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/smp_lock.h>
30 #include <linux/vfs.h>
31 #include <linux/seq_file.h>
32 #include <linux/mount.h>
33 #include <linux/log2.h>
34 #include <asm/uaccess.h>
40 static void ext2_sync_super(struct super_block *sb,
41 struct ext2_super_block *es);
42 static int ext2_remount (struct super_block * sb, int * flags, char * data);
43 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
45 void ext2_error (struct super_block * sb, const char * function,
46 const char * fmt, ...)
49 struct ext2_sb_info *sbi = EXT2_SB(sb);
50 struct ext2_super_block *es = sbi->s_es;
52 if (!(sb->s_flags & MS_RDONLY)) {
53 sbi->s_mount_state |= EXT2_ERROR_FS;
54 es->s_state |= cpu_to_le16(EXT2_ERROR_FS);
55 ext2_sync_super(sb, es);
59 printk(KERN_CRIT "EXT2-fs error (device %s): %s: ",sb->s_id, function);
64 if (test_opt(sb, ERRORS_PANIC))
65 panic("EXT2-fs panic from previous error\n");
66 if (test_opt(sb, ERRORS_RO)) {
67 printk("Remounting filesystem read-only\n");
68 sb->s_flags |= MS_RDONLY;
72 void ext2_warning (struct super_block * sb, const char * function,
73 const char * fmt, ...)
78 printk(KERN_WARNING "EXT2-fs warning (device %s): %s: ",
85 void ext2_update_dynamic_rev(struct super_block *sb)
87 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
89 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
92 ext2_warning(sb, __FUNCTION__,
93 "updating to rev %d because of new feature flag, "
94 "running e2fsck is recommended",
97 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
98 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
99 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
100 /* leave es->s_feature_*compat flags alone */
101 /* es->s_uuid will be set by e2fsck if empty */
104 * The rest of the superblock fields should be zero, and if not it
105 * means they are likely already in use, so leave them alone. We
106 * can leave it up to e2fsck to clean up any inconsistencies there.
110 static void ext2_put_super (struct super_block * sb)
114 struct ext2_sb_info *sbi = EXT2_SB(sb);
116 ext2_xattr_put_super(sb);
117 if (!(sb->s_flags & MS_RDONLY)) {
118 struct ext2_super_block *es = sbi->s_es;
120 es->s_state = cpu_to_le16(sbi->s_mount_state);
121 ext2_sync_super(sb, es);
123 db_count = sbi->s_gdb_count;
124 for (i = 0; i < db_count; i++)
125 if (sbi->s_group_desc[i])
126 brelse (sbi->s_group_desc[i]);
127 kfree(sbi->s_group_desc);
129 percpu_counter_destroy(&sbi->s_freeblocks_counter);
130 percpu_counter_destroy(&sbi->s_freeinodes_counter);
131 percpu_counter_destroy(&sbi->s_dirs_counter);
133 sb->s_fs_info = NULL;
139 static struct kmem_cache * ext2_inode_cachep;
141 static struct inode *ext2_alloc_inode(struct super_block *sb)
143 struct ext2_inode_info *ei;
144 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL);
147 #ifdef CONFIG_EXT2_FS_POSIX_ACL
148 ei->i_acl = EXT2_ACL_NOT_CACHED;
149 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
151 ei->i_block_alloc_info = NULL;
152 ei->vfs_inode.i_version = 1;
153 return &ei->vfs_inode;
156 static void ext2_destroy_inode(struct inode *inode)
158 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
161 static void init_once(struct kmem_cache * cachep, void *foo)
163 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
165 rwlock_init(&ei->i_meta_lock);
166 #ifdef CONFIG_EXT2_FS_XATTR
167 init_rwsem(&ei->xattr_sem);
169 mutex_init(&ei->truncate_mutex);
170 inode_init_once(&ei->vfs_inode);
173 static int init_inodecache(void)
175 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
176 sizeof(struct ext2_inode_info),
177 0, (SLAB_RECLAIM_ACCOUNT|
180 if (ext2_inode_cachep == NULL)
185 static void destroy_inodecache(void)
187 kmem_cache_destroy(ext2_inode_cachep);
190 static void ext2_clear_inode(struct inode *inode)
192 struct ext2_block_alloc_info *rsv = EXT2_I(inode)->i_block_alloc_info;
193 #ifdef CONFIG_EXT2_FS_POSIX_ACL
194 struct ext2_inode_info *ei = EXT2_I(inode);
196 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) {
