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 /* Yes, most of these are left as NULL!!
256 * A NULL value implies the default, which works with ext2-like file
257 * systems, but can be improved upon.
258 * Currently only get_parent is required.
260 static struct export_operations ext2_export_ops = {
261 .get_parent = ext2_get_parent,
264 static unsigned long get_sb_block(void **data)
266 unsigned long sb_block;
267 char *options = (char *) *data;
269 if (!options || strncmp(options, "sb=", 3) != 0)
270 return 1; /* Default location */
272 sb_block = simple_strtoul(options, &options, 0);
273 if (*options && *options != ',') {
274 printk("EXT2-fs: Invalid sb specification: %s\n",
280 *data = (void *) options;
285 Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
286 Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic,
287 Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug,
288 Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr,
289 Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota,
290 Opt_usrquota, Opt_grpquota, Opt_tagxid
293 static match_table_t tokens = {
294 {Opt_bsd_df, "bsddf"},
295 {Opt_minix_df, "minixdf"},
296 {Opt_grpid, "grpid"},
297 {Opt_grpid, "bsdgroups"},
298 {Opt_nogrpid, "nogrpid"},
299 {Opt_nogrpid, "sysvgroups"},
300 {Opt_resgid, "resgid=%u"},
301 {Opt_resuid, "resuid=%u"},
303 {Opt_err_cont, "errors=continue"},
304 {Opt_err_panic, "errors=panic"},
305 {Opt_err_ro, "errors=remount-ro"},
306 {Opt_nouid32, "nouid32"},
307 {Opt_nocheck, "check=none"},
308 {Opt_nocheck, "nocheck"},
309 {Opt_debug, "debug"},
310 {Opt_oldalloc, "oldalloc"},
311 {Opt_orlov, "orlov"},
313 {Opt_user_xattr, "user_xattr"},
314 {Opt_nouser_xattr, "nouser_xattr"},
316 {Opt_noacl, "noacl"},
318 {Opt_tagxid, "tagxid"},
319 {Opt_grpquota, "grpquota"},
320 {Opt_ignore, "noquota"},
321 {Opt_quota, "quota"},
322 {Opt_usrquota, "usrquota"},
326 static int parse_options (char * options,
327 struct ext2_sb_info *sbi)
330 substring_t args[MAX_OPT_ARGS];
331 unsigned long kind = EXT2_MOUNT_ERRORS_CONT;
337 while ((p = strsep (&options, ",")) != NULL) {
342 token = match_token(p, tokens, args);
345 clear_opt (sbi->s_mount_opt, MINIX_DF);
348 set_opt (sbi->s_mount_opt, MINIX_DF);
351 set_opt (sbi->s_mount_opt, GRPID);
354 clear_opt (sbi->s_mount_opt, GRPID);
357 if (match_int(&args[0], &option))
359 sbi->s_resuid = option;
362 if (match_int(&args[0], &option))
364 sbi->s_resgid = option;
367 /* handled by get_sb_block() instead of here */
368 /* *sb_block = match_int(&args[0]); */
371 kind = EXT2_MOUNT_ERRORS_PANIC;
374 kind = EXT2_MOUNT_ERRORS_RO;
377 kind = EXT2_MOUNT_ERRORS_CONT;
380 set_opt (sbi->s_mount_opt, NO_UID32);
382 #ifndef CONFIG_INOXID_NONE
384 set_opt (sbi->s_mount_opt, TAGXID);
388 clear_opt (sbi->s_mount_opt, CHECK);
391 set_opt (sbi->s_mount_opt, DEBUG);
394 set_opt (sbi->s_mount_opt, OLDALLOC);
397 clear_opt (sbi->s_mount_opt, OLDALLOC);
400 set_opt (sbi->s_mount_opt, NOBH);
402 #ifdef CONFIG_EXT2_FS_XATTR
404 set_opt (sbi->s_mount_opt, XATTR_USER);
406 case Opt_nouser_xattr:
407 clear_opt (sbi->s_mount_opt, XATTR_USER);
411 case Opt_nouser_xattr:
412 printk("EXT2 (no)user_xattr options not supported\n");
415 #ifdef CONFIG_EXT2_FS_POSIX_ACL
417 set_opt(sbi->s_mount_opt, POSIX_ACL);
420 clear_opt(sbi->s_mount_opt, POSIX_ACL);
425 printk("EXT2 (no)acl options not supported\n");
429 #ifdef CONFIG_EXT2_FS_XIP
