const char *ext4_decode_error(struct super_block *sb, int errno,
73                                      char nbuf[16]);
74 static int ext4_remount(struct super_block *sb, int *flags, char *data);
75 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
76 static int ext4_unfreeze(struct super_block *sb);
77 static int ext4_freeze(struct super_block *sb);
78 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
79                        const char *dev_name, void *data);
80 static inline int ext2_feature_set_ok(struct super_block *sb);
81 static inline int ext3_feature_set_ok(struct super_block *sb);
82 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
83 static void ext4_destroy_lazyinit_thread(void);
84 static void ext4_unregister_li_request(struct super_block *sb);
85 static void ext4_clear_request_list(void);
86
87 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
88 static struct file_system_type ext2_fs_type = {
89         .owner          = THIS_MODULE,
90         .name           = "ext2",
91         .mount          = ext4_mount,
92         .kill_sb        = kill_block_super,
93         .fs_flags       = FS_REQUIRES_DEV,
94 };
95 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
96 #else
97 #define IS_EXT2_SB(sb) (0)
98 #endif
99
100
101 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
102 static struct file_system_type ext3_fs_type = {
103         .owner          = THIS_MODULE,
104         .name           = "ext3",
105         .mount          = ext4_mount,
106         .kill_sb        = kill_block_super,
107         .fs_flags       = FS_REQUIRES_DEV,
108 };
109 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
110 #else
111 #define IS_EXT3_SB(sb) (0)
112 #endif
113
114 static int ext4_verify_csum_type(struct super_block *sb,
115                                  struct ext4_super_block *es)
116 {
117         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
118                                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
119                 return 1;
120
121         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
122 }
123
124 static __le32 ext4_superblock_csum(struct super_block *sb,
125                                    struct ext4_super_block *es)
126 {
127         struct ext4_sb_info *sbi = EXT4_SB(sb);
128         int offset = offsetof(struct ext4_super_block, s_checksum);
129         __u32 csum;
130
131         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
132
133         return cpu_to_le32(csum);
134 }
135
136 int ext4_superblock_csum_verify(struct super_block *sb,
137                                 struct ext4_super_block *es)
138 {
139         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
140                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
141                 return 1;
142
143         return es->s_checksum == ext4_superblock_csum(sb, es);
144 }
145
146 void ext4_superblock_csum_set(struct super_block *sb)
147 {
148         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
149
150         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
151                 EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
152                 return;
153
154         es->s_checksum = ext4_superblock_csum(sb, es);
155 }
156
157 void *ext4_kvmalloc(size_t size, gfp_t flags)
158 {
159         void *ret;
160
161         ret = kmalloc(size, flags);
162         if (!ret)
163                 ret = __vmalloc(size, flags, PAGE_KERNEL);
164         return ret;
165 }
166
167 void *ext4_kvzalloc(size_t size, gfp_t flags)
168 {
169         void *ret;
170
171         ret = kzalloc(size, flags);
172         if (!ret)
173                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
174         return ret;
175 }
176
177 void ext4_kvfree(void *ptr)
178 {
179         if (is_vmalloc_addr(ptr))
180                 vfree(ptr);
181         else
182                 kfree(ptr);
183
184 }
185
186 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
187                                struct ext4_group_desc *bg)
188 {
189         return le32_to_cpu(bg->bg_block_bitmap_lo) |
190                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
191                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
192 }
193
194 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
195                                struct ext4_group_desc *bg)
196 {
197         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
198                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
199                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
200 }
201
202 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
203                               struct ext4_group_desc *bg)
204 {
205         return le32_to_cpu(bg->bg_inode_table_lo) |
206                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
207                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
208 }
209
210 __u32 ext4_free_group_clusters(struct super_block *sb,
211                                struct ext4_group_desc *bg)
212 {
213         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
214                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
215                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
216 }
217
218 __u32 ext4_free_inodes_count(struct super_block *sb,
219                               struct ext4_group_desc *bg)
220 {
221         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
222                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
223                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
224 }
225
226 __u32 ext4_used_dirs_count(struct super_block *sb,
227                               struct ext4_group_desc *bg)
228 {
229         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
230                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
231                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
232 }
233
234 __u32 ext4_itable_unused_count(struct super_block *sb,
235                               struct ext4_group_desc *bg)
236 {
237         return le16_to_cpu(bg->bg_itable_unused_lo) |
238                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
239                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
240 }
241
242 void ext4_block_bitmap_set(struct super_block *sb,
243                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
244 {
245         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
246         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
247                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
248 }
249
250 void ext4_inode_bitmap_set(struct super_block *sb,
251                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
252 {
253         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
254         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
255                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
256 }
257
258 void ext4_inode_table_set(struct super_block *sb,
259                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
260 {
261         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
262         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
263                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
264 }
265
266 void ext4_free_group_clusters_set(struct super_block *sb,
267                                   struct ext4_group_desc *bg, __u32 count)
268 {
269         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
270         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
271                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
272 }
273
274 void ext4_free_inodes_set(struct super_block *sb,
275                           struct ext4_group_desc *bg, __u32 count)
276 {
277         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
278         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
279                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
280 }
281
282 void ext4_used_dirs_set(struct super_block *sb,
283                           struct ext4_group_desc *bg, __u32 count)
284 {
285         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
286         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
287                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
288 }
289
290 void ext4_itable_unused_set(struct super_block *sb,
291                           struct ext4_group_desc *bg, __u32 count)
292 {
293         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
294         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
295                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
296 }
297
298
299 /* Just increment the non-pointer handle value */
300 static handle_t *ext4_get_nojournal(void)
301 {
302         handle_t *handle = current->journal_info;
303         unsigned long ref_cnt = (unsigned long)handle;
304
305         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
306
307         ref_cnt++;
308         handle = (handle_t *)ref_cnt;
309
310         current->journal_info = handle;
311         return handle;
312 }
313
314
315 /* Decrement the non-pointer handle value */
316 static void ext4_put_nojournal(handle_t *handle)
317 {
318         unsigned long ref_cnt = (unsigned long)handle;
319
320         BUG_ON(ref_cnt == 0);
321
322         ref_cnt--;
323         handle = (handle_t *)ref_cnt;
324
325         current->journal_info = handle;
326 }
327
328 /*
329  * Wrappers for jbd2_journal_start/end.
330  */
331 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
332 {
333         journal_t *journal;
334
335         trace_ext4_journal_start(sb, nblocks, _RET_IP_);
336         if (sb->s_flags & MS_RDONLY)
337                 return ERR_PTR(-EROFS);
338
339         WARN_ON(sb->s_writers.frozen == SB_FREEZE_COMPLETE);
340         journal = EXT4_SB(sb)->s_journal;
341         if (!journal)
342                 return ext4_get_nojournal();
343         /*
344          * Special case here: if the journal has aborted behind our
345          * backs (eg. EIO in the commit thread), then we still need to
346          * take the FS itself readonly cleanly.
347          */
348         if (is_journal_aborted(journal)) {
349                 ext4_abort(sb, "Detected aborted journal");
350                 return ERR_PTR(-EROFS);
351         }
352         return jbd2_journal_start(journal, nblocks);
353 }
354
355 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
356 {
357         struct super_block *sb;
358         int err;
359         int rc;
360
361         if (!ext4_handle_valid(handle)) {
362                 ext4_put_nojournal(handle);
363                 return 0;
364         }
365         sb = handle->h_transaction->t_journal->j_private;
366         err = handle->h_err;
367         rc = jbd2_journal_stop(handle);
368
369         if (!err)
370                 err = rc;
371         if (err)
372                 __ext4_std_error(sb, where, line, err);
373         return err;
374 }
375
376 void ext4_journal_abort_handle(const char *caller, unsigned int line,
377                                const char *err_fn, struct buffer_head *bh,
378                                handle_t *handle, int err)
379 {
380         char nbuf[16];
381         const char *errstr = ext4_decode_error(NULL, err, nbuf);
382
383         BUG_ON(!ext4_handle_valid(handle));
384
385         if (bh)
386                 BUFFER_TRACE(bh, "abort");
387
388         if (!handle->h_err)
389                 handle->h_err = err;
390
391         if (is_handle_aborted(handle))
392                 return;
393
394         printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",
395                caller, line, errstr, err_fn);
396
397         jbd2_journal_abort_handle(handle);
398 }
399
400 static void __save_error_info(struct super_block *sb, const char *func,
401                             unsigned int line)
402 {
403         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
404
405         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
406         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
407         es->s_last_error_time = cpu_to_le32(get_seconds());
408         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
409         es->s_last_error_line = cpu_to_le32(line);
410         if (!es->s_first_error_time) {
411                 es->s_first_error_time = es->s_last_error_time;
412                 strncpy(es->s_first_error_func, func,
413                         sizeof(es->s_first_error_func));
414                 es->s_first_error_line = cpu_to_le32(line);
415                 es->s_first_error_ino = es->s_last_error_ino;
416                 es->s_first_error_block = es->s_last_error_block;
417         }
418         /*
419          * Start the daily error reporting function if it hasn't been
420          * started already
421          */
422         if (!es->s_error_count)
423                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
424         le32_add_cpu(&es->s_error_count, 1);
425 }
426
427 static void save_error_info(struct super_block *sb, const char *func,
428                             unsigned int line)
429 {
430         __save_error_info(sb, func, line);
431         ext4_commit_super(sb, 1);
432 }
433
434 /*
435  * The del_gendisk() function uninitializes the disk-specific data
436  * structures, including the bdi structure, without telling anyone
437  * else.  Once this happens, any attempt to call mark_buffer_dirty()
438  * (for example, by ext4_commit_super), will cause a kernel OOPS.
439  * This is a kludge to prevent these oops until we can put in a proper
440  * hook in del_gendisk() to inform the VFS and file system layers.
441  */
442 static int block_device_ejected(struct super_block *sb)
443 {
444         struct inode *bd_inode = sb->s_bdev->bd_inode;
445         struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
446
447         return bdi->dev == NULL;
448 }
449
450 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
451 {
452         struct super_block              *sb = journal->j_private;
453         struct ext4_sb_info             *sbi = EXT4_SB(sb);
454         int                             error = is_journal_aborted(journal);
455         struct ext4_journal_cb_entry    *jce, *tmp;
456
457         spin_lock(&sbi->s_md_lock);
458         list_for_each_entry_safe(jce, tmp, &txn->t_private_list, jce_list) {
459                 list_del_init(&jce->jce_list);
460                 spin_unlock(&sbi->s_md_lock);
461                 jce->jce_func(sb, jce, error);
462                 spin_lock(&sbi->s_md_lock);
463         }
464         spin_unlock(&sbi->s_md_lock);
465 }
466
467 /* Deal with the reporting of failure conditions on a filesystem such as
468  * inconsistencies detected or read IO failures.
469  *
470  * On ext2, we can store the error state of the filesystem in the
471  * superblock.  That is not possible on ext4, because we may have other
472  * write ordering constraints on the superblock which prevent us from
473  * writing it out straight away; and given that the journal is about to
474  * be aborted, we can't rely on the current, or future, transactions to
475  * write out the superblock safely.
476  *
477  * We'll just use the jbd2_journal_abort() error code to record an error in
478  * the journal instead.  On recovery, the journal will complain about
479  * that error until we've noted it down and cleared it.
480  */
481
482 static void ext4_handle_error(struct super_block *sb)
483 {
484         if (sb->s_flags & MS_RDONLY)
485                 return;
486
487         if (!test_opt(sb, ERRORS_CONT)) {
488                 journal_t *journal = EXT4_SB(sb)->s_journal;
489
490                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
491                 if (journal)
492                         jbd2_journal_abort(journal, -EIO);
493         }
494         if (test_opt(sb, ERRORS_RO)) {
495                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
496                 sb->s_flags |= MS_RDONLY;
497         }
498         if (test_opt(sb, ERRORS_PANIC))
499                 panic("EXT4-fs (device %s): panic forced after error\n",
500                         sb->s_id);
501 }
502
503 void __ext4_error(struct super_block *sb, const char *function,
504                   unsigned int line, const char *fmt, ...)
505 {
506         struct va_format vaf;
507         va_list args;
508
509         va_start(args, fmt);
510         vaf.fmt = fmt;
511         vaf.va = &args;
512         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
513                sb->s_id, function, line, current->comm, &vaf);
514         va_end(args);
515         save_error_info(sb, function, line);
516
517         ext4_handle_error(sb);
518 }
519
520 void ext4_error_inode(struct inode *inode, const char *function,
521                       unsigned int line, ext4_fsblk_t block,
522                       const char *fmt, ...)
523 {
524         va_list args;
525         struct va_format vaf;
526         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
527
528         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
529         es->s_last_error_block = cpu_to_le64(block);
530         save_error_info(inode->i_sb, function, line);
531         va_start(args, fmt);
532         vaf.fmt = fmt;
533         vaf.va = &args;
534         if (block)
535                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
536                        "inode #%lu: block %llu: comm %s: %pV\n",
537                        inode->i_sb->s_id, function, line, inode->i_ino,
538                        block, current->comm, &vaf);
539         else
540                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
541                        "inode #%lu: comm %s: %pV\n",
542                        inode->i_sb->s_id, function, line, inode->i_ino,
543                        current->comm, &vaf);
544         va_end(args);
545
546         ext4_handle_error(inode->i_sb);
547 }
548
549 void ext4_error_file(struct file *file, const char *function,
550                      unsigned int line, ext4_fsblk_t block,
551                      const char *fmt, ...)
552 {
553         va_list args;
554         struct va_format vaf;
555         struct ext4_super_block *es;
556         struct inode *inode = file->f_dentry->d_inode;
557         char pathname[80], *path;
558
559         es = EXT4_SB(inode->i_sb)->s_es;
560         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
561         save_error_info(inode->i_sb, function, line);
562         path = d_path(&(file->f_path), pathname, sizeof(pathname));
563         if (IS_ERR(path))
564                 path = "(unknown)";
565         va_start(args, fmt);
566         vaf.fmt = fmt;
567         vaf.va = &args;
568         if (block)
569                 printk(KERN_CRIT
570                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
571                        "block %llu: comm %s: path %s: %pV\n",
572                        inode->i_sb->s_id, function, line, inode->i_ino,
573                        block, current->comm, path, &vaf);
574         else
575                 printk(KERN_CRIT
576                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
577                        "comm %s: path %s: %pV\n",
578                        inode->i_sb->s_id, function, line, inode->i_ino,
579                        current->comm, path, &vaf);
580         va_end(args);
581
582         ext4_handle_error(inode->i_sb);
583 }
584
585 static const char *ext4_decode_error(struct super_block *sb, int errno,
586                                      char nbuf[16])
587 {
588         char *errstr = NULL;
589
590         switch (errno) {
591         case -EIO:
592                 errstr = "IO failure";
593                 break;
594         case -ENOMEM:
595                 errstr = "Out of memory";
596                 break;
597         case -EROFS:
598                 if (!sb || (EXT4_SB(sb)->s_journal &&
599                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
600                         errstr = "Journal has aborted";
601                 else
602                         errstr = "Readonly filesystem";
603                 break;
604         default:
605                 /* If the caller passed in an extra buffer for unknown
606                  * errors, textualise them now.  Else we just return
607                  * NULL. */
608                 if (nbuf) {
609                         /* Check for truncated error codes... */
610                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
611                                 errstr = nbuf;
612                 }
613                 break;
614         }
615
616         return errstr;
617 }
618
619 /* __ext4_std_error decodes expected errors from journaling functions
620  * automatically and invokes the appropriate error response.  */
621
622 void __ext4_std_error(struct super_block *sb, const char *function,
623                       unsigned int line, int errno)
624 {
625         char nbuf[16];
626         const char *errstr;
627
628         /* Special case: if the error is EROFS, and we're not already
629          * inside a transaction, then there's really no point in logging
630          * an error. */
631         if (errno == -EROFS && journal_current_handle() == NULL &&
632             (sb->s_flags & MS_RDONLY))
633                 return;
634
635         errstr = ext4_decode_error(sb, errno, nbuf);
636         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
637                sb->s_id, function, line, errstr);
638         save_error_info(sb, function, line);
639
640         ext4_handle_error(sb);
641 }
642
643 /*
644  * ext4_abort is a much stronger failure handler than ext4_error.  The
645  * abort function may be used to deal with unrecoverable failures such
646  * as journal IO errors or ENOMEM at a critical moment in log management.
