Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[sfrench/cifs-2.6.git] / fs / ext4 / super.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/ext4/super.c
4  *
5  * Copyright (C) 1992, 1993, 1994, 1995
6  * Remy Card (card@masi.ibp.fr)
7  * Laboratoire MASI - Institut Blaise Pascal
8  * Universite Pierre et Marie Curie (Paris VI)
9  *
10  *  from
11  *
12  *  linux/fs/minix/inode.c
13  *
14  *  Copyright (C) 1991, 1992  Linus Torvalds
15  *
16  *  Big-endian to little-endian byte-swapping/bitmaps by
17  *        David S. Miller (davem@caip.rutgers.edu), 1995
18  */
19
20 #include <linux/module.h>
21 #include <linux/string.h>
22 #include <linux/fs.h>
23 #include <linux/time.h>
24 #include <linux/vmalloc.h>
25 #include <linux/slab.h>
26 #include <linux/init.h>
27 #include <linux/blkdev.h>
28 #include <linux/backing-dev.h>
29 #include <linux/parser.h>
30 #include <linux/buffer_head.h>
31 #include <linux/exportfs.h>
32 #include <linux/vfs.h>
33 #include <linux/random.h>
34 #include <linux/mount.h>
35 #include <linux/namei.h>
36 #include <linux/quotaops.h>
37 #include <linux/seq_file.h>
38 #include <linux/ctype.h>
39 #include <linux/log2.h>
40 #include <linux/crc16.h>
41 #include <linux/dax.h>
42 #include <linux/cleancache.h>
43 #include <linux/uaccess.h>
44 #include <linux/iversion.h>
45
46 #include <linux/kthread.h>
47 #include <linux/freezer.h>
48
49 #include "ext4.h"
50 #include "ext4_extents.h"       /* Needed for trace points definition */
51 #include "ext4_jbd2.h"
52 #include "xattr.h"
53 #include "acl.h"
54 #include "mballoc.h"
55 #include "fsmap.h"
56
57 #define CREATE_TRACE_POINTS
58 #include <trace/events/ext4.h>
59
60 static struct ext4_lazy_init *ext4_li_info;
61 static struct mutex ext4_li_mtx;
62 static struct ratelimit_state ext4_mount_msg_ratelimit;
63
64 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
65                              unsigned long journal_devnum);
66 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
67 static int ext4_commit_super(struct super_block *sb, int sync);
68 static void ext4_mark_recovery_complete(struct super_block *sb,
69                                         struct ext4_super_block *es);
70 static void ext4_clear_journal_err(struct super_block *sb,
71                                    struct ext4_super_block *es);
72 static int ext4_sync_fs(struct super_block *sb, int wait);
73 static int ext4_remount(struct super_block *sb, int *flags, char *data);
74 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
75 static int ext4_unfreeze(struct super_block *sb);
76 static int ext4_freeze(struct super_block *sb);
77 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
78                        const char *dev_name, void *data);
79 static inline int ext2_feature_set_ok(struct super_block *sb);
80 static inline int ext3_feature_set_ok(struct super_block *sb);
81 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
82 static void ext4_destroy_lazyinit_thread(void);
83 static void ext4_unregister_li_request(struct super_block *sb);
84 static void ext4_clear_request_list(void);
85 static struct inode *ext4_get_journal_inode(struct super_block *sb,
86                                             unsigned int journal_inum);
87
88 /*
89  * Lock ordering
90  *
91  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
92  * i_mmap_rwsem (inode->i_mmap_rwsem)!
93  *
94  * page fault path:
95  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
96  *   page lock -> i_data_sem (rw)
97  *
98  * buffered write path:
99  * sb_start_write -> i_mutex -> mmap_sem
100  * sb_start_write -> i_mutex -> transaction start -> page lock ->
101  *   i_data_sem (rw)
102  *
103  * truncate:
104  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> i_mmap_rwsem (w) -> page lock
105  * sb_start_write -> i_mutex -> i_mmap_sem (w) -> transaction start ->
106  *   i_data_sem (rw)
107  *
108  * direct IO:
109  * sb_start_write -> i_mutex -> mmap_sem
110  * sb_start_write -> i_mutex -> transaction start -> i_data_sem (rw)
111  *
112  * writepages:
113  * transaction start -> page lock(s) -> i_data_sem (rw)
114  */
115
116 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
117 static struct file_system_type ext2_fs_type = {
118         .owner          = THIS_MODULE,
119         .name           = "ext2",
120         .mount          = ext4_mount,
121         .kill_sb        = kill_block_super,
122         .fs_flags       = FS_REQUIRES_DEV,
123 };
124 MODULE_ALIAS_FS("ext2");
125 MODULE_ALIAS("ext2");
126 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
127 #else
128 #define IS_EXT2_SB(sb) (0)
129 #endif
130
131
132 static struct file_system_type ext3_fs_type = {
133         .owner          = THIS_MODULE,
134         .name           = "ext3",
135         .mount          = ext4_mount,
136         .kill_sb        = kill_block_super,
137         .fs_flags       = FS_REQUIRES_DEV,
138 };
139 MODULE_ALIAS_FS("ext3");
140 MODULE_ALIAS("ext3");
141 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
142
143 static int ext4_verify_csum_type(struct super_block *sb,
144                                  struct ext4_super_block *es)
145 {
146         if (!ext4_has_feature_metadata_csum(sb))
147                 return 1;
148
149         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
150 }
151
152 static __le32 ext4_superblock_csum(struct super_block *sb,
153                                    struct ext4_super_block *es)
154 {
155         struct ext4_sb_info *sbi = EXT4_SB(sb);
156         int offset = offsetof(struct ext4_super_block, s_checksum);
157         __u32 csum;
158
159         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
160
161         return cpu_to_le32(csum);
162 }
163
164 static int ext4_superblock_csum_verify(struct super_block *sb,
165                                        struct ext4_super_block *es)
166 {
167         if (!ext4_has_metadata_csum(sb))
168                 return 1;
169
170         return es->s_checksum == ext4_superblock_csum(sb, es);
171 }
172
173 void ext4_superblock_csum_set(struct super_block *sb)
174 {
175         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
176
177         if (!ext4_has_metadata_csum(sb))
178                 return;
179
180         es->s_checksum = ext4_superblock_csum(sb, es);
181 }
182
183 void *ext4_kvmalloc(size_t size, gfp_t flags)
184 {
185         void *ret;
186
187         ret = kmalloc(size, flags | __GFP_NOWARN);
188         if (!ret)
189                 ret = __vmalloc(size, flags, PAGE_KERNEL);
190         return ret;
191 }
192
193 void *ext4_kvzalloc(size_t size, gfp_t flags)
194 {
195         void *ret;
196
197         ret = kzalloc(size, flags | __GFP_NOWARN);
198         if (!ret)
199                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
200         return ret;
201 }
202
203 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
204                                struct ext4_group_desc *bg)
205 {
206         return le32_to_cpu(bg->bg_block_bitmap_lo) |
207                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
208                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
209 }
210
211 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
212                                struct ext4_group_desc *bg)
213 {
214         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
215                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
216                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
217 }
218
219 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
220                               struct ext4_group_desc *bg)
221 {
222         return le32_to_cpu(bg->bg_inode_table_lo) |
223                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
224                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
225 }
226
227 __u32 ext4_free_group_clusters(struct super_block *sb,
228                                struct ext4_group_desc *bg)
229 {
230         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
231                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
232                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
233 }
234
235 __u32 ext4_free_inodes_count(struct super_block *sb,
236                               struct ext4_group_desc *bg)
237 {
238         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
239                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
240                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
241 }
242
243 __u32 ext4_used_dirs_count(struct super_block *sb,
244                               struct ext4_group_desc *bg)
245 {
246         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
247                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
248                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
249 }
250
251 __u32 ext4_itable_unused_count(struct super_block *sb,
252                               struct ext4_group_desc *bg)
253 {
254         return le16_to_cpu(bg->bg_itable_unused_lo) |
255                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
256                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
257 }
258
259 void ext4_block_bitmap_set(struct super_block *sb,
260                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
261 {
262         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
263         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
264                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
265 }
266
267 void ext4_inode_bitmap_set(struct super_block *sb,
268                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
269 {
270         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
271         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
272                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
273 }
274
275 void ext4_inode_table_set(struct super_block *sb,
276                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
277 {
278         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
279         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
280                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
281 }
282
283 void ext4_free_group_clusters_set(struct super_block *sb,
284                                   struct ext4_group_desc *bg, __u32 count)
285 {
286         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
287         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
288                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
289 }
290
291 void ext4_free_inodes_set(struct super_block *sb,
292                           struct ext4_group_desc *bg, __u32 count)
293 {
294         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
295         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
296                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
297 }
298
299 void ext4_used_dirs_set(struct super_block *sb,
300                           struct ext4_group_desc *bg, __u32 count)
301 {
302         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
303         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
304                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
305 }
306
307 void ext4_itable_unused_set(struct super_block *sb,
308                           struct ext4_group_desc *bg, __u32 count)
309 {
310         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
311         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
312                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
313 }
314
315 static void __ext4_update_tstamp(__le32 *lo, __u8 *hi)
316 {
317         time64_t now = ktime_get_real_seconds();
318
319         now = clamp_val(now, 0, (1ull << 40) - 1);
320
321         *lo = cpu_to_le32(lower_32_bits(now));
322         *hi = upper_32_bits(now);
323 }
324
325 static time64_t __ext4_get_tstamp(__le32 *lo, __u8 *hi)
326 {
327         return ((time64_t)(*hi) << 32) + le32_to_cpu(*lo);
328 }
329 #define ext4_update_tstamp(es, tstamp) \
330         __ext4_update_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
331 #define ext4_get_tstamp(es, tstamp) \
332         __ext4_get_tstamp(&(es)->tstamp, &(es)->tstamp ## _hi)
333
334 static void __save_error_info(struct super_block *sb, const char *func,
335                             unsigned int line)
336 {
337         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
338
339         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
340         if (bdev_read_only(sb->s_bdev))
341                 return;
342         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
343         ext4_update_tstamp(es, s_last_error_time);
344         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
345         es->s_last_error_line = cpu_to_le32(line);
346         if (!es->s_first_error_time) {
347                 es->s_first_error_time = es->s_last_error_time;
348                 es->s_first_error_time_hi = es->s_last_error_time_hi;
349                 strncpy(es->s_first_error_func, func,
350                         sizeof(es->s_first_error_func));
351                 es->s_first_error_line = cpu_to_le32(line);
352                 es->s_first_error_ino = es->s_last_error_ino;
353                 es->s_first_error_block = es->s_last_error_block;
354         }
355         /*
356          * Start the daily error reporting function if it hasn't been
357          * started already
358          */
359         if (!es->s_error_count)
360                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
361         le32_add_cpu(&es->s_error_count, 1);
362 }
363
364 static void save_error_info(struct super_block *sb, const char *func,
365                             unsigned int line)
366 {
367         __save_error_info(sb, func, line);
368         ext4_commit_super(sb, 1);
369 }
370
371 /*
372  * The del_gendisk() function uninitializes the disk-specific data
373  * structures, including the bdi structure, without telling anyone
374  * else.  Once this happens, any attempt to call mark_buffer_dirty()
375  * (for example, by ext4_commit_super), will cause a kernel OOPS.
376  * This is a kludge to prevent these oops until we can put in a proper
377  * hook in del_gendisk() to inform the VFS and file system layers.
378  */
379 static int block_device_ejected(struct super_block *sb)
380 {
381         struct inode *bd_inode = sb->s_bdev->bd_inode;
382         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
383
384         return bdi->dev == NULL;
385 }
386
387 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
388 {
389         struct super_block              *sb = journal->j_private;
390         struct ext4_sb_info             *sbi = EXT4_SB(sb);
391         int                             error = is_journal_aborted(journal);
392         struct ext4_journal_cb_entry    *jce;
393
394         BUG_ON(txn->t_state == T_FINISHED);
395
396         ext4_process_freed_data(sb, txn->t_tid);
397
398         spin_lock(&sbi->s_md_lock);
399         while (!list_empty(&txn->t_private_list)) {
400                 jce = list_entry(txn->t_private_list.next,
401                                  struct ext4_journal_cb_entry, jce_list);
402                 list_del_init(&jce->jce_list);
403                 spin_unlock(&sbi->s_md_lock);
404                 jce->jce_func(sb, jce, error);
405                 spin_lock(&sbi->s_md_lock);
406         }
407         spin_unlock(&sbi->s_md_lock);
408 }
409
410 /* Deal with the reporting of failure conditions on a filesystem such as
411  * inconsistencies detected or read IO failures.
412  *
413  * On ext2, we can store the error state of the filesystem in the
414  * superblock.  That is not possible on ext4, because we may have other
415  * write ordering constraints on the superblock which prevent us from
416  * writing it out straight away; and given that the journal is about to
417  * be aborted, we can't rely on the current, or future, transactions to
418  * write out the superblock safely.
419  *
420  * We'll just use the jbd2_journal_abort() error code to record an error in
421  * the journal instead.  On recovery, the journal will complain about
422  * that error until we've noted it down and cleared it.
