Merge branches 'arm/rockchip', 'arm/exynos', 'arm/smmu', 'x86/vt-d', 'x86/amd', ...
[sfrench/cifs-2.6.git] / fs / ext4 / super.c
1 /*
2  *  linux/fs/ext4/super.c
3  *
4  * Copyright (C) 1992, 1993, 1994, 1995
5  * Remy Card (card@masi.ibp.fr)
6  * Laboratoire MASI - Institut Blaise Pascal
7  * Universite Pierre et Marie Curie (Paris VI)
8  *
9  *  from
10  *
11  *  linux/fs/minix/inode.c
12  *
13  *  Copyright (C) 1991, 1992  Linus Torvalds
14  *
15  *  Big-endian to little-endian byte-swapping/bitmaps by
16  *        David S. Miller (davem@caip.rutgers.edu), 1995
17  */
18
19 #include <linux/module.h>
20 #include <linux/string.h>
21 #include <linux/fs.h>
22 #include <linux/time.h>
23 #include <linux/vmalloc.h>
24 #include <linux/slab.h>
25 #include <linux/init.h>
26 #include <linux/blkdev.h>
27 #include <linux/parser.h>
28 #include <linux/buffer_head.h>
29 #include <linux/exportfs.h>
30 #include <linux/vfs.h>
31 #include <linux/random.h>
32 #include <linux/mount.h>
33 #include <linux/namei.h>
34 #include <linux/quotaops.h>
35 #include <linux/seq_file.h>
36 #include <linux/proc_fs.h>
37 #include <linux/ctype.h>
38 #include <linux/log2.h>
39 #include <linux/crc16.h>
40 #include <linux/cleancache.h>
41 #include <asm/uaccess.h>
42
43 #include <linux/kthread.h>
44 #include <linux/freezer.h>
45
46 #include "ext4.h"
47 #include "ext4_extents.h"       /* Needed for trace points definition */
48 #include "ext4_jbd2.h"
49 #include "xattr.h"
50 #include "acl.h"
51 #include "mballoc.h"
52
53 #define CREATE_TRACE_POINTS
54 #include <trace/events/ext4.h>
55
56 static struct proc_dir_entry *ext4_proc_root;
57 static struct kset *ext4_kset;
58 static struct ext4_lazy_init *ext4_li_info;
59 static struct mutex ext4_li_mtx;
60 static struct ext4_features *ext4_feat;
61 static int ext4_mballoc_ready;
62
63 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
64                              unsigned long journal_devnum);
65 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
66 static int ext4_commit_super(struct super_block *sb, int sync);
67 static void ext4_mark_recovery_complete(struct super_block *sb,
68                                         struct ext4_super_block *es);
69 static void ext4_clear_journal_err(struct super_block *sb,
70                                    struct ext4_super_block *es);
71 static int ext4_sync_fs(struct super_block *sb, int wait);
72 static int ext4_remount(struct super_block *sb, int *flags, char *data);
73 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
74 static int ext4_unfreeze(struct super_block *sb);
75 static int ext4_freeze(struct super_block *sb);
76 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
77                        const char *dev_name, void *data);
78 static inline int ext2_feature_set_ok(struct super_block *sb);
79 static inline int ext3_feature_set_ok(struct super_block *sb);
80 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
81 static void ext4_destroy_lazyinit_thread(void);
82 static void ext4_unregister_li_request(struct super_block *sb);
83 static void ext4_clear_request_list(void);
84 static int ext4_reserve_clusters(struct ext4_sb_info *, ext4_fsblk_t);
85
86 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
87 static struct file_system_type ext2_fs_type = {
88         .owner          = THIS_MODULE,
89         .name           = "ext2",
90         .mount          = ext4_mount,
91         .kill_sb        = kill_block_super,
92         .fs_flags       = FS_REQUIRES_DEV,
93 };
94 MODULE_ALIAS_FS("ext2");
95 MODULE_ALIAS("ext2");
96 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
97 #else
98 #define IS_EXT2_SB(sb) (0)
99 #endif
100
101
102 #if !defined(CONFIG_EXT3_FS) && !defined(CONFIG_EXT3_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT23)
103 static struct file_system_type ext3_fs_type = {
104         .owner          = THIS_MODULE,
105         .name           = "ext3",
106         .mount          = ext4_mount,
107         .kill_sb        = kill_block_super,
108         .fs_flags       = FS_REQUIRES_DEV,
109 };
110 MODULE_ALIAS_FS("ext3");
111 MODULE_ALIAS("ext3");
112 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
113 #else
114 #define IS_EXT3_SB(sb) (0)
115 #endif
116
117 static int ext4_verify_csum_type(struct super_block *sb,
118                                  struct ext4_super_block *es)
119 {
120         if (!EXT4_HAS_RO_COMPAT_FEATURE(sb,
121                                         EXT4_FEATURE_RO_COMPAT_METADATA_CSUM))
122                 return 1;
123
124         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
125 }
126
127 static __le32 ext4_superblock_csum(struct super_block *sb,
128                                    struct ext4_super_block *es)
129 {
130         struct ext4_sb_info *sbi = EXT4_SB(sb);
131         int offset = offsetof(struct ext4_super_block, s_checksum);
132         __u32 csum;
133
134         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
135
136         return cpu_to_le32(csum);
137 }
138
139 static int ext4_superblock_csum_verify(struct super_block *sb,
140                                        struct ext4_super_block *es)
141 {
142         if (!ext4_has_metadata_csum(sb))
143                 return 1;
144
145         return es->s_checksum == ext4_superblock_csum(sb, es);
146 }
147
148 void ext4_superblock_csum_set(struct super_block *sb)
149 {
150         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
151
152         if (!ext4_has_metadata_csum(sb))
153                 return;
154
155         es->s_checksum = ext4_superblock_csum(sb, es);
156 }
157
158 void *ext4_kvmalloc(size_t size, gfp_t flags)
159 {
160         void *ret;
161
162         ret = kmalloc(size, flags | __GFP_NOWARN);
163         if (!ret)
164                 ret = __vmalloc(size, flags, PAGE_KERNEL);
165         return ret;
166 }
167
168 void *ext4_kvzalloc(size_t size, gfp_t flags)
169 {
170         void *ret;
171
172         ret = kzalloc(size, flags | __GFP_NOWARN);
173         if (!ret)
174                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
175         return ret;
176 }
177
178 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
179                                struct ext4_group_desc *bg)
180 {
181         return le32_to_cpu(bg->bg_block_bitmap_lo) |
182                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
183                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
184 }
185
186 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
187                                struct ext4_group_desc *bg)
188 {
189         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
190                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
191                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
192 }
193
194 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
195                               struct ext4_group_desc *bg)
196 {
197         return le32_to_cpu(bg->bg_inode_table_lo) |
198                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
199                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
200 }
201
202 __u32 ext4_free_group_clusters(struct super_block *sb,
203                                struct ext4_group_desc *bg)
204 {
205         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
206                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
207                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
208 }
209
210 __u32 ext4_free_inodes_count(struct super_block *sb,
211                               struct ext4_group_desc *bg)
212 {
213         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
214                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
215                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
216 }
217
218 __u32 ext4_used_dirs_count(struct super_block *sb,
219                               struct ext4_group_desc *bg)
220 {
221         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
222                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
223                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
224 }
225
226 __u32 ext4_itable_unused_count(struct super_block *sb,
227                               struct ext4_group_desc *bg)
228 {
229         return le16_to_cpu(bg->bg_itable_unused_lo) |
230                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
231                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
232 }
233
234 void ext4_block_bitmap_set(struct super_block *sb,
235                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
236 {
237         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
238         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
239                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
240 }
241
242 void ext4_inode_bitmap_set(struct super_block *sb,
243                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
244 {
245         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
246         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
247                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
248 }
249
250 void ext4_inode_table_set(struct super_block *sb,
251                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
252 {
253         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
254         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
255                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
256 }
257
258 void ext4_free_group_clusters_set(struct super_block *sb,
259                                   struct ext4_group_desc *bg, __u32 count)
260 {
261         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
262         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
263                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
264 }
265
266 void ext4_free_inodes_set(struct super_block *sb,
267                           struct ext4_group_desc *bg, __u32 count)
268 {
269         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
270         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
271                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
272 }
273
274 void ext4_used_dirs_set(struct super_block *sb,
275                           struct ext4_group_desc *bg, __u32 count)
276 {
277         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
278         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
279                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
280 }
281
282 void ext4_itable_unused_set(struct super_block *sb,
283                           struct ext4_group_desc *bg, __u32 count)
284 {
285         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
286         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
287                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
288 }
289
290
291 static void __save_error_info(struct super_block *sb, const char *func,
292                             unsigned int line)
293 {
294         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
295
296         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
297         if (bdev_read_only(sb->s_bdev))
298                 return;
299         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
300         es->s_last_error_time = cpu_to_le32(get_seconds());
301         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
302         es->s_last_error_line = cpu_to_le32(line);
303         if (!es->s_first_error_time) {
304                 es->s_first_error_time = es->s_last_error_time;
305                 strncpy(es->s_first_error_func, func,
306                         sizeof(es->s_first_error_func));
307                 es->s_first_error_line = cpu_to_le32(line);
308                 es->s_first_error_ino = es->s_last_error_ino;
309                 es->s_first_error_block = es->s_last_error_block;
310         }
311         /*
312          * Start the daily error reporting function if it hasn't been
313          * started already
314          */
315         if (!es->s_error_count)
316                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
317         le32_add_cpu(&es->s_error_count, 1);
318 }
319
320 static void save_error_info(struct super_block *sb, const char *func,
321                             unsigned int line)
322 {
323         __save_error_info(sb, func, line);
324         ext4_commit_super(sb, 1);
325 }
326
327 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
328 {
329         struct super_block              *sb = journal->j_private;
330         struct ext4_sb_info             *sbi = EXT4_SB(sb);
331         int                             error = is_journal_aborted(journal);
332         struct ext4_journal_cb_entry    *jce;
333
334         BUG_ON(txn->t_state == T_FINISHED);
335         spin_lock(&sbi->s_md_lock);
336         while (!list_empty(&txn->t_private_list)) {
337                 jce = list_entry(txn->t_private_list.next,
338                                  struct ext4_journal_cb_entry, jce_list);
339                 list_del_init(&jce->jce_list);
340                 spin_unlock(&sbi->s_md_lock);
341                 jce->jce_func(sb, jce, error);
342                 spin_lock(&sbi->s_md_lock);
343         }
344         spin_unlock(&sbi->s_md_lock);
345 }
346
347 /* Deal with the reporting of failure conditions on a filesystem such as
348  * inconsistencies detected or read IO failures.
349  *
350  * On ext2, we can store the error state of the filesystem in the
351  * superblock.  That is not possible on ext4, because we may have other
352  * write ordering constraints on the superblock which prevent us from
353  * writing it out straight away; and given that the journal is about to
354  * be aborted, we can't rely on the current, or future, transactions to
355  * write out the superblock safely.
356  *
357  * We'll just use the jbd2_journal_abort() error code to record an error in
358  * the journal instead.  On recovery, the journal will complain about
359  * that error until we've noted it down and cleared it.
360  */
361
362 static void ext4_handle_error(struct super_block *sb)
363 {
364         if (sb->s_flags & MS_RDONLY)
365                 return;
366
367         if (!test_opt(sb, ERRORS_CONT)) {
368                 journal_t *journal = EXT4_SB(sb)->s_journal;
369
370                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
371                 if (journal)
372                         jbd2_journal_abort(journal, -EIO);
373         }
374         if (test_opt(sb, ERRORS_RO)) {
375                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
376                 /*
377                  * Make sure updated value of ->s_mount_flags will be visible
378                  * before ->s_flags update
379                  */
380                 smp_wmb();
381                 sb->s_flags |= MS_RDONLY;
382         }
383         if (test_opt(sb, ERRORS_PANIC))
384                 panic("EXT4-fs (device %s): panic forced after error\n",
385                         sb->s_id);
386 }
387
388 #define ext4_error_ratelimit(sb)                                        \
389                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
390                              "EXT4-fs error")
391
392 void __ext4_error(struct super_block *sb, const char *function,
393                   unsigned int line, const char *fmt, ...)
394 {
395         struct va_format vaf;
396         va_list args;
397
398         if (ext4_error_ratelimit(sb)) {
399                 va_start(args, fmt);
400                 vaf.fmt = fmt;
401                 vaf.va = &args;
402                 printk(KERN_CRIT
403                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
404                        sb->s_id, function, line, current->comm, &vaf);
405                 va_end(args);
406         }
407         save_error_info(sb, function, line);
408         ext4_handle_error(sb);
409 }
410
411 void __ext4_error_inode(struct inode *inode, const char *function,
412                         unsigned int line, ext4_fsblk_t block,
413                         const char *fmt, ...)
414 {
415         va_list args;
416         struct va_format vaf;
417         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
418
419         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
420         es->s_last_error_block = cpu_to_le64(block);
421         if (ext4_error_ratelimit(inode->i_sb)) {
422                 va_start(args, fmt);
423                 vaf.fmt = fmt;
424                 vaf.va = &args;
425                 if (block)
426                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
427                                "inode #%lu: block %llu: comm %s: %pV\n",
428                                inode->i_sb->s_id, function, line, inode->i_ino,
429                                block, current->comm, &vaf);
430                 else
431                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
432                                "inode #%lu: comm %s: %pV\n",
433                                inode->i_sb->s_id, function, line, inode->i_ino,
434                                current->comm, &vaf);
435                 va_end(args);
436         }
437         save_error_info(inode->i_sb, function, line);
438         ext4_handle_error(inode->i_sb);
439 }
440
441 void __ext4_error_file(struct file *file, const char *function,
442                        unsigned int line, ext4_fsblk_t block,
443                        const char *fmt, ...)
