2 * linux/fs/ext2/super.c
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)
11 * linux/fs/minix/inode.c
13 * Copyright (C) 1991, 1992 Linus Torvalds
15 * Big-endian to little-endian byte-swapping/bitmaps by
16 * David S. Miller (davem@caip.rutgers.edu), 1995
19 #include <linux/module.h>
20 #include <linux/string.h>
22 #include <linux/slab.h>
23 #include <linux/init.h>
24 #include <linux/blkdev.h>
25 #include <linux/parser.h>
26 #include <linux/random.h>
27 #include <linux/buffer_head.h>
28 #include <linux/exportfs.h>
29 #include <linux/vfs.h>
30 #include <linux/seq_file.h>
31 #include <linux/mount.h>
32 #include <linux/log2.h>
33 #include <linux/quotaops.h>
34 #include <asm/uaccess.h>
40 static void ext2_sync_super(struct super_block
*sb
,
41 struct ext2_super_block
*es
, int wait
);
42 static int ext2_remount (struct super_block
* sb
, int * flags
, char * data
);
43 static int ext2_statfs (struct dentry
* dentry
, struct kstatfs
* buf
);
44 static int ext2_sync_fs(struct super_block
*sb
, int wait
);
46 void ext2_error(struct super_block
*sb
, const char *function
,
51 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
52 struct ext2_super_block
*es
= sbi
->s_es
;
54 if (!(sb
->s_flags
& MS_RDONLY
)) {
55 spin_lock(&sbi
->s_lock
);
56 sbi
->s_mount_state
|= EXT2_ERROR_FS
;
57 es
->s_state
|= cpu_to_le16(EXT2_ERROR_FS
);
58 spin_unlock(&sbi
->s_lock
);
59 ext2_sync_super(sb
, es
, 1);
67 printk(KERN_CRIT
"EXT2-fs (%s): error: %s: %pV\n",
68 sb
->s_id
, function
, &vaf
);
72 if (test_opt(sb
, ERRORS_PANIC
))
73 panic("EXT2-fs: panic from previous error\n");
74 if (test_opt(sb
, ERRORS_RO
)) {
75 ext2_msg(sb
, KERN_CRIT
,
76 "error: remounting filesystem read-only");
77 sb
->s_flags
|= MS_RDONLY
;
81 void ext2_msg(struct super_block
*sb
, const char *prefix
,
92 printk("%sEXT2-fs (%s): %pV\n", prefix
, sb
->s_id
, &vaf
);
98 * This must be called with sbi->s_lock held.
100 void ext2_update_dynamic_rev(struct super_block
*sb
)
102 struct ext2_super_block
*es
= EXT2_SB(sb
)->s_es
;
104 if (le32_to_cpu(es
->s_rev_level
) > EXT2_GOOD_OLD_REV
)
107 ext2_msg(sb
, KERN_WARNING
,
108 "warning: updating to rev %d because of "
109 "new feature flag, running e2fsck is recommended",
112 es
->s_first_ino
= cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO
);
113 es
->s_inode_size
= cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE
);
114 es
->s_rev_level
= cpu_to_le32(EXT2_DYNAMIC_REV
);
115 /* leave es->s_feature_*compat flags alone */
116 /* es->s_uuid will be set by e2fsck if empty */
119 * The rest of the superblock fields should be zero, and if not it
120 * means they are likely already in use, so leave them alone. We
121 * can leave it up to e2fsck to clean up any inconsistencies there.
125 static void ext2_put_super (struct super_block
* sb
)
129 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
131 dquot_disable(sb
, -1, DQUOT_USAGE_ENABLED
| DQUOT_LIMITS_ENABLED
);
134 ext2_write_super(sb
);
136 ext2_xattr_put_super(sb
);
137 if (!(sb
->s_flags
& MS_RDONLY
)) {
138 struct ext2_super_block
*es
= sbi
->s_es
;
140 spin_lock(&sbi
->s_lock
);
141 es
->s_state
= cpu_to_le16(sbi
->s_mount_state
);
142 spin_unlock(&sbi
->s_lock
);
143 ext2_sync_super(sb
, es
, 1);
145 db_count
= sbi
->s_gdb_count
;
146 for (i
= 0; i
< db_count
; i
++)
147 if (sbi
->s_group_desc
[i
])
148 brelse (sbi
->s_group_desc
[i
]);
149 kfree(sbi
->s_group_desc
);
151 percpu_counter_destroy(&sbi
->s_freeblocks_counter
);
152 percpu_counter_destroy(&sbi
->s_freeinodes_counter
);
153 percpu_counter_destroy(&sbi
->s_dirs_counter
);
155 sb
->s_fs_info
= NULL
;
156 kfree(sbi
->s_blockgroup_lock
);
160 static struct kmem_cache
* ext2_inode_cachep
;
162 static struct inode
*ext2_alloc_inode(struct super_block
*sb
)
164 struct ext2_inode_info
*ei
;
165 ei
= (struct ext2_inode_info
*)kmem_cache_alloc(ext2_inode_cachep
, GFP_KERNEL
);
168 ei
->i_block_alloc_info
= NULL
;
169 ei
->vfs_inode
.i_version
= 1;
170 return &ei
->vfs_inode
;
173 static void ext2_i_callback(struct rcu_head
*head
)
175 struct inode
*inode
= container_of(head
, struct inode
, i_rcu
);
176 INIT_LIST_HEAD(&inode
->i_dentry
);
177 kmem_cache_free(ext2_inode_cachep
, EXT2_I(inode
));
180 static void ext2_destroy_inode(struct inode
*inode
)
182 call_rcu(&inode
->i_rcu
, ext2_i_callback
);
185 static void init_once(void *foo
)
187 struct ext2_inode_info
*ei
= (struct ext2_inode_info
*) foo
;
189 rwlock_init(&ei
->i_meta_lock
);
190 #ifdef CONFIG_EXT2_FS_XATTR
191 init_rwsem(&ei
->xattr_sem
);
193 mutex_init(&ei
->truncate_mutex
);
194 inode_init_once(&ei
->vfs_inode
);
197 static int init_inodecache(void)
199 ext2_inode_cachep
