Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git...
[muen/linux.git] / fs / ext4 / super.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/ext4/super.c
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/fs/minix/inode.c
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  *
16  *  Big-endian to little-endian byte-swapping/bitmaps by
17  *        David S. Miller (davem@caip.rutgers.edu), 1995
18  */
19
20 #include <linux/module.h>
21 #include <linux/string.h>
22 #include <linux/fs.h>
23 #include <linux/time.h>
24 #include <linux/vmalloc.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/backing-dev.h>
29 #include <linux/parser.h>
30 #include <linux/buffer_head.h>
31 #include <linux/exportfs.h>
32 #include <linux/vfs.h>
33 #include <linux/random.h>
34 #include <linux/mount.h>
35 #include <linux/namei.h>
36 #include <linux/quotaops.h>
37 #include <linux/seq_file.h>
38 #include <linux/ctype.h>
39 #include <linux/log2.h>
40 #include <linux/crc16.h>
41 #include <linux/dax.h>
42 #include <linux/cleancache.h>
43 #include <linux/uaccess.h>
44 #include <linux/iversion.h>
45
46 #include <linux/kthread.h>
47 #include <linux/freezer.h>
48
49 #include "ext4.h"
50 #include "ext4_extents.h"       /* Needed for trace points definition */
51 #include "ext4_jbd2.h"
52 #include "xattr.h"
53 #include "acl.h"
54 #include "mballoc.h"
55 #include "fsmap.h"
56
57 #define CREATE_TRACE_POINTS
58 #include <trace/events/ext4.h>
59
60 static struct ext4_lazy_init *ext4_li_info;
61 static struct mutex ext4_li_mtx;
62 static struct ratelimit_state ext4_mount_msg_ratelimit;
63
64 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
65                              unsigned long journal_devnum);
66 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
67 static int ext4_commit_super(struct super_block *sb, int sync);
68 static void ext4_mark_recovery_complete(struct super_block *sb,
69                                         struct ext4_super_block *es);
70 static void ext4_clear_journal_err(struct super_block *sb,
71                                    struct ext4_super_block *es);
72 static int ext4_sync_fs(struct super_block *sb, int wait);
73 static int ext4_remount(struct super_block *sb, int *flags, char *data);
74 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
75 static int ext4_unfreeze(struct super_block *sb);
76 static int ext4_freeze(struct super_block *sb);
77 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
78                        const char *dev_name, void *data);
79 static inline int ext2_feature_set_ok(struct super_block *sb);
80 static inline int ext3_feature_set_ok(struct super_block *sb);
81 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
82 static void ext4_destroy_lazyinit_thread(void);
83 static void ext4_unregister_li_request(struct super_block *sb);
84 static void ext4_clear_request_list(void);
85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
86                                             unsigned int journal_inum);
87
88 /*
89  * Lock ordering
90  *
91  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
92  * i_mmap_rwsem (inode->i_mmap_rwsem)!
93  *
94  * page fault path:
95  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
96  *   page lock -> i_data_sem (rw)
97  *
98  * buffered write path:
99  * sb_start_write -> i_mutex -> mmap_sem
100  * sb_start_write -> i_mutex -> transaction start -> page lock ->
101  *   i_data_sem (rw)
102  *
103  * truncate:
104  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
106  *   i_data_sem (rw)
107  *
108  * direct IO:
109  * sb_start_write -> i_mutex -> mmap_sem
110  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
111  *
112  * writepages:
113  * transaction start -> page lock(s) -> i_data_sem (rw)
114  */
115
116 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
117 static struct file_system_type ext2_fs_type = {
118         .owner          = THIS_MODULE,
119         .name           = "ext2",
120         .mount          = ext4_mount,
121         .kill_sb        = kill_block_super,
122         .fs_flags       = FS_REQUIRES_DEV,
123 };
124 MODULE_ALIAS_FS("ext2");
125 MODULE_ALIAS("ext2");
126 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
127 #else
128 #define IS_EXT2_SB(sb) (0)
129 #endif
130
131
132 static struct file_system_type ext3_fs_type = {
133         .owner          = THIS_MODULE,
134         .name           = "ext3",
135         .mount          = ext4_mount,
136         .kill_sb        = kill_block_super,
137         .fs_flags       = FS_REQUIRES_DEV,
138 };
139 MODULE_ALIAS_FS("ext3");
140 MODULE_ALIAS("ext3");
141 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
142
143 static int ext4_verify_csum_type(struct super_block *sb,
144                                  struct ext4_super_block *es)
145 {
146         if (!ext4_has_feature_metadata_csum(sb))
147                 return 1;
148
149         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
150 }
151
152 static __le32 ext4_superblock_csum(struct super_block *sb,
153                                    struct ext4_super_block *es)
154 {
155         struct ext4_sb_info *sbi = EXT4_SB(sb);
156         int offset = offsetof(struct ext4_super_block, s_checksum);
157         __u32 csum;
158
159         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
160
161         return cpu_to_le32(csum);
162 }
163
164 static int ext4_superblock_csum_verify(struct super_block *sb,
165                                        struct ext4_super_block *es)
166 {
167         if (!ext4_has_metadata_csum(sb))
168                 return 1;
169
170         return es->s_checksum == ext4_superblock_csum(sb, es);
171 }
172
173 void ext4_superblock_csum_set(struct super_block *sb)
174 {
175         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
176
177         if (!ext4_has_metadata_csum(sb))
178                 return;
179
180         es->s_checksum = ext4_superblock_csum(sb, es);
181 }
182
183 void *ext4_kvmalloc(size_t size, gfp_t flags)
184 {
185         void *ret;
186
187         ret = kmalloc(size, flags | __GFP_NOWARN);
188         if (!ret)
189                 ret = __vmalloc(size, flags, PAGE_KERNEL);
190         return ret;
191 }
192
193 void *ext4_kvzalloc(size_t size, gfp_t flags)
194 {
195         void *ret;
196
197         ret = kzalloc(size, flags | __GFP_NOWARN);
198         if (!ret)
199                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
200         return ret;
201 }
202
203 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
204                                struct ext4_group_desc *bg)
205 {
206         return le32_to_cpu(bg->bg_block_bitmap_lo) |
207                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
208                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
209 }
210
211 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
212                                struct ext4_group_desc *bg)
213 {
214         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
215                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
216                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
217 }
218
219 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
220                               struct ext4_group_desc *bg)
221 {
222         return le32_to_cpu(bg->bg_inode_table_lo) |
223                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
224                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
225 }
226
227 __u32 ext4_free_group_clusters(struct super_block *sb,
228                                struct ext4_group_desc *bg)
229 {
230         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
231                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
232                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
233 }
234
235 __u32 ext4_free_inodes_count(struct super_block *sb,
236                               struct ext4_group_desc *bg)
237 {
238         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
239                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
240                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
241 }
242
243 __u32 ext4_used_dirs_count(struct super_block *sb,
244                               struct ext4_group_desc *bg)
245 {
246         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
247                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
248                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
249 }
250
251 __u32 ext4_itable_unused_count(struct super_block *sb,
252                               struct ext4_group_desc *bg)
253 {
254         return le16_to_cpu(bg->bg_itable_unused_lo) |
255                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
256                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
257 }
258
259 void ext4_block_bitmap_set(struct super_block *sb,
260                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
261 {
262         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
263         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
264                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
265 }
266
267 void ext4_inode_bitmap_set(struct super_block *sb,
268                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
269 {
270         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
271         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
272                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
273 }
274
275 void ext4_inode_table_set(struct super_block *sb,
276                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
277 {
278         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
279         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
280                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
281 }
282
283 void ext4_free_group_clusters_set(struct super_block *sb,
284                                   struct ext4_group_desc *bg, __u32 count)
285 {
286         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
287         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
288                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
289 }
290
291 void ext4_free_inodes_set(struct super_block *sb,
292                           struct ext4_group_desc *bg, __u32 count)
293 {
294         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
295         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
296                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
297 }
298
299 void ext4_used_dirs_set(struct super_block *sb,
300                           struct ext4_group_desc *bg, __u32 count)
301 {
302         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
303         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
304                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
305 }
306
307 void ext4_itable_unused_set(struct super_block *sb,
308                           struct ext4_group_desc *bg, __u32 count)
309 {
310         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
311         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
312                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
313 }
314
315 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
316 {
317         time64_t now = ktime_get_real_seconds();
318
319         now = clamp_val(now, 0, (1ull << 40) - 1);
320
321         *lo = cpu_to_le32(lower_32_bits(now));
322         *hi = upper_32_bits(now);
323 }
324
325 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
326 {
327         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
328 }
329 #define ext4_update_tstamp(es, tstamp) \
330         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
331 #define ext4_get_tstamp(es, tstamp) \
332         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
333
334 static void __save_error_info(struct super_block *sb, const char *func,
335                             unsigned int line)
336 {
337         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
338
339         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
340         if (bdev_read_only(sb->s_bdev))
341                 return;
342         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
343         ext4_update_tstamp(es, s_last_error_time);
344         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
345         es->s_last_error_line = cpu_to_le32(line);
346         if (!es->s_first_error_time) {
347                 es->s_first_error_time = es->s_last_error_time;
348                 es->s_first_error_time_hi = es->s_last_error_time_hi;
349                 strncpy(es->s_first_error_func, func,
350                         sizeof(es->s_first_error_func));
351                 es->s_first_error_line = cpu_to_le32(line);
352                 es->s_first_error_ino = es->s_last_error_ino;
353                 es->s_first_error_block = es->s_last_error_block;
354         }
355         /*
356          * Start the daily error reporting function if it hasn't been
357          * started already
358          */
359         if (!es->s_error_count)
360                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
361         le32_add_cpu(&es->s_error_count, 1);
362 }
363
364 static void save_error_info(struct super_block *sb, const char *func,
365                             unsigned int line)
366 {
367         __save_error_info(sb, func, line);
368         ext4_commit_super(sb, 1);
369 }
370
371 /*
372  * The del_gendisk() function uninitializes the disk-specific data
373  * structures, including the bdi structure, without telling anyone
374  * else.  Once this happens, any attempt to call mark_buffer_dirty()
375  * (for example, by ext4_commit_super), will cause a kernel OOPS.
376  * This is a kludge to prevent these oops until we can put in a proper
377  * hook in del_gendisk() to inform the VFS and file system layers.
378  */
379 static int block_device_ejected(struct super_block *sb)
380 {
381         struct inode *bd_inode = sb->s_bdev->bd_inode;
382         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
383
384         return bdi->dev == NULL;
385 }
386
387 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
388 {
389         struct super_block              *sb = journal->j_private;
390         struct ext4_sb_info             *sbi = EXT4_SB(sb);
391         int                             error = is_journal_aborted(journal);
392         struct ext4_journal_cb_entry    *jce;
393
394         BUG_ON(txn->t_state == T_FINISHED);
395
396         ext4_process_freed_data(sb, txn->t_tid);
397
398         spin_lock(&sbi->s_md_lock);
399         while (!list_empty(&txn->t_private_list)) {
400                 jce = list_entry(txn->t_private_list.next,
401                                  struct ext4_journal_cb_entry, jce_list);
402                 list_del_init(&jce->jce_list);
403                 spin_unlock(&sbi->s_md_lock);
404                 jce->jce_func(sb, jce, error);
405                 spin_lock(&sbi->s_md_lock);
406         }
407         spin_unlock(&sbi->s_md_lock);
408 }
409
410 /* Deal with the reporting of failure conditions on a filesystem such as
411  * inconsistencies detected or read IO failures.
412  *
413  * On ext2, we can store the error state of the filesystem in the
414  * superblock.  That is not possible on ext4, because we may have other
415  * write ordering constraints on the superblock which prevent us from
416  * writing it out straight away; and given that the journal is about to
417  * be aborted, we can't rely on the current, or future, transactions to
418  * write out the superblock safely.
419  *
420  * We'll just use the jbd2_journal_abort() error code to record an error in
421  * the journal instead.  On recovery, the journal will complain about
422  * that error until we've noted it down and cleared it.
423  */
424
425 static void ext4_handle_error(struct super_block *sb)
426 {
427         if (test_opt(sb, WARN_ON_ERROR))
428                 WARN_ON_ONCE(1);
429
430         if (sb_rdonly(sb))
431                 return;
432
433         if (!test_opt(sb, ERRORS_CONT)) {
434                 journal_t *journal = EXT4_SB(sb)->s_journal;
435
436                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
437                 if (journal)
438                         jbd2_journal_abort(journal, -EIO);
439         }
440         if (test_opt(sb, ERRORS_RO)) {
441                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
442                 /*
443                  * Make sure updated value of ->s_mount_flags will be visible
444                  * before ->s_flags update
445                  */
446                 smp_wmb();
447                 sb->s_flags |= SB_RDONLY;
448         }
449         if (test_opt(sb, ERRORS_PANIC)) {
450                 if (EXT4_SB(sb)->s_journal &&
451                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
452                         return;
453                 panic("EXT4-fs (device %s): panic forced after error\n",
454                         sb->s_id);
455         }
456 }
457
458 #define ext4_error_ratelimit(sb)                                        \
459                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
460                              "EXT4-fs error")
461
462 void __ext4_error(struct super_block *sb, const char *function,
463                   unsigned int line, const char *fmt, ...)
