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/smp_lock.h>
29 #include <linux/vfs.h>
30 #include <linux/seq_file.h>
31 #include <linux/mount.h>
32 #include <asm/uaccess.h>
38 static void ext2_sync_super(struct super_block *sb,
39 struct ext2_super_block *es);
40 static int ext2_remount (struct super_block * sb, int * flags, char * data);
41 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf);
43 void ext2_error (struct super_block * sb, const char * function,
44 const char * fmt, ...)
47 struct ext2_sb_info *sbi = EXT2_SB(sb);
48 struct ext2_super_block *es = sbi->s_es;
50 if (!(sb->s_flags & MS_RDONLY)) {
51 sbi->s_mount_state |= EXT2_ERROR_FS;
53 cpu_to_le16(le16_to_cpu(es->s_state) | EXT2_ERROR_FS);
54 ext2_sync_super(sb, es);
58 printk(KERN_CRIT "EXT2-fs error (device %s): %s: ",sb->s_id, function);
63 if (test_opt(sb, ERRORS_PANIC))
64 panic("EXT2-fs panic from previous error\n");
65 if (test_opt(sb, ERRORS_RO)) {
66 printk("Remounting filesystem read-only\n");
67 sb->s_flags |= MS_RDONLY;
71 void ext2_warning (struct super_block * sb, const char * function,
72 const char * fmt, ...)
77 printk(KERN_WARNING "EXT2-fs warning (device %s): %s: ",
84 void ext2_update_dynamic_rev(struct super_block *sb)
86 struct ext2_super_block *es = EXT2_SB(sb)->s_es;
88 if (le32_to_cpu(es->s_rev_level) > EXT2_GOOD_OLD_REV)
91 ext2_warning(sb, __FUNCTION__,
92 "updating to rev %d because of new feature flag, "
93 "running e2fsck is recommended",
96 es->s_first_ino = cpu_to_le32(EXT2_GOOD_OLD_FIRST_INO);
97 es->s_inode_size = cpu_to_le16(EXT2_GOOD_OLD_INODE_SIZE);
98 es->s_rev_level = cpu_to_le32(EXT2_DYNAMIC_REV);
99 /* leave es->s_feature_*compat flags alone */
100 /* es->s_uuid will be set by e2fsck if empty */
103 * The rest of the superblock fields should be zero, and if not it
104 * means they are likely already in use, so leave them alone. We
105 * can leave it up to e2fsck to clean up any inconsistencies there.
109 static void ext2_put_super (struct super_block * sb)
113 struct ext2_sb_info *sbi = EXT2_SB(sb);
115 ext2_xattr_put_super(sb);
116 if (!(sb->s_flags & MS_RDONLY)) {
117 struct ext2_super_block *es = sbi->s_es;
119 es->s_state = cpu_to_le16(sbi->s_mount_state);
120 ext2_sync_super(sb, es);
122 db_count = sbi->s_gdb_count;
123 for (i = 0; i < db_count; i++)
124 if (sbi->s_group_desc[i])
125 brelse (sbi->s_group_desc[i]);
126 kfree(sbi->s_group_desc);
128 percpu_counter_destroy(&sbi->s_freeblocks_counter);
129 percpu_counter_destroy(&sbi->s_freeinodes_counter);
130 percpu_counter_destroy(&sbi->s_dirs_counter);
132 sb->s_fs_info = NULL;
138 static struct kmem_cache * ext2_inode_cachep;
140 static struct inode *ext2_alloc_inode(struct super_block *sb)
142 struct ext2_inode_info *ei;
143 ei = (struct ext2_inode_info *)kmem_cache_alloc(ext2_inode_cachep, GFP_KERNEL);
146 #ifdef CONFIG_EXT2_FS_POSIX_ACL
147 ei->i_acl = EXT2_ACL_NOT_CACHED;
148 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
150 ei->vfs_inode.i_version = 1;
151 return &ei->vfs_inode;
154 static void ext2_destroy_inode(struct inode *inode)
156 kmem_cache_free(ext2_inode_cachep, EXT2_I(inode));
159 static void init_once(void * foo, struct kmem_cache * cachep, unsigned long flags)
161 struct ext2_inode_info *ei = (struct ext2_inode_info *) foo;
