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 <asm/uaccess.h>
39 static void ext2_sync_super(struct super_block *sb,
40 struct ext2_super_block *es);
41 static int ext2_remount (struct super_block * sb, int * flags, char * data);
42 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
44 void ext2_error (struct super_block * sb, const char * function,
45 const char * fmt, ...)
48 struct ext2_sb_info *sbi = EXT2_SB(sb);
49 struct ext2_super_block *es = sbi->s_es;
51 if (!(sb->s_flags & MS_RDONLY)) {
52 sbi->s_mount_state |= EXT2_ERROR_FS;
54 cpu_to_le16(le16_to_cpu(es->s_state) | 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->vfs_inode.i_version = 1;
152 return &ei->vfs_inode;
155 static void ext2_destroy_inode(struct inode *inode)
157 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
160 static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
162 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
164 rwlock_init(&ei->i_meta_lock);
165 #ifdef CONFIG_EXT2_FS_XATTR
166 init_rwsem(&ei->xattr_sem);
168 inode_init_once(&ei->vfs_inode);
171 static int init_inodecache(void)
173 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
174 sizeof(struct ext2_inode_info),
175 0, (SLAB_RECLAIM_ACCOUNT|
178 if (ext2_inode_cachep == NULL)
183 static void destroy_inodecache(void)
185 kmem_cache_destroy(ext2_inode_cachep);
188 static void ext2_clear_inode(struct inode *inode)
190 #ifdef CONFIG_EXT2_FS_POSIX_ACL
191 struct ext2_inode_info *ei = EXT2_I(inode);
193 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) {
194 posix_acl_release(ei->i_acl);
195 ei->i_acl = EXT2_ACL_NOT_CACHED;
197 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) {
198 posix_acl_release(ei->i_default_acl);
199 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
204 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
206 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb);
208 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID)
209 seq_puts(seq, ",grpid");
211 #if defined(CONFIG_QUOTA)
212 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
213 seq_puts(seq, ",usrquota");
215 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
216 seq_puts(seq, ",grpquota");
219 #if defined(CONFIG_EXT2_FS_XIP)
220 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
221 seq_puts(seq, ",xip");
228 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
229 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
232 static const struct super_operations ext2_sops = {
233 .alloc_inode = ext2_alloc_inode,
234 .destroy_inode = ext2_destroy_inode,
235 .read_inode = ext2_read_inode,
236 .write_inode = ext2_write_inode,
237 .put_inode = ext2_put_inode,
238 .delete_inode = ext2_delete_inode,
239 .put_super = ext2_put_super,
240 .write_super = ext2_write_super,
241 .statfs = ext2_statfs,
242 .remount_fs = ext2_remount,
243 .clear_inode = ext2_clear_inode,
244 .show_options = ext2_show_options,
246 .quota_read = ext2_quota_read,
247 .quota_write = ext2_quota_write,
251 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp)
254 unsigned long ino = objp[0];
255 __u32 generation = objp[1];
257 struct dentry *result;
259 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
260 return ERR_PTR(-ESTALE);
261 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
262 return ERR_PTR(-ESTALE);
264 /* iget isn't really right if the inode is currently unallocated!!
265 * ext2_read_inode currently does appropriate checks, but
266 * it might be "neater" to call ext2_get_inode first and check
267 * if the inode is valid.....
269 inode = iget(sb, ino);
271 return ERR_PTR(-ENOMEM);
272 if (is_bad_inode(inode) ||
273 (generation && inode->i_generation != generation)) {
274 /* we didn't find the right inode.. */
276 return ERR_PTR(-ESTALE);
278 /* now to find a dentry.
279 * If possible, get a well-connected one
281 result = d_alloc_anon(inode);
284 return ERR_PTR(-ENOMEM);
289 /* Yes, most of these are left as NULL!!
290 * A NULL value implies the default, which works with ext2-like file
291 * systems, but can be improved upon.
292 * Currently only get_parent is required.
