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!

7 files changed, 4098 insertions, 0 deletions

diff --git a/fs/fat/Makefile b/fs/fat/Makefile
new file mode 100644
index 00000000000..bfb5f06cf2c
--- /dev/null
+++ b/fs/fat/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the Linux fat filesystem support.
+#
+
+obj-$(CONFIG_FAT_FS) += fat.o
+
+fat-objs := cache.o dir.o fatent.o file.o inode.o misc.o
diff --git a/fs/fat/cache.c b/fs/fat/cache.c
new file mode 100644
index 00000000000..7c52e465a61
--- /dev/null
+++ b/fs/fat/cache.c
@@ -0,0 +1,324 @@
+/*
+ *  linux/fs/fat/cache.c
+ *
+ *  Written 1992,1993 by Werner Almesberger
+ *
+ *  Mar 1999. AV. Changed cache, so that it uses the starting cluster instead
+ *	of inode number.
+ *  May 1999. AV. Fixed the bogosity with FAT32 (read "FAT28"). Fscking lusers.
+ */
+
+#include <linux/fs.h>
+#include <linux/msdos_fs.h>
+#include <linux/buffer_head.h>
+
+/* this must be > 0. */
+#define FAT_MAX_CACHE	8
+
+struct fat_cache {
+	struct list_head cache_list;
+	int nr_contig;	/* number of contiguous clusters */
+	int fcluster;	/* cluster number in the file. */
+	int dcluster;	/* cluster number on disk. */
+};
+
+struct fat_cache_id {
+	unsigned int id;
+	int nr_contig;
+	int fcluster;
+	int dcluster;
+};
+
+static inline int fat_max_cache(struct inode *inode)
+{
+	return FAT_MAX_CACHE;
+}
+
+static kmem_cache_t *fat_cache_cachep;
+
+static void init_once(void *foo, kmem_cache_t *cachep, unsigned long flags)
+{
+	struct fat_cache *cache = (struct fat_cache *)foo;
+
+	if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
+	    SLAB_CTOR_CONSTRUCTOR)
+		INIT_LIST_HEAD(&cache->cache_list);
+}
+
+int __init fat_cache_init(void)
+{
+	fat_cache_cachep = kmem_cache_create("fat_cache",
+				sizeof(struct fat_cache),
+				0, SLAB_RECLAIM_ACCOUNT,
+				init_once, NULL);
+	if (fat_cache_cachep == NULL)
+		return -ENOMEM;
+	return 0;
+}
+
+void __exit fat_cache_destroy(void)
+{
+	if (kmem_cache_destroy(fat_cache_cachep))
+		printk(KERN_INFO "fat_cache: not all structures were freed\n");
+}
+
+static inline struct fat_cache *fat_cache_alloc(struct inode *inode)
+{
+	return kmem_cache_alloc(fat_cache_cachep, SLAB_KERNEL);
+}
+
+static inline void fat_cache_free(struct fat_cache *cache)
+{
+	BUG_ON(!list_empty(&cache->cache_list));
+	kmem_cache_free(fat_cache_cachep, cache);
+}
+
+static inline void fat_cache_update_lru(struct inode *inode,
+					struct fat_cache *cache)
+{
+	if (MSDOS_I(inode)->cache_lru.next != &cache->cache_list)
+		list_move(&cache->cache_list, &MSDOS_I(inode)->cache_lru);
+}
+
+static int fat_cache_lookup(struct inode *inode, int fclus,
+			    struct fat_cache_id *cid,
+			    int *cached_fclus, int *cached_dclus)
+{
+	static struct fat_cache nohit = { .fcluster = 0, };
+
+	struct fat_cache *hit = &nohit, *p;
+	int offset = -1;
+
+	spin_lock(&MSDOS_I(inode)->cache_lru_lock);
+	list_for_each_entry(p, &MSDOS_I(inode)->cache_lru, cache_list) {
+		/* Find the cache of "fclus" or nearest cache. */
+		if (p->fcluster <= fclus && hit->fcluster < p->fcluster) {
+			hit = p;
+			if ((hit->fcluster + hit->nr_contig) < fclus) {
+				offset = hit->nr_contig;
+			} else {
+				offset = fclus - hit->fcluster;
+				break;
+			}
+		}
+	}
+	if (hit != &nohit) {
+		fat_cache_update_lru(inode, hit);
+
+		cid->id = MSDOS_I(inode)->cache_valid_id;
+		cid->nr_contig = hit->nr_contig;
+		cid->fcluster = hit->fcluster;
+		cid->dcluster = hit->dcluster;