163 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
164 SLAB_CTOR_CONSTRUCTOR) {
165 rwlock_init(&ei->i_meta_lock);
166 #ifdef CONFIG_EXT2_FS_XATTR
167 init_rwsem(&ei->xattr_sem);
169 inode_init_once(&ei->vfs_inode);
173 static int init_inodecache(void)
175 ext2_inode_cachep = kmem_cache_create("ext2_inode_cache",
176 sizeof(struct ext2_inode_info),
177 0, (SLAB_RECLAIM_ACCOUNT|
180 if (ext2_inode_cachep == NULL)
185 static void destroy_inodecache(void)
187 kmem_cache_destroy(ext2_inode_cachep);
190 static void ext2_clear_inode(struct inode *inode)
192 #ifdef CONFIG_EXT2_FS_POSIX_ACL
193 struct ext2_inode_info *ei = EXT2_I(inode);
195 if (ei->i_acl && ei->i_acl != EXT2_ACL_NOT_CACHED) {
196 posix_acl_release(ei->i_acl);
197 ei->i_acl = EXT2_ACL_NOT_CACHED;
199 if (ei->i_default_acl && ei->i_default_acl != EXT2_ACL_NOT_CACHED) {
200 posix_acl_release(ei->i_default_acl);
201 ei->i_default_acl = EXT2_ACL_NOT_CACHED;
206 static int ext2_show_options(struct seq_file *seq, struct vfsmount *vfs)
208 struct ext2_sb_info *sbi = EXT2_SB(vfs->mnt_sb);
210 if (sbi->s_mount_opt & EXT2_MOUNT_GRPID)
211 seq_puts(seq, ",grpid");
213 #if defined(CONFIG_QUOTA)
214 if (sbi->s_mount_opt & EXT2_MOUNT_USRQUOTA)
215 seq_puts(seq, ",usrquota");
217 if (sbi->s_mount_opt & EXT2_MOUNT_GRPQUOTA)
218 seq_puts(seq, ",grpquota");
221 #if defined(CONFIG_EXT2_FS_XIP)
222 if (sbi->s_mount_opt & EXT2_MOUNT_XIP)
223 seq_puts(seq, ",xip");
230 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data, size_t len, loff_t off);
231 static ssize_t ext2_quota_write(struct super_block *sb, int type, const char *data, size_t len, loff_t off);
234 static struct super_operations ext2_sops = {
235 .alloc_inode = ext2_alloc_inode,
236 .destroy_inode = ext2_destroy_inode,
237 .read_inode = ext2_read_inode,
238 .write_inode = ext2_write_inode,
239 .put_inode = ext2_put_inode,
240 .delete_inode = ext2_delete_inode,
241 .put_super = ext2_put_super,
242 .write_super = ext2_write_super,
243 .statfs = ext2_statfs,
244 .remount_fs = ext2_remount,
245 .clear_inode = ext2_clear_inode,
246 .show_options = ext2_show_options,
248 .quota_read = ext2_quota_read,
249 .quota_write = ext2_quota_write,
253 static struct dentry *ext2_get_dentry(struct super_block *sb, void *vobjp)
256 unsigned long ino = objp[0];
257 __u32 generation = objp[1];
259 struct dentry *result;
261 if (ino < EXT2_FIRST_INO(sb) && ino != EXT2_ROOT_INO)
262 return ERR_PTR(-ESTALE);
263 if (ino > le32_to_cpu(EXT2_SB(sb)->s_es->s_inodes_count))
264 return ERR_PTR(-ESTALE);
266 /* iget isn't really right if the inode is currently unallocated!!
267 * ext2_read_inode currently does appropriate checks, but
268 * it might be "neater" to call ext2_get_inode first and check
269 * if the inode is valid.....
271 inode = iget(sb, ino);
273 return ERR_PTR(-ENOMEM);
274 if (is_bad_inode(inode) ||
275 (generation && inode->i_generation != generation)) {
276 /* we didn't find the right inode.. */
278 return ERR_PTR(-ESTALE);
280 /* now to find a dentry.
281 * If possible, get a well-connected one
283 result = d_alloc_anon(inode);
286 return ERR_PTR(-ENOMEM);
291 /* Yes, most of these are left as NULL!!
292 * A NULL value implies the default, which works with ext2-like file
293 * systems, but can be improved upon.
294 * Currently only get_parent is required.