647  *
648  * We unconditionally force the filesystem into an ABORT|READONLY state,
649  * unless the error response on the fs has been set to panic in which
650  * case we take the easy way out and panic immediately.
651  */
652
653 void __ext4_abort(struct super_block *sb, const char *function,
654                 unsigned int line, const char *fmt, ...)
655 {
656         va_list args;
657
658         save_error_info(sb, function, line);
659         va_start(args, fmt);
660         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
661                function, line);
662         vprintk(fmt, args);
663         printk("\n");
664         va_end(args);
665
666         if ((sb->s_flags & MS_RDONLY) == 0) {
667                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
668                 sb->s_flags |= MS_RDONLY;
669                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
670                 if (EXT4_SB(sb)->s_journal)
671                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
672                 save_error_info(sb, function, line);
673         }
674         if (test_opt(sb, ERRORS_PANIC))
675                 panic("EXT4-fs panic from previous error\n");
676 }
677
678 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
679 {
680         struct va_format vaf;
681         va_list args;
682
683         va_start(args, fmt);
684         vaf.fmt = fmt;
685         vaf.va = &args;
686         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
687         va_end(args);
688 }
689
690 void __ext4_warning(struct super_block *sb, const char *function,
691                     unsigned int line, const char *fmt, ...)
692 {
693         struct va_format vaf;
694         va_list args;
695
696         va_start(args, fmt);
697         vaf.fmt = fmt;
698         vaf.va = &args;
699         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
700                sb->s_id, function, line, &vaf);
701         va_end(args);
702 }
703
704 void __ext4_grp_locked_error(const char *function, unsigned int line,
705                              struct super_block *sb, ext4_group_t grp,
706                              unsigned long ino, ext4_fsblk_t block,
707                              const char *fmt, ...)
708 __releases(bitlock)
709 __acquires(bitlock)
710 {
711         struct va_format vaf;
712         va_list args;
713         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
714
715         es->s_last_error_ino = cpu_to_le32(ino);
716         es->s_last_error_block = cpu_to_le64(block);
717         __save_error_info(sb, function, line);
718
719         va_start(args, fmt);
720
721         vaf.fmt = fmt;
722         vaf.va = &args;
723         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
724                sb->s_id, function, line, grp);
725         if (ino)
726                 printk(KERN_CONT "inode %lu: ", ino);
727         if (block)
728                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
729         printk(KERN_CONT "%pV\n", &vaf);
730         va_end(args);
731
732         if (test_opt(sb, ERRORS_CONT)) {
733                 ext4_commit_super(sb, 0);
734                 return;
735         }
736
737         ext4_unlock_group(sb, grp);
738         ext4_handle_error(sb);
739         /*
740          * We only get here in the ERRORS_RO case; relocking the group
741          * may be dangerous, but nothing bad will happen since the
742          * filesystem will have already been marked read/only and the
743          * journal has been aborted.  We return 1 as a hint to callers
744          * who might what to use the return value from
745          * ext4_grp_locked_error() to distinguish between the
746          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
747          * aggressively from the ext4 function in question, with a
748          * more appropriate error code.
749          */
750         ext4_lock_group(sb, grp);
751         return;
752 }
753
754 void ext4_update_dynamic_rev(struct super_block *sb)
755 {
756         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
757
758         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
759                 return;
760
761         ext4_warning(sb,
762                      "updating to rev %d because of new feature flag, "
763                      "running e2fsck is recommended",
764                      EXT4_DYNAMIC_REV);
765
766         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
767         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
768         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
769         /* leave es->s_feature_*compat flags alone */
770         /* es->s_uuid will be set by e2fsck if empty */
771
772         /*
773          * The rest of the superblock fields should be zero, and if not it
774          * means they are likely already in use, so leave them alone.  We
775          * can leave it up to e2fsck to clean up any inconsistencies there.
776          */
777 }
778
779 /*
780  * Open the external journal device
781  */
782 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
783 {
784         struct block_device *bdev;
785         char b[BDEVNAME_SIZE];
786
787         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
788         if (IS_ERR(bdev))
789                 goto fail;
790         return bdev;
791
792 fail:
793         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
794                         __bdevname(dev, b), PTR_ERR(bdev));
795         return NULL;
796 }
797
798 /*
799  * Release the journal device
800  */
801 static int ext4_blkdev_put(struct block_device *bdev)
802 {
803         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
804 }
805
806 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
807 {
808         struct block_device *bdev;
809         int ret = -ENODEV;
810
811         bdev = sbi->journal_bdev;
812         if (bdev) {
813                 ret = ext4_blkdev_put(bdev);
814                 sbi->journal_bdev = NULL;
815         }
816         return ret;
817 }
818
819 static inline struct inode *orphan_list_entry(struct list_head *l)
820 {
821         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
822 }
823
824 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
825 {
826         struct list_head *l;
827
828         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
829                  le32_to_cpu(sbi->s_es->s_last_orphan));
830
831         printk(KERN_ERR "sb_info orphan list:\n");
832         list_for_each(l, &sbi->s_orphan) {
833                 struct inode *inode = orphan_list_entry(l);
834                 printk(KERN_ERR "  "
835                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
836                        inode->i_sb->s_id, inode->i_ino, inode,
837                        inode->i_mode, inode->i_nlink,
838                        NEXT_ORPHAN(inode));
839         }
840 }
841
842 static void ext4_put_super(struct super_block *sb)
843 {
844         struct ext4_sb_info *sbi = EXT4_SB(sb);
845         struct ext4_super_block *es = sbi->s_es;
846         int i, err;
847
848         ext4_unregister_li_request(sb);
849         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
850
851         flush_workqueue(sbi->dio_unwritten_wq);
852         destroy_workqueue(sbi->dio_unwritten_wq);
853
854         if (sbi->s_journal) {
855                 err = jbd2_journal_destroy(sbi->s_journal);
856                 sbi->s_journal = NULL;
857                 if (err < 0)
858                         ext4_abort(sb, "Couldn't clean up the journal");
859         }
860
861         del_timer(&sbi->s_err_report);
862         ext4_release_system_zone(sb);
863         ext4_mb_release(sb);
864         ext4_ext_release(sb);
865         ext4_xattr_put_super(sb);
866
867         if (!(sb->s_flags & MS_RDONLY)) {
868                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
869                 es->s_state = cpu_to_le16(sbi->s_mount_state);
870         }
871         if (!(sb->s_flags & MS_RDONLY))
872                 ext4_commit_super(sb, 1);
873
874         if (sbi->s_proc) {
875                 remove_proc_entry("options", sbi->s_proc);
876                 remove_proc_entry(sb->s_id, ext4_proc_root);
877         }
878         kobject_del(&sbi->s_kobj);
879
880         for (i = 0; i < sbi->s_gdb_count; i++)
881                 brelse(sbi->s_group_desc[i]);
882         ext4_kvfree(sbi->s_group_desc);
883         ext4_kvfree(sbi->s_flex_groups);
884         percpu_counter_destroy(&sbi->s_freeclusters_counter);
885         percpu_counter_destroy(&sbi->s_freeinodes_counter);
886         percpu_counter_destroy(&sbi->s_dirs_counter);
887         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
888         brelse(sbi->s_sbh);
889 #ifdef CONFIG_QUOTA
890         for (i = 0; i < MAXQUOTAS; i++)
891                 kfree(sbi->s_qf_names[i]);
892 #endif
893
894         /* Debugging code just in case the in-memory inode orphan list
895          * isn't empty.  The on-disk one can be non-empty if we've
896          * detected an error and taken the fs readonly, but the
897          * in-memory list had better be clean by this point. */
898         if (!list_empty(&sbi->s_orphan))
899                 dump_orphan_list(sb, sbi);
900         J_ASSERT(list_empty(&sbi->s_orphan));
901
902         invalidate_bdev(sb->s_bdev);
903         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
904                 /*
905                  * Invalidate the journal device's buffers.  We don't want them
906                  * floating about in memory - the physical journal device may
907                  * hotswapped, and it breaks the `ro-after' testing code.
908                  */
909                 sync_blockdev(sbi->journal_bdev);
910                 invalidate_bdev(sbi->journal_bdev);
911                 ext4_blkdev_remove(sbi);
912         }
913         if (sbi->s_mmp_tsk)
914                 kthread_stop(sbi->s_mmp_tsk);
915         sb->s_fs_info = NULL;
916         /*
917          * Now that we are completely done shutting down the
918          * superblock, we need to actually destroy the kobject.
919          */
920         kobject_put(&sbi->s_kobj);
921         wait_for_completion(&sbi->s_kobj_unregister);
922         if (sbi->s_chksum_driver)
923                 crypto_free_shash(sbi->s_chksum_driver);
924         kfree(sbi->s_blockgroup_lock);
925         kfree(sbi);
926 }
927
928 static struct kmem_cache *ext4_inode_cachep;
929
930 /*
931  * Called inside transaction, so use GFP_NOFS
932  */
933 static struct inode *ext4_alloc_inode(struct super_block *sb)
934 {
935         struct ext4_inode_info *ei;
936
937         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
938         if (!ei)
939                 return NULL;
940
941         ei->vfs_inode.i_version = 1;
942         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
943         INIT_LIST_HEAD(&ei->i_prealloc_list);
944         spin_lock_init(&ei->i_prealloc_lock);
945         ext4_es_init_tree(&ei->i_es_tree);
946         rwlock_init(&ei->i_es_lock);
947         ei->i_reserved_data_blocks = 0;
948         ei->i_reserved_meta_blocks = 0;
949         ei->i_allocated_meta_blocks = 0;
950         ei->i_da_metadata_calc_len = 0;
951         ei->i_da_metadata_calc_last_lblock = 0;
952         spin_lock_init(&(ei->i_block_reservation_lock));
953 #ifdef CONFIG_QUOTA
954         ei->i_reserved_quota = 0;
955 #endif
956         ei->jinode = NULL;
957         INIT_LIST_HEAD(&ei->i_completed_io_list);
958         spin_lock_init(&ei->i_completed_io_lock);
959         ei->i_sync_tid = 0;
960         ei->i_datasync_tid = 0;
961         atomic_set(&ei->i_ioend_count, 0);
962         atomic_set(&ei->i_unwritten, 0);
963
964         return &ei->vfs_inode;
965 }
966
967 static int ext4_drop_inode(struct inode *inode)
968 {
969         int drop = generic_drop_inode(inode);
970
971         trace_ext4_drop_inode(inode, drop);
972         return drop;
973 }
974
975 static void ext4_i_callback(struct rcu_head *head)
976 {
977         struct inode *inode = container_of(head, struct inode, i_rcu);
978         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
979 }
980
981 static void ext4_destroy_inode(struct inode *inode)
982 {
983         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
984                 ext4_msg(inode->i_sb, KERN_ERR,
985                          "Inode %lu (%p): orphan list check failed!",
986                          inode->i_ino, EXT4_I(inode));
987                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
988                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
989                                 true);
990                 dump_stack();
991         }
992         call_rcu(&inode->i_rcu, ext4_i_callback);
993 }
994
995 static void init_once(void *foo)
996 {
997         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
998
999         INIT_LIST_HEAD(&ei->i_orphan);
1000         init_rwsem(&ei->xattr_sem);
1001         init_rwsem(&ei->i_data_sem);
1002         inode_init_once(&ei->vfs_inode);
1003 }
1004
1005 static int init_inodecache(void)
1006 {
1007         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
1008                                              sizeof(struct ext4_inode_info),
1009                                              0, (SLAB_RECLAIM_ACCOUNT|
1010                                                 SLAB_MEM_SPREAD),
1011                                              init_once);
1012         if (ext4_inode_cachep == NULL)
1013                 return -ENOMEM;
1014         return 0;
1015 }
1016
1017 static void destroy_inodecache(void)
1018 {
1019         /*
1020          * Make sure all delayed rcu free inodes are flushed before we
1021          * destroy cache.
1022          */
1023         rcu_barrier();
1024         kmem_cache_destroy(ext4_inode_cachep);
1025 }
1026
1027 void ext4_clear_inode(struct inode *inode)
1028 {
1029         invalidate_inode_buffers(inode);
1030         clear_inode(inode);
1031         dquot_drop(inode);
1032         ext4_discard_preallocations(inode);
1033         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1034         if (EXT4_I(inode)->jinode) {
1035                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1036                                                EXT4_I(inode)->jinode);
1037                 jbd2_free_inode(EXT4_I(inode)->jinode);
1038                 EXT4_I(inode)->jinode = NULL;
1039         }
1040 }
1041
1042 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1043                                         u64 ino, u32 generation)
1044 {
1045         struct inode *inode;
1046
1047         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1048                 return ERR_PTR(-ESTALE);
1049         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1050                 return ERR_PTR(-ESTALE);
1051
1052         /* iget isn't really right if the inode is currently unallocated!!
1053          *
1054          * ext4_read_inode will return a bad_inode if the inode had been
1055          * deleted, so we should be safe.
1056          *
1057          * Currently we don't know the generation for parent directory, so
1058          * a generation of 0 means "accept any"
1059          */
1060         inode = ext4_iget(sb, ino);
1061         if (IS_ERR(inode))
1062                 return ERR_CAST(inode);
1063         if (generation && inode->i_generation != generation) {
1064                 iput(inode);
1065                 return ERR_PTR(-ESTALE);
1066         }
1067
1068         return inode;
1069 }
1070
1071 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1072                                         int fh_len, int fh_type)
1073 {
1074         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1075                                     ext4_nfs_get_inode);
1076 }
1077
1078 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1079                                         int fh_len, int fh_type)
1080 {
1081         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1082                                     ext4_nfs_get_inode);
1083 }
1084
1085 /*
1086  * Try to release metadata pages (indirect blocks, directories) which are
1087  * mapped via the block device.  Since these pages could have journal heads
1088  * which would prevent try_to_free_buffers() from freeing them, we must use
1089  * jbd2 layer's try_to_free_buffers() function to release them.
