Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
[~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"
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 void ext4_write_super(struct super_block *sb);
78 static int ext4_freeze(struct super_block *sb);
79 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
80                        const char *dev_name, void *data);
81 static inline int ext2_feature_set_ok(struct super_block *sb);
82 static inline int ext3_feature_set_ok(struct super_block *sb);
83 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
84 static void ext4_destroy_lazyinit_thread(void);
85 static void ext4_unregister_li_request(struct super_block *sb);
86 static void ext4_clear_request_list(void);
87
88 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
89 static struct file_system_type ext2_fs_type = {
90         .owner          = THIS_MODULE,
91         .name           = "ext2",
92         .mount          = ext4_mount,
93         .kill_sb        = kill_block_super,
94         .fs_flags       = FS_REQUIRES_DEV,
95 };
96 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
97 #else
98 #define IS_EXT2_SB(sb) (0)
99 #endif
100
101
102 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
103 static struct file_system_type ext3_fs_type = {
104         .owner          = THIS_MODULE,
105         .name           = "ext3",
106         .mount          = ext4_mount,
107         .kill_sb        = kill_block_super,
108         .fs_flags       = FS_REQUIRES_DEV,
109 };
110 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
111 #else
112 #define IS_EXT3_SB(sb) (0)
113 #endif
114
115 void *ext4_kvmalloc(size_t size, gfp_t flags)
116 {
117         void *ret;
118
119         ret = kmalloc(size, flags);
120         if (!ret)
121                 ret = __vmalloc(size, flags, PAGE_KERNEL);
122         return ret;
123 }
124
125 void *ext4_kvzalloc(size_t size, gfp_t flags)
126 {
127         void *ret;
128
129         ret = kzalloc(size, flags);
130         if (!ret)
131                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
132         return ret;
133 }
134
135 void ext4_kvfree(void *ptr)
136 {
137         if (is_vmalloc_addr(ptr))
138                 vfree(ptr);
139         else
140                 kfree(ptr);
141
142 }
143
144 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
145                                struct ext4_group_desc *bg)
146 {
147         return le32_to_cpu(bg->bg_block_bitmap_lo) |
148                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
149                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
150 }
151
152 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
153                                struct ext4_group_desc *bg)
154 {
155         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
156                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
157                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
158 }
159
160 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
161                               struct ext4_group_desc *bg)
162 {
163         return le32_to_cpu(bg->bg_inode_table_lo) |
164                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
165                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
166 }
167
168 __u32 ext4_free_group_clusters(struct super_block *sb,
169                                struct ext4_group_desc *bg)
170 {
171         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
172                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
173                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
174 }
175
176 __u32 ext4_free_inodes_count(struct super_block *sb,
177                               struct ext4_group_desc *bg)
178 {
179         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
180                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
181                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
182 }
183
184 __u32 ext4_used_dirs_count(struct super_block *sb,
185                               struct ext4_group_desc *bg)
186 {
187         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
188                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
189                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
190 }
191
192 __u32 ext4_itable_unused_count(struct super_block *sb,
193                               struct ext4_group_desc *bg)
194 {
195         return le16_to_cpu(bg->bg_itable_unused_lo) |
196                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
197                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
198 }
199
200 void ext4_block_bitmap_set(struct super_block *sb,
201                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
202 {
203         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
204         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
205                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
206 }
207
208 void ext4_inode_bitmap_set(struct super_block *sb,
209                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
210 {
211         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
212         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
213                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
214 }
215
216 void ext4_inode_table_set(struct super_block *sb,
217                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
218 {
219         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
220         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
221                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
222 }
223
224 void ext4_free_group_clusters_set(struct super_block *sb,
225                                   struct ext4_group_desc *bg, __u32 count)
226 {
227         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
228         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
229                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
230 }
231
232 void ext4_free_inodes_set(struct super_block *sb,
233                           struct ext4_group_desc *bg, __u32 count)
234 {
235         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
236         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
237                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
238 }
239
240 void ext4_used_dirs_set(struct super_block *sb,
241                           struct ext4_group_desc *bg, __u32 count)
242 {
243         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
244         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
245                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
246 }
247
248 void ext4_itable_unused_set(struct super_block *sb,
249                           struct ext4_group_desc *bg, __u32 count)
250 {
251         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
252         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
253                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
254 }
255
256
257 /* Just increment the non-pointer handle value */
258 static handle_t *ext4_get_nojournal(void)
259 {
260         handle_t *handle = current->journal_info;
261         unsigned long ref_cnt = (unsigned long)handle;
262
263         BUG_ON(ref_cnt >= EXT4_NOJOURNAL_MAX_REF_COUNT);
264
265         ref_cnt++;
266         handle = (handle_t *)ref_cnt;
267
268         current->journal_info = handle;
269         return handle;
270 }
271
272
273 /* Decrement the non-pointer handle value */
274 static void ext4_put_nojournal(handle_t *handle)
275 {
276         unsigned long ref_cnt = (unsigned long)handle;
277
278         BUG_ON(ref_cnt == 0);
279
280         ref_cnt--;
281         handle = (handle_t *)ref_cnt;
282
283         current->journal_info = handle;
284 }
285
286 /*
287  * Wrappers for jbd2_journal_start/end.
288  *
289  * The only special thing we need to do here is to make sure that all
290  * journal_end calls result in the superblock being marked dirty, so
291  * that sync() will call the filesystem's write_super callback if
292  * appropriate.
293  *
294  * To avoid j_barrier hold in userspace when a user calls freeze(),
295  * ext4 prevents a new handle from being started by s_frozen, which
296  * is in an upper layer.
297  */
298 handle_t *ext4_journal_start_sb(struct super_block *sb, int nblocks)
299 {
300         journal_t *journal;
301         handle_t  *handle;
302
303         trace_ext4_journal_start(sb, nblocks, _RET_IP_);
304         if (sb->s_flags & MS_RDONLY)
305                 return ERR_PTR(-EROFS);
306
307         journal = EXT4_SB(sb)->s_journal;
308         handle = ext4_journal_current_handle();
309
310         /*
311          * If a handle has been started, it should be allowed to
312          * finish, otherwise deadlock could happen between freeze
313          * and others(e.g. truncate) due to the restart of the
314          * journal handle if the filesystem is forzen and active
315          * handles are not stopped.
316          */
317         if (!handle)
318                 vfs_check_frozen(sb, SB_FREEZE_TRANS);
319
320         if (!journal)
321                 return ext4_get_nojournal();
322         /*
323          * Special case here: if the journal has aborted behind our
324          * backs (eg. EIO in the commit thread), then we still need to
325          * take the FS itself readonly cleanly.
326          */
327         if (is_journal_aborted(journal)) {
328                 ext4_abort(sb, "Detected aborted journal");
329                 return ERR_PTR(-EROFS);
330         }
331         return jbd2_journal_start(journal, nblocks);
332 }
333
334 /*
335  * The only special thing we need to do here is to make sure that all
336  * jbd2_journal_stop calls result in the superblock being marked dirty, so
337  * that sync() will call the filesystem's write_super callback if
338  * appropriate.
339  */
340 int __ext4_journal_stop(const char *where, unsigned int line, handle_t *handle)
341 {
342         struct super_block *sb;
343         int err;
344         int rc;
345
346         if (!ext4_handle_valid(handle)) {
347                 ext4_put_nojournal(handle);
348                 return 0;
349         }
350         sb = handle->h_transaction->t_journal->j_private;
351         err = handle->h_err;
352         rc = jbd2_journal_stop(handle);
353
354         if (!err)
355                 err = rc;
356         if (err)
357                 __ext4_std_error(sb, where, line, err);
358         return err;
359 }
360
361 void ext4_journal_abort_handle(const char *caller, unsigned int line,
362                                const char *err_fn, struct buffer_head *bh,
363                                handle_t *handle, int err)
364 {
365         char nbuf[16];
366         const char *errstr = ext4_decode_error(NULL, err, nbuf);
367
368         BUG_ON(!ext4_handle_valid(handle));
369
370         if (bh)
371                 BUFFER_TRACE(bh, "abort");
372
373         if (!handle->h_err)
374                 handle->h_err = err;
375
376         if (is_handle_aborted(handle))
377                 return;
378
379         printk(KERN_ERR "EXT4-fs: %s:%d: aborting transaction: %s in %s\n",
380                caller, line, errstr, err_fn);
381
382         jbd2_journal_abort_handle(handle);
383 }
384
385 static void __save_error_info(struct super_block *sb, const char *func,
386                             unsigned int line)
387 {
388         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
389
390         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
391         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
392         es->s_last_error_time = cpu_to_le32(get_seconds());
393         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
394         es->s_last_error_line = cpu_to_le32(line);
395         if (!es->s_first_error_time) {
396                 es->s_first_error_time = es->s_last_error_time;
397                 strncpy(es->s_first_error_func, func,
398                         sizeof(es->s_first_error_func));
399                 es->s_first_error_line = cpu_to_le32(line);
400                 es->s_first_error_ino = es->s_last_error_ino;
401                 es->s_first_error_block = es->s_last_error_block;
402         }
403         /*
404          * Start the daily error reporting function if it hasn't been
405          * started already
406          */
407         if (!es->s_error_count)
408                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
409         es->s_error_count = cpu_to_le32(le32_to_cpu(es->s_error_count) + 1);
410 }
411
412 static void save_error_info(struct super_block *sb, const char *func,
413                             unsigned int line)
414 {
415         __save_error_info(sb, func, line);
416         ext4_commit_super(sb, 1);
417 }
418
419 /*
420  * The del_gendisk() function uninitializes the disk-specific data
421  * structures, including the bdi structure, without telling anyone
422  * else.  Once this happens, any attempt to call mark_buffer_dirty()
423  * (for example, by ext4_commit_super), will cause a kernel OOPS.
424  * This is a kludge to prevent these oops until we can put in a proper
425  * hook in del_gendisk() to inform the VFS and file system layers.
426  */
427 static int block_device_ejected(struct super_block *sb)
428 {
429         struct inode *bd_inode = sb->s_bdev->bd_inode;
430         struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info;
431
432         return bdi->dev == NULL;
433 }
434
435 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
436 {
437         struct super_block              *sb = journal->j_private;
438         struct ext4_sb_info             *sbi = EXT4_SB(sb);
439         int                             error = is_journal_aborted(journal);
440         struct ext4_journal_cb_entry    *jce, *tmp;
441
442         spin_lock(&sbi->s_md_lock);
443         list_for_each_entry_safe(jce, tmp, &txn->t_private_list, jce_list) {
444                 list_del_init(&jce->jce_list);
445                 spin_unlock(&sbi->s_md_lock);
446                 jce->jce_func(sb, jce, error);
447                 spin_lock(&sbi->s_md_lock);
448         }
449         spin_unlock(&sbi->s_md_lock);
450 }
451
452 /* Deal with the reporting of failure conditions on a filesystem such as
453  * inconsistencies detected or read IO failures.
454  *
455  * On ext2, we can store the error state of the filesystem in the
456  * superblock.  That is not possible on ext4, because we may have other
457  * write ordering constraints on the superblock which prevent us from
458  * writing it out straight away; and given that the journal is about to
459  * be aborted, we can't rely on the current, or future, transactions to
460  * write out the superblock safely.
461  *
462  * We'll just use the jbd2_journal_abort() error code to record an error in
463  * the journal instead.  On recovery, the journal will complain about
464  * that error until we've noted it down and cleared it.
465  */
466
467 static void ext4_handle_error(struct super_block *sb)
468 {
469         if (sb->s_flags & MS_RDONLY)
470                 return;
471
472         if (!test_opt(sb, ERRORS_CONT)) {
473                 journal_t *journal = EXT4_SB(sb)->s_journal;
474
475                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
476                 if (journal)
477                         jbd2_journal_abort(journal, -EIO);
478         }
479         if (test_opt(sb, ERRORS_RO)) {
480                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
481                 sb->s_flags |= MS_RDONLY;
482         }
483         if (test_opt(sb, ERRORS_PANIC))
484                 panic("EXT4-fs (device %s): panic forced after error\n",
485                         sb->s_id);
486 }
487
488 void __ext4_error(struct super_block *sb, const char *function,
489                   unsigned int line, const char *fmt, ...)
490 {
491         struct va_format vaf;
492         va_list args;
493
494         va_start(args, fmt);
495         vaf.fmt = fmt;
496         vaf.va = &args;
497         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
498                sb->s_id, function, line, current->comm, &vaf);
499         va_end(args);
500
501         ext4_handle_error(sb);
502 }
503
504 void ext4_error_inode(struct inode *inode, const char *function,
505                       unsigned int line, ext4_fsblk_t block,
506                       const char *fmt, ...)
507 {
508         va_list args;
509         struct va_format vaf;
510         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
511
512         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
513         es->s_last_error_block = cpu_to_le64(block);
514         save_error_info(inode->i_sb, function, line);
515         va_start(args, fmt);
516         vaf.fmt = fmt;
517         vaf.va = &args;
518         if (block)
519                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
520                        "inode #%lu: block %llu: comm %s: %pV\n",
521                        inode->i_sb->s_id, function, line, inode->i_ino,
522                        block, current->comm, &vaf);
523         else
524                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
525                        "inode #%lu: comm %s: %pV\n",
526                        inode->i_sb->s_id, function, line, inode->i_ino,
527                        current->comm, &vaf);
528         va_end(args);
529
530         ext4_handle_error(inode->i_sb);
531 }
532
533 void ext4_error_file(struct file *file, const char *function,
534                      unsigned int line, ext4_fsblk_t block,
535                      const char *fmt, ...)