+		*cached_fclus = cid->fcluster + offset;
+		*cached_dclus = cid->dcluster + offset;
+	}
+	spin_unlock(&MSDOS_I(inode)->cache_lru_lock);
+
+	return offset;
+}
+
+static struct fat_cache *fat_cache_merge(struct inode *inode,
+					 struct fat_cache_id *new)
+{
+	struct fat_cache *p;
+
+	list_for_each_entry(p, &MSDOS_I(inode)->cache_lru, cache_list) {
+		/* Find the same part as "new" in cluster-chain. */
+		if (p->fcluster == new->fcluster) {
+			BUG_ON(p->dcluster != new->dcluster);
+			if (new->nr_contig > p->nr_contig)
+				p->nr_contig = new->nr_contig;
+			return p;
+		}
+	}
+	return NULL;
+}
+
+static void fat_cache_add(struct inode *inode, struct fat_cache_id *new)
+{
+	struct fat_cache *cache, *tmp;
+
+	if (new->fcluster == -1) /* dummy cache */
+		return;
+
+	spin_lock(&MSDOS_I(inode)->cache_lru_lock);
+	if (new->id != FAT_CACHE_VALID &&
+	    new->id != MSDOS_I(inode)->cache_valid_id)
+		goto out;	/* this cache was invalidated */
+
+	cache = fat_cache_merge(inode, new);
+	if (cache == NULL) {
+		if (MSDOS_I(inode)->nr_caches < fat_max_cache(inode)) {
+			MSDOS_I(inode)->nr_caches++;
+			spin_unlock(&MSDOS_I(inode)->cache_lru_lock);
+
+			tmp = fat_cache_alloc(inode);
+			spin_lock(&MSDOS_I(inode)->cache_lru_lock);
+			cache = fat_cache_merge(inode, new);
+			if (cache != NULL) {
+				MSDOS_I(inode)->nr_caches--;
+				fat_cache_free(tmp);
+				goto out_update_lru;
+			}
+			cache = tmp;
+		} else {
+			struct list_head *p = MSDOS_I(inode)->cache_lru.prev;
+			cache = list_entry(p, struct fat_cache, cache_list);
+		}
+		cache->fcluster = new->fcluster;
+		cache->dcluster = new->dcluster;
+		cache->nr_contig = new->nr_contig;
+	}
+out_update_lru:
+	fat_cache_update_lru(inode, cache);
+out:
+	spin_unlock(&MSDOS_I(inode)->cache_lru_lock);
+}
+
+/*
+ * Cache invalidation occurs rarely, thus the LRU chain is not updated. It
+ * fixes itself after a while.
+ */
+static void __fat_cache_inval_inode(struct inode *inode)
+{
+	struct msdos_inode_info *i = MSDOS_I(inode);
+	struct fat_cache *cache;
+
+	while (!list_empty(&i->cache_lru)) {
+		cache = list_entry(i->cache_lru.next, struct fat_cache, cache_list);
+		list_del_init(&cache->cache_list);
+		i->nr_caches--;
+		fat_cache_free(cache);
+	}
+	/* Update. The copy of caches before this id is discarded. */
+	i->cache_valid_id++;
+	if (i->cache_valid_id == FAT_CACHE_VALID)
+		i->cache_valid_id++;
+}
+
+void fat_cache_inval_inode(struct inode *inode)
+{
+	spin_lock(&MSDOS_I(inode)->cache_lru_lock);
+	__fat_cache_inval_inode(inode);
+	spin_unlock(&MSDOS_I(inode)->cache_lru_lock);
+}
+
+static inline int cache_contiguous(struct fat_cache_id *cid, int dclus)
+{
+	cid->nr_contig++;
+	return ((cid->dcluster + cid->nr_contig) == dclus);
+}
+
+static inline void cache_init(struct fat_cache_id *cid, int fclus, int dclus)
+{
+	cid->id = FAT_CACHE_VALID;
+	cid->fcluster = fclus;
+	cid->dcluster = dclus;
+	cid->nr_contig = 0;
+}
+
+int fat_get_cluster(struct inode *inode, int cluster, int *fclus, int *dclus)
+{
+	struct super_block *sb = inode->i_sb;
+	const int limit = sb->s_maxbytes >> MSDOS_SB(sb)->cluster_bits;
+	struct fat_entry fatent;
+	struct fat_cache_id cid;
+	int nr;
+
+	BUG_ON(MSDOS_I(inode)->i_start == 0);
+
+	*fclus = 0;
+	*dclus = MSDOS_I(inode)->i_start;
+	if (cluster == 0)
+		return 0;
+
+	if (fat_cache_lookup(inode, cluster, &cid, fclus, dclus) < 0) {
+		/*
+		 * dummy, always not contiguous
+		 * This is reinitialized by cache_init(), later.