464 {
465         struct va_format vaf;
466         va_list args;
467
468         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
469                 return;
470
471         trace_ext4_error(sb, function, line);
472         if (ext4_error_ratelimit(sb)) {
473                 va_start(args, fmt);
474                 vaf.fmt = fmt;
475                 vaf.va = &args;
476                 printk(KERN_CRIT
477                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
478                        sb->s_id, function, line, current->comm, &vaf);
479                 va_end(args);
480         }
481         save_error_info(sb, function, line);
482         ext4_handle_error(sb);
483 }
484
485 void __ext4_error_inode(struct inode *inode, const char *function,
486                         unsigned int line, ext4_fsblk_t block,
487                         const char *fmt, ...)
488 {
489         va_list args;
490         struct va_format vaf;
491         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
492
493         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
494                 return;
495
496         trace_ext4_error(inode->i_sb, function, line);
497         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
498         es->s_last_error_block = cpu_to_le64(block);
499         if (ext4_error_ratelimit(inode->i_sb)) {
500                 va_start(args, fmt);
501                 vaf.fmt = fmt;
502                 vaf.va = &args;
503                 if (block)
504                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
505                                "inode #%lu: block %llu: comm %s: %pV\n",
506                                inode->i_sb->s_id, function, line, inode->i_ino,
507                                block, current->comm, &vaf);
508                 else
509                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
510                                "inode #%lu: comm %s: %pV\n",
511                                inode->i_sb->s_id, function, line, inode->i_ino,
512                                current->comm, &vaf);
513                 va_end(args);
514         }
515         save_error_info(inode->i_sb, function, line);
516         ext4_handle_error(inode->i_sb);
517 }
518
519 void __ext4_error_file(struct file *file, const char *function,
520                        unsigned int line, ext4_fsblk_t block,
521                        const char *fmt, ...)
522 {
523         va_list args;
524         struct va_format vaf;
525         struct ext4_super_block *es;
526         struct inode *inode = file_inode(file);
527         char pathname[80], *path;
528
529         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
530                 return;
531
532         trace_ext4_error(inode->i_sb, function, line);
533         es = EXT4_SB(inode->i_sb)->s_es;
534         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
535         if (ext4_error_ratelimit(inode->i_sb)) {
536                 path = file_path(file, pathname, sizeof(pathname));
537                 if (IS_ERR(path))
538                         path = "(unknown)";
539                 va_start(args, fmt);
540                 vaf.fmt = fmt;
541                 vaf.va = &args;
542                 if (block)
543                         printk(KERN_CRIT
544                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
545                                "block %llu: comm %s: path %s: %pV\n",
546                                inode->i_sb->s_id, function, line, inode->i_ino,
547                                block, current->comm, path, &vaf);
548                 else
549                         printk(KERN_CRIT
550                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
551                                "comm %s: path %s: %pV\n",
552                                inode->i_sb->s_id, function, line, inode->i_ino,
553                                current->comm, path, &vaf);
554                 va_end(args);
555         }
556         save_error_info(inode->i_sb, function, line);
557         ext4_handle_error(inode->i_sb);
558 }
559
560 const char *ext4_decode_error(struct super_block *sb, int errno,
561                               char nbuf[16])
562 {
563         char *errstr = NULL;
564
565         switch (errno) {
566         case -EFSCORRUPTED:
567                 errstr = "Corrupt filesystem";
568                 break;
569         case -EFSBADCRC:
570                 errstr = "Filesystem failed CRC";
571                 break;
572         case -EIO:
573                 errstr = "IO failure";
574                 break;
575         case -ENOMEM:
576                 errstr = "Out of memory";
577                 break;
578         case -EROFS:
579                 if (!sb || (EXT4_SB(sb)->s_journal &&
580                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
581                         errstr = "Journal has aborted";
582                 else
583                         errstr = "Readonly filesystem";
584                 break;
585         default:
586                 /* If the caller passed in an extra buffer for unknown
587                  * errors, textualise them now.  Else we just return
588                  * NULL. */
589                 if (nbuf) {
590                         /* Check for truncated error codes... */
591                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
592                                 errstr = nbuf;
593                 }
594                 break;
595         }
596
597         return errstr;
598 }
599
600 /* __ext4_std_error decodes expected errors from journaling functions
601  * automatically and invokes the appropriate error response.  */
602
603 void __ext4_std_error(struct super_block *sb, const char *function,
604                       unsigned int line, int errno)
605 {
606         char nbuf[16];
607         const char *errstr;
608
609         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
610                 return;
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 && sb_rdonly(sb))
616                 return;
617
618         if (ext4_error_ratelimit(sb)) {
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         }
623
624         save_error_info(sb, function, line);
625         ext4_handle_error(sb);
626 }
627
628 /*
629  * ext4_abort is a much stronger failure handler than ext4_error.  The
630  * abort function may be used to deal with unrecoverable failures such
631  * as journal IO errors or ENOMEM at a critical moment in log management.
632  *
633  * We unconditionally force the filesystem into an ABORT|READONLY state,
634  * unless the error response on the fs has been set to panic in which
635  * case we take the easy way out and panic immediately.
636  */
637
638 void __ext4_abort(struct super_block *sb, const char *function,
639                 unsigned int line, const char *fmt, ...)
640 {
641         struct va_format vaf;
642         va_list args;
643
644         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
645                 return;
646
647         save_error_info(sb, function, line);
648         va_start(args, fmt);
649         vaf.fmt = fmt;
650         vaf.va = &args;
651         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
652                sb->s_id, function, line, &vaf);
653         va_end(args);
654
655         if (sb_rdonly(sb) == 0) {
656                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
657                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
658                 /*
659                  * Make sure updated value of ->s_mount_flags will be visible
660                  * before ->s_flags update
661                  */
662                 smp_wmb();
663                 sb->s_flags |= SB_RDONLY;
664                 if (EXT4_SB(sb)->s_journal)
665                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
666                 save_error_info(sb, function, line);
667         }
668         if (test_opt(sb, ERRORS_PANIC)) {
669                 if (EXT4_SB(sb)->s_journal &&
670                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
671                         return;
672                 panic("EXT4-fs panic from previous error\n");
673         }
674 }
675
676 void __ext4_msg(struct super_block *sb,
677                 const char *prefix, const char *fmt, ...)
678 {
679         struct va_format vaf;
680         va_list args;
681
682         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
683                 return;
684
685         va_start(args, fmt);
686         vaf.fmt = fmt;
687         vaf.va = &args;
688         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
689         va_end(args);
690 }
691
692 #define ext4_warning_ratelimit(sb)                                      \
693                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
694                              "EXT4-fs warning")
695
696 void __ext4_warning(struct super_block *sb, const char *function,
697                     unsigned int line, const char *fmt, ...)
698 {
699         struct va_format vaf;
700         va_list args;
701
702         if (!ext4_warning_ratelimit(sb))
703                 return;
704
705         va_start(args, fmt);
706         vaf.fmt = fmt;
707         vaf.va = &args;
708         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
709                sb->s_id, function, line, &vaf);
710         va_end(args);
711 }
712
713 void __ext4_warning_inode(const struct inode *inode, const char *function,
714                           unsigned int line, const char *fmt, ...)
715 {
716         struct va_format vaf;
717         va_list args;
718
719         if (!ext4_warning_ratelimit(inode->i_sb))
720                 return;
721
722         va_start(args, fmt);
723         vaf.fmt = fmt;
724         vaf.va = &args;
725         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
726                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
727                function, line, inode->i_ino, current->comm, &vaf);
728         va_end(args);
729 }
730
731 void __ext4_grp_locked_error(const char *function, unsigned int line,
732                              struct super_block *sb, ext4_group_t grp,
733                              unsigned long ino, ext4_fsblk_t block,
734                              const char *fmt, ...)
735 __releases(bitlock)
736 __acquires(bitlock)
737 {
738         struct va_format vaf;
739         va_list args;
740         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
741
742         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
743                 return;
744
745         trace_ext4_error(sb, function, line);
746         es->s_last_error_ino = cpu_to_le32(ino);
747         es->s_last_error_block = cpu_to_le64(block);
748         __save_error_info(sb, function, line);
749
750         if (ext4_error_ratelimit(sb)) {
751                 va_start(args, fmt);
752                 vaf.fmt = fmt;
753                 vaf.va = &args;
754                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
755                        sb->s_id, function, line, grp);
756                 if (ino)
757                         printk(KERN_CONT "inode %lu: ", ino);
758                 if (block)
759                         printk(KERN_CONT "block %llu:",
760                                (unsigned long long) block);
761                 printk(KERN_CONT "%pV\n", &vaf);
762                 va_end(args);
763         }
764
765         if (test_opt(sb, WARN_ON_ERROR))
766                 WARN_ON_ONCE(1);
767
768         if (test_opt(sb, ERRORS_CONT)) {
769                 ext4_commit_super(sb, 0);
770                 return;
771         }
772
773         ext4_unlock_group(sb, grp);
774         ext4_commit_super(sb, 1);
775         ext4_handle_error(sb);
776         /*
777          * We only get here in the ERRORS_RO case; relocking the group
778          * may be dangerous, but nothing bad will happen since the
779          * filesystem will have already been marked read/only and the
780          * journal has been aborted.  We return 1 as a hint to callers
781          * who might what to use the return value from
782          * ext4_grp_locked_error() to distinguish between the
783          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
784          * aggressively from the ext4 function in question, with a
785          * more appropriate error code.
786          */
787         ext4_lock_group(sb, grp);
788         return;
789 }
790
791 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
792                                      ext4_group_t group,
793                                      unsigned int flags)
794 {
795         struct ext4_sb_info *sbi = EXT4_SB(sb);
796         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
797         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
798         int ret;
799
800         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
801                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
802                                             &grp->bb_state);
803                 if (!ret)
804                         percpu_counter_sub(&sbi->s_freeclusters_counter,
805                                            grp->bb_free);
806         }
807
808         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
809                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
810                                             &grp->bb_state);
811                 if (!ret && gdp) {
812                         int count;
813
814                         count = ext4_free_inodes_count(sb, gdp);
815                         percpu_counter_sub(&sbi->s_freeinodes_counter,
816                                            count);
817                 }
818         }
819 }
820
821 void ext4_update_dynamic_rev(struct super_block *sb)
822 {
823         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
824
825         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
826                 return;
827
828         ext4_warning(sb,
829                      "updating to rev %d because of new feature flag, "
830                      "running e2fsck is recommended",
831                      EXT4_DYNAMIC_REV);
832
833         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
834         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
835         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
836         /* leave es->s_feature_*compat flags alone */
837         /* es->s_uuid will be set by e2fsck if empty */
838
839         /*
840          * The rest of the superblock fields should be zero, and if not it
841          * means they are likely already in use, so leave them alone.  We
842          * can leave it up to e2fsck to clean up any inconsistencies there.
843          */
844 }
845
846 /*
847  * Open the external journal device
848  */
849 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
850 {
851         struct block_device *bdev;
852         char b[BDEVNAME_SIZE];
853
854         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
855         if (IS_ERR(bdev))
856                 goto fail;
857         return bdev;
858
859 fail:
860         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
861                         __bdevname(dev, b), PTR_ERR(bdev));
862         return NULL;
863 }
864
865 /*
866  * Release the journal device
867  */
868 static void ext4_blkdev_put(struct block_device *bdev)
869 {
870         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
871 }
872
873 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
874 {
875         struct block_device *bdev;
876         bdev = sbi->journal_bdev;
877         if (bdev) {
878                 ext4_blkdev_put(bdev);
879                 sbi->journal_bdev = NULL;
880         }
881 }
882
883 static inline struct inode *orphan_list_entry(struct list_head *l)
884 {
885         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
886 }
887
888 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
889 {
890         struct list_head *l;
891
892         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
893                  le32_to_cpu(sbi->s_es->s_last_orphan));
894
895         printk(KERN_ERR "sb_info orphan list:\n");
896         list_for_each(l, &sbi->s_orphan) {
897                 struct inode *inode = orphan_list_entry(l);
898                 printk(KERN_ERR "  "
899                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
900                        inode->i_sb->s_id, inode->i_ino, inode,
901                        inode->i_mode, inode->i_nlink,
902                        NEXT_ORPHAN(inode));
903         }
904 }
905
906 #ifdef CONFIG_QUOTA
907 static int ext4_quota_off(struct super_block *sb, int type);
908
909 static inline void ext4_quota_off_umount(struct super_block *sb)
910 {
911         int type;
912
913         /* Use our quota_off function to clear inode flags etc. */
914         for (type = 0; type < EXT4_MAXQUOTAS; type++)
915                 ext4_quota_off(sb, type);
916 }
917 #else
918 static inline void ext4_quota_off_umount(struct super_block *sb)
919 {
920 }
921 #endif
922
923 static void ext4_put_super(struct super_block *sb)
924 {
925         struct ext4_sb_info *sbi = EXT4_SB(sb);
926         struct ext4_super_block *es = sbi->s_es;
927         int aborted = 0;
928         int i, err;
929
930         ext4_unregister_li_request(sb);
931         ext4_quota_off_umount(sb);
932
933         destroy_workqueue(sbi->rsv_conversion_wq);
934
935         if (sbi->s_journal) {
936                 aborted = is_journal_aborted(sbi->s_journal);
937                 err = jbd2_journal_destroy(sbi->s_journal);
938                 sbi->s_journal = NULL;
939                 if ((err < 0) && !aborted)
940                         ext4_abort(sb, "Couldn't clean up the journal");
941         }
942
943         ext4_unregister_sysfs(sb);
944         ext4_es_unregister_shrinker(sbi);
945         del_timer_sync(&sbi->s_err_report);
946         ext4_release_system_zone(sb);
947         ext4_mb_release(sb);
948         ext4_ext_release(sb);
949
950         if (!sb_rdonly(sb) && !aborted) {
951                 ext4_clear_feature_journal_needs_recovery(sb);
952                 es->s_state = cpu_to_le16(sbi->s_mount_state);
953         }
954         if (!sb_rdonly(sb))
955                 ext4_commit_super(sb, 1);
956
957         for (i = 0; i < sbi->s_gdb_count; i++)
958                 brelse(sbi->s_group_desc[i]);
959         kvfree(sbi->s_group_desc);
960         kvfree(sbi->s_flex_groups);
961         percpu_counter_destroy(&sbi->s_freeclusters_counter);
962         percpu_counter_destroy(&sbi->s_freeinodes_counter);
963         percpu_counter_destroy(&sbi->s_dirs_counter);
964         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
965         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
966 #ifdef CONFIG_QUOTA
967         for (i = 0; i < EXT4_MAXQUOTAS; i++)
968                 kfree(sbi->s_qf_names[i]);
969 #endif
970
971         /* Debugging code just in case the in-memory inode orphan list
972          * isn't empty.  The on-disk one can be non-empty if we've
973          * detected an error and taken the fs readonly, but the
974          * in-memory list had better be clean by this point. */
975         if (!list_empty(&sbi->s_orphan))
976                 dump_orphan_list(sb, sbi);
977         J_ASSERT(list_empty(&sbi->s_orphan));
978
979         sync_blockdev(sb->s_bdev);
980         invalidate_bdev(sb->s_bdev);
981         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
982                 /*
983                  * Invalidate the journal device's buffers.  We don't want them
984                  * floating about in memory - the physical journal device may
985                  * hotswapped, and it breaks the `ro-after' testing code.