444 {
445         va_list args;
446         struct va_format vaf;
447         struct ext4_super_block *es;
448         struct inode *inode = file_inode(file);
449         char pathname[80], *path;
450
451         es = EXT4_SB(inode->i_sb)->s_es;
452         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
453         if (ext4_error_ratelimit(inode->i_sb)) {
454                 path = d_path(&(file->f_path), pathname, sizeof(pathname));
455                 if (IS_ERR(path))
456                         path = "(unknown)";
457                 va_start(args, fmt);
458                 vaf.fmt = fmt;
459                 vaf.va = &args;
460                 if (block)
461                         printk(KERN_CRIT
462                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
463                                "block %llu: comm %s: path %s: %pV\n",
464                                inode->i_sb->s_id, function, line, inode->i_ino,
465                                block, current->comm, path, &vaf);
466                 else
467                         printk(KERN_CRIT
468                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
469                                "comm %s: path %s: %pV\n",
470                                inode->i_sb->s_id, function, line, inode->i_ino,
471                                current->comm, path, &vaf);
472                 va_end(args);
473         }
474         save_error_info(inode->i_sb, function, line);
475         ext4_handle_error(inode->i_sb);
476 }
477
478 const char *ext4_decode_error(struct super_block *sb, int errno,
479                               char nbuf[16])
480 {
481         char *errstr = NULL;
482
483         switch (errno) {
484         case -EIO:
485                 errstr = "IO failure";
486                 break;
487         case -ENOMEM:
488                 errstr = "Out of memory";
489                 break;
490         case -EROFS:
491                 if (!sb || (EXT4_SB(sb)->s_journal &&
492                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
493                         errstr = "Journal has aborted";
494                 else
495                         errstr = "Readonly filesystem";
496                 break;
497         default:
498                 /* If the caller passed in an extra buffer for unknown
499                  * errors, textualise them now.  Else we just return
500                  * NULL. */
501                 if (nbuf) {
502                         /* Check for truncated error codes... */
503                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
504                                 errstr = nbuf;
505                 }
506                 break;
507         }
508
509         return errstr;
510 }
511
512 /* __ext4_std_error decodes expected errors from journaling functions
513  * automatically and invokes the appropriate error response.  */
514
515 void __ext4_std_error(struct super_block *sb, const char *function,
516                       unsigned int line, int errno)
517 {
518         char nbuf[16];
519         const char *errstr;
520
521         /* Special case: if the error is EROFS, and we're not already
522          * inside a transaction, then there's really no point in logging
523          * an error. */
524         if (errno == -EROFS && journal_current_handle() == NULL &&
525             (sb->s_flags & MS_RDONLY))
526                 return;
527
528         if (ext4_error_ratelimit(sb)) {
529                 errstr = ext4_decode_error(sb, errno, nbuf);
530                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
531                        sb->s_id, function, line, errstr);
532         }
533
534         save_error_info(sb, function, line);
535         ext4_handle_error(sb);
536 }
537
538 /*
539  * ext4_abort is a much stronger failure handler than ext4_error.  The
540  * abort function may be used to deal with unrecoverable failures such
541  * as journal IO errors or ENOMEM at a critical moment in log management.
542  *
543  * We unconditionally force the filesystem into an ABORT|READONLY state,
544  * unless the error response on the fs has been set to panic in which
545  * case we take the easy way out and panic immediately.
546  */
547
548 void __ext4_abort(struct super_block *sb, const char *function,
549                 unsigned int line, const char *fmt, ...)
550 {
551         va_list args;
552
553         save_error_info(sb, function, line);
554         va_start(args, fmt);
555         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: ", sb->s_id,
556                function, line);
557         vprintk(fmt, args);
558         printk("\n");
559         va_end(args);
560
561         if ((sb->s_flags & MS_RDONLY) == 0) {
562                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
563                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
564                 /*
565                  * Make sure updated value of ->s_mount_flags will be visible
566                  * before ->s_flags update
567                  */
568                 smp_wmb();
569                 sb->s_flags |= MS_RDONLY;
570                 if (EXT4_SB(sb)->s_journal)
571                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
572                 save_error_info(sb, function, line);
573         }
574         if (test_opt(sb, ERRORS_PANIC))
575                 panic("EXT4-fs panic from previous error\n");
576 }
577
578 void __ext4_msg(struct super_block *sb,
579                 const char *prefix, const char *fmt, ...)
580 {
581         struct va_format vaf;
582         va_list args;
583
584         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
585                 return;
586
587         va_start(args, fmt);
588         vaf.fmt = fmt;
589         vaf.va = &args;
590         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
591         va_end(args);
592 }
593
594 void __ext4_warning(struct super_block *sb, const char *function,
595                     unsigned int line, const char *fmt, ...)
596 {
597         struct va_format vaf;
598         va_list args;
599
600         if (!___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state),
601                           "EXT4-fs warning"))
602                 return;
603
604         va_start(args, fmt);
605         vaf.fmt = fmt;
606         vaf.va = &args;
607         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
608                sb->s_id, function, line, &vaf);
609         va_end(args);
610 }
611
612 void __ext4_grp_locked_error(const char *function, unsigned int line,
613                              struct super_block *sb, ext4_group_t grp,
614                              unsigned long ino, ext4_fsblk_t block,
615                              const char *fmt, ...)
616 __releases(bitlock)
617 __acquires(bitlock)
618 {
619         struct va_format vaf;
620         va_list args;
621         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
622
623         es->s_last_error_ino = cpu_to_le32(ino);
624         es->s_last_error_block = cpu_to_le64(block);
625         __save_error_info(sb, function, line);
626
627         if (ext4_error_ratelimit(sb)) {
628                 va_start(args, fmt);
629                 vaf.fmt = fmt;
630                 vaf.va = &args;
631                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
632                        sb->s_id, function, line, grp);
633                 if (ino)
634                         printk(KERN_CONT "inode %lu: ", ino);
635                 if (block)
636                         printk(KERN_CONT "block %llu:",
637                                (unsigned long long) block);
638                 printk(KERN_CONT "%pV\n", &vaf);
639                 va_end(args);
640         }
641
642         if (test_opt(sb, ERRORS_CONT)) {
643                 ext4_commit_super(sb, 0);
644                 return;
645         }
646
647         ext4_unlock_group(sb, grp);
648         ext4_handle_error(sb);
649         /*
650          * We only get here in the ERRORS_RO case; relocking the group
651          * may be dangerous, but nothing bad will happen since the
652          * filesystem will have already been marked read/only and the
653          * journal has been aborted.  We return 1 as a hint to callers
654          * who might what to use the return value from
655          * ext4_grp_locked_error() to distinguish between the
656          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
657          * aggressively from the ext4 function in question, with a
658          * more appropriate error code.
659          */
660         ext4_lock_group(sb, grp);
661         return;
662 }
663
664 void ext4_update_dynamic_rev(struct super_block *sb)
665 {
666         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
667
668         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
669                 return;
670
671         ext4_warning(sb,
672                      "updating to rev %d because of new feature flag, "
673                      "running e2fsck is recommended",
674                      EXT4_DYNAMIC_REV);
675
676         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
677         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
678         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
679         /* leave es->s_feature_*compat flags alone */
680         /* es->s_uuid will be set by e2fsck if empty */
681
682         /*
683          * The rest of the superblock fields should be zero, and if not it
684          * means they are likely already in use, so leave them alone.  We
685          * can leave it up to e2fsck to clean up any inconsistencies there.
686          */
687 }
688
689 /*
690  * Open the external journal device
691  */
692 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
693 {
694         struct block_device *bdev;
695         char b[BDEVNAME_SIZE];
696
697         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
698         if (IS_ERR(bdev))
699                 goto fail;
700         return bdev;
701
702 fail:
703         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
704                         __bdevname(dev, b), PTR_ERR(bdev));
705         return NULL;
706 }
707
708 /*
709  * Release the journal device
710  */
711 static void ext4_blkdev_put(struct block_device *bdev)
712 {
713         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
714 }
715
716 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
717 {
718         struct block_device *bdev;
719         bdev = sbi->journal_bdev;
720         if (bdev) {
721                 ext4_blkdev_put(bdev);
722                 sbi->journal_bdev = NULL;
723         }
724 }
725
726 static inline struct inode *orphan_list_entry(struct list_head *l)
727 {
728         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
729 }
730
731 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
732 {
733         struct list_head *l;
734
735         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
736                  le32_to_cpu(sbi->s_es->s_last_orphan));
737
738         printk(KERN_ERR "sb_info orphan list:\n");
739         list_for_each(l, &sbi->s_orphan) {
740                 struct inode *inode = orphan_list_entry(l);
741                 printk(KERN_ERR "  "
742                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
743                        inode->i_sb->s_id, inode->i_ino, inode,
744                        inode->i_mode, inode->i_nlink,
745                        NEXT_ORPHAN(inode));
746         }
747 }
748
749 static void ext4_put_super(struct super_block *sb)
750 {
751         struct ext4_sb_info *sbi = EXT4_SB(sb);
752         struct ext4_super_block *es = sbi->s_es;
753         int i, err;
754
755         ext4_unregister_li_request(sb);
756         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
757
758         flush_workqueue(sbi->rsv_conversion_wq);
759         destroy_workqueue(sbi->rsv_conversion_wq);
760
761         if (sbi->s_journal) {
762                 err = jbd2_journal_destroy(sbi->s_journal);
763                 sbi->s_journal = NULL;
764                 if (err < 0)
765                         ext4_abort(sb, "Couldn't clean up the journal");
766         }
767
768         ext4_es_unregister_shrinker(sbi);
769         del_timer_sync(&sbi->s_err_report);
770         ext4_release_system_zone(sb);
771         ext4_mb_release(sb);
772         ext4_ext_release(sb);
773         ext4_xattr_put_super(sb);
774
775         if (!(sb->s_flags & MS_RDONLY)) {
776                 EXT4_CLEAR_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
777                 es->s_state = cpu_to_le16(sbi->s_mount_state);
778         }
779         if (!(sb->s_flags & MS_RDONLY))
780                 ext4_commit_super(sb, 1);
781
782         if (sbi->s_proc) {
783                 remove_proc_entry("options", sbi->s_proc);
784                 remove_proc_entry(sb->s_id, ext4_proc_root);
785         }
786         kobject_del(&sbi->s_kobj);
787
788         for (i = 0; i < sbi->s_gdb_count; i++)
789                 brelse(sbi->s_group_desc[i]);
790         kvfree(sbi->s_group_desc);
791         kvfree(sbi->s_flex_groups);
792         percpu_counter_destroy(&sbi->s_freeclusters_counter);
793         percpu_counter_destroy(&sbi->s_freeinodes_counter);
794         percpu_counter_destroy(&sbi->s_dirs_counter);
795         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
796         brelse(sbi->s_sbh);
797 #ifdef CONFIG_QUOTA
798         for (i = 0; i < EXT4_MAXQUOTAS; i++)
799                 kfree(sbi->s_qf_names[i]);
800 #endif
801
802         /* Debugging code just in case the in-memory inode orphan list
803          * isn't empty.  The on-disk one can be non-empty if we've
804          * detected an error and taken the fs readonly, but the
805          * in-memory list had better be clean by this point. */
806         if (!list_empty(&sbi->s_orphan))
807                 dump_orphan_list(sb, sbi);
808         J_ASSERT(list_empty(&sbi->s_orphan));
809
810         invalidate_bdev(sb->s_bdev);
811         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
812                 /*
813                  * Invalidate the journal device's buffers.  We don't want them
814                  * floating about in memory - the physical journal device may
815                  * hotswapped, and it breaks the `ro-after' testing code.
816                  */
817                 sync_blockdev(sbi->journal_bdev);
818                 invalidate_bdev(sbi->journal_bdev);
819                 ext4_blkdev_remove(sbi);
820         }
821         if (sbi->s_mb_cache) {
822                 ext4_xattr_destroy_cache(sbi->s_mb_cache);
823                 sbi->s_mb_cache = NULL;
824         }
825         if (sbi->s_mmp_tsk)
826                 kthread_stop(sbi->s_mmp_tsk);
827         sb->s_fs_info = NULL;
828         /*
829          * Now that we are completely done shutting down the
830          * superblock, we need to actually destroy the kobject.