+		 */
+		cache_init(&cid, -1, -1);
+	}
+
+	fatent_init(&fatent);
+	while (*fclus < cluster) {
+		/* prevent the infinite loop of cluster chain */
+		if (*fclus > limit) {
+			fat_fs_panic(sb, "%s: detected the cluster chain loop"
+				     " (i_pos %lld)", __FUNCTION__,
+				     MSDOS_I(inode)->i_pos);
+			nr = -EIO;
+			goto out;
+		}
+
+		nr = fat_ent_read(inode, &fatent, *dclus);
+		if (nr < 0)
+			goto out;
+		else if (nr == FAT_ENT_FREE) {
+			fat_fs_panic(sb, "%s: invalid cluster chain"
+				     " (i_pos %lld)", __FUNCTION__,
+				     MSDOS_I(inode)->i_pos);
+			nr = -EIO;
+			goto out;
+		} else if (nr == FAT_ENT_EOF) {
+			fat_cache_add(inode, &cid);
+			goto out;
+		}
+		(*fclus)++;
+		*dclus = nr;
+		if (!cache_contiguous(&cid, *dclus))
+			cache_init(&cid, *fclus, *dclus);
+	}
+	nr = 0;
+	fat_cache_add(inode, &cid);
+out:
+	fatent_brelse(&fatent);
+	return nr;
+}
+
+static int fat_bmap_cluster(struct inode *inode, int cluster)
+{
+	struct super_block *sb = inode->i_sb;
+	int ret, fclus, dclus;
+
+	if (MSDOS_I(inode)->i_start == 0)
+		return 0;
+
+	ret = fat_get_cluster(inode, cluster, &fclus, &dclus);
+	if (ret < 0)
+		return ret;
+	else if (ret == FAT_ENT_EOF) {
+		fat_fs_panic(sb, "%s: request beyond EOF (i_pos %lld)",
+			     __FUNCTION__, MSDOS_I(inode)->i_pos);
+		return -EIO;
+	}
+	return dclus;
+}
+
+int fat_bmap(struct inode *inode, sector_t sector, sector_t *phys)
+{
+	struct super_block *sb = inode->i_sb;
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	sector_t last_block;
+	int cluster, offset;
+
+	*phys = 0;
+	if ((sbi->fat_bits != 32) && (inode->i_ino == MSDOS_ROOT_INO)) {
+		if (sector < (sbi->dir_entries >> sbi->dir_per_block_bits))
+			*phys = sector + sbi->dir_start;
+		return 0;
+	}
+	last_block = (MSDOS_I(inode)->mmu_private + (sb->s_blocksize - 1))
+		>> sb->s_blocksize_bits;
+	if (sector >= last_block)
+		return 0;
+
+	cluster = sector >> (sbi->cluster_bits - sb->s_blocksize_bits);
+	offset  = sector & (sbi->sec_per_clus - 1);
+	cluster = fat_bmap_cluster(inode, cluster);
+	if (cluster < 0)
+		return cluster;
+	else if (cluster)
+		*phys = fat_clus_to_blknr(sbi, cluster) + offset;
+	return 0;
+}
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
new file mode 100644
index 00000000000..e5ae1b720dd
--- /dev/null
+++ b/fs/fat/dir.c
@@ -0,0 +1,1271 @@
+/*
+ *  linux/fs/fat/dir.c
+ *
+ *  directory handling functions for fat-based filesystems
+ *
+ *  Written 1992,1993 by Werner Almesberger
+ *
+ *  Hidden files 1995 by Albert Cahalan <albert@ccs.neu.edu> <adc@coe.neu.edu>
+ *
+ *  VFAT extensions by Gordon Chaffee <chaffee@plateau.cs.berkeley.edu>
+ *  Merged with msdos fs by Henrik Storner <storner@osiris.ping.dk>
+ *  Rewritten for constant inumbers. Plugged buffer overrun in readdir(). AV
+ *  Short name translation 1999, 2001 by Wolfram Pienkoss <wp@bszh.de>
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/time.h>
+#include <linux/msdos_fs.h>
+#include <linux/dirent.h>
+#include <linux/smp_lock.h>
+#include <linux/buffer_head.h>
+#include <asm/uaccess.h>
+
+static inline loff_t fat_make_i_pos(struct super_block *sb,
+				    struct buffer_head *bh,
+				    struct msdos_dir_entry *de)
+{
+	return ((loff_t)bh->b_blocknr << MSDOS_SB(sb)->dir_per_block_bits)
+		| (de - (struct msdos_dir_entry *)bh->b_data);
+}
+
+/* Returns the inode number of the directory entry at offset pos. If bh is
+   non-NULL, it is brelse'd before. Pos is incremented. The buffer header is
+   returned in bh.
+   AV. Most often we do it item-by-item. Makes sense to optimize.
+   AV. OK, there we go: if both bh and de are non-NULL we assume that we just
+   AV. want the next entry (took one explicit de=NULL in vfat/namei.c).
+   AV. It's done in fat_get_entry() (inlined), here the slow case lives.
+   AV. Additionally, when we return -1 (i.e. reached the end of directory)
+   AV. we make bh NULL.
