Merge tag 'amd-drm-fixes-5.11-2020-12-23' of git://people.freedesktop.org/~agd5f...
[linux-2.6-microblaze.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 #include <linux/unicode.h>
46 #include <linux/part_stat.h>
47 #include <linux/kthread.h>
48 #include <linux/freezer.h>
49
50 #include "ext4.h"
51 #include "ext4_extents.h"       /* Needed for trace points definition */
52 #include "ext4_jbd2.h"
53 #include "xattr.h"
54 #include "acl.h"
55 #include "mballoc.h"
56 #include "fsmap.h"
57
58 #define CREATE_TRACE_POINTS
59 #include <trace/events/ext4.h>
60
61 static struct ext4_lazy_init *ext4_li_info;
62 static struct mutex ext4_li_mtx;
63 static struct ratelimit_state ext4_mount_msg_ratelimit;
64
65 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
66                              unsigned long journal_devnum);
67 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
68 static int ext4_commit_super(struct super_block *sb, int sync);
69 static int ext4_mark_recovery_complete(struct super_block *sb,
70                                         struct ext4_super_block *es);
71 static int ext4_clear_journal_err(struct super_block *sb,
72                                   struct ext4_super_block *es);
73 static int ext4_sync_fs(struct super_block *sb, int wait);
74 static int ext4_remount(struct super_block *sb, int *flags, char *data);
75 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
76 static int ext4_unfreeze(struct super_block *sb);
77 static int ext4_freeze(struct super_block *sb);
78 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
79                        const char *dev_name, void *data);
80 static inline int ext2_feature_set_ok(struct super_block *sb);
81 static inline int ext3_feature_set_ok(struct super_block *sb);
82 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
83 static void ext4_destroy_lazyinit_thread(void);
84 static void ext4_unregister_li_request(struct super_block *sb);
85 static void ext4_clear_request_list(void);
86 static struct inode *ext4_get_journal_inode(struct super_block *sb,
87                                             unsigned int journal_inum);
88
89 /*
90  * Lock ordering
91  *
92  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
93  * i_mmap_rwsem (inode->i_mmap_rwsem)!
94  *
95  * page fault path:
96  * mmap_lock -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
97  *   page lock -> i_data_sem (rw)
98  *
99  * buffered write path:
100  * sb_start_write -> i_mutex -> mmap_lock
101  * sb_start_write -> i_mutex -> transaction start -> page lock ->
102  *   i_data_sem (rw)
103  *
104  * truncate:
105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
106  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
107  *   i_data_sem (rw)
108  *
109  * direct IO:
110  * sb_start_write -> i_mutex -> mmap_lock
111  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
112  *
113  * writepages:
114  * transaction start -> page lock(s) -> i_data_sem (rw)
115  */
116
117 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
118 static struct file_system_type ext2_fs_type = {
119         .owner          = THIS_MODULE,
120         .name           = "ext2",
121         .mount          = ext4_mount,
122         .kill_sb        = kill_block_super,
123         .fs_flags       = FS_REQUIRES_DEV,
124 };
125 MODULE_ALIAS_FS("ext2");
126 MODULE_ALIAS("ext2");
127 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
128 #else
129 #define IS_EXT2_SB(sb) (0)
130 #endif
131
132
133 static struct file_system_type ext3_fs_type = {
134         .owner          = THIS_MODULE,
135         .name           = "ext3",
136         .mount          = ext4_mount,
137         .kill_sb        = kill_block_super,
138         .fs_flags       = FS_REQUIRES_DEV,
139 };
140 MODULE_ALIAS_FS("ext3");
141 MODULE_ALIAS("ext3");
142 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
143
144
145 static inline void __ext4_read_bh(struct buffer_head *bh, int op_flags,
146                                   bh_end_io_t *end_io)
147 {
148         /*
149          * buffer's verified bit is no longer valid after reading from
150          * disk again due to write out error, clear it to make sure we
151          * recheck the buffer contents.
152          */
153         clear_buffer_verified(bh);
154
155         bh->b_end_io = end_io ? end_io : end_buffer_read_sync;
156         get_bh(bh);
157         submit_bh(REQ_OP_READ, op_flags, bh);
158 }
159
160 void ext4_read_bh_nowait(struct buffer_head *bh, int op_flags,
161                          bh_end_io_t *end_io)
162 {
163         BUG_ON(!buffer_locked(bh));
164
165         if (ext4_buffer_uptodate(bh)) {
166                 unlock_buffer(bh);
167                 return;
168         }
169         __ext4_read_bh(bh, op_flags, end_io);
170 }
171
172 int ext4_read_bh(struct buffer_head *bh, int op_flags, bh_end_io_t *end_io)
173 {
174         BUG_ON(!buffer_locked(bh));
175
176         if (ext4_buffer_uptodate(bh)) {
177                 unlock_buffer(bh);
178                 return 0;
179         }
180
181         __ext4_read_bh(bh, op_flags, end_io);
182
183         wait_on_buffer(bh);
184         if (buffer_uptodate(bh))
185                 return 0;
186         return -EIO;
187 }
188
189 int ext4_read_bh_lock(struct buffer_head *bh, int op_flags, bool wait)
190 {
191         if (trylock_buffer(bh)) {
192                 if (wait)
193                         return ext4_read_bh(bh, op_flags, NULL);
194                 ext4_read_bh_nowait(bh, op_flags, NULL);
195                 return 0;
196         }
197         if (wait) {
198                 wait_on_buffer(bh);
199                 if (buffer_uptodate(bh))
200                         return 0;
201                 return -EIO;
202         }
203         return 0;
204 }
205
206 /*
207  * This works like __bread_gfp() except it uses ERR_PTR for error
208  * returns.  Currently with sb_bread it's impossible to distinguish
209  * between ENOMEM and EIO situations (since both result in a NULL
210  * return.
211  */
212 static struct buffer_head *__ext4_sb_bread_gfp(struct super_block *sb,
213                                                sector_t block, int op_flags,
214                                                gfp_t gfp)
215 {
216         struct buffer_head *bh;
217         int ret;
218
219         bh = sb_getblk_gfp(sb, block, gfp);
220         if (bh == NULL)
221                 return ERR_PTR(-ENOMEM);
222         if (ext4_buffer_uptodate(bh))
223                 return bh;
224
225         ret = ext4_read_bh_lock(bh, REQ_META | op_flags, true);
226         if (ret) {
227                 put_bh(bh);
228                 return ERR_PTR(ret);
229         }
230         return bh;
231 }
232
233 struct buffer_head *ext4_sb_bread(struct super_block *sb, sector_t block,
234                                    int op_flags)
235 {
236         return __ext4_sb_bread_gfp(sb, block, op_flags, __GFP_MOVABLE);
237 }
238
239 struct buffer_head *ext4_sb_bread_unmovable(struct super_block *sb,
240                                             sector_t block)
241 {
242         return __ext4_sb_bread_gfp(sb, block, 0, 0);
243 }
244
245 void ext4_sb_breadahead_unmovable(struct super_block *sb, sector_t block)
246 {
247         struct buffer_head *bh = sb_getblk_gfp(sb, block, 0);
248
249         if (likely(bh)) {
250                 ext4_read_bh_lock(bh, REQ_RAHEAD, false);
251                 brelse(bh);
252         }
253 }
254
255 static int ext4_verify_csum_type(struct super_block *sb,
256                                  struct ext4_super_block *es)
257 {
258         if (!ext4_has_feature_metadata_csum(sb))
259                 return 1;
260
261         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
262 }
263
264 static __le32 ext4_superblock_csum(struct super_block *sb,
265                                    struct ext4_super_block *es)
266 {
267         struct ext4_sb_info *sbi = EXT4_SB(sb);
268         int offset = offsetof(struct ext4_super_block, s_checksum);
269         __u32 csum;
270
271         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
272
273         return cpu_to_le32(csum);
274 }
275
276 static int ext4_superblock_csum_verify(struct super_block *sb,
277                                        struct ext4_super_block *es)
278 {
279         if (!ext4_has_metadata_csum(sb))
280                 return 1;
281
282         return es->s_checksum == ext4_superblock_csum(sb, es);
283 }
284
285 void ext4_superblock_csum_set(struct super_block *sb)
286 {
287         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
288
289         if (!ext4_has_metadata_csum(sb))
290                 return;
291
292         es->s_checksum = ext4_superblock_csum(sb, es);
293 }
294
295 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
296                                struct ext4_group_desc *bg)
297 {
298         return le32_to_cpu(bg->bg_block_bitmap_lo) |
299                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
300                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
301 }
302
303 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
304                                struct ext4_group_desc *bg)
305 {
306         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
307                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
308                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
309 }
310
311 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
312                               struct ext4_group_desc *bg)
313 {
314         return le32_to_cpu(bg->bg_inode_table_lo) |
315                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
316                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
317 }
318
319 __u32 ext4_free_group_clusters(struct super_block *sb,
320                                struct ext4_group_desc *bg)
321 {
322         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
323                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
324                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
325 }
326
327 __u32 ext4_free_inodes_count(struct super_block *sb,
328                               struct ext4_group_desc *bg)
329 {
330         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
331                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
332                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
333 }
334
335 __u32 ext4_used_dirs_count(struct super_block *sb,
336                               struct ext4_group_desc *bg)
337 {
338         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
339                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
340                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
341 }
342
343 __u32 ext4_itable_unused_count(struct super_block *sb,
344                               struct ext4_group_desc *bg)
345 {
346         return le16_to_cpu(bg->bg_itable_unused_lo) |
347                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
348                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
349 }
350
351 void ext4_block_bitmap_set(struct super_block *sb,
352                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
353 {
354         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
355         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
356                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
357 }
358
359 void ext4_inode_bitmap_set(struct super_block *sb,
360                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
361 {
362         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
363         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
364                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
365 }
366
367 void ext4_inode_table_set(struct super_block *sb,
368                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
369 {
370         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
371         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
372                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
373 }
374
375 void ext4_free_group_clusters_set(struct super_block *sb,
376                                   struct ext4_group_desc *bg, __u32 count)
377 {
378         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
379         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
380                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
381 }
382
383 void ext4_free_inodes_set(struct super_block *sb,
384                           struct ext4_group_desc *bg, __u32 count)
385 {
386         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
387         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
388                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
389 }
390
391 void ext4_used_dirs_set(struct super_block *sb,
392                           struct ext4_group_desc *bg, __u32 count)
393 {
394         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
395         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
396                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
397 }
398
399 void ext4_itable_unused_set(struct super_block *sb,
400                           struct ext4_group_desc *bg, __u32 count)
401 {
402         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
403         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
404                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
405 }
406
407 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
408 {
409         time64_t now = ktime_get_real_seconds();
410
411         now = clamp_val(now, 0, (1ull << 40) - 1);
412
413         *lo = cpu_to_le32(lower_32_bits(now));
414         *hi = upper_32_bits(now);
415 }
416
417 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
418 {
419         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
420 }
421 #define ext4_update_tstamp(es, tstamp) \
422         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
423 #define ext4_get_tstamp(es, tstamp) \
424         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
425
426 static void __save_error_info(struct super_block *sb, int error,
427                               __u32 ino, __u64 block,
428                               const char *func, unsigned int line)
429 {
430         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
431         int err;
432
433         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
434         if (bdev_read_only(sb->s_bdev))
435                 return;
436         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
437         ext4_update_tstamp(es, s_last_error_time);
438         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
439         es->s_last_error_line = cpu_to_le32(line);
440         es->s_last_error_ino = cpu_to_le32(ino);
441         es->s_last_error_block = cpu_to_le64(block);
442         switch (error) {
443         case EIO:
444                 err = EXT4_ERR_EIO;
445                 break;
446         case ENOMEM:
447                 err = EXT4_ERR_ENOMEM;
448                 break;
449         case EFSBADCRC:
450                 err = EXT4_ERR_EFSBADCRC;
451                 break;
452         case 0:
453         case EFSCORRUPTED:
454                 err = EXT4_ERR_EFSCORRUPTED;
455                 break;
456         case ENOSPC:
457                 err = EXT4_ERR_ENOSPC;
458                 break;
459         case ENOKEY:
460                 err = EXT4_ERR_ENOKEY;
461                 break;
462         case EROFS:
463                 err = EXT4_ERR_EROFS;
464                 break;
465         case EFBIG:
466                 err = EXT4_ERR_EFBIG;
467                 break;
468         case EEXIST:
469                 err = EXT4_ERR_EEXIST;
470                 break;
471         case ERANGE:
472                 err = EXT4_ERR_ERANGE;
473                 break;
474         case EOVERFLOW:
475                 err = EXT4_ERR_EOVERFLOW;
476                 break;
477         case EBUSY:
478                 err = EXT4_ERR_EBUSY;
479                 break;
480         case ENOTDIR:
481                 err = EXT4_ERR_ENOTDIR;
482                 break;
483         case ENOTEMPTY:
484                 err = EXT4_ERR_ENOTEMPTY;
485                 break;
486         case ESHUTDOWN:
487                 err = EXT4_ERR_ESHUTDOWN;
488                 break;
489         case EFAULT:
490                 err = EXT4_ERR_EFAULT;
491                 break;
492         default:
493                 err = EXT4_ERR_UNKNOWN;
494         }
495         es->s_last_error_errcode = err;
496         if (!es->s_first_error_time) {
497                 es->s_first_error_time = es->s_last_error_time;
498                 es->s_first_error_time_hi = es->s_last_error_time_hi;
499                 strncpy(es->s_first_error_func, func,
500                         sizeof(es->s_first_error_func));
501                 es->s_first_error_line = cpu_to_le32(line);
502                 es->s_first_error_ino = es->s_last_error_ino;
503                 es->s_first_error_block = es->s_last_error_block;
504                 es->s_first_error_errcode = es->s_last_error_errcode;
505         }
506         /*
507          * Start the daily error reporting function if it hasn't been
508          * started already
509          */
510         if (!es->s_error_count)
511                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
512         le32_add_cpu(&es->s_error_count, 1);
513 }
514
515 static void save_error_info(struct super_block *sb, int error,
516                             __u32 ino, __u64 block,
517                             const char *func, unsigned int line)
518 {
519         __save_error_info(sb, error, ino, block, func, line);
520         if (!bdev_read_only(sb->s_bdev))
521                 ext4_commit_super(sb, 1);
522 }
523
524 /*
525  * The del_gendisk() function uninitializes the disk-specific data
526  * structures, including the bdi structure, without telling anyone
527  * else.  Once this happens, any attempt to call mark_buffer_dirty()
528  * (for example, by ext4_commit_super), will cause a kernel OOPS.
529  * This is a kludge to prevent these oops until we can put in a proper
530  * hook in del_gendisk() to inform the VFS and file system layers.
531  */
532 static int block_device_ejected(struct super_block *sb)
533 {
534         struct inode *bd_inode = sb->s_bdev->bd_inode;
535         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
536
537         return bdi->dev == NULL;
538 }
539
540 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
541 {
542         struct super_block              *sb = journal->j_private;
543         struct ext4_sb_info             *sbi = EXT4_SB(sb);
544         int                             error = is_journal_aborted(journal);
545         struct ext4_journal_cb_entry    *jce;
546
547         BUG_ON(txn->t_state == T_FINISHED);
548
549         ext4_process_freed_data(sb, txn->t_tid);
550
551         spin_lock(&sbi->s_md_lock);
552         while (!list_empty(&txn->t_private_list)) {
553                 jce = list_entry(txn->t_private_list.next,
554                                  struct ext4_journal_cb_entry, jce_list);
555                 list_del_init(&jce->jce_list);
556                 spin_unlock(&sbi->s_md_lock);
557                 jce->jce_func(sb, jce, error);
558                 spin_lock(&sbi->s_md_lock);
559         }
560         spin_unlock(&sbi->s_md_lock);
561 }
562
563 /*
564  * This writepage callback for write_cache_pages()
565  * takes care of a few cases after page cleaning.
566  *
567  * write_cache_pages() already checks for dirty pages
568  * and calls clear_page_dirty_for_io(), which we want,
569  * to write protect the pages.
570  *
571  * However, we may have to redirty a page (see below.)
572  */
573 static int ext4_journalled_writepage_callback(struct page *page,
574                                               struct writeback_control *wbc,
575                                               void *data)
576 {
577         transaction_t *transaction = (transaction_t *) data;
578         struct buffer_head *bh, *head;
579         struct journal_head *jh;
580
581         bh = head = page_buffers(page);
582         do {
583                 /*
584                  * We have to redirty a page in these cases:
585                  * 1) If buffer is dirty, it means the page was dirty because it
586                  * contains a buffer that needs checkpointing. So the dirty bit
587                  * needs to be preserved so that checkpointing writes the buffer
588                  * properly.
589                  * 2) If buffer is not part of the committing transaction
590                  * (we may have just accidentally come across this buffer because
591                  * inode range tracking is not exact) or if the currently running
592                  * transaction already contains this buffer as well, dirty bit
593                  * needs to be preserved so that the buffer gets writeprotected
594                  * properly on running transaction's commit.
595                  */
596                 jh = bh2jh(bh);
597                 if (buffer_dirty(bh) ||
598                     (jh && (jh->b_transaction != transaction ||
599                             jh->b_next_transaction))) {
600                         redirty_page_for_writepage(wbc, page);
601                         goto out;
602                 }
603         } while ((bh = bh->b_this_page) != head);
604
605 out:
606         return AOP_WRITEPAGE_ACTIVATE;
607 }
608
609 static int ext4_journalled_submit_inode_data_buffers(struct jbd2_inode *jinode)
610 {
611         struct address_space *mapping = jinode->i_vfs_inode->i_mapping;
612         struct writeback_control wbc = {
613                 .sync_mode =  WB_SYNC_ALL,
614                 .nr_to_write = LONG_MAX,
615                 .range_start = jinode->i_dirty_start,
616                 .range_end = jinode->i_dirty_end,
617         };
618
619         return write_cache_pages(mapping, &wbc,
620                                  ext4_journalled_writepage_callback,
621                                  jinode->i_transaction);
622 }
623
624 static int ext4_journal_submit_inode_data_buffers(struct jbd2_inode *jinode)
625 {
626         int ret;
627
628         if (ext4_should_journal_data(jinode->i_vfs_inode))
629                 ret = ext4_journalled_submit_inode_data_buffers(jinode);
630         else
631                 ret = jbd2_journal_submit_inode_data_buffers(jinode);
632
633         return ret;
634 }
635
636 static int ext4_journal_finish_inode_data_buffers(struct jbd2_inode *jinode)
637 {
638         int ret = 0;
639
640         if (!ext4_should_journal_data(jinode->i_vfs_inode))
641                 ret = jbd2_journal_finish_inode_data_buffers(jinode);
642
643         return ret;
644 }
645
646 static bool system_going_down(void)
647 {
648         return system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF
649                 || system_state == SYSTEM_RESTART;
650 }
651
652 /* Deal with the reporting of failure conditions on a filesystem such as
653  * inconsistencies detected or read IO failures.
654  *
655  * On ext2, we can store the error state of the filesystem in the
656  * superblock.  That is not possible on ext4, because we may have other
657  * write ordering constraints on the superblock which prevent us from
658  * writing it out straight away; and given that the journal is about to
659  * be aborted, we can't rely on the current, or future, transactions to
660  * write out the superblock safely.
661  *
662  * We'll just use the jbd2_journal_abort() error code to record an error in
663  * the journal instead.  On recovery, the journal will complain about
664  * that error until we've noted it down and cleared it.
665  */
666
667 static void ext4_handle_error(struct super_block *sb)
668 {
669         if (test_opt(sb, WARN_ON_ERROR))
670                 WARN_ON_ONCE(1);
671
672         if (sb_rdonly(sb))
673                 return;
674
675         if (!test_opt(sb, ERRORS_CONT)) {
676                 journal_t *journal = EXT4_SB(sb)->s_journal;
677
678                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
679                 if (journal)
680                         jbd2_journal_abort(journal, -EIO);
681         }
682         /*
683          * We force ERRORS_RO behavior when system is rebooting. Otherwise we
684          * could panic during 'reboot -f' as the underlying device got already
685          * disabled.
686          */
687         if (test_opt(sb, ERRORS_RO) || system_going_down()) {
688                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
689                 /*
690                  * Make sure updated value of ->s_mount_flags will be visible
691                  * before ->s_flags update
692                  */
693                 smp_wmb();
694                 sb->s_flags |= SB_RDONLY;
695         } else if (test_opt(sb, ERRORS_PANIC)) {
696                 panic("EXT4-fs (device %s): panic forced after error\n",
697                         sb->s_id);
698         }
699 }
700
701 #define ext4_error_ratelimit(sb)                                        \
702                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
703                              "EXT4-fs error")
704
705 void __ext4_error(struct super_block *sb, const char *function,
706                   unsigned int line, int error, __u64 block,
707                   const char *fmt, ...)
708 {
709         struct va_format vaf;
710         va_list args;
711
712         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
713                 return;
714
715         trace_ext4_error(sb, function, line);
716         if (ext4_error_ratelimit(sb)) {
717                 va_start(args, fmt);
718                 vaf.fmt = fmt;
719                 vaf.va = &args;
720                 printk(KERN_CRIT
721                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
722                        sb->s_id, function, line, current->comm, &vaf);
723                 va_end(args);
724         }
725         save_error_info(sb, error, 0, block, function, line);
726         ext4_handle_error(sb);
727 }
728
729 void __ext4_error_inode(struct inode *inode, const char *function,
730                         unsigned int line, ext4_fsblk_t block, int error,
731                         const char *fmt, ...)
732 {
733         va_list args;
734         struct va_format vaf;
735
736         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
737                 return;
738
739         trace_ext4_error(inode->i_sb, function, line);
740         if (ext4_error_ratelimit(inode->i_sb)) {
741                 va_start(args, fmt);
742                 vaf.fmt = fmt;
743                 vaf.va = &args;
744                 if (block)
745                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
746                                "inode #%lu: block %llu: comm %s: %pV\n",
747                                inode->i_sb->s_id, function, line, inode->i_ino,
748                                block, current->comm, &vaf);
749                 else
750                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
751                                "inode #%lu: comm %s: %pV\n",
752                                inode->i_sb->s_id, function, line, inode->i_ino,
753                                current->comm, &vaf);
754                 va_end(args);
755         }
756         save_error_info(inode->i_sb, error, inode->i_ino, block,
757                         function, line);
758         ext4_handle_error(inode->i_sb);
759 }
760
761 void __ext4_error_file(struct file *file, const char *function,
762                        unsigned int line, ext4_fsblk_t block,
763                        const char *fmt, ...)
764 {
765         va_list args;
766         struct va_format vaf;
767         struct inode *inode = file_inode(file);
768         char pathname[80], *path;
769
770         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
771                 return;
772
773         trace_ext4_error(inode->i_sb, function, line);
774         if (ext4_error_ratelimit(inode->i_sb)) {
775                 path = file_path(file, pathname, sizeof(pathname));
776                 if (IS_ERR(path))
777                         path = "(unknown)";
778                 va_start(args, fmt);
779                 vaf.fmt = fmt;
780                 vaf.va = &args;
781                 if (block)
782                         printk(KERN_CRIT
783                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
784                                "block %llu: comm %s: path %s: %pV\n",
785                                inode->i_sb->s_id, function, line, inode->i_ino,
786                                block, current->comm, path, &vaf);
787                 else
788                         printk(KERN_CRIT
789                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
790                                "comm %s: path %s: %pV\n",
791                                inode->i_sb->s_id, function, line, inode->i_ino,
792                                current->comm, path, &vaf);
793                 va_end(args);
794         }
795         save_error_info(inode->i_sb, EFSCORRUPTED, inode->i_ino, block,
796                         function, line);
797         ext4_handle_error(inode->i_sb);
798 }
799
800 const char *ext4_decode_error(struct super_block *sb, int errno,
801                               char nbuf[16])
802 {
803         char *errstr = NULL;
804
805         switch (errno) {
806         case -EFSCORRUPTED:
807                 errstr = "Corrupt filesystem";
808                 break;
809         case -EFSBADCRC:
810                 errstr = "Filesystem failed CRC";
811                 break;
812         case -EIO:
813                 errstr = "IO failure";
814                 break;
815         case -ENOMEM:
816                 errstr = "Out of memory";
817                 break;
818         case -EROFS:
819                 if (!sb || (EXT4_SB(sb)->s_journal &&
820                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
821                         errstr = "Journal has aborted";
822                 else
823                         errstr = "Readonly filesystem";
824                 break;
825         default:
826                 /* If the caller passed in an extra buffer for unknown
827                  * errors, textualise them now.  Else we just return
828                  * NULL. */
829                 if (nbuf) {
830                         /* Check for truncated error codes... */
831                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
832                                 errstr = nbuf;
833                 }
834                 break;
835         }
836
837         return errstr;
838 }
839
840 /* __ext4_std_error decodes expected errors from journaling functions
841  * automatically and invokes the appropriate error response.  */
842
843 void __ext4_std_error(struct super_block *sb, const char *function,
844                       unsigned int line, int errno)
845 {
846         char nbuf[16];
847         const char *errstr;
848
849         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
850                 return;
851
852         /* Special case: if the error is EROFS, and we're not already
853          * inside a transaction, then there's really no point in logging
854          * an error. */
855         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
856                 return;
857
858         if (ext4_error_ratelimit(sb)) {
859                 errstr = ext4_decode_error(sb, errno, nbuf);
860                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
861                        sb->s_id, function, line, errstr);
862         }
863
864         save_error_info(sb, -errno, 0, 0, function, line);
865         ext4_handle_error(sb);
866 }
867
868 /*
869  * ext4_abort is a much stronger failure handler than ext4_error.  The
870  * abort function may be used to deal with unrecoverable failures such
871  * as journal IO errors or ENOMEM at a critical moment in log management.
872  *
873  * We unconditionally force the filesystem into an ABORT|READONLY state,
874  * unless the error response on the fs has been set to panic in which
875  * case we take the easy way out and panic immediately.
876  */
877
878 void __ext4_abort(struct super_block *sb, const char *function,
879                   unsigned int line, int error, const char *fmt, ...)
880 {
881         struct va_format vaf;
882         va_list args;
883
884         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
885                 return;
886
887         save_error_info(sb, error, 0, 0, function, line);
888         va_start(args, fmt);
889         vaf.fmt = fmt;
890         vaf.va = &args;
891         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
892                sb->s_id, function, line, &vaf);
893         va_end(args);
894
895         if (sb_rdonly(sb) == 0) {
896                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
897                 if (EXT4_SB(sb)->s_journal)
898                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
899
900                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
901                 /*
902                  * Make sure updated value of ->s_mount_flags will be visible
903                  * before ->s_flags update
904                  */
905                 smp_wmb();
906                 sb->s_flags |= SB_RDONLY;
907         }
908         if (test_opt(sb, ERRORS_PANIC) && !system_going_down())
909                 panic("EXT4-fs panic from previous error\n");
910 }
911
912 void __ext4_msg(struct super_block *sb,
913                 const char *prefix, const char *fmt, ...)
914 {
915         struct va_format vaf;
916         va_list args;
917
918         atomic_inc(&EXT4_SB(sb)->s_msg_count);
919         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
920                 return;
921
922         va_start(args, fmt);
923         vaf.fmt = fmt;
924         vaf.va = &args;
925         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
926         va_end(args);
927 }
928
929 static int ext4_warning_ratelimit(struct super_block *sb)
930 {
931         atomic_inc(&EXT4_SB(sb)->s_warning_count);
932         return ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
933                             "EXT4-fs warning");
934 }
935
936 void __ext4_warning(struct super_block *sb, const char *function,
937                     unsigned int line, const char *fmt, ...)
938 {
939         struct va_format vaf;
940         va_list args;
941
942         if (!ext4_warning_ratelimit(sb))
943                 return;
944
945         va_start(args, fmt);
946         vaf.fmt = fmt;
947         vaf.va = &args;
948         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
949                sb->s_id, function, line, &vaf);
950         va_end(args);
951 }
952
953 void __ext4_warning_inode(const struct inode *inode, const char *function,
954                           unsigned int line, const char *fmt, ...)