294 static struct export_operations ext2_export_ops = {
295 .get_parent = ext2_get_parent,
296 .get_dentry = ext2_get_dentry,
299 static unsigned long get_sb_block(void **data)
301 unsigned long sb_block;
302 char *options = (char *) *data;
304 if (!options || strncmp(options, "sb=", 3) != 0)
305 return 1; /* Default location */
307 sb_block = simple_strtoul(options, &options, 0);
308 if (*options && *options != ',') {
309 printk("EXT2-fs: Invalid sb specification: %s\n",
315 *data = (void *) options;
320 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
321 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
322 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
323 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
324 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
325 Opt_usrquota, Opt_grpquota
328 static match_table_t tokens = {
329 {Opt_bsd_df, "bsddf"},
330 {Opt_minix_df, "minixdf"},
331 {Opt_grpid, "grpid"},
332 {Opt_grpid, "bsdgroups"},
333 {Opt_nogrpid, "nogrpid"},
334 {Opt_nogrpid, "sysvgroups"},
335 {Opt_resgid, "resgid=%u"},
336 {Opt_resuid, "resuid=%u"},
338 {Opt_err_cont, "errors=continue"},
339 {Opt_err_panic, "errors=panic"},
340 {Opt_err_ro, "errors=remount-ro"},
341 {Opt_nouid32, "nouid32"},
342 {Opt_nocheck, "check=none"},
343 {Opt_nocheck, "nocheck"},
344 {Opt_debug, "debug"},
345 {Opt_oldalloc, "oldalloc"},
346 {Opt_orlov, "orlov"},
348 {Opt_user_xattr, "user_xattr"},
349 {Opt_nouser_xattr, "nouser_xattr"},
351 {Opt_noacl, "noacl"},
353 {Opt_grpquota, "grpquota"},
354 {Opt_ignore, "noquota"},
355 {Opt_quota, "quota"},
356 {Opt_usrquota, "usrquota"},
360 static int parse_options (char * options,
361 struct ext2_sb_info *sbi)
364 substring_t args[MAX_OPT_ARGS];
370 while ((p = strsep (&options, ",")) != NULL) {
375 token = match_token(p, tokens, args);
378 clear_opt (sbi->s_mount_opt, MINIX_DF);
381 set_opt (sbi->s_mount_opt, MINIX_DF);
384 set_opt (sbi->s_mount_opt, GRPID);
387 clear_opt (sbi->s_mount_opt, GRPID);
390 if (match_int(&args[0], &option))
392 sbi->s_resuid = option;
395 if (match_int(&args[0], &option))
397 sbi->s_resgid = option;
400 /* handled by get_sb_block() instead of here */
401 /* *sb_block = match_int(&args[0]); */
404 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
405 clear_opt (sbi->s_mount_opt, ERRORS_RO);
406 set_opt (sbi->s_mount_opt, ERRORS_PANIC);
409 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
410 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
411 set_opt (sbi->s_mount_opt, ERRORS_RO);
414 clear_opt (sbi->s_mount_opt, ERRORS_RO);
415 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
416 set_opt (sbi->s_mount_opt, ERRORS_CONT);
419 set_opt (sbi->s_mount_opt, NO_UID32);
422 clear_opt (sbi->s_mount_opt, CHECK);
425 set_opt (sbi->s_mount_opt, DEBUG);
428 set_opt (sbi->s_mount_opt, OLDALLOC);
431 clear_opt (sbi->s_mount_opt, OLDALLOC);
434 set_opt (sbi->s_mount_opt, NOBH);
436 #ifdef CONFIG_EXT2_FS_XATTR
438 set_opt (sbi->s_mount_opt, XATTR_USER);
440 case Opt_nouser_xattr:
441 clear_opt (sbi->s_mount_opt, XATTR_USER);
445 case Opt_nouser_xattr:
446 printk("EXT2 (no)user_xattr options not supported\n");
449 #ifdef CONFIG_EXT2_FS_POSIX_ACL
451 set_opt(sbi->s_mount_opt, POSIX_ACL);
454 clear_opt(sbi->s_mount_opt, POSIX_ACL);
459 printk("EXT2 (no)acl options not supported\n");
463 #ifdef CONFIG_EXT2_FS_XIP
464 set_opt (sbi->s_mount_opt, XIP);
466 printk("EXT2 xip option not supported\n");
470 #if defined(CONFIG_QUOTA)
473 set_opt(sbi->s_mount_opt, USRQUOTA);
477 set_opt(sbi->s_mount_opt, GRPQUOTA);
484 "EXT2-fs: quota operations not supported.\n");
498 static int ext2_setup_super (struct super_block * sb,
499 struct ext2_super_block * es,
503 struct ext2_sb_info *sbi = EXT2_SB(sb);
505 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
506 printk ("EXT2-fs warning: revision level too high, "
507 "forcing read-only mode\n");
512 if (!(sbi->s_mount_state & EXT2_VALID_FS))
513 printk ("EXT2-fs warning: mounting unchecked fs, "
514 "running e2fsck is recommended\n");
515 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
516 printk ("EXT2-fs warning: mounting fs with errors, "
517 "running e2fsck is recommended\n");