296 static struct export_operations ext2_export_ops = {
297 .get_parent = ext2_get_parent,
298 .get_dentry = ext2_get_dentry,
301 static unsigned long get_sb_block(void **data)
303 unsigned long sb_block;
304 char *options = (char *) *data;
306 if (!options || strncmp(options, "sb=", 3) != 0)
307 return 1; /* Default location */
309 sb_block = simple_strtoul(options, &options, 0);
310 if (*options && *options != ',') {
311 printk("EXT2-fs: Invalid sb specification: %s\n",
317 *data = (void *) options;
322 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
323 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
324 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
325 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
326 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
327 Opt_usrquota, Opt_grpquota, Opt_tag, Opt_notag, Opt_tagid
330 static match_table_t tokens = {
331 {Opt_bsd_df, "bsddf"},
332 {Opt_minix_df, "minixdf"},
333 {Opt_grpid, "grpid"},
334 {Opt_grpid, "bsdgroups"},
335 {Opt_nogrpid, "nogrpid"},
336 {Opt_nogrpid, "sysvgroups"},
337 {Opt_resgid, "resgid=%u"},
338 {Opt_resuid, "resuid=%u"},
340 {Opt_err_cont, "errors=continue"},
341 {Opt_err_panic, "errors=panic"},
342 {Opt_err_ro, "errors=remount-ro"},
343 {Opt_nouid32, "nouid32"},
344 {Opt_nocheck, "check=none"},
345 {Opt_nocheck, "nocheck"},
346 {Opt_debug, "debug"},
347 {Opt_oldalloc, "oldalloc"},
348 {Opt_orlov, "orlov"},
350 {Opt_user_xattr, "user_xattr"},
351 {Opt_nouser_xattr, "nouser_xattr"},
353 {Opt_noacl, "noacl"},
356 {Opt_notag, "notag"},
357 {Opt_tagid, "tagid=%u"},
359 {Opt_grpquota, "grpquota"},
360 {Opt_ignore, "noquota"},
361 {Opt_quota, "quota"},
362 {Opt_usrquota, "usrquota"},
366 static int parse_options (char * options,
367 struct ext2_sb_info *sbi)
370 substring_t args[MAX_OPT_ARGS];
376 while ((p = strsep (&options, ",")) != NULL) {
381 token = match_token(p, tokens, args);
384 clear_opt (sbi->s_mount_opt, MINIX_DF);
387 set_opt (sbi->s_mount_opt, MINIX_DF);
390 set_opt (sbi->s_mount_opt, GRPID);
393 clear_opt (sbi->s_mount_opt, GRPID);
396 if (match_int(&args[0], &option))
398 sbi->s_resuid = option;
401 if (match_int(&args[0], &option))
403 sbi->s_resgid = option;
406 /* handled by get_sb_block() instead of here */
407 /* *sb_block = match_int(&args[0]); */
410 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
411 clear_opt (sbi->s_mount_opt, ERRORS_RO);
412 set_opt (sbi->s_mount_opt, ERRORS_PANIC);
415 clear_opt (sbi->s_mount_opt, ERRORS_CONT);
416 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
417 set_opt (sbi->s_mount_opt, ERRORS_RO);
420 clear_opt (sbi->s_mount_opt, ERRORS_RO);
421 clear_opt (sbi->s_mount_opt, ERRORS_PANIC);
422 set_opt (sbi->s_mount_opt, ERRORS_CONT);
425 set_opt (sbi->s_mount_opt, NO_UID32);
427 #ifndef CONFIG_TAGGING_NONE
429 set_opt (sbi->s_mount_opt, TAGGED);
432 clear_opt (sbi->s_mount_opt, TAGGED);
435 #ifdef CONFIG_PROPAGATE
438 set_opt (sbi->s_mount_opt, TAGGED);
442 clear_opt (sbi->s_mount_opt, CHECK);
445 set_opt (sbi->s_mount_opt, DEBUG);
448 set_opt (sbi->s_mount_opt, OLDALLOC);
451 clear_opt (sbi->s_mount_opt, OLDALLOC);
454 set_opt (sbi->s_mount_opt, NOBH);
456 #ifdef CONFIG_EXT2_FS_XATTR
458 set_opt (sbi->s_mount_opt, XATTR_USER);
460 case Opt_nouser_xattr:
461 clear_opt (sbi->s_mount_opt, XATTR_USER);
465 case Opt_nouser_xattr:
466 printk("EXT2 (no)user_xattr options not supported\n");
469 #ifdef CONFIG_EXT2_FS_POSIX_ACL
471 set_opt(sbi->s_mount_opt, POSIX_ACL);
474 clear_opt(sbi->s_mount_opt, POSIX_ACL);
