4 * Written 1992,1993 by Werner Almesberger
5 * VFAT extensions by Gordon Chaffee, merged with msdos fs by Henrik Storner
6 * Rewritten for the constant inumbers support by Al Viro
10 * Max Cohan: Fixed invalid FSINFO offset when info_sector is 0
13 #include <linux/module.h>
14 #include <linux/init.h>
15 #include <linux/time.h>
16 #include <linux/slab.h>
17 #include <linux/seq_file.h>
18 #include <linux/pagemap.h>
19 #include <linux/mpage.h>
20 #include <linux/buffer_head.h>
21 #include <linux/mount.h>
22 #include <linux/aio.h>
23 #include <linux/vfs.h>
24 #include <linux/parser.h>
25 #include <linux/uio.h>
26 #include <linux/writeback.h>
27 #include <linux/log2.h>
28 #include <linux/hash.h>
29 #include <linux/blkdev.h>
30 #include <asm/unaligned.h>
33 #ifndef CONFIG_FAT_DEFAULT_IOCHARSET
34 /* if user don't select VFAT, this is undefined. */
35 #define CONFIG_FAT_DEFAULT_IOCHARSET ""
38 static int fat_default_codepage = CONFIG_FAT_DEFAULT_CODEPAGE;
39 static char fat_default_iocharset[] = CONFIG_FAT_DEFAULT_IOCHARSET;
42 static int fat_add_cluster(struct inode *inode)
46 err = fat_alloc_clusters(inode, &cluster, 1);
49 /* FIXME: this cluster should be added after data of this
50 * cluster is writed */
51 err = fat_chain_add(inode, cluster, 1);
53 fat_free_clusters(inode, cluster);
57 static inline int __fat_get_block(struct inode *inode, sector_t iblock,
58 unsigned long *max_blocks,
59 struct buffer_head *bh_result, int create)
61 struct super_block *sb = inode->i_sb;
62 struct msdos_sb_info *sbi = MSDOS_SB(sb);
63 unsigned long mapped_blocks;
67 err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
71 map_bh(bh_result, sb, phys);
72 *max_blocks = min(mapped_blocks, *max_blocks);
78 if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) {
79 fat_fs_error(sb, "corrupted file size (i_pos %lld, %lld)",
80 MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private);
84 offset = (unsigned long)iblock & (sbi->sec_per_clus - 1);
86 /* TODO: multiple cluster allocation would be desirable. */
87 err = fat_add_cluster(inode);
91 /* available blocks on this cluster */
92 mapped_blocks = sbi->sec_per_clus - offset;
94 *max_blocks = min(mapped_blocks, *max_blocks);
95 MSDOS_I(inode)->mmu_private += *max_blocks << sb->s_blocksize_bits;
97 err = fat_bmap(inode, iblock, &phys, &mapped_blocks, create);
102 BUG_ON(*max_blocks != mapped_blocks);
103 set_buffer_new(bh_result);
104 map_bh(bh_result, sb, phys);
109 static int fat_get_block(struct inode *inode, sector_t iblock,
110 struct buffer_head *bh_result, int create)
112 struct super_block *sb = inode->i_sb;
113 unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
116 err = __fat_get_block(inode, iblock, &max_blocks, bh_result, create);
119 bh_result->b_size = max_blocks << sb->s_blocksize_bits;
123 static int fat_writepage(struct page *page, struct writeback_control *wbc)
125 return block_write_full_page(page, fat_get_block, wbc);
128 static int fat_writepages(struct address_space *mapping,
129 struct writeback_control *wbc)
131 return mpage_writepages(mapping, wbc, fat_get_block);
134 static int fat_readpage(struct file *file, struct page *page)
136 return mpage_readpage(page, fat_get_block);
139 static int fat_readpages(struct file *file, struct address_space *mapping,
140 struct list_head *pages, unsigned nr_pages)
142 return mpage_readpages(mapping, pages, nr_pages, fat_get_block);
145 static void fat_write_failed(struct address_space *mapping, loff_t to)
147 struct inode *inode = mapping->host;
149 if (to > inode->i_size) {
150 truncate_pagecache(inode, inode->i_size);
151 fat_truncate_blocks(inode, inode->i_size);
155 static int fat_write_begin(struct file *file, struct address_space *mapping,
156 loff_t pos, unsigned len, unsigned flags,
157 struct page **pagep, void **fsdata)
162 err = cont_write_begin(file, mapping, pos, len, flags,
163 pagep, fsdata, fat_get_block,
164 &MSDOS_I(mapping->host)->mmu_private);
166 fat_write_failed(mapping, pos + len);
170 static int fat_write_end(struct file *file, struct address_space *mapping,
171 loff_t pos, unsigned len, unsigned copied,
172 struct page *pagep, void *fsdata)
174 struct inode *inode = mapping->host;
176 err = generic_write_end(file, mapping, pos, len, copied, pagep, fsdata);
178 fat_write_failed(mapping, pos + len);
179 if (!(err < 0) && !(MSDOS_I(inode)->i_attrs & ATTR_ARCH)) {
180 inode->i_mtime = inode->i_ctime = CURRENT_TIME_SEC;
181 MSDOS_I(inode)->i_attrs |= ATTR_ARCH;
182 mark_inode_dirty(inode);
187 static ssize_t fat_direct_IO(int rw, struct kiocb *iocb,
188 struct iov_iter *iter, loff_t offset)
190 struct file *file = iocb->ki_filp;
191 struct address_space *mapping = file->f_mapping;
192 struct inode *inode = mapping->host;
197 * FIXME: blockdev_direct_IO() doesn't use ->write_begin(),
198 * so we need to update the ->mmu_private to block boundary.
200 * But we must fill the remaining area or hole by nul for
201 * updating ->mmu_private.
203 * Return 0, and fallback to normal buffered write.
205 loff_t size = offset + iov_iter_count(iter);
206 if (MSDOS_I(inode)->mmu_private < size)
211 * FAT need to use the DIO_LOCKING for avoiding the race
212 * condition of fat_get_block() and ->truncate().
