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/config.h>
20 #include <linux/module.h>
21 #include <linux/string.h>
23 #include <linux/slab.h>
24 #include <linux/init.h>
25 #include <linux/blkdev.h>
26 #include <linux/parser.h>
27 #include <linux/random.h>
28 #include <linux/buffer_head.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 super_block * sb, 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 kmem_cache_t * 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, SLAB_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, kmem_cache_t * cachep, unsigned long flags)
162 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
164 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
165 SLAB_CTOR_CONSTRUCTOR) {
166 rwlock_init(&ei->i_meta_lock);
167 #ifdef CONFIG_EXT2_FS_XATTR
168 init_rwsem(&ei->xattr_sem);
170 inode_init_once(&ei->vfs_inode);
174 static int init_inodecache(void)
176 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
177 sizeof(struct ext2_inode_info),
178 0, SLAB_RECLAIM_ACCOUNT,
180 if (ext2_inode_cachep == NULL)
185 static void destroy_inodecache(void)
187 if (kmem_cache_destroy(ext2_inode_cachep))
188 printk(KERN_INFO "ext2_inode_cache: not all structures were freed\n");
191 static void ext2_clear_inode(struct inode *inode)
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;
207 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
209 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb);
211 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID)
212 seq_puts(seq, ",grpid");
214 seq_puts(seq, ",nogrpid");
216 #if defined(CONFIG_QUOTA)
217 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
218 seq_puts(seq, ",usrquota");
220 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
221 seq_puts(seq, ",grpquota");
224 #if defined(CONFIG_EXT2_FS_XIP)
225 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
226 seq_puts(seq, ",xip");
233 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
234 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
237 static struct super_operations ext2_sops = {
238 .alloc_inode = ext2_alloc_inode,
239 .destroy_inode = ext2_destroy_inode,
240 .read_inode = ext2_read_inode,
241 .write_inode = ext2_write_inode,
242 .put_inode = ext2_put_inode,
243 .delete_inode = ext2_delete_inode,
244 .put_super = ext2_put_super,
245 .write_super = ext2_write_super,
246 .statfs = ext2_statfs,
247 .remount_fs = ext2_remount,
248 .clear_inode = ext2_clear_inode,
249 .show_options = ext2_show_options,
251 .quota_read = ext2_quota_read,
252 .quota_write = ext2_quota_write,
256 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp)
259 unsigned long ino = objp[0];
260 __u32 generation = objp[1];
262 struct dentry *result;
264 if (ino != EXT2_ROOT_INO && ino < EXT2_FIRST_INO(sb))
265 return ERR_PTR(-ESTALE);
266 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
267 return ERR_PTR(-ESTALE);
269 /* iget isn't really right if the inode is currently unallocated!!
270 * ext2_read_inode currently does appropriate checks, but
271 * it might be "neater" to call ext2_get_inode first and check
272 * if the inode is valid.....
274 inode = iget(sb, ino);
276 return ERR_PTR(-ENOMEM);
277 if (is_bad_inode(inode)
278 || (generation && inode->i_generation != generation)
280 /* we didn't find the right inode.. */
282 return ERR_PTR(-ESTALE);
284 /* now to find a dentry.
285 * If possible, get a well-connected one
287 result = d_alloc_anon(inode);
290 return ERR_PTR(-ENOMEM);
296 /* Yes, most of these are left as NULL!!
297 * A NULL value implies the default, which works with ext2-like file
298 * systems, but can be improved upon.
299 * Currently only get_parent is required.