479 printk("EXT2 (no)acl options not supported\n");
483 #ifdef CONFIG_EXT2_FS_XIP
484 set_opt (sbi->s_mount_opt, XIP);
486 printk("EXT2 xip option not supported\n");
490 #if defined(CONFIG_QUOTA)
493 set_opt(sbi->s_mount_opt, USRQUOTA);
497 set_opt(sbi->s_mount_opt, GRPQUOTA);
504 "EXT2-fs: quota operations not supported.\n");
518 static int ext2_setup_super (struct super_block * sb,
519 struct ext2_super_block * es,
523 struct ext2_sb_info *sbi = EXT2_SB(sb);
525 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
526 printk ("EXT2-fs warning: revision level too high, "
527 "forcing read-only mode\n");
532 if (!(sbi->s_mount_state & EXT2_VALID_FS))
533 printk ("EXT2-fs warning: mounting unchecked fs, "
534 "running e2fsck is recommended\n");
535 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
536 printk ("EXT2-fs warning: mounting fs with errors, "
537 "running e2fsck is recommended\n");
538 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
539 le16_to_cpu(es->s_mnt_count) >=
540 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
541 printk ("EXT2-fs warning: maximal mount count reached, "
542 "running e2fsck is recommended\n");
543 else if (le32_to_cpu(es->s_checkinterval) &&
544 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
545 printk ("EXT2-fs warning: checktime reached, "
546 "running e2fsck is recommended\n");
547 if (!le16_to_cpu(es->s_max_mnt_count))
548 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
549 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
550 ext2_write_super(sb);
551 if (test_opt (sb, DEBUG))
552 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
553 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
554 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
557 EXT2_BLOCKS_PER_GROUP(sb),
558 EXT2_INODES_PER_GROUP(sb),
563 static int ext2_check_descriptors (struct super_block * sb)
567 struct ext2_sb_info *sbi = EXT2_SB(sb);
568 unsigned long first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
569 unsigned long last_block;
570 struct ext2_group_desc * gdp = NULL;
572 ext2_debug ("Checking group descriptors");
574 for (i = 0; i < sbi->s_groups_count; i++)
576 if (i == sbi->s_groups_count - 1)
577 last_block = le32_to_cpu(sbi->s_es->s_blocks_count) - 1;
579 last_block = first_block +
580 (EXT2_BLOCKS_PER_GROUP(sb) - 1);
582 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
583 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
584 if (le32_to_cpu(gdp->bg_block_bitmap) < first_block ||
585 le32_to_cpu(gdp->bg_block_bitmap) > last_block)
587 ext2_error (sb, "ext2_check_descriptors",
588 "Block bitmap for group %d"
589 " not in group (block %lu)!",
590 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
593 if (le32_to_cpu(gdp->bg_inode_bitmap) < first_block ||
594 le32_to_cpu(gdp->bg_inode_bitmap) > last_block)
596 ext2_error (sb, "ext2_check_descriptors",
597 "Inode bitmap for group %d"
598 " not in group (block %lu)!",
599 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
602 if (le32_to_cpu(gdp->bg_inode_table) < first_block ||
603 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >
606 ext2_error (sb, "ext2_check_descriptors",
607 "Inode table for group %d"
608 " not in group (block %lu)!",
609 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
612 first_block += EXT2_BLOCKS_PER_GROUP(sb);
619 * Maximal file size. There is a direct, and {,double-,triple-}indirect
620 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
621 * We need to be 1 filesystem block less than the 2^32 sector limit.
