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
);
133 ext2_xattr_put_super(sb
);
134 if (!(sb
->s_flags
& MS_RDONLY
)) {
135 struct ext2_super_block
*es
= sbi
->s_es
;
137 spin_lock(&sbi
->s_lock
);
138 es
->s_state
= cpu_to_le16(sbi
->s_mount_state
);
139 spin_unlock(&sbi
->s_lock
);
140 ext2_sync_super(sb
, es
, 1);
142 db_count
= sbi
->s_gdb_count
;
143 for (i
= 0; i
< db_count
; i
++)
144 if (sbi
->s_group_desc
[i
])
145 brelse (sbi
->s_group_desc
[i
]);
146 kfree(sbi
->s_group_desc
);
148 percpu_counter_destroy(&sbi
->s_freeblocks_counter
);
149 percpu_counter_destroy(&sbi
->s_freeinodes_counter
);
150 percpu_counter_destroy(&sbi
->s_dirs_counter
);
152 sb
->s_fs_info
= NULL
;
153 kfree(sbi
->s_blockgroup_lock
);
157 static struct kmem_cache
* ext2_inode_cachep
;
159 static struct inode
*ext2_alloc_inode(struct super_block
*sb
)
161 struct ext2_inode_info
*ei
;
162 ei
= (struct ext2_inode_info
*)kmem_cache_alloc(ext2_inode_cachep
, GFP_KERNEL
);
165 ei
->i_block_alloc_info
= NULL
;
166 ei
->vfs_inode
.i_version
= 1;
167 return &ei
->vfs_inode
;
170 static void ext2_i_callback(struct rcu_head
*head
)
172 struct inode
*inode
= container_of(head
, struct inode
, i_rcu
);
173 kmem_cache_free(ext2_inode_cachep
, EXT2_I(inode
));
176 static void ext2_destroy_inode(struct inode
*inode
)
178 call_rcu(&inode
->i_rcu
, ext2_i_callback
);
181 static void init_once(void *foo
)
183 struct ext2_inode_info
*ei
= (struct ext2_inode_info
*) foo
;
185 rwlock_init(&ei
->i_meta_lock
);
186 #ifdef CONFIG_EXT2_FS_XATTR
187 init_rwsem(&ei
->xattr_sem
);
189 mutex_init(&ei
->truncate_mutex
);
190 inode_init_once(&ei
->vfs_inode
);
193 static int init_inodecache(void)
195 ext2_inode_cachep
= kmem_cache_create("ext2_inode_cache",
196 sizeof(struct ext2_inode_info
),
197 0, (SLAB_RECLAIM_ACCOUNT
|
200 if (ext2_inode_cachep
== NULL
)
205 static void destroy_inodecache(void)
207 kmem_cache_destroy(ext2_inode_cachep
);
210 static int ext2_show_options(struct seq_file
*seq
, struct dentry
*root
)
212 struct super_block
*sb
= root
->d_sb
;
213 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
214 struct ext2_super_block
*es
= sbi
->s_es
;
215 unsigned long def_mount_opts
;
217 spin_lock(&sbi
->s_lock
);
218 def_mount_opts
= le32_to_cpu(es
->s_default_mount_opts
);
220 if (sbi
->s_sb_block
!= 1)
221 seq_printf(seq
, ",sb=%lu", sbi
->s_sb_block
);
222 if (test_opt(sb
, MINIX_DF
))
223 seq_puts(seq
, ",minixdf");
224 if (test_opt(sb
, GRPID
))
225 seq_puts(seq
, ",grpid");
226 if (!test_opt(sb
, GRPID
) && (def_mount_opts
& EXT2_DEFM_BSDGROUPS
))
227 seq_puts(seq
, ",nogrpid");
228 if (!uid_eq(sbi
->s_resuid
, make_kuid(&init_user_ns
, EXT2_DEF_RESUID
)) ||
229 le16_to_cpu(es
->s_def_resuid
) != EXT2_DEF_RESUID
) {
230 seq_printf(seq
, ",resuid=%u",
231 from_kuid_munged(&init_user_ns
, sbi
->s_resuid
));
233 if (!gid_eq(sbi
->s_resgid
, make_kgid(&init_user_ns
, EXT2_DEF_RESGID
)) ||
234 le16_to_cpu(es
->s_def_resgid
) != EXT2_DEF_RESGID
) {
235 seq_printf(seq
, ",resgid=%u",
236 from_kgid_munged(&init_user_ns
, sbi
->s_resgid
));
238 if (test_opt(sb
, ERRORS_RO
)) {
239 int def_errors
= le16_to_cpu(es
->s_errors
);
241 if (def_errors
== EXT2_ERRORS_PANIC
||
242 def_errors
== EXT2_ERRORS_CONTINUE
) {
243 seq_puts(seq
, ",errors=remount-ro");
246 if (test_opt(sb
, ERRORS_CONT
))
247 seq_puts(seq
, ",errors=continue");
248 if (test_opt(sb
, ERRORS_PANIC
))
249 seq_puts(seq
, ",errors=panic");
250 if (test_opt(sb
, NO_UID32
))
251 seq_puts(seq
, ",nouid32");
252 if (test_opt(sb
, DEBUG
))
253 seq_puts(seq
, ",debug");
254 if (test_opt(sb
, OLDALLOC
))
255 seq_puts(seq
, ",oldalloc");
257 #ifdef CONFIG_EXT2_FS_XATTR
258 if (test_opt(sb
, XATTR_USER
))
259 seq_puts(seq
, ",user_xattr");
260 if (!test_opt(sb
, XATTR_USER
) &&
261 (def_mount_opts
& EXT2_DEFM_XATTR_USER
)) {
262 seq_puts(seq
, ",nouser_xattr");
266 #ifdef CONFIG_EXT2_FS_POSIX_ACL
267 if (test_opt(sb
, POSIX_ACL
))
268 seq_puts(seq
, ",acl");
269 if (!test_opt(sb
, POSIX_ACL
) && (def_mount_opts
& EXT2_DEFM_ACL
))
270 seq_puts(seq
, ",noacl");
273 if (test_opt(sb
, NOBH
))
274 seq_puts(seq
, ",nobh");
276 #if defined(CONFIG_QUOTA)
277 if (sbi
->s_mount_opt
& EXT2_MOUNT_USRQUOTA
)
278 seq_puts(seq
, ",usrquota");
280 if (sbi
->s_mount_opt
& EXT2_MOUNT_GRPQUOTA
)
281 seq_puts(seq
, ",grpquota");
284 #if defined(CONFIG_EXT2_FS_XIP)
285 if (sbi
->s_mount_opt
& EXT2_MOUNT_XIP
)
286 seq_puts(seq
, ",xip");
289 if (!test_opt(sb
, RESERVATION
))
290 seq_puts(seq
, ",noreservation");
292 spin_unlock(&sbi
->s_lock
);
297 static ssize_t
ext2_quota_read(struct super_block
*sb
, int type
, char *data
, size_t len
, loff_t off
);
298 static ssize_t
ext2_quota_write(struct super_block
*sb
, int type
, const char *data
, size_t len
, loff_t off
);
301 static const struct super_operations ext2_sops
= {
302 .alloc_inode
= ext2_alloc_inode
,
303 .destroy_inode
= ext2_destroy_inode
,
304 .write_inode
= ext2_write_inode
,
305 .evict_inode
= ext2_evict_inode
,
306 .put_super
= ext2_put_super
,
307 .sync_fs
= ext2_sync_fs
,
308 .statfs
= ext2_statfs
,
309 .remount_fs
= ext2_remount
,
310 .show_options
= ext2_show_options
,
312 .quota_read
= ext2_quota_read
,
313 .quota_write
= ext2_quota_write
,
317 static struct inode
*ext2_nfs_get_inode(struct super_block
*sb
,
318 u64 ino
, u32 generation
)
322 if (ino
< EXT2_FIRST_INO(sb
) && ino
!= EXT2_ROOT_INO
)
323 return ERR_PTR(-ESTALE
);
324 if (ino
> le32_to_cpu(EXT2_SB(sb
)->s_es
->s_inodes_count
))
325 return ERR_PTR(-ESTALE
);
328 * ext2_iget isn't quite right if the inode is currently unallocated!