986                  */
987                 sync_blockdev(sbi->journal_bdev);
988                 invalidate_bdev(sbi->journal_bdev);
989                 ext4_blkdev_remove(sbi);
990         }
991         if (sbi->s_ea_inode_cache) {
992                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
993                 sbi->s_ea_inode_cache = NULL;
994         }
995         if (sbi->s_ea_block_cache) {
996                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
997                 sbi->s_ea_block_cache = NULL;
998         }
999         if (sbi->s_mmp_tsk)
1000                 kthread_stop(sbi->s_mmp_tsk);
1001         brelse(sbi->s_sbh);
1002         sb->s_fs_info = NULL;
1003         /*
1004          * Now that we are completely done shutting down the
1005          * superblock, we need to actually destroy the kobject.
1006          */
1007         kobject_put(&sbi->s_kobj);
1008         wait_for_completion(&sbi->s_kobj_unregister);
1009         if (sbi->s_chksum_driver)
1010                 crypto_free_shash(sbi->s_chksum_driver);
1011         kfree(sbi->s_blockgroup_lock);
1012         fs_put_dax(sbi->s_daxdev);
1013         kfree(sbi);
1014 }
1015
1016 static struct kmem_cache *ext4_inode_cachep;
1017
1018 /*
1019  * Called inside transaction, so use GFP_NOFS
1020  */
1021 static struct inode *ext4_alloc_inode(struct super_block *sb)
1022 {
1023         struct ext4_inode_info *ei;
1024
1025         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1026         if (!ei)
1027                 return NULL;
1028
1029         inode_set_iversion(&ei->vfs_inode, 1);
1030         spin_lock_init(&ei->i_raw_lock);
1031         INIT_LIST_HEAD(&ei->i_prealloc_list);
1032         spin_lock_init(&ei->i_prealloc_lock);
1033         ext4_es_init_tree(&ei->i_es_tree);
1034         rwlock_init(&ei->i_es_lock);
1035         INIT_LIST_HEAD(&ei->i_es_list);
1036         ei->i_es_all_nr = 0;
1037         ei->i_es_shk_nr = 0;
1038         ei->i_es_shrink_lblk = 0;
1039         ei->i_reserved_data_blocks = 0;
1040         ei->i_da_metadata_calc_len = 0;
1041         ei->i_da_metadata_calc_last_lblock = 0;
1042         spin_lock_init(&(ei->i_block_reservation_lock));
1043 #ifdef CONFIG_QUOTA
1044         ei->i_reserved_quota = 0;
1045         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1046 #endif
1047         ei->jinode = NULL;
1048         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1049         spin_lock_init(&ei->i_completed_io_lock);
1050         ei->i_sync_tid = 0;
1051         ei->i_datasync_tid = 0;
1052         atomic_set(&ei->i_unwritten, 0);
1053         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1054         return &ei->vfs_inode;
1055 }
1056
1057 static int ext4_drop_inode(struct inode *inode)
1058 {
1059         int drop = generic_drop_inode(inode);
1060
1061         trace_ext4_drop_inode(inode, drop);
1062         return drop;
1063 }
1064
1065 static void ext4_i_callback(struct rcu_head *head)
1066 {
1067         struct inode *inode = container_of(head, struct inode, i_rcu);
1068         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1069 }
1070
1071 static void ext4_destroy_inode(struct inode *inode)
1072 {
1073         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1074                 ext4_msg(inode->i_sb, KERN_ERR,
1075                          "Inode %lu (%p): orphan list check failed!",
1076                          inode->i_ino, EXT4_I(inode));
1077                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1078                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1079                                 true);
1080                 dump_stack();
1081         }
1082         call_rcu(&inode->i_rcu, ext4_i_callback);
1083 }
1084
1085 static void init_once(void *foo)
1086 {
1087         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1088
1089         INIT_LIST_HEAD(&ei->i_orphan);
1090         init_rwsem(&ei->xattr_sem);
1091         init_rwsem(&ei->i_data_sem);
1092         init_rwsem(&ei->i_mmap_sem);
1093         inode_init_once(&ei->vfs_inode);
1094 }
1095
1096 static int __init init_inodecache(void)
1097 {
1098         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1099                                 sizeof(struct ext4_inode_info), 0,
1100                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1101                                         SLAB_ACCOUNT),
1102                                 offsetof(struct ext4_inode_info, i_data),
1103                                 sizeof_field(struct ext4_inode_info, i_data),
1104                                 init_once);
1105         if (ext4_inode_cachep == NULL)
1106                 return -ENOMEM;
1107         return 0;
1108 }
1109
1110 static void destroy_inodecache(void)
1111 {
1112         /*
1113          * Make sure all delayed rcu free inodes are flushed before we
1114          * destroy cache.
1115          */
1116         rcu_barrier();
1117         kmem_cache_destroy(ext4_inode_cachep);
1118 }
1119
1120 void ext4_clear_inode(struct inode *inode)
1121 {
1122         invalidate_inode_buffers(inode);
1123         clear_inode(inode);
1124         dquot_drop(inode);
1125         ext4_discard_preallocations(inode);
1126         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1127         if (EXT4_I(inode)->jinode) {
1128                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1129                                                EXT4_I(inode)->jinode);
1130                 jbd2_free_inode(EXT4_I(inode)->jinode);
1131                 EXT4_I(inode)->jinode = NULL;
1132         }
1133         fscrypt_put_encryption_info(inode);
1134 }
1135
1136 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1137                                         u64 ino, u32 generation)
1138 {
1139         struct inode *inode;
1140
1141         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1142                 return ERR_PTR(-ESTALE);
1143         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1144                 return ERR_PTR(-ESTALE);
1145
1146         /* iget isn't really right if the inode is currently unallocated!!
1147          *
1148          * ext4_read_inode will return a bad_inode if the inode had been
1149          * deleted, so we should be safe.
1150          *
1151          * Currently we don't know the generation for parent directory, so
1152          * a generation of 0 means "accept any"
1153          */
1154         inode = ext4_iget_normal(sb, ino);
1155         if (IS_ERR(inode))
1156                 return ERR_CAST(inode);
1157         if (generation && inode->i_generation != generation) {
1158                 iput(inode);
1159                 return ERR_PTR(-ESTALE);
1160         }
1161
1162         return inode;
1163 }
1164
1165 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1166                                         int fh_len, int fh_type)
1167 {
1168         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1169                                     ext4_nfs_get_inode);
1170 }
1171
1172 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1173                                         int fh_len, int fh_type)
1174 {
1175         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1176                                     ext4_nfs_get_inode);
1177 }
1178
1179 /*
1180  * Try to release metadata pages (indirect blocks, directories) which are
1181  * mapped via the block device.  Since these pages could have journal heads
1182  * which would prevent try_to_free_buffers() from freeing them, we must use
1183  * jbd2 layer's try_to_free_buffers() function to release them.
1184  */
1185 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1186                                  gfp_t wait)
1187 {
1188         journal_t *journal = EXT4_SB(sb)->s_journal;
1189
1190         WARN_ON(PageChecked(page));
1191         if (!page_has_buffers(page))
1192                 return 0;
1193         if (journal)
1194                 return jbd2_journal_try_to_free_buffers(journal, page,
1195                                                 wait & ~__GFP_DIRECT_RECLAIM);
1196         return try_to_free_buffers(page);
1197 }
1198
1199 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1200 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1201 {
1202         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1203                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1204 }
1205
1206 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1207                                                         void *fs_data)
1208 {
1209         handle_t *handle = fs_data;
1210         int res, res2, credits, retries = 0;
1211
1212         /*
1213          * Encrypting the root directory is not allowed because e2fsck expects
1214          * lost+found to exist and be unencrypted, and encrypting the root
1215          * directory would imply encrypting the lost+found directory as well as
1216          * the filename "lost+found" itself.
1217          */
1218         if (inode->i_ino == EXT4_ROOT_INO)
1219                 return -EPERM;
1220
1221         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1222                 return -EINVAL;
1223
1224         res = ext4_convert_inline_data(inode);
1225         if (res)
1226                 return res;
1227
1228         /*
1229          * If a journal handle was specified, then the encryption context is
1230          * being set on a new inode via inheritance and is part of a larger
1231          * transaction to create the inode.  Otherwise the encryption context is
1232          * being set on an existing inode in its own transaction.  Only in the
1233          * latter case should the "retry on ENOSPC" logic be used.