536 {
537         va_list args;
538         struct va_format vaf;
539         struct ext4_super_block *es;
540         struct inode *inode = file->f_dentry->d_inode;
541         char pathname[80], *path;
542
543         es = EXT4_SB(inode->i_sb)->s_es;
544         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
545         save_error_info(inode->i_sb, function, line);
546         path = d_path(&(file->f_path), pathname, sizeof(pathname));
547         if (IS_ERR(path))
548                 path = "(unknown)";
549         va_start(args, fmt);
550         vaf.fmt = fmt;
551         vaf.va = &args;
552         if (block)
553                 printk(KERN_CRIT
554                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
555                        "block %llu: comm %s: path %s: %pV\n",
556                        inode->i_sb->s_id, function, line, inode->i_ino,
557                        block, current->comm, path, &vaf);
558         else
559                 printk(KERN_CRIT
560                        "EXT4-fs error (device %s): %s:%d: inode #%lu: "
561                        "comm %s: path %s: %pV\n",
562                        inode->i_sb->s_id, function, line, inode->i_ino,
563                        current->comm, path, &vaf);
564         va_end(args);
565
566         ext4_handle_error(inode->i_sb);
567 }
568
569 static const char *ext4_decode_error(struct super_block *sb, int errno,
570                                      char nbuf[16])
571 {
572         char *errstr = NULL;
573
574         switch (errno) {
575         case -EIO:
576                 errstr = "IO failure";
577                 break;
578         case -ENOMEM:
579                 errstr = "Out of memory";
580                 break;
581         case -EROFS:
582                 if (!sb || (EXT4_SB(sb)->s_journal &&
583                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
584                         errstr = "Journal has aborted";
585                 else
586                         errstr = "Readonly filesystem";
587                 break;
588         default:
589                 /* If the caller passed in an extra buffer for unknown
590                  * errors, textualise them now.  Else we just return
591                  * NULL. */
592                 if (nbuf) {
593                         /* Check for truncated error codes... */
594                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
595                                 errstr = nbuf;
596                 }
597                 break;
598         }
599
600         return errstr;
601 }
602
603 /* __ext4_std_error decodes expected errors from journaling functions
604  * automatically and invokes the appropriate error response.  */
605
606 void __ext4_std_error(struct super_block *sb, const char *function,
607                       unsigned int line, int errno)
608 {
609         char nbuf[16];
610         const char *errstr;
611
612         /* Special case: if the error is EROFS, and we're not already
613          * inside a transaction, then there's really no point in logging
614          * an error. */
615         if (errno == -EROFS && journal_current_handle() == NULL &&
616             (sb->s_flags & MS_RDONLY))
617                 return;
618
619         errstr = ext4_decode_error(sb, errno, nbuf);
620         printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
621                sb->s_id, function, line, errstr);
622         save_error_info(sb, function, line);
623
624         ext4_handle_error(sb);
625 }
626
627 /*
628  * ext4_abort is a much stronger failure handler than ext4_error.  The
629  * abort function may be used to deal with unrecoverable failures such
630  * as journal IO errors or ENOMEM at a critical moment in log management.
631  *
632  * We unconditionally force the filesystem into an ABORT|READONLY state,
633  * unless the error response on the fs has been set to panic in which
634  * case we take the easy way out and panic immediately.
635  */
636
637 void __ext4_abort(struct super_block *sb, const char *function,
638                 unsigned int line, const char *fmt, ...)
639 {
640         va_list args;
641
642         save_error_info(sb, function, line);
643         va_start(args, fmt);
644         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
645                function, line);
646         vprintk(fmt, args);
647         printk("\n");
648         va_end(args);
649
650         if ((sb->s_flags & MS_RDONLY) == 0) {
651                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
652                 sb->s_flags |= MS_RDONLY;
653                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
654                 if (EXT4_SB(sb)->s_journal)
655                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
656                 save_error_info(sb, function, line);
657         }
658         if (test_opt(sb, ERRORS_PANIC))
659                 panic("EXT4-fs panic from previous error\n");
660 }
661
662 void ext4_msg(struct super_block *sb, const char *prefix, const char *fmt, ...)
663 {
664         struct va_format vaf;
665         va_list args;
666
667         va_start(args, fmt);
668         vaf.fmt = fmt;
669         vaf.va = &args;
670         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
671         va_end(args);
672 }
673
674 void __ext4_warning(struct super_block *sb, const char *function,
675                     unsigned int line, const char *fmt, ...)
676 {
677         struct va_format vaf;
678         va_list args;
679
680         va_start(args, fmt);
681         vaf.fmt = fmt;
682         vaf.va = &args;
683         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
684                sb->s_id, function, line, &vaf);
685         va_end(args);
686 }
687
688 void __ext4_grp_locked_error(const char *function, unsigned int line,
689                              struct super_block *sb, ext4_group_t grp,
690                              unsigned long ino, ext4_fsblk_t block,
691                              const char *fmt, ...)
692 __releases(bitlock)
693 __acquires(bitlock)
694 {
695         struct va_format vaf;
696         va_list args;
697         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
698
699         es->s_last_error_ino = cpu_to_le32(ino);
700         es->s_last_error_block = cpu_to_le64(block);
701         __save_error_info(sb, function, line);
702
703         va_start(args, fmt);
704
705         vaf.fmt = fmt;
706         vaf.va = &args;
707         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
708                sb->s_id, function, line, grp);
709         if (ino)
710                 printk(KERN_CONT "inode %lu: ", ino);
711         if (block)
712                 printk(KERN_CONT "block %llu:", (unsigned long long) block);
713         printk(KERN_CONT "%pV\n", &vaf);
714         va_end(args);
715
716         if (test_opt(sb, ERRORS_CONT)) {
717                 ext4_commit_super(sb, 0);
718                 return;
719         }
720
721         ext4_unlock_group(sb, grp);
722         ext4_handle_error(sb);
723         /*
724          * We only get here in the ERRORS_RO case; relocking the group
725          * may be dangerous, but nothing bad will happen since the
726          * filesystem will have already been marked read/only and the
727          * journal has been aborted.  We return 1 as a hint to callers
728          * who might what to use the return value from
729          * ext4_grp_locked_error() to distinguish between the
730          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
731          * aggressively from the ext4 function in question, with a
732          * more appropriate error code.
733          */
734         ext4_lock_group(sb, grp);
735         return;
736 }
737
738 void ext4_update_dynamic_rev(struct super_block *sb)
739 {
740         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
741
742         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
743                 return;
744
745         ext4_warning(sb,
746                      "updating to rev %d because of new feature flag, "
747                      "running e2fsck is recommended",
748                      EXT4_DYNAMIC_REV);
749
750         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
751         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
752         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
753         /* leave es->s_feature_*compat flags alone */
754         /* es->s_uuid will be set by e2fsck if empty */
755
756         /*
757          * The rest of the superblock fields should be zero, and if not it
758          * means they are likely already in use, so leave them alone.  We
759          * can leave it up to e2fsck to clean up any inconsistencies there.
760          */
761 }
762
763 /*
764  * Open the external journal device
765  */
766 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
767 {
768         struct block_device *bdev;
769         char b[BDEVNAME_SIZE];
770
771         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
772         if (IS_ERR(bdev))
773                 goto fail;
774         return bdev;
775
776 fail:
777         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
778                         __bdevname(dev, b), PTR_ERR(bdev));
779         return NULL;
780 }
781
782 /*
783  * Release the journal device
784  */
785 static int ext4_blkdev_put(struct block_device *bdev)
786 {
787         return blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
788 }
789
790 static int ext4_blkdev_remove(struct ext4_sb_info *sbi)
791 {
792         struct block_device *bdev;
793         int ret = -ENODEV;
794
795         bdev = sbi->journal_bdev;
796         if (bdev) {
797                 ret = ext4_blkdev_put(bdev);
798                 sbi->journal_bdev = NULL;
799         }
800         return ret;
801 }
802
803 static inline struct inode *orphan_list_entry(struct list_head *l)
804 {
805         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
806 }
807
808 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
809 {
810         struct list_head *l;
811
812         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
813                  le32_to_cpu(sbi->s_es->s_last_orphan));
814
815         printk(KERN_ERR "sb_info orphan list:\n");
816         list_for_each(l, &sbi->s_orphan) {
817                 struct inode *inode = orphan_list_entry(l);
818                 printk(KERN_ERR "  "
819                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
820                        inode->i_sb->s_id, inode->i_ino, inode,
821                        inode->i_mode, inode->i_nlink,
822                        NEXT_ORPHAN(inode));
823         }
824 }
825
826 static void ext4_put_super(struct super_block *sb)
827 {
828         struct ext4_sb_info *sbi = EXT4_SB(sb);
829         struct ext4_super_block *es = sbi->s_es;
830         int i, err;
831
832         ext4_unregister_li_request(sb);
833         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
834
835         flush_workqueue(sbi->dio_unwritten_wq);
836         destroy_workqueue(sbi->dio_unwritten_wq);
837
838         lock_super(sb);
839         if (sbi->s_journal) {
840                 err = jbd2_journal_destroy(sbi->s_journal);
841                 sbi->s_journal = NULL;
842                 if (err < 0)
843                         ext4_abort(sb, "Couldn't clean up the journal");
844         }
845
846         del_timer(&sbi->s_err_report);
847         ext4_release_system_zone(sb);
848         ext4_mb_release(sb);
849         ext4_ext_release(sb);
850         ext4_xattr_put_super(sb);
851
852         if (!(sb->s_flags & MS_RDONLY)) {
853                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
854                 es->s_state = cpu_to_le16(sbi->s_mount_state);
855         }
856         if (sb->s_dirt || !(sb->s_flags & MS_RDONLY))
857                 ext4_commit_super(sb, 1);
858
859         if (sbi->s_proc) {
860                 remove_proc_entry("options", sbi->s_proc);
861                 remove_proc_entry(sb->s_id, ext4_proc_root);
862         }
863         kobject_del(&sbi->s_kobj);
864
865         for (i = 0; i < sbi->s_gdb_count; i++)
866                 brelse(sbi->s_group_desc[i]);
867         ext4_kvfree(sbi->s_group_desc);
868         ext4_kvfree(sbi->s_flex_groups);
869         percpu_counter_destroy(&sbi->s_freeclusters_counter);
870         percpu_counter_destroy(&sbi->s_freeinodes_counter);
871         percpu_counter_destroy(&sbi->s_dirs_counter);
872         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
873         brelse(sbi->s_sbh);
874 #ifdef CONFIG_QUOTA
875         for (i = 0; i < MAXQUOTAS; i++)
876                 kfree(sbi->s_qf_names[i]);
877 #endif
878
879         /* Debugging code just in case the in-memory inode orphan list
880          * isn't empty.  The on-disk one can be non-empty if we've
881          * detected an error and taken the fs readonly, but the
882          * in-memory list had better be clean by this point. */
883         if (!list_empty(&sbi->s_orphan))
884                 dump_orphan_list(sb, sbi);
885         J_ASSERT(list_empty(&sbi->s_orphan));
886
887         invalidate_bdev(sb->s_bdev);
888         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
889                 /*
890                  * Invalidate the journal device's buffers.  We don't want them
891                  * floating about in memory - the physical journal device may
892                  * hotswapped, and it breaks the `ro-after' testing code.
893                  */
894                 sync_blockdev(sbi->journal_bdev);
895                 invalidate_bdev(sbi->journal_bdev);
896                 ext4_blkdev_remove(sbi);
897         }
898         if (sbi->s_mmp_tsk)
899                 kthread_stop(sbi->s_mmp_tsk);
900         sb->s_fs_info = NULL;
901         /*
902          * Now that we are completely done shutting down the
903          * superblock, we need to actually destroy the kobject.