214 ret = blockdev_direct_IO(rw, iocb, inode, iter, offset, fat_get_block);
215 if (ret < 0 && (rw & WRITE))
216 fat_write_failed(mapping, offset + iov_iter_count(iter));
221 static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
225 /* fat_get_cluster() assumes the requested blocknr isn't truncated. */
226 down_read(&MSDOS_I(mapping->host)->truncate_lock);
227 blocknr = generic_block_bmap(mapping, block, fat_get_block);
228 up_read(&MSDOS_I(mapping->host)->truncate_lock);
233 static const struct address_space_operations fat_aops = {
234 .readpage = fat_readpage,
235 .readpages = fat_readpages,
236 .writepage = fat_writepage,
237 .writepages = fat_writepages,
238 .write_begin = fat_write_begin,
239 .write_end = fat_write_end,
240 .direct_IO = fat_direct_IO,
245 * New FAT inode stuff. We do the following:
246 * a) i_ino is constant and has nothing with on-disk location.
247 * b) FAT manages its own cache of directory entries.
248 * c) *This* cache is indexed by on-disk location.
249 * d) inode has an associated directory entry, all right, but
250 * it may be unhashed.
251 * e) currently entries are stored within struct inode. That should
253 * f) we deal with races in the following way:
254 * 1. readdir() and lookup() do FAT-dir-cache lookup.
255 * 2. rename() unhashes the F-d-c entry and rehashes it in
257 * 3. unlink() and rmdir() unhash F-d-c entry.
258 * 4. fat_write_inode() checks whether the thing is unhashed.
259 * If it is we silently return. If it isn't we do bread(),
260 * check if the location is still valid and retry if it
261 * isn't. Otherwise we do changes.
262 * 5. Spinlock is used to protect hash/unhash/location check/lookup
263 * 6. fat_evict_inode() unhashes the F-d-c entry.
264 * 7. lookup() and readdir() do igrab() if they find a F-d-c entry
265 * and consider negative result as cache miss.
268 static void fat_hash_init(struct super_block *sb)
270 struct msdos_sb_info *sbi = MSDOS_SB(sb);
273 spin_lock_init(&sbi->inode_hash_lock);
274 for (i = 0; i < FAT_HASH_SIZE; i++)
275 INIT_HLIST_HEAD(&sbi->inode_hashtable[i]);
278 static inline unsigned long fat_hash(loff_t i_pos)
280 return hash_32(i_pos, FAT_HASH_BITS);
283 static void dir_hash_init(struct super_block *sb)
285 struct msdos_sb_info *sbi = MSDOS_SB(sb);
288 spin_lock_init(&sbi->dir_hash_lock);
289 for (i = 0; i < FAT_HASH_SIZE; i++)
290 INIT_HLIST_HEAD(&sbi->dir_hashtable[i]);
293 void fat_attach(struct inode *inode, loff_t i_pos)
295 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
297 if (inode->i_ino != MSDOS_ROOT_INO) {
298 struct hlist_head *head = sbi->inode_hashtable
301 spin_lock(&sbi->inode_hash_lock);
302 MSDOS_I(inode)->i_pos = i_pos;
303 hlist_add_head(&MSDOS_I(inode)->i_fat_hash, head);
304 spin_unlock(&sbi->inode_hash_lock);
307 /* If NFS support is enabled, cache the mapping of start cluster
308 * to directory inode. This is used during reconnection of
309 * dentries to the filesystem root.
311 if (S_ISDIR(inode->i_mode) && sbi->options.nfs) {
312 struct hlist_head *d_head = sbi->dir_hashtable;
313 d_head += fat_dir_hash(MSDOS_I(inode)->i_logstart);
315 spin_lock(&sbi->dir_hash_lock);
316 hlist_add_head(&MSDOS_I(inode)->i_dir_hash, d_head);
317 spin_unlock(&sbi->dir_hash_lock);
320 EXPORT_SYMBOL_GPL(fat_attach);
322 void fat_detach(struct inode *inode)
324 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
325 spin_lock(&sbi->inode_hash_lock);
326 MSDOS_I(inode)->i_pos = 0;
327 hlist_del_init(&MSDOS_I(inode)->i_fat_hash);
328 spin_unlock(&sbi->inode_hash_lock);
330 if (S_ISDIR(inode->i_mode) && sbi->options.nfs) {
331 spin_lock(&sbi->dir_hash_lock);
332 hlist_del_init(&MSDOS_I(inode)->i_dir_hash);
333 spin_unlock(&sbi->dir_hash_lock);
336 EXPORT_SYMBOL_GPL(fat_detach);
338 struct inode *fat_iget(struct super_block *sb, loff_t i_pos)
340 struct msdos_sb_info *sbi = MSDOS_SB(sb);
341 struct hlist_head *head = sbi->inode_hashtable + fat_hash(i_pos);
342 struct msdos_inode_info *i;
343 struct inode *inode = NULL;
345 spin_lock(&sbi->inode_hash_lock);
346 hlist_for_each_entry(i, head, i_fat_hash) {
347 BUG_ON(i->vfs_inode.i_sb != sb);
348 if (i->i_pos != i_pos)
350 inode = igrab(&i->vfs_inode);
354 spin_unlock(&sbi->inode_hash_lock);
358 static int is_exec(unsigned char *extension)
360 unsigned char *exe_extensions = "EXECOMBAT", *walk;
362 for (walk = exe_extensions; *walk; walk += 3)
363 if (!strncmp(extension, walk, 3))
368 static int fat_calc_dir_size(struct inode *inode)
370 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
371 int ret, fclus, dclus;
374 if (MSDOS_I(inode)->i_start == 0)
377 ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus);
380 inode->i_size = (fclus + 1) << sbi->cluster_bits;
385 /* doesn't deal with root inode */
386 int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
388 struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
391 MSDOS_I(inode)->i_pos = 0;
392 inode->i_uid = sbi->options.fs_uid;