423  */
424
425 static void ext4_handle_error(struct super_block *sb)
426 {
427         if (test_opt(sb, WARN_ON_ERROR))
428                 WARN_ON_ONCE(1);
429
430         if (sb_rdonly(sb))
431                 return;
432
433         if (!test_opt(sb, ERRORS_CONT)) {
434                 journal_t *journal = EXT4_SB(sb)->s_journal;
435
436                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
437                 if (journal)
438                         jbd2_journal_abort(journal, -EIO);
439         }
440         if (test_opt(sb, ERRORS_RO)) {
441                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
442                 /*
443                  * Make sure updated value of ->s_mount_flags will be visible
444                  * before ->s_flags update
445                  */
446                 smp_wmb();
447                 sb->s_flags |= SB_RDONLY;
448         }
449         if (test_opt(sb, ERRORS_PANIC)) {
450                 if (EXT4_SB(sb)->s_journal &&
451                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
452                         return;
453                 panic("EXT4-fs (device %s): panic forced after error\n",
454                         sb->s_id);
455         }
456 }
457
458 #define ext4_error_ratelimit(sb)                                        \
459                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
460                              "EXT4-fs error")
461
462 void __ext4_error(struct super_block *sb, const char *function,
463                   unsigned int line, const char *fmt, ...)
464 {
465         struct va_format vaf;
466         va_list args;
467
468         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
469                 return;
470
471         trace_ext4_error(sb, function, line);
472         if (ext4_error_ratelimit(sb)) {
473                 va_start(args, fmt);
474                 vaf.fmt = fmt;
475                 vaf.va = &args;
476                 printk(KERN_CRIT
477                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
478                        sb->s_id, function, line, current->comm, &vaf);
479                 va_end(args);
480         }
481         save_error_info(sb, function, line);
482         ext4_handle_error(sb);
483 }
484
485 void __ext4_error_inode(struct inode *inode, const char *function,
486                         unsigned int line, ext4_fsblk_t block,
487                         const char *fmt, ...)
488 {
489         va_list args;
490         struct va_format vaf;
491         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
492
493         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
494                 return;
495
496         trace_ext4_error(inode->i_sb, function, line);
497         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
498         es->s_last_error_block = cpu_to_le64(block);
499         if (ext4_error_ratelimit(inode->i_sb)) {
500                 va_start(args, fmt);
501                 vaf.fmt = fmt;
502                 vaf.va = &args;
503                 if (block)
504                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
505                                "inode #%lu: block %llu: comm %s: %pV\n",
506                                inode->i_sb->s_id, function, line, inode->i_ino,
507                                block, current->comm, &vaf);
508                 else
509                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
510                                "inode #%lu: comm %s: %pV\n",
511                                inode->i_sb->s_id, function, line, inode->i_ino,
512                                current->comm, &vaf);
513                 va_end(args);
514         }
515         save_error_info(inode->i_sb, function, line);
516         ext4_handle_error(inode->i_sb);
517 }
518
519 void __ext4_error_file(struct file *file, const char *function,
520                        unsigned int line, ext4_fsblk_t block,
521                        const char *fmt, ...)
522 {
523         va_list args;
524         struct va_format vaf;
525         struct ext4_super_block *es;
526         struct inode *inode = file_inode(file);
527         char pathname[80], *path;
528
529         if (unlikely(ext4_forced_shutdown(EXT4_SB(inode->i_sb))))
530                 return;
531
532         trace_ext4_error(inode->i_sb, function, line);
533         es = EXT4_SB(inode->i_sb)->s_es;
534         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
535         if (ext4_error_ratelimit(inode->i_sb)) {
536                 path = file_path(file, pathname, sizeof(pathname));
537                 if (IS_ERR(path))
538                         path = "(unknown)";
539                 va_start(args, fmt);
540                 vaf.fmt = fmt;
541                 vaf.va = &args;
542                 if (block)
543                         printk(KERN_CRIT
544                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
545                                "block %llu: comm %s: path %s: %pV\n",
546                                inode->i_sb->s_id, function, line, inode->i_ino,
547                                block, current->comm, path, &vaf);
548                 else
549                         printk(KERN_CRIT
550                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
551                                "comm %s: path %s: %pV\n",
552                                inode->i_sb->s_id, function, line, inode->i_ino,
553                                current->comm, path, &vaf);
554                 va_end(args);
555         }
556         save_error_info(inode->i_sb, function, line);
557         ext4_handle_error(inode->i_sb);
558 }
559
560 const char *ext4_decode_error(struct super_block *sb, int errno,
561                               char nbuf[16])
562 {
563         char *errstr = NULL;
564
565         switch (errno) {
566         case -EFSCORRUPTED:
567                 errstr = "Corrupt filesystem";
568                 break;
569         case -EFSBADCRC:
570                 errstr = "Filesystem failed CRC";
571                 break;
572         case -EIO:
573                 errstr = "IO failure";
574                 break;
575         case -ENOMEM:
576                 errstr = "Out of memory";
577                 break;
578         case -EROFS:
579                 if (!sb || (EXT4_SB(sb)->s_journal &&
580                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
581                         errstr = "Journal has aborted";
582                 else
583                         errstr = "Readonly filesystem";
584                 break;
585         default:
586                 /* If the caller passed in an extra buffer for unknown
587                  * errors, textualise them now.  Else we just return
588                  * NULL. */
589                 if (nbuf) {
590                         /* Check for truncated error codes... */
591                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
592                                 errstr = nbuf;
593                 }
594                 break;
595         }
596
597         return errstr;
598 }
599
600 /* __ext4_std_error decodes expected errors from journaling functions
601  * automatically and invokes the appropriate error response.  */
602
603 void __ext4_std_error(struct super_block *sb, const char *function,
604                       unsigned int line, int errno)
605 {
606         char nbuf[16];
607         const char *errstr;
608
609         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
610                 return;
611
612         /* Special case: if the error is EROFS, and we're not already
613          * inside a transaction, then there's really no point in logging
614          * an error. */
615         if (errno == -EROFS && journal_current_handle() == NULL && sb_rdonly(sb))
616                 return;
617
618         if (ext4_error_ratelimit(sb)) {
619                 errstr = ext4_decode_error(sb, errno, nbuf);
620                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
621                        sb->s_id, function, line, errstr);
622         }
623
624         save_error_info(sb, function, line);
625         ext4_handle_error(sb);
626 }
627
628 /*
629  * ext4_abort is a much stronger failure handler than ext4_error.  The
630  * abort function may be used to deal with unrecoverable failures such
631  * as journal IO errors or ENOMEM at a critical moment in log management.
632  *
633  * We unconditionally force the filesystem into an ABORT|READONLY state,
634  * unless the error response on the fs has been set to panic in which
635  * case we take the easy way out and panic immediately.
636  */
637
638 void __ext4_abort(struct super_block *sb, const char *function,
639                 unsigned int line, const char *fmt, ...)
640 {
641         struct va_format vaf;
642         va_list args;
643
644         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
645                 return;
646
647         save_error_info(sb, function, line);
648         va_start(args, fmt);
649         vaf.fmt = fmt;
650         vaf.va = &args;
651         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
652                sb->s_id, function, line, &vaf);
653         va_end(args);
654
655         if (sb_rdonly(sb) == 0) {
656                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
657                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
658                 /*
659                  * Make sure updated value of ->s_mount_flags will be visible
660                  * before ->s_flags update
661                  */
662                 smp_wmb();
663                 sb->s_flags |= SB_RDONLY;
664                 if (EXT4_SB(sb)->s_journal)
665                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
666                 save_error_info(sb, function, line);
667         }
668         if (test_opt(sb, ERRORS_PANIC)) {
669                 if (EXT4_SB(sb)->s_journal &&
670                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
671                         return;
672                 panic("EXT4-fs panic from previous error\n");
673         }
674 }
675
676 void __ext4_msg(struct super_block *sb,
677                 const char *prefix, const char *fmt, ...)
678 {
679         struct va_format vaf;
680         va_list args;
681
682         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
683                 return;
684
685         va_start(args, fmt);
686         vaf.fmt = fmt;
687         vaf.va = &args;
688         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
689         va_end(args);
690 }
691
692 #define ext4_warning_ratelimit(sb)                                      \
693                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
694                              "EXT4-fs warning")
695
696 void __ext4_warning(struct super_block *sb, const char *function,
697                     unsigned int line, const char *fmt, ...)
698 {
699         struct va_format vaf;
700         va_list args;
701
702         if (!ext4_warning_ratelimit(sb))
703                 return;
704
705         va_start(args, fmt);
706         vaf.fmt = fmt;
707         vaf.va = &args;
708         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
709                sb->s_id, function, line, &vaf);
710         va_end(args);
711 }
712
713 void __ext4_warning_inode(const struct inode *inode, const char *function,
714                           unsigned int line, const char *fmt, ...)
715 {
716         struct va_format vaf;
717         va_list args;
718
719         if (!ext4_warning_ratelimit(inode->i_sb))
720                 return;
721
722         va_start(args, fmt);
723         vaf.fmt = fmt;
724         vaf.va = &args;
725         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
726                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
727                function, line, inode->i_ino, current->comm, &vaf);
728         va_end(args);
729 }
730
731 void __ext4_grp_locked_error(const char *function, unsigned int line,
732                              struct super_block *sb, ext4_group_t grp,
733                              unsigned long ino, ext4_fsblk_t block,
734                              const char *fmt, ...)
735 __releases(bitlock)
736 __acquires(bitlock)
737 {
738         struct va_format vaf;
739         va_list args;
740         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
741
742         if (unlikely(ext4_forced_shutdown(EXT4_SB(sb))))
743                 return;
744
745         trace_ext4_error(sb, function, line);
746         es->s_last_error_ino = cpu_to_le32(ino);
747         es->s_last_error_block = cpu_to_le64(block);
748         __save_error_info(sb, function, line);
749
750         if (ext4_error_ratelimit(sb)) {
751                 va_start(args, fmt);
752                 vaf.fmt = fmt;
753                 vaf.va = &args;
754                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
755                        sb->s_id, function, line, grp);
756                 if (ino)
757                         printk(KERN_CONT "inode %lu: ", ino);
758                 if (block)
759                         printk(KERN_CONT "block %llu:",
760                                (unsigned long long) block);
761                 printk(KERN_CONT "%pV\n", &vaf);
762                 va_end(args);
763         }
764
765         if (test_opt(sb, WARN_ON_ERROR))
766                 WARN_ON_ONCE(1);
767
768         if (test_opt(sb, ERRORS_CONT)) {
769                 ext4_commit_super(sb, 0);
770                 return;
771         }
772
773         ext4_unlock_group(sb, grp);
774         ext4_commit_super(sb, 1);
775         ext4_handle_error(sb);
776         /*
777          * We only get here in the ERRORS_RO case; relocking the group
778          * may be dangerous, but nothing bad will happen since the
779          * filesystem will have already been marked read/only and the
780          * journal has been aborted.  We return 1 as a hint to callers
781          * who might what to use the return value from
782          * ext4_grp_locked_error() to distinguish between the
783          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
784          * aggressively from the ext4 function in question, with a
785          * more appropriate error code.
786          */
787         ext4_lock_group(sb, grp);
788         return;
789 }
790
791 void ext4_mark_group_bitmap_corrupted(struct super_block *sb,
792                                      ext4_group_t group,
793                                      unsigned int flags)
794 {
795         struct ext4_sb_info *sbi = EXT4_SB(sb);
796         struct ext4_group_info *grp = ext4_get_group_info(sb, group);
797         struct ext4_group_desc *gdp = ext4_get_group_desc(sb, group, NULL);
798         int ret;
799
800         if (flags & EXT4_GROUP_INFO_BBITMAP_CORRUPT) {
801                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_BBITMAP_CORRUPT_BIT,
802                                             &grp->bb_state);
803                 if (!ret)
804                         percpu_counter_sub(&sbi->s_freeclusters_counter,
805                                            grp->bb_free);
806         }
807
808         if (flags & EXT4_GROUP_INFO_IBITMAP_CORRUPT) {
809                 ret = ext4_test_and_set_bit(EXT4_GROUP_INFO_IBITMAP_CORRUPT_BIT,
810                                             &grp->bb_state);
811                 if (!ret && gdp) {
812                         int count;
813
814                         count = ext4_free_inodes_count(sb, gdp);
815                         percpu_counter_sub(&sbi->s_freeinodes_counter,
816                                            count);
817                 }
818         }
819 }
820
821 void ext4_update_dynamic_rev(struct super_block *sb)
822 {
823         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
824
825         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
826                 return;
827
828         ext4_warning(sb,
829                      "updating to rev %d because of new feature flag, "
830                      "running e2fsck is recommended",
831                      EXT4_DYNAMIC_REV);
832
833         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
834         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
835         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
836         /* leave es->s_feature_*compat flags alone */
837         /* es->s_uuid will be set by e2fsck if empty */
838
839         /*
840          * The rest of the superblock fields should be zero, and if not it
841          * means they are likely already in use, so leave them alone.  We
842          * can leave it up to e2fsck to clean up any inconsistencies there.