1234          */
1235
1236         if (handle) {
1237                 res = ext4_xattr_set_handle(handle, inode,
1238                                             EXT4_XATTR_INDEX_ENCRYPTION,
1239                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1240                                             ctx, len, 0);
1241                 if (!res) {
1242                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1243                         ext4_clear_inode_state(inode,
1244                                         EXT4_STATE_MAY_INLINE_DATA);
1245                         /*
1246                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1247                          * S_DAX may be disabled
1248                          */
1249                         ext4_set_inode_flags(inode);
1250                 }
1251                 return res;
1252         }
1253
1254         res = dquot_initialize(inode);
1255         if (res)
1256                 return res;
1257 retry:
1258         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1259                                      &credits);
1260         if (res)
1261                 return res;
1262
1263         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1264         if (IS_ERR(handle))
1265                 return PTR_ERR(handle);
1266
1267         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1268                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1269                                     ctx, len, 0);
1270         if (!res) {
1271                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1272                 /*
1273                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1274                  * S_DAX may be disabled
1275                  */
1276                 ext4_set_inode_flags(inode);
1277                 res = ext4_mark_inode_dirty(handle, inode);
1278                 if (res)
1279                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1280         }
1281         res2 = ext4_journal_stop(handle);
1282
1283         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1284                 goto retry;
1285         if (!res)
1286                 res = res2;
1287         return res;
1288 }
1289
1290 static bool ext4_dummy_context(struct inode *inode)
1291 {
1292         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1293 }
1294
1295 static const struct fscrypt_operations ext4_cryptops = {
1296         .key_prefix             = "ext4:",
1297         .get_context            = ext4_get_context,
1298         .set_context            = ext4_set_context,
1299         .dummy_context          = ext4_dummy_context,
1300         .empty_dir              = ext4_empty_dir,
1301         .max_namelen            = EXT4_NAME_LEN,
1302 };
1303 #endif
1304
1305 #ifdef CONFIG_QUOTA
1306 static const char * const quotatypes[] = INITQFNAMES;
1307 #define QTYPE2NAME(t) (quotatypes[t])
1308
1309 static int ext4_write_dquot(struct dquot *dquot);
1310 static int ext4_acquire_dquot(struct dquot *dquot);
1311 static int ext4_release_dquot(struct dquot *dquot);
1312 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1313 static int ext4_write_info(struct super_block *sb, int type);
1314 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1315                          const struct path *path);
1316 static int ext4_quota_on_mount(struct super_block *sb, int type);
1317 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1318                                size_t len, loff_t off);
1319 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1320                                 const char *data, size_t len, loff_t off);
1321 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1322                              unsigned int flags);
1323 static int ext4_enable_quotas(struct super_block *sb);
1324 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1325
1326 static struct dquot **ext4_get_dquots(struct inode *inode)
1327 {
1328         return EXT4_I(inode)->i_dquot;
1329 }
1330
1331 static const struct dquot_operations ext4_quota_operations = {
1332         .get_reserved_space     = ext4_get_reserved_space,
1333         .write_dquot            = ext4_write_dquot,
1334         .acquire_dquot          = ext4_acquire_dquot,
1335         .release_dquot          = ext4_release_dquot,
1336         .mark_dirty             = ext4_mark_dquot_dirty,
1337         .write_info             = ext4_write_info,
1338         .alloc_dquot            = dquot_alloc,
1339         .destroy_dquot          = dquot_destroy,
1340         .get_projid             = ext4_get_projid,
1341         .get_inode_usage        = ext4_get_inode_usage,
1342         .get_next_id            = ext4_get_next_id,
1343 };
1344
1345 static const struct quotactl_ops ext4_qctl_operations = {
1346         .quota_on       = ext4_quota_on,
1347         .quota_off      = ext4_quota_off,
1348         .quota_sync     = dquot_quota_sync,
1349         .get_state      = dquot_get_state,
1350         .set_info       = dquot_set_dqinfo,
1351         .get_dqblk      = dquot_get_dqblk,
1352         .set_dqblk      = dquot_set_dqblk,
1353         .get_nextdqblk  = dquot_get_next_dqblk,
1354 };
1355 #endif
1356
1357 static const struct super_operations ext4_sops = {
1358         .alloc_inode    = ext4_alloc_inode,
1359         .destroy_inode  = ext4_destroy_inode,
1360         .write_inode    = ext4_write_inode,
1361         .dirty_inode    = ext4_dirty_inode,
1362         .drop_inode     = ext4_drop_inode,
1363         .evict_inode    = ext4_evict_inode,
1364         .put_super      = ext4_put_super,
1365         .sync_fs        = ext4_sync_fs,
1366         .freeze_fs      = ext4_freeze,
1367         .unfreeze_fs    = ext4_unfreeze,
1368         .statfs         = ext4_statfs,
1369         .remount_fs     = ext4_remount,
1370         .show_options   = ext4_show_options,
1371 #ifdef CONFIG_QUOTA
1372         .quota_read     = ext4_quota_read,
1373         .quota_write    = ext4_quota_write,
1374         .get_dquots     = ext4_get_dquots,
1375 #endif
1376         .bdev_try_to_free_page = bdev_try_to_free_page,
1377 };
1378
1379 static const struct export_operations ext4_export_ops = {
1380         .fh_to_dentry = ext4_fh_to_dentry,
1381         .fh_to_parent = ext4_fh_to_parent,
1382         .get_parent = ext4_get_parent,
1383 };
1384
1385 enum {
1386         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1387         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1388         Opt_nouid32, Opt_debug, Opt_removed,
1389         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1390         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1391         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1392         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1393         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1394         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1395         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1396         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1397         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1398         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1399         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1400         Opt_nowarn_on_error, Opt_mblk_io_submit,
1401         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1402         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1403         Opt_inode_readahead_blks, Opt_journal_ioprio,
1404         Opt_dioread_nolock, Opt_dioread_lock,
1405         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1406         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1407 };
1408
1409 static const match_table_t tokens = {
1410         {Opt_bsd_df, "bsddf"},
1411         {Opt_minix_df, "minixdf"},
1412         {Opt_grpid, "grpid"},
1413         {Opt_grpid, "bsdgroups"},
1414         {Opt_nogrpid, "nogrpid"},
1415         {Opt_nogrpid, "sysvgroups"},
1416         {Opt_resgid, "resgid=%u"},
1417         {Opt_resuid, "resuid=%u"},
1418         {Opt_sb, "sb=%u"},
1419         {Opt_err_cont, "errors=continue"},
1420         {Opt_err_panic, "errors=panic"},
1421         {Opt_err_ro, "errors=remount-ro"},
1422         {Opt_nouid32, "nouid32"},
1423         {Opt_debug, "debug"},
1424         {Opt_removed, "oldalloc"},
1425         {Opt_removed, "orlov"},
1426         {Opt_user_xattr, "user_xattr"},
1427         {Opt_nouser_xattr, "nouser_xattr"},
1428         {Opt_acl, "acl"},
1429         {Opt_noacl, "noacl"},
1430         {Opt_noload, "norecovery"},
1431         {Opt_noload, "noload"},
1432         {Opt_removed, "nobh"},
1433         {Opt_removed, "bh"},
1434         {Opt_commit, "commit=%u"},
1435         {Opt_min_batch_time, "min_batch_time=%u"},
1436         {Opt_max_batch_time, "max_batch_time=%u"},
1437         {Opt_journal_dev, "journal_dev=%u"},
1438         {Opt_journal_path, "journal_path=%s"},
1439         {Opt_journal_checksum, "journal_checksum"},
1440         {Opt_nojournal_checksum, "nojournal_checksum"},
1441         {Opt_journal_async_commit, "journal_async_commit"},
1442         {Opt_abort, "abort"},
1443         {Opt_data_journal, "data=journal"},
1444         {Opt_data_ordered, "data=ordered"},
1445         {Opt_data_writeback, "data=writeback"},
1446         {Opt_data_err_abort, "data_err=abort"},
1447         {Opt_data_err_ignore, "data_err=ignore"},
1448         {Opt_offusrjquota, "usrjquota="},
1449         {Opt_usrjquota, "usrjquota=%s"},
1450         {Opt_offgrpjquota, "grpjquota="},
1451         {Opt_grpjquota, "grpjquota=%s"},
1452         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1453         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1454         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1455         {Opt_grpquota, "grpquota"},
1456         {Opt_noquota, "noquota"},
1457         {Opt_quota, "quota"},
1458         {Opt_usrquota, "usrquota"},
1459         {Opt_prjquota, "prjquota"},
1460         {Opt_barrier, "barrier=%u"},
1461         {Opt_barrier, "barrier"},
1462         {Opt_nobarrier, "nobarrier"},
1463         {Opt_i_version, "i_version"},
1464         {Opt_dax, "dax"},
1465         {Opt_stripe, "stripe=%u"},
1466         {Opt_delalloc, "delalloc"},
1467         {Opt_warn_on_error, "warn_on_error"},
1468         {Opt_nowarn_on_error, "nowarn_on_error"},
1469         {Opt_lazytime, "lazytime"},
1470         {Opt_nolazytime, "nolazytime"},
1471         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1472         {Opt_nodelalloc, "nodelalloc"},
1473         {Opt_removed, "mblk_io_submit"},
1474         {Opt_removed, "nomblk_io_submit"},
1475         {Opt_block_validity, "block_validity"},
1476         {Opt_noblock_validity, "noblock_validity"},
1477         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1478         {Opt_journal_ioprio, "journal_ioprio=%u"},
1479         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1480         {Opt_auto_da_alloc, "auto_da_alloc"},
1481         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1482         {Opt_dioread_nolock, "dioread_nolock"},
1483         {Opt_dioread_lock, "dioread_lock"},
1484         {Opt_discard, "discard"},
1485         {Opt_nodiscard, "nodiscard"},
1486         {Opt_init_itable, "init_itable=%u"},
1487         {Opt_init_itable, "init_itable"},
1488         {Opt_noinit_itable, "noinit_itable"},
1489         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1490         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1491         {Opt_nombcache, "nombcache"},
1492         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1493         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1494         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1495         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1496         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1497         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1498         {Opt_err, NULL},
1499 };
1500
1501 static ext4_fsblk_t get_sb_block(void **data)
1502 {
1503         ext4_fsblk_t    sb_block;
1504         char            *options = (char *) *data;
1505
1506         if (!options || strncmp(options, "sb=", 3) != 0)
1507                 return 1;       /* Default location */
1508
1509         options += 3;
1510         /* TODO: use simple_strtoll with >32bit ext4 */
1511         sb_block = simple_strtoul(options, &options, 0);
1512         if (*options && *options != ',') {
1513                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1514                        (char *) *data);
1515                 return 1;
1516         }
1517         if (*options == ',')
1518                 options++;
1519         *data = (void *) options;
1520
1521         return sb_block;
1522 }
1523
1524 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1525 static const char deprecated_msg[] =
1526         "Mount option \"%s\" will be removed by %s\n"
1527         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1528
1529 #ifdef CONFIG_QUOTA
1530 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1531 {
1532         struct ext4_sb_info *sbi = EXT4_SB(sb);
1533         char *qname;
1534         int ret = -1;
1535
1536         if (sb_any_quota_loaded(sb) &&
1537                 !sbi->s_qf_names[qtype]) {
1538                 ext4_msg(sb, KERN_ERR,
1539                         "Cannot change journaled "
1540                         "quota options when quota turned on");
1541                 return -1;
1542         }
1543         if (ext4_has_feature_quota(sb)) {
1544                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1545                          "ignored when QUOTA feature is enabled");
1546                 return 1;
1547         }
1548         qname = match_strdup(args);
1549         if (!qname) {
1550                 ext4_msg(sb, KERN_ERR,
1551                         "Not enough memory for storing quotafile name");
1552                 return -1;
1553         }
1554         if (sbi->s_qf_names[qtype]) {
1555                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1556                         ret = 1;
1557                 else
1558                         ext4_msg(sb, KERN_ERR,
1559                                  "%s quota file already specified",
1560                                  QTYPE2NAME(qtype));
1561                 goto errout;
1562         }
1563         if (strchr(qname, '/')) {
1564                 ext4_msg(sb, KERN_ERR,
1565                         "quotafile must be on filesystem root");
1566                 goto errout;
1567         }
1568         sbi->s_qf_names[qtype] = qname;
1569         set_opt(sb, QUOTA);
1570         return 1;
1571 errout:
1572         kfree(qname);
1573         return ret;
1574 }
1575
1576 static int clear_qf_name(struct super_block *sb, int qtype)
1577 {
1578
1579         struct ext4_sb_info *sbi = EXT4_SB(sb);
1580
1581         if (sb_any_quota_loaded(sb) &&
1582                 sbi->s_qf_names[qtype]) {
1583                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1584                         " when quota turned on");
1585                 return -1;
1586         }
1587         kfree(sbi->s_qf_names[qtype]);
1588         sbi->s_qf_names[qtype] = NULL;
1589         return 1;
1590 }
1591 #endif
1592
1593 #define MOPT_SET        0x0001
1594 #define MOPT_CLEAR      0x0002
1595 #define MOPT_NOSUPPORT  0x0004
1596 #define MOPT_EXPLICIT   0x0008
1597 #define MOPT_CLEAR_ERR  0x0010
1598 #define MOPT_GTE0       0x0020
1599 #ifdef CONFIG_QUOTA
1600 #define MOPT_Q          0
1601 #define MOPT_QFMT       0x0040
1602 #else
1603 #define MOPT_Q          MOPT_NOSUPPORT
1604 #define MOPT_QFMT       MOPT_NOSUPPORT
1605 #endif
1606 #define MOPT_DATAJ      0x0080
1607 #define MOPT_NO_EXT2    0x0100
1608 #define MOPT_NO_EXT3    0x0200
1609 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1610 #define MOPT_STRING     0x0400
1611
1612 static const struct mount_opts {
1613         int     token;
1614         int     mount_opt;
1615         int     flags;
1616 } ext4_mount_opts[] = {
1617         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1618         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1619         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1620         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1621         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1622         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1623         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1624          MOPT_EXT4_ONLY | MOPT_SET},
1625         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1626          MOPT_EXT4_ONLY | MOPT_CLEAR},
1627         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1628         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1629         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1630          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1631         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1632          MOPT_EXT4_ONLY | MOPT_CLEAR},