904          */
905         unlock_super(sb);
906         kobject_put(&sbi->s_kobj);
907         wait_for_completion(&sbi->s_kobj_unregister);
908         kfree(sbi->s_blockgroup_lock);
909         kfree(sbi);
910 }
911
912 static struct kmem_cache *ext4_inode_cachep;
913
914 /*
915  * Called inside transaction, so use GFP_NOFS
916  */
917 static struct inode *ext4_alloc_inode(struct super_block *sb)
918 {
919         struct ext4_inode_info *ei;
920
921         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
922         if (!ei)
923                 return NULL;
924
925         ei->vfs_inode.i_version = 1;
926         ei->vfs_inode.i_data.writeback_index = 0;
927         memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
928         INIT_LIST_HEAD(&ei->i_prealloc_list);
929         spin_lock_init(&ei->i_prealloc_lock);
930         ei->i_reserved_data_blocks = 0;
931         ei->i_reserved_meta_blocks = 0;
932         ei->i_allocated_meta_blocks = 0;
933         ei->i_da_metadata_calc_len = 0;
934         spin_lock_init(&(ei->i_block_reservation_lock));
935 #ifdef CONFIG_QUOTA
936         ei->i_reserved_quota = 0;
937 #endif
938         ei->jinode = NULL;
939         INIT_LIST_HEAD(&ei->i_completed_io_list);
940         spin_lock_init(&ei->i_completed_io_lock);
941         ei->cur_aio_dio = NULL;
942         ei->i_sync_tid = 0;
943         ei->i_datasync_tid = 0;
944         atomic_set(&ei->i_ioend_count, 0);
945         atomic_set(&ei->i_aiodio_unwritten, 0);
946
947         return &ei->vfs_inode;
948 }
949
950 static int ext4_drop_inode(struct inode *inode)
951 {
952         int drop = generic_drop_inode(inode);
953
954         trace_ext4_drop_inode(inode, drop);
955         return drop;
956 }
957
958 static void ext4_i_callback(struct rcu_head *head)
959 {
960         struct inode *inode = container_of(head, struct inode, i_rcu);
961         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
962 }
963
964 static void ext4_destroy_inode(struct inode *inode)
965 {
966         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
967                 ext4_msg(inode->i_sb, KERN_ERR,
968                          "Inode %lu (%p): orphan list check failed!",
969                          inode->i_ino, EXT4_I(inode));
970                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
971                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
972                                 true);
973                 dump_stack();
974         }
975         call_rcu(&inode->i_rcu, ext4_i_callback);
976 }
977
978 static void init_once(void *foo)
979 {
980         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
981
982         INIT_LIST_HEAD(&ei->i_orphan);
983 #ifdef CONFIG_EXT4_FS_XATTR
984         init_rwsem(&ei->xattr_sem);
985 #endif
986         init_rwsem(&ei->i_data_sem);
987         inode_init_once(&ei->vfs_inode);
988 }
989
990 static int init_inodecache(void)
991 {
992         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
993                                              sizeof(struct ext4_inode_info),
994                                              0, (SLAB_RECLAIM_ACCOUNT|
995                                                 SLAB_MEM_SPREAD),
996                                              init_once);
997         if (ext4_inode_cachep == NULL)
998                 return -ENOMEM;
999         return 0;
1000 }
1001
1002 static void destroy_inodecache(void)
1003 {
1004         kmem_cache_destroy(ext4_inode_cachep);
1005 }
1006
1007 void ext4_clear_inode(struct inode *inode)
1008 {
1009         invalidate_inode_buffers(inode);
1010         end_writeback(inode);
1011         dquot_drop(inode);
1012         ext4_discard_preallocations(inode);
1013         if (EXT4_I(inode)->jinode) {
1014                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1015                                                EXT4_I(inode)->jinode);
1016                 jbd2_free_inode(EXT4_I(inode)->jinode);
1017                 EXT4_I(inode)->jinode = NULL;
1018         }
1019 }
1020
1021 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1022                                         u64 ino, u32 generation)
1023 {
1024         struct inode *inode;
1025
1026         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1027                 return ERR_PTR(-ESTALE);
1028         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1029                 return ERR_PTR(-ESTALE);
1030
1031         /* iget isn't really right if the inode is currently unallocated!!
1032          *
1033          * ext4_read_inode will return a bad_inode if the inode had been
1034          * deleted, so we should be safe.
1035          *
1036          * Currently we don't know the generation for parent directory, so
1037          * a generation of 0 means "accept any"
1038          */
1039         inode = ext4_iget(sb, ino);
1040         if (IS_ERR(inode))
1041                 return ERR_CAST(inode);
1042         if (generation && inode->i_generation != generation) {
1043                 iput(inode);
1044                 return ERR_PTR(-ESTALE);
1045         }
1046
1047         return inode;
1048 }
1049
1050 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1051                                         int fh_len, int fh_type)
1052 {
1053         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1054                                     ext4_nfs_get_inode);
1055 }
1056
1057 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1058                                         int fh_len, int fh_type)
1059 {
1060         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1061                                     ext4_nfs_get_inode);
1062 }
1063
1064 /*
1065  * Try to release metadata pages (indirect blocks, directories) which are
1066  * mapped via the block device.  Since these pages could have journal heads
1067  * which would prevent try_to_free_buffers() from freeing them, we must use
1068  * jbd2 layer's try_to_free_buffers() function to release them.
1069  */
1070 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1071                                  gfp_t wait)
1072 {
1073         journal_t *journal = EXT4_SB(sb)->s_journal;
1074
1075         WARN_ON(PageChecked(page));
1076         if (!page_has_buffers(page))
1077                 return 0;
1078         if (journal)
1079                 return jbd2_journal_try_to_free_buffers(journal, page,
1080                                                         wait & ~__GFP_WAIT);
1081         return try_to_free_buffers(page);
1082 }
1083
1084 #ifdef CONFIG_QUOTA
1085 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1086 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1087
1088 static int ext4_write_dquot(struct dquot *dquot);
1089 static int ext4_acquire_dquot(struct dquot *dquot);
1090 static int ext4_release_dquot(struct dquot *dquot);
1091 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1092 static int ext4_write_info(struct super_block *sb, int type);
1093 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1094                          struct path *path);
1095 static int ext4_quota_off(struct super_block *sb, int type);
1096 static int ext4_quota_on_mount(struct super_block *sb, int type);
1097 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1098                                size_t len, loff_t off);
1099 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1100                                 const char *data, size_t len, loff_t off);
1101
1102 static const struct dquot_operations ext4_quota_operations = {
1103         .get_reserved_space = ext4_get_reserved_space,
1104         .write_dquot    = ext4_write_dquot,
1105         .acquire_dquot  = ext4_acquire_dquot,
1106         .release_dquot  = ext4_release_dquot,
1107         .mark_dirty     = ext4_mark_dquot_dirty,
1108         .write_info     = ext4_write_info,
1109         .alloc_dquot    = dquot_alloc,
1110         .destroy_dquot  = dquot_destroy,
1111 };
1112
1113 static const struct quotactl_ops ext4_qctl_operations = {
1114         .quota_on       = ext4_quota_on,
1115         .quota_off      = ext4_quota_off,
1116         .quota_sync     = dquot_quota_sync,
1117         .get_info       = dquot_get_dqinfo,
1118         .set_info       = dquot_set_dqinfo,
1119         .get_dqblk      = dquot_get_dqblk,
1120         .set_dqblk      = dquot_set_dqblk
1121 };
1122 #endif
1123
1124 static const struct super_operations ext4_sops = {
1125         .alloc_inode    = ext4_alloc_inode,
1126         .destroy_inode  = ext4_destroy_inode,
1127         .write_inode    = ext4_write_inode,
1128         .dirty_inode    = ext4_dirty_inode,
1129         .drop_inode     = ext4_drop_inode,
1130         .evict_inode    = ext4_evict_inode,
1131         .put_super      = ext4_put_super,
1132         .sync_fs        = ext4_sync_fs,
1133         .freeze_fs      = ext4_freeze,
1134         .unfreeze_fs    = ext4_unfreeze,
1135         .statfs         = ext4_statfs,
1136         .remount_fs     = ext4_remount,
1137         .show_options   = ext4_show_options,
1138 #ifdef CONFIG_QUOTA
1139         .quota_read     = ext4_quota_read,
1140         .quota_write    = ext4_quota_write,
1141 #endif
1142         .bdev_try_to_free_page = bdev_try_to_free_page,
1143 };
1144
1145 static const struct super_operations ext4_nojournal_sops = {
1146         .alloc_inode    = ext4_alloc_inode,
1147         .destroy_inode  = ext4_destroy_inode,
1148         .write_inode    = ext4_write_inode,
1149         .dirty_inode    = ext4_dirty_inode,
1150         .drop_inode     = ext4_drop_inode,
1151         .evict_inode    = ext4_evict_inode,
1152         .write_super    = ext4_write_super,
1153         .put_super      = ext4_put_super,
1154         .statfs         = ext4_statfs,
1155         .remount_fs     = ext4_remount,
1156         .show_options   = ext4_show_options,
1157 #ifdef CONFIG_QUOTA
1158         .quota_read     = ext4_quota_read,
1159         .quota_write    = ext4_quota_write,
1160 #endif
1161         .bdev_try_to_free_page = bdev_try_to_free_page,
1162 };
1163
1164 static const struct export_operations ext4_export_ops = {
1165         .fh_to_dentry = ext4_fh_to_dentry,
1166         .fh_to_parent = ext4_fh_to_parent,
1167         .get_parent = ext4_get_parent,
1168 };
1169
1170 enum {
1171         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1172         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1173         Opt_nouid32, Opt_debug, Opt_removed,
1174         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1175         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1176         Opt_commit, Opt_min_batch_time, Opt_max_batch_time,
1177         Opt_journal_dev, Opt_journal_checksum, Opt_journal_async_commit,
1178         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1179         Opt_data_err_abort, Opt_data_err_ignore,
1180         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1181         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1182         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1183         Opt_usrquota, Opt_grpquota, Opt_i_version,
1184         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1185         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1186         Opt_inode_readahead_blks, Opt_journal_ioprio,
1187         Opt_dioread_nolock, Opt_dioread_lock,
1188         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1189 };
1190
1191 static const match_table_t tokens = {
1192         {Opt_bsd_df, "bsddf"},
1193         {Opt_minix_df, "minixdf"},
1194         {Opt_grpid, "grpid"},
1195         {Opt_grpid, "bsdgroups"},
1196         {Opt_nogrpid, "nogrpid"},
1197         {Opt_nogrpid, "sysvgroups"},
1198         {Opt_resgid, "resgid=%u"},
1199         {Opt_resuid, "resuid=%u"},
1200         {Opt_sb, "sb=%u"},
1201         {Opt_err_cont, "errors=continue"},
1202         {Opt_err_panic, "errors=panic"},
1203         {Opt_err_ro, "errors=remount-ro"},
1204         {Opt_nouid32, "nouid32"},
1205         {Opt_debug, "debug"},
1206         {Opt_removed, "oldalloc"},
1207         {Opt_removed, "orlov"},
1208         {Opt_user_xattr, "user_xattr"},
1209         {Opt_nouser_xattr, "nouser_xattr"},
1210         {Opt_acl, "acl"},
1211         {Opt_noacl, "noacl"},
1212         {Opt_noload, "norecovery"},
1213         {Opt_noload, "noload"},
1214         {Opt_removed, "nobh"},
1215         {Opt_removed, "bh"},
1216         {Opt_commit, "commit=%u"},
1217         {Opt_min_batch_time, "min_batch_time=%u"},
1218         {Opt_max_batch_time, "max_batch_time=%u"},
1219         {Opt_journal_dev, "journal_dev=%u"},
1220         {Opt_journal_checksum, "journal_checksum"},
1221         {Opt_journal_async_commit, "journal_async_commit"},
1222         {Opt_abort, "abort"},
1223         {Opt_data_journal, "data=journal"},
1224         {Opt_data_ordered, "data=ordered"},
1225         {Opt_data_writeback, "data=writeback"},
1226         {Opt_data_err_abort, "data_err=abort"},
1227         {Opt_data_err_ignore, "data_err=ignore"},
1228         {Opt_offusrjquota, "usrjquota="},
1229         {Opt_usrjquota, "usrjquota=%s"},
1230         {Opt_offgrpjquota, "grpjquota="},
1231         {Opt_grpjquota, "grpjquota=%s"},
1232         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1233         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1234         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1235         {Opt_grpquota, "grpquota"},
1236         {Opt_noquota, "noquota"},
1237         {Opt_quota, "quota"},
1238         {Opt_usrquota, "usrquota"},
1239         {Opt_barrier, "barrier=%u"},
1240         {Opt_barrier, "barrier"},
1241         {Opt_nobarrier, "nobarrier"},
1242         {Opt_i_version, "i_version"},
1243         {Opt_stripe, "stripe=%u"},
1244         {Opt_delalloc, "delalloc"},
1245         {Opt_nodelalloc, "nodelalloc"},
1246         {Opt_mblk_io_submit, "mblk_io_submit"},
1247         {Opt_nomblk_io_submit, "nomblk_io_submit"},
1248         {Opt_block_validity, "block_validity"},
1249         {Opt_noblock_validity, "noblock_validity"},
1250         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1251         {Opt_journal_ioprio, "journal_ioprio=%u"},
1252         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1253         {Opt_auto_da_alloc, "auto_da_alloc"},
1254         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1255         {Opt_dioread_nolock, "dioread_nolock"},
1256         {Opt_dioread_lock, "dioread_lock"},
1257         {Opt_discard, "discard"},
1258         {Opt_nodiscard, "nodiscard"},
1259         {Opt_init_itable, "init_itable=%u"},
1260         {Opt_init_itable, "init_itable"},
1261         {Opt_noinit_itable, "noinit_itable"},
1262         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1263         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1264         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1265         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1266         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1267         {Opt_err, NULL},
1268 };
1269
1270 static ext4_fsblk_t get_sb_block(void **data)
1271 {
1272         ext4_fsblk_t    sb_block;
1273         char            *options = (char *) *data;
1274
1275         if (!options || strncmp(options, "sb=", 3) != 0)
1276                 return 1;       /* Default location */
1277
1278         options += 3;
1279         /* TODO: use simple_strtoll with >32bit ext4 */