430 set_opt (sbi->s_mount_opt, XIP);
432 printk("EXT2 xip option not supported\n");
436 #if defined(CONFIG_QUOTA)
439 set_opt(sbi->s_mount_opt, USRQUOTA);
443 set_opt(sbi->s_mount_opt, GRPQUOTA);
450 "EXT2-fs: quota operations not supported.\n");
461 sbi->s_mount_opt |= kind;
465 static int ext2_setup_super (struct super_block * sb,
466 struct ext2_super_block * es,
470 struct ext2_sb_info *sbi = EXT2_SB(sb);
472 if (le32_to_cpu(es->s_rev_level) > EXT2_MAX_SUPP_REV) {
473 printk ("EXT2-fs warning: revision level too high, "
474 "forcing read-only mode\n");
479 if (!(sbi->s_mount_state & EXT2_VALID_FS))
480 printk ("EXT2-fs warning: mounting unchecked fs, "
481 "running e2fsck is recommended\n");
482 else if ((sbi->s_mount_state & EXT2_ERROR_FS))
483 printk ("EXT2-fs warning: mounting fs with errors, "
484 "running e2fsck is recommended\n");
485 else if ((__s16) le16_to_cpu(es->s_max_mnt_count) >= 0 &&
486 le16_to_cpu(es->s_mnt_count) >=
487 (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
488 printk ("EXT2-fs warning: maximal mount count reached, "
489 "running e2fsck is recommended\n");
490 else if (le32_to_cpu(es->s_checkinterval) &&
491 (le32_to_cpu(es->s_lastcheck) + le32_to_cpu(es->s_checkinterval) <= get_seconds()))
492 printk ("EXT2-fs warning: checktime reached, "
493 "running e2fsck is recommended\n");
494 if (!le16_to_cpu(es->s_max_mnt_count))
495 es->s_max_mnt_count = cpu_to_le16(EXT2_DFL_MAX_MNT_COUNT);
496 es->s_mnt_count=cpu_to_le16(le16_to_cpu(es->s_mnt_count) + 1);
497 ext2_write_super(sb);
498 if (test_opt (sb, DEBUG))
499 printk ("[EXT II FS %s, %s, bs=%lu, fs=%lu, gc=%lu, "
500 "bpg=%lu, ipg=%lu, mo=%04lx]\n",
501 EXT2FS_VERSION, EXT2FS_DATE, sb->s_blocksize,
504 EXT2_BLOCKS_PER_GROUP(sb),
505 EXT2_INODES_PER_GROUP(sb),
510 static int ext2_check_descriptors (struct super_block * sb)
514 struct ext2_sb_info *sbi = EXT2_SB(sb);
515 unsigned long block = le32_to_cpu(sbi->s_es->s_first_data_block);
516 struct ext2_group_desc * gdp = NULL;
518 ext2_debug ("Checking group descriptors");
520 for (i = 0; i < sbi->s_groups_count; i++)
522 if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
523 gdp = (struct ext2_group_desc *) sbi->s_group_desc[desc_block++]->b_data;
524 if (le32_to_cpu(gdp->bg_block_bitmap) < block ||
525 le32_to_cpu(gdp->bg_block_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
527 ext2_error (sb, "ext2_check_descriptors",
528 "Block bitmap for group %d"
529 " not in group (block %lu)!",
530 i, (unsigned long) le32_to_cpu(gdp->bg_block_bitmap));
533 if (le32_to_cpu(gdp->bg_inode_bitmap) < block ||
534 le32_to_cpu(gdp->bg_inode_bitmap) >= block + EXT2_BLOCKS_PER_GROUP(sb))
536 ext2_error (sb, "ext2_check_descriptors",
537 "Inode bitmap for group %d"
538 " not in group (block %lu)!",
539 i, (unsigned long) le32_to_cpu(gdp->bg_inode_bitmap));
542 if (le32_to_cpu(gdp->bg_inode_table) < block ||
543 le32_to_cpu(gdp->bg_inode_table) + sbi->s_itb_per_group >=
544 block + EXT2_BLOCKS_PER_GROUP(sb))
546 ext2_error (sb, "ext2_check_descriptors",
547 "Inode table for group %d"
548 " not in group (block %lu)!",
549 i, (unsigned long) le32_to_cpu(gdp->bg_inode_table));
552 block += EXT2_BLOCKS_PER_GROUP(sb);
558 #define log2(n) ffz(~(n))
561 * Maximal file size. There is a direct, and {,double-,triple-}indirect
562 * block limit, and also a limit of (2^32 - 1) 512-byte sectors in i_blocks.