831          */
832         kobject_put(&sbi->s_kobj);
833         wait_for_completion(&sbi->s_kobj_unregister);
834         if (sbi->s_chksum_driver)
835                 crypto_free_shash(sbi->s_chksum_driver);
836         kfree(sbi->s_blockgroup_lock);
837         kfree(sbi);
838 }
839
840 static struct kmem_cache *ext4_inode_cachep;
841
842 /*
843  * Called inside transaction, so use GFP_NOFS
844  */
845 static struct inode *ext4_alloc_inode(struct super_block *sb)
846 {
847         struct ext4_inode_info *ei;
848
849         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
850         if (!ei)
851                 return NULL;
852
853         ei->vfs_inode.i_version = 1;
854         spin_lock_init(&ei->i_raw_lock);
855         INIT_LIST_HEAD(&ei->i_prealloc_list);
856         spin_lock_init(&ei->i_prealloc_lock);
857         ext4_es_init_tree(&ei->i_es_tree);
858         rwlock_init(&ei->i_es_lock);
859         INIT_LIST_HEAD(&ei->i_es_list);
860         ei->i_es_all_nr = 0;
861         ei->i_es_shk_nr = 0;
862         ei->i_es_shrink_lblk = 0;
863         ei->i_reserved_data_blocks = 0;
864         ei->i_reserved_meta_blocks = 0;
865         ei->i_allocated_meta_blocks = 0;
866         ei->i_da_metadata_calc_len = 0;
867         ei->i_da_metadata_calc_last_lblock = 0;
868         spin_lock_init(&(ei->i_block_reservation_lock));
869 #ifdef CONFIG_QUOTA
870         ei->i_reserved_quota = 0;
871         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
872 #endif
873         ei->jinode = NULL;
874         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
875         spin_lock_init(&ei->i_completed_io_lock);
876         ei->i_sync_tid = 0;
877         ei->i_datasync_tid = 0;
878         atomic_set(&ei->i_ioend_count, 0);
879         atomic_set(&ei->i_unwritten, 0);
880         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
881 #ifdef CONFIG_EXT4_FS_ENCRYPTION
882         ei->i_encryption_key.mode = EXT4_ENCRYPTION_MODE_INVALID;
883 #endif
884
885         return &ei->vfs_inode;
886 }
887
888 static int ext4_drop_inode(struct inode *inode)
889 {
890         int drop = generic_drop_inode(inode);
891
892         trace_ext4_drop_inode(inode, drop);
893         return drop;
894 }
895
896 static void ext4_i_callback(struct rcu_head *head)
897 {
898         struct inode *inode = container_of(head, struct inode, i_rcu);
899         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
900 }
901
902 static void ext4_destroy_inode(struct inode *inode)
903 {
904         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
905                 ext4_msg(inode->i_sb, KERN_ERR,
906                          "Inode %lu (%p): orphan list check failed!",
907                          inode->i_ino, EXT4_I(inode));
908                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
909                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
910                                 true);
911                 dump_stack();
912         }
913         call_rcu(&inode->i_rcu, ext4_i_callback);
914 }
915
916 static void init_once(void *foo)
917 {
918         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
919
920         INIT_LIST_HEAD(&ei->i_orphan);
921         init_rwsem(&ei->xattr_sem);
922         init_rwsem(&ei->i_data_sem);
923         inode_init_once(&ei->vfs_inode);
924 }
925
926 static int __init init_inodecache(void)
927 {
928         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
929                                              sizeof(struct ext4_inode_info),
930                                              0, (SLAB_RECLAIM_ACCOUNT|
931                                                 SLAB_MEM_SPREAD),
932                                              init_once);
933         if (ext4_inode_cachep == NULL)
934                 return -ENOMEM;
935         return 0;
936 }
937
938 static void destroy_inodecache(void)
939 {
940         /*
941          * Make sure all delayed rcu free inodes are flushed before we
942          * destroy cache.
943          */
944         rcu_barrier();
945         kmem_cache_destroy(ext4_inode_cachep);
946 }
947
948 void ext4_clear_inode(struct inode *inode)
949 {
950         invalidate_inode_buffers(inode);
951         clear_inode(inode);
952         dquot_drop(inode);
953         ext4_discard_preallocations(inode);
954         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
955         if (EXT4_I(inode)->jinode) {
956                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
957                                                EXT4_I(inode)->jinode);
958                 jbd2_free_inode(EXT4_I(inode)->jinode);
959                 EXT4_I(inode)->jinode = NULL;
960         }
961 }
962
963 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
964                                         u64 ino, u32 generation)
965 {
966         struct inode *inode;
967
968         if (ino < EXT4_FIRST_INO(sb) && ino != EXT4_ROOT_INO)
969                 return ERR_PTR(-ESTALE);
970         if (ino > le32_to_cpu(EXT4_SB(sb)->s_es->s_inodes_count))
971                 return ERR_PTR(-ESTALE);
972
973         /* iget isn't really right if the inode is currently unallocated!!
974          *
975          * ext4_read_inode will return a bad_inode if the inode had been
976          * deleted, so we should be safe.
977          *
978          * Currently we don't know the generation for parent directory, so
979          * a generation of 0 means "accept any"
980          */
981         inode = ext4_iget_normal(sb, ino);
982         if (IS_ERR(inode))
983                 return ERR_CAST(inode);
984         if (generation && inode->i_generation != generation) {
985                 iput(inode);
986                 return ERR_PTR(-ESTALE);
987         }
988
989         return inode;
990 }
991
992 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
993                                         int fh_len, int fh_type)
994 {
995         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
996                                     ext4_nfs_get_inode);
997 }
998
999 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1000                                         int fh_len, int fh_type)
1001 {
1002         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1003                                     ext4_nfs_get_inode);
1004 }
1005
1006 /*
1007  * Try to release metadata pages (indirect blocks, directories) which are
1008  * mapped via the block device.  Since these pages could have journal heads
1009  * which would prevent try_to_free_buffers() from freeing them, we must use
1010  * jbd2 layer's try_to_free_buffers() function to release them.
1011  */
1012 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1013                                  gfp_t wait)
1014 {
1015         journal_t *journal = EXT4_SB(sb)->s_journal;
1016
1017         WARN_ON(PageChecked(page));
1018         if (!page_has_buffers(page))
1019                 return 0;
1020         if (journal)
1021                 return jbd2_journal_try_to_free_buffers(journal, page,
1022                                                         wait & ~__GFP_WAIT);
1023         return try_to_free_buffers(page);
1024 }
1025
1026 #ifdef CONFIG_QUOTA
1027 #define QTYPE2NAME(t) ((t) == USRQUOTA ? "user" : "group")
1028 #define QTYPE2MOPT(on, t) ((t) == USRQUOTA?((on)##USRJQUOTA):((on)##GRPJQUOTA))
1029
1030 static int ext4_write_dquot(struct dquot *dquot);
1031 static int ext4_acquire_dquot(struct dquot *dquot);
1032 static int ext4_release_dquot(struct dquot *dquot);
1033 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1034 static int ext4_write_info(struct super_block *sb, int type);
1035 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1036                          struct path *path);
1037 static int ext4_quota_off(struct super_block *sb, int type);
1038 static int ext4_quota_on_mount(struct super_block *sb, int type);
1039 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1040                                size_t len, loff_t off);
1041 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1042                                 const char *data, size_t len, loff_t off);
1043 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1044                              unsigned int flags);
1045 static int ext4_enable_quotas(struct super_block *sb);
1046
1047 static struct dquot **ext4_get_dquots(struct inode *inode)
1048 {
1049         return EXT4_I(inode)->i_dquot;
1050 }
1051
1052 static const struct dquot_operations ext4_quota_operations = {
1053         .get_reserved_space = ext4_get_reserved_space,
1054         .write_dquot    = ext4_write_dquot,
1055         .acquire_dquot  = ext4_acquire_dquot,
1056         .release_dquot  = ext4_release_dquot,
1057         .mark_dirty     = ext4_mark_dquot_dirty,
1058         .write_info     = ext4_write_info,
1059         .alloc_dquot    = dquot_alloc,
1060         .destroy_dquot  = dquot_destroy,
1061 };
1062
1063 static const struct quotactl_ops ext4_qctl_operations = {
1064         .quota_on       = ext4_quota_on,
1065         .quota_off      = ext4_quota_off,
1066         .quota_sync     = dquot_quota_sync,
1067         .get_state      = dquot_get_state,
1068         .set_info       = dquot_set_dqinfo,
1069         .get_dqblk      = dquot_get_dqblk,
1070         .set_dqblk      = dquot_set_dqblk
1071 };
1072 #endif
1073
1074 static const struct super_operations ext4_sops = {
1075         .alloc_inode    = ext4_alloc_inode,
1076         .destroy_inode  = ext4_destroy_inode,
1077         .write_inode    = ext4_write_inode,
1078         .dirty_inode    = ext4_dirty_inode,
1079         .drop_inode     = ext4_drop_inode,
1080         .evict_inode    = ext4_evict_inode,
1081         .put_super      = ext4_put_super,
1082         .sync_fs        = ext4_sync_fs,
1083         .freeze_fs      = ext4_freeze,
1084         .unfreeze_fs    = ext4_unfreeze,
1085         .statfs         = ext4_statfs,
1086         .remount_fs     = ext4_remount,
1087         .show_options   = ext4_show_options,
1088 #ifdef CONFIG_QUOTA
1089         .quota_read     = ext4_quota_read,
1090         .quota_write    = ext4_quota_write,
1091         .get_dquots     = ext4_get_dquots,
1092 #endif
1093         .bdev_try_to_free_page = bdev_try_to_free_page,
1094 };
1095
1096 static const struct export_operations ext4_export_ops = {
1097         .fh_to_dentry = ext4_fh_to_dentry,
1098         .fh_to_parent = ext4_fh_to_parent,
1099         .get_parent = ext4_get_parent,
1100 };
1101
1102 enum {
1103         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1104         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1105         Opt_nouid32, Opt_debug, Opt_removed,
1106         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1107         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1108         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1109         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1110         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1111         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1112         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1113         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1114         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1115         Opt_usrquota, Opt_grpquota, Opt_i_version, Opt_dax,
1116         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1117         Opt_lazytime, Opt_nolazytime,
1118         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1119         Opt_inode_readahead_blks, Opt_journal_ioprio,
1120         Opt_dioread_nolock, Opt_dioread_lock,
1121         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1122         Opt_max_dir_size_kb, Opt_nojournal_checksum,
1123 };
1124
1125 static const match_table_t tokens = {
1126         {Opt_bsd_df, "bsddf"},
1127         {Opt_minix_df, "minixdf"},
1128         {Opt_grpid, "grpid"},
1129         {Opt_grpid, "bsdgroups"},
1130         {Opt_nogrpid, "nogrpid"},
1131         {Opt_nogrpid, "sysvgroups"},
1132         {Opt_resgid, "resgid=%u"},
1133         {Opt_resuid, "resuid=%u"},
1134         {Opt_sb, "sb=%u"},
1135         {Opt_err_cont, "errors=continue"},
1136         {Opt_err_panic, "errors=panic"},
1137         {Opt_err_ro, "errors=remount-ro"},
1138         {Opt_nouid32, "nouid32"},
1139         {Opt_debug, "debug"},
1140         {Opt_removed, "oldalloc"},
1141         {Opt_removed, "orlov"},
1142         {Opt_user_xattr, "user_xattr"},
1143         {Opt_nouser_xattr, "nouser_xattr"},
1144         {Opt_acl, "acl"},
1145         {Opt_noacl, "noacl"},
1146         {Opt_noload, "norecovery"},
1147         {Opt_noload, "noload"},
1148         {Opt_removed, "nobh"},
1149         {Opt_removed, "bh"},
1150         {Opt_commit, "commit=%u"},
1151         {Opt_min_batch_time, "min_batch_time=%u"},
1152         {Opt_max_batch_time, "max_batch_time=%u"},
1153         {Opt_journal_dev, "journal_dev=%u"},
1154         {Opt_journal_path, "journal_path=%s"},
1155         {Opt_journal_checksum, "journal_checksum"},
1156         {Opt_nojournal_checksum, "nojournal_checksum"},
1157         {Opt_journal_async_commit, "journal_async_commit"},
1158         {Opt_abort, "abort"},
1159         {Opt_data_journal, "data=journal"},
1160         {Opt_data_ordered, "data=ordered"},
1161         {Opt_data_writeback, "data=writeback"},
1162         {Opt_data_err_abort, "data_err=abort"},
1163         {Opt_data_err_ignore, "data_err=ignore"},
1164         {Opt_offusrjquota, "usrjquota="},
1165         {Opt_usrjquota, "usrjquota=%s"},
1166         {Opt_offgrpjquota, "grpjquota="},
1167         {Opt_grpjquota, "grpjquota=%s"},
1168         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1169         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1170         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1171         {Opt_grpquota, "grpquota"},
1172         {Opt_noquota, "noquota"},
1173         {Opt_quota, "quota"},
1174         {Opt_usrquota, "usrquota"},
1175         {Opt_barrier, "barrier=%u"},
1176         {Opt_barrier, "barrier"},
1177         {Opt_nobarrier, "nobarrier"},
1178         {Opt_i_version, "i_version"},
1179         {Opt_dax, "dax"},
1180         {Opt_stripe, "stripe=%u"},
1181         {Opt_delalloc, "delalloc"},
1182         {Opt_lazytime, "lazytime"},
1183         {Opt_nolazytime, "nolazytime"},
1184         {Opt_nodelalloc, "nodelalloc"},
1185         {Opt_removed, "mblk_io_submit"},
1186         {Opt_removed, "nomblk_io_submit"},
1187         {Opt_block_validity, "block_validity"},
1188         {Opt_noblock_validity, "noblock_validity"},
1189         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1190         {Opt_journal_ioprio, "journal_ioprio=%u"},
1191         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1192         {Opt_auto_da_alloc, "auto_da_alloc"},
1193         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1194         {Opt_dioread_nolock, "dioread_nolock"},
1195         {Opt_dioread_lock, "dioread_lock"},
1196         {Opt_discard, "discard"},
1197         {Opt_nodiscard, "nodiscard"},
1198         {Opt_init_itable, "init_itable=%u"},
1199         {Opt_init_itable, "init_itable"},
1200         {Opt_noinit_itable, "noinit_itable"},
1201         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1202         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1203         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1204         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1205         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1206         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1207         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1208         {Opt_err, NULL},
1209 };
1210
1211 static ext4_fsblk_t get_sb_block(void **data)
1212 {
1213         ext4_fsblk_t    sb_block;
1214         char            *options = (char *) *data;
1215
1216         if (!options || strncmp(options, "sb=", 3) != 0)
1217                 return 1;       /* Default location */
1218
1219         options += 3;
1220         /* TODO: use simple_strtoll with >32bit ext4 */
1221         sb_block = simple_strtoul(options, &options, 0);
1222         if (*options && *options != ',') {
1223                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1224                        (char *) *data);
1225                 return 1;
1226         }
1227         if (*options == ',')
1228                 options++;
1229         *data = (void *) options;
1230
1231         return sb_block;
1232 }
1233
1234 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1235 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1236         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1237
1238 #ifdef CONFIG_QUOTA
1239 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1240 {
1241         struct ext4_sb_info *sbi = EXT4_SB(sb);
1242         char *qname;
1243         int ret = -1;
1244
1245         if (sb_any_quota_loaded(sb) &&
1246                 !sbi->s_qf_names[qtype]) {
1247                 ext4_msg(sb, KERN_ERR,
1248                         "Cannot change journaled "
1249                         "quota options when quota turned on");
1250                 return -1;
1251         }
1252         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1253                 ext4_msg(sb, KERN_ERR, "Cannot set journaled quota options "
1254                          "when QUOTA feature is enabled");
1255                 return -1;
1256         }
1257         qname = match_strdup(args);
1258         if (!qname) {
1259                 ext4_msg(sb, KERN_ERR,
1260                         "Not enough memory for storing quotafile name");
1261                 return -1;
1262         }
1263         if (sbi->s_qf_names[qtype]) {
1264                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1265                         ret = 1;
1266                 else