197 posix_acl_release(ei->i_acl);
198 ei->i_acl = EXT2_ACL_NOT_CACHED;
200 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) {
201 posix_acl_release(ei->i_default_acl);
202 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
205 ext2_discard_reservation(inode);
206 EXT2_I(inode)->i_block_alloc_info = NULL;
211 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
213 struct super_block *sb = vfs->mnt_sb;
214 struct ext2_sb_info *sbi = EXT2_SB(sb);
215 struct ext2_super_block *es = sbi->s_es;
216 unsigned long def_mount_opts;
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 (sbi->s_resuid != EXT2_DEF_RESUID ||
229 le16_to_cpu(es->s_def_resuid) != EXT2_DEF_RESUID) {
230 seq_printf(seq, ",resuid=%u", sbi->s_resuid);
232 if (sbi->s_resgid != EXT2_DEF_RESGID ||
233 le16_to_cpu(es->s_def_resgid) != EXT2_DEF_RESGID) {
234 seq_printf(seq, ",resgid=%u", sbi->s_resgid);
236 if (test_opt(sb, ERRORS_RO)) {
237 int def_errors = le16_to_cpu(es->s_errors);
239 if (def_errors == EXT2_ERRORS_PANIC ||
240 def_errors == EXT2_ERRORS_CONTINUE) {
241 seq_puts(seq, ",errors=remount-ro");
244 if (test_opt(sb, ERRORS_CONT))
245 seq_puts(seq, ",errors=continue");
246 if (test_opt(sb, ERRORS_PANIC))
247 seq_puts(seq, ",errors=panic");
248 if (test_opt(sb, NO_UID32))
249 seq_puts(seq, ",nouid32");
250 if (test_opt(sb, DEBUG))
251 seq_puts(seq, ",debug");
252 if (test_opt(sb, OLDALLOC))
253 seq_puts(seq, ",oldalloc");
255 #ifdef CONFIG_EXT2_FS_XATTR
256 if (test_opt(sb, XATTR_USER))
257 seq_puts(seq, ",user_xattr");
258 if (!test_opt(sb, XATTR_USER) &&
259 (def_mount_opts & EXT2_DEFM_XATTR_USER)) {
260 seq_puts(seq, ",nouser_xattr");
264 #ifdef CONFIG_EXT2_FS_POSIX_ACL
265 if (test_opt(sb, POSIX_ACL))
266 seq_puts(seq, ",acl");
267 if (!test_opt(sb, POSIX_ACL) && (def_mount_opts & EXT2_DEFM_ACL))
268 seq_puts(seq, ",noacl");
271 if (test_opt(sb, NOBH))
272 seq_puts(seq, ",nobh");
274 #if defined(CONFIG_QUOTA)
275 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
276 seq_puts(seq, ",usrquota");
278 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
279 seq_puts(seq, ",grpquota");
282 #if defined(CONFIG_EXT2_FS_XIP)
283 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
284 seq_puts(seq, ",xip");
287 if (!test_opt(sb, RESERVATION))
288 seq_puts(seq, ",noreservation");
294 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
295 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
298 static const struct super_operations ext2_sops = {
299 .alloc_inode = ext2_alloc_inode,
300 .destroy_inode = ext2_destroy_inode,
301 .write_inode = ext2_write_inode,
302 .delete_inode = ext2_delete_inode,
303 .put_super = ext2_put_super,
304 .write_super = ext2_write_super,
305 .statfs = ext2_statfs,
306 .remount_fs = ext2_remount,
307 .clear_inode = ext2_clear_inode,
308 .show_options = ext2_show_options,
310 .quota_read = ext2_quota_read,
311 .quota_write = ext2_quota_write,
315 static struct inode *ext2_nfs_get_inode(struct super_block *sb,
316 u64 ino, u32 generation)
320 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
321 return ERR_PTR(-ESTALE);
322 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
323 return ERR_PTR(-ESTALE);
325 /* iget isn't really right if the inode is currently unallocated!!
326 * ext2_read_inode currently does appropriate checks, but
327 * it might be "neater" to call ext2_get_inode first and check
328 * if the inode is valid.....
330 inode = ext2_iget(sb, ino);
332 return ERR_CAST(inode);
333 if (generation && inode->i_generation != generation) {
334 /* we didn't find the right inode.. */
336 return ERR_PTR(-ESTALE);
341 static struct dentry *ext2_fh_to_dentry(struct super_block *sb, struct fid *fid,
342 int fh_len, int fh_type)
344 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
348 static struct dentry *ext2_fh_to_parent(struct super_block *sb, struct fid *fid,
349 int fh_len, int fh_type)
351 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
355 /* Yes, most of these are left as NULL!!