1090  */
1091 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1092                                  gfp_t wait)
1093 {
1094         journal_t *journal = EXT4_SB(sb)->s_journal;
1095
1096         WARN_ON(PageChecked(page));
1097         if (!page_has_buffers(page))
1098                 return 0;
1099         if (journal)
1100                 return jbd2_journal_try_to_free_buffers(journal, page,
1101                                                         wait & ~__GFP_WAIT);
1102         return try_to_free_buffers(page);
1103 }
1104
1105 #ifdef CONFIG_QUOTA
1106 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1107 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1108
1109 static int ext4_write_dquot(struct dquot *dquot);
1110 static int ext4_acquire_dquot(struct dquot *dquot);
1111 static int ext4_release_dquot(struct dquot *dquot);
1112 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1113 static int ext4_write_info(struct super_block *sb, int type);
1114 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1115                          struct path *path);
1116 static int ext4_quota_on_sysfile(struct super_block *sb, int type,
1117                                  int format_id);
1118 static int ext4_quota_off(struct super_block *sb, int type);
1119 static int ext4_quota_off_sysfile(struct super_block *sb, int type);
1120 static int ext4_quota_on_mount(struct super_block *sb, int type);
1121 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1122                                size_t len, loff_t off);
1123 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1124                                 const char *data, size_t len, loff_t off);
1125 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1126                              unsigned int flags);
1127 static int ext4_enable_quotas(struct super_block *sb);
1128
1129 static const struct dquot_operations ext4_quota_operations = {
1130         .get_reserved_space = ext4_get_reserved_space,
1131         .write_dquot    = ext4_write_dquot,
1132         .acquire_dquot  = ext4_acquire_dquot,
1133         .release_dquot  = ext4_release_dquot,
1134         .mark_dirty     = ext4_mark_dquot_dirty,
1135         .write_info     = ext4_write_info,
1136         .alloc_dquot    = dquot_alloc,
1137         .destroy_dquot  = dquot_destroy,
1138 };
1139
1140 static const struct quotactl_ops ext4_qctl_operations = {
1141         .quota_on       = ext4_quota_on,
1142         .quota_off      = ext4_quota_off,
1143         .quota_sync     = dquot_quota_sync,
1144         .get_info       = dquot_get_dqinfo,
1145         .set_info       = dquot_set_dqinfo,
1146         .get_dqblk      = dquot_get_dqblk,
1147         .set_dqblk      = dquot_set_dqblk
1148 };
1149
1150 static const struct quotactl_ops ext4_qctl_sysfile_operations = {
1151         .quota_on_meta  = ext4_quota_on_sysfile,
1152         .quota_off      = ext4_quota_off_sysfile,
1153         .quota_sync     = dquot_quota_sync,
1154         .get_info       = dquot_get_dqinfo,
1155         .set_info       = dquot_set_dqinfo,
1156         .get_dqblk      = dquot_get_dqblk,
1157         .set_dqblk      = dquot_set_dqblk
1158 };
1159 #endif
1160
1161 static const struct super_operations ext4_sops = {
1162         .alloc_inode    = ext4_alloc_inode,
1163         .destroy_inode  = ext4_destroy_inode,
1164         .write_inode    = ext4_write_inode,
1165         .dirty_inode    = ext4_dirty_inode,
1166         .drop_inode     = ext4_drop_inode,
1167         .evict_inode    = ext4_evict_inode,
1168         .put_super      = ext4_put_super,
1169         .sync_fs        = ext4_sync_fs,
1170         .freeze_fs      = ext4_freeze,
1171         .unfreeze_fs    = ext4_unfreeze,
1172         .statfs         = ext4_statfs,
1173         .remount_fs     = ext4_remount,
1174         .show_options   = ext4_show_options,
1175 #ifdef CONFIG_QUOTA
1176         .quota_read     = ext4_quota_read,
1177         .quota_write    = ext4_quota_write,
1178 #endif
1179         .bdev_try_to_free_page = bdev_try_to_free_page,
1180 };
1181
1182 static const struct super_operations ext4_nojournal_sops = {
1183         .alloc_inode    = ext4_alloc_inode,
1184         .destroy_inode  = ext4_destroy_inode,
1185         .write_inode    = ext4_write_inode,
1186         .dirty_inode    = ext4_dirty_inode,
1187         .drop_inode     = ext4_drop_inode,
1188         .evict_inode    = ext4_evict_inode,
1189         .put_super      = ext4_put_super,
1190         .statfs         = ext4_statfs,
1191         .remount_fs     = ext4_remount,
1192         .show_options   = ext4_show_options,
1193 #ifdef CONFIG_QUOTA
1194         .quota_read     = ext4_quota_read,
1195         .quota_write    = ext4_quota_write,
1196 #endif
1197         .bdev_try_to_free_page = bdev_try_to_free_page,
1198 };
1199
1200 static const struct export_operations ext4_export_ops = {
1201         .fh_to_dentry = ext4_fh_to_dentry,
1202         .fh_to_parent = ext4_fh_to_parent,
1203         .get_parent = ext4_get_parent,
1204 };
1205
1206 enum {
1207         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1208         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1209         Opt_nouid32, Opt_debug, Opt_removed,
1210         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1211         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1212         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1213         Opt_journal_dev, Opt_journal_checksum, Opt_journal_async_commit,
1214         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1215         Opt_data_err_abort, Opt_data_err_ignore,
1216         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1217         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1218         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1219         Opt_usrquota, Opt_grpquota, Opt_i_version,
1220         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1221         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1222         Opt_inode_readahead_blks, Opt_journal_ioprio,
1223         Opt_dioread_nolock, Opt_dioread_lock,
1224         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1225         Opt_max_dir_size_kb,
1226 };
1227
1228 static const match_table_t tokens = {
1229         {Opt_bsd_df, "bsddf"},
1230         {Opt_minix_df, "minixdf"},
1231         {Opt_grpid, "grpid"},
1232         {Opt_grpid, "bsdgroups"},
1233         {Opt_nogrpid, "nogrpid"},
1234         {Opt_nogrpid, "sysvgroups"},
1235         {Opt_resgid, "resgid=%u"},
1236         {Opt_resuid, "resuid=%u"},
1237         {Opt_sb, "sb=%u"},
1238         {Opt_err_cont, "errors=continue"},
1239         {Opt_err_panic, "errors=panic"},
1240         {Opt_err_ro, "errors=remount-ro"},
1241         {Opt_nouid32, "nouid32"},
1242         {Opt_debug, "debug"},
1243         {Opt_removed, "oldalloc"},
1244         {Opt_removed, "orlov"},
1245         {Opt_user_xattr, "user_xattr"},
1246         {Opt_nouser_xattr, "nouser_xattr"},
1247         {Opt_acl, "acl"},
1248         {Opt_noacl, "noacl"},
1249         {Opt_noload, "norecovery"},
1250         {Opt_noload, "noload"},
1251         {Opt_removed, "nobh"},
1252         {Opt_removed, "bh"},
1253         {Opt_commit, "commit=%u"},
1254         {Opt_min_batch_time, "min_batch_time=%u"},
1255         {Opt_max_batch_time, "max_batch_time=%u"},
1256         {Opt_journal_dev, "journal_dev=%u"},
1257         {Opt_journal_checksum, "journal_checksum"},
1258         {Opt_journal_async_commit, "journal_async_commit"},
1259         {Opt_abort, "abort"},
1260         {Opt_data_journal, "data=journal"},
1261         {Opt_data_ordered, "data=ordered"},
1262         {Opt_data_writeback, "data=writeback"},
1263         {Opt_data_err_abort, "data_err=abort"},
1264         {Opt_data_err_ignore, "data_err=ignore"},
1265         {Opt_offusrjquota, "usrjquota="},
1266         {Opt_usrjquota, "usrjquota=%s"},
1267         {Opt_offgrpjquota, "grpjquota="},
1268         {Opt_grpjquota, "grpjquota=%s"},
1269         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1270         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1271         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1272         {Opt_grpquota, "grpquota"},
1273         {Opt_noquota, "noquota"},
1274         {Opt_quota, "quota"},
1275         {Opt_usrquota, "usrquota"},
1276         {Opt_barrier, "barrier=%u"},
1277         {Opt_barrier, "barrier"},
1278         {Opt_nobarrier, "nobarrier"},
1279         {Opt_i_version, "i_version"},
1280         {Opt_stripe, "stripe=%u"},
1281         {Opt_delalloc, "delalloc"},
1282         {Opt_nodelalloc, "nodelalloc"},
1283         {Opt_mblk_io_submit, "mblk_io_submit"},
1284         {Opt_nomblk_io_submit, "nomblk_io_submit"},
1285         {Opt_block_validity, "block_validity"},
1286         {Opt_noblock_validity, "noblock_validity"},
1287         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1288         {Opt_journal_ioprio, "journal_ioprio=%u"},
1289         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1290         {Opt_auto_da_alloc, "auto_da_alloc"},
1291         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1292         {Opt_dioread_nolock, "dioread_nolock"},
1293         {Opt_dioread_lock, "dioread_lock"},
1294         {Opt_discard, "discard"},
1295         {Opt_nodiscard, "nodiscard"},
1296         {Opt_init_itable, "init_itable=%u"},
1297         {Opt_init_itable, "init_itable"},
1298         {Opt_noinit_itable, "noinit_itable"},
1299         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1300         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1301         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1302         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1303         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1304         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1305         {Opt_err, NULL},
1306 };
1307
1308 static ext4_fsblk_t get_sb_block(void **data)
1309 {
1310         ext4_fsblk_t    sb_block;
1311         char            *options = (char *) *data;
1312
1313         if (!options || strncmp(options, "sb=", 3) != 0)
1314                 return 1;       /* Default location */
1315
1316         options += 3;
1317         /* TODO: use simple_strtoll with >32bit ext4 */
1318         sb_block = simple_strtoul(options, &options, 0);
1319         if (*options && *options != ',') {
1320                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1321                        (char *) *data);
1322                 return 1;
1323         }
1324         if (*options == ',')
1325                 options++;
1326         *data = (void *) options;
1327
1328         return sb_block;
1329 }
1330
1331 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1332 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1333         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1334
1335 #ifdef CONFIG_QUOTA
1336 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1337 {
1338         struct ext4_sb_info *sbi = EXT4_SB(sb);
1339         char *qname;
1340
1341         if (sb_any_quota_loaded(sb) &&
1342                 !sbi->s_qf_names[qtype]) {
1343                 ext4_msg(sb, KERN_ERR,
1344                         "Cannot change journaled "
1345                         "quota options when quota turned on");
1346                 return -1;
1347         }
1348         qname = match_strdup(args);
1349         if (!qname) {
1350                 ext4_msg(sb, KERN_ERR,
1351                         "Not enough memory for storing quotafile name");
1352                 return -1;
1353         }
1354         if (sbi->s_qf_names[qtype] &&
1355                 strcmp(sbi->s_qf_names[qtype], qname)) {
1356                 ext4_msg(sb, KERN_ERR,
1357                         "%s quota file already specified", QTYPE2NAME(qtype));
1358                 kfree(qname);
1359                 return -1;
1360         }
1361         sbi->s_qf_names[qtype] = qname;
1362         if (strchr(sbi->s_qf_names[qtype], '/')) {
1363                 ext4_msg(sb, KERN_ERR,
1364                         "quotafile must be on filesystem root");
1365                 kfree(sbi->s_qf_names[qtype]);
1366                 sbi->s_qf_names[qtype] = NULL;
1367                 return -1;
1368         }
1369         set_opt(sb, QUOTA);
1370         return 1;
1371 }
1372
1373 static int clear_qf_name(struct super_block *sb, int qtype)
1374 {
1375
1376         struct ext4_sb_info *sbi = EXT4_SB(sb);
1377
1378         if (sb_any_quota_loaded(sb) &&
1379                 sbi->s_qf_names[qtype]) {
1380                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1381                         " when quota turned on");
1382                 return -1;
1383         }
1384         /*
1385          * The space will be released later when all options are confirmed
1386          * to be correct
1387          */
1388         sbi->s_qf_names[qtype] = NULL;
1389         return 1;
1390 }
1391 #endif
1392
1393 #define MOPT_SET        0x0001
1394 #define MOPT_CLEAR      0x0002
1395 #define MOPT_NOSUPPORT  0x0004
1396 #define MOPT_EXPLICIT   0x0008
1397 #define MOPT_CLEAR_ERR  0x0010
1398 #define MOPT_GTE0       0x0020
1399 #ifdef CONFIG_QUOTA
1400 #define MOPT_Q          0
1401 #define MOPT_QFMT       0x0040
1402 #else
1403 #define MOPT_Q          MOPT_NOSUPPORT
1404 #define MOPT_QFMT       MOPT_NOSUPPORT
1405 #endif
1406 #define MOPT_DATAJ      0x0080
1407
1408 static const struct mount_opts {
1409         int     token;
1410         int     mount_opt;
1411         int     flags;
1412 } ext4_mount_opts[] = {
1413         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1414         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1415         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1416         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1417         {Opt_mblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_SET},
1418         {Opt_nomblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_CLEAR},
1419         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1420         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1421         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_SET},
1422         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_CLEAR},
1423         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1424         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1425         {Opt_delalloc, EXT4_MOUNT_DELALLOC, MOPT_SET | MOPT_EXPLICIT},
1426         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC, MOPT_CLEAR | MOPT_EXPLICIT},
1427         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM, MOPT_SET},
1428         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1429                                     EXT4_MOUNT_JOURNAL_CHECKSUM), MOPT_SET},
1430         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_SET},
1431         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1432         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1433         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1434         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_SET},
1435         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_CLEAR},
1436         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1437         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1438         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1439         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1440         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1441         {Opt_commit, 0, MOPT_GTE0},
1442         {Opt_max_batch_time, 0, MOPT_GTE0},
1443         {Opt_min_batch_time, 0, MOPT_GTE0},
1444         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1445         {Opt_init_itable, 0, MOPT_GTE0},
1446         {Opt_stripe, 0, MOPT_GTE0},
1447         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_DATAJ},
1448         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_DATAJ},
1449         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA, MOPT_DATAJ},
1450         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1451         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1452 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1453         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1454         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1455 #else
1456         {Opt_acl, 0, MOPT_NOSUPPORT},
1457         {Opt_noacl, 0, MOPT_NOSUPPORT},
1458 #endif
1459         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1460         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1461         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1462         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1463                                                         MOPT_SET | MOPT_Q},
1464         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1465                                                         MOPT_SET | MOPT_Q},
1466         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1467                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1468         {Opt_usrjquota, 0, MOPT_Q},
1469         {Opt_grpjquota, 0, MOPT_Q},
1470         {Opt_offusrjquota, 0, MOPT_Q},
1471         {Opt_offgrpjquota, 0, MOPT_Q},
1472         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1473         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1474         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1475         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1476         {Opt_err, 0, 0}
1477 };
1478
1479 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1480                             substring_t *args, unsigned long *journal_devnum,
1481                             unsigned int *journal_ioprio, int is_remount)
1482 {
1483         struct ext4_sb_info *sbi = EXT4_SB(sb);
1484         const struct mount_opts *m;
1485         kuid_t uid;
1486         kgid_t gid;
1487         int arg = 0;
1488
1489 #ifdef CONFIG_QUOTA
1490         if (token == Opt_usrjquota)
1491                 return set_qf_name(sb, USRQUOTA, &args[0]);
1492         else if (token == Opt_grpjquota)
1493                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1494         else if (token == Opt_offusrjquota)
1495                 return clear_qf_name(sb, USRQUOTA);
1496         else if (token == Opt_offgrpjquota)
1497                 return clear_qf_name(sb, GRPQUOTA);
1498 #endif
1499         if (args->from && match_int(args, &arg))
1500                 return -1;
1501         switch (token) {
1502         case Opt_noacl:
1503         case Opt_nouser_xattr:
1504                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1505                 break;
1506         case Opt_sb:
1507                 return 1;       /* handled by get_sb_block() */
1508         case Opt_removed:
1509                 ext4_msg(sb, KERN_WARNING,
1510                          "Ignoring removed %s option", opt);
1511                 return 1;
1512         case Opt_resuid:
1513                 uid = make_kuid(current_user_ns(), arg);
1514                 if (!uid_valid(uid)) {
1515                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1516                         return -1;
1517                 }
1518                 sbi->s_resuid = uid;
1519                 return 1;
1520         case Opt_resgid:
1521                 gid = make_kgid(current_user_ns(), arg);
1522                 if (!gid_valid(gid)) {