955 {
956         struct va_format vaf;
957         va_list args;
958
959         if (!ext4_warning_ratelimit(inode->i_sb))
960                 return;
961
962         va_start(args, fmt);
963         vaf.fmt = fmt;
964         vaf.va = &args;
965         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
966                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
967                function, line, inode->i_ino, current->comm, &vaf);
968         va_end(args);
969 }
970
971 void __ext4_grp_locked_error(const char *function, unsigned int line,
972                              struct super_block *sb, ext4_group_t grp,
973                              unsigned long ino, ext4_fsblk_t block,
974                              const char *fmt, ...)
975 __releases(bitlock)
976 __acquires(bitlock)
977 {
978         struct va_format vaf;
979         va_list args;
980
981         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
982                 return;
983
984         trace_ext4_error(sb, function, line);
985         __save_error_info(sb, EFSCORRUPTED, ino, block, function, line);
986
987         if (ext4_error_ratelimit(sb)) {
988                 va_start(args, fmt);
989                 vaf.fmt = fmt;
990                 vaf.va = &args;
991                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
992                        sb->s_id, function, line, grp);
993                 if (ino)
994                         printk(KERN_CONT "inode %lu: ", ino);
995                 if (block)
996                         printk(KERN_CONT "block %llu:",
997                                (unsigned long long) block);
998                 printk(KERN_CONT "%pV\n", &vaf);
999                 va_end(args);
1000         }
1001
1002         if (test_opt(sb, WARN_ON_ERROR))
1003                 WARN_ON_ONCE(1);
1004
1005         if (test_opt(sb, ERRORS_CONT)) {
1006                 ext4_commit_super(sb, 0);
1007                 return;
1008         }
1009
1010         ext4_unlock_group(sb, grp);
1011         ext4_commit_super(sb, 1);
1012         ext4_handle_error(sb);
1013         /*
1014          * We only get here in the ERRORS_RO case; relocking the group
1015          * may be dangerous, but nothing bad will happen since the
1016          * filesystem will have already been marked read/only and the
1017          * journal has been aborted.  We return 1 as a hint to callers
1018          * who might what to use the return value from
1019          * ext4_grp_locked_error() to distinguish between the
1020          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
1021          * aggressively from the ext4 function in question, with a
1022          * more appropriate error code.
1023          */
1024         ext4_lock_group(sb, grp);
1025         return;
1026 }
1027
1028 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
1029                                      ext4_group_t group,
1030                                      unsigned int flags)
1031 {
1032         struct ext4_sb_info *sbi = EXT4_SB(sb);
1033         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
1034         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
1035         int ret;
1036
1037         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
1038                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
1039                                             &grp->bb_state);
1040                 if (!ret)
1041                         percpu_counter_sub(&sbi->s_freeclusters_counter,
1042                                            grp->bb_free);
1043         }
1044
1045         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
1046                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
1047                                             &grp->bb_state);
1048                 if (!ret && gdp) {
1049                         int count;
1050
1051                         count = ext4_free_inodes_count(sb, gdp);
1052                         percpu_counter_sub(&sbi->s_freeinodes_counter,
1053                                            count);
1054                 }
1055         }
1056 }
1057
1058 void ext4_update_dynamic_rev(struct super_block *sb)
1059 {
1060         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
1061
1062         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
1063                 return;
1064
1065         ext4_warning(sb,
1066                      "updating to rev %d because of new feature flag, "
1067                      "running e2fsck is recommended",
1068                      EXT4_DYNAMIC_REV);
1069
1070         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
1071         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
1072         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
1073         /* leave es->s_feature_*compat flags alone */
1074         /* es->s_uuid will be set by e2fsck if empty */
1075
1076         /*
1077          * The rest of the superblock fields should be zero, and if not it
1078          * means they are likely already in use, so leave them alone.  We
1079          * can leave it up to e2fsck to clean up any inconsistencies there.
1080          */
1081 }
1082
1083 /*
1084  * Open the external journal device
1085  */
1086 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
1087 {
1088         struct block_device *bdev;
1089
1090         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
1091         if (IS_ERR(bdev))
1092                 goto fail;
1093         return bdev;
1094
1095 fail:
1096         ext4_msg(sb, KERN_ERR,
1097                  "failed to open journal device unknown-block(%u,%u) %ld",
1098                  MAJOR(dev), MINOR(dev), PTR_ERR(bdev));
1099         return NULL;
1100 }
1101
1102 /*
1103  * Release the journal device
1104  */
1105 static void ext4_blkdev_put(struct block_device *bdev)
1106 {
1107         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
1108 }
1109
1110 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
1111 {
1112         struct block_device *bdev;
1113         bdev = sbi->s_journal_bdev;
1114         if (bdev) {
1115                 ext4_blkdev_put(bdev);
1116                 sbi->s_journal_bdev = NULL;
1117         }
1118 }
1119
1120 static inline struct inode *orphan_list_entry(struct list_head *l)
1121 {
1122         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
1123 }
1124
1125 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
1126 {
1127         struct list_head *l;
1128
1129         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
1130                  le32_to_cpu(sbi->s_es->s_last_orphan));
1131
1132         printk(KERN_ERR "sb_info orphan list:\n");
1133         list_for_each(l, &sbi->s_orphan) {
1134                 struct inode *inode = orphan_list_entry(l);
1135                 printk(KERN_ERR "  "
1136                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
1137                        inode->i_sb->s_id, inode->i_ino, inode,
1138                        inode->i_mode, inode->i_nlink,
1139                        NEXT_ORPHAN(inode));
1140         }
1141 }
1142
1143 #ifdef CONFIG_QUOTA
1144 static int ext4_quota_off(struct super_block *sb, int type);
1145
1146 static inline void ext4_quota_off_umount(struct super_block *sb)
1147 {
1148         int type;
1149
1150         /* Use our quota_off function to clear inode flags etc. */
1151         for (type = 0; type < EXT4_MAXQUOTAS; type++)
1152                 ext4_quota_off(sb, type);
1153 }
1154
1155 /*
1156  * This is a helper function which is used in the mount/remount
1157  * codepaths (which holds s_umount) to fetch the quota file name.
1158  */
1159 static inline char *get_qf_name(struct super_block *sb,
1160                                 struct ext4_sb_info *sbi,
1161                                 int type)
1162 {
1163         return rcu_dereference_protected(sbi->s_qf_names[type],
1164                                          lockdep_is_held(&sb->s_umount));
1165 }
1166 #else
1167 static inline void ext4_quota_off_umount(struct super_block *sb)
1168 {
1169 }
1170 #endif
1171
1172 static void ext4_put_super(struct super_block *sb)
1173 {
1174         struct ext4_sb_info *sbi = EXT4_SB(sb);
1175         struct ext4_super_block *es = sbi->s_es;
1176         struct buffer_head **group_desc;
1177         struct flex_groups **flex_groups;
1178         int aborted = 0;
1179         int i, err;
1180
1181         ext4_unregister_li_request(sb);
1182         ext4_quota_off_umount(sb);
1183
1184         destroy_workqueue(sbi->rsv_conversion_wq);
1185
1186         /*
1187          * Unregister sysfs before destroying jbd2 journal.
1188          * Since we could still access attr_journal_task attribute via sysfs
1189          * path which could have sbi->s_journal->j_task as NULL
1190          */
1191         ext4_unregister_sysfs(sb);
1192
1193         if (sbi->s_journal) {
1194                 aborted = is_journal_aborted(sbi->s_journal);
1195                 err = jbd2_journal_destroy(sbi->s_journal);
1196                 sbi->s_journal = NULL;
1197                 if ((err < 0) && !aborted) {
1198                         ext4_abort(sb, -err, "Couldn't clean up the journal");
1199                 }
1200         }
1201
1202         ext4_es_unregister_shrinker(sbi);
1203         del_timer_sync(&sbi->s_err_report);
1204         ext4_release_system_zone(sb);
1205         ext4_mb_release(sb);
1206         ext4_ext_release(sb);
1207
1208         if (!sb_rdonly(sb) && !aborted) {
1209                 ext4_clear_feature_journal_needs_recovery(sb);
1210                 es->s_state = cpu_to_le16(sbi->s_mount_state);
1211         }
1212         if (!sb_rdonly(sb))
1213                 ext4_commit_super(sb, 1);
1214
1215         rcu_read_lock();
1216         group_desc = rcu_dereference(sbi->s_group_desc);
1217         for (i = 0; i < sbi->s_gdb_count; i++)
1218                 brelse(group_desc[i]);
1219         kvfree(group_desc);
1220         flex_groups = rcu_dereference(sbi->s_flex_groups);
1221         if (flex_groups) {
1222                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
1223                         kvfree(flex_groups[i]);
1224                 kvfree(flex_groups);
1225         }
1226         rcu_read_unlock();
1227         percpu_counter_destroy(&sbi->s_freeclusters_counter);
1228         percpu_counter_destroy(&sbi->s_freeinodes_counter);
1229         percpu_counter_destroy(&sbi->s_dirs_counter);
1230         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
1231         percpu_free_rwsem(&sbi->s_writepages_rwsem);
1232 #ifdef CONFIG_QUOTA
1233         for (i = 0; i < EXT4_MAXQUOTAS; i++)
1234                 kfree(get_qf_name(sb, sbi, i));
1235 #endif
1236
1237         /* Debugging code just in case the in-memory inode orphan list
1238          * isn't empty.  The on-disk one can be non-empty if we've
1239          * detected an error and taken the fs readonly, but the
1240          * in-memory list had better be clean by this point. */
1241         if (!list_empty(&sbi->s_orphan))
1242                 dump_orphan_list(sb, sbi);
1243         J_ASSERT(list_empty(&sbi->s_orphan));
1244
1245         sync_blockdev(sb->s_bdev);
1246         invalidate_bdev(sb->s_bdev);
1247         if (sbi->s_journal_bdev && sbi->s_journal_bdev != sb->s_bdev) {
1248                 /*
1249                  * Invalidate the journal device's buffers.  We don't want them
1250                  * floating about in memory - the physical journal device may
1251                  * hotswapped, and it breaks the `ro-after' testing code.
1252                  */
1253                 sync_blockdev(sbi->s_journal_bdev);
1254                 invalidate_bdev(sbi->s_journal_bdev);
1255                 ext4_blkdev_remove(sbi);
1256         }
1257
1258         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1259         sbi->s_ea_inode_cache = NULL;
1260
1261         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1262         sbi->s_ea_block_cache = NULL;
1263
1264         if (sbi->s_mmp_tsk)
1265                 kthread_stop(sbi->s_mmp_tsk);
1266         brelse(sbi->s_sbh);
1267         sb->s_fs_info = NULL;
1268         /*
1269          * Now that we are completely done shutting down the
1270          * superblock, we need to actually destroy the kobject.
1271          */
1272         kobject_put(&sbi->s_kobj);
1273         wait_for_completion(&sbi->s_kobj_unregister);
1274         if (sbi->s_chksum_driver)
1275                 crypto_free_shash(sbi->s_chksum_driver);
1276         kfree(sbi->s_blockgroup_lock);
1277         fs_put_dax(sbi->s_daxdev);
1278         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
1279 #ifdef CONFIG_UNICODE
1280         utf8_unload(sb->s_encoding);
1281 #endif
1282         kfree(sbi);
1283 }
1284
1285 static struct kmem_cache *ext4_inode_cachep;
1286
1287 /*
1288  * Called inside transaction, so use GFP_NOFS
1289  */
1290 static struct inode *ext4_alloc_inode(struct super_block *sb)
1291 {
1292         struct ext4_inode_info *ei;
1293
1294         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1295         if (!ei)
1296                 return NULL;
1297
1298         inode_set_iversion(&ei->vfs_inode, 1);
1299         spin_lock_init(&ei->i_raw_lock);
1300         INIT_LIST_HEAD(&ei->i_prealloc_list);
1301         atomic_set(&ei->i_prealloc_active, 0);
1302         spin_lock_init(&ei->i_prealloc_lock);
1303         ext4_es_init_tree(&ei->i_es_tree);
1304         rwlock_init(&ei->i_es_lock);
1305         INIT_LIST_HEAD(&ei->i_es_list);
1306         ei->i_es_all_nr = 0;
1307         ei->i_es_shk_nr = 0;
1308         ei->i_es_shrink_lblk = 0;
1309         ei->i_reserved_data_blocks = 0;
1310         spin_lock_init(&(ei->i_block_reservation_lock));
1311         ext4_init_pending_tree(&ei->i_pending_tree);
1312 #ifdef CONFIG_QUOTA
1313         ei->i_reserved_quota = 0;
1314         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1315 #endif
1316         ei->jinode = NULL;
1317         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1318         spin_lock_init(&ei->i_completed_io_lock);
1319         ei->i_sync_tid = 0;
1320         ei->i_datasync_tid = 0;
1321         atomic_set(&ei->i_unwritten, 0);
1322         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1323         ext4_fc_init_inode(&ei->vfs_inode);
1324         mutex_init(&ei->i_fc_lock);
1325         return &ei->vfs_inode;
1326 }
1327
1328 static int ext4_drop_inode(struct inode *inode)
1329 {
1330         int drop = generic_drop_inode(inode);
1331
1332         if (!drop)
1333                 drop = fscrypt_drop_inode(inode);
1334
1335         trace_ext4_drop_inode(inode, drop);
1336         return drop;
1337 }
1338
1339 static void ext4_free_in_core_inode(struct inode *inode)
1340 {
1341         fscrypt_free_inode(inode);
1342         if (!list_empty(&(EXT4_I(inode)->i_fc_list))) {
1343                 pr_warn("%s: inode %ld still in fc list",
1344                         __func__, inode->i_ino);
1345         }
1346         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1347 }
1348
1349 static void ext4_destroy_inode(struct inode *inode)
1350 {
1351         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1352                 ext4_msg(inode->i_sb, KERN_ERR,
1353                          "Inode %lu (%p): orphan list check failed!",
1354                          inode->i_ino, EXT4_I(inode));
1355                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1356                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1357                                 true);
1358                 dump_stack();
1359         }
1360 }
1361
1362 static void init_once(void *foo)
1363 {
1364         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1365
1366         INIT_LIST_HEAD(&ei->i_orphan);
1367         init_rwsem(&ei->xattr_sem);
1368         init_rwsem(&ei->i_data_sem);
1369         init_rwsem(&ei->i_mmap_sem);
1370         inode_init_once(&ei->vfs_inode);
1371         ext4_fc_init_inode(&ei->vfs_inode);
1372 }
1373
1374 static int __init init_inodecache(void)
1375 {
1376         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1377                                 sizeof(struct ext4_inode_info), 0,
1378                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1379                                         SLAB_ACCOUNT),
1380                                 offsetof(struct ext4_inode_info, i_data),
1381                                 sizeof_field(struct ext4_inode_info, i_data),
1382                                 init_once);
1383         if (ext4_inode_cachep == NULL)
1384                 return -ENOMEM;
1385         return 0;
1386 }
1387
1388 static void destroy_inodecache(void)
1389 {
1390         /*
1391          * Make sure all delayed rcu free inodes are flushed before we
1392          * destroy cache.
1393          */
1394         rcu_barrier();
1395         kmem_cache_destroy(ext4_inode_cachep);
1396 }
1397
1398 void ext4_clear_inode(struct inode *inode)
1399 {
1400         ext4_fc_del(inode);
1401         invalidate_inode_buffers(inode);
1402         clear_inode(inode);
1403         ext4_discard_preallocations(inode, 0);
1404         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1405         dquot_drop(inode);
1406         if (EXT4_I(inode)->jinode) {
1407                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1408                                                EXT4_I(inode)->jinode);
1409                 jbd2_free_inode(EXT4_I(inode)->jinode);
1410                 EXT4_I(inode)->jinode = NULL;
1411         }
1412         fscrypt_put_encryption_info(inode);
1413         fsverity_cleanup_inode(inode);
1414 }
1415
1416 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1417                                         u64 ino, u32 generation)
1418 {
1419         struct inode *inode;
1420
1421         /*
1422          * Currently we don't know the generation for parent directory, so
1423          * a generation of 0 means "accept any"
1424          */
1425         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1426         if (IS_ERR(inode))
1427                 return ERR_CAST(inode);
1428         if (generation && inode->i_generation != generation) {
1429                 iput(inode);
1430                 return ERR_PTR(-ESTALE);
1431         }
1432
1433         return inode;
1434 }
1435
1436 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1437                                         int fh_len, int fh_type)
1438 {
1439         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1440                                     ext4_nfs_get_inode);
1441 }
1442
1443 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1444                                         int fh_len, int fh_type)
1445 {
1446         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1447                                     ext4_nfs_get_inode);
1448 }
1449
1450 static int ext4_nfs_commit_metadata(struct inode *inode)
1451 {
1452         struct writeback_control wbc = {
1453                 .sync_mode = WB_SYNC_ALL
1454         };
1455
1456         trace_ext4_nfs_commit_metadata(inode);
1457         return ext4_write_inode(inode, &wbc);
1458 }
1459
1460 /*
1461  * Try to release metadata pages (indirect blocks, directories) which are
1462  * mapped via the block device.  Since these pages could have journal heads
1463  * which would prevent try_to_free_buffers() from freeing them, we must use
1464  * jbd2 layer's try_to_free_buffers() function to release them.
1465  */
1466 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1467                                  gfp_t wait)
1468 {
1469         journal_t *journal = EXT4_SB(sb)->s_journal;
1470
1471         WARN_ON(PageChecked(page));
1472         if (!page_has_buffers(page))
1473                 return 0;
1474         if (journal)
1475                 return jbd2_journal_try_to_free_buffers(journal, page);
1476
1477         return try_to_free_buffers(page);
1478 }
1479
1480 #ifdef CONFIG_FS_ENCRYPTION
1481 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1482 {
1483         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1484                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1485 }
1486
1487 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1488                                                         void *fs_data)
1489 {
1490         handle_t *handle = fs_data;
1491         int res, res2, credits, retries = 0;
1492
1493         /*
1494          * Encrypting the root directory is not allowed because e2fsck expects
1495          * lost+found to exist and be unencrypted, and encrypting the root
1496          * directory would imply encrypting the lost+found directory as well as
1497          * the filename "lost+found" itself.
1498          */
1499         if (inode->i_ino == EXT4_ROOT_INO)
1500                 return -EPERM;
1501
1502         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1503                 return -EINVAL;
1504
1505         if (ext4_test_inode_flag(inode, EXT4_INODE_DAX))
1506                 return -EOPNOTSUPP;
1507
1508         res = ext4_convert_inline_data(inode);
1509         if (res)
1510                 return res;
1511
1512         /*
1513          * If a journal handle was specified, then the encryption context is
1514          * being set on a new inode via inheritance and is part of a larger
1515          * transaction to create the inode.  Otherwise the encryption context is
1516          * being set on an existing inode in its own transaction.  Only in the
1517          * latter case should the "retry on ENOSPC" logic be used.
1518          */
1519
1520         if (handle) {
1521                 res = ext4_xattr_set_handle(handle, inode,
1522                                             EXT4_XATTR_INDEX_ENCRYPTION,
1523                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1524                                             ctx, len, 0);
1525                 if (!res) {
1526                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1527                         ext4_clear_inode_state(inode,
1528                                         EXT4_STATE_MAY_INLINE_DATA);
1529                         /*
1530                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1531                          * S_DAX may be disabled
1532                          */
1533                         ext4_set_inode_flags(inode, false);
1534                 }
1535                 return res;
1536         }
1537
1538         res = dquot_initialize(inode);
1539         if (res)
1540                 return res;
1541 retry:
1542         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1543                                      &credits);
1544         if (res)
1545                 return res;
1546
1547         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1548         if (IS_ERR(handle))
1549                 return PTR_ERR(handle);
1550
1551         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1552                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1553                                     ctx, len, 0);
1554         if (!res) {
1555                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1556                 /*
1557                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1558                  * S_DAX may be disabled
1559                  */
1560                 ext4_set_inode_flags(inode, false);
1561                 res = ext4_mark_inode_dirty(handle, inode);
1562                 if (res)
1563                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1564         }
1565         res2 = ext4_journal_stop(handle);
1566
1567         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1568                 goto retry;
1569         if (!res)
1570                 res = res2;
1571         return res;
1572 }
1573
1574 static const union fscrypt_policy *ext4_get_dummy_policy(struct super_block *sb)
1575 {
1576         return EXT4_SB(sb)->s_dummy_enc_policy.policy;
1577 }
1578
1579 static bool ext4_has_stable_inodes(struct super_block *sb)
1580 {
1581         return ext4_has_feature_stable_inodes(sb);
1582 }
1583
1584 static void ext4_get_ino_and_lblk_bits(struct super_block *sb,
1585                                        int *ino_bits_ret, int *lblk_bits_ret)
1586 {
1587         *ino_bits_ret = 8 * sizeof(EXT4_SB(sb)->s_es->s_inodes_count);
1588         *lblk_bits_ret = 8 * sizeof(ext4_lblk_t);
1589 }
1590
1591 static const struct fscrypt_operations ext4_cryptops = {
1592         .key_prefix             = "ext4:",
1593         .get_context            = ext4_get_context,
1594         .set_context            = ext4_set_context,
1595         .get_dummy_policy       = ext4_get_dummy_policy,
1596         .empty_dir              = ext4_empty_dir,
1597         .max_namelen            = EXT4_NAME_LEN,
1598         .has_stable_inodes      = ext4_has_stable_inodes,
1599         .get_ino_and_lblk_bits  = ext4_get_ino_and_lblk_bits,
1600 };
1601 #endif
1602
1603 #ifdef CONFIG_QUOTA
1604 static const char * const quotatypes[] = INITQFNAMES;
1605 #define QTYPE2NAME(t) (quotatypes[t])
1606
1607 static int ext4_write_dquot(struct dquot *dquot);
1608 static int ext4_acquire_dquot(struct dquot *dquot);
1609 static int ext4_release_dquot(struct dquot *dquot);
1610 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1611 static int ext4_write_info(struct super_block *sb, int type);
1612 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1613                          const struct path *path);
1614 static int ext4_quota_on_mount(struct super_block *sb, int type);
1615 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1616                                size_t len, loff_t off);
1617 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1618                                 const char *data, size_t len, loff_t off);
1619 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1620                              unsigned int flags);
1621 static int ext4_enable_quotas(struct super_block *sb);
1622
1623 static struct dquot **ext4_get_dquots(struct inode *inode)
1624 {
1625         return EXT4_I(inode)->i_dquot;
1626 }
1627
1628 static const struct dquot_operations ext4_quota_operations = {
1629         .get_reserved_space     = ext4_get_reserved_space,
1630         .write_dquot            = ext4_write_dquot,
1631         .acquire_dquot          = ext4_acquire_dquot,
1632         .release_dquot          = ext4_release_dquot,
1633         .mark_dirty             = ext4_mark_dquot_dirty,
1634         .write_info             = ext4_write_info,
1635         .alloc_dquot            = dquot_alloc,
1636         .destroy_dquot          = dquot_destroy,
1637         .get_projid             = ext4_get_projid,
1638         .get_inode_usage        = ext4_get_inode_usage,
1639         .get_next_id            = dquot_get_next_id,
1640 };
1641
1642 static const struct quotactl_ops ext4_qctl_operations = {
1643         .quota_on       = ext4_quota_on,
1644         .quota_off      = ext4_quota_off,
1645         .quota_sync     = dquot_quota_sync,
1646         .get_state      = dquot_get_state,
1647         .set_info       = dquot_set_dqinfo,
1648         .get_dqblk      = dquot_get_dqblk,
1649         .set_dqblk      = dquot_set_dqblk,
1650         .get_nextdqblk  = dquot_get_next_dqblk,
1651 };
1652 #endif
1653
1654 static const struct super_operations ext4_sops = {
1655         .alloc_inode    = ext4_alloc_inode,
1656         .free_inode     = ext4_free_in_core_inode,
1657         .destroy_inode  = ext4_destroy_inode,
1658         .write_inode    = ext4_write_inode,
1659         .dirty_inode    = ext4_dirty_inode,
1660         .drop_inode     = ext4_drop_inode,
1661         .evict_inode    = ext4_evict_inode,
1662         .put_super      = ext4_put_super,
1663         .sync_fs        = ext4_sync_fs,
1664         .freeze_fs      = ext4_freeze,
1665         .unfreeze_fs    = ext4_unfreeze,
1666         .statfs         = ext4_statfs,
1667         .remount_fs     = ext4_remount,
1668         .show_options   = ext4_show_options,
1669 #ifdef CONFIG_QUOTA
1670         .quota_read     = ext4_quota_read,
1671         .quota_write    = ext4_quota_write,
1672         .get_dquots     = ext4_get_dquots,
1673 #endif
1674         .bdev_try_to_free_page = bdev_try_to_free_page,
1675 };
1676
1677 static const struct export_operations ext4_export_ops = {
1678         .fh_to_dentry = ext4_fh_to_dentry,
1679         .fh_to_parent = ext4_fh_to_parent,
1680         .get_parent = ext4_get_parent,
1681         .commit_metadata = ext4_nfs_commit_metadata,
1682 };
1683
1684 enum {
1685         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1686         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1687         Opt_nouid32, Opt_debug, Opt_removed,
1688         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1689         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1690         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1691         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1692         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1693         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1694         Opt_inlinecrypt,
1695         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1696         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1697         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1698         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version,
1699         Opt_dax, Opt_dax_always, Opt_dax_inode, Opt_dax_never,
1700         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1701         Opt_nowarn_on_error, Opt_mblk_io_submit,
1702         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1703         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1704         Opt_inode_readahead_blks, Opt_journal_ioprio,
1705         Opt_dioread_nolock, Opt_dioread_lock,
1706         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1707         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1708         Opt_prefetch_block_bitmaps,
1709 #ifdef CONFIG_EXT4_DEBUG
1710         Opt_fc_debug_max_replay, Opt_fc_debug_force
1711 #endif
1712 };
1713
1714 static const match_table_t tokens = {
1715         {Opt_bsd_df, "bsddf"},
1716         {Opt_minix_df, "minixdf"},
1717         {Opt_grpid, "grpid"},
1718         {Opt_grpid, "bsdgroups"},
1719         {Opt_nogrpid, "nogrpid"},
1720         {Opt_nogrpid, "sysvgroups"},
1721         {Opt_resgid, "resgid=%u"},
1722         {Opt_resuid, "resuid=%u"},
1723         {Opt_sb, "sb=%u"},
1724         {Opt_err_cont, "errors=continue"},
1725         {Opt_err_panic, "errors=panic"},
1726         {Opt_err_ro, "errors=remount-ro"},
1727         {Opt_nouid32, "nouid32"},
1728         {Opt_debug, "debug"},
1729         {Opt_removed, "oldalloc"},
1730         {Opt_removed, "orlov"},
1731         {Opt_user_xattr, "user_xattr"},
1732         {Opt_nouser_xattr, "nouser_xattr"},
1733         {Opt_acl, "acl"},
1734         {Opt_noacl, "noacl"},
1735         {Opt_noload, "norecovery"},
1736         {Opt_noload, "noload"},
1737         {Opt_removed, "nobh"},
1738         {Opt_removed, "bh"},
1739         {Opt_commit, "commit=%u"},
1740         {Opt_min_batch_time, "min_batch_time=%u"},
1741         {Opt_max_batch_time, "max_batch_time=%u"},
1742         {Opt_journal_dev, "journal_dev=%u"},
1743         {Opt_journal_path, "journal_path=%s"},
1744         {Opt_journal_checksum, "journal_checksum"},
1745         {Opt_nojournal_checksum, "nojournal_checksum"},
1746         {Opt_journal_async_commit, "journal_async_commit"},
1747         {Opt_abort, "abort"},
1748         {Opt_data_journal, "data=journal"},
1749         {Opt_data_ordered, "data=ordered"},
1750         {Opt_data_writeback, "data=writeback"},
1751         {Opt_data_err_abort, "data_err=abort"},
1752         {Opt_data_err_ignore, "data_err=ignore"},
1753         {Opt_offusrjquota, "usrjquota="},
1754         {Opt_usrjquota, "usrjquota=%s"},
1755         {Opt_offgrpjquota, "grpjquota="},
1756         {Opt_grpjquota, "grpjquota=%s"},
1757         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1758         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1759         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1760         {Opt_grpquota, "grpquota"},
1761         {Opt_noquota, "noquota"},
1762         {Opt_quota, "quota"},
1763         {Opt_usrquota, "usrquota"},
