Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1414 insertions, 0 deletions

diff --git a/fs/fat/dir.c b/fs/fat/dir.c
new file mode 100644
index 000000000..00235b8a1
--- /dev/null
+++ b/fs/fat/dir.c
@@ -0,0 +1,1414 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  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/slab.h>
+#include <linux/compat.h>
+#include <linux/uaccess.h>
+#include <linux/iversion.h>
+#include "fat.h"
+
+/*
+ * Maximum buffer size of short name.
+ * [(MSDOS_NAME + '.') * max one char + nul]
+ * For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul]
+ */
+#define FAT_MAX_SHORT_SIZE	((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1)
+/*
+ * Maximum buffer size of unicode chars from slots.
+ * [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)]
+ */
+#define FAT_MAX_UNI_CHARS	((MSDOS_SLOTS - 1) * 13 + 1)
+#define FAT_MAX_UNI_SIZE	(FAT_MAX_UNI_CHARS * sizeof(wchar_t))
+
+static inline unsigned char fat_tolower(unsigned char c)
+{
+	return ((c >= 'A') && (c <= 'Z')) ? c+32 : c;
+}
+
+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);
+}
+
+static inline void fat_dir_readahead(struct inode *dir, sector_t iblock,
+				     sector_t phys)
+{
+	struct super_block *sb = dir->i_sb;
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	struct buffer_head *bh;
+	int sec;
+
+	/* This is not a first sector of cluster, or sec_per_clus == 1 */
+	if ((iblock & (sbi->sec_per_clus - 1)) || sbi->sec_per_clus == 1)
+		return;
+	/* root dir of FAT12/FAT16 */
+	if (!is_fat32(sbi) && (dir->i_ino == MSDOS_ROOT_INO))
+		return;
+
+	bh = sb_find_get_block(sb, phys);
+	if (bh == NULL || !buffer_uptodate(bh)) {
+		for (sec = 0; sec < sbi->sec_per_clus; sec++)
+			sb_breadahead(sb, phys + sec);
+	}
+	brelse(bh);
+}
+
+/* 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;
+	unsigned long mapped_blocks;
+	int err, offset;
+
+next:
+	brelse(*bh);
+	*bh = NULL;
+	iblock = *pos >> sb->s_blocksize_bits;
+	err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0, false);
+	if (err || !phys)
+		return -1;	/* beyond EOF or error */
+
+	fat_dir_readahead(dir, iblock, phys);
+
+	*bh = sb_bread(sb, phys);
+	if (*bh == NULL) {
+		fat_msg_ratelimit(sb, KERN_ERR,
+			"Directory bread(block %llu) failed", (llu)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 UTF-8, 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(struct super_block *sb, unsigned char *ascii,
+		       const wchar_t *uni, int len, struct nls_table *nls)
+{
+	int uni_xlate = MSDOS_SB(sb)->options.unicode_xlate;
+	const wchar_t *ip;
+	wchar_t ec;
+	unsigned char *op;
+	int charlen;
+
+	ip = uni;
+	op = ascii;
+
+	while (*ip && ((len - NLS_MAX_CHARSET_SIZE) > 0)) {
+		ec = *ip++;
+		charlen = nls->uni2char(ec, op, NLS_MAX_CHARSET_SIZE);
+		if (charlen > 0) {
+			op += charlen;
+			len -= charlen;
+		} else {
+			if (uni_xlate == 1) {
+				*op++ = ':';
+				op = hex_byte_pack(op, ec >> 8);
+				op = hex_byte_pack(op, ec);
+				len -= 5;
+			} else {
+				*op++ = '?';
+				len--;
+			}
+		}
+	}
+
+	if (unlikely(*ip)) {
+		fat_msg(sb, KERN_WARNING,
+			"filename was truncated while converting.");
+	}
+
+	*op = 0;
+	return op - ascii;
+}
+
+static inline int fat_uni_to_x8(struct super_block *sb, const wchar_t *uni,
+				unsigned char *buf, int size)
+{
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	if (sbi->options.utf8)
+		return utf16s_to_utf8s(uni, FAT_MAX_UNI_CHARS,
+				UTF16_HOST_ENDIAN, buf, size);
+	else
+		return uni16_to_x8(sb, buf, uni, size, sbi->nls_io);
+}
+
+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;
+
+		charlen = t->char2uni(&nc, 1, uni);
+		if (charlen < 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;
+}
+
+static inline int fat_name_match(struct msdos_sb_info *sbi,
+				 const unsigned char *a, int a_len,
+				 const unsigned char *b, int b_len)
+{
+	if (a_len != b_len)
+		return 0;
+
+	if (sbi->options.name_check != 's')
+		return !nls_strnicmp(sbi->nls_io, a, b, a_len);
+	else
+		return !memcmp(a, b, a_len);
+}
+
+enum { PARSE_INVALID = 1, PARSE_NOT_LONGNAME, PARSE_EOF, };
+
+/**
+ * fat_parse_long - Parse extended directory entry.