329 * However ext2_iget currently does appropriate checks to handle stale
330 * inodes so everything is OK.
332 inode
= ext2_iget(sb
, ino
);
334 return ERR_CAST(inode
);
335 if (generation
&& inode
->i_generation
!= generation
) {
336 /* we didn't find the right inode.. */
338 return ERR_PTR(-ESTALE
);
343 static struct dentry
*ext2_fh_to_dentry(struct super_block
*sb
, struct fid
*fid
,
344 int fh_len
, int fh_type
)
346 return generic_fh_to_dentry(sb
, fid
, fh_len
, fh_type
,
350 static struct dentry
*ext2_fh_to_parent(struct super_block
*sb
, struct fid
*fid
,
351 int fh_len
, int fh_type
)
353 return generic_fh_to_parent(sb
, fid
, fh_len
, fh_type
,
357 static const struct export_operations ext2_export_ops
= {
358 .fh_to_dentry
= ext2_fh_to_dentry
,
359 .fh_to_parent
= ext2_fh_to_parent
,
360 .get_parent
= ext2_get_parent
,
363 static unsigned long get_sb_block(void **data
)
365 unsigned long sb_block
;
366 char *options
= (char *) *data
;
368 if (!options
|| strncmp(options
, "sb=", 3) != 0)
369 return 1; /* Default location */
371 sb_block
= simple_strtoul(options
, &options
, 0);
372 if (*options
&& *options
!= ',') {
373 printk("EXT2-fs: Invalid sb specification: %s\n",
379 *data
= (void *) options
;
384 Opt_bsd_df
, Opt_minix_df
, Opt_grpid
, Opt_nogrpid
,
385 Opt_resgid
, Opt_resuid
, Opt_sb
, Opt_err_cont
, Opt_err_panic
,
386 Opt_err_ro
, Opt_nouid32
, Opt_nocheck
, Opt_debug
,
387 Opt_oldalloc
, Opt_orlov
, Opt_nobh
, Opt_user_xattr
, Opt_nouser_xattr
,
388 Opt_acl
, Opt_noacl
, Opt_xip
, Opt_ignore
, Opt_err
, Opt_quota
,
389 Opt_usrquota
, Opt_grpquota
, Opt_reservation
, Opt_noreservation
392 static const match_table_t tokens
= {
393 {Opt_bsd_df
, "bsddf"},
394 {Opt_minix_df
, "minixdf"},
395 {Opt_grpid
, "grpid"},
396 {Opt_grpid
, "bsdgroups"},
397 {Opt_nogrpid
, "nogrpid"},
398 {Opt_nogrpid
, "sysvgroups"},
399 {Opt_resgid
, "resgid=%u"},
400 {Opt_resuid
, "resuid=%u"},
402 {Opt_err_cont
, "errors=continue"},
403 {Opt_err_panic
, "errors=panic"},
404 {Opt_err_ro
, "errors=remount-ro"},
405 {Opt_nouid32
, "nouid32"},
406 {Opt_nocheck
, "check=none"},
407 {Opt_nocheck
, "nocheck"},
408 {Opt_debug
, "debug"},
409 {Opt_oldalloc
, "oldalloc"},
410 {Opt_orlov
, "orlov"},
412 {Opt_user_xattr
, "user_xattr"},
413 {Opt_nouser_xattr
, "nouser_xattr"},
415 {Opt_noacl
, "noacl"},
417 {Opt_grpquota
, "grpquota"},
418 {Opt_ignore
, "noquota"},
419 {Opt_quota
, "quota"},
420 {Opt_usrquota
, "usrquota"},
421 {Opt_reservation
, "reservation"},
422 {Opt_noreservation
, "noreservation"},
426 static int parse_options(char *options
, struct super_block
*sb
)
429 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
430 substring_t args
[MAX_OPT_ARGS
];
438 while ((p
= strsep (&options
, ",")) != NULL
) {
443 token
= match_token(p
, tokens
, args
);
446 clear_opt (sbi
->s_mount_opt
, MINIX_DF
);
449 set_opt (sbi
->s_mount_opt
, MINIX_DF
);
452 set_opt (sbi
->s_mount_opt
, GRPID
);
455 clear_opt (sbi
->s_mount_opt
, GRPID
);
458 if (match_int(&args
[0], &option
))
460 uid
= make_kuid(current_user_ns(), option
);
461 if (!uid_valid(uid
)) {
462 ext2_msg(sb
, KERN_ERR
, "Invalid uid value %d", option
);
469 if (match_int(&args
[0], &option
))
471 gid
= make_kgid(current_user_ns(), option
);
472 if (!gid_valid(gid
)) {
473 ext2_msg(sb
, KERN_ERR
, "Invalid gid value %d", option
);
479 /* handled by get_sb_block() instead of here */
480 /* *sb_block = match_int(&args[0]); */
483 clear_opt (sbi
->s_mount_opt
, ERRORS_CONT
);
484 clear_opt (sbi
->s_mount_opt
, ERRORS_RO
);
485 set_opt (sbi
->s_mount_opt
, ERRORS_PANIC
);
488 clear_opt (sbi
->s_mount_opt
, ERRORS_CONT
);
489 clear_opt (sbi
->s_mount_opt
, ERRORS_PANIC
);
490 set_opt (sbi
->s_mount_opt
, ERRORS_RO
);
493 clear_opt (sbi
->s_mount_opt
, ERRORS_RO
);
494 clear_opt (sbi
->s_mount_opt
, ERRORS_PANIC
);
495 set_opt (sbi
->s_mount_opt
, ERRORS_CONT
);
498 set_opt (sbi
->s_mount_opt
, NO_UID32
);
501 clear_opt (sbi
->s_mount_opt
, CHECK
);
504 set_opt (sbi
->s_mount_opt
, DEBUG
);
507 set_opt (sbi
->s_mount_opt
, OLDALLOC
);
510 clear_opt (sbi
->s_mount_opt
, OLDALLOC
);
513 set_opt (sbi
->s_mount_opt
, NOBH
);
515 #ifdef CONFIG_EXT2_FS_XATTR
517 set_opt (sbi
->s_mount_opt