843          */
844 }
845
846 /*
847  * Open the external journal device
848  */
849 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
850 {
851         struct block_device *bdev;
852         char b[BDEVNAME_SIZE];
853
854         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
855         if (IS_ERR(bdev))
856                 goto fail;
857         return bdev;
858
859 fail:
860         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
861                         __bdevname(dev, b), PTR_ERR(bdev));
862         return NULL;
863 }
864
865 /*
866  * Release the journal device
867  */
868 static void ext4_blkdev_put(struct block_device *bdev)
869 {
870         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
871 }
872
873 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
874 {
875         struct block_device *bdev;
876         bdev = sbi->journal_bdev;
877         if (bdev) {
878                 ext4_blkdev_put(bdev);
879                 sbi->journal_bdev = NULL;
880         }
881 }
882
883 static inline struct inode *orphan_list_entry(struct list_head *l)
884 {
885         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
886 }
887
888 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
889 {
890         struct list_head *l;
891
892         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
893                  le32_to_cpu(sbi->s_es->s_last_orphan));
894
895         printk(KERN_ERR "sb_info orphan list:\n");
896         list_for_each(l, &sbi->s_orphan) {
897                 struct inode *inode = orphan_list_entry(l);
898                 printk(KERN_ERR "  "
899                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
900                        inode->i_sb->s_id, inode->i_ino, inode,
901                        inode->i_mode, inode->i_nlink,
902                        NEXT_ORPHAN(inode));
903         }
904 }
905
906 #ifdef CONFIG_QUOTA
907 static int ext4_quota_off(struct super_block *sb, int type);
908
909 static inline void ext4_quota_off_umount(struct super_block *sb)
910 {
911         int type;
912
913         /* Use our quota_off function to clear inode flags etc. */
914         for (type = 0; type < EXT4_MAXQUOTAS; type++)
915                 ext4_quota_off(sb, type);
916 }
917
918 /*
919  * This is a helper function which is used in the mount/remount
920  * codepaths (which holds s_umount) to fetch the quota file name.
921  */
922 static inline char *get_qf_name(struct super_block *sb,
923                                 struct ext4_sb_info *sbi,
924                                 int type)
925 {
926         return rcu_dereference_protected(sbi->s_qf_names[type],
927                                          lockdep_is_held(&sb->s_umount));
928 }
929 #else
930 static inline void ext4_quota_off_umount(struct super_block *sb)
931 {
932 }
933 #endif
934
935 static void ext4_put_super(struct super_block *sb)
936 {
937         struct ext4_sb_info *sbi = EXT4_SB(sb);
938         struct ext4_super_block *es = sbi->s_es;
939         int aborted = 0;
940         int i, err;
941
942         ext4_unregister_li_request(sb);
943         ext4_quota_off_umount(sb);
944
945         destroy_workqueue(sbi->rsv_conversion_wq);
946
947         if (sbi->s_journal) {
948                 aborted = is_journal_aborted(sbi->s_journal);
949                 err = jbd2_journal_destroy(sbi->s_journal);
950                 sbi->s_journal = NULL;
951                 if ((err < 0) && !aborted)
952                         ext4_abort(sb, "Couldn't clean up the journal");
953         }
954
955         ext4_unregister_sysfs(sb);
956         ext4_es_unregister_shrinker(sbi);
957         del_timer_sync(&sbi->s_err_report);
958         ext4_release_system_zone(sb);
959         ext4_mb_release(sb);
960         ext4_ext_release(sb);
961
962         if (!sb_rdonly(sb) && !aborted) {
963                 ext4_clear_feature_journal_needs_recovery(sb);
964                 es->s_state = cpu_to_le16(sbi->s_mount_state);
965         }
966         if (!sb_rdonly(sb))
967                 ext4_commit_super(sb, 1);
968
969         for (i = 0; i < sbi->s_gdb_count; i++)
970                 brelse(sbi->s_group_desc[i]);
971         kvfree(sbi->s_group_desc);
972         kvfree(sbi->s_flex_groups);
973         percpu_counter_destroy(&sbi->s_freeclusters_counter);
974         percpu_counter_destroy(&sbi->s_freeinodes_counter);
975         percpu_counter_destroy(&sbi->s_dirs_counter);
976         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
977         percpu_free_rwsem(&sbi->s_journal_flag_rwsem);
978 #ifdef CONFIG_QUOTA
979         for (i = 0; i < EXT4_MAXQUOTAS; i++)
980                 kfree(get_qf_name(sb, sbi, i));
981 #endif
982
983         /* Debugging code just in case the in-memory inode orphan list
984          * isn't empty.  The on-disk one can be non-empty if we've
985          * detected an error and taken the fs readonly, but the
986          * in-memory list had better be clean by this point. */
987         if (!list_empty(&sbi->s_orphan))
988                 dump_orphan_list(sb, sbi);
989         J_ASSERT(list_empty(&sbi->s_orphan));
990
991         sync_blockdev(sb->s_bdev);
992         invalidate_bdev(sb->s_bdev);
993         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
994                 /*
995                  * Invalidate the journal device's buffers.  We don't want them
996                  * floating about in memory - the physical journal device may
997                  * hotswapped, and it breaks the `ro-after' testing code.
998                  */
999                 sync_blockdev(sbi->journal_bdev);
1000                 invalidate_bdev(sbi->journal_bdev);
1001                 ext4_blkdev_remove(sbi);
1002         }
1003         if (sbi->s_ea_inode_cache) {
1004                 ext4_xattr_destroy_cache(sbi->s_ea_inode_cache);
1005                 sbi->s_ea_inode_cache = NULL;
1006         }
1007         if (sbi->s_ea_block_cache) {
1008                 ext4_xattr_destroy_cache(sbi->s_ea_block_cache);
1009                 sbi->s_ea_block_cache = NULL;
1010         }
1011         if (sbi->s_mmp_tsk)
1012                 kthread_stop(sbi->s_mmp_tsk);
1013         brelse(sbi->s_sbh);
1014         sb->s_fs_info = NULL;
1015         /*
1016          * Now that we are completely done shutting down the
1017          * superblock, we need to actually destroy the kobject.
1018          */
1019         kobject_put(&sbi->s_kobj);
1020         wait_for_completion(&sbi->s_kobj_unregister);
1021         if (sbi->s_chksum_driver)
1022                 crypto_free_shash(sbi->s_chksum_driver);
1023         kfree(sbi->s_blockgroup_lock);
1024         fs_put_dax(sbi->s_daxdev);
1025         kfree(sbi);
1026 }
1027
1028 static struct kmem_cache *ext4_inode_cachep;
1029
1030 /*
1031  * Called inside transaction, so use GFP_NOFS
1032  */
1033 static struct inode *ext4_alloc_inode(struct super_block *sb)
1034 {
1035         struct ext4_inode_info *ei;
1036
1037         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
1038         if (!ei)
1039                 return NULL;
1040
1041         inode_set_iversion(&ei->vfs_inode, 1);
1042         spin_lock_init(&ei->i_raw_lock);
1043         INIT_LIST_HEAD(&ei->i_prealloc_list);
1044         spin_lock_init(&ei->i_prealloc_lock);
1045         ext4_es_init_tree(&ei->i_es_tree);
1046         rwlock_init(&ei->i_es_lock);
1047         INIT_LIST_HEAD(&ei->i_es_list);
1048         ei->i_es_all_nr = 0;
1049         ei->i_es_shk_nr = 0;
1050         ei->i_es_shrink_lblk = 0;
1051         ei->i_reserved_data_blocks = 0;
1052         ei->i_da_metadata_calc_len = 0;
1053         ei->i_da_metadata_calc_last_lblock = 0;
1054         spin_lock_init(&(ei->i_block_reservation_lock));
1055         ext4_init_pending_tree(&ei->i_pending_tree);
1056 #ifdef CONFIG_QUOTA
1057         ei->i_reserved_quota = 0;
1058         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
1059 #endif
1060         ei->jinode = NULL;
1061         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
1062         spin_lock_init(&ei->i_completed_io_lock);
1063         ei->i_sync_tid = 0;
1064         ei->i_datasync_tid = 0;
1065         atomic_set(&ei->i_unwritten, 0);
1066         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
1067         return &ei->vfs_inode;
1068 }
1069
1070 static int ext4_drop_inode(struct inode *inode)
1071 {
1072         int drop = generic_drop_inode(inode);
1073
1074         trace_ext4_drop_inode(inode, drop);
1075         return drop;
1076 }
1077
1078 static void ext4_i_callback(struct rcu_head *head)
1079 {
1080         struct inode *inode = container_of(head, struct inode, i_rcu);
1081         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
1082 }
1083
1084 static void ext4_destroy_inode(struct inode *inode)
1085 {
1086         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
1087                 ext4_msg(inode->i_sb, KERN_ERR,
1088                          "Inode %lu (%p): orphan list check failed!",
1089                          inode->i_ino, EXT4_I(inode));
1090                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
1091                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
1092                                 true);
1093                 dump_stack();
1094         }
1095         call_rcu(&inode->i_rcu, ext4_i_callback);
1096 }
1097
1098 static void init_once(void *foo)
1099 {
1100         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
1101
1102         INIT_LIST_HEAD(&ei->i_orphan);
1103         init_rwsem(&ei->xattr_sem);
1104         init_rwsem(&ei->i_data_sem);
1105         init_rwsem(&ei->i_mmap_sem);
1106         inode_init_once(&ei->vfs_inode);
1107 }
1108
1109 static int __init init_inodecache(void)
1110 {
1111         ext4_inode_cachep = kmem_cache_create_usercopy("ext4_inode_cache",
1112                                 sizeof(struct ext4_inode_info), 0,
1113                                 (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
1114                                         SLAB_ACCOUNT),
1115                                 offsetof(struct ext4_inode_info, i_data),
1116                                 sizeof_field(struct ext4_inode_info, i_data),
1117                                 init_once);
1118         if (ext4_inode_cachep == NULL)
1119                 return -ENOMEM;
1120         return 0;
1121 }
1122
1123 static void destroy_inodecache(void)
1124 {
1125         /*
1126          * Make sure all delayed rcu free inodes are flushed before we
1127          * destroy cache.
1128          */
1129         rcu_barrier();
1130         kmem_cache_destroy(ext4_inode_cachep);
1131 }
1132
1133 void ext4_clear_inode(struct inode *inode)
1134 {
1135         invalidate_inode_buffers(inode);
1136         clear_inode(inode);
1137         dquot_drop(inode);
1138         ext4_discard_preallocations(inode);
1139         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1140         if (EXT4_I(inode)->jinode) {
1141                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1142                                                EXT4_I(inode)->jinode);
1143                 jbd2_free_inode(EXT4_I(inode)->jinode);
1144                 EXT4_I(inode)->jinode = NULL;
1145         }
1146         fscrypt_put_encryption_info(inode);
1147 }
1148
1149 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1150                                         u64 ino, u32 generation)
1151 {
1152         struct inode *inode;
1153
1154         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
1155                 return ERR_PTR(-ESTALE);
1156         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
1157                 return ERR_PTR(-ESTALE);
1158
1159         /* iget isn't really right if the inode is currently unallocated!!
1160          *
1161          * ext4_read_inode will return a bad_inode if the inode had been
1162          * deleted, so we should be safe.
1163          *
1164          * Currently we don't know the generation for parent directory, so
1165          * a generation of 0 means "accept any"
1166          */
1167         inode = ext4_iget_normal(sb, ino);
1168         if (IS_ERR(inode))
1169                 return ERR_CAST(inode);
1170         if (generation && inode->i_generation != generation) {
1171                 iput(inode);
1172                 return ERR_PTR(-ESTALE);
1173         }
1174
1175         return inode;
1176 }
1177
1178 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1179                                         int fh_len, int fh_type)
1180 {
1181         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1182                                     ext4_nfs_get_inode);
1183 }
1184
1185 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1186                                         int fh_len, int fh_type)
1187 {
1188         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1189                                     ext4_nfs_get_inode);
1190 }
1191
1192 /*
1193  * Try to release metadata pages (indirect blocks, directories) which are
1194  * mapped via the block device.  Since these pages could have journal heads
1195  * which would prevent try_to_free_buffers() from freeing them, we must use
1196  * jbd2 layer's try_to_free_buffers() function to release them.
1197  */
1198 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1199                                  gfp_t wait)
1200 {
1201         journal_t *journal = EXT4_SB(sb)->s_journal;
1202
1203         WARN_ON(PageChecked(page));
1204         if (!page_has_buffers(page))
1205                 return 0;
1206         if (journal)
1207                 return jbd2_journal_try_to_free_buffers(journal, page,
1208                                                 wait & ~__GFP_DIRECT_RECLAIM);
1209         return try_to_free_buffers(page);
1210 }
1211
1212 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1213 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1214 {
1215         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1216                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1217 }
1218
1219 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1220                                                         void *fs_data)
1221 {
1222         handle_t *handle = fs_data;
1223         int res, res2, credits, retries = 0;
1224
1225         /*
1226          * Encrypting the root directory is not allowed because e2fsck expects
1227          * lost+found to exist and be unencrypted, and encrypting the root
1228          * directory would imply encrypting the lost+found directory as well as
1229          * the filename "lost+found" itself.
1230          */
1231         if (inode->i_ino == EXT4_ROOT_INO)
1232                 return -EPERM;
1233
1234         if (WARN_ON_ONCE(IS_DAX(inode) && i_size_read(inode)))
1235                 return -EINVAL;
1236
1237         res = ext4_convert_inline_data(inode);
1238         if (res)
1239                 return res;
1240
1241         /*
1242          * If a journal handle was specified, then the encryption context is
1243          * being set on a new inode via inheritance and is part of a larger
1244          * transaction to create the inode.  Otherwise the encryption context is
1245          * being set on an existing inode in its own transaction.  Only in the
1246          * latter case should the "retry on ENOSPC" logic be used.