1523                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1524                         return -1;
1525                 }
1526                 sbi->s_resgid = gid;
1527                 return 1;
1528         case Opt_abort:
1529                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1530                 return 1;
1531         case Opt_i_version:
1532                 sb->s_flags |= MS_I_VERSION;
1533                 return 1;
1534         case Opt_journal_dev:
1535                 if (is_remount) {
1536                         ext4_msg(sb, KERN_ERR,
1537                                  "Cannot specify journal on remount");
1538                         return -1;
1539                 }
1540                 *journal_devnum = arg;
1541                 return 1;
1542         case Opt_journal_ioprio:
1543                 if (arg < 0 || arg > 7)
1544                         return -1;
1545                 *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1546                 return 1;
1547         }
1548
1549         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1550                 if (token != m->token)
1551                         continue;
1552                 if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1553                         return -1;
1554                 if (m->flags & MOPT_EXPLICIT)
1555                         set_opt2(sb, EXPLICIT_DELALLOC);
1556                 if (m->flags & MOPT_CLEAR_ERR)
1557                         clear_opt(sb, ERRORS_MASK);
1558                 if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1559                         ext4_msg(sb, KERN_ERR, "Cannot change quota "
1560                                  "options when quota turned on");
1561                         return -1;
1562                 }
1563
1564                 if (m->flags & MOPT_NOSUPPORT) {
1565                         ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1566                 } else if (token == Opt_commit) {
1567                         if (arg == 0)
1568                                 arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1569                         sbi->s_commit_interval = HZ * arg;
1570                 } else if (token == Opt_max_batch_time) {
1571                         if (arg == 0)
1572                                 arg = EXT4_DEF_MAX_BATCH_TIME;
1573                         sbi->s_max_batch_time = arg;
1574                 } else if (token == Opt_min_batch_time) {
1575                         sbi->s_min_batch_time = arg;
1576                 } else if (token == Opt_inode_readahead_blks) {
1577                         if (arg > (1 << 30))
1578                                 return -1;
1579                         if (arg && !is_power_of_2(arg)) {
1580                                 ext4_msg(sb, KERN_ERR,
1581                                          "EXT4-fs: inode_readahead_blks"
1582                                          " must be a power of 2");
1583                                 return -1;
1584                         }
1585                         sbi->s_inode_readahead_blks = arg;
1586                 } else if (token == Opt_init_itable) {
1587                         set_opt(sb, INIT_INODE_TABLE);
1588                         if (!args->from)
1589                                 arg = EXT4_DEF_LI_WAIT_MULT;
1590                         sbi->s_li_wait_mult = arg;
1591                 } else if (token == Opt_max_dir_size_kb) {
1592                         sbi->s_max_dir_size_kb = arg;
1593                 } else if (token == Opt_stripe) {
1594                         sbi->s_stripe = arg;
1595                 } else if (m->flags & MOPT_DATAJ) {
1596                         if (is_remount) {
1597                                 if (!sbi->s_journal)
1598                                         ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1599                                 else if (test_opt(sb, DATA_FLAGS) !=
1600                                          m->mount_opt) {
1601                                         ext4_msg(sb, KERN_ERR,
1602                                          "Cannot change data mode on remount");
1603                                         return -1;
1604                                 }
1605                         } else {
1606                                 clear_opt(sb, DATA_FLAGS);
1607                                 sbi->s_mount_opt |= m->mount_opt;
1608                         }
1609 #ifdef CONFIG_QUOTA
1610                 } else if (m->flags & MOPT_QFMT) {
1611                         if (sb_any_quota_loaded(sb) &&
1612                             sbi->s_jquota_fmt != m->mount_opt) {
1613                                 ext4_msg(sb, KERN_ERR, "Cannot "
1614                                          "change journaled quota options "
1615                                          "when quota turned on");
1616                                 return -1;
1617                         }
1618                         sbi->s_jquota_fmt = m->mount_opt;
1619 #endif
1620                 } else {
1621                         if (!args->from)
1622                                 arg = 1;
1623                         if (m->flags & MOPT_CLEAR)
1624                                 arg = !arg;
1625                         else if (unlikely(!(m->flags & MOPT_SET))) {
1626                                 ext4_msg(sb, KERN_WARNING,
1627                                          "buggy handling of option %s", opt);
1628                                 WARN_ON(1);
1629                                 return -1;
1630                         }
1631                         if (arg != 0)
1632                                 sbi->s_mount_opt |= m->mount_opt;
1633                         else
1634                                 sbi->s_mount_opt &= ~m->mount_opt;
1635                 }
1636                 return 1;
1637         }
1638         ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1639                  "or missing value", opt);
1640         return -1;
1641 }
1642
1643 static int parse_options(char *options, struct super_block *sb,
1644                          unsigned long *journal_devnum,
1645                          unsigned int *journal_ioprio,
1646                          int is_remount)
1647 {
1648         struct ext4_sb_info *sbi = EXT4_SB(sb);
1649         char *p;
1650         substring_t args[MAX_OPT_ARGS];
1651         int token;
1652
1653         if (!options)
1654                 return 1;
1655
1656         while ((p = strsep(&options, ",")) != NULL) {
1657                 if (!*p)
1658                         continue;
1659                 /*
1660                  * Initialize args struct so we know whether arg was
1661                  * found; some options take optional arguments.
1662                  */
1663                 args[0].to = args[0].from = NULL;
1664                 token = match_token(p, tokens, args);
1665                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1666                                      journal_ioprio, is_remount) < 0)
1667                         return 0;
1668         }
1669 #ifdef CONFIG_QUOTA
1670         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1671                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1672                         clear_opt(sb, USRQUOTA);
1673
1674                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1675                         clear_opt(sb, GRPQUOTA);
1676
1677                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1678                         ext4_msg(sb, KERN_ERR, "old and new quota "
1679                                         "format mixing");
1680                         return 0;
1681                 }
1682
1683                 if (!sbi->s_jquota_fmt) {
1684                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1685                                         "not specified");
1686                         return 0;
1687                 }
1688         } else {
1689                 if (sbi->s_jquota_fmt) {
1690                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1691                                         "specified with no journaling "
1692                                         "enabled");
1693                         return 0;
1694                 }
1695         }
1696 #endif
1697         if (test_opt(sb, DIOREAD_NOLOCK)) {
1698                 int blocksize =
1699                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1700
1701                 if (blocksize < PAGE_CACHE_SIZE) {
1702                         ext4_msg(sb, KERN_ERR, "can't mount with "
1703                                  "dioread_nolock if block size != PAGE_SIZE");
1704                         return 0;
1705                 }
1706         }
1707         return 1;
1708 }
1709
1710 static inline void ext4_show_quota_options(struct seq_file *seq,
1711                                            struct super_block *sb)
1712 {
1713 #if defined(CONFIG_QUOTA)
1714         struct ext4_sb_info *sbi = EXT4_SB(sb);
1715
1716         if (sbi->s_jquota_fmt) {
1717                 char *fmtname = "";
1718
1719                 switch (sbi->s_jquota_fmt) {
1720                 case QFMT_VFS_OLD:
1721                         fmtname = "vfsold";
1722                         break;
1723                 case QFMT_VFS_V0:
1724                         fmtname = "vfsv0";
1725                         break;
1726                 case QFMT_VFS_V1:
1727                         fmtname = "vfsv1";
1728                         break;
1729                 }
1730                 seq_printf(seq, ",jqfmt=%s", fmtname);
1731         }
1732
1733         if (sbi->s_qf_names[USRQUOTA])
1734                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1735
1736         if (sbi->s_qf_names[GRPQUOTA])
1737                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1738
1739         if (test_opt(sb, USRQUOTA))
1740                 seq_puts(seq, ",usrquota");
1741
1742         if (test_opt(sb, GRPQUOTA))
1743                 seq_puts(seq, ",grpquota");
1744 #endif
1745 }
1746
1747 static const char *token2str(int token)
1748 {
1749         const struct match_token *t;
1750
1751         for (t = tokens; t->token != Opt_err; t++)
1752                 if (t->token == token && !strchr(t->pattern, '='))
1753                         break;
1754         return t->pattern;
1755 }
1756
1757 /*
1758  * Show an option if
1759  *  - it's set to a non-default value OR
1760  *  - if the per-sb default is different from the global default
1761  */
1762 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1763                               int nodefs)
1764 {
1765         struct ext4_sb_info *sbi = EXT4_SB(sb);
1766         struct ext4_super_block *es = sbi->s_es;
1767         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1768         const struct mount_opts *m;
1769         char sep = nodefs ? '\n' : ',';
1770
1771 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1772 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1773
1774         if (sbi->s_sb_block != 1)
1775                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1776
1777         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1778                 int want_set = m->flags & MOPT_SET;
1779                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1780                     (m->flags & MOPT_CLEAR_ERR))
1781                         continue;
1782                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1783                         continue; /* skip if same as the default */
1784                 if ((want_set &&
1785                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1786                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1787                         continue; /* select Opt_noFoo vs Opt_Foo */
1788                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1789         }
1790
1791         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1792             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1793                 SEQ_OPTS_PRINT("resuid=%u",
1794                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1795         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1796             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1797                 SEQ_OPTS_PRINT("resgid=%u",
1798                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1799         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1800         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1801                 SEQ_OPTS_PUTS("errors=remount-ro");
1802         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1803                 SEQ_OPTS_PUTS("errors=continue");
1804         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1805                 SEQ_OPTS_PUTS("errors=panic");
1806         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1807                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1808         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1809                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1810         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1811                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1812         if (sb->s_flags & MS_I_VERSION)
1813                 SEQ_OPTS_PUTS("i_version");
1814         if (nodefs || sbi->s_stripe)
1815                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1816         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1817                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1818                         SEQ_OPTS_PUTS("data=journal");
1819                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1820                         SEQ_OPTS_PUTS("data=ordered");
1821                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1822                         SEQ_OPTS_PUTS("data=writeback");
1823         }
1824         if (nodefs ||
1825             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1826                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1827                                sbi->s_inode_readahead_blks);
1828
1829         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1830                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1831                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1832         if (nodefs || sbi->s_max_dir_size_kb)
1833                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
1834
1835         ext4_show_quota_options(seq, sb);
1836         return 0;
1837 }
1838
1839 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1840 {
1841         return _ext4_show_options(seq, root->d_sb, 0);
1842 }
1843
1844 static int options_seq_show(struct seq_file *seq, void *offset)
1845 {
1846         struct super_block *sb = seq->private;
1847         int rc;
1848
1849         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1850         rc = _ext4_show_options(seq, sb, 1);
1851         seq_puts(seq, "\n");
1852         return rc;
1853 }
1854
1855 static int options_open_fs(struct inode *inode, struct file *file)
1856 {
1857         return single_open(file, options_seq_show, PDE(inode)->data);
1858 }
1859
1860 static const struct file_operations ext4_seq_options_fops = {
1861         .owner = THIS_MODULE,
1862         .open = options_open_fs,
1863         .read = seq_read,
1864         .llseek = seq_lseek,
1865         .release = single_release,
1866 };
1867
1868 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1869                             int read_only)
1870 {
1871         struct ext4_sb_info *sbi = EXT4_SB(sb);
1872         int res = 0;
1873
1874         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1875                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1876                          "forcing read-only mode");
1877                 res = MS_RDONLY;
1878         }
1879         if (read_only)
1880                 goto done;
1881         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1882                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1883                          "running e2fsck is recommended");
1884         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1885                 ext4_msg(sb, KERN_WARNING,
1886                          "warning: mounting fs with errors, "
1887                          "running e2fsck is recommended");
1888         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1889                  le16_to_cpu(es->s_mnt_count) >=
1890                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1891                 ext4_msg(sb, KERN_WARNING,
1892                          "warning: maximal mount count reached, "
1893                          "running e2fsck is recommended");
1894         else if (le32_to_cpu(es->s_checkinterval) &&
1895                 (le32_to_cpu(es->s_lastcheck) +
1896                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1897                 ext4_msg(sb, KERN_WARNING,
1898                          "warning: checktime reached, "
1899                          "running e2fsck is recommended");
1900         if (!sbi->s_journal)
1901                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1902         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1903                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1904         le16_add_cpu(&es->s_mnt_count, 1);
1905         es->s_mtime = cpu_to_le32(get_seconds());
1906         ext4_update_dynamic_rev(sb);
1907         if (sbi->s_journal)
1908                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1909
1910         ext4_commit_super(sb, 1);
1911 done:
1912         if (test_opt(sb, DEBUG))
1913                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1914                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1915                         sb->s_blocksize,
1916                         sbi->s_groups_count,
1917                         EXT4_BLOCKS_PER_GROUP(sb),
1918                         EXT4_INODES_PER_GROUP(sb),
1919                         sbi->s_mount_opt, sbi->s_mount_opt2);
1920
1921         cleancache_init_fs(sb);
1922         return res;
1923 }
1924
1925 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
1926 {
1927         struct ext4_sb_info *sbi = EXT4_SB(sb);
1928         struct flex_groups *new_groups;
1929         int size;
1930
1931         if (!sbi->s_log_groups_per_flex)
1932                 return 0;
1933
1934         size = ext4_flex_group(sbi, ngroup - 1) + 1;
1935         if (size <= sbi->s_flex_groups_allocated)
1936                 return 0;
1937
1938         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
1939         new_groups = ext4_kvzalloc(size, GFP_KERNEL);
1940         if (!new_groups) {
1941                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
1942                          size / (int) sizeof(struct flex_groups));
1943                 return -ENOMEM;
1944         }
1945
1946         if (sbi->s_flex_groups) {
1947                 memcpy(new_groups, sbi->s_flex_groups,
1948                        (sbi->s_flex_groups_allocated *
1949                         sizeof(struct flex_groups)));
1950                 ext4_kvfree(sbi->s_flex_groups);
1951         }
1952         sbi->s_flex_groups = new_groups;
1953         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
1954         return 0;
1955 }
1956