518 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
519 le16_to_cpu(es->s_mnt_count) >=
520 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
521 printk ("EXT2-fs warning: maximal mount count reached, "
522 "running e2fsck is recommended\n");
523 else if (le32_to_cpu(es->s_checkinterval) &&
524 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
525 printk ("EXT2-fs warning: checktime reached, "
526 "running e2fsck is recommended\n");
527 if (!le16_to_cpu(es->s_max_mnt_count))
528 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
529 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
530 ext2_write_super(sb);
531 if (test_opt (sb, DEBUG))
532 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
533 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
534 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
537 EXT2_BLOCKS_PER_GROUP(sb),
538 EXT2_INODES_PER_GROUP(sb),
543 static int ext2_check_descriptors (struct super_block * sb)
547 struct ext2_sb_info *sbi = EXT2_SB(sb);
548 unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
549 unsigned long last_block;
550 struct ext2_group_desc * gdp = NULL;
552 ext2_debug ("Checking group descriptors");
554 for (i = 0; i < sbi->s_groups_count; i++)
556 if (i == sbi->s_groups_count - 1)
557 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
559 last_block = first_block +
560 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
562 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
563 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
564 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
565 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
567 ext2_error (sb, "ext2_check_descriptors",
568 "Block bitmap for group %d"
569 " not in group (block %lu)!",
570 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
573 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
574 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
576 ext2_error (sb, "ext2_check_descriptors",
577 "Inode bitmap for group %d"
578 " not in group (block %lu)!",
579 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
582 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
583 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group - 1 >
586 ext2_error (sb, "ext2_check_descriptors",
587 "Inode table for group %d"
588 " not in group (block %lu)!",
589 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
592 first_block += EXT2_BLOCKS_PER_GROUP(sb);
599 * Maximal file size. There is a direct, and {,double-,triple-}indirect
600 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
601 * We need to be 1 filesystem block less than the 2^32 sector limit.
603 static loff_t ext2_max_size(int bits)
605 loff_t res = EXT2_NDIR_BLOCKS;
606 /* This constant is calculated to be the largest file size for a
607 * dense, 4k-blocksize file such that the total number of
608 * sectors in the file, including data and all indirect blocks,
609 * does not exceed 2^32. */
610 const loff_t upper_limit = 0x1ff7fffd000LL;
612 res += 1LL << (bits-2);
613 res += 1LL << (2*(bits-2));
614 res += 1LL << (3*(bits-2));
616 if (res > upper_limit)
621 static unsigned long descriptor_loc(struct super_block *sb,
622 unsigned long logic_sb_block,
625 struct ext2_sb_info *sbi = EXT2_SB(sb);
626 unsigned long bg, first_data_block, first_meta_bg;
629 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
630 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
632 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
634 return (logic_sb_block + nr + 1);
635 bg = sbi->s_desc_per_block * nr;
636 if (ext2_bg_has_super(sb, bg))
638 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
641 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
643 struct buffer_head * bh;
644 struct ext2_sb_info * sbi;
645 struct ext2_super_block * es;
648 unsigned long sb_block = get_sb_block(&data);
649 unsigned long logic_sb_block;
650 unsigned long offset = 0;
651 unsigned long def_mount_opts;
652 int blocksize = BLOCK_SIZE;
658 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
664 * See what the current blocksize for the device is, and
665 * use that as the blocksize. Otherwise (or if the blocksize
666 * is smaller than the default) use the default.
