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|
181 if (ext2_inode_cachep == NULL)
186 static void destroy_inodecache(void)
188 if (kmem_cache_destroy(ext2_inode_cachep))
189 printk(KERN_INFO "ext2_inode_cache: not all structures were freed\n");
192 static void ext2_clear_inode(struct inode *inode)
194 #ifdef CONFIG_EXT2_FS_POSIX_ACL
195 struct ext2_inode_info *ei = EXT2_I(inode);
197 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) {
198 posix_acl_release(ei->i_acl);
199 ei->i_acl = EXT2_ACL_NOT_CACHED;
201 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) {
202 posix_acl_release(ei->i_default_acl);
203 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
208 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
210 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb);
212 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID)
213 seq_puts(seq, ",grpid");
215 #if defined(CONFIG_QUOTA)
216 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
217 seq_puts(seq, ",usrquota");
219 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
220 seq_puts(seq, ",grpquota");
223 #if defined(CONFIG_EXT2_FS_XIP)
224 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
225 seq_puts(seq, ",xip");
232 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
233 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
236 static struct super_operations ext2_sops = {
237 .alloc_inode = ext2_alloc_inode,
238 .destroy_inode = ext2_destroy_inode,
239 .read_inode = ext2_read_inode,
240 .write_inode = ext2_write_inode,
241 .put_inode = ext2_put_inode,
242 .delete_inode = ext2_delete_inode,
243 .put_super = ext2_put_super,
244 .write_super = ext2_write_super,
245 .statfs = ext2_statfs,
246 .remount_fs = ext2_remount,
247 .clear_inode = ext2_clear_inode,
248 .show_options = ext2_show_options,
250 .quota_read = ext2_quota_read,
251 .quota_write = ext2_quota_write,
255 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp)
258 unsigned long ino = objp[0];
259 __u32 generation = objp[1];
261 struct dentry *result;
263 if (ino != EXT2_ROOT_INO && ino < EXT2_FIRST_INO(sb))
264 return ERR_PTR(-ESTALE);
265 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
266 return ERR_PTR(-ESTALE);
268 /* iget isn't really right if the inode is currently unallocated!!
269 * ext2_read_inode currently does appropriate checks, but
270 * it might be "neater" to call ext2_get_inode first and check
271 * if the inode is valid.....
273 inode = iget(sb, ino);
275 return ERR_PTR(-ENOMEM);
276 if (is_bad_inode(inode)
277 || (generation && inode->i_generation != generation)
279 /* we didn't find the right inode.. */
281 return ERR_PTR(-ESTALE);
283 /* now to find a dentry.
284 * If possible, get a well-connected one
286 result = d_alloc_anon(inode);
289 return ERR_PTR(-ENOMEM);
295 /* Yes, most of these are left as NULL!!
296 * A NULL value implies the default, which works with ext2-like file
297 * systems, but can be improved upon.
298 * Currently only get_parent is required.