356 * A NULL value implies the default, which works with ext2-like file
357 * systems, but can be improved upon.
358 * Currently only get_parent is required.
360 static const struct export_operations ext2_export_ops = {
361 .fh_to_dentry = ext2_fh_to_dentry,
362 .fh_to_parent = ext2_fh_to_parent,
363 .get_parent = ext2_get_parent,
366 static unsigned long get_sb_block(void **data)
368 unsigned long sb_block;
369 char *options = (char *) *data;
371 if (!options || strncmp(options, "sb=", 3) != 0)
372 return 1; /* Default location */
374 sb_block = simple_strtoul(options, &options, 0);
375 if (*options && *options != ',') {
376 printk("EXT2-fs: Invalid sb specification: %s\n",
382 *data = (void *) options;
387 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
388 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
389 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
390 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
391 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
392 Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation
395 static match_table_t tokens = {
396 {Opt_bsd_df, "bsddf"},
397 {Opt_minix_df, "minixdf"},
398 {Opt_grpid, "grpid"},
399 {Opt_grpid, "bsdgroups"},
400 {Opt_nogrpid, "nogrpid"},
401 {Opt_nogrpid, "sysvgroups"},
402 {Opt_resgid, "resgid=%u"},
403 {Opt_resuid, "resuid=%u"},
405 {Opt_err_cont, "errors=continue"},
406 {Opt_err_panic, "errors=panic"},
407 {Opt_err_ro, "errors=remount-ro"},
408 {Opt_nouid32, "nouid32"},
409 {Opt_nocheck, "check=none"},
410 {Opt_nocheck, "nocheck"},
411 {Opt_debug, "debug"},
412 {Opt_oldalloc, "oldalloc"},
413 {Opt_orlov, "orlov"},
415 {Opt_user_xattr, "user_xattr"},
416 {Opt_nouser_xattr, "nouser_xattr"},
418 {Opt_noacl, "noacl"},
420 {Opt_grpquota, "grpquota"},
421 {Opt_ignore, "noquota"},
422 {Opt_quota, "quota"},
423 {Opt_usrquota, "usrquota"},
424 {Opt_reservation, "reservation"},
425 {Opt_noreservation, "noreservation"},
429 static int parse_options (char * options,
430 struct ext2_sb_info *sbi)
433 substring_t args[MAX_OPT_ARGS];
439 while ((p = strsep (&options, ",")) != NULL) {
444 token = match_token(p, tokens, args);
447 clear_opt (sbi->s_mount_opt, MINIX_DF);
450 set_opt (sbi->s_mount_opt, MINIX_DF);
453 set_opt (sbi->s_mount_opt, GRPID);
456 clear_opt (sbi->s_mount_opt, GRPID);
459 if (match_int(&args[0], &option))
461 sbi->s_resuid = option;
464 if (match_int(&args[0], &option))
466 sbi->s_resgid = option;
469 /* handled by get_sb_block() instead of here */
470 /* *sb_block = match_int(&args[0]); */
473 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
474 clear_opt (sbi->s_mount_opt, ERRORS_RO);
475 set_opt (sbi->s_mount_opt, ERRORS_PANIC);
478 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
479 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
480 set_opt (sbi->s_mount_opt, ERRORS_RO);
483 clear_opt (sbi->s_mount_opt, ERRORS_RO);
484 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
485 set_opt (sbi->s_mount_opt, ERRORS_CONT);
488 set_opt (sbi->s_mount_opt, NO_UID32);
491 clear_opt (sbi->s_mount_opt, CHECK);
494 set_opt (sbi->s_mount_opt, DEBUG);
497 set_opt (sbi->s_mount_opt, OLDALLOC);
500 clear_opt (sbi->s_mount_opt, OLDALLOC);
503 set_opt (sbi->s_mount_opt, NOBH);
505 #ifdef CONFIG_EXT2_FS_XATTR
507 set_opt (sbi->s_mount_opt, XATTR_USER);
509 case Opt_nouser_xattr:
510 clear_opt (sbi->s_mount_opt, XATTR_USER);
514 case Opt_nouser_xattr:
515 printk("EXT2 (no)user_xattr options not supported\n");
518 #ifdef CONFIG_EXT2_FS_POSIX_ACL
520 set_opt(sbi->s_mount_opt, POSIX_ACL);
523 clear_opt(sbi->s_mount_opt, POSIX_ACL);
528 printk("EXT2 (no)acl options not supported\n");
532 #ifdef CONFIG_EXT2_FS_XIP
533 set_opt (sbi->s_mount_opt, XIP);
535 printk("EXT2 xip option not supported\n");
539 #if defined(CONFIG_QUOTA)
542 set_opt(sbi->s_mount_opt, USRQUOTA);
546 set_opt(sbi->s_mount_opt, GRPQUOTA);
553 "EXT2-fs: quota operations not supported.\n");
558 case Opt_reservation:
559 set_opt(sbi->s_mount_opt, RESERVATION);
560 printk("reservations ON\n");
562 case Opt_noreservation:
563 clear_opt(sbi->s_mount_opt, RESERVATION);
564 printk("reservations OFF\n");
575 static int ext2_setup_super (struct super_block * sb,
576 struct ext2_super_block * es,
580 struct ext2_sb_info *sbi = EXT2_SB(sb);
582 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
583 printk ("EXT2-fs warning: revision level too high, "
584 "forcing read-only mode\n");
589 if (!(sbi->s_mount_state & EXT2_VALID_FS))
590 printk ("EXT2-fs warning: mounting unchecked fs, "
591 "running e2fsck is recommended\n");
592 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
593 printk ("EXT2-fs warning: mounting fs with errors, "