667 * This is important for devices that have a hardware
668 * sectorsize that is larger than the default.
670 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
672 printk ("EXT2-fs: unable to set blocksize\n");
677 * If the superblock doesn't start on a hardware sector boundary,
678 * calculate the offset.
680 if (blocksize != BLOCK_SIZE) {
681 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
682 offset = (sb_block*BLOCK_SIZE) % blocksize;
684 logic_sb_block = sb_block;
687 if (!(bh = sb_bread(sb, logic_sb_block))) {
688 printk ("EXT2-fs: unable to read superblock\n");
692 * Note: s_es must be initialized as soon as possible because
693 * some ext2 macro-instructions depend on its value
695 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
697 sb->s_magic = le16_to_cpu(es->s_magic);
699 if (sb->s_magic != EXT2_SUPER_MAGIC)
702 /* Set defaults before we parse the mount options */
703 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
704 if (def_mount_opts & EXT2_DEFM_DEBUG)
705 set_opt(sbi->s_mount_opt, DEBUG);
706 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
707 set_opt(sbi->s_mount_opt, GRPID);
708 if (def_mount_opts & EXT2_DEFM_UID16)
709 set_opt(sbi->s_mount_opt, NO_UID32);
710 #ifdef CONFIG_EXT2_FS_XATTR
711 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
712 set_opt(sbi->s_mount_opt, XATTR_USER);
714 #ifdef CONFIG_EXT2_FS_POSIX_ACL
715 if (def_mount_opts & EXT2_DEFM_ACL)
716 set_opt(sbi->s_mount_opt, POSIX_ACL);
719 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
720 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
721 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO)
722 set_opt(sbi->s_mount_opt, ERRORS_RO);
724 set_opt(sbi->s_mount_opt, ERRORS_CONT);
726 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
727 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
729 if (!parse_options ((char *) data, sbi))
732 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
733 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
736 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
737 EXT2_MOUNT_XIP if not */
739 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
740 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
741 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
742 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
743 printk("EXT2-fs warning: feature flags set on rev 0 fs, "
744 "running e2fsck is recommended\n");
746 * Check feature flags regardless of the revision level, since we
747 * previously didn't change the revision level when setting the flags,
748 * so there is a chance incompat flags are set on a rev 0 filesystem.
750 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
752 printk("EXT2-fs: %s: couldn't mount because of "
753 "unsupported optional features (%x).\n",
754 sb->s_id, le32_to_cpu(features));
757 if (!(sb->s_flags & MS_RDONLY) &&
758 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
759 printk("EXT2-fs: %s: couldn't mount RDWR because of "
760 "unsupported optional features (%x).\n",
761 sb->s_id, le32_to_cpu(features));
765 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
767 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) ||
768 (sb->s_blocksize != blocksize))) {
770 printk("XIP: Unsupported blocksize\n");
774 /* If the blocksize doesn't match, re-read the thing.. */
775 if (sb->s_blocksize != blocksize) {
778 if (!sb_set_blocksize(sb, blocksize)) {
779 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
783 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
784 offset = (sb_block*BLOCK_SIZE) % blocksize;
785 bh = sb_bread(sb, logic_sb_block);
787 printk("EXT2-fs: Couldn't read superblock on "
791 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
793 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
794 printk ("EXT2-fs: Magic mismatch, very weird !\n");
799 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
801 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
802 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
803 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
805 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
806 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
807 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
808 (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
809 (sbi->s_inode_size > blocksize)) {
810 printk ("EXT2-fs: unsupported inode size: %d\n",
816 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
817 le32_to_cpu(es->s_log_frag_size);
818 if (sbi->s_frag_size == 0)
820 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