1957 static int ext4_fill_flex_info(struct super_block *sb)
1958 {
1959         struct ext4_sb_info *sbi = EXT4_SB(sb);
1960         struct ext4_group_desc *gdp = NULL;
1961         ext4_group_t flex_group;
1962         unsigned int groups_per_flex = 0;
1963         int i, err;
1964
1965         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1966         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1967                 sbi->s_log_groups_per_flex = 0;
1968                 return 1;
1969         }
1970         groups_per_flex = 1U << sbi->s_log_groups_per_flex;
1971
1972         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
1973         if (err)
1974                 goto failed;
1975
1976         for (i = 0; i < sbi->s_groups_count; i++) {
1977                 gdp = ext4_get_group_desc(sb, i, NULL);
1978
1979                 flex_group = ext4_flex_group(sbi, i);
1980                 atomic_add(ext4_free_inodes_count(sb, gdp),
1981                            &sbi->s_flex_groups[flex_group].free_inodes);
1982                 atomic_add(ext4_free_group_clusters(sb, gdp),
1983                            &sbi->s_flex_groups[flex_group].free_clusters);
1984                 atomic_add(ext4_used_dirs_count(sb, gdp),
1985                            &sbi->s_flex_groups[flex_group].used_dirs);
1986         }
1987
1988         return 1;
1989 failed:
1990         return 0;
1991 }
1992
1993 static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1994                                    struct ext4_group_desc *gdp)
1995 {
1996         int offset;
1997         __u16 crc = 0;
1998         __le32 le_group = cpu_to_le32(block_group);
1999
2000         if ((sbi->s_es->s_feature_ro_compat &
2001              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))) {
2002                 /* Use new metadata_csum algorithm */
2003                 __u16 old_csum;
2004                 __u32 csum32;
2005
2006                 old_csum = gdp->bg_checksum;
2007                 gdp->bg_checksum = 0;
2008                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2009                                      sizeof(le_group));
2010                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
2011                                      sbi->s_desc_size);
2012                 gdp->bg_checksum = old_csum;
2013
2014                 crc = csum32 & 0xFFFF;
2015                 goto out;
2016         }
2017
2018         /* old crc16 code */
2019         offset = offsetof(struct ext4_group_desc, bg_checksum);
2020
2021         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2022         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2023         crc = crc16(crc, (__u8 *)gdp, offset);
2024         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2025         /* for checksum of struct ext4_group_desc do the rest...*/
2026         if ((sbi->s_es->s_feature_incompat &
2027              cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2028             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2029                 crc = crc16(crc, (__u8 *)gdp + offset,
2030                             le16_to_cpu(sbi->s_es->s_desc_size) -
2031                                 offset);
2032
2033 out:
2034         return cpu_to_le16(crc);
2035 }
2036
2037 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2038                                 struct ext4_group_desc *gdp)
2039 {
2040         if (ext4_has_group_desc_csum(sb) &&
2041             (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2042                                                       block_group, gdp)))
2043                 return 0;
2044
2045         return 1;
2046 }
2047
2048 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2049                               struct ext4_group_desc *gdp)
2050 {
2051         if (!ext4_has_group_desc_csum(sb))
2052                 return;
2053         gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2054 }
2055
2056 /* Called at mount-time, super-block is locked */
2057 static int ext4_check_descriptors(struct super_block *sb,
2058                                   ext4_group_t *first_not_zeroed)
2059 {
2060         struct ext4_sb_info *sbi = EXT4_SB(sb);
2061         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2062         ext4_fsblk_t last_block;
2063         ext4_fsblk_t block_bitmap;
2064         ext4_fsblk_t inode_bitmap;
2065         ext4_fsblk_t inode_table;
2066         int flexbg_flag = 0;
2067         ext4_group_t i, grp = sbi->s_groups_count;
2068
2069         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2070                 flexbg_flag = 1;
2071
2072         ext4_debug("Checking group descriptors");
2073
2074         for (i = 0; i < sbi->s_groups_count; i++) {
2075                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2076
2077                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2078                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2079                 else
2080                         last_block = first_block +
2081                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2082
2083                 if ((grp == sbi->s_groups_count) &&
2084                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2085                         grp = i;
2086
2087                 block_bitmap = ext4_block_bitmap(sb, gdp);
2088                 if (block_bitmap < first_block || block_bitmap > last_block) {
2089                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2090                                "Block bitmap for group %u not in group "
2091                                "(block %llu)!", i, block_bitmap);
2092                         return 0;
2093                 }
2094                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2095                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2096                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2097                                "Inode bitmap for group %u not in group "
2098                                "(block %llu)!", i, inode_bitmap);
2099                         return 0;
2100                 }
2101                 inode_table = ext4_inode_table(sb, gdp);
2102                 if (inode_table < first_block ||
2103                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2104                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2105                                "Inode table for group %u not in group "
2106                                "(block %llu)!", i, inode_table);
2107                         return 0;
2108                 }
2109                 ext4_lock_group(sb, i);
2110                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2111                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2112                                  "Checksum for group %u failed (%u!=%u)",
2113                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2114                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2115                         if (!(sb->s_flags & MS_RDONLY)) {
2116                                 ext4_unlock_group(sb, i);
2117                                 return 0;
2118                         }
2119                 }
2120                 ext4_unlock_group(sb, i);
2121                 if (!flexbg_flag)
2122                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2123         }
2124         if (NULL != first_not_zeroed)
2125                 *first_not_zeroed = grp;
2126
2127         ext4_free_blocks_count_set(sbi->s_es,
2128                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2129         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2130         return 1;
2131 }
2132
2133 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2134  * the superblock) which were deleted from all directories, but held open by
2135  * a process at the time of a crash.  We walk the list and try to delete these
2136  * inodes at recovery time (only with a read-write filesystem).
2137  *
2138  * In order to keep the orphan inode chain consistent during traversal (in
2139  * case of crash during recovery), we link each inode into the superblock
2140  * orphan list_head and handle it the same way as an inode deletion during
2141  * normal operation (which journals the operations for us).
2142  *
2143  * We only do an iget() and an iput() on each inode, which is very safe if we
2144  * accidentally point at an in-use or already deleted inode.  The worst that
2145  * can happen in this case is that we get a "bit already cleared" message from
2146  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2147  * e2fsck was run on this filesystem, and it must have already done the orphan
2148  * inode cleanup for us, so we can safely abort without any further action.
2149  */
2150 static void ext4_orphan_cleanup(struct super_block *sb,
2151                                 struct ext4_super_block *es)
2152 {
2153         unsigned int s_flags = sb->s_flags;
2154         int nr_orphans = 0, nr_truncates = 0;
2155 #ifdef CONFIG_QUOTA
2156         int i;
2157 #endif
2158         if (!es->s_last_orphan) {
2159                 jbd_debug(4, "no orphan inodes to clean up\n");
2160                 return;
2161         }
2162
2163         if (bdev_read_only(sb->s_bdev)) {
2164                 ext4_msg(sb, KERN_ERR, "write access "
2165                         "unavailable, skipping orphan cleanup");
2166                 return;
2167         }
2168
2169         /* Check if feature set would not allow a r/w mount */
2170         if (!ext4_feature_set_ok(sb, 0)) {
2171                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2172                          "unknown ROCOMPAT features");
2173                 return;
2174         }
2175
2176         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2177                 /* don't clear list on RO mount w/ errors */
2178                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2179                         jbd_debug(1, "Errors on filesystem, "
2180                                   "clearing orphan list.\n");
2181                         es->s_last_orphan = 0;
2182                 }
2183                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2184                 return;
2185         }
2186
2187         if (s_flags & MS_RDONLY) {
2188                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2189                 sb->s_flags &= ~MS_RDONLY;
2190         }
2191 #ifdef CONFIG_QUOTA
2192         /* Needed for iput() to work correctly and not trash data */
2193         sb->s_flags |= MS_ACTIVE;
2194         /* Turn on quotas so that they are updated correctly */
2195         for (i = 0; i < MAXQUOTAS; i++) {
2196                 if (EXT4_SB(sb)->s_qf_names[i]) {
2197                         int ret = ext4_quota_on_mount(sb, i);
2198                         if (ret < 0)
2199                                 ext4_msg(sb, KERN_ERR,
2200                                         "Cannot turn on journaled "
2201                                         "quota: error %d", ret);
2202                 }
2203         }
2204 #endif
2205
2206         while (es->s_last_orphan) {
2207                 struct inode *inode;
2208
2209                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2210                 if (IS_ERR(inode)) {
2211                         es->s_last_orphan = 0;
2212                         break;
2213                 }
2214
2215                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2216                 dquot_initialize(inode);
2217                 if (inode->i_nlink) {
2218                         ext4_msg(sb, KERN_DEBUG,
2219                                 "%s: truncating inode %lu to %lld bytes",
2220                                 __func__, inode->i_ino, inode->i_size);
2221                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2222                                   inode->i_ino, inode->i_size);
2223                         ext4_truncate(inode);
2224                         nr_truncates++;
2225                 } else {
2226                         ext4_msg(sb, KERN_DEBUG,
2227                                 "%s: deleting unreferenced inode %lu",
2228                                 __func__, inode->i_ino);
2229                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2230                                   inode->i_ino);
2231                         nr_orphans++;
2232                 }
2233                 iput(inode);  /* The delete magic happens here! */
2234         }
2235
2236 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2237
2238         if (nr_orphans)
2239                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2240                        PLURAL(nr_orphans));
2241         if (nr_truncates)
2242                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2243                        PLURAL(nr_truncates));
2244 #ifdef CONFIG_QUOTA
2245         /* Turn quotas off */
2246         for (i = 0; i < MAXQUOTAS; i++) {
2247                 if (sb_dqopt(sb)->files[i])
2248                         dquot_quota_off(sb, i);
2249         }
2250 #endif
2251         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2252 }
2253
2254 /*
2255  * Maximal extent format file size.
2256  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2257  * extent format containers, within a sector_t, and within i_blocks
2258  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2259  * so that won't be a limiting factor.
2260  *
2261  * However there is other limiting factor. We do store extents in the form
2262  * of starting block and length, hence the resulting length of the extent
2263  * covering maximum file size must fit into on-disk format containers as
2264  * well. Given that length is always by 1 unit bigger than max unit (because
2265  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2266  *
2267  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2268  */
2269 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2270 {
2271         loff_t res;
2272         loff_t upper_limit = MAX_LFS_FILESIZE;
2273
2274         /* small i_blocks in vfs inode? */
2275         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2276                 /*
2277                  * CONFIG_LBDAF is not enabled implies the inode
2278                  * i_block represent total blocks in 512 bytes
2279                  * 32 == size of vfs inode i_blocks * 8
2280                  */
2281                 upper_limit = (1LL << 32) - 1;
2282
2283                 /* total blocks in file system block size */
2284                 upper_limit >>= (blkbits - 9);
2285                 upper_limit <<= blkbits;
2286         }
2287
2288         /*
2289          * 32-bit extent-start container, ee_block. We lower the maxbytes
2290          * by one fs block, so ee_len can cover the extent of maximum file
2291          * size
2292          */
2293         res = (1LL << 32) - 1;
2294         res <<= blkbits;
2295
2296         /* Sanity check against vm- & vfs- imposed limits */
2297         if (res > upper_limit)
2298                 res = upper_limit;
2299
2300         return res;
2301 }
2302
2303 /*
2304  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2305  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2306  * We need to be 1 filesystem block less than the 2^48 sector limit.
2307  */
2308 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2309 {
2310         loff_t res = EXT4_NDIR_BLOCKS;
2311         int meta_blocks;
2312         loff_t upper_limit;
2313         /* This is calculated to be the largest file size for a dense, block
2314          * mapped file such that the file's total number of 512-byte sectors,
2315          * including data and all indirect blocks, does not exceed (2^48 - 1).
2316          *
2317          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2318          * number of 512-byte sectors of the file.
2319          */
2320
2321         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2322                 /*
2323                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2324                  * the inode i_block field represents total file blocks in
2325                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2326                  */
2327                 upper_limit = (1LL << 32) - 1;
2328
2329                 /* total blocks in file system block size */
2330                 upper_limit >>= (bits - 9);
2331
2332         } else {
2333                 /*
2334                  * We use 48 bit ext4_inode i_blocks
2335                  * With EXT4_HUGE_FILE_FL set the i_blocks
2336                  * represent total number of blocks in
2337                  * file system block size
2338                  */
2339                 upper_limit = (1LL << 48) - 1;
2340
2341         }
2342
2343         /* indirect blocks */
2344         meta_blocks = 1;
2345         /* double indirect blocks */
2346         meta_blocks += 1 + (1LL << (bits-2));
2347         /* tripple indirect blocks */
2348         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2349
2350         upper_limit -= meta_blocks;
2351         upper_limit <<= bits;
2352
2353         res += 1LL << (bits-2);
2354         res += 1LL << (2*(bits-2));
2355         res += 1LL << (3*(bits-2));
2356         res <<= bits;
2357         if (res > upper_limit)
2358                 res = upper_limit;
2359
2360         if (res > MAX_LFS_FILESIZE)
2361                 res = MAX_LFS_FILESIZE;
2362
2363         return res;
2364 }
2365
2366 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2367                                    ext4_fsblk_t logical_sb_block, int nr)
2368 {
2369         struct ext4_sb_info *sbi = EXT4_SB(sb);
2370         ext4_group_t bg, first_meta_bg;
2371         int has_super = 0;
2372
2373         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2374
2375         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2376             nr < first_meta_bg)
2377                 return logical_sb_block + nr + 1;
2378         bg = sbi->s_desc_per_block * nr;
2379         if (ext4_bg_has_super(sb, bg))
2380                 has_super = 1;
2381
2382         return (has_super + ext4_group_first_block_no(sb, bg));
2383 }
2384
2385 /**
2386  * ext4_get_stripe_size: Get the stripe size.
2387  * @sbi: In memory super block info
2388  *
2389  * If we have specified it via mount option, then
2390  * use the mount option value. If the value specified at mount time is
2391  * greater than the blocks per group use the super block value.
2392  * If the super block value is greater than blocks per group return 0.
2393  * Allocator needs it be less than blocks per group.
2394  *
2395  */
2396 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2397 {
2398         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2399         unsigned long stripe_width =
2400                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2401         int ret;
2402
2403         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2404                 ret = sbi->s_stripe;
2405         else if (stripe_width <= sbi->s_blocks_per_group)
2406                 ret = stripe_width;
2407         else if (stride <= sbi->s_blocks_per_group)
2408                 ret = stride;
2409         else
2410                 ret = 0;
2411
2412         /*
2413          * If the stripe width is 1, this makes no sense and
2414          * we set it to 0 to turn off stripe handling code.