301 struct dentry *ext2_get_parent(struct dentry *child);
302 static struct export_operations ext2_export_ops = {
303 .get_parent = ext2_get_parent,
304 .get_dentry = ext2_get_dentry,
307 static unsigned long get_sb_block(void **data)
309 unsigned long sb_block;
310 char *options = (char *) *data;
312 if (!options || strncmp(options, "sb=", 3) != 0)
313 return 1; /* Default location */
315 sb_block = simple_strtoul(options, &options, 0);
316 if (*options && *options != ',') {
317 printk("EXT2-fs: Invalid sb specification: %s\n",
323 *data = (void *) options;
328 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
329 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
330 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
331 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
332 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
333 Opt_usrquota, Opt_grpquota, Opt_tagxid
336 static match_table_t tokens = {
337 {Opt_bsd_df, "bsddf"},
338 {Opt_minix_df, "minixdf"},
339 {Opt_grpid, "grpid"},
340 {Opt_grpid, "bsdgroups"},
341 {Opt_nogrpid, "nogrpid"},
342 {Opt_nogrpid, "sysvgroups"},
343 {Opt_resgid, "resgid=%u"},
344 {Opt_resuid, "resuid=%u"},
346 {Opt_err_cont, "errors=continue"},
347 {Opt_err_panic, "errors=panic"},
348 {Opt_err_ro, "errors=remount-ro"},
349 {Opt_nouid32, "nouid32"},
350 {Opt_nocheck, "check=none"},
351 {Opt_nocheck, "nocheck"},
352 {Opt_debug, "debug"},
353 {Opt_oldalloc, "oldalloc"},
354 {Opt_orlov, "orlov"},
356 {Opt_user_xattr, "user_xattr"},
357 {Opt_nouser_xattr, "nouser_xattr"},
359 {Opt_noacl, "noacl"},
361 {Opt_tagxid, "tagxid"},
362 {Opt_grpquota, "grpquota"},
363 {Opt_ignore, "noquota"},
364 {Opt_quota, "quota"},
365 {Opt_usrquota, "usrquota"},
369 static int parse_options (char * options,
370 struct ext2_sb_info *sbi)
373 substring_t args[MAX_OPT_ARGS];
374 unsigned long kind = EXT2_MOUNT_ERRORS_CONT;
380 while ((p = strsep (&options, ",")) != NULL) {
385 token = match_token(p, tokens, args);
388 clear_opt (sbi->s_mount_opt, MINIX_DF);
391 set_opt (sbi->s_mount_opt, MINIX_DF);
394 set_opt (sbi->s_mount_opt, GRPID);
397 clear_opt (sbi->s_mount_opt, GRPID);
400 if (match_int(&args[0], &option))
402 sbi->s_resuid = option;
405 if (match_int(&args[0], &option))
407 sbi->s_resgid = option;
410 /* handled by get_sb_block() instead of here */
411 /* *sb_block = match_int(&args[0]); */
414 kind = EXT2_MOUNT_ERRORS_PANIC;
417 kind = EXT2_MOUNT_ERRORS_RO;
420 kind = EXT2_MOUNT_ERRORS_CONT;
423 set_opt (sbi->s_mount_opt, NO_UID32);
425 #ifndef CONFIG_INOXID_NONE
427 set_opt (sbi->s_mount_opt, TAGXID);
431 clear_opt (sbi->s_mount_opt, CHECK);
434 set_opt (sbi->s_mount_opt, DEBUG);
437 set_opt (sbi->s_mount_opt, OLDALLOC);
440 clear_opt (sbi->s_mount_opt, OLDALLOC);
443 set_opt (sbi->s_mount_opt, NOBH);
445 #ifdef CONFIG_EXT2_FS_XATTR
447 set_opt (sbi->s_mount_opt, XATTR_USER);
449 case Opt_nouser_xattr:
450 clear_opt (sbi->s_mount_opt, XATTR_USER);
454 case Opt_nouser_xattr:
455 printk("EXT2 (no)user_xattr options not supported\n");
458 #ifdef CONFIG_EXT2_FS_POSIX_ACL
460 set_opt(sbi->s_mount_opt, POSIX_ACL);
463 clear_opt(sbi->s_mount_opt, POSIX_ACL);
468 printk("EXT2 (no)acl options not supported\n");
472 #ifdef CONFIG_EXT2_FS_XIP
473 set_opt (sbi->s_mount_opt, XIP);
475 printk("EXT2 xip option not supported\n");
479 #if defined(CONFIG_QUOTA)
482 set_opt(sbi->s_mount_opt, USRQUOTA);
486 set_opt(sbi->s_mount_opt, GRPQUOTA);
493 "EXT2-fs: quota operations not supported.\n");
504 sbi->s_mount_opt |= kind;
508 static int ext2_setup_super (struct super_block * sb,
509 struct ext2_super_block * es,
513 struct ext2_sb_info *sbi = EXT2_SB(sb);
515 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
516 printk ("EXT2-fs warning: revision level too high, "
517 "forcing read-only mode\n");
522 if (!(sbi->s_mount_state & EXT2_VALID_FS))
523 printk ("EXT2-fs warning: mounting unchecked fs, "
524 "running e2fsck is recommended\n");
525 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
526 printk ("EXT2-fs warning: mounting fs with errors, "
527 "running e2fsck is recommended\n");