= kmem_cache_create("ext2_inode_cache",
200 sizeof(struct ext2_inode_info
),
201 0, (SLAB_RECLAIM_ACCOUNT
|
204 if (ext2_inode_cachep
== NULL
)
209 static void destroy_inodecache(void)
211 kmem_cache_destroy(ext2_inode_cachep
);
214 static int ext2_show_options(struct seq_file
*seq
, struct vfsmount
*vfs
)
216 struct super_block
*sb
= vfs
->mnt_sb
;
217 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
218 struct ext2_super_block
*es
= sbi
->s_es
;
219 unsigned long def_mount_opts
;
221 spin_lock(&sbi
->s_lock
);
222 def_mount_opts
= le32_to_cpu(es
->s_default_mount_opts
);
224 if (sbi
->s_sb_block
!= 1)
225 seq_printf(seq
, ",sb=%lu", sbi
->s_sb_block
);
226 if (test_opt(sb
, MINIX_DF
))
227 seq_puts(seq
, ",minixdf");
228 if (test_opt(sb
, GRPID
))
229 seq_puts(seq
, ",grpid");
230 if (!test_opt(sb
, GRPID
) && (def_mount_opts
& EXT2_DEFM_BSDGROUPS
))
231 seq_puts(seq
, ",nogrpid");
232 if (sbi
->s_resuid
!= EXT2_DEF_RESUID
||
233 le16_to_cpu(es
->s_def_resuid
) != EXT2_DEF_RESUID
) {
234 seq_printf(seq
, ",resuid=%u", sbi
->s_resuid
);
236 if (sbi
->s_resgid
!= EXT2_DEF_RESGID
||
237 le16_to_cpu(es
->s_def_resgid
) != EXT2_DEF_RESGID
) {
238 seq_printf(seq
, ",resgid=%u", sbi
->s_resgid
);
240 if (test_opt(sb
, ERRORS_RO
)) {
241 int def_errors
= le16_to_cpu(es
->s_errors
);
243 if (def_errors
== EXT2_ERRORS_PANIC
||
244 def_errors
== EXT2_ERRORS_CONTINUE
) {
245 seq_puts(seq
, ",errors=remount-ro");
248 if (test_opt(sb
, ERRORS_CONT
))
249 seq_puts(seq
, ",errors=continue");
250 if (test_opt(sb
, ERRORS_PANIC
))
251 seq_puts(seq
, ",errors=panic");
252 if (test_opt(sb
, NO_UID32
))
253 seq_puts(seq
, ",nouid32");
254 if (test_opt(sb
, DEBUG
))
255 seq_puts(seq
, ",debug");
256 if (test_opt(sb
, OLDALLOC
))
257 seq_puts(seq
, ",oldalloc");
259 #ifdef CONFIG_EXT2_FS_XATTR
260 if (test_opt(sb
, XATTR_USER
))
261 seq_puts(seq
, ",user_xattr");
262 if (!test_opt(sb
, XATTR_USER
) &&
263 (def_mount_opts
& EXT2_DEFM_XATTR_USER
)) {
264 seq_puts(seq
, ",nouser_xattr");
268 #ifdef CONFIG_EXT2_FS_POSIX_ACL
269 if (test_opt(sb
, POSIX_ACL
))
270 seq_puts(seq
, ",acl");
271 if (!test_opt(sb
, POSIX_ACL
) && (def_mount_opts
& EXT2_DEFM_ACL
))
272 seq_puts(seq
, ",noacl");
275 if (test_opt(sb
, NOBH
))
276 seq_puts(seq
, ",nobh");
278 #if defined(CONFIG_QUOTA)
279 if (sbi
->s_mount_opt
& EXT2_MOUNT_USRQUOTA
)
280 seq_puts(seq
, ",usrquota");
282 if (sbi
->s_mount_opt
& EXT2_MOUNT_GRPQUOTA
)
283 seq_puts(seq
, ",grpquota");
286 #if defined(CONFIG_EXT2_FS_XIP)
287 if (sbi
->s_mount_opt
& EXT2_MOUNT_XIP
)
288 seq_puts(seq
, ",xip");
291 if (!test_opt(sb
, RESERVATION
))
292 seq_puts(seq
, ",noreservation");
294 spin_unlock(&sbi
->s_lock
);
299 static ssize_t
ext2_quota_read(struct super_block
*sb
, int type
, char *data
, size_t len
, loff_t off
);
300 static ssize_t
ext2_quota_write(struct super_block
*sb
, int type
, const char *data
, size_t len
, loff_t off
);
303 static const struct super_operations ext2_sops
= {
304 .alloc_inode
= ext2_alloc_inode
,
305 .destroy_inode
= ext2_destroy_inode
,
306 .write_inode
= ext2_write_inode
,
307 .evict_inode
= ext2_evict_inode
,
308 .put_super
= ext2_put_super
,
309 .write_super
= ext2_write_super
,
310 .sync_fs
= ext2_sync_fs
,
311 .statfs
= ext2_statfs
,
312 .remount_fs
= ext2_remount
,
313 .show_options
= ext2_show_options
,
315 .quota_read
= ext2_quota_read
,
316 .quota_write
= ext2_quota_write
,
320 static struct inode
*ext2_nfs_get_inode(struct super_block
*sb
,
321 u64 ino
, u32 generation
)
325 if (ino
< EXT2_FIRST_INO(sb
) && ino
!= EXT2_ROOT_INO
)
326 return ERR_PTR(-ESTALE
);
327 if (ino
> le32_to_cpu(EXT2_SB(sb
)->s_es
->s_inodes_count
))
328 return ERR_PTR(-ESTALE
);
330 /* iget isn't really right if the inode is currently unallocated!!
331 * ext2_read_inode currently does appropriate checks, but
332 * it might be "neater" to call ext2_get_inode first and check
333 * if the inode is valid.....
335 inode
= ext2_iget(sb
, ino
);
337 return ERR_CAST(inode
);
338 if (generation
&& inode
->i_generation
!= generation
) {
339 /* we didn't find the right inode.. */
341 return ERR_PTR(-ESTALE
);
346 static struct dentry
*ext2_fh_to_dentry(struct super_block
*sb
, struct fid
*fid
,
347 int fh_len
, int fh_type
)
349 return generic_fh_to_dentry(sb
, fid
, fh_len
, fh_type
,
353 static struct dentry
*ext2_fh_to_parent(struct super_block
*sb
, struct fid
*fid
,
354 int fh_len
, int fh_type
)
356 return generic_fh_to_parent(sb
, fid
, fh_len
, fh_type
,
360 /* Yes, most of these are left as NULL!!
361 * A NULL value implies the default, which works with ext2-like file
362 * systems, but can be improved upon.
363 * Currently only get_parent is required.