1280         sb_block = simple_strtoul(options, &options, 0);
1281         if (*options && *options != ',') {
1282                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1283                        (char *) *data);
1284                 return 1;
1285         }
1286         if (*options == ',')
1287                 options++;
1288         *data = (void *) options;
1289
1290         return sb_block;
1291 }
1292
1293 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1294 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1295         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1296
1297 #ifdef CONFIG_QUOTA
1298 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1299 {
1300         struct ext4_sb_info *sbi = EXT4_SB(sb);
1301         char *qname;
1302
1303         if (sb_any_quota_loaded(sb) &&
1304                 !sbi->s_qf_names[qtype]) {
1305                 ext4_msg(sb, KERN_ERR,
1306                         "Cannot change journaled "
1307                         "quota options when quota turned on");
1308                 return -1;
1309         }
1310         qname = match_strdup(args);
1311         if (!qname) {
1312                 ext4_msg(sb, KERN_ERR,
1313                         "Not enough memory for storing quotafile name");
1314                 return -1;
1315         }
1316         if (sbi->s_qf_names[qtype] &&
1317                 strcmp(sbi->s_qf_names[qtype], qname)) {
1318                 ext4_msg(sb, KERN_ERR,
1319                         "%s quota file already specified", QTYPE2NAME(qtype));
1320                 kfree(qname);
1321                 return -1;
1322         }
1323         sbi->s_qf_names[qtype] = qname;
1324         if (strchr(sbi->s_qf_names[qtype], '/')) {
1325                 ext4_msg(sb, KERN_ERR,
1326                         "quotafile must be on filesystem root");
1327                 kfree(sbi->s_qf_names[qtype]);
1328                 sbi->s_qf_names[qtype] = NULL;
1329                 return -1;
1330         }
1331         set_opt(sb, QUOTA);
1332         return 1;
1333 }
1334
1335 static int clear_qf_name(struct super_block *sb, int qtype)
1336 {
1337
1338         struct ext4_sb_info *sbi = EXT4_SB(sb);
1339
1340         if (sb_any_quota_loaded(sb) &&
1341                 sbi->s_qf_names[qtype]) {
1342                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1343                         " when quota turned on");
1344                 return -1;
1345         }
1346         /*
1347          * The space will be released later when all options are confirmed
1348          * to be correct
1349          */
1350         sbi->s_qf_names[qtype] = NULL;
1351         return 1;
1352 }
1353 #endif
1354
1355 #define MOPT_SET        0x0001
1356 #define MOPT_CLEAR      0x0002
1357 #define MOPT_NOSUPPORT  0x0004
1358 #define MOPT_EXPLICIT   0x0008
1359 #define MOPT_CLEAR_ERR  0x0010
1360 #define MOPT_GTE0       0x0020
1361 #ifdef CONFIG_QUOTA
1362 #define MOPT_Q          0
1363 #define MOPT_QFMT       0x0040
1364 #else
1365 #define MOPT_Q          MOPT_NOSUPPORT
1366 #define MOPT_QFMT       MOPT_NOSUPPORT
1367 #endif
1368 #define MOPT_DATAJ      0x0080
1369
1370 static const struct mount_opts {
1371         int     token;
1372         int     mount_opt;
1373         int     flags;
1374 } ext4_mount_opts[] = {
1375         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1376         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1377         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1378         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1379         {Opt_mblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_SET},
1380         {Opt_nomblk_io_submit, EXT4_MOUNT_MBLK_IO_SUBMIT, MOPT_CLEAR},
1381         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1382         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1383         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_SET},
1384         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_CLEAR},
1385         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1386         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1387         {Opt_delalloc, EXT4_MOUNT_DELALLOC, MOPT_SET | MOPT_EXPLICIT},
1388         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC, MOPT_CLEAR | MOPT_EXPLICIT},
1389         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM, MOPT_SET},
1390         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1391                                     EXT4_MOUNT_JOURNAL_CHECKSUM), MOPT_SET},
1392         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_SET},
1393         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1394         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1395         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1396         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_SET},
1397         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_CLEAR},
1398         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1399         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1400         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1401         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1402         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1403         {Opt_commit, 0, MOPT_GTE0},
1404         {Opt_max_batch_time, 0, MOPT_GTE0},
1405         {Opt_min_batch_time, 0, MOPT_GTE0},
1406         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1407         {Opt_init_itable, 0, MOPT_GTE0},
1408         {Opt_stripe, 0, MOPT_GTE0},
1409         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_DATAJ},
1410         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_DATAJ},
1411         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA, MOPT_DATAJ},
1412 #ifdef CONFIG_EXT4_FS_XATTR
1413         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1414         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1415 #else
1416         {Opt_user_xattr, 0, MOPT_NOSUPPORT},
1417         {Opt_nouser_xattr, 0, MOPT_NOSUPPORT},
1418 #endif
1419 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1420         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1421         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1422 #else
1423         {Opt_acl, 0, MOPT_NOSUPPORT},
1424         {Opt_noacl, 0, MOPT_NOSUPPORT},
1425 #endif
1426         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1427         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1428         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1429         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1430                                                         MOPT_SET | MOPT_Q},
1431         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1432                                                         MOPT_SET | MOPT_Q},
1433         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1434                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1435         {Opt_usrjquota, 0, MOPT_Q},
1436         {Opt_grpjquota, 0, MOPT_Q},
1437         {Opt_offusrjquota, 0, MOPT_Q},
1438         {Opt_offgrpjquota, 0, MOPT_Q},
1439         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1440         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1441         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1442         {Opt_err, 0, 0}
1443 };
1444
1445 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1446                             substring_t *args, unsigned long *journal_devnum,
1447                             unsigned int *journal_ioprio, int is_remount)
1448 {
1449         struct ext4_sb_info *sbi = EXT4_SB(sb);
1450         const struct mount_opts *m;
1451         int arg = 0;
1452
1453 #ifdef CONFIG_QUOTA
1454         if (token == Opt_usrjquota)
1455                 return set_qf_name(sb, USRQUOTA, &args[0]);
1456         else if (token == Opt_grpjquota)
1457                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1458         else if (token == Opt_offusrjquota)
1459                 return clear_qf_name(sb, USRQUOTA);
1460         else if (token == Opt_offgrpjquota)
1461                 return clear_qf_name(sb, GRPQUOTA);
1462 #endif
1463         if (args->from && match_int(args, &arg))
1464                 return -1;
1465         switch (token) {
1466         case Opt_noacl:
1467         case Opt_nouser_xattr:
1468                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1469                 break;
1470         case Opt_sb:
1471                 return 1;       /* handled by get_sb_block() */
1472         case Opt_removed:
1473                 ext4_msg(sb, KERN_WARNING,
1474                          "Ignoring removed %s option", opt);
1475                 return 1;
1476         case Opt_resuid:
1477                 sbi->s_resuid = arg;
1478                 return 1;
1479         case Opt_resgid:
1480                 sbi->s_resgid = arg;
1481                 return 1;
1482         case Opt_abort:
1483                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1484                 return 1;
1485         case Opt_i_version:
1486                 sb->s_flags |= MS_I_VERSION;
1487                 return 1;
1488         case Opt_journal_dev:
1489                 if (is_remount) {
1490                         ext4_msg(sb, KERN_ERR,
1491                                  "Cannot specify journal on remount");
1492                         return -1;
1493                 }
1494                 *journal_devnum = arg;
1495                 return 1;
1496         case Opt_journal_ioprio:
1497                 if (arg < 0 || arg > 7)
1498                         return -1;
1499                 *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1500                 return 1;
1501         }
1502
1503         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1504                 if (token != m->token)
1505                         continue;
1506                 if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1507                         return -1;
1508                 if (m->flags & MOPT_EXPLICIT)
1509                         set_opt2(sb, EXPLICIT_DELALLOC);
1510                 if (m->flags & MOPT_CLEAR_ERR)
1511                         clear_opt(sb, ERRORS_MASK);
1512                 if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1513                         ext4_msg(sb, KERN_ERR, "Cannot change quota "
1514                                  "options when quota turned on");
1515                         return -1;
1516                 }
1517
1518                 if (m->flags & MOPT_NOSUPPORT) {
1519                         ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1520                 } else if (token == Opt_commit) {
1521                         if (arg == 0)
1522                                 arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1523                         sbi->s_commit_interval = HZ * arg;
1524                 } else if (token == Opt_max_batch_time) {
1525                         if (arg == 0)
1526                                 arg = EXT4_DEF_MAX_BATCH_TIME;
1527                         sbi->s_max_batch_time = arg;
1528                 } else if (token == Opt_min_batch_time) {
1529                         sbi->s_min_batch_time = arg;
1530                 } else if (token == Opt_inode_readahead_blks) {
1531                         if (arg > (1 << 30))
1532                                 return -1;
1533                         if (arg && !is_power_of_2(arg)) {
1534                                 ext4_msg(sb, KERN_ERR,
1535                                          "EXT4-fs: inode_readahead_blks"
1536                                          " must be a power of 2");
1537                                 return -1;
1538                         }
1539                         sbi->s_inode_readahead_blks = arg;
1540                 } else if (token == Opt_init_itable) {
1541                         set_opt(sb, INIT_INODE_TABLE);
1542                         if (!args->from)
1543                                 arg = EXT4_DEF_LI_WAIT_MULT;
1544                         sbi->s_li_wait_mult = arg;
1545                 } else if (token == Opt_stripe) {
1546                         sbi->s_stripe = arg;
1547                 } else if (m->flags & MOPT_DATAJ) {
1548                         if (is_remount) {
1549                                 if (!sbi->s_journal)
1550                                         ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1551                                 else if (test_opt(sb, DATA_FLAGS) !=
1552                                          m->mount_opt) {
1553                                         ext4_msg(sb, KERN_ERR,
1554                                          "Cannot change data mode on remount");
1555                                         return -1;
1556                                 }
1557                         } else {
1558                                 clear_opt(sb, DATA_FLAGS);
1559                                 sbi->s_mount_opt |= m->mount_opt;
1560                         }
1561 #ifdef CONFIG_QUOTA
1562                 } else if (m->flags & MOPT_QFMT) {
1563                         if (sb_any_quota_loaded(sb) &&
1564                             sbi->s_jquota_fmt != m->mount_opt) {
1565                                 ext4_msg(sb, KERN_ERR, "Cannot "
1566                                          "change journaled quota options "
1567                                          "when quota turned on");
1568                                 return -1;
1569                         }
1570                         sbi->s_jquota_fmt = m->mount_opt;
1571 #endif
1572                 } else {
1573                         if (!args->from)
1574                                 arg = 1;
1575                         if (m->flags & MOPT_CLEAR)
1576                                 arg = !arg;
1577                         else if (unlikely(!(m->flags & MOPT_SET))) {
1578                                 ext4_msg(sb, KERN_WARNING,
1579                                          "buggy handling of option %s", opt);
1580                                 WARN_ON(1);
1581                                 return -1;
1582                         }
1583                         if (arg != 0)
1584                                 sbi->s_mount_opt |= m->mount_opt;
1585                         else
1586                                 sbi->s_mount_opt &= ~m->mount_opt;
1587                 }
1588                 return 1;
1589         }
1590         ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1591                  "or missing value", opt);
1592         return -1;
1593 }
1594
1595 static int parse_options(char *options, struct super_block *sb,
1596                          unsigned long *journal_devnum,
1597                          unsigned int *journal_ioprio,
1598                          int is_remount)
1599 {
1600         struct ext4_sb_info *sbi = EXT4_SB(sb);
1601         char *p;
1602         substring_t args[MAX_OPT_ARGS];
1603         int token;
1604
1605         if (!options)
1606                 return 1;
1607
1608         while ((p = strsep(&options, ",")) != NULL) {
1609                 if (!*p)
1610                         continue;
1611                 /*
1612                  * Initialize args struct so we know whether arg was
1613                  * found; some options take optional arguments.