528 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
529 le16_to_cpu(es->s_mnt_count) >=
530 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
531 printk ("EXT2-fs warning: maximal mount count reached, "
532 "running e2fsck is recommended\n");
533 else if (le32_to_cpu(es->s_checkinterval) &&
534 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
535 printk ("EXT2-fs warning: checktime reached, "
536 "running e2fsck is recommended\n");
537 if (!le16_to_cpu(es->s_max_mnt_count))
538 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
539 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
540 ext2_write_super(sb);
541 if (test_opt (sb, DEBUG))
542 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
543 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
544 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
547 EXT2_BLOCKS_PER_GROUP(sb),
548 EXT2_INODES_PER_GROUP(sb),
553 static int ext2_check_descriptors (struct super_block * sb)
557 struct ext2_sb_info *sbi = EXT2_SB(sb);
558 unsigned long block = le32_to_cpu(sbi->s_es->s_first_data_block);
559 struct ext2_group_desc * gdp = NULL;
561 ext2_debug ("Checking group descriptors");
563 for (i = 0; i < sbi->s_groups_count; i++)
565 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
566 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
567 if (le32_to_cpu(gdp->bg_block_bitmap) < block ||
568 le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
570 ext2_error (sb, "ext2_check_descriptors",
571 "Block bitmap for group %d"
572 " not in group (block %lu)!",
573 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
576 if (le32_to_cpu(gdp->bg_inode_bitmap) < block ||
577 le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
579 ext2_error (sb, "ext2_check_descriptors",
580 "Inode bitmap for group %d"
581 " not in group (block %lu)!",
582 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
585 if (le32_to_cpu(gdp->bg_inode_table) < block ||
586 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >=
587 block + EXT2_BLOCKS_PER_GROUP(sb))
589 ext2_error (sb, "ext2_check_descriptors",
590 "Inode table for group %d"
591 " not in group (block %lu)!",
592 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
595 block += EXT2_BLOCKS_PER_GROUP(sb);
601 #define log2(n) ffz(~(n))
604 * Maximal file size. There is a direct, and {,double-,triple-}indirect
605 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
606 * We need to be 1 filesystem block less than the 2^32 sector limit.
608 static loff_t ext2_max_size(int bits)
610 loff_t res = EXT2_NDIR_BLOCKS;
611 /* This constant is calculated to be the largest file size for a
612 * dense, 4k-blocksize file such that the total number of
613 * sectors in the file, including data and all indirect blocks,
614 * does not exceed 2^32. */
615 const loff_t upper_limit = 0x1ff7fffd000LL;
617 res += 1LL << (bits-2);
618 res += 1LL << (2*(bits-2));
619 res += 1LL << (3*(bits-2));
621 if (res > upper_limit)
626 static unsigned long descriptor_loc(struct super_block *sb,
627 unsigned long logic_sb_block,
630 struct ext2_sb_info *sbi = EXT2_SB(sb);
631 unsigned long bg, first_data_block, first_meta_bg;
634 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
635 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
637 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
639 return (logic_sb_block + nr + 1);
640 bg = sbi->s_desc_per_block * nr;
641 if (ext2_bg_has_super(sb, bg))
643 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
646 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
648 struct buffer_head * bh;
649 struct ext2_sb_info * sbi;
650 struct ext2_super_block * es;
653 unsigned long sb_block = get_sb_block(&data);
654 unsigned long logic_sb_block;
655 unsigned long offset = 0;
656 unsigned long def_mount_opts;
657 int blocksize = BLOCK_SIZE;
662 sbi = kmalloc(sizeof(*sbi), GFP_KERNEL);
666 memset(sbi, 0, sizeof(*sbi));
669 * See what the current blocksize for the device is, and
670 * use that as the blocksize. Otherwise (or if the blocksize
671 * is smaller than the default) use the default.
