init commit via android 4.4 uboot

3 files changed, 3277 insertions, 0 deletions

diff --git a/fs/fat/Makefile b/fs/fat/Makefile
new file mode 100755
index 0000000..e462757
--- /dev/null
+++ b/fs/fat/Makefile
@@ -0,0 +1,46 @@
+#
+#
+# See file CREDITS for list of people who contributed to this
+# project.
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of
+# the License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+# MA 02111-1307 USA
+#
+
+TOPDIR=../../
+
+include $(TOPDIR)/config.mk
+
+LIB	= libfat.a
+
+AOBJS	=
+COBJS	= fat.o file.o
+
+OBJS	= $(AOBJS) $(COBJS)
+
+all:	$(LIB) $(AOBJS)
+
+$(LIB):	.depend $(OBJS)
+	$(AR) crv $@ $(OBJS)
+
+
+#########################################################################
+
+.depend:	Makefile $(AOBJS:.o=.S) $(COBJS:.o=.c)
+		$(CC) -M $(CFLAGS) $(AOBJS:.o=.S) $(COBJS:.o=.c) > $@
+
+sinclude .depend
+
+#########################################################################
diff --git a/fs/fat/fat.c b/fs/fat/fat.c
new file mode 100755
index 0000000..26c4668
--- /dev/null
+++ b/fs/fat/fat.c
@@ -0,0 +1,3023 @@
+/*++ 
+Copyright (c) 2010 WonderMedia Technologies, Inc.
+
+This program is free software: you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software 
+Foundation, either version 2 of the License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
+PARTICULAR PURPOSE.  See the GNU General Public License for more details. You
+should have received a copy of the GNU General Public License along with this
+program. If not, see http://www.gnu.org/licenses/>.
+
+WonderMedia Technologies, Inc.
+10F, 529, Chung-Cheng Road, Hsin-Tien, Taipei 231, R.O.C.
+--*/
+/*
+ * fat.c
+ *
+ * R/O (V)FAT 12/16/32 filesystem implementation by Marcus Sundberg
+ *
+ * 2002-07-28 - rjones@nexus-tech.net - ported to ppcboot v1.1.6
+ * 2003-03-10 - kharris@nexus-tech.net - ported to uboot
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <config.h>
+#include <exports.h>
+#include <fat.h>
+#include <asm/byteorder.h>
+#include <part.h>
+#include <malloc.h>
+#include <linux/compiler.h>
+
+/*
+ * Convert a string to lowercase.
+ */
+static void downcase(char *str)
+{
+	while (*str != '\0') {
+		TOLOWER(*str);
+		str++;
+	}
+}
+
+static block_dev_desc_t *cur_dev;
+static unsigned int cur_part_nr;
+static disk_partition_t cur_part_info;
+static int total_sector;
+
+
+#define DOS_BOOT_MAGIC_OFFSET	0x1fe
+#define DOS_FS_TYPE_OFFSET	0x36
+#define DOS_FS32_TYPE_OFFSET	0x52
+
+static int disk_read(__u32 block, __u32 nr_blocks, void *buf)
+{
+	if (!cur_dev || !cur_dev->block_read)
+		return -1;
+
+	return cur_dev->block_read(cur_dev->dev,
+			cur_part_info.start + block, nr_blocks, buf);
+}
+
+
+
+
+int fatpre_register_device(block_dev_desc_t * dev_desc, int part_no)
+{
+	/* First close any currently found FAT filesystem */
+	cur_dev = NULL;
+
+#if (defined(CONFIG_CMD_IDE) || \
+     defined(CONFIG_CMD_SATA) || \
+     defined(CONFIG_CMD_SCSI) || \
+     defined(CONFIG_CMD_USB) || \
+     defined(CONFIG_MMC) || \
+     defined(CONFIG_SYSTEMACE) )
+
+	/* Read the partition table, if present */
+	if (!get_partition_info(dev_desc, part_no, &cur_part_info)) {
+		cur_dev = dev_desc;
+		cur_part_nr = part_no;
+	}
+#endif
+
+	/* Otherwise it might be a superfloppy (whole-disk FAT filesystem) */