1764         {Opt_prjquota, "prjquota"},
1765         {Opt_barrier, "barrier=%u"},
1766         {Opt_barrier, "barrier"},
1767         {Opt_nobarrier, "nobarrier"},
1768         {Opt_i_version, "i_version"},
1769         {Opt_dax, "dax"},
1770         {Opt_dax_always, "dax=always"},
1771         {Opt_dax_inode, "dax=inode"},
1772         {Opt_dax_never, "dax=never"},
1773         {Opt_stripe, "stripe=%u"},
1774         {Opt_delalloc, "delalloc"},
1775         {Opt_warn_on_error, "warn_on_error"},
1776         {Opt_nowarn_on_error, "nowarn_on_error"},
1777         {Opt_lazytime, "lazytime"},
1778         {Opt_nolazytime, "nolazytime"},
1779         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1780         {Opt_nodelalloc, "nodelalloc"},
1781         {Opt_removed, "mblk_io_submit"},
1782         {Opt_removed, "nomblk_io_submit"},
1783         {Opt_block_validity, "block_validity"},
1784         {Opt_noblock_validity, "noblock_validity"},
1785         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1786         {Opt_journal_ioprio, "journal_ioprio=%u"},
1787         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1788         {Opt_auto_da_alloc, "auto_da_alloc"},
1789         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1790         {Opt_dioread_nolock, "dioread_nolock"},
1791         {Opt_dioread_lock, "nodioread_nolock"},
1792         {Opt_dioread_lock, "dioread_lock"},
1793         {Opt_discard, "discard"},
1794         {Opt_nodiscard, "nodiscard"},
1795         {Opt_init_itable, "init_itable=%u"},
1796         {Opt_init_itable, "init_itable"},
1797         {Opt_noinit_itable, "noinit_itable"},
1798 #ifdef CONFIG_EXT4_DEBUG
1799         {Opt_fc_debug_force, "fc_debug_force"},
1800         {Opt_fc_debug_max_replay, "fc_debug_max_replay=%u"},
1801 #endif
1802         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1803         {Opt_test_dummy_encryption, "test_dummy_encryption=%s"},
1804         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1805         {Opt_inlinecrypt, "inlinecrypt"},
1806         {Opt_nombcache, "nombcache"},
1807         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1808         {Opt_prefetch_block_bitmaps, "prefetch_block_bitmaps"},
1809         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1810         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1811         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1812         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1813         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1814         {Opt_err, NULL},
1815 };
1816
1817 static ext4_fsblk_t get_sb_block(void **data)
1818 {
1819         ext4_fsblk_t    sb_block;
1820         char            *options = (char *) *data;
1821
1822         if (!options || strncmp(options, "sb=", 3) != 0)
1823                 return 1;       /* Default location */
1824
1825         options += 3;
1826         /* TODO: use simple_strtoll with >32bit ext4 */
1827         sb_block = simple_strtoul(options, &options, 0);
1828         if (*options && *options != ',') {
1829                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1830                        (char *) *data);
1831                 return 1;
1832         }
1833         if (*options == ',')
1834                 options++;
1835         *data = (void *) options;
1836
1837         return sb_block;
1838 }
1839
1840 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1841 static const char deprecated_msg[] =
1842         "Mount option \"%s\" will be removed by %s\n"
1843         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1844
1845 #ifdef CONFIG_QUOTA
1846 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1847 {
1848         struct ext4_sb_info *sbi = EXT4_SB(sb);
1849         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1850         int ret = -1;
1851
1852         if (sb_any_quota_loaded(sb) && !old_qname) {
1853                 ext4_msg(sb, KERN_ERR,
1854                         "Cannot change journaled "
1855                         "quota options when quota turned on");
1856                 return -1;
1857         }
1858         if (ext4_has_feature_quota(sb)) {
1859                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1860                          "ignored when QUOTA feature is enabled");
1861                 return 1;
1862         }
1863         qname = match_strdup(args);
1864         if (!qname) {
1865                 ext4_msg(sb, KERN_ERR,
1866                         "Not enough memory for storing quotafile name");
1867                 return -1;
1868         }
1869         if (old_qname) {
1870                 if (strcmp(old_qname, qname) == 0)
1871                         ret = 1;
1872                 else
1873                         ext4_msg(sb, KERN_ERR,
1874                                  "%s quota file already specified",
1875                                  QTYPE2NAME(qtype));
1876                 goto errout;
1877         }
1878         if (strchr(qname, '/')) {
1879                 ext4_msg(sb, KERN_ERR,
1880                         "quotafile must be on filesystem root");
1881                 goto errout;
1882         }
1883         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1884         set_opt(sb, QUOTA);
1885         return 1;
1886 errout:
1887         kfree(qname);
1888         return ret;
1889 }
1890
1891 static int clear_qf_name(struct super_block *sb, int qtype)
1892 {
1893
1894         struct ext4_sb_info *sbi = EXT4_SB(sb);
1895         char *old_qname = get_qf_name(sb, sbi, qtype);
1896
1897         if (sb_any_quota_loaded(sb) && old_qname) {
1898                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1899                         " when quota turned on");
1900                 return -1;
1901         }
1902         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1903         synchronize_rcu();
1904         kfree(old_qname);
1905         return 1;
1906 }
1907 #endif
1908
1909 #define MOPT_SET        0x0001
1910 #define MOPT_CLEAR      0x0002
1911 #define MOPT_NOSUPPORT  0x0004
1912 #define MOPT_EXPLICIT   0x0008
1913 #define MOPT_CLEAR_ERR  0x0010
1914 #define MOPT_GTE0       0x0020
1915 #ifdef CONFIG_QUOTA
1916 #define MOPT_Q          0
1917 #define MOPT_QFMT       0x0040
1918 #else
1919 #define MOPT_Q          MOPT_NOSUPPORT
1920 #define MOPT_QFMT       MOPT_NOSUPPORT
1921 #endif
1922 #define MOPT_DATAJ      0x0080
1923 #define MOPT_NO_EXT2    0x0100
1924 #define MOPT_NO_EXT3    0x0200
1925 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1926 #define MOPT_STRING     0x0400
1927 #define MOPT_SKIP       0x0800
1928 #define MOPT_2          0x1000
1929
1930 static const struct mount_opts {
1931         int     token;
1932         int     mount_opt;
1933         int     flags;
1934 } ext4_mount_opts[] = {
1935         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1936         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1937         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1938         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1939         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1940         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1941         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1942          MOPT_EXT4_ONLY | MOPT_SET},
1943         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1944          MOPT_EXT4_ONLY | MOPT_CLEAR},
1945         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1946         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1947         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1948          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1949         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1950          MOPT_EXT4_ONLY | MOPT_CLEAR},
1951         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1952         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1953         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1954          MOPT_EXT4_ONLY | MOPT_CLEAR},
1955         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1956          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1957         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1958                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1959          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1960         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1961         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1962         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1963         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1964         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1965          MOPT_NO_EXT2},
1966         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1967          MOPT_NO_EXT2},
1968         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1969         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1970         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1971         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1972         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1973         {Opt_commit, 0, MOPT_GTE0},
1974         {Opt_max_batch_time, 0, MOPT_GTE0},
1975         {Opt_min_batch_time, 0, MOPT_GTE0},
1976         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1977         {Opt_init_itable, 0, MOPT_GTE0},
1978         {Opt_dax, EXT4_MOUNT_DAX_ALWAYS, MOPT_SET | MOPT_SKIP},
1979         {Opt_dax_always, EXT4_MOUNT_DAX_ALWAYS,
1980                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1981         {Opt_dax_inode, EXT4_MOUNT2_DAX_INODE,
1982                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1983         {Opt_dax_never, EXT4_MOUNT2_DAX_NEVER,
1984                 MOPT_EXT4_ONLY | MOPT_SET | MOPT_SKIP},
1985         {Opt_stripe, 0, MOPT_GTE0},
1986         {Opt_resuid, 0, MOPT_GTE0},
1987         {Opt_resgid, 0, MOPT_GTE0},
1988         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1989         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1990         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1991         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1992         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1993         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1994          MOPT_NO_EXT2 | MOPT_DATAJ},
1995         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1996         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1997 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1998         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1999         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
2000 #else
2001         {Opt_acl, 0, MOPT_NOSUPPORT},
2002         {Opt_noacl, 0, MOPT_NOSUPPORT},
2003 #endif
2004         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
2005         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
2006         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
2007         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
2008         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
2009                                                         MOPT_SET | MOPT_Q},
2010         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
2011                                                         MOPT_SET | MOPT_Q},
2012         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
2013                                                         MOPT_SET | MOPT_Q},
2014         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
2015                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
2016                                                         MOPT_CLEAR | MOPT_Q},
2017         {Opt_usrjquota, 0, MOPT_Q | MOPT_STRING},
2018         {Opt_grpjquota, 0, MOPT_Q | MOPT_STRING},
2019         {Opt_offusrjquota, 0, MOPT_Q},
2020         {Opt_offgrpjquota, 0, MOPT_Q},
2021         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
2022         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
2023         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
2024         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
2025         {Opt_test_dummy_encryption, 0, MOPT_STRING},
2026         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
2027         {Opt_prefetch_block_bitmaps, EXT4_MOUNT_PREFETCH_BLOCK_BITMAPS,
2028          MOPT_SET},
2029 #ifdef CONFIG_EXT4_DEBUG
2030         {Opt_fc_debug_force, EXT4_MOUNT2_JOURNAL_FAST_COMMIT,
2031          MOPT_SET | MOPT_2 | MOPT_EXT4_ONLY},
2032         {Opt_fc_debug_max_replay, 0, MOPT_GTE0},
2033 #endif
2034         {Opt_err, 0, 0}
2035 };
2036
2037 #ifdef CONFIG_UNICODE
2038 static const struct ext4_sb_encodings {
2039         __u16 magic;
2040         char *name;
2041         char *version;
2042 } ext4_sb_encoding_map[] = {
2043         {EXT4_ENC_UTF8_12_1, "utf8", "12.1.0"},
2044 };
2045
2046 static int ext4_sb_read_encoding(const struct ext4_super_block *es,
2047                                  const struct ext4_sb_encodings **encoding,
2048                                  __u16 *flags)
2049 {
2050         __u16 magic = le16_to_cpu(es->s_encoding);
2051         int i;
2052
2053         for (i = 0; i < ARRAY_SIZE(ext4_sb_encoding_map); i++)
2054                 if (magic == ext4_sb_encoding_map[i].magic)
2055                         break;
2056
2057         if (i >= ARRAY_SIZE(ext4_sb_encoding_map))
2058                 return -EINVAL;
2059
2060         *encoding = &ext4_sb_encoding_map[i];
2061         *flags = le16_to_cpu(es->s_encoding_flags);
2062
2063         return 0;
2064 }
2065 #endif
2066
2067 static int ext4_set_test_dummy_encryption(struct super_block *sb,
2068                                           const char *opt,
2069                                           const substring_t *arg,
2070                                           bool is_remount)
2071 {
2072 #ifdef CONFIG_FS_ENCRYPTION
2073         struct ext4_sb_info *sbi = EXT4_SB(sb);
2074         int err;
2075
2076         /*
2077          * This mount option is just for testing, and it's not worthwhile to
2078          * implement the extra complexity (e.g. RCU protection) that would be
2079          * needed to allow it to be set or changed during remount.  We do allow
2080          * it to be specified during remount, but only if there is no change.
2081          */
2082         if (is_remount && !sbi->s_dummy_enc_policy.policy) {
2083                 ext4_msg(sb, KERN_WARNING,
2084                          "Can't set test_dummy_encryption on remount");
2085                 return -1;
2086         }
2087         err = fscrypt_set_test_dummy_encryption(sb, arg->from,
2088                                                 &sbi->s_dummy_enc_policy);
2089         if (err) {
2090                 if (err == -EEXIST)
2091                         ext4_msg(sb, KERN_WARNING,
2092                                  "Can't change test_dummy_encryption on remount");
2093                 else if (err == -EINVAL)
2094                         ext4_msg(sb, KERN_WARNING,
2095                                  "Value of option \"%s\" is unrecognized", opt);
2096                 else
2097                         ext4_msg(sb, KERN_WARNING,
2098                                  "Error processing option \"%s\" [%d]",
2099                                  opt, err);
2100                 return -1;
2101         }
2102         ext4_msg(sb, KERN_WARNING, "Test dummy encryption mode enabled");
2103 #else
2104         ext4_msg(sb, KERN_WARNING,
2105                  "Test dummy encryption mount option ignored");
2106 #endif
2107         return 1;
2108 }
2109
2110 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
2111                             substring_t *args, unsigned long *journal_devnum,
2112                             unsigned int *journal_ioprio, int is_remount)
2113 {
2114         struct ext4_sb_info *sbi = EXT4_SB(sb);
2115         const struct mount_opts *m;
2116         kuid_t uid;
2117         kgid_t gid;
2118         int arg = 0;
2119
2120 #ifdef CONFIG_QUOTA
2121         if (token == Opt_usrjquota)
2122                 return set_qf_name(sb, USRQUOTA, &args[0]);
2123         else if (token == Opt_grpjquota)
2124                 return set_qf_name(sb, GRPQUOTA, &args[0]);
2125         else if (token == Opt_offusrjquota)
2126                 return clear_qf_name(sb, USRQUOTA);
2127         else if (token == Opt_offgrpjquota)
2128                 return clear_qf_name(sb, GRPQUOTA);
2129 #endif
2130         switch (token) {
2131         case Opt_noacl:
2132         case Opt_nouser_xattr:
2133                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
2134                 break;
2135         case Opt_sb:
2136                 return 1;       /* handled by get_sb_block() */
2137         case Opt_removed:
2138                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
2139                 return 1;
2140         case Opt_abort:
2141                 ext4_set_mount_flag(sb, EXT4_MF_FS_ABORTED);
2142                 return 1;
2143         case Opt_i_version:
2144                 sb->s_flags |= SB_I_VERSION;
2145                 return 1;
2146         case Opt_lazytime:
2147                 sb->s_flags |= SB_LAZYTIME;
2148                 return 1;
2149         case Opt_nolazytime:
2150                 sb->s_flags &= ~SB_LAZYTIME;
2151                 return 1;
2152         case Opt_inlinecrypt:
2153 #ifdef CONFIG_FS_ENCRYPTION_INLINE_CRYPT
2154                 sb->s_flags |= SB_INLINECRYPT;
2155 #else
2156                 ext4_msg(sb, KERN_ERR, "inline encryption not supported");
2157 #endif
2158                 return 1;
2159         }
2160
2161         for (m = ext4_mount_opts; m->token != Opt_err; m++)
2162                 if (token == m->token)
2163                         break;
2164
2165         if (m->token == Opt_err) {
2166                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
2167                          "or missing value", opt);
2168                 return -1;
2169         }
2170
2171         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
2172                 ext4_msg(sb, KERN_ERR,
2173                          "Mount option \"%s\" incompatible with ext2", opt);
2174                 return -1;
2175         }
2176         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
2177                 ext4_msg(sb, KERN_ERR,
2178                          "Mount option \"%s\" incompatible with ext3", opt);
2179                 return -1;
2180         }
2181
2182         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
2183                 return -1;
2184         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
2185                 return -1;
2186         if (m->flags & MOPT_EXPLICIT) {
2187                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
2188                         set_opt2(sb, EXPLICIT_DELALLOC);
2189                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
2190                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
2191                 } else
2192                         return -1;
2193         }
2194         if (m->flags & MOPT_CLEAR_ERR)
2195                 clear_opt(sb, ERRORS_MASK);
2196         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
2197                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
2198                          "options when quota turned on");
2199                 return -1;
2200         }
2201
2202         if (m->flags & MOPT_NOSUPPORT) {
2203                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
2204         } else if (token == Opt_commit) {
2205                 if (arg == 0)
2206                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
2207                 else if (arg > INT_MAX / HZ) {
2208                         ext4_msg(sb, KERN_ERR,
2209                                  "Invalid commit interval %d, "
2210                                  "must be smaller than %d",
2211                                  arg, INT_MAX / HZ);
2212                         return -1;
2213                 }
2214                 sbi->s_commit_interval = HZ * arg;
2215         } else if (token == Opt_debug_want_extra_isize) {
2216                 if ((arg & 1) ||
2217                     (arg < 4) ||
2218                     (arg > (sbi->s_inode_size - EXT4_GOOD_OLD_INODE_SIZE))) {
2219                         ext4_msg(sb, KERN_ERR,
2220                                  "Invalid want_extra_isize %d", arg);
2221                         return -1;
2222                 }
2223                 sbi->s_want_extra_isize = arg;
2224         } else if (token == Opt_max_batch_time) {
2225                 sbi->s_max_batch_time = arg;
2226         } else if (token == Opt_min_batch_time) {
2227                 sbi->s_min_batch_time = arg;
2228         } else if (token == Opt_inode_readahead_blks) {
2229                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
2230                         ext4_msg(sb, KERN_ERR,
2231                                  "EXT4-fs: inode_readahead_blks must be "
2232                                  "0 or a power of 2 smaller than 2^31");
2233                         return -1;
2234                 }
2235                 sbi->s_inode_readahead_blks = arg;
2236         } else if (token == Opt_init_itable) {
2237                 set_opt(sb, INIT_INODE_TABLE);
2238                 if (!args->from)
2239                         arg = EXT4_DEF_LI_WAIT_MULT;
2240                 sbi->s_li_wait_mult = arg;
2241         } else if (token == Opt_max_dir_size_kb) {
2242                 sbi->s_max_dir_size_kb = arg;
2243 #ifdef CONFIG_EXT4_DEBUG
2244         } else if (token == Opt_fc_debug_max_replay) {
2245                 sbi->s_fc_debug_max_replay = arg;
2246 #endif
2247         } else if (token == Opt_stripe) {
2248                 sbi->s_stripe = arg;
2249         } else if (token == Opt_resuid) {
2250                 uid = make_kuid(current_user_ns(), arg);
2251                 if (!uid_valid(uid)) {
2252                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
2253                         return -1;
2254                 }
2255                 sbi->s_resuid = uid;
2256         } else if (token == Opt_resgid) {
2257                 gid = make_kgid(current_user_ns(), arg);
2258                 if (!gid_valid(gid)) {
2259                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
2260                         return -1;
2261                 }
2262                 sbi->s_resgid = gid;
2263         } else if (token == Opt_journal_dev) {
2264                 if (is_remount) {
2265                         ext4_msg(sb, KERN_ERR,
2266                                  "Cannot specify journal on remount");
2267                         return -1;
2268                 }
2269                 *journal_devnum = arg;
2270         } else if (token == Opt_journal_path) {
2271                 char *journal_path;
2272                 struct inode *journal_inode;
2273                 struct path path;
2274                 int error;
2275
2276                 if (is_remount) {
2277                         ext4_msg(sb, KERN_ERR,
2278                                  "Cannot specify journal on remount");
2279                         return -1;
2280                 }
2281                 journal_path = match_strdup(&args[0]);
2282                 if (!journal_path) {
2283                         ext4_msg(sb, KERN_ERR, "error: could not dup "
2284                                 "journal device string");
2285                         return -1;
2286                 }
2287
2288                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
2289                 if (error) {
2290                         ext4_msg(sb, KERN_ERR, "error: could not find "
2291                                 "journal device path: error %d", error);
2292                         kfree(journal_path);
2293                         return -1;
2294                 }
2295
2296                 journal_inode = d_inode(path.dentry);
2297                 if (!S_ISBLK(journal_inode->i_mode)) {
2298                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
2299                                 "is not a block device", journal_path);
2300                         path_put(&path);
2301                         kfree(journal_path);
2302                         return -1;
2303                 }
2304
2305                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
2306                 path_put(&path);
2307                 kfree(journal_path);
2308         } else if (token == Opt_journal_ioprio) {
2309                 if (arg > 7) {
2310                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
2311                                  " (must be 0-7)");
2312                         return -1;
2313                 }
2314                 *journal_ioprio =
2315                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
2316         } else if (token == Opt_test_dummy_encryption) {
2317                 return ext4_set_test_dummy_encryption(sb, opt, &args[0],
2318                                                       is_remount);
2319         } else if (m->flags & MOPT_DATAJ) {
2320                 if (is_remount) {
2321                         if (!sbi->s_journal)
2322                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
2323                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
2324                                 ext4_msg(sb, KERN_ERR,
2325                                          "Cannot change data mode on remount");
2326                                 return -1;
2327                         }
2328                 } else {
2329                         clear_opt(sb, DATA_FLAGS);
2330                         sbi->s_mount_opt |= m->mount_opt;
2331                 }
2332 #ifdef CONFIG_QUOTA
2333         } else if (m->flags & MOPT_QFMT) {
2334                 if (sb_any_quota_loaded(sb) &&
2335                     sbi->s_jquota_fmt != m->mount_opt) {
2336                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
2337                                  "quota options when quota turned on");
2338                         return -1;
2339                 }
2340                 if (ext4_has_feature_quota(sb)) {
2341                         ext4_msg(sb, KERN_INFO,
2342                                  "Quota format mount options ignored "
2343                                  "when QUOTA feature is enabled");
2344                         return 1;
2345                 }
2346                 sbi->s_jquota_fmt = m->mount_opt;
2347 #endif
2348         } else if (token == Opt_dax || token == Opt_dax_always ||
2349                    token == Opt_dax_inode || token == Opt_dax_never) {
2350 #ifdef CONFIG_FS_DAX
2351                 switch (token) {
2352                 case Opt_dax:
2353                 case Opt_dax_always:
2354                         if (is_remount &&
2355                             (!(sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2356                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER))) {
2357                         fail_dax_change_remount:
2358                                 ext4_msg(sb, KERN_ERR, "can't change "
2359                                          "dax mount option while remounting");
2360                                 return -1;
2361                         }
2362                         if (is_remount &&
2363                             (test_opt(sb, DATA_FLAGS) ==
2364                              EXT4_MOUNT_JOURNAL_DATA)) {
2365                                     ext4_msg(sb, KERN_ERR, "can't mount with "
2366                                              "both data=journal and dax");
2367                                     return -1;
2368                         }
2369                         ext4_msg(sb, KERN_WARNING,
2370                                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
2371                         sbi->s_mount_opt |= EXT4_MOUNT_DAX_ALWAYS;
2372                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2373                         break;
2374                 case Opt_dax_never:
2375                         if (is_remount &&
2376                             (!(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2377                              (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS)))
2378                                 goto fail_dax_change_remount;
2379                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2380                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2381                         break;
2382                 case Opt_dax_inode:
2383                         if (is_remount &&
2384                             ((sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) ||
2385                              (sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_NEVER) ||
2386                              !(sbi->s_mount_opt2 & EXT4_MOUNT2_DAX_INODE)))
2387                                 goto fail_dax_change_remount;
2388                         sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2389                         sbi->s_mount_opt2 &= ~EXT4_MOUNT2_DAX_NEVER;
2390                         /* Strictly for printing options */
2391                         sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_INODE;
2392                         break;
2393                 }
2394 #else
2395                 ext4_msg(sb, KERN_INFO, "dax option not supported");
2396                 sbi->s_mount_opt2 |= EXT4_MOUNT2_DAX_NEVER;
2397                 sbi->s_mount_opt &= ~EXT4_MOUNT_DAX_ALWAYS;
2398                 return -1;
2399 #endif
2400         } else if (token == Opt_data_err_abort) {
2401                 sbi->s_mount_opt |= m->mount_opt;
2402         } else if (token == Opt_data_err_ignore) {
2403                 sbi->s_mount_opt &= ~m->mount_opt;
2404         } else {
2405                 if (!args->from)
2406                         arg = 1;
2407                 if (m->flags & MOPT_CLEAR)
2408                         arg = !arg;
2409                 else if (unlikely(!(m->flags & MOPT_SET))) {
2410                         ext4_msg(sb, KERN_WARNING,
2411                                  "buggy handling of option %s", opt);
2412                         WARN_ON(1);
2413                         return -1;
2414                 }
2415                 if (m->flags & MOPT_2) {
2416                         if (arg != 0)
2417                                 sbi->s_mount_opt2 |= m->mount_opt;
2418                         else
2419                                 sbi->s_mount_opt2 &= ~m->mount_opt;
2420                 } else {
2421                         if (arg != 0)
2422                                 sbi->s_mount_opt |= m->mount_opt;
2423                         else
2424                                 sbi->s_mount_opt &= ~m->mount_opt;
2425                 }
2426         }
2427         return 1;
2428 }
2429
2430 static int parse_options(char *options, struct super_block *sb,
2431                          unsigned long *journal_devnum,
2432                          unsigned int *journal_ioprio,
2433                          int is_remount)
2434 {
2435         struct ext4_sb_info __maybe_unused *sbi = EXT4_SB(sb);
2436         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
2437         substring_t args[MAX_OPT_ARGS];
2438         int token;
2439
2440         if (!options)
2441                 return 1;
2442
2443         while ((p = strsep(&options, ",")) != NULL) {
2444                 if (!*p)
2445                         continue;
2446                 /*
2447                  * Initialize args struct so we know whether arg was
2448                  * found; some options take optional arguments.
2449                  */
2450                 args[0].to = args[0].from = NULL;
2451                 token = match_token(p, tokens, args);
2452                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
2453                                      journal_ioprio, is_remount) < 0)
2454                         return 0;
2455         }
2456 #ifdef CONFIG_QUOTA
2457         /*
2458          * We do the test below only for project quotas. 'usrquota' and
2459          * 'grpquota' mount options are allowed even without quota feature
2460          * to support legacy quotas in quota files.