1633         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1634         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1635         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1636          MOPT_EXT4_ONLY | MOPT_CLEAR},
1637         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1638          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1639         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1640                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1641          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1642         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1643         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1644         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1645         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1646         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1647          MOPT_NO_EXT2},
1648         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1649          MOPT_NO_EXT2},
1650         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1651         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1652         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1653         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1654         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1655         {Opt_commit, 0, MOPT_GTE0},
1656         {Opt_max_batch_time, 0, MOPT_GTE0},
1657         {Opt_min_batch_time, 0, MOPT_GTE0},
1658         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1659         {Opt_init_itable, 0, MOPT_GTE0},
1660         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1661         {Opt_stripe, 0, MOPT_GTE0},
1662         {Opt_resuid, 0, MOPT_GTE0},
1663         {Opt_resgid, 0, MOPT_GTE0},
1664         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1665         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1666         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1667         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1668         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1669         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1670          MOPT_NO_EXT2 | MOPT_DATAJ},
1671         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1672         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1673 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1674         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1675         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1676 #else
1677         {Opt_acl, 0, MOPT_NOSUPPORT},
1678         {Opt_noacl, 0, MOPT_NOSUPPORT},
1679 #endif
1680         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1681         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1682         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1683         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1684         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1685                                                         MOPT_SET | MOPT_Q},
1686         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1687                                                         MOPT_SET | MOPT_Q},
1688         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1689                                                         MOPT_SET | MOPT_Q},
1690         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1691                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1692                                                         MOPT_CLEAR | MOPT_Q},
1693         {Opt_usrjquota, 0, MOPT_Q},
1694         {Opt_grpjquota, 0, MOPT_Q},
1695         {Opt_offusrjquota, 0, MOPT_Q},
1696         {Opt_offgrpjquota, 0, MOPT_Q},
1697         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1698         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1699         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1700         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1701         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1702         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1703         {Opt_err, 0, 0}
1704 };
1705
1706 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1707                             substring_t *args, unsigned long *journal_devnum,
1708                             unsigned int *journal_ioprio, int is_remount)
1709 {
1710         struct ext4_sb_info *sbi = EXT4_SB(sb);
1711         const struct mount_opts *m;
1712         kuid_t uid;
1713         kgid_t gid;
1714         int arg = 0;
1715
1716 #ifdef CONFIG_QUOTA
1717         if (token == Opt_usrjquota)
1718                 return set_qf_name(sb, USRQUOTA, &args[0]);
1719         else if (token == Opt_grpjquota)
1720                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1721         else if (token == Opt_offusrjquota)
1722                 return clear_qf_name(sb, USRQUOTA);
1723         else if (token == Opt_offgrpjquota)
1724                 return clear_qf_name(sb, GRPQUOTA);
1725 #endif
1726         switch (token) {
1727         case Opt_noacl:
1728         case Opt_nouser_xattr:
1729                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1730                 break;
1731         case Opt_sb:
1732                 return 1;       /* handled by get_sb_block() */
1733         case Opt_removed:
1734                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1735                 return 1;
1736         case Opt_abort:
1737                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1738                 return 1;
1739         case Opt_i_version:
1740                 sb->s_flags |= SB_I_VERSION;
1741                 return 1;
1742         case Opt_lazytime:
1743                 sb->s_flags |= SB_LAZYTIME;
1744                 return 1;
1745         case Opt_nolazytime:
1746                 sb->s_flags &= ~SB_LAZYTIME;
1747                 return 1;
1748         }
1749
1750         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1751                 if (token == m->token)
1752                         break;
1753
1754         if (m->token == Opt_err) {
1755                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1756                          "or missing value", opt);
1757                 return -1;
1758         }
1759
1760         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1761                 ext4_msg(sb, KERN_ERR,
1762                          "Mount option \"%s\" incompatible with ext2", opt);
1763                 return -1;
1764         }
1765         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1766                 ext4_msg(sb, KERN_ERR,
1767                          "Mount option \"%s\" incompatible with ext3", opt);
1768                 return -1;
1769         }
1770
1771         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1772                 return -1;
1773         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1774                 return -1;
1775         if (m->flags & MOPT_EXPLICIT) {
1776                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1777                         set_opt2(sb, EXPLICIT_DELALLOC);
1778                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1779                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1780                 } else
1781                         return -1;
1782         }
1783         if (m->flags & MOPT_CLEAR_ERR)
1784                 clear_opt(sb, ERRORS_MASK);
1785         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1786                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1787                          "options when quota turned on");
1788                 return -1;
1789         }
1790
1791         if (m->flags & MOPT_NOSUPPORT) {
1792                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1793         } else if (token == Opt_commit) {
1794                 if (arg == 0)
1795                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1796                 sbi->s_commit_interval = HZ * arg;
1797         } else if (token == Opt_debug_want_extra_isize) {
1798                 sbi->s_want_extra_isize = arg;
1799         } else if (token == Opt_max_batch_time) {
1800                 sbi->s_max_batch_time = arg;
1801         } else if (token == Opt_min_batch_time) {
1802                 sbi->s_min_batch_time = arg;
1803         } else if (token == Opt_inode_readahead_blks) {
1804                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1805                         ext4_msg(sb, KERN_ERR,
1806                                  "EXT4-fs: inode_readahead_blks must be "
1807                                  "0 or a power of 2 smaller than 2^31");
1808                         return -1;
1809                 }
1810                 sbi->s_inode_readahead_blks = arg;
1811         } else if (token == Opt_init_itable) {
1812                 set_opt(sb, INIT_INODE_TABLE);
1813                 if (!args->from)
1814                         arg = EXT4_DEF_LI_WAIT_MULT;
1815                 sbi->s_li_wait_mult = arg;
1816         } else if (token == Opt_max_dir_size_kb) {
1817                 sbi->s_max_dir_size_kb = arg;
1818         } else if (token == Opt_stripe) {
1819                 sbi->s_stripe = arg;
1820         } else if (token == Opt_resuid) {
1821                 uid = make_kuid(current_user_ns(), arg);
1822                 if (!uid_valid(uid)) {
1823                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1824                         return -1;
1825                 }
1826                 sbi->s_resuid = uid;
1827         } else if (token == Opt_resgid) {
1828                 gid = make_kgid(current_user_ns(), arg);
1829                 if (!gid_valid(gid)) {
1830                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1831                         return -1;
1832                 }
1833                 sbi->s_resgid = gid;
1834         } else if (token == Opt_journal_dev) {
1835                 if (is_remount) {
1836                         ext4_msg(sb, KERN_ERR,
1837                                  "Cannot specify journal on remount");
1838                         return -1;
1839                 }
1840                 *journal_devnum = arg;
1841         } else if (token == Opt_journal_path) {
1842                 char *journal_path;
1843                 struct inode *journal_inode;
1844                 struct path path;
1845                 int error;
1846
1847                 if (is_remount) {
1848                         ext4_msg(sb, KERN_ERR,
1849                                  "Cannot specify journal on remount");
1850                         return -1;
1851                 }
1852                 journal_path = match_strdup(&args[0]);
1853                 if (!journal_path) {
1854                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1855                                 "journal device string");
1856                         return -1;
1857                 }
1858
1859                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1860                 if (error) {
1861                         ext4_msg(sb, KERN_ERR, "error: could not find "
1862                                 "journal device path: error %d", error);
1863                         kfree(journal_path);
1864                         return -1;
1865                 }
1866
1867                 journal_inode = d_inode(path.dentry);
1868                 if (!S_ISBLK(journal_inode->i_mode)) {
1869                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1870                                 "is not a block device", journal_path);
1871                         path_put(&path);
1872                         kfree(journal_path);
1873                         return -1;
1874                 }
1875
1876                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1877                 path_put(&path);
1878                 kfree(journal_path);
1879         } else if (token == Opt_journal_ioprio) {
1880                 if (arg > 7) {
1881                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1882                                  " (must be 0-7)");
1883                         return -1;
1884                 }
1885                 *journal_ioprio =
1886                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1887         } else if (token == Opt_test_dummy_encryption) {
1888 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1889                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1890                 ext4_msg(sb, KERN_WARNING,
1891                          "Test dummy encryption mode enabled");
1892 #else
1893                 ext4_msg(sb, KERN_WARNING,
1894                          "Test dummy encryption mount option ignored");
1895 #endif
1896         } else if (m->flags & MOPT_DATAJ) {
1897                 if (is_remount) {
1898                         if (!sbi->s_journal)
1899                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1900                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1901                                 ext4_msg(sb, KERN_ERR,
1902                                          "Cannot change data mode on remount");
1903                                 return -1;
1904                         }
1905                 } else {
1906                         clear_opt(sb, DATA_FLAGS);
1907                         sbi->s_mount_opt |= m->mount_opt;
1908                 }
1909 #ifdef CONFIG_QUOTA
1910         } else if (m->flags & MOPT_QFMT) {
1911                 if (sb_any_quota_loaded(sb) &&
1912                     sbi->s_jquota_fmt != m->mount_opt) {
1913                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1914                                  "quota options when quota turned on");
1915                         return -1;
1916                 }
1917                 if (ext4_has_feature_quota(sb)) {
1918                         ext4_msg(sb, KERN_INFO,
1919                                  "Quota format mount options ignored "
1920                                  "when QUOTA feature is enabled");
1921                         return 1;
1922                 }
1923                 sbi->s_jquota_fmt = m->mount_opt;
1924 #endif
1925         } else if (token == Opt_dax) {
1926 #ifdef CONFIG_FS_DAX
1927                 ext4_msg(sb, KERN_WARNING,
1928                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1929                         sbi->s_mount_opt |= m->mount_opt;
1930 #else
1931                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1932                 return -1;
1933 #endif
1934         } else if (token == Opt_data_err_abort) {
1935                 sbi->s_mount_opt |= m->mount_opt;
1936         } else if (token == Opt_data_err_ignore) {
1937                 sbi->s_mount_opt &= ~m->mount_opt;
1938         } else {
1939                 if (!args->from)
1940                         arg = 1;
1941                 if (m->flags & MOPT_CLEAR)
1942                         arg = !arg;
1943                 else if (unlikely(!(m->flags & MOPT_SET))) {
1944                         ext4_msg(sb, KERN_WARNING,
1945                                  "buggy handling of option %s", opt);
1946                         WARN_ON(1);
1947                         return -1;
1948                 }
1949                 if (arg != 0)
1950                         sbi->s_mount_opt |= m->mount_opt;
1951                 else
1952                         sbi->s_mount_opt &= ~m->mount_opt;
1953         }
1954         return 1;
1955 }
1956
1957 static int parse_options(char *options, struct super_block *sb,
1958                          unsigned long *journal_devnum,
1959                          unsigned int *journal_ioprio,
1960                          int is_remount)
1961 {
1962         struct ext4_sb_info *sbi = EXT4_SB(sb);
1963         char *p;
1964         substring_t args[MAX_OPT_ARGS];
1965         int token;
1966
1967         if (!options)
1968                 return 1;
1969
1970         while ((p = strsep(&options, ",")) != NULL) {
1971                 if (!*p)
1972                         continue;
1973                 /*
1974                  * Initialize args struct so we know whether arg was
1975                  * found; some options take optional arguments.
1976                  */
1977                 args[0].to = args[0].from = NULL;
1978                 token = match_token(p, tokens, args);
1979                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1980                                      journal_ioprio, is_remount) < 0)
1981                         return 0;
1982         }
1983 #ifdef CONFIG_QUOTA
1984         /*
1985          * We do the test below only for project quotas. 'usrquota' and
1986          * 'grpquota' mount options are allowed even without quota feature
1987          * to support legacy quotas in quota files.