2415          */
2416         if (ret <= 1)
2417                 ret = 0;
2418
2419         return ret;
2420 }
2421
2422 /* sysfs supprt */
2423
2424 struct ext4_attr {
2425         struct attribute attr;
2426         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2427         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2428                          const char *, size_t);
2429         int offset;
2430 };
2431
2432 static int parse_strtoul(const char *buf,
2433                 unsigned long max, unsigned long *value)
2434 {
2435         char *endp;
2436
2437         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2438         endp = skip_spaces(endp);
2439         if (*endp || *value > max)
2440                 return -EINVAL;
2441
2442         return 0;
2443 }
2444
2445 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2446                                               struct ext4_sb_info *sbi,
2447                                               char *buf)
2448 {
2449         return snprintf(buf, PAGE_SIZE, "%llu\n",
2450                 (s64) EXT4_C2B(sbi,
2451                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2452 }
2453
2454 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2455                                          struct ext4_sb_info *sbi, char *buf)
2456 {
2457         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2458
2459         if (!sb->s_bdev->bd_part)
2460                 return snprintf(buf, PAGE_SIZE, "0\n");
2461         return snprintf(buf, PAGE_SIZE, "%lu\n",
2462                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2463                          sbi->s_sectors_written_start) >> 1);
2464 }
2465
2466 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2467                                           struct ext4_sb_info *sbi, char *buf)
2468 {
2469         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2470
2471         if (!sb->s_bdev->bd_part)
2472                 return snprintf(buf, PAGE_SIZE, "0\n");
2473         return snprintf(buf, PAGE_SIZE, "%llu\n",
2474                         (unsigned long long)(sbi->s_kbytes_written +
2475                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2476                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2477 }
2478
2479 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2480                                           struct ext4_sb_info *sbi,
2481                                           const char *buf, size_t count)
2482 {
2483         unsigned long t;
2484
2485         if (parse_strtoul(buf, 0x40000000, &t))
2486                 return -EINVAL;
2487
2488         if (t && !is_power_of_2(t))
2489                 return -EINVAL;
2490
2491         sbi->s_inode_readahead_blks = t;
2492         return count;
2493 }
2494
2495 static ssize_t sbi_ui_show(struct ext4_attr *a,
2496                            struct ext4_sb_info *sbi, char *buf)
2497 {
2498         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2499
2500         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2501 }
2502
2503 static ssize_t sbi_ui_store(struct ext4_attr *a,
2504                             struct ext4_sb_info *sbi,
2505                             const char *buf, size_t count)
2506 {
2507         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2508         unsigned long t;
2509
2510         if (parse_strtoul(buf, 0xffffffff, &t))
2511                 return -EINVAL;
2512         *ui = t;
2513         return count;
2514 }
2515
2516 static ssize_t trigger_test_error(struct ext4_attr *a,
2517                                   struct ext4_sb_info *sbi,
2518                                   const char *buf, size_t count)
2519 {
2520         int len = count;
2521
2522         if (!capable(CAP_SYS_ADMIN))
2523                 return -EPERM;
2524
2525         if (len && buf[len-1] == '\n')
2526                 len--;
2527
2528         if (len)
2529                 ext4_error(sbi->s_sb, "%.*s", len, buf);
2530         return count;
2531 }
2532
2533 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2534 static struct ext4_attr ext4_attr_##_name = {                   \
2535         .attr = {.name = __stringify(_name), .mode = _mode },   \
2536         .show   = _show,                                        \
2537         .store  = _store,                                       \
2538         .offset = offsetof(struct ext4_sb_info, _elname),       \
2539 }
2540 #define EXT4_ATTR(name, mode, show, store) \
2541 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2542
2543 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2544 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2545 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2546 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2547         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2548 #define ATTR_LIST(name) &ext4_attr_##name.attr
2549
2550 EXT4_RO_ATTR(delayed_allocation_blocks);
2551 EXT4_RO_ATTR(session_write_kbytes);
2552 EXT4_RO_ATTR(lifetime_write_kbytes);
2553 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2554                  inode_readahead_blks_store, s_inode_readahead_blks);
2555 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2556 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2557 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2558 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2559 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2560 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2561 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2562 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2563 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
2564 EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
2565
2566 static struct attribute *ext4_attrs[] = {
2567         ATTR_LIST(delayed_allocation_blocks),
2568         ATTR_LIST(session_write_kbytes),
2569         ATTR_LIST(lifetime_write_kbytes),
2570         ATTR_LIST(inode_readahead_blks),
2571         ATTR_LIST(inode_goal),
2572         ATTR_LIST(mb_stats),
2573         ATTR_LIST(mb_max_to_scan),
2574         ATTR_LIST(mb_min_to_scan),
2575         ATTR_LIST(mb_order2_req),
2576         ATTR_LIST(mb_stream_req),
2577         ATTR_LIST(mb_group_prealloc),
2578         ATTR_LIST(max_writeback_mb_bump),
2579         ATTR_LIST(extent_max_zeroout_kb),
2580         ATTR_LIST(trigger_fs_error),
2581         NULL,
2582 };
2583
2584 /* Features this copy of ext4 supports */
2585 EXT4_INFO_ATTR(lazy_itable_init);
2586 EXT4_INFO_ATTR(batched_discard);
2587 EXT4_INFO_ATTR(meta_bg_resize);
2588
2589 static struct attribute *ext4_feat_attrs[] = {
2590         ATTR_LIST(lazy_itable_init),
2591         ATTR_LIST(batched_discard),
2592         ATTR_LIST(meta_bg_resize),
2593         NULL,
2594 };
2595
2596 static ssize_t ext4_attr_show(struct kobject *kobj,
2597                               struct attribute *attr, char *buf)
2598 {
2599         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2600                                                 s_kobj);
2601         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2602
2603         return a->show ? a->show(a, sbi, buf) : 0;
2604 }
2605
2606 static ssize_t ext4_attr_store(struct kobject *kobj,
2607                                struct attribute *attr,
2608                                const char *buf, size_t len)
2609 {
2610         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2611                                                 s_kobj);
2612         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2613
2614         return a->store ? a->store(a, sbi, buf, len) : 0;
2615 }
2616
2617 static void ext4_sb_release(struct kobject *kobj)
2618 {
2619         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2620                                                 s_kobj);
2621         complete(&sbi->s_kobj_unregister);
2622 }
2623
2624 static const struct sysfs_ops ext4_attr_ops = {
2625         .show   = ext4_attr_show,
2626         .store  = ext4_attr_store,
2627 };
2628
2629 static struct kobj_type ext4_ktype = {
2630         .default_attrs  = ext4_attrs,
2631         .sysfs_ops      = &ext4_attr_ops,
2632         .release        = ext4_sb_release,
2633 };
2634
2635 static void ext4_feat_release(struct kobject *kobj)
2636 {
2637         complete(&ext4_feat->f_kobj_unregister);
2638 }
2639
2640 static struct kobj_type ext4_feat_ktype = {
2641         .default_attrs  = ext4_feat_attrs,
2642         .sysfs_ops      = &ext4_attr_ops,
2643         .release        = ext4_feat_release,
2644 };
2645
2646 /*
2647  * Check whether this filesystem can be mounted based on
2648  * the features present and the RDONLY/RDWR mount requested.
2649  * Returns 1 if this filesystem can be mounted as requested,
2650  * 0 if it cannot be.
2651  */
2652 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2653 {
2654         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2655                 ext4_msg(sb, KERN_ERR,
2656                         "Couldn't mount because of "
2657                         "unsupported optional features (%x)",
2658                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2659                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2660                 return 0;
2661         }
2662
2663         if (readonly)
2664                 return 1;
2665
2666         /* Check that feature set is OK for a read-write mount */
2667         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2668                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2669                          "unsupported optional features (%x)",
2670                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2671                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2672                 return 0;
2673         }
2674         /*
2675          * Large file size enabled file system can only be mounted
2676          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2677          */
2678         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2679                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2680                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2681                                  "cannot be mounted RDWR without "
2682                                  "CONFIG_LBDAF");
2683                         return 0;
2684                 }
2685         }
2686         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2687             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2688                 ext4_msg(sb, KERN_ERR,
2689                          "Can't support bigalloc feature without "
2690                          "extents feature\n");
2691                 return 0;
2692         }
2693
2694 #ifndef CONFIG_QUOTA
2695         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
2696             !readonly) {
2697                 ext4_msg(sb, KERN_ERR,
2698                          "Filesystem with quota feature cannot be mounted RDWR "
2699                          "without CONFIG_QUOTA");
2700                 return 0;
2701         }
2702 #endif  /* CONFIG_QUOTA */
2703         return 1;
2704 }
2705
2706 /*
2707  * This function is called once a day if we have errors logged
2708  * on the file system
2709  */
2710 static void print_daily_error_info(unsigned long arg)
2711 {
2712         struct super_block *sb = (struct super_block *) arg;
2713         struct ext4_sb_info *sbi;
2714         struct ext4_super_block *es;
2715
2716         sbi = EXT4_SB(sb);
2717         es = sbi->s_es;
2718
2719         if (es->s_error_count)
2720                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2721                          le32_to_cpu(es->s_error_count));
2722         if (es->s_first_error_time) {
2723                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2724                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2725                        (int) sizeof(es->s_first_error_func),
2726                        es->s_first_error_func,
2727                        le32_to_cpu(es->s_first_error_line));
2728                 if (es->s_first_error_ino)
2729                         printk(": inode %u",
2730                                le32_to_cpu(es->s_first_error_ino));
2731                 if (es->s_first_error_block)
2732                         printk(": block %llu", (unsigned long long)
2733                                le64_to_cpu(es->s_first_error_block));
2734                 printk("\n");
2735         }
2736         if (es->s_last_error_time) {
2737                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2738                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2739                        (int) sizeof(es->s_last_error_func),
2740                        es->s_last_error_func,
2741                        le32_to_cpu(es->s_last_error_line));
2742                 if (es->s_last_error_ino)
2743                         printk(": inode %u",
2744                                le32_to_cpu(es->s_last_error_ino));
2745                 if (es->s_last_error_block)
2746                         printk(": block %llu", (unsigned long long)
2747                                le64_to_cpu(es->s_last_error_block));
2748                 printk("\n");
2749         }
2750         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2751 }
2752
2753 /* Find next suitable group and run ext4_init_inode_table */
2754 static int ext4_run_li_request(struct ext4_li_request *elr)
2755 {
2756         struct ext4_group_desc *gdp = NULL;
2757         ext4_group_t group, ngroups;
2758         struct super_block *sb;
2759         unsigned long timeout = 0;
2760         int ret = 0;
2761
2762         sb = elr->lr_super;
2763         ngroups = EXT4_SB(sb)->s_groups_count;
2764
2765         sb_start_write(sb);
2766         for (group = elr->lr_next_group; group < ngroups; group++) {
2767                 gdp = ext4_get_group_desc(sb, group, NULL);
2768                 if (!gdp) {
2769                         ret = 1;
2770                         break;
2771                 }
2772
2773                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2774                         break;
2775         }
2776
2777         if (group == ngroups)
2778                 ret = 1;
2779
2780         if (!ret) {
2781                 timeout = jiffies;
2782                 ret = ext4_init_inode_table(sb, group,
2783                                             elr->lr_timeout ? 0 : 1);
2784                 if (elr->lr_timeout == 0) {
2785                         timeout = (jiffies - timeout) *
2786                                   elr->lr_sbi->s_li_wait_mult;
2787                         elr->lr_timeout = timeout;
2788                 }
2789                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2790                 elr->lr_next_group = group + 1;
2791         }
2792         sb_end_write(sb);
2793
2794         return ret;
2795 }
2796
2797 /*
2798  * Remove lr_request from the list_request and free the
2799  * request structure. Should be called with li_list_mtx held
2800  */
2801 static void ext4_remove_li_request(struct ext4_li_request *elr)
2802 {
2803         struct ext4_sb_info *sbi;
2804
2805         if (!elr)
2806                 return;
2807
2808         sbi = elr->lr_sbi;
2809
2810         list_del(&elr->lr_request);
2811         sbi->s_li_request = NULL;
2812         kfree(elr);
2813 }
2814
2815 static void ext4_unregister_li_request(struct super_block *sb)
2816 {
2817         mutex_lock(&ext4_li_mtx);
2818         if (!ext4_li_info) {
2819                 mutex_unlock(&ext4_li_mtx);
2820                 return;
2821         }
2822
2823         mutex_lock(&ext4_li_info->li_list_mtx);
2824         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2825         mutex_unlock(&ext4_li_info->li_list_mtx);
2826         mutex_unlock(&ext4_li_mtx);
2827 }
2828
2829 static struct task_struct *ext4_lazyinit_task;
2830
2831 /*
2832  * This is the function where ext4lazyinit thread lives. It walks
2833  * through the request list searching for next scheduled filesystem.
2834  * When such a fs is found, run the lazy initialization request
2835  * (ext4_rn_li_request) and keep track of the time spend in this
2836  * function. Based on that time we compute next schedule time of
2837  * the request. When walking through the list is complete, compute
2838  * next waking time and put itself into sleep.
2839  */
2840 static int ext4_lazyinit_thread(void *arg)
2841 {
2842         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2843         struct list_head *pos, *n;
2844         struct ext4_li_request *elr;
2845         unsigned long next_wakeup, cur;
2846
2847         BUG_ON(NULL == eli);
2848
2849 cont_thread:
2850         while (true) {
2851                 next_wakeup = MAX_JIFFY_OFFSET;
2852
2853                 mutex_lock(&eli->li_list_mtx);
2854                 if (list_empty(&eli->li_request_list)) {
2855                         mutex_unlock(&eli->li_list_mtx);
2856                         goto exit_thread;
2857                 }
2858
2859                 list_for_each_safe(pos, n, &eli->li_request_list) {
2860                         elr = list_entry(pos, struct ext4_li_request,
2861                                          lr_request);
2862
2863                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2864                                 if (ext4_run_li_request(elr) != 0) {
2865                                         /* error, remove the lazy_init job */
2866                                         ext4_remove_li_request(elr);
2867                                         continue;
2868                                 }
2869                         }
2870
2871                         if (time_before(elr->lr_next_sched, next_wakeup))
2872                                 next_wakeup = elr->lr_next_sched;
2873                 }
2874                 mutex_unlock(&eli->li_list_mtx);
2875
2876                 try_to_freeze();
2877
2878                 cur = jiffies;
2879                 if ((time_after_eq(cur, next_wakeup)) ||
2880                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2881                         cond_resched();
2882                         continue;
2883                 }
2884
2885                 schedule_timeout_interruptible(next_wakeup - cur);
2886
2887                 if (kthread_should_stop()) {
2888                         ext4_clear_request_list();
2889                         goto exit_thread;
2890                 }
2891         }
2892
2893 exit_thread:
2894         /*
2895          * It looks like the request list is empty, but we need
2896          * to check it under the li_list_mtx lock, to prevent any
2897          * additions into it, and of course we should lock ext4_li_mtx
2898          * to atomically free the list and ext4_li_info, because at
2899          * this point another ext4 filesystem could be registering
2900          * new one.
2901          */
2902         mutex_lock(&ext4_li_mtx);
2903         mutex_lock(&eli->li_list_mtx);
2904         if (!list_empty(&eli->li_request_list)) {
2905                 mutex_unlock(&eli->li_list_mtx);
2906                 mutex_unlock(&ext4_li_mtx);
2907                 goto cont_thread;
2908         }
2909         mutex_unlock(&eli->li_list_mtx);
2910         kfree(ext4_li_info);
2911         ext4_li_info = NULL;
2912         mutex_unlock(&ext4_li_mtx);
2913
2914         return 0;
2915 }
2916
2917 static void ext4_clear_request_list(void)
2918 {
2919         struct list_head *pos, *n;
2920         struct ext4_li_request *elr;
2921
2922         mutex_lock(&ext4_li_info->li_list_mtx);
2923         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2924                 elr = list_entry(pos, struct ext4_li_request,
2925                                  lr_request);
2926                 ext4_remove_li_request(elr);
2927         }
2928         mutex_unlock(&ext4_li_info->li_list_mtx);
2929 }
2930
2931 static int ext4_run_lazyinit_thread(void)
2932 {
2933         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2934                                          ext4_li_info, "ext4lazyinit");
2935         if (IS_ERR(ext4_lazyinit_task)) {
2936                 int err = PTR_ERR(ext4_lazyinit_task);
2937                 ext4_clear_request_list();
2938                 kfree(ext4_li_info);
2939                 ext4_li_info = NULL;
2940                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2941                                  "initialization thread\n",
2942                                  err);
2943                 return err;
2944         }
2945         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2946         return 0;
2947 }
2948
2949 /*
2950  * Check whether it make sense to run itable init. thread or not.