300 static struct export_operations ext2_export_ops = {
301 .get_parent = ext2_get_parent,
302 .get_dentry = ext2_get_dentry,
305 static unsigned long get_sb_block(void **data)
307 unsigned long sb_block;
308 char *options = (char *) *data;
310 if (!options || strncmp(options, "sb=", 3) != 0)
311 return 1; /* Default location */
313 sb_block = simple_strtoul(options, &options, 0);
314 if (*options && *options != ',') {
315 printk("EXT2-fs: Invalid sb specification: %s\n",
321 *data = (void *) options;
326 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
327 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
328 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
329 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
330 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
331 Opt_usrquota, Opt_grpquota, Opt_tagxid
334 static match_table_t tokens = {
335 {Opt_bsd_df, "bsddf"},
336 {Opt_minix_df, "minixdf"},
337 {Opt_grpid, "grpid"},
338 {Opt_grpid, "bsdgroups"},
339 {Opt_nogrpid, "nogrpid"},
340 {Opt_nogrpid, "sysvgroups"},
341 {Opt_resgid, "resgid=%u"},
342 {Opt_resuid, "resuid=%u"},
344 {Opt_err_cont, "errors=continue"},
345 {Opt_err_panic, "errors=panic"},
346 {Opt_err_ro, "errors=remount-ro"},
347 {Opt_nouid32, "nouid32"},
348 {Opt_nocheck, "check=none"},
349 {Opt_nocheck, "nocheck"},
350 {Opt_debug, "debug"},
351 {Opt_oldalloc, "oldalloc"},
352 {Opt_orlov, "orlov"},
354 {Opt_user_xattr, "user_xattr"},
355 {Opt_nouser_xattr, "nouser_xattr"},
357 {Opt_noacl, "noacl"},
359 {Opt_tagxid, "tagxid"},
360 {Opt_grpquota, "grpquota"},
361 {Opt_ignore, "noquota"},
362 {Opt_quota, "quota"},
363 {Opt_usrquota, "usrquota"},
367 static int parse_options (char * options,
368 struct ext2_sb_info *sbi)
371 substring_t args[MAX_OPT_ARGS];
372 unsigned long kind = EXT2_MOUNT_ERRORS_CONT;
378 while ((p = strsep (&options, ",")) != NULL) {
383 token = match_token(p, tokens, args);
386 clear_opt (sbi->s_mount_opt, MINIX_DF);
389 set_opt (sbi->s_mount_opt, MINIX_DF);
392 set_opt (sbi->s_mount_opt, GRPID);
395 clear_opt (sbi->s_mount_opt, GRPID);
398 if (match_int(&args[0], &option))
400 sbi->s_resuid = option;
403 if (match_int(&args[0], &option))
405 sbi->s_resgid = option;
408 /* handled by get_sb_block() instead of here */
409 /* *sb_block = match_int(&args[0]); */
412 kind = EXT2_MOUNT_ERRORS_PANIC;
415 kind = EXT2_MOUNT_ERRORS_RO;
418 kind = EXT2_MOUNT_ERRORS_CONT;
421 set_opt (sbi->s_mount_opt, NO_UID32);
423 #ifndef CONFIG_INOXID_NONE
425 set_opt (sbi->s_mount_opt, TAGXID);
429 clear_opt (sbi->s_mount_opt, CHECK);
432 set_opt (sbi->s_mount_opt, DEBUG);
435 set_opt (sbi->s_mount_opt, OLDALLOC);
438 clear_opt (sbi->s_mount_opt, OLDALLOC);
441 set_opt (sbi->s_mount_opt, NOBH);
443 #ifdef CONFIG_EXT2_FS_XATTR
445 set_opt (sbi->s_mount_opt, XATTR_USER);
447 case Opt_nouser_xattr:
448 clear_opt (sbi->s_mount_opt, XATTR_USER);
452 case Opt_nouser_xattr:
453 printk("EXT2 (no)user_xattr options not supported\n");
456 #ifdef CONFIG_EXT2_FS_POSIX_ACL
458 set_opt(sbi->s_mount_opt, POSIX_ACL);
461 clear_opt(sbi->s_mount_opt, POSIX_ACL);
466 printk("EXT2 (no)acl options not supported\n");
470 #ifdef CONFIG_EXT2_FS_XIP
471 set_opt (sbi->s_mount_opt, XIP);
473 printk("EXT2 xip option not supported\n");
477 #if defined(CONFIG_QUOTA)
480 set_opt(sbi->s_mount_opt, USRQUOTA);
484 set_opt(sbi->s_mount_opt, GRPQUOTA);
491 "EXT2-fs: quota operations not supported.\n");
502 sbi->s_mount_opt |= kind;
506 static int ext2_setup_super (struct super_block * sb,
507 struct ext2_super_block * es,
511 struct ext2_sb_info *sbi = EXT2_SB(sb);
513 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
514 printk ("EXT2-fs warning: revision level too high, "
515 "forcing read-only mode\n");
520 if (!(sbi->s_mount_state & EXT2_VALID_FS))
521 printk ("EXT2-fs warning: mounting unchecked fs, "
522 "running e2fsck is recommended\n");
523 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
524 printk ("EXT2-fs warning: mounting fs with errors, "
525 "running e2fsck is recommended\n");
526 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