2461          */
2462         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2463                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2464                          "Cannot enable project quota enforcement.");
2465                 return 0;
2466         }
2467         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2468         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2469         if (usr_qf_name || grp_qf_name) {
2470                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2471                         clear_opt(sb, USRQUOTA);
2472
2473                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2474                         clear_opt(sb, GRPQUOTA);
2475
2476                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2477                         ext4_msg(sb, KERN_ERR, "old and new quota "
2478                                         "format mixing");
2479                         return 0;
2480                 }
2481
2482                 if (!sbi->s_jquota_fmt) {
2483                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2484                                         "not specified");
2485                         return 0;
2486                 }
2487         }
2488 #endif
2489         if (test_opt(sb, DIOREAD_NOLOCK)) {
2490                 int blocksize =
2491                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2492                 if (blocksize < PAGE_SIZE)
2493                         ext4_msg(sb, KERN_WARNING, "Warning: mounting with an "
2494                                  "experimental mount option 'dioread_nolock' "
2495                                  "for blocksize < PAGE_SIZE");
2496         }
2497         return 1;
2498 }
2499
2500 static inline void ext4_show_quota_options(struct seq_file *seq,
2501                                            struct super_block *sb)
2502 {
2503 #if defined(CONFIG_QUOTA)
2504         struct ext4_sb_info *sbi = EXT4_SB(sb);
2505         char *usr_qf_name, *grp_qf_name;
2506
2507         if (sbi->s_jquota_fmt) {
2508                 char *fmtname = "";
2509
2510                 switch (sbi->s_jquota_fmt) {
2511                 case QFMT_VFS_OLD:
2512                         fmtname = "vfsold";
2513                         break;
2514                 case QFMT_VFS_V0:
2515                         fmtname = "vfsv0";
2516                         break;
2517                 case QFMT_VFS_V1:
2518                         fmtname = "vfsv1";
2519                         break;
2520                 }
2521                 seq_printf(seq, ",jqfmt=%s", fmtname);
2522         }
2523
2524         rcu_read_lock();
2525         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2526         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2527         if (usr_qf_name)
2528                 seq_show_option(seq, "usrjquota", usr_qf_name);
2529         if (grp_qf_name)
2530                 seq_show_option(seq, "grpjquota", grp_qf_name);
2531         rcu_read_unlock();
2532 #endif
2533 }
2534
2535 static const char *token2str(int token)
2536 {
2537         const struct match_token *t;
2538
2539         for (t = tokens; t->token != Opt_err; t++)
2540                 if (t->token == token && !strchr(t->pattern, '='))
2541                         break;
2542         return t->pattern;
2543 }
2544
2545 /*
2546  * Show an option if
2547  *  - it's set to a non-default value OR
2548  *  - if the per-sb default is different from the global default
2549  */
2550 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2551                               int nodefs)
2552 {
2553         struct ext4_sb_info *sbi = EXT4_SB(sb);
2554         struct ext4_super_block *es = sbi->s_es;
2555         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2556         const struct mount_opts *m;
2557         char sep = nodefs ? '\n' : ',';
2558
2559 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2560 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2561
2562         if (sbi->s_sb_block != 1)
2563                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2564
2565         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2566                 int want_set = m->flags & MOPT_SET;
2567                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2568                     (m->flags & MOPT_CLEAR_ERR) || m->flags & MOPT_SKIP)
2569                         continue;
2570                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2571                         continue; /* skip if same as the default */
2572                 if ((want_set &&
2573                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2574                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2575                         continue; /* select Opt_noFoo vs Opt_Foo */
2576                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2577         }
2578
2579         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2580             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2581                 SEQ_OPTS_PRINT("resuid=%u",
2582                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2583         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2584             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2585                 SEQ_OPTS_PRINT("resgid=%u",
2586                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2587         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2588         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2589                 SEQ_OPTS_PUTS("errors=remount-ro");
2590         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2591                 SEQ_OPTS_PUTS("errors=continue");
2592         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2593                 SEQ_OPTS_PUTS("errors=panic");
2594         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2595                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2596         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2597                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2598         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2599                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2600         if (sb->s_flags & SB_I_VERSION)
2601                 SEQ_OPTS_PUTS("i_version");
2602         if (nodefs || sbi->s_stripe)
2603                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2604         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2605                         (sbi->s_mount_opt ^ def_mount_opt)) {
2606                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2607                         SEQ_OPTS_PUTS("data=journal");
2608                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2609                         SEQ_OPTS_PUTS("data=ordered");
2610                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2611                         SEQ_OPTS_PUTS("data=writeback");
2612         }
2613         if (nodefs ||
2614             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2615                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2616                                sbi->s_inode_readahead_blks);
2617
2618         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2619                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2620                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2621         if (nodefs || sbi->s_max_dir_size_kb)
2622                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2623         if (test_opt(sb, DATA_ERR_ABORT))
2624                 SEQ_OPTS_PUTS("data_err=abort");
2625
2626         fscrypt_show_test_dummy_encryption(seq, sep, sb);
2627
2628         if (sb->s_flags & SB_INLINECRYPT)
2629                 SEQ_OPTS_PUTS("inlinecrypt");
2630
2631         if (test_opt(sb, DAX_ALWAYS)) {
2632                 if (IS_EXT2_SB(sb))
2633                         SEQ_OPTS_PUTS("dax");
2634                 else
2635                         SEQ_OPTS_PUTS("dax=always");
2636         } else if (test_opt2(sb, DAX_NEVER)) {
2637                 SEQ_OPTS_PUTS("dax=never");
2638         } else if (test_opt2(sb, DAX_INODE)) {
2639                 SEQ_OPTS_PUTS("dax=inode");
2640         }
2641         ext4_show_quota_options(seq, sb);
2642         return 0;
2643 }
2644
2645 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2646 {
2647         return _ext4_show_options(seq, root->d_sb, 0);
2648 }
2649
2650 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2651 {
2652         struct super_block *sb = seq->private;
2653         int rc;
2654
2655         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2656         rc = _ext4_show_options(seq, sb, 1);
2657         seq_puts(seq, "\n");
2658         return rc;
2659 }
2660
2661 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2662                             int read_only)
2663 {
2664         struct ext4_sb_info *sbi = EXT4_SB(sb);
2665         int err = 0;
2666
2667         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2668                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2669                          "forcing read-only mode");
2670                 err = -EROFS;
2671                 goto done;
2672         }
2673         if (read_only)
2674                 goto done;
2675         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2676                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2677                          "running e2fsck is recommended");
2678         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2679                 ext4_msg(sb, KERN_WARNING,
2680                          "warning: mounting fs with errors, "
2681                          "running e2fsck is recommended");
2682         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2683                  le16_to_cpu(es->s_mnt_count) >=
2684                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2685                 ext4_msg(sb, KERN_WARNING,
2686                          "warning: maximal mount count reached, "
2687                          "running e2fsck is recommended");
2688         else if (le32_to_cpu(es->s_checkinterval) &&
2689                  (ext4_get_tstamp(es, s_lastcheck) +
2690                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2691                 ext4_msg(sb, KERN_WARNING,
2692                          "warning: checktime reached, "
2693                          "running e2fsck is recommended");
2694         if (!sbi->s_journal)
2695                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2696         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2697                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2698         le16_add_cpu(&es->s_mnt_count, 1);
2699         ext4_update_tstamp(es, s_mtime);
2700         if (sbi->s_journal)
2701                 ext4_set_feature_journal_needs_recovery(sb);
2702
2703         err = ext4_commit_super(sb, 1);
2704 done:
2705         if (test_opt(sb, DEBUG))
2706                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2707                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2708                         sb->s_blocksize,
2709                         sbi->s_groups_count,
2710                         EXT4_BLOCKS_PER_GROUP(sb),
2711                         EXT4_INODES_PER_GROUP(sb),
2712                         sbi->s_mount_opt, sbi->s_mount_opt2);
2713
2714         cleancache_init_fs(sb);
2715         return err;
2716 }
2717
2718 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2719 {
2720         struct ext4_sb_info *sbi = EXT4_SB(sb);
2721         struct flex_groups **old_groups, **new_groups;
2722         int size, i, j;
2723
2724         if (!sbi->s_log_groups_per_flex)
2725                 return 0;
2726
2727         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2728         if (size <= sbi->s_flex_groups_allocated)
2729                 return 0;
2730
2731         new_groups = kvzalloc(roundup_pow_of_two(size *
2732                               sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2733         if (!new_groups) {
2734                 ext4_msg(sb, KERN_ERR,
2735                          "not enough memory for %d flex group pointers", size);
2736                 return -ENOMEM;
2737         }
2738         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2739                 new_groups[i] = kvzalloc(roundup_pow_of_two(
2740                                          sizeof(struct flex_groups)),
2741                                          GFP_KERNEL);
2742                 if (!new_groups[i]) {
2743                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2744                                 kvfree(new_groups[j]);
2745                         kvfree(new_groups);
2746                         ext4_msg(sb, KERN_ERR,
2747                                  "not enough memory for %d flex groups", size);
2748                         return -ENOMEM;
2749                 }
2750         }
2751         rcu_read_lock();
2752         old_groups = rcu_dereference(sbi->s_flex_groups);
2753         if (old_groups)
2754                 memcpy(new_groups, old_groups,
2755                        (sbi->s_flex_groups_allocated *
2756                         sizeof(struct flex_groups *)));
2757         rcu_read_unlock();
2758         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2759         sbi->s_flex_groups_allocated = size;
2760         if (old_groups)
2761                 ext4_kvfree_array_rcu(old_groups);
2762         return 0;
2763 }
2764
2765 static int ext4_fill_flex_info(struct super_block *sb)
2766 {
2767         struct ext4_sb_info *sbi = EXT4_SB(sb);
2768         struct ext4_group_desc *gdp = NULL;
2769         struct flex_groups *fg;
2770         ext4_group_t flex_group;
2771         int i, err;
2772
2773         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2774         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2775                 sbi->s_log_groups_per_flex = 0;
2776                 return 1;
2777         }
2778
2779         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2780         if (err)
2781                 goto failed;
2782
2783         for (i = 0; i < sbi->s_groups_count; i++) {
2784                 gdp = ext4_get_group_desc(sb, i, NULL);
2785
2786                 flex_group = ext4_flex_group(sbi, i);
2787                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2788                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2789                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2790                              &fg->free_clusters);
2791                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2792         }
2793
2794         return 1;
2795 failed:
2796         return 0;
2797 }
2798
2799 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2800                                    struct ext4_group_desc *gdp)
2801 {
2802         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2803         __u16 crc = 0;
2804         __le32 le_group = cpu_to_le32(block_group);
2805         struct ext4_sb_info *sbi = EXT4_SB(sb);
2806
2807         if (ext4_has_metadata_csum(sbi->s_sb)) {
2808                 /* Use new metadata_csum algorithm */
2809                 __u32 csum32;
2810                 __u16 dummy_csum = 0;
2811
2812                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2813                                      sizeof(le_group));
2814                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2815                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2816                                      sizeof(dummy_csum));
2817                 offset += sizeof(dummy_csum);
2818                 if (offset < sbi->s_desc_size)
2819                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2820                                              sbi->s_desc_size - offset);
2821
2822                 crc = csum32 & 0xFFFF;
2823                 goto out;
2824         }
2825
2826         /* old crc16 code */
2827         if (!ext4_has_feature_gdt_csum(sb))
2828                 return 0;
2829
2830         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2831         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2832         crc = crc16(crc, (__u8 *)gdp, offset);
2833         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2834         /* for checksum of struct ext4_group_desc do the rest...*/
2835         if (ext4_has_feature_64bit(sb) &&
2836             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2837                 crc = crc16(crc, (__u8 *)gdp + offset,
2838                             le16_to_cpu(sbi->s_es->s_desc_size) -
2839                                 offset);
2840
2841 out:
2842         return cpu_to_le16(crc);
2843 }
2844
2845 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2846                                 struct ext4_group_desc *gdp)
2847 {
2848         if (ext4_has_group_desc_csum(sb) &&
2849             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2850                 return 0;
2851
2852         return 1;
2853 }
2854
2855 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2856                               struct ext4_group_desc *gdp)
2857 {
2858         if (!ext4_has_group_desc_csum(sb))
2859                 return;
2860         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2861 }
2862
2863 /* Called at mount-time, super-block is locked */
2864 static int ext4_check_descriptors(struct super_block *sb,
2865                                   ext4_fsblk_t sb_block,
2866                                   ext4_group_t *first_not_zeroed)
2867 {
2868         struct ext4_sb_info *sbi = EXT4_SB(sb);
2869         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2870         ext4_fsblk_t last_block;
2871         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2872         ext4_fsblk_t block_bitmap;
2873         ext4_fsblk_t inode_bitmap;
2874         ext4_fsblk_t inode_table;
2875         int flexbg_flag = 0;
2876         ext4_group_t i, grp = sbi->s_groups_count;
2877
2878         if (ext4_has_feature_flex_bg(sb))
2879                 flexbg_flag = 1;
2880
2881         ext4_debug("Checking group descriptors");
2882
2883         for (i = 0; i < sbi->s_groups_count; i++) {
2884                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2885
2886                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2887                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2888                 else
2889                         last_block = first_block +
2890                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2891
2892                 if ((grp == sbi->s_groups_count) &&
2893                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2894                         grp = i;
2895
2896                 block_bitmap = ext4_block_bitmap(sb, gdp);
2897                 if (block_bitmap == sb_block) {
2898                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2899                                  "Block bitmap for group %u overlaps "
2900                                  "superblock", i);
2901                         if (!sb_rdonly(sb))
2902                                 return 0;
2903                 }
2904                 if (block_bitmap >= sb_block + 1 &&
2905                     block_bitmap <= last_bg_block) {
2906                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2907                                  "Block bitmap for group %u overlaps "
2908                                  "block group descriptors", i);
2909                         if (!sb_rdonly(sb))
2910                                 return 0;
2911                 }
2912                 if (block_bitmap < first_block || block_bitmap > last_block) {
2913                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2914                                "Block bitmap for group %u not in group "
2915                                "(block %llu)!", i, block_bitmap);
2916                         return 0;
2917                 }
2918                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2919                 if (inode_bitmap == sb_block) {
2920                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2921                                  "Inode bitmap for group %u overlaps "
2922                                  "superblock", i);
2923                         if (!sb_rdonly(sb))
2924                                 return 0;
2925                 }
2926                 if (inode_bitmap >= sb_block + 1 &&
2927                     inode_bitmap <= last_bg_block) {
2928                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2929                                  "Inode bitmap for group %u overlaps "
2930                                  "block group descriptors", i);
2931                         if (!sb_rdonly(sb))
2932                                 return 0;
2933                 }
2934                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2935                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2936                                "Inode bitmap for group %u not in group "
2937                                "(block %llu)!", i, inode_bitmap);
2938                         return 0;
2939                 }
2940                 inode_table = ext4_inode_table(sb, gdp);
2941                 if (inode_table == sb_block) {
2942                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2943                                  "Inode table for group %u overlaps "
2944                                  "superblock", i);
2945                         if (!sb_rdonly(sb))
2946                                 return 0;
2947                 }
2948                 if (inode_table >= sb_block + 1 &&
2949                     inode_table <= last_bg_block) {
2950                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2951                                  "Inode table for group %u overlaps "
2952                                  "block group descriptors", i);
2953                         if (!sb_rdonly(sb))
2954                                 return 0;
2955                 }
2956                 if (inode_table < first_block ||
2957                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2958                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2959                                "Inode table for group %u not in group "
2960                                "(block %llu)!", i, inode_table);
2961                         return 0;
2962                 }
2963                 ext4_lock_group(sb, i);
2964                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2965                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2966                                  "Checksum for group %u failed (%u!=%u)",
2967                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2968                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2969                         if (!sb_rdonly(sb)) {
2970                                 ext4_unlock_group(sb, i);
2971                                 return 0;
2972                         }
2973                 }
2974                 ext4_unlock_group(sb, i);
2975                 if (!flexbg_flag)
2976                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2977         }
2978         if (NULL != first_not_zeroed)
2979                 *first_not_zeroed = grp;
2980         return 1;
2981 }
2982
2983 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2984  * the superblock) which were deleted from all directories, but held open by
2985  * a process at the time of a crash.  We walk the list and try to delete these
2986  * inodes at recovery time (only with a read-write filesystem).
2987  *
2988  * In order to keep the orphan inode chain consistent during traversal (in
2989  * case of crash during recovery), we link each inode into the superblock
2990  * orphan list_head and handle it the same way as an inode deletion during
2991  * normal operation (which journals the operations for us).
2992  *
2993  * We only do an iget() and an iput() on each inode, which is very safe if we
2994  * accidentally point at an in-use or already deleted inode.  The worst that
2995  * can happen in this case is that we get a "bit already cleared" message from
2996  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2997  * e2fsck was run on this filesystem, and it must have already done the orphan
2998  * inode cleanup for us, so we can safely abort without any further action.
2999  */
3000 static void ext4_orphan_cleanup(struct super_block *sb,
3001                                 struct ext4_super_block *es)
3002 {
3003         unsigned int s_flags = sb->s_flags;
3004         int ret, nr_orphans = 0, nr_truncates = 0;
3005 #ifdef CONFIG_QUOTA
3006         int quota_update = 0;
3007         int i;
3008 #endif
3009         if (!es->s_last_orphan) {
3010                 jbd_debug(4, "no orphan inodes to clean up\n");
3011                 return;
3012         }
3013
3014         if (bdev_read_only(sb->s_bdev)) {
3015                 ext4_msg(sb, KERN_ERR, "write access "
3016                         "unavailable, skipping orphan cleanup");
3017                 return;
3018         }
3019
3020         /* Check if feature set would not allow a r/w mount */
3021         if (!ext4_feature_set_ok(sb, 0)) {
3022                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
3023                          "unknown ROCOMPAT features");
3024                 return;
3025         }
3026
3027         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3028                 /* don't clear list on RO mount w/ errors */
3029                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
3030                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
3031                                   "clearing orphan list.\n");
3032                         es->s_last_orphan = 0;
3033                 }
3034                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3035                 return;
3036         }
3037
3038         if (s_flags & SB_RDONLY) {
3039                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
3040                 sb->s_flags &= ~SB_RDONLY;
3041         }
3042 #ifdef CONFIG_QUOTA
3043         /* Needed for iput() to work correctly and not trash data */
3044         sb->s_flags |= SB_ACTIVE;
3045
3046         /*
3047          * Turn on quotas which were not enabled for read-only mounts if
3048          * filesystem has quota feature, so that they are updated correctly.
3049          */
3050         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
3051                 int ret = ext4_enable_quotas(sb);
3052
3053                 if (!ret)
3054                         quota_update = 1;
3055                 else
3056                         ext4_msg(sb, KERN_ERR,
3057                                 "Cannot turn on quotas: error %d", ret);
3058         }
3059
3060         /* Turn on journaled quotas used for old sytle */
3061         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3062                 if (EXT4_SB(sb)->s_qf_names[i]) {
3063                         int ret = ext4_quota_on_mount(sb, i);
3064
3065                         if (!ret)
3066                                 quota_update = 1;
3067                         else
3068                                 ext4_msg(sb, KERN_ERR,
3069                                         "Cannot turn on journaled "
3070                                         "quota: type %d: error %d", i, ret);
3071                 }
3072         }
3073 #endif
3074
3075         while (es->s_last_orphan) {
3076                 struct inode *inode;
3077
3078                 /*
3079                  * We may have encountered an error during cleanup; if
3080                  * so, skip the rest.
3081                  */
3082                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
3083                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
3084                         es->s_last_orphan = 0;
3085                         break;
3086                 }
3087
3088                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
3089                 if (IS_ERR(inode)) {
3090                         es->s_last_orphan = 0;
3091                         break;
3092                 }
3093
3094                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
3095                 dquot_initialize(inode);
3096                 if (inode->i_nlink) {
3097                         if (test_opt(sb, DEBUG))
3098                                 ext4_msg(sb, KERN_DEBUG,
3099                                         "%s: truncating inode %lu to %lld bytes",
3100                                         __func__, inode->i_ino, inode->i_size);
3101                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
3102                                   inode->i_ino, inode->i_size);
3103                         inode_lock(inode);
3104                         truncate_inode_pages(inode->i_mapping, inode->i_size);
3105                         ret = ext4_truncate(inode);
3106                         if (ret)
3107                                 ext4_std_error(inode->i_sb, ret);
3108                         inode_unlock(inode);
3109                         nr_truncates++;
3110                 } else {
3111                         if (test_opt(sb, DEBUG))
3112                                 ext4_msg(sb, KERN_DEBUG,
3113                                         "%s: deleting unreferenced inode %lu",
3114                                         __func__, inode->i_ino);
3115                         jbd_debug(2, "deleting unreferenced inode %lu\n",
3116                                   inode->i_ino);
3117                         nr_orphans++;
3118                 }
3119                 iput(inode);  /* The delete magic happens here! */
3120         }
3121
3122 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
3123
3124         if (nr_orphans)
3125                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
3126                        PLURAL(nr_orphans));
3127         if (nr_truncates)
3128                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
3129                        PLURAL(nr_truncates));
3130 #ifdef CONFIG_QUOTA
3131         /* Turn off quotas if they were enabled for orphan cleanup */
3132         if (quota_update) {
3133                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
3134                         if (sb_dqopt(sb)->files[i])
3135                                 dquot_quota_off(sb, i);
3136                 }
3137         }
3138 #endif
3139         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
3140 }
3141
3142 /*
3143  * Maximal extent format file size.
3144  * Resulting logical blkno at s_maxbytes must fit in our on-disk
3145  * extent format containers, within a sector_t, and within i_blocks
3146  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
3147  * so that won't be a limiting factor.
3148  *
3149  * However there is other limiting factor. We do store extents in the form
3150  * of starting block and length, hence the resulting length of the extent
3151  * covering maximum file size must fit into on-disk format containers as
3152  * well. Given that length is always by 1 unit bigger than max unit (because
3153  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
3154  *
3155  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
3156  */
3157 static loff_t ext4_max_size(int blkbits, int has_huge_files)
3158 {
3159         loff_t res;
3160         loff_t upper_limit = MAX_LFS_FILESIZE;
3161
3162         BUILD_BUG_ON(sizeof(blkcnt_t) < sizeof(u64));
3163
3164         if (!has_huge_files) {
3165                 upper_limit = (1LL << 32) - 1;
3166
3167                 /* total blocks in file system block size */
3168                 upper_limit >>= (blkbits - 9);
3169                 upper_limit <<= blkbits;
3170         }
3171
3172         /*
3173          * 32-bit extent-start container, ee_block. We lower the maxbytes
3174          * by one fs block, so ee_len can cover the extent of maximum file
3175          * size
3176          */
3177         res = (1LL << 32) - 1;
3178         res <<= blkbits;
3179
3180         /* Sanity check against vm- & vfs- imposed limits */
3181         if (res > upper_limit)
3182                 res = upper_limit;
3183
3184         return res;
3185 }
3186
3187 /*
3188  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
3189  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
3190  * We need to be 1 filesystem block less than the 2^48 sector limit.
3191  */
3192 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
3193 {
3194         loff_t res = EXT4_NDIR_BLOCKS;
3195         int meta_blocks;
3196         loff_t upper_limit;
3197         /* This is calculated to be the largest file size for a dense, block
3198          * mapped file such that the file's total number of 512-byte sectors,
3199          * including data and all indirect blocks, does not exceed (2^48 - 1).
3200          *
3201          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
3202          * number of 512-byte sectors of the file.
3203          */
3204
3205         if (!has_huge_files) {
3206                 /*
3207                  * !has_huge_files or implies that the inode i_block field
3208                  * represents total file blocks in 2^32 512-byte sectors ==
3209                  * size of vfs inode i_blocks * 8
3210                  */
3211                 upper_limit = (1LL << 32) - 1;
3212
3213                 /* total blocks in file system block size */
3214                 upper_limit >>= (bits - 9);
3215
3216         } else {
3217                 /*
3218                  * We use 48 bit ext4_inode i_blocks
3219                  * With EXT4_HUGE_FILE_FL set the i_blocks
3220                  * represent total number of blocks in
3221                  * file system block size
3222                  */
3223                 upper_limit = (1LL << 48) - 1;
3224
3225         }
3226
3227         /* indirect blocks */
3228         meta_blocks = 1;
3229         /* double indirect blocks */
3230         meta_blocks += 1 + (1LL << (bits-2));
3231         /* tripple indirect blocks */
3232         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
3233
3234         upper_limit -= meta_blocks;
3235         upper_limit <<= bits;
3236
3237         res += 1LL << (bits-2);
3238         res += 1LL << (2*(bits-2));
3239         res += 1LL << (3*(bits-2));
3240         res <<= bits;
3241         if (res > upper_limit)
3242                 res = upper_limit;
3243
3244         if (res > MAX_LFS_FILESIZE)
3245                 res = MAX_LFS_FILESIZE;
3246
3247         return res;
3248 }
3249
3250 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
3251                                    ext4_fsblk_t logical_sb_block, int nr)
3252 {
3253         struct ext4_sb_info *sbi = EXT4_SB(sb);
3254         ext4_group_t bg, first_meta_bg;
3255         int has_super = 0;
3256
3257         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
3258
3259         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
3260                 return logical_sb_block + nr + 1;
3261         bg = sbi->s_desc_per_block * nr;
3262         if (ext4_bg_has_super(sb, bg))
3263                 has_super = 1;
3264
3265         /*
3266          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
3267          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
3268          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
3269          * compensate.
3270          */
3271         if (sb->s_blocksize == 1024 && nr == 0 &&
3272             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
3273                 has_super++;
3274
3275         return (has_super + ext4_group_first_block_no(sb, bg));
3276 }
3277
3278 /**
3279  * ext4_get_stripe_size: Get the stripe size.
3280  * @sbi: In memory super block info
3281  *
3282  * If we have specified it via mount option, then
3283  * use the mount option value. If the value specified at mount time is
3284  * greater than the blocks per group use the super block value.
3285  * If the super block value is greater than blocks per group return 0.
3286  * Allocator needs it be less than blocks per group.
3287  *
3288  */
3289 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
3290 {
3291         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
3292         unsigned long stripe_width =
3293                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
3294         int ret;
3295
3296         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
3297                 ret = sbi->s_stripe;
3298         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
3299                 ret = stripe_width;
3300         else if (stride && stride <= sbi->s_blocks_per_group)
3301                 ret = stride;
3302         else
3303                 ret = 0;
3304
3305         /*
3306          * If the stripe width is 1, this makes no sense and
3307          * we set it to 0 to turn off stripe handling code.
3308          */
3309         if (ret <= 1)
3310                 ret = 0;
3311
3312         return ret;
3313 }
3314
3315 /*
3316  * Check whether this filesystem can be mounted based on
3317  * the features present and the RDONLY/RDWR mount requested.
3318  * Returns 1 if this filesystem can be mounted as requested,
3319  * 0 if it cannot be.
3320  */
3321 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
3322 {
3323         if (ext4_has_unknown_ext4_incompat_features(sb)) {
3324                 ext4_msg(sb, KERN_ERR,
3325                         "Couldn't mount because of "
3326                         "unsupported optional features (%x)",
3327                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
3328                         ~EXT4_FEATURE_INCOMPAT_SUPP));
3329                 return 0;
3330         }
3331
3332 #ifndef CONFIG_UNICODE
3333         if (ext4_has_feature_casefold(sb)) {
3334                 ext4_msg(sb, KERN_ERR,
3335                          "Filesystem with casefold feature cannot be "
3336                          "mounted without CONFIG_UNICODE");
3337                 return 0;
3338         }
3339 #endif
3340
3341         if (readonly)
3342                 return 1;
3343
3344         if (ext4_has_feature_readonly(sb)) {
3345                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
3346                 sb->s_flags |= SB_RDONLY;
3347                 return 1;
3348         }
3349
3350         /* Check that feature set is OK for a read-write mount */
3351         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
3352                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
3353                          "unsupported optional features (%x)",
3354                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
3355                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
3356                 return 0;
3357         }
3358         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
3359                 ext4_msg(sb, KERN_ERR,
3360                          "Can't support bigalloc feature without "
3361                          "extents feature\n");
3362                 return 0;
3363         }
3364
3365 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
3366         if (!readonly && (ext4_has_feature_quota(sb) ||
3367                           ext4_has_feature_project(sb))) {
3368                 ext4_msg(sb, KERN_ERR,
3369                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
3370                 return 0;
3371         }
3372 #endif  /* CONFIG_QUOTA */
3373         return 1;
3374 }
3375
3376 /*
3377  * This function is called once a day if we have errors logged
3378  * on the file system
3379  */
3380 static void print_daily_error_info(struct timer_list *t)
3381 {
3382         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
3383         struct super_block *sb = sbi->s_sb;
3384         struct ext4_super_block *es = sbi->s_es;
3385
3386         if (es->s_error_count)
3387                 /* fsck newer than v1.41.13 is needed to clean this condition. */
3388                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
3389                          le32_to_cpu(es->s_error_count));
3390         if (es->s_first_error_time) {
3391                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
3392                        sb->s_id,
3393                        ext4_get_tstamp(es, s_first_error_time),
3394                        (int) sizeof(es->s_first_error_func),
3395                        es->s_first_error_func,
3396                        le32_to_cpu(es->s_first_error_line));
3397                 if (es->s_first_error_ino)
3398                         printk(KERN_CONT ": inode %u",
3399                                le32_to_cpu(es->s_first_error_ino));
3400                 if (es->s_first_error_block)
3401                         printk(KERN_CONT ": block %llu", (unsigned long long)
3402                                le64_to_cpu(es->s_first_error_block));
3403                 printk(KERN_CONT "\n");
3404         }
3405         if (es->s_last_error_time) {
3406                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
3407                        sb->s_id,
3408                        ext4_get_tstamp(es, s_last_error_time),
3409                        (int) sizeof(es->s_last_error_func),
3410                        es->s_last_error_func,
3411                        le32_to_cpu(es->s_last_error_line));
3412                 if (es->s_last_error_ino)
3413                         printk(KERN_CONT ": inode %u",
3414                                le32_to_cpu(es->s_last_error_ino));
3415                 if (es->s_last_error_block)
3416                         printk(KERN_CONT ": block %llu", (unsigned long long)
3417                                le64_to_cpu(es->s_last_error_block));
3418                 printk(KERN_CONT "\n");
3419         }
3420         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
3421 }
3422
3423 /* Find next suitable group and run ext4_init_inode_table */
3424 static int ext4_run_li_request(struct ext4_li_request *elr)
3425 {
3426         struct ext4_group_desc *gdp = NULL;
3427         struct super_block *sb = elr->lr_super;
3428         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3429         ext4_group_t group = elr->lr_next_group;
3430         unsigned long timeout = 0;
3431         unsigned int prefetch_ios = 0;
3432         int ret = 0;
3433
3434         if (elr->lr_mode == EXT4_LI_MODE_PREFETCH_BBITMAP) {
3435                 elr->lr_next_group = ext4_mb_prefetch(sb, group,
3436                                 EXT4_SB(sb)->s_mb_prefetch, &prefetch_ios);
3437                 if (prefetch_ios)
3438                         ext4_mb_prefetch_fini(sb, elr->lr_next_group,
3439                                               prefetch_ios);
3440                 trace_ext4_prefetch_bitmaps(sb, group, elr->lr_next_group,
3441                                             prefetch_ios);
3442                 if (group >= elr->lr_next_group) {
3443                         ret = 1;
3444                         if (elr->lr_first_not_zeroed != ngroups &&
3445                             !sb_rdonly(sb) && test_opt(sb, INIT_INODE_TABLE)) {
3446                                 elr->lr_next_group = elr->lr_first_not_zeroed;
3447                                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3448                                 ret = 0;
3449                         }
3450                 }
3451                 return ret;
3452         }
3453
3454         for (; group < ngroups; group++) {
3455                 gdp = ext4_get_group_desc(sb, group, NULL);
3456                 if (!gdp) {
3457                         ret = 1;
3458                         break;
3459                 }
3460
3461                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3462                         break;
3463         }
3464
3465         if (group >= ngroups)
3466                 ret = 1;
3467
3468         if (!ret) {
3469                 timeout = jiffies;
3470                 ret = ext4_init_inode_table(sb, group,
3471                                             elr->lr_timeout ? 0 : 1);
3472                 trace_ext4_lazy_itable_init(sb, group);
3473                 if (elr->lr_timeout == 0) {
3474                         timeout = (jiffies - timeout) *
3475                                 EXT4_SB(elr->lr_super)->s_li_wait_mult;
3476                         elr->lr_timeout = timeout;
3477                 }
3478                 elr->lr_next_sched = jiffies + elr->lr_timeout;
3479                 elr->lr_next_group = group + 1;
3480         }
3481         return ret;
3482 }
3483
3484 /*
3485  * Remove lr_request from the list_request and free the
3486  * request structure. Should be called with li_list_mtx held
3487  */
3488 static void ext4_remove_li_request(struct ext4_li_request *elr)
3489 {
3490         if (!elr)
3491                 return;
3492
3493         list_del(&elr->lr_request);
3494         EXT4_SB(elr->lr_super)->s_li_request = NULL;
3495         kfree(elr);
3496 }
3497
3498 static void ext4_unregister_li_request(struct super_block *sb)
3499 {
3500         mutex_lock(&ext4_li_mtx);
3501         if (!ext4_li_info) {
3502                 mutex_unlock(&ext4_li_mtx);
3503                 return;
3504         }
3505
3506         mutex_lock(&ext4_li_info->li_list_mtx);
3507         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3508         mutex_unlock(&ext4_li_info->li_list_mtx);
3509         mutex_unlock(&ext4_li_mtx);
3510 }
3511
3512 static struct task_struct *ext4_lazyinit_task;
3513
3514 /*
3515  * This is the function where ext4lazyinit thread lives. It walks
3516  * through the request list searching for next scheduled filesystem.