1267                         ext4_msg(sb, KERN_ERR,
1268                                  "%s quota file already specified",
1269                                  QTYPE2NAME(qtype));
1270                 goto errout;
1271         }
1272         if (strchr(qname, '/')) {
1273                 ext4_msg(sb, KERN_ERR,
1274                         "quotafile must be on filesystem root");
1275                 goto errout;
1276         }
1277         sbi->s_qf_names[qtype] = qname;
1278         set_opt(sb, QUOTA);
1279         return 1;
1280 errout:
1281         kfree(qname);
1282         return ret;
1283 }
1284
1285 static int clear_qf_name(struct super_block *sb, int qtype)
1286 {
1287
1288         struct ext4_sb_info *sbi = EXT4_SB(sb);
1289
1290         if (sb_any_quota_loaded(sb) &&
1291                 sbi->s_qf_names[qtype]) {
1292                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1293                         " when quota turned on");
1294                 return -1;
1295         }
1296         kfree(sbi->s_qf_names[qtype]);
1297         sbi->s_qf_names[qtype] = NULL;
1298         return 1;
1299 }
1300 #endif
1301
1302 #define MOPT_SET        0x0001
1303 #define MOPT_CLEAR      0x0002
1304 #define MOPT_NOSUPPORT  0x0004
1305 #define MOPT_EXPLICIT   0x0008
1306 #define MOPT_CLEAR_ERR  0x0010
1307 #define MOPT_GTE0       0x0020
1308 #ifdef CONFIG_QUOTA
1309 #define MOPT_Q          0
1310 #define MOPT_QFMT       0x0040
1311 #else
1312 #define MOPT_Q          MOPT_NOSUPPORT
1313 #define MOPT_QFMT       MOPT_NOSUPPORT
1314 #endif
1315 #define MOPT_DATAJ      0x0080
1316 #define MOPT_NO_EXT2    0x0100
1317 #define MOPT_NO_EXT3    0x0200
1318 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1319 #define MOPT_STRING     0x0400
1320
1321 static const struct mount_opts {
1322         int     token;
1323         int     mount_opt;
1324         int     flags;
1325 } ext4_mount_opts[] = {
1326         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1327         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1328         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1329         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1330         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1331         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1332         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1333          MOPT_EXT4_ONLY | MOPT_SET},
1334         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1335          MOPT_EXT4_ONLY | MOPT_CLEAR},
1336         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1337         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1338         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1339          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1340         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1341          MOPT_EXT4_ONLY | MOPT_CLEAR},
1342         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1343          MOPT_EXT4_ONLY | MOPT_CLEAR},
1344         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1345          MOPT_EXT4_ONLY | MOPT_SET},
1346         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1347                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1348          MOPT_EXT4_ONLY | MOPT_SET},
1349         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1350         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1351         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1352         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1353         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1354          MOPT_NO_EXT2 | MOPT_SET},
1355         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1356          MOPT_NO_EXT2 | MOPT_CLEAR},
1357         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1358         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1359         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1360         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1361         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1362         {Opt_commit, 0, MOPT_GTE0},
1363         {Opt_max_batch_time, 0, MOPT_GTE0},
1364         {Opt_min_batch_time, 0, MOPT_GTE0},
1365         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1366         {Opt_init_itable, 0, MOPT_GTE0},
1367         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1368         {Opt_stripe, 0, MOPT_GTE0},
1369         {Opt_resuid, 0, MOPT_GTE0},
1370         {Opt_resgid, 0, MOPT_GTE0},
1371         {Opt_journal_dev, 0, MOPT_GTE0},
1372         {Opt_journal_path, 0, MOPT_STRING},
1373         {Opt_journal_ioprio, 0, MOPT_GTE0},
1374         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1375         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1376         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1377          MOPT_NO_EXT2 | MOPT_DATAJ},
1378         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1379         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1380 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1381         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1382         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1383 #else
1384         {Opt_acl, 0, MOPT_NOSUPPORT},
1385         {Opt_noacl, 0, MOPT_NOSUPPORT},
1386 #endif
1387         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1388         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1389         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1390         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1391                                                         MOPT_SET | MOPT_Q},
1392         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1393                                                         MOPT_SET | MOPT_Q},
1394         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1395                        EXT4_MOUNT_GRPQUOTA), MOPT_CLEAR | MOPT_Q},
1396         {Opt_usrjquota, 0, MOPT_Q},
1397         {Opt_grpjquota, 0, MOPT_Q},
1398         {Opt_offusrjquota, 0, MOPT_Q},
1399         {Opt_offgrpjquota, 0, MOPT_Q},
1400         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1401         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1402         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1403         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1404         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1405         {Opt_err, 0, 0}
1406 };
1407
1408 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1409                             substring_t *args, unsigned long *journal_devnum,
1410                             unsigned int *journal_ioprio, int is_remount)
1411 {
1412         struct ext4_sb_info *sbi = EXT4_SB(sb);
1413         const struct mount_opts *m;
1414         kuid_t uid;
1415         kgid_t gid;
1416         int arg = 0;
1417
1418 #ifdef CONFIG_QUOTA
1419         if (token == Opt_usrjquota)
1420                 return set_qf_name(sb, USRQUOTA, &args[0]);
1421         else if (token == Opt_grpjquota)
1422                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1423         else if (token == Opt_offusrjquota)
1424                 return clear_qf_name(sb, USRQUOTA);
1425         else if (token == Opt_offgrpjquota)
1426                 return clear_qf_name(sb, GRPQUOTA);
1427 #endif
1428         switch (token) {
1429         case Opt_noacl:
1430         case Opt_nouser_xattr:
1431                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1432                 break;
1433         case Opt_sb:
1434                 return 1;       /* handled by get_sb_block() */
1435         case Opt_removed:
1436                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1437                 return 1;
1438         case Opt_abort:
1439                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1440                 return 1;
1441         case Opt_i_version:
1442                 sb->s_flags |= MS_I_VERSION;
1443                 return 1;
1444         case Opt_lazytime:
1445                 sb->s_flags |= MS_LAZYTIME;
1446                 return 1;
1447         case Opt_nolazytime:
1448                 sb->s_flags &= ~MS_LAZYTIME;
1449                 return 1;
1450         }
1451
1452         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1453                 if (token == m->token)
1454                         break;
1455
1456         if (m->token == Opt_err) {
1457                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1458                          "or missing value", opt);
1459                 return -1;
1460         }
1461
1462         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1463                 ext4_msg(sb, KERN_ERR,
1464                          "Mount option \"%s\" incompatible with ext2", opt);
1465                 return -1;
1466         }
1467         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1468                 ext4_msg(sb, KERN_ERR,
1469                          "Mount option \"%s\" incompatible with ext3", opt);
1470                 return -1;
1471         }
1472
1473         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1474                 return -1;
1475         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1476                 return -1;
1477         if (m->flags & MOPT_EXPLICIT)
1478                 set_opt2(sb, EXPLICIT_DELALLOC);
1479         if (m->flags & MOPT_CLEAR_ERR)
1480                 clear_opt(sb, ERRORS_MASK);
1481         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1482                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1483                          "options when quota turned on");
1484                 return -1;
1485         }
1486
1487         if (m->flags & MOPT_NOSUPPORT) {
1488                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1489         } else if (token == Opt_commit) {
1490                 if (arg == 0)
1491                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1492                 sbi->s_commit_interval = HZ * arg;
1493         } else if (token == Opt_max_batch_time) {
1494                 sbi->s_max_batch_time = arg;
1495         } else if (token == Opt_min_batch_time) {
1496                 sbi->s_min_batch_time = arg;
1497         } else if (token == Opt_inode_readahead_blks) {
1498                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1499                         ext4_msg(sb, KERN_ERR,
1500                                  "EXT4-fs: inode_readahead_blks must be "
1501                                  "0 or a power of 2 smaller than 2^31");
1502                         return -1;
1503                 }
1504                 sbi->s_inode_readahead_blks = arg;
1505         } else if (token == Opt_init_itable) {
1506                 set_opt(sb, INIT_INODE_TABLE);
1507                 if (!args->from)
1508                         arg = EXT4_DEF_LI_WAIT_MULT;
1509                 sbi->s_li_wait_mult = arg;
1510         } else if (token == Opt_max_dir_size_kb) {
1511                 sbi->s_max_dir_size_kb = arg;
1512         } else if (token == Opt_stripe) {
1513                 sbi->s_stripe = arg;
1514         } else if (token == Opt_resuid) {
1515                 uid = make_kuid(current_user_ns(), arg);
1516                 if (!uid_valid(uid)) {
1517                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1518                         return -1;
1519                 }
1520                 sbi->s_resuid = uid;
1521         } else if (token == Opt_resgid) {
1522                 gid = make_kgid(current_user_ns(), arg);
1523                 if (!gid_valid(gid)) {
1524                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1525                         return -1;
1526                 }
1527                 sbi->s_resgid = gid;
1528         } else if (token == Opt_journal_dev) {
1529                 if (is_remount) {
1530                         ext4_msg(sb, KERN_ERR,
1531                                  "Cannot specify journal on remount");
1532                         return -1;
1533                 }
1534                 *journal_devnum = arg;
1535         } else if (token == Opt_journal_path) {
1536                 char *journal_path;
1537                 struct inode *journal_inode;
1538                 struct path path;
1539                 int error;
1540
1541                 if (is_remount) {
1542                         ext4_msg(sb, KERN_ERR,
1543                                  "Cannot specify journal on remount");
1544                         return -1;
1545                 }
1546                 journal_path = match_strdup(&args[0]);
1547                 if (!journal_path) {
1548                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1549                                 "journal device string");
1550                         return -1;
1551                 }
1552
1553                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1554                 if (error) {
1555                         ext4_msg(sb, KERN_ERR, "error: could not find "
1556                                 "journal device path: error %d", error);
1557                         kfree(journal_path);
1558                         return -1;
1559                 }
1560
1561                 journal_inode = d_inode(path.dentry);
1562                 if (!S_ISBLK(journal_inode->i_mode)) {
1563                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1564                                 "is not a block device", journal_path);
1565                         path_put(&path);
1566                         kfree(journal_path);
1567                         return -1;
1568                 }
1569
1570                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1571                 path_put(&path);
1572                 kfree(journal_path);
1573         } else if (token == Opt_journal_ioprio) {
1574                 if (arg > 7) {
1575                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1576                                  " (must be 0-7)");
1577                         return -1;
1578                 }
1579                 *journal_ioprio =
1580                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1581         } else if (token == Opt_test_dummy_encryption) {
1582 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1583                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1584                 ext4_msg(sb, KERN_WARNING,
1585                          "Test dummy encryption mode enabled");
1586 #else
1587                 ext4_msg(sb, KERN_WARNING,
1588                          "Test dummy encryption mount option ignored");
1589 #endif
1590         } else if (m->flags & MOPT_DATAJ) {
1591                 if (is_remount) {
1592                         if (!sbi->s_journal)
1593                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1594                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1595                                 ext4_msg(sb, KERN_ERR,
1596                                          "Cannot change data mode on remount");
1597                                 return -1;
1598                         }
1599                 } else {
1600                         clear_opt(sb, DATA_FLAGS);
1601                         sbi->s_mount_opt |= m->mount_opt;
1602                 }
1603 #ifdef CONFIG_QUOTA
1604         } else if (m->flags & MOPT_QFMT) {
1605                 if (sb_any_quota_loaded(sb) &&
1606                     sbi->s_jquota_fmt != m->mount_opt) {
1607                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1608                                  "quota options when quota turned on");
1609                         return -1;
1610                 }
1611                 if (EXT4_HAS_RO_COMPAT_FEATURE(sb,
1612                                                EXT4_FEATURE_RO_COMPAT_QUOTA)) {
1613                         ext4_msg(sb, KERN_ERR,
1614                                  "Cannot set journaled quota options "
1615                                  "when QUOTA feature is enabled");
1616                         return -1;
1617                 }
1618                 sbi->s_jquota_fmt = m->mount_opt;
1619 #endif
1620 #ifndef CONFIG_FS_DAX
1621         } else if (token == Opt_dax) {
1622                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1623                 return -1;
1624 #endif
1625         } else {
1626                 if (!args->from)
1627                         arg = 1;
1628                 if (m->flags & MOPT_CLEAR)
1629                         arg = !arg;
1630                 else if (unlikely(!(m->flags & MOPT_SET))) {
1631                         ext4_msg(sb, KERN_WARNING,
1632                                  "buggy handling of option %s", opt);
1633                         WARN_ON(1);
1634                         return -1;
1635                 }
1636                 if (arg != 0)
1637                         sbi->s_mount_opt |= m->mount_opt;
1638                 else
1639                         sbi->s_mount_opt &= ~m->mount_opt;
1640         }
1641         return 1;
1642 }
1643
1644 static int parse_options(char *options, struct super_block *sb,
1645                          unsigned long *journal_devnum,
1646                          unsigned int *journal_ioprio,
1647                          int is_remount)
1648 {
1649         struct ext4_sb_info *sbi = EXT4_SB(sb);
1650         char *p;
1651         substring_t args[MAX_OPT_ARGS];
1652         int token;
1653
1654         if (!options)
1655                 return 1;
1656
1657         while ((p = strsep(&options, ",")) != NULL) {
1658                 if (!*p)
1659                         continue;
1660                 /*
1661                  * Initialize args struct so we know whether arg was
1662                  * found; some options take optional arguments.