527 le16_to_cpu(es->s_mnt_count) >=
528 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
529 printk ("EXT2-fs warning: maximal mount count reached, "
530 "running e2fsck is recommended\n");
531 else if (le32_to_cpu(es->s_checkinterval) &&
532 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
533 printk ("EXT2-fs warning: checktime reached, "
534 "running e2fsck is recommended\n");
535 if (!le16_to_cpu(es->s_max_mnt_count))
536 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
537 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
538 ext2_write_super(sb);
539 if (test_opt (sb, DEBUG))
540 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
541 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
542 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
545 EXT2_BLOCKS_PER_GROUP(sb),
546 EXT2_INODES_PER_GROUP(sb),
551 static int ext2_check_descriptors (struct super_block * sb)
555 struct ext2_sb_info *sbi = EXT2_SB(sb);
556 unsigned long block = le32_to_cpu(sbi->s_es->s_first_data_block);
557 struct ext2_group_desc * gdp = NULL;
559 ext2_debug ("Checking group descriptors");
561 for (i = 0; i < sbi->s_groups_count; i++)
563 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
564 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
565 if (le32_to_cpu(gdp->bg_block_bitmap) < block ||
566 le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
568 ext2_error (sb, "ext2_check_descriptors",
569 "Block bitmap for group %d"
570 " not in group (block %lu)!",
571 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
574 if (le32_to_cpu(gdp->bg_inode_bitmap) < block ||
575 le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
577 ext2_error (sb, "ext2_check_descriptors",
578 "Inode bitmap for group %d"
579 " not in group (block %lu)!",
580 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
583 if (le32_to_cpu(gdp->bg_inode_table) < block ||
584 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >=
585 block + EXT2_BLOCKS_PER_GROUP(sb))
587 ext2_error (sb, "ext2_check_descriptors",
588 "Inode table for group %d"
589 " not in group (block %lu)!",
590 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
593 block += EXT2_BLOCKS_PER_GROUP(sb);
599 #define log2(n) ffz(~(n))
602 * Maximal file size. There is a direct, and {,double-,triple-}indirect
603 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
604 * We need to be 1 filesystem block less than the 2^32 sector limit.
606 static loff_t ext2_max_size(int bits)
608 loff_t res = EXT2_NDIR_BLOCKS;
609 /* This constant is calculated to be the largest file size for a
610 * dense, 4k-blocksize file such that the total number of
611 * sectors in the file, including data and all indirect blocks,
612 * does not exceed 2^32. */
613 const loff_t upper_limit = 0x1ff7fffd000LL;
615 res += 1LL << (bits-2);
616 res += 1LL << (2*(bits-2));
617 res += 1LL << (3*(bits-2));
619 if (res > upper_limit)
624 static unsigned long descriptor_loc(struct super_block *sb,
625 unsigned long logic_sb_block,
628 struct ext2_sb_info *sbi = EXT2_SB(sb);
629 unsigned long bg, first_data_block, first_meta_bg;
632 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
633 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
635 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
637 return (logic_sb_block + nr + 1);
638 bg = sbi->s_desc_per_block * nr;
639 if (ext2_bg_has_super(sb, bg))
641 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
644 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
646 struct buffer_head * bh;
647 struct ext2_sb_info * sbi;
648 struct ext2_super_block * es;
651 unsigned long sb_block = get_sb_block(&data);
652 unsigned long logic_sb_block;
653 unsigned long offset = 0;
654 unsigned long def_mount_opts;
655 int blocksize = BLOCK_SIZE;
660 sbi = kmalloc(sizeof(*sbi), GFP_KERNEL);
664 memset(sbi, 0, sizeof(*sbi));
667 * See what the current blocksize for the device is, and
668 * use that as the blocksize. Otherwise (or if the blocksize
669 * is smaller than the default) use the default.