365 static const struct export_operations ext2_export_ops
= {
366 .fh_to_dentry
= ext2_fh_to_dentry
,
367 .fh_to_parent
= ext2_fh_to_parent
,
368 .get_parent
= ext2_get_parent
,
371 static unsigned long get_sb_block(void **data
)
373 unsigned long sb_block
;
374 char *options
= (char *) *data
;
376 if (!options
|| strncmp(options
, "sb=", 3) != 0)
377 return 1; /* Default location */
379 sb_block
= simple_strtoul(options
, &options
, 0);
380 if (*options
&& *options
!= ',') {
381 printk("EXT2-fs: Invalid sb specification: %s\n",
387 *data
= (void *) options
;
392 Opt_bsd_df
, Opt_minix_df
, Opt_grpid
, Opt_nogrpid
,
393 Opt_resgid
, Opt_resuid
, Opt_sb
, Opt_err_cont
, Opt_err_panic
,
394 Opt_err_ro
, Opt_nouid32
, Opt_nocheck
, Opt_debug
,
395 Opt_oldalloc
, Opt_orlov
, Opt_nobh
, Opt_user_xattr
, Opt_nouser_xattr
,
396 Opt_acl
, Opt_noacl
, Opt_xip
, Opt_ignore
, Opt_err
, Opt_quota
,
397 Opt_usrquota
, Opt_grpquota
, Opt_reservation
, Opt_noreservation
400 static const match_table_t tokens
= {
401 {Opt_bsd_df
, "bsddf"},
402 {Opt_minix_df
, "minixdf"},
403 {Opt_grpid
, "grpid"},
404 {Opt_grpid
, "bsdgroups"},
405 {Opt_nogrpid
, "nogrpid"},
406 {Opt_nogrpid
, "sysvgroups"},
407 {Opt_resgid
, "resgid=%u"},
408 {Opt_resuid
, "resuid=%u"},
410 {Opt_err_cont
, "errors=continue"},
411 {Opt_err_panic
, "errors=panic"},
412 {Opt_err_ro
, "errors=remount-ro"},
413 {Opt_nouid32
, "nouid32"},
414 {Opt_nocheck
, "check=none"},
415 {Opt_nocheck
, "nocheck"},
416 {Opt_debug
, "debug"},
417 {Opt_oldalloc
, "oldalloc"},
418 {Opt_orlov
, "orlov"},
420 {Opt_user_xattr
, "user_xattr"},
421 {Opt_nouser_xattr
, "nouser_xattr"},
423 {Opt_noacl
, "noacl"},
425 {Opt_grpquota
, "grpquota"},
426 {Opt_ignore
, "noquota"},
427 {Opt_quota
, "quota"},
428 {Opt_usrquota
, "usrquota"},
429 {Opt_reservation
, "reservation"},
430 {Opt_noreservation
, "noreservation"},
434 static int parse_options(char *options
, struct super_block
*sb
)
437 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
438 substring_t args
[MAX_OPT_ARGS
];
444 while ((p
= strsep (&options
, ",")) != NULL
) {
449 token
= match_token(p
, tokens
, args
);
452 clear_opt (sbi
->s_mount_opt
, MINIX_DF
);
455 set_opt (sbi
->s_mount_opt
, MINIX_DF
);
458 set_opt (sbi
->s_mount_opt
, GRPID
);
461 clear_opt (sbi
->s_mount_opt
, GRPID
);
464 if (match_int(&args
[0], &option
))
466 sbi
->s_resuid
= option
;
469 if (match_int(&args
[0], &option
))
471 sbi
->s_resgid
= option
;
474 /* handled by get_sb_block() instead of here */
475 /* *sb_block = match_int(&args[0]); */
478 clear_opt (sbi
->s_mount_opt
, ERRORS_CONT
);
479 clear_opt (sbi
->s_mount_opt
, ERRORS_RO
);
480 set_opt (sbi
->s_mount_opt
, ERRORS_PANIC
);
483 clear_opt (sbi
->s_mount_opt
, ERRORS_CONT
);
484 clear_opt (sbi
->s_mount_opt
, ERRORS_PANIC
);
485 set_opt (sbi
->s_mount_opt
, ERRORS_RO
);
488 clear_opt (sbi
->s_mount_opt
, ERRORS_RO
);
489 clear_opt (sbi
->s_mount_opt
, ERRORS_PANIC
);
490 set_opt (sbi
->s_mount_opt
, ERRORS_CONT
);
493 set_opt (sbi
->s_mount_opt
, NO_UID32
);
496 clear_opt (sbi
->s_mount_opt
, CHECK
);
499 set_opt (sbi
->s_mount_opt
, DEBUG
);
502 set_opt (sbi
->s_mount_opt
, OLDALLOC
);
505 clear_opt (sbi
->s_mount_opt
, OLDALLOC
);
508 set_opt (sbi
->s_mount_opt
, NOBH
);
510 #ifdef CONFIG_EXT2_FS_XATTR
512 set_opt (sbi
->s_mount_opt
, XATTR_USER
);
514 case Opt_nouser_xattr
:
515 clear_opt (sbi
->s_mount_opt
, XATTR_USER
);
519 case Opt_nouser_xattr
:
520 ext2_msg(sb
, KERN_INFO
, "(no)user_xattr options"
524 #ifdef CONFIG_EXT2_FS_POSIX_ACL
526 set_opt(sbi
->s_mount_opt
, POSIX_ACL
);
529 clear_opt(sbi
->s_mount_opt
, POSIX_ACL
);
534 ext2_msg(sb
, KERN_INFO
,
535 "(no)acl options not supported");
539 #ifdef CONFIG_EXT2_FS_XIP
540 set_opt (sbi
->s_mount_opt
, XIP
);
542 ext2_msg(sb
, KERN_INFO
, "xip option not supported");
546 #if defined(CONFIG_QUOTA)
549 set_opt(sbi
->s_mount_opt
, USRQUOTA
);
553 set_opt(sbi
->s_mount_opt
, GRPQUOTA
);
559 ext2_msg(sb
, KERN_INFO
,
560 "quota operations not supported");
564 case Opt_reservation
:
565 set_opt(sbi
->s_mount_opt
, RESERVATION
);
566 ext2_msg(sb
, KERN_INFO
, "reservations ON");
568 case Opt_noreservation
:
569 clear_opt(sbi
->s_mount_opt
, RESERVATION
);
570 ext2_msg(sb
, KERN_INFO
, "reservations OFF");
581 static int ext2_setup_super (struct super_block
* sb
,
582 struct ext2_super_block
* es
,
586 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
588 if (le32_to_cpu(es
->s_rev_level
) > EXT2_MAX_SUPP_REV
) {
589 ext2_msg(sb
, KERN_ERR
,
590 "error: revision level too high, "
591 "forcing read-only mode");
596 if (!(sbi
->s_mount_state
& EXT2_VALID_FS
))
597 ext2_msg(sb
, KERN_WARNING
,
598 "warning: mounting unchecked fs, "
599 "running e2fsck is recommended");
600 else if ((sbi
->s_mount_state
& EXT2_ERROR_FS
))
601 ext2_msg(sb
, KERN_WARNING
,
602 "warning: mounting fs with errors, "
603 "running e2fsck is recommended");
604 else if ((__s16
) le16_to_cpu(es
->s_max_mnt_count
) >= 0 &&
605 le16_to_cpu(es
->s_mnt_count
) >=
606 (unsigned short) (__s16
) le16_to_cpu(es