+ *
+ * This function returns zero on success, negative value on error, or one of
+ * the following:
+ *
+ * %PARSE_INVALID - Directory entry is invalid.
+ * %PARSE_NOT_LONGNAME - Directory entry does not contain longname.
+ * %PARSE_EOF - Directory has no more entries.
+ */
+static int fat_parse_long(struct inode *dir, loff_t *pos,
+			  struct buffer_head **bh, struct msdos_dir_entry **de,
+			  wchar_t **unicode, unsigned char *nr_slots)
+{
+	struct msdos_dir_slot *ds;
+	unsigned char id, slot, slots, alias_checksum;
+
+	if (!*unicode) {
+		*unicode = __getname();
+		if (!*unicode) {
+			brelse(*bh);
+			return -ENOMEM;
+		}
+	}
+parse_long:
+	ds = (struct msdos_dir_slot *)*de;
+	id = ds->id;
+	if (!(id & 0x40))
+		return PARSE_INVALID;
+	slots = id & ~0x40;
+	if (slots > 20 || !slots)	/* ceil(256 * 2 / 26) */
+		return PARSE_INVALID;
+	*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(dir, pos, bh, de) < 0)
+			return PARSE_EOF;
+		if (slot == 0)
+			break;
+		ds = (struct msdos_dir_slot *)*de;
+		if (ds->attr != ATTR_EXT)
+			return PARSE_NOT_LONGNAME;
+		if ((ds->id & ~0x40) != slot)
+			goto parse_long;
+		if (ds->alias_checksum != alias_checksum)
+			goto parse_long;
+	}
+	if ((*de)->name[0] == DELETED_FLAG)
+		return PARSE_INVALID;
+	if ((*de)->attr == ATTR_EXT)
+		goto parse_long;
+	if (IS_FREE((*de)->name) || ((*de)->attr & ATTR_VOLUME))
+		return PARSE_INVALID;
+	if (fat_checksum((*de)->name) != alias_checksum)
+		*nr_slots = 0;
+
+	return 0;
+}
+
+/**
+ * fat_parse_short - Parse MS-DOS (short) directory entry.
+ * @sb:		superblock
+ * @de:		directory entry to parse
+ * @name:	FAT_MAX_SHORT_SIZE array in which to place extracted name
+ * @dot_hidden:	Nonzero == prepend '.' to names with ATTR_HIDDEN
+ *
+ * Returns the number of characters extracted into 'name'.
+ */
+static int fat_parse_short(struct super_block *sb,
+			   const struct msdos_dir_entry *de,
+			   unsigned char *name, int dot_hidden)
+{
+	const struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	int isvfat = sbi->options.isvfat;
+	int nocase = sbi->options.nocase;
+	unsigned short opt_shortname = sbi->options.shortname;
+	struct nls_table *nls_disk = sbi->nls_disk;
+	wchar_t uni_name[14];
+	unsigned char c, work[MSDOS_NAME];
+	unsigned char *ptname = name;
+	int chi, chl, i, j, k;
+	int dotoffset = 0;
+	int name_len = 0, uni_len = 0;
+
+	if (!isvfat && dot_hidden && (de->attr & ATTR_HIDDEN)) {
+		*ptname++ = '.';
+		dotoffset = 1;
+	}
+
+	memcpy(work, de->name, sizeof(work));
+	/* For an explanation of the special treatment of 0x05 in
+	 * filenames, see msdos_format_name in namei_msdos.c
+	 */
+	if (work[0] == 0x05)
+		work[0] = 0xE5;
+
+	/* Filename */
+	for (i = 0, j = 0; i < 8;) {
+		c = work[i];
+		if (!c)
+			break;
+		chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,
+					&uni_name[j++], opt_shortname,
+					de->lcase & CASE_LOWER_BASE);
+		if (chl <= 1) {
+			if (!isvfat)
+				ptname[i] = nocase ? c : fat_tolower(c);
+			i++;
+			if (c != ' ') {
+				name_len = i;
+				uni_len  = j;
+			}
+		} else {
+			uni_len = j;
+			if (isvfat)
+				i += min(chl, 8-i);
+			else {
+				for (chi = 0; chi < chl && i < 8; chi++, i++)
+					ptname[i] = work[i];
+			}
+			if (chl)
+				name_len = i;
+		}
+	}
+
+	i = name_len;
+	j = uni_len;
+	fat_short2uni(nls_disk, ".", 1, &uni_name[j++]);
+	if (!isvfat)
+		ptname[i] = '.';
+	i++;
+
+	/* Extension */
+	for (k = 8; k < MSDOS_NAME;) {
+		c = work[k];
+		if (!c)
+			break;
+		chl = fat_shortname2uni(nls_disk, &work[k], MSDOS_NAME - k,
+					&uni_name[j++], opt_shortname,
+					de->lcase & CASE_LOWER_EXT);
+		if (chl <= 1) {
+			k++;
+			if (!isvfat)
+				ptname[i] = nocase ? c : fat_tolower(c);
+			i++;
+			if (c != ' ') {
+				name_len = i;
+				uni_len  = j;
+			}
+		} else {
+			uni_len = j;
+			if (isvfat) {
+				int offset = min(chl, MSDOS_NAME-k);
+				k += offset;
+				i += offset;
+			} else {
+				for (chi = 0; chi < chl && k < MSDOS_NAME;
+				     chi++, i++, k++) {
+						ptname[i] = work[k];
+				}
+			}
+			if (chl)
+				name_len = i;
+		}
+	}
+
+	if (name_len > 0) {
+		name_len += dotoffset;
+
+		if (sbi->options.isvfat) {
+			uni_name[uni_len] = 0x0000;
+			name_len = fat_uni_to_x8(sb, uni_name, name,
+						 FAT_MAX_SHORT_SIZE);
+		}
+	}
+
+	return name_len;
+}
+
+/*
+ * Return values: negative -> error/not found, 0 -> found.