1988          */
1989         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
1990                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
1991                          "Cannot enable project quota enforcement.");
1992                 return 0;
1993         }
1994         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1995                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1996                         clear_opt(sb, USRQUOTA);
1997
1998                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1999                         clear_opt(sb, GRPQUOTA);
2000
2001                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2002                         ext4_msg(sb, KERN_ERR, "old and new quota "
2003                                         "format mixing");
2004                         return 0;
2005                 }
2006
2007                 if (!sbi->s_jquota_fmt) {
2008                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2009                                         "not specified");
2010                         return 0;
2011                 }
2012         }
2013 #endif
2014         if (test_opt(sb, DIOREAD_NOLOCK)) {
2015                 int blocksize =
2016                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2017
2018                 if (blocksize < PAGE_SIZE) {
2019                         ext4_msg(sb, KERN_ERR, "can't mount with "
2020                                  "dioread_nolock if block size != PAGE_SIZE");
2021                         return 0;
2022                 }
2023         }
2024         return 1;
2025 }
2026
2027 static inline void ext4_show_quota_options(struct seq_file *seq,
2028                                            struct super_block *sb)
2029 {
2030 #if defined(CONFIG_QUOTA)
2031         struct ext4_sb_info *sbi = EXT4_SB(sb);
2032
2033         if (sbi->s_jquota_fmt) {
2034                 char *fmtname = "";
2035
2036                 switch (sbi->s_jquota_fmt) {
2037                 case QFMT_VFS_OLD:
2038                         fmtname = "vfsold";
2039                         break;
2040                 case QFMT_VFS_V0:
2041                         fmtname = "vfsv0";
2042                         break;
2043                 case QFMT_VFS_V1:
2044                         fmtname = "vfsv1";
2045                         break;
2046                 }
2047                 seq_printf(seq, ",jqfmt=%s", fmtname);
2048         }
2049
2050         if (sbi->s_qf_names[USRQUOTA])
2051                 seq_show_option(seq, "usrjquota", sbi->s_qf_names[USRQUOTA]);
2052
2053         if (sbi->s_qf_names[GRPQUOTA])
2054                 seq_show_option(seq, "grpjquota", sbi->s_qf_names[GRPQUOTA]);
2055 #endif
2056 }
2057
2058 static const char *token2str(int token)
2059 {
2060         const struct match_token *t;
2061
2062         for (t = tokens; t->token != Opt_err; t++)
2063                 if (t->token == token && !strchr(t->pattern, '='))
2064                         break;
2065         return t->pattern;
2066 }
2067
2068 /*
2069  * Show an option if
2070  *  - it's set to a non-default value OR
2071  *  - if the per-sb default is different from the global default
2072  */
2073 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2074                               int nodefs)
2075 {
2076         struct ext4_sb_info *sbi = EXT4_SB(sb);
2077         struct ext4_super_block *es = sbi->s_es;
2078         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2079         const struct mount_opts *m;
2080         char sep = nodefs ? '\n' : ',';
2081
2082 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2083 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2084
2085         if (sbi->s_sb_block != 1)
2086                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2087
2088         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2089                 int want_set = m->flags & MOPT_SET;
2090                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2091                     (m->flags & MOPT_CLEAR_ERR))
2092                         continue;
2093                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2094                         continue; /* skip if same as the default */
2095                 if ((want_set &&
2096                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2097                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2098                         continue; /* select Opt_noFoo vs Opt_Foo */
2099                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2100         }
2101
2102         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2103             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2104                 SEQ_OPTS_PRINT("resuid=%u",
2105                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2106         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2107             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2108                 SEQ_OPTS_PRINT("resgid=%u",
2109                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2110         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2111         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2112                 SEQ_OPTS_PUTS("errors=remount-ro");
2113         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2114                 SEQ_OPTS_PUTS("errors=continue");
2115         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2116                 SEQ_OPTS_PUTS("errors=panic");
2117         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2118                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2119         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2120                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2121         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2122                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2123         if (sb->s_flags & SB_I_VERSION)
2124                 SEQ_OPTS_PUTS("i_version");
2125         if (nodefs || sbi->s_stripe)
2126                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2127         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2128                         (sbi->s_mount_opt ^ def_mount_opt)) {
2129                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2130                         SEQ_OPTS_PUTS("data=journal");
2131                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2132                         SEQ_OPTS_PUTS("data=ordered");
2133                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2134                         SEQ_OPTS_PUTS("data=writeback");
2135         }
2136         if (nodefs ||
2137             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2138                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2139                                sbi->s_inode_readahead_blks);
2140
2141         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2142                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2143                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2144         if (nodefs || sbi->s_max_dir_size_kb)
2145                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2146         if (test_opt(sb, DATA_ERR_ABORT))
2147                 SEQ_OPTS_PUTS("data_err=abort");
2148         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2149                 SEQ_OPTS_PUTS("test_dummy_encryption");
2150
2151         ext4_show_quota_options(seq, sb);
2152         return 0;
2153 }
2154
2155 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2156 {
2157         return _ext4_show_options(seq, root->d_sb, 0);
2158 }
2159
2160 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2161 {
2162         struct super_block *sb = seq->private;
2163         int rc;
2164
2165         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2166         rc = _ext4_show_options(seq, sb, 1);
2167         seq_puts(seq, "\n");
2168         return rc;
2169 }
2170
2171 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2172                             int read_only)
2173 {
2174         struct ext4_sb_info *sbi = EXT4_SB(sb);
2175         int err = 0;
2176
2177         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2178                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2179                          "forcing read-only mode");
2180                 err = -EROFS;
2181         }
2182         if (read_only)
2183                 goto done;
2184         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2185                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2186                          "running e2fsck is recommended");
2187         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2188                 ext4_msg(sb, KERN_WARNING,
2189                          "warning: mounting fs with errors, "
2190                          "running e2fsck is recommended");
2191         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2192                  le16_to_cpu(es->s_mnt_count) >=
2193                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2194                 ext4_msg(sb, KERN_WARNING,
2195                          "warning: maximal mount count reached, "
2196                          "running e2fsck is recommended");
2197         else if (le32_to_cpu(es->s_checkinterval) &&
2198                  (ext4_get_tstamp(es, s_lastcheck) +
2199                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2200                 ext4_msg(sb, KERN_WARNING,
2201                          "warning: checktime reached, "
2202                          "running e2fsck is recommended");
2203         if (!sbi->s_journal)
2204                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2205         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2206                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2207         le16_add_cpu(&es->s_mnt_count, 1);
2208         ext4_update_tstamp(es, s_mtime);
2209         ext4_update_dynamic_rev(sb);
2210         if (sbi->s_journal)
2211                 ext4_set_feature_journal_needs_recovery(sb);
2212
2213         err = ext4_commit_super(sb, 1);
2214 done:
2215         if (test_opt(sb, DEBUG))
2216                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2217                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2218                         sb->s_blocksize,
2219                         sbi->s_groups_count,
2220                         EXT4_BLOCKS_PER_GROUP(sb),
2221                         EXT4_INODES_PER_GROUP(sb),
2222                         sbi->s_mount_opt, sbi->s_mount_opt2);
2223
2224         cleancache_init_fs(sb);
2225         return err;
2226 }
2227
2228 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2229 {
2230         struct ext4_sb_info *sbi = EXT4_SB(sb);
2231         struct flex_groups *new_groups;
2232         int size;
2233
2234         if (!sbi->s_log_groups_per_flex)
2235                 return 0;
2236
2237         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2238         if (size <= sbi->s_flex_groups_allocated)
2239                 return 0;
2240
2241         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2242         new_groups = kvzalloc(size, GFP_KERNEL);
2243         if (!new_groups) {
2244                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2245                          size / (int) sizeof(struct flex_groups));
2246                 return -ENOMEM;
2247         }
2248
2249         if (sbi->s_flex_groups) {
2250                 memcpy(new_groups, sbi->s_flex_groups,
2251                        (sbi->s_flex_groups_allocated *
2252                         sizeof(struct flex_groups)));
2253                 kvfree(sbi->s_flex_groups);
2254         }
2255         sbi->s_flex_groups = new_groups;
2256         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2257         return 0;
2258 }
2259
2260 static int ext4_fill_flex_info(struct super_block *sb)
2261 {
2262         struct ext4_sb_info *sbi = EXT4_SB(sb);
2263         struct ext4_group_desc *gdp = NULL;
2264         ext4_group_t flex_group;
2265         int i, err;
2266
2267         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2268         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2269                 sbi->s_log_groups_per_flex = 0;
2270                 return 1;
2271         }
2272
2273         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2274         if (err)
2275                 goto failed;
2276
2277         for (i = 0; i < sbi->s_groups_count; i++) {
2278                 gdp = ext4_get_group_desc(sb, i, NULL);
2279
2280                 flex_group = ext4_flex_group(sbi, i);
2281                 atomic_add(ext4_free_inodes_count(sb, gdp),
2282                            &sbi->s_flex_groups[flex_group].free_inodes);
2283                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2284                              &sbi->s_flex_groups[flex_group].free_clusters);
2285                 atomic_add(ext4_used_dirs_count(sb, gdp),
2286                            &sbi->s_flex_groups[flex_group].used_dirs);
2287         }
2288
2289         return 1;
2290 failed:
2291         return 0;
2292 }
2293
2294 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2295                                    struct ext4_group_desc *gdp)
2296 {
2297         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2298         __u16 crc = 0;
2299         __le32 le_group = cpu_to_le32(block_group);
2300         struct ext4_sb_info *sbi = EXT4_SB(sb);
2301
2302         if (ext4_has_metadata_csum(sbi->s_sb)) {
2303                 /* Use new metadata_csum algorithm */
2304                 __u32 csum32;
2305                 __u16 dummy_csum = 0;
2306
2307                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2308                                      sizeof(le_group));
2309                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2310                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2311                                      sizeof(dummy_csum));
2312                 offset += sizeof(dummy_csum);
2313                 if (offset < sbi->s_desc_size)
2314                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2315                                              sbi->s_desc_size - offset);
2316
2317                 crc = csum32 & 0xFFFF;
2318                 goto out;
2319         }
2320
2321         /* old crc16 code */
2322         if (!ext4_has_feature_gdt_csum(sb))
2323                 return 0;
2324
2325         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2326         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2327         crc = crc16(crc, (__u8 *)gdp, offset);
2328         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2329         /* for checksum of struct ext4_group_desc do the rest...*/
2330         if (ext4_has_feature_64bit(sb) &&
2331             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2332                 crc = crc16(crc, (__u8 *)gdp + offset,
2333                             le16_to_cpu(sbi->s_es->s_desc_size) -
2334                                 offset);
2335
2336 out:
2337         return cpu_to_le16(crc);
2338 }
2339
2340 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2341                                 struct ext4_group_desc *gdp)
2342 {
2343         if (ext4_has_group_desc_csum(sb) &&
2344             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2345                 return 0;
2346
2347         return 1;
2348 }
2349
2350 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2351                               struct ext4_group_desc *gdp)
2352 {
2353         if (!ext4_has_group_desc_csum(sb))
2354                 return;
2355         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2356 }
2357
2358 /* Called at mount-time, super-block is locked */
2359 static int ext4_check_descriptors(struct super_block *sb,
2360                                   ext4_fsblk_t sb_block,
2361                                   ext4_group_t *first_not_zeroed)
2362 {
2363         struct ext4_sb_info *sbi = EXT4_SB(sb);
2364         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2365         ext4_fsblk_t last_block;
2366         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2367         ext4_fsblk_t block_bitmap;
2368         ext4_fsblk_t inode_bitmap;
2369         ext4_fsblk_t inode_table;
2370         int flexbg_flag = 0;
2371         ext4_group_t i, grp = sbi->s_groups_count;
2372
2373         if (ext4_has_feature_flex_bg(sb))
2374                 flexbg_flag = 1;
2375
2376         ext4_debug("Checking group descriptors");
2377
2378         for (i = 0; i < sbi->s_groups_count; i++) {
2379                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2380
2381                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2382                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2383                 else
2384                         last_block = first_block +
2385                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2386
2387                 if ((grp == sbi->s_groups_count) &&
2388                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2389                         grp = i;
2390
2391                 block_bitmap = ext4_block_bitmap(sb, gdp);
2392                 if (block_bitmap == sb_block) {
2393                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2394                                  "Block bitmap for group %u overlaps "
2395                                  "superblock", i);
2396                         if (!sb_rdonly(sb))
2397                                 return 0;
2398                 }
2399                 if (block_bitmap >= sb_block + 1 &&
2400                     block_bitmap <= last_bg_block) {
2401                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2402                                  "Block bitmap for group %u overlaps "
2403                                  "block group descriptors", i);
2404                         if (!sb_rdonly(sb))
2405                                 return 0;
2406                 }
2407                 if (block_bitmap < first_block || block_bitmap > last_block) {
2408                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2409                                "Block bitmap for group %u not in group "
2410                                "(block %llu)!", i, block_bitmap);
2411                         return 0;
2412                 }
2413                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2414                 if (inode_bitmap == sb_block) {
2415                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2416                                  "Inode bitmap for group %u overlaps "
2417                                  "superblock", i);
2418                         if (!sb_rdonly(sb))
2419                                 return 0;
2420                 }
2421                 if (inode_bitmap >= sb_block + 1 &&
2422                     inode_bitmap <= last_bg_block) {
2423                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2424                                  "Inode bitmap for group %u overlaps "
2425                                  "block group descriptors", i);
2426                         if (!sb_rdonly(sb))
2427                                 return 0;
2428                 }
2429                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2430                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2431                                "Inode bitmap for group %u not in group "
2432                                "(block %llu)!", i, inode_bitmap);
2433                         return 0;
2434                 }
2435                 inode_table = ext4_inode_table(sb, gdp);
2436                 if (inode_table == sb_block) {
2437                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2438                                  "Inode table for group %u overlaps "
2439                                  "superblock", i);
2440                         if (!sb_rdonly(sb))
2441                                 return 0;
2442                 }
2443                 if (inode_table >= sb_block + 1 &&
2444                     inode_table <= last_bg_block) {
2445                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2446                                  "Inode table for group %u overlaps "
2447                                  "block group descriptors", i);
2448                         if (!sb_rdonly(sb))
2449                                 return 0;
2450                 }
2451                 if (inode_table < first_block ||
2452                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2453                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2454                                "Inode table for group %u not in group "
2455                                "(block %llu)!", i, inode_table);
2456                         return 0;
2457                 }
2458                 ext4_lock_group(sb, i);
2459                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2460                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2461                                  "Checksum for group %u failed (%u!=%u)",
2462                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2463                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2464                         if (!sb_rdonly(sb)) {
2465                                 ext4_unlock_group(sb, i);
2466                                 return 0;
2467                         }
2468                 }
2469                 ext4_unlock_group(sb, i);
2470                 if (!flexbg_flag)
2471                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2472         }
2473         if (NULL != first_not_zeroed)
2474                 *first_not_zeroed = grp;
2475         return 1;
2476 }
2477
2478 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2479  * the superblock) which were deleted from all directories, but held open by
2480  * a process at the time of a crash.  We walk the list and try to delete these
2481  * inodes at recovery time (only with a read-write filesystem).
2482  *
2483  * In order to keep the orphan inode chain consistent during traversal (in
2484  * case of crash during recovery), we link each inode into the superblock
2485  * orphan list_head and handle it the same way as an inode deletion during
2486  * normal operation (which journals the operations for us).
2487  *
2488  * We only do an iget() and an iput() on each inode, which is very safe if we
2489  * accidentally point at an in-use or already deleted inode.  The worst that
2490  * can happen in this case is that we get a "bit already cleared" message from
2491  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2492  * e2fsck was run on this filesystem, and it must have already done the orphan
2493  * inode cleanup for us, so we can safely abort without any further action.
2494  */
2495 static void ext4_orphan_cleanup(struct super_block *sb,
2496                                 struct ext4_super_block *es)
2497 {
2498         unsigned int s_flags = sb->s_flags;
2499         int ret, nr_orphans = 0, nr_truncates = 0;
2500 #ifdef CONFIG_QUOTA
2501         int quota_update = 0;
2502         int i;
2503 #endif
2504         if (!es->s_last_orphan) {
2505                 jbd_debug(4, "no orphan inodes to clean up\n");
2506                 return;
2507         }
2508
2509         if (bdev_read_only(sb->s_bdev)) {
2510                 ext4_msg(sb, KERN_ERR, "write access "
2511                         "unavailable, skipping orphan cleanup");
2512                 return;
2513         }
2514
2515         /* Check if feature set would not allow a r/w mount */
2516         if (!ext4_feature_set_ok(sb, 0)) {
2517                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2518                          "unknown ROCOMPAT features");
2519                 return;
2520         }
2521
2522         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2523                 /* don't clear list on RO mount w/ errors */
2524                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2525                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2526                                   "clearing orphan list.\n");
2527                         es->s_last_orphan = 0;
2528                 }
2529                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2530                 return;
2531         }
2532
2533         if (s_flags & SB_RDONLY) {
2534                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2535                 sb->s_flags &= ~SB_RDONLY;
2536         }
2537 #ifdef CONFIG_QUOTA
2538         /* Needed for iput() to work correctly and not trash data */
2539         sb->s_flags |= SB_ACTIVE;
2540
2541         /*
2542          * Turn on quotas which were not enabled for read-only mounts if
2543          * filesystem has quota feature, so that they are updated correctly.