->s_max_mnt_count
))
607 ext2_msg(sb
, KERN_WARNING
,
608 "warning: maximal mount count reached, "
609 "running e2fsck is recommended");
610 else if (le32_to_cpu(es
->s_checkinterval
) &&
611 (le32_to_cpu(es
->s_lastcheck
) +
612 le32_to_cpu(es
->s_checkinterval
) <= get_seconds()))
613 ext2_msg(sb
, KERN_WARNING
,
614 "warning: checktime reached, "
615 "running e2fsck is recommended");
616 if (!le16_to_cpu(es
->s_max_mnt_count
))
617 es
->s_max_mnt_count
= cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT
);
618 le16_add_cpu(&es
->s_mnt_count
, 1);
619 if (test_opt (sb
, DEBUG
))
620 ext2_msg(sb
, KERN_INFO
, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
621 "bpg=%lu, ipg=%lu, mo=%04lx]",
622 EXT2FS_VERSION
, EXT2FS_DATE
, sb
->s_blocksize
,
625 EXT2_BLOCKS_PER_GROUP(sb
),
626 EXT2_INODES_PER_GROUP(sb
),
631 static int ext2_check_descriptors(struct super_block
*sb
)
634 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
636 ext2_debug ("Checking group descriptors");
638 for (i
= 0; i
< sbi
->s_groups_count
; i
++) {
639 struct ext2_group_desc
*gdp
= ext2_get_group_desc(sb
, i
, NULL
);
640 ext2_fsblk_t first_block
= ext2_group_first_block_no(sb
, i
);
641 ext2_fsblk_t last_block
;
643 if (i
== sbi
->s_groups_count
- 1)
644 last_block
= le32_to_cpu(sbi
->s_es
->s_blocks_count
) - 1;
646 last_block
= first_block
+
647 (EXT2_BLOCKS_PER_GROUP(sb
) - 1);
649 if (le32_to_cpu(gdp
->bg_block_bitmap
) < first_block
||
650 le32_to_cpu(gdp
->bg_block_bitmap
) > last_block
)
652 ext2_error (sb
, "ext2_check_descriptors",
653 "Block bitmap for group %d"
654 " not in group (block %lu)!",
655 i
, (unsigned long) le32_to_cpu(gdp
->bg_block_bitmap
));
658 if (le32_to_cpu(gdp
->bg_inode_bitmap
) < first_block
||
659 le32_to_cpu(gdp
->bg_inode_bitmap
) > last_block
)
661 ext2_error (sb
, "ext2_check_descriptors",
662 "Inode bitmap for group %d"
663 " not in group (block %lu)!",
664 i
, (unsigned long) le32_to_cpu(gdp
->bg_inode_bitmap
));
667 if (le32_to_cpu(gdp
->bg_inode_table
) < first_block
||
668 le32_to_cpu(gdp
->bg_inode_table
) + sbi
->s_itb_per_group
- 1 >
671 ext2_error (sb
, "ext2_check_descriptors",
672 "Inode table for group %d"
673 " not in group (block %lu)!",
674 i
, (unsigned long) le32_to_cpu(gdp
->bg_inode_table
));
682 * Maximal file size. There is a direct, and {,double-,triple-}indirect
683 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
684 * We need to be 1 filesystem block less than the 2^32 sector limit.
686 static loff_t
ext2_max_size(int bits
)
688 loff_t res
= EXT2_NDIR_BLOCKS
;
692 /* This is calculated to be the largest file size for a
693 * dense, file such that the total number of
694 * sectors in the file, including data and all indirect blocks,
695 * does not exceed 2^32 -1
696 * __u32 i_blocks representing the total number of
697 * 512 bytes blocks of the file
699 upper_limit
= (1LL << 32) - 1;
701 /* total blocks in file system block size */
702 upper_limit
>>= (bits
- 9);
705 /* indirect blocks */
707 /* double indirect blocks */
708 meta_blocks
+= 1 + (1LL << (bits
-2));
709 /* tripple indirect blocks */
710 meta_blocks
+= 1 + (1LL << (bits
-2)) + (1LL << (2*(bits
-2)));
712 upper_limit
-= meta_blocks
;
713 upper_limit
<<= bits
;
715 res
+= 1LL << (bits
-2);
716 res
+= 1LL << (2*(bits
-2));
717 res
+= 1LL << (3*(bits
-2));
719 if (res
> upper_limit
)
722 if (res
> MAX_LFS_FILESIZE
)
723 res
= MAX_LFS_FILESIZE
;
728 static unsigned long descriptor_loc(struct super_block
*sb
,
729 unsigned long logic_sb_block
,
732 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
733 unsigned long bg
, first_meta_bg
;
736 first_meta_bg
= le32_to_cpu(sbi
->s_es
->s_first_meta_bg
);
738 if (!EXT2_HAS_INCOMPAT_FEATURE(sb
, EXT2_FEATURE_INCOMPAT_META_BG
) ||
740 return (logic_sb_block
+ nr
+ 1);
741 bg
= sbi
->s_desc_per_block
* nr
;
742 if (ext2_bg_has_super(sb
, bg
))
745 return ext2_group_first_block_no(sb
, bg
) + has_super
;
748 static int ext2_fill_super(struct super_block
*sb
, void *data
, int silent
)
750 struct buffer_head
* bh
;
751 struct ext2_sb_info
* sbi
;
752 struct ext2_super_block
* es
;
755 unsigned long sb_block
= get_sb_block(&data
);
756 unsigned long logic_sb_block
;
757 unsigned long offset
= 0;
758 unsigned long def_mount_opts
;
760 int blocksize
= BLOCK_SIZE
;
767 sbi
= kzalloc(sizeof(*sbi
), GFP_KERNEL
);
771 sbi
->s_blockgroup_lock
=
772 kzalloc(sizeof(struct blockgroup_lock
), GFP_KERNEL
);
773 if (!sbi
->s_blockgroup_lock
) {
778 sbi
->s_sb_block
= sb_block
;
780 spin_lock_init(&sbi
->s_lock
);
783 * See what the current blocksize for the device is, and
784 * use that as the blocksize. Otherwise (or if the blocksize
785 * is smaller than the default) use the default.
786 * This is important for devices that have a hardware
787 * sectorsize that is larger than the default.
789 blocksize
= sb_min_blocksize(sb
, BLOCK_SIZE
);
791 ext2_msg(sb
, KERN_ERR
, "error: unable to set blocksize");
796 * If the superblock doesn't start on a hardware sector boundary,
797 * calculate the offset.