393 inode->i_gid = sbi->options.fs_gid;
395 inode->i_generation = get_seconds();
397 if ((de->attr & ATTR_DIR) && !IS_FREE(de->name)) {
398 inode->i_generation &= ~1;
399 inode->i_mode = fat_make_mode(sbi, de->attr, S_IRWXUGO);
400 inode->i_op = sbi->dir_ops;
401 inode->i_fop = &fat_dir_operations;
403 MSDOS_I(inode)->i_start = fat_get_start(sbi, de);
404 MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
405 error = fat_calc_dir_size(inode);
408 MSDOS_I(inode)->mmu_private = inode->i_size;
410 set_nlink(inode, fat_subdirs(inode));
411 } else { /* not a directory */
412 inode->i_generation |= 1;
413 inode->i_mode = fat_make_mode(sbi, de->attr,
414 ((sbi->options.showexec && !is_exec(de->name + 8))
415 ? S_IRUGO|S_IWUGO : S_IRWXUGO));
416 MSDOS_I(inode)->i_start = fat_get_start(sbi, de);
418 MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
419 inode->i_size = le32_to_cpu(de->size);
420 inode->i_op = &fat_file_inode_operations;
421 inode->i_fop = &fat_file_operations;
422 inode->i_mapping->a_ops = &fat_aops;
423 MSDOS_I(inode)->mmu_private = inode->i_size;
425 if (de->attr & ATTR_SYS) {
426 if (sbi->options.sys_immutable)
427 inode->i_flags |= S_IMMUTABLE;
429 fat_save_attrs(inode, de->attr);
431 inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
432 & ~((loff_t)sbi->cluster_size - 1)) >> 9;
434 fat_time_fat2unix(sbi, &inode->i_mtime, de->time, de->date, 0);
435 if (sbi->options.isvfat) {
436 fat_time_fat2unix(sbi, &inode->i_ctime, de->ctime,
437 de->cdate, de->ctime_cs);
438 fat_time_fat2unix(sbi, &inode->i_atime, 0, de->adate, 0);
440 inode->i_ctime = inode->i_atime = inode->i_mtime;
445 static inline void fat_lock_build_inode(struct msdos_sb_info *sbi)
447 if (sbi->options.nfs == FAT_NFS_NOSTALE_RO)
448 mutex_lock(&sbi->nfs_build_inode_lock);
451 static inline void fat_unlock_build_inode(struct msdos_sb_info *sbi)
453 if (sbi->options.nfs == FAT_NFS_NOSTALE_RO)
454 mutex_unlock(&sbi->nfs_build_inode_lock);
457 struct inode *fat_build_inode(struct super_block *sb,
458 struct msdos_dir_entry *de, loff_t i_pos)
463 fat_lock_build_inode(MSDOS_SB(sb));
464 inode = fat_iget(sb, i_pos);
467 inode = new_inode(sb);
469 inode = ERR_PTR(-ENOMEM);
472 inode->i_ino = iunique(sb, MSDOS_ROOT_INO);
473 inode->i_version = 1;
474 err = fat_fill_inode(inode, de);
477 inode = ERR_PTR(err);
480 fat_attach(inode, i_pos);
481 insert_inode_hash(inode);
483 fat_unlock_build_inode(MSDOS_SB(sb));
487 EXPORT_SYMBOL_GPL(fat_build_inode);
489 static void fat_evict_inode(struct inode *inode)
491 truncate_inode_pages(&inode->i_data, 0);
492 if (!inode->i_nlink) {
494 fat_truncate_blocks(inode, 0);
496 invalidate_inode_buffers(inode);
498 fat_cache_inval_inode(inode);
502 static void fat_set_state(struct super_block *sb,
503 unsigned int set, unsigned int force)
505 struct buffer_head *bh;
506 struct fat_boot_sector *b;
507 struct msdos_sb_info *sbi = sb->s_fs_info;
509 /* do not change any thing if mounted read only */
510 if ((sb->s_flags & MS_RDONLY) && !force)
513 /* do not change state if fs was dirty */
515 /* warn only on set (mount). */
517 fat_msg(sb, KERN_WARNING, "Volume was not properly "
518 "unmounted. Some data may be corrupt. "
523 bh = sb_bread(sb, 0);
525 fat_msg(sb, KERN_ERR, "unable to read boot sector "
526 "to mark fs as dirty");
530 b = (struct fat_boot_sector *) bh->b_data;
532 if (sbi->fat_bits == 32) {
534 b->fat32.state |= FAT_STATE_DIRTY;
536 b->fat32.state &= ~FAT_STATE_DIRTY;
537 } else /* fat 16 and 12 */ {
539 b->fat16.state |= FAT_STATE_DIRTY;
541 b->fat16.state &= ~FAT_STATE_DIRTY;
544 mark_buffer_dirty(bh);
545 sync_dirty_buffer(bh);
549 static void fat_put_super(struct super_block *sb)
551 struct msdos_sb_info *sbi = MSDOS_SB(sb);
553 fat_set_state(sb, 0, 0);
555 iput(sbi->fsinfo_inode);
556 iput(sbi->fat_inode);
558 unload_nls(sbi->nls_disk);
559 unload_nls(sbi->nls_io);
561 if (sbi->options.iocharset != fat_default_iocharset)
562 kfree(sbi->options.iocharset);
564 sb->s_fs_info = NULL;
568 static struct kmem_cache *fat_inode_cachep;
570 static struct inode *fat_alloc_inode(struct super_block *sb)
572 struct msdos_inode_info *ei;
573 ei = kmem_cache_alloc(fat_inode_cachep, GFP_NOFS);
577 init_rwsem(&ei->truncate_lock);
578 return &ei->vfs_inode;
581 static void fat_i_callback(struct rcu_head *head)
583 struct inode *inode = container_of(head, struct inode, i_rcu);
584 kmem_cache_free(fat_inode_cachep, MSDOS_I(inode));
587 static void fat_destroy_inode(struct inode *inode)
589 call_rcu(&inode->i_rcu, fat_i_callback);
592 static void init_once(void *foo)
594 struct msdos_inode_info *ei = (struct msdos_inode_info *)foo;
596 spin_lock_init(&ei->cache_lru_lock);
598 ei->cache_valid_id = FAT_CACHE_VALID + 1;
599 INIT_LIST_HEAD(&ei->cache_lru);
600 INIT_HLIST_NODE(&ei->i_fat_hash);
601 INIT_HLIST_NODE(&ei->i_dir_hash);
602 inode_init_once(&ei->vfs_inode);
605 static int __init fat_init_inodecache(void)
