summaryrefslogtreecommitdiff
path: root/fs/fat/inode.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /fs/fat/inode.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'fs/fat/inode.c')
-rw-r--r--fs/fat/inode.c1351
1 files changed, 1351 insertions, 0 deletions
diff --git a/fs/fat/inode.c b/fs/fat/inode.c
new file mode 100644
index 000000000000..8ccee8415488
--- /dev/null
+++ b/fs/fat/inode.c
@@ -0,0 +1,1351 @@
+/*
+ * linux/fs/fat/inode.c
+ *
+ * Written 1992,1993 by Werner Almesberger
+ * VFAT extensions by Gordon Chaffee, merged with msdos fs by Henrik Storner
+ * Rewritten for the constant inumbers support by Al Viro
+ *
+ * Fixes:
+ *
+ * Max Cohan: Fixed invalid FSINFO offset when info_sector is 0
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/slab.h>
+#include <linux/smp_lock.h>
+#include <linux/seq_file.h>
+#include <linux/msdos_fs.h>
+#include <linux/pagemap.h>
+#include <linux/buffer_head.h>
+#include <linux/mount.h>
+#include <linux/vfs.h>
+#include <linux/parser.h>
+#include <asm/unaligned.h>
+
+#ifndef CONFIG_FAT_DEFAULT_IOCHARSET
+/* if user don't select VFAT, this is undefined. */
+#define CONFIG_FAT_DEFAULT_IOCHARSET ""
+#endif
+
+static int fat_default_codepage = CONFIG_FAT_DEFAULT_CODEPAGE;
+static char fat_default_iocharset[] = CONFIG_FAT_DEFAULT_IOCHARSET;
+
+
+static int fat_add_cluster(struct inode *inode)
+{
+ int err, cluster;
+
+ err = fat_alloc_clusters(inode, &cluster, 1);
+ if (err)
+ return err;
+ /* FIXME: this cluster should be added after data of this
+ * cluster is writed */
+ err = fat_chain_add(inode, cluster, 1);
+ if (err)
+ fat_free_clusters(inode, cluster);
+ return err;
+}
+
+static int fat_get_block(struct inode *inode, sector_t iblock,
+ struct buffer_head *bh_result, int create)
+{
+ struct super_block *sb = inode->i_sb;
+ sector_t phys;
+ int err;
+
+ err = fat_bmap(inode, iblock, &phys);
+ if (err)
+ return err;
+ if (phys) {
+ map_bh(bh_result, sb, phys);
+ return 0;
+ }
+ if (!create)
+ return 0;
+ if (iblock != MSDOS_I(inode)->mmu_private >> sb->s_blocksize_bits) {
+ fat_fs_panic(sb, "corrupted file size (i_pos %lld, %lld)",
+ MSDOS_I(inode)->i_pos, MSDOS_I(inode)->mmu_private);
+ return -EIO;
+ }
+ if (!((unsigned long)iblock & (MSDOS_SB(sb)->sec_per_clus - 1))) {
+ err = fat_add_cluster(inode);
+ if (err)
+ return err;
+ }
+ MSDOS_I(inode)->mmu_private += sb->s_blocksize;
+ err = fat_bmap(inode, iblock, &phys);
+ if (err)
+ return err;
+ if (!phys)
+ BUG();
+ set_buffer_new(bh_result);
+ map_bh(bh_result, sb, phys);
+ return 0;
+}
+
+static int fat_writepage(struct page *page, struct writeback_control *wbc)
+{
+ return block_write_full_page(page, fat_get_block, wbc);
+}
+
+static int fat_readpage(struct file *file, struct page *page)
+{
+ return block_read_full_page(page, fat_get_block);
+}
+
+static int fat_prepare_write(struct file *file, struct page *page,
+ unsigned from, unsigned to)
+{
+ return cont_prepare_write(page, from, to, fat_get_block,
+ &MSDOS_I(page->mapping->host)->mmu_private);
+}
+
+static sector_t _fat_bmap(struct address_space *mapping, sector_t block)
+{
+ return generic_block_bmap(mapping, block, fat_get_block);
+}
+
+static struct address_space_operations fat_aops = {
+ .readpage = fat_readpage,
+ .writepage = fat_writepage,
+ .sync_page = block_sync_page,
+ .prepare_write = fat_prepare_write,
+ .commit_write = generic_commit_write,
+ .bmap = _fat_bmap
+};
+
+/*
+ * New FAT inode stuff. We do the following:
+ * a) i_ino is constant and has nothing with on-disk location.
+ * b) FAT manages its own cache of directory entries.
+ * c) *This* cache is indexed by on-disk location.
+ * d) inode has an associated directory entry, all right, but
+ * it may be unhashed.
+ * e) currently entries are stored within struct inode. That should
+ * change.
+ * f) we deal with races in the following way:
+ * 1. readdir() and lookup() do FAT-dir-cache lookup.
+ * 2. rename() unhashes the F-d-c entry and rehashes it in
+ * a new place.
+ * 3. unlink() and rmdir() unhash F-d-c entry.
+ * 4. fat_write_inode() checks whether the thing is unhashed.
+ * If it is we silently return. If it isn't we do bread(),
+ * check if the location is still valid and retry if it
+ * isn't. Otherwise we do changes.
+ * 5. Spinlock is used to protect hash/unhash/location check/lookup
+ * 6. fat_clear_inode() unhashes the F-d-c entry.
+ * 7. lookup() and readdir() do igrab() if they find a F-d-c entry
+ * and consider negative result as cache miss.