1247          */
1248
1249         if (handle) {
1250                 res = ext4_xattr_set_handle(handle, inode,
1251                                             EXT4_XATTR_INDEX_ENCRYPTION,
1252                                             EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1253                                             ctx, len, 0);
1254                 if (!res) {
1255                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1256                         ext4_clear_inode_state(inode,
1257                                         EXT4_STATE_MAY_INLINE_DATA);
1258                         /*
1259                          * Update inode->i_flags - S_ENCRYPTED will be enabled,
1260                          * S_DAX may be disabled
1261                          */
1262                         ext4_set_inode_flags(inode);
1263                 }
1264                 return res;
1265         }
1266
1267         res = dquot_initialize(inode);
1268         if (res)
1269                 return res;
1270 retry:
1271         res = ext4_xattr_set_credits(inode, len, false /* is_create */,
1272                                      &credits);
1273         if (res)
1274                 return res;
1275
1276         handle = ext4_journal_start(inode, EXT4_HT_MISC, credits);
1277         if (IS_ERR(handle))
1278                 return PTR_ERR(handle);
1279
1280         res = ext4_xattr_set_handle(handle, inode, EXT4_XATTR_INDEX_ENCRYPTION,
1281                                     EXT4_XATTR_NAME_ENCRYPTION_CONTEXT,
1282                                     ctx, len, 0);
1283         if (!res) {
1284                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1285                 /*
1286                  * Update inode->i_flags - S_ENCRYPTED will be enabled,
1287                  * S_DAX may be disabled
1288                  */
1289                 ext4_set_inode_flags(inode);
1290                 res = ext4_mark_inode_dirty(handle, inode);
1291                 if (res)
1292                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1293         }
1294         res2 = ext4_journal_stop(handle);
1295
1296         if (res == -ENOSPC && ext4_should_retry_alloc(inode->i_sb, &retries))
1297                 goto retry;
1298         if (!res)
1299                 res = res2;
1300         return res;
1301 }
1302
1303 static bool ext4_dummy_context(struct inode *inode)
1304 {
1305         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1306 }
1307
1308 static const struct fscrypt_operations ext4_cryptops = {
1309         .key_prefix             = "ext4:",
1310         .get_context            = ext4_get_context,
1311         .set_context            = ext4_set_context,
1312         .dummy_context          = ext4_dummy_context,
1313         .empty_dir              = ext4_empty_dir,
1314         .max_namelen            = EXT4_NAME_LEN,
1315 };
1316 #endif
1317
1318 #ifdef CONFIG_QUOTA
1319 static const char * const quotatypes[] = INITQFNAMES;
1320 #define QTYPE2NAME(t) (quotatypes[t])
1321
1322 static int ext4_write_dquot(struct dquot *dquot);
1323 static int ext4_acquire_dquot(struct dquot *dquot);
1324 static int ext4_release_dquot(struct dquot *dquot);
1325 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1326 static int ext4_write_info(struct super_block *sb, int type);
1327 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1328                          const struct path *path);
1329 static int ext4_quota_on_mount(struct super_block *sb, int type);
1330 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1331                                size_t len, loff_t off);
1332 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1333                                 const char *data, size_t len, loff_t off);
1334 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1335                              unsigned int flags);
1336 static int ext4_enable_quotas(struct super_block *sb);
1337 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1338
1339 static struct dquot **ext4_get_dquots(struct inode *inode)
1340 {
1341         return EXT4_I(inode)->i_dquot;
1342 }
1343
1344 static const struct dquot_operations ext4_quota_operations = {
1345         .get_reserved_space     = ext4_get_reserved_space,
1346         .write_dquot            = ext4_write_dquot,
1347         .acquire_dquot          = ext4_acquire_dquot,
1348         .release_dquot          = ext4_release_dquot,
1349         .mark_dirty             = ext4_mark_dquot_dirty,
1350         .write_info             = ext4_write_info,
1351         .alloc_dquot            = dquot_alloc,
1352         .destroy_dquot          = dquot_destroy,
1353         .get_projid             = ext4_get_projid,
1354         .get_inode_usage        = ext4_get_inode_usage,
1355         .get_next_id            = ext4_get_next_id,
1356 };
1357
1358 static const struct quotactl_ops ext4_qctl_operations = {
1359         .quota_on       = ext4_quota_on,
1360         .quota_off      = ext4_quota_off,
1361         .quota_sync     = dquot_quota_sync,
1362         .get_state      = dquot_get_state,
1363         .set_info       = dquot_set_dqinfo,
1364         .get_dqblk      = dquot_get_dqblk,
1365         .set_dqblk      = dquot_set_dqblk,
1366         .get_nextdqblk  = dquot_get_next_dqblk,
1367 };
1368 #endif
1369
1370 static const struct super_operations ext4_sops = {
1371         .alloc_inode    = ext4_alloc_inode,
1372         .destroy_inode  = ext4_destroy_inode,
1373         .write_inode    = ext4_write_inode,
1374         .dirty_inode    = ext4_dirty_inode,
1375         .drop_inode     = ext4_drop_inode,
1376         .evict_inode    = ext4_evict_inode,
1377         .put_super      = ext4_put_super,
1378         .sync_fs        = ext4_sync_fs,
1379         .freeze_fs      = ext4_freeze,
1380         .unfreeze_fs    = ext4_unfreeze,
1381         .statfs         = ext4_statfs,
1382         .remount_fs     = ext4_remount,
1383         .show_options   = ext4_show_options,
1384 #ifdef CONFIG_QUOTA
1385         .quota_read     = ext4_quota_read,
1386         .quota_write    = ext4_quota_write,
1387         .get_dquots     = ext4_get_dquots,
1388 #endif
1389         .bdev_try_to_free_page = bdev_try_to_free_page,
1390 };
1391
1392 static const struct export_operations ext4_export_ops = {
1393         .fh_to_dentry = ext4_fh_to_dentry,
1394         .fh_to_parent = ext4_fh_to_parent,
1395         .get_parent = ext4_get_parent,
1396 };
1397
1398 enum {
1399         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1400         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1401         Opt_nouid32, Opt_debug, Opt_removed,
1402         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1403         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1404         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1405         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1406         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1407         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1408         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1409         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1410         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1411         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1412         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_warn_on_error,
1413         Opt_nowarn_on_error, Opt_mblk_io_submit,
1414         Opt_lazytime, Opt_nolazytime, Opt_debug_want_extra_isize,
1415         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1416         Opt_inode_readahead_blks, Opt_journal_ioprio,
1417         Opt_dioread_nolock, Opt_dioread_lock,
1418         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1419         Opt_max_dir_size_kb, Opt_nojournal_checksum, Opt_nombcache,
1420 };
1421
1422 static const match_table_t tokens = {
1423         {Opt_bsd_df, "bsddf"},
1424         {Opt_minix_df, "minixdf"},
1425         {Opt_grpid, "grpid"},
1426         {Opt_grpid, "bsdgroups"},
1427         {Opt_nogrpid, "nogrpid"},
1428         {Opt_nogrpid, "sysvgroups"},
1429         {Opt_resgid, "resgid=%u"},
1430         {Opt_resuid, "resuid=%u"},
1431         {Opt_sb, "sb=%u"},
1432         {Opt_err_cont, "errors=continue"},
1433         {Opt_err_panic, "errors=panic"},
1434         {Opt_err_ro, "errors=remount-ro"},
1435         {Opt_nouid32, "nouid32"},
1436         {Opt_debug, "debug"},
1437         {Opt_removed, "oldalloc"},
1438         {Opt_removed, "orlov"},
1439         {Opt_user_xattr, "user_xattr"},
1440         {Opt_nouser_xattr, "nouser_xattr"},
1441         {Opt_acl, "acl"},
1442         {Opt_noacl, "noacl"},
1443         {Opt_noload, "norecovery"},
1444         {Opt_noload, "noload"},
1445         {Opt_removed, "nobh"},
1446         {Opt_removed, "bh"},
1447         {Opt_commit, "commit=%u"},
1448         {Opt_min_batch_time, "min_batch_time=%u"},
1449         {Opt_max_batch_time, "max_batch_time=%u"},
1450         {Opt_journal_dev, "journal_dev=%u"},
1451         {Opt_journal_path, "journal_path=%s"},
1452         {Opt_journal_checksum, "journal_checksum"},
1453         {Opt_nojournal_checksum, "nojournal_checksum"},
1454         {Opt_journal_async_commit, "journal_async_commit"},
1455         {Opt_abort, "abort"},
1456         {Opt_data_journal, "data=journal"},
1457         {Opt_data_ordered, "data=ordered"},
1458         {Opt_data_writeback, "data=writeback"},
1459         {Opt_data_err_abort, "data_err=abort"},
1460         {Opt_data_err_ignore, "data_err=ignore"},
1461         {Opt_offusrjquota, "usrjquota="},
1462         {Opt_usrjquota, "usrjquota=%s"},
1463         {Opt_offgrpjquota, "grpjquota="},
1464         {Opt_grpjquota, "grpjquota=%s"},
1465         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1466         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1467         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1468         {Opt_grpquota, "grpquota"},
1469         {Opt_noquota, "noquota"},
1470         {Opt_quota, "quota"},
1471         {Opt_usrquota, "usrquota"},
1472         {Opt_prjquota, "prjquota"},
1473         {Opt_barrier, "barrier=%u"},
1474         {Opt_barrier, "barrier"},
1475         {Opt_nobarrier, "nobarrier"},
1476         {Opt_i_version, "i_version"},
1477         {Opt_dax, "dax"},
1478         {Opt_stripe, "stripe=%u"},
1479         {Opt_delalloc, "delalloc"},
1480         {Opt_warn_on_error, "warn_on_error"},
1481         {Opt_nowarn_on_error, "nowarn_on_error"},
1482         {Opt_lazytime, "lazytime"},
1483         {Opt_nolazytime, "nolazytime"},
1484         {Opt_debug_want_extra_isize, "debug_want_extra_isize=%u"},
1485         {Opt_nodelalloc, "nodelalloc"},
1486         {Opt_removed, "mblk_io_submit"},
1487         {Opt_removed, "nomblk_io_submit"},
1488         {Opt_block_validity, "block_validity"},
1489         {Opt_noblock_validity, "noblock_validity"},
1490         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1491         {Opt_journal_ioprio, "journal_ioprio=%u"},
1492         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1493         {Opt_auto_da_alloc, "auto_da_alloc"},
1494         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1495         {Opt_dioread_nolock, "dioread_nolock"},
1496         {Opt_dioread_lock, "dioread_lock"},
1497         {Opt_discard, "discard"},
1498         {Opt_nodiscard, "nodiscard"},
1499         {Opt_init_itable, "init_itable=%u"},
1500         {Opt_init_itable, "init_itable"},
1501         {Opt_noinit_itable, "noinit_itable"},
1502         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1503         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1504         {Opt_nombcache, "nombcache"},
1505         {Opt_nombcache, "no_mbcache"},  /* for backward compatibility */
1506         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1507         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1508         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1509         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1510         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1511         {Opt_err, NULL},
1512 };
1513
1514 static ext4_fsblk_t get_sb_block(void **data)
1515 {
1516         ext4_fsblk_t    sb_block;
1517         char            *options = (char *) *data;
1518
1519         if (!options || strncmp(options, "sb=", 3) != 0)
1520                 return 1;       /* Default location */
1521
1522         options += 3;
1523         /* TODO: use simple_strtoll with >32bit ext4 */
1524         sb_block = simple_strtoul(options, &options, 0);
1525         if (*options && *options != ',') {
1526                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1527                        (char *) *data);
1528                 return 1;
1529         }
1530         if (*options == ',')
1531                 options++;
1532         *data = (void *) options;
1533
1534         return sb_block;
1535 }
1536
1537 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1538 static const char deprecated_msg[] =
1539         "Mount option \"%s\" will be removed by %s\n"
1540         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1541
1542 #ifdef CONFIG_QUOTA
1543 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1544 {
1545         struct ext4_sb_info *sbi = EXT4_SB(sb);
1546         char *qname, *old_qname = get_qf_name(sb, sbi, qtype);
1547         int ret = -1;
1548
1549         if (sb_any_quota_loaded(sb) && !old_qname) {
1550                 ext4_msg(sb, KERN_ERR,
1551                         "Cannot change journaled "
1552                         "quota options when quota turned on");
1553                 return -1;
1554         }
1555         if (ext4_has_feature_quota(sb)) {
1556                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1557                          "ignored when QUOTA feature is enabled");
1558                 return 1;
1559         }
1560         qname = match_strdup(args);
1561         if (!qname) {
1562                 ext4_msg(sb, KERN_ERR,
1563                         "Not enough memory for storing quotafile name");
1564                 return -1;
1565         }
1566         if (old_qname) {
1567                 if (strcmp(old_qname, qname) == 0)
1568                         ret = 1;
1569                 else
1570                         ext4_msg(sb, KERN_ERR,
1571                                  "%s quota file already specified",
1572                                  QTYPE2NAME(qtype));
1573                 goto errout;
1574         }
1575         if (strchr(qname, '/')) {
1576                 ext4_msg(sb, KERN_ERR,
1577                         "quotafile must be on filesystem root");
1578                 goto errout;
1579         }
1580         rcu_assign_pointer(sbi->s_qf_names[qtype], qname);
1581         set_opt(sb, QUOTA);
1582         return 1;
1583 errout:
1584         kfree(qname);
1585         return ret;
1586 }
1587
1588 static int clear_qf_name(struct super_block *sb, int qtype)
1589 {
1590
1591         struct ext4_sb_info *sbi = EXT4_SB(sb);
1592         char *old_qname = get_qf_name(sb, sbi, qtype);
1593
1594         if (sb_any_quota_loaded(sb) && old_qname) {
1595                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1596                         " when quota turned on");
1597                 return -1;
1598         }
1599         rcu_assign_pointer(sbi->s_qf_names[qtype], NULL);
1600         synchronize_rcu();
1601         kfree(old_qname);
1602         return 1;
1603 }
1604 #endif
1605
1606 #define MOPT_SET        0x0001
1607 #define MOPT_CLEAR      0x0002
1608 #define MOPT_NOSUPPORT  0x0004
1609 #define MOPT_EXPLICIT   0x0008
1610 #define MOPT_CLEAR_ERR  0x0010
1611 #define MOPT_GTE0       0x0020
1612 #ifdef CONFIG_QUOTA
1613 #define MOPT_Q          0
1614 #define MOPT_QFMT       0x0040
1615 #else
1616 #define MOPT_Q          MOPT_NOSUPPORT
1617 #define MOPT_QFMT       MOPT_NOSUPPORT
1618 #endif
1619 #define MOPT_DATAJ      0x0080
1620 #define MOPT_NO_EXT2    0x0100
1621 #define MOPT_NO_EXT3    0x0200
1622 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1623 #define MOPT_STRING     0x0400
1624
1625 static const struct mount_opts {
1626         int     token;
1627         int     mount_opt;
1628         int     flags;
1629 } ext4_mount_opts[] = {
1630         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1631         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1632         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1633         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1634         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1635         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1636         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1637          MOPT_EXT4_ONLY | MOPT_SET},
1638         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1639          MOPT_EXT4_ONLY | MOPT_CLEAR},