670 * This is important for devices that have a hardware
671 * sectorsize that is larger than the default.
673 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
675 printk ("EXT2-fs: unable to set blocksize\n");
680 * If the superblock doesn't start on a hardware sector boundary,
681 * calculate the offset.
683 if (blocksize != BLOCK_SIZE) {
684 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
685 offset = (sb_block*BLOCK_SIZE) % blocksize;
687 logic_sb_block = sb_block;
690 if (!(bh = sb_bread(sb, logic_sb_block))) {
691 printk ("EXT2-fs: unable to read superblock\n");
695 * Note: s_es must be initialized as soon as possible because
696 * some ext2 macro-instructions depend on its value
698 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
700 sb->s_magic = le16_to_cpu(es->s_magic);
702 if (sb->s_magic != EXT2_SUPER_MAGIC)
705 /* Set defaults before we parse the mount options */
706 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
707 if (def_mount_opts & EXT2_DEFM_DEBUG)
708 set_opt(sbi->s_mount_opt, DEBUG);
709 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
710 set_opt(sbi->s_mount_opt, GRPID);
711 if (def_mount_opts & EXT2_DEFM_UID16)
712 set_opt(sbi->s_mount_opt, NO_UID32);
713 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
714 set_opt(sbi->s_mount_opt, XATTR_USER);
715 if (def_mount_opts & EXT2_DEFM_ACL)
716 set_opt(sbi->s_mount_opt, POSIX_ACL);
718 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
719 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
720 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO)
721 set_opt(sbi->s_mount_opt, ERRORS_RO);
723 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
724 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
726 if (!parse_options ((char *) data, sbi))
729 if (EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_TAGXID)
730 sb->s_flags |= MS_TAGXID;
731 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
732 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
735 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
736 EXT2_MOUNT_XIP if not */
738 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
739 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
740 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
741 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
742 printk("EXT2-fs warning: feature flags set on rev 0 fs, "
743 "running e2fsck is recommended\n");
745 * Check feature flags regardless of the revision level, since we
746 * previously didn't change the revision level when setting the flags,
747 * so there is a chance incompat flags are set on a rev 0 filesystem.
749 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
751 printk("EXT2-fs: %s: couldn't mount because of "
752 "unsupported optional features (%x).\n",
753 sb->s_id, le32_to_cpu(features));
756 if (!(sb->s_flags & MS_RDONLY) &&
757 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
758 printk("EXT2-fs: %s: couldn't mount RDWR because of "
759 "unsupported optional features (%x).\n",
760 sb->s_id, le32_to_cpu(features));
764 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
766 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) ||
767 (sb->s_blocksize != blocksize))) {
769 printk("XIP: Unsupported blocksize\n");
773 /* If the blocksize doesn't match, re-read the thing.. */
774 if (sb->s_blocksize != blocksize) {
777 if (!sb_set_blocksize(sb, blocksize)) {
778 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
782 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
783 offset = (sb_block*BLOCK_SIZE) % blocksize;
784 bh = sb_bread(sb, logic_sb_block);
786 printk("EXT2-fs: Couldn't read superblock on "
790 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
792 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
793 printk ("EXT2-fs: Magic mismatch, very weird !\n");
798 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
800 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
801 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
802 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
804 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
805 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
806 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
807 (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
808 (sbi->s_inode_size > blocksize)) {
809 printk ("EXT2-fs: unsupported inode size: %d\n",
815 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