+ */
+
+static void fat_hash_init(struct super_block *sb)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(sb);
+ int i;
+
+ spin_lock_init(&sbi->inode_hash_lock);
+ for (i = 0; i < FAT_HASH_SIZE; i++)
+ INIT_HLIST_HEAD(&sbi->inode_hashtable[i]);
+}
+
+static inline unsigned long fat_hash(struct super_block *sb, loff_t i_pos)
+{
+ unsigned long tmp = (unsigned long)i_pos | (unsigned long) sb;
+ tmp = tmp + (tmp >> FAT_HASH_BITS) + (tmp >> FAT_HASH_BITS * 2);
+ return tmp & FAT_HASH_MASK;
+}
+
+void fat_attach(struct inode *inode, loff_t i_pos)
+{
+ struct super_block *sb = inode->i_sb;
+ struct msdos_sb_info *sbi = MSDOS_SB(sb);
+
+ spin_lock(&sbi->inode_hash_lock);
+ MSDOS_I(inode)->i_pos = i_pos;
+ hlist_add_head(&MSDOS_I(inode)->i_fat_hash,
+ sbi->inode_hashtable + fat_hash(sb, i_pos));
+ spin_unlock(&sbi->inode_hash_lock);
+}
+
+EXPORT_SYMBOL(fat_attach);
+
+void fat_detach(struct inode *inode)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+ spin_lock(&sbi->inode_hash_lock);
+ MSDOS_I(inode)->i_pos = 0;
+ hlist_del_init(&MSDOS_I(inode)->i_fat_hash);
+ spin_unlock(&sbi->inode_hash_lock);
+}
+
+EXPORT_SYMBOL(fat_detach);
+
+struct inode *fat_iget(struct super_block *sb, loff_t i_pos)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(sb);
+ struct hlist_head *head = sbi->inode_hashtable + fat_hash(sb, i_pos);
+ struct hlist_node *_p;
+ struct msdos_inode_info *i;
+ struct inode *inode = NULL;
+
+ spin_lock(&sbi->inode_hash_lock);
+ hlist_for_each_entry(i, _p, head, i_fat_hash) {
+ BUG_ON(i->vfs_inode.i_sb != sb);
+ if (i->i_pos != i_pos)
+ continue;
+ inode = igrab(&i->vfs_inode);
+ if (inode)
+ break;
+ }
+ spin_unlock(&sbi->inode_hash_lock);
+ return inode;
+}
+
+static int is_exec(unsigned char *extension)
+{
+ unsigned char *exe_extensions = "EXECOMBAT", *walk;
+
+ for (walk = exe_extensions; *walk; walk += 3)
+ if (!strncmp(extension, walk, 3))
+ return 1;
+ return 0;
+}
+
+static int fat_calc_dir_size(struct inode *inode)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+ int ret, fclus, dclus;
+
+ inode->i_size = 0;
+ if (MSDOS_I(inode)->i_start == 0)
+ return 0;
+
+ ret = fat_get_cluster(inode, FAT_ENT_EOF, &fclus, &dclus);
+ if (ret < 0)
+ return ret;
+ inode->i_size = (fclus + 1) << sbi->cluster_bits;
+
+ return 0;
+}
+
+/* doesn't deal with root inode */
+static int fat_fill_inode(struct inode *inode, struct msdos_dir_entry *de)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+ int error;
+
+ MSDOS_I(inode)->i_pos = 0;
+ inode->i_uid = sbi->options.fs_uid;
+ inode->i_gid = sbi->options.fs_gid;
+ inode->i_version++;
+ inode->i_generation = get_seconds();
+
+ if ((de->attr & ATTR_DIR) && !IS_FREE(de->name)) {
+ inode->i_generation &= ~1;
+ inode->i_mode = MSDOS_MKMODE(de->attr,
+ S_IRWXUGO & ~sbi->options.fs_dmask) | S_IFDIR;
+ inode->i_op = sbi->dir_ops;
+ inode->i_fop = &fat_dir_operations;
+
+ MSDOS_I(inode)->i_start = le16_to_cpu(de->start);
+ if (sbi->fat_bits == 32)
+ MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16);
+
+ MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
+ error = fat_calc_dir_size(inode);
+ if (error < 0)
+ return error;
+ MSDOS_I(inode)->mmu_private = inode->i_size;
+
+ inode->i_nlink = fat_subdirs(inode);
+ } else { /* not a directory */
+ inode->i_generation |= 1;
+ inode->i_mode = MSDOS_MKMODE(de->attr,
+ ((sbi->options.showexec &&
+ !is_exec(de->ext))
+ ? S_IRUGO|S_IWUGO : S_IRWXUGO)
+ & ~sbi->options.fs_fmask) | S_IFREG;
+ MSDOS_I(inode)->i_start = le16_to_cpu(de->start);
+ if (sbi->fat_bits == 32)
+ MSDOS_I(inode)->i_start |= (le16_to_cpu(de->starthi) << 16);
+
+ MSDOS_I(inode)->i_logstart = MSDOS_I(inode)->i_start;
+ inode->i_size = le32_to_cpu(de->size);
+ inode->i_op = &fat_file_inode_operations;
+ inode->i_fop = &fat_file_operations;
+ inode->i_mapping->a_ops = &fat_aops;
+ MSDOS_I(inode)->mmu_private = inode->i_size;
+ }
+ if (de->attr & ATTR_SYS) {
+ if (sbi->options.sys_immutable)
+ inode->i_flags |= S_IMMUTABLE;
+ }
+ MSDOS_I(inode)->i_attrs = de->attr & ATTR_UNUSED;
+ /* this is as close to the truth as we can get ... */
+ inode->i_blksize = sbi->cluster_size;
+ inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
+ & ~((loff_t)sbi->cluster_size - 1)) >> 9;
+ inode->i_mtime.tv_sec = inode->i_atime.tv_sec =
+ date_dos2unix(le16_to_cpu(de->time), le16_to_cpu(de->date));
+ inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = 0;
+ if (sbi->options.isvfat) {
+ int secs = de->ctime_cs / 100;
+ int csecs = de->ctime_cs % 100;
+ inode->i_ctime.tv_sec =
+ date_dos2unix(le16_to_cpu(de->ctime),
+ le16_to_cpu(de->cdate)) + secs;
+ inode->i_ctime.tv_nsec = csecs * 10000000;
+ } else
+ inode->i_ctime = inode->i_mtime;
+
+ return 0;
+}
+
+struct inode *fat_build_inode(struct super_block *sb,
+ struct msdos_dir_entry *de, loff_t i_pos)
+{
+ struct inode *inode;
+ int err;
+
+ inode = fat_iget(sb, i_pos);
+ if (inode)
+ goto out;
+ inode = new_inode(sb);
+ if (!inode) {
+ inode = ERR_PTR(-ENOMEM);
+ goto out;
+ }
+ inode->i_ino = iunique(sb, MSDOS_ROOT_INO);
+ inode->i_version = 1;
+ err = fat_fill_inode(inode, de);
+ if (err) {
+ iput(inode);
+ inode = ERR_PTR(err);
+ goto out;
+ }
+ fat_attach(inode, i_pos);
+ insert_inode_hash(inode);
+out:
+ return inode;
+}
+
+EXPORT_SYMBOL(fat_build_inode);
+
+static void fat_delete_inode(struct inode *inode)
+{
+ if (!is_bad_inode(inode)) {
+ inode->i_size = 0;
+ fat_truncate(inode);
+ }
+ clear_inode(inode);
+}
+
+static void fat_clear_inode(struct inode *inode)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+