822 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
823 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
824 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
826 if (EXT2_INODE_SIZE(sb) == 0)
828 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
829 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
831 sbi->s_itb_per_group = sbi->s_inodes_per_group /
832 sbi->s_inodes_per_block;
833 sbi->s_desc_per_block = sb->s_blocksize /
834 sizeof (struct ext2_group_desc);
836 sbi->s_mount_state = le16_to_cpu(es->s_state);
837 sbi->s_addr_per_block_bits =
838 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
839 sbi->s_desc_per_block_bits =
840 ilog2 (EXT2_DESC_PER_BLOCK(sb));
842 if (sb->s_magic != EXT2_SUPER_MAGIC)
845 if (sb->s_blocksize != bh->b_size) {
847 printk ("VFS: Unsupported blocksize on dev "
852 if (sb->s_blocksize != sbi->s_frag_size) {
853 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
854 sbi->s_frag_size, sb->s_blocksize);
858 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
859 printk ("EXT2-fs: #blocks per group too big: %lu\n",
860 sbi->s_blocks_per_group);
863 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
864 printk ("EXT2-fs: #fragments per group too big: %lu\n",
865 sbi->s_frags_per_group);
868 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
869 printk ("EXT2-fs: #inodes per group too big: %lu\n",
870 sbi->s_inodes_per_group);
874 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
876 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
877 le32_to_cpu(es->s_first_data_block) - 1)
878 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
879 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
880 EXT2_DESC_PER_BLOCK(sb);
881 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
882 if (sbi->s_group_desc == NULL) {
883 printk ("EXT2-fs: not enough memory\n");
886 bgl_lock_init(&sbi->s_blockgroup_lock);
887 sbi->s_debts = kcalloc(sbi->s_groups_count, sizeof(*sbi->s_debts), GFP_KERNEL);
889 printk ("EXT2-fs: not enough memory\n");
890 goto failed_mount_group_desc;
892 for (i = 0; i < db_count; i++) {
893 block = descriptor_loc(sb, logic_sb_block, i);
894 sbi->s_group_desc[i] = sb_bread(sb, block);
895 if (!sbi->s_group_desc[i]) {
896 for (j = 0; j < i; j++)
897 brelse (sbi->s_group_desc[j]);
898 printk ("EXT2-fs: unable to read group descriptors\n");
899 goto failed_mount_group_desc;
902 if (!ext2_check_descriptors (sb)) {
903 printk ("EXT2-fs: group descriptors corrupted!\n");
906 sbi->s_gdb_count = db_count;
907 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
908 spin_lock_init(&sbi->s_next_gen_lock);
910 err = percpu_counter_init(&sbi->s_freeblocks_counter,
911 ext2_count_free_blocks(sb));
913 err = percpu_counter_init(&sbi->s_freeinodes_counter,
914 ext2_count_free_inodes(sb));
917 err = percpu_counter_init(&sbi->s_dirs_counter,
918 ext2_count_dirs(sb));
921 printk(KERN_ERR "EXT2-fs: insufficient memory\n");
925 * set up enough so that it can read an inode
927 sb->s_op = &ext2_sops;
928 sb->s_export_op = &ext2_export_ops;
929 sb->s_xattr = ext2_xattr_handlers;
930 root = iget(sb, EXT2_ROOT_INO);
931 sb->s_root = d_alloc_root(root);
934 printk(KERN_ERR "EXT2-fs: get root inode failed\n");
937 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
940 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
943 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
944 ext2_warning(sb, __FUNCTION__,
945 "mounting ext3 filesystem as ext2");
946 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
951 printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
955 percpu_counter_destroy(&sbi->s_freeblocks_counter);
956 percpu_counter_destroy(&sbi->s_freeinodes_counter);
957 percpu_counter_destroy(&sbi->s_dirs_counter);
959 for (i = 0; i < db_count; i++)
960 brelse(sbi->s_group_desc[i]);
961 failed_mount_group_desc:
962 kfree(sbi->s_group_desc);
967 sb->s_fs_info = NULL;
972 static void ext2_commit_super (struct super_block * sb,
973 struct ext2_super_block * es)
975 es->s_wtime = cpu_to_le32(get_seconds());
976 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
980 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
982 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
983 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
984 es->s_wtime = cpu_to_le32(get_seconds());
985 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
986 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
991 * In the second extended file system, it is not necessary to
992 * write the super block since we use a mapping of the
993 * disk super block in a buffer.