+ */
+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;
+	unsigned char nr_slots;
+	wchar_t *unicode = NULL;
+	unsigned char bufname[FAT_MAX_SHORT_SIZE];
+	loff_t cpos = 0;
+	int err, len;
+
+	err = -ENOENT;
+	while (1) {
+		if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
+			goto end_of_dir;
+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) {
+			int status = fat_parse_long(inode, &cpos, &bh, &de,
+						    &unicode, &nr_slots);
+			if (status < 0) {
+				err = status;
+				goto end_of_dir;
+			} else if (status == PARSE_INVALID)
+				continue;
+			else if (status == PARSE_NOT_LONGNAME)
+				goto parse_record;
+			else if (status == PARSE_EOF)
+				goto end_of_dir;
+		}
+
+		/* Never prepend '.' to hidden files here.
+		 * That is done only for msdos mounts (and only when
+		 * 'dotsOK=yes'); if we are executing here, it is in the
+		 * context of a vfat mount.
+		 */
+		len = fat_parse_short(sb, de, bufname, 0);
+		if (len == 0)
+			continue;
+
+		/* Compare shortname */
+		if (fat_name_match(sbi, name, name_len, bufname, len))
+			goto found;
+
+		if (nr_slots) {
+			void *longname = unicode + FAT_MAX_UNI_CHARS;
+			int size = PATH_MAX - FAT_MAX_UNI_SIZE;
+
+			/* Compare longname */
+			len = fat_uni_to_x8(sb, unicode, longname, size);
+			if (fat_name_match(sbi, name, name_len, longname, 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;
+end_of_dir:
+	if (unicode)
+		__putname(unicode);
+
+	return err;
+}
+EXPORT_SYMBOL_GPL(fat_search_long);
+
+struct fat_ioctl_filldir_callback {
+	struct dir_context ctx;
+	void __user *dirent;
+	int result;
+	/* for dir ioctl */
+	const char *longname;
+	int long_len;
+	const char *shortname;
+	int short_len;
+};
+
+static int __fat_readdir(struct inode *inode, struct file *file,
+			 struct dir_context *ctx, int short_only,
+			 struct fat_ioctl_filldir_callback *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;
+	unsigned char nr_slots;
+	wchar_t *unicode = NULL;
+	unsigned char bufname[FAT_MAX_SHORT_SIZE];
+	int isvfat = sbi->options.isvfat;
+	const char *fill_name = NULL;
+	int fake_offset = 0;
+	loff_t cpos;
+	int short_len = 0, fill_len = 0;
+	int ret = 0;
+
+	mutex_lock(&sbi->s_lock);
+
+	cpos = ctx->pos;
+	/* Fake . and .. for the root directory. */
+	if (inode->i_ino == MSDOS_ROOT_INO) {
+		if (!dir_emit_dots(file, ctx))
+			goto out;
+		if (ctx->pos == 2) {
+			fake_offset = 1;
+			cpos = 0;
+		}
+	}
+	if (cpos & (sizeof(struct msdos_dir_entry) - 1)) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	bh = NULL;
+get_new:
+	if (fat_get_entry(inode, &cpos, &bh, &de) == -1)
+		goto end_of_dir;
+parse_record:
+	nr_slots = 0;
+	/*
+	 * Check for long filename entry, but if short_only, we don't
+	 * need to parse long filename.