+ if (is_bad_inode(inode))
+ return;
+ lock_kernel();
+ spin_lock(&sbi->inode_hash_lock);
+ fat_cache_inval_inode(inode);
+ hlist_del_init(&MSDOS_I(inode)->i_fat_hash);
+ spin_unlock(&sbi->inode_hash_lock);
+ unlock_kernel();
+}
+
+static void fat_put_super(struct super_block *sb)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(sb);
+
+ if (!(sb->s_flags & MS_RDONLY))
+ fat_clusters_flush(sb);
+
+ if (sbi->nls_disk) {
+ unload_nls(sbi->nls_disk);
+ sbi->nls_disk = NULL;
+ sbi->options.codepage = fat_default_codepage;
+ }
+ if (sbi->nls_io) {
+ unload_nls(sbi->nls_io);
+ sbi->nls_io = NULL;
+ }
+ if (sbi->options.iocharset != fat_default_iocharset) {
+ kfree(sbi->options.iocharset);
+ sbi->options.iocharset = fat_default_iocharset;
+ }
+
+ sb->s_fs_info = NULL;
+ kfree(sbi);
+}
+
+static kmem_cache_t *fat_inode_cachep;
+
+static struct inode *fat_alloc_inode(struct super_block *sb)
+{
+ struct msdos_inode_info *ei;
+ ei = kmem_cache_alloc(fat_inode_cachep, SLAB_KERNEL);
+ if (!ei)
+ return NULL;
+ return &ei->vfs_inode;
+}
+
+static void fat_destroy_inode(struct inode *inode)
+{
+ kmem_cache_free(fat_inode_cachep, MSDOS_I(inode));
+}
+
+static void init_once(void * foo, kmem_cache_t * cachep, unsigned long flags)
+{
+ struct msdos_inode_info *ei = (struct msdos_inode_info *)foo;
+
+ if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
+ SLAB_CTOR_CONSTRUCTOR) {
+ spin_lock_init(&ei->cache_lru_lock);
+ ei->nr_caches = 0;
+ ei->cache_valid_id = FAT_CACHE_VALID + 1;
+ INIT_LIST_HEAD(&ei->cache_lru);
+ INIT_HLIST_NODE(&ei->i_fat_hash);
+ inode_init_once(&ei->vfs_inode);
+ }
+}
+
+static int __init fat_init_inodecache(void)
+{
+ fat_inode_cachep = kmem_cache_create("fat_inode_cache",
+ sizeof(struct msdos_inode_info),
+ 0, SLAB_RECLAIM_ACCOUNT,
+ init_once, NULL);
+ if (fat_inode_cachep == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
+static void __exit fat_destroy_inodecache(void)
+{
+ if (kmem_cache_destroy(fat_inode_cachep))
+ printk(KERN_INFO "fat_inode_cache: not all structures were freed\n");
+}
+
+static int fat_remount(struct super_block *sb, int *flags, char *data)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(sb);
+ *flags |= MS_NODIRATIME | (sbi->options.isvfat ? 0 : MS_NOATIME);
+ return 0;
+}
+
+static int fat_statfs(struct super_block *sb, struct kstatfs *buf)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(sb);
+
+ /* If the count of free cluster is still unknown, counts it here. */
+ if (sbi->free_clusters == -1) {
+ int err = fat_count_free_clusters(sb);
+ if (err)
+ return err;
+ }
+
+ buf->f_type = sb->s_magic;
+ buf->f_bsize = sbi->cluster_size;
+ buf->f_blocks = sbi->max_cluster - FAT_START_ENT;
+ buf->f_bfree = sbi->free_clusters;
+ buf->f_bavail = sbi->free_clusters;
+ buf->f_namelen = sbi->options.isvfat ? 260 : 12;
+
+ return 0;
+}
+
+static int fat_write_inode(struct inode *inode, int wait)
+{
+ struct super_block *sb = inode->i_sb;
+ struct msdos_sb_info *sbi = MSDOS_SB(sb);
+ struct buffer_head *bh;
+ struct msdos_dir_entry *raw_entry;
+ loff_t i_pos;
+ int err = 0;
+
+retry:
+ i_pos = MSDOS_I(inode)->i_pos;
+ if (inode->i_ino == MSDOS_ROOT_INO || !i_pos)
+ return 0;
+
+ lock_kernel();
+ bh = sb_bread(sb, i_pos >> sbi->dir_per_block_bits);
+ if (!bh) {
+ printk(KERN_ERR "FAT: unable to read inode block "
+ "for updating (i_pos %lld)\n", i_pos);
+ err = -EIO;
+ goto out;
+ }
+ spin_lock(&sbi->inode_hash_lock);
+ if (i_pos != MSDOS_I(inode)->i_pos) {
+ spin_unlock(&sbi->inode_hash_lock);
+ brelse(bh);
+ unlock_kernel();
+ goto retry;
+ }
+
+ raw_entry = &((struct msdos_dir_entry *) (bh->b_data))
+ [i_pos & (sbi->dir_per_block - 1)];
+ if (S_ISDIR(inode->i_mode))
+ raw_entry->size = 0;
+ else
+ raw_entry->size = cpu_to_le32(inode->i_size);
+ raw_entry->attr = fat_attr(inode);
+ raw_entry->start = cpu_to_le16(MSDOS_I(inode)->i_logstart);
+ raw_entry->starthi = cpu_to_le16(MSDOS_I(inode)->i_logstart >> 16);
+ fat_date_unix2dos(inode->i_mtime.tv_sec, &raw_entry->time, &raw_entry->date);
+ if (sbi->options.isvfat) {
+ fat_date_unix2dos(inode->i_ctime.tv_sec,&raw_entry->ctime,&raw_entry->cdate);
+ raw_entry->ctime_cs = (inode->i_ctime.tv_sec & 1) * 100 +
+ inode->i_ctime.tv_nsec / 10000000;
+ }
+ spin_unlock(&sbi->inode_hash_lock);
+ mark_buffer_dirty(bh);
+ if (wait)
+ err = sync_dirty_buffer(bh);
+ brelse(bh);
+out:
+ unlock_kernel();
+ return err;
+}
+
+int fat_sync_inode(struct inode *inode)
+{
+ return fat_write_inode(inode, 1);
+}
+
+EXPORT_SYMBOL(fat_sync_inode);
+
+static int fat_show_options(struct seq_file *m, struct vfsmount *mnt);
+static struct super_operations fat_sops = {
+ .alloc_inode = fat_alloc_inode,
+ .destroy_inode = fat_destroy_inode,
+ .write_inode = fat_write_inode,
+ .delete_inode = fat_delete_inode,
+ .put_super = fat_put_super,
+ .statfs = fat_statfs,
+ .clear_inode = fat_clear_inode,
+ .remount_fs = fat_remount,
+
+ .read_inode = make_bad_inode,
+
+ .show_options = fat_show_options,
+};
+
+/*
+ * a FAT file handle with fhtype 3 is
+ * 0/ i_ino - for fast, reliable lookup if still in the cache
+ * 1/ i_generation - to see if i_ino is still valid
+ * bit 0 == 0 iff directory
+ * 2/ i_pos(8-39) - if ino has changed, but still in cache
+ * 3/ i_pos(4-7)|i_logstart - to semi-verify inode found at i_pos
+ * 4/ i_pos(0-3)|parent->i_logstart - maybe used to hunt for the file on disc
+ *
+ * Hack for NFSv2: Maximum FAT entry number is 28bits and maximum
+ * i_pos is 40bits (blocknr(32) + dir offset(8)), so two 4bits
+ * of i_logstart is used to store the directory entry offset.