672 * This is important for devices that have a hardware
673 * sectorsize that is larger than the default.
675 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
677 printk ("EXT2-fs: unable to set blocksize\n");
682 * If the superblock doesn't start on a hardware sector boundary,
683 * calculate the offset.
685 if (blocksize != BLOCK_SIZE) {
686 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
687 offset = (sb_block*BLOCK_SIZE) % blocksize;
689 logic_sb_block = sb_block;
692 if (!(bh = sb_bread(sb, logic_sb_block))) {
693 printk ("EXT2-fs: unable to read superblock\n");
697 * Note: s_es must be initialized as soon as possible because
698 * some ext2 macro-instructions depend on its value
700 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
702 sb->s_magic = le16_to_cpu(es->s_magic);
704 if (sb->s_magic != EXT2_SUPER_MAGIC)
707 /* Set defaults before we parse the mount options */
708 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
709 if (def_mount_opts & EXT2_DEFM_DEBUG)
710 set_opt(sbi->s_mount_opt, DEBUG);
711 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
712 set_opt(sbi->s_mount_opt, GRPID);
713 if (def_mount_opts & EXT2_DEFM_UID16)
714 set_opt(sbi->s_mount_opt, NO_UID32);
715 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
716 set_opt(sbi->s_mount_opt, XATTR_USER);
717 if (def_mount_opts & EXT2_DEFM_ACL)
718 set_opt(sbi->s_mount_opt, POSIX_ACL);
720 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
721 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
722 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO)
723 set_opt(sbi->s_mount_opt, ERRORS_RO);
725 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
726 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
728 if (!parse_options ((char *) data, sbi))
731 if (EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_TAGXID)
732 sb->s_flags |= MS_TAGXID;
733 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
734 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
737 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
738 EXT2_MOUNT_XIP if not */
740 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
741 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
742 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
743 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
744 printk("EXT2-fs warning: feature flags set on rev 0 fs, "
745 "running e2fsck is recommended\n");
747 * Check feature flags regardless of the revision level, since we
748 * previously didn't change the revision level when setting the flags,
749 * so there is a chance incompat flags are set on a rev 0 filesystem.
751 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
753 printk("EXT2-fs: %s: couldn't mount because of "
754 "unsupported optional features (%x).\n",
755 sb->s_id, le32_to_cpu(features));
758 if (!(sb->s_flags & MS_RDONLY) &&
759 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
760 printk("EXT2-fs: %s: couldn't mount RDWR because of "
761 "unsupported optional features (%x).\n",
762 sb->s_id, le32_to_cpu(features));
766 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
768 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) ||
769 (sb->s_blocksize != blocksize))) {
771 printk("XIP: Unsupported blocksize\n");
775 /* If the blocksize doesn't match, re-read the thing.. */
776 if (sb->s_blocksize != blocksize) {
779 if (!sb_set_blocksize(sb, blocksize)) {
780 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
784 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
785 offset = (sb_block*BLOCK_SIZE) % blocksize;
786 bh = sb_bread(sb, logic_sb_block);
788 printk("EXT2-fs: Couldn't read superblock on "
792 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
794 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
795 printk ("EXT2-fs: Magic mismatch, very weird !\n");
800 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
802 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
803 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
804 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
806 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
807 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
808 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
809 (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
810 (sbi->s_inode_size > blocksize)) {
811 printk ("EXT2-fs: unsupported inode size: %d\n",
817 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
818 le32_to_cpu(es->s_log_frag_size);
819 if (sbi->s_frag_size == 0)