+	 */
+	if (isvfat && !short_only) {
+		if (de->name[0] == DELETED_FLAG)
+			goto record_end;
+		if (de->attr != ATTR_EXT && (de->attr & ATTR_VOLUME))
+			goto record_end;
+		if (de->attr != ATTR_EXT && IS_FREE(de->name))
+			goto record_end;
+	} else {
+		if ((de->attr & ATTR_VOLUME) || IS_FREE(de->name))
+			goto record_end;
+	}
+
+	if (isvfat && de->attr == ATTR_EXT) {
+		int status = fat_parse_long(inode, &cpos, &bh, &de,
+					    &unicode, &nr_slots);
+		if (status < 0) {
+			bh = NULL;
+			ret = status;
+			goto end_of_dir;
+		} else if (status == PARSE_INVALID)
+			goto record_end;
+		else if (status == PARSE_NOT_LONGNAME)
+			goto parse_record;
+		else if (status == PARSE_EOF)
+			goto end_of_dir;
+
+		if (nr_slots) {
+			void *longname = unicode + FAT_MAX_UNI_CHARS;
+			int size = PATH_MAX - FAT_MAX_UNI_SIZE;
+			int len = fat_uni_to_x8(sb, unicode, longname, size);
+
+			fill_name = longname;
+			fill_len = len;
+			/* !both && !short_only, so we don't need shortname. */
+			if (!both)
+				goto start_filldir;
+
+			short_len = fat_parse_short(sb, de, bufname,
+						    sbi->options.dotsOK);
+			if (short_len == 0)
+				goto record_end;
+			/* hack for fat_ioctl_filldir() */
+			both->longname = fill_name;
+			both->long_len = fill_len;
+			both->shortname = bufname;
+			both->short_len = short_len;
+			fill_name = NULL;
+			fill_len = 0;
+			goto start_filldir;
+		}
+	}
+
+	short_len = fat_parse_short(sb, de, bufname, sbi->options.dotsOK);
+	if (short_len == 0)
+		goto record_end;
+
+	fill_name = bufname;
+	fill_len = short_len;
+
+start_filldir:
+	ctx->pos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry);
+	if (fake_offset && ctx->pos < 2)
+		ctx->pos = 2;
+
+	if (!memcmp(de->name, MSDOS_DOT, MSDOS_NAME)) {
+		if (!dir_emit_dot(file, ctx))
+			goto fill_failed;
+	} else if (!memcmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
+		if (!dir_emit_dotdot(file, ctx))
+			goto fill_failed;
+	} else {
+		unsigned long inum;
+		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 (!dir_emit(ctx, fill_name, fill_len, inum,
+			    (de->attr & ATTR_DIR) ? DT_DIR : DT_REG))
+			goto fill_failed;
+	}
+
+record_end:
+	fake_offset = 0;
+	ctx->pos = cpos;
+	goto get_new;
+
+end_of_dir:
+	if (fake_offset && cpos < 2)
+		ctx->pos = 2;
+	else
+		ctx->pos = cpos;
+fill_failed:
+	brelse(bh);
+	if (unicode)
+		__putname(unicode);
+out:
+	mutex_unlock(&sbi->s_lock);
+
+	return ret;
+}
+
+static int fat_readdir(struct file *file, struct dir_context *ctx)
+{
+	return __fat_readdir(file_inode(file), file, ctx, 0, NULL);
+}
+
+#define FAT_IOCTL_FILLDIR_FUNC(func, dirent_type)			   \
+static bool func(struct dir_context *ctx, const char *name, int name_len,  \
+			     loff_t offset, u64 ino, unsigned int d_type)  \
+{									   \
+	struct fat_ioctl_filldir_callback *buf =			   \
+		container_of(ctx, struct fat_ioctl_filldir_callback, ctx); \
+	struct dirent_type __user *d1 = buf->dirent;			   \
+	struct dirent_type __user *d2 = d1 + 1;				   \
+									   \
+	if (buf->result)						   \
+		return false;						   \
+	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[0])			||	   \
+		    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 true;							   \
+efault:									   \
+	buf->result = -EFAULT;						   \
+	return false;							   \
+}
+
+FAT_IOCTL_FILLDIR_FUNC(fat_ioctl_filldir, __fat_dirent)
+
+static int fat_ioctl_readdir(struct inode *inode, struct file *file,
+			     void __user *dirent, filldir_t filldir,
+			     int short_only, int both)
+{
+	struct fat_ioctl_filldir_callback buf = {
+		.ctx.actor = filldir,
+		.dirent = dirent
+	};
+	int ret;
+
+	buf.dirent = dirent;
+	buf.result = 0;
+	inode_lock_shared(inode);
+	buf.ctx.pos = file->f_pos;
+	ret = -ENOENT;
+	if (!IS_DEADDIR(inode)) {
+		ret = __fat_readdir(inode, file, &buf.ctx,
+				    short_only, both ? &buf : NULL);
+		file->f_pos = buf.ctx.pos;
+	}
+	inode_unlock_shared(inode);
+	if (ret >= 0)
+		ret = buf.result;
+	return ret;
+}
+
+static long fat_dir_ioctl(struct file *filp, unsigned int cmd,
+			  unsigned long arg)
+{
+	struct inode *inode = file_inode(filp);
+	struct __fat_dirent __user *d1 = (struct __fat_dirent __user *)arg;
+	int 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(filp, cmd, arg);
+	}
+
+	/*
+	 * 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;
+
+	return fat_ioctl_readdir(inode, filp, d1, fat_ioctl_filldir,
+				 short_only, both);
+}
+
+#ifdef CONFIG_COMPAT
+#define	VFAT_IOCTL_READDIR_BOTH32	_IOR('r', 1, struct compat_dirent[2])
+#define	VFAT_IOCTL_READDIR_SHORT32	_IOR('r', 2, struct compat_dirent[2])
+
+FAT_IOCTL_FILLDIR_FUNC(fat_compat_ioctl_filldir, compat_dirent)
+
+static long fat_compat_dir_ioctl(struct file *filp, unsigned cmd,
+				 unsigned long arg)
+{
+	struct inode *inode = file_inode(filp);
+	struct compat_dirent __user *d1 = compat_ptr(arg);
+	int short_only, both;
+
+	switch (cmd) {
+	case VFAT_IOCTL_READDIR_SHORT32:
+		short_only = 1;
+		both = 0;
+		break;
+	case VFAT_IOCTL_READDIR_BOTH32:
+		short_only = 0;
+		both = 1;
+		break;
+	default:
+		return fat_generic_ioctl(filp, cmd, (unsigned long)arg);
+	}
+
+	/*
+	 * 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;
+
+	return fat_ioctl_readdir(inode, filp, d1, fat_compat_ioctl_filldir,
+				 short_only, both);
+}
+#endif /* CONFIG_COMPAT */
+
+const struct file_operations fat_dir_operations = {
+	.llseek		= generic_file_llseek,
+	.read		= generic_read_dir,
+	.iterate_shared	= fat_readdir,
+	.unlocked_ioctl	= fat_dir_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= fat_compat_dir_ioctl,
+#endif
+	.fsync		= fat_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" information
+ * for inode, nor a usable i_pos. So, this function provides some information
+ * only.