1663                  */
1664                 args[0].to = args[0].from = NULL;
1665                 token = match_token(p, tokens, args);
1666                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1667                                      journal_ioprio, is_remount) < 0)
1668                         return 0;
1669         }
1670 #ifdef CONFIG_QUOTA
1671         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
1672             (test_opt(sb, USRQUOTA) || test_opt(sb, GRPQUOTA))) {
1673                 ext4_msg(sb, KERN_ERR, "Cannot set quota options when QUOTA "
1674                          "feature is enabled");
1675                 return 0;
1676         }
1677         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1678                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1679                         clear_opt(sb, USRQUOTA);
1680
1681                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1682                         clear_opt(sb, GRPQUOTA);
1683
1684                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1685                         ext4_msg(sb, KERN_ERR, "old and new quota "
1686                                         "format mixing");
1687                         return 0;
1688                 }
1689
1690                 if (!sbi->s_jquota_fmt) {
1691                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1692                                         "not specified");
1693                         return 0;
1694                 }
1695         }
1696 #endif
1697         if (test_opt(sb, DIOREAD_NOLOCK)) {
1698                 int blocksize =
1699                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1700
1701                 if (blocksize < PAGE_CACHE_SIZE) {
1702                         ext4_msg(sb, KERN_ERR, "can't mount with "
1703                                  "dioread_nolock if block size != PAGE_SIZE");
1704                         return 0;
1705                 }
1706         }
1707         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
1708             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
1709                 ext4_msg(sb, KERN_ERR, "can't mount with journal_async_commit "
1710                          "in data=ordered mode");
1711                 return 0;
1712         }
1713         return 1;
1714 }
1715
1716 static inline void ext4_show_quota_options(struct seq_file *seq,
1717                                            struct super_block *sb)
1718 {
1719 #if defined(CONFIG_QUOTA)
1720         struct ext4_sb_info *sbi = EXT4_SB(sb);
1721
1722         if (sbi->s_jquota_fmt) {
1723                 char *fmtname = "";
1724
1725                 switch (sbi->s_jquota_fmt) {
1726                 case QFMT_VFS_OLD:
1727                         fmtname = "vfsold";
1728                         break;
1729                 case QFMT_VFS_V0:
1730                         fmtname = "vfsv0";
1731                         break;
1732                 case QFMT_VFS_V1:
1733                         fmtname = "vfsv1";
1734                         break;
1735                 }
1736                 seq_printf(seq, ",jqfmt=%s", fmtname);
1737         }
1738
1739         if (sbi->s_qf_names[USRQUOTA])
1740                 seq_printf(seq, ",usrjquota=%s", sbi->s_qf_names[USRQUOTA]);
1741
1742         if (sbi->s_qf_names[GRPQUOTA])
1743                 seq_printf(seq, ",grpjquota=%s", sbi->s_qf_names[GRPQUOTA]);
1744 #endif
1745 }
1746
1747 static const char *token2str(int token)
1748 {
1749         const struct match_token *t;
1750
1751         for (t = tokens; t->token != Opt_err; t++)
1752                 if (t->token == token && !strchr(t->pattern, '='))
1753                         break;
1754         return t->pattern;
1755 }
1756
1757 /*
1758  * Show an option if
1759  *  - it's set to a non-default value OR
1760  *  - if the per-sb default is different from the global default
1761  */
1762 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1763                               int nodefs)
1764 {
1765         struct ext4_sb_info *sbi = EXT4_SB(sb);
1766         struct ext4_super_block *es = sbi->s_es;
1767         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1768         const struct mount_opts *m;
1769         char sep = nodefs ? '\n' : ',';
1770
1771 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1772 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1773
1774         if (sbi->s_sb_block != 1)
1775                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1776
1777         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1778                 int want_set = m->flags & MOPT_SET;
1779                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1780                     (m->flags & MOPT_CLEAR_ERR))
1781                         continue;
1782                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1783                         continue; /* skip if same as the default */
1784                 if ((want_set &&
1785                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1786                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1787                         continue; /* select Opt_noFoo vs Opt_Foo */
1788                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1789         }
1790
1791         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1792             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1793                 SEQ_OPTS_PRINT("resuid=%u",
1794                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1795         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1796             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1797                 SEQ_OPTS_PRINT("resgid=%u",
1798                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1799         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1800         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1801                 SEQ_OPTS_PUTS("errors=remount-ro");
1802         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1803                 SEQ_OPTS_PUTS("errors=continue");
1804         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
1805                 SEQ_OPTS_PUTS("errors=panic");
1806         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
1807                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
1808         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
1809                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
1810         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
1811                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
1812         if (sb->s_flags & MS_I_VERSION)
1813                 SEQ_OPTS_PUTS("i_version");
1814         if (nodefs || sbi->s_stripe)
1815                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
1816         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
1817                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
1818                         SEQ_OPTS_PUTS("data=journal");
1819                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
1820                         SEQ_OPTS_PUTS("data=ordered");
1821                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
1822                         SEQ_OPTS_PUTS("data=writeback");
1823         }
1824         if (nodefs ||
1825             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
1826                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
1827                                sbi->s_inode_readahead_blks);
1828
1829         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
1830                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
1831                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
1832         if (nodefs || sbi->s_max_dir_size_kb)
1833                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
1834
1835         ext4_show_quota_options(seq, sb);
1836         return 0;
1837 }
1838
1839 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
1840 {
1841         return _ext4_show_options(seq, root->d_sb, 0);
1842 }
1843
1844 static int options_seq_show(struct seq_file *seq, void *offset)
1845 {
1846         struct super_block *sb = seq->private;
1847         int rc;
1848
1849         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
1850         rc = _ext4_show_options(seq, sb, 1);
1851         seq_puts(seq, "\n");
1852         return rc;
1853 }
1854
1855 static int options_open_fs(struct inode *inode, struct file *file)
1856 {
1857         return single_open(file, options_seq_show, PDE_DATA(inode));
1858 }
1859
1860 static const struct file_operations ext4_seq_options_fops = {
1861         .owner = THIS_MODULE,
1862         .open = options_open_fs,
1863         .read = seq_read,
1864         .llseek = seq_lseek,
1865         .release = single_release,
1866 };
1867
1868 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
1869                             int read_only)
1870 {
1871         struct ext4_sb_info *sbi = EXT4_SB(sb);
1872         int res = 0;
1873
1874         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
1875                 ext4_msg(sb, KERN_ERR, "revision level too high, "
1876                          "forcing read-only mode");
1877                 res = MS_RDONLY;
1878         }
1879         if (read_only)
1880                 goto done;
1881         if (!(sbi->s_mount_state & EXT4_VALID_FS))
1882                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
1883                          "running e2fsck is recommended");
1884         else if (sbi->s_mount_state & EXT4_ERROR_FS)
1885                 ext4_msg(sb, KERN_WARNING,
1886                          "warning: mounting fs with errors, "
1887                          "running e2fsck is recommended");
1888         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
1889                  le16_to_cpu(es->s_mnt_count) >=
1890                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
1891                 ext4_msg(sb, KERN_WARNING,
1892                          "warning: maximal mount count reached, "
1893                          "running e2fsck is recommended");
1894         else if (le32_to_cpu(es->s_checkinterval) &&
1895                 (le32_to_cpu(es->s_lastcheck) +
1896                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
1897                 ext4_msg(sb, KERN_WARNING,
1898                          "warning: checktime reached, "
1899                          "running e2fsck is recommended");
1900         if (!sbi->s_journal)
1901                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
1902         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
1903                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
1904         le16_add_cpu(&es->s_mnt_count, 1);
1905         es->s_mtime = cpu_to_le32(get_seconds());
1906         ext4_update_dynamic_rev(sb);
1907         if (sbi->s_journal)
1908                 EXT4_SET_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER);
1909
1910         ext4_commit_super(sb, 1);
1911 done:
1912         if (test_opt(sb, DEBUG))
1913                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
1914                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
1915                         sb->s_blocksize,
1916                         sbi->s_groups_count,
1917                         EXT4_BLOCKS_PER_GROUP(sb),
1918                         EXT4_INODES_PER_GROUP(sb),
1919                         sbi->s_mount_opt, sbi->s_mount_opt2);
1920
1921         cleancache_init_fs(sb);
1922         return res;
1923 }
1924
1925 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
1926 {
1927         struct ext4_sb_info *sbi = EXT4_SB(sb);
1928         struct flex_groups *new_groups;
1929         int size;
1930
1931         if (!sbi->s_log_groups_per_flex)
1932                 return 0;
1933
1934         size = ext4_flex_group(sbi, ngroup - 1) + 1;
1935         if (size <= sbi->s_flex_groups_allocated)
1936                 return 0;
1937
1938         size = roundup_pow_of_two(size * sizeof(struct flex_groups));
1939         new_groups = ext4_kvzalloc(size, GFP_KERNEL);
1940         if (!new_groups) {
1941                 ext4_msg(sb, KERN_ERR, "not enough memory for %d flex groups",
1942                          size / (int) sizeof(struct flex_groups));
1943                 return -ENOMEM;
1944         }
1945
1946         if (sbi->s_flex_groups) {
1947                 memcpy(new_groups, sbi->s_flex_groups,
1948                        (sbi->s_flex_groups_allocated *
1949                         sizeof(struct flex_groups)));
1950                 kvfree(sbi->s_flex_groups);
1951         }
1952         sbi->s_flex_groups = new_groups;
1953         sbi->s_flex_groups_allocated = size / sizeof(struct flex_groups);
1954         return 0;
1955 }
1956
1957 static int ext4_fill_flex_info(struct super_block *sb)
1958 {
1959         struct ext4_sb_info *sbi = EXT4_SB(sb);
1960         struct ext4_group_desc *gdp = NULL;
1961         ext4_group_t flex_group;
1962         int i, err;
1963
1964         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
1965         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
1966                 sbi->s_log_groups_per_flex = 0;
1967                 return 1;
1968         }
1969
1970         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
1971         if (err)
1972                 goto failed;
1973
1974         for (i = 0; i < sbi->s_groups_count; i++) {
1975                 gdp = ext4_get_group_desc(sb, i, NULL);
1976
1977                 flex_group = ext4_flex_group(sbi, i);
1978                 atomic_add(ext4_free_inodes_count(sb, gdp),
1979                            &sbi->s_flex_groups[flex_group].free_inodes);
1980                 atomic64_add(ext4_free_group_clusters(sb, gdp),
1981                              &sbi->s_flex_groups[flex_group].free_clusters);
1982                 atomic_add(ext4_used_dirs_count(sb, gdp),
1983                            &sbi->s_flex_groups[flex_group].used_dirs);
1984         }
1985
1986         return 1;
1987 failed:
1988         return 0;
1989 }
1990
1991 static __le16 ext4_group_desc_csum(struct ext4_sb_info *sbi, __u32 block_group,
1992                                    struct ext4_group_desc *gdp)
1993 {
1994         int offset;
1995         __u16 crc = 0;
1996         __le32 le_group = cpu_to_le32(block_group);
1997
1998         if (ext4_has_metadata_csum(sbi->s_sb)) {
1999                 /* Use new metadata_csum algorithm */
2000                 __le16 save_csum;
2001                 __u32 csum32;
2002
2003                 save_csum = gdp->bg_checksum;
2004                 gdp->bg_checksum = 0;
2005                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2006                                      sizeof(le_group));
2007                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp,
2008                                      sbi->s_desc_size);
2009                 gdp->bg_checksum = save_csum;
2010
2011                 crc = csum32 & 0xFFFF;
2012                 goto out;
2013         }
2014
2015         /* old crc16 code */
2016         if (!(sbi->s_es->s_feature_ro_compat &
2017               cpu_to_le32(EXT4_FEATURE_RO_COMPAT_GDT_CSUM)))
2018                 return 0;
2019
2020         offset = offsetof(struct ext4_group_desc, bg_checksum);
2021
2022         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2023         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2024         crc = crc16(crc, (__u8 *)gdp, offset);
2025         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2026         /* for checksum of struct ext4_group_desc do the rest...*/
2027         if ((sbi->s_es->s_feature_incompat &
2028              cpu_to_le32(EXT4_FEATURE_INCOMPAT_64BIT)) &&
2029             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2030                 crc = crc16(crc, (__u8 *)gdp + offset,
2031                             le16_to_cpu(sbi->s_es->s_desc_size) -
2032                                 offset);
2033
2034 out:
2035         return cpu_to_le16(crc);
2036 }
2037
2038 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2039                                 struct ext4_group_desc *gdp)
2040 {
2041         if (ext4_has_group_desc_csum(sb) &&
2042             (gdp->bg_checksum != ext4_group_desc_csum(EXT4_SB(sb),
2043                                                       block_group, gdp)))
2044                 return 0;
2045
2046         return 1;
2047 }
2048
2049 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2050                               struct ext4_group_desc *gdp)
2051 {
2052         if (!ext4_has_group_desc_csum(sb))
2053                 return;
2054         gdp->bg_checksum = ext4_group_desc_csum(EXT4_SB(sb), block_group, gdp);
2055 }
2056
2057 /* Called at mount-time, super-block is locked */
2058 static int ext4_check_descriptors(struct super_block *sb,
2059                                   ext4_group_t *first_not_zeroed)
2060 {
2061         struct ext4_sb_info *sbi = EXT4_SB(sb);
2062         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2063         ext4_fsblk_t last_block;
2064         ext4_fsblk_t block_bitmap;
2065         ext4_fsblk_t inode_bitmap;
2066         ext4_fsblk_t inode_table;
2067         int flexbg_flag = 0;
2068         ext4_group_t i, grp = sbi->s_groups_count;
2069
2070         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_FLEX_BG))
2071                 flexbg_flag = 1;
2072
2073         ext4_debug("Checking group descriptors");
2074
2075         for (i = 0; i < sbi->s_groups_count; i++) {
2076                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2077
2078                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2079                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2080                 else
2081                         last_block = first_block +
2082                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2083
2084                 if ((grp == sbi->s_groups_count) &&
2085                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2086                         grp = i;
2087
2088                 block_bitmap = ext4_block_bitmap(sb, gdp);
2089                 if (block_bitmap < first_block || block_bitmap > last_block) {
2090                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2091                                "Block bitmap for group %u not in group "
2092                                "(block %llu)!", i, block_bitmap);
2093                         return 0;
2094                 }
2095                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2096                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2097                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2098                                "Inode bitmap for group %u not in group "
2099                                "(block %llu)!", i, inode_bitmap);
2100                         return 0;
2101                 }
2102                 inode_table = ext4_inode_table(sb, gdp);
2103                 if (inode_table < first_block ||
2104                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2105                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2106                                "Inode table for group %u not in group "
2107                                "(block %llu)!", i, inode_table);
2108                         return 0;
2109                 }
2110                 ext4_lock_group(sb, i);
2111                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2112                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2113                                  "Checksum for group %u failed (%u!=%u)",
2114                                  i, le16_to_cpu(ext4_group_desc_csum(sbi, i,
2115                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2116                         if (!(sb->s_flags & MS_RDONLY)) {
2117                                 ext4_unlock_group(sb, i);
2118                                 return 0;
2119                         }
2120                 }
2121                 ext4_unlock_group(sb, i);
2122                 if (!flexbg_flag)
2123                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2124         }
2125         if (NULL != first_not_zeroed)
2126                 *first_not_zeroed = grp;
2127         return 1;
2128 }
2129
2130 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2131  * the superblock) which were deleted from all directories, but held open by
2132  * a process at the time of a crash.  We walk the list and try to delete these
2133  * inodes at recovery time (only with a read-write filesystem).