, XATTR_USER
);
519 case Opt_nouser_xattr
:
520 clear_opt (sbi
->s_mount_opt
, XATTR_USER
);
524 case Opt_nouser_xattr
:
525 ext2_msg(sb
, KERN_INFO
, "(no)user_xattr options"
529 #ifdef CONFIG_EXT2_FS_POSIX_ACL
531 set_opt(sbi
->s_mount_opt
, POSIX_ACL
);
534 clear_opt(sbi
->s_mount_opt
, POSIX_ACL
);
539 ext2_msg(sb
, KERN_INFO
,
540 "(no)acl options not supported");
544 #ifdef CONFIG_EXT2_FS_XIP
545 set_opt (sbi
->s_mount_opt
, XIP
);
547 ext2_msg(sb
, KERN_INFO
, "xip option not supported");
551 #if defined(CONFIG_QUOTA)
554 set_opt(sbi
->s_mount_opt
, USRQUOTA
);
558 set_opt(sbi
->s_mount_opt
, GRPQUOTA
);
564 ext2_msg(sb
, KERN_INFO
,
565 "quota operations not supported");
569 case Opt_reservation
:
570 set_opt(sbi
->s_mount_opt
, RESERVATION
);
571 ext2_msg(sb
, KERN_INFO
, "reservations ON");
573 case Opt_noreservation
:
574 clear_opt(sbi
->s_mount_opt
, RESERVATION
);
575 ext2_msg(sb
, KERN_INFO
, "reservations OFF");
586 static int ext2_setup_super (struct super_block
* sb
,
587 struct ext2_super_block
* es
,
591 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
593 if (le32_to_cpu(es
->s_rev_level
) > EXT2_MAX_SUPP_REV
) {
594 ext2_msg(sb
, KERN_ERR
,
595 "error: revision level too high, "
596 "forcing read-only mode");
601 if (!(sbi
->s_mount_state
& EXT2_VALID_FS
))
602 ext2_msg(sb
, KERN_WARNING
,
603 "warning: mounting unchecked fs, "
604 "running e2fsck is recommended");
605 else if ((sbi
->s_mount_state
& EXT2_ERROR_FS
))
606 ext2_msg(sb
, KERN_WARNING
,
607 "warning: mounting fs with errors, "
608 "running e2fsck is recommended");
609 else if ((__s16
) le16_to_cpu(es
->s_max_mnt_count
) >= 0 &&
610 le16_to_cpu(es
->s_mnt_count
) >=
611 (unsigned short) (__s16
) le16_to_cpu(es
->s_max_mnt_count
))
612 ext2_msg(sb
, KERN_WARNING
,
613 "warning: maximal mount count reached, "
614 "running e2fsck is recommended");
615 else if (le32_to_cpu(es
->s_checkinterval
) &&
616 (le32_to_cpu(es
->s_lastcheck
) +
617 le32_to_cpu(es
->s_checkinterval
) <= get_seconds()))
618 ext2_msg(sb
, KERN_WARNING
,
619 "warning: checktime reached, "
620 "running e2fsck is recommended");
621 if (!le16_to_cpu(es
->s_max_mnt_count
))
622 es
->s_max_mnt_count
= cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT
);
623 le16_add_cpu(&es
->s_mnt_count
, 1);
624 if (test_opt (sb
, DEBUG
))
625 ext2_msg(sb
, KERN_INFO
, "%s, %s, bs=%lu, fs=%lu, gc=%lu, "
626 "bpg=%lu, ipg=%lu, mo=%04lx]",
627 EXT2FS_VERSION
, EXT2FS_DATE
, sb
->s_blocksize
,
630 EXT2_BLOCKS_PER_GROUP(sb
),
631 EXT2_INODES_PER_GROUP(sb
),
636 static int ext2_check_descriptors(struct super_block
*sb
)
639 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
641 ext2_debug ("Checking group descriptors");
643 for (i
= 0; i
< sbi
->s_groups_count
; i
++) {
644 struct ext2_group_desc
*gdp
= ext2_get_group_desc(sb
, i
, NULL
);
645 ext2_fsblk_t first_block
= ext2_group_first_block_no(sb
, i
);
646 ext2_fsblk_t last_block
;
648 if (i
== sbi
->s_groups_count
- 1)
649 last_block
= le32_to_cpu(sbi
->s_es
->s_blocks_count
) - 1;
651 last_block
= first_block
+
652 (EXT2_BLOCKS_PER_GROUP(sb
) - 1);
654 if (le32_to_cpu(gdp
->bg_block_bitmap
) < first_block
||
655 le32_to_cpu(gdp
->bg_block_bitmap
) > last_block
)
657 ext2_error (sb
, "ext2_check_descriptors",
658 "Block bitmap for group %d"
659 " not in group (block %lu)!",
660 i
, (unsigned long) le32_to_cpu(gdp
->bg_block_bitmap
));
663 if (le32_to_cpu(gdp
->bg_inode_bitmap
) < first_block
||
664 le32_to_cpu(gdp
->bg_inode_bitmap
) > last_block
)
666 ext2_error (sb
, "ext2_check_descriptors",
667 "Inode bitmap for group %d"
668 " not in group (block %lu)!",
669 i
, (unsigned long) le32_to_cpu(gdp
->bg_inode_bitmap
));
672 if (le32_to_cpu(gdp
->bg_inode_table
) < first_block
||
673 le32_to_cpu(gdp
->bg_inode_table
) + sbi
->s_itb_per_group
- 1 >
676 ext2_error (sb
, "ext2_check_descriptors",
677 "Inode table for group %d"
678 " not in group (block %lu)!",
679 i
, (unsigned long) le32_to_cpu(gdp
->bg_inode_table
));
687 * Maximal file size. There is a direct, and {,double-,triple-}indirect
688 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
689 * We need to be 1 filesystem block less than the 2^32 sector limit.