623 static loff_t ext2_max_size(int bits)
625 loff_t res = EXT2_NDIR_BLOCKS;
626 /* This constant is calculated to be the largest file size for a
627 * dense, 4k-blocksize file such that the total number of
628 * sectors in the file, including data and all indirect blocks,
629 * does not exceed 2^32. */
630 const loff_t upper_limit = 0x1ff7fffd000LL;
632 res += 1LL << (bits-2);
633 res += 1LL << (2*(bits-2));
634 res += 1LL << (3*(bits-2));
636 if (res > upper_limit)
641 static unsigned long descriptor_loc(struct super_block *sb,
642 unsigned long logic_sb_block,
645 struct ext2_sb_info *sbi = EXT2_SB(sb);
646 unsigned long bg, first_data_block, first_meta_bg;
649 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
650 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
652 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
654 return (logic_sb_block + nr + 1);
655 bg = sbi->s_desc_per_block * nr;
656 if (ext2_bg_has_super(sb, bg))
658 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
661 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
663 struct buffer_head * bh;
664 struct ext2_sb_info * sbi;
665 struct ext2_super_block * es;
668 unsigned long sb_block = get_sb_block(&data);
669 unsigned long logic_sb_block;
670 unsigned long offset = 0;
671 unsigned long def_mount_opts;
672 int blocksize = BLOCK_SIZE;
677 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
683 * See what the current blocksize for the device is, and
684 * use that as the blocksize. Otherwise (or if the blocksize
685 * is smaller than the default) use the default.
686 * This is important for devices that have a hardware
687 * sectorsize that is larger than the default.
689 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
691 printk ("EXT2-fs: unable to set blocksize\n");
696 * If the superblock doesn't start on a hardware sector boundary,
697 * calculate the offset.
699 if (blocksize != BLOCK_SIZE) {
700 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
701 offset = (sb_block*BLOCK_SIZE) % blocksize;
703 logic_sb_block = sb_block;
706 if (!(bh = sb_bread(sb, logic_sb_block))) {
707 printk ("EXT2-fs: unable to read superblock\n");
711 * Note: s_es must be initialized as soon as possible because
712 * some ext2 macro-instructions depend on its value
714 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
716 sb->s_magic = le16_to_cpu(es->s_magic);
718 if (sb->s_magic != EXT2_SUPER_MAGIC)
721 /* Set defaults before we parse the mount options */
722 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
723 if (def_mount_opts & EXT2_DEFM_DEBUG)
724 set_opt(sbi->s_mount_opt, DEBUG);
725 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
726 set_opt(sbi->s_mount_opt, GRPID);
727 if (def_mount_opts & EXT2_DEFM_UID16)
728 set_opt(sbi->s_mount_opt, NO_UID32);
729 #ifdef CONFIG_EXT2_FS_XATTR
730 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
731 set_opt(sbi->s_mount_opt, XATTR_USER);
733 #ifdef CONFIG_EXT2_FS_POSIX_ACL
734 if (def_mount_opts & EXT2_DEFM_ACL)
735 set_opt(sbi->s_mount_opt, POSIX_ACL);
738 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
739 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
740 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO)
741 set_opt(sbi->s_mount_opt, ERRORS_RO);
743 set_opt(sbi->s_mount_opt, ERRORS_CONT);
745 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
746 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
748 if (!parse_options ((char *) data, sbi))
751 if (EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_TAGGED)
752 sb->s_flags |= MS_TAGGED;
753 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
754 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
757 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
758 EXT2_MOUNT_XIP if not */
760 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
761 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
762 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
763 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
764 printk("EXT2-fs warning: feature flags set on rev 0 fs, "
765 "running e2fsck is recommended\n");
767 * Check feature flags regardless of the revision level, since we
768 * previously didn't change the revision level when setting the flags,
769 * so there is a chance incompat flags are set on a rev 0 filesystem.