1614                  */
1615                 args[0].to = args[0].from = 0;
1616                 token = match_token(p, tokens, args);
1617                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1618                                      journal_ioprio, is_remount) < 0)
1619                         return 0;
1620         }
1621 #ifdef CONFIG_QUOTA
1622         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1623                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1624                         clear_opt(sb, USRQUOTA);
1625
1626                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1627                         clear_opt(sb, GRPQUOTA);
1628
1629                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1630                         ext4_msg(sb, KERN_ERR, "old and new quota "
1631                                         "format mixing");
1632                         return 0;
1633                 }
1634
1635                 if (!sbi->s_jquota_fmt) {
1636                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1637                                         "not specified");
1638                         return 0;
1639                 }
1640         } else {
1641                 if (sbi->s_jquota_fmt) {
1642                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1643                                         "specified with no journaling "
1644                                         "enabled");
1645                         return 0;
1646                 }
1647         }
1648 #endif
1649         return 1;
1650 }
1651
1652 static inline void ext4_show_quota_options(struct seq_file *seq,
1653                                            struct super_block *sb)
1654 {
1655 #if defined(CONFIG_QUOTA)
1656         struct ext4_sb_info *sbi = EXT4_SB(sb);
1657
1658         if (sbi->s_jquota_fmt) {
1659                 char *fmtname = "";
1660
1661                 switch (sbi->s_jquota_fmt) {
1662                 case QFMT_VFS_OLD:
1663                         fmtname = "vfsold";
1664                         break;
1665                 case QFMT_VFS_V0:
1666                         fmtname = "vfsv0";
1667                         break;
1668                 case QFMT_VFS_V1:
1669                         fmtname = "vfsv1";
1670                         break;
1671                 }
1672                 seq_printf(seq, ",jqfmt=%s", fmtname);
1673         }
1674
1675         if (sbi->s_qf_names[USRQUOTA])
1676                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1677
1678         if (sbi->s_qf_names[GRPQUOTA])
1679                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1680
1681         if (test_opt(sb, USRQUOTA))
1682                 seq_puts(seq, ",usrquota");
1683
1684         if (test_opt(sb, GRPQUOTA))
1685                 seq_puts(seq, ",grpquota");
1686 #endif
1687 }
1688
1689 static const char *token2str(int token)
1690 {
1691         static const struct match_token *t;
1692
1693         for (t = tokens; t->token != Opt_err; t++)
1694                 if (t->token == token && !strchr(t->pattern, '='))
1695                         break;
1696         return t->pattern;
1697 }
1698
1699 /*
1700  * Show an option if
1701  *  - it's set to a non-default value OR
1702  *  - if the per-sb default is different from the global default
1703  */
1704 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1705                               int nodefs)
1706 {
1707         struct ext4_sb_info *sbi = EXT4_SB(sb);
1708         struct ext4_super_block *es = sbi->s_es;
1709         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1710         const struct mount_opts *m;
1711         char sep = nodefs ? '\n' : ',';
1712
1713 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1714 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1715
1716         if (sbi->s_sb_block != 1)
1717                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1718
1719         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1720                 int want_set = m->flags & MOPT_SET;
1721                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1722                     (m->flags & MOPT_CLEAR_ERR))
1723                         continue;
1724                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1725                         continue; /* skip if same as the default */
1726                 if ((want_set &&
1727                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1728                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1729                         continue; /* select Opt_noFoo vs Opt_Foo */
1730                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1731         }
1732
1733         if (nodefs || sbi->s_resuid != EXT4_DEF_RESUID ||
1734             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1735                 SEQ_OPTS_PRINT("resuid=%u", sbi->s_resuid);
1736         if (nodefs || sbi->s_resgid != EXT4_DEF_RESGID ||
1737             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1738                 SEQ_OPTS_PRINT("resgid=%u", sbi->s_resgid);
1739         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1740         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1741                 SEQ_OPTS_PUTS("errors=remount-ro");
1742         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1743                 SEQ_OPTS_PUTS("errors=continue");
1744         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1745                 SEQ_OPTS_PUTS("errors=panic");
1746         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1747                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1748         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1749                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1750         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1751                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1752         if (sb->s_flags & MS_I_VERSION)
1753                 SEQ_OPTS_PUTS("i_version");
1754         if (nodefs || sbi->s_stripe)
1755                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1756         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1757                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1758                         SEQ_OPTS_PUTS("data=journal");
1759                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1760                         SEQ_OPTS_PUTS("data=ordered");
1761                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1762                         SEQ_OPTS_PUTS("data=writeback");
1763         }
1764         if (nodefs ||
1765             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1766                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1767                                sbi->s_inode_readahead_blks);
1768
1769         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1770                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1771                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1772
1773         ext4_show_quota_options(seq, sb);
1774         return 0;
1775 }
1776
1777 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1778 {
1779         return _ext4_show_options(seq, root->d_sb, 0);
1780 }
1781
1782 static int options_seq_show(struct seq_file *seq, void *offset)
1783 {
1784         struct super_block *sb = seq->private;
1785         int rc;
1786
1787         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1788         rc = _ext4_show_options(seq, sb, 1);
1789         seq_puts(seq, "\n");
1790         return rc;
1791 }
1792
1793 static int options_open_fs(struct inode *inode, struct file *file)
1794 {
1795         return single_open(file, options_seq_show, PDE(inode)->data);
1796 }
1797
1798 static const struct file_operations ext4_seq_options_fops = {
1799         .owner = THIS_MODULE,
1800         .open = options_open_fs,
1801         .read = seq_read,
1802         .llseek = seq_lseek,
1803         .release = single_release,
1804 };
1805
1806 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1807                             int read_only)
1808 {
1809         struct ext4_sb_info *sbi = EXT4_SB(sb);
1810         int res = 0;
1811
1812         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1813                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1814                          "forcing read-only mode");
1815                 res = MS_RDONLY;
1816         }
1817         if (read_only)
1818                 goto done;
1819         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1820                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1821                          "running e2fsck is recommended");
1822         else if ((sbi->s_mount_state & EXT4_ERROR_FS))
1823                 ext4_msg(sb, KERN_WARNING,
1824                          "warning: mounting fs with errors, "
1825                          "running e2fsck is recommended");
1826         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1827                  le16_to_cpu(es->s_mnt_count) >=
1828                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1829                 ext4_msg(sb, KERN_WARNING,
1830                          "warning: maximal mount count reached, "
1831                          "running e2fsck is recommended");
1832         else if (le32_to_cpu(es->s_checkinterval) &&
1833                 (le32_to_cpu(es->s_lastcheck) +
1834                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1835                 ext4_msg(sb, KERN_WARNING,
1836                          "warning: checktime reached, "
1837                          "running e2fsck is recommended");
1838         if (!sbi->s_journal)
1839                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1840         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1841                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1842         le16_add_cpu(&es->s_mnt_count, 1);
1843         es->s_mtime = cpu_to_le32(get_seconds());
1844         ext4_update_dynamic_rev(sb);
1845         if (sbi->s_journal)
1846                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1847
1848         ext4_commit_super(sb, 1);
1849 done:
1850         if (test_opt(sb, DEBUG))
1851                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1852                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1853                         sb->s_blocksize,
1854                         sbi->s_groups_count,
1855                         EXT4_BLOCKS_PER_GROUP(sb),
1856                         EXT4_INODES_PER_GROUP(sb),
1857                         sbi->s_mount_opt, sbi->s_mount_opt2);
1858
1859         cleancache_init_fs(sb);
1860         return res;
1861 }
1862
1863 static int ext4_fill_flex_info(struct super_block *sb)
1864 {
1865         struct ext4_sb_info *sbi = EXT4_SB(sb);
1866         struct ext4_group_desc *gdp = NULL;
1867         ext4_group_t flex_group_count;
1868         ext4_group_t flex_group;
1869         unsigned int groups_per_flex = 0;
1870         size_t size;
1871         int i;
1872
1873         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1874         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1875                 sbi->s_log_groups_per_flex = 0;
1876                 return 1;
1877         }
1878         groups_per_flex = 1 << sbi->s_log_groups_per_flex;
1879
1880         /* We allocate both existing and potentially added groups */
1881         flex_group_count = ((sbi->s_groups_count + groups_per_flex - 1) +
1882                         ((le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) + 1) <<
1883                               EXT4_DESC_PER_BLOCK_BITS(sb))) / groups_per_flex;
1884         size = flex_group_count * sizeof(struct flex_groups);
1885         sbi->s_flex_groups = ext4_kvzalloc(size, GFP_KERNEL);
1886         if (sbi->s_flex_groups == NULL) {
1887                 ext4_msg(sb, KERN_ERR, "not enough memory for %u flex groups",
1888                          flex_group_count);
1889                 goto failed;
1890         }
1891
1892         for (i = 0; i < sbi->s_groups_count; i++) {
1893                 gdp = ext4_get_group_desc(sb, i, NULL);
1894
1895                 flex_group = ext4_flex_group(sbi, i);
1896                 atomic_add(ext4_free_inodes_count(sb, gdp),
1897                            &sbi->s_flex_groups[flex_group].free_inodes);
1898                 atomic_add(ext4_free_group_clusters(sb, gdp),
1899                            &sbi->s_flex_groups[flex_group].free_clusters);
1900                 atomic_add(ext4_used_dirs_count(sb, gdp),
1901                            &sbi->s_flex_groups[flex_group].used_dirs);
1902         }
1903
1904         return 1;
1905 failed:
1906         return 0;
1907 }
1908
1909 __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1910                             struct ext4_group_desc *gdp)
1911 {
1912         __u16 crc = 0;
1913
1914         if (sbi->s_es->s_feature_ro_compat &
1915             cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
1916                 int offset = offsetof(struct ext4_group_desc, bg_checksum);
1917                 __le32 le_group = cpu_to_le32(block_group);
1918
1919                 crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
1920                 crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
1921                 crc = crc16(crc, (__u8 *)gdp, offset);
1922                 offset += sizeof(gdp->bg_checksum); /* skip checksum */
1923                 /* for checksum of struct ext4_group_desc do the rest...*/
1924                 if ((sbi->s_es->s_feature_incompat &
1925                      cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
1926                     offset < le16_to_cpu(sbi->s_es->s_desc_size))
1927                         crc = crc16(crc, (__u8 *)gdp + offset,
1928                                     le16_to_cpu(sbi->s_es->s_desc_size) -
1929                                         offset);
1930         }
1931
1932         return cpu_to_le16(crc);
1933 }
1934
1935 int ext4_group_desc_csum_verify(struct ext4_sb_info *sbi, __u32 block_group,
1936                                 struct ext4_group_desc *gdp)
1937 {
1938         if ((sbi->s_es->s_feature_ro_compat &
1939              cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) &&
1940             (gdp->bg_checksum != ext4_group_desc_csum(sbi, block_group, gdp)))
1941                 return 0;
1942
1943         return 1;
1944 }
1945
1946 /* Called at mount-time, super-block is locked */
1947 static int ext4_check_descriptors(struct super_block *sb,
1948                                   ext4_group_t *first_not_zeroed)
1949 {
1950         struct ext4_sb_info *sbi = EXT4_SB(sb);
1951         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
1952         ext4_fsblk_t last_block;
1953         ext4_fsblk_t block_bitmap;
1954         ext4_fsblk_t inode_bitmap;
1955         ext4_fsblk_t inode_table;
1956         int flexbg_flag = 0;
1957         ext4_group_t i, grp = sbi->s_groups_count;
1958
1959         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
1960                 flexbg_flag = 1;
1961
1962         ext4_debug("Checking group descriptors");
1963
1964         for (i = 0; i < sbi->s_groups_count; i++) {
1965                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
1966
1967                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
1968                         last_block = ext4_blocks_count(sbi->s_es) - 1;
1969                 else
1970                         last_block = first_block +
1971                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
1972
1973                 if ((grp == sbi->s_groups_count) &&
1974                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
1975                         grp = i;
1976
1977                 block_bitmap = ext4_block_bitmap(sb, gdp);
1978                 if (block_bitmap < first_block || block_bitmap > last_block) {
1979                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1980                                "Block bitmap for group %u not in group "
1981                                "(block %llu)!", i, block_bitmap);
1982                         return 0;
1983                 }
1984                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
1985                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
1986                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1987                                "Inode bitmap for group %u not in group "
1988                                "(block %llu)!", i, inode_bitmap);
1989                         return 0;
1990                 }
1991                 inode_table = ext4_inode_table(sb, gdp);
1992                 if (inode_table < first_block ||
1993                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
1994                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
1995                                "Inode table for group %u not in group "
1996                                "(block %llu)!", i, inode_table);
1997                         return 0;
1998                 }
1999                 ext4_lock_group(sb, i);
2000                 if (!ext4_group_desc_csum_verify(sbi, i, gdp)) {
2001                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2002                                  "Checksum for group %u failed (%u!=%u)",
2003                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2004                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2005                         if (!(sb->s_flags & MS_RDONLY)) {
2006                                 ext4_unlock_group(sb, i);
2007                                 return 0;
2008                         }
2009                 }
2010                 ext4_unlock_group(sb, i);
2011                 if (!flexbg_flag)
2012                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2013         }
2014         if (NULL != first_not_zeroed)
2015                 *first_not_zeroed = grp;
2016
2017         ext4_free_blocks_count_set(sbi->s_es,
2018                                    EXT4_C2B(sbi, ext4_count_free_clusters(sb)));
2019         sbi->s_es->s_free_inodes_count =cpu_to_le32(ext4_count_free_inodes(sb));
2020         return 1;
2021 }
2022
2023 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2024  * the superblock) which were deleted from all directories, but held open by
2025  * a process at the time of a crash.  We walk the list and try to delete these
2026  * inodes at recovery time (only with a read-write filesystem).
2027  *
2028  * In order to keep the orphan inode chain consistent during traversal (in
2029  * case of crash during recovery), we link each inode into the superblock
2030  * orphan list_head and handle it the same way as an inode deletion during
2031  * normal operation (which journals the operations for us).
2032  *
2033  * We only do an iget() and an iput() on each inode, which is very safe if we
2034  * accidentally point at an in-use or already deleted inode.  The worst that
2035  * can happen in this case is that we get a "bit already cleared" message from
2036  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2037  * e2fsck was run on this filesystem, and it must have already done the orphan
2038  * inode cleanup for us, so we can safely abort without any further action.
2039  */
2040 static void ext4_orphan_cleanup(struct super_block *sb,
2041                                 struct ext4_super_block *es)
2042 {
2043         unsigned int s_flags = sb->s_flags;
2044         int nr_orphans = 0, nr_truncates = 0;
2045 #ifdef CONFIG_QUOTA
2046         int i;
2047 #endif
2048         if (!es->s_last_orphan) {
2049                 jbd_debug(4, "no orphan inodes to clean up\n");
2050                 return;
2051         }
2052
2053         if (bdev_read_only(sb->s_bdev)) {
2054                 ext4_msg(sb, KERN_ERR, "write access "
2055                         "unavailable, skipping orphan cleanup");
2056                 return;
2057         }
2058
2059         /* Check if feature set would not allow a r/w mount */
2060         if (!ext4_feature_set_ok(sb, 0)) {
2061                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2062                          "unknown ROCOMPAT features");
2063                 return;
2064         }
2065
2066         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2067                 if (es->s_last_orphan)
2068                         jbd_debug(1, "Errors on filesystem, "
2069                                   "clearing orphan list.\n");
2070                 es->s_last_orphan = 0;
2071                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2072                 return;
2073         }
2074
2075         if (s_flags & MS_RDONLY) {
2076                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2077                 sb->s_flags &= ~MS_RDONLY;
2078         }
2079 #ifdef CONFIG_QUOTA
2080         /* Needed for iput() to work correctly and not trash data */
2081         sb->s_flags |= MS_ACTIVE;
2082         /* Turn on quotas so that they are updated correctly */
2083         for (i = 0; i < MAXQUOTAS; i++) {
2084                 if (EXT4_SB(sb)->s_qf_names[i]) {
2085                         int ret = ext4_quota_on_mount(sb, i);
2086                         if (ret < 0)
2087                                 ext4_msg(sb, KERN_ERR,
2088                                         "Cannot turn on journaled "
2089                                         "quota: error %d", ret);
2090                 }
2091         }
2092 #endif
2093
2094         while (es->s_last_orphan) {
2095                 struct inode *inode;
2096
2097                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2098                 if (IS_ERR(inode)) {
2099                         es->s_last_orphan = 0;
2100                         break;
2101                 }
2102
2103                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2104                 dquot_initialize(inode);
2105                 if (inode->i_nlink) {
2106                         ext4_msg(sb, KERN_DEBUG,
2107                                 "%s: truncating inode %lu to %lld bytes",
2108                                 __func__, inode->i_ino, inode->i_size);
2109                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2110                                   inode->i_ino, inode->i_size);
2111                         ext4_truncate(inode);
2112                         nr_truncates++;
2113                 } else {
2114                         ext4_msg(sb, KERN_DEBUG,
2115                                 "%s: deleting unreferenced inode %lu",
2116                                 __func__, inode->i_ino);
2117                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2118                                   inode->i_ino);
2119                         nr_orphans++;
2120                 }
2121                 iput(inode);  /* The delete magic happens here! */
2122         }
2123
2124 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2125
2126         if (nr_orphans)
2127                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2128                        PLURAL(nr_orphans));
2129         if (nr_truncates)
2130                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2131                        PLURAL(nr_truncates));
2132 #ifdef CONFIG_QUOTA
2133         /* Turn quotas off */
2134         for (i = 0; i < MAXQUOTAS; i++) {
2135                 if (sb_dqopt(sb)->files[i])
2136                         dquot_quota_off(sb, i);
2137         }
2138 #endif
2139         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2140 }
2141
2142 /*
2143  * Maximal extent format file size.