+ */
+
+static struct dentry *
+fat_decode_fh(struct super_block *sb, __u32 *fh, int len, int fhtype,
+ int (*acceptable)(void *context, struct dentry *de),
+ void *context)
+{
+ if (fhtype != 3)
+ return ERR_PTR(-ESTALE);
+ if (len < 5)
+ return ERR_PTR(-ESTALE);
+
+ return sb->s_export_op->find_exported_dentry(sb, fh, NULL, acceptable, context);
+}
+
+static struct dentry *fat_get_dentry(struct super_block *sb, void *inump)
+{
+ struct inode *inode = NULL;
+ struct dentry *result;
+ __u32 *fh = inump;
+
+ inode = iget(sb, fh[0]);
+ if (!inode || is_bad_inode(inode) || inode->i_generation != fh[1]) {
+ if (inode)
+ iput(inode);
+ inode = NULL;
+ }
+ if (!inode) {
+ loff_t i_pos;
+ int i_logstart = fh[3] & 0x0fffffff;
+
+ i_pos = (loff_t)fh[2] << 8;
+ i_pos |= ((fh[3] >> 24) & 0xf0) | (fh[4] >> 28);
+
+ /* try 2 - see if i_pos is in F-d-c
+ * require i_logstart to be the same
+ * Will fail if you truncate and then re-write
+ */
+
+ inode = fat_iget(sb, i_pos);
+ if (inode && MSDOS_I(inode)->i_logstart != i_logstart) {
+ iput(inode);
+ inode = NULL;
+ }
+ }
+ if (!inode) {
+ /* For now, do nothing
+ * What we could do is:
+ * follow the file starting at fh[4], and record
+ * the ".." entry, and the name of the fh[2] entry.
+ * The follow the ".." file finding the next step up.
+ * This way we build a path to the root of
+ * the tree. If this works, we lookup the path and so
+ * get this inode into the cache.
+ * Finally try the fat_iget lookup again
+ * If that fails, then weare totally out of luck
+ * But all that is for another day
+ */
+ }
+ if (!inode)
+ return ERR_PTR(-ESTALE);
+
+
+ /* now to find a dentry.
+ * If possible, get a well-connected one
+ */
+ result = d_alloc_anon(inode);
+ if (result == NULL) {
+ iput(inode);
+ return ERR_PTR(-ENOMEM);
+ }
+ result->d_op = sb->s_root->d_op;
+ return result;
+}
+
+static int
+fat_encode_fh(struct dentry *de, __u32 *fh, int *lenp, int connectable)
+{
+ int len = *lenp;
+ struct inode *inode = de->d_inode;
+ u32 ipos_h, ipos_m, ipos_l;
+
+ if (len < 5)
+ return 255; /* no room */
+
+ ipos_h = MSDOS_I(inode)->i_pos >> 8;
+ ipos_m = (MSDOS_I(inode)->i_pos & 0xf0) << 24;
+ ipos_l = (MSDOS_I(inode)->i_pos & 0x0f) << 28;
+ *lenp = 5;
+ fh[0] = inode->i_ino;
+ fh[1] = inode->i_generation;
+ fh[2] = ipos_h;
+ fh[3] = ipos_m | MSDOS_I(inode)->i_logstart;
+ spin_lock(&de->d_lock);
+ fh[4] = ipos_l | MSDOS_I(de->d_parent->d_inode)->i_logstart;
+ spin_unlock(&de->d_lock);
+ return 3;
+}
+
+static struct dentry *fat_get_parent(struct dentry *child)
+{
+ struct buffer_head *bh;
+ struct msdos_dir_entry *de;
+ loff_t i_pos;
+ struct dentry *parent;
+ struct inode *inode;
+ int err;
+
+ lock_kernel();
+
+ err = fat_get_dotdot_entry(child->d_inode, &bh, &de, &i_pos);
+ if (err) {
+ parent = ERR_PTR(err);
+ goto out;
+ }
+ inode = fat_build_inode(child->d_sb, de, i_pos);
+ brelse(bh);
+ if (IS_ERR(inode)) {
+ parent = ERR_PTR(PTR_ERR(inode));
+ goto out;
+ }
+ parent = d_alloc_anon(inode);
+ if (!parent) {
+ iput(inode);
+ parent = ERR_PTR(-ENOMEM);
+ }
+out:
+ unlock_kernel();
+
+ return parent;
+}
+
+static struct export_operations fat_export_ops = {
+ .decode_fh = fat_decode_fh,
+ .encode_fh = fat_encode_fh,
+ .get_dentry = fat_get_dentry,
+ .get_parent = fat_get_parent,
+};
+
+static int fat_show_options(struct seq_file *m, struct vfsmount *mnt)
+{
+ struct msdos_sb_info *sbi = MSDOS_SB(mnt->mnt_sb);
+ struct fat_mount_options *opts = &sbi->options;
+ int isvfat = opts->isvfat;
+
+ if (opts->fs_uid != 0)
+ seq_printf(m, ",uid=%u", opts->fs_uid);
+ if (opts->fs_gid != 0)
+ seq_printf(m, ",gid=%u", opts->fs_gid);
+ seq_printf(m, ",fmask=%04o", opts->fs_fmask);
+ seq_printf(m, ",dmask=%04o", opts->fs_dmask);
+ if (sbi->nls_disk)
+ seq_printf(m, ",codepage=%s", sbi->nls_disk->charset);
+ if (isvfat) {
+ if (sbi->nls_io)
+ seq_printf(m, ",iocharset=%s", sbi->nls_io->charset);
+
+ switch (opts->shortname) {
+ case VFAT_SFN_DISPLAY_WIN95 | VFAT_SFN_CREATE_WIN95:
+ seq_puts(m, ",shortname=win95");
+ break;
+ case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WINNT:
+ seq_puts(m, ",shortname=winnt");
+ break;
+ case VFAT_SFN_DISPLAY_WINNT | VFAT_SFN_CREATE_WIN95:
+ seq_puts(m, ",shortname=mixed");
+ break;
+ case VFAT_SFN_DISPLAY_LOWER | VFAT_SFN_CREATE_WIN95:
+ /* seq_puts(m, ",shortname=lower"); */