607 fat_inode_cachep = kmem_cache_create("fat_inode_cache",
608 sizeof(struct msdos_inode_info),
609 0, (SLAB_RECLAIM_ACCOUNT|
612 if (fat_inode_cachep == NULL)
617 static void __exit fat_destroy_inodecache(void)
620 * Make sure all delayed rcu free inodes are flushed before we
624 kmem_cache_destroy(fat_inode_cachep);
627 static int fat_remount(struct super_block *sb, int *flags, char *data)
630 struct msdos_sb_info *sbi = MSDOS_SB(sb);
631 *flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME);
633 /* make sure we update state on remount. */
634 new_rdonly = *flags & MS_RDONLY;
635 if (new_rdonly != (sb->s_flags & MS_RDONLY)) {
637 fat_set_state(sb, 0, 0);
639 fat_set_state(sb, 1, 1);
644 static int fat_statfs(struct dentry *dentry, struct kstatfs *buf)
646 struct super_block *sb = dentry->d_sb;
647 struct msdos_sb_info *sbi = MSDOS_SB(sb);
648 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
650 /* If the count of free cluster is still unknown, counts it here. */
651 if (sbi->free_clusters == -1 || !sbi->free_clus_valid) {
652 int err = fat_count_free_clusters(dentry->d_sb);
657 buf->f_type = dentry->d_sb->s_magic;
658 buf->f_bsize = sbi->cluster_size;
659 buf->f_blocks = sbi->max_cluster - FAT_START_ENT;
660 buf->f_bfree = sbi->free_clusters;
661 buf->f_bavail = sbi->free_clusters;
662 buf->f_fsid.val[0] = (u32)id;
663 buf->f_fsid.val[1] = (u32)(id >> 32);
665 (sbi->options.isvfat ? FAT_LFN_LEN : 12) * NLS_MAX_CHARSET_SIZE;
670 static int __fat_write_inode(struct inode *inode, int wait)
672 struct super_block *sb = inode->i_sb;
673 struct msdos_sb_info *sbi = MSDOS_SB(sb);
674 struct buffer_head *bh;
675 struct msdos_dir_entry *raw_entry;
680 if (inode->i_ino == MSDOS_ROOT_INO)
684 i_pos = fat_i_pos_read(sbi, inode);
688 fat_get_blknr_offset(sbi, i_pos, &blocknr, &offset);
689 bh = sb_bread(sb, blocknr);
691 fat_msg(sb, KERN_ERR, "unable to read inode block "
692 "for updating (i_pos %lld)", i_pos);
695 spin_lock(&sbi->inode_hash_lock);
696 if (i_pos != MSDOS_I(inode)->i_pos) {
697 spin_unlock(&sbi->inode_hash_lock);
702 raw_entry = &((struct msdos_dir_entry *) (bh->b_data))[offset];
703 if (S_ISDIR(inode->i_mode))
706 raw_entry->size = cpu_to_le32(inode->i_size);
707 raw_entry->attr = fat_make_attrs(inode);
708 fat_set_start(raw_entry, MSDOS_I(inode)->i_logstart);
709 fat_time_unix2fat(sbi, &inode->i_mtime, &raw_entry->time,
710 &raw_entry->date, NULL);
711 if (sbi->options.isvfat) {
713 fat_time_unix2fat(sbi, &inode->i_ctime, &raw_entry->ctime,
714 &raw_entry->cdate, &raw_entry->ctime_cs);
715 fat_time_unix2fat(sbi, &inode->i_atime, &atime,
716 &raw_entry->adate, NULL);
718 spin_unlock(&sbi->inode_hash_lock);
719 mark_buffer_dirty(bh);
722 err = sync_dirty_buffer(bh);
727 static int fat_write_inode(struct inode *inode, struct writeback_control *wbc)
731 if (inode->i_ino == MSDOS_FSINFO_INO) {
732 struct super_block *sb = inode->i_sb;
734 mutex_lock(&MSDOS_SB(sb)->s_lock);
735 err = fat_clusters_flush(sb);
736 mutex_unlock(&MSDOS_SB(sb)->s_lock);
738 err = __fat_write_inode(inode, wbc->sync_mode == WB_SYNC_ALL);
743 int fat_sync_inode(struct inode *inode)
745 return __fat_write_inode(inode, 1);
748 EXPORT_SYMBOL_GPL(fat_sync_inode);
750 static int fat_show_options(struct seq_file *m, struct dentry *root);
751 static const struct super_operations fat_sops = {
752 .alloc_inode = fat_alloc_inode,
753 .destroy_inode = fat_destroy_inode,
754 .write_inode = fat_write_inode,
755 .evict_inode = fat_evict_inode,
756 .put_super = fat_put_super,
757 .statfs = fat_statfs,
758 .remount_fs = fat_remount,
760 .show_options = fat_show_options,
763 static int fat_show_options(struct seq_file *m, struct dentry *root)
765 struct msdos_sb_info *sbi = MSDOS_SB(root->d_sb);
766 struct fat_mount_options *opts = &sbi->options;
767 int isvfat = opts->isvfat;
769 if (!uid_eq(opts->fs_uid, GLOBAL_ROOT_UID))
770 seq_printf(m, ",uid=%u",
771 from_kuid_munged(&init_user_ns, opts->fs_uid));
772 if (!gid_eq(opts->fs_gid, GLOBAL_ROOT_GID))
773 seq_printf(m, ",gid=%u",
774 from_kgid_munged(&init_user_ns, opts->fs_gid));
775 seq_printf(m, ",fmask=%04o", opts->fs_fmask);
776 seq_printf(m, ",dmask=%04o", opts->fs_dmask);
777 if (opts->allow_utime)
778 seq_printf(m, ",allow_utime=%04o", opts->allow_utime);
780 /* strip "cp" prefix from displayed option */
781 seq_printf(m, ",codepage=%s", &sbi->nls_disk->charset[2]);
784 seq_printf(m, ",iocharset=%s", sbi->nls_io->charset);
786 switch (opts->shortname) {
787 case VFAT_SFN_DISPLAY_WIN95 | VFAT_SFN_CREATE_WIN95:
788 seq_puts(m, ",shortname=win95");
790 case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WINNT:
791 seq_puts(m, ",shortname=winnt");
793 case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WIN95:
794 seq_puts(m, ",shortname=mixed");
796 case VFAT_SFN_DISPLAY_LOWER | VFAT_SFN_CREATE_WIN95:
797 seq_puts(m, ",shortname=lower");
800 seq_puts(m, ",shortname=unknown");