+ */
+static int fat__get_entry(struct inode *dir, loff_t *pos,
+			  struct buffer_head **bh, struct msdos_dir_entry **de)
+{
+	struct super_block *sb = dir->i_sb;
+	sector_t phys, iblock;
+	int offset;
+	int err;
+
+next:
+	if (*bh)
+		brelse(*bh);
+
+	*bh = NULL;
+	iblock = *pos >> sb->s_blocksize_bits;
+	err = fat_bmap(dir, iblock, &phys);
+	if (err || !phys)
+		return -1;	/* beyond EOF or error */
+
+	*bh = sb_bread(sb, phys);
+	if (*bh == NULL) {
+		printk(KERN_ERR "FAT: Directory bread(block %llu) failed\n",
+		       (unsigned long long)phys);
+		/* skip this block */
+		*pos = (iblock + 1) << sb->s_blocksize_bits;
+		goto next;
+	}
+
+	offset = *pos & (sb->s_blocksize - 1);
+	*pos += sizeof(struct msdos_dir_entry);
+	*de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
+
+	return 0;
+}
+
+static inline int fat_get_entry(struct inode *dir, loff_t *pos,
+				struct buffer_head **bh,
+				struct msdos_dir_entry **de)
+{
+	/* Fast stuff first */
+	if (*bh && *de &&
+	    (*de - (struct msdos_dir_entry *)(*bh)->b_data) < MSDOS_SB(dir->i_sb)->dir_per_block - 1) {
+		*pos += sizeof(struct msdos_dir_entry);
+		(*de)++;
+		return 0;
+	}
+	return fat__get_entry(dir, pos, bh, de);
+}
+
+/*
+ * Convert Unicode 16 to UTF8, translated Unicode, or ASCII.
+ * If uni_xlate is enabled and we can't get a 1:1 conversion, use a
+ * colon as an escape character since it is normally invalid on the vfat
+ * filesystem. The following four characters are the hexadecimal digits
+ * of Unicode value. This lets us do a full dump and restore of Unicode
+ * filenames. We could get into some trouble with long Unicode names,
+ * but ignore that right now.
+ * Ahem... Stack smashing in ring 0 isn't fun. Fixed.
+ */
+static int uni16_to_x8(unsigned char *ascii, wchar_t *uni, int uni_xlate,
+		       struct nls_table *nls)
+{
+	wchar_t *ip, ec;
+	unsigned char *op, nc;
+	int charlen;
+	int k;
+
+	ip = uni;
+	op = ascii;
+
+	while (*ip) {
+		ec = *ip++;
+		if ( (charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE)) > 0) {
+			op += charlen;
+		} else {
+			if (uni_xlate == 1) {
+				*op = ':';
+				for (k = 4; k > 0; k--) {
+					nc = ec & 0xF;
+					op[k] = nc > 9	? nc + ('a' - 10)
+							: nc + '0';
+					ec >>= 4;
+				}
+				op += 5;
+			} else {
+				*op++ = '?';
+			}
+		}
+		/* We have some slack there, so it's OK */
+		if (op>ascii+256) {
+			op = ascii + 256;
+			break;
+		}
+	}
+	*op = 0;
+	return (op - ascii);
+}
+
+static inline int
+fat_short2uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
+{
+	int charlen;
+
+	charlen = t->char2uni(c, clen, uni);
+	if (charlen < 0) {
+		*uni = 0x003f;	/* a question mark */
+		charlen = 1;
+	}
+	return charlen;
+}
+
+static inline int
+fat_short2lower_uni(struct nls_table *t, unsigned char *c, int clen, wchar_t *uni)
+{
+	int charlen;
+	wchar_t wc;
+
+	charlen = t->char2uni(c, clen, &wc);
+	if (charlen < 0) {
+		*uni = 0x003f;	/* a question mark */
+		charlen = 1;
+	} else if (charlen <= 1) {
+		unsigned char nc = t->charset2lower[*c];
+
+		if (!nc)
+			nc = *c;
+
+		if ( (charlen = t->char2uni(&nc, 1, uni)) < 0) {
+			*uni = 0x003f;	/* a question mark */
+			charlen = 1;
+		}
+	} else
+		*uni = wc;
+
+	return charlen;
+}
+
+static inline int
+fat_shortname2uni(struct nls_table *nls, unsigned char *buf, int buf_size,
+		  wchar_t *uni_buf, unsigned short opt, int lower)
+{
+	int len = 0;
+
+	if (opt & VFAT_SFN_DISPLAY_LOWER)
+		len =  fat_short2lower_uni(nls, buf, buf_size, uni_buf);
+	else if (opt & VFAT_SFN_DISPLAY_WIN95)
+		len = fat_short2uni(nls, buf, buf_size, uni_buf);
+	else if (opt & VFAT_SFN_DISPLAY_WINNT) {
+		if (lower)
+			len = fat_short2lower_uni(nls, buf, buf_size, uni_buf);
+		else
+			len = fat_short2uni(nls, buf, buf_size, uni_buf);
+	} else
+		len = fat_short2uni(nls, buf, buf_size, uni_buf);
+
+	return len;
+}
+
+/*
+ * Return values: negative -> error, 0 -> not found, positive -> found,
+ * value is the total amount of slots, including the shortname entry.