563 * We need to be 1 filesystem block less than the 2^32 sector limit.
565 static loff_t ext2_max_size(int bits)
567 loff_t res = EXT2_NDIR_BLOCKS;
568 /* This constant is calculated to be the largest file size for a
569 * dense, 4k-blocksize file such that the total number of
570 * sectors in the file, including data and all indirect blocks,
571 * does not exceed 2^32. */
572 const loff_t upper_limit = 0x1ff7fffd000LL;
574 res += 1LL << (bits-2);
575 res += 1LL << (2*(bits-2));
576 res += 1LL << (3*(bits-2));
578 if (res > upper_limit)
583 static unsigned long descriptor_loc(struct super_block *sb,
584 unsigned long logic_sb_block,
587 struct ext2_sb_info *sbi = EXT2_SB(sb);
588 unsigned long bg, first_data_block, first_meta_bg;
591 first_data_block = le32_to_cpu(sbi->s_es->s_first_data_block);
592 first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
594 if (!EXT2_HAS_INCOMPAT_FEATURE(sb, EXT2_FEATURE_INCOMPAT_META_BG) ||
596 return (logic_sb_block + nr + 1);
597 bg = sbi->s_desc_per_block * nr;
598 if (ext2_bg_has_super(sb, bg))
600 return (first_data_block + has_super + (bg * sbi->s_blocks_per_group));
603 static int ext2_fill_super(struct super_block *sb, void *data, int silent)
605 struct buffer_head * bh;
606 struct ext2_sb_info * sbi;
607 struct ext2_super_block * es;
610 unsigned long sb_block = get_sb_block(&data);
611 unsigned long logic_sb_block;
612 unsigned long offset = 0;
613 unsigned long def_mount_opts;
614 int blocksize = BLOCK_SIZE;
619 sbi = kmalloc(sizeof(*sbi), GFP_KERNEL);
623 memset(sbi, 0, sizeof(*sbi));
626 * See what the current blocksize for the device is, and
627 * use that as the blocksize. Otherwise (or if the blocksize
628 * is smaller than the default) use the default.
629 * This is important for devices that have a hardware
630 * sectorsize that is larger than the default.
632 blocksize = sb_min_blocksize(sb, BLOCK_SIZE);
634 printk ("EXT2-fs: unable to set blocksize\n");
639 * If the superblock doesn't start on a hardware sector boundary,
640 * calculate the offset.