2134  *
2135  * In order to keep the orphan inode chain consistent during traversal (in
2136  * case of crash during recovery), we link each inode into the superblock
2137  * orphan list_head and handle it the same way as an inode deletion during
2138  * normal operation (which journals the operations for us).
2139  *
2140  * We only do an iget() and an iput() on each inode, which is very safe if we
2141  * accidentally point at an in-use or already deleted inode.  The worst that
2142  * can happen in this case is that we get a "bit already cleared" message from
2143  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2144  * e2fsck was run on this filesystem, and it must have already done the orphan
2145  * inode cleanup for us, so we can safely abort without any further action.
2146  */
2147 static void ext4_orphan_cleanup(struct super_block *sb,
2148                                 struct ext4_super_block *es)
2149 {
2150         unsigned int s_flags = sb->s_flags;
2151         int nr_orphans = 0, nr_truncates = 0;
2152 #ifdef CONFIG_QUOTA
2153         int i;
2154 #endif
2155         if (!es->s_last_orphan) {
2156                 jbd_debug(4, "no orphan inodes to clean up\n");
2157                 return;
2158         }
2159
2160         if (bdev_read_only(sb->s_bdev)) {
2161                 ext4_msg(sb, KERN_ERR, "write access "
2162                         "unavailable, skipping orphan cleanup");
2163                 return;
2164         }
2165
2166         /* Check if feature set would not allow a r/w mount */
2167         if (!ext4_feature_set_ok(sb, 0)) {
2168                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2169                          "unknown ROCOMPAT features");
2170                 return;
2171         }
2172
2173         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2174                 /* don't clear list on RO mount w/ errors */
2175                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2176                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2177                                   "clearing orphan list.\n");
2178                         es->s_last_orphan = 0;
2179                 }
2180                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2181                 return;
2182         }
2183
2184         if (s_flags & MS_RDONLY) {
2185                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2186                 sb->s_flags &= ~MS_RDONLY;
2187         }
2188 #ifdef CONFIG_QUOTA
2189         /* Needed for iput() to work correctly and not trash data */
2190         sb->s_flags |= MS_ACTIVE;
2191         /* Turn on quotas so that they are updated correctly */
2192         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2193                 if (EXT4_SB(sb)->s_qf_names[i]) {
2194                         int ret = ext4_quota_on_mount(sb, i);
2195                         if (ret < 0)
2196                                 ext4_msg(sb, KERN_ERR,
2197                                         "Cannot turn on journaled "
2198                                         "quota: error %d", ret);
2199                 }
2200         }
2201 #endif
2202
2203         while (es->s_last_orphan) {
2204                 struct inode *inode;
2205
2206                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2207                 if (IS_ERR(inode)) {
2208                         es->s_last_orphan = 0;
2209                         break;
2210                 }
2211
2212                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2213                 dquot_initialize(inode);
2214                 if (inode->i_nlink) {
2215                         if (test_opt(sb, DEBUG))
2216                                 ext4_msg(sb, KERN_DEBUG,
2217                                         "%s: truncating inode %lu to %lld bytes",
2218                                         __func__, inode->i_ino, inode->i_size);
2219                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2220                                   inode->i_ino, inode->i_size);
2221                         mutex_lock(&inode->i_mutex);
2222                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2223                         ext4_truncate(inode);
2224                         mutex_unlock(&inode->i_mutex);
2225                         nr_truncates++;
2226                 } else {
2227                         if (test_opt(sb, DEBUG))
2228                                 ext4_msg(sb, KERN_DEBUG,
2229                                         "%s: deleting unreferenced inode %lu",
2230                                         __func__, inode->i_ino);
2231                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2232                                   inode->i_ino);
2233                         nr_orphans++;
2234                 }
2235                 iput(inode);  /* The delete magic happens here! */
2236         }
2237
2238 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2239
2240         if (nr_orphans)
2241                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2242                        PLURAL(nr_orphans));
2243         if (nr_truncates)
2244                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2245                        PLURAL(nr_truncates));
2246 #ifdef CONFIG_QUOTA
2247         /* Turn quotas off */
2248         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2249                 if (sb_dqopt(sb)->files[i])
2250                         dquot_quota_off(sb, i);
2251         }
2252 #endif
2253         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2254 }
2255
2256 /*
2257  * Maximal extent format file size.
2258  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2259  * extent format containers, within a sector_t, and within i_blocks
2260  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2261  * so that won't be a limiting factor.
2262  *
2263  * However there is other limiting factor. We do store extents in the form
2264  * of starting block and length, hence the resulting length of the extent
2265  * covering maximum file size must fit into on-disk format containers as
2266  * well. Given that length is always by 1 unit bigger than max unit (because
2267  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2268  *
2269  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2270  */
2271 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2272 {
2273         loff_t res;
2274         loff_t upper_limit = MAX_LFS_FILESIZE;
2275
2276         /* small i_blocks in vfs inode? */
2277         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2278                 /*
2279                  * CONFIG_LBDAF is not enabled implies the inode
2280                  * i_block represent total blocks in 512 bytes
2281                  * 32 == size of vfs inode i_blocks * 8
2282                  */
2283                 upper_limit = (1LL << 32) - 1;
2284
2285                 /* total blocks in file system block size */
2286                 upper_limit >>= (blkbits - 9);
2287                 upper_limit <<= blkbits;
2288         }
2289
2290         /*
2291          * 32-bit extent-start container, ee_block. We lower the maxbytes
2292          * by one fs block, so ee_len can cover the extent of maximum file
2293          * size
2294          */
2295         res = (1LL << 32) - 1;
2296         res <<= blkbits;
2297
2298         /* Sanity check against vm- & vfs- imposed limits */
2299         if (res > upper_limit)
2300                 res = upper_limit;
2301
2302         return res;
2303 }
2304
2305 /*
2306  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2307  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2308  * We need to be 1 filesystem block less than the 2^48 sector limit.
2309  */
2310 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2311 {
2312         loff_t res = EXT4_NDIR_BLOCKS;
2313         int meta_blocks;
2314         loff_t upper_limit;
2315         /* This is calculated to be the largest file size for a dense, block
2316          * mapped file such that the file's total number of 512-byte sectors,
2317          * including data and all indirect blocks, does not exceed (2^48 - 1).
2318          *
2319          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2320          * number of 512-byte sectors of the file.
2321          */
2322
2323         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2324                 /*
2325                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2326                  * the inode i_block field represents total file blocks in
2327                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2328                  */
2329                 upper_limit = (1LL << 32) - 1;
2330
2331                 /* total blocks in file system block size */
2332                 upper_limit >>= (bits - 9);
2333
2334         } else {
2335                 /*
2336                  * We use 48 bit ext4_inode i_blocks
2337                  * With EXT4_HUGE_FILE_FL set the i_blocks
2338                  * represent total number of blocks in
2339                  * file system block size
2340                  */
2341                 upper_limit = (1LL << 48) - 1;
2342
2343         }
2344
2345         /* indirect blocks */
2346         meta_blocks = 1;
2347         /* double indirect blocks */
2348         meta_blocks += 1 + (1LL << (bits-2));
2349         /* tripple indirect blocks */
2350         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2351
2352         upper_limit -= meta_blocks;
2353         upper_limit <<= bits;
2354
2355         res += 1LL << (bits-2);
2356         res += 1LL << (2*(bits-2));
2357         res += 1LL << (3*(bits-2));
2358         res <<= bits;
2359         if (res > upper_limit)
2360                 res = upper_limit;
2361
2362         if (res > MAX_LFS_FILESIZE)
2363                 res = MAX_LFS_FILESIZE;
2364
2365         return res;
2366 }
2367
2368 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2369                                    ext4_fsblk_t logical_sb_block, int nr)
2370 {
2371         struct ext4_sb_info *sbi = EXT4_SB(sb);
2372         ext4_group_t bg, first_meta_bg;
2373         int has_super = 0;
2374
2375         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2376
2377         if (!EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_META_BG) ||
2378             nr < first_meta_bg)
2379                 return logical_sb_block + nr + 1;
2380         bg = sbi->s_desc_per_block * nr;
2381         if (ext4_bg_has_super(sb, bg))
2382                 has_super = 1;
2383
2384         /*
2385          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2386          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2387          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2388          * compensate.
2389          */
2390         if (sb->s_blocksize == 1024 && nr == 0 &&
2391             le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) == 0)
2392                 has_super++;
2393
2394         return (has_super + ext4_group_first_block_no(sb, bg));
2395 }
2396
2397 /**
2398  * ext4_get_stripe_size: Get the stripe size.
2399  * @sbi: In memory super block info
2400  *
2401  * If we have specified it via mount option, then
2402  * use the mount option value. If the value specified at mount time is
2403  * greater than the blocks per group use the super block value.
2404  * If the super block value is greater than blocks per group return 0.
2405  * Allocator needs it be less than blocks per group.
2406  *
2407  */
2408 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2409 {
2410         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2411         unsigned long stripe_width =
2412                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2413         int ret;
2414
2415         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2416                 ret = sbi->s_stripe;
2417         else if (stripe_width <= sbi->s_blocks_per_group)
2418                 ret = stripe_width;
2419         else if (stride <= sbi->s_blocks_per_group)
2420                 ret = stride;
2421         else
2422                 ret = 0;
2423
2424         /*
2425          * If the stripe width is 1, this makes no sense and
2426          * we set it to 0 to turn off stripe handling code.