594 "running e2fsck is recommended\n");
595 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
596 le16_to_cpu(es->s_mnt_count) >=
597 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
598 printk ("EXT2-fs warning: maximal mount count reached, "
599 "running e2fsck is recommended\n");
600 else if (le32_to_cpu(es->s_checkinterval) &&
601 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
602 printk ("EXT2-fs warning: checktime reached, "
603 "running e2fsck is recommended\n");
604 if (!le16_to_cpu(es->s_max_mnt_count))
605 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
606 le16_add_cpu(&es->s_mnt_count, 1);
607 ext2_write_super(sb);
608 if (test_opt (sb, DEBUG))
609 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
610 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
611 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
614 EXT2_BLOCKS_PER_GROUP(sb),
615 EXT2_INODES_PER_GROUP(sb),
620 static int ext2_check_descriptors(struct super_block *sb)
623 struct ext2_sb_info *sbi = EXT2_SB(sb);
624 unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
625 unsigned long last_block;
627 ext2_debug ("Checking group descriptors");
629 for (i = 0; i < sbi->s_groups_count; i++) {
630 struct ext2_group_desc *gdp = ext2_get_group_desc(sb, i, NULL);
632 if (i == sbi->s_groups_count - 1)
633 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
635 last_block = first_block +
636 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
638 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
639 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
641 ext2_error (sb, "ext2_check_descriptors",
642 "Block bitmap for group %d"
643 " not in group (block %lu)!",
644 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
647 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
648 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
650 ext2_error (sb, "ext2_check_descriptors",
651 "Inode bitmap for group %d"
652 " not in group (block %lu)!",
653 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
656 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
657 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
660 ext2_error (sb, "ext2_check_descriptors",
661 "Inode table for group %d"
662 " not in group (block %lu)!",
663 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
666 first_block += EXT2_BLOCKS_PER_GROUP(sb);
672 * Maximal file size. There is a direct, and {,double-,triple-}indirect
673 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
674 * We need to be 1 filesystem block less than the 2^32 sector limit.
676 static loff_t ext2_max_size(int bits)
678 loff_t res = EXT2_NDIR_BLOCKS;
682 /* This is calculated to be the largest file size for a
683 * dense, file such that the total number of
684 * sectors in the file, including data and all indirect blocks,
685 * does not exceed 2^32 -1
686 * __u32 i_blocks representing the total number of
687 * 512 bytes blocks of the file
689 upper_limit = (1LL << 32) - 1;
691 /* total blocks in file system block size */
692 upper_limit >>= (bits - 9);
695 /* indirect blocks */
697 /* double indirect blocks */
698 meta_blocks += 1 + (1LL << (bits-2));
699 /* tripple indirect blocks */
700 meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
702 upper_limit -= meta_blocks;
703 upper_limit <<= bits;
705 res += 1LL << (bits-2);
706 res += 1LL << (2*(bits-2));
707 res += 1LL << (3*(bits-2));
709 if (res > upper_limit)
712 if (res > MAX_LFS_FILESIZE)
713 res = MAX_LFS_FILESIZE;
718 static unsigned long descriptor_loc(struct super_block *sb,
719 unsigned long logic_sb_block,
722 struct ext2_sb_info *sbi = EXT2_SB(sb);
723 unsigned long bg, first_data_block, first_meta_bg;
726 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
727 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
729 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
731 return (logic_sb_block + nr + 1);
732 bg = sbi->s_desc_per_block * nr;
733 if (ext2_bg_has_super(sb, bg))
735 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
738 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
740 struct buffer_head * bh;
741 struct ext2_sb_info * sbi;
742 struct ext2_super_block * es;
745 unsigned long sb_block = get_sb_block(&data);
746 unsigned long logic_sb_block;
747 unsigned long offset = 0;
748 unsigned long def_mount_opts;
750 int blocksize = BLOCK_SIZE;
756 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
760 sbi->s_sb_block = sb_block;
763 * See what the current blocksize for the device is, and
764 * use that as the blocksize. Otherwise (or if the blocksize
765 * is smaller than the default) use the default.