2544          */
2545         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2546                 int ret = ext4_enable_quotas(sb);
2547
2548                 if (!ret)
2549                         quota_update = 1;
2550                 else
2551                         ext4_msg(sb, KERN_ERR,
2552                                 "Cannot turn on quotas: error %d", ret);
2553         }
2554
2555         /* Turn on journaled quotas used for old sytle */
2556         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2557                 if (EXT4_SB(sb)->s_qf_names[i]) {
2558                         int ret = ext4_quota_on_mount(sb, i);
2559
2560                         if (!ret)
2561                                 quota_update = 1;
2562                         else
2563                                 ext4_msg(sb, KERN_ERR,
2564                                         "Cannot turn on journaled "
2565                                         "quota: type %d: error %d", i, ret);
2566                 }
2567         }
2568 #endif
2569
2570         while (es->s_last_orphan) {
2571                 struct inode *inode;
2572
2573                 /*
2574                  * We may have encountered an error during cleanup; if
2575                  * so, skip the rest.
2576                  */
2577                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2578                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2579                         es->s_last_orphan = 0;
2580                         break;
2581                 }
2582
2583                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2584                 if (IS_ERR(inode)) {
2585                         es->s_last_orphan = 0;
2586                         break;
2587                 }
2588
2589                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2590                 dquot_initialize(inode);
2591                 if (inode->i_nlink) {
2592                         if (test_opt(sb, DEBUG))
2593                                 ext4_msg(sb, KERN_DEBUG,
2594                                         "%s: truncating inode %lu to %lld bytes",
2595                                         __func__, inode->i_ino, inode->i_size);
2596                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2597                                   inode->i_ino, inode->i_size);
2598                         inode_lock(inode);
2599                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2600                         ret = ext4_truncate(inode);
2601                         if (ret)
2602                                 ext4_std_error(inode->i_sb, ret);
2603                         inode_unlock(inode);
2604                         nr_truncates++;
2605                 } else {
2606                         if (test_opt(sb, DEBUG))
2607                                 ext4_msg(sb, KERN_DEBUG,
2608                                         "%s: deleting unreferenced inode %lu",
2609                                         __func__, inode->i_ino);
2610                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2611                                   inode->i_ino);
2612                         nr_orphans++;
2613                 }
2614                 iput(inode);  /* The delete magic happens here! */
2615         }
2616
2617 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2618
2619         if (nr_orphans)
2620                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2621                        PLURAL(nr_orphans));
2622         if (nr_truncates)
2623                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2624                        PLURAL(nr_truncates));
2625 #ifdef CONFIG_QUOTA
2626         /* Turn off quotas if they were enabled for orphan cleanup */
2627         if (quota_update) {
2628                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2629                         if (sb_dqopt(sb)->files[i])
2630                                 dquot_quota_off(sb, i);
2631                 }
2632         }
2633 #endif
2634         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2635 }
2636
2637 /*
2638  * Maximal extent format file size.
2639  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2640  * extent format containers, within a sector_t, and within i_blocks
2641  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2642  * so that won't be a limiting factor.
2643  *
2644  * However there is other limiting factor. We do store extents in the form
2645  * of starting block and length, hence the resulting length of the extent
2646  * covering maximum file size must fit into on-disk format containers as
2647  * well. Given that length is always by 1 unit bigger than max unit (because
2648  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2649  *
2650  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2651  */
2652 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2653 {
2654         loff_t res;
2655         loff_t upper_limit = MAX_LFS_FILESIZE;
2656
2657         /* small i_blocks in vfs inode? */
2658         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2659                 /*
2660                  * CONFIG_LBDAF is not enabled implies the inode
2661                  * i_block represent total blocks in 512 bytes
2662                  * 32 == size of vfs inode i_blocks * 8
2663                  */
2664                 upper_limit = (1LL << 32) - 1;
2665
2666                 /* total blocks in file system block size */
2667                 upper_limit >>= (blkbits - 9);
2668                 upper_limit <<= blkbits;
2669         }
2670
2671         /*
2672          * 32-bit extent-start container, ee_block. We lower the maxbytes
2673          * by one fs block, so ee_len can cover the extent of maximum file
2674          * size
2675          */
2676         res = (1LL << 32) - 1;
2677         res <<= blkbits;
2678
2679         /* Sanity check against vm- & vfs- imposed limits */
2680         if (res > upper_limit)
2681                 res = upper_limit;
2682
2683         return res;
2684 }
2685
2686 /*
2687  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2688  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2689  * We need to be 1 filesystem block less than the 2^48 sector limit.
2690  */
2691 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2692 {
2693         loff_t res = EXT4_NDIR_BLOCKS;
2694         int meta_blocks;
2695         loff_t upper_limit;
2696         /* This is calculated to be the largest file size for a dense, block
2697          * mapped file such that the file's total number of 512-byte sectors,
2698          * including data and all indirect blocks, does not exceed (2^48 - 1).
2699          *
2700          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2701          * number of 512-byte sectors of the file.
2702          */
2703
2704         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2705                 /*
2706                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2707                  * the inode i_block field represents total file blocks in
2708                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2709                  */
2710                 upper_limit = (1LL << 32) - 1;
2711
2712                 /* total blocks in file system block size */
2713                 upper_limit >>= (bits - 9);
2714
2715         } else {
2716                 /*
2717                  * We use 48 bit ext4_inode i_blocks
2718                  * With EXT4_HUGE_FILE_FL set the i_blocks
2719                  * represent total number of blocks in
2720                  * file system block size
2721                  */
2722                 upper_limit = (1LL << 48) - 1;
2723
2724         }
2725
2726         /* indirect blocks */
2727         meta_blocks = 1;
2728         /* double indirect blocks */
2729         meta_blocks += 1 + (1LL << (bits-2));
2730         /* tripple indirect blocks */
2731         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2732
2733         upper_limit -= meta_blocks;
2734         upper_limit <<= bits;
2735
2736         res += 1LL << (bits-2);
2737         res += 1LL << (2*(bits-2));
2738         res += 1LL << (3*(bits-2));
2739         res <<= bits;
2740         if (res > upper_limit)
2741                 res = upper_limit;
2742
2743         if (res > MAX_LFS_FILESIZE)
2744                 res = MAX_LFS_FILESIZE;
2745
2746         return res;
2747 }
2748
2749 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2750                                    ext4_fsblk_t logical_sb_block, int nr)
2751 {
2752         struct ext4_sb_info *sbi = EXT4_SB(sb);
2753         ext4_group_t bg, first_meta_bg;
2754         int has_super = 0;
2755
2756         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2757
2758         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2759                 return logical_sb_block + nr + 1;
2760         bg = sbi->s_desc_per_block * nr;
2761         if (ext4_bg_has_super(sb, bg))
2762                 has_super = 1;
2763
2764         /*
2765          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2766          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2767          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2768          * compensate.
2769          */
2770         if (sb->s_blocksize == 1024 && nr == 0 &&
2771             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2772                 has_super++;
2773
2774         return (has_super + ext4_group_first_block_no(sb, bg));
2775 }
2776
2777 /**
2778  * ext4_get_stripe_size: Get the stripe size.
2779  * @sbi: In memory super block info
2780  *
2781  * If we have specified it via mount option, then
2782  * use the mount option value. If the value specified at mount time is
2783  * greater than the blocks per group use the super block value.
2784  * If the super block value is greater than blocks per group return 0.
2785  * Allocator needs it be less than blocks per group.
2786  *
2787  */
2788 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2789 {
2790         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2791         unsigned long stripe_width =
2792                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2793         int ret;
2794
2795         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2796                 ret = sbi->s_stripe;
2797         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2798                 ret = stripe_width;
2799         else if (stride && stride <= sbi->s_blocks_per_group)
2800                 ret = stride;
2801         else
2802                 ret = 0;
2803
2804         /*
2805          * If the stripe width is 1, this makes no sense and
2806          * we set it to 0 to turn off stripe handling code.
2807          */
2808         if (ret <= 1)
2809                 ret = 0;
2810
2811         return ret;
2812 }
2813
2814 /*
2815  * Check whether this filesystem can be mounted based on
2816  * the features present and the RDONLY/RDWR mount requested.
2817  * Returns 1 if this filesystem can be mounted as requested,
2818  * 0 if it cannot be.
2819  */
2820 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2821 {
2822         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2823                 ext4_msg(sb, KERN_ERR,
2824                         "Couldn't mount because of "
2825                         "unsupported optional features (%x)",
2826                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2827                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2828                 return 0;
2829         }
2830
2831         if (readonly)
2832                 return 1;
2833
2834         if (ext4_has_feature_readonly(sb)) {
2835                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2836                 sb->s_flags |= SB_RDONLY;
2837                 return 1;
2838         }
2839
2840         /* Check that feature set is OK for a read-write mount */
2841         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2842                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2843                          "unsupported optional features (%x)",
2844                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2845                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2846                 return 0;
2847         }
2848         /*
2849          * Large file size enabled file system can only be mounted
2850          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2851          */
2852         if (ext4_has_feature_huge_file(sb)) {
2853                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2854                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2855                                  "cannot be mounted RDWR without "
2856                                  "CONFIG_LBDAF");
2857                         return 0;
2858                 }
2859         }
2860         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2861                 ext4_msg(sb, KERN_ERR,
2862                          "Can't support bigalloc feature without "
2863                          "extents feature\n");
2864                 return 0;
2865         }
2866
2867 #ifndef CONFIG_QUOTA
2868         if (ext4_has_feature_quota(sb) && !readonly) {
2869                 ext4_msg(sb, KERN_ERR,
2870                          "Filesystem with quota feature cannot be mounted RDWR "
2871                          "without CONFIG_QUOTA");
2872                 return 0;
2873         }
2874         if (ext4_has_feature_project(sb) && !readonly) {
2875                 ext4_msg(sb, KERN_ERR,
2876                          "Filesystem with project quota feature cannot be mounted RDWR "
2877                          "without CONFIG_QUOTA");
2878                 return 0;
2879         }
2880 #endif  /* CONFIG_QUOTA */
2881         return 1;
2882 }
2883
2884 /*
2885  * This function is called once a day if we have errors logged
2886  * on the file system
2887  */
2888 static void print_daily_error_info(struct timer_list *t)
2889 {
2890         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2891         struct super_block *sb = sbi->s_sb;
2892         struct ext4_super_block *es = sbi->s_es;
2893
2894         if (es->s_error_count)
2895                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2896                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2897                          le32_to_cpu(es->s_error_count));
2898         if (es->s_first_error_time) {
2899                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
2900                        sb->s_id,
2901                        ext4_get_tstamp(es, s_first_error_time),
2902                        (int) sizeof(es->s_first_error_func),
2903                        es->s_first_error_func,
2904                        le32_to_cpu(es->s_first_error_line));
2905                 if (es->s_first_error_ino)
2906                         printk(KERN_CONT ": inode %u",
2907                                le32_to_cpu(es->s_first_error_ino));
2908                 if (es->s_first_error_block)
2909                         printk(KERN_CONT ": block %llu", (unsigned long long)
2910                                le64_to_cpu(es->s_first_error_block));
2911                 printk(KERN_CONT "\n");
2912         }
2913         if (es->s_last_error_time) {
2914                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
2915                        sb->s_id,
2916                        ext4_get_tstamp(es, s_last_error_time),
2917                        (int) sizeof(es->s_last_error_func),
2918                        es->s_last_error_func,
2919                        le32_to_cpu(es->s_last_error_line));
2920                 if (es->s_last_error_ino)
2921                         printk(KERN_CONT ": inode %u",
2922                                le32_to_cpu(es->s_last_error_ino));
2923                 if (es->s_last_error_block)
2924                         printk(KERN_CONT ": block %llu", (unsigned long long)
2925                                le64_to_cpu(es->s_last_error_block));
2926                 printk(KERN_CONT "\n");
2927         }
2928         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2929 }
2930
2931 /* Find next suitable group and run ext4_init_inode_table */
2932 static int ext4_run_li_request(struct ext4_li_request *elr)
2933 {
2934         struct ext4_group_desc *gdp = NULL;
2935         ext4_group_t group, ngroups;
2936         struct super_block *sb;
2937         unsigned long timeout = 0;
2938         int ret = 0;
2939
2940         sb = elr->lr_super;
2941         ngroups = EXT4_SB(sb)->s_groups_count;
2942
2943         for (group = elr->lr_next_group; group < ngroups; group++) {
2944                 gdp = ext4_get_group_desc(sb, group, NULL);
2945                 if (!gdp) {
2946                         ret = 1;
2947                         break;
2948                 }
2949
2950                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2951                         break;
2952         }
2953
2954         if (group >= ngroups)
2955                 ret = 1;
2956
2957         if (!ret) {
2958                 timeout = jiffies;
2959                 ret = ext4_init_inode_table(sb, group,
2960                                             elr->lr_timeout ? 0 : 1);
2961                 if (elr->lr_timeout == 0) {
2962                         timeout = (jiffies - timeout) *
2963                                   elr->lr_sbi->s_li_wait_mult;
2964                         elr->lr_timeout = timeout;
2965                 }
2966                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2967                 elr->lr_next_group = group + 1;
2968         }
2969         return ret;
2970 }
2971
2972 /*
2973  * Remove lr_request from the list_request and free the
2974  * request structure. Should be called with li_list_mtx held
2975  */
2976 static void ext4_remove_li_request(struct ext4_li_request *elr)
2977 {
2978         struct ext4_sb_info *sbi;
2979
2980         if (!elr)
2981                 return;
2982
2983         sbi = elr->lr_sbi;
2984
2985         list_del(&elr->lr_request);
2986         sbi->s_li_request = NULL;
2987         kfree(elr);
2988 }
2989
2990 static void ext4_unregister_li_request(struct super_block *sb)
2991 {
2992         mutex_lock(&ext4_li_mtx);
2993         if (!ext4_li_info) {
2994                 mutex_unlock(&ext4_li_mtx);
2995                 return;
2996         }
2997
2998         mutex_lock(&ext4_li_info->li_list_mtx);
2999         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3000         mutex_unlock(&ext4_li_info->li_list_mtx);
3001         mutex_unlock(&ext4_li_mtx);
3002 }
3003
3004 static struct task_struct *ext4_lazyinit_task;
3005
3006 /*
3007  * This is the function where ext4lazyinit thread lives. It walks
3008  * through the request list searching for next scheduled filesystem.