3517  * When such a fs is found, run the lazy initialization request
3518  * (ext4_rn_li_request) and keep track of the time spend in this
3519  * function. Based on that time we compute next schedule time of
3520  * the request. When walking through the list is complete, compute
3521  * next waking time and put itself into sleep.
3522  */
3523 static int ext4_lazyinit_thread(void *arg)
3524 {
3525         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3526         struct list_head *pos, *n;
3527         struct ext4_li_request *elr;
3528         unsigned long next_wakeup, cur;
3529
3530         BUG_ON(NULL == eli);
3531
3532 cont_thread:
3533         while (true) {
3534                 next_wakeup = MAX_JIFFY_OFFSET;
3535
3536                 mutex_lock(&eli->li_list_mtx);
3537                 if (list_empty(&eli->li_request_list)) {
3538                         mutex_unlock(&eli->li_list_mtx);
3539                         goto exit_thread;
3540                 }
3541                 list_for_each_safe(pos, n, &eli->li_request_list) {
3542                         int err = 0;
3543                         int progress = 0;
3544                         elr = list_entry(pos, struct ext4_li_request,
3545                                          lr_request);
3546
3547                         if (time_before(jiffies, elr->lr_next_sched)) {
3548                                 if (time_before(elr->lr_next_sched, next_wakeup))
3549                                         next_wakeup = elr->lr_next_sched;
3550                                 continue;
3551                         }
3552                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3553                                 if (sb_start_write_trylock(elr->lr_super)) {
3554                                         progress = 1;
3555                                         /*
3556                                          * We hold sb->s_umount, sb can not
3557                                          * be removed from the list, it is
3558                                          * now safe to drop li_list_mtx
3559                                          */
3560                                         mutex_unlock(&eli->li_list_mtx);
3561                                         err = ext4_run_li_request(elr);
3562                                         sb_end_write(elr->lr_super);
3563                                         mutex_lock(&eli->li_list_mtx);
3564                                         n = pos->next;
3565                                 }
3566                                 up_read((&elr->lr_super->s_umount));
3567                         }
3568                         /* error, remove the lazy_init job */
3569                         if (err) {
3570                                 ext4_remove_li_request(elr);
3571                                 continue;
3572                         }
3573                         if (!progress) {
3574                                 elr->lr_next_sched = jiffies +
3575                                         (prandom_u32()
3576                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3577                         }
3578                         if (time_before(elr->lr_next_sched, next_wakeup))
3579                                 next_wakeup = elr->lr_next_sched;
3580                 }
3581                 mutex_unlock(&eli->li_list_mtx);
3582
3583                 try_to_freeze();
3584
3585                 cur = jiffies;
3586                 if ((time_after_eq(cur, next_wakeup)) ||
3587                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3588                         cond_resched();
3589                         continue;
3590                 }
3591
3592                 schedule_timeout_interruptible(next_wakeup - cur);
3593
3594                 if (kthread_should_stop()) {
3595                         ext4_clear_request_list();
3596                         goto exit_thread;
3597                 }
3598         }
3599
3600 exit_thread:
3601         /*
3602          * It looks like the request list is empty, but we need
3603          * to check it under the li_list_mtx lock, to prevent any
3604          * additions into it, and of course we should lock ext4_li_mtx
3605          * to atomically free the list and ext4_li_info, because at
3606          * this point another ext4 filesystem could be registering
3607          * new one.
3608          */
3609         mutex_lock(&ext4_li_mtx);
3610         mutex_lock(&eli->li_list_mtx);
3611         if (!list_empty(&eli->li_request_list)) {
3612                 mutex_unlock(&eli->li_list_mtx);
3613                 mutex_unlock(&ext4_li_mtx);
3614                 goto cont_thread;
3615         }
3616         mutex_unlock(&eli->li_list_mtx);
3617         kfree(ext4_li_info);
3618         ext4_li_info = NULL;
3619         mutex_unlock(&ext4_li_mtx);
3620
3621         return 0;
3622 }
3623
3624 static void ext4_clear_request_list(void)
3625 {
3626         struct list_head *pos, *n;
3627         struct ext4_li_request *elr;
3628
3629         mutex_lock(&ext4_li_info->li_list_mtx);
3630         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3631                 elr = list_entry(pos, struct ext4_li_request,
3632                                  lr_request);
3633                 ext4_remove_li_request(elr);
3634         }
3635         mutex_unlock(&ext4_li_info->li_list_mtx);
3636 }
3637
3638 static int ext4_run_lazyinit_thread(void)
3639 {
3640         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3641                                          ext4_li_info, "ext4lazyinit");
3642         if (IS_ERR(ext4_lazyinit_task)) {
3643                 int err = PTR_ERR(ext4_lazyinit_task);
3644                 ext4_clear_request_list();
3645                 kfree(ext4_li_info);
3646                 ext4_li_info = NULL;
3647                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3648                                  "initialization thread\n",
3649                                  err);
3650                 return err;
3651         }
3652         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3653         return 0;
3654 }
3655
3656 /*
3657  * Check whether it make sense to run itable init. thread or not.
3658  * If there is at least one uninitialized inode table, return
3659  * corresponding group number, else the loop goes through all
3660  * groups and return total number of groups.
3661  */
3662 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3663 {
3664         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3665         struct ext4_group_desc *gdp = NULL;
3666
3667         if (!ext4_has_group_desc_csum(sb))
3668                 return ngroups;
3669
3670         for (group = 0; group < ngroups; group++) {
3671                 gdp = ext4_get_group_desc(sb, group, NULL);
3672                 if (!gdp)
3673                         continue;
3674
3675                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3676                         break;
3677         }
3678
3679         return group;
3680 }
3681
3682 static int ext4_li_info_new(void)
3683 {
3684         struct ext4_lazy_init *eli = NULL;
3685
3686         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3687         if (!eli)
3688                 return -ENOMEM;
3689
3690         INIT_LIST_HEAD(&eli->li_request_list);
3691         mutex_init(&eli->li_list_mtx);
3692
3693         eli->li_state |= EXT4_LAZYINIT_QUIT;
3694
3695         ext4_li_info = eli;
3696
3697         return 0;
3698 }
3699
3700 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3701                                             ext4_group_t start)
3702 {
3703         struct ext4_li_request *elr;
3704
3705         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3706         if (!elr)
3707                 return NULL;
3708
3709         elr->lr_super = sb;
3710         elr->lr_first_not_zeroed = start;
3711         if (test_opt(sb, PREFETCH_BLOCK_BITMAPS))
3712                 elr->lr_mode = EXT4_LI_MODE_PREFETCH_BBITMAP;
3713         else {
3714                 elr->lr_mode = EXT4_LI_MODE_ITABLE;
3715                 elr->lr_next_group = start;
3716         }
3717
3718         /*
3719          * Randomize first schedule time of the request to
3720          * spread the inode table initialization requests
3721          * better.
3722          */
3723         elr->lr_next_sched = jiffies + (prandom_u32() %
3724                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3725         return elr;
3726 }
3727
3728 int ext4_register_li_request(struct super_block *sb,
3729                              ext4_group_t first_not_zeroed)
3730 {
3731         struct ext4_sb_info *sbi = EXT4_SB(sb);
3732         struct ext4_li_request *elr = NULL;
3733         ext4_group_t ngroups = sbi->s_groups_count;
3734         int ret = 0;
3735
3736         mutex_lock(&ext4_li_mtx);
3737         if (sbi->s_li_request != NULL) {
3738                 /*
3739                  * Reset timeout so it can be computed again, because
3740                  * s_li_wait_mult might have changed.
3741                  */
3742                 sbi->s_li_request->lr_timeout = 0;
3743                 goto out;
3744         }
3745
3746         if (!test_opt(sb, PREFETCH_BLOCK_BITMAPS) &&
3747             (first_not_zeroed == ngroups || sb_rdonly(sb) ||
3748              !test_opt(sb, INIT_INODE_TABLE)))
3749                 goto out;
3750
3751         elr = ext4_li_request_new(sb, first_not_zeroed);
3752         if (!elr) {
3753                 ret = -ENOMEM;
3754                 goto out;
3755         }
3756
3757         if (NULL == ext4_li_info) {
3758                 ret = ext4_li_info_new();
3759                 if (ret)
3760                         goto out;
3761         }
3762
3763         mutex_lock(&ext4_li_info->li_list_mtx);
3764         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3765         mutex_unlock(&ext4_li_info->li_list_mtx);
3766
3767         sbi->s_li_request = elr;
3768         /*
3769          * set elr to NULL here since it has been inserted to
3770          * the request_list and the removal and free of it is
3771          * handled by ext4_clear_request_list from now on.
3772          */
3773         elr = NULL;
3774
3775         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3776                 ret = ext4_run_lazyinit_thread();
3777                 if (ret)
3778                         goto out;
3779         }
3780 out:
3781         mutex_unlock(&ext4_li_mtx);
3782         if (ret)
3783                 kfree(elr);
3784         return ret;
3785 }
3786
3787 /*
3788  * We do not need to lock anything since this is called on
3789  * module unload.
3790  */
3791 static void ext4_destroy_lazyinit_thread(void)
3792 {
3793         /*
3794          * If thread exited earlier
3795          * there's nothing to be done.
3796          */
3797         if (!ext4_li_info || !ext4_lazyinit_task)
3798                 return;
3799
3800         kthread_stop(ext4_lazyinit_task);
3801 }
3802
3803 static int set_journal_csum_feature_set(struct super_block *sb)
3804 {
3805         int ret = 1;
3806         int compat, incompat;
3807         struct ext4_sb_info *sbi = EXT4_SB(sb);
3808
3809         if (ext4_has_metadata_csum(sb)) {
3810                 /* journal checksum v3 */
3811                 compat = 0;
3812                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3813         } else {
3814                 /* journal checksum v1 */
3815                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3816                 incompat = 0;
3817         }
3818
3819         jbd2_journal_clear_features(sbi->s_journal,
3820                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3821                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3822                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3823         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3824                 ret = jbd2_journal_set_features(sbi->s_journal,
3825                                 compat, 0,
3826                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3827                                 incompat);
3828         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3829                 ret = jbd2_journal_set_features(sbi->s_journal,
3830                                 compat, 0,
3831                                 incompat);
3832                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3833                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3834         } else {
3835                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3836                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3837         }
3838
3839         return ret;
3840 }
3841
3842 /*
3843  * Note: calculating the overhead so we can be compatible with
3844  * historical BSD practice is quite difficult in the face of
3845  * clusters/bigalloc.  This is because multiple metadata blocks from
3846  * different block group can end up in the same allocation cluster.
3847  * Calculating the exact overhead in the face of clustered allocation
3848  * requires either O(all block bitmaps) in memory or O(number of block
3849  * groups**2) in time.  We will still calculate the superblock for
3850  * older file systems --- and if we come across with a bigalloc file
3851  * system with zero in s_overhead_clusters the estimate will be close to
3852  * correct especially for very large cluster sizes --- but for newer
3853  * file systems, it's better to calculate this figure once at mkfs
3854  * time, and store it in the superblock.  If the superblock value is
3855  * present (even for non-bigalloc file systems), we will use it.
3856  */
3857 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3858                           char *buf)
3859 {
3860         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3861         struct ext4_group_desc  *gdp;
3862         ext4_fsblk_t            first_block, last_block, b;
3863         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3864         int                     s, j, count = 0;
3865
3866         if (!ext4_has_feature_bigalloc(sb))
3867                 return (ext4_bg_has_super(sb, grp) + ext4_bg_num_gdb(sb, grp) +
3868                         sbi->s_itb_per_group + 2);
3869
3870         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3871                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3872         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3873         for (i = 0; i < ngroups; i++) {
3874                 gdp = ext4_get_group_desc(sb, i, NULL);
3875                 b = ext4_block_bitmap(sb, gdp);
3876                 if (b >= first_block && b <= last_block) {
3877                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3878                         count++;
3879                 }
3880                 b = ext4_inode_bitmap(sb, gdp);
3881                 if (b >= first_block && b <= last_block) {
3882                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3883                         count++;
3884                 }
3885                 b = ext4_inode_table(sb, gdp);
3886                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3887                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3888                                 int c = EXT4_B2C(sbi, b - first_block);
3889                                 ext4_set_bit(c, buf);
3890                                 count++;
3891                         }
3892                 if (i != grp)
3893                         continue;
3894                 s = 0;
3895                 if (ext4_bg_has_super(sb, grp)) {
3896                         ext4_set_bit(s++, buf);
3897                         count++;
3898                 }
3899                 j = ext4_bg_num_gdb(sb, grp);
3900                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3901                         ext4_error(sb, "Invalid number of block group "
3902                                    "descriptor blocks: %d", j);
3903                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3904                 }
3905                 count += j;
3906                 for (; j > 0; j--)
3907                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3908         }
3909         if (!count)
3910                 return 0;
3911         return EXT4_CLUSTERS_PER_GROUP(sb) -
3912                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3913 }
3914
3915 /*
3916  * Compute the overhead and stash it in sbi->s_overhead
3917  */
3918 int ext4_calculate_overhead(struct super_block *sb)
3919 {
3920         struct ext4_sb_info *sbi = EXT4_SB(sb);
3921         struct ext4_super_block *es = sbi->s_es;
3922         struct inode *j_inode;
3923         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3924         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3925         ext4_fsblk_t overhead = 0;
3926         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3927
3928         if (!buf)
3929                 return -ENOMEM;
3930
3931         /*
3932          * Compute the overhead (FS structures).  This is constant
3933          * for a given filesystem unless the number of block groups
3934          * changes so we cache the previous value until it does.
3935          */
3936
3937         /*
3938          * All of the blocks before first_data_block are overhead
3939          */
3940         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3941
3942         /*
3943          * Add the overhead found in each block group
3944          */
3945         for (i = 0; i < ngroups; i++) {
3946                 int blks;
3947
3948                 blks = count_overhead(sb, i, buf);
3949                 overhead += blks;
3950                 if (blks)
3951                         memset(buf, 0, PAGE_SIZE);
3952                 cond_resched();
3953         }
3954
3955         /*
3956          * Add the internal journal blocks whether the journal has been
3957          * loaded or not
3958          */
3959         if (sbi->s_journal && !sbi->s_journal_bdev)
3960                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_total_len);
3961         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3962                 /* j_inum for internal journal is non-zero */
3963                 j_inode = ext4_get_journal_inode(sb, j_inum);
3964                 if (j_inode) {
3965                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3966                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3967                         iput(j_inode);
3968                 } else {
3969                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3970                 }
3971         }
3972         sbi->s_overhead = overhead;
3973         smp_wmb();
3974         free_page((unsigned long) buf);
3975         return 0;
3976 }
3977
3978 static void ext4_set_resv_clusters(struct super_block *sb)
3979 {
3980         ext4_fsblk_t resv_clusters;
3981         struct ext4_sb_info *sbi = EXT4_SB(sb);
3982
3983         /*
3984          * There's no need to reserve anything when we aren't using extents.
3985          * The space estimates are exact, there are no unwritten extents,
3986          * hole punching doesn't need new metadata... This is needed especially
3987          * to keep ext2/3 backward compatibility.
3988          */
3989         if (!ext4_has_feature_extents(sb))
3990                 return;
3991         /*
3992          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3993          * This should cover the situations where we can not afford to run
3994          * out of space like for example punch hole, or converting
3995          * unwritten extents in delalloc path. In most cases such
3996          * allocation would require 1, or 2 blocks, higher numbers are
3997          * very rare.
3998          */
3999         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
4000                          sbi->s_cluster_bits);
4001
4002         do_div(resv_clusters, 50);
4003         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
4004
4005         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
4006 }
4007
4008 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
4009 {
4010         struct dax_device *dax_dev = fs_dax_get_by_bdev(sb->s_bdev);
4011         char *orig_data = kstrdup(data, GFP_KERNEL);
4012         struct buffer_head *bh, **group_desc;
4013         struct ext4_super_block *es = NULL;
4014         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
4015         struct flex_groups **flex_groups;
4016         ext4_fsblk_t block;
4017         ext4_fsblk_t sb_block = get_sb_block(&data);
4018         ext4_fsblk_t logical_sb_block;
4019         unsigned long offset = 0;
4020         unsigned long journal_devnum = 0;
4021         unsigned long def_mount_opts;
4022         struct inode *root;
4023         const char *descr;
4024         int ret = -ENOMEM;
4025         int blocksize, clustersize;
4026         unsigned int db_count;
4027         unsigned int i;
4028         int needs_recovery, has_huge_files;
4029         __u64 blocks_count;
4030         int err = 0;
4031         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4032         ext4_group_t first_not_zeroed;
4033
4034         if ((data && !orig_data) || !sbi)
4035                 goto out_free_base;
4036
4037         sbi->s_daxdev = dax_dev;
4038         sbi->s_blockgroup_lock =
4039                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
4040         if (!sbi->s_blockgroup_lock)
4041                 goto out_free_base;
4042
4043         sb->s_fs_info = sbi;
4044         sbi->s_sb = sb;
4045         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
4046         sbi->s_sb_block = sb_block;
4047         if (sb->s_bdev->bd_part)
4048                 sbi->s_sectors_written_start =
4049                         part_stat_read(sb->s_bdev->bd_part, sectors[STAT_WRITE]);
4050
4051         /* Cleanup superblock name */
4052         strreplace(sb->s_id, '/', '!');
4053
4054         /* -EINVAL is default */
4055         ret = -EINVAL;
4056         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
4057         if (!blocksize) {
4058                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
4059                 goto out_fail;
4060         }
4061
4062         /*
4063          * The ext4 superblock will not be buffer aligned for other than 1kB
4064          * block sizes.  We need to calculate the offset from buffer start.
4065          */
4066         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
4067                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4068                 offset = do_div(logical_sb_block, blocksize);
4069         } else {
4070                 logical_sb_block = sb_block;
4071         }
4072
4073         bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4074         if (IS_ERR(bh)) {
4075                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
4076                 ret = PTR_ERR(bh);
4077                 bh = NULL;
4078                 goto out_fail;
4079         }
4080         /*
4081          * Note: s_es must be initialized as soon as possible because
4082          *       some ext4 macro-instructions depend on its value
4083          */
4084         es = (struct ext4_super_block *) (bh->b_data + offset);
4085         sbi->s_es = es;
4086         sb->s_magic = le16_to_cpu(es->s_magic);
4087         if (sb->s_magic != EXT4_SUPER_MAGIC)
4088                 goto cantfind_ext4;
4089         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
4090
4091         /* Warn if metadata_csum and gdt_csum are both set. */
4092         if (ext4_has_feature_metadata_csum(sb) &&
4093             ext4_has_feature_gdt_csum(sb))
4094                 ext4_warning(sb, "metadata_csum and uninit_bg are "
4095                              "redundant flags; please run fsck.");
4096
4097         /* Check for a known checksum algorithm */
4098         if (!ext4_verify_csum_type(sb, es)) {
4099                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4100                          "unknown checksum algorithm.");
4101                 silent = 1;
4102                 goto cantfind_ext4;
4103         }
4104
4105         /* Load the checksum driver */
4106         sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
4107         if (IS_ERR(sbi->s_chksum_driver)) {
4108                 ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
4109                 ret = PTR_ERR(sbi->s_chksum_driver);
4110                 sbi->s_chksum_driver = NULL;
4111                 goto failed_mount;
4112         }
4113
4114         /* Check superblock checksum */
4115         if (!ext4_superblock_csum_verify(sb, es)) {
4116                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
4117                          "invalid superblock checksum.  Run e2fsck?");
4118                 silent = 1;
4119                 ret = -EFSBADCRC;
4120                 goto cantfind_ext4;
4121         }
4122
4123         /* Precompute checksum seed for all metadata */
4124         if (ext4_has_feature_csum_seed(sb))
4125                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
4126         else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
4127                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
4128                                                sizeof(es->s_uuid));
4129
4130         /* Set defaults before we parse the mount options */
4131         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
4132         set_opt(sb, INIT_INODE_TABLE);
4133         if (def_mount_opts & EXT4_DEFM_DEBUG)
4134                 set_opt(sb, DEBUG);
4135         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
4136                 set_opt(sb, GRPID);
4137         if (def_mount_opts & EXT4_DEFM_UID16)
4138                 set_opt(sb, NO_UID32);
4139         /* xattr user namespace & acls are now defaulted on */
4140         set_opt(sb, XATTR_USER);
4141 #ifdef CONFIG_EXT4_FS_POSIX_ACL
4142         set_opt(sb, POSIX_ACL);
4143 #endif
4144         if (ext4_has_feature_fast_commit(sb))
4145                 set_opt2(sb, JOURNAL_FAST_COMMIT);
4146         /* don't forget to enable journal_csum when metadata_csum is enabled. */
4147         if (ext4_has_metadata_csum(sb))
4148                 set_opt(sb, JOURNAL_CHECKSUM);
4149
4150         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
4151                 set_opt(sb, JOURNAL_DATA);
4152         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
4153                 set_opt(sb, ORDERED_DATA);
4154         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
4155                 set_opt(sb, WRITEBACK_DATA);
4156
4157         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
4158                 set_opt(sb, ERRORS_PANIC);
4159         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
4160                 set_opt(sb, ERRORS_CONT);
4161         else
4162                 set_opt(sb, ERRORS_RO);
4163         /* block_validity enabled by default; disable with noblock_validity */
4164         set_opt(sb, BLOCK_VALIDITY);
4165         if (def_mount_opts & EXT4_DEFM_DISCARD)
4166                 set_opt(sb, DISCARD);
4167
4168         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
4169         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
4170         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
4171         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
4172         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
4173
4174         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
4175                 set_opt(sb, BARRIER);
4176
4177         /*
4178          * enable delayed allocation by default
4179          * Use -o nodelalloc to turn it off
4180          */
4181         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
4182             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
4183                 set_opt(sb, DELALLOC);
4184
4185         /*
4186          * set default s_li_wait_mult for lazyinit, for the case there is
4187          * no mount option specified.
4188          */
4189         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
4190
4191         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
4192
4193         if (blocksize == PAGE_SIZE)
4194                 set_opt(sb, DIOREAD_NOLOCK);
4195
4196         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
4197             blocksize > EXT4_MAX_BLOCK_SIZE) {
4198                 ext4_msg(sb, KERN_ERR,
4199                        "Unsupported filesystem blocksize %d (%d log_block_size)",
4200                          blocksize, le32_to_cpu(es->s_log_block_size));
4201                 goto failed_mount;
4202         }
4203
4204         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
4205                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
4206                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
4207         } else {
4208                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
4209                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
4210                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
4211                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
4212                                  sbi->s_first_ino);
4213                         goto failed_mount;
4214                 }
4215                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
4216                     (!is_power_of_2(sbi->s_inode_size)) ||
4217                     (sbi->s_inode_size > blocksize)) {
4218                         ext4_msg(sb, KERN_ERR,
4219                                "unsupported inode size: %d",
4220                                sbi->s_inode_size);
4221                         ext4_msg(sb, KERN_ERR, "blocksize: %d", blocksize);
4222                         goto failed_mount;
4223                 }
4224                 /*
4225                  * i_atime_extra is the last extra field available for
4226                  * [acm]times in struct ext4_inode. Checking for that
4227                  * field should suffice to ensure we have extra space
4228                  * for all three.