2951  * If there is at least one uninitialized inode table, return
2952  * corresponding group number, else the loop goes through all
2953  * groups and return total number of groups.
2954  */
2955 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2956 {
2957         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2958         struct ext4_group_desc *gdp = NULL;
2959
2960         for (group = 0; group < ngroups; group++) {
2961                 gdp = ext4_get_group_desc(sb, group, NULL);
2962                 if (!gdp)
2963                         continue;
2964
2965                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2966                         break;
2967         }
2968
2969         return group;
2970 }
2971
2972 static int ext4_li_info_new(void)
2973 {
2974         struct ext4_lazy_init *eli = NULL;
2975
2976         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2977         if (!eli)
2978                 return -ENOMEM;
2979
2980         INIT_LIST_HEAD(&eli->li_request_list);
2981         mutex_init(&eli->li_list_mtx);
2982
2983         eli->li_state |= EXT4_LAZYINIT_QUIT;
2984
2985         ext4_li_info = eli;
2986
2987         return 0;
2988 }
2989
2990 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2991                                             ext4_group_t start)
2992 {
2993         struct ext4_sb_info *sbi = EXT4_SB(sb);
2994         struct ext4_li_request *elr;
2995         unsigned long rnd;
2996
2997         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2998         if (!elr)
2999                 return NULL;
3000
3001         elr->lr_super = sb;
3002         elr->lr_sbi = sbi;
3003         elr->lr_next_group = start;
3004
3005         /*
3006          * Randomize first schedule time of the request to
3007          * spread the inode table initialization requests
3008          * better.
3009          */
3010         get_random_bytes(&rnd, sizeof(rnd));
3011         elr->lr_next_sched = jiffies + (unsigned long)rnd %
3012                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
3013
3014         return elr;
3015 }
3016
3017 static int ext4_register_li_request(struct super_block *sb,
3018                                     ext4_group_t first_not_zeroed)
3019 {
3020         struct ext4_sb_info *sbi = EXT4_SB(sb);
3021         struct ext4_li_request *elr;
3022         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3023         int ret = 0;
3024
3025         if (sbi->s_li_request != NULL) {
3026                 /*
3027                  * Reset timeout so it can be computed again, because
3028                  * s_li_wait_mult might have changed.
3029                  */
3030                 sbi->s_li_request->lr_timeout = 0;
3031                 return 0;
3032         }
3033
3034         if (first_not_zeroed == ngroups ||
3035             (sb->s_flags & MS_RDONLY) ||
3036             !test_opt(sb, INIT_INODE_TABLE))
3037                 return 0;
3038
3039         elr = ext4_li_request_new(sb, first_not_zeroed);
3040         if (!elr)
3041                 return -ENOMEM;
3042
3043         mutex_lock(&ext4_li_mtx);
3044
3045         if (NULL == ext4_li_info) {
3046                 ret = ext4_li_info_new();
3047                 if (ret)
3048                         goto out;
3049         }
3050
3051         mutex_lock(&ext4_li_info->li_list_mtx);
3052         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3053         mutex_unlock(&ext4_li_info->li_list_mtx);
3054
3055         sbi->s_li_request = elr;
3056         /*
3057          * set elr to NULL here since it has been inserted to
3058          * the request_list and the removal and free of it is
3059          * handled by ext4_clear_request_list from now on.
3060          */
3061         elr = NULL;
3062
3063         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3064                 ret = ext4_run_lazyinit_thread();
3065                 if (ret)
3066                         goto out;
3067         }
3068 out:
3069         mutex_unlock(&ext4_li_mtx);
3070         if (ret)
3071                 kfree(elr);
3072         return ret;
3073 }
3074
3075 /*
3076  * We do not need to lock anything since this is called on
3077  * module unload.
3078  */
3079 static void ext4_destroy_lazyinit_thread(void)
3080 {
3081         /*
3082          * If thread exited earlier
3083          * there's nothing to be done.
3084          */
3085         if (!ext4_li_info || !ext4_lazyinit_task)
3086                 return;
3087
3088         kthread_stop(ext4_lazyinit_task);
3089 }
3090
3091 static int set_journal_csum_feature_set(struct super_block *sb)
3092 {
3093         int ret = 1;
3094         int compat, incompat;
3095         struct ext4_sb_info *sbi = EXT4_SB(sb);
3096
3097         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3098                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3099                 /* journal checksum v2 */
3100                 compat = 0;
3101                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V2;
3102         } else {
3103                 /* journal checksum v1 */
3104                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3105                 incompat = 0;
3106         }
3107
3108         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3109                 ret = jbd2_journal_set_features(sbi->s_journal,
3110                                 compat, 0,
3111                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3112                                 incompat);
3113         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3114                 ret = jbd2_journal_set_features(sbi->s_journal,
3115                                 compat, 0,
3116                                 incompat);
3117                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3118                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3119         } else {
3120                 jbd2_journal_clear_features(sbi->s_journal,
3121                                 JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3122                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3123                                 JBD2_FEATURE_INCOMPAT_CSUM_V2);
3124         }
3125
3126         return ret;
3127 }
3128
3129 /*
3130  * Note: calculating the overhead so we can be compatible with
3131  * historical BSD practice is quite difficult in the face of
3132  * clusters/bigalloc.  This is because multiple metadata blocks from
3133  * different block group can end up in the same allocation cluster.
3134  * Calculating the exact overhead in the face of clustered allocation
3135  * requires either O(all block bitmaps) in memory or O(number of block
3136  * groups**2) in time.  We will still calculate the superblock for
3137  * older file systems --- and if we come across with a bigalloc file
3138  * system with zero in s_overhead_clusters the estimate will be close to
3139  * correct especially for very large cluster sizes --- but for newer
3140  * file systems, it's better to calculate this figure once at mkfs
3141  * time, and store it in the superblock.  If the superblock value is
3142  * present (even for non-bigalloc file systems), we will use it.
3143  */
3144 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3145                           char *buf)
3146 {
3147         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3148         struct ext4_group_desc  *gdp;
3149         ext4_fsblk_t            first_block, last_block, b;
3150         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3151         int                     s, j, count = 0;
3152
3153         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC))
3154                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3155                         sbi->s_itb_per_group + 2);
3156
3157         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3158                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3159         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3160         for (i = 0; i < ngroups; i++) {
3161                 gdp = ext4_get_group_desc(sb, i, NULL);
3162                 b = ext4_block_bitmap(sb, gdp);
3163                 if (b >= first_block && b <= last_block) {
3164                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3165                         count++;
3166                 }
3167                 b = ext4_inode_bitmap(sb, gdp);
3168                 if (b >= first_block && b <= last_block) {
3169                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3170                         count++;
3171                 }
3172                 b = ext4_inode_table(sb, gdp);
3173                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3174                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3175                                 int c = EXT4_B2C(sbi, b - first_block);
3176                                 ext4_set_bit(c, buf);
3177                                 count++;
3178                         }
3179                 if (i != grp)
3180                         continue;
3181                 s = 0;
3182                 if (ext4_bg_has_super(sb, grp)) {
3183                         ext4_set_bit(s++, buf);
3184                         count++;
3185                 }
3186                 for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) {
3187                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3188                         count++;
3189                 }
3190         }
3191         if (!count)
3192                 return 0;
3193         return EXT4_CLUSTERS_PER_GROUP(sb) -
3194                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3195 }
3196
3197 /*
3198  * Compute the overhead and stash it in sbi->s_overhead
3199  */
3200 int ext4_calculate_overhead(struct super_block *sb)
3201 {
3202         struct ext4_sb_info *sbi = EXT4_SB(sb);
3203         struct ext4_super_block *es = sbi->s_es;
3204         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3205         ext4_fsblk_t overhead = 0;
3206         char *buf = (char *) get_zeroed_page(GFP_KERNEL);
3207
3208         if (!buf)
3209                 return -ENOMEM;
3210
3211         /*
3212          * Compute the overhead (FS structures).  This is constant
3213          * for a given filesystem unless the number of block groups
3214          * changes so we cache the previous value until it does.
3215          */
3216
3217         /*
3218          * All of the blocks before first_data_block are overhead
3219          */
3220         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3221
3222         /*
3223          * Add the overhead found in each block group
3224          */
3225         for (i = 0; i < ngroups; i++) {
3226                 int blks;
3227
3228                 blks = count_overhead(sb, i, buf);
3229                 overhead += blks;
3230                 if (blks)
3231                         memset(buf, 0, PAGE_SIZE);
3232                 cond_resched();
3233         }
3234         /* Add the journal blocks as well */
3235         if (sbi->s_journal)
3236                 overhead += EXT4_B2C(sbi, sbi->s_journal->j_maxlen);
3237
3238         sbi->s_overhead = overhead;
3239         smp_wmb();
3240         free_page((unsigned long) buf);
3241         return 0;
3242 }
3243
3244 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3245 {
3246         char *orig_data = kstrdup(data, GFP_KERNEL);
3247         struct buffer_head *bh;
3248         struct ext4_super_block *es = NULL;
3249         struct ext4_sb_info *sbi;
3250         ext4_fsblk_t block;
3251         ext4_fsblk_t sb_block = get_sb_block(&data);
3252         ext4_fsblk_t logical_sb_block;
3253         unsigned long offset = 0;
3254         unsigned long journal_devnum = 0;
3255         unsigned long def_mount_opts;
3256         struct inode *root;
3257         char *cp;
3258         const char *descr;
3259         int ret = -ENOMEM;
3260         int blocksize, clustersize;
3261         unsigned int db_count;
3262         unsigned int i;
3263         int needs_recovery, has_huge_files, has_bigalloc;
3264         __u64 blocks_count;
3265         int err = 0;
3266         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3267         ext4_group_t first_not_zeroed;
3268
3269         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3270         if (!sbi)
3271                 goto out_free_orig;
3272
3273         sbi->s_blockgroup_lock =
3274                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3275         if (!sbi->s_blockgroup_lock) {
3276                 kfree(sbi);
3277                 goto out_free_orig;
3278         }
3279         sb->s_fs_info = sbi;
3280         sbi->s_sb = sb;
3281         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3282         sbi->s_sb_block = sb_block;
3283         if (sb->s_bdev->bd_part)
3284                 sbi->s_sectors_written_start =
3285                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3286
3287         /* Cleanup superblock name */
3288         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
3289                 *cp = '!';
3290
3291         /* -EINVAL is default */
3292         ret = -EINVAL;
3293         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3294         if (!blocksize) {
3295                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3296                 goto out_fail;
3297         }
3298
3299         /*
3300          * The ext4 superblock will not be buffer aligned for other than 1kB
3301          * block sizes.  We need to calculate the offset from buffer start.
3302          */
3303         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3304                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3305                 offset = do_div(logical_sb_block, blocksize);
3306         } else {
3307                 logical_sb_block = sb_block;
3308         }
3309
3310         if (!(bh = sb_bread(sb, logical_sb_block))) {
3311                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3312                 goto out_fail;
3313         }
3314         /*
3315          * Note: s_es must be initialized as soon as possible because
3316          *       some ext4 macro-instructions depend on its value
3317          */
3318         es = (struct ext4_super_block *) (bh->b_data + offset);
3319         sbi->s_es = es;
3320         sb->s_magic = le16_to_cpu(es->s_magic);
3321         if (sb->s_magic != EXT4_SUPER_MAGIC)
3322                 goto cantfind_ext4;
3323         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3324
3325         /* Warn if metadata_csum and gdt_csum are both set. */
3326         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3327                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
3328             EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_GDT_CSUM))
3329                 ext4_warning(sb, KERN_INFO "metadata_csum and uninit_bg are "
3330                              "redundant flags; please run fsck.");
3331
3332         /* Check for a known checksum algorithm */
3333         if (!ext4_verify_csum_type(sb, es)) {
3334                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3335                          "unknown checksum algorithm.");
3336                 silent = 1;
3337                 goto cantfind_ext4;
3338         }
3339
3340         /* Load the checksum driver */
3341         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3342                                        EXT4_FEATURE_RO_COMPAT_METADATA_CSUM)) {
3343                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3344                 if (IS_ERR(sbi->s_chksum_driver)) {
3345                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3346                         ret = PTR_ERR(sbi->s_chksum_driver);
3347                         sbi->s_chksum_driver = NULL;
3348                         goto failed_mount;
3349                 }
3350         }
3351
3352         /* Check superblock checksum */
3353         if (!ext4_superblock_csum_verify(sb, es)) {
3354                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3355                          "invalid superblock checksum.  Run e2fsck?");
3356                 silent = 1;
3357                 goto cantfind_ext4;
3358         }
3359
3360         /* Precompute checksum seed for all metadata */
3361         if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
3362                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
3363                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3364                                                sizeof(es->s_uuid));
3365
3366         /* Set defaults before we parse the mount options */
3367         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3368         set_opt(sb, INIT_INODE_TABLE);
3369         if (def_mount_opts & EXT4_DEFM_DEBUG)
3370                 set_opt(sb, DEBUG);
3371         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3372                 set_opt(sb, GRPID);
3373         if (def_mount_opts & EXT4_DEFM_UID16)
3374                 set_opt(sb, NO_UID32);
3375         /* xattr user namespace & acls are now defaulted on */
3376         set_opt(sb, XATTR_USER);
3377 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3378         set_opt(sb, POSIX_ACL);
3379 #endif
3380         set_opt(sb, MBLK_IO_SUBMIT);
3381         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3382                 set_opt(sb, JOURNAL_DATA);
3383         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3384                 set_opt(sb, ORDERED_DATA);
3385         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3386                 set_opt(sb, WRITEBACK_DATA);
3387
3388         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3389                 set_opt(sb, ERRORS_PANIC);
3390         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3391                 set_opt(sb, ERRORS_CONT);
3392         else
3393                 set_opt(sb, ERRORS_RO);
3394         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3395                 set_opt(sb, BLOCK_VALIDITY);
3396         if (def_mount_opts & EXT4_DEFM_DISCARD)
3397                 set_opt(sb, DISCARD);
3398
3399         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3400         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3401         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3402         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3403         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3404
3405         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3406                 set_opt(sb, BARRIER);
3407
3408         /*
3409          * enable delayed allocation by default
3410          * Use -o nodelalloc to turn it off
3411          */
3412         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3413             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3414                 set_opt(sb, DELALLOC);
3415
3416         /*
3417          * set default s_li_wait_mult for lazyinit, for the case there is
3418          * no mount option specified.