+ *
+ * Since this function walks through the on-disk inodes within a directory,
+ * callers are responsible for taking any locks necessary to prevent the
+ * directory from changing.
+ */
+int fat_get_dotdot_entry(struct inode *dir, struct buffer_head **bh,
+			 struct msdos_dir_entry **de)
+{
+	loff_t offset = 0;
+
+	*de = NULL;
+	while (fat_get_short_entry(dir, &offset, bh, de) >= 0) {
+		if (!strncmp((*de)->name, MSDOS_DOTDOT, MSDOS_NAME))
+			return 0;
+	}
+	return -ENOENT;
+}
+EXPORT_SYMBOL_GPL(fat_get_dotdot_entry);
+
+/* See if directory is empty */
+int fat_dir_empty(struct inode *dir)
+{
+	struct buffer_head *bh;
+	struct msdos_dir_entry *de;
+	loff_t cpos;
+	int result = 0;
+
+	bh = NULL;
+	cpos = 0;
+	while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
+		if (strncmp(de->name, MSDOS_DOT   , MSDOS_NAME) &&
+		    strncmp(de->name, MSDOS_DOTDOT, MSDOS_NAME)) {
+			result = -ENOTEMPTY;
+			break;
+		}
+	}
+	brelse(bh);
+	return result;
+}
+EXPORT_SYMBOL_GPL(fat_dir_empty);
+
+/*
+ * fat_subdirs counts the number of sub-directories of dir. It can be run
+ * on directories being created.
+ */
+int fat_subdirs(struct inode *dir)
+{
+	struct buffer_head *bh;
+	struct msdos_dir_entry *de;
+	loff_t cpos;
+	int count = 0;
+
+	bh = NULL;
+	cpos = 0;
+	while (fat_get_short_entry(dir, &cpos, &bh, &de) >= 0) {
+		if (de->attr & ATTR_DIR)
+			count++;
+	}
+	brelse(bh);
+	return count;
+}
+
+/*
+ * Scans a directory for a given file (name points to its formatted name).
+ * Returns an error code or zero.
+ */
+int fat_scan(struct inode *dir, const unsigned char *name,
+	     struct fat_slot_info *sinfo)
+{
+	struct super_block *sb = dir->i_sb;
+
+	sinfo->slot_off = 0;
+	sinfo->bh = NULL;
+	while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
+				   &sinfo->de) >= 0) {
+		if (!strncmp(sinfo->de->name, name, MSDOS_NAME)) {
+			sinfo->slot_off -= sizeof(*sinfo->de);
+			sinfo->nr_slots = 1;
+			sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
+			return 0;
+		}
+	}
+	return -ENOENT;
+}
+EXPORT_SYMBOL_GPL(fat_scan);
+
+/*
+ * Scans a directory for a given logstart.
+ * Returns an error code or zero.