766 * This is important for devices that have a hardware
767 * sectorsize that is larger than the default.
769 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
771 printk ("EXT2-fs: unable to set blocksize\n");
776 * If the superblock doesn't start on a hardware sector boundary,
777 * calculate the offset.
779 if (blocksize != BLOCK_SIZE) {
780 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
781 offset = (sb_block*BLOCK_SIZE) % blocksize;
783 logic_sb_block = sb_block;
786 if (!(bh = sb_bread(sb, logic_sb_block))) {
787 printk ("EXT2-fs: unable to read superblock\n");
791 * Note: s_es must be initialized as soon as possible because
792 * some ext2 macro-instructions depend on its value
794 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
796 sb->s_magic = le16_to_cpu(es->s_magic);
798 if (sb->s_magic != EXT2_SUPER_MAGIC)
801 /* Set defaults before we parse the mount options */
802 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
803 if (def_mount_opts & EXT2_DEFM_DEBUG)
804 set_opt(sbi->s_mount_opt, DEBUG);
805 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
806 set_opt(sbi->s_mount_opt, GRPID);
807 if (def_mount_opts & EXT2_DEFM_UID16)
808 set_opt(sbi->s_mount_opt, NO_UID32);
809 #ifdef CONFIG_EXT2_FS_XATTR
810 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
811 set_opt(sbi->s_mount_opt, XATTR_USER);
813 #ifdef CONFIG_EXT2_FS_POSIX_ACL
814 if (def_mount_opts & EXT2_DEFM_ACL)
815 set_opt(sbi->s_mount_opt, POSIX_ACL);
818 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
819 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
820 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_CONTINUE)
821 set_opt(sbi->s_mount_opt, ERRORS_CONT);
823 set_opt(sbi->s_mount_opt, ERRORS_RO);
825 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
826 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
828 set_opt(sbi->s_mount_opt, RESERVATION);
830 if (!parse_options ((char *) data, sbi))
833 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
834 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
837 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
838 EXT2_MOUNT_XIP if not */
840 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
841 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
842 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
843 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
844 printk("EXT2-fs warning: feature flags set on rev 0 fs, "
845 "running e2fsck is recommended\n");
847 * Check feature flags regardless of the revision level, since we
848 * previously didn't change the revision level when setting the flags,
849 * so there is a chance incompat flags are set on a rev 0 filesystem.