804 if (opts->name_check != 'n')
805 seq_printf(m, ",check=%c", opts->name_check);
807 seq_puts(m, ",usefree");
809 seq_puts(m, ",quiet");
811 seq_puts(m, ",showexec");
812 if (opts->sys_immutable)
813 seq_puts(m, ",sys_immutable");
816 seq_puts(m, ",dotsOK=yes");
818 seq_puts(m, ",nocase");
821 seq_puts(m, ",utf8");
822 if (opts->unicode_xlate)
823 seq_puts(m, ",uni_xlate");
825 seq_puts(m, ",nonumtail");
827 seq_puts(m, ",rodir");
830 seq_puts(m, ",flush");
832 if (opts->time_offset)
833 seq_printf(m, ",time_offset=%d", opts->time_offset);
835 seq_puts(m, ",tz=UTC");
837 if (opts->errors == FAT_ERRORS_CONT)
838 seq_puts(m, ",errors=continue");
839 else if (opts->errors == FAT_ERRORS_PANIC)
840 seq_puts(m, ",errors=panic");
842 seq_puts(m, ",errors=remount-ro");
843 if (opts->nfs == FAT_NFS_NOSTALE_RO)
844 seq_puts(m, ",nfs=nostale_ro");
846 seq_puts(m, ",nfs=stale_rw");
848 seq_puts(m, ",discard");
854 Opt_check_n, Opt_check_r, Opt_check_s, Opt_uid, Opt_gid,
855 Opt_umask, Opt_dmask, Opt_fmask, Opt_allow_utime, Opt_codepage,
856 Opt_usefree, Opt_nocase, Opt_quiet, Opt_showexec, Opt_debug,
857 Opt_immutable, Opt_dots, Opt_nodots,
858 Opt_charset, Opt_shortname_lower, Opt_shortname_win95,
859 Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes,
860 Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes,
861 Opt_obsolete, Opt_flush, Opt_tz_utc, Opt_rodir, Opt_err_cont,
862 Opt_err_panic, Opt_err_ro, Opt_discard, Opt_nfs, Opt_time_offset,
863 Opt_nfs_stale_rw, Opt_nfs_nostale_ro, Opt_err,
866 static const match_table_t fat_tokens = {
867 {Opt_check_r, "check=relaxed"},
868 {Opt_check_s, "check=strict"},
869 {Opt_check_n, "check=normal"},
870 {Opt_check_r, "check=r"},
871 {Opt_check_s, "check=s"},
872 {Opt_check_n, "check=n"},
875 {Opt_umask, "umask=%o"},
876 {Opt_dmask, "dmask=%o"},
877 {Opt_fmask, "fmask=%o"},
878 {Opt_allow_utime, "allow_utime=%o"},
879 {Opt_codepage, "codepage=%u"},
880 {Opt_usefree, "usefree"},
881 {Opt_nocase, "nocase"},
882 {Opt_quiet, "quiet"},
883 {Opt_showexec, "showexec"},
884 {Opt_debug, "debug"},
885 {Opt_immutable, "sys_immutable"},
886 {Opt_flush, "flush"},
887 {Opt_tz_utc, "tz=UTC"},
888 {Opt_time_offset, "time_offset=%d"},
889 {Opt_err_cont, "errors=continue"},
890 {Opt_err_panic, "errors=panic"},
891 {Opt_err_ro, "errors=remount-ro"},
892 {Opt_discard, "discard"},
893 {Opt_nfs_stale_rw, "nfs"},
894 {Opt_nfs_stale_rw, "nfs=stale_rw"},
895 {Opt_nfs_nostale_ro, "nfs=nostale_ro"},
896 {Opt_obsolete, "conv=binary"},
897 {Opt_obsolete, "conv=text"},
898 {Opt_obsolete, "conv=auto"},
899 {Opt_obsolete, "conv=b"},
900 {Opt_obsolete, "conv=t"},
901 {Opt_obsolete, "conv=a"},
902 {Opt_obsolete, "fat=%u"},
903 {Opt_obsolete, "blocksize=%u"},
904 {Opt_obsolete, "cvf_format=%20s"},
905 {Opt_obsolete, "cvf_options=%100s"},
906 {Opt_obsolete, "posix"},
909 static const match_table_t msdos_tokens = {
910 {Opt_nodots, "nodots"},
911 {Opt_nodots, "dotsOK=no"},
913 {Opt_dots, "dotsOK=yes"},
916 static const match_table_t vfat_tokens = {
917 {Opt_charset, "iocharset=%s"},
918 {Opt_shortname_lower, "shortname=lower"},
919 {Opt_shortname_win95, "shortname=win95"},
920 {Opt_shortname_winnt, "shortname=winnt"},
921 {Opt_shortname_mixed, "shortname=mixed"},
922 {Opt_utf8_no, "utf8=0"}, /* 0 or no or false */
923 {Opt_utf8_no, "utf8=no"},
924 {Opt_utf8_no, "utf8=false"},
925 {Opt_utf8_yes, "utf8=1"}, /* empty or 1 or yes or true */
926 {Opt_utf8_yes, "utf8=yes"},
927 {Opt_utf8_yes, "utf8=true"},
928 {Opt_utf8_yes, "utf8"},
929 {Opt_uni_xl_no, "uni_xlate=0"}, /* 0 or no or false */
930 {Opt_uni_xl_no, "uni_xlate=no"},
931 {Opt_uni_xl_no, "uni_xlate=false"},
932 {Opt_uni_xl_yes, "uni_xlate=1"}, /* empty or 1 or yes or true */
933 {Opt_uni_xl_yes, "uni_xlate=yes"},
934 {Opt_uni_xl_yes, "uni_xlate=true"},
935 {Opt_uni_xl_yes, "uni_xlate"},
936 {Opt_nonumtail_no, "nonumtail=0"}, /* 0 or no or false */
937 {Opt_nonumtail_no, "nonumtail=no"},
938 {Opt_nonumtail_no, "nonumtail=false"},
939 {Opt_nonumtail_yes, "nonumtail=1"}, /* empty or 1 or yes or true */
940 {Opt_nonumtail_yes, "nonumtail=yes"},
941 {Opt_nonumtail_yes, "nonumtail=true"},
942 {Opt_nonumtail_yes, "nonumtail"},
943 {Opt_rodir, "rodir"},
947 static int parse_options(struct super_block *sb, char *options, int is_vfat,
948 int silent, int *debug, struct fat_mount_options *opts)
951 substring_t args[MAX_OPT_ARGS];
955 opts->isvfat = is_vfat;
957 opts->fs_uid = current_uid();
958 opts->fs_gid = current_gid();
959 opts->fs_fmask = opts->fs_dmask = current_umask();
960 opts->allow_utime = -1;
961 opts->codepage = fat_default_codepage;
962 opts->iocharset = fat_default_iocharset;
964 opts->shortname = VFAT_SFN_DISPLAY_WINNT|VFAT_SFN_CREATE_WIN95;
970 opts->name_check = 'n';
971 opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK = 0;
972 opts->utf8 = opts->unicode_xlate = 0;
974 opts->usefree = opts->nocase = 0;
977 opts->errors = FAT_ERRORS_RO;