+	if (!cur_dev) {
+		/*if (part_no != 0) {
+			printf("** Partition %d not valid on device %d **\n",
+					part_no, dev_desc->dev);
+			return -1;
+		}*/
+
+		cur_dev = dev_desc;
+		cur_part_nr = 1;
+		cur_part_info.start = 0;
+		cur_part_info.size = dev_desc->lba;
+		cur_part_info.blksz = dev_desc->blksz;
+		memset(cur_part_info.name, 0, sizeof(cur_part_info.name));
+		memset(cur_part_info.type, 0, sizeof(cur_part_info.type));
+	}
+	total_sector = cur_part_info.size;
+	return 0;
+}
+
+int fat_register_device(block_dev_desc_t * dev_desc, int part_no)
+{
+	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
+#if 0
+	/* First close any currently found FAT filesystem */
+	cur_dev = NULL;
+
+#if (defined(CONFIG_CMD_IDE) || \
+     defined(CONFIG_CMD_SATA) || \
+     defined(CONFIG_CMD_SCSI) || \
+     defined(CONFIG_CMD_USB) || \
+     defined(CONFIG_MMC) || \
+     defined(CONFIG_SYSTEMACE) )
+
+	/* Read the partition table, if present */
+	if (!get_partition_info(dev_desc, part_no, &cur_part_info)) {
+		cur_dev = dev_desc;
+		cur_part_nr = part_no;
+	}
+#endif
+
+	/* Otherwise it might be a superfloppy (whole-disk FAT filesystem) */
+	if (!cur_dev) {
+		if (part_no != 0) {
+			printf("** Partition %d not valid on device %d **\n",
+					part_no, dev_desc->dev);
+			return -1;
+		}
+
+		cur_dev = dev_desc;
+		cur_part_nr = 1;
+		cur_part_info.start = 0;
+		cur_part_info.size = dev_desc->lba;
+		cur_part_info.blksz = dev_desc->blksz;
+		memset(cur_part_info.name, 0, sizeof(cur_part_info.name));
+		memset(cur_part_info.type, 0, sizeof(cur_part_info.type));
+	}
+#endif
+	if (fatpre_register_device(dev_desc, part_no))
+		return -1;
+
+	/* Make sure it has a valid FAT header */
+	if (disk_read(0, 1, buffer) != 1) {
+		cur_dev = NULL;
+		printf("Cannot read from disk\n");
+		return -1;
+	}
+
+	/* Check if it's actually a DOS volume */
+	if (memcmp(buffer + DOS_BOOT_MAGIC_OFFSET, "\x55\xAA", 2)) {
+		printf("It is not a DOS volume\n");
+		cur_dev = NULL;
+		return -1;
+	}
+
+	/* Check for FAT12/FAT16/FAT32 filesystem */
+	if (!memcmp(buffer + DOS_FS_TYPE_OFFSET, "FAT", 3))
+		return 0;
+	if (!memcmp(buffer + DOS_FS32_TYPE_OFFSET, "FAT32", 5))
+		return 0;
+
+	printf("The volume cannot be recognized\n");
+	cur_dev = NULL;
+	return -1;
+}
+
+/*
+ * Get the first occurence of a directory delimiter ('/' or '\') in a string.
+ * Return index into string if found, -1 otherwise.
+ */
+static int dirdelim(char *str)
+{
+	char *start = str;
+
+	while (*str != '\0') {
+		if (ISDIRDELIM(*str))
+			return str - start;
+		str++;
+	}
+	return -1;
+}
+
+/*
+ * Extract zero terminated short name from a directory entry.
+ */
+static void get_name(dir_entry *dirent, char *s_name)
+{
+	char *ptr;
+
+	memcpy(s_name, dirent->name, 8);
+	s_name[8] = '\0';
+	ptr = s_name;
+	while (*ptr && *ptr != ' ')
+		ptr++;
+	if (dirent->ext[0] && dirent->ext[0] != ' ') {
+		*ptr = '.';
+		ptr++;
+		memcpy(ptr, dirent->ext, 3);
+		ptr[3] = '\0';
+		while (*ptr && *ptr != ' ')
+			ptr++;
+	}
+	*ptr = '\0';
+	if (*s_name == DELETED_FLAG)
+		*s_name = '\0';
+	else if (*s_name == aRING)
+		*s_name = DELETED_FLAG;
+	downcase(s_name);
+}
+
+/*
+ * Get the entry at index 'entry' in a FAT (12/16/32) table.