821 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
823 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
824 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
825 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
827 if (EXT2_INODE_SIZE(sb) == 0)
829 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
830 if (sbi->s_inodes_per_block == 0)
832 sbi->s_itb_per_group = sbi->s_inodes_per_group /
833 sbi->s_inodes_per_block;
834 sbi->s_desc_per_block = sb->s_blocksize /
835 sizeof (struct ext2_group_desc);
837 sbi->s_mount_state = le16_to_cpu(es->s_state);
838 sbi->s_addr_per_block_bits =
839 log2 (EXT2_ADDR_PER_BLOCK(sb));
840 sbi->s_desc_per_block_bits =
841 log2 (EXT2_DESC_PER_BLOCK(sb));
843 if (sb->s_magic != EXT2_SUPER_MAGIC)
846 if (sb->s_blocksize != bh->b_size) {
848 printk ("VFS: Unsupported blocksize on dev "
853 if (sb->s_blocksize != sbi->s_frag_size) {
854 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
855 sbi->s_frag_size, sb->s_blocksize);
859 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
860 printk ("EXT2-fs: #blocks per group too big: %lu\n",
861 sbi->s_blocks_per_group);
864 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
865 printk ("EXT2-fs: #fragments per group too big: %lu\n",
866 sbi->s_frags_per_group);
869 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
870 printk ("EXT2-fs: #inodes per group too big: %lu\n",
871 sbi->s_inodes_per_group);
875 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
877 sbi->s_groups_count = (le32_to_cpu(es->s_blocks_count) -
878 le32_to_cpu(es->s_first_data_block) +
879 EXT2_BLOCKS_PER_GROUP(sb) - 1) /
880 EXT2_BLOCKS_PER_GROUP(sb);
881 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
882 EXT2_DESC_PER_BLOCK(sb);
883 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
884 if (sbi->s_group_desc == NULL) {
885 printk ("EXT2-fs: not enough memory\n");
888 percpu_counter_init(&sbi->s_freeblocks_counter);
889 percpu_counter_init(&sbi->s_freeinodes_counter);
890 percpu_counter_init(&sbi->s_dirs_counter);
891 bgl_lock_init(&sbi->s_blockgroup_lock);
892 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts),
895 printk ("EXT2-fs: not enough memory\n");
896 goto failed_mount_group_desc;
898 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts));
899 for (i = 0; i < db_count; i++) {
900 block = descriptor_loc(sb, logic_sb_block, i);
901 sbi->s_group_desc[i] = sb_bread(sb, block);
902 if (!sbi->s_group_desc[i]) {
903 for (j = 0; j < i; j++)
904 brelse (sbi->s_group_desc[j]);
905 printk ("EXT2-fs: unable to read group descriptors\n");
906 goto failed_mount_group_desc;
909 if (!ext2_check_descriptors (sb)) {
910 printk ("EXT2-fs: group descriptors corrupted!\n");
914 sbi->s_gdb_count = db_count;
915 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
916 spin_lock_init(&sbi->s_next_gen_lock);
918 * set up enough so that it can read an inode
920 sb->s_op = &ext2_sops;
921 sb->s_export_op = &ext2_export_ops;
922 sb->s_xattr = ext2_xattr_handlers;
923 root = iget(sb, EXT2_ROOT_INO);
924 sb->s_root = d_alloc_root(root);
927 printk(KERN_ERR "EXT2-fs: get root inode failed\n");
930 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
933 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
936 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
937 ext2_warning(sb, __FUNCTION__,
938 "mounting ext3 filesystem as ext2");
939 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
940 percpu_counter_mod(&sbi->s_freeblocks_counter,
941 ext2_count_free_blocks(sb));
942 percpu_counter_mod(&sbi->s_freeinodes_counter,
943 ext2_count_free_inodes(sb));
944 percpu_counter_mod(&sbi->s_dirs_counter,
945 ext2_count_dirs(sb));
950 printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
955 for (i = 0; i < db_count; i++)
956 brelse(sbi->s_group_desc[i]);
957 failed_mount_group_desc:
958 kfree(sbi->s_group_desc);
963 sb->s_fs_info = NULL;
968 static void ext2_commit_super (struct super_block * sb,
969 struct ext2_super_block * es)
971 es->s_wtime = cpu_to_le32(get_seconds());
972 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
976 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
978 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
979 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
980 es->s_wtime = cpu_to_le32(get_seconds());
981 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
982 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
987 * In the second extended file system, it is not necessary to
988 * write the super block since we use a mapping of the
989 * disk super block in a buffer.