983 while ((p = strsep(&options, ",")) != NULL) {
988 token = match_token(p, fat_tokens, args);
989 if (token == Opt_err) {
991 token = match_token(p, vfat_tokens, args);
993 token = match_token(p, msdos_tokens, args);
997 opts->name_check = 's';
1000 opts->name_check = 'r';
1003 opts->name_check = 'n';
1012 /* for backward compatibility */
1013 opts->shortname = VFAT_SFN_DISPLAY_WIN95
1014 | VFAT_SFN_CREATE_WIN95;
1027 opts->sys_immutable = 1;
1030 if (match_int(&args[0], &option))
1032 opts->fs_uid = make_kuid(current_user_ns(), option);
1033 if (!uid_valid(opts->fs_uid))
1037 if (match_int(&args[0], &option))
1039 opts->fs_gid = make_kgid(current_user_ns(), option);
1040 if (!gid_valid(opts->fs_gid))
1044 if (match_octal(&args[0], &option))
1046 opts->fs_fmask = opts->fs_dmask = option;
1049 if (match_octal(&args[0], &option))
1051 opts->fs_dmask = option;
1054 if (match_octal(&args[0], &option))
1056 opts->fs_fmask = option;
1058 case Opt_allow_utime:
1059 if (match_octal(&args[0], &option))
1061 opts->allow_utime = option & (S_IWGRP | S_IWOTH);
1064 if (match_int(&args[0], &option))
1066 opts->codepage = option;
1071 case Opt_time_offset:
1072 if (match_int(&args[0], &option))
1074 if (option < -12 * 60 || option > 12 * 60)
1077 opts->time_offset = option;
1081 opts->time_offset = 0;
1084 opts->errors = FAT_ERRORS_CONT;
1087 opts->errors = FAT_ERRORS_PANIC;
1090 opts->errors = FAT_ERRORS_RO;
1092 case Opt_nfs_stale_rw:
1093 opts->nfs = FAT_NFS_STALE_RW;
1095 case Opt_nfs_nostale_ro:
1096 opts->nfs = FAT_NFS_NOSTALE_RO;
1099 /* msdos specific */
1109 if (opts->iocharset != fat_default_iocharset)
1110 kfree(opts->iocharset);
1111 iocharset = match_strdup(&args[0]);
1114 opts->iocharset = iocharset;
1116 case Opt_shortname_lower:
1117 opts->shortname = VFAT_SFN_DISPLAY_LOWER
1118 | VFAT_SFN_CREATE_WIN95;
1120 case Opt_shortname_win95:
1121 opts->shortname = VFAT_SFN_DISPLAY_WIN95
1122 | VFAT_SFN_CREATE_WIN95;
1124 case Opt_shortname_winnt:
1125 opts->shortname = VFAT_SFN_DISPLAY_WINNT
1126 | VFAT_SFN_CREATE_WINNT;
1128 case Opt_shortname_mixed:
1129 opts->shortname = VFAT_SFN_DISPLAY_WINNT
1130 | VFAT_SFN_CREATE_WIN95;
1132 case Opt_utf8_no: /* 0 or no or false */
1135 case Opt_utf8_yes: /* empty or 1 or yes or true */
1138 case Opt_uni_xl_no: /* 0 or no or false */
1139 opts->unicode_xlate = 0;
1141 case Opt_uni_xl_yes: /* empty or 1 or yes or true */
1142 opts->unicode_xlate = 1;
1144 case Opt_nonumtail_no: /* 0 or no or false */
1145 opts->numtail = 1; /* negated option */
1147 case Opt_nonumtail_yes: /* empty or 1 or yes or true */
1148 opts->numtail = 0; /* negated option */
1157 /* obsolete mount options */
1159 fat_msg(sb, KERN_INFO, "\"%s\" option is obsolete, "
1160 "not supported now", p);
1162 /* unknown option */
1165 fat_msg(sb, KERN_ERR,
1166 "Unrecognized mount option \"%s\" "
1167 "or missing value", p);
1174 /* UTF-8 doesn't provide FAT semantics */
1175 if (!strcmp(opts->iocharset, "utf8")) {
1176 fat_msg(sb, KERN_WARNING, "utf8 is not a recommended IO charset"
1177 " for FAT filesystems, filesystem will be "
1181 /* If user doesn't specify allow_utime, it's initialized from dmask. */
1182 if (opts->allow_utime == (unsigned short)-1)
1183 opts->allow_utime = ~opts->fs_dmask & (S_IWGRP | S_IWOTH);
1184 if (opts->unicode_xlate)
1186 if (opts->nfs == FAT_NFS_NOSTALE_RO) {
1187 sb->s_flags |= MS_RDONLY;
1188 sb->s_export_op = &fat_export_ops_nostale;
1194 static int fat_read_root(struct inode *inode)
1196 struct super_block *sb = inode->i_sb;
1197 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1200 MSDOS_I(inode)->i_pos = MSDOS_ROOT_INO;
1201 inode->i_uid = sbi->options.fs_uid;
1202 inode->i_gid = sbi->options.fs_gid;
1204 inode->i_generation = 0;
1205 inode->i_mode = fat_make_mode(sbi, ATTR_DIR, S_IRWXUGO);
1206 inode->i_op = sbi->dir_ops;
1207 inode->i_fop = &fat_dir_operations;
1208 if (sbi->fat_bits == 32) {
1209 MSDOS_I(inode)->i_start = sbi->root_cluster;
1210 error = fat_calc_dir_size(inode);
1214 MSDOS_I(inode)->i_start = 0;
1215 inode->i_size = sbi->dir_entries * sizeof(struct msdos_dir_entry);
1217 inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
1218 & ~((loff_t)sbi->cluster_size - 1)) >> 9;
1219 MSDOS_I(inode)->i_logstart = 0;
1220 MSDOS_I(inode)->mmu_private = inode->i_size;
1222 fat_save_attrs(inode, ATTR_DIR);
1223 inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0;
1224 inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = 0;
1225 set_nlink(inode, fat_subdirs(inode)+2);
1230 static unsigned long calc_fat_clusters(struct super_block *sb)
1232 struct msdos_sb_info *sbi = MSDOS_SB(sb);
1234 /* Divide first to avoid overflow */
1235 if (sbi->fat_bits != 12) {
1236 unsigned long ent_per_sec = sb->s_blocksize * 8 / sbi->fat_bits;
1237 return ent_per_sec * sbi->fat_length;
1240 return sbi->fat_length * sb->s_blocksize * 8 / sbi->fat_bits;
1244 * Read the super block of an MS-DOS FS.