799 if (blocksize
!= BLOCK_SIZE
) {
800 logic_sb_block
= (sb_block
*BLOCK_SIZE
) / blocksize
;
801 offset
= (sb_block
*BLOCK_SIZE
) % blocksize
;
803 logic_sb_block
= sb_block
;
806 if (!(bh
= sb_bread(sb
, logic_sb_block
))) {
807 ext2_msg(sb
, KERN_ERR
, "error: unable to read superblock");
811 * Note: s_es must be initialized as soon as possible because
812 * some ext2 macro-instructions depend on its value
814 es
= (struct ext2_super_block
*) (((char *)bh
->b_data
) + offset
);
816 sb
->s_magic
= le16_to_cpu(es
->s_magic
);
818 if (sb
->s_magic
!= EXT2_SUPER_MAGIC
)
821 /* Set defaults before we parse the mount options */
822 def_mount_opts
= le32_to_cpu(es
->s_default_mount_opts
);
823 if (def_mount_opts
& EXT2_DEFM_DEBUG
)
824 set_opt(sbi
->s_mount_opt
, DEBUG
);
825 if (def_mount_opts
& EXT2_DEFM_BSDGROUPS
)
826 set_opt(sbi
->s_mount_opt
, GRPID
);
827 if (def_mount_opts
& EXT2_DEFM_UID16
)
828 set_opt(sbi
->s_mount_opt
, NO_UID32
);
829 #ifdef CONFIG_EXT2_FS_XATTR
830 if (def_mount_opts
& EXT2_DEFM_XATTR_USER
)
831 set_opt(sbi
->s_mount_opt
, XATTR_USER
);
833 #ifdef CONFIG_EXT2_FS_POSIX_ACL
834 if (def_mount_opts
& EXT2_DEFM_ACL
)
835 set_opt(sbi
->s_mount_opt
, POSIX_ACL
);
838 if (le16_to_cpu(sbi
->s_es
->s_errors
) == EXT2_ERRORS_PANIC
)
839 set_opt(sbi
->s_mount_opt
, ERRORS_PANIC
);
840 else if (le16_to_cpu(sbi
->s_es
->s_errors
) == EXT2_ERRORS_CONTINUE
)
841 set_opt(sbi
->s_mount_opt
, ERRORS_CONT
);
843 set_opt(sbi
->s_mount_opt
, ERRORS_RO
);
845 sbi
->s_resuid
= le16_to_cpu(es
->s_def_resuid
);
846 sbi
->s_resgid
= le16_to_cpu(es
->s_def_resgid
);
848 set_opt(sbi
->s_mount_opt
, RESERVATION
);
850 if (!parse_options((char *) data
, sb
))
853 sb
->s_flags
= (sb
->s_flags
& ~MS_POSIXACL
) |
854 ((EXT2_SB(sb
)->s_mount_opt
& EXT2_MOUNT_POSIX_ACL
) ?
857 ext2_xip_verify_sb(sb
); /* see if bdev supports xip, unset
858 EXT2_MOUNT_XIP if not */
860 if (le32_to_cpu(es
->s_rev_level
) == EXT2_GOOD_OLD_REV
&&
861 (EXT2_HAS_COMPAT_FEATURE(sb
, ~0U) ||
862 EXT2_HAS_RO_COMPAT_FEATURE(sb
, ~0U) ||
863 EXT2_HAS_INCOMPAT_FEATURE(sb
, ~0U)))
864 ext2_msg(sb
, KERN_WARNING
,
865 "warning: feature flags set on rev 0 fs, "
866 "running e2fsck is recommended");
868 * Check feature flags regardless of the revision level, since we
869 * previously didn't change the revision level when setting the flags,
870 * so there is a chance incompat flags are set on a rev 0 filesystem.
872 features
= EXT2_HAS_INCOMPAT_FEATURE(sb
, ~EXT2_FEATURE_INCOMPAT_SUPP
);
874 ext2_msg(sb
, KERN_ERR
, "error: couldn't mount because of "
875 "unsupported optional features (%x)",
876 le32_to_cpu(features
));
879 if (!(sb
->s_flags
& MS_RDONLY
) &&
880 (features
= EXT2_HAS_RO_COMPAT_FEATURE(sb
, ~EXT2_FEATURE_RO_COMPAT_SUPP
))){
881 ext2_msg(sb
, KERN_ERR
, "error: couldn't mount RDWR because of "
882 "unsupported optional features (%x)",
883 le32_to_cpu(features
));
887 blocksize
= BLOCK_SIZE
<< le32_to_cpu(sbi
->s_es
->s_log_block_size
);
889 if (ext2_use_xip(sb
) && blocksize
!= PAGE_SIZE
) {
891 ext2_msg(sb
, KERN_ERR
,
892 "error: unsupported blocksize for xip");
896 /* If the blocksize doesn't match, re-read the thing.. */
897 if (sb
->s_blocksize
!= blocksize
) {
900 if (!sb_set_blocksize(sb
, blocksize
)) {
901 ext2_msg(sb
, KERN_ERR
, "error: blocksize is too small");
905 logic_sb_block
= (sb_block
*BLOCK_SIZE
) / blocksize
;
906 offset
= (sb_block
*BLOCK_SIZE
) % blocksize
;
907 bh
= sb_bread(sb
, logic_sb_block
);
909 ext2_msg(sb
, KERN_ERR
, "error: couldn't read"
910 "superblock on 2nd try");
913 es
= (struct ext2_super_block
*) (((char *)bh
->b_data
) + offset
);
915 if (es
->s_magic
!= cpu_to_le16(EXT2_SUPER_MAGIC
)) {
916 ext2_msg(sb
, KERN_ERR
, "error: magic mismatch");
921 sb
->s_maxbytes
= ext2_max_size(sb
->s_blocksize_bits
);
923 if (le32_to_cpu(es
->s_rev_level
) == EXT2_GOOD_OLD_REV
) {
924 sbi
->s_inode_size
= EXT2_GOOD_OLD_INODE_SIZE
;
925 sbi
->s_first_ino
= EXT2_GOOD_OLD_FIRST_INO
;
927 sbi
->s_inode_size
= le16_to_cpu(es
->s_inode_size
);
928 sbi
->s_first_ino
= le32_to_cpu(es
->s_first_ino
);
929 if ((sbi
->s_inode_size
< EXT2_GOOD_OLD_INODE_SIZE
) ||
930 !is_power_of_2(sbi
->s_inode_size
) ||
931 (sbi
->s_inode_size
> blocksize
)) {
932 ext2_msg(sb
, KERN_ERR
,
933 "error: unsupported inode size: %d",
939 sbi
->s_frag_size
= EXT2_MIN_FRAG_SIZE
<<
940 le32_to_cpu(es
->s_log_frag_size
);
941 if (sbi
->s_frag_size
== 0)
943 sbi
->s_frags_per_block
= sb
->s_blocksize
/ sbi
->s_frag_size
;
945 sbi
->s_blocks_per_group
= le32_to_cpu(es
->s_blocks_per_group
);
946 sbi
->s_frags_per_group
= le32_to_cpu(es
->s_frags_per_group
);
947 sbi
->s_inodes_per_group
= le32_to_cpu(es
->s_inodes_per_group
);
949 if (EXT2_INODE_SIZE(sb
) == 0)
951 sbi
->s_inodes_per_block
= sb
->s_blocksize
/ EXT2_INODE_SIZE(sb
);
952 if (sbi
->s_inodes_per_block
== 0 || sbi
->s_inodes_per_group
== 0)
954 sbi
->s_itb_per_group
= sbi
->s_inodes_per_group
/
955 sbi
->s_inodes_per_block
;
956 sbi
->s_desc_per_block
= sb
->s_blocksize
/
957 sizeof (struct ext2_group_desc
);
959 sbi
->s_mount_state
= le16_to_cpu(es
->s_state
);
960 sbi
->s_addr_per_block_bits