995 * However, this function is still used to set the fs valid
996 * flags to 0. We need to set this flag to 0 since the fs
997 * may have been checked while mounted and e2fsck may have
998 * set s_state to EXT2_VALID_FS after some corrections.
1001 void ext2_write_super (struct super_block * sb)
1003 struct ext2_super_block * es;
1005 if (!(sb->s_flags & MS_RDONLY)) {
1006 es = EXT2_SB(sb)->s_es;
1008 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) {
1009 ext2_debug ("setting valid to 0\n");
1010 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
1012 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1013 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1014 es->s_mtime = cpu_to_le32(get_seconds());
1015 ext2_sync_super(sb, es);
1017 ext2_commit_super (sb, es);
1023 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1025 struct ext2_sb_info * sbi = EXT2_SB(sb);
1026 struct ext2_super_block * es;
1027 unsigned long old_mount_opt = sbi->s_mount_opt;
1028 struct ext2_mount_options old_opts;
1029 unsigned long old_sb_flags;
1032 /* Store the old options */
1033 old_sb_flags = sb->s_flags;
1034 old_opts.s_mount_opt = sbi->s_mount_opt;
1035 old_opts.s_resuid = sbi->s_resuid;
1036 old_opts.s_resgid = sbi->s_resgid;
1039 * Allow the "check" option to be passed as a remount option.
1041 if (!parse_options (data, sbi)) {
1046 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1047 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1049 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
1050 EXT2_MOUNT_XIP if not */
1052 if ((ext2_use_xip(sb)) && (sb->s_blocksize != PAGE_SIZE)) {
1053 printk("XIP: Unsupported blocksize\n");
1059 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
1060 (old_mount_opt & EXT2_MOUNT_XIP)) &&
1061 invalidate_inodes(sb))
1062 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
1063 "xip remain in cache (no functional problem)");
1064 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1066 if (*flags & MS_RDONLY) {
1067 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1068 !(sbi->s_mount_state & EXT2_VALID_FS))
1071 * OK, we are remounting a valid rw partition rdonly, so set
1072 * the rdonly flag and then mark the partition as valid again.
1074 es->s_state = cpu_to_le16(sbi->s_mount_state);
1075 es->s_mtime = cpu_to_le32(get_seconds());
1077 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1078 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1080 printk("EXT2-fs: %s: couldn't remount RDWR because of "
1081 "unsupported optional features (%x).\n",
1082 sb->s_id, le32_to_cpu(ret));
1087 * Mounting a RDONLY partition read-write, so reread and
1088 * store the current valid flag. (It may have been changed
1089 * by e2fsck since we originally mounted the partition.)
1091 sbi->s_mount_state = le16_to_cpu(es->s_state);
1092 if (!ext2_setup_super (sb, es, 0))
1093 sb->s_flags &= ~MS_RDONLY;
1095 ext2_sync_super(sb, es);
1098 sbi->s_mount_opt = old_opts.s_mount_opt;
1099 sbi->s_resuid = old_opts.s_resuid;
1100 sbi->s_resgid = old_opts.s_resgid;
1101 sb->s_flags = old_sb_flags;
1105 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1107 struct super_block *sb = dentry->d_sb;
1108 struct ext2_sb_info *sbi = EXT2_SB(sb);
1109 struct ext2_super_block *es = sbi->s_es;
1112 if (test_opt (sb, MINIX_DF))
1113 sbi->s_overhead_last = 0;
1114 else if (sbi->s_blocks_last != le32_to_cpu(es->s_blocks_count)) {
1115 unsigned long i, overhead = 0;
1119 * Compute the overhead (FS structures). This is constant
1120 * for a given filesystem unless the number of block groups
1121 * changes so we cache the previous value until it does.
1125 * All of the blocks before first_data_block are
1128 overhead = le32_to_cpu(es->s_first_data_block);
1131 * Add the overhead attributed to the superblock and
1132 * block group descriptors. If the sparse superblocks
1133 * feature is turned on, then not all groups have this.