2144  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2145  * extent format containers, within a sector_t, and within i_blocks
2146  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2147  * so that won't be a limiting factor.
2148  *
2149  * However there is other limiting factor. We do store extents in the form
2150  * of starting block and length, hence the resulting length of the extent
2151  * covering maximum file size must fit into on-disk format containers as
2152  * well. Given that length is always by 1 unit bigger than max unit (because
2153  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2154  *
2155  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2156  */
2157 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2158 {
2159         loff_t res;
2160         loff_t upper_limit = MAX_LFS_FILESIZE;
2161
2162         /* small i_blocks in vfs inode? */
2163         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2164                 /*
2165                  * CONFIG_LBDAF is not enabled implies the inode
2166                  * i_block represent total blocks in 512 bytes
2167                  * 32 == size of vfs inode i_blocks * 8
2168                  */
2169                 upper_limit = (1LL << 32) - 1;
2170
2171                 /* total blocks in file system block size */
2172                 upper_limit >>= (blkbits - 9);
2173                 upper_limit <<= blkbits;
2174         }
2175
2176         /*
2177          * 32-bit extent-start container, ee_block. We lower the maxbytes
2178          * by one fs block, so ee_len can cover the extent of maximum file
2179          * size
2180          */
2181         res = (1LL << 32) - 1;
2182         res <<= blkbits;
2183
2184         /* Sanity check against vm- & vfs- imposed limits */
2185         if (res > upper_limit)
2186                 res = upper_limit;
2187
2188         return res;
2189 }
2190
2191 /*
2192  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2193  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2194  * We need to be 1 filesystem block less than the 2^48 sector limit.
2195  */
2196 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2197 {
2198         loff_t res = EXT4_NDIR_BLOCKS;
2199         int meta_blocks;
2200         loff_t upper_limit;
2201         /* This is calculated to be the largest file size for a dense, block
2202          * mapped file such that the file's total number of 512-byte sectors,
2203          * including data and all indirect blocks, does not exceed (2^48 - 1).
2204          *
2205          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2206          * number of 512-byte sectors of the file.
2207          */
2208
2209         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2210                 /*
2211                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2212                  * the inode i_block field represents total file blocks in
2213                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2214                  */
2215                 upper_limit = (1LL << 32) - 1;
2216
2217                 /* total blocks in file system block size */
2218                 upper_limit >>= (bits - 9);
2219
2220         } else {
2221                 /*
2222                  * We use 48 bit ext4_inode i_blocks
2223                  * With EXT4_HUGE_FILE_FL set the i_blocks
2224                  * represent total number of blocks in
2225                  * file system block size
2226                  */
2227                 upper_limit = (1LL << 48) - 1;
2228
2229         }
2230
2231         /* indirect blocks */
2232         meta_blocks = 1;
2233         /* double indirect blocks */
2234         meta_blocks += 1 + (1LL << (bits-2));
2235         /* tripple indirect blocks */
2236         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2237
2238         upper_limit -= meta_blocks;
2239         upper_limit <<= bits;
2240
2241         res += 1LL << (bits-2);
2242         res += 1LL << (2*(bits-2));
2243         res += 1LL << (3*(bits-2));
2244         res <<= bits;
2245         if (res > upper_limit)
2246                 res = upper_limit;
2247
2248         if (res > MAX_LFS_FILESIZE)
2249                 res = MAX_LFS_FILESIZE;
2250
2251         return res;
2252 }
2253
2254 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2255                                    ext4_fsblk_t logical_sb_block, int nr)
2256 {
2257         struct ext4_sb_info *sbi = EXT4_SB(sb);
2258         ext4_group_t bg, first_meta_bg;
2259         int has_super = 0;
2260
2261         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2262
2263         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2264             nr < first_meta_bg)
2265                 return logical_sb_block + nr + 1;
2266         bg = sbi->s_desc_per_block * nr;
2267         if (ext4_bg_has_super(sb, bg))
2268                 has_super = 1;
2269
2270         return (has_super + ext4_group_first_block_no(sb, bg));
2271 }
2272
2273 /**
2274  * ext4_get_stripe_size: Get the stripe size.
2275  * @sbi: In memory super block info
2276  *
2277  * If we have specified it via mount option, then
2278  * use the mount option value. If the value specified at mount time is
2279  * greater than the blocks per group use the super block value.
2280  * If the super block value is greater than blocks per group return 0.
2281  * Allocator needs it be less than blocks per group.
2282  *
2283  */
2284 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2285 {
2286         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2287         unsigned long stripe_width =
2288                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2289         int ret;
2290
2291         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2292                 ret = sbi->s_stripe;
2293         else if (stripe_width <= sbi->s_blocks_per_group)
2294                 ret = stripe_width;
2295         else if (stride <= sbi->s_blocks_per_group)
2296                 ret = stride;
2297         else
2298                 ret = 0;
2299
2300         /*
2301          * If the stripe width is 1, this makes no sense and
2302          * we set it to 0 to turn off stripe handling code.
2303          */
2304         if (ret <= 1)
2305                 ret = 0;
2306
2307         return ret;
2308 }
2309
2310 /* sysfs supprt */
2311
2312 struct ext4_attr {
2313         struct attribute attr;
2314         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2315         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2316                          const char *, size_t);
2317         int offset;
2318 };
2319
2320 static int parse_strtoul(const char *buf,
2321                 unsigned long max, unsigned long *value)
2322 {
2323         char *endp;
2324
2325         *value = simple_strtoul(skip_spaces(buf), &endp, 0);
2326         endp = skip_spaces(endp);
2327         if (*endp || *value > max)
2328                 return -EINVAL;
2329
2330         return 0;
2331 }
2332
2333 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2334                                               struct ext4_sb_info *sbi,
2335                                               char *buf)
2336 {
2337         return snprintf(buf, PAGE_SIZE, "%llu\n",
2338                 (s64) EXT4_C2B(sbi,
2339                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2340 }
2341
2342 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2343                                          struct ext4_sb_info *sbi, char *buf)
2344 {
2345         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2346
2347         if (!sb->s_bdev->bd_part)
2348                 return snprintf(buf, PAGE_SIZE, "0\n");
2349         return snprintf(buf, PAGE_SIZE, "%lu\n",
2350                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2351                          sbi->s_sectors_written_start) >> 1);
2352 }
2353
2354 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2355                                           struct ext4_sb_info *sbi, char *buf)
2356 {
2357         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2358
2359         if (!sb->s_bdev->bd_part)
2360                 return snprintf(buf, PAGE_SIZE, "0\n");
2361         return snprintf(buf, PAGE_SIZE, "%llu\n",
2362                         (unsigned long long)(sbi->s_kbytes_written +
2363                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2364                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2365 }
2366
2367 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2368                                           struct ext4_sb_info *sbi,
2369                                           const char *buf, size_t count)
2370 {
2371         unsigned long t;
2372
2373         if (parse_strtoul(buf, 0x40000000, &t))
2374                 return -EINVAL;
2375
2376         if (t && !is_power_of_2(t))
2377                 return -EINVAL;
2378
2379         sbi->s_inode_readahead_blks = t;
2380         return count;
2381 }
2382
2383 static ssize_t sbi_ui_show(struct ext4_attr *a,
2384                            struct ext4_sb_info *sbi, char *buf)
2385 {
2386         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2387
2388         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2389 }
2390
2391 static ssize_t sbi_ui_store(struct ext4_attr *a,
2392                             struct ext4_sb_info *sbi,
2393                             const char *buf, size_t count)
2394 {
2395         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->offset);
2396         unsigned long t;
2397
2398         if (parse_strtoul(buf, 0xffffffff, &t))
2399                 return -EINVAL;
2400         *ui = t;
2401         return count;
2402 }
2403
2404 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2405 static struct ext4_attr ext4_attr_##_name = {                   \
2406         .attr = {.name = __stringify(_name), .mode = _mode },   \
2407         .show   = _show,                                        \
2408         .store  = _store,                                       \
2409         .offset = offsetof(struct ext4_sb_info, _elname),       \
2410 }
2411 #define EXT4_ATTR(name, mode, show, store) \
2412 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2413
2414 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2415 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2416 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2417 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2418         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2419 #define ATTR_LIST(name) &ext4_attr_##name.attr
2420
2421 EXT4_RO_ATTR(delayed_allocation_blocks);
2422 EXT4_RO_ATTR(session_write_kbytes);
2423 EXT4_RO_ATTR(lifetime_write_kbytes);
2424 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2425                  inode_readahead_blks_store, s_inode_readahead_blks);
2426 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2427 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2428 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2429 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2430 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2431 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2432 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2433 EXT4_RW_ATTR_SBI_UI(max_writeback_mb_bump, s_max_writeback_mb_bump);
2434
2435 static struct attribute *ext4_attrs[] = {
2436         ATTR_LIST(delayed_allocation_blocks),
2437         ATTR_LIST(session_write_kbytes),
2438         ATTR_LIST(lifetime_write_kbytes),
2439         ATTR_LIST(inode_readahead_blks),
2440         ATTR_LIST(inode_goal),
2441         ATTR_LIST(mb_stats),
2442         ATTR_LIST(mb_max_to_scan),
2443         ATTR_LIST(mb_min_to_scan),
2444         ATTR_LIST(mb_order2_req),
2445         ATTR_LIST(mb_stream_req),
2446         ATTR_LIST(mb_group_prealloc),
2447         ATTR_LIST(max_writeback_mb_bump),
2448         NULL,
2449 };
2450
2451 /* Features this copy of ext4 supports */
2452 EXT4_INFO_ATTR(lazy_itable_init);
2453 EXT4_INFO_ATTR(batched_discard);
2454
2455 static struct attribute *ext4_feat_attrs[] = {
2456         ATTR_LIST(lazy_itable_init),
2457         ATTR_LIST(batched_discard),
2458         NULL,
2459 };
2460
2461 static ssize_t ext4_attr_show(struct kobject *kobj,
2462                               struct attribute *attr, char *buf)
2463 {
2464         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2465                                                 s_kobj);
2466         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2467
2468         return a->show ? a->show(a, sbi, buf) : 0;
2469 }
2470
2471 static ssize_t ext4_attr_store(struct kobject *kobj,
2472                                struct attribute *attr,
2473                                const char *buf, size_t len)
2474 {
2475         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2476                                                 s_kobj);
2477         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2478
2479         return a->store ? a->store(a, sbi, buf, len) : 0;
2480 }
2481
2482 static void ext4_sb_release(struct kobject *kobj)
2483 {
2484         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2485                                                 s_kobj);
2486         complete(&sbi->s_kobj_unregister);
2487 }
2488
2489 static const struct sysfs_ops ext4_attr_ops = {
2490         .show   = ext4_attr_show,
2491         .store  = ext4_attr_store,
2492 };
2493
2494 static struct kobj_type ext4_ktype = {
2495         .default_attrs  = ext4_attrs,
2496         .sysfs_ops      = &ext4_attr_ops,
2497         .release        = ext4_sb_release,
2498 };
2499
2500 static void ext4_feat_release(struct kobject *kobj)
2501 {
2502         complete(&ext4_feat->f_kobj_unregister);
2503 }
2504
2505 static struct kobj_type ext4_feat_ktype = {
2506         .default_attrs  = ext4_feat_attrs,
2507         .sysfs_ops      = &ext4_attr_ops,
2508         .release        = ext4_feat_release,
2509 };
2510
2511 /*
2512  * Check whether this filesystem can be mounted based on
2513  * the features present and the RDONLY/RDWR mount requested.
2514  * Returns 1 if this filesystem can be mounted as requested,
2515  * 0 if it cannot be.