642 if (blocksize != BLOCK_SIZE) {
643 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
644 offset = (sb_block*BLOCK_SIZE) % blocksize;
646 logic_sb_block = sb_block;
649 if (!(bh = sb_bread(sb, logic_sb_block))) {
650 printk ("EXT2-fs: unable to read superblock\n");
654 * Note: s_es must be initialized as soon as possible because
655 * some ext2 macro-instructions depend on its value
657 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
659 sb->s_magic = le16_to_cpu(es->s_magic);
661 if (sb->s_magic != EXT2_SUPER_MAGIC)
664 /* Set defaults before we parse the mount options */
665 def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
666 if (def_mount_opts & EXT2_DEFM_DEBUG)
667 set_opt(sbi->s_mount_opt, DEBUG);
668 if (def_mount_opts & EXT2_DEFM_BSDGROUPS)
669 set_opt(sbi->s_mount_opt, GRPID);
670 if (def_mount_opts & EXT2_DEFM_UID16)
671 set_opt(sbi->s_mount_opt, NO_UID32);
672 if (def_mount_opts & EXT2_DEFM_XATTR_USER)
673 set_opt(sbi->s_mount_opt, XATTR_USER);
674 if (def_mount_opts & EXT2_DEFM_ACL)
675 set_opt(sbi->s_mount_opt, POSIX_ACL);
677 if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_PANIC)
678 set_opt(sbi->s_mount_opt, ERRORS_PANIC);
679 else if (le16_to_cpu(sbi->s_es->s_errors) == EXT2_ERRORS_RO)
680 set_opt(sbi->s_mount_opt, ERRORS_RO);
682 sbi->s_resuid = le16_to_cpu(es->s_def_resuid);
683 sbi->s_resgid = le16_to_cpu(es->s_def_resgid);
685 if (!parse_options ((char *) data, sbi))
688 if (EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_TAGXID)
689 sb->s_flags |= MS_TAGXID;
690 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
691 ((EXT2_SB(sb)->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ?
694 ext2_xip_verify_sb(sb); /* see if bdev supports xip, unset
695 EXT2_MOUNT_XIP if not */
697 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV &&
698 (EXT2_HAS_COMPAT_FEATURE(sb, ~0U) ||
699 EXT2_HAS_RO_COMPAT_FEATURE(sb, ~0U) ||
700 EXT2_HAS_INCOMPAT_FEATURE(sb, ~0U)))
701 printk("EXT2-fs warning: feature flags set on rev 0 fs, "
702 "running e2fsck is recommended\n");
704 * Check feature flags regardless of the revision level, since we
705 * previously didn't change the revision level when setting the flags,
706 * so there is a chance incompat flags are set on a rev 0 filesystem.
708 features = EXT2_HAS_INCOMPAT_FEATURE(sb, ~EXT2_FEATURE_INCOMPAT_SUPP);
710 printk("EXT2-fs: %s: couldn't mount because of "
711 "unsupported optional features (%x).\n",
712 sb->s_id, le32_to_cpu(features));
715 if (!(sb->s_flags & MS_RDONLY) &&
716 (features = EXT2_HAS_RO_COMPAT_FEATURE(sb, ~EXT2_FEATURE_RO_COMPAT_SUPP))){
717 printk("EXT2-fs: %s: couldn't mount RDWR because of "
718 "unsupported optional features (%x).\n",
719 sb->s_id, le32_to_cpu(features));
723 blocksize = BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
725 if ((ext2_use_xip(sb)) && ((blocksize != PAGE_SIZE) ||
726 (sb->s_blocksize != blocksize))) {
728 printk("XIP: Unsupported blocksize\n");
732 /* If the blocksize doesn't match, re-read the thing.. */
733 if (sb->s_blocksize != blocksize) {
736 if (!sb_set_blocksize(sb, blocksize)) {
737 printk(KERN_ERR "EXT2-fs: blocksize too small for device.\n");
741 logic_sb_block = (sb_block*BLOCK_SIZE) / blocksize;
742 offset = (sb_block*BLOCK_SIZE) % blocksize;
743 bh = sb_bread(sb, logic_sb_block);
745 printk("EXT2-fs: Couldn't read superblock on "
749 es = (struct ext2_super_block *) (((char *)bh->b_data) + offset);