+ break;
+ default:
+ seq_puts(m, ",shortname=unknown");
+ break;
+ }
+ }
+ if (opts->name_check != 'n')
+ seq_printf(m, ",check=%c", opts->name_check);
+ if (opts->quiet)
+ seq_puts(m, ",quiet");
+ if (opts->showexec)
+ seq_puts(m, ",showexec");
+ if (opts->sys_immutable)
+ seq_puts(m, ",sys_immutable");
+ if (!isvfat) {
+ if (opts->dotsOK)
+ seq_puts(m, ",dotsOK=yes");
+ if (opts->nocase)
+ seq_puts(m, ",nocase");
+ } else {
+ if (opts->utf8)
+ seq_puts(m, ",utf8");
+ if (opts->unicode_xlate)
+ seq_puts(m, ",uni_xlate");
+ if (!opts->numtail)
+ seq_puts(m, ",nonumtail");
+ }
+
+ return 0;
+}
+
+enum {
+ Opt_check_n, Opt_check_r, Opt_check_s, Opt_uid, Opt_gid,
+ Opt_umask, Opt_dmask, Opt_fmask, Opt_codepage, Opt_nocase,
+ Opt_quiet, Opt_showexec, Opt_debug, Opt_immutable,
+ Opt_dots, Opt_nodots,
+ Opt_charset, Opt_shortname_lower, Opt_shortname_win95,
+ Opt_shortname_winnt, Opt_shortname_mixed, Opt_utf8_no, Opt_utf8_yes,
+ Opt_uni_xl_no, Opt_uni_xl_yes, Opt_nonumtail_no, Opt_nonumtail_yes,
+ Opt_obsolate, Opt_err,
+};
+
+static match_table_t fat_tokens = {
+ {Opt_check_r, "check=relaxed"},
+ {Opt_check_s, "check=strict"},
+ {Opt_check_n, "check=normal"},
+ {Opt_check_r, "check=r"},
+ {Opt_check_s, "check=s"},
+ {Opt_check_n, "check=n"},
+ {Opt_uid, "uid=%u"},
+ {Opt_gid, "gid=%u"},
+ {Opt_umask, "umask=%o"},
+ {Opt_dmask, "dmask=%o"},
+ {Opt_fmask, "fmask=%o"},
+ {Opt_codepage, "codepage=%u"},
+ {Opt_nocase, "nocase"},
+ {Opt_quiet, "quiet"},
+ {Opt_showexec, "showexec"},
+ {Opt_debug, "debug"},
+ {Opt_immutable, "sys_immutable"},
+ {Opt_obsolate, "conv=binary"},
+ {Opt_obsolate, "conv=text"},
+ {Opt_obsolate, "conv=auto"},
+ {Opt_obsolate, "conv=b"},
+ {Opt_obsolate, "conv=t"},
+ {Opt_obsolate, "conv=a"},
+ {Opt_obsolate, "fat=%u"},
+ {Opt_obsolate, "blocksize=%u"},
+ {Opt_obsolate, "cvf_format=%20s"},
+ {Opt_obsolate, "cvf_options=%100s"},
+ {Opt_obsolate, "posix"},
+ {Opt_err, NULL}
+};
+static match_table_t msdos_tokens = {
+ {Opt_nodots, "nodots"},
+ {Opt_nodots, "dotsOK=no"},
+ {Opt_dots, "dots"},
+ {Opt_dots, "dotsOK=yes"},
+ {Opt_err, NULL}
+};
+static match_table_t vfat_tokens = {
+ {Opt_charset, "iocharset=%s"},
+ {Opt_shortname_lower, "shortname=lower"},
+ {Opt_shortname_win95, "shortname=win95"},
+ {Opt_shortname_winnt, "shortname=winnt"},
+ {Opt_shortname_mixed, "shortname=mixed"},
+ {Opt_utf8_no, "utf8=0"}, /* 0 or no or false */
+ {Opt_utf8_no, "utf8=no"},
+ {Opt_utf8_no, "utf8=false"},
+ {Opt_utf8_yes, "utf8=1"}, /* empty or 1 or yes or true */
+ {Opt_utf8_yes, "utf8=yes"},
+ {Opt_utf8_yes, "utf8=true"},
+ {Opt_utf8_yes, "utf8"},
+ {Opt_uni_xl_no, "uni_xlate=0"}, /* 0 or no or false */
+ {Opt_uni_xl_no, "uni_xlate=no"},
+ {Opt_uni_xl_no, "uni_xlate=false"},
+ {Opt_uni_xl_yes, "uni_xlate=1"}, /* empty or 1 or yes or true */
+ {Opt_uni_xl_yes, "uni_xlate=yes"},
+ {Opt_uni_xl_yes, "uni_xlate=true"},
+ {Opt_uni_xl_yes, "uni_xlate"},
+ {Opt_nonumtail_no, "nonumtail=0"}, /* 0 or no or false */
+ {Opt_nonumtail_no, "nonumtail=no"},
+ {Opt_nonumtail_no, "nonumtail=false"},
+ {Opt_nonumtail_yes, "nonumtail=1"}, /* empty or 1 or yes or true */
+ {Opt_nonumtail_yes, "nonumtail=yes"},
+ {Opt_nonumtail_yes, "nonumtail=true"},
+ {Opt_nonumtail_yes, "nonumtail"},
+ {Opt_err, NULL}
+};
+
+static int parse_options(char *options, int is_vfat, int *debug,
+ struct fat_mount_options *opts)
+{
+ char *p;
+ substring_t args[MAX_OPT_ARGS];
+ int option;
+ char *iocharset;
+
+ opts->isvfat = is_vfat;
+
+ opts->fs_uid = current->uid;
+ opts->fs_gid = current->gid;
+ opts->fs_fmask = opts->fs_dmask = current->fs->umask;
+ opts->codepage = fat_default_codepage;
+ opts->iocharset = fat_default_iocharset;
+ if (is_vfat)
+ opts->shortname = VFAT_SFN_DISPLAY_LOWER|VFAT_SFN_CREATE_WIN95;
+ else
+ opts->shortname = 0;
+ opts->name_check = 'n';
+ opts->quiet = opts->showexec = opts->sys_immutable = opts->dotsOK = 0;
+ opts->utf8 = opts->unicode_xlate = 0;
+ opts->numtail = 1;
+ opts->nocase = 0;
+ *debug = 0;
+
+ if (!options)
+ return 0;
+
+ while ((p = strsep(&options, ",")) != NULL) {
+ int token;
+ if (!*p)
+ continue;
+
+ token = match_token(p, fat_tokens, args);
+ if (token == Opt_err) {
+ if (is_vfat)
+ token = match_token(p, vfat_tokens, args);
+ else
+ token = match_token(p, msdos_tokens, args);
+ }