991 * However, this function is still used to set the fs valid
992 * flags to 0. We need to set this flag to 0 since the fs
993 * may have been checked while mounted and e2fsck may have
994 * set s_state to EXT2_VALID_FS after some corrections.
997 void ext2_write_super (struct super_block * sb)
999 struct ext2_super_block * es;
1001 if (!(sb->s_flags & MS_RDONLY)) {
1002 es = EXT2_SB(sb)->s_es;
1004 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) {
1005 ext2_debug ("setting valid to 0\n");
1006 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
1008 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1009 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1010 es->s_mtime = cpu_to_le32(get_seconds());
1011 ext2_sync_super(sb, es);
1013 ext2_commit_super (sb, es);
1019 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1021 struct ext2_sb_info * sbi = EXT2_SB(sb);
1022 struct ext2_super_block * es;
1023 unsigned long old_mount_opt = sbi->s_mount_opt;
1024 struct ext2_mount_options old_opts;
1025 unsigned long old_sb_flags;
1028 /* Store the old options */
1029 old_sb_flags = sb->s_flags;
1030 old_opts.s_mount_opt = sbi->s_mount_opt;
1031 old_opts.s_resuid = sbi->s_resuid;
1032 old_opts.s_resgid = sbi->s_resgid;
1035 * Allow the "check" option to be passed as a remount option.
1037 if (!parse_options (data, sbi)) {
1042 if ((sbi->s_mount_opt & EXT2_MOUNT_TAGXID) &&
1043 !(sb->s_flags & MS_TAGXID)) {
1044 printk("EXT2-fs: %s: tagxid not permitted on remount.\n",
1049 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1050 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1053 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
1054 (old_mount_opt & EXT2_MOUNT_XIP)) &&
1055 invalidate_inodes(sb))
1056 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
1057 "xip remain in cache (no functional problem)");
1058 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1060 if (*flags & MS_RDONLY) {
1061 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1062 !(sbi->s_mount_state & EXT2_VALID_FS))
1065 * OK, we are remounting a valid rw partition rdonly, so set
1066 * the rdonly flag and then mark the partition as valid again.
1068 es->s_state = cpu_to_le16(sbi->s_mount_state);
1069 es->s_mtime = cpu_to_le32(get_seconds());
1071 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1072 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1074 printk("EXT2-fs: %s: couldn't remount RDWR because of "
1075 "unsupported optional features (%x).\n",
1076 sb->s_id, le32_to_cpu(ret));
1081 * Mounting a RDONLY partition read-write, so reread and
1082 * store the current valid flag. (It may have been changed
1083 * by e2fsck since we originally mounted the partition.)
1085 sbi->s_mount_state = le16_to_cpu(es->s_state);
1086 if (!ext2_setup_super (sb, es, 0))
1087 sb->s_flags &= ~MS_RDONLY;
1089 ext2_sync_super(sb, es);
1092 sbi->s_mount_opt = old_opts.s_mount_opt;
1093 sbi->s_resuid = old_opts.s_resuid;
1094 sbi->s_resgid = old_opts.s_resgid;
1095 sb->s_flags = old_sb_flags;
1099 static int ext2_statfs (struct super_block * sb, struct kstatfs * buf)
1101 struct ext2_sb_info *sbi = EXT2_SB(sb);
1102 unsigned long overhead;
1105 if (test_opt (sb, MINIX_DF))
1109 * Compute the overhead (FS structures)
1113 * All of the blocks before first_data_block are
1116 overhead = le32_to_cpu(sbi->s_es->s_first_data_block);
1119 * Add the overhead attributed to the superblock and
1120 * block group descriptors. If the sparse superblocks
1121 * feature is turned on, then not all groups have this.