751 if (es->s_magic != cpu_to_le16(EXT2_SUPER_MAGIC)) {
752 printk ("EXT2-fs: Magic mismatch, very weird !\n");
757 sb->s_maxbytes = ext2_max_size(sb->s_blocksize_bits);
759 if (le32_to_cpu(es->s_rev_level) == EXT2_GOOD_OLD_REV) {
760 sbi->s_inode_size = EXT2_GOOD_OLD_INODE_SIZE;
761 sbi->s_first_ino = EXT2_GOOD_OLD_FIRST_INO;
763 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
764 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
765 if ((sbi->s_inode_size < EXT2_GOOD_OLD_INODE_SIZE) ||
766 (sbi->s_inode_size & (sbi->s_inode_size - 1)) ||
767 (sbi->s_inode_size > blocksize)) {
768 printk ("EXT2-fs: unsupported inode size: %d\n",
774 sbi->s_frag_size = EXT2_MIN_FRAG_SIZE <<
775 le32_to_cpu(es->s_log_frag_size);
776 if (sbi->s_frag_size == 0)
778 sbi->s_frags_per_block = sb->s_blocksize / sbi->s_frag_size;
780 sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
781 sbi->s_frags_per_group = le32_to_cpu(es->s_frags_per_group);
782 sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
784 if (EXT2_INODE_SIZE(sb) == 0)
786 sbi->s_inodes_per_block = sb->s_blocksize / EXT2_INODE_SIZE(sb);
787 if (sbi->s_inodes_per_block == 0)
789 sbi->s_itb_per_group = sbi->s_inodes_per_group /
790 sbi->s_inodes_per_block;
791 sbi->s_desc_per_block = sb->s_blocksize /
792 sizeof (struct ext2_group_desc);
794 sbi->s_mount_state = le16_to_cpu(es->s_state);
795 sbi->s_addr_per_block_bits =
796 log2 (EXT2_ADDR_PER_BLOCK(sb));
797 sbi->s_desc_per_block_bits =
798 log2 (EXT2_DESC_PER_BLOCK(sb));
800 if (sb->s_magic != EXT2_SUPER_MAGIC)
803 if (sb->s_blocksize != bh->b_size) {
805 printk ("VFS: Unsupported blocksize on dev "
810 if (sb->s_blocksize != sbi->s_frag_size) {
811 printk ("EXT2-fs: fragsize %lu != blocksize %lu (not supported yet)\n",
812 sbi->s_frag_size, sb->s_blocksize);
816 if (sbi->s_blocks_per_group > sb->s_blocksize * 8) {
817 printk ("EXT2-fs: #blocks per group too big: %lu\n",
818 sbi->s_blocks_per_group);
821 if (sbi->s_frags_per_group > sb->s_blocksize * 8) {
822 printk ("EXT2-fs: #fragments per group too big: %lu\n",
823 sbi->s_frags_per_group);
826 if (sbi->s_inodes_per_group > sb->s_blocksize * 8) {
827 printk ("EXT2-fs: #inodes per group too big: %lu\n",
828 sbi->s_inodes_per_group);
832 if (EXT2_BLOCKS_PER_GROUP(sb) == 0)
834 sbi->s_groups_count = (le32_to_cpu(es->s_blocks_count) -
835 le32_to_cpu(es->s_first_data_block) +
836 EXT2_BLOCKS_PER_GROUP(sb) - 1) /
837 EXT2_BLOCKS_PER_GROUP(sb);
838 db_count = (sbi->s_groups_count + EXT2_DESC_PER_BLOCK(sb) - 1) /
839 EXT2_DESC_PER_BLOCK(sb);
840 sbi->s_group_desc = kmalloc (db_count * sizeof (struct buffer_head *), GFP_KERNEL);
841 if (sbi->s_group_desc == NULL) {
842 printk ("EXT2-fs: not enough memory\n");
845 percpu_counter_init(&sbi->s_freeblocks_counter);
846 percpu_counter_init(&sbi->s_freeinodes_counter);
847 percpu_counter_init(&sbi->s_dirs_counter);
848 bgl_lock_init(&sbi->s_blockgroup_lock);
849 sbi->s_debts = kmalloc(sbi->s_groups_count * sizeof(*sbi->s_debts),
852 printk ("EXT2-fs: not enough memory\n");
853 goto failed_mount_group_desc;
855 memset(sbi->s_debts, 0, sbi->s_groups_count * sizeof(*sbi->s_debts));
856 for (i = 0; i < db_count; i++) {
857 block = descriptor_loc(sb, logic_sb_block, i);
858 sbi->s_group_desc[i] = sb_bread(sb, block);
859 if (!sbi->s_group_desc[i]) {
860 for (j = 0; j < i; j++)
861 brelse (sbi->s_group_desc[j]);