816 le32_to_cpu(es->s_log_frag_size);
817 if (sbi->s_frag_size == 0)
819 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
821 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
822 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
823 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
825 if (EXT2_INODE_SIZE(sb) == 0)
827 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
828 if (sbi->s_inodes_per_block == 0)
830 sbi->s_itb_per_group = sbi->s_inodes_per_group /
831 sbi->s_inodes_per_block;
832 sbi->s_desc_per_block = sb->s_blocksize /
833 sizeof (struct ext2_group_desc);
835 sbi->s_mount_state = le16_to_cpu(es->s_state);
836 sbi->s_addr_per_block_bits =
837 log2 (EXT2_ADDR_PER_BLOCK(sb));
838 sbi->s_desc_per_block_bits =
839 log2 (EXT2_DESC_PER_BLOCK(sb));
841 if (sb->s_magic != EXT2_SUPER_MAGIC)
844 if (sb->s_blocksize != bh->b_size) {
846 printk ("VFS: Unsupported blocksize on dev "
851 if (sb->s_blocksize != sbi->s_frag_size) {
852 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
853 sbi->s_frag_size, sb->s_blocksize);
857 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
858 printk ("EXT2-fs: #blocks per group too big: %lu\n",
859 sbi->s_blocks_per_group);
862 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
863 printk ("EXT2-fs: #fragments per group too big: %lu\n",
864 sbi->s_frags_per_group);
867 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
868 printk ("EXT2-fs: #inodes per group too big: %lu\n",
869 sbi->s_inodes_per_group);
873 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
875 sbi->s_groups_count = (le32_to_cpu(es->s_blocks_count) -
876 le32_to_cpu(es->s_first_data_block) +
877 EXT2_BLOCKS_PER_GROUP(sb) - 1) /
878 EXT2_BLOCKS_PER_GROUP(sb);
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 percpu_counter_init(&sbi->s_freeblocks_counter);
887 percpu_counter_init(&sbi->s_freeinodes_counter);
888 percpu_counter_init(&sbi->s_dirs_counter);
889 bgl_lock_init(&sbi->s_blockgroup_lock);
890 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts),
893 printk ("EXT2-fs: not enough memory\n");
894 goto failed_mount_group_desc;
896 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts));
897 for (i = 0; i < db_count; i++) {
898 block = descriptor_loc(sb, logic_sb_block, i);
899 sbi->s_group_desc[i] = sb_bread(sb, block);
900 if (!sbi->s_group_desc[i]) {
901 for (j = 0; j < i; j++)
902 brelse (sbi->s_group_desc[j]);
903 printk ("EXT2-fs: unable to read group descriptors\n");
904 goto failed_mount_group_desc;
907 if (!ext2_check_descriptors (sb)) {
908 printk ("EXT2-fs: group descriptors corrupted!\n");
912 sbi->s_gdb_count = db_count;
913 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
914 spin_lock_init(&sbi->s_next_gen_lock);
916 * set up enough so that it can read an inode
918 sb->s_op = &ext2_sops;
919 sb->s_export_op = &ext2_export_ops;
920 sb->s_xattr = ext2_xattr_handlers;
921 root = iget(sb, EXT2_ROOT_INO);
922 sb->s_root = d_alloc_root(root);
925 printk(KERN_ERR "EXT2-fs: get root inode failed\n");
928 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
931 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
934 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
935 ext2_warning(sb, __FUNCTION__,
936 "mounting ext3 filesystem as ext2");
937 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
938 percpu_counter_mod(&sbi->s_freeblocks_counter,
939 ext2_count_free_blocks(sb));
940 percpu_counter_mod(&sbi->s_freeinodes_counter,
941 ext2_count_free_inodes(sb));
942 percpu_counter_mod(&sbi->s_dirs_counter,
943 ext2_count_dirs(sb));
948 printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
953 for (i = 0; i < db_count; i++)
954 brelse(sbi->s_group_desc[i]);
955 failed_mount_group_desc:
956 kfree(sbi->s_group_desc);
961 sb->s_fs_info = NULL;
966 static void ext2_commit_super (struct super_block * sb,
967 struct ext2_super_block * es)
969 es->s_wtime = cpu_to_le32(get_seconds());
970 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
974 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
976 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
977 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
978 es->s_wtime = cpu_to_le32(get_seconds());
979 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
980 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
985 * In the second extended file system, it is not necessary to
986 * write the super block since we use a mapping of the
987 * disk super block in a buffer.