691 static loff_t
ext2_max_size(int bits
)
693 loff_t res
= EXT2_NDIR_BLOCKS
;
697 /* This is calculated to be the largest file size for a
698 * dense, file such that the total number of
699 * sectors in the file, including data and all indirect blocks,
700 * does not exceed 2^32 -1
701 * __u32 i_blocks representing the total number of
702 * 512 bytes blocks of the file
704 upper_limit
= (1LL << 32) - 1;
706 /* total blocks in file system block size */
707 upper_limit
>>= (bits
- 9);
710 /* indirect blocks */
712 /* double indirect blocks */
713 meta_blocks
+= 1 + (1LL << (bits
-2));
714 /* tripple indirect blocks */
715 meta_blocks
+= 1 + (1LL << (bits
-2)) + (1LL << (2*(bits
-2)));
717 upper_limit
-= meta_blocks
;
718 upper_limit
<<= bits
;
720 res
+= 1LL << (bits
-2);
721 res
+= 1LL << (2*(bits
-2));
722 res
+= 1LL << (3*(bits
-2));
724 if (res
> upper_limit
)
727 if (res
> MAX_LFS_FILESIZE
)
728 res
= MAX_LFS_FILESIZE
;
733 static unsigned long descriptor_loc(struct super_block
*sb
,
734 unsigned long logic_sb_block
,
737 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
738 unsigned long bg
, first_meta_bg
;
741 first_meta_bg
= le32_to_cpu(sbi
->s_es
->s_first_meta_bg
);
743 if (!EXT2_HAS_INCOMPAT_FEATURE(sb
, EXT2_FEATURE_INCOMPAT_META_BG
) ||
745 return (logic_sb_block
+ nr
+ 1);
746 bg
= sbi
->s_desc_per_block
* nr
;
747 if (ext2_bg_has_super(sb
, bg
))
750 return ext2_group_first_block_no(sb
, bg
) + has_super
;
753 static int ext2_fill_super(struct super_block
*sb
, void *data
, int silent
)
755 struct buffer_head
* bh
;
756 struct ext2_sb_info
* sbi
;
757 struct ext2_super_block
* es
;
760 unsigned long sb_block
= get_sb_block(&data
);
761 unsigned long logic_sb_block
;
762 unsigned long offset
= 0;
763 unsigned long def_mount_opts
;
765 int blocksize
= BLOCK_SIZE
;
772 sbi
= kzalloc(sizeof(*sbi
), GFP_KERNEL
);
776 sbi
->s_blockgroup_lock
=
777 kzalloc(sizeof(struct blockgroup_lock
), GFP_KERNEL
);
778 if (!sbi
->s_blockgroup_lock
) {
783 sbi
->s_sb_block
= sb_block
;
785 spin_lock_init(&sbi
->s_lock
);
788 * See what the current blocksize for the device is, and
789 * use that as the blocksize. Otherwise (or if the blocksize
790 * is smaller than the default) use the default.
791 * This is important for devices that have a hardware
792 * sectorsize that is larger than the default.
794 blocksize
= sb_min_blocksize(sb
, BLOCK_SIZE
);
796 ext2_msg(sb
, KERN_ERR
, "error: unable to set blocksize");
801 * If the superblock doesn't start on a hardware sector boundary,
802 * calculate the offset.
804 if (blocksize
!= BLOCK_SIZE
) {
805 logic_sb_block
= (sb_block
*BLOCK_SIZE
) / blocksize
;
806 offset
= (sb_block
*BLOCK_SIZE
) % blocksize
;
808 logic_sb_block
= sb_block
;
811 if (!(bh
= sb_bread(sb
, logic_sb_block
))) {
812 ext2_msg(sb
, KERN_ERR
, "error: unable to read superblock");
816 * Note: s_es must be initialized as soon as possible because
817 * some ext2 macro-instructions depend on its value
819 es
= (struct ext2_super_block
*) (((char *)bh
->b_data
) + offset
);
821 sb
->s_magic
= le16_to_cpu(es
->s_magic
);
823 if (sb
->s_magic
!= EXT2_SUPER_MAGIC
)
826 /* Set defaults before we parse the mount options */
827 def_mount_opts
= le32_to_cpu(es
->s_default_mount_opts
);
828 if (def_mount_opts
& EXT2_DEFM_DEBUG
)
829 set_opt(sbi
->s_mount_opt
, DEBUG
);
830 if (def_mount_opts
& EXT2_DEFM_BSDGROUPS
)
831 set_opt(sbi
->s_mount_opt
, GRPID
);
832 if (def_mount_opts
& EXT2_DEFM_UID16
)
833 set_opt(sbi
->s_mount_opt
, NO_UID32
);
834 #ifdef CONFIG_EXT2_FS_XATTR
835 if (def_mount_opts
& EXT2_DEFM_XATTR_USER
)
836 set_opt(sbi
->s_mount_opt
, XATTR_USER
);
838 #ifdef CONFIG_EXT2_FS_POSIX_ACL
839 if (def_mount_opts
& EXT2_DEFM_ACL
)
840 set_opt(sbi
->s_mount_opt
, POSIX_ACL
);
843 if (le16_to_cpu(sbi
->s_es
->s_errors
) == EXT2_ERRORS_PANIC
)
844 set_opt(sbi
->s_mount_opt
, ERRORS_PANIC
);
845 else if (le16_to_cpu(sbi
->s_es
->s_errors
) == EXT2_ERRORS_CONTINUE
)
846 set_opt(sbi
->s_mount_opt
, ERRORS_CONT
);
848 set_opt(sbi
->s_mount_opt
, ERRORS_RO
);
850 sbi
->s_resuid
= make_kuid(&init_user_ns
, le16_to_cpu(es
->s_def_resuid
));
851 sbi
->s_resgid
= make_kgid(&init_user_ns
, le16_to_cpu(es
->s_def_resgid
));
853 set_opt(sbi
->s_mount_opt
, RESERVATION
);
855 if (!parse_options((char *) data
, sb
))
858 sb
->s_flags
= (sb
->s_flags
& ~MS_POSIXACL
) |
859 ((EXT2_SB(sb
)->s_mount_opt
& EXT2_MOUNT_POSIX_ACL
) ?