2516  */
2517 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2518 {
2519         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2520                 ext4_msg(sb, KERN_ERR,
2521                         "Couldn't mount because of "
2522                         "unsupported optional features (%x)",
2523                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2524                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2525                 return 0;
2526         }
2527
2528         if (readonly)
2529                 return 1;
2530
2531         /* Check that feature set is OK for a read-write mount */
2532         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2533                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2534                          "unsupported optional features (%x)",
2535                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2536                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2537                 return 0;
2538         }
2539         /*
2540          * Large file size enabled file system can only be mounted
2541          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2542          */
2543         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2544                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2545                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2546                                  "cannot be mounted RDWR without "
2547                                  "CONFIG_LBDAF");
2548                         return 0;
2549                 }
2550         }
2551         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2552             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2553                 ext4_msg(sb, KERN_ERR,
2554                          "Can't support bigalloc feature without "
2555                          "extents feature\n");
2556                 return 0;
2557         }
2558         return 1;
2559 }
2560
2561 /*
2562  * This function is called once a day if we have errors logged
2563  * on the file system
2564  */
2565 static void print_daily_error_info(unsigned long arg)
2566 {
2567         struct super_block *sb = (struct super_block *) arg;
2568         struct ext4_sb_info *sbi;
2569         struct ext4_super_block *es;
2570
2571         sbi = EXT4_SB(sb);
2572         es = sbi->s_es;
2573
2574         if (es->s_error_count)
2575                 ext4_msg(sb, KERN_NOTICE, "error count: %u",
2576                          le32_to_cpu(es->s_error_count));
2577         if (es->s_first_error_time) {
2578                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at %u: %.*s:%d",
2579                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2580                        (int) sizeof(es->s_first_error_func),
2581                        es->s_first_error_func,
2582                        le32_to_cpu(es->s_first_error_line));
2583                 if (es->s_first_error_ino)
2584                         printk(": inode %u",
2585                                le32_to_cpu(es->s_first_error_ino));
2586                 if (es->s_first_error_block)
2587                         printk(": block %llu", (unsigned long long)
2588                                le64_to_cpu(es->s_first_error_block));
2589                 printk("\n");
2590         }
2591         if (es->s_last_error_time) {
2592                 printk(KERN_NOTICE "EXT4-fs (%s): last error at %u: %.*s:%d",
2593                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2594                        (int) sizeof(es->s_last_error_func),
2595                        es->s_last_error_func,
2596                        le32_to_cpu(es->s_last_error_line));
2597                 if (es->s_last_error_ino)
2598                         printk(": inode %u",
2599                                le32_to_cpu(es->s_last_error_ino));
2600                 if (es->s_last_error_block)
2601                         printk(": block %llu", (unsigned long long)
2602                                le64_to_cpu(es->s_last_error_block));
2603                 printk("\n");
2604         }
2605         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2606 }
2607
2608 /* Find next suitable group and run ext4_init_inode_table */
2609 static int ext4_run_li_request(struct ext4_li_request *elr)
2610 {
2611         struct ext4_group_desc *gdp = NULL;
2612         ext4_group_t group, ngroups;
2613         struct super_block *sb;
2614         unsigned long timeout = 0;
2615         int ret = 0;
2616
2617         sb = elr->lr_super;
2618         ngroups = EXT4_SB(sb)->s_groups_count;
2619
2620         for (group = elr->lr_next_group; group < ngroups; group++) {
2621                 gdp = ext4_get_group_desc(sb, group, NULL);
2622                 if (!gdp) {
2623                         ret = 1;
2624                         break;
2625                 }
2626
2627                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2628                         break;
2629         }
2630
2631         if (group == ngroups)
2632                 ret = 1;
2633
2634         if (!ret) {
2635                 timeout = jiffies;
2636                 ret = ext4_init_inode_table(sb, group,
2637                                             elr->lr_timeout ? 0 : 1);
2638                 if (elr->lr_timeout == 0) {
2639                         timeout = (jiffies - timeout) *
2640                                   elr->lr_sbi->s_li_wait_mult;
2641                         elr->lr_timeout = timeout;
2642                 }
2643                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2644                 elr->lr_next_group = group + 1;
2645         }
2646
2647         return ret;
2648 }
2649
2650 /*
2651  * Remove lr_request from the list_request and free the
2652  * request structure. Should be called with li_list_mtx held
2653  */
2654 static void ext4_remove_li_request(struct ext4_li_request *elr)
2655 {
2656         struct ext4_sb_info *sbi;
2657
2658         if (!elr)
2659                 return;
2660
2661         sbi = elr->lr_sbi;
2662
2663         list_del(&elr->lr_request);
2664         sbi->s_li_request = NULL;
2665         kfree(elr);
2666 }
2667
2668 static void ext4_unregister_li_request(struct super_block *sb)
2669 {
2670         mutex_lock(&ext4_li_mtx);
2671         if (!ext4_li_info) {
2672                 mutex_unlock(&ext4_li_mtx);
2673                 return;
2674         }
2675
2676         mutex_lock(&ext4_li_info->li_list_mtx);
2677         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2678         mutex_unlock(&ext4_li_info->li_list_mtx);
2679         mutex_unlock(&ext4_li_mtx);
2680 }
2681
2682 static struct task_struct *ext4_lazyinit_task;
2683
2684 /*
2685  * This is the function where ext4lazyinit thread lives. It walks
2686  * through the request list searching for next scheduled filesystem.
2687  * When such a fs is found, run the lazy initialization request
2688  * (ext4_rn_li_request) and keep track of the time spend in this
2689  * function. Based on that time we compute next schedule time of
2690  * the request. When walking through the list is complete, compute
2691  * next waking time and put itself into sleep.
2692  */
2693 static int ext4_lazyinit_thread(void *arg)
2694 {
2695         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2696         struct list_head *pos, *n;
2697         struct ext4_li_request *elr;
2698         unsigned long next_wakeup, cur;
2699
2700         BUG_ON(NULL == eli);
2701
2702 cont_thread:
2703         while (true) {
2704                 next_wakeup = MAX_JIFFY_OFFSET;
2705
2706                 mutex_lock(&eli->li_list_mtx);
2707                 if (list_empty(&eli->li_request_list)) {
2708                         mutex_unlock(&eli->li_list_mtx);
2709                         goto exit_thread;
2710                 }
2711
2712                 list_for_each_safe(pos, n, &eli->li_request_list) {
2713                         elr = list_entry(pos, struct ext4_li_request,
2714                                          lr_request);
2715
2716                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2717                                 if (ext4_run_li_request(elr) != 0) {
2718                                         /* error, remove the lazy_init job */
2719                                         ext4_remove_li_request(elr);
2720                                         continue;
2721                                 }
2722                         }
2723
2724                         if (time_before(elr->lr_next_sched, next_wakeup))
2725                                 next_wakeup = elr->lr_next_sched;
2726                 }
2727                 mutex_unlock(&eli->li_list_mtx);
2728
2729                 try_to_freeze();
2730
2731                 cur = jiffies;
2732                 if ((time_after_eq(cur, next_wakeup)) ||
2733                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2734                         cond_resched();
2735                         continue;
2736                 }
2737
2738                 schedule_timeout_interruptible(next_wakeup - cur);
2739
2740                 if (kthread_should_stop()) {
2741                         ext4_clear_request_list();
2742                         goto exit_thread;
2743                 }
2744         }
2745
2746 exit_thread:
2747         /*
2748          * It looks like the request list is empty, but we need
2749          * to check it under the li_list_mtx lock, to prevent any
2750          * additions into it, and of course we should lock ext4_li_mtx
2751          * to atomically free the list and ext4_li_info, because at
2752          * this point another ext4 filesystem could be registering
2753          * new one.
2754          */
2755         mutex_lock(&ext4_li_mtx);
2756         mutex_lock(&eli->li_list_mtx);
2757         if (!list_empty(&eli->li_request_list)) {
2758                 mutex_unlock(&eli->li_list_mtx);
2759                 mutex_unlock(&ext4_li_mtx);
2760                 goto cont_thread;
2761         }
2762         mutex_unlock(&eli->li_list_mtx);
2763         kfree(ext4_li_info);
2764         ext4_li_info = NULL;
2765         mutex_unlock(&ext4_li_mtx);
2766
2767         return 0;
2768 }
2769
2770 static void ext4_clear_request_list(void)
2771 {
2772         struct list_head *pos, *n;
2773         struct ext4_li_request *elr;
2774
2775         mutex_lock(&ext4_li_info->li_list_mtx);
2776         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
2777                 elr = list_entry(pos, struct ext4_li_request,
2778                                  lr_request);
2779                 ext4_remove_li_request(elr);
2780         }
2781         mutex_unlock(&ext4_li_info->li_list_mtx);
2782 }
2783
2784 static int ext4_run_lazyinit_thread(void)
2785 {
2786         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
2787                                          ext4_li_info, "ext4lazyinit");
2788         if (IS_ERR(ext4_lazyinit_task)) {
2789                 int err = PTR_ERR(ext4_lazyinit_task);
2790                 ext4_clear_request_list();
2791                 kfree(ext4_li_info);
2792                 ext4_li_info = NULL;
2793                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
2794                                  "initialization thread\n",
2795                                  err);
2796                 return err;
2797         }
2798         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
2799         return 0;
2800 }
2801
2802 /*
2803  * Check whether it make sense to run itable init. thread or not.
2804  * If there is at least one uninitialized inode table, return
2805  * corresponding group number, else the loop goes through all
2806  * groups and return total number of groups.
2807  */
2808 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
2809 {
2810         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
2811         struct ext4_group_desc *gdp = NULL;
2812
2813         for (group = 0; group < ngroups; group++) {
2814                 gdp = ext4_get_group_desc(sb, group, NULL);
2815                 if (!gdp)
2816                         continue;
2817
2818                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2819                         break;
2820         }
2821
2822         return group;
2823 }
2824
2825 static int ext4_li_info_new(void)
2826 {
2827         struct ext4_lazy_init *eli = NULL;
2828
2829         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
2830         if (!eli)
2831                 return -ENOMEM;
2832
2833         INIT_LIST_HEAD(&eli->li_request_list);
2834         mutex_init(&eli->li_list_mtx);
2835
2836         eli->li_state |= EXT4_LAZYINIT_QUIT;
2837
2838         ext4_li_info = eli;
2839
2840         return 0;
2841 }
2842
2843 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
2844                                             ext4_group_t start)
2845 {
2846         struct ext4_sb_info *sbi = EXT4_SB(sb);
2847         struct ext4_li_request *elr;
2848         unsigned long rnd;
2849
2850         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
2851         if (!elr)
2852                 return NULL;
2853
2854         elr->lr_super = sb;
2855         elr->lr_sbi = sbi;
2856         elr->lr_next_group = start;
2857
2858         /*
2859          * Randomize first schedule time of the request to
2860          * spread the inode table initialization requests
2861          * better.
2862          */
2863         get_random_bytes(&rnd, sizeof(rnd));
2864         elr->lr_next_sched = jiffies + (unsigned long)rnd %
2865                              (EXT4_DEF_LI_MAX_START_DELAY * HZ);
2866
2867         return elr;
2868 }
2869
2870 static int ext4_register_li_request(struct super_block *sb,
2871                                     ext4_group_t first_not_zeroed)
2872 {
2873         struct ext4_sb_info *sbi = EXT4_SB(sb);
2874         struct ext4_li_request *elr;
2875         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
2876         int ret = 0;
2877
2878         if (sbi->s_li_request != NULL) {
2879                 /*
2880                  * Reset timeout so it can be computed again, because
2881                  * s_li_wait_mult might have changed.
2882                  */
2883                 sbi->s_li_request->lr_timeout = 0;
2884                 return 0;
2885         }
2886
2887         if (first_not_zeroed == ngroups ||
2888             (sb->s_flags & MS_RDONLY) ||
2889             !test_opt(sb, INIT_INODE_TABLE))
2890                 return 0;
2891
2892         elr = ext4_li_request_new(sb, first_not_zeroed);
2893         if (!elr)
2894                 return -ENOMEM;
2895
2896         mutex_lock(&ext4_li_mtx);
2897
2898         if (NULL == ext4_li_info) {
2899                 ret = ext4_li_info_new();
2900                 if (ret)
2901                         goto out;
2902         }
2903
2904         mutex_lock(&ext4_li_info->li_list_mtx);
2905         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
2906         mutex_unlock(&ext4_li_info->li_list_mtx);
2907
2908         sbi->s_li_request = elr;
2909         /*
2910          * set elr to NULL here since it has been inserted to
2911          * the request_list and the removal and free of it is
2912          * handled by ext4_clear_request_list from now on.
2913          */
2914         elr = NULL;
2915
2916         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
2917                 ret = ext4_run_lazyinit_thread();
2918                 if (ret)
2919                         goto out;
2920         }
2921 out:
2922         mutex_unlock(&ext4_li_mtx);
2923         if (ret)
2924                 kfree(elr);
2925         return ret;
2926 }
2927
2928 /*
2929  * We do not need to lock anything since this is called on
2930  * module unload.
2931  */
2932 static void ext4_destroy_lazyinit_thread(void)
2933 {
2934         /*
2935          * If thread exited earlier
2936          * there's nothing to be done.