+ */
+int fat_search_long(struct inode *inode, const unsigned char *name,
+		    int name_len, struct fat_slot_info *sinfo)
+{
+	struct super_block *sb = inode->i_sb;
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	struct buffer_head *bh = NULL;
+	struct msdos_dir_entry *de;
+	struct nls_table *nls_io = sbi->nls_io;
+	struct nls_table *nls_disk = sbi->nls_disk;
+	wchar_t bufuname[14];
+	unsigned char xlate_len, nr_slots;
+	wchar_t *unicode = NULL;
+	unsigned char work[8], bufname[260];	/* 256 + 4 */
+	int uni_xlate = sbi->options.unicode_xlate;
+	int utf8 = sbi->options.utf8;
+	int anycase = (sbi->options.name_check != 's');
+	unsigned short opt_shortname = sbi->options.shortname;
+	loff_t cpos = 0;
+	int chl, i, j, last_u, err;
+
+	err = -ENOENT;
+	while(1) {
+		if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
+			goto EODir;
+parse_record:
+		nr_slots = 0;
+		if (de->name[0] == DELETED_FLAG)
+			continue;
+		if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
+			continue;
+		if (de->attr != ATTR_EXT && IS_FREE(de->name))
+			continue;
+		if (de->attr == ATTR_EXT) {
+			struct msdos_dir_slot *ds;
+			unsigned char id;
+			unsigned char slot;
+			unsigned char slots;
+			unsigned char sum;
+			unsigned char alias_checksum;
+
+			if (!unicode) {
+				unicode = (wchar_t *)
+					__get_free_page(GFP_KERNEL);
+				if (!unicode) {
+					brelse(bh);
+					return -ENOMEM;
+				}
+			}
+parse_long:
+			slots = 0;
+			ds = (struct msdos_dir_slot *) de;
+			id = ds->id;
+			if (!(id & 0x40))
+				continue;
+			slots = id & ~0x40;
+			if (slots > 20 || !slots)	/* ceil(256 * 2 / 26) */
+				continue;
+			nr_slots = slots;
+			alias_checksum = ds->alias_checksum;
+
+			slot = slots;
+			while (1) {
+				int offset;
+
+				slot--;
+				offset = slot * 13;
+				fat16_towchar(unicode + offset, ds->name0_4, 5);
+				fat16_towchar(unicode + offset + 5, ds->name5_10, 6);
+				fat16_towchar(unicode + offset + 11, ds->name11_12, 2);
+
+				if (ds->id & 0x40) {
+					unicode[offset + 13] = 0;
+				}
+				if (fat_get_entry(inode, &cpos, &bh, &de) < 0)
+					goto EODir;
+				if (slot == 0)
+					break;
+				ds = (struct msdos_dir_slot *) de;
+				if (ds->attr !=  ATTR_EXT)
+					goto parse_record;
+				if ((ds->id & ~0x40) != slot)
+					goto parse_long;
+				if (ds->alias_checksum != alias_checksum)
+					goto parse_long;
+			}
+			if (de->name[0] == DELETED_FLAG)
+				continue;
+			if (de->attr ==  ATTR_EXT)
+				goto parse_long;
+			if (IS_FREE(de->name) || (de->attr & ATTR_VOLUME))
+				continue;
+			for (sum = 0, i = 0; i < 11; i++)
+				sum = (((sum&1)<<7)|((sum&0xfe)>>1)) + de->name[i];
+			if (sum != alias_checksum)
+				nr_slots = 0;
+		}
+
+		memcpy(work, de->name, sizeof(de->name));
+		/* see namei.c, msdos_format_name */
+		if (work[0] == 0x05)
+			work[0] = 0xE5;
+		for (i = 0, j = 0, last_u = 0; i < 8;) {
+			if (!work[i]) break;
+			chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
+						&bufuname[j++], opt_shortname,
+						de->lcase & CASE_LOWER_BASE);
+			if (chl <= 1) {
+				if (work[i] != ' ')
+					last_u = j;
+			} else {
+				last_u = j;
+			}
+			i += chl;
+		}
+		j = last_u;
+		fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
+		for (i = 0; i < 3;) {
+			if (!de->ext[i]) break;
+			chl = fat_shortname2uni(nls_disk, &de->ext[i], 3 - i,
+						&bufuname[j++], opt_shortname,
+						de->lcase & CASE_LOWER_EXT);
+			if (chl <= 1) {
+				if (de->ext[i] != ' ')
+					last_u = j;
+			} else {
+				last_u = j;
+			}
+			i += chl;
+		}
+		if (!last_u)
+			continue;
+
+		bufuname[last_u] = 0x0000;
+		xlate_len = utf8
+			?utf8_wcstombs(bufname, bufuname, sizeof(bufname))
+			:uni16_to_x8(bufname, bufuname, uni_xlate, nls_io);
+		if (xlate_len == name_len)
+			if ((!anycase && !memcmp(name, bufname, xlate_len)) ||