1123 for (i = 0; i < sbi->s_groups_count; i++)
1124 overhead += ext2_bg_has_super(sb, i) +
1125 ext2_bg_num_gdb(sb, i);
1128 * Every block group has an inode bitmap, a block
1129 * bitmap, and an inode table.
1131 overhead += (sbi->s_groups_count *
1132 (2 + sbi->s_itb_per_group));
1135 buf->f_type = EXT2_SUPER_MAGIC;
1136 buf->f_bsize = sb->s_blocksize;
1137 buf->f_blocks = le32_to_cpu(sbi->s_es->s_blocks_count) - overhead;
1138 buf->f_bfree = ext2_count_free_blocks(sb);
1139 buf->f_bavail = buf->f_bfree - le32_to_cpu(sbi->s_es->s_r_blocks_count);
1140 if (buf->f_bfree < le32_to_cpu(sbi->s_es->s_r_blocks_count))
1142 buf->f_files = le32_to_cpu(sbi->s_es->s_inodes_count);
1143 buf->f_ffree = ext2_count_free_inodes (sb);
1144 buf->f_namelen = EXT2_NAME_LEN;
1148 static struct super_block *ext2_get_sb(struct file_system_type *fs_type,
1149 int flags, const char *dev_name, void *data)
1151 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1156 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1157 * acquiring the locks... As quota files are never truncated and quota code
1158 * itself serializes the operations (and noone else should touch the files)
1159 * we don't have to be afraid of races */
1160 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1161 size_t len, loff_t off)
1163 struct inode *inode = sb_dqopt(sb)->files[type];
1164 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1166 int offset = off & (sb->s_blocksize - 1);
1169 struct buffer_head tmp_bh;
1170 struct buffer_head *bh;
1171 loff_t i_size = i_size_read(inode);
1175 if (off+len > i_size)
1178 while (toread > 0) {
1179 tocopy = sb->s_blocksize - offset < toread ?
1180 sb->s_blocksize - offset : toread;
1183 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1186 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1187 memset(data, 0, tocopy);
1189 bh = sb_bread(sb, tmp_bh.b_blocknr);
1192 memcpy(data, bh->b_data+offset, tocopy);
1203 /* Write to quotafile */
1204 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1205 const char *data, size_t len, loff_t off)
1207 struct inode *inode = sb_dqopt(sb)->files[type];
1208 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1210 int offset = off & (sb->s_blocksize - 1);
1212 size_t towrite = len;
1213 struct buffer_head tmp_bh;
1214 struct buffer_head *bh;
1216 mutex_lock(&inode->i_mutex);
1217 while (towrite > 0) {
1218 tocopy = sb->s_blocksize - offset < towrite ?
1219 sb->s_blocksize - offset : towrite;
1222 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1225 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1226 bh = sb_bread(sb, tmp_bh.b_blocknr);
1228 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1234 memcpy(bh->b_data+offset, data, tocopy);
1235 flush_dcache_page(bh->b_page);
1236 set_buffer_uptodate(bh);
1237 mark_buffer_dirty(bh);
1248 if (inode->i_size < off+len-towrite)
1249 i_size_write(inode, off+len-towrite);
1251 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1252 mark_inode_dirty(inode);
1253 mutex_unlock(&inode->i_mutex);
1254 return len - towrite;
1259 static struct file_system_type ext2_fs_type = {
1260 .owner = THIS_MODULE,
1262 .get_sb = ext2_get_sb,
1263 .kill_sb = kill_block_super,
1264 .fs_flags = FS_REQUIRES_DEV,
1267 static int __init init_ext2_fs(void)
1269 int err = init_ext2_xattr();
1272 err = init_inodecache();
1275 err = register_filesystem(&ext2_fs_type);
1280 destroy_inodecache();
1286 static void __exit exit_ext2_fs(void)
1288 unregister_filesystem(&ext2_fs_type);
1289 destroy_inodecache();
1293 module_init(init_ext2_fs)
1294 module_exit(exit_ext2_fs)