2937          */
2938         if (!ext4_li_info || !ext4_lazyinit_task)
2939                 return;
2940
2941         kthread_stop(ext4_lazyinit_task);
2942 }
2943
2944 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
2945 {
2946         char *orig_data = kstrdup(data, GFP_KERNEL);
2947         struct buffer_head *bh;
2948         struct ext4_super_block *es = NULL;
2949         struct ext4_sb_info *sbi;
2950         ext4_fsblk_t block;
2951         ext4_fsblk_t sb_block = get_sb_block(&data);
2952         ext4_fsblk_t logical_sb_block;
2953         unsigned long offset = 0;
2954         unsigned long journal_devnum = 0;
2955         unsigned long def_mount_opts;
2956         struct inode *root;
2957         char *cp;
2958         const char *descr;
2959         int ret = -ENOMEM;
2960         int blocksize, clustersize;
2961         unsigned int db_count;
2962         unsigned int i;
2963         int needs_recovery, has_huge_files, has_bigalloc;
2964         __u64 blocks_count;
2965         int err;
2966         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
2967         ext4_group_t first_not_zeroed;
2968
2969         sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
2970         if (!sbi)
2971                 goto out_free_orig;
2972
2973         sbi->s_blockgroup_lock =
2974                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
2975         if (!sbi->s_blockgroup_lock) {
2976                 kfree(sbi);
2977                 goto out_free_orig;
2978         }
2979         sb->s_fs_info = sbi;
2980         sbi->s_mount_opt = 0;
2981         sbi->s_resuid = EXT4_DEF_RESUID;
2982         sbi->s_resgid = EXT4_DEF_RESGID;
2983         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
2984         sbi->s_sb_block = sb_block;
2985         if (sb->s_bdev->bd_part)
2986                 sbi->s_sectors_written_start =
2987                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
2988
2989         /* Cleanup superblock name */
2990         for (cp = sb->s_id; (cp = strchr(cp, '/'));)
2991                 *cp = '!';
2992
2993         ret = -EINVAL;
2994         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
2995         if (!blocksize) {
2996                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
2997                 goto out_fail;
2998         }
2999
3000         /*
3001          * The ext4 superblock will not be buffer aligned for other than 1kB
3002          * block sizes.  We need to calculate the offset from buffer start.
3003          */
3004         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3005                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3006                 offset = do_div(logical_sb_block, blocksize);
3007         } else {
3008                 logical_sb_block = sb_block;
3009         }
3010
3011         if (!(bh = sb_bread(sb, logical_sb_block))) {
3012                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3013                 goto out_fail;
3014         }
3015         /*
3016          * Note: s_es must be initialized as soon as possible because
3017          *       some ext4 macro-instructions depend on its value
3018          */
3019         es = (struct ext4_super_block *) (((char *)bh->b_data) + offset);
3020         sbi->s_es = es;
3021         sb->s_magic = le16_to_cpu(es->s_magic);
3022         if (sb->s_magic != EXT4_SUPER_MAGIC)
3023                 goto cantfind_ext4;
3024         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3025
3026         /* Set defaults before we parse the mount options */
3027         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3028         set_opt(sb, INIT_INODE_TABLE);
3029         if (def_mount_opts & EXT4_DEFM_DEBUG)
3030                 set_opt(sb, DEBUG);
3031         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3032                 set_opt(sb, GRPID);
3033         if (def_mount_opts & EXT4_DEFM_UID16)
3034                 set_opt(sb, NO_UID32);
3035         /* xattr user namespace & acls are now defaulted on */
3036 #ifdef CONFIG_EXT4_FS_XATTR
3037         set_opt(sb, XATTR_USER);
3038 #endif
3039 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3040         set_opt(sb, POSIX_ACL);
3041 #endif
3042         set_opt(sb, MBLK_IO_SUBMIT);
3043         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3044                 set_opt(sb, JOURNAL_DATA);
3045         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3046                 set_opt(sb, ORDERED_DATA);
3047         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3048                 set_opt(sb, WRITEBACK_DATA);
3049
3050         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3051                 set_opt(sb, ERRORS_PANIC);
3052         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3053                 set_opt(sb, ERRORS_CONT);
3054         else
3055                 set_opt(sb, ERRORS_RO);
3056         if (def_mount_opts & EXT4_DEFM_BLOCK_VALIDITY)
3057                 set_opt(sb, BLOCK_VALIDITY);
3058         if (def_mount_opts & EXT4_DEFM_DISCARD)
3059                 set_opt(sb, DISCARD);
3060
3061         sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
3062         sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
3063         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3064         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3065         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3066
3067         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3068                 set_opt(sb, BARRIER);
3069
3070         /*
3071          * enable delayed allocation by default
3072          * Use -o nodelalloc to turn it off
3073          */
3074         if (!IS_EXT3_SB(sb) &&
3075             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3076                 set_opt(sb, DELALLOC);
3077
3078         /*
3079          * set default s_li_wait_mult for lazyinit, for the case there is
3080          * no mount option specified.
3081          */
3082         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3083
3084         if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
3085                            &journal_devnum, &journal_ioprio, 0)) {
3086                 ext4_msg(sb, KERN_WARNING,
3087                          "failed to parse options in superblock: %s",
3088                          sbi->s_es->s_mount_opts);
3089         }
3090         sbi->s_def_mount_opt = sbi->s_mount_opt;
3091         if (!parse_options((char *) data, sb, &journal_devnum,
3092                            &journal_ioprio, 0))
3093                 goto failed_mount;
3094
3095         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3096                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3097                             "with data=journal disables delayed "
3098                             "allocation and O_DIRECT support!\n");
3099                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3100                         ext4_msg(sb, KERN_ERR, "can't mount with "
3101                                  "both data=journal and delalloc");
3102                         goto failed_mount;
3103                 }
3104                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3105                         ext4_msg(sb, KERN_ERR, "can't mount with "
3106                                  "both data=journal and delalloc");
3107                         goto failed_mount;
3108                 }
3109                 if (test_opt(sb, DELALLOC))
3110                         clear_opt(sb, DELALLOC);
3111         }
3112
3113         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3114         if (test_opt(sb, DIOREAD_NOLOCK)) {
3115                 if (blocksize < PAGE_SIZE) {
3116                         ext4_msg(sb, KERN_ERR, "can't mount with "
3117                                  "dioread_nolock if block size != PAGE_SIZE");
3118                         goto failed_mount;
3119                 }
3120         }
3121
3122         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3123                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3124
3125         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3126             (EXT4_HAS_COMPAT_FEATURE(sb, ~0U) ||
3127              EXT4_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
3128              EXT4_HAS_INCOMPAT_FEATURE(sb, ~0U)))
3129                 ext4_msg(sb, KERN_WARNING,
3130                        "feature flags set on rev 0 fs, "
3131                        "running e2fsck is recommended");
3132
3133         if (IS_EXT2_SB(sb)) {
3134                 if (ext2_feature_set_ok(sb))
3135                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3136                                  "using the ext4 subsystem");
3137                 else {
3138                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3139                                  "to feature incompatibilities");
3140                         goto failed_mount;
3141                 }
3142         }
3143
3144         if (IS_EXT3_SB(sb)) {
3145                 if (ext3_feature_set_ok(sb))
3146                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3147                                  "using the ext4 subsystem");
3148                 else {
3149                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3150                                  "to feature incompatibilities");
3151                         goto failed_mount;
3152                 }
3153         }
3154
3155         /*
3156          * Check feature flags regardless of the revision level, since we
3157          * previously didn't change the revision level when setting the flags,
3158          * so there is a chance incompat flags are set on a rev 0 filesystem.
3159          */
3160         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3161                 goto failed_mount;
3162
3163         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3164             blocksize > EXT4_MAX_BLOCK_SIZE) {
3165                 ext4_msg(sb, KERN_ERR,
3166                        "Unsupported filesystem blocksize %d", blocksize);
3167                 goto failed_mount;
3168         }
3169
3170         if (sb->s_blocksize != blocksize) {
3171                 /* Validate the filesystem blocksize */
3172                 if (!sb_set_blocksize(sb, blocksize)) {
3173                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3174                                         blocksize);
3175                         goto failed_mount;
3176                 }
3177
3178                 brelse(bh);
3179                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3180                 offset = do_div(logical_sb_block, blocksize);
3181                 bh = sb_bread(sb, logical_sb_block);
3182                 if (!bh) {
3183                         ext4_msg(sb, KERN_ERR,
3184                                "Can't read superblock on 2nd try");
3185                         goto failed_mount;
3186                 }
3187                 es = (struct ext4_super_block *)(((char *)bh->b_data) + offset);
3188                 sbi->s_es = es;
3189                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3190                         ext4_msg(sb, KERN_ERR,
3191                                "Magic mismatch, very weird!");
3192                         goto failed_mount;
3193                 }
3194         }
3195
3196         has_huge_files = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3197                                 EXT4_FEATURE_RO_COMPAT_HUGE_FILE);
3198         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3199                                                       has_huge_files);
3200         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3201
3202         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3203                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3204                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3205         } else {
3206                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3207                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3208                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3209                     (!is_power_of_2(sbi->s_inode_size)) ||
3210                     (sbi->s_inode_size > blocksize)) {
3211                         ext4_msg(sb, KERN_ERR,
3212                                "unsupported inode size: %d",
3213                                sbi->s_inode_size);
3214                         goto failed_mount;
3215                 }
3216                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3217                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3218         }
3219
3220         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3221         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_64BIT)) {
3222                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3223                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3224                     !is_power_of_2(sbi->s_desc_size)) {
3225                         ext4_msg(sb, KERN_ERR,
3226                                "unsupported descriptor size %lu",
3227                                sbi->s_desc_size);
3228                         goto failed_mount;
3229                 }
3230         } else
3231                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3232
3233         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3234         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3235         if (EXT4_INODE_SIZE(sb) == 0 || EXT4_INODES_PER_GROUP(sb) == 0)
3236                 goto cantfind_ext4;
3237
3238         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3239         if (sbi->s_inodes_per_block == 0)
3240                 goto cantfind_ext4;
3241         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3242                                         sbi->s_inodes_per_block;
3243         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3244         sbi->s_sbh = bh;
3245         sbi->s_mount_state = le16_to_cpu(es->s_state);
3246         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3247         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3248
3249         for (i = 0; i < 4; i++)
3250                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3251         sbi->s_def_hash_version = es->s_def_hash_version;
3252         i = le32_to_cpu(es->s_flags);
3253         if (i & EXT2_FLAGS_UNSIGNED_HASH)
3254                 sbi->s_hash_unsigned = 3;
3255         else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3256 #ifdef __CHAR_UNSIGNED__
3257                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3258                 sbi->s_hash_unsigned = 3;
3259 #else
3260                 es->s_flags |= cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3261 #endif
3262         }
3263
3264         /* Handle clustersize */
3265         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3266         has_bigalloc = EXT4_HAS_RO_COMPAT_FEATURE(sb,
3267                                 EXT4_FEATURE_RO_COMPAT_BIGALLOC);
3268         if (has_bigalloc) {
3269                 if (clustersize < blocksize) {
3270                         ext4_msg(sb, KERN_ERR,
3271                                  "cluster size (%d) smaller than "
3272                                  "block size (%d)", clustersize, blocksize);
3273                         goto failed_mount;
3274                 }
3275                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3276                         le32_to_cpu(es->s_log_block_size);
3277                 sbi->s_clusters_per_group =
3278                         le32_to_cpu(es->s_clusters_per_group);
3279                 if (sbi->s_clusters_per_group > blocksize * 8) {
3280                         ext4_msg(sb, KERN_ERR,
3281                                  "#clusters per group too big: %lu",
3282                                  sbi->s_clusters_per_group);
3283                         goto failed_mount;
3284                 }
3285                 if (sbi->s_blocks_per_group !=
3286                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3287                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3288                                  "clusters per group (%lu) inconsistent",
3289                                  sbi->s_blocks_per_group,
3290                                  sbi->s_clusters_per_group);
3291                         goto failed_mount;
3292                 }
3293         } else {
3294                 if (clustersize != blocksize) {
3295                         ext4_warning(sb, "fragment/cluster size (%d) != "
3296                                      "block size (%d)", clustersize,
3297                                      blocksize);
3298                         clustersize = blocksize;
3299                 }
3300                 if (sbi->s_blocks_per_group > blocksize * 8) {
3301                         ext4_msg(sb, KERN_ERR,
3302                                  "#blocks per group too big: %lu",
3303                                  sbi->s_blocks_per_group);
3304                         goto failed_mount;
3305                 }
3306                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3307                 sbi->s_cluster_bits = 0;
3308         }
3309         sbi->s_cluster_ratio = clustersize / blocksize;
3310
3311         if (sbi->s_inodes_per_group > blocksize * 8) {
3312                 ext4_msg(sb, KERN_ERR,
3313                        "#inodes per group too big: %lu",
3314                        sbi->s_inodes_per_group);
3315                 goto failed_mount;
3316         }
3317
3318         /*
3319          * Test whether we have more sectors than will fit in sector_t,
3320          * and whether the max offset is addressable by the page cache.
3321          */
3322         err = generic_check_addressable(sb->s_blocksize_bits,
3323                                         ext4_blocks_count(es));
3324         if (err) {
3325                 ext4_msg(sb, KERN_ERR, "filesystem"
3326                          " too large to mount safely on this system");
3327                 if (sizeof(sector_t) < 8)
3328                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3329                 ret = err;
3330                 goto failed_mount;
3331         }
3332
3333         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3334                 goto cantfind_ext4;
3335
3336         /* check blocks count against device size */
3337         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3338         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3339                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3340                        "exceeds size of device (%llu blocks)",
3341                        ext4_blocks_count(es), blocks_count);
3342                 goto failed_mount;
3343         }
3344
3345         /*
3346          * It makes no sense for the first data block to be beyond the end
3347          * of the filesystem.
3348          */
3349         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3350                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3351                          "block %u is beyond end of filesystem (%llu)",
3352                          le32_to_cpu(es->s_first_data_block),
3353                          ext4_blocks_count(es));
3354                 goto failed_mount;
3355         }
3356         blocks_count = (ext4_blocks_count(es) -
3357                         le32_to_cpu(es->s_first_data_block) +
3358                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3359