+			    (anycase && !nls_strnicmp(nls_io, name, bufname,
+								xlate_len)))
+				goto Found;
+
+		if (nr_slots) {
+			xlate_len = utf8
+				?utf8_wcstombs(bufname, unicode, sizeof(bufname))
+				:uni16_to_x8(bufname, unicode, uni_xlate, nls_io);
+			if (xlate_len != name_len)
+				continue;
+			if ((!anycase && !memcmp(name, bufname, xlate_len)) ||
+			    (anycase && !nls_strnicmp(nls_io, name, bufname,
+								xlate_len)))
+				goto Found;
+		}
+	}
+
+Found:
+	nr_slots++;	/* include the de */
+	sinfo->slot_off = cpos - nr_slots * sizeof(*de);
+	sinfo->nr_slots = nr_slots;
+	sinfo->de = de;
+	sinfo->bh = bh;
+	sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
+	err = 0;
+EODir:
+	if (unicode)
+		free_page((unsigned long)unicode);
+
+	return err;
+}
+
+EXPORT_SYMBOL(fat_search_long);
+
+struct fat_ioctl_filldir_callback {
+	struct dirent __user *dirent;
+	int result;
+	/* for dir ioctl */
+	const char *longname;
+	int long_len;
+	const char *shortname;
+	int short_len;
+};
+
+static int fat_readdirx(struct inode *inode, struct file *filp, void *dirent,
+			filldir_t filldir, int short_only, int both)
+{
+	struct super_block *sb = inode->i_sb;
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	struct buffer_head *bh;
+	struct msdos_dir_entry *de;
+	struct nls_table *nls_io = sbi->nls_io;
+	struct nls_table *nls_disk = sbi->nls_disk;
+	unsigned char long_slots;
+	const char *fill_name;
+	int fill_len;
+	wchar_t bufuname[14];
+	wchar_t *unicode = NULL;
+	unsigned char c, work[8], bufname[56], *ptname = bufname;
+	unsigned long lpos, dummy, *furrfu = &lpos;
+	int uni_xlate = sbi->options.unicode_xlate;
+	int isvfat = sbi->options.isvfat;
+	int utf8 = sbi->options.utf8;
+	int nocase = sbi->options.nocase;
+	unsigned short opt_shortname = sbi->options.shortname;
+	unsigned long inum;
+	int chi, chl, i, i2, j, last, last_u, dotoffset = 0;
+	loff_t cpos;
+	int ret = 0;
+
+	lock_kernel();
+
+	cpos = filp->f_pos;
+	/* Fake . and .. for the root directory. */
+	if (inode->i_ino == MSDOS_ROOT_INO) {
+		while (cpos < 2) {
+			if (filldir(dirent, "..", cpos+1, cpos, MSDOS_ROOT_INO, DT_DIR) < 0)
+				goto out;
+			cpos++;
+			filp->f_pos++;
+		}
+		if (cpos == 2) {
+			dummy = 2;
+			furrfu = &dummy;
+			cpos = 0;
+		}
+	}
+	if (cpos & (sizeof(struct msdos_dir_entry)-1)) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	bh = NULL;
+GetNew:
+	long_slots = 0;
+	if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
+		goto EODir;
+	/* Check for long filename entry */
+	if (isvfat) {
+		if (de->name[0] == DELETED_FLAG)
+			goto RecEnd;
+		if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
+			goto RecEnd;
+		if (de->attr != ATTR_EXT && IS_FREE(de->name))
+			goto RecEnd;
+	} else {
+		if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name))
+			goto RecEnd;
+	}
+
+	if (isvfat && de->attr == ATTR_EXT) {
+		struct msdos_dir_slot *ds;
+		unsigned char id;
+		unsigned char slot;
+		unsigned char slots;
+		unsigned char sum;
+		unsigned char alias_checksum;
+
+		if (!unicode) {
+			unicode = (wchar_t *)__get_free_page(GFP_KERNEL);
+			if (!unicode) {
+				filp->f_pos = cpos;
+				brelse(bh);
+				ret = -ENOMEM;
+				goto out;
+			}
+		}
+ParseLong:
+		slots = 0;
+		ds = (struct msdos_dir_slot *) de;
+		id = ds->id;
+		if (!(id & 0x40))
+			goto RecEnd;
+		slots = id & ~0x40;
+		if (slots > 20 || !slots)	/* ceil(256 * 2 / 26) */
+			goto RecEnd;
+		long_slots = slots;
+		alias_checksum = ds->alias_checksum;
+
+		slot = slots;
+		while (1) {
+			int offset;
+
+			slot--;
+			offset = slot * 13;
+			fat16_towchar(unicode + offset, ds->name0_4, 5);
+			fat16_towchar(unicode + offset + 5, ds->name5_10, 6);
+			fat16_towchar(unicode + offset + 11, ds->name11_12, 2);
+
+			if (ds->id & 0x40) {
+				unicode[offset + 13] = 0;
+			}
+			if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