1640         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1641         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1642         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1643          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1644         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1645          MOPT_EXT4_ONLY | MOPT_CLEAR},
1646         {Opt_warn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_SET},
1647         {Opt_nowarn_on_error, EXT4_MOUNT_WARN_ON_ERROR, MOPT_CLEAR},
1648         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1649          MOPT_EXT4_ONLY | MOPT_CLEAR},
1650         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1651          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1652         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1653                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1654          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1655         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1656         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1657         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1658         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1659         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1660          MOPT_NO_EXT2},
1661         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1662          MOPT_NO_EXT2},
1663         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1664         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1665         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1666         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1667         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1668         {Opt_commit, 0, MOPT_GTE0},
1669         {Opt_max_batch_time, 0, MOPT_GTE0},
1670         {Opt_min_batch_time, 0, MOPT_GTE0},
1671         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1672         {Opt_init_itable, 0, MOPT_GTE0},
1673         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1674         {Opt_stripe, 0, MOPT_GTE0},
1675         {Opt_resuid, 0, MOPT_GTE0},
1676         {Opt_resgid, 0, MOPT_GTE0},
1677         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1678         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1679         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1680         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1681         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1682         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1683          MOPT_NO_EXT2 | MOPT_DATAJ},
1684         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1685         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1686 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1687         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1688         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1689 #else
1690         {Opt_acl, 0, MOPT_NOSUPPORT},
1691         {Opt_noacl, 0, MOPT_NOSUPPORT},
1692 #endif
1693         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1694         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1695         {Opt_debug_want_extra_isize, 0, MOPT_GTE0},
1696         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1697         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1698                                                         MOPT_SET | MOPT_Q},
1699         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1700                                                         MOPT_SET | MOPT_Q},
1701         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1702                                                         MOPT_SET | MOPT_Q},
1703         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1704                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1705                                                         MOPT_CLEAR | MOPT_Q},
1706         {Opt_usrjquota, 0, MOPT_Q},
1707         {Opt_grpjquota, 0, MOPT_Q},
1708         {Opt_offusrjquota, 0, MOPT_Q},
1709         {Opt_offgrpjquota, 0, MOPT_Q},
1710         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1711         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1712         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1713         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1714         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1715         {Opt_nombcache, EXT4_MOUNT_NO_MBCACHE, MOPT_SET},
1716         {Opt_err, 0, 0}
1717 };
1718
1719 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1720                             substring_t *args, unsigned long *journal_devnum,
1721                             unsigned int *journal_ioprio, int is_remount)
1722 {
1723         struct ext4_sb_info *sbi = EXT4_SB(sb);
1724         const struct mount_opts *m;
1725         kuid_t uid;
1726         kgid_t gid;
1727         int arg = 0;
1728
1729 #ifdef CONFIG_QUOTA
1730         if (token == Opt_usrjquota)
1731                 return set_qf_name(sb, USRQUOTA, &args[0]);
1732         else if (token == Opt_grpjquota)
1733                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1734         else if (token == Opt_offusrjquota)
1735                 return clear_qf_name(sb, USRQUOTA);
1736         else if (token == Opt_offgrpjquota)
1737                 return clear_qf_name(sb, GRPQUOTA);
1738 #endif
1739         switch (token) {
1740         case Opt_noacl:
1741         case Opt_nouser_xattr:
1742                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1743                 break;
1744         case Opt_sb:
1745                 return 1;       /* handled by get_sb_block() */
1746         case Opt_removed:
1747                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1748                 return 1;
1749         case Opt_abort:
1750                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1751                 return 1;
1752         case Opt_i_version:
1753                 sb->s_flags |= SB_I_VERSION;
1754                 return 1;
1755         case Opt_lazytime:
1756                 sb->s_flags |= SB_LAZYTIME;
1757                 return 1;
1758         case Opt_nolazytime:
1759                 sb->s_flags &= ~SB_LAZYTIME;
1760                 return 1;
1761         }
1762
1763         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1764                 if (token == m->token)
1765                         break;
1766
1767         if (m->token == Opt_err) {
1768                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1769                          "or missing value", opt);
1770                 return -1;
1771         }
1772
1773         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1774                 ext4_msg(sb, KERN_ERR,
1775                          "Mount option \"%s\" incompatible with ext2", opt);
1776                 return -1;
1777         }
1778         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1779                 ext4_msg(sb, KERN_ERR,
1780                          "Mount option \"%s\" incompatible with ext3", opt);
1781                 return -1;
1782         }
1783
1784         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1785                 return -1;
1786         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1787                 return -1;
1788         if (m->flags & MOPT_EXPLICIT) {
1789                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1790                         set_opt2(sb, EXPLICIT_DELALLOC);
1791                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1792                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1793                 } else
1794                         return -1;
1795         }
1796         if (m->flags & MOPT_CLEAR_ERR)
1797                 clear_opt(sb, ERRORS_MASK);
1798         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1799                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1800                          "options when quota turned on");
1801                 return -1;
1802         }
1803
1804         if (m->flags & MOPT_NOSUPPORT) {
1805                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1806         } else if (token == Opt_commit) {
1807                 if (arg == 0)
1808                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1809                 sbi->s_commit_interval = HZ * arg;
1810         } else if (token == Opt_debug_want_extra_isize) {
1811                 sbi->s_want_extra_isize = arg;
1812         } else if (token == Opt_max_batch_time) {
1813                 sbi->s_max_batch_time = arg;
1814         } else if (token == Opt_min_batch_time) {
1815                 sbi->s_min_batch_time = arg;
1816         } else if (token == Opt_inode_readahead_blks) {
1817                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1818                         ext4_msg(sb, KERN_ERR,
1819                                  "EXT4-fs: inode_readahead_blks must be "
1820                                  "0 or a power of 2 smaller than 2^31");
1821                         return -1;
1822                 }
1823                 sbi->s_inode_readahead_blks = arg;
1824         } else if (token == Opt_init_itable) {
1825                 set_opt(sb, INIT_INODE_TABLE);
1826                 if (!args->from)
1827                         arg = EXT4_DEF_LI_WAIT_MULT;
1828                 sbi->s_li_wait_mult = arg;
1829         } else if (token == Opt_max_dir_size_kb) {
1830                 sbi->s_max_dir_size_kb = arg;
1831         } else if (token == Opt_stripe) {
1832                 sbi->s_stripe = arg;
1833         } else if (token == Opt_resuid) {
1834                 uid = make_kuid(current_user_ns(), arg);
1835                 if (!uid_valid(uid)) {
1836                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1837                         return -1;
1838                 }
1839                 sbi->s_resuid = uid;
1840         } else if (token == Opt_resgid) {
1841                 gid = make_kgid(current_user_ns(), arg);
1842                 if (!gid_valid(gid)) {
1843                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1844                         return -1;
1845                 }
1846                 sbi->s_resgid = gid;
1847         } else if (token == Opt_journal_dev) {
1848                 if (is_remount) {
1849                         ext4_msg(sb, KERN_ERR,
1850                                  "Cannot specify journal on remount");
1851                         return -1;
1852                 }
1853                 *journal_devnum = arg;
1854         } else if (token == Opt_journal_path) {
1855                 char *journal_path;
1856                 struct inode *journal_inode;
1857                 struct path path;
1858                 int error;
1859
1860                 if (is_remount) {
1861                         ext4_msg(sb, KERN_ERR,
1862                                  "Cannot specify journal on remount");
1863                         return -1;
1864                 }
1865                 journal_path = match_strdup(&args[0]);
1866                 if (!journal_path) {
1867                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1868                                 "journal device string");
1869                         return -1;
1870                 }
1871
1872                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1873                 if (error) {
1874                         ext4_msg(sb, KERN_ERR, "error: could not find "
1875                                 "journal device path: error %d", error);
1876                         kfree(journal_path);
1877                         return -1;
1878                 }
1879
1880                 journal_inode = d_inode(path.dentry);
1881                 if (!S_ISBLK(journal_inode->i_mode)) {
1882                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1883                                 "is not a block device", journal_path);
1884                         path_put(&path);
1885                         kfree(journal_path);
1886                         return -1;
1887                 }
1888
1889                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1890                 path_put(&path);
1891                 kfree(journal_path);
1892         } else if (token == Opt_journal_ioprio) {
1893                 if (arg > 7) {
1894                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1895                                  " (must be 0-7)");
1896                         return -1;
1897                 }
1898                 *journal_ioprio =
1899                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1900         } else if (token == Opt_test_dummy_encryption) {
1901 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1902                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1903                 ext4_msg(sb, KERN_WARNING,
1904                          "Test dummy encryption mode enabled");
1905 #else
1906                 ext4_msg(sb, KERN_WARNING,
1907                          "Test dummy encryption mount option ignored");
1908 #endif
1909         } else if (m->flags & MOPT_DATAJ) {
1910                 if (is_remount) {
1911                         if (!sbi->s_journal)
1912                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1913                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1914                                 ext4_msg(sb, KERN_ERR,
1915                                          "Cannot change data mode on remount");
1916                                 return -1;
1917                         }
1918                 } else {
1919                         clear_opt(sb, DATA_FLAGS);
1920                         sbi->s_mount_opt |= m->mount_opt;
1921                 }
1922 #ifdef CONFIG_QUOTA
1923         } else if (m->flags & MOPT_QFMT) {
1924                 if (sb_any_quota_loaded(sb) &&
1925                     sbi->s_jquota_fmt != m->mount_opt) {
1926                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1927                                  "quota options when quota turned on");
1928                         return -1;
1929                 }
1930                 if (ext4_has_feature_quota(sb)) {
1931                         ext4_msg(sb, KERN_INFO,
1932                                  "Quota format mount options ignored "
1933                                  "when QUOTA feature is enabled");
1934                         return 1;
1935                 }
1936                 sbi->s_jquota_fmt = m->mount_opt;
1937 #endif
1938         } else if (token == Opt_dax) {
1939 #ifdef CONFIG_FS_DAX
1940                 ext4_msg(sb, KERN_WARNING,
1941                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1942                         sbi->s_mount_opt |= m->mount_opt;
1943 #else
1944                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1945                 return -1;
1946 #endif
1947         } else if (token == Opt_data_err_abort) {
1948                 sbi->s_mount_opt |= m->mount_opt;
1949         } else if (token == Opt_data_err_ignore) {
1950                 sbi->s_mount_opt &= ~m->mount_opt;
1951         } else {
1952                 if (!args->from)
1953                         arg = 1;
1954                 if (m->flags & MOPT_CLEAR)
1955                         arg = !arg;
1956                 else if (unlikely(!(m->flags & MOPT_SET))) {
1957                         ext4_msg(sb, KERN_WARNING,
1958                                  "buggy handling of option %s", opt);
1959                         WARN_ON(1);
1960                         return -1;
1961                 }
1962                 if (arg != 0)
1963                         sbi->s_mount_opt |= m->mount_opt;
1964                 else
1965                         sbi->s_mount_opt &= ~m->mount_opt;
1966         }
1967         return 1;
1968 }
1969
1970 static int parse_options(char *options, struct super_block *sb,
1971                          unsigned long *journal_devnum,
1972                          unsigned int *journal_ioprio,
1973                          int is_remount)
1974 {
1975         struct ext4_sb_info *sbi = EXT4_SB(sb);
1976         char *p, __maybe_unused *usr_qf_name, __maybe_unused *grp_qf_name;
1977         substring_t args[MAX_OPT_ARGS];
1978         int token;
1979
1980         if (!options)
1981                 return 1;
1982
1983         while ((p = strsep(&options, ",")) != NULL) {
1984                 if (!*p)
1985                         continue;
1986                 /*
1987                  * Initialize args struct so we know whether arg was
1988                  * found; some options take optional arguments.