=
961 ilog2 (EXT2_ADDR_PER_BLOCK(sb
));
962 sbi
->s_desc_per_block_bits
=
963 ilog2 (EXT2_DESC_PER_BLOCK(sb
));
965 if (sb
->s_magic
!= EXT2_SUPER_MAGIC
)
968 if (sb
->s_blocksize
!= bh
->b_size
) {
970 ext2_msg(sb
, KERN_ERR
, "error: unsupported blocksize");
974 if (sb
->s_blocksize
!= sbi
->s_frag_size
) {
975 ext2_msg(sb
, KERN_ERR
,
976 "error: fragsize %lu != blocksize %lu"
977 "(not supported yet)",
978 sbi
->s_frag_size
, sb
->s_blocksize
);
982 if (sbi
->s_blocks_per_group
> sb
->s_blocksize
* 8) {
983 ext2_msg(sb
, KERN_ERR
,
984 "error: #blocks per group too big: %lu",
985 sbi
->s_blocks_per_group
);
988 if (sbi
->s_frags_per_group
> sb
->s_blocksize
* 8) {
989 ext2_msg(sb
, KERN_ERR
,
990 "error: #fragments per group too big: %lu",
991 sbi
->s_frags_per_group
);
994 if (sbi
->s_inodes_per_group
> sb
->s_blocksize
* 8) {
995 ext2_msg(sb
, KERN_ERR
,
996 "error: #inodes per group too big: %lu",
997 sbi
->s_inodes_per_group
);
1001 if (EXT2_BLOCKS_PER_GROUP(sb
) == 0)
1003 sbi
->s_groups_count
= ((le32_to_cpu(es
->s_blocks_count
) -
1004 le32_to_cpu(es
->s_first_data_block
) - 1)
1005 / EXT2_BLOCKS_PER_GROUP(sb
)) + 1;
1006 db_count
= (sbi
->s_groups_count
+ EXT2_DESC_PER_BLOCK(sb
) - 1) /
1007 EXT2_DESC_PER_BLOCK(sb
);
1008 sbi
->s_group_desc
= kmalloc (db_count
* sizeof (struct buffer_head
*), GFP_KERNEL
);
1009 if (sbi
->s_group_desc
== NULL
) {
1010 ext2_msg(sb
, KERN_ERR
, "error: not enough memory");
1013 bgl_lock_init(sbi
->s_blockgroup_lock
);
1014 sbi
->s_debts
= kcalloc(sbi
->s_groups_count
, sizeof(*sbi
->s_debts
), GFP_KERNEL
);
1015 if (!sbi
->s_debts
) {
1016 ext2_msg(sb
, KERN_ERR
, "error: not enough memory");
1017 goto failed_mount_group_desc
;
1019 for (i
= 0; i
< db_count
; i
++) {
1020 block
= descriptor_loc(sb
, logic_sb_block
, i
);
1021 sbi
->s_group_desc
[i
] = sb_bread(sb
, block
);
1022 if (!sbi
->s_group_desc
[i
]) {
1023 for (j
= 0; j
< i
; j
++)
1024 brelse (sbi
->s_group_desc
[j
]);
1025 ext2_msg(sb
, KERN_ERR
,
1026 "error: unable to read group descriptors");
1027 goto failed_mount_group_desc
;
1030 if (!ext2_check_descriptors (sb
)) {
1031 ext2_msg(sb
, KERN_ERR
, "group descriptors corrupted");
1034 sbi
->s_gdb_count
= db_count
;
1035 get_random_bytes(&sbi
->s_next_generation
, sizeof(u32
));
1036 spin_lock_init(&sbi
->s_next_gen_lock
);
1038 /* per fileystem reservation list head & lock */
1039 spin_lock_init(&sbi
->s_rsv_window_lock
);
1040 sbi
->s_rsv_window_root
= RB_ROOT
;
1042 * Add a single, static dummy reservation to the start of the
1043 * reservation window list --- it gives us a placeholder for
1044 * append-at-start-of-list which makes the allocation logic
1047 sbi
->s_rsv_window_head
.rsv_start
= EXT2_RESERVE_WINDOW_NOT_ALLOCATED
;
1048 sbi
->s_rsv_window_head
.rsv_end
= EXT2_RESERVE_WINDOW_NOT_ALLOCATED
;
1049 sbi
->s_rsv_window_head
.rsv_alloc_hit
= 0;
1050 sbi
->s_rsv_window_head
.rsv_goal_size
= 0;
1051 ext2_rsv_window_add(sb
, &sbi
->s_rsv_window_head
);
1053 err
= percpu_counter_init(&sbi
->s_freeblocks_counter
,
1054 ext2_count_free_blocks(sb
));
1056 err
= percpu_counter_init(&sbi
->s_freeinodes_counter
,
1057 ext2_count_free_inodes(sb
));
1060 err
= percpu_counter_init(&sbi
->s_dirs_counter
,
1061 ext2_count_dirs(sb
));
1064 ext2_msg(sb
, KERN_ERR
, "error: insufficient memory");
1068 * set up enough so that it can read an inode
1070 sb
->s_op
= &ext2_sops
;
1071 sb
->s_export_op
= &ext2_export_ops
;
1072 sb
->s_xattr
= ext2_xattr_handlers
;
1075 sb
->dq_op
= &dquot_operations
;
1076 sb
->s_qcop
= &dquot_quotactl_ops
;
1079 root
= ext2_iget(sb
, EXT2_ROOT_INO
);
1081 ret
= PTR_ERR(root
);
1084 if (!S_ISDIR(root
->i_mode
) || !root
->i_blocks
|| !root
->i_size
) {
1086 ext2_msg(sb
, KERN_ERR
, "error: corrupt root inode, run e2fsck");
1090 sb
->s_root
= d_alloc_root(root
);
1093 ext2_msg(sb
, KERN_ERR
, "error: get root inode failed");
1097 if (EXT2_HAS_COMPAT_FEATURE(sb
, EXT3_FEATURE_COMPAT_HAS_JOURNAL
))
1098 ext2_msg(sb
, KERN_WARNING
,
1099 "warning: mounting ext3 filesystem as ext2");
1100 if (ext2_setup_super (sb
, es
, sb
->s_flags
& MS_RDONLY
))
1101 sb
->s_flags
|= MS_RDONLY
;
1102 ext2_write_super(sb
);
1107 ext2_msg(sb
, KERN_ERR
,
1108 "error: can't find an ext2 filesystem on dev %s.",
1112 percpu_counter_destroy(&sbi
->s_freeblocks_counter
);
1113 percpu_counter_destroy(&sbi
->s_freeinodes_counter
);
1114 percpu_counter_destroy(&sbi
->s_dirs_counter
);
1116 for (i
= 0; i
< db_count
; i
++)
1117 brelse(sbi
->s_group_desc
[i
]);
1118 failed_mount_group_desc
:
1119 kfree(sbi
->s_group_desc
);
1120 kfree(sbi
->s_debts
);
1124 sb
->s_fs_info
= NULL
;
1125 kfree(sbi
->s_blockgroup_lock
);
1131 static void ext2_clear_super_error(struct super_block
*sb
)
1133 struct buffer_head
*sbh
= EXT2_SB(sb
)->s_sbh
;
1135 if (buffer_write_io_error(sbh
)) {
1137 * Oh, dear. A previous attempt to write the
1138 * superblock failed. This could happen because the
1139 * USB device was yanked out. Or it could happen to
1140 * be a transient write error and maybe the block will
1141 * be remapped. Nothing we can do but to retry the
1142 * write and hope for the best.