+ * On failure 0x00 is returned.
+ */
+static __u32 get_fatent(fsdata *mydata, __u32 entry)
+{
+	__u32 bufnum;
+	__u32 off16, offset;
+	__u32 ret = 0x00;
+	__u16 val1, val2;
+
+	switch (mydata->fatsize) {
+	case 32:
+		bufnum = entry / FAT32BUFSIZE;
+		offset = entry - bufnum * FAT32BUFSIZE;
+		break;
+	case 16:
+		bufnum = entry / FAT16BUFSIZE;
+		offset = entry - bufnum * FAT16BUFSIZE;
+		break;
+	case 12:
+		bufnum = entry / FAT12BUFSIZE;
+		offset = entry - bufnum * FAT12BUFSIZE;
+		break;
+
+	default:
+		/* Unsupported FAT size */
+		return ret;
+	}
+
+	debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
+	       mydata->fatsize, entry, entry, offset, offset);
+
+	/* Read a new block of FAT entries into the cache. */
+	if (bufnum != mydata->fatbufnum) {
+		__u32 getsize = FATBUFBLOCKS;
+		__u8 *bufptr = mydata->fatbuf;
+		__u32 fatlength = mydata->fatlength;
+		__u32 startblock = bufnum * FATBUFBLOCKS;
+
+		if (startblock + getsize > fatlength)
+			getsize = fatlength - startblock;
+
+		startblock += mydata->fat_sect;	/* Offset from start of disk */
+
+		if (disk_read(startblock, getsize, bufptr) < 0) {
+			debug("Error reading FAT blocks\n");
+			return ret;
+		}
+		mydata->fatbufnum = bufnum;
+	}
+
+	/* Get the actual entry from the table */
+	switch (mydata->fatsize) {
+	case 32:
+		ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
+		break;
+	case 16:
+		ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
+		break;
+	case 12:
+		off16 = (offset * 3) / 4;
+
+		switch (offset & 0x3) {
+		case 0:
+			ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
+			ret &= 0xfff;
+			break;
+		case 1:
+			val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+			val1 &= 0xf000;
+			val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
+			val2 &= 0x00ff;
+			ret = (val2 << 4) | (val1 >> 12);
+			break;
+		case 2:
+			val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+			val1 &= 0xff00;
+			val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
+			val2 &= 0x000f;
+			ret = (val2 << 8) | (val1 >> 8);
+			break;
+		case 3:
+			ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+			ret = (ret & 0xfff0) >> 4;
+			break;
+		default:
+			break;
+		}
+		break;
+	}
+	debug("FAT%d: ret: %08x, offset: %04x\n",
+	       mydata->fatsize, ret, offset);
+
+	return ret;
+}
+
+/*
+ * Read at most 'size' bytes from the specified cluster into 'buffer'.
+ * Return 0 on success, -1 otherwise.
+ */
+static int
+get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size)
+{
+	__u32 idx = 0;
+	__u32 startsect;
+	int ret;
+
+	if (clustnum > 0) {
+		startsect = mydata->data_begin +
+				clustnum * mydata->clust_size;
+		if (mydata->fatsize!=32) {//this is for windows format
+			if (startsect < mydata->rootdir_sect){
+				debug("get_cluster\n");
+				startsect=mydata->rootdir_sect;
+			}
+		}
+	} else {
+		startsect = mydata->rootdir_sect;
+	}
+
+	debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
+
+	if ((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1)) {
+		ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
+
+		printf("FAT: Misaligned buffer address (%p)\n", buffer);
+
+		while (size >= mydata->sect_size) {
+			ret = disk_read(startsect++, 1, tmpbuf);
+			if (ret != 1) {
+				debug("Error reading data (got %d)\n", ret);
+				return -1;
+			}
+
+			memcpy(buffer, tmpbuf, mydata->sect_size);
+			buffer += mydata->sect_size;
+			size -= mydata->sect_size;
+		}
+	} else {
+		idx = size / mydata->sect_size;
+		ret = disk_read(startsect, idx, buffer);
+		if (ret != idx) {
+			debug("Error reading data (got %d)\n", ret);
+			return -1;
+		}
+		startsect += idx;
+		idx *= mydata->sect_size;
+		buffer += idx;
+		size -= idx;
+	}
+	if (size) {
+		ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
+
+		ret = disk_read(startsect, 1, tmpbuf);
+		if (ret != 1) {
+			debug("Error reading data (got %d)\n", ret);
+			return -1;
+		}
+
+		memcpy(buffer, tmpbuf, size);
+	}
+
+	return 0;
+}
+
+/*
+ * Read at most 'maxsize' bytes from 'pos' in the file associated with 'dentptr'
+ * into 'buffer'.