+ switch (token) {
+ case Opt_check_s:
+ opts->name_check = 's';
+ break;
+ case Opt_check_r:
+ opts->name_check = 'r';
+ break;
+ case Opt_check_n:
+ opts->name_check = 'n';
+ break;
+ case Opt_nocase:
+ if (!is_vfat)
+ opts->nocase = 1;
+ else {
+ /* for backward compatibility */
+ opts->shortname = VFAT_SFN_DISPLAY_WIN95
+ | VFAT_SFN_CREATE_WIN95;
+ }
+ break;
+ case Opt_quiet:
+ opts->quiet = 1;
+ break;
+ case Opt_showexec:
+ opts->showexec = 1;
+ break;
+ case Opt_debug:
+ *debug = 1;
+ break;
+ case Opt_immutable:
+ opts->sys_immutable = 1;
+ break;
+ case Opt_uid:
+ if (match_int(&args[0], &option))
+ return 0;
+ opts->fs_uid = option;
+ break;
+ case Opt_gid:
+ if (match_int(&args[0], &option))
+ return 0;
+ opts->fs_gid = option;
+ break;
+ case Opt_umask:
+ if (match_octal(&args[0], &option))
+ return 0;
+ opts->fs_fmask = opts->fs_dmask = option;
+ break;
+ case Opt_dmask:
+ if (match_octal(&args[0], &option))
+ return 0;
+ opts->fs_dmask = option;
+ break;
+ case Opt_fmask:
+ if (match_octal(&args[0], &option))
+ return 0;
+ opts->fs_fmask = option;
+ break;
+ case Opt_codepage:
+ if (match_int(&args[0], &option))
+ return 0;
+ opts->codepage = option;
+ break;
+
+ /* msdos specific */
+ case Opt_dots:
+ opts->dotsOK = 1;
+ break;
+ case Opt_nodots:
+ opts->dotsOK = 0;
+ break;
+
+ /* vfat specific */
+ case Opt_charset:
+ if (opts->iocharset != fat_default_iocharset)
+ kfree(opts->iocharset);
+ iocharset = match_strdup(&args[0]);
+ if (!iocharset)
+ return -ENOMEM;
+ opts->iocharset = iocharset;
+ break;
+ case Opt_shortname_lower:
+ opts->shortname = VFAT_SFN_DISPLAY_LOWER
+ | VFAT_SFN_CREATE_WIN95;
+ break;
+ case Opt_shortname_win95:
+ opts->shortname = VFAT_SFN_DISPLAY_WIN95
+ | VFAT_SFN_CREATE_WIN95;
+ break;
+ case Opt_shortname_winnt:
+ opts->shortname = VFAT_SFN_DISPLAY_WINNT
+ | VFAT_SFN_CREATE_WINNT;
+ break;
+ case Opt_shortname_mixed:
+ opts->shortname = VFAT_SFN_DISPLAY_WINNT
+ | VFAT_SFN_CREATE_WIN95;
+ break;
+ case Opt_utf8_no: /* 0 or no or false */
+ opts->utf8 = 0;
+ break;
+ case Opt_utf8_yes: /* empty or 1 or yes or true */
+ opts->utf8 = 1;
+ break;
+ case Opt_uni_xl_no: /* 0 or no or false */
+ opts->unicode_xlate = 0;
+ break;
+ case Opt_uni_xl_yes: /* empty or 1 or yes or true */
+ opts->unicode_xlate = 1;
+ break;
+ case Opt_nonumtail_no: /* 0 or no or false */
+ opts->numtail = 1; /* negated option */
+ break;
+ case Opt_nonumtail_yes: /* empty or 1 or yes or true */
+ opts->numtail = 0; /* negated option */
+ break;
+
+ /* obsolete mount options */
+ case Opt_obsolate:
+ printk(KERN_INFO "FAT: \"%s\" option is obsolete, "
+ "not supported now\n", p);
+ break;
+ /* unknown option */
+ default:
+ printk(KERN_ERR "FAT: Unrecognized mount option \"%s\" "
+ "or missing value\n", p);
+ return -EINVAL;
+ }
+ }
+ /* UTF8 doesn't provide FAT semantics */
+ if (!strcmp(opts->iocharset, "utf8")) {
+ printk(KERN_ERR "FAT: utf8 is not a recommended IO charset"
+ " for FAT filesystems, filesystem will be case sensitive!\n");
+ }
+
+ if (opts->unicode_xlate)
+ opts->utf8 = 0;
+
+ return 0;
+}
+
+static int fat_read_root(struct inode *inode)
+{
+ struct super_block *sb = inode->i_sb;
+ struct msdos_sb_info *sbi = MSDOS_SB(sb);
+ int error;
+
+ MSDOS_I(inode)->i_pos = 0;
+ inode->i_uid = sbi->options.fs_uid;
+ inode->i_gid = sbi->options.fs_gid;
+ inode->i_version++;
+ inode->i_generation = 0;
+ inode->i_mode = (S_IRWXUGO & ~sbi->options.fs_dmask) | S_IFDIR;
+ inode->i_op = sbi->dir_ops;
+ inode->i_fop = &fat_dir_operations;
+ if (sbi->fat_bits == 32) {
+ MSDOS_I(inode)->i_start = sbi->root_cluster;
+ error = fat_calc_dir_size(inode);
+ if (error < 0)
+ return error;
+ } else {
+ MSDOS_I(inode)->i_start = 0;
+ inode->i_size = sbi->dir_entries * sizeof(struct msdos_dir_entry);
+ }
+ inode->i_blksize = sbi->cluster_size;
+ inode->i_blocks = ((inode->i_size + (sbi->cluster_size - 1))
+ & ~((loff_t)sbi->cluster_size - 1)) >> 9;
+ MSDOS_I(inode)->i_logstart = 0;
+ MSDOS_I(inode)->mmu_private = inode->i_size;
+
+ MSDOS_I(inode)->i_attrs = ATTR_NONE;
+ inode->i_mtime.tv_sec = inode->i_atime.tv_sec = inode->i_ctime.tv_sec = 0;
+ inode->i_mtime.tv_nsec = inode->i_atime.tv_nsec = inode->i_ctime.tv_nsec = 0;
+ inode->i_nlink = fat_subdirs(inode)+2;
+
+ return 0;
+}
+
+/*
+ * Read the super block of an MS-DOS FS.