4229                  */
4230                 if (sbi->s_inode_size >= offsetof(struct ext4_inode, i_atime_extra) +
4231                         sizeof(((struct ext4_inode *)0)->i_atime_extra)) {
4232                         sb->s_time_gran = 1;
4233                         sb->s_time_max = EXT4_EXTRA_TIMESTAMP_MAX;
4234                 } else {
4235                         sb->s_time_gran = NSEC_PER_SEC;
4236                         sb->s_time_max = EXT4_NON_EXTRA_TIMESTAMP_MAX;
4237                 }
4238                 sb->s_time_min = EXT4_TIMESTAMP_MIN;
4239         }
4240         if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE) {
4241                 sbi->s_want_extra_isize = sizeof(struct ext4_inode) -
4242                         EXT4_GOOD_OLD_INODE_SIZE;
4243                 if (ext4_has_feature_extra_isize(sb)) {
4244                         unsigned v, max = (sbi->s_inode_size -
4245                                            EXT4_GOOD_OLD_INODE_SIZE);
4246
4247                         v = le16_to_cpu(es->s_want_extra_isize);
4248                         if (v > max) {
4249                                 ext4_msg(sb, KERN_ERR,
4250                                          "bad s_want_extra_isize: %d", v);
4251                                 goto failed_mount;
4252                         }
4253                         if (sbi->s_want_extra_isize < v)
4254                                 sbi->s_want_extra_isize = v;
4255
4256                         v = le16_to_cpu(es->s_min_extra_isize);
4257                         if (v > max) {
4258                                 ext4_msg(sb, KERN_ERR,
4259                                          "bad s_min_extra_isize: %d", v);
4260                                 goto failed_mount;
4261                         }
4262                         if (sbi->s_want_extra_isize < v)
4263                                 sbi->s_want_extra_isize = v;
4264                 }
4265         }
4266
4267         if (sbi->s_es->s_mount_opts[0]) {
4268                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
4269                                               sizeof(sbi->s_es->s_mount_opts),
4270                                               GFP_KERNEL);
4271                 if (!s_mount_opts)
4272                         goto failed_mount;
4273                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
4274                                    &journal_ioprio, 0)) {
4275                         ext4_msg(sb, KERN_WARNING,
4276                                  "failed to parse options in superblock: %s",
4277                                  s_mount_opts);
4278                 }
4279                 kfree(s_mount_opts);
4280         }
4281         sbi->s_def_mount_opt = sbi->s_mount_opt;
4282         if (!parse_options((char *) data, sb, &journal_devnum,
4283                            &journal_ioprio, 0))
4284                 goto failed_mount;
4285
4286 #ifdef CONFIG_UNICODE
4287         if (ext4_has_feature_casefold(sb) && !sb->s_encoding) {
4288                 const struct ext4_sb_encodings *encoding_info;
4289                 struct unicode_map *encoding;
4290                 __u16 encoding_flags;
4291
4292                 if (ext4_has_feature_encrypt(sb)) {
4293                         ext4_msg(sb, KERN_ERR,
4294                                  "Can't mount with encoding and encryption");
4295                         goto failed_mount;
4296                 }
4297
4298                 if (ext4_sb_read_encoding(es, &encoding_info,
4299                                           &encoding_flags)) {
4300                         ext4_msg(sb, KERN_ERR,
4301                                  "Encoding requested by superblock is unknown");
4302                         goto failed_mount;
4303                 }
4304
4305                 encoding = utf8_load(encoding_info->version);
4306                 if (IS_ERR(encoding)) {
4307                         ext4_msg(sb, KERN_ERR,
4308                                  "can't mount with superblock charset: %s-%s "
4309                                  "not supported by the kernel. flags: 0x%x.",
4310                                  encoding_info->name, encoding_info->version,
4311                                  encoding_flags);
4312                         goto failed_mount;
4313                 }
4314                 ext4_msg(sb, KERN_INFO,"Using encoding defined by superblock: "
4315                          "%s-%s with flags 0x%hx", encoding_info->name,
4316                          encoding_info->version?:"\b", encoding_flags);
4317
4318                 sb->s_encoding = encoding;
4319                 sb->s_encoding_flags = encoding_flags;
4320         }
4321 #endif
4322
4323         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
4324                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting with data=journal disables delayed allocation, dioread_nolock, O_DIRECT and fast_commit support!\n");
4325                 /* can't mount with both data=journal and dioread_nolock. */
4326                 clear_opt(sb, DIOREAD_NOLOCK);
4327                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4328                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
4329                         ext4_msg(sb, KERN_ERR, "can't mount with "
4330                                  "both data=journal and delalloc");
4331                         goto failed_mount;
4332                 }
4333                 if (test_opt(sb, DAX_ALWAYS)) {
4334                         ext4_msg(sb, KERN_ERR, "can't mount with "
4335                                  "both data=journal and dax");
4336                         goto failed_mount;
4337                 }
4338                 if (ext4_has_feature_encrypt(sb)) {
4339                         ext4_msg(sb, KERN_WARNING,
4340                                  "encrypted files will use data=ordered "
4341                                  "instead of data journaling mode");
4342                 }
4343                 if (test_opt(sb, DELALLOC))
4344                         clear_opt(sb, DELALLOC);
4345         } else {
4346                 sb->s_iflags |= SB_I_CGROUPWB;
4347         }
4348
4349         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
4350                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
4351
4352         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
4353             (ext4_has_compat_features(sb) ||
4354              ext4_has_ro_compat_features(sb) ||
4355              ext4_has_incompat_features(sb)))
4356                 ext4_msg(sb, KERN_WARNING,
4357                        "feature flags set on rev 0 fs, "
4358                        "running e2fsck is recommended");
4359
4360         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
4361                 set_opt2(sb, HURD_COMPAT);
4362                 if (ext4_has_feature_64bit(sb)) {
4363                         ext4_msg(sb, KERN_ERR,
4364                                  "The Hurd can't support 64-bit file systems");
4365                         goto failed_mount;
4366                 }
4367
4368                 /*
4369                  * ea_inode feature uses l_i_version field which is not
4370                  * available in HURD_COMPAT mode.
4371                  */
4372                 if (ext4_has_feature_ea_inode(sb)) {
4373                         ext4_msg(sb, KERN_ERR,
4374                                  "ea_inode feature is not supported for Hurd");
4375                         goto failed_mount;
4376                 }
4377         }
4378
4379         if (IS_EXT2_SB(sb)) {
4380                 if (ext2_feature_set_ok(sb))
4381                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
4382                                  "using the ext4 subsystem");
4383                 else {
4384                         /*
4385                          * If we're probing be silent, if this looks like
4386                          * it's actually an ext[34] filesystem.
4387                          */
4388                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4389                                 goto failed_mount;
4390                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
4391                                  "to feature incompatibilities");
4392                         goto failed_mount;
4393                 }
4394         }
4395
4396         if (IS_EXT3_SB(sb)) {
4397                 if (ext3_feature_set_ok(sb))
4398                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
4399                                  "using the ext4 subsystem");
4400                 else {
4401                         /*
4402                          * If we're probing be silent, if this looks like
4403                          * it's actually an ext4 filesystem.
4404                          */
4405                         if (silent && ext4_feature_set_ok(sb, sb_rdonly(sb)))
4406                                 goto failed_mount;
4407                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
4408                                  "to feature incompatibilities");
4409                         goto failed_mount;
4410                 }
4411         }
4412
4413         /*
4414          * Check feature flags regardless of the revision level, since we
4415          * previously didn't change the revision level when setting the flags,
4416          * so there is a chance incompat flags are set on a rev 0 filesystem.
4417          */
4418         if (!ext4_feature_set_ok(sb, (sb_rdonly(sb))))
4419                 goto failed_mount;
4420
4421         if (le32_to_cpu(es->s_log_block_size) >
4422             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4423                 ext4_msg(sb, KERN_ERR,
4424                          "Invalid log block size: %u",
4425                          le32_to_cpu(es->s_log_block_size));
4426                 goto failed_mount;
4427         }
4428         if (le32_to_cpu(es->s_log_cluster_size) >
4429             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
4430                 ext4_msg(sb, KERN_ERR,
4431                          "Invalid log cluster size: %u",
4432                          le32_to_cpu(es->s_log_cluster_size));
4433                 goto failed_mount;
4434         }
4435
4436         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
4437                 ext4_msg(sb, KERN_ERR,
4438                          "Number of reserved GDT blocks insanely large: %d",
4439                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
4440                 goto failed_mount;
4441         }
4442
4443         if (bdev_dax_supported(sb->s_bdev, blocksize))
4444                 set_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags);
4445
4446         if (sbi->s_mount_opt & EXT4_MOUNT_DAX_ALWAYS) {
4447                 if (ext4_has_feature_inline_data(sb)) {
4448                         ext4_msg(sb, KERN_ERR, "Cannot use DAX on a filesystem"
4449                                         " that may contain inline data");
4450                         goto failed_mount;
4451                 }
4452                 if (!test_bit(EXT4_FLAGS_BDEV_IS_DAX, &sbi->s_ext4_flags)) {
4453                         ext4_msg(sb, KERN_ERR,
4454                                 "DAX unsupported by block device.");
4455                         goto failed_mount;
4456                 }
4457         }
4458
4459         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
4460                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
4461                          es->s_encryption_level);
4462                 goto failed_mount;
4463         }
4464
4465         if (sb->s_blocksize != blocksize) {
4466                 /* Validate the filesystem blocksize */
4467                 if (!sb_set_blocksize(sb, blocksize)) {
4468                         ext4_msg(sb, KERN_ERR, "bad block size %d",
4469                                         blocksize);
4470                         goto failed_mount;
4471                 }
4472
4473                 brelse(bh);
4474                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
4475                 offset = do_div(logical_sb_block, blocksize);
4476                 bh = ext4_sb_bread_unmovable(sb, logical_sb_block);
4477                 if (IS_ERR(bh)) {
4478                         ext4_msg(sb, KERN_ERR,
4479                                "Can't read superblock on 2nd try");
4480                         ret = PTR_ERR(bh);
4481                         bh = NULL;
4482                         goto failed_mount;
4483                 }
4484                 es = (struct ext4_super_block *)(bh->b_data + offset);
4485                 sbi->s_es = es;
4486                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
4487                         ext4_msg(sb, KERN_ERR,
4488                                "Magic mismatch, very weird!");
4489                         goto failed_mount;
4490                 }
4491         }
4492
4493         has_huge_files = ext4_has_feature_huge_file(sb);
4494         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
4495                                                       has_huge_files);
4496         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
4497
4498         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
4499         if (ext4_has_feature_64bit(sb)) {
4500                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
4501                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
4502                     !is_power_of_2(sbi->s_desc_size)) {
4503                         ext4_msg(sb, KERN_ERR,
4504                                "unsupported descriptor size %lu",
4505                                sbi->s_desc_size);
4506                         goto failed_mount;
4507                 }
4508         } else
4509                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
4510
4511         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
4512         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
4513
4514         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
4515         if (sbi->s_inodes_per_block == 0)
4516                 goto cantfind_ext4;
4517         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
4518             sbi->s_inodes_per_group > blocksize * 8) {
4519                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
4520                          sbi->s_inodes_per_group);
4521                 goto failed_mount;
4522         }
4523         sbi->s_itb_per_group = sbi->s_inodes_per_group /
4524                                         sbi->s_inodes_per_block;
4525         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
4526         sbi->s_sbh = bh;
4527         sbi->s_mount_state = le16_to_cpu(es->s_state);
4528         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
4529         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
4530
4531         for (i = 0; i < 4; i++)
4532                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
4533         sbi->s_def_hash_version = es->s_def_hash_version;
4534         if (ext4_has_feature_dir_index(sb)) {
4535                 i = le32_to_cpu(es->s_flags);
4536                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
4537                         sbi->s_hash_unsigned = 3;
4538                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
4539 #ifdef __CHAR_UNSIGNED__
4540                         if (!sb_rdonly(sb))
4541                                 es->s_flags |=
4542                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
4543                         sbi->s_hash_unsigned = 3;
4544 #else
4545                         if (!sb_rdonly(sb))
4546                                 es->s_flags |=
4547                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
4548 #endif
4549                 }
4550         }
4551
4552         /* Handle clustersize */
4553         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
4554         if (ext4_has_feature_bigalloc(sb)) {
4555                 if (clustersize < blocksize) {
4556                         ext4_msg(sb, KERN_ERR,
4557                                  "cluster size (%d) smaller than "
4558                                  "block size (%d)", clustersize, blocksize);
4559                         goto failed_mount;
4560                 }
4561                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
4562                         le32_to_cpu(es->s_log_block_size);
4563                 sbi->s_clusters_per_group =
4564                         le32_to_cpu(es->s_clusters_per_group);
4565                 if (sbi->s_clusters_per_group > blocksize * 8) {
4566                         ext4_msg(sb, KERN_ERR,
4567                                  "#clusters per group too big: %lu",
4568                                  sbi->s_clusters_per_group);
4569                         goto failed_mount;
4570                 }
4571                 if (sbi->s_blocks_per_group !=
4572                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
4573                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
4574                                  "clusters per group (%lu) inconsistent",
4575                                  sbi->s_blocks_per_group,
4576                                  sbi->s_clusters_per_group);
4577                         goto failed_mount;
4578                 }
4579         } else {
4580                 if (clustersize != blocksize) {
4581                         ext4_msg(sb, KERN_ERR,
4582                                  "fragment/cluster size (%d) != "
4583                                  "block size (%d)", clustersize, blocksize);
4584                         goto failed_mount;
4585                 }
4586                 if (sbi->s_blocks_per_group > blocksize * 8) {
4587                         ext4_msg(sb, KERN_ERR,
4588                                  "#blocks per group too big: %lu",
4589                                  sbi->s_blocks_per_group);
4590                         goto failed_mount;
4591                 }
4592                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
4593                 sbi->s_cluster_bits = 0;
4594         }
4595         sbi->s_cluster_ratio = clustersize / blocksize;
4596
4597         /* Do we have standard group size of clustersize * 8 blocks ? */
4598         if (sbi->s_blocks_per_group == clustersize << 3)
4599                 set_opt2(sb, STD_GROUP_SIZE);
4600
4601         /*
4602          * Test whether we have more sectors than will fit in sector_t,
4603          * and whether the max offset is addressable by the page cache.
4604          */
4605         err = generic_check_addressable(sb->s_blocksize_bits,
4606                                         ext4_blocks_count(es));
4607         if (err) {
4608                 ext4_msg(sb, KERN_ERR, "filesystem"
4609                          " too large to mount safely on this system");
4610                 goto failed_mount;
4611         }
4612
4613         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
4614                 goto cantfind_ext4;
4615
4616         /* check blocks count against device size */
4617         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
4618         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
4619                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
4620                        "exceeds size of device (%llu blocks)",
4621                        ext4_blocks_count(es), blocks_count);
4622                 goto failed_mount;
4623         }
4624
4625         /*
4626          * It makes no sense for the first data block to be beyond the end
4627          * of the filesystem.
4628          */
4629         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
4630                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4631                          "block %u is beyond end of filesystem (%llu)",
4632                          le32_to_cpu(es->s_first_data_block),
4633                          ext4_blocks_count(es));
4634                 goto failed_mount;
4635         }
4636         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
4637             (sbi->s_cluster_ratio == 1)) {
4638                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
4639                          "block is 0 with a 1k block and cluster size");
4640                 goto failed_mount;
4641         }
4642
4643         blocks_count = (ext4_blocks_count(es) -
4644                         le32_to_cpu(es->s_first_data_block) +
4645                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
4646         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
4647         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
4648                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
4649                        "(block count %llu, first data block %u, "
4650                        "blocks per group %lu)", blocks_count,
4651                        ext4_blocks_count(es),
4652                        le32_to_cpu(es->s_first_data_block),
4653                        EXT4_BLOCKS_PER_GROUP(sb));
4654                 goto failed_mount;
4655         }
4656         sbi->s_groups_count = blocks_count;
4657         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
4658                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
4659         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
4660             le32_to_cpu(es->s_inodes_count)) {
4661                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
4662                          le32_to_cpu(es->s_inodes_count),
4663                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
4664                 ret = -EINVAL;
4665                 goto failed_mount;
4666         }
4667         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
4668                    EXT4_DESC_PER_BLOCK(sb);
4669         if (ext4_has_feature_meta_bg(sb)) {
4670                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
4671                         ext4_msg(sb, KERN_WARNING,
4672                                  "first meta block group too large: %u "
4673                                  "(group descriptor block count %u)",
4674                                  le32_to_cpu(es->s_first_meta_bg), db_count);
4675                         goto failed_mount;
4676                 }
4677         }
4678         rcu_assign_pointer(sbi->s_group_desc,
4679                            kvmalloc_array(db_count,
4680                                           sizeof(struct buffer_head *),
4681                                           GFP_KERNEL));
4682         if (sbi->s_group_desc == NULL) {
4683                 ext4_msg(sb, KERN_ERR, "not enough memory");
4684                 ret = -ENOMEM;
4685                 goto failed_mount;
4686         }
4687
4688         bgl_lock_init(sbi->s_blockgroup_lock);
4689
4690         /* Pre-read the descriptors into the buffer cache */
4691         for (i = 0; i < db_count; i++) {
4692                 block = descriptor_loc(sb, logical_sb_block, i);
4693                 ext4_sb_breadahead_unmovable(sb, block);
4694         }
4695
4696         for (i = 0; i < db_count; i++) {
4697                 struct buffer_head *bh;
4698
4699                 block = descriptor_loc(sb, logical_sb_block, i);
4700                 bh = ext4_sb_bread_unmovable(sb, block);
4701                 if (IS_ERR(bh)) {
4702                         ext4_msg(sb, KERN_ERR,
4703                                "can't read group descriptor %d", i);
4704                         db_count = i;
4705                         ret = PTR_ERR(bh);
4706                         bh = NULL;
4707                         goto failed_mount2;
4708                 }
4709                 rcu_read_lock();
4710                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4711                 rcu_read_unlock();
4712         }
4713         sbi->s_gdb_count = db_count;
4714         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4715                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4716                 ret = -EFSCORRUPTED;
4717                 goto failed_mount2;
4718         }
4719
4720         timer_setup(&sbi->s_err_report, print_daily_error_info, 0);
4721
4722         /* Register extent status tree shrinker */
4723         if (ext4_es_register_shrinker(sbi))
4724                 goto failed_mount3;
4725
4726         sbi->s_stripe = ext4_get_stripe_size(sbi);
4727         sbi->s_extent_max_zeroout_kb = 32;
4728
4729         /*
4730          * set up enough so that it can read an inode
4731          */
4732         sb->s_op = &ext4_sops;
4733         sb->s_export_op = &ext4_export_ops;
4734         sb->s_xattr = ext4_xattr_handlers;
4735 #ifdef CONFIG_FS_ENCRYPTION
4736         sb->s_cop = &ext4_cryptops;
4737 #endif
4738 #ifdef CONFIG_FS_VERITY
4739         sb->s_vop = &ext4_verityops;
4740 #endif
4741 #ifdef CONFIG_QUOTA
4742         sb->dq_op = &ext4_quota_operations;
4743         if (ext4_has_feature_quota(sb))
4744                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4745         else
4746                 sb->s_qcop = &ext4_qctl_operations;
4747         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4748 #endif
4749         memcpy(&sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4750
4751         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4752         mutex_init(&sbi->s_orphan_lock);
4753
4754         /* Initialize fast commit stuff */
4755         atomic_set(&sbi->s_fc_subtid, 0);
4756         atomic_set(&sbi->s_fc_ineligible_updates, 0);
4757         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_MAIN]);
4758         INIT_LIST_HEAD(&sbi->s_fc_q[FC_Q_STAGING]);
4759         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_MAIN]);
4760         INIT_LIST_HEAD(&sbi->s_fc_dentry_q[FC_Q_STAGING]);
4761         sbi->s_fc_bytes = 0;
4762         ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
4763         ext4_clear_mount_flag(sb, EXT4_MF_FC_COMMITTING);
4764         spin_lock_init(&sbi->s_fc_lock);
4765         memset(&sbi->s_fc_stats, 0, sizeof(sbi->s_fc_stats));
4766         sbi->s_fc_replay_state.fc_regions = NULL;
4767         sbi->s_fc_replay_state.fc_regions_size = 0;
4768         sbi->s_fc_replay_state.fc_regions_used = 0;
4769         sbi->s_fc_replay_state.fc_regions_valid = 0;
4770         sbi->s_fc_replay_state.fc_modified_inodes = NULL;
4771         sbi->s_fc_replay_state.fc_modified_inodes_size = 0;
4772         sbi->s_fc_replay_state.fc_modified_inodes_used = 0;
4773
4774         sb->s_root = NULL;
4775
4776         needs_recovery = (es->s_last_orphan != 0 ||
4777                           ext4_has_feature_journal_needs_recovery(sb));
4778
4779         if (ext4_has_feature_mmp(sb) && !sb_rdonly(sb))
4780                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4781                         goto failed_mount3a;
4782
4783         /*
4784          * The first inode we look at is the journal inode.  Don't try
4785          * root first: it may be modified in the journal!
4786          */
4787         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4788                 err = ext4_load_journal(sb, es, journal_devnum);
4789                 if (err)
4790                         goto failed_mount3a;
4791         } else if (test_opt(sb, NOLOAD) && !sb_rdonly(sb) &&
4792                    ext4_has_feature_journal_needs_recovery(sb)) {
4793                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4794                        "suppressed and not mounted read-only");
4795                 goto failed_mount_wq;
4796         } else {
4797                 /* Nojournal mode, all journal mount options are illegal */
4798                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4799                         ext4_msg(sb, KERN_ERR, "can't mount with "
4800                                  "journal_checksum, fs mounted w/o journal");
4801                         goto failed_mount_wq;
4802                 }
4803                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4804                         ext4_msg(sb, KERN_ERR, "can't mount with "
4805                                  "journal_async_commit, fs mounted w/o journal");
4806                         goto failed_mount_wq;
4807                 }
4808                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4809                         ext4_msg(sb, KERN_ERR, "can't mount with "
4810                                  "commit=%lu, fs mounted w/o journal",
4811                                  sbi->s_commit_interval / HZ);
4812                         goto failed_mount_wq;
4813                 }
4814                 if (EXT4_MOUNT_DATA_FLAGS &
4815                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4816                         ext4_msg(sb, KERN_ERR, "can't mount with "
4817                                  "data=, fs mounted w/o journal");
4818                         goto failed_mount_wq;
4819                 }
4820                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4821                 clear_opt(sb, JOURNAL_CHECKSUM);
4822                 clear_opt(sb, DATA_FLAGS);
4823                 clear_opt2(sb, JOURNAL_FAST_COMMIT);
4824                 sbi->s_journal = NULL;
4825                 needs_recovery = 0;
4826                 goto no_journal;
4827         }
4828
4829         if (ext4_has_feature_64bit(sb) &&
4830             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4831                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4832                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4833                 goto failed_mount_wq;
4834         }
4835
4836         if (!set_journal_csum_feature_set(sb)) {
4837                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4838                          "feature set");
4839                 goto failed_mount_wq;
4840         }
4841
4842         if (test_opt2(sb, JOURNAL_FAST_COMMIT) &&
4843                 !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4844                                           JBD2_FEATURE_INCOMPAT_FAST_COMMIT)) {
4845                 ext4_msg(sb, KERN_ERR,
4846                         "Failed to set fast commit journal feature");
4847                 goto failed_mount_wq;
4848         }
4849
4850         /* We have now updated the journal if required, so we can
4851          * validate the data journaling mode. */
4852         switch (test_opt(sb, DATA_FLAGS)) {
4853         case 0:
4854                 /* No mode set, assume a default based on the journal
4855                  * capabilities: ORDERED_DATA if the journal can
4856                  * cope, else JOURNAL_DATA
4857                  */
4858                 if (jbd2_journal_check_available_features
4859                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4860                         set_opt(sb, ORDERED_DATA);
4861                         sbi->s_def_mount_opt |= EXT4_MOUNT_ORDERED_DATA;
4862                 } else {
4863                         set_opt(sb, JOURNAL_DATA);
4864                         sbi->s_def_mount_opt |= EXT4_MOUNT_JOURNAL_DATA;
4865                 }
4866                 break;
4867
4868         case EXT4_MOUNT_ORDERED_DATA:
4869         case EXT4_MOUNT_WRITEBACK_DATA:
4870                 if (!jbd2_journal_check_available_features
4871                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4872                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4873                                "requested data journaling mode");
4874                         goto failed_mount_wq;
4875                 }
4876         default:
4877                 break;
4878         }
4879
4880         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
4881             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4882                 ext4_msg(sb, KERN_ERR, "can't mount with "
4883                         "journal_async_commit in data=ordered mode");
4884                 goto failed_mount_wq;
4885         }
4886
4887         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4888
4889         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4890         sbi->s_journal->j_submit_inode_data_buffers =
4891                 ext4_journal_submit_inode_data_buffers;
4892         sbi->s_journal->j_finish_inode_data_buffers =
4893                 ext4_journal_finish_inode_data_buffers;
4894
4895 no_journal:
4896         if (!test_opt(sb, NO_MBCACHE)) {
4897                 sbi->s_ea_block_cache = ext4_xattr_create_cache();
4898                 if (!sbi->s_ea_block_cache) {
4899                         ext4_msg(sb, KERN_ERR,
4900                                  "Failed to create ea_block_cache");
4901                         goto failed_mount_wq;
4902                 }
4903
4904                 if (ext4_has_feature_ea_inode(sb)) {
4905                         sbi->s_ea_inode_cache = ext4_xattr_create_cache();
4906                         if (!sbi->s_ea_inode_cache) {
4907                                 ext4_msg(sb, KERN_ERR,
4908                                          "Failed to create ea_inode_cache");
4909                                 goto failed_mount_wq;
4910                         }
4911                 }
4912         }
4913
4914         if (ext4_has_feature_verity(sb) && blocksize != PAGE_SIZE) {
4915                 ext4_msg(sb, KERN_ERR, "Unsupported blocksize for fs-verity");
4916                 goto failed_mount_wq;
4917         }
4918
4919         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !sb_rdonly(sb) &&
4920             !ext4_has_feature_encrypt(sb)) {
4921                 ext4_set_feature_encrypt(sb);
4922                 ext4_commit_super(sb, 1);
4923         }
4924
4925         /*
4926          * Get the # of file system overhead blocks from the
4927          * superblock if present.
4928          */
4929         if (es->s_overhead_clusters)
4930                 sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4931         else {
4932                 err = ext4_calculate_overhead(sb);
4933                 if (err)
4934                         goto failed_mount_wq;
4935         }
4936
4937         /*
4938          * The maximum number of concurrent works can be high and
4939          * concurrency isn't really necessary.  Limit it to 1.
4940          */
4941         EXT4_SB(sb)->rsv_conversion_wq =
4942                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4943         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4944                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4945                 ret = -ENOMEM;
4946                 goto failed_mount4;
4947         }
4948
4949         /*
4950          * The jbd2_journal_load will have done any necessary log recovery,
4951          * so we can safely mount the rest of the filesystem now.
4952          */
4953
4954         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4955         if (IS_ERR(root)) {
4956                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4957                 ret = PTR_ERR(root);
4958                 root = NULL;
4959                 goto failed_mount4;
4960         }
4961         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4962                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4963                 iput(root);
4964                 goto failed_mount4;
4965         }
4966
4967 #ifdef CONFIG_UNICODE
4968         if (sb->s_encoding)
4969                 sb->s_d_op = &ext4_dentry_ops;
4970 #endif
4971
4972         sb->s_root = d_make_root(root);
4973         if (!sb->s_root) {
4974                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4975                 ret = -ENOMEM;
4976                 goto failed_mount4;
4977         }
4978
4979         ret = ext4_setup_super(sb, es, sb_rdonly(sb));
4980         if (ret == -EROFS) {
4981                 sb->s_flags |= SB_RDONLY;
4982                 ret = 0;
4983         } else if (ret)
4984                 goto failed_mount4a;
4985
4986         ext4_set_resv_clusters(sb);
4987
4988         if (test_opt(sb, BLOCK_VALIDITY)) {
4989                 err = ext4_setup_system_zone(sb);
4990                 if (err) {
4991                         ext4_msg(sb, KERN_ERR, "failed to initialize system "
4992                                  "zone (%d)", err);
4993                         goto failed_mount4a;
4994                 }
4995         }
4996         ext4_fc_replay_cleanup(sb);
4997
4998         ext4_ext_init(sb);
4999         err = ext4_mb_init(sb);
5000         if (err) {
5001                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
5002                          err);
5003                 goto failed_mount5;
5004         }
5005
5006         block = ext4_count_free_clusters(sb);
5007         ext4_free_blocks_count_set(sbi->s_es, 
5008                                    EXT4_C2B(sbi, block));
5009         ext4_superblock_csum_set(sb);
5010         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
5011                                   GFP_KERNEL);
5012         if (!err) {
5013                 unsigned long freei = ext4_count_free_inodes(sb);
5014                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
5015                 ext4_superblock_csum_set(sb);
5016                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
5017                                           GFP_KERNEL);
5018         }
5019         if (!err)
5020                 err = percpu_counter_init(&sbi->s_dirs_counter,
5021                                           ext4_count_dirs(sb), GFP_KERNEL);
5022         if (!err)
5023                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
5024                                           GFP_KERNEL);
5025         if (!err)
5026                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
5027
5028         if (err) {
5029                 ext4_msg(sb, KERN_ERR, "insufficient memory");
5030                 goto failed_mount6;
5031         }
5032
5033         if (ext4_has_feature_flex_bg(sb))
5034                 if (!ext4_fill_flex_info(sb)) {
5035                         ext4_msg(sb, KERN_ERR,
5036                                "unable to initialize "
5037                                "flex_bg meta info!");
5038                         goto failed_mount6;
5039                 }
5040
5041         err = ext4_register_li_request(sb, first_not_zeroed);
5042         if (err)
5043                 goto failed_mount6;
5044
5045         err = ext4_register_sysfs(sb);
5046         if (err)
5047                 goto failed_mount7;
5048
5049 #ifdef CONFIG_QUOTA
5050         /* Enable quota usage during mount. */
5051         if (ext4_has_feature_quota(sb) && !sb_rdonly(sb)) {
5052                 err = ext4_enable_quotas(sb);
5053                 if (err)
5054                         goto failed_mount8;
5055         }
5056 #endif  /* CONFIG_QUOTA */
5057
5058         /*
5059          * Save the original bdev mapping's wb_err value which could be
5060          * used to detect the metadata async write error.