771 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
773 printk("EXT2-fs: %s: couldn't mount because of "
774 "unsupported optional features (%x).\n",
775 sb->s_id, le32_to_cpu(features));
778 if (!(sb->s_flags & MS_RDONLY) &&
779 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
780 printk("EXT2-fs: %s: couldn't mount RDWR because of "
781 "unsupported optional features (%x).\n",
782 sb->s_id, le32_to_cpu(features));
786 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
788 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) ||
789 (sb->s_blocksize != blocksize))) {
791 printk("XIP: Unsupported blocksize\n");
795 /* If the blocksize doesn't match, re-read the thing.. */
796 if (sb->s_blocksize != blocksize) {
799 if (!sb_set_blocksize(sb, blocksize)) {
800 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
804 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
805 offset = (sb_block*BLOCK_SIZE) % blocksize;
806 bh = sb_bread(sb, logic_sb_block);
808 printk("EXT2-fs: Couldn't read superblock on "
812 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
814 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
815 printk ("EXT2-fs: Magic mismatch, very weird !\n");
820 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
822 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
823 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
824 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
826 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
827 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
828 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
829 (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
830 (sbi->s_inode_size > blocksize)) {
831 printk ("EXT2-fs: unsupported inode size: %d\n",
837 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
838 le32_to_cpu(es->s_log_frag_size);
839 if (sbi->s_frag_size == 0)
841 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
843 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
844 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
845 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
847 if (EXT2_INODE_SIZE(sb) == 0)
849 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
850 if (sbi->s_inodes_per_block == 0 || sbi->s_inodes_per_group == 0)
852 sbi->s_itb_per_group = sbi->s_inodes_per_group /
853 sbi->s_inodes_per_block;
854 sbi->s_desc_per_block = sb->s_blocksize /
855 sizeof (struct ext2_group_desc);
857 sbi->s_mount_state = le16_to_cpu(es->s_state);
858 sbi->s_addr_per_block_bits =
859 ilog2 (EXT2_ADDR_PER_BLOCK(sb));
860 sbi->s_desc_per_block_bits =
861 ilog2 (EXT2_DESC_PER_BLOCK(sb));
863 if (sb->s_magic != EXT2_SUPER_MAGIC)
866 if (sb->s_blocksize != bh->b_size) {
868 printk ("VFS: Unsupported blocksize on dev "
873 if (sb->s_blocksize != sbi->s_frag_size) {
874 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
875 sbi->s_frag_size, sb->s_blocksize);
879 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
880 printk ("EXT2-fs: #blocks per group too big: %lu\n",
881 sbi->s_blocks_per_group);
884 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
885 printk ("EXT2-fs: #fragments per group too big: %lu\n",
886 sbi->s_frags_per_group);
889 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
890 printk ("EXT2-fs: #inodes per group too big: %lu\n",
891 sbi->s_inodes_per_group);
895 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
897 sbi->s_groups_count = ((le32_to_cpu(es->s_blocks_count) -
898 le32_to_cpu(es->s_first_data_block) - 1)
899 / EXT2_BLOCKS_PER_GROUP(sb)) + 1;
900 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
901 EXT2_DESC_PER_BLOCK(sb);
902 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
903 if (sbi->s_group_desc == NULL) {
904 printk ("EXT2-fs: not enough memory\n");
907 bgl_lock_init(&sbi->s_blockgroup_lock);
908 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts),
911 printk ("EXT2-fs: not enough memory\n");
912 goto failed_mount_group_desc;
914 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts));
915 for (i = 0; i < db_count; i++) {
916 block = descriptor_loc(sb, logic_sb_block, i);
917 sbi->s_group_desc[i] = sb_bread(sb, block);
918 if (!sbi->s_group_desc[i]) {
919 for (j = 0; j < i; j++)
920 brelse (sbi->s_group_desc[j]);
921 printk ("EXT2-fs: unable to read group descriptors\n");
922 goto failed_mount_group_desc;
925 if (!ext2_check_descriptors (sb)) {
926 printk ("EXT2-fs: group descriptors corrupted!\n");
929 sbi->s_gdb_count = db_count;
930 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
931 spin_lock_init(&sbi->s_next_gen_lock);
933 percpu_counter_init(&sbi->s_freeblocks_counter,
934 ext2_count_free_blocks(sb));
935 percpu_counter_init(&sbi->s_freeinodes_counter,
936 ext2_count_free_inodes(sb));
937 percpu_counter_init(&sbi->s_dirs_counter,
938 ext2_count_dirs(sb));
940 * set up enough so that it can read an inode
942 sb->s_op = &ext2_sops;
943 sb->s_export_op = &ext2_export_ops;
944 sb->s_xattr = ext2_xattr_handlers;
945 root = iget(sb, EXT2_ROOT_INO);
946 sb->s_root = d_alloc_root(root);
949 printk(KERN_ERR "EXT2-fs: get root inode failed\n");
952 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
955 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
958 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
959 ext2_warning(sb, __FUNCTION__,
960 "mounting ext3 filesystem as ext2");
961 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
966 printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
970 percpu_counter_destroy(&sbi->s_freeblocks_counter);
971 percpu_counter_destroy(&sbi->s_freeinodes_counter);
972 percpu_counter_destroy(&sbi->s_dirs_counter);
974 for (i = 0; i < db_count; i++)
975 brelse(sbi->s_group_desc[i]);
976 failed_mount_group_desc:
977 kfree(sbi->s_group_desc);
982 sb->s_fs_info = NULL;
987 static void ext2_commit_super (struct super_block * sb,
988 struct ext2_super_block * es)
990 es->s_wtime = cpu_to_le32(get_seconds());
991 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
995 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
997 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
998 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
999 es->s_wtime = cpu_to_le32(get_seconds());
1000 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
1001 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
1006 * In the second extended file system, it is not necessary to
1007 * write the super block since we use a mapping of the
1008 * disk super block in a buffer.