+ */
+int fat_fill_super(struct super_block *sb, void *data, int silent,
+ struct inode_operations *fs_dir_inode_ops, int isvfat)
+{
+ struct inode *root_inode = NULL;
+ struct buffer_head *bh;
+ struct fat_boot_sector *b;
+ struct msdos_sb_info *sbi;
+ u16 logical_sector_size;
+ u32 total_sectors, total_clusters, fat_clusters, rootdir_sectors;
+ int debug;
+ unsigned int media;
+ long error;
+ char buf[50];
+
+ sbi = kmalloc(sizeof(struct msdos_sb_info), GFP_KERNEL);
+ if (!sbi)
+ return -ENOMEM;
+ sb->s_fs_info = sbi;
+ memset(sbi, 0, sizeof(struct msdos_sb_info));
+
+ sb->s_flags |= MS_NODIRATIME;
+ sb->s_magic = MSDOS_SUPER_MAGIC;
+ sb->s_op = &fat_sops;
+ sb->s_export_op = &fat_export_ops;
+ sbi->dir_ops = fs_dir_inode_ops;
+
+ error = parse_options(data, isvfat, &debug, &sbi->options);
+ if (error)
+ goto out_fail;
+
+ error = -EIO;
+ sb_min_blocksize(sb, 512);
+ bh = sb_bread(sb, 0);
+ if (bh == NULL) {
+ printk(KERN_ERR "FAT: unable to read boot sector\n");
+ goto out_fail;
+ }
+
+ b = (struct fat_boot_sector *) bh->b_data;
+ if (!b->reserved) {
+ if (!silent)
+ printk(KERN_ERR "FAT: bogus number of reserved sectors\n");
+ brelse(bh);
+ goto out_invalid;
+ }
+ if (!b->fats) {
+ if (!silent)
+ printk(KERN_ERR "FAT: bogus number of FAT structure\n");
+ brelse(bh);
+ goto out_invalid;
+ }
+
+ /*
+ * Earlier we checked here that b->secs_track and b->head are nonzero,
+ * but it turns out valid FAT filesystems can have zero there.
+ */
+
+ media = b->media;
+ if (!FAT_VALID_MEDIA(media)) {
+ if (!silent)
+ printk(KERN_ERR "FAT: invalid media value (0x%02x)\n",
+ media);
+ brelse(bh);
+ goto out_invalid;
+ }
+ logical_sector_size =
+ le16_to_cpu(get_unaligned((__le16 *)&b->sector_size));
+ if (!logical_sector_size
+ || (logical_sector_size & (logical_sector_size - 1))
+ || (logical_sector_size < 512)
+ || (PAGE_CACHE_SIZE < logical_sector_size)) {
+ if (!silent)
+ printk(KERN_ERR "FAT: bogus logical sector size %u\n",
+ logical_sector_size);
+ brelse(bh);
+ goto out_invalid;
+ }
+ sbi->sec_per_clus = b->sec_per_clus;
+ if (!sbi->sec_per_clus
+ || (sbi->sec_per_clus & (sbi->sec_per_clus - 1))) {
+ if (!silent)
+ printk(KERN_ERR "FAT: bogus sectors per cluster %u\n",
+ sbi->sec_per_clus);
+ brelse(bh);
+ goto out_invalid;
+ }
+
+ if (logical_sector_size < sb->s_blocksize) {
+ printk(KERN_ERR "FAT: logical sector size too small for device"
+ " (logical sector size = %u)\n", logical_sector_size);
+ brelse(bh);
+ goto out_fail;
+ }
+ if (logical_sector_size > sb->s_blocksize) {
+ brelse(bh);
+
+ if (!sb_set_blocksize(sb, logical_sector_size)) {
+ printk(KERN_ERR "FAT: unable to set blocksize %u\n",
+ logical_sector_size);
+ goto out_fail;
+ }
+ bh = sb_bread(sb, 0);
+ if (bh == NULL) {
+ printk(KERN_ERR "FAT: unable to read boot sector"
+ " (logical sector size = %lu)\n",
+ sb->s_blocksize);
+ goto out_fail;
+ }
+ b = (struct fat_boot_sector *) bh->b_data;
+ }
+
+ sbi->cluster_size = sb->s_blocksize * sbi->sec_per_clus;
+ sbi->cluster_bits = ffs(sbi->cluster_size) - 1;
+ sbi->fats = b->fats;
+ sbi->fat_bits = 0; /* Don't know yet */
+ sbi->fat_start = le16_to_cpu(b->reserved);
+ sbi->fat_length = le16_to_cpu(b->fat_length);
+ sbi->root_cluster = 0;
+ sbi->free_clusters = -1; /* Don't know yet */
+ sbi->prev_free = FAT_START_ENT;
+
+ if (!sbi->fat_length && b->fat32_length) {
+ struct fat_boot_fsinfo *fsinfo;
+ struct buffer_head *fsinfo_bh;
+
+ /* Must be FAT32 */
+ sbi->fat_bits = 32;
+ sbi->fat_length = le32_to_cpu(b->fat32_length);
+ sbi->root_cluster = le32_to_cpu(b->root_cluster);
+
+ sb->s_maxbytes = 0xffffffff;
+
+ /* MC - if info_sector is 0, don't multiply by 0 */
+ sbi->fsinfo_sector = le16_to_cpu(b->info_sector);
+ if (sbi->fsinfo_sector == 0)
+ sbi->fsinfo_sector = 1;
+
+ fsinfo_bh = sb_bread(sb, sbi->fsinfo_sector);
+ if (fsinfo_bh == NULL) {
+ printk(KERN_ERR "FAT: bread failed, FSINFO block"
+ " (sector = %lu)\n", sbi->fsinfo_sector);
+ brelse(bh);
+ goto out_fail;
+ }
+
+ fsinfo = (struct fat_boot_fsinfo *)fsinfo_bh->b_data;
+ if (!IS_FSINFO(fsinfo)) {
+ printk(KERN_WARNING
+ "FAT: Did not find valid FSINFO signature.\n"