1989                  */
1990                 args[0].to = args[0].from = NULL;
1991                 token = match_token(p, tokens, args);
1992                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1993                                      journal_ioprio, is_remount) < 0)
1994                         return 0;
1995         }
1996 #ifdef CONFIG_QUOTA
1997         /*
1998          * We do the test below only for project quotas. 'usrquota' and
1999          * 'grpquota' mount options are allowed even without quota feature
2000          * to support legacy quotas in quota files.
2001          */
2002         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
2003                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
2004                          "Cannot enable project quota enforcement.");
2005                 return 0;
2006         }
2007         usr_qf_name = get_qf_name(sb, sbi, USRQUOTA);
2008         grp_qf_name = get_qf_name(sb, sbi, GRPQUOTA);
2009         if (usr_qf_name || grp_qf_name) {
2010                 if (test_opt(sb, USRQUOTA) && usr_qf_name)
2011                         clear_opt(sb, USRQUOTA);
2012
2013                 if (test_opt(sb, GRPQUOTA) && grp_qf_name)
2014                         clear_opt(sb, GRPQUOTA);
2015
2016                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
2017                         ext4_msg(sb, KERN_ERR, "old and new quota "
2018                                         "format mixing");
2019                         return 0;
2020                 }
2021
2022                 if (!sbi->s_jquota_fmt) {
2023                         ext4_msg(sb, KERN_ERR, "journaled quota format "
2024                                         "not specified");
2025                         return 0;
2026                 }
2027         }
2028 #endif
2029         if (test_opt(sb, DIOREAD_NOLOCK)) {
2030                 int blocksize =
2031                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
2032
2033                 if (blocksize < PAGE_SIZE) {
2034                         ext4_msg(sb, KERN_ERR, "can't mount with "
2035                                  "dioread_nolock if block size != PAGE_SIZE");
2036                         return 0;
2037                 }
2038         }
2039         return 1;
2040 }
2041
2042 static inline void ext4_show_quota_options(struct seq_file *seq,
2043                                            struct super_block *sb)
2044 {
2045 #if defined(CONFIG_QUOTA)
2046         struct ext4_sb_info *sbi = EXT4_SB(sb);
2047         char *usr_qf_name, *grp_qf_name;
2048
2049         if (sbi->s_jquota_fmt) {
2050                 char *fmtname = "";
2051
2052                 switch (sbi->s_jquota_fmt) {
2053                 case QFMT_VFS_OLD:
2054                         fmtname = "vfsold";
2055                         break;
2056                 case QFMT_VFS_V0:
2057                         fmtname = "vfsv0";
2058                         break;
2059                 case QFMT_VFS_V1:
2060                         fmtname = "vfsv1";
2061                         break;
2062                 }
2063                 seq_printf(seq, ",jqfmt=%s", fmtname);
2064         }
2065
2066         rcu_read_lock();
2067         usr_qf_name = rcu_dereference(sbi->s_qf_names[USRQUOTA]);
2068         grp_qf_name = rcu_dereference(sbi->s_qf_names[GRPQUOTA]);
2069         if (usr_qf_name)
2070                 seq_show_option(seq, "usrjquota", usr_qf_name);
2071         if (grp_qf_name)
2072                 seq_show_option(seq, "grpjquota", grp_qf_name);
2073         rcu_read_unlock();
2074 #endif
2075 }
2076
2077 static const char *token2str(int token)
2078 {
2079         const struct match_token *t;
2080
2081         for (t = tokens; t->token != Opt_err; t++)
2082                 if (t->token == token && !strchr(t->pattern, '='))
2083                         break;
2084         return t->pattern;
2085 }
2086
2087 /*
2088  * Show an option if
2089  *  - it's set to a non-default value OR
2090  *  - if the per-sb default is different from the global default
2091  */
2092 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
2093                               int nodefs)
2094 {
2095         struct ext4_sb_info *sbi = EXT4_SB(sb);
2096         struct ext4_super_block *es = sbi->s_es;
2097         int def_errors, def_mount_opt = sbi->s_def_mount_opt;
2098         const struct mount_opts *m;
2099         char sep = nodefs ? '\n' : ',';
2100
2101 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
2102 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
2103
2104         if (sbi->s_sb_block != 1)
2105                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
2106
2107         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
2108                 int want_set = m->flags & MOPT_SET;
2109                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
2110                     (m->flags & MOPT_CLEAR_ERR))
2111                         continue;
2112                 if (!nodefs && !(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
2113                         continue; /* skip if same as the default */
2114                 if ((want_set &&
2115                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
2116                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
2117                         continue; /* select Opt_noFoo vs Opt_Foo */
2118                 SEQ_OPTS_PRINT("%s", token2str(m->token));
2119         }
2120
2121         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
2122             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
2123                 SEQ_OPTS_PRINT("resuid=%u",
2124                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
2125         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
2126             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
2127                 SEQ_OPTS_PRINT("resgid=%u",
2128                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
2129         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
2130         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
2131                 SEQ_OPTS_PUTS("errors=remount-ro");
2132         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
2133                 SEQ_OPTS_PUTS("errors=continue");
2134         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2135                 SEQ_OPTS_PUTS("errors=panic");
2136         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2137                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2138         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2139                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2140         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2141                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2142         if (sb->s_flags & SB_I_VERSION)
2143                 SEQ_OPTS_PUTS("i_version");
2144         if (nodefs || sbi->s_stripe)
2145                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2146         if (nodefs || EXT4_MOUNT_DATA_FLAGS &
2147                         (sbi->s_mount_opt ^ def_mount_opt)) {
2148                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2149                         SEQ_OPTS_PUTS("data=journal");
2150                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2151                         SEQ_OPTS_PUTS("data=ordered");
2152                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2153                         SEQ_OPTS_PUTS("data=writeback");
2154         }
2155         if (nodefs ||
2156             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2157                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2158                                sbi->s_inode_readahead_blks);
2159
2160         if (test_opt(sb, INIT_INODE_TABLE) && (nodefs ||
2161                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2162                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2163         if (nodefs || sbi->s_max_dir_size_kb)
2164                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2165         if (test_opt(sb, DATA_ERR_ABORT))
2166                 SEQ_OPTS_PUTS("data_err=abort");
2167         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2168                 SEQ_OPTS_PUTS("test_dummy_encryption");
2169
2170         ext4_show_quota_options(seq, sb);
2171         return 0;
2172 }
2173
2174 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2175 {
2176         return _ext4_show_options(seq, root->d_sb, 0);
2177 }
2178
2179 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2180 {
2181         struct super_block *sb = seq->private;
2182         int rc;
2183
2184         seq_puts(seq, sb_rdonly(sb) ? "ro" : "rw");
2185         rc = _ext4_show_options(seq, sb, 1);
2186         seq_puts(seq, "\n");
2187         return rc;
2188 }
2189
2190 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2191                             int read_only)
2192 {
2193         struct ext4_sb_info *sbi = EXT4_SB(sb);
2194         int err = 0;
2195
2196         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2197                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2198                          "forcing read-only mode");
2199                 err = -EROFS;
2200         }
2201         if (read_only)
2202                 goto done;
2203         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2204                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2205                          "running e2fsck is recommended");
2206         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2207                 ext4_msg(sb, KERN_WARNING,
2208                          "warning: mounting fs with errors, "
2209                          "running e2fsck is recommended");
2210         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2211                  le16_to_cpu(es->s_mnt_count) >=
2212                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2213                 ext4_msg(sb, KERN_WARNING,
2214                          "warning: maximal mount count reached, "
2215                          "running e2fsck is recommended");
2216         else if (le32_to_cpu(es->s_checkinterval) &&
2217                  (ext4_get_tstamp(es, s_lastcheck) +
2218                   le32_to_cpu(es->s_checkinterval) <= ktime_get_real_seconds()))
2219                 ext4_msg(sb, KERN_WARNING,
2220                          "warning: checktime reached, "
2221                          "running e2fsck is recommended");
2222         if (!sbi->s_journal)
2223                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2224         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2225                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2226         le16_add_cpu(&es->s_mnt_count, 1);
2227         ext4_update_tstamp(es, s_mtime);
2228         ext4_update_dynamic_rev(sb);
2229         if (sbi->s_journal)
2230                 ext4_set_feature_journal_needs_recovery(sb);
2231
2232         err = ext4_commit_super(sb, 1);
2233 done:
2234         if (test_opt(sb, DEBUG))
2235                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2236                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2237                         sb->s_blocksize,
2238                         sbi->s_groups_count,
2239                         EXT4_BLOCKS_PER_GROUP(sb),
2240                         EXT4_INODES_PER_GROUP(sb),
2241                         sbi->s_mount_opt, sbi->s_mount_opt2);
2242
2243         cleancache_init_fs(sb);
2244         return err;
2245 }
2246
2247 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2248 {
2249         struct ext4_sb_info *sbi = EXT4_SB(sb);
2250         struct flex_groups *new_groups;
2251         int size;
2252
2253         if (!sbi->s_log_groups_per_flex)
2254                 return 0;
2255
2256         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2257         if (size <= sbi->s_flex_groups_allocated)
2258                 return 0;
2259
2260         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
2261         new_groups = kvzalloc(size, GFP_KERNEL);
2262         if (!new_groups) {
2263                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
2264                          size / (int) sizeof(struct flex_groups));
2265                 return -ENOMEM;
2266         }
2267
2268         if (sbi->s_flex_groups) {
2269                 memcpy(new_groups, sbi->s_flex_groups,
2270                        (sbi->s_flex_groups_allocated *
2271                         sizeof(struct flex_groups)));
2272                 kvfree(sbi->s_flex_groups);
2273         }
2274         sbi->s_flex_groups = new_groups;
2275         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
2276         return 0;
2277 }
2278
2279 static int ext4_fill_flex_info(struct super_block *sb)
2280 {
2281         struct ext4_sb_info *sbi = EXT4_SB(sb);
2282         struct ext4_group_desc *gdp = NULL;
2283         ext4_group_t flex_group;
2284         int i, err;
2285
2286         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2287         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2288                 sbi->s_log_groups_per_flex = 0;
2289                 return 1;
2290         }
2291
2292         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2293         if (err)
2294                 goto failed;
2295
2296         for (i = 0; i < sbi->s_groups_count; i++) {
2297                 gdp = ext4_get_group_desc(sb, i, NULL);
2298
2299                 flex_group = ext4_flex_group(sbi, i);
2300                 atomic_add(ext4_free_inodes_count(sb, gdp),
2301                            &sbi->s_flex_groups[flex_group].free_inodes);
2302                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2303                              &sbi->s_flex_groups[flex_group].free_clusters);
2304                 atomic_add(ext4_used_dirs_count(sb, gdp),
2305                            &sbi->s_flex_groups[flex_group].used_dirs);
2306         }
2307
2308         return 1;
2309 failed:
2310         return 0;
2311 }
2312
2313 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2314                                    struct ext4_group_desc *gdp)
2315 {
2316         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2317         __u16 crc = 0;
2318         __le32 le_group = cpu_to_le32(block_group);
2319         struct ext4_sb_info *sbi = EXT4_SB(sb);
2320
2321         if (ext4_has_metadata_csum(sbi->s_sb)) {
2322                 /* Use new metadata_csum algorithm */
2323                 __u32 csum32;
2324                 __u16 dummy_csum = 0;
2325
2326                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2327                                      sizeof(le_group));
2328                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2329                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2330                                      sizeof(dummy_csum));
2331                 offset += sizeof(dummy_csum);
2332                 if (offset < sbi->s_desc_size)
2333                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2334                                              sbi->s_desc_size - offset);
2335
2336                 crc = csum32 & 0xFFFF;
2337                 goto out;
2338         }
2339
2340         /* old crc16 code */
2341         if (!ext4_has_feature_gdt_csum(sb))
2342                 return 0;
2343
2344         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2345         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2346         crc = crc16(crc, (__u8 *)gdp, offset);
2347         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2348         /* for checksum of struct ext4_group_desc do the rest...*/
2349         if (ext4_has_feature_64bit(sb) &&
2350             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2351                 crc = crc16(crc, (__u8 *)gdp + offset,
2352                             le16_to_cpu(sbi->s_es->s_desc_size) -
2353                                 offset);
2354
2355 out:
2356         return cpu_to_le16(crc);
2357 }
2358
2359 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2360                                 struct ext4_group_desc *gdp)
2361 {
2362         if (ext4_has_group_desc_csum(sb) &&
2363             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2364                 return 0;
2365
2366         return 1;
2367 }
2368
2369 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2370                               struct ext4_group_desc *gdp)
2371 {
2372         if (!ext4_has_group_desc_csum(sb))
2373                 return;
2374         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2375 }
2376
2377 /* Called at mount-time, super-block is locked */
2378 static int ext4_check_descriptors(struct super_block *sb,
2379                                   ext4_fsblk_t sb_block,
2380                                   ext4_group_t *first_not_zeroed)
2381 {
2382         struct ext4_sb_info *sbi = EXT4_SB(sb);
2383         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2384         ext4_fsblk_t last_block;
2385         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2386         ext4_fsblk_t block_bitmap;
2387         ext4_fsblk_t inode_bitmap;
2388         ext4_fsblk_t inode_table;
2389         int flexbg_flag = 0;
2390         ext4_group_t i, grp = sbi->s_groups_count;
2391
2392         if (ext4_has_feature_flex_bg(sb))
2393                 flexbg_flag = 1;
2394
2395         ext4_debug("Checking group descriptors");
2396
2397         for (i = 0; i < sbi->s_groups_count; i++) {
2398                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2399
2400                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2401                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2402                 else
2403                         last_block = first_block +
2404                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2405
2406                 if ((grp == sbi->s_groups_count) &&
2407                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2408                         grp = i;
2409
2410                 block_bitmap = ext4_block_bitmap(sb, gdp);
2411                 if (block_bitmap == sb_block) {
2412                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2413                                  "Block bitmap for group %u overlaps "
2414                                  "superblock", i);
2415                         if (!sb_rdonly(sb))
2416                                 return 0;
2417                 }
2418                 if (block_bitmap >= sb_block + 1 &&
2419                     block_bitmap <= last_bg_block) {
2420                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2421                                  "Block bitmap for group %u overlaps "
2422                                  "block group descriptors", i);
2423                         if (!sb_rdonly(sb))
2424                                 return 0;
2425                 }
2426                 if (block_bitmap < first_block || block_bitmap > last_block) {
2427                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2428                                "Block bitmap for group %u not in group "
2429                                "(block %llu)!", i, block_bitmap);
2430                         return 0;
2431                 }
2432                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2433                 if (inode_bitmap == sb_block) {
2434                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2435                                  "Inode bitmap for group %u overlaps "
2436                                  "superblock", i);
2437                         if (!sb_rdonly(sb))
2438                                 return 0;
2439                 }
2440                 if (inode_bitmap >= sb_block + 1 &&
2441                     inode_bitmap <= last_bg_block) {
2442                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2443                                  "Inode bitmap for group %u overlaps "
2444                                  "block group descriptors", i);
2445                         if (!sb_rdonly(sb))
2446                                 return 0;
2447                 }
2448                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2449                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2450                                "Inode bitmap for group %u not in group "
2451                                "(block %llu)!", i, inode_bitmap);
2452                         return 0;
2453                 }
2454                 inode_table = ext4_inode_table(sb, gdp);
2455                 if (inode_table == sb_block) {
2456                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2457                                  "Inode table for group %u overlaps "
2458                                  "superblock", i);
2459                         if (!sb_rdonly(sb))
2460                                 return 0;
2461                 }
2462                 if (inode_table >= sb_block + 1 &&
2463                     inode_table <= last_bg_block) {
2464                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2465                                  "Inode table for group %u overlaps "
2466                                  "block group descriptors", i);
2467                         if (!sb_rdonly(sb))
2468                                 return 0;
2469                 }
2470                 if (inode_table < first_block ||
2471                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2472                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2473                                "Inode table for group %u not in group "
2474                                "(block %llu)!", i, inode_table);
2475                         return 0;
2476                 }
2477                 ext4_lock_group(sb, i);
2478                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2479                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2480                                  "Checksum for group %u failed (%u!=%u)",
2481                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2482                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2483                         if (!sb_rdonly(sb)) {
2484                                 ext4_unlock_group(sb, i);
2485                                 return 0;
2486                         }
2487                 }
2488                 ext4_unlock_group(sb, i);
2489                 if (!flexbg_flag)
2490                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2491         }
2492         if (NULL != first_not_zeroed)
2493                 *first_not_zeroed = grp;
2494         return 1;
2495 }
2496
2497 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2498  * the superblock) which were deleted from all directories, but held open by
2499  * a process at the time of a crash.  We walk the list and try to delete these
2500  * inodes at recovery time (only with a read-write filesystem).