+ * Return the number of bytes read or -1 on fatal errors.
+ */
+__u8 get_contents_vfatname_block[MAX_CLUSTSIZE]
+	__aligned(ARCH_DMA_MINALIGN);
+
+static long
+get_contents(fsdata *mydata, dir_entry *dentptr, unsigned long pos,
+	     __u8 *buffer, unsigned long maxsize)
+{
+	unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
+	unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
+	__u32 curclust = START(dentptr);
+	__u32 endclust, newclust;
+	unsigned long actsize;
+
+	debug("Filesize: %ld bytes\n", filesize);
+
+	if (pos >= filesize) {
+		debug("Read position past EOF: %lu\n", pos);
+		return gotsize;
+	}
+
+	if (maxsize > 0 && filesize > pos + maxsize)
+		filesize = pos + maxsize;
+
+	debug("%ld bytes\n", filesize);
+
+	actsize = bytesperclust;
+
+	/* go to cluster at pos */
+	while (actsize <= pos) {
+		curclust = get_fatent(mydata, curclust);
+		if (CHECK_CLUST(curclust, mydata->fatsize)) {
+			debug("curclust: 0x%x\n", curclust);
+			debug("Invalid FAT entry\n");
+			return gotsize;
+		}
+		actsize += bytesperclust;
+	}
+
+	/* actsize > pos */
+	actsize -= bytesperclust;
+	filesize -= actsize;
+	pos -= actsize;
+
+	/* align to beginning of next cluster if any */
+	if (pos) {
+		actsize = min(filesize, bytesperclust);
+		if (get_cluster(mydata, curclust, get_contents_vfatname_block,
+				(int)actsize) != 0) {
+			printf("Error reading cluster\n");
+			return -1;
+		}
+		filesize -= actsize;
+		actsize -= pos;
+		memcpy(buffer, get_contents_vfatname_block + pos, actsize);
+		gotsize += actsize;
+		if (!filesize)
+			return gotsize;
+		buffer += actsize;
+
+		curclust = get_fatent(mydata, curclust);
+		if (CHECK_CLUST(curclust, mydata->fatsize)) {
+			debug("curclust: 0x%x\n", curclust);
+			debug("Invalid FAT entry\n");
+			return gotsize;
+		}
+	}
+
+	actsize = bytesperclust;
+	endclust = curclust;
+
+	do {
+		/* search for consecutive clusters */
+		while (actsize < filesize) {
+			newclust = get_fatent(mydata, endclust);
+			if ((newclust - 1) != endclust)
+				goto getit;
+			if (CHECK_CLUST(newclust, mydata->fatsize)) {
+				debug("curclust: 0x%x\n", newclust);
+				debug("Invalid FAT entry\n");
+				return gotsize;
+			}
+			endclust = newclust;
+			actsize += bytesperclust;
+		}
+
+		/* get remaining bytes */
+		actsize = filesize;
+		if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
+			printf("Error reading cluster\n");
+			return -1;
+		}
+		gotsize += actsize;
+		return gotsize;
+getit:
+		if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
+			printf("Error reading cluster\n");
+			return -1;
+		}
+		gotsize += (int)actsize;
+		filesize -= actsize;
+		buffer += actsize;
+
+		curclust = get_fatent(mydata, endclust);
+		if (CHECK_CLUST(curclust, mydata->fatsize)) {
+			debug("curclust: 0x%x\n", curclust);
+			printf("Invalid FAT entry\n");
+			return gotsize;
+		}
+		actsize = bytesperclust;
+		endclust = curclust;
+	} while (1);
+}
+
+#ifdef CONFIG_SUPPORT_VFAT
+/*
+ * Extract the file name information from 'slotptr' into 'l_name',
+ * starting at l_name[*idx].