5061          */
5062         spin_lock_init(&sbi->s_bdev_wb_lock);
5063         errseq_check_and_advance(&sb->s_bdev->bd_inode->i_mapping->wb_err,
5064                                  &sbi->s_bdev_wb_err);
5065         sb->s_bdev->bd_super = sb;
5066         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
5067         ext4_orphan_cleanup(sb, es);
5068         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
5069         if (needs_recovery) {
5070                 ext4_msg(sb, KERN_INFO, "recovery complete");
5071                 err = ext4_mark_recovery_complete(sb, es);
5072                 if (err)
5073                         goto failed_mount8;
5074         }
5075         if (EXT4_SB(sb)->s_journal) {
5076                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
5077                         descr = " journalled data mode";
5078                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
5079                         descr = " ordered data mode";
5080                 else
5081                         descr = " writeback data mode";
5082         } else
5083                 descr = "out journal";
5084
5085         if (test_opt(sb, DISCARD)) {
5086                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
5087                 if (!blk_queue_discard(q))
5088                         ext4_msg(sb, KERN_WARNING,
5089                                  "mounting with \"discard\" option, but "
5090                                  "the device does not support discard");
5091         }
5092
5093         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
5094                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
5095                          "Opts: %.*s%s%s", descr,
5096                          (int) sizeof(sbi->s_es->s_mount_opts),
5097                          sbi->s_es->s_mount_opts,
5098                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
5099
5100         if (es->s_error_count)
5101                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
5102
5103         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
5104         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
5105         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
5106         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
5107         atomic_set(&sbi->s_warning_count, 0);
5108         atomic_set(&sbi->s_msg_count, 0);
5109
5110         kfree(orig_data);
5111         return 0;
5112
5113 cantfind_ext4:
5114         if (!silent)
5115                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
5116         goto failed_mount;
5117
5118 failed_mount8:
5119         ext4_unregister_sysfs(sb);
5120         kobject_put(&sbi->s_kobj);
5121 failed_mount7:
5122         ext4_unregister_li_request(sb);
5123 failed_mount6:
5124         ext4_mb_release(sb);
5125         rcu_read_lock();
5126         flex_groups = rcu_dereference(sbi->s_flex_groups);
5127         if (flex_groups) {
5128                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
5129                         kvfree(flex_groups[i]);
5130                 kvfree(flex_groups);
5131         }
5132         rcu_read_unlock();
5133         percpu_counter_destroy(&sbi->s_freeclusters_counter);
5134         percpu_counter_destroy(&sbi->s_freeinodes_counter);
5135         percpu_counter_destroy(&sbi->s_dirs_counter);
5136         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
5137         percpu_free_rwsem(&sbi->s_writepages_rwsem);
5138 failed_mount5:
5139         ext4_ext_release(sb);
5140         ext4_release_system_zone(sb);
5141 failed_mount4a:
5142         dput(sb->s_root);
5143         sb->s_root = NULL;
5144 failed_mount4:
5145         ext4_msg(sb, KERN_ERR, "mount failed");
5146         if (EXT4_SB(sb)->rsv_conversion_wq)
5147                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
5148 failed_mount_wq:
5149         ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
5150         sbi->s_ea_inode_cache = NULL;
5151
5152         ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
5153         sbi->s_ea_block_cache = NULL;
5154
5155         if (sbi->s_journal) {
5156                 jbd2_journal_destroy(sbi->s_journal);
5157                 sbi->s_journal = NULL;
5158         }
5159 failed_mount3a:
5160         ext4_es_unregister_shrinker(sbi);
5161 failed_mount3:
5162         del_timer_sync(&sbi->s_err_report);
5163         if (sbi->s_mmp_tsk)
5164                 kthread_stop(sbi->s_mmp_tsk);
5165 failed_mount2:
5166         rcu_read_lock();
5167         group_desc = rcu_dereference(sbi->s_group_desc);
5168         for (i = 0; i < db_count; i++)
5169                 brelse(group_desc[i]);
5170         kvfree(group_desc);
5171         rcu_read_unlock();
5172 failed_mount:
5173         if (sbi->s_chksum_driver)
5174                 crypto_free_shash(sbi->s_chksum_driver);
5175
5176 #ifdef CONFIG_UNICODE
5177         utf8_unload(sb->s_encoding);
5178 #endif
5179
5180 #ifdef CONFIG_QUOTA
5181         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5182                 kfree(get_qf_name(sb, sbi, i));
5183 #endif
5184         fscrypt_free_dummy_policy(&sbi->s_dummy_enc_policy);
5185         ext4_blkdev_remove(sbi);
5186         brelse(bh);
5187 out_fail:
5188         sb->s_fs_info = NULL;
5189         kfree(sbi->s_blockgroup_lock);
5190 out_free_base:
5191         kfree(sbi);
5192         kfree(orig_data);
5193         fs_put_dax(dax_dev);
5194         return err ? err : ret;
5195 }
5196
5197 /*
5198  * Setup any per-fs journal parameters now.  We'll do this both on
5199  * initial mount, once the journal has been initialised but before we've
5200  * done any recovery; and again on any subsequent remount.
5201  */
5202 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
5203 {
5204         struct ext4_sb_info *sbi = EXT4_SB(sb);
5205
5206         journal->j_commit_interval = sbi->s_commit_interval;
5207         journal->j_min_batch_time = sbi->s_min_batch_time;
5208         journal->j_max_batch_time = sbi->s_max_batch_time;
5209         ext4_fc_init(sb, journal);
5210
5211         write_lock(&journal->j_state_lock);
5212         if (test_opt(sb, BARRIER))
5213                 journal->j_flags |= JBD2_BARRIER;
5214         else
5215                 journal->j_flags &= ~JBD2_BARRIER;
5216         if (test_opt(sb, DATA_ERR_ABORT))
5217                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
5218         else
5219                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
5220         write_unlock(&journal->j_state_lock);
5221 }
5222
5223 static struct inode *ext4_get_journal_inode(struct super_block *sb,
5224                                              unsigned int journal_inum)
5225 {
5226         struct inode *journal_inode;
5227
5228         /*
5229          * Test for the existence of a valid inode on disk.  Bad things
5230          * happen if we iget() an unused inode, as the subsequent iput()
5231          * will try to delete it.
5232          */
5233         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
5234         if (IS_ERR(journal_inode)) {
5235                 ext4_msg(sb, KERN_ERR, "no journal found");
5236                 return NULL;
5237         }
5238         if (!journal_inode->i_nlink) {
5239                 make_bad_inode(journal_inode);
5240                 iput(journal_inode);
5241                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
5242                 return NULL;
5243         }
5244
5245         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
5246                   journal_inode, journal_inode->i_size);
5247         if (!S_ISREG(journal_inode->i_mode)) {
5248                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
5249                 iput(journal_inode);
5250                 return NULL;
5251         }
5252         return journal_inode;
5253 }
5254
5255 static journal_t *ext4_get_journal(struct super_block *sb,
5256                                    unsigned int journal_inum)
5257 {
5258         struct inode *journal_inode;
5259         journal_t *journal;
5260
5261         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5262                 return NULL;
5263
5264         journal_inode = ext4_get_journal_inode(sb, journal_inum);
5265         if (!journal_inode)
5266                 return NULL;
5267
5268         journal = jbd2_journal_init_inode(journal_inode);
5269         if (!journal) {
5270                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
5271                 iput(journal_inode);
5272                 return NULL;
5273         }
5274         journal->j_private = sb;
5275         ext4_init_journal_params(sb, journal);
5276         return journal;
5277 }
5278
5279 static journal_t *ext4_get_dev_journal(struct super_block *sb,
5280                                        dev_t j_dev)
5281 {
5282         struct buffer_head *bh;
5283         journal_t *journal;
5284         ext4_fsblk_t start;
5285         ext4_fsblk_t len;
5286         int hblock, blocksize;
5287         ext4_fsblk_t sb_block;
5288         unsigned long offset;
5289         struct ext4_super_block *es;
5290         struct block_device *bdev;
5291
5292         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5293                 return NULL;
5294
5295         bdev = ext4_blkdev_get(j_dev, sb);
5296         if (bdev == NULL)
5297                 return NULL;
5298
5299         blocksize = sb->s_blocksize;
5300         hblock = bdev_logical_block_size(bdev);
5301         if (blocksize < hblock) {
5302                 ext4_msg(sb, KERN_ERR,
5303                         "blocksize too small for journal device");
5304                 goto out_bdev;
5305         }
5306
5307         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
5308         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
5309         set_blocksize(bdev, blocksize);
5310         if (!(bh = __bread(bdev, sb_block, blocksize))) {
5311                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
5312                        "external journal");
5313                 goto out_bdev;
5314         }
5315
5316         es = (struct ext4_super_block *) (bh->b_data + offset);
5317         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
5318             !(le32_to_cpu(es->s_feature_incompat) &
5319               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
5320                 ext4_msg(sb, KERN_ERR, "external journal has "
5321                                         "bad superblock");
5322                 brelse(bh);
5323                 goto out_bdev;
5324         }
5325
5326         if ((le32_to_cpu(es->s_feature_ro_compat) &
5327              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
5328             es->s_checksum != ext4_superblock_csum(sb, es)) {
5329                 ext4_msg(sb, KERN_ERR, "external journal has "
5330                                        "corrupt superblock");
5331                 brelse(bh);
5332                 goto out_bdev;
5333         }
5334
5335         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
5336                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
5337                 brelse(bh);
5338                 goto out_bdev;
5339         }
5340
5341         len = ext4_blocks_count(es);
5342         start = sb_block + 1;
5343         brelse(bh);     /* we're done with the superblock */
5344
5345         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
5346                                         start, len, blocksize);
5347         if (!journal) {
5348                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
5349                 goto out_bdev;
5350         }
5351         journal->j_private = sb;
5352         if (ext4_read_bh_lock(journal->j_sb_buffer, REQ_META | REQ_PRIO, true)) {
5353                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
5354                 goto out_journal;
5355         }
5356         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
5357                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
5358                                         "user (unsupported) - %d",
5359                         be32_to_cpu(journal->j_superblock->s_nr_users));
5360                 goto out_journal;
5361         }
5362         EXT4_SB(sb)->s_journal_bdev = bdev;
5363         ext4_init_journal_params(sb, journal);
5364         return journal;
5365
5366 out_journal:
5367         jbd2_journal_destroy(journal);
5368 out_bdev:
5369         ext4_blkdev_put(bdev);
5370         return NULL;
5371 }
5372
5373 static int ext4_load_journal(struct super_block *sb,
5374                              struct ext4_super_block *es,
5375                              unsigned long journal_devnum)
5376 {
5377         journal_t *journal;
5378         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
5379         dev_t journal_dev;
5380         int err = 0;
5381         int really_read_only;
5382         int journal_dev_ro;
5383
5384         if (WARN_ON_ONCE(!ext4_has_feature_journal(sb)))
5385                 return -EFSCORRUPTED;
5386
5387         if (journal_devnum &&
5388             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5389                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
5390                         "numbers have changed");
5391                 journal_dev = new_decode_dev(journal_devnum);
5392         } else
5393                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
5394
5395         if (journal_inum && journal_dev) {
5396                 ext4_msg(sb, KERN_ERR,
5397                          "filesystem has both journal inode and journal device!");
5398                 return -EINVAL;
5399         }
5400
5401         if (journal_inum) {
5402                 journal = ext4_get_journal(sb, journal_inum);
5403                 if (!journal)
5404                         return -EINVAL;
5405         } else {
5406                 journal = ext4_get_dev_journal(sb, journal_dev);
5407                 if (!journal)
5408                         return -EINVAL;
5409         }
5410
5411         journal_dev_ro = bdev_read_only(journal->j_dev);
5412         really_read_only = bdev_read_only(sb->s_bdev) | journal_dev_ro;
5413
5414         if (journal_dev_ro && !sb_rdonly(sb)) {
5415                 ext4_msg(sb, KERN_ERR,
5416                          "journal device read-only, try mounting with '-o ro'");
5417                 err = -EROFS;
5418                 goto err_out;
5419         }
5420
5421         /*
5422          * Are we loading a blank journal or performing recovery after a
5423          * crash?  For recovery, we need to check in advance whether we
5424          * can get read-write access to the device.
5425          */
5426         if (ext4_has_feature_journal_needs_recovery(sb)) {
5427                 if (sb_rdonly(sb)) {
5428                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
5429                                         "required on readonly filesystem");
5430                         if (really_read_only) {
5431                                 ext4_msg(sb, KERN_ERR, "write access "
5432                                         "unavailable, cannot proceed "
5433                                         "(try mounting with noload)");
5434                                 err = -EROFS;
5435                                 goto err_out;
5436                         }
5437                         ext4_msg(sb, KERN_INFO, "write access will "
5438                                "be enabled during recovery");
5439                 }
5440         }
5441
5442         if (!(journal->j_flags & JBD2_BARRIER))
5443                 ext4_msg(sb, KERN_INFO, "barriers disabled");
5444
5445         if (!ext4_has_feature_journal_needs_recovery(sb))
5446                 err = jbd2_journal_wipe(journal, !really_read_only);
5447         if (!err) {
5448                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
5449                 if (save)
5450                         memcpy(save, ((char *) es) +
5451                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
5452                 err = jbd2_journal_load(journal);
5453                 if (save)
5454                         memcpy(((char *) es) + EXT4_S_ERR_START,
5455                                save, EXT4_S_ERR_LEN);
5456                 kfree(save);
5457         }
5458
5459         if (err) {
5460                 ext4_msg(sb, KERN_ERR, "error loading journal");
5461                 goto err_out;
5462         }
5463
5464         EXT4_SB(sb)->s_journal = journal;
5465         err = ext4_clear_journal_err(sb, es);
5466         if (err) {
5467                 EXT4_SB(sb)->s_journal = NULL;
5468                 jbd2_journal_destroy(journal);
5469                 return err;
5470         }
5471
5472         if (!really_read_only && journal_devnum &&
5473             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
5474                 es->s_journal_dev = cpu_to_le32(journal_devnum);
5475
5476                 /* Make sure we flush the recovery flag to disk. */
5477                 ext4_commit_super(sb, 1);
5478         }
5479
5480         return 0;
5481
5482 err_out:
5483         jbd2_journal_destroy(journal);
5484         return err;
5485 }
5486
5487 static int ext4_commit_super(struct super_block *sb, int sync)
5488 {
5489         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
5490         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
5491         int error = 0;
5492
5493         if (!sbh || block_device_ejected(sb))
5494                 return error;
5495
5496         /*
5497          * If the file system is mounted read-only, don't update the
5498          * superblock write time.  This avoids updating the superblock
5499          * write time when we are mounting the root file system
5500          * read/only but we need to replay the journal; at that point,
5501          * for people who are east of GMT and who make their clock
5502          * tick in localtime for Windows bug-for-bug compatibility,
5503          * the clock is set in the future, and this will cause e2fsck
5504          * to complain and force a full file system check.
5505          */
5506         if (!(sb->s_flags & SB_RDONLY))
5507                 ext4_update_tstamp(es, s_wtime);
5508         if (sb->s_bdev->bd_part)
5509                 es->s_kbytes_written =
5510                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
5511                             ((part_stat_read(sb->s_bdev->bd_part,
5512                                              sectors[STAT_WRITE]) -
5513                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
5514         else
5515                 es->s_kbytes_written =
5516                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
5517         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
5518                 ext4_free_blocks_count_set(es,
5519                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
5520                                 &EXT4_SB(sb)->s_freeclusters_counter)));
5521         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
5522                 es->s_free_inodes_count =
5523                         cpu_to_le32(percpu_counter_sum_positive(
5524                                 &EXT4_SB(sb)->s_freeinodes_counter));
5525         BUFFER_TRACE(sbh, "marking dirty");
5526         ext4_superblock_csum_set(sb);
5527         if (sync)
5528                 lock_buffer(sbh);
5529         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
5530                 /*
5531                  * Oh, dear.  A previous attempt to write the
5532                  * superblock failed.  This could happen because the
5533                  * USB device was yanked out.  Or it could happen to
5534                  * be a transient write error and maybe the block will
5535                  * be remapped.  Nothing we can do but to retry the
5536                  * write and hope for the best.
5537                  */
5538                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
5539                        "superblock detected");
5540                 clear_buffer_write_io_error(sbh);
5541                 set_buffer_uptodate(sbh);
5542         }
5543         mark_buffer_dirty(sbh);
5544         if (sync) {
5545                 unlock_buffer(sbh);
5546                 error = __sync_dirty_buffer(sbh,
5547                         REQ_SYNC | (test_opt(sb, BARRIER) ? REQ_FUA : 0));
5548                 if (buffer_write_io_error(sbh)) {
5549                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
5550                                "superblock");
5551                         clear_buffer_write_io_error(sbh);
5552                         set_buffer_uptodate(sbh);
5553                 }
5554         }
5555         return error;
5556 }
5557
5558 /*
5559  * Have we just finished recovery?  If so, and if we are mounting (or
5560  * remounting) the filesystem readonly, then we will end up with a
5561  * consistent fs on disk.  Record that fact.
5562  */
5563 static int ext4_mark_recovery_complete(struct super_block *sb,
5564                                        struct ext4_super_block *es)
5565 {
5566         int err;
5567         journal_t *journal = EXT4_SB(sb)->s_journal;
5568
5569         if (!ext4_has_feature_journal(sb)) {
5570                 if (journal != NULL) {
5571                         ext4_error(sb, "Journal got removed while the fs was "
5572                                    "mounted!");
5573                         return -EFSCORRUPTED;
5574                 }
5575                 return 0;
5576         }
5577         jbd2_journal_lock_updates(journal);
5578         err = jbd2_journal_flush(journal);
5579         if (err < 0)
5580                 goto out;
5581
5582         if (ext4_has_feature_journal_needs_recovery(sb) && sb_rdonly(sb)) {
5583                 ext4_clear_feature_journal_needs_recovery(sb);
5584                 ext4_commit_super(sb, 1);
5585         }
5586 out:
5587         jbd2_journal_unlock_updates(journal);
5588         return err;
5589 }
5590
5591 /*
5592  * If we are mounting (or read-write remounting) a filesystem whose journal
5593  * has recorded an error from a previous lifetime, move that error to the
5594  * main filesystem now.
5595  */
5596 static int ext4_clear_journal_err(struct super_block *sb,
5597                                    struct ext4_super_block *es)
5598 {
5599         journal_t *journal;
5600         int j_errno;
5601         const char *errstr;
5602
5603         if (!ext4_has_feature_journal(sb)) {
5604                 ext4_error(sb, "Journal got removed while the fs was mounted!");
5605                 return -EFSCORRUPTED;
5606         }
5607
5608         journal = EXT4_SB(sb)->s_journal;
5609
5610         /*
5611          * Now check for any error status which may have been recorded in the
5612          * journal by a prior ext4_error() or ext4_abort()
5613          */
5614
5615         j_errno = jbd2_journal_errno(journal);
5616         if (j_errno) {
5617                 char nbuf[16];
5618
5619                 errstr = ext4_decode_error(sb, j_errno, nbuf);
5620                 ext4_warning(sb, "Filesystem error recorded "
5621                              "from previous mount: %s", errstr);
5622                 ext4_warning(sb, "Marking fs in need of filesystem check.");
5623
5624                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
5625                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
5626                 ext4_commit_super(sb, 1);
5627
5628                 jbd2_journal_clear_err(journal);
5629                 jbd2_journal_update_sb_errno(journal);
5630         }
5631         return 0;
5632 }
5633
5634 /*
5635  * Force the running and committing transactions to commit,
5636  * and wait on the commit.
5637  */
5638 int ext4_force_commit(struct super_block *sb)
5639 {
5640         journal_t *journal;
5641
5642         if (sb_rdonly(sb))
5643                 return 0;
5644
5645         journal = EXT4_SB(sb)->s_journal;
5646         return ext4_journal_force_commit(journal);
5647 }
5648
5649 static int ext4_sync_fs(struct super_block *sb, int wait)
5650 {
5651         int ret = 0;
5652         tid_t target;
5653         bool needs_barrier = false;
5654         struct ext4_sb_info *sbi = EXT4_SB(sb);
5655
5656         if (unlikely(ext4_forced_shutdown(sbi)))
5657                 return 0;
5658
5659         trace_ext4_sync_fs(sb, wait);
5660         flush_workqueue(sbi->rsv_conversion_wq);
5661         /*
5662          * Writeback quota in non-journalled quota case - journalled quota has
5663          * no dirty dquots
5664          */
5665         dquot_writeback_dquots(sb, -1);
5666         /*
5667          * Data writeback is possible w/o journal transaction, so barrier must
5668          * being sent at the end of the function. But we can skip it if
5669          * transaction_commit will do it for us.
5670          */
5671         if (sbi->s_journal) {
5672                 target = jbd2_get_latest_transaction(sbi->s_journal);
5673                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
5674                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
5675                         needs_barrier = true;
5676
5677                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
5678                         if (wait)
5679                                 ret = jbd2_log_wait_commit(sbi->s_journal,
5680                                                            target);
5681                 }
5682         } else if (wait && test_opt(sb, BARRIER))
5683                 needs_barrier = true;
5684         if (needs_barrier) {
5685                 int err;
5686                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL);
5687                 if (!ret)
5688                         ret = err;
5689         }
5690
5691         return ret;
5692 }
5693
5694 /*
5695  * LVM calls this function before a (read-only) snapshot is created.  This
5696  * gives us a chance to flush the journal completely and mark the fs clean.
5697  *
5698  * Note that only this function cannot bring a filesystem to be in a clean
5699  * state independently. It relies on upper layer to stop all data & metadata
5700  * modifications.
5701  */
5702 static int ext4_freeze(struct super_block *sb)
5703 {
5704         int error = 0;
5705         journal_t *journal;
5706
5707         if (sb_rdonly(sb))
5708                 return 0;
5709
5710         journal = EXT4_SB(sb)->s_journal;
5711
5712         if (journal) {
5713                 /* Now we set up the journal barrier. */
5714                 jbd2_journal_lock_updates(journal);
5715
5716                 /*
5717                  * Don't clear the needs_recovery flag if we failed to
5718                  * flush the journal.
5719                  */
5720                 error = jbd2_journal_flush(journal);
5721                 if (error < 0)
5722                         goto out;
5723
5724                 /* Journal blocked and flushed, clear needs_recovery flag. */
5725                 ext4_clear_feature_journal_needs_recovery(sb);
5726         }
5727
5728         error = ext4_commit_super(sb, 1);
5729 out:
5730         if (journal)
5731                 /* we rely on upper layer to stop further updates */
5732                 jbd2_journal_unlock_updates(journal);
5733         return error;
5734 }
5735
5736 /*
5737  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
5738  * flag here, even though the filesystem is not technically dirty yet.
5739  */
5740 static int ext4_unfreeze(struct super_block *sb)
5741 {
5742         if (sb_rdonly(sb) || ext4_forced_shutdown(EXT4_SB(sb)))
5743                 return 0;
5744
5745         if (EXT4_SB(sb)->s_journal) {
5746                 /* Reset the needs_recovery flag before the fs is unlocked. */
5747                 ext4_set_feature_journal_needs_recovery(sb);
5748         }
5749
5750         ext4_commit_super(sb, 1);
5751         return 0;
5752 }
5753
5754 /*
5755  * Structure to save mount options for ext4_remount's benefit
5756  */
5757 struct ext4_mount_options {
5758         unsigned long s_mount_opt;
5759         unsigned long s_mount_opt2;
5760         kuid_t s_resuid;
5761         kgid_t s_resgid;
5762         unsigned long s_commit_interval;
5763         u32 s_min_batch_time, s_max_batch_time;
5764 #ifdef CONFIG_QUOTA
5765         int s_jquota_fmt;
5766         char *s_qf_names[EXT4_MAXQUOTAS];
5767 #endif
5768 };
5769
5770 static int ext4_remount(struct super_block *sb, int *flags, char *data)
5771 {
5772         struct ext4_super_block *es;
5773         struct ext4_sb_info *sbi = EXT4_SB(sb);
5774         unsigned long old_sb_flags, vfs_flags;
5775         struct ext4_mount_options old_opts;
5776         int enable_quota = 0;
5777         ext4_group_t g;
5778         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
5779         int err = 0;
5780 #ifdef CONFIG_QUOTA
5781         int i, j;
5782         char *to_free[EXT4_MAXQUOTAS];
5783 #endif
5784         char *orig_data = kstrdup(data, GFP_KERNEL);
5785
5786         if (data && !orig_data)
5787                 return -ENOMEM;
5788
5789         /* Store the original options */
5790         old_sb_flags = sb->s_flags;
5791         old_opts.s_mount_opt = sbi->s_mount_opt;
5792         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
5793         old_opts.s_resuid = sbi->s_resuid;
5794         old_opts.s_resgid = sbi->s_resgid;
5795         old_opts.s_commit_interval = sbi->s_commit_interval;
5796         old_opts.s_min_batch_time = sbi->s_min_batch_time;
5797         old_opts.s_max_batch_time = sbi->s_max_batch_time;
5798 #ifdef CONFIG_QUOTA
5799         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
5800         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5801                 if (sbi->s_qf_names[i]) {
5802                         char *qf_name = get_qf_name(sb, sbi, i);
5803
5804                         old_opts.s_qf_names[i] = kstrdup(qf_name, GFP_KERNEL);
5805                         if (!old_opts.s_qf_names[i]) {
5806                                 for (j = 0; j < i; j++)
5807                                         kfree(old_opts.s_qf_names[j]);
5808                                 kfree(orig_data);
5809                                 return -ENOMEM;
5810                         }
5811                 } else
5812                         old_opts.s_qf_names[i] = NULL;
5813 #endif
5814         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5815                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5816
5817         /*
5818          * Some options can be enabled by ext4 and/or by VFS mount flag
5819          * either way we need to make sure it matches in both *flags and
5820          * s_flags. Copy those selected flags from *flags to s_flags
5821          */
5822         vfs_flags = SB_LAZYTIME | SB_I_VERSION;
5823         sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags);
5824
5825         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5826                 err = -EINVAL;
5827                 goto restore_opts;
5828         }
5829
5830         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5831             test_opt(sb, JOURNAL_CHECKSUM)) {
5832                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5833                          "during remount not supported; ignoring");
5834                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5835         }
5836
5837         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5838                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5839                         ext4_msg(sb, KERN_ERR, "can't mount with "
5840                                  "both data=journal and delalloc");
5841                         err = -EINVAL;
5842                         goto restore_opts;
5843                 }
5844                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5845                         ext4_msg(sb, KERN_ERR, "can't mount with "
5846                                  "both data=journal and dioread_nolock");
5847                         err = -EINVAL;
5848                         goto restore_opts;
5849                 }
5850         } else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA) {
5851                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
5852                         ext4_msg(sb, KERN_ERR, "can't mount with "
5853                                 "journal_async_commit in data=ordered mode");
5854                         err = -EINVAL;
5855                         goto restore_opts;
5856                 }
5857         }
5858
5859         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_NO_MBCACHE) {
5860                 ext4_msg(sb, KERN_ERR, "can't enable nombcache during remount");
5861                 err = -EINVAL;
5862                 goto restore_opts;
5863         }
5864
5865         if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED))
5866                 ext4_abort(sb, EXT4_ERR_ESHUTDOWN, "Abort forced by user");
5867
5868         sb->s_flags = (sb->s_flags & ~SB_POSIXACL) |
5869                 (test_opt(sb, POSIX_ACL) ? SB_POSIXACL : 0);
5870
5871         es = sbi->s_es;
5872
5873         if (sbi->s_journal) {
5874                 ext4_init_journal_params(sb, sbi->s_journal);
5875                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5876         }
5877
5878         if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) {
5879                 if (ext4_test_mount_flag(sb, EXT4_MF_FS_ABORTED)) {
5880                         err = -EROFS;
5881                         goto restore_opts;
5882                 }
5883
5884                 if (*flags & SB_RDONLY) {
5885                         err = sync_filesystem(sb);
5886                         if (err < 0)
5887                                 goto restore_opts;
5888                         err = dquot_suspend(sb, -1);
5889                         if (err < 0)
5890                                 goto restore_opts;
5891
5892                         /*
5893                          * First of all, the unconditional stuff we have to do
5894                          * to disable replay of the journal when we next remount
5895                          */
5896                         sb->s_flags |= SB_RDONLY;
5897
5898                         /*
5899                          * OK, test if we are remounting a valid rw partition
5900                          * readonly, and if so set the rdonly flag and then
5901                          * mark the partition as valid again.