+				goto EODir;
+			if (slot == 0)
+				break;
+			ds = (struct msdos_dir_slot *) de;
+			if (ds->attr !=  ATTR_EXT)
+				goto RecEnd;	/* XXX */
+			if ((ds->id & ~0x40) != slot)
+				goto ParseLong;
+			if (ds->alias_checksum != alias_checksum)
+				goto ParseLong;
+		}
+		if (de->name[0] == DELETED_FLAG)
+			goto RecEnd;
+		if (de->attr ==  ATTR_EXT)
+			goto ParseLong;
+		if (IS_FREE(de->name) || (de->attr & ATTR_VOLUME))
+			goto RecEnd;
+		for (sum = 0, i = 0; i < 11; i++)
+			sum = (((sum&1)<<7)|((sum&0xfe)>>1)) + de->name[i];
+		if (sum != alias_checksum)
+			long_slots = 0;
+	}
+
+	if (sbi->options.dotsOK) {
+		ptname = bufname;
+		dotoffset = 0;
+		if (de->attr & ATTR_HIDDEN) {
+			*ptname++ = '.';
+			dotoffset = 1;
+		}
+	}
+
+	memcpy(work, de->name, sizeof(de->name));
+	/* see namei.c, msdos_format_name */
+	if (work[0] == 0x05)
+		work[0] = 0xE5;
+	for (i = 0, j = 0, last = 0, last_u = 0; i < 8;) {
+		if (!(c = work[i])) break;
+		chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
+					&bufuname[j++], opt_shortname,
+					de->lcase & CASE_LOWER_BASE);
+		if (chl <= 1) {
+			ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
+			if (c != ' ') {
+				last = i;
+				last_u = j;
+			}
+		} else {
+			last_u = j;
+			for (chi = 0; chi < chl && i < 8; chi++) {
+				ptname[i] = work[i];
+				i++; last = i;
+			}
+		}
+	}
+	i = last;
+	j = last_u;
+	fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);
+	ptname[i++] = '.';
+	for (i2 = 0; i2 < 3;) {
+		if (!(c = de->ext[i2])) break;
+		chl = fat_shortname2uni(nls_disk, &de->ext[i2], 3 - i2,
+					&bufuname[j++], opt_shortname,
+					de->lcase & CASE_LOWER_EXT);
+		if (chl <= 1) {
+			i2++;
+			ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;
+			if (c != ' ') {
+				last = i;
+				last_u = j;
+			}
+		} else {
+			last_u = j;
+			for (chi = 0; chi < chl && i2 < 3; chi++) {
+				ptname[i++] = de->ext[i2++];
+				last = i;
+			}
+		}
+	}
+	if (!last)
+		goto RecEnd;
+
+	i = last + dotoffset;
+	j = last_u;
+
+	lpos = cpos - (long_slots+1)*sizeof(struct msdos_dir_entry);
+	if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME))
+		inum = inode->i_ino;
+	else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
+		inum = parent_ino(filp->f_dentry);
+	} else {
+		loff_t i_pos = fat_make_i_pos(sb, bh, de);
+		struct inode *tmp = fat_iget(sb, i_pos);
+		if (tmp) {
+			inum = tmp->i_ino;
+			iput(tmp);
+		} else
+			inum = iunique(sb, MSDOS_ROOT_INO);
+	}
+
+	if (isvfat) {
+		bufuname[j] = 0x0000;
+		i = utf8 ? utf8_wcstombs(bufname, bufuname, sizeof(bufname))
+			 : uni16_to_x8(bufname, bufuname, uni_xlate, nls_io);
+	}
+
+	fill_name = bufname;
+	fill_len = i;
+	if (!short_only && long_slots) {
+		/* convert the unicode long name. 261 is maximum size
+		 * of unicode buffer. (13 * slots + nul) */
+		void *longname = unicode + 261;
+		int buf_size = PAGE_SIZE - (261 * sizeof(unicode[0]));
+		int long_len = utf8
+			? utf8_wcstombs(longname, unicode, buf_size)
+			: uni16_to_x8(longname, unicode, uni_xlate, nls_io);
+
+		if (!both) {
+			fill_name = longname;
+			fill_len = long_len;
+		} else {
+			/* hack for fat_ioctl_filldir() */
+			struct fat_ioctl_filldir_callback *p = dirent;
+
+			p->longname = longname;
+			p->long_len = long_len;
+			p->shortname = bufname;
+			p->short_len = i;
+			fill_name = NULL;
+			fill_len = 0;
+		}
+	}
+	if (filldir(dirent, fill_name, fill_len, *furrfu, inum,
+		    (de->attr & ATTR_DIR) ? DT_DIR : DT_REG) < 0)
+		goto FillFailed;
+
+RecEnd:
+	furrfu = &lpos;
+	filp->f_pos = cpos;
+	goto GetNew;
+EODir:
+	filp->f_pos = cpos;
+FillFailed:
+	if (bh)
+		brelse(bh);
+	if (unicode)
+		free_page((unsigned long)unicode);
+out:
+	unlock_kernel();
+	return ret;
+}
+
+static int fat_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+	struct inode *inode = filp->f_dentry->d_inode;