989 * However, this function is still used to set the fs valid
990 * flags to 0. We need to set this flag to 0 since the fs
991 * may have been checked while mounted and e2fsck may have
992 * set s_state to EXT2_VALID_FS after some corrections.
995 void ext2_write_super (struct super_block * sb)
997 struct ext2_super_block * es;
999 if (!(sb->s_flags & MS_RDONLY)) {
1000 es = EXT2_SB(sb)->s_es;
1002 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) {
1003 ext2_debug ("setting valid to 0\n");
1004 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
1006 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1007 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1008 es->s_mtime = cpu_to_le32(get_seconds());
1009 ext2_sync_super(sb, es);
1011 ext2_commit_super (sb, es);
1017 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1019 struct ext2_sb_info * sbi = EXT2_SB(sb);
1020 struct ext2_super_block * es;
1021 unsigned long old_mount_opt = sbi->s_mount_opt;
1022 struct ext2_mount_options old_opts;
1023 unsigned long old_sb_flags;
1026 /* Store the old options */
1027 old_sb_flags = sb->s_flags;
1028 old_opts.s_mount_opt = sbi->s_mount_opt;
1029 old_opts.s_resuid = sbi->s_resuid;
1030 old_opts.s_resgid = sbi->s_resgid;
1033 * Allow the "check" option to be passed as a remount option.
1035 if (!parse_options (data, sbi)) {
1040 if ((sbi->s_mount_opt & EXT2_MOUNT_TAGXID) &&
1041 !(sb->s_flags & MS_TAGXID)) {
1042 printk("EXT2-fs: %s: tagxid not permitted on remount.\n",
1047 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1048 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1051 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
1052 (old_mount_opt & EXT2_MOUNT_XIP)) &&
1053 invalidate_inodes(sb))
1054 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
1055 "xip remain in cache (no functional problem)");
1056 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1058 if (*flags & MS_RDONLY) {
1059 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1060 !(sbi->s_mount_state & EXT2_VALID_FS))
1063 * OK, we are remounting a valid rw partition rdonly, so set
1064 * the rdonly flag and then mark the partition as valid again.
1066 es->s_state = cpu_to_le16(sbi->s_mount_state);
1067 es->s_mtime = cpu_to_le32(get_seconds());
1069 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1070 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1072 printk("EXT2-fs: %s: couldn't remount RDWR because of "
1073 "unsupported optional features (%x).\n",
1074 sb->s_id, le32_to_cpu(ret));
1079 * Mounting a RDONLY partition read-write, so reread and
1080 * store the current valid flag. (It may have been changed
1081 * by e2fsck since we originally mounted the partition.)
1083 sbi->s_mount_state = le16_to_cpu(es->s_state);
1084 if (!ext2_setup_super (sb, es, 0))
1085 sb->s_flags &= ~MS_RDONLY;
1087 ext2_sync_super(sb, es);
1090 sbi->s_mount_opt = old_opts.s_mount_opt;
1091 sbi->s_resuid = old_opts.s_resuid;
1092 sbi->s_resgid = old_opts.s_resgid;
1093 sb->s_flags = old_sb_flags;
1097 static int ext2_statfs (struct super_block * sb, struct kstatfs * buf)
1099 struct ext2_sb_info *sbi = EXT2_SB(sb);
1100 unsigned long overhead;
1103 if (test_opt (sb, MINIX_DF))
1107 * Compute the overhead (FS structures)
1111 * All of the blocks before first_data_block are
1114 overhead = le32_to_cpu(sbi->s_es->s_first_data_block);
1117 * Add the overhead attributed to the superblock and
1118 * block group descriptors. If the sparse superblocks
1119 * feature is turned on, then not all groups have this.