862 ext2_xip_verify_sb(sb
); /* see if bdev supports xip, unset
863 EXT2_MOUNT_XIP if not */
865 if (le32_to_cpu(es
->s_rev_level
) == EXT2_GOOD_OLD_REV
&&
866 (EXT2_HAS_COMPAT_FEATURE(sb
, ~0U) ||
867 EXT2_HAS_RO_COMPAT_FEATURE(sb
, ~0U) ||
868 EXT2_HAS_INCOMPAT_FEATURE(sb
, ~0U)))
869 ext2_msg(sb
, KERN_WARNING
,
870 "warning: feature flags set on rev 0 fs, "
871 "running e2fsck is recommended");
873 * Check feature flags regardless of the revision level, since we
874 * previously didn't change the revision level when setting the flags,
875 * so there is a chance incompat flags are set on a rev 0 filesystem.
877 features
= EXT2_HAS_INCOMPAT_FEATURE(sb
, ~EXT2_FEATURE_INCOMPAT_SUPP
);
879 ext2_msg(sb
, KERN_ERR
, "error: couldn't mount because of "
880 "unsupported optional features (%x)",
881 le32_to_cpu(features
));
884 if (!(sb
->s_flags
& MS_RDONLY
) &&
885 (features
= EXT2_HAS_RO_COMPAT_FEATURE(sb
, ~EXT2_FEATURE_RO_COMPAT_SUPP
))){
886 ext2_msg(sb
, KERN_ERR
, "error: couldn't mount RDWR because of "
887 "unsupported optional features (%x)",
888 le32_to_cpu(features
));
892 blocksize
= BLOCK_SIZE
<< le32_to_cpu(sbi
->s_es
->s_log_block_size
);
894 if (ext2_use_xip(sb
) && blocksize
!= PAGE_SIZE
) {
896 ext2_msg(sb
, KERN_ERR
,
897 "error: unsupported blocksize for xip");
901 /* If the blocksize doesn't match, re-read the thing.. */
902 if (sb
->s_blocksize
!= blocksize
) {
905 if (!sb_set_blocksize(sb
, blocksize
)) {
906 ext2_msg(sb
, KERN_ERR
,
907 "error: bad blocksize %d", blocksize
);
911 logic_sb_block
= (sb_block
*BLOCK_SIZE
) / blocksize
;
912 offset
= (sb_block
*BLOCK_SIZE
) % blocksize
;
913 bh
= sb_bread(sb
, logic_sb_block
);
915 ext2_msg(sb
, KERN_ERR
, "error: couldn't read"
916 "superblock on 2nd try");
919 es
= (struct ext2_super_block
*) (((char *)bh
->b_data
) + offset
);
921 if (es
->s_magic
!= cpu_to_le16(EXT2_SUPER_MAGIC
)) {
922 ext2_msg(sb
, KERN_ERR
, "error: magic mismatch");
927 sb
->s_maxbytes
= ext2_max_size(sb
->s_blocksize_bits
);
928 sb
->s_max_links
= EXT2_LINK_MAX
;
930 if (le32_to_cpu(es
->s_rev_level
) == EXT2_GOOD_OLD_REV
) {
931 sbi
->s_inode_size
= EXT2_GOOD_OLD_INODE_SIZE
;
932 sbi
->s_first_ino
= EXT2_GOOD_OLD_FIRST_INO
;
934 sbi
->s_inode_size
= le16_to_cpu(es
->s_inode_size
);
935 sbi
->s_first_ino
= le32_to_cpu(es
->s_first_ino
);
936 if ((sbi
->s_inode_size
< EXT2_GOOD_OLD_INODE_SIZE
) ||
937 !is_power_of_2(sbi
->s_inode_size
) ||
938 (sbi
->s_inode_size
> blocksize
)) {
939 ext2_msg(sb
, KERN_ERR
,
940 "error: unsupported inode size: %d",
946 sbi
->s_frag_size
= EXT2_MIN_FRAG_SIZE
<<
947 le32_to_cpu(es
->s_log_frag_size
);
948 if (sbi
->s_frag_size
== 0)
950 sbi
->s_frags_per_block
= sb
->s_blocksize
/ sbi
->s_frag_size
;
952 sbi
->s_blocks_per_group
= le32_to_cpu(es
->s_blocks_per_group
);
953 sbi
->s_frags_per_group
= le32_to_cpu(es
->s_frags_per_group
);
954 sbi
->s_inodes_per_group
= le32_to_cpu(es
->s_inodes_per_group
);
956 if (EXT2_INODE_SIZE(sb
) == 0)
958 sbi
->s_inodes_per_block
= sb
->s_blocksize
/ EXT2_INODE_SIZE(sb
);
959 if (sbi
->s_inodes_per_block
== 0 || sbi
->s_inodes_per_group
== 0)
961 sbi
->s_itb_per_group
= sbi
->s_inodes_per_group
/
962 sbi
->s_inodes_per_block
;
963 sbi
->s_desc_per_block
= sb
->s_blocksize
/
964 sizeof (struct ext2_group_desc
);
966 sbi
->s_mount_state
= le16_to_cpu(es
->s_state
);
967 sbi
->s_addr_per_block_bits
=
968 ilog2 (EXT2_ADDR_PER_BLOCK(sb
));
969 sbi
->s_desc_per_block_bits
=
970 ilog2 (EXT2_DESC_PER_BLOCK(sb
));
972 if (sb
->s_magic
!= EXT2_SUPER_MAGIC
)
975 if (sb
->s_blocksize
!= bh
->b_size
) {
977 ext2_msg(sb
, KERN_ERR
, "error: unsupported blocksize");
981 if (sb
->s_blocksize
!= sbi
->s_frag_size
) {
982 ext2_msg(sb
, KERN_ERR
,
983 "error: fragsize %lu != blocksize %lu"
984 "(not supported yet)",
985 sbi
->s_frag_size
, sb
->s_blocksize
);
989 if (sbi
->s_blocks_per_group
> sb
->s_blocksize
* 8) {
990 ext2_msg(sb
, KERN_ERR
,
991 "error: #blocks per group too big: %lu",
992 sbi
->s_blocks_per_group
);
995 if (sbi
->s_frags_per_group
> sb
->s_blocksize
* 8) {
996 ext2_msg(sb
, KERN_ERR
,
997 "error: #fragments per group too big: %lu",
998 sbi
->s_frags_per_group
);
1001 if (sbi
->s_inodes_per_group
> sb
->s_blocksize
* 8) {
1002 ext2_msg(sb
, KERN_ERR
,