+ * Return 1 if terminator (zero byte) is found, 0 otherwise.
+ */
+static int slot2str(dir_slot *slotptr, char *l_name, int *idx)
+{
+	int j;
+
+	for (j = 0; j <= 8; j += 2) {
+		l_name[*idx] = slotptr->name0_4[j];
+		if (l_name[*idx] == 0x00)
+			return 1;
+		(*idx)++;
+	}
+	for (j = 0; j <= 10; j += 2) {
+		l_name[*idx] = slotptr->name5_10[j];
+		if (l_name[*idx] == 0x00)
+			return 1;
+		(*idx)++;
+	}
+	for (j = 0; j <= 2; j += 2) {
+		l_name[*idx] = slotptr->name11_12[j];
+		if (l_name[*idx] == 0x00)
+			return 1;
+		(*idx)++;
+	}
+
+	return 0;
+}
+
+/*
+ * Extract the full long filename starting at 'retdent' (which is really
+ * a slot) into 'l_name'. If successful also copy the real directory entry
+ * into 'retdent'
+ * Return 0 on success, -1 otherwise.
+ */
+static int
+get_vfatname(fsdata *mydata, int curclust, __u8 *cluster,
+	     dir_entry *retdent, char *l_name)
+{
+	dir_entry *realdent;
+	dir_slot *slotptr = (dir_slot *)retdent;
+	__u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
+							PREFETCH_BLOCKS :
+							mydata->clust_size);
+	__u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
+	int idx = 0;
+
+	if (counter > VFAT_MAXSEQ) {
+		debug("Error: VFAT name is too long\n");
+		return -1;
+	}
+
+	while ((__u8 *)slotptr < buflimit) {
+		if (counter == 0)
+			break;
+		if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
+			return -1;
+		slotptr++;
+		counter--;
+	}
+
+	if ((__u8 *)slotptr >= buflimit) {
+		dir_slot *slotptr2;
+
+		if (curclust == 0)
+			return -1;
+		curclust = get_fatent(mydata, curclust);
+		if (CHECK_CLUST(curclust, mydata->fatsize)) {
+			debug("curclust: 0x%x\n", curclust);
+			printf("Invalid FAT entry\n");
+			return -1;
+		}
+
+		if (get_cluster(mydata, curclust, get_contents_vfatname_block,
+				mydata->clust_size * mydata->sect_size) != 0) {
+			debug("Error: reading directory block\n");
+			return -1;
+		}
+
+		slotptr2 = (dir_slot *)get_contents_vfatname_block;
+		while (counter > 0) {
+			if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
+			    & 0xff) != counter)
+				return -1;
+			slotptr2++;
+			counter--;
+		}
+
+		/* Save the real directory entry */
+		realdent = (dir_entry *)slotptr2;
+		while ((__u8 *)slotptr2 > get_contents_vfatname_block) {
+			slotptr2--;
+			slot2str(slotptr2, l_name, &idx);
+		}
+	} else {
+		/* Save the real directory entry */
+		realdent = (dir_entry *)slotptr;
+	}
+
+	do {
+		slotptr--;
+		if (slot2str(slotptr, l_name, &idx))
+			break;
+	} while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
+
+	l_name[idx] = '\0';
+	if (*l_name == DELETED_FLAG)
+		*l_name = '\0';
+	else if (*l_name == aRING)
+		*l_name = DELETED_FLAG;
+	downcase(l_name);
+
+	/* Return the real directory entry */
+	memcpy(retdent, realdent, sizeof(dir_entry));
+
+	return 0;
+}
+
+/* Calculate short name checksum */
+static __u8 mkcksum(const char *str)
+{
+	int i;
+
+	__u8 ret = 0;
+
+	for (i = 0; i < 11; i++) {
+		ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + str[i];
+	}
+
+	return ret;
+}
+#endif	/* CONFIG_SUPPORT_VFAT */
+
+/*
+ * Get the directory entry associated with 'filename' from the directory
+ * starting at 'startsect'
+ */
+__u8 get_dentfromdir_block[MAX_CLUSTSIZE]
+	__aligned(ARCH_DMA_MINALIGN);
+char fat_fwc[260];
+
+static dir_entry *get_dentfromdir(fsdata *mydata, int startsect,