1121 for (i = 0; i < sbi->s_groups_count; i++)
1122 overhead += ext2_bg_has_super(sb, i) +
1123 ext2_bg_num_gdb(sb, i);
1126 * Every block group has an inode bitmap, a block
1127 * bitmap, and an inode table.
1129 overhead += (sbi->s_groups_count *
1130 (2 + sbi->s_itb_per_group));
1133 buf->f_type = EXT2_SUPER_MAGIC;
1134 buf->f_bsize = sb->s_blocksize;
1135 buf->f_blocks = le32_to_cpu(sbi->s_es->s_blocks_count) - overhead;
1136 buf->f_bfree = ext2_count_free_blocks(sb);
1137 buf->f_bavail = buf->f_bfree - le32_to_cpu(sbi->s_es->s_r_blocks_count);
1138 if (buf->f_bfree < le32_to_cpu(sbi->s_es->s_r_blocks_count))
1140 buf->f_files = le32_to_cpu(sbi->s_es->s_inodes_count);
1141 buf->f_ffree = ext2_count_free_inodes (sb);
1142 buf->f_namelen = EXT2_NAME_LEN;
1146 static struct super_block *ext2_get_sb(struct file_system_type *fs_type,
1147 int flags, const char *dev_name, void *data)
1149 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1154 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1155 * acquiring the locks... As quota files are never truncated and quota code
1156 * itself serializes the operations (and noone else should touch the files)
1157 * we don't have to be afraid of races */
1158 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1159 size_t len, loff_t off)
1161 struct inode *inode = sb_dqopt(sb)->files[type];
1162 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1164 int offset = off & (sb->s_blocksize - 1);
1167 struct buffer_head tmp_bh;
1168 struct buffer_head *bh;
1169 loff_t i_size = i_size_read(inode);
1173 if (off+len > i_size)
1176 while (toread > 0) {
1177 tocopy = sb->s_blocksize - offset < toread ?
1178 sb->s_blocksize - offset : toread;
1181 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1184 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1185 memset(data, 0, tocopy);
1187 bh = sb_bread(sb, tmp_bh.b_blocknr);
1190 memcpy(data, bh->b_data+offset, tocopy);
1201 /* Write to quotafile */
1202 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1203 const char *data, size_t len, loff_t off)
1205 struct inode *inode = sb_dqopt(sb)->files[type];
1206 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1208 int offset = off & (sb->s_blocksize - 1);
1210 size_t towrite = len;
1211 struct buffer_head tmp_bh;
1212 struct buffer_head *bh;
1214 mutex_lock(&inode->i_mutex);
1215 while (towrite > 0) {
1216 tocopy = sb->s_blocksize - offset < towrite ?
1217 sb->s_blocksize - offset : towrite;
1220 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1223 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1224 bh = sb_bread(sb, tmp_bh.b_blocknr);
1226 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1232 memcpy(bh->b_data+offset, data, tocopy);
1233 flush_dcache_page(bh->b_page);
1234 set_buffer_uptodate(bh);
1235 mark_buffer_dirty(bh);
1246 if (inode->i_size < off+len-towrite)
1247 i_size_write(inode, off+len-towrite);
1249 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1250 mark_inode_dirty(inode);
1251 mutex_unlock(&inode->i_mutex);
1252 return len - towrite;
1257 static struct file_system_type ext2_fs_type = {
1258 .owner = THIS_MODULE,
1260 .get_sb = ext2_get_sb,
1261 .kill_sb = kill_block_super,
1262 .fs_flags = FS_REQUIRES_DEV,
1265 static int __init init_ext2_fs(void)
1267 int err = init_ext2_xattr();
1270 err = init_inodecache();
1273 err = register_filesystem(&ext2_fs_type);
1278 destroy_inodecache();
1284 static void __exit exit_ext2_fs(void)
1286 unregister_filesystem(&ext2_fs_type);
1287 destroy_inodecache();
1291 module_init(init_ext2_fs)
1292 module_exit(exit_ext2_fs)