1010 * However, this function is still used to set the fs valid
1011 * flags to 0. We need to set this flag to 0 since the fs
1012 * may have been checked while mounted and e2fsck may have
1013 * set s_state to EXT2_VALID_FS after some corrections.
1016 void ext2_write_super (struct super_block * sb)
1018 struct ext2_super_block * es;
1020 if (!(sb->s_flags & MS_RDONLY)) {
1021 es = EXT2_SB(sb)->s_es;
1023 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) {
1024 ext2_debug ("setting valid to 0\n");
1025 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
1027 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
1028 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
1029 es->s_mtime = cpu_to_le32(get_seconds());
1030 ext2_sync_super(sb, es);
1032 ext2_commit_super (sb, es);
1038 static int ext2_remount (struct super_block * sb, int * flags, char * data)
1040 struct ext2_sb_info * sbi = EXT2_SB(sb);
1041 struct ext2_super_block * es;
1042 unsigned long old_mount_opt = sbi->s_mount_opt;
1043 struct ext2_mount_options old_opts;
1044 unsigned long old_sb_flags;
1047 /* Store the old options */
1048 old_sb_flags = sb->s_flags;
1049 old_opts.s_mount_opt = sbi->s_mount_opt;
1050 old_opts.s_resuid = sbi->s_resuid;
1051 old_opts.s_resgid = sbi->s_resgid;
1054 * Allow the "check" option to be passed as a remount option.
1056 if (!parse_options (data, sbi)) {
1061 if ((sbi->s_mount_opt & EXT2_MOUNT_TAGGED) &&
1062 !(sb->s_flags & MS_TAGGED)) {
1063 printk("EXT2-fs: %s: tagging not permitted on remount.\n",
1068 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1069 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1072 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
1073 (old_mount_opt & EXT2_MOUNT_XIP)) &&
1074 invalidate_inodes(sb))
1075 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
1076 "xip remain in cache (no functional problem)");
1077 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1079 if (*flags & MS_RDONLY) {
1080 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1081 !(sbi->s_mount_state & EXT2_VALID_FS))
1084 * OK, we are remounting a valid rw partition rdonly, so set
1085 * the rdonly flag and then mark the partition as valid again.
1087 es->s_state = cpu_to_le16(sbi->s_mount_state);
1088 es->s_mtime = cpu_to_le32(get_seconds());
1090 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1091 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1093 printk("EXT2-fs: %s: couldn't remount RDWR because of "
1094 "unsupported optional features (%x).\n",
1095 sb->s_id, le32_to_cpu(ret));
1100 * Mounting a RDONLY partition read-write, so reread and
1101 * store the current valid flag. (It may have been changed
1102 * by e2fsck since we originally mounted the partition.)
1104 sbi->s_mount_state = le16_to_cpu(es->s_state);
1105 if (!ext2_setup_super (sb, es, 0))
1106 sb->s_flags &= ~MS_RDONLY;
1108 ext2_sync_super(sb, es);
1111 sbi->s_mount_opt = old_opts.s_mount_opt;
1112 sbi->s_resuid = old_opts.s_resuid;
1113 sbi->s_resgid = old_opts.s_resgid;
1114 sb->s_flags = old_sb_flags;
1118 static int ext2_statfs (struct dentry * dentry, struct kstatfs * buf)
1120 struct super_block *sb = dentry->d_sb;
1121 struct ext2_sb_info *sbi = EXT2_SB(sb);
1122 struct ext2_super_block *es = sbi->s_es;
1123 unsigned long overhead;
1127 if (test_opt (sb, MINIX_DF))
1131 * Compute the overhead (FS structures)
1135 * All of the blocks before first_data_block are
1138 overhead = le32_to_cpu(es->s_first_data_block);
1141 * Add the overhead attributed to the superblock and
1142 * block group descriptors. If the sparse superblocks
1143 * feature is turned on, then not all groups have this.