2501  *
2502  * In order to keep the orphan inode chain consistent during traversal (in
2503  * case of crash during recovery), we link each inode into the superblock
2504  * orphan list_head and handle it the same way as an inode deletion during
2505  * normal operation (which journals the operations for us).
2506  *
2507  * We only do an iget() and an iput() on each inode, which is very safe if we
2508  * accidentally point at an in-use or already deleted inode.  The worst that
2509  * can happen in this case is that we get a "bit already cleared" message from
2510  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2511  * e2fsck was run on this filesystem, and it must have already done the orphan
2512  * inode cleanup for us, so we can safely abort without any further action.
2513  */
2514 static void ext4_orphan_cleanup(struct super_block *sb,
2515                                 struct ext4_super_block *es)
2516 {
2517         unsigned int s_flags = sb->s_flags;
2518         int ret, nr_orphans = 0, nr_truncates = 0;
2519 #ifdef CONFIG_QUOTA
2520         int quota_update = 0;
2521         int i;
2522 #endif
2523         if (!es->s_last_orphan) {
2524                 jbd_debug(4, "no orphan inodes to clean up\n");
2525                 return;
2526         }
2527
2528         if (bdev_read_only(sb->s_bdev)) {
2529                 ext4_msg(sb, KERN_ERR, "write access "
2530                         "unavailable, skipping orphan cleanup");
2531                 return;
2532         }
2533
2534         /* Check if feature set would not allow a r/w mount */
2535         if (!ext4_feature_set_ok(sb, 0)) {
2536                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2537                          "unknown ROCOMPAT features");
2538                 return;
2539         }
2540
2541         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2542                 /* don't clear list on RO mount w/ errors */
2543                 if (es->s_last_orphan && !(s_flags & SB_RDONLY)) {
2544                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2545                                   "clearing orphan list.\n");
2546                         es->s_last_orphan = 0;
2547                 }
2548                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2549                 return;
2550         }
2551
2552         if (s_flags & SB_RDONLY) {
2553                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2554                 sb->s_flags &= ~SB_RDONLY;
2555         }
2556 #ifdef CONFIG_QUOTA
2557         /* Needed for iput() to work correctly and not trash data */
2558         sb->s_flags |= SB_ACTIVE;
2559
2560         /*
2561          * Turn on quotas which were not enabled for read-only mounts if
2562          * filesystem has quota feature, so that they are updated correctly.
2563          */
2564         if (ext4_has_feature_quota(sb) && (s_flags & SB_RDONLY)) {
2565                 int ret = ext4_enable_quotas(sb);
2566
2567                 if (!ret)
2568                         quota_update = 1;
2569                 else
2570                         ext4_msg(sb, KERN_ERR,
2571                                 "Cannot turn on quotas: error %d", ret);
2572         }
2573
2574         /* Turn on journaled quotas used for old sytle */
2575         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2576                 if (EXT4_SB(sb)->s_qf_names[i]) {
2577                         int ret = ext4_quota_on_mount(sb, i);
2578
2579                         if (!ret)
2580                                 quota_update = 1;
2581                         else
2582                                 ext4_msg(sb, KERN_ERR,
2583                                         "Cannot turn on journaled "
2584                                         "quota: type %d: error %d", i, ret);
2585                 }
2586         }
2587 #endif
2588
2589         while (es->s_last_orphan) {
2590                 struct inode *inode;
2591
2592                 /*
2593                  * We may have encountered an error during cleanup; if
2594                  * so, skip the rest.
2595                  */
2596                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2597                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2598                         es->s_last_orphan = 0;
2599                         break;
2600                 }
2601
2602                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2603                 if (IS_ERR(inode)) {
2604                         es->s_last_orphan = 0;
2605                         break;
2606                 }
2607
2608                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2609                 dquot_initialize(inode);
2610                 if (inode->i_nlink) {
2611                         if (test_opt(sb, DEBUG))
2612                                 ext4_msg(sb, KERN_DEBUG,
2613                                         "%s: truncating inode %lu to %lld bytes",
2614                                         __func__, inode->i_ino, inode->i_size);
2615                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2616                                   inode->i_ino, inode->i_size);
2617                         inode_lock(inode);
2618                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2619                         ret = ext4_truncate(inode);
2620                         if (ret)
2621                                 ext4_std_error(inode->i_sb, ret);
2622                         inode_unlock(inode);
2623                         nr_truncates++;
2624                 } else {
2625                         if (test_opt(sb, DEBUG))
2626                                 ext4_msg(sb, KERN_DEBUG,
2627                                         "%s: deleting unreferenced inode %lu",
2628                                         __func__, inode->i_ino);
2629                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2630                                   inode->i_ino);
2631                         nr_orphans++;
2632                 }
2633                 iput(inode);  /* The delete magic happens here! */
2634         }
2635
2636 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2637
2638         if (nr_orphans)
2639                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2640                        PLURAL(nr_orphans));
2641         if (nr_truncates)
2642                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2643                        PLURAL(nr_truncates));
2644 #ifdef CONFIG_QUOTA
2645         /* Turn off quotas if they were enabled for orphan cleanup */
2646         if (quota_update) {
2647                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2648                         if (sb_dqopt(sb)->files[i])
2649                                 dquot_quota_off(sb, i);
2650                 }
2651         }
2652 #endif
2653         sb->s_flags = s_flags; /* Restore SB_RDONLY status */
2654 }
2655
2656 /*
2657  * Maximal extent format file size.
2658  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2659  * extent format containers, within a sector_t, and within i_blocks
2660  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2661  * so that won't be a limiting factor.
2662  *
2663  * However there is other limiting factor. We do store extents in the form
2664  * of starting block and length, hence the resulting length of the extent
2665  * covering maximum file size must fit into on-disk format containers as
2666  * well. Given that length is always by 1 unit bigger than max unit (because
2667  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2668  *
2669  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2670  */
2671 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2672 {
2673         loff_t res;
2674         loff_t upper_limit = MAX_LFS_FILESIZE;
2675
2676         /* small i_blocks in vfs inode? */
2677         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2678                 /*
2679                  * CONFIG_LBDAF is not enabled implies the inode
2680                  * i_block represent total blocks in 512 bytes
2681                  * 32 == size of vfs inode i_blocks * 8
2682                  */
2683                 upper_limit = (1LL << 32) - 1;
2684
2685                 /* total blocks in file system block size */
2686                 upper_limit >>= (blkbits - 9);
2687                 upper_limit <<= blkbits;
2688         }
2689
2690         /*
2691          * 32-bit extent-start container, ee_block. We lower the maxbytes
2692          * by one fs block, so ee_len can cover the extent of maximum file
2693          * size
2694          */
2695         res = (1LL << 32) - 1;
2696         res <<= blkbits;
2697
2698         /* Sanity check against vm- & vfs- imposed limits */
2699         if (res > upper_limit)
2700                 res = upper_limit;
2701
2702         return res;
2703 }
2704
2705 /*
2706  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2707  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2708  * We need to be 1 filesystem block less than the 2^48 sector limit.
2709  */
2710 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2711 {
2712         loff_t res = EXT4_NDIR_BLOCKS;
2713         int meta_blocks;
2714         loff_t upper_limit;
2715         /* This is calculated to be the largest file size for a dense, block
2716          * mapped file such that the file's total number of 512-byte sectors,
2717          * including data and all indirect blocks, does not exceed (2^48 - 1).
2718          *
2719          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2720          * number of 512-byte sectors of the file.
2721          */
2722
2723         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2724                 /*
2725                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2726                  * the inode i_block field represents total file blocks in
2727                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2728                  */
2729                 upper_limit = (1LL << 32) - 1;
2730
2731                 /* total blocks in file system block size */
2732                 upper_limit >>= (bits - 9);
2733
2734         } else {
2735                 /*
2736                  * We use 48 bit ext4_inode i_blocks
2737                  * With EXT4_HUGE_FILE_FL set the i_blocks
2738                  * represent total number of blocks in
2739                  * file system block size
2740                  */
2741                 upper_limit = (1LL << 48) - 1;
2742
2743         }
2744
2745         /* indirect blocks */
2746         meta_blocks = 1;
2747         /* double indirect blocks */
2748         meta_blocks += 1 + (1LL << (bits-2));
2749         /* tripple indirect blocks */
2750         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2751
2752         upper_limit -= meta_blocks;
2753         upper_limit <<= bits;
2754
2755         res += 1LL << (bits-2);
2756         res += 1LL << (2*(bits-2));
2757         res += 1LL << (3*(bits-2));
2758         res <<= bits;
2759         if (res > upper_limit)
2760                 res = upper_limit;
2761
2762         if (res > MAX_LFS_FILESIZE)
2763                 res = MAX_LFS_FILESIZE;
2764
2765         return res;
2766 }
2767
2768 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2769                                    ext4_fsblk_t logical_sb_block, int nr)
2770 {
2771         struct ext4_sb_info *sbi = EXT4_SB(sb);
2772         ext4_group_t bg, first_meta_bg;
2773         int has_super = 0;
2774
2775         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2776
2777         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2778                 return logical_sb_block + nr + 1;
2779         bg = sbi->s_desc_per_block * nr;
2780         if (ext4_bg_has_super(sb, bg))
2781                 has_super = 1;
2782
2783         /*
2784          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2785          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2786          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2787          * compensate.
2788          */
2789         if (sb->s_blocksize == 1024 && nr == 0 &&
2790             le32_to_cpu(sbi->s_es->s_first_data_block) == 0)
2791                 has_super++;
2792
2793         return (has_super + ext4_group_first_block_no(sb, bg));
2794 }
2795
2796 /**
2797  * ext4_get_stripe_size: Get the stripe size.
2798  * @sbi: In memory super block info
2799  *
2800  * If we have specified it via mount option, then
2801  * use the mount option value. If the value specified at mount time is
2802  * greater than the blocks per group use the super block value.
2803  * If the super block value is greater than blocks per group return 0.
2804  * Allocator needs it be less than blocks per group.