5902                          */
5903                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5904                             (sbi->s_mount_state & EXT4_VALID_FS))
5905                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5906
5907                         if (sbi->s_journal) {
5908                                 /*
5909                                  * We let remount-ro finish even if marking fs
5910                                  * as clean failed...
5911                                  */
5912                                 ext4_mark_recovery_complete(sb, es);
5913                         }
5914                         if (sbi->s_mmp_tsk)
5915                                 kthread_stop(sbi->s_mmp_tsk);
5916                 } else {
5917                         /* Make sure we can mount this feature set readwrite */
5918                         if (ext4_has_feature_readonly(sb) ||
5919                             !ext4_feature_set_ok(sb, 0)) {
5920                                 err = -EROFS;
5921                                 goto restore_opts;
5922                         }
5923                         /*
5924                          * Make sure the group descriptor checksums
5925                          * are sane.  If they aren't, refuse to remount r/w.
5926                          */
5927                         for (g = 0; g < sbi->s_groups_count; g++) {
5928                                 struct ext4_group_desc *gdp =
5929                                         ext4_get_group_desc(sb, g, NULL);
5930
5931                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5932                                         ext4_msg(sb, KERN_ERR,
5933                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5934                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5935                                                le16_to_cpu(gdp->bg_checksum));
5936                                         err = -EFSBADCRC;
5937                                         goto restore_opts;
5938                                 }
5939                         }
5940
5941                         /*
5942                          * If we have an unprocessed orphan list hanging
5943                          * around from a previously readonly bdev mount,
5944                          * require a full umount/remount for now.
5945                          */
5946                         if (es->s_last_orphan) {
5947                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5948                                        "remount RDWR because of unprocessed "
5949                                        "orphan inode list.  Please "
5950                                        "umount/remount instead");
5951                                 err = -EINVAL;
5952                                 goto restore_opts;
5953                         }
5954
5955                         /*
5956                          * Mounting a RDONLY partition read-write, so reread
5957                          * and store the current valid flag.  (It may have
5958                          * been changed by e2fsck since we originally mounted
5959                          * the partition.)
5960                          */
5961                         if (sbi->s_journal) {
5962                                 err = ext4_clear_journal_err(sb, es);
5963                                 if (err)
5964                                         goto restore_opts;
5965                         }
5966                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5967
5968                         err = ext4_setup_super(sb, es, 0);
5969                         if (err)
5970                                 goto restore_opts;
5971
5972                         sb->s_flags &= ~SB_RDONLY;
5973                         if (ext4_has_feature_mmp(sb))
5974                                 if (ext4_multi_mount_protect(sb,
5975                                                 le64_to_cpu(es->s_mmp_block))) {
5976                                         err = -EROFS;
5977                                         goto restore_opts;
5978                                 }
5979                         enable_quota = 1;
5980                 }
5981         }
5982
5983         /*
5984          * Reinitialize lazy itable initialization thread based on
5985          * current settings
5986          */
5987         if (sb_rdonly(sb) || !test_opt(sb, INIT_INODE_TABLE))
5988                 ext4_unregister_li_request(sb);
5989         else {
5990                 ext4_group_t first_not_zeroed;
5991                 first_not_zeroed = ext4_has_uninit_itable(sb);
5992                 ext4_register_li_request(sb, first_not_zeroed);
5993         }
5994
5995         /*
5996          * Handle creation of system zone data early because it can fail.
5997          * Releasing of existing data is done when we are sure remount will
5998          * succeed.
5999          */
6000         if (test_opt(sb, BLOCK_VALIDITY) && !sbi->s_system_blks) {
6001                 err = ext4_setup_system_zone(sb);
6002                 if (err)
6003                         goto restore_opts;
6004         }
6005
6006         if (sbi->s_journal == NULL && !(old_sb_flags & SB_RDONLY)) {
6007                 err = ext4_commit_super(sb, 1);
6008                 if (err)
6009                         goto restore_opts;
6010         }
6011
6012 #ifdef CONFIG_QUOTA
6013         /* Release old quota file names */
6014         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6015                 kfree(old_opts.s_qf_names[i]);
6016         if (enable_quota) {
6017                 if (sb_any_quota_suspended(sb))
6018                         dquot_resume(sb, -1);
6019                 else if (ext4_has_feature_quota(sb)) {
6020                         err = ext4_enable_quotas(sb);
6021                         if (err)
6022                                 goto restore_opts;
6023                 }
6024         }
6025 #endif
6026         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6027                 ext4_release_system_zone(sb);
6028
6029         /*
6030          * Some options can be enabled by ext4 and/or by VFS mount flag
6031          * either way we need to make sure it matches in both *flags and
6032          * s_flags. Copy those selected flags from s_flags to *flags
6033          */
6034         *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags);
6035
6036         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
6037         kfree(orig_data);
6038         return 0;
6039
6040 restore_opts:
6041         sb->s_flags = old_sb_flags;
6042         sbi->s_mount_opt = old_opts.s_mount_opt;
6043         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
6044         sbi->s_resuid = old_opts.s_resuid;
6045         sbi->s_resgid = old_opts.s_resgid;
6046         sbi->s_commit_interval = old_opts.s_commit_interval;
6047         sbi->s_min_batch_time = old_opts.s_min_batch_time;
6048         sbi->s_max_batch_time = old_opts.s_max_batch_time;
6049         if (!test_opt(sb, BLOCK_VALIDITY) && sbi->s_system_blks)
6050                 ext4_release_system_zone(sb);
6051 #ifdef CONFIG_QUOTA
6052         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
6053         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
6054                 to_free[i] = get_qf_name(sb, sbi, i);
6055                 rcu_assign_pointer(sbi->s_qf_names[i], old_opts.s_qf_names[i]);
6056         }
6057         synchronize_rcu();
6058         for (i = 0; i < EXT4_MAXQUOTAS; i++)
6059                 kfree(to_free[i]);
6060 #endif
6061         kfree(orig_data);
6062         return err;
6063 }
6064
6065 #ifdef CONFIG_QUOTA
6066 static int ext4_statfs_project(struct super_block *sb,
6067                                kprojid_t projid, struct kstatfs *buf)
6068 {
6069         struct kqid qid;
6070         struct dquot *dquot;
6071         u64 limit;
6072         u64 curblock;
6073
6074         qid = make_kqid_projid(projid);
6075         dquot = dqget(sb, qid);
6076         if (IS_ERR(dquot))
6077                 return PTR_ERR(dquot);
6078         spin_lock(&dquot->dq_dqb_lock);
6079
6080         limit = min_not_zero(dquot->dq_dqb.dqb_bsoftlimit,
6081                              dquot->dq_dqb.dqb_bhardlimit);
6082         limit >>= sb->s_blocksize_bits;
6083
6084         if (limit && buf->f_blocks > limit) {
6085                 curblock = (dquot->dq_dqb.dqb_curspace +
6086                             dquot->dq_dqb.dqb_rsvspace) >> sb->s_blocksize_bits;
6087                 buf->f_blocks = limit;
6088                 buf->f_bfree = buf->f_bavail =
6089                         (buf->f_blocks > curblock) ?
6090                          (buf->f_blocks - curblock) : 0;
6091         }
6092
6093         limit = min_not_zero(dquot->dq_dqb.dqb_isoftlimit,
6094                              dquot->dq_dqb.dqb_ihardlimit);
6095         if (limit && buf->f_files > limit) {
6096                 buf->f_files = limit;
6097                 buf->f_ffree =
6098                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
6099                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
6100         }
6101
6102         spin_unlock(&dquot->dq_dqb_lock);
6103         dqput(dquot);
6104         return 0;
6105 }
6106 #endif
6107
6108 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
6109 {
6110         struct super_block *sb = dentry->d_sb;
6111         struct ext4_sb_info *sbi = EXT4_SB(sb);
6112         struct ext4_super_block *es = sbi->s_es;
6113         ext4_fsblk_t overhead = 0, resv_blocks;
6114         u64 fsid;
6115         s64 bfree;
6116         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
6117
6118         if (!test_opt(sb, MINIX_DF))
6119                 overhead = sbi->s_overhead;
6120
6121         buf->f_type = EXT4_SUPER_MAGIC;
6122         buf->f_bsize = sb->s_blocksize;
6123         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
6124         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
6125                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
6126         /* prevent underflow in case that few free space is available */
6127         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
6128         buf->f_bavail = buf->f_bfree -
6129                         (ext4_r_blocks_count(es) + resv_blocks);
6130         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
6131                 buf->f_bavail = 0;
6132         buf->f_files = le32_to_cpu(es->s_inodes_count);
6133         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
6134         buf->f_namelen = EXT4_NAME_LEN;
6135         fsid = le64_to_cpup((void *)es->s_uuid) ^
6136                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
6137         buf->f_fsid = u64_to_fsid(fsid);
6138
6139 #ifdef CONFIG_QUOTA
6140         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
6141             sb_has_quota_limits_enabled(sb, PRJQUOTA))
6142                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
6143 #endif
6144         return 0;
6145 }
6146
6147
6148 #ifdef CONFIG_QUOTA
6149
6150 /*
6151  * Helper functions so that transaction is started before we acquire dqio_sem
6152  * to keep correct lock ordering of transaction > dqio_sem
6153  */
6154 static inline struct inode *dquot_to_inode(struct dquot *dquot)
6155 {
6156         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
6157 }
6158
6159 static int ext4_write_dquot(struct dquot *dquot)
6160 {
6161         int ret, err;
6162         handle_t *handle;
6163         struct inode *inode;
6164
6165         inode = dquot_to_inode(dquot);
6166         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
6167                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
6168         if (IS_ERR(handle))
6169                 return PTR_ERR(handle);
6170         ret = dquot_commit(dquot);
6171         err = ext4_journal_stop(handle);
6172         if (!ret)
6173                 ret = err;
6174         return ret;
6175 }
6176
6177 static int ext4_acquire_dquot(struct dquot *dquot)
6178 {
6179         int ret, err;
6180         handle_t *handle;
6181
6182         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6183                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
6184         if (IS_ERR(handle))
6185                 return PTR_ERR(handle);
6186         ret = dquot_acquire(dquot);
6187         err = ext4_journal_stop(handle);
6188         if (!ret)
6189                 ret = err;
6190         return ret;
6191 }
6192
6193 static int ext4_release_dquot(struct dquot *dquot)
6194 {
6195         int ret, err;
6196         handle_t *handle;
6197
6198         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
6199                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
6200         if (IS_ERR(handle)) {
6201                 /* Release dquot anyway to avoid endless cycle in dqput() */
6202                 dquot_release(dquot);
6203                 return PTR_ERR(handle);
6204         }
6205         ret = dquot_release(dquot);
6206         err = ext4_journal_stop(handle);
6207         if (!ret)
6208                 ret = err;
6209         return ret;
6210 }
6211
6212 static int ext4_mark_dquot_dirty(struct dquot *dquot)
6213 {
6214         struct super_block *sb = dquot->dq_sb;
6215         struct ext4_sb_info *sbi = EXT4_SB(sb);
6216
6217         /* Are we journaling quotas? */
6218         if (ext4_has_feature_quota(sb) ||
6219             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
6220                 dquot_mark_dquot_dirty(dquot);
6221                 return ext4_write_dquot(dquot);
6222         } else {
6223                 return dquot_mark_dquot_dirty(dquot);
6224         }
6225 }
6226
6227 static int ext4_write_info(struct super_block *sb, int type)
6228 {
6229         int ret, err;
6230         handle_t *handle;
6231
6232         /* Data block + inode block */
6233         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
6234         if (IS_ERR(handle))
6235                 return PTR_ERR(handle);
6236         ret = dquot_commit_info(sb, type);
6237         err = ext4_journal_stop(handle);
6238         if (!ret)
6239                 ret = err;
6240         return ret;
6241 }
6242
6243 /*
6244  * Turn on quotas during mount time - we need to find
6245  * the quota file and such...
6246  */
6247 static int ext4_quota_on_mount(struct super_block *sb, int type)
6248 {
6249         return dquot_quota_on_mount(sb, get_qf_name(sb, EXT4_SB(sb), type),
6250                                         EXT4_SB(sb)->s_jquota_fmt, type);
6251 }
6252
6253 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
6254 {
6255         struct ext4_inode_info *ei = EXT4_I(inode);
6256
6257         /* The first argument of lockdep_set_subclass has to be
6258          * *exactly* the same as the argument to init_rwsem() --- in
6259          * this case, in init_once() --- or lockdep gets unhappy
6260          * because the name of the lock is set using the
6261          * stringification of the argument to init_rwsem().
6262          */
6263         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
6264         lockdep_set_subclass(&ei->i_data_sem, subclass);
6265 }
6266
6267 /*
6268  * Standard function to be called on quota_on
6269  */
6270 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
6271                          const struct path *path)
6272 {
6273         int err;
6274
6275         if (!test_opt(sb, QUOTA))
6276                 return -EINVAL;
6277
6278         /* Quotafile not on the same filesystem? */
6279         if (path->dentry->d_sb != sb)
6280                 return -EXDEV;
6281
6282         /* Quota already enabled for this file? */
6283         if (IS_NOQUOTA(d_inode(path->dentry)))
6284                 return -EBUSY;
6285
6286         /* Journaling quota? */
6287         if (EXT4_SB(sb)->s_qf_names[type]) {
6288                 /* Quotafile not in fs root? */
6289                 if (path->dentry->d_parent != sb->s_root)
6290                         ext4_msg(sb, KERN_WARNING,
6291                                 "Quota file not on filesystem root. "
6292                                 "Journaled quota will not work");
6293                 sb_dqopt(sb)->flags |= DQUOT_NOLIST_DIRTY;
6294         } else {
6295                 /*
6296                  * Clear the flag just in case mount options changed since
6297                  * last time.
6298                  */
6299                 sb_dqopt(sb)->flags &= ~DQUOT_NOLIST_DIRTY;
6300         }
6301
6302         /*
6303          * When we journal data on quota file, we have to flush journal to see
6304          * all updates to the file when we bypass pagecache...
6305          */
6306         if (EXT4_SB(sb)->s_journal &&
6307             ext4_should_journal_data(d_inode(path->dentry))) {
6308                 /*
6309                  * We don't need to lock updates but journal_flush() could
6310                  * otherwise be livelocked...
6311                  */
6312                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
6313                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
6314                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
6315                 if (err)
6316                         return err;
6317         }
6318
6319         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
6320         err = dquot_quota_on(sb, type, format_id, path);
6321         if (err) {
6322                 lockdep_set_quota_inode(path->dentry->d_inode,
6323                                              I_DATA_SEM_NORMAL);
6324         } else {
6325                 struct inode *inode = d_inode(path->dentry);
6326                 handle_t *handle;
6327
6328                 /*
6329                  * Set inode flags to prevent userspace from messing with quota
6330                  * files. If this fails, we return success anyway since quotas
6331                  * are already enabled and this is not a hard failure.
6332                  */
6333                 inode_lock(inode);
6334                 handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6335                 if (IS_ERR(handle))
6336                         goto unlock_inode;
6337                 EXT4_I(inode)->i_flags |= EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL;
6338                 inode_set_flags(inode, S_NOATIME | S_IMMUTABLE,
6339                                 S_NOATIME | S_IMMUTABLE);
6340                 err = ext4_mark_inode_dirty(handle, inode);
6341                 ext4_journal_stop(handle);
6342         unlock_inode:
6343                 inode_unlock(inode);
6344         }
6345         return err;
6346 }
6347
6348 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
6349                              unsigned int flags)
6350 {
6351         int err;
6352         struct inode *qf_inode;
6353         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6354                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6355                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6356                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6357         };
6358
6359         BUG_ON(!ext4_has_feature_quota(sb));
6360
6361         if (!qf_inums[type])
6362                 return -EPERM;
6363
6364         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
6365         if (IS_ERR(qf_inode)) {
6366                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
6367                 return PTR_ERR(qf_inode);
6368         }
6369
6370         /* Don't account quota for quota files to avoid recursion */
6371         qf_inode->i_flags |= S_NOQUOTA;
6372         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
6373         err = dquot_load_quota_inode(qf_inode, type, format_id, flags);
6374         if (err)
6375                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
6376         iput(qf_inode);
6377
6378         return err;
6379 }
6380
6381 /* Enable usage tracking for all quota types. */
6382 static int ext4_enable_quotas(struct super_block *sb)
6383 {
6384         int type, err = 0;
6385         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
6386                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
6387                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
6388                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
6389         };
6390         bool quota_mopt[EXT4_MAXQUOTAS] = {
6391                 test_opt(sb, USRQUOTA),
6392                 test_opt(sb, GRPQUOTA),
6393                 test_opt(sb, PRJQUOTA),
6394         };
6395
6396         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE | DQUOT_NOLIST_DIRTY;
6397         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
6398                 if (qf_inums[type]) {
6399                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
6400                                 DQUOT_USAGE_ENABLED |
6401                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
6402                         if (err) {
6403                                 ext4_warning(sb,
6404                                         "Failed to enable quota tracking "
6405                                         "(type=%d, err=%d). Please run "
6406                                         "e2fsck to fix.", type, err);
6407                                 for (type--; type >= 0; type--)
6408                                         dquot_quota_off(sb, type);
6409
6410                                 return err;
6411                         }
6412                 }
6413         }
6414         return 0;
6415 }
6416
6417 static int ext4_quota_off(struct super_block *sb, int type)
6418 {
6419         struct inode *inode = sb_dqopt(sb)->files[type];
6420         handle_t *handle;
6421         int err;
6422
6423         /* Force all delayed allocation blocks to be allocated.
6424          * Caller already holds s_umount sem */
6425         if (test_opt(sb, DELALLOC))
6426                 sync_filesystem(sb);
6427
6428         if (!inode || !igrab(inode))
6429                 goto out;
6430
6431         err = dquot_quota_off(sb, type);
6432         if (err || ext4_has_feature_quota(sb))
6433                 goto out_put;
6434
6435         inode_lock(inode);
6436         /*
6437          * Update modification times of quota files when userspace can
6438          * start looking at them. If we fail, we return success anyway since
6439          * this is not a hard failure and quotas are already disabled.
6440          */
6441         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
6442         if (IS_ERR(handle)) {
6443                 err = PTR_ERR(handle);
6444                 goto out_unlock;
6445         }
6446         EXT4_I(inode)->i_flags &= ~(EXT4_NOATIME_FL | EXT4_IMMUTABLE_FL);
6447         inode_set_flags(inode, 0, S_NOATIME | S_IMMUTABLE);
6448         inode->i_mtime = inode->i_ctime = current_time(inode);
6449         err = ext4_mark_inode_dirty(handle, inode);
6450         ext4_journal_stop(handle);
6451 out_unlock:
6452         inode_unlock(inode);
6453 out_put:
6454         lockdep_set_quota_inode(inode, I_DATA_SEM_NORMAL);
6455         iput(inode);
6456         return err;
6457 out:
6458         return dquot_quota_off(sb, type);
6459 }
6460
6461 /* Read data from quotafile - avoid pagecache and such because we cannot afford
6462  * acquiring the locks... As quota files are never truncated and quota code
6463  * itself serializes the operations (and no one else should touch the files)
6464  * we don't have to be afraid of races */
6465 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
6466                                size_t len, loff_t off)
6467 {
6468         struct inode *inode = sb_dqopt(sb)->files[type];
6469         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6470         int offset = off & (sb->s_blocksize - 1);
6471         int tocopy;
6472         size_t toread;
6473         struct buffer_head *bh;
6474         loff_t i_size = i_size_read(inode);
6475
6476         if (off > i_size)
6477                 return 0;
6478         if (off+len > i_size)
6479                 len = i_size-off;
6480         toread = len;
6481         while (toread > 0) {
6482                 tocopy = sb->s_blocksize - offset < toread ?
6483                                 sb->s_blocksize - offset : toread;
6484                 bh = ext4_bread(NULL, inode, blk, 0);
6485                 if (IS_ERR(bh))
6486                         return PTR_ERR(bh);
6487                 if (!bh)        /* A hole? */
6488                         memset(data, 0, tocopy);
6489                 else
6490                         memcpy(data, bh->b_data+offset, tocopy);
6491                 brelse(bh);
6492                 offset = 0;
6493                 toread -= tocopy;
6494                 data += tocopy;
6495                 blk++;
6496         }
6497         return len;
6498 }
6499
6500 /* Write to quotafile (we know the transaction is already started and has
6501  * enough credits) */
6502 static ssize_t ext4_quota_write(struct super_block *sb, int type,
6503                                 const char *data, size_t len, loff_t off)
6504 {
6505         struct inode *inode = sb_dqopt(sb)->files[type];
6506         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
6507         int err = 0, err2 = 0, offset = off & (sb->s_blocksize - 1);
6508         int retries = 0;
6509         struct buffer_head *bh;
6510         handle_t *handle = journal_current_handle();
6511
6512         if (EXT4_SB(sb)->s_journal && !handle) {
6513                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6514                         " cancelled because transaction is not started",
6515                         (unsigned long long)off, (unsigned long long)len);
6516                 return -EIO;
6517         }
6518         /*
6519          * Since we account only one data block in transaction credits,
6520          * then it is impossible to cross a block boundary.
6521          */
6522         if (sb->s_blocksize - offset < len) {
6523                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
6524                         " cancelled because not block aligned",
6525                         (unsigned long long)off, (unsigned long long)len);
6526                 return -EIO;
6527         }
6528
6529         do {
6530                 bh = ext4_bread(handle, inode, blk,
6531                                 EXT4_GET_BLOCKS_CREATE |
6532                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
6533         } while (PTR_ERR(bh) == -ENOSPC &&
6534                  ext4_should_retry_alloc(inode->i_sb, &retries));
6535         if (IS_ERR(bh))
6536                 return PTR_ERR(bh);
6537         if (!bh)
6538                 goto out;
6539         BUFFER_TRACE(bh, "get write access");
6540         err = ext4_journal_get_write_access(handle, bh);
6541         if (err) {
6542                 brelse(bh);
6543                 return err;
6544         }
6545         lock_buffer(bh);
6546         memcpy(bh->b_data+offset, data, len);
6547         flush_dcache_page(bh->b_page);
6548         unlock_buffer(bh);
6549         err = ext4_handle_dirty_metadata(handle, NULL, bh);
6550         brelse(bh);
6551 out:
6552         if (inode->i_size < off + len) {
6553                 i_size_write(inode, off + len);
6554                 EXT4_I(inode)->i_disksize = inode->i_size;
6555                 err2 = ext4_mark_inode_dirty(handle, inode);
6556                 if (unlikely(err2 && !err))
6557                         err = err2;
6558         }
6559         return err ? err : len;
6560 }
6561 #endif
6562
6563 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
6564                        const char *dev_name, void *data)
6565 {
6566         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
6567 }
6568
6569 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
6570 static inline void register_as_ext2(void)
6571 {
6572         int err = register_filesystem(&ext2_fs_type);
6573         if (err)
6574                 printk(KERN_WARNING
6575                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
6576 }
6577
6578 static inline void unregister_as_ext2(void)
6579 {
6580         unregister_filesystem(&ext2_fs_type);
6581 }
6582
6583 static inline int ext2_feature_set_ok(struct super_block *sb)
6584 {
6585         if (ext4_has_unknown_ext2_incompat_features(sb))
6586                 return 0;
6587         if (sb_rdonly(sb))
6588                 return 1;
6589         if (ext4_has_unknown_ext2_ro_compat_features(sb))
6590                 return 0;
6591         return 1;
6592 }
6593 #else
6594 static inline void register_as_ext2(void) { }
6595 static inline void unregister_as_ext2(void) { }
6596 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
6597 #endif
6598
6599 static inline void register_as_ext3(void)
6600 {
6601         int err = register_filesystem(&ext3_fs_type);
6602         if (err)
6603                 printk(KERN_WARNING
6604                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
6605 }
6606
6607 static inline void unregister_as_ext3(void)
6608 {
6609         unregister_filesystem(&ext3_fs_type);
6610 }
6611
6612 static inline int ext3_feature_set_ok(struct super_block *sb)
6613 {
6614         if (ext4_has_unknown_ext3_incompat_features(sb))
6615                 return 0;
6616         if (!ext4_has_feature_journal(sb))
6617                 return 0;
6618         if (sb_rdonly(sb))
6619                 return 1;
6620         if (ext4_has_unknown_ext3_ro_compat_features(sb))
6621                 return 0;
6622         return 1;
6623 }
6624
6625 static struct file_system_type ext4_fs_type = {
6626         .owner          = THIS_MODULE,
6627         .name           = "ext4",
6628         .mount          = ext4_mount,
6629         .kill_sb        = kill_block_super,
6630         .fs_flags       = FS_REQUIRES_DEV,
6631 };
6632 MODULE_ALIAS_FS("ext4");
6633
6634 /* Shared across all ext4 file systems */
6635 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
6636
6637 static int __init ext4_init_fs(void)
6638 {
6639         int i, err;
6640
6641         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
6642         ext4_li_info = NULL;
6643         mutex_init(&ext4_li_mtx);
6644
6645         /* Build-time check for flags consistency */
6646         ext4_check_flag_values();
6647
6648         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
6649                 init_waitqueue_head(&ext4__ioend_wq[i]);
6650
6651         err = ext4_init_es();
6652         if (err)
6653                 return err;
6654
6655         err = ext4_init_pending();
6656         if (err)
6657                 goto out7;
6658
6659         err = ext4_init_post_read_processing();
6660         if (err)
6661                 goto out6;
6662
6663         err = ext4_init_pageio();
6664         if (err)
6665                 goto out5;
6666
6667         err = ext4_init_system_zone();
6668         if (err)
6669                 goto out4;
6670
6671         err = ext4_init_sysfs();
6672         if (err)
6673                 goto out3;
6674
6675         err = ext4_init_mballoc();
6676         if (err)
6677                 goto out2;
6678         err = init_inodecache();
6679         if (err)
6680                 goto out1;
6681
6682         err = ext4_fc_init_dentry_cache();
6683         if (err)
6684                 goto out05;
6685
6686         register_as_ext3();
6687         register_as_ext2();
6688         err = register_filesystem(&ext4_fs_type);
6689         if (err)
6690                 goto out;
6691
6692         return 0;
6693 out:
6694         unregister_as_ext2();
6695         unregister_as_ext3();
6696 out05:
6697         destroy_inodecache();
6698 out1:
6699         ext4_exit_mballoc();
6700 out2:
6701         ext4_exit_sysfs();
6702 out3:
6703         ext4_exit_system_zone();
6704 out4:
6705         ext4_exit_pageio();
6706 out5:
6707         ext4_exit_post_read_processing();
6708 out6:
6709         ext4_exit_pending();
6710 out7:
6711         ext4_exit_es();
6712
6713         return err;
6714 }
6715
6716 static void __exit ext4_exit_fs(void)
6717 {
6718         ext4_destroy_lazyinit_thread();
6719         unregister_as_ext2();
6720         unregister_as_ext3();
6721         unregister_filesystem(&ext4_fs_type);
6722         destroy_inodecache();
6723         ext4_exit_mballoc();
6724         ext4_exit_sysfs();
6725         ext4_exit_system_zone();
6726         ext4_exit_pageio();
6727         ext4_exit_post_read_processing();
6728         ext4_exit_es();
6729         ext4_exit_pending();
6730 }
6731
6732 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
6733 MODULE_DESCRIPTION("Fourth Extended Filesystem");
6734 MODULE_LICENSE("GPL");
6735 MODULE_SOFTDEP("pre: crc32c");
6736 module_init(ext4_init_fs)
6737 module_exit(ext4_exit_fs)