851 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
853 printk("EXT2-fs: %s: couldn't mount because of "
854 "unsupported optional features (%x).\n",
855 sb->s_id, le32_to_cpu(features));
858 if (!(sb->s_flags & MS_RDONLY) &&
859 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
860 printk("EXT2-fs: %s: couldn't mount RDWR because of "
861 "unsupported optional features (%x).\n",
862 sb->s_id, le32_to_cpu(features));
866 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
868 if (ext2_use_xip(sb) && blocksize != PAGE_SIZE) {
870 printk("XIP: Unsupported blocksize\n");
874 /* If the blocksize doesn't match, re-read the thing.. */
875 if (sb->s_blocksize != blocksize) {
878 if (!sb_set_blocksize(sb, blocksize)) {
879 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
883 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
884 offset = (sb_block*BLOCK_SIZE) % blocksize;
885 bh = sb_bread(sb, logic_sb_block);
887 printk("EXT2-fs: Couldn't read superblock on "
891 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
893 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
894 printk ("EXT2-fs: Magic mismatch, very weird !\n");
899 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
901 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
902 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
903 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
905 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
906 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
907 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
908 !is_power_of_2(sbi->s_inode_size) ||
909 (sbi->s_inode_size > blocksize)) {
910 printk ("EXT2-fs: unsupported inode size: %d\n",
916 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
917 le32_to_cpu(es->s_log_frag_size);
918 if (sbi->s_frag_size == 0)
920 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
922 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
923 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
924 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
926 if (EXT2_INODE_SIZE(sb) == 0)
928 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
929 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
931 sbi->s_itb_per_group = sbi->s_inodes_per_group /
932 sbi->s_inodes_per_block;
933 sbi->s_desc_per_block = sb->s_blocksize /
934 sizeof (struct ext2_group_desc);
936 sbi->s_mount_state = le16_to_cpu(es->s_state);
937 sbi->s_addr_per_block_bits =
938 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
939 sbi->s_desc_per_block_bits =
940 ilog2 (EXT2_DESC_PER_BLOCK(sb));
942 if (sb->s_magic != EXT2_SUPER_MAGIC)
945 if (sb->s_blocksize != bh->b_size) {
947 printk ("VFS: Unsupported blocksize on dev "
952 if (sb->s_blocksize != sbi->s_frag_size) {
953 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
954 sbi->s_frag_size, sb->s_blocksize);
958 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
959 printk ("EXT2-fs: #blocks per group too big: %lu\n",
960 sbi->s_blocks_per_group);
963 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
964 printk ("EXT2-fs: #fragments per group too big: %lu\n",
965 sbi->s_frags_per_group);
968 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
969 printk ("EXT2-fs: #inodes per group too big: %lu\n",
970 sbi->s_inodes_per_group);
974 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
976 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
977 le32_to_cpu(es->s_first_data_block) - 1)
978 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
979 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
980 EXT2_DESC_PER_BLOCK(sb);
981 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
982 if (sbi->s_group_desc == NULL) {
983 printk ("EXT2-fs: not enough memory\n");
986 bgl_lock_init(&sbi->s_blockgroup_lock);
987 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
989 printk ("EXT2-fs: not enough memory\n");
990 goto failed_mount_group_desc;
992 for (i = 0; i < db_count; i++) {
993 block = descriptor_loc(sb, logic_sb_block, i);
994 sbi->s_group_desc[i] = sb_bread(sb, block);
995 if (!sbi->s_group_desc[i]) {
996 for (j = 0; j < i; j++)
997 brelse (sbi->s_group_desc[j]);
998 printk ("EXT2-fs: unable to read group descriptors\n");
999 goto failed_mount_group_desc;
1002 if (!ext2_check_descriptors (sb)) {
1003 printk ("EXT2-fs: group descriptors corrupted!\n");
1006 sbi->s_gdb_count = db_count;
1007 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
1008 spin_lock_init(&sbi->s_next_gen_lock);
1010 /* per fileystem reservation list head & lock */
1011 spin_lock_init(&sbi->s_rsv_window_lock);
1012 sbi->s_rsv_window_root = RB_ROOT;
1014 * Add a single, static dummy reservation to the start of the
1015 * reservation window list --- it gives us a placeholder for
1016 * append-at-start-of-list which makes the allocation logic
1019 sbi->s_rsv_window_head.rsv_start = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1020 sbi->s_rsv_window_head.rsv_end = EXT2_RESERVE_WINDOW_NOT_ALLOCATED;
1021 sbi->s_rsv_window_head.rsv_alloc_hit = 0;
1022 sbi->s_rsv_window_head.rsv_goal_size = 0;
1023 ext2_rsv_window_add(sb, &sbi->s_rsv_window_head);
1025 err = percpu_counter_init(&sbi->s_freeblocks_counter,
1026 ext2_count_free_blocks(sb));
1028 err = percpu_counter_init(&sbi->s_freeinodes_counter,
1029 ext2_count_free_inodes(sb));
1032 err = percpu_counter_init(&sbi->s_dirs_counter,
1033 ext2_count_dirs(sb));
1036 printk(KERN_ERR "EXT2-fs: insufficient memory\n");
1040 * set up enough so that it can read an inode
1042 sb->s_op = &ext2_sops;
1043 sb->s_export_op = &ext2_export_ops;
1044 sb->s_xattr = ext2_xattr_handlers;
1045 root = ext2_iget(sb, EXT2_ROOT_INO);
1047 ret = PTR_ERR(root);
1050 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
1052 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
1056 sb->s_root = d_alloc_root(root);
1059 printk(KERN_ERR "EXT2-fs: get root inode failed\n");
1063 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1064 ext2_warning(sb, __FUNCTION__,
1065 "mounting ext3 filesystem as ext2");
1066 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
1071 printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
1075 percpu_counter_destroy(&sbi->s_freeblocks_counter);
1076 percpu_counter_destroy(&sbi->s_freeinodes_counter);
1077 percpu_counter_destroy(&sbi->s_dirs_counter);
1079 for (i = 0; i < db_count; i++)
1080 brelse(sbi->s_group_desc[i]);
1081 failed_mount_group_desc:
1082 kfree(sbi->s_group_desc);
1083 kfree(sbi->s_debts);
1087 sb->s_fs_info = NULL;
1092 static void ext2_commit_super (struct super_block * sb,
1093 struct ext2_super_block * es)
1095 es->s_wtime = cpu_to_le32(get_seconds());
1096 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1100 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
1102 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1103 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1104 es->s_wtime = cpu_to_le32(get_seconds());
1105 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1106 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1111 * In the second extended file system, it is not necessary to
1112 * write the super block since we use a mapping of the
1113 * disk super block in a buffer.