+				  char *filename, dir_entry *retdent,
+				  int dols)
+{
+	__u16 prevcksum = 0xffff;
+	__u32 curclust = START(retdent);
+	int files = 0, dirs = 0;
+
+	debug("get_dentfromdir: %s\n", filename);
+
+	while (1) {
+		dir_entry *dentptr;
+
+		int i;
+
+		if (get_cluster(mydata, curclust, get_dentfromdir_block,
+				mydata->clust_size * mydata->sect_size) != 0) {
+			debug("Error: reading directory block\n");
+			return NULL;
+		}
+
+		dentptr = (dir_entry *)get_dentfromdir_block;
+
+		for (i = 0; i < DIRENTSPERCLUST; i++) {
+			char s_name[14], l_name[VFAT_MAXLEN_BYTES];
+
+			l_name[0] = '\0';
+			if (dentptr->name[0] == DELETED_FLAG) {
+				dentptr++;
+				continue;
+			}
+			if ((dentptr->attr & ATTR_VOLUME)) {
+#ifdef CONFIG_SUPPORT_VFAT
+				if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
+				    (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
+					prevcksum = ((dir_slot *)dentptr)->alias_checksum;
+					get_vfatname(mydata, curclust,
+						     get_dentfromdir_block,
+						     dentptr, l_name);
+					if (dols) {
+						int isdir;
+						char dirc;
+						int doit = 0;
+
+						isdir = (dentptr->attr & ATTR_DIR);
+
+						if (isdir) {
+							dirs++;
+							dirc = '/';
+							doit = 1;
+						} else {
+							dirc = ' ';
+							if (l_name[0] != 0) {
+								files++;
+								doit = 1;
+							}
+						}
+						if (doit) {
+							if (dirc == ' ') {
+								printf(" %8ld   %s%c\n",
+									(long)FAT2CPU32(dentptr->size),
+									l_name,
+									dirc);
+								if ((l_name[0] == '+') && (strstr(l_name, ".fwc") > 0)) {
+									strcpy(fat_fwc, l_name);
+								}
+							} else {
+								printf("            %s%c\n",
+									l_name,
+									dirc);
+							}
+						}
+						dentptr++;
+						continue;
+					}
+					debug("vfatname: |%s|\n", l_name);
+				} else
+#endif
+				{
+					/* Volume label or VFAT entry */
+					dentptr++;
+					continue;
+				}
+			}
+			if (dentptr->name[0] == 0) {
+				if (dols) {
+					printf("\n%d file(s), %d dir(s)\n\n",
+						files, dirs);
+				}
+				debug("Dentname == NULL - %d\n", i);
+				return NULL;
+			}
+#ifdef CONFIG_SUPPORT_VFAT
+			if (dols && mkcksum(dentptr->name) == prevcksum) {
+				prevcksum = 0xffff;
+				dentptr++;
+				continue;
+			}
+#endif
+			get_name(dentptr, s_name);
+			if (dols) {
+				int isdir = (dentptr->attr & ATTR_DIR);
+				char dirc;
+				int doit = 0;
+
+				if (isdir) {
+					dirs++;
+					dirc = '/';
+					doit = 1;
+				} else {
+					dirc = ' ';
+					if (s_name[0] != 0) {
+						files++;
+						doit = 1;
+					}
+				}
+
+				if (doit) {
+					if (dirc == ' ') {
+						printf(" %8ld   %s%c\n",
+							(long)FAT2CPU32(dentptr->size),
+							s_name, dirc);
+					} else {
+						printf("            %s%c\n",
+							s_name, dirc);
+					}
+				}
+
+				dentptr++;
+				continue;
+			}
+
+			if (strcmp(filename, s_name)
+			    && strcmp(filename, l_name)) {
+				debug("Mismatch: |%s|%s|\n", s_name, l_name);
+				dentptr++;
+				continue;
+			}
+
+			memcpy(retdent, dentptr, sizeof(dir_entry));
+
+			debug("DentName: %s", s_name);
+			debug(", start: 0x%x", START(dentptr));
+			debug(", size:  0x%x %s\n",
+			      FAT2CPU32(dentptr->size),
+			      (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
+
+			return retdent;
+		}
+