+ */
+int fat_scan_logstart(struct inode *dir, int i_logstart,
+		      struct fat_slot_info *sinfo)
+{
+	struct super_block *sb = dir->i_sb;
+
+	sinfo->slot_off = 0;
+	sinfo->bh = NULL;
+	while (fat_get_short_entry(dir, &sinfo->slot_off, &sinfo->bh,
+				   &sinfo->de) >= 0) {
+		if (fat_get_start(MSDOS_SB(sb), sinfo->de) == i_logstart) {
+			sinfo->slot_off -= sizeof(*sinfo->de);
+			sinfo->nr_slots = 1;
+			sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
+			return 0;
+		}
+	}
+	return -ENOENT;
+}
+
+static int __fat_remove_entries(struct inode *dir, loff_t pos, int nr_slots)
+{
+	struct super_block *sb = dir->i_sb;
+	struct buffer_head *bh;
+	struct msdos_dir_entry *de, *endp;
+	int err = 0, orig_slots;
+
+	while (nr_slots) {
+		bh = NULL;
+		if (fat_get_entry(dir, &pos, &bh, &de) < 0) {
+			err = -EIO;
+			break;
+		}
+
+		orig_slots = nr_slots;
+		endp = (struct msdos_dir_entry *)(bh->b_data + sb->s_blocksize);
+		while (nr_slots && de < endp) {
+			de->name[0] = DELETED_FLAG;
+			de++;
+			nr_slots--;
+		}
+		mark_buffer_dirty_inode(bh, dir);
+		if (IS_DIRSYNC(dir))
+			err = sync_dirty_buffer(bh);
+		brelse(bh);
+		if (err)
+			break;
+
+		/* pos is *next* de's position, so this does `- sizeof(de)' */
+		pos += ((orig_slots - nr_slots) * sizeof(*de)) - sizeof(*de);
+	}
+
+	return err;
+}
+
+int fat_remove_entries(struct inode *dir, struct fat_slot_info *sinfo)
+{
+	struct super_block *sb = dir->i_sb;
+	struct msdos_dir_entry *de;
+	struct buffer_head *bh;
+	int err = 0, nr_slots;
+
+	/*
+	 * First stage: Remove the shortname. By this, the directory
+	 * entry is removed.
+	 */
+	nr_slots = sinfo->nr_slots;
+	de = sinfo->de;
+	sinfo->de = NULL;
+	bh = sinfo->bh;
+	sinfo->bh = NULL;
+	while (nr_slots && de >= (struct msdos_dir_entry *)bh->b_data) {
+		de->name[0] = DELETED_FLAG;
+		de--;
+		nr_slots--;
+	}
+	mark_buffer_dirty_inode(bh, dir);
+	if (IS_DIRSYNC(dir))
+		err = sync_dirty_buffer(bh);
+	brelse(bh);
+	if (err)
+		return err;
+	inode_inc_iversion(dir);
+
+	if (nr_slots) {
+		/*
+		 * Second stage: remove the remaining longname slots.
+		 * (This directory entry is already removed, and so return
+		 * the success)
+		 */
+		err = __fat_remove_entries(dir, sinfo->slot_off, nr_slots);
+		if (err) {
+			fat_msg(sb, KERN_WARNING,
+			       "Couldn't remove the long name slots");
+		}
+	}
+
+	fat_truncate_time(dir, NULL, S_ATIME|S_MTIME);
+	if (IS_DIRSYNC(dir))
+		(void)fat_sync_inode(dir);
+	else
+		mark_inode_dirty(dir);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(fat_remove_entries);
+
+static int fat_zeroed_cluster(struct inode *dir, sector_t blknr, int nr_used,
+			      struct buffer_head **bhs, int nr_bhs)
+{
+	struct super_block *sb = dir->i_sb;
+	sector_t last_blknr = blknr + MSDOS_SB(sb)->sec_per_clus;
+	int err, i, n;
+
+	/* Zeroing the unused blocks on this cluster */
+	blknr += nr_used;
+	n = nr_used;
+	while (blknr < last_blknr) {
+		bhs[n] = sb_getblk(sb, blknr);
+		if (!bhs[n]) {
+			err = -ENOMEM;
+			goto error;
+		}
+		/* Avoid race with userspace read via bdev */
+		lock_buffer(bhs[n]);
+		memset(bhs[n]->b_data, 0, sb->s_blocksize);
+		set_buffer_uptodate(bhs[n]);
+		unlock_buffer(bhs[n]);
+		mark_buffer_dirty_inode(bhs[n], dir);
+
+		n++;
+		blknr++;
+		if (n == nr_bhs) {
+			if (IS_DIRSYNC(dir)) {
+				err = fat_sync_bhs(bhs, n);
+				if (err)
+					goto error;
+			}
+			for (i = 0; i < n; i++)
+				brelse(bhs[i]);
+			n = 0;
+		}
+	}
+	if (IS_DIRSYNC(dir)) {
+		err = fat_sync_bhs(bhs, n);
+		if (err)
+			goto error;
+	}
+	for (i = 0; i < n; i++)
+		brelse(bhs[i]);
+
+	return 0;
+
+error:
+	for (i = 0; i < n; i++)
+		bforget(bhs[i]);
+	return err;
+}
+
+int fat_alloc_new_dir(struct inode *dir, struct timespec64 *ts)
+{
+	struct super_block *sb = dir->i_sb;