1246 int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat,
1247 void (*setup)(struct super_block *))
1249 struct inode *root_inode = NULL, *fat_inode = NULL;
1250 struct inode *fsinfo_inode = NULL;
1251 struct buffer_head *bh;
1252 struct fat_boot_sector *b;
1253 struct msdos_sb_info *sbi;
1254 u16 logical_sector_size;
1255 u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors;
1262 * GFP_KERNEL is ok here, because while we do hold the
1263 * supeblock lock, memory pressure can't call back into
1264 * the filesystem, since we're only just about to mount
1265 * it and have no inodes etc active!
1267 sbi = kzalloc(sizeof(struct msdos_sb_info), GFP_KERNEL);
1270 sb->s_fs_info = sbi;
1272 sb->s_flags |= MS_NODIRATIME;
1273 sb->s_magic = MSDOS_SUPER_MAGIC;
1274 sb->s_op = &fat_sops;
1275 sb->s_export_op = &fat_export_ops;
1276 mutex_init(&sbi->nfs_build_inode_lock);
1277 ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL,
1278 DEFAULT_RATELIMIT_BURST);
1280 error = parse_options(sb, data, isvfat, silent, &debug, &sbi->options);
1284 setup(sb); /* flavour-specific stuff that needs options */
1287 sb_min_blocksize(sb, 512);
1288 bh = sb_bread(sb, 0);
1290 fat_msg(sb, KERN_ERR, "unable to read boot sector");
1294 b = (struct fat_boot_sector *) bh->b_data;
1297 fat_msg(sb, KERN_ERR, "bogus number of reserved sectors");
1303 fat_msg(sb, KERN_ERR, "bogus number of FAT structure");
1309 * Earlier we checked here that b->secs_track and b->head are nonzero,
1310 * but it turns out valid FAT filesystems can have zero there.
1314 if (!fat_valid_media(media)) {
1316 fat_msg(sb, KERN_ERR, "invalid media value (0x%02x)",
1321 logical_sector_size = get_unaligned_le16(&b->sector_size);
1322 if (!is_power_of_2(logical_sector_size)
1323 || (logical_sector_size < 512)
1324 || (logical_sector_size > 4096)) {
1326 fat_msg(sb, KERN_ERR, "bogus logical sector size %u",
1327 logical_sector_size);
1331 sbi->sec_per_clus = b->sec_per_clus;
1332 if (!is_power_of_2(sbi->sec_per_clus)) {
1334 fat_msg(sb, KERN_ERR, "bogus sectors per cluster %u",
1340 if (logical_sector_size < sb->s_blocksize) {
1341 fat_msg(sb, KERN_ERR, "logical sector size too small for device"
1342 " (logical sector size = %u)", logical_sector_size);
1346 if (logical_sector_size > sb->s_blocksize) {
1349 if (!sb_set_blocksize(sb, logical_sector_size)) {
1350 fat_msg(sb, KERN_ERR, "unable to set blocksize %u",
1351 logical_sector_size);
1354 bh = sb_bread(sb, 0);
1356 fat_msg(sb, KERN_ERR, "unable to read boot sector"
1357 " (logical sector size = %lu)",
1361 b = (struct fat_boot_sector *) bh->b_data;
1364 mutex_init(&sbi->s_lock);
1365 sbi->cluster_size = sb->s_blocksize * sbi->sec_per_clus;
1366 sbi->cluster_bits = ffs(sbi->cluster_size) - 1;
1367 sbi->fats = b->fats;
1368 sbi->fat_bits = 0; /* Don't know yet */
1369 sbi->fat_start = le16_to_cpu(b->reserved);
1370 sbi->fat_length = le16_to_cpu(b->fat_length);
1371 sbi->root_cluster = 0;
1372 sbi->free_clusters = -1; /* Don't know yet */
1373 sbi->free_clus_valid = 0;
1374 sbi->prev_free = FAT_START_ENT;
1375 sb->s_maxbytes = 0xffffffff;
1377 if (!sbi->fat_length && b->fat32.length) {
1378 struct fat_boot_fsinfo *fsinfo;
1379 struct buffer_head *fsinfo_bh;
1383 sbi->fat_length = le32_to_cpu(b->fat32.length);
1384 sbi->root_cluster = le32_to_cpu(b->fat32.root_cluster);
1386 /* MC - if info_sector is 0, don't multiply by 0 */
1387 sbi->fsinfo_sector = le16_to_cpu(b->fat32.info_sector);
1388 if (sbi->fsinfo_sector == 0)
1389 sbi->fsinfo_sector = 1;
1391 fsinfo_bh = sb_bread(sb, sbi->fsinfo_sector);
1392 if (fsinfo_bh == NULL) {
1393 fat_msg(sb, KERN_ERR, "bread failed, FSINFO block"
1394 " (sector = %lu)", sbi->fsinfo_sector);
1399 fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data;
1400 if (!IS_FSINFO(fsinfo)) {
1401 fat_msg(sb, KERN_WARNING, "Invalid FSINFO signature: "
1402 "0x%08x, 0x%08x (sector = %lu)",
1403 le32_to_cpu(fsinfo->signature1),
1404 le32_to_cpu(fsinfo->signature2),
1405 sbi->fsinfo_sector);
1407 if (sbi->options.usefree)
1408 sbi->free_clus_valid = 1;
1409 sbi->free_clusters = le32_to_cpu(fsinfo->free_clusters);
1410 sbi->prev_free = le32_to_cpu(fsinfo->next_cluster);
1416 /* interpret volume ID as a little endian 32 bit integer */
1417 if (sbi->fat_bits == 32)
1418 sbi->vol_id = (((u32)b->fat32.vol_id[0]) |
1419 ((u32)b->fat32.vol_id[1] << 8) |
1420 ((u32)b->fat32.vol_id[2] << 16) |
1421 ((u32)b->fat32.vol_id[3] << 24));
1422 else /* fat 16 or 12 */
1423 sbi->vol_id = (((u32)b->fat16.vol_id[0]) |
1424 ((u32)b->fat16.vol_id[1] << 8) |
1425 ((u32)b->fat16.vol_id[2] << 16) |
1426 ((u32)b->fat16.vol_id[3] << 24));
1428 sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry);
1429 sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1;
1431 sbi->dir_start = sbi->fat_start + sbi->fats * sbi->fat_length;
1432 sbi->dir_entries = get_unaligned_le16(&b->dir_entries);