+ " Found signature1 0x%08x signature2 0x%08x"
+ " (sector = %lu)\n",
+ le32_to_cpu(fsinfo->signature1),
+ le32_to_cpu(fsinfo->signature2),
+ sbi->fsinfo_sector);
+ } else {
+ sbi->free_clusters = le32_to_cpu(fsinfo->free_clusters);
+ sbi->prev_free = le32_to_cpu(fsinfo->next_cluster);
+ }
+
+ brelse(fsinfo_bh);
+ }
+
+ sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry);
+ sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1;
+
+ sbi->dir_start = sbi->fat_start + sbi->fats * sbi->fat_length;
+ sbi->dir_entries =
+ le16_to_cpu(get_unaligned((__le16 *)&b->dir_entries));
+ if (sbi->dir_entries & (sbi->dir_per_block - 1)) {
+ if (!silent)
+ printk(KERN_ERR "FAT: bogus directroy-entries per block"
+ " (%u)\n", sbi->dir_entries);
+ brelse(bh);
+ goto out_invalid;
+ }
+
+ rootdir_sectors = sbi->dir_entries
+ * sizeof(struct msdos_dir_entry) / sb->s_blocksize;
+ sbi->data_start = sbi->dir_start + rootdir_sectors;
+ total_sectors = le16_to_cpu(get_unaligned((__le16 *)&b->sectors));
+ if (total_sectors == 0)
+ total_sectors = le32_to_cpu(b->total_sect);
+
+ total_clusters = (total_sectors - sbi->data_start) / sbi->sec_per_clus;
+
+ if (sbi->fat_bits != 32)
+ sbi->fat_bits = (total_clusters > MAX_FAT12) ? 16 : 12;
+
+ /* check that FAT table does not overflow */
+ fat_clusters = sbi->fat_length * sb->s_blocksize * 8 / sbi->fat_bits;
+ total_clusters = min(total_clusters, fat_clusters - FAT_START_ENT);
+ if (total_clusters > MAX_FAT(sb)) {
+ if (!silent)
+ printk(KERN_ERR "FAT: count of clusters too big (%u)\n",
+ total_clusters);
+ brelse(bh);
+ goto out_invalid;
+ }
+
+ sbi->max_cluster = total_clusters + FAT_START_ENT;
+ /* check the free_clusters, it's not necessarily correct */
+ if (sbi->free_clusters != -1 && sbi->free_clusters > total_clusters)
+ sbi->free_clusters = -1;
+ /* check the prev_free, it's not necessarily correct */
+ sbi->prev_free %= sbi->max_cluster;
+ if (sbi->prev_free < FAT_START_ENT)
+ sbi->prev_free = FAT_START_ENT;
+
+ brelse(bh);
+
+ /* set up enough so that it can read an inode */
+ fat_hash_init(sb);
+ fat_ent_access_init(sb);
+
+ /*
+ * The low byte of FAT's first entry must have same value with
+ * media-field. But in real world, too many devices is
+ * writing wrong value. So, removed that validity check.
+ *
+ * if (FAT_FIRST_ENT(sb, media) != first)
+ */
+
+ error = -EINVAL;
+ sprintf(buf, "cp%d", sbi->options.codepage);
+ sbi->nls_disk = load_nls(buf);
+ if (!sbi->nls_disk) {
+ printk(KERN_ERR "FAT: codepage %s not found\n", buf);
+ goto out_fail;
+ }
+
+ /* FIXME: utf8 is using iocharset for upper/lower conversion */
+ if (sbi->options.isvfat) {
+ sbi->nls_io = load_nls(sbi->options.iocharset);
+ if (!sbi->nls_io) {
+ printk(KERN_ERR "FAT: IO charset %s not found\n",
+ sbi->options.iocharset);
+ goto out_fail;
+ }
+ }
+
+ error = -ENOMEM;
+ root_inode = new_inode(sb);
+ if (!root_inode)
+ goto out_fail;
+ root_inode->i_ino = MSDOS_ROOT_INO;
+ root_inode->i_version = 1;
+ error = fat_read_root(root_inode);
+ if (error < 0)
+ goto out_fail;
+ error = -ENOMEM;
+ insert_inode_hash(root_inode);
+ sb->s_root = d_alloc_root(root_inode);
+ if (!sb->s_root) {
+ printk(KERN_ERR "FAT: get root inode failed\n");
+ goto out_fail;
+ }
+
+ return 0;
+
+out_invalid:
+ error = -EINVAL;
+ if (!silent)
+ printk(KERN_INFO "VFS: Can't find a valid FAT filesystem"
+ " on dev %s.\n", sb->s_id);
+
+out_fail:
+ if (root_inode)
+ iput(root_inode);
+ if (sbi->nls_io)
+ unload_nls(sbi->nls_io);
+ if (sbi->nls_disk)
+ unload_nls(sbi->nls_disk);
+ if (sbi->options.iocharset != fat_default_iocharset)
+ kfree(sbi->options.iocharset);
+ sb->s_fs_info = NULL;
+ kfree(sbi);
+ return error;
+}
+
+EXPORT_SYMBOL(fat_fill_super);
+
+int __init fat_cache_init(void);
+void __exit fat_cache_destroy(void);
+
+static int __init init_fat_fs(void)
+{
+ int ret;
+
+ ret = fat_cache_init();
+ if (ret < 0)
+ return ret;
+ return fat_init_inodecache();
+}
+
+static void __exit exit_fat_fs(void)
+{
+ fat_cache_destroy();
+ fat_destroy_inodecache();
+}
+
+module_init(init_fat_fs)
+module_exit(exit_fat_fs)
+
+MODULE_LICENSE("GPL");