1003 "error: #inodes per group too big: %lu",
1004 sbi
->s_inodes_per_group
);
1008 if (EXT2_BLOCKS_PER_GROUP(sb
) == 0)
1010 sbi
->s_groups_count
= ((le32_to_cpu(es
->s_blocks_count
) -
1011 le32_to_cpu(es
->s_first_data_block
) - 1)
1012 / EXT2_BLOCKS_PER_GROUP(sb
)) + 1;
1013 db_count
= (sbi
->s_groups_count
+ EXT2_DESC_PER_BLOCK(sb
) - 1) /
1014 EXT2_DESC_PER_BLOCK(sb
);
1015 sbi
->s_group_desc
= kmalloc (db_count
* sizeof (struct buffer_head
*), GFP_KERNEL
);
1016 if (sbi
->s_group_desc
== NULL
) {
1017 ext2_msg(sb
, KERN_ERR
, "error: not enough memory");
1020 bgl_lock_init(sbi
->s_blockgroup_lock
);
1021 sbi
->s_debts
= kcalloc(sbi
->s_groups_count
, sizeof(*sbi
->s_debts
), GFP_KERNEL
);
1022 if (!sbi
->s_debts
) {
1023 ext2_msg(sb
, KERN_ERR
, "error: not enough memory");
1024 goto failed_mount_group_desc
;
1026 for (i
= 0; i
< db_count
; i
++) {
1027 block
= descriptor_loc(sb
, logic_sb_block
, i
);
1028 sbi
->s_group_desc
[i
] = sb_bread(sb
, block
);
1029 if (!sbi
->s_group_desc
[i
]) {
1030 for (j
= 0; j
< i
; j
++)
1031 brelse (sbi
->s_group_desc
[j
]);
1032 ext2_msg(sb
, KERN_ERR
,
1033 "error: unable to read group descriptors");
1034 goto failed_mount_group_desc
;
1037 if (!ext2_check_descriptors (sb
)) {
1038 ext2_msg(sb
, KERN_ERR
, "group descriptors corrupted");
1041 sbi
->s_gdb_count
= db_count
;
1042 get_random_bytes(&sbi
->s_next_generation
, sizeof(u32
));
1043 spin_lock_init(&sbi
->s_next_gen_lock
);
1045 /* per fileystem reservation list head & lock */
1046 spin_lock_init(&sbi
->s_rsv_window_lock
);
1047 sbi
->s_rsv_window_root
= RB_ROOT
;
1049 * Add a single, static dummy reservation to the start of the
1050 * reservation window list --- it gives us a placeholder for
1051 * append-at-start-of-list which makes the allocation logic
1054 sbi
->s_rsv_window_head
.rsv_start
= EXT2_RESERVE_WINDOW_NOT_ALLOCATED
;
1055 sbi
->s_rsv_window_head
.rsv_end
= EXT2_RESERVE_WINDOW_NOT_ALLOCATED
;
1056 sbi
->s_rsv_window_head
.rsv_alloc_hit
= 0;
1057 sbi
->s_rsv_window_head
.rsv_goal_size
= 0;
1058 ext2_rsv_window_add(sb
, &sbi
->s_rsv_window_head
);
1060 err
= percpu_counter_init(&sbi
->s_freeblocks_counter
,
1061 ext2_count_free_blocks(sb
));
1063 err
= percpu_counter_init(&sbi
->s_freeinodes_counter
,
1064 ext2_count_free_inodes(sb
));
1067 err
= percpu_counter_init(&sbi
->s_dirs_counter
,
1068 ext2_count_dirs(sb
));
1071 ext2_msg(sb
, KERN_ERR
, "error: insufficient memory");
1075 * set up enough so that it can read an inode
1077 sb
->s_op
= &ext2_sops
;
1078 sb
->s_export_op
= &ext2_export_ops
;
1079 sb
->s_xattr
= ext2_xattr_handlers
;
1082 sb
->dq_op
= &dquot_operations
;
1083 sb
->s_qcop
= &dquot_quotactl_ops
;
1086 root
= ext2_iget(sb
, EXT2_ROOT_INO
);
1088 ret
= PTR_ERR(root
);
1091 if (!S_ISDIR(root
->i_mode
) || !root
->i_blocks
|| !root
->i_size
) {
1093 ext2_msg(sb
, KERN_ERR
, "error: corrupt root inode, run e2fsck");
1097 sb
->s_root
= d_make_root(root
);
1099 ext2_msg(sb
, KERN_ERR
, "error: get root inode failed");
1103 if (EXT2_HAS_COMPAT_FEATURE(sb
, EXT3_FEATURE_COMPAT_HAS_JOURNAL
))
1104 ext2_msg(sb
, KERN_WARNING
,
1105 "warning: mounting ext3 filesystem as ext2");
1106 if (ext2_setup_super (sb
, es
, sb
->s_flags
& MS_RDONLY
))
1107 sb
->s_flags
|= MS_RDONLY
;
1108 ext2_write_super(sb
);
1113 ext2_msg(sb
, KERN_ERR
,
1114 "error: can't find an ext2 filesystem on dev %s.",
1118 percpu_counter_destroy(&sbi
->s_freeblocks_counter
);
1119 percpu_counter_destroy(&sbi
->s_freeinodes_counter
);
1120 percpu_counter_destroy(&sbi
->s_dirs_counter
);
1122 for (i
= 0; i
< db_count
; i
++)
1123 brelse(sbi
->s_group_desc
[i
]);
1124 failed_mount_group_desc
:
1125 kfree(sbi
->s_group_desc
);
1126 kfree(sbi
->s_debts
);
1130 sb
->s_fs_info
= NULL
;
1131 kfree(sbi
->s_blockgroup_lock
);
1137 static void ext2_clear_super_error(struct super_block
*sb
)
1139 struct buffer_head
*sbh
= EXT2_SB(sb
)->s_sbh
;
1141 if (buffer_write_io_error(sbh
)) {
1143 * Oh, dear. A previous attempt to write the
1144 * superblock failed. This could happen because the
1145 * USB device was yanked out. Or it could happen to
1146 * be a transient write error and maybe the block will
1147 * be remapped. Nothing we can do but to retry the
1148 * write and hope for the best.