3419          */
3420         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3421
3422         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3423                            &journal_devnum, &journal_ioprio, 0)) {
3424                 ext4_msg(sb, KERN_WARNING,
3425                          "failed to parse options in superblock: %s",
3426                          sbi->s_es->s_mount_opts);
3427         }
3428         sbi->s_def_mount_opt = sbi->s_mount_opt;
3429         if (!parse_options((char *) data, sb, &journal_devnum,
3430                            &journal_ioprio, 0))
3431                 goto failed_mount;
3432
3433         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3434                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3435                             "with data=journal disables delayed "
3436                             "allocation and O_DIRECT support!\n");
3437                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3438                         ext4_msg(sb, KERN_ERR, "can't mount with "
3439                                  "both data=journal and delalloc");
3440                         goto failed_mount;
3441                 }
3442                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3443                         ext4_msg(sb, KERN_ERR, "can't mount with "
3444                                  "both data=journal and delalloc");
3445                         goto failed_mount;
3446                 }
3447                 if (test_opt(sb, DELALLOC))
3448                         clear_opt(sb, DELALLOC);
3449         }
3450
3451         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3452                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3453
3454         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3455             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3456              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3457              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3458                 ext4_msg(sb, KERN_WARNING,
3459                        "feature flags set on rev 0 fs, "
3460                        "running e2fsck is recommended");
3461
3462         if (IS_EXT2_SB(sb)) {
3463                 if (ext2_feature_set_ok(sb))
3464                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3465                                  "using the ext4 subsystem");
3466                 else {
3467                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3468                                  "to feature incompatibilities");
3469                         goto failed_mount;
3470                 }
3471         }
3472
3473         if (IS_EXT3_SB(sb)) {
3474                 if (ext3_feature_set_ok(sb))
3475                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3476                                  "using the ext4 subsystem");
3477                 else {
3478                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3479                                  "to feature incompatibilities");
3480                         goto failed_mount;
3481                 }
3482         }
3483
3484         /*
3485          * Check feature flags regardless of the revision level, since we
3486          * previously didn't change the revision level when setting the flags,
3487          * so there is a chance incompat flags are set on a rev 0 filesystem.
3488          */
3489         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3490                 goto failed_mount;
3491
3492         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3493         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3494             blocksize > EXT4_MAX_BLOCK_SIZE) {
3495                 ext4_msg(sb, KERN_ERR,
3496                        "Unsupported filesystem blocksize %d", blocksize);
3497                 goto failed_mount;
3498         }
3499
3500         if (sb->s_blocksize != blocksize) {
3501                 /* Validate the filesystem blocksize */
3502                 if (!sb_set_blocksize(sb, blocksize)) {
3503                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3504                                         blocksize);
3505                         goto failed_mount;
3506                 }
3507
3508                 brelse(bh);
3509                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3510                 offset = do_div(logical_sb_block, blocksize);
3511                 bh = sb_bread(sb, logical_sb_block);
3512                 if (!bh) {
3513                         ext4_msg(sb, KERN_ERR,
3514                                "Can't read superblock on 2nd try");
3515                         goto failed_mount;
3516                 }
3517                 es = (struct ext4_super_block *)(bh->b_data + offset);
3518                 sbi->s_es = es;
3519                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3520                         ext4_msg(sb, KERN_ERR,
3521                                "Magic mismatch, very weird!");
3522                         goto failed_mount;
3523                 }
3524         }
3525
3526         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3527                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3528         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3529                                                       has_huge_files);
3530         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3531
3532         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3533                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3534                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3535         } else {
3536                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3537                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3538                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3539                     (!is_power_of_2(sbi->s_inode_size)) ||
3540                     (sbi->s_inode_size > blocksize)) {
3541                         ext4_msg(sb, KERN_ERR,
3542                                "unsupported inode size: %d",
3543                                sbi->s_inode_size);
3544                         goto failed_mount;
3545                 }
3546                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3547                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3548         }
3549
3550         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3551         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3552                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3553                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3554                     !is_power_of_2(sbi->s_desc_size)) {
3555                         ext4_msg(sb, KERN_ERR,
3556                                "unsupported descriptor size %lu",
3557                                sbi->s_desc_size);
3558                         goto failed_mount;
3559                 }
3560         } else
3561                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3562
3563         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3564         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3565         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3566                 goto cantfind_ext4;
3567
3568         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3569         if (sbi->s_inodes_per_block == 0)
3570                 goto cantfind_ext4;
3571         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3572                                         sbi->s_inodes_per_block;
3573         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3574         sbi->s_sbh = bh;
3575         sbi->s_mount_state = le16_to_cpu(es->s_state);
3576         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3577         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3578
3579         for (i = 0; i < 4; i++)
3580                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3581         sbi->s_def_hash_version = es->s_def_hash_version;
3582         i = le32_to_cpu(es->s_flags);
3583         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3584                 sbi->s_hash_unsigned = 3;
3585         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3586 #ifdef __CHAR_UNSIGNED__
3587                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3588                 sbi->s_hash_unsigned = 3;
3589 #else
3590                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3591 #endif
3592         }
3593
3594         /* Handle clustersize */
3595         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3596         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3597                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3598         if (has_bigalloc) {
3599                 if (clustersize < blocksize) {
3600                         ext4_msg(sb, KERN_ERR,
3601                                  "cluster size (%d) smaller than "
3602                                  "block size (%d)", clustersize, blocksize);
3603                         goto failed_mount;
3604                 }
3605                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3606                         le32_to_cpu(es->s_log_block_size);
3607                 sbi->s_clusters_per_group =
3608                         le32_to_cpu(es->s_clusters_per_group);
3609                 if (sbi->s_clusters_per_group > blocksize * 8) {
3610                         ext4_msg(sb, KERN_ERR,
3611                                  "#clusters per group too big: %lu",
3612                                  sbi->s_clusters_per_group);
3613                         goto failed_mount;
3614                 }
3615                 if (sbi->s_blocks_per_group !=
3616                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3617                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3618                                  "clusters per group (%lu) inconsistent",
3619                                  sbi->s_blocks_per_group,
3620                                  sbi->s_clusters_per_group);
3621                         goto failed_mount;
3622                 }
3623         } else {
3624                 if (clustersize != blocksize) {
3625                         ext4_warning(sb, "fragment/cluster size (%d) != "
3626                                      "block size (%d)", clustersize,
3627                                      blocksize);
3628                         clustersize = blocksize;
3629                 }
3630                 if (sbi->s_blocks_per_group > blocksize * 8) {
3631                         ext4_msg(sb, KERN_ERR,
3632                                  "#blocks per group too big: %lu",
3633                                  sbi->s_blocks_per_group);
3634                         goto failed_mount;
3635                 }
3636                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3637                 sbi->s_cluster_bits = 0;
3638         }
3639         sbi->s_cluster_ratio = clustersize / blocksize;
3640
3641         if (sbi->s_inodes_per_group > blocksize * 8) {
3642                 ext4_msg(sb, KERN_ERR,
3643                        "#inodes per group too big: %lu",
3644                        sbi->s_inodes_per_group);
3645                 goto failed_mount;
3646         }
3647
3648         /*
3649          * Test whether we have more sectors than will fit in sector_t,
3650          * and whether the max offset is addressable by the page cache.
3651          */
3652         err = generic_check_addressable(sb->s_blocksize_bits,
3653                                         ext4_blocks_count(es));
3654         if (err) {
3655                 ext4_msg(sb, KERN_ERR, "filesystem"
3656                          " too large to mount safely on this system");
3657                 if (sizeof(sector_t) < 8)
3658                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3659                 goto failed_mount;
3660         }
3661
3662         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3663                 goto cantfind_ext4;
3664
3665         /* check blocks count against device size */
3666         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3667         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3668                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3669                        "exceeds size of device (%llu blocks)",
3670                        ext4_blocks_count(es), blocks_count);
3671                 goto failed_mount;
3672         }
3673
3674         /*
3675          * It makes no sense for the first data block to be beyond the end
3676          * of the filesystem.
3677          */
3678         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3679                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3680                          "block %u is beyond end of filesystem (%llu)",
3681                          le32_to_cpu(es->s_first_data_block),
3682                          ext4_blocks_count(es));
3683                 goto failed_mount;
3684         }
3685         blocks_count = (ext4_blocks_count(es) -
3686                         le32_to_cpu(es->s_first_data_block) +
3687                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3688         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3689         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3690                 ext4_msg(sb, KERN_WARNING, "groups count too large: %u "
3691                        "(block count %llu, first data block %u, "
3692                        "blocks per group %lu)", sbi->s_groups_count,
3693                        ext4_blocks_count(es),
3694                        le32_to_cpu(es->s_first_data_block),
3695                        EXT4_BLOCKS_PER_GROUP(sb));
3696                 goto failed_mount;
3697         }
3698         sbi->s_groups_count = blocks_count;
3699         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3700                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3701         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3702                    EXT4_DESC_PER_BLOCK(sb);
3703         sbi->s_group_desc = ext4_kvmalloc(db_count *
3704                                           sizeof(struct buffer_head *),
3705                                           GFP_KERNEL);
3706         if (sbi->s_group_desc == NULL) {
3707                 ext4_msg(sb, KERN_ERR, "not enough memory");
3708                 ret = -ENOMEM;
3709                 goto failed_mount;
3710         }
3711
3712         if (ext4_proc_root)
3713                 sbi->s_proc = proc_mkdir(sb->s_id, ext4_proc_root);
3714
3715         if (sbi->s_proc)
3716                 proc_create_data("options", S_IRUGO, sbi->s_proc,
3717                                  &ext4_seq_options_fops, sb);
3718
3719         bgl_lock_init(sbi->s_blockgroup_lock);
3720
3721         for (i = 0; i < db_count; i++) {
3722                 block = descriptor_loc(sb, logical_sb_block, i);
3723                 sbi->s_group_desc[i] = sb_bread(sb, block);
3724                 if (!sbi->s_group_desc[i]) {
3725                         ext4_msg(sb, KERN_ERR,
3726                                "can't read group descriptor %d", i);
3727                         db_count = i;
3728                         goto failed_mount2;
3729                 }
3730         }
3731         if (!ext4_check_descriptors(sb, &first_not_zeroed)) {
3732                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
3733                 goto failed_mount2;
3734         }
3735         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
3736                 if (!ext4_fill_flex_info(sb)) {
3737                         ext4_msg(sb, KERN_ERR,
3738                                "unable to initialize "
3739                                "flex_bg meta info!");
3740                         goto failed_mount2;
3741                 }
3742
3743         sbi->s_gdb_count = db_count;
3744         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
3745         spin_lock_init(&sbi->s_next_gen_lock);
3746
3747         init_timer(&sbi->s_err_report);
3748         sbi->s_err_report.function = print_daily_error_info;
3749         sbi->s_err_report.data = (unsigned long) sb;
3750
3751         err = percpu_counter_init(&sbi->s_freeclusters_counter,
3752                         ext4_count_free_clusters(sb));
3753         if (!err) {
3754                 err = percpu_counter_init(&sbi->s_freeinodes_counter,
3755                                 ext4_count_free_inodes(sb));
3756         }
3757         if (!err) {
3758                 err = percpu_counter_init(&sbi->s_dirs_counter,
3759                                 ext4_count_dirs(sb));
3760         }
3761         if (!err) {
3762                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0);
3763         }
3764         if (err) {
3765                 ext4_msg(sb, KERN_ERR, "insufficient memory");
3766                 goto failed_mount3;
3767         }
3768
3769         sbi->s_stripe = ext4_get_stripe_size(sbi);
3770         sbi->s_max_writeback_mb_bump = 128;
3771         sbi->s_extent_max_zeroout_kb = 32;
3772
3773         /*
3774          * set up enough so that it can read an inode
3775          */
3776         if (!test_opt(sb, NOLOAD) &&
3777             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL))
3778                 sb->s_op = &ext4_sops;
3779         else
3780                 sb->s_op = &ext4_nojournal_sops;
3781         sb->s_export_op = &ext4_export_ops;
3782         sb->s_xattr = ext4_xattr_handlers;
3783 #ifdef CONFIG_QUOTA
3784         sb->s_qcop = &ext4_qctl_operations;
3785         sb->dq_op = &ext4_quota_operations;
3786
3787         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) {
3788                 /* Use qctl operations for hidden quota files. */
3789                 sb->s_qcop = &ext4_qctl_sysfile_operations;
3790         }
3791 #endif
3792         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
3793
3794         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
3795         mutex_init(&sbi->s_orphan_lock);
3796
3797         sb->s_root = NULL;
3798
3799         needs_recovery = (es->s_last_orphan != 0 ||
3800                           EXT4_HAS_INCOMPAT_FEATURE(sb,
3801                                     EXT4_FEATURE_INCOMPAT_RECOVER));
3802
3803         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
3804             !(sb->s_flags & MS_RDONLY))
3805                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
3806                         goto failed_mount3;
3807
3808         /*
3809          * The first inode we look at is the journal inode.  Don't try
3810          * root first: it may be modified in the journal!
3811          */
3812         if (!test_opt(sb, NOLOAD) &&
3813             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
3814                 if (ext4_load_journal(sb, es, journal_devnum))
3815                         goto failed_mount3;
3816         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
3817               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
3818                 ext4_msg(sb, KERN_ERR, "required journal recovery "
3819                        "suppressed and not mounted read-only");
3820                 goto failed_mount_wq;
3821         } else {
3822                 clear_opt(sb, DATA_FLAGS);
3823                 sbi->s_journal = NULL;
3824                 needs_recovery = 0;
3825                 goto no_journal;
3826         }
3827
3828         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT) &&
3829             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
3830                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
3831                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
3832                 goto failed_mount_wq;
3833         }
3834
3835         if (!set_journal_csum_feature_set(sb)) {
3836                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
3837                          "feature set");
3838                 goto failed_mount_wq;
3839         }
3840
3841         /* We have now updated the journal if required, so we can
3842          * validate the data journaling mode. */
3843         switch (test_opt(sb, DATA_FLAGS)) {
3844         case 0:
3845                 /* No mode set, assume a default based on the journal
3846                  * capabilities: ORDERED_DATA if the journal can
3847                  * cope, else JOURNAL_DATA
3848                  */
3849                 if (jbd2_journal_check_available_features
3850                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
3851                         set_opt(sb, ORDERED_DATA);
3852                 else
3853                         set_opt(sb, JOURNAL_DATA);
3854                 break;
3855
3856         case EXT4_MOUNT_ORDERED_DATA:
3857         case EXT4_MOUNT_WRITEBACK_DATA:
3858                 if (!jbd2_journal_check_available_features
3859                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
3860                         ext4_msg(sb, KERN_ERR, "Journal does not support "
3861                                "requested data journaling mode");
3862                         goto failed_mount_wq;
3863                 }
3864         default:
3865                 break;
3866         }
3867         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
3868
3869         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
3870
3871         /*
3872          * The journal may have updated the bg summary counts, so we
3873          * need to update the global counters.
3874          */
3875         percpu_counter_set(&sbi->s_freeclusters_counter,
3876                            ext4_count_free_clusters(sb));
3877         percpu_counter_set(&sbi->s_freeinodes_counter,
3878                            ext4_count_free_inodes(sb));
3879         percpu_counter_set(&sbi->s_dirs_counter,
3880                            ext4_count_dirs(sb));
3881         percpu_counter_set(&sbi->s_dirtyclusters_counter, 0);
3882
3883 no_journal:
3884         /*
3885          * Get the # of file system overhead blocks from the
3886          * superblock if present.
3887          */
3888         if (es->s_overhead_clusters)
3889                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
3890         else {
3891                 err = ext4_calculate_overhead(sb);