862 printk ("EXT2-fs: unable to read group descriptors\n");
863 goto failed_mount_group_desc;
866 if (!ext2_check_descriptors (sb)) {
867 printk ("EXT2-fs: group descriptors corrupted!\n");
871 sbi->s_gdb_count = db_count;
872 get_random_bytes(&sbi->s_next_generation, sizeof(u32));
873 spin_lock_init(&sbi->s_next_gen_lock);
875 * set up enough so that it can read an inode
877 sb->s_op = &ext2_sops;
878 sb->s_export_op = &ext2_export_ops;
879 sb->s_xattr = ext2_xattr_handlers;
880 root = iget(sb, EXT2_ROOT_INO);
881 sb->s_root = d_alloc_root(root);
884 printk(KERN_ERR "EXT2-fs: get root inode failed\n");
887 if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
890 printk(KERN_ERR "EXT2-fs: corrupt root inode, run e2fsck\n");
893 if (EXT2_HAS_COMPAT_FEATURE(sb, EXT3_FEATURE_COMPAT_HAS_JOURNAL))
894 ext2_warning(sb, __FUNCTION__,
895 "mounting ext3 filesystem as ext2");
896 ext2_setup_super (sb, es, sb->s_flags & MS_RDONLY);
897 percpu_counter_mod(&sbi->s_freeblocks_counter,
898 ext2_count_free_blocks(sb));
899 percpu_counter_mod(&sbi->s_freeinodes_counter,
900 ext2_count_free_inodes(sb));
901 percpu_counter_mod(&sbi->s_dirs_counter,
902 ext2_count_dirs(sb));
907 printk("VFS: Can't find an ext2 filesystem on dev %s.\n",
912 for (i = 0; i < db_count; i++)
913 brelse(sbi->s_group_desc[i]);
914 failed_mount_group_desc:
915 kfree(sbi->s_group_desc);
920 sb->s_fs_info = NULL;
925 static void ext2_commit_super (struct super_block * sb,
926 struct ext2_super_block * es)
928 es->s_wtime = cpu_to_le32(get_seconds());
929 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
933 static void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es)
935 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
936 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
937 es->s_wtime = cpu_to_le32(get_seconds());
938 mark_buffer_dirty(EXT2_SB(sb)->s_sbh);
939 sync_dirty_buffer(EXT2_SB(sb)->s_sbh);
944 * In the second extended file system, it is not necessary to
945 * write the super block since we use a mapping of the
946 * disk super block in a buffer.
948 * However, this function is still used to set the fs valid
949 * flags to 0. We need to set this flag to 0 since the fs
950 * may have been checked while mounted and e2fsck may have
951 * set s_state to EXT2_VALID_FS after some corrections.
954 void ext2_write_super (struct super_block * sb)
956 struct ext2_super_block * es;
958 if (!(sb->s_flags & MS_RDONLY)) {
959 es = EXT2_SB(sb)->s_es;
961 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS) {
962 ext2_debug ("setting valid to 0\n");
963 es->s_state = cpu_to_le16(le16_to_cpu(es->s_state) &
965 es->s_free_blocks_count = cpu_to_le32(ext2_count_free_blocks(sb));
966 es->s_free_inodes_count = cpu_to_le32(ext2_count_free_inodes(sb));
967 es->s_mtime = cpu_to_le32(get_seconds());
968 ext2_sync_super(sb, es);
970 ext2_commit_super (sb, es);
976 static int ext2_remount (struct super_block * sb, int * flags, char * data)
978 struct ext2_sb_info * sbi = EXT2_SB(sb);
979 struct ext2_super_block * es;
980 unsigned long old_mount_opt = sbi->s_mount_opt;
981 struct ext2_mount_options old_opts;
982 unsigned long old_sb_flags;
985 /* Store the old options */
986 old_sb_flags = sb->s_flags;
987 old_opts.s_mount_opt = sbi->s_mount_opt;
988 old_opts.s_resuid = sbi->s_resuid;
989 old_opts.s_resgid = sbi->s_resgid;
992 * Allow the "check" option to be passed as a remount option.