1150 ext2_msg(sb
, KERN_ERR
,
1151 "previous I/O error to superblock detected\n");
1152 clear_buffer_write_io_error(sbh
);
1153 set_buffer_uptodate(sbh
);
1157 static void ext2_sync_super(struct super_block
*sb
, struct ext2_super_block
*es
,
1160 ext2_clear_super_error(sb
);
1161 spin_lock(&EXT2_SB(sb
)->s_lock
);
1162 es
->s_free_blocks_count
= cpu_to_le32(ext2_count_free_blocks(sb
));
1163 es
->s_free_inodes_count
= cpu_to_le32(ext2_count_free_inodes(sb
));
1164 es
->s_wtime
= cpu_to_le32(get_seconds());
1165 /* unlock before we do IO */
1166 spin_unlock(&EXT2_SB(sb
)->s_lock
);
1167 mark_buffer_dirty(EXT2_SB(sb
)->s_sbh
);
1169 sync_dirty_buffer(EXT2_SB(sb
)->s_sbh
);
1173 * In the second extended file system, it is not necessary to
1174 * write the super block since we use a mapping of the
1175 * disk super block in a buffer.
1177 * However, this function is still used to set the fs valid
1178 * flags to 0. We need to set this flag to 0 since the fs
1179 * may have been checked while mounted and e2fsck may have
1180 * set s_state to EXT2_VALID_FS after some corrections.
1182 static int ext2_sync_fs(struct super_block
*sb
, int wait
)
1184 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
1185 struct ext2_super_block
*es
= EXT2_SB(sb
)->s_es
;
1188 * Write quota structures to quota file, sync_blockdev() will write
1189 * them to disk later
1191 dquot_writeback_dquots(sb
, -1);
1193 spin_lock(&sbi
->s_lock
);
1194 if (es
->s_state
& cpu_to_le16(EXT2_VALID_FS
)) {
1195 ext2_debug("setting valid to 0\n");
1196 es
->s_state
&= cpu_to_le16(~EXT2_VALID_FS
);
1198 spin_unlock(&sbi
->s_lock
);
1199 ext2_sync_super(sb
, es
, wait
);
1204 void ext2_write_super(struct super_block
*sb
)
1206 if (!(sb
->s_flags
& MS_RDONLY
))
1207 ext2_sync_fs(sb
, 1);
1210 static int ext2_remount (struct super_block
* sb
, int * flags
, char * data
)
1212 struct ext2_sb_info
* sbi
= EXT2_SB(sb
);
1213 struct ext2_super_block
* es
;
1214 unsigned long old_mount_opt
= sbi
->s_mount_opt
;
1215 struct ext2_mount_options old_opts
;
1216 unsigned long old_sb_flags
;
1219 spin_lock(&sbi
->s_lock
);
1221 /* Store the old options */
1222 old_sb_flags
= sb
->s_flags
;
1223 old_opts
.s_mount_opt
= sbi
->s_mount_opt
;
1224 old_opts
.s_resuid
= sbi
->s_resuid
;
1225 old_opts
.s_resgid
= sbi
->s_resgid
;
1228 * Allow the "check" option to be passed as a remount option.
1230 if (!parse_options(data
, sb
)) {
1235 sb
->s_flags
= (sb
->s_flags
& ~MS_POSIXACL
) |
1236 ((sbi
->s_mount_opt
& EXT2_MOUNT_POSIX_ACL
) ? MS_POSIXACL
: 0);
1238 ext2_xip_verify_sb(sb
); /* see if bdev supports xip, unset
1239 EXT2_MOUNT_XIP if not */
1241 if ((ext2_use_xip(sb
)) && (sb
->s_blocksize
!= PAGE_SIZE
)) {
1242 ext2_msg(sb
, KERN_WARNING
,
1243 "warning: unsupported blocksize for xip");
1249 if ((sbi
->s_mount_opt
^ old_mount_opt
) & EXT2_MOUNT_XIP
) {
1250 ext2_msg(sb
, KERN_WARNING
, "warning: refusing change of "
1251 "xip flag with busy inodes while remounting");
1252 sbi
->s_mount_opt
&= ~EXT2_MOUNT_XIP
;
1253 sbi
->s_mount_opt
|= old_mount_opt
& EXT2_MOUNT_XIP
;
1255 if ((*flags
& MS_RDONLY
) == (sb
->s_flags
& MS_RDONLY
)) {
1256 spin_unlock(&sbi
->s_lock
);
1259 if (*flags
& MS_RDONLY
) {
1260 if (le16_to_cpu(es
->s_state
) & EXT2_VALID_FS
||
1261 !(sbi
->s_mount_state
& EXT2_VALID_FS
)) {
1262 spin_unlock(&sbi
->s_lock
);
1267 * OK, we are remounting a valid rw partition rdonly, so set
1268 * the rdonly flag and then mark the partition as valid again.
1270 es
->s_state
= cpu_to_le16(sbi
->s_mount_state
);
1271 es
->s_mtime
= cpu_to_le32(get_seconds());
1272 spin_unlock(&sbi
->s_lock
);
1274 err
= dquot_suspend(sb
, -1);
1276 spin_lock(&sbi
->s_lock
);
1280 ext2_sync_super(sb
, es
, 1);
1282 __le32 ret
= EXT2_HAS_RO_COMPAT_FEATURE(sb
,
1283 ~EXT2_FEATURE_RO_COMPAT_SUPP
);
1285 ext2_msg(sb
, KERN_WARNING
,
1286 "warning: couldn't remount RDWR because of "
1287 "unsupported optional features (%x).",
1293 * Mounting a RDONLY partition read-write, so reread and
1294 * store the current valid flag. (It may have been changed
1295 * by e2fsck since we originally mounted the partition.)
1297 sbi
->s_mount_state
= le16_to_cpu(es
->s_state
);
1298 if (!ext2_setup_super (sb
, es
, 0))
1299 sb
->s_flags
&= ~MS_RDONLY
;
1300 spin_unlock(&sbi
->s_lock
);
1302 ext2_write_super(sb
);
1304 dquot_resume(sb
, -1);
1309 sbi
->s_mount_opt
= old_opts
.s_mount_opt
;
1310 sbi
->s_resuid
= old_opts
.s_resuid
;
1311 sbi
->s_resgid
= old_opts
.s_resgid
;
1312 sb
->s_flags
= old_sb_flags
;
1313 spin_unlock(&sbi
->s_lock
);
1317 static int ext2_statfs (struct dentry
* dentry
, struct kstatfs
* buf
)
1319 struct super_block
*sb
= dentry
->d_sb
;
1320 struct ext2_sb_info
*sbi
= EXT2_SB(sb
);
1321 struct ext2_super_block
*es
= sbi
->s_es
;
1324 spin_lock(&sbi
->s_lock
);
1326 if (test_opt (sb
, MINIX_DF
))
1327 sbi
->s_overhead_last
= 0;
1328 else if (sbi
->s_blocks_last
!= le32_to_cpu(es
->s_blocks_count
)) {
1329 unsigned long i
, overhead
= 0;
1333 * Compute the overhead (FS structures). This is constant
1334 * for a given filesystem unless the number of block groups
1335 * changes so we cache the previous value until it does.