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	struct buffer_head *bhs[MAX_BUF_PER_PAGE];
+	struct msdos_dir_entry *de;
+	sector_t blknr;
+	__le16 date, time;
+	u8 time_cs;
+	int err, cluster;
+
+	err = fat_alloc_clusters(dir, &cluster, 1);
+	if (err)
+		goto error;
+
+	blknr = fat_clus_to_blknr(sbi, cluster);
+	bhs[0] = sb_getblk(sb, blknr);
+	if (!bhs[0]) {
+		err = -ENOMEM;
+		goto error_free;
+	}
+
+	fat_time_unix2fat(sbi, ts, &time, &date, &time_cs);
+
+	de = (struct msdos_dir_entry *)bhs[0]->b_data;
+	/* Avoid race with userspace read via bdev */
+	lock_buffer(bhs[0]);
+	/* filling the new directory slots ("." and ".." entries) */
+	memcpy(de[0].name, MSDOS_DOT, MSDOS_NAME);
+	memcpy(de[1].name, MSDOS_DOTDOT, MSDOS_NAME);
+	de->attr = de[1].attr = ATTR_DIR;
+	de[0].lcase = de[1].lcase = 0;
+	de[0].time = de[1].time = time;
+	de[0].date = de[1].date = date;
+	if (sbi->options.isvfat) {
+		/* extra timestamps */
+		de[0].ctime = de[1].ctime = time;
+		de[0].ctime_cs = de[1].ctime_cs = time_cs;
+		de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = date;
+	} else {
+		de[0].ctime = de[1].ctime = 0;
+		de[0].ctime_cs = de[1].ctime_cs = 0;
+		de[0].adate = de[0].cdate = de[1].adate = de[1].cdate = 0;
+	}
+	fat_set_start(&de[0], cluster);
+	fat_set_start(&de[1], MSDOS_I(dir)->i_logstart);
+	de[0].size = de[1].size = 0;
+	memset(de + 2, 0, sb->s_blocksize - 2 * sizeof(*de));
+	set_buffer_uptodate(bhs[0]);
+	unlock_buffer(bhs[0]);
+	mark_buffer_dirty_inode(bhs[0], dir);
+
+	err = fat_zeroed_cluster(dir, blknr, 1, bhs, MAX_BUF_PER_PAGE);
+	if (err)
+		goto error_free;
+
+	return cluster;
+
+error_free:
+	fat_free_clusters(dir, cluster);
+error:
+	return err;
+}
+EXPORT_SYMBOL_GPL(fat_alloc_new_dir);
+
+static int fat_add_new_entries(struct inode *dir, void *slots, int nr_slots,
+			       int *nr_cluster, struct msdos_dir_entry **de,
+			       struct buffer_head **bh, loff_t *i_pos)
+{
+	struct super_block *sb = dir->i_sb;
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	struct buffer_head *bhs[MAX_BUF_PER_PAGE];
+	sector_t blknr, start_blknr, last_blknr;
+	unsigned long size, copy;
+	int err, i, n, offset, cluster[2];
+
+	/*
+	 * The minimum cluster size is 512bytes, and maximum entry
+	 * size is 32*slots (672bytes).  So, iff the cluster size is
+	 * 512bytes, we may need two clusters.
+	 */
+	size = nr_slots * sizeof(struct msdos_dir_entry);
+	*nr_cluster = (size + (sbi->cluster_size - 1)) >> sbi->cluster_bits;
+	BUG_ON(*nr_cluster > 2);
+
+	err = fat_alloc_clusters(dir, cluster, *nr_cluster);
+	if (err)
+		goto error;
+
+	/*
+	 * First stage: Fill the directory entry.  NOTE: This cluster
+	 * is not referenced from any inode yet, so updates order is
+	 * not important.
+	 */
+	i = n = copy = 0;
+	do {
+		start_blknr = blknr = fat_clus_to_blknr(sbi, cluster[i]);
+		last_blknr = start_blknr + sbi->sec_per_clus;
+		while (blknr < last_blknr) {
+			bhs[n] = sb_getblk(sb, blknr);
+			if (!bhs[n]) {
+				err = -ENOMEM;
+				goto error_nomem;
+			}
+
+			/* fill the directory entry */
+			copy = min(size, sb->s_blocksize);
+			/* Avoid race with userspace read via bdev */
+			lock_buffer(bhs[n]);
+			memcpy(bhs[n]->b_data, slots, copy);
+			set_buffer_uptodate(bhs[n]);
+			unlock_buffer(bhs[n]);
+			mark_buffer_dirty_inode(bhs[n], dir);
+			slots += copy;
+			size -= copy;
+			if (!size)
+				break;
+			n++;
+			blknr++;
+		}
+	} while (++i < *nr_cluster);
+
+	memset(bhs[n]->b_data + copy, 0, sb->s_blocksize - copy);
+	offset = copy - sizeof(struct msdos_dir_entry);
+	get_bh(bhs[n]);
+	*bh = bhs[n];
+	*de = (struct msdos_dir_entry *)((*bh)->b_data + offset);
+	*i_pos = fat_make_i_pos(sb, *bh, *de);
+
+	/* Second stage: clear the rest of cluster, and write outs */
+	err = fat_zeroed_cluster(dir, start_blknr, ++n, bhs, MAX_BUF_PER_PAGE);