1135 for (i = 0; i < sbi->s_groups_count; i++)
1136 overhead += ext2_bg_has_super(sb, i) +
1137 ext2_bg_num_gdb(sb, i);
1140 * Every block group has an inode bitmap, a block
1141 * bitmap, and an inode table.
1143 overhead += (sbi->s_groups_count *
1144 (2 + sbi->s_itb_per_group));
1145 sbi->s_overhead_last = overhead;
1147 sbi->s_blocks_last = le32_to_cpu(es->s_blocks_count);
1150 buf->f_type = EXT2_SUPER_MAGIC;
1151 buf->f_bsize = sb->s_blocksize;
1152 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - sbi->s_overhead_last;
1153 buf->f_bfree = ext2_count_free_blocks(sb);
1154 es->s_free_blocks_count = cpu_to_le32(buf->f_bfree);
1155 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1156 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1158 buf->f_files = le32_to_cpu(es->s_inodes_count);
1159 buf->f_ffree = ext2_count_free_inodes(sb);
1160 es->s_free_inodes_count = cpu_to_le32(buf->f_ffree);
1161 buf->f_namelen = EXT2_NAME_LEN;
1162 fsid = le64_to_cpup((void *)es->s_uuid) ^
1163 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1164 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1165 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1169 static int ext2_get_sb(struct file_system_type *fs_type,
1170 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
1172 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt);
1177 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1178 * acquiring the locks... As quota files are never truncated and quota code
1179 * itself serializes the operations (and noone else should touch the files)
1180 * we don't have to be afraid of races */
1181 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1182 size_t len, loff_t off)
1184 struct inode *inode = sb_dqopt(sb)->files[type];
1185 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1187 int offset = off & (sb->s_blocksize - 1);
1190 struct buffer_head tmp_bh;
1191 struct buffer_head *bh;
1192 loff_t i_size = i_size_read(inode);
1196 if (off+len > i_size)
1199 while (toread > 0) {
1200 tocopy = sb->s_blocksize - offset < toread ?
1201 sb->s_blocksize - offset : toread;
1204 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1207 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1208 memset(data, 0, tocopy);
1210 bh = sb_bread(sb, tmp_bh.b_blocknr);
1213 memcpy(data, bh->b_data+offset, tocopy);
1224 /* Write to quotafile */
1225 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1226 const char *data, size_t len, loff_t off)
1228 struct inode *inode = sb_dqopt(sb)->files[type];
1229 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1231 int offset = off & (sb->s_blocksize - 1);
1233 size_t towrite = len;
1234 struct buffer_head tmp_bh;
1235 struct buffer_head *bh;
1237 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
1238 while (towrite > 0) {
1239 tocopy = sb->s_blocksize - offset < towrite ?
1240 sb->s_blocksize - offset : towrite;
1243 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1246 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1247 bh = sb_bread(sb, tmp_bh.b_blocknr);
1249 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1255 memcpy(bh->b_data+offset, data, tocopy);
1256 flush_dcache_page(bh->b_page);
1257 set_buffer_uptodate(bh);
1258 mark_buffer_dirty(bh);
1269 if (inode->i_size < off+len-towrite)
1270 i_size_write(inode, off+len-towrite);
1272 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1273 mark_inode_dirty(inode);
1274 mutex_unlock(&inode->i_mutex);
1275 return len - towrite;
1280 static struct file_system_type ext2_fs_type = {
1281 .owner = THIS_MODULE,
1283 .get_sb = ext2_get_sb,
1284 .kill_sb = kill_block_super,
1285 .fs_flags = FS_REQUIRES_DEV,
1288 static int __init init_ext2_fs(void)
1290 int err = init_ext2_xattr();
1293 err = init_inodecache();
1296 err = register_filesystem(&ext2_fs_type);
1301 destroy_inodecache();
1307 static void __exit exit_ext2_fs(void)
1309 unregister_filesystem(&ext2_fs_type);
1310 destroy_inodecache();
1314 module_init(init_ext2_fs)
1315 module_exit(exit_ext2_fs)