2427          */
2428         if (ret <= 1)
2429                 ret = 0;
2430
2431         return ret;
2432 }
2433
2434 /* sysfs supprt */
2435
2436 struct ext4_attr {
2437         struct attribute attr;
2438         ssize_t (*show)(struct ext4_attr *, struct ext4_sb_info *, char *);
2439         ssize_t (*store)(struct ext4_attr *, struct ext4_sb_info *,
2440                          const char *, size_t);
2441         union {
2442                 int offset;
2443                 int deprecated_val;
2444         } u;
2445 };
2446
2447 static int parse_strtoull(const char *buf,
2448                 unsigned long long max, unsigned long long *value)
2449 {
2450         int ret;
2451
2452         ret = kstrtoull(skip_spaces(buf), 0, value);
2453         if (!ret && *value > max)
2454                 ret = -EINVAL;
2455         return ret;
2456 }
2457
2458 static ssize_t delayed_allocation_blocks_show(struct ext4_attr *a,
2459                                               struct ext4_sb_info *sbi,
2460                                               char *buf)
2461 {
2462         return snprintf(buf, PAGE_SIZE, "%llu\n",
2463                 (s64) EXT4_C2B(sbi,
2464                         percpu_counter_sum(&sbi->s_dirtyclusters_counter)));
2465 }
2466
2467 static ssize_t session_write_kbytes_show(struct ext4_attr *a,
2468                                          struct ext4_sb_info *sbi, char *buf)
2469 {
2470         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2471
2472         if (!sb->s_bdev->bd_part)
2473                 return snprintf(buf, PAGE_SIZE, "0\n");
2474         return snprintf(buf, PAGE_SIZE, "%lu\n",
2475                         (part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2476                          sbi->s_sectors_written_start) >> 1);
2477 }
2478
2479 static ssize_t lifetime_write_kbytes_show(struct ext4_attr *a,
2480                                           struct ext4_sb_info *sbi, char *buf)
2481 {
2482         struct super_block *sb = sbi->s_buddy_cache->i_sb;
2483
2484         if (!sb->s_bdev->bd_part)
2485                 return snprintf(buf, PAGE_SIZE, "0\n");
2486         return snprintf(buf, PAGE_SIZE, "%llu\n",
2487                         (unsigned long long)(sbi->s_kbytes_written +
2488                         ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
2489                           EXT4_SB(sb)->s_sectors_written_start) >> 1)));
2490 }
2491
2492 static ssize_t inode_readahead_blks_store(struct ext4_attr *a,
2493                                           struct ext4_sb_info *sbi,
2494                                           const char *buf, size_t count)
2495 {
2496         unsigned long t;
2497         int ret;
2498
2499         ret = kstrtoul(skip_spaces(buf), 0, &t);
2500         if (ret)
2501                 return ret;
2502
2503         if (t && (!is_power_of_2(t) || t > 0x40000000))
2504                 return -EINVAL;
2505
2506         sbi->s_inode_readahead_blks = t;
2507         return count;
2508 }
2509
2510 static ssize_t sbi_ui_show(struct ext4_attr *a,
2511                            struct ext4_sb_info *sbi, char *buf)
2512 {
2513         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
2514
2515         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2516 }
2517
2518 static ssize_t sbi_ui_store(struct ext4_attr *a,
2519                             struct ext4_sb_info *sbi,
2520                             const char *buf, size_t count)
2521 {
2522         unsigned int *ui = (unsigned int *) (((char *) sbi) + a->u.offset);
2523         unsigned long t;
2524         int ret;
2525
2526         ret = kstrtoul(skip_spaces(buf), 0, &t);
2527         if (ret)
2528                 return ret;
2529         *ui = t;
2530         return count;
2531 }
2532
2533 static ssize_t es_ui_show(struct ext4_attr *a,
2534                            struct ext4_sb_info *sbi, char *buf)
2535 {
2536
2537         unsigned int *ui = (unsigned int *) (((char *) sbi->s_es) +
2538                            a->u.offset);
2539
2540         return snprintf(buf, PAGE_SIZE, "%u\n", *ui);
2541 }
2542
2543 static ssize_t reserved_clusters_show(struct ext4_attr *a,
2544                                   struct ext4_sb_info *sbi, char *buf)
2545 {
2546         return snprintf(buf, PAGE_SIZE, "%llu\n",
2547                 (unsigned long long) atomic64_read(&sbi->s_resv_clusters));
2548 }
2549
2550 static ssize_t reserved_clusters_store(struct ext4_attr *a,
2551                                    struct ext4_sb_info *sbi,
2552                                    const char *buf, size_t count)
2553 {
2554         unsigned long long val;
2555         int ret;
2556
2557         if (parse_strtoull(buf, -1ULL, &val))
2558                 return -EINVAL;
2559         ret = ext4_reserve_clusters(sbi, val);
2560
2561         return ret ? ret : count;
2562 }
2563
2564 static ssize_t trigger_test_error(struct ext4_attr *a,
2565                                   struct ext4_sb_info *sbi,
2566                                   const char *buf, size_t count)
2567 {
2568         int len = count;
2569
2570         if (!capable(CAP_SYS_ADMIN))
2571                 return -EPERM;
2572
2573         if (len && buf[len-1] == '\n')
2574                 len--;
2575
2576         if (len)
2577                 ext4_error(sbi->s_sb, "%.*s", len, buf);
2578         return count;
2579 }
2580
2581 static ssize_t sbi_deprecated_show(struct ext4_attr *a,
2582                                    struct ext4_sb_info *sbi, char *buf)
2583 {
2584         return snprintf(buf, PAGE_SIZE, "%d\n", a->u.deprecated_val);
2585 }
2586
2587 #define EXT4_ATTR_OFFSET(_name,_mode,_show,_store,_elname) \
2588 static struct ext4_attr ext4_attr_##_name = {                   \
2589         .attr = {.name = __stringify(_name), .mode = _mode },   \
2590         .show   = _show,                                        \
2591         .store  = _store,                                       \
2592         .u = {                                                  \
2593                 .offset = offsetof(struct ext4_sb_info, _elname),\
2594         },                                                      \
2595 }
2596
2597 #define EXT4_ATTR_OFFSET_ES(_name,_mode,_show,_store,_elname)           \
2598 static struct ext4_attr ext4_attr_##_name = {                           \
2599         .attr = {.name = __stringify(_name), .mode = _mode },           \
2600         .show   = _show,                                                \
2601         .store  = _store,                                               \
2602         .u = {                                                          \
2603                 .offset = offsetof(struct ext4_super_block, _elname),   \
2604         },                                                              \
2605 }
2606
2607 #define EXT4_ATTR(name, mode, show, store) \
2608 static struct ext4_attr ext4_attr_##name = __ATTR(name, mode, show, store)
2609
2610 #define EXT4_INFO_ATTR(name) EXT4_ATTR(name, 0444, NULL, NULL)
2611 #define EXT4_RO_ATTR(name) EXT4_ATTR(name, 0444, name##_show, NULL)
2612 #define EXT4_RW_ATTR(name) EXT4_ATTR(name, 0644, name##_show, name##_store)
2613
2614 #define EXT4_RO_ATTR_ES_UI(name, elname)        \
2615         EXT4_ATTR_OFFSET_ES(name, 0444, es_ui_show, NULL, elname)
2616 #define EXT4_RW_ATTR_SBI_UI(name, elname)       \
2617         EXT4_ATTR_OFFSET(name, 0644, sbi_ui_show, sbi_ui_store, elname)
2618
2619 #define ATTR_LIST(name) &ext4_attr_##name.attr
2620 #define EXT4_DEPRECATED_ATTR(_name, _val)       \
2621 static struct ext4_attr ext4_attr_##_name = {                   \
2622         .attr = {.name = __stringify(_name), .mode = 0444 },    \
2623         .show   = sbi_deprecated_show,                          \
2624         .u = {                                                  \
2625                 .deprecated_val = _val,                         \
2626         },                                                      \
2627 }
2628
2629 EXT4_RO_ATTR(delayed_allocation_blocks);
2630 EXT4_RO_ATTR(session_write_kbytes);
2631 EXT4_RO_ATTR(lifetime_write_kbytes);
2632 EXT4_RW_ATTR(reserved_clusters);
2633 EXT4_ATTR_OFFSET(inode_readahead_blks, 0644, sbi_ui_show,
2634                  inode_readahead_blks_store, s_inode_readahead_blks);
2635 EXT4_RW_ATTR_SBI_UI(inode_goal, s_inode_goal);
2636 EXT4_RW_ATTR_SBI_UI(mb_stats, s_mb_stats);
2637 EXT4_RW_ATTR_SBI_UI(mb_max_to_scan, s_mb_max_to_scan);
2638 EXT4_RW_ATTR_SBI_UI(mb_min_to_scan, s_mb_min_to_scan);
2639 EXT4_RW_ATTR_SBI_UI(mb_order2_req, s_mb_order2_reqs);
2640 EXT4_RW_ATTR_SBI_UI(mb_stream_req, s_mb_stream_request);
2641 EXT4_RW_ATTR_SBI_UI(mb_group_prealloc, s_mb_group_prealloc);
2642 EXT4_DEPRECATED_ATTR(max_writeback_mb_bump, 128);
2643 EXT4_RW_ATTR_SBI_UI(extent_max_zeroout_kb, s_extent_max_zeroout_kb);
2644 EXT4_ATTR(trigger_fs_error, 0200, NULL, trigger_test_error);
2645 EXT4_RW_ATTR_SBI_UI(err_ratelimit_interval_ms, s_err_ratelimit_state.interval);
2646 EXT4_RW_ATTR_SBI_UI(err_ratelimit_burst, s_err_ratelimit_state.burst);
2647 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_interval_ms, s_warning_ratelimit_state.interval);
2648 EXT4_RW_ATTR_SBI_UI(warning_ratelimit_burst, s_warning_ratelimit_state.burst);
2649 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_interval_ms, s_msg_ratelimit_state.interval);
2650 EXT4_RW_ATTR_SBI_UI(msg_ratelimit_burst, s_msg_ratelimit_state.burst);
2651 EXT4_RO_ATTR_ES_UI(errors_count, s_error_count);
2652 EXT4_RO_ATTR_ES_UI(first_error_time, s_first_error_time);
2653 EXT4_RO_ATTR_ES_UI(last_error_time, s_last_error_time);
2654
2655 static struct attribute *ext4_attrs[] = {
2656         ATTR_LIST(delayed_allocation_blocks),
2657         ATTR_LIST(session_write_kbytes),
2658         ATTR_LIST(lifetime_write_kbytes),
2659         ATTR_LIST(reserved_clusters),
2660         ATTR_LIST(inode_readahead_blks),
2661         ATTR_LIST(inode_goal),
2662         ATTR_LIST(mb_stats),
2663         ATTR_LIST(mb_max_to_scan),
2664         ATTR_LIST(mb_min_to_scan),
2665         ATTR_LIST(mb_order2_req),
2666         ATTR_LIST(mb_stream_req),
2667         ATTR_LIST(mb_group_prealloc),
2668         ATTR_LIST(max_writeback_mb_bump),
2669         ATTR_LIST(extent_max_zeroout_kb),
2670         ATTR_LIST(trigger_fs_error),
2671         ATTR_LIST(err_ratelimit_interval_ms),
2672         ATTR_LIST(err_ratelimit_burst),
2673         ATTR_LIST(warning_ratelimit_interval_ms),
2674         ATTR_LIST(warning_ratelimit_burst),
2675         ATTR_LIST(msg_ratelimit_interval_ms),
2676         ATTR_LIST(msg_ratelimit_burst),
2677         ATTR_LIST(errors_count),
2678         ATTR_LIST(first_error_time),
2679         ATTR_LIST(last_error_time),
2680         NULL,
2681 };
2682
2683 /* Features this copy of ext4 supports */
2684 EXT4_INFO_ATTR(lazy_itable_init);
2685 EXT4_INFO_ATTR(batched_discard);
2686 EXT4_INFO_ATTR(meta_bg_resize);
2687 EXT4_INFO_ATTR(encryption);
2688
2689 static struct attribute *ext4_feat_attrs[] = {
2690         ATTR_LIST(lazy_itable_init),
2691         ATTR_LIST(batched_discard),
2692         ATTR_LIST(meta_bg_resize),
2693         ATTR_LIST(encryption),
2694         NULL,
2695 };
2696
2697 static ssize_t ext4_attr_show(struct kobject *kobj,
2698                               struct attribute *attr, char *buf)
2699 {
2700         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2701                                                 s_kobj);
2702         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2703
2704         return a->show ? a->show(a, sbi, buf) : 0;
2705 }
2706
2707 static ssize_t ext4_attr_store(struct kobject *kobj,
2708                                struct attribute *attr,
2709                                const char *buf, size_t len)
2710 {
2711         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2712                                                 s_kobj);
2713         struct ext4_attr *a = container_of(attr, struct ext4_attr, attr);
2714
2715         return a->store ? a->store(a, sbi, buf, len) : 0;
2716 }
2717
2718 static void ext4_sb_release(struct kobject *kobj)
2719 {
2720         struct ext4_sb_info *sbi = container_of(kobj, struct ext4_sb_info,
2721                                                 s_kobj);
2722         complete(&sbi->s_kobj_unregister);
2723 }
2724
2725 static const struct sysfs_ops ext4_attr_ops = {
2726         .show   = ext4_attr_show,
2727         .store  = ext4_attr_store,
2728 };
2729
2730 static struct kobj_type ext4_ktype = {
2731         .default_attrs  = ext4_attrs,
2732         .sysfs_ops      = &ext4_attr_ops,
2733         .release        = ext4_sb_release,
2734 };
2735
2736 static void ext4_feat_release(struct kobject *kobj)
2737 {
2738         complete(&ext4_feat->f_kobj_unregister);
2739 }
2740
2741 static ssize_t ext4_feat_show(struct kobject *kobj,
2742                               struct attribute *attr, char *buf)
2743 {
2744         return snprintf(buf, PAGE_SIZE, "supported\n");
2745 }
2746
2747 /*
2748  * We can not use ext4_attr_show/store because it relies on the kobject
2749  * being embedded in the ext4_sb_info structure which is definitely not
2750  * true in this case.
2751  */
2752 static const struct sysfs_ops ext4_feat_ops = {
2753         .show   = ext4_feat_show,
2754         .store  = NULL,
2755 };
2756
2757 static struct kobj_type ext4_feat_ktype = {
2758         .default_attrs  = ext4_feat_attrs,
2759         .sysfs_ops      = &ext4_feat_ops,
2760         .release        = ext4_feat_release,
2761 };
2762
2763 /*
2764  * Check whether this filesystem can be mounted based on
2765  * the features present and the RDONLY/RDWR mount requested.
2766  * Returns 1 if this filesystem can be mounted as requested,
2767  * 0 if it cannot be.