3009  * When such a fs is found, run the lazy initialization request
3010  * (ext4_rn_li_request) and keep track of the time spend in this
3011  * function. Based on that time we compute next schedule time of
3012  * the request. When walking through the list is complete, compute
3013  * next waking time and put itself into sleep.
3014  */
3015 static int ext4_lazyinit_thread(void *arg)
3016 {
3017         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3018         struct list_head *pos, *n;
3019         struct ext4_li_request *elr;
3020         unsigned long next_wakeup, cur;
3021
3022         BUG_ON(NULL == eli);
3023
3024 cont_thread:
3025         while (true) {
3026                 next_wakeup = MAX_JIFFY_OFFSET;
3027
3028                 mutex_lock(&eli->li_list_mtx);
3029                 if (list_empty(&eli->li_request_list)) {
3030                         mutex_unlock(&eli->li_list_mtx);
3031                         goto exit_thread;
3032                 }
3033                 list_for_each_safe(pos, n, &eli->li_request_list) {
3034                         int err = 0;
3035                         int progress = 0;
3036                         elr = list_entry(pos, struct ext4_li_request,
3037                                          lr_request);
3038
3039                         if (time_before(jiffies, elr->lr_next_sched)) {
3040                                 if (time_before(elr->lr_next_sched, next_wakeup))
3041                                         next_wakeup = elr->lr_next_sched;
3042                                 continue;
3043                         }
3044                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3045                                 if (sb_start_write_trylock(elr->lr_super)) {
3046                                         progress = 1;
3047                                         /*
3048                                          * We hold sb->s_umount, sb can not
3049                                          * be removed from the list, it is
3050                                          * now safe to drop li_list_mtx
3051                                          */
3052                                         mutex_unlock(&eli->li_list_mtx);
3053                                         err = ext4_run_li_request(elr);
3054                                         sb_end_write(elr->lr_super);
3055                                         mutex_lock(&eli->li_list_mtx);
3056                                         n = pos->next;
3057                                 }
3058                                 up_read((&elr->lr_super->s_umount));
3059                         }
3060                         /* error, remove the lazy_init job */
3061                         if (err) {
3062                                 ext4_remove_li_request(elr);
3063                                 continue;
3064                         }
3065                         if (!progress) {
3066                                 elr->lr_next_sched = jiffies +
3067                                         (prandom_u32()
3068                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3069                         }
3070                         if (time_before(elr->lr_next_sched, next_wakeup))
3071                                 next_wakeup = elr->lr_next_sched;
3072                 }
3073                 mutex_unlock(&eli->li_list_mtx);
3074
3075                 try_to_freeze();
3076
3077                 cur = jiffies;
3078                 if ((time_after_eq(cur, next_wakeup)) ||
3079                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3080                         cond_resched();
3081                         continue;
3082                 }
3083
3084                 schedule_timeout_interruptible(next_wakeup - cur);
3085
3086                 if (kthread_should_stop()) {
3087                         ext4_clear_request_list();
3088                         goto exit_thread;
3089                 }
3090         }
3091
3092 exit_thread:
3093         /*
3094          * It looks like the request list is empty, but we need
3095          * to check it under the li_list_mtx lock, to prevent any
3096          * additions into it, and of course we should lock ext4_li_mtx
3097          * to atomically free the list and ext4_li_info, because at
3098          * this point another ext4 filesystem could be registering
3099          * new one.
3100          */
3101         mutex_lock(&ext4_li_mtx);
3102         mutex_lock(&eli->li_list_mtx);
3103         if (!list_empty(&eli->li_request_list)) {
3104                 mutex_unlock(&eli->li_list_mtx);
3105                 mutex_unlock(&ext4_li_mtx);
3106                 goto cont_thread;
3107         }
3108         mutex_unlock(&eli->li_list_mtx);
3109         kfree(ext4_li_info);
3110         ext4_li_info = NULL;
3111         mutex_unlock(&ext4_li_mtx);
3112
3113         return 0;
3114 }
3115
3116 static void ext4_clear_request_list(void)
3117 {
3118         struct list_head *pos, *n;
3119         struct ext4_li_request *elr;
3120
3121         mutex_lock(&ext4_li_info->li_list_mtx);
3122         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3123                 elr = list_entry(pos, struct ext4_li_request,
3124                                  lr_request);
3125                 ext4_remove_li_request(elr);
3126         }
3127         mutex_unlock(&ext4_li_info->li_list_mtx);
3128 }
3129
3130 static int ext4_run_lazyinit_thread(void)
3131 {
3132         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3133                                          ext4_li_info, "ext4lazyinit");
3134         if (IS_ERR(ext4_lazyinit_task)) {
3135                 int err = PTR_ERR(ext4_lazyinit_task);
3136                 ext4_clear_request_list();
3137                 kfree(ext4_li_info);
3138                 ext4_li_info = NULL;
3139                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3140                                  "initialization thread\n",
3141                                  err);
3142                 return err;
3143         }
3144         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3145         return 0;
3146 }
3147
3148 /*
3149  * Check whether it make sense to run itable init. thread or not.
3150  * If there is at least one uninitialized inode table, return
3151  * corresponding group number, else the loop goes through all
3152  * groups and return total number of groups.
3153  */
3154 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3155 {
3156         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3157         struct ext4_group_desc *gdp = NULL;
3158
3159         if (!ext4_has_group_desc_csum(sb))
3160                 return ngroups;
3161
3162         for (group = 0; group < ngroups; group++) {
3163                 gdp = ext4_get_group_desc(sb, group, NULL);
3164                 if (!gdp)
3165                         continue;
3166
3167                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3168                         break;
3169         }
3170
3171         return group;
3172 }
3173
3174 static int ext4_li_info_new(void)
3175 {
3176         struct ext4_lazy_init *eli = NULL;
3177
3178         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3179         if (!eli)
3180                 return -ENOMEM;
3181
3182         INIT_LIST_HEAD(&eli->li_request_list);
3183         mutex_init(&eli->li_list_mtx);
3184
3185         eli->li_state |= EXT4_LAZYINIT_QUIT;
3186
3187         ext4_li_info = eli;
3188
3189         return 0;
3190 }
3191
3192 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3193                                             ext4_group_t start)
3194 {
3195         struct ext4_sb_info *sbi = EXT4_SB(sb);
3196         struct ext4_li_request *elr;
3197
3198         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3199         if (!elr)
3200                 return NULL;
3201
3202         elr->lr_super = sb;
3203         elr->lr_sbi = sbi;
3204         elr->lr_next_group = start;
3205
3206         /*
3207          * Randomize first schedule time of the request to
3208          * spread the inode table initialization requests
3209          * better.
3210          */
3211         elr->lr_next_sched = jiffies + (prandom_u32() %
3212                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3213         return elr;
3214 }
3215
3216 int ext4_register_li_request(struct super_block *sb,
3217                              ext4_group_t first_not_zeroed)
3218 {
3219         struct ext4_sb_info *sbi = EXT4_SB(sb);
3220         struct ext4_li_request *elr = NULL;
3221         ext4_group_t ngroups = sbi->s_groups_count;
3222         int ret = 0;
3223
3224         mutex_lock(&ext4_li_mtx);
3225         if (sbi->s_li_request != NULL) {
3226                 /*
3227                  * Reset timeout so it can be computed again, because
3228                  * s_li_wait_mult might have changed.
3229                  */
3230                 sbi->s_li_request->lr_timeout = 0;
3231                 goto out;
3232         }
3233
3234         if (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3235             !test_opt(sb, INIT_INODE_TABLE))
3236                 goto out;
3237
3238         elr = ext4_li_request_new(sb, first_not_zeroed);
3239         if (!elr) {
3240                 ret = -ENOMEM;
3241                 goto out;
3242         }
3243
3244         if (NULL == ext4_li_info) {
3245                 ret = ext4_li_info_new();
3246                 if (ret)
3247                         goto out;
3248         }
3249
3250         mutex_lock(&ext4_li_info->li_list_mtx);
3251         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3252         mutex_unlock(&ext4_li_info->li_list_mtx);
3253
3254         sbi->s_li_request = elr;
3255         /*
3256          * set elr to NULL here since it has been inserted to
3257          * the request_list and the removal and free of it is
3258          * handled by ext4_clear_request_list from now on.
3259          */
3260         elr = NULL;
3261
3262         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3263                 ret = ext4_run_lazyinit_thread();
3264                 if (ret)
3265                         goto out;
3266         }
3267 out:
3268         mutex_unlock(&ext4_li_mtx);
3269         if (ret)
3270                 kfree(elr);
3271         return ret;
3272 }
3273
3274 /*
3275  * We do not need to lock anything since this is called on
3276  * module unload.
3277  */
3278 static void ext4_destroy_lazyinit_thread(void)
3279 {
3280         /*
3281          * If thread exited earlier
3282          * there's nothing to be done.
3283          */
3284         if (!ext4_li_info || !ext4_lazyinit_task)
3285                 return;
3286
3287         kthread_stop(ext4_lazyinit_task);
3288 }
3289
3290 static int set_journal_csum_feature_set(struct super_block *sb)
3291 {
3292         int ret = 1;
3293         int compat, incompat;
3294         struct ext4_sb_info *sbi = EXT4_SB(sb);
3295
3296         if (ext4_has_metadata_csum(sb)) {
3297                 /* journal checksum v3 */
3298                 compat = 0;
3299                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3300         } else {
3301                 /* journal checksum v1 */
3302                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3303                 incompat = 0;
3304         }
3305
3306         jbd2_journal_clear_features(sbi->s_journal,
3307                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3308                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3309                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3310         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3311                 ret = jbd2_journal_set_features(sbi->s_journal,
3312                                 compat, 0,
3313                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3314                                 incompat);
3315         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3316                 ret = jbd2_journal_set_features(sbi->s_journal,
3317                                 compat, 0,
3318                                 incompat);
3319                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3320                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3321         } else {
3322                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3323                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3324         }
3325
3326         return ret;
3327 }
3328
3329 /*
3330  * Note: calculating the overhead so we can be compatible with
3331  * historical BSD practice is quite difficult in the face of
3332  * clusters/bigalloc.  This is because multiple metadata blocks from
3333  * different block group can end up in the same allocation cluster.
3334  * Calculating the exact overhead in the face of clustered allocation
3335  * requires either O(all block bitmaps) in memory or O(number of block
3336  * groups**2) in time.  We will still calculate the superblock for
3337  * older file systems --- and if we come across with a bigalloc file
3338  * system with zero in s_overhead_clusters the estimate will be close to
3339  * correct especially for very large cluster sizes --- but for newer
3340  * file systems, it's better to calculate this figure once at mkfs
3341  * time, and store it in the superblock.  If the superblock value is
3342  * present (even for non-bigalloc file systems), we will use it.
3343  */
3344 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3345                           char *buf)
3346 {
3347         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3348         struct ext4_group_desc  *gdp;
3349         ext4_fsblk_t            first_block, last_block, b;
3350         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3351         int                     s, j, count = 0;
3352
3353         if (!ext4_has_feature_bigalloc(sb))
3354                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3355                         sbi->s_itb_per_group + 2);
3356
3357         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3358                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3359         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3360         for (i = 0; i < ngroups; i++) {
3361                 gdp = ext4_get_group_desc(sb, i, NULL);
3362                 b = ext4_block_bitmap(sb, gdp);
3363                 if (b >= first_block && b <= last_block) {
3364                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3365                         count++;
3366                 }
3367                 b = ext4_inode_bitmap(sb, gdp);
3368                 if (b >= first_block && b <= last_block) {
3369                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3370                         count++;
3371                 }
3372                 b = ext4_inode_table(sb, gdp);
3373                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3374                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3375                                 int c = EXT4_B2C(sbi, b - first_block);
3376                                 ext4_set_bit(c, buf);
3377                                 count++;
3378                         }
3379                 if (i != grp)
3380                         continue;
3381                 s = 0;