1144 ext2_msg(sb
, KERN_ERR
,
1145 "previous I/O error to superblock detected\n");
1146 clear_buffer_write_io_error(sbh
);
1147 set_buffer_uptodate(sbh
);
1151 static void ext2_sync_super(struct super_block
*sb
, struct ext2_super_block
*es
,
1154 ext2_clear_super_error(sb
);
1155 spin_lock(&EXT2_SB(sb
)->s_lock
);
1156 es
->s_free_blocks_count
= cpu_to_le32(ext2_count_free_blocks(sb
));
1157 es
->s_free_inodes_count
= cpu_to_le32(ext2_count_free_inodes(sb
));
1158 es
->s_wtime
= cpu_to_le32(get_seconds());
1159 /* unlock before we do IO */
1160 spin_unlock(&EXT2_SB(sb
)->s_lock
);
1161 mark_buffer_dirty(EXT2_SB(sb
)->s_sbh
);
1163 sync_dirty_buffer(EXT2_SB(sb
)->s_sbh
);
1168 * In the second extended file system, it is not necessary to
1169 * write the super block since we use a mapping of the
1170 * disk super block in a buffer.
1172 * However, this function is still used to set the fs valid
1173 * flags to 0. We need to set this flag to 0 since the fs
1174 * may have been checked while mounted and e2fsck may have
1175 * set s_state to EXT2_VALID_FS after some corrections.
1177 static int ext2_sync_fs(struct super_block
*sb
, int wait
)
1179 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
1180 struct ext2_super_block
*es
= EXT2_SB(sb
)->s_es
;
1182 spin_lock(&sbi
->s_lock
);
1183 if (es
->s_state
& cpu_to_le16(EXT2_VALID_FS
)) {
1184 ext2_debug("setting valid to 0\n");
1185 es
->s_state
&= cpu_to_le16(~EXT2_VALID_FS
);
1187 spin_unlock(&sbi
->s_lock
);
1188 ext2_sync_super(sb
, es
, wait
);
1193 void ext2_write_super(struct super_block
*sb
)
1195 if (!(sb
->s_flags
& MS_RDONLY
))
1196 ext2_sync_fs(sb
, 1);
1201 static int ext2_remount (struct super_block
* sb
, int * flags
, char * data
)
1203 struct ext2_sb_info
* sbi
= EXT2_SB(sb
);
1204 struct ext2_super_block
* es
;
1205 unsigned long old_mount_opt
= sbi
->s_mount_opt
;
1206 struct ext2_mount_options old_opts
;
1207 unsigned long old_sb_flags
;
1210 spin_lock(&sbi
->s_lock
);
1212 /* Store the old options */
1213 old_sb_flags
= sb
->s_flags
;
1214 old_opts
.s_mount_opt
= sbi
->s_mount_opt
;
1215 old_opts
.s_resuid
= sbi
->s_resuid
;
1216 old_opts
.s_resgid
= sbi
->s_resgid
;
1219 * Allow the "check" option to be passed as a remount option.
1221 if (!parse_options(data
, sb
)) {
1226 sb
->s_flags
= (sb
->s_flags
& ~MS_POSIXACL
) |
1227 ((sbi
->s_mount_opt
& EXT2_MOUNT_POSIX_ACL
) ? MS_POSIXACL
: 0);
1229 ext2_xip_verify_sb(sb
); /* see if bdev supports xip, unset
1230 EXT2_MOUNT_XIP if not */
1232 if ((ext2_use_xip(sb
)) && (sb
->s_blocksize
!= PAGE_SIZE
)) {
1233 ext2_msg(sb
, KERN_WARNING
,
1234 "warning: unsupported blocksize for xip");
1240 if ((sbi
->s_mount_opt
^ old_mount_opt
) & EXT2_MOUNT_XIP
) {
1241 ext2_msg(sb
, KERN_WARNING
, "warning: refusing change of "
1242 "xip flag with busy inodes while remounting");
1243 sbi
->s_mount_opt
&= ~EXT2_MOUNT_XIP
;
1244 sbi
->s_mount_opt
|= old_mount_opt
& EXT2_MOUNT_XIP
;
1246 if ((*flags
& MS_RDONLY
) == (sb
->s_flags
& MS_RDONLY
)) {
1247 spin_unlock(&sbi
->s_lock
);
1250 if (*flags
& MS_RDONLY
) {
1251 if (le16_to_cpu(es
->s_state
) & EXT2_VALID_FS
||
1252 !(sbi
->s_mount_state
& EXT2_VALID_FS
)) {
1253 spin_unlock(&sbi
->s_lock
);
1258 * OK, we are remounting a valid rw partition rdonly, so set
1259 * the rdonly flag and then mark the partition as valid again.
1261 es
->s_state
= cpu_to_le16(sbi
->s_mount_state
);
1262 es
->s_mtime
= cpu_to_le32(get_seconds());
1263 spin_unlock(&sbi
->s_lock
);
1265 err
= dquot_suspend(sb
, -1);
1267 spin_lock(&sbi
->s_lock
);
1271 ext2_sync_super(sb
, es
, 1);
1273 __le32 ret
= EXT2_HAS_RO_COMPAT_FEATURE(sb
,
1274 ~EXT2_FEATURE_RO_COMPAT_SUPP
);
1276 ext2_msg(sb
, KERN_WARNING
,
1277 "warning: couldn't remount RDWR because of "
1278 "unsupported optional features (%x).",
1284 * Mounting a RDONLY partition read-write, so reread and
1285 * store the current valid flag. (It may have been changed
1286 * by e2fsck since we originally mounted the partition.)
1288 sbi
->s_mount_state
= le16_to_cpu(es
->s_state
);
1289 if (!ext2_setup_super (sb
, es
, 0))
1290 sb
->s_flags
&= ~MS_RDONLY
;
1291 spin_unlock(&sbi
->s_lock
);
1293 ext2_write_super(sb
);
1295 dquot_resume(sb
, -1);
1300 sbi
->s_mount_opt
= old_opts
.s_mount_opt
;
1301 sbi
->s_resuid
= old_opts
.s_resuid
;
1302 sbi
->s_resgid
= old_opts
.s_resgid
;
1303 sb
->s_flags
= old_sb_flags
;
1304 spin_unlock(&sbi
->s_lock
);
1308 static int ext2_statfs (struct dentry
* dentry
, struct kstatfs
* buf
)
1310 struct super_block
*sb
= dentry
->d_sb
;
1311 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
1312 struct ext2_super_block
*es
= sbi
->s_es
;
1315 spin_lock(&sbi
->s_lock
);
1317 if (test_opt (sb
, MINIX_DF
))
1318 sbi
->s_overhead_last
= 0;
1319 else if (sbi
->s_blocks_last
!= le32_to_cpu(es
->s_blocks_count
)) {
1320 unsigned long i
, overhead
= 0;
1324 * Compute the overhead (FS structures). This is constant
1325 * for a given filesystem unless the number of block groups
1326 * changes so we cache the previous value until it does.