994 if (!parse_options (data, sbi)) {
999 if ((sbi->s_mount_opt & EXT2_MOUNT_TAGXID) &&
1000 !(sb->s_flags & MS_TAGXID)) {
1001 printk("EXT2-fs: %s: tagxid not permitted on remount.\n",
1006 sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
1007 ((sbi->s_mount_opt & EXT2_MOUNT_POSIX_ACL) ? MS_POSIXACL : 0);
1010 if (((sbi->s_mount_opt & EXT2_MOUNT_XIP) !=
1011 (old_mount_opt & EXT2_MOUNT_XIP)) &&
1012 invalidate_inodes(sb))
1013 ext2_warning(sb, __FUNCTION__, "busy inodes while remounting "\
1014 "xip remain in cache (no functional problem)");
1015 if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
1017 if (*flags & MS_RDONLY) {
1018 if (le16_to_cpu(es->s_state) & EXT2_VALID_FS ||
1019 !(sbi->s_mount_state & EXT2_VALID_FS))
1022 * OK, we are remounting a valid rw partition rdonly, so set
1023 * the rdonly flag and then mark the partition as valid again.
1025 es->s_state = cpu_to_le16(sbi->s_mount_state);
1026 es->s_mtime = cpu_to_le32(get_seconds());
1028 __le32 ret = EXT2_HAS_RO_COMPAT_FEATURE(sb,
1029 ~EXT2_FEATURE_RO_COMPAT_SUPP);
1031 printk("EXT2-fs: %s: couldn't remount RDWR because of "
1032 "unsupported optional features (%x).\n",
1033 sb->s_id, le32_to_cpu(ret));
1038 * Mounting a RDONLY partition read-write, so reread and
1039 * store the current valid flag. (It may have been changed
1040 * by e2fsck since we originally mounted the partition.)
1042 sbi->s_mount_state = le16_to_cpu(es->s_state);
1043 if (!ext2_setup_super (sb, es, 0))
1044 sb->s_flags &= ~MS_RDONLY;
1046 ext2_sync_super(sb, es);
1049 sbi->s_mount_opt = old_opts.s_mount_opt;
1050 sbi->s_resuid = old_opts.s_resuid;
1051 sbi->s_resgid = old_opts.s_resgid;
1052 sb->s_flags = old_sb_flags;
1056 static int ext2_statfs (struct super_block * sb, struct kstatfs * buf)
1058 struct ext2_sb_info *sbi = EXT2_SB(sb);
1059 unsigned long overhead;
1062 if (test_opt (sb, MINIX_DF))
1066 * Compute the overhead (FS structures)
1070 * All of the blocks before first_data_block are
1073 overhead = le32_to_cpu(sbi->s_es->s_first_data_block);
1076 * Add the overhead attributed to the superblock and
1077 * block group descriptors. If the sparse superblocks
1078 * feature is turned on, then not all groups have this.
1080 for (i = 0; i < sbi->s_groups_count; i++)
1081 overhead += ext2_bg_has_super(sb, i) +
1082 ext2_bg_num_gdb(sb, i);
1085 * Every block group has an inode bitmap, a block
1086 * bitmap, and an inode table.