2768  */
2769 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2770 {
2771         if (EXT4_HAS_INCOMPAT_FEATURE(sb, ~EXT4_FEATURE_INCOMPAT_SUPP)) {
2772                 ext4_msg(sb, KERN_ERR,
2773                         "Couldn't mount because of "
2774                         "unsupported optional features (%x)",
2775                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2776                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2777                 return 0;
2778         }
2779
2780         if (readonly)
2781                 return 1;
2782
2783         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_READONLY)) {
2784                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2785                 sb->s_flags |= MS_RDONLY;
2786                 return 1;
2787         }
2788
2789         /* Check that feature set is OK for a read-write mount */
2790         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, ~EXT4_FEATURE_RO_COMPAT_SUPP)) {
2791                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2792                          "unsupported optional features (%x)",
2793                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2794                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2795                 return 0;
2796         }
2797         /*
2798          * Large file size enabled file system can only be mounted
2799          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2800          */
2801         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_HUGE_FILE)) {
2802                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2803                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2804                                  "cannot be mounted RDWR without "
2805                                  "CONFIG_LBDAF");
2806                         return 0;
2807                 }
2808         }
2809         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_BIGALLOC) &&
2810             !EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_EXTENTS)) {
2811                 ext4_msg(sb, KERN_ERR,
2812                          "Can't support bigalloc feature without "
2813                          "extents feature\n");
2814                 return 0;
2815         }
2816
2817 #ifndef CONFIG_QUOTA
2818         if (EXT4_HAS_RO_COMPAT_FEATURE(sb, EXT4_FEATURE_RO_COMPAT_QUOTA) &&
2819             !readonly) {
2820                 ext4_msg(sb, KERN_ERR,
2821                          "Filesystem with quota feature cannot be mounted RDWR "
2822                          "without CONFIG_QUOTA");
2823                 return 0;
2824         }
2825 #endif  /* CONFIG_QUOTA */
2826         return 1;
2827 }
2828
2829 /*
2830  * This function is called once a day if we have errors logged
2831  * on the file system
2832  */
2833 static void print_daily_error_info(unsigned long arg)
2834 {
2835         struct super_block *sb = (struct super_block *) arg;
2836         struct ext4_sb_info *sbi;
2837         struct ext4_super_block *es;
2838
2839         sbi = EXT4_SB(sb);
2840         es = sbi->s_es;
2841
2842         if (es->s_error_count)
2843                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2844                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2845                          le32_to_cpu(es->s_error_count));
2846         if (es->s_first_error_time) {
2847                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2848                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2849                        (int) sizeof(es->s_first_error_func),
2850                        es->s_first_error_func,
2851                        le32_to_cpu(es->s_first_error_line));
2852                 if (es->s_first_error_ino)
2853                         printk(": inode %u",
2854                                le32_to_cpu(es->s_first_error_ino));
2855                 if (es->s_first_error_block)
2856                         printk(": block %llu", (unsigned long long)
2857                                le64_to_cpu(es->s_first_error_block));
2858                 printk("\n");
2859         }
2860         if (es->s_last_error_time) {
2861                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2862                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2863                        (int) sizeof(es->s_last_error_func),
2864                        es->s_last_error_func,
2865                        le32_to_cpu(es->s_last_error_line));
2866                 if (es->s_last_error_ino)
2867                         printk(": inode %u",
2868                                le32_to_cpu(es->s_last_error_ino));
2869                 if (es->s_last_error_block)
2870                         printk(": block %llu", (unsigned long long)
2871                                le64_to_cpu(es->s_last_error_block));
2872                 printk("\n");
2873         }
2874         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2875 }
2876
2877 /* Find next suitable group and run ext4_init_inode_table */
2878 static int ext4_run_li_request(struct ext4_li_request *elr)
2879 {
2880         struct ext4_group_desc *gdp = NULL;
2881         ext4_group_t group, ngroups;
2882         struct super_block *sb;
2883         unsigned long timeout = 0;
2884         int ret = 0;
2885
2886         sb = elr->lr_super;
2887         ngroups = EXT4_SB(sb)->s_groups_count;
2888
2889         sb_start_write(sb);
2890         for (group = elr->lr_next_group; group < ngroups; group++) {
2891                 gdp = ext4_get_group_desc(sb, group, NULL);
2892                 if (!gdp) {
2893                         ret = 1;
2894                         break;
2895                 }
2896
2897                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2898                         break;
2899         }
2900
2901         if (group >= ngroups)
2902                 ret = 1;
2903
2904         if (!ret) {
2905                 timeout = jiffies;
2906                 ret = ext4_init_inode_table(sb, group,
2907                                             elr->lr_timeout ? 0 : 1);
2908                 if (elr->lr_timeout == 0) {
2909                         timeout = (jiffies - timeout) *
2910                                   elr->lr_sbi->s_li_wait_mult;
2911                         elr->lr_timeout = timeout;
2912                 }
2913                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2914                 elr->lr_next_group = group + 1;
2915         }
2916         sb_end_write(sb);
2917
2918         return ret;
2919 }
2920
2921 /*
2922  * Remove lr_request from the list_request and free the
2923  * request structure. Should be called with li_list_mtx held
2924  */
2925 static void ext4_remove_li_request(struct ext4_li_request *elr)
2926 {
2927         struct ext4_sb_info *sbi;
2928
2929         if (!elr)
2930                 return;
2931
2932         sbi = elr->lr_sbi;
2933
2934         list_del(&elr->lr_request);
2935         sbi->s_li_request = NULL;
2936         kfree(elr);
2937 }
2938
2939 static void ext4_unregister_li_request(struct super_block *sb)
2940 {
2941         mutex_lock(&ext4_li_mtx);
2942         if (!ext4_li_info) {
2943                 mutex_unlock(&ext4_li_mtx);
2944                 return;
2945         }
2946
2947         mutex_lock(&ext4_li_info->li_list_mtx);
2948         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2949         mutex_unlock(&ext4_li_info->li_list_mtx);
2950         mutex_unlock(&ext4_li_mtx);
2951 }
2952
2953 static struct task_struct *ext4_lazyinit_task;
2954
2955 /*
2956  * This is the function where ext4lazyinit thread lives. It walks
2957  * through the request list searching for next scheduled filesystem.
2958  * When such a fs is found, run the lazy initialization request
2959  * (ext4_rn_li_request) and keep track of the time spend in this
2960  * function. Based on that time we compute next schedule time of
2961  * the request. When walking through the list is complete, compute
2962  * next waking time and put itself into sleep.
2963  */
2964 static int ext4_lazyinit_thread(void *arg)
2965 {
2966         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2967         struct list_head *pos, *n;
2968         struct ext4_li_request *elr;
2969         unsigned long next_wakeup, cur;
2970
2971         BUG_ON(NULL == eli);
2972
2973 cont_thread:
2974         while (true) {
2975                 next_wakeup = MAX_JIFFY_OFFSET;
2976
2977                 mutex_lock(&eli->li_list_mtx);
2978                 if (list_empty(&eli->li_request_list)) {
2979                         mutex_unlock(&eli->li_list_mtx);
2980                         goto exit_thread;
2981                 }
2982
2983                 list_for_each_safe(pos, n, &eli->li_request_list) {
2984                         elr = list_entry(pos, struct ext4_li_request,
2985                                          lr_request);
2986
2987                         if (time_after_eq(jiffies, elr->lr_next_sched)) {
2988                                 if (ext4_run_li_request(elr) != 0) {
2989                                         /* error, remove the lazy_init job */
2990                                         ext4_remove_li_request(elr);
2991                                         continue;
2992                                 }
2993                         }
2994
2995                         if (time_before(elr->lr_next_sched, next_wakeup))
2996                                 next_wakeup = elr->lr_next_sched;
2997                 }
2998                 mutex_unlock(&eli->li_list_mtx);
2999
3000                 try_to_freeze();
3001
3002                 cur = jiffies;
3003                 if ((time_after_eq(cur, next_wakeup)) ||
3004                     (MAX_JIFFY_OFFSET == next_wakeup)) {
3005                         cond_resched();
3006                         continue;
3007                 }
3008
3009                 schedule_timeout_interruptible(next_wakeup - cur);
3010
3011                 if (kthread_should_stop()) {
3012                         ext4_clear_request_list();
3013                         goto exit_thread;
3014                 }
3015         }
3016
3017 exit_thread:
3018         /*
3019          * It looks like the request list is empty, but we need
3020          * to check it under the li_list_mtx lock, to prevent any
3021          * additions into it, and of course we should lock ext4_li_mtx
3022          * to atomically free the list and ext4_li_info, because at
3023          * this point another ext4 filesystem could be registering
3024          * new one.
3025          */
3026         mutex_lock(&ext4_li_mtx);
3027         mutex_lock(&eli->li_list_mtx);
3028         if (!list_empty(&eli->li_request_list)) {
3029                 mutex_unlock(&eli->li_list_mtx);
3030                 mutex_unlock(&ext4_li_mtx);
3031                 goto cont_thread;
3032         }
3033         mutex_unlock(&eli->li_list_mtx);
3034         kfree(ext4_li_info);
3035         ext4_li_info = NULL;
3036         mutex_unlock(&ext4_li_mtx);
3037
3038         return 0;
3039 }
3040
3041 static void ext4_clear_request_list(void)
3042 {
3043         struct list_head *pos, *n;
3044         struct ext4_li_request *elr;
3045
3046         mutex_lock(&ext4_li_info->li_list_mtx);
3047         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3048                 elr = list_entry(pos, struct ext4_li_request,
3049                                  lr_request);
3050                 ext4_remove_li_request(elr);
3051         }
3052         mutex_unlock(&ext4_li_info->li_list_mtx);
3053 }
3054
3055 static int ext4_run_lazyinit_thread(void)
3056 {
3057         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3058                                          ext4_li_info, "ext4lazyinit");
3059         if (IS_ERR(ext4_lazyinit_task)) {
3060                 int err = PTR_ERR(ext4_lazyinit_task);
3061                 ext4_clear_request_list();
3062                 kfree(ext4_li_info);
3063                 ext4_li_info = NULL;
3064                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3065                                  "initialization thread\n",
3066                                  err);
3067                 return err;
3068         }
3069         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3070         return 0;
3071 }
3072
3073 /*
3074  * Check whether it make sense to run itable init. thread or not.
3075  * If there is at least one uninitialized inode table, return
3076  * corresponding group number, else the loop goes through all
3077  * groups and return total number of groups.
3078  */
3079 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3080 {
3081         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3082         struct ext4_group_desc *gdp = NULL;
3083
3084         for (group = 0; group < ngroups; group++) {
3085                 gdp = ext4_get_group_desc(sb, group, NULL);
3086                 if (!gdp)
3087                         continue;
3088
3089                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3090                         break;
3091         }
3092
3093         return group;
3094 }
3095
3096 static int ext4_li_info_new(void)
3097 {
3098         struct ext4_lazy_init *eli = NULL;
3099
3100         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3101         if (!eli)
3102                 return -ENOMEM;
3103
3104         INIT_LIST_HEAD(&eli->li_request_list);
3105         mutex_init(&eli->li_list_mtx);
3106
3107         eli->li_state |= EXT4_LAZYINIT_QUIT;
3108
3109         ext4_li_info = eli;
3110
3111         return 0;
3112 }
3113
3114 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3115                                             ext4_group_t start)
3116 {
3117         struct ext4_sb_info *sbi = EXT4_SB(sb);
3118         struct ext4_li_request *elr;
3119
3120         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3121         if (!elr)
3122                 return NULL;
3123
3124         elr->lr_super = sb;
3125         elr->lr_sbi = sbi;
3126         elr->lr_next_group = start;
3127
3128         /*
3129          * Randomize first schedule time of the request to
3130          * spread the inode table initialization requests
3131          * better.
3132          */
3133         elr->lr_next_sched = jiffies + (prandom_u32() %
3134                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3135         return elr;
3136 }
3137
3138 int ext4_register_li_request(struct super_block *sb,
3139                              ext4_group_t first_not_zeroed)
3140 {
3141         struct ext4_sb_info *sbi = EXT4_SB(sb);
3142         struct ext4_li_request *elr = NULL;
3143         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3144         int ret = 0;
3145
3146         mutex_lock(&ext4_li_mtx);
3147         if (sbi->s_li_request != NULL) {
3148                 /*
3149                  * Reset timeout so it can be computed again, because
3150                  * s_li_wait_mult might have changed.
3151                  */
3152                 sbi->s_li_request->lr_timeout = 0;
3153                 goto out;
3154         }
3155
3156         if (first_not_zeroed == ngroups ||
3157             (sb->s_flags & MS_RDONLY) ||
3158             !test_opt(sb, INIT_INODE_TABLE))
3159                 goto out;
3160
3161         elr = ext4_li_request_new(sb, first_not_zeroed);
3162         if (!elr) {
3163                 ret = -ENOMEM;
3164                 goto out;
3165         }
3166
3167         if (NULL == ext4_li_info) {
3168                 ret = ext4_li_info_new();
3169                 if (ret)
3170                         goto out;
3171         }
3172
3173         mutex_lock(&ext4_li_info->li_list_mtx);
3174         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3175         mutex_unlock(&ext4_li_info->li_list_mtx);
3176
3177         sbi->s_li_request = elr;
3178         /*
3179          * set elr to NULL here since it has been inserted to
3180          * the request_list and the removal and free of it is
3181          * handled by ext4_clear_request_list from now on.
3182          */
3183         elr = NULL;
3184
3185         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3186                 ret = ext4_run_lazyinit_thread();
3187                 if (ret)
3188                         goto out;
3189         }
3190 out:
3191         mutex_unlock(&ext4_li_mtx);
3192         if (ret)
3193                 kfree(elr);
3194         return ret;
3195 }
3196
3197 /*
3198  * We do not need to lock anything since this is called on
3199  * module unload.
3200  */
3201 static void ext4_destroy_lazyinit_thread(void)
3202 {
3203         /*
3204          * If thread exited earlier
3205          * there's nothing to be done.
3206          */
3207         if (!ext4_li_info || !ext4_lazyinit_task)
3208                 return;
3209
3210         kthread_stop(ext4_lazyinit_task);
3211 }
3212
3213 static int set_journal_csum_feature_set(struct super_block *sb)
3214 {
3215         int ret = 1;
3216         int compat, incompat;
3217         struct ext4_sb_info *sbi = EXT4_SB(sb);
3218
3219         if (ext4_has_metadata_csum(sb)) {
3220                 /* journal checksum v3 */
3221                 compat = 0;
3222                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3223         } else {
3224                 /* journal checksum v1 */
3225                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3226                 incompat = 0;
3227         }
3228
3229         jbd2_journal_clear_features(sbi->s_journal,
3230                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3231                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3232                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3233         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3234                 ret = jbd2_journal_set_features(sbi->s_journal,
3235                                 compat, 0,
3236                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3237                                 incompat);
3238         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3239                 ret = jbd2_journal_set_features(sbi->s_journal,
3240                                 compat, 0,
3241                                 incompat);
3242                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3243                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3244         } else {
3245                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3246                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3247         }
3248
3249         return ret;
3250 }
3251
3252 /*
3253  * Note: calculating the overhead so we can be compatible with
3254  * historical BSD practice is quite difficult in the face of
3255  * clusters/bigalloc.  This is because multiple metadata blocks from
3256  * different block group can end up in the same allocation cluster.
3257  * Calculating the exact overhead in the face of clustered allocation
3258  * requires either O(all block bitmaps) in memory or O(number of block
3259  * groups**2) in time.