1330 * All of the blocks before first_data_block are
1333 overhead
= le32_to_cpu(es
->s_first_data_block
);
1336 * Add the overhead attributed to the superblock and
1337 * block group descriptors. If the sparse superblocks
1338 * feature is turned on, then not all groups have this.
1340 for (i
= 0; i
< sbi
->s_groups_count
; i
++)
1341 overhead
+= ext2_bg_has_super(sb
, i
) +
1342 ext2_bg_num_gdb(sb
, i
);
1345 * Every block group has an inode bitmap, a block
1346 * bitmap, and an inode table.
1348 overhead
+= (sbi
->s_groups_count
*
1349 (2 + sbi
->s_itb_per_group
));
1350 sbi
->s_overhead_last
= overhead
;
1352 sbi
->s_blocks_last
= le32_to_cpu(es
->s_blocks_count
);
1355 buf
->f_type
= EXT2_SUPER_MAGIC
;
1356 buf
->f_bsize
= sb
->s_blocksize
;
1357 buf
->f_blocks
= le32_to_cpu(es
->s_blocks_count
) - sbi
->s_overhead_last
;
1358 buf
->f_bfree
= ext2_count_free_blocks(sb
);
1359 es
->s_free_blocks_count
= cpu_to_le32(buf
->f_bfree
);
1360 buf
->f_bavail
= buf
->f_bfree
- le32_to_cpu(es
->s_r_blocks_count
);
1361 if (buf
->f_bfree
< le32_to_cpu(es
->s_r_blocks_count
))
1363 buf
->f_files
= le32_to_cpu(es
->s_inodes_count
);
1364 buf
->f_ffree
= ext2_count_free_inodes(sb
);
1365 es
->s_free_inodes_count
= cpu_to_le32(buf
->f_ffree
);
1366 buf
->f_namelen
= EXT2_NAME_LEN
;
1367 fsid
= le64_to_cpup((void *)es
->s_uuid
) ^
1368 le64_to_cpup((void *)es
->s_uuid
+ sizeof(u64
));
1369 buf
->f_fsid
.val
[0] = fsid
& 0xFFFFFFFFUL
;
1370 buf
->f_fsid
.val
[1] = (fsid
>> 32) & 0xFFFFFFFFUL
;
1371 spin_unlock(&sbi
->s_lock
);
1375 static struct dentry
*ext2_mount(struct file_system_type
*fs_type
,
1376 int flags
, const char *dev_name
, void *data
)
1378 return mount_bdev(fs_type
, flags
, dev_name
, data
, ext2_fill_super
);
1383 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1384 * acquiring the locks... As quota files are never truncated and quota code
1385 * itself serializes the operations (and no one else should touch the files)
1386 * we don't have to be afraid of races */
1387 static ssize_t
ext2_quota_read(struct super_block
*sb
, int type
, char *data
,
1388 size_t len
, loff_t off
)
1390 struct inode
*inode
= sb_dqopt(sb
)->files
[type
];
1391 sector_t blk
= off
>> EXT2_BLOCK_SIZE_BITS(sb
);
1393 int offset
= off
& (sb
->s_blocksize
- 1);
1396 struct buffer_head tmp_bh
;
1397 struct buffer_head
*bh
;
1398 loff_t i_size
= i_size_read(inode
);
1402 if (off
+len
> i_size
)
1405 while (toread
> 0) {
1406 tocopy
= sb
->s_blocksize
- offset
< toread
?
1407 sb
->s_blocksize
- offset
: toread
;
1410 tmp_bh
.b_size
= sb
->s_blocksize
;
1411 err
= ext2_get_block(inode
, blk
, &tmp_bh
, 0);
1414 if (!buffer_mapped(&tmp_bh
)) /* A hole? */
1415 memset(data
, 0, tocopy
);
1417 bh
= sb_bread(sb
, tmp_bh
.b_blocknr
);
1420 memcpy(data
, bh
->b_data
+offset
, tocopy
);
1431 /* Write to quotafile */
1432 static ssize_t
ext2_quota_write(struct super_block
*sb
, int type
,
1433 const char *data
, size_t len
, loff_t off
)
1435 struct inode
*inode
= sb_dqopt(sb
)->files
[type
];
1436 sector_t blk
= off
>> EXT2_BLOCK_SIZE_BITS(sb
);
1438 int offset
= off
& (sb
->s_blocksize
- 1);
1440 size_t towrite
= len
;
1441 struct buffer_head tmp_bh
;
1442 struct buffer_head
*bh
;
1444 mutex_lock_nested(&inode
->i_mutex
, I_MUTEX_QUOTA
);
1445 while (towrite
> 0) {
1446 tocopy
= sb
->s_blocksize
- offset
< towrite
?
1447 sb
->s_blocksize
- offset
: towrite
;
1450 err
= ext2_get_block(inode
, blk
, &tmp_bh
, 1);
1453 if (offset
|| tocopy
!= EXT2_BLOCK_SIZE(sb
))
1454 bh
= sb_bread(sb
, tmp_bh
.b_blocknr
);
1456 bh
= sb_getblk(sb
, tmp_bh
.b_blocknr
);
1462 memcpy(bh
->b_data
+offset
, data
, tocopy
);
1463 flush_dcache_page(bh
->b_page
);
1464 set_buffer_uptodate(bh
);
1465 mark_buffer_dirty(bh
);
1474 if (len
== towrite
) {
1475 mutex_unlock(&inode
->i_mutex
);
1478 if (inode
->i_size
< off
+len
-towrite
)
1479 i_size_write(inode
, off
+len
-towrite
);
1481 inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
1482 mark_inode_dirty(inode
);
1483 mutex_unlock(&inode
->i_mutex
);
1484 return len
- towrite
;
1489 static struct file_system_type ext2_fs_type
= {
1490 .owner
= THIS_MODULE
,
1492 .mount
= ext2_mount
,
1493 .kill_sb
= kill_block_super
,
1494 .fs_flags
= FS_REQUIRES_DEV
,
1497 static int __init
init_ext2_fs(void)
1499 int err
= init_ext2_xattr();
1502 err
= init_inodecache();
1505 err
= register_filesystem(&ext2_fs_type
);
1510 destroy_inodecache();
1516 static void __exit
exit_ext2_fs(void)
1518 unregister_filesystem(&ext2_fs_type
);
1519 destroy_inodecache();
1523 module_init(init_ext2_fs
)
1524 module_exit(exit_ext2_fs
)