+		curclust = get_fatent(mydata, curclust);
+		if (CHECK_CLUST(curclust, mydata->fatsize)) {
+			debug("curclust: 0x%x\n", curclust);
+			printf("Invalid FAT entry\n");
+			return NULL;
+		}
+	}
+
+	return NULL;
+}
+
+/*
+ * Read boot sector and volume info from a FAT filesystem
+ */
+static int
+read_bootsectandvi(boot_sector *bs, volume_info *volinfo, int *fatsize)
+{
+	__u8 *block;
+	volume_info *vistart;
+	int ret = 0;
+
+	if (cur_dev == NULL) {
+		debug("Error: no device selected\n");
+		return -1;
+	}
+
+	block = memalign(ARCH_DMA_MINALIGN, cur_dev->blksz);
+	if (block == NULL) {
+		debug("Error: allocating block\n");
+		return -1;
+	}
+
+	if (disk_read(0, 1, block) < 0) {
+		debug("Error: reading block\n");
+		goto fail;
+	}
+
+	memcpy(bs, block, sizeof(boot_sector));
+	bs->reserved = FAT2CPU16(bs->reserved);
+	bs->fat_length = FAT2CPU16(bs->fat_length);
+	bs->secs_track = FAT2CPU16(bs->secs_track);
+	bs->heads = FAT2CPU16(bs->heads);
+	bs->total_sect = FAT2CPU32(bs->total_sect);
+
+	/* FAT32 entries */
+	if (bs->fat_length == 0) {
+		/* Assume FAT32 */
+		bs->fat32_length = FAT2CPU32(bs->fat32_length);
+		bs->flags = FAT2CPU16(bs->flags);
+		bs->root_cluster = FAT2CPU32(bs->root_cluster);
+		bs->info_sector = FAT2CPU16(bs->info_sector);
+		bs->backup_boot = FAT2CPU16(bs->backup_boot);
+		vistart = (volume_info *)(block + sizeof(boot_sector));
+		*fatsize = 32;
+	} else {
+		vistart = (volume_info *)&(bs->fat32_length);
+		*fatsize = 0;
+	}
+	memcpy(volinfo, vistart, sizeof(volume_info));
+
+	if (*fatsize == 32) {
+		if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
+			goto exit;
+	} else {
+		if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
+			*fatsize = 12;
+			goto exit;
+		}
+		if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
+			*fatsize = 16;
+			goto exit;
+		}
+	}
+
+	debug("Error: broken fs_type sign\n");
+fail:
+	ret = -1;
+exit:
+	free(block);
+	return ret;
+}
+
+__u8 do_fat_read_at_block[MAX_CLUSTSIZE]
+	__aligned(ARCH_DMA_MINALIGN);
+
+long
+do_fat_read_at(const char *filename, unsigned long pos, void *buffer,
+	       unsigned long maxsize, int dols)
+{
+	char fnamecopy[2048];
+	boot_sector bs;
+	volume_info volinfo;
+	fsdata datablock;
+	fsdata *mydata = &datablock;
+	dir_entry *dentptr = NULL;
+	__u16 prevcksum = 0xffff;
+	char *subname = "";
+	__u32 cursect;
+	int idx, isdir = 0;
+	int files = 0, dirs = 0;
+	long ret = -1;
+	int firsttime;
+	__u32 root_cluster = 0;
+	int rootdir_size = 0;
+	int j;
+
+	if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
+		debug("Error: reading boot sector\n");
+		return -1;
+	}
+
+	if (mydata->fatsize == 32) {
+		root_cluster = bs.root_cluster;
+		mydata->fatlength = bs.fat32_length;
+	} else {
+		mydata->fatlength = bs.fat_length;
+	}
+
+	mydata->fat_sect = bs.reserved;
+
+	cursect = mydata->rootdir_sect
+		= mydata->fat_sect + mydata->fatlength * bs.fats;
+
+	mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
+	mydata->clust_size = bs.cluster_size;
+	if (mydata->sect_size != cur_part_info.blksz) {
+		printf("Error: FAT sector size mismatch (fs=%hu, dev=%lu)\n",
+				mydata->sect_size, cur_part_info.blksz);
+		return -1;
+	}
+
+	if (mydata->fatsize == 32) {
+		mydata->data_begin = mydata->rootdir_sect -
+					(mydata->clust_size * 2);
+	} else {
+		rootdir_size = ((bs.dir_entries[1]  * (int)256 +