1115 * However, this function is still used to set the fs valid
1116 * flags to 0. We need to set this flag to 0 since the fs
1117 * may have been checked while mounted and e2fsck may have
1118 * set s_state to EXT2_VALID_FS after some corrections.
1121 void ext2_write_super (struct super_block * sb)
1123 struct ext2_super_block * es;
1125 if (!(sb->s_flags & MS_RDONLY)) {
1126 es = EXT2_SB(sb)->s_es;
1128 if (es->s_state & cpu_to_le16(EXT2_VALID_FS)) {
1129 ext2_debug ("setting valid to 0\n");
1130 es->s_state &= cpu_to_le16(~EXT2_VALID_FS);
1131 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1132 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1133 es->s_mtime = cpu_to_le32(get_seconds());
1134 ext2_sync_super(sb, es);
1136 ext2_commit_super (sb, es);
1142 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1144 struct ext2_sb_info * sbi = EXT2_SB(sb);
1145 struct ext2_super_block * es;
1146 unsigned long old_mount_opt = sbi->s_mount_opt;
1147 struct ext2_mount_options old_opts;
1148 unsigned long old_sb_flags;
1151 /* Store the old options */
1152 old_sb_flags = sb->s_flags;
1153 old_opts.s_mount_opt = sbi->s_mount_opt;
1154 old_opts.s_resuid = sbi->s_resuid;
1155 old_opts.s_resgid = sbi->s_resgid;
1158 * Allow the "check" option to be passed as a remount option.
1160 if (!parse_options (data, sbi)) {
1165 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1166 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1168 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
1169 EXT2_MOUNT_XIP if not */
1171 if ((ext2_use_xip(sb)) && (sb->s_blocksize != PAGE_SIZE)) {
1172 printk("XIP: Unsupported blocksize\n");
1178 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
1179 (old_mount_opt & EXT2_MOUNT_XIP)) &&
1180 invalidate_inodes(sb))
1181 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
1182 "xip remain in cache (no functional problem)");
1183 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1185 if (*flags & MS_RDONLY) {
1186 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1187 !(sbi->s_mount_state & EXT2_VALID_FS))
1190 * OK, we are remounting a valid rw partition rdonly, so set
1191 * the rdonly flag and then mark the partition as valid again.
1193 es->s_state = cpu_to_le16(sbi->s_mount_state);
1194 es->s_mtime = cpu_to_le32(get_seconds());
1196 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1197 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1199 printk("EXT2-fs: %s: couldn't remount RDWR because of "
1200 "unsupported optional features (%x).\n",
1201 sb->s_id, le32_to_cpu(ret));
1206 * Mounting a RDONLY partition read-write, so reread and
1207 * store the current valid flag. (It may have been changed
1208 * by e2fsck since we originally mounted the partition.)
1210 sbi->s_mount_state = le16_to_cpu(es->s_state);
1211 if (!ext2_setup_super (sb, es, 0))
1212 sb->s_flags &= ~MS_RDONLY;
1214 ext2_sync_super(sb, es);
1217 sbi->s_mount_opt = old_opts.s_mount_opt;
1218 sbi->s_resuid = old_opts.s_resuid;
1219 sbi->s_resgid = old_opts.s_resgid;
1220 sb->s_flags = old_sb_flags;
1224 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1226 struct super_block *sb = dentry->d_sb;
1227 struct ext2_sb_info *sbi = EXT2_SB(sb);
1228 struct ext2_super_block *es = sbi->s_es;
1231 if (test_opt (sb, MINIX_DF))
1232 sbi->s_overhead_last = 0;
1233 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1234 unsigned long i, overhead = 0;
1238 * Compute the overhead (FS structures). This is constant
1239 * for a given filesystem unless the number of block groups
1240 * changes so we cache the previous value until it does.