1433 if (sbi->dir_entries & (sbi->dir_per_block - 1)) {
1435 fat_msg(sb, KERN_ERR, "bogus directory-entries per block"
1436 " (%u)", sbi->dir_entries);
1441 rootdir_sectors = sbi->dir_entries
1442 * sizeof(struct msdos_dir_entry) / sb->s_blocksize;
1443 sbi->data_start = sbi->dir_start + rootdir_sectors;
1444 total_sectors = get_unaligned_le16(&b->sectors);
1445 if (total_sectors == 0)
1446 total_sectors = le32_to_cpu(b->total_sect);
1448 total_clusters = (total_sectors - sbi->data_start) / sbi->sec_per_clus;
1450 if (sbi->fat_bits != 32)
1451 sbi->fat_bits = (total_clusters > MAX_FAT12) ? 16 : 12;
1453 /* some OSes set FAT_STATE_DIRTY and clean it on unmount. */
1454 if (sbi->fat_bits == 32)
1455 sbi->dirty = b->fat32.state & FAT_STATE_DIRTY;
1456 else /* fat 16 or 12 */
1457 sbi->dirty = b->fat16.state & FAT_STATE_DIRTY;
1459 /* check that FAT table does not overflow */
1460 fat_clusters = calc_fat_clusters(sb);
1461 total_clusters = min(total_clusters, fat_clusters - FAT_START_ENT);
1462 if (total_clusters > MAX_FAT(sb)) {
1464 fat_msg(sb, KERN_ERR, "count of clusters too big (%u)",
1470 sbi->max_cluster = total_clusters + FAT_START_ENT;
1471 /* check the free_clusters, it's not necessarily correct */
1472 if (sbi->free_clusters != -1 && sbi->free_clusters > total_clusters)
1473 sbi->free_clusters = -1;
1474 /* check the prev_free, it's not necessarily correct */
1475 sbi->prev_free %= sbi->max_cluster;
1476 if (sbi->prev_free < FAT_START_ENT)
1477 sbi->prev_free = FAT_START_ENT;
1481 /* set up enough so that it can read an inode */
1484 fat_ent_access_init(sb);
1487 * The low byte of FAT's first entry must have same value with
1488 * media-field. But in real world, too many devices is
1489 * writing wrong value. So, removed that validity check.
1491 * if (FAT_FIRST_ENT(sb, media) != first)
1495 sprintf(buf, "cp%d", sbi->options.codepage);
1496 sbi->nls_disk = load_nls(buf);
1497 if (!sbi->nls_disk) {
1498 fat_msg(sb, KERN_ERR, "codepage %s not found", buf);
1502 /* FIXME: utf8 is using iocharset for upper/lower conversion */
1503 if (sbi->options.isvfat) {
1504 sbi->nls_io = load_nls(sbi->options.iocharset);
1506 fat_msg(sb, KERN_ERR, "IO charset %s not found",
1507 sbi->options.iocharset);
1513 fat_inode = new_inode(sb);
1516 MSDOS_I(fat_inode)->i_pos = 0;
1517 sbi->fat_inode = fat_inode;
1519 fsinfo_inode = new_inode(sb);
1522 fsinfo_inode->i_ino = MSDOS_FSINFO_INO;
1523 sbi->fsinfo_inode = fsinfo_inode;
1524 insert_inode_hash(fsinfo_inode);
1526 root_inode = new_inode(sb);
1529 root_inode->i_ino = MSDOS_ROOT_INO;
1530 root_inode->i_version = 1;
1531 error = fat_read_root(root_inode);
1537 insert_inode_hash(root_inode);
1538 fat_attach(root_inode, 0);
1539 sb->s_root = d_make_root(root_inode);
1541 fat_msg(sb, KERN_ERR, "get root inode failed");
1545 if (sbi->options.discard) {
1546 struct request_queue *q = bdev_get_queue(sb->s_bdev);
1547 if (!blk_queue_discard(q))
1548 fat_msg(sb, KERN_WARNING,
1549 "mounting with \"discard\" option, but "
1550 "the device does not support discard");
1553 fat_set_state(sb, 1, 0);
1559 fat_msg(sb, KERN_INFO, "Can't find a valid FAT filesystem");
1566 unload_nls(sbi->nls_io);
1567 unload_nls(sbi->nls_disk);
1568 if (sbi->options.iocharset != fat_default_iocharset)
1569 kfree(sbi->options.iocharset);
1570 sb->s_fs_info = NULL;
1575 EXPORT_SYMBOL_GPL(fat_fill_super);
1578 * helper function for fat_flush_inodes. This writes both the inode
1579 * and the file data blocks, waiting for in flight data blocks before
1580 * the start of the call. It does not wait for any io started
1583 static int writeback_inode(struct inode *inode)
1588 /* if we used wait=1, sync_inode_metadata waits for the io for the
1589 * inode to finish. So wait=0 is sent down to sync_inode_metadata
1590 * and filemap_fdatawrite is used for the data blocks
1592 ret = sync_inode_metadata(inode, 0);
1594 ret = filemap_fdatawrite(inode->i_mapping);
1599 * write data and metadata corresponding to i1 and i2. The io is
1600 * started but we do not wait for any of it to finish.
1602 * filemap_flush is used for the block device, so if there is a dirty
1603 * page for a block already in flight, we will not wait and start the
1606 int fat_flush_inodes(struct super_block *sb, struct inode *i1, struct inode *i2)
1609 if (!MSDOS_SB(sb)->options.flush)
1612 ret = writeback_inode(i1);
1614 ret = writeback_inode(i2);
1616 struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
1617 ret = filemap_flush(mapping);
1621 EXPORT_SYMBOL_GPL(fat_flush_inodes);
1623 static int __init init_fat_fs(void)
1627 err = fat_cache_init();
1631 err = fat_init_inodecache();
1638 fat_cache_destroy();
1642 static void __exit exit_fat_fs(void)
1644 fat_cache_destroy();
1645 fat_destroy_inodecache();
1648 module_init(init_fat_fs)
1649 module_exit(exit_fat_fs)
1651 MODULE_LICENSE("GPL");