+	if (err)
+		goto error_free;
+
+	return cluster[0];
+
+error_free:
+	brelse(*bh);
+	*bh = NULL;
+	n = 0;
+error_nomem:
+	for (i = 0; i < n; i++)
+		bforget(bhs[i]);
+	fat_free_clusters(dir, cluster[0]);
+error:
+	return err;
+}
+
+int fat_add_entries(struct inode *dir, void *slots, int nr_slots,
+		    struct fat_slot_info *sinfo)
+{
+	struct super_block *sb = dir->i_sb;
+	struct msdos_sb_info *sbi = MSDOS_SB(sb);
+	struct buffer_head *bh, *prev, *bhs[3]; /* 32*slots (672bytes) */
+	struct msdos_dir_entry *de;
+	int err, free_slots, i, nr_bhs;
+	loff_t pos, i_pos;
+
+	sinfo->nr_slots = nr_slots;
+
+	/* First stage: search free directory entries */
+	free_slots = nr_bhs = 0;
+	bh = prev = NULL;
+	pos = 0;
+	err = -ENOSPC;
+	while (fat_get_entry(dir, &pos, &bh, &de) > -1) {
+		/* check the maximum size of directory */
+		if (pos >= FAT_MAX_DIR_SIZE)
+			goto error;
+
+		if (IS_FREE(de->name)) {
+			if (prev != bh) {
+				get_bh(bh);
+				bhs[nr_bhs] = prev = bh;
+				nr_bhs++;
+			}
+			free_slots++;
+			if (free_slots == nr_slots)
+				goto found;
+		} else {
+			for (i = 0; i < nr_bhs; i++)
+				brelse(bhs[i]);
+			prev = NULL;
+			free_slots = nr_bhs = 0;
+		}
+	}
+	if (dir->i_ino == MSDOS_ROOT_INO) {
+		if (!is_fat32(sbi))
+			goto error;
+	} else if (MSDOS_I(dir)->i_start == 0) {
+		fat_msg(sb, KERN_ERR, "Corrupted directory (i_pos %lld)",
+		       MSDOS_I(dir)->i_pos);
+		err = -EIO;
+		goto error;
+	}
+
+found:
+	err = 0;
+	pos -= free_slots * sizeof(*de);
+	nr_slots -= free_slots;
+	if (free_slots) {
+		/*
+		 * Second stage: filling the free entries with new entries.
+		 * NOTE: If this slots has shortname, first, we write
+		 * the long name slots, then write the short name.
+		 */
+		int size = free_slots * sizeof(*de);
+		int offset = pos & (sb->s_blocksize - 1);
+		int long_bhs = nr_bhs - (nr_slots == 0);
+
+		/* Fill the long name slots. */
+		for (i = 0; i < long_bhs; i++) {
+			int copy = min_t(int, sb->s_blocksize - offset, size);
+			memcpy(bhs[i]->b_data + offset, slots, copy);
+			mark_buffer_dirty_inode(bhs[i], dir);
+			offset = 0;
+			slots += copy;
+			size -= copy;
+		}
+		if (long_bhs && IS_DIRSYNC(dir))
+			err = fat_sync_bhs(bhs, long_bhs);
+		if (!err && i < nr_bhs) {
+			/* Fill the short name slot. */
+			int copy = min_t(int, sb->s_blocksize - offset, size);
+			memcpy(bhs[i]->b_data + offset, slots, copy);
+			mark_buffer_dirty_inode(bhs[i], dir);
+			if (IS_DIRSYNC(dir))
+				err = sync_dirty_buffer(bhs[i]);
+		}
+		for (i = 0; i < nr_bhs; i++)
+			brelse(bhs[i]);
+		if (err)
+			goto error_remove;
+	}
+
+	if (nr_slots) {
+		int cluster, nr_cluster;
+
+		/*
+		 * Third stage: allocate the cluster for new entries.
+		 * And initialize the cluster with new entries, then
+		 * add the cluster to dir.
+		 */
+		cluster = fat_add_new_entries(dir, slots, nr_slots, &nr_cluster,
+					      &de, &bh, &i_pos);
+		if (cluster < 0) {
+			err = cluster;
+			goto error_remove;
+		}
+		err = fat_chain_add(dir, cluster, nr_cluster);
+		if (err) {
+			fat_free_clusters(dir, cluster);
+			goto error_remove;
+		}
+		if (dir->i_size & (sbi->cluster_size - 1)) {
+			fat_fs_error(sb, "Odd directory size");
+			dir->i_size = (dir->i_size + sbi->cluster_size - 1)
+				& ~((loff_t)sbi->cluster_size - 1);
+		}
+		dir->i_size += nr_cluster << sbi->cluster_bits;
+		MSDOS_I(dir)->mmu_private += nr_cluster << sbi->cluster_bits;
+	}
+	sinfo->slot_off = pos;
+	sinfo->de = de;
+	sinfo->bh = bh;
+	sinfo->i_pos = fat_make_i_pos(sb, sinfo->bh, sinfo->de);
+
+	return 0;
+
+error:
+	brelse(bh);
+	for (i = 0; i < nr_bhs; i++)
+		brelse(bhs[i]);
+	return err;
+
+error_remove:
+	brelse(bh);
+	if (free_slots)
+		__fat_remove_entries(dir, pos, free_slots);
+	return err;
+}
+EXPORT_SYMBOL_GPL(fat_add_entries);