+	return fat_readdirx(inode, filp, dirent, filldir, 0, 0);
+}
+
+static int fat_ioctl_filldir(void *__buf, const char *name, int name_len,
+			     loff_t offset, ino_t ino, unsigned int d_type)
+{
+	struct fat_ioctl_filldir_callback *buf = __buf;
+	struct dirent __user *d1 = buf->dirent;
+	struct dirent __user *d2 = d1 + 1;
+
+	if (buf->result)
+		return -EINVAL;
+	buf->result++;
+
+	if (name != NULL) {
+		/* dirent has only short name */
+		if (name_len >= sizeof(d1->d_name))
+			name_len = sizeof(d1->d_name) - 1;
+
+		if (put_user(0, d2->d_name)			||
+		    put_user(0, &d2->d_reclen)			||
+		    copy_to_user(d1->d_name, name, name_len)	||
+		    put_user(0, d1->d_name + name_len)		||
+		    put_user(name_len, &d1->d_reclen))
+			goto efault;
+	} else {
+		/* dirent has short and long name */
+		const char *longname = buf->longname;
+		int long_len = buf->long_len;
+		const char *shortname = buf->shortname;
+		int short_len = buf->short_len;
+
+		if (long_len >= sizeof(d1->d_name))
+			long_len = sizeof(d1->d_name) - 1;
+		if (short_len >= sizeof(d1->d_name))
+			short_len = sizeof(d1->d_name) - 1;
+
+		if (copy_to_user(d2->d_name, longname, long_len)	||
+		    put_user(0, d2->d_name + long_len)			||
+		    put_user(long_len, &d2->d_reclen)			||
+		    put_user(ino, &d2->d_ino)				||
+		    put_user(offset, &d2->d_off)			||
+		    copy_to_user(d1->d_name, shortname, short_len)	||
+		    put_user(0, d1->d_name + short_len)			||
+		    put_user(short_len, &d1->d_reclen))
+			goto efault;
+	}
+	return 0;
+efault:
+	buf->result = -EFAULT;
+	return -EFAULT;
+}
+
+static int fat_dir_ioctl(struct inode * inode, struct file * filp,
+		  unsigned int cmd, unsigned long arg)
+{
+	struct fat_ioctl_filldir_callback buf;
+	struct dirent __user *d1;
+	int ret, short_only, both;
+
+	switch (cmd) {
+	case VFAT_IOCTL_READDIR_SHORT:
+		short_only = 1;
+		both = 0;
+		break;
+	case VFAT_IOCTL_READDIR_BOTH:
+		short_only = 0;
+		both = 1;
+		break;
+	default:
+		return fat_generic_ioctl(inode, filp, cmd, arg);
+	}
+
+	d1 = (struct dirent __user *)arg;
+	if (!access_ok(VERIFY_WRITE, d1, sizeof(struct dirent[2])))
+		return -EFAULT;
+	/*
+	 * Yes, we don't need this put_user() absolutely. However old
+	 * code didn't return the right value. So, app use this value,
+	 * in order to check whether it is EOF.
+	 */
+	if (put_user(0, &d1->d_reclen))
+		return -EFAULT;
+
+	buf.dirent = d1;
+	buf.result = 0;
+	down(&inode->i_sem);
+	ret = -ENOENT;
+	if (!IS_DEADDIR(inode)) {
+		ret = fat_readdirx(inode, filp, &buf, fat_ioctl_filldir,
+				   short_only, both);
+	}
+	up(&inode->i_sem);
+	if (ret >= 0)
+		ret = buf.result;
+	return ret;
+}
+
+struct file_operations fat_dir_operations = {
+	.read		= generic_read_dir,
+	.readdir	= fat_readdir,
+	.ioctl		= fat_dir_ioctl,
+	.fsync		= file_fsync,
+};
+
+static int fat_get_short_entry(struct inode *dir, loff_t *pos,
+			       struct buffer_head **bh,
+			       struct msdos_dir_entry **de)
+{
+	while (fat_get_entry(dir, pos, bh, de) >= 0) {
+		/* free entry or long name entry or volume label */
+		if (!IS_FREE((*de)->name) && !((*de)->attr & ATTR_VOLUME))
+			return 0;
+	}
+	return -ENOENT;
+}
+
+/*
+ * The ".." entry can not provide the "struct fat_slot_info" informations
+ * for inode. So, this function provide the some informations only.
+ */
+int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
+			 struct msdos_dir_entry **de, loff_t *i_pos)
+{
+	loff_t offset;
+
+	offset = 0;
+	*bh = NULL;
+	while (fat_get_short_entry(dir, &offset, bh, de) >= 0) {
+		if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME)) {
+			*i_pos = fat_make_i_pos(dir->i_sb, *bh, *de);
+			return 0;
+		}
+	}
+	return -ENOENT;
+}
+
+EXPORT_SYMBOL(fat_get_dotdot_entry);
+
+/* See if directory is empty */
+int fat_dir_empty(struct inode *dir)
+{