2805  *
2806  */
2807 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2808 {
2809         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2810         unsigned long stripe_width =
2811                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2812         int ret;
2813
2814         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2815                 ret = sbi->s_stripe;
2816         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2817                 ret = stripe_width;
2818         else if (stride && stride <= sbi->s_blocks_per_group)
2819                 ret = stride;
2820         else
2821                 ret = 0;
2822
2823         /*
2824          * If the stripe width is 1, this makes no sense and
2825          * we set it to 0 to turn off stripe handling code.
2826          */
2827         if (ret <= 1)
2828                 ret = 0;
2829
2830         return ret;
2831 }
2832
2833 /*
2834  * Check whether this filesystem can be mounted based on
2835  * the features present and the RDONLY/RDWR mount requested.
2836  * Returns 1 if this filesystem can be mounted as requested,
2837  * 0 if it cannot be.
2838  */
2839 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2840 {
2841         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2842                 ext4_msg(sb, KERN_ERR,
2843                         "Couldn't mount because of "
2844                         "unsupported optional features (%x)",
2845                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2846                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2847                 return 0;
2848         }
2849
2850         if (readonly)
2851                 return 1;
2852
2853         if (ext4_has_feature_readonly(sb)) {
2854                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2855                 sb->s_flags |= SB_RDONLY;
2856                 return 1;
2857         }
2858
2859         /* Check that feature set is OK for a read-write mount */
2860         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2861                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2862                          "unsupported optional features (%x)",
2863                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2864                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2865                 return 0;
2866         }
2867         /*
2868          * Large file size enabled file system can only be mounted
2869          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2870          */
2871         if (ext4_has_feature_huge_file(sb)) {
2872                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2873                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2874                                  "cannot be mounted RDWR without "
2875                                  "CONFIG_LBDAF");
2876                         return 0;
2877                 }
2878         }
2879         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2880                 ext4_msg(sb, KERN_ERR,
2881                          "Can't support bigalloc feature without "
2882                          "extents feature\n");
2883                 return 0;
2884         }
2885
2886 #ifndef CONFIG_QUOTA
2887         if (ext4_has_feature_quota(sb) && !readonly) {
2888                 ext4_msg(sb, KERN_ERR,
2889                          "Filesystem with quota feature cannot be mounted RDWR "
2890                          "without CONFIG_QUOTA");
2891                 return 0;
2892         }
2893         if (ext4_has_feature_project(sb) && !readonly) {
2894                 ext4_msg(sb, KERN_ERR,
2895                          "Filesystem with project quota feature cannot be mounted RDWR "
2896                          "without CONFIG_QUOTA");
2897                 return 0;
2898         }
2899 #endif  /* CONFIG_QUOTA */
2900         return 1;
2901 }
2902
2903 /*
2904  * This function is called once a day if we have errors logged
2905  * on the file system
2906  */
2907 static void print_daily_error_info(struct timer_list *t)
2908 {
2909         struct ext4_sb_info *sbi = from_timer(sbi, t, s_err_report);
2910         struct super_block *sb = sbi->s_sb;
2911         struct ext4_super_block *es = sbi->s_es;
2912
2913         if (es->s_error_count)
2914                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2915                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2916                          le32_to_cpu(es->s_error_count));
2917         if (es->s_first_error_time) {
2918                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %llu: %.*s:%d",
2919                        sb->s_id,
2920                        ext4_get_tstamp(es, s_first_error_time),
2921                        (int) sizeof(es->s_first_error_func),
2922                        es->s_first_error_func,
2923                        le32_to_cpu(es->s_first_error_line));
2924                 if (es->s_first_error_ino)
2925                         printk(KERN_CONT ": inode %u",
2926                                le32_to_cpu(es->s_first_error_ino));
2927                 if (es->s_first_error_block)
2928                         printk(KERN_CONT ": block %llu", (unsigned long long)
2929                                le64_to_cpu(es->s_first_error_block));
2930                 printk(KERN_CONT "\n");
2931         }
2932         if (es->s_last_error_time) {
2933                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %llu: %.*s:%d",
2934                        sb->s_id,
2935                        ext4_get_tstamp(es, s_last_error_time),
2936                        (int) sizeof(es->s_last_error_func),
2937                        es->s_last_error_func,
2938                        le32_to_cpu(es->s_last_error_line));
2939                 if (es->s_last_error_ino)
2940                         printk(KERN_CONT ": inode %u",
2941                                le32_to_cpu(es->s_last_error_ino));
2942                 if (es->s_last_error_block)
2943                         printk(KERN_CONT ": block %llu", (unsigned long long)
2944                                le64_to_cpu(es->s_last_error_block));
2945                 printk(KERN_CONT "\n");
2946         }
2947         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2948 }
2949
2950 /* Find next suitable group and run ext4_init_inode_table */
2951 static int ext4_run_li_request(struct ext4_li_request *elr)
2952 {
2953         struct ext4_group_desc *gdp = NULL;
2954         ext4_group_t group, ngroups;
2955         struct super_block *sb;
2956         unsigned long timeout = 0;
2957         int ret = 0;
2958
2959         sb = elr->lr_super;
2960         ngroups = EXT4_SB(sb)->s_groups_count;
2961
2962         for (group = elr->lr_next_group; group < ngroups; group++) {
2963                 gdp = ext4_get_group_desc(sb, group, NULL);
2964                 if (!gdp) {
2965                         ret = 1;
2966                         break;
2967                 }
2968
2969                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2970                         break;
2971         }
2972
2973         if (group >= ngroups)
2974                 ret = 1;
2975
2976         if (!ret) {
2977                 timeout = jiffies;
2978                 ret = ext4_init_inode_table(sb, group,
2979                                             elr->lr_timeout ? 0 : 1);
2980                 if (elr->lr_timeout == 0) {
2981                         timeout = (jiffies - timeout) *
2982                                   elr->lr_sbi->s_li_wait_mult;
2983                         elr->lr_timeout = timeout;
2984                 }
2985                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2986                 elr->lr_next_group = group + 1;
2987         }
2988         return ret;
2989 }
2990
2991 /*
2992  * Remove lr_request from the list_request and free the
2993  * request structure. Should be called with li_list_mtx held
2994  */
2995 static void ext4_remove_li_request(struct ext4_li_request *elr)
2996 {
2997         struct ext4_sb_info *sbi;
2998
2999         if (!elr)
3000                 return;
3001
3002         sbi = elr->lr_sbi;
3003
3004         list_del(&elr->lr_request);
3005         sbi->s_li_request = NULL;
3006         kfree(elr);
3007 }
3008
3009 static void ext4_unregister_li_request(struct super_block *sb)
3010 {
3011         mutex_lock(&ext4_li_mtx);
3012         if (!ext4_li_info) {
3013                 mutex_unlock(&ext4_li_mtx);
3014                 return;
3015         }
3016
3017         mutex_lock(&ext4_li_info->li_list_mtx);
3018         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
3019         mutex_unlock(&ext4_li_info->li_list_mtx);
3020         mutex_unlock(&ext4_li_mtx);
3021 }
3022
3023 static struct task_struct *ext4_lazyinit_task;
3024
3025 /*
3026  * This is the function where ext4lazyinit thread lives. It walks
3027  * through the request list searching for next scheduled filesystem.
3028  * When such a fs is found, run the lazy initialization request
3029  * (ext4_rn_li_request) and keep track of the time spend in this
3030  * function. Based on that time we compute next schedule time of
3031  * the request. When walking through the list is complete, compute
3032  * next waking time and put itself into sleep.
3033  */
3034 static int ext4_lazyinit_thread(void *arg)
3035 {
3036         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
3037         struct list_head *pos, *n;
3038         struct ext4_li_request *elr;
3039         unsigned long next_wakeup, cur;
3040
3041         BUG_ON(NULL == eli);
3042
3043 cont_thread:
3044         while (true) {
3045                 next_wakeup = MAX_JIFFY_OFFSET;
3046
3047                 mutex_lock(&eli->li_list_mtx);
3048                 if (list_empty(&eli->li_request_list)) {
3049                         mutex_unlock(&eli->li_list_mtx);
3050                         goto exit_thread;
3051                 }
3052                 list_for_each_safe(pos, n, &eli->li_request_list) {
3053                         int err = 0;
3054                         int progress = 0;
3055                         elr = list_entry(pos, struct ext4_li_request,
3056                                          lr_request);
3057
3058                         if (time_before(jiffies, elr->lr_next_sched)) {
3059                                 if (time_before(elr->lr_next_sched, next_wakeup))
3060                                         next_wakeup = elr->lr_next_sched;
3061                                 continue;
3062                         }
3063                         if (down_read_trylock(&elr->lr_super->s_umount)) {
3064                                 if (sb_start_write_trylock(elr->lr_super)) {
3065                                         progress = 1;
3066                                         /*
3067                                          * We hold sb->s_umount, sb can not
3068                                          * be removed from the list, it is
3069                                          * now safe to drop li_list_mtx
3070                                          */
3071                                         mutex_unlock(&eli->li_list_mtx);
3072                                         err = ext4_run_li_request(elr);
3073                                         sb_end_write(elr->lr_super);
3074                                         mutex_lock(&eli->li_list_mtx);
3075                                         n = pos->next;
3076                                 }
3077                                 up_read((&elr->lr_super->s_umount));
3078                         }
3079                         /* error, remove the lazy_init job */
3080                         if (err) {
3081                                 ext4_remove_li_request(elr);
3082                                 continue;
3083                         }
3084                         if (!progress) {
3085                                 elr->lr_next_sched = jiffies +
3086                                         (prandom_u32()
3087                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3088                         }
3089                         if (time_before(elr->lr_next_sched, next_wakeup))
3090                                 next_wakeup = elr->lr_next_sched;
3091                 }
3092                 mutex_unlock(&eli->li_list_mtx);
3093
3094                 try_to_freeze();
3095
3096                 cur = jiffies;
3097                 if ((time_after_eq(cur, next_wakeup)) ||
3098                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3099                         cond_resched();
3100                         continue;
3101                 }
3102
3103                 schedule_timeout_interruptible(next_wakeup - cur);
3104
3105                 if (kthread_should_stop()) {
3106                         ext4_clear_request_list();
3107                         goto exit_thread;
3108                 }
3109         }
3110
3111 exit_thread:
3112         /*
3113          * It looks like the request list is empty, but we need
3114          * to check it under the li_list_mtx lock, to prevent any
3115          * additions into it, and of course we should lock ext4_li_mtx
3116          * to atomically free the list and ext4_li_info, because at
3117          * this point another ext4 filesystem could be registering
3118          * new one.
3119          */
3120         mutex_lock(&ext4_li_mtx);
3121         mutex_lock(&eli->li_list_mtx);
3122         if (!list_empty(&eli->li_request_list)) {
3123                 mutex_unlock(&eli->li_list_mtx);
3124                 mutex_unlock(&ext4_li_mtx);
3125                 goto cont_thread;
3126         }
3127         mutex_unlock(&eli->li_list_mtx);
3128         kfree(ext4_li_info);
3129         ext4_li_info = NULL;
3130         mutex_unlock(&ext4_li_mtx);
3131
3132         return 0;
3133 }
3134
3135 static void ext4_clear_request_list(void)
3136 {
3137         struct list_head *pos, *n;
3138         struct ext4_li_request *elr;
3139
3140         mutex_lock(&ext4_li_info->li_list_mtx);
3141         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3142                 elr = list_entry(pos, struct ext4_li_request,
3143                                  lr_request);
3144                 ext4_remove_li_request(elr);
3145         }
3146         mutex_unlock(&ext4_li_info->li_list_mtx);
3147 }
3148
3149 static int ext4_run_lazyinit_thread(void)
3150 {
3151         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3152                                          ext4_li_info, "ext4lazyinit");
3153         if (IS_ERR(ext4_lazyinit_task)) {
3154                 int err = PTR_ERR(ext4_lazyinit_task);
3155                 ext4_clear_request_list();
3156                 kfree(ext4_li_info);
3157                 ext4_li_info = NULL;
3158                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3159                                  "initialization thread\n",
3160                                  err);
3161                 return err;
3162         }
3163         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3164         return 0;
3165 }
3166
3167 /*
3168  * Check whether it make sense to run itable init. thread or not.
3169  * If there is at least one uninitialized inode table, return
3170  * corresponding group number, else the loop goes through all
3171  * groups and return total number of groups.
3172  */
3173 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3174 {
3175         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3176         struct ext4_group_desc *gdp = NULL;
3177
3178         if (!ext4_has_group_desc_csum(sb))
3179                 return ngroups;
3180
3181         for (group = 0; group < ngroups; group++) {
3182                 gdp = ext4_get_group_desc(sb, group, NULL);
3183                 if (!gdp)
3184                         continue;
3185
3186                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3187                         break;
3188         }
3189
3190         return group;
3191 }
3192
3193 static int ext4_li_info_new(void)
3194 {
3195         struct ext4_lazy_init *eli = NULL;
3196
3197         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3198         if (!eli)
3199                 return -ENOMEM;
3200
3201         INIT_LIST_HEAD(&eli->li_request_list);
3202         mutex_init(&eli->li_list_mtx);
3203
3204         eli->li_state |= EXT4_LAZYINIT_QUIT;
3205
3206         ext4_li_info = eli;
3207
3208         return 0;
3209 }
3210
3211 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3212                                             ext4_group_t start)
3213 {