Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / fat / dir.c
diff --git a/kernel/fs/fat/dir.c b/kernel/fs/fat/dir.c
new file mode 100644 (file)
index 0000000..4afc4d9
--- /dev/null
@@ -0,0 +1,1402 @@
+/*
+ *  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 "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 ((sbi->fat_bits != 32) && (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:
+       if (*bh)
+               brelse(*bh);
+
+       *bh = NULL;
+       iblock = *pos >> sb->s_blocksize_bits;
+       err = fat_bmap(dir, iblock, &phys, &mapped_blocks, 0);
+       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:
+       slots = 0;
+       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));
+       /* see namei.c, msdos_format_name */
+       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) {
+                       ctx->pos = cpos;
+                       ret = status;
+                       goto out;
+               } 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:
+       if (!fake_offset)
+               ctx->pos = cpos - (nr_slots + 1) * sizeof(struct msdos_dir_entry);
+
+       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:
+       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 int 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 -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;                                                    \
+}
+
+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;
+       mutex_lock(&inode->i_mutex);
+       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;
+       }
+       mutex_unlock(&inode->i_mutex);
+       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);
+       }
+
+       if (!access_ok(VERIFY_WRITE, d1, sizeof(struct __fat_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;
+
+       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);
+       }
+
+       if (!access_ok(VERIFY_WRITE, d1, sizeof(struct compat_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;
+
+       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        = 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;
+       dir->i_version++;
+
+       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");
+               }
+       }
+
+       dir->i_mtime = dir->i_atime = CURRENT_TIME_SEC;
+       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;
+               }
+               memset(bhs[n]->b_data, 0, sb->s_blocksize);
+               set_buffer_uptodate(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 timespec *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;
+       /* 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]);
+       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);
+                       memcpy(bhs[n]->b_data, slots, copy);
+                       slots += copy;
+                       size -= copy;
+                       set_buffer_uptodate(bhs[n]);
+                       mark_buffer_dirty_inode(bhs[n], dir);
+                       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 *uninitialized_var(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 (sbi->fat_bits != 32)
+                       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);