1145 for (i = 0; i < sbi->s_groups_count; i++)
1146 overhead += ext2_bg_has_super(sb, i) +
1147 ext2_bg_num_gdb(sb, i);
1150 * Every block group has an inode bitmap, a block
1151 * bitmap, and an inode table.
1153 overhead += (sbi->s_groups_count *
1154 (2 + sbi->s_itb_per_group));
1157 buf->f_type = EXT2_SUPER_MAGIC;
1158 buf->f_bsize = sb->s_blocksize;
1159 buf->f_blocks = le32_to_cpu(es->s_blocks_count) - overhead;
1160 buf->f_bfree = ext2_count_free_blocks(sb);
1161 buf->f_bavail = buf->f_bfree - le32_to_cpu(es->s_r_blocks_count);
1162 if (buf->f_bfree < le32_to_cpu(es->s_r_blocks_count))
1164 buf->f_files = le32_to_cpu(es->s_inodes_count);
1165 buf->f_ffree = ext2_count_free_inodes(sb);
1166 buf->f_namelen = EXT2_NAME_LEN;
1167 fsid = le64_to_cpup((void *)es->s_uuid) ^
1168 le64_to_cpup((void *)es->s_uuid + sizeof(u64));
1169 buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
1170 buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
1174 static int ext2_get_sb(struct file_system_type *fs_type,
1175 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
1177 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super, mnt);
1182 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1183 * acquiring the locks... As quota files are never truncated and quota code
1184 * itself serializes the operations (and noone else should touch the files)
1185 * we don't have to be afraid of races */
1186 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1187 size_t len, loff_t off)
1189 struct inode *inode = sb_dqopt(sb)->files[type];
1190 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1192 int offset = off & (sb->s_blocksize - 1);
1195 struct buffer_head tmp_bh;
1196 struct buffer_head *bh;
1197 loff_t i_size = i_size_read(inode);
1201 if (off+len > i_size)
1204 while (toread > 0) {
1205 tocopy = sb->s_blocksize - offset < toread ?
1206 sb->s_blocksize - offset : toread;
1209 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1212 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1213 memset(data, 0, tocopy);
1215 bh = sb_bread(sb, tmp_bh.b_blocknr);
1218 memcpy(data, bh->b_data+offset, tocopy);
1229 /* Write to quotafile */
1230 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1231 const char *data, size_t len, loff_t off)
1233 struct inode *inode = sb_dqopt(sb)->files[type];
1234 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1236 int offset = off & (sb->s_blocksize - 1);
1238 size_t towrite = len;
1239 struct buffer_head tmp_bh;
1240 struct buffer_head *bh;
1242 mutex_lock_nested(&inode->i_mutex, I_MUTEX_QUOTA);
1243 while (towrite > 0) {
1244 tocopy = sb->s_blocksize - offset < towrite ?
1245 sb->s_blocksize - offset : towrite;
1248 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1251 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1252 bh = sb_bread(sb, tmp_bh.b_blocknr);
1254 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1260 memcpy(bh->b_data+offset, data, tocopy);
1261 flush_dcache_page(bh->b_page);
1262 set_buffer_uptodate(bh);
1263 mark_buffer_dirty(bh);
1274 if (inode->i_size < off+len-towrite)
1275 i_size_write(inode, off+len-towrite);
1277 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1278 mark_inode_dirty(inode);
1279 mutex_unlock(&inode->i_mutex);
1280 return len - towrite;
1285 static struct file_system_type ext2_fs_type = {
1286 .owner = THIS_MODULE,
1288 .get_sb = ext2_get_sb,
1289 .kill_sb = kill_block_super,
1290 .fs_flags = FS_REQUIRES_DEV,
1293 static int __init init_ext2_fs(void)
1295 int err = init_ext2_xattr();
1298 err = init_inodecache();
1301 err = register_filesystem(&ext2_fs_type);
1306 destroy_inodecache();
1312 static void __exit exit_ext2_fs(void)
1314 unregister_filesystem(&ext2_fs_type);
1315 destroy_inodecache();
1319 module_init(init_ext2_fs)
1320 module_exit(exit_ext2_fs)