1088 overhead += (sbi->s_groups_count *
1089 (2 + sbi->s_itb_per_group));
1092 buf->f_type = EXT2_SUPER_MAGIC;
1093 buf->f_bsize = sb->s_blocksize;
1094 buf->f_blocks = le32_to_cpu(sbi->s_es->s_blocks_count) - overhead;
1095 buf->f_bfree = ext2_count_free_blocks(sb);
1096 buf->f_bavail = buf->f_bfree - le32_to_cpu(sbi->s_es->s_r_blocks_count);
1097 if (buf->f_bfree < le32_to_cpu(sbi->s_es->s_r_blocks_count))
1099 buf->f_files = le32_to_cpu(sbi->s_es->s_inodes_count);
1100 buf->f_ffree = ext2_count_free_inodes (sb);
1101 buf->f_namelen = EXT2_NAME_LEN;
1105 static struct super_block *ext2_get_sb(struct file_system_type *fs_type,
1106 int flags, const char *dev_name, void *data)
1108 return get_sb_bdev(fs_type, flags, dev_name, data, ext2_fill_super);
1113 /* Read data from quotafile - avoid pagecache and such because we cannot afford
1114 * acquiring the locks... As quota files are never truncated and quota code
1115 * itself serializes the operations (and noone else should touch the files)
1116 * we don't have to be afraid of races */
1117 static ssize_t ext2_quota_read(struct super_block *sb, int type, char *data,
1118 size_t len, loff_t off)
1120 struct inode *inode = sb_dqopt(sb)->files[type];
1121 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1123 int offset = off & (sb->s_blocksize - 1);
1126 struct buffer_head tmp_bh;
1127 struct buffer_head *bh;
1128 loff_t i_size = i_size_read(inode);
1132 if (off+len > i_size)
1135 while (toread > 0) {
1136 tocopy = sb->s_blocksize - offset < toread ?
1137 sb->s_blocksize - offset : toread;
1140 err = ext2_get_block(inode, blk, &tmp_bh, 0);
1143 if (!buffer_mapped(&tmp_bh)) /* A hole? */
1144 memset(data, 0, tocopy);
1146 bh = sb_bread(sb, tmp_bh.b_blocknr);
1149 memcpy(data, bh->b_data+offset, tocopy);
1160 /* Write to quotafile */
1161 static ssize_t ext2_quota_write(struct super_block *sb, int type,
1162 const char *data, size_t len, loff_t off)
1164 struct inode *inode = sb_dqopt(sb)->files[type];
1165 sector_t blk = off >> EXT2_BLOCK_SIZE_BITS(sb);
1167 int offset = off & (sb->s_blocksize - 1);
1169 size_t towrite = len;
1170 struct buffer_head tmp_bh;
1171 struct buffer_head *bh;
1173 mutex_lock(&inode->i_mutex);
1174 while (towrite > 0) {
1175 tocopy = sb->s_blocksize - offset < towrite ?
1176 sb->s_blocksize - offset : towrite;
1179 err = ext2_get_block(inode, blk, &tmp_bh, 1);
1182 if (offset || tocopy != EXT2_BLOCK_SIZE(sb))
1183 bh = sb_bread(sb, tmp_bh.b_blocknr);
1185 bh = sb_getblk(sb, tmp_bh.b_blocknr);
1191 memcpy(bh->b_data+offset, data, tocopy);
1192 flush_dcache_page(bh->b_page);
1193 set_buffer_uptodate(bh);
1194 mark_buffer_dirty(bh);
1205 if (inode->i_size < off+len-towrite)
1206 i_size_write(inode, off+len-towrite);
1208 inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1209 mark_inode_dirty(inode);
1210 mutex_unlock(&inode->i_mutex);
1211 return len - towrite;
1216 static struct file_system_type ext2_fs_type = {
1217 .owner = THIS_MODULE,
1219 .get_sb = ext2_get_sb,
1220 .kill_sb = kill_block_super,
1221 .fs_flags = FS_REQUIRES_DEV,
1224 static int __init init_ext2_fs(void)
1226 int err = init_ext2_xattr();
1229 err = init_inodecache();
1232 err = register_filesystem(&ext2_fs_type);
1237 destroy_inodecache();
1243 static void __exit exit_ext2_fs(void)
1245 unregister_filesystem(&ext2_fs_type);
1246 destroy_inodecache();
1250 module_init(init_ext2_fs)
1251 module_exit(exit_ext2_fs)