1339 * All of the blocks before first_data_block are
1342 overhead
= le32_to_cpu(es
->s_first_data_block
);
1345 * Add the overhead attributed to the superblock and
1346 * block group descriptors. If the sparse superblocks
1347 * feature is turned on, then not all groups have this.
1349 for (i
= 0; i
< sbi
->s_groups_count
; i
++)
1350 overhead
+= ext2_bg_has_super(sb
, i
) +
1351 ext2_bg_num_gdb(sb
, i
);
1354 * Every block group has an inode bitmap, a block
1355 * bitmap, and an inode table.
1357 overhead
+= (sbi
->s_groups_count
*
1358 (2 + sbi
->s_itb_per_group
));
1359 sbi
->s_overhead_last
= overhead
;
1361 sbi
->s_blocks_last
= le32_to_cpu(es
->s_blocks_count
);
1364 buf
->f_type
= EXT2_SUPER_MAGIC
;
1365 buf
->f_bsize
= sb
->s_blocksize
;
1366 buf
->f_blocks
= le32_to_cpu(es
->s_blocks_count
) - sbi
->s_overhead_last
;
1367 buf
->f_bfree
= ext2_count_free_blocks(sb
);
1368 es
->s_free_blocks_count
= cpu_to_le32(buf
->f_bfree
);
1369 buf
->f_bavail
= buf
->f_bfree
- le32_to_cpu(es
->s_r_blocks_count
);
1370 if (buf
->f_bfree
< le32_to_cpu(es
->s_r_blocks_count
))
1372 buf
->f_files
= le32_to_cpu(es
->s_inodes_count
);
1373 buf
->f_ffree
= ext2_count_free_inodes(sb
);
1374 es
->s_free_inodes_count
= cpu_to_le32(buf
->f_ffree
);
1375 buf
->f_namelen
= EXT2_NAME_LEN
;
1376 fsid
= le64_to_cpup((void *)es
->s_uuid
) ^
1377 le64_to_cpup((void *)es
->s_uuid
+ sizeof(u64
));
1378 buf
->f_fsid
.val
[0] = fsid
& 0xFFFFFFFFUL
;
1379 buf
->f_fsid
.val
[1] = (fsid
>> 32) & 0xFFFFFFFFUL
;
1380 spin_unlock(&sbi
->s_lock
);
1384 static struct dentry
*ext2_mount(struct file_system_type
*fs_type
,
1385 int flags
, const char *dev_name
, void *data
)
1387 return mount_bdev(fs_type
, flags
, dev_name
, data
, ext2_fill_super
);
1392 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1393 * acquiring the locks... As quota files are never truncated and quota code
1394 * itself serializes the operations (and no one else should touch the files)
1395 * we don't have to be afraid of races */
1396 static ssize_t
ext2_quota_read(struct super_block
*sb
, int type
, char *data
,
1397 size_t len
, loff_t off
)
1399 struct inode
*inode
= sb_dqopt(sb
)->files
[type
];
1400 sector_t blk
= off
>> EXT2_BLOCK_SIZE_BITS(sb
);
1402 int offset
= off
& (sb
->s_blocksize
- 1);
1405 struct buffer_head tmp_bh
;
1406 struct buffer_head
*bh
;
1407 loff_t i_size
= i_size_read(inode
);
1411 if (off
+len
> i_size
)
1414 while (toread
> 0) {
1415 tocopy
= sb
->s_blocksize
- offset
< toread
?
1416 sb
->s_blocksize
- offset
: toread
;
1419 tmp_bh
.b_size
= sb
->s_blocksize
;
1420 err
= ext2_get_block(inode
, blk
, &tmp_bh
, 0);
1423 if (!buffer_mapped(&tmp_bh
)) /* A hole? */
1424 memset(data
, 0, tocopy
);
1426 bh
= sb_bread(sb
, tmp_bh
.b_blocknr
);
1429 memcpy(data
, bh
->b_data
+offset
, tocopy
);
1440 /* Write to quotafile */
1441 static ssize_t
ext2_quota_write(struct super_block
*sb
, int type
,
1442 const char *data
, size_t len
, loff_t off
)
1444 struct inode
*inode
= sb_dqopt(sb
)->files
[type
];
1445 sector_t blk
= off
>> EXT2_BLOCK_SIZE_BITS(sb
);
1447 int offset
= off
& (sb
->s_blocksize
- 1);
1449 size_t towrite
= len
;
1450 struct buffer_head tmp_bh
;
1451 struct buffer_head
*bh
;
1453 while (towrite
> 0) {
1454 tocopy
= sb
->s_blocksize
- offset
< towrite
?
1455 sb
->s_blocksize
- offset
: towrite
;
1458 err
= ext2_get_block(inode
, blk
, &tmp_bh
, 1);
1461 if (offset
|| tocopy
!= EXT2_BLOCK_SIZE(sb
))
1462 bh
= sb_bread(sb
, tmp_bh
.b_blocknr
);
1464 bh
= sb_getblk(sb
, tmp_bh
.b_blocknr
);
1470 memcpy(bh
->b_data
+offset
, data
, tocopy
);
1471 flush_dcache_page(bh
->b_page
);
1472 set_buffer_uptodate(bh
);
1473 mark_buffer_dirty(bh
);
1484 if (inode
->i_size
< off
+len
-towrite
)
1485 i_size_write(inode
, off
+len
-towrite
);
1487 inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
1488 mark_inode_dirty(inode
);
1489 return len
- towrite
;
1494 static struct file_system_type ext2_fs_type
= {
1495 .owner
= THIS_MODULE
,
1497 .mount
= ext2_mount
,
1498 .kill_sb
= kill_block_super
,
1499 .fs_flags
= FS_REQUIRES_DEV
,
1502 static int __init
init_ext2_fs(void)
1504 int err
= init_ext2_xattr();
1507 err
= init_inodecache();
1510 err
= register_filesystem(&ext2_fs_type
);
1515 destroy_inodecache();
1521 static void __exit
exit_ext2_fs(void)
1523 unregister_filesystem(&ext2_fs_type
);
1524 destroy_inodecache();
1528 MODULE_AUTHOR("Remy Card and others");
1529 MODULE_DESCRIPTION("Second Extended Filesystem");
1530 MODULE_LICENSE("GPL");
1531 module_init(init_ext2_fs
)
1532 module_exit(exit_ext2_fs
)