1244 * All of the blocks before first_data_block are
1247 overhead = le32_to_cpu(es->s_first_data_block);
1250 * Add the overhead attributed to the superblock and
1251 * block group descriptors. If the sparse superblocks
1252 * feature is turned on, then not all groups have this.
1254 for (i = 0; i < sbi->s_groups_count; i++)
1255 overhead += ext2_bg_has_super(sb, i) +
1256 ext2_bg_num_gdb(sb, i);
1259 * Every block group has an inode bitmap, a block
1260 * bitmap, and an inode table.
1262 overhead += (sbi->s_groups_count *
1263 (2 + sbi->s_itb_per_group));
1264 sbi->s_overhead_last = overhead;
1266 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1269 buf->f_type = EXT2_SUPER_MAGIC;
1270 buf->f_bsize = sb->s_blocksize;
1271 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1272 buf->f_bfree = ext2_count_free_blocks(sb);
1273 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1274 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1275 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1277 buf->f_files = le32_to_cpu(es->s_inodes_count);
1278 buf->f_ffree = ext2_count_free_inodes(sb);
1279 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1280 buf->f_namelen = EXT2_NAME_LEN;
1281 fsid = le64_to_cpup((void *)es->s_uuid) ^
1282 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1283 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1284 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1288 static int ext2_get_sb(struct file_system_type *fs_type,
1289 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
1291 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt);
1296 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1297 * acquiring the locks... As quota files are never truncated and quota code
1298 * itself serializes the operations (and noone else should touch the files)
1299 * we don't have to be afraid of races */
1300 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1301 size_t len, loff_t off)
1303 struct inode *inode = sb_dqopt(sb)->files[type];
1304 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1306 int offset = off & (sb->s_blocksize - 1);
1309 struct buffer_head tmp_bh;
1310 struct buffer_head *bh;
1311 loff_t i_size = i_size_read(inode);
1315 if (off+len > i_size)
1318 while (toread > 0) {
1319 tocopy = sb->s_blocksize - offset < toread ?
1320 sb->s_blocksize - offset : toread;
1323 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1326 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1327 memset(data, 0, tocopy);
1329 bh = sb_bread(sb, tmp_bh.b_blocknr);
1332 memcpy(data, bh->b_data+offset, tocopy);
1343 /* Write to quotafile */
1344 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1345 const char *data, size_t len, loff_t off)
1347 struct inode *inode = sb_dqopt(sb)->files[type];
1348 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1350 int offset = off & (sb->s_blocksize - 1);
1352 size_t towrite = len;
1353 struct buffer_head tmp_bh;
1354 struct buffer_head *bh;
1356 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
1357 while (towrite > 0) {
1358 tocopy = sb->s_blocksize - offset < towrite ?
1359 sb->s_blocksize - offset : towrite;
1362 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1365 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1366 bh = sb_bread(sb, tmp_bh.b_blocknr);
1368 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1374 memcpy(bh->b_data+offset, data, tocopy);
1375 flush_dcache_page(bh->b_page);
1376 set_buffer_uptodate(bh);
1377 mark_buffer_dirty(bh);
1388 if (inode->i_size < off+len-towrite)
1389 i_size_write(inode, off+len-towrite);
1391 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1392 mark_inode_dirty(inode);
1393 mutex_unlock(&inode->i_mutex);
1394 return len - towrite;
1399 static struct file_system_type ext2_fs_type = {
1400 .owner = THIS_MODULE,
1402 .get_sb = ext2_get_sb,
1403 .kill_sb = kill_block_super,
1404 .fs_flags = FS_REQUIRES_DEV,
1407 static int __init init_ext2_fs(void)
1409 int err = init_ext2_xattr();
1412 err = init_inodecache();
1415 err = register_filesystem(&ext2_fs_type);
1420 destroy_inodecache();
1426 static void __exit exit_ext2_fs(void)
1428 unregister_filesystem(&ext2_fs_type);
1429 destroy_inodecache();
1433 module_init(init_ext2_fs)
1434 module_exit(exit_ext2_fs)