+				 bs.dir_entries[0]) *
+				 sizeof(dir_entry)) /
+				 mydata->sect_size;
+		mydata->data_begin = mydata->rootdir_sect +
+					rootdir_size -
+					(mydata->clust_size * 2);
+	}
+
+	mydata->fatbufnum = -1;
+	mydata->fatbuf = memalign(ARCH_DMA_MINALIGN, FATBUFSIZE);
+	if (mydata->fatbuf == NULL) {
+		debug("Error: allocating memory\n");
+		return -1;
+	}
+
+#ifdef CONFIG_SUPPORT_VFAT
+	debug("VFAT Support enabled\n");
+#endif
+	debug("FAT%d, fat_sect: %d, fatlength: %d\n",
+	       mydata->fatsize, mydata->fat_sect, mydata->fatlength);
+	debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
+	       "Data begins at: %d\n",
+	       root_cluster,
+	       mydata->rootdir_sect,
+	       mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
+	debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
+	      mydata->clust_size);
+
+	/* "cwd" is always the root... */
+	while (ISDIRDELIM(*filename))
+		filename++;
+
+	/* Make a copy of the filename and convert it to lowercase */
+	strcpy(fnamecopy, filename);
+	downcase(fnamecopy);
+
+	if (*fnamecopy == '\0') {
+		if (!dols)
+			goto exit;
+
+		dols = LS_ROOT;
+	} else if ((idx = dirdelim(fnamecopy)) >= 0) {
+		isdir = 1;
+		fnamecopy[idx] = '\0';
+		subname = fnamecopy + idx + 1;
+
+		/* Handle multiple delimiters */
+		while (ISDIRDELIM(*subname))
+			subname++;
+	} else if (dols) {
+		isdir = 1;
+	}
+
+	j = 0;
+	while (1) {
+		int i;
+
+		if (j == 0) {
+			debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n",
+				cursect, mydata->clust_size, DIRENTSPERBLOCK);
+
+			if (disk_read(cursect,
+					(mydata->fatsize == 32) ?
+					(mydata->clust_size) :
+					PREFETCH_BLOCKS,
+					do_fat_read_at_block) < 0) {
+				debug("Error: reading rootdir block\n");
+				goto exit;
+			}
+
+			dentptr = (dir_entry *) do_fat_read_at_block;
+		}
+
+		for (i = 0; i < DIRENTSPERBLOCK; i++) {
+			char s_name[14], l_name[VFAT_MAXLEN_BYTES];
+
+			l_name[0] = '\0';
+			if (dentptr->name[0] == DELETED_FLAG) {
+				dentptr++;
+				continue;
+			}
+			if ((dentptr->attr & ATTR_VOLUME)) {
+#ifdef CONFIG_SUPPORT_VFAT
+				if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
+				    (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
+					prevcksum =
+						((dir_slot *)dentptr)->alias_checksum;
+
+					get_vfatname(mydata,
+						     root_cluster,
+						     do_fat_read_at_block,
+						     dentptr, l_name);
+
+					if (dols == LS_ROOT) {
+						char dirc;
+						int doit = 0;
+						int isdir =
+							(dentptr->attr & ATTR_DIR);
+
+						if (isdir) {
+							dirs++;
+							dirc = '/';
+							doit = 1;
+						} else {
+							dirc = ' ';
+							if (l_name[0] != 0) {
+								files++;
+								doit = 1;
+							}
+						}
+						if (doit) {
+							if (dirc == ' ') {
+								printf(" %8ld   %s%c\n",
+									(long)FAT2CPU32(dentptr->size),
+									l_name,
+									dirc);
+							} else {
+								printf("            %s%c\n",
+									l_name,
+									dirc);
+							}
+						}
+						dentptr++;
+						continue;
+					}
+					debug("Rootvfatname: |%s|\n",
+					       l_name);
+				} else
+#endif
+				{
+					/* Volume label or VFAT entry */
+					dentptr++;
+					continue;
+				}
+			} else if (dentptr->name[0] == 0) {
+				debug("RootDentname == NULL - %d\n", i);
+				if (dols == LS_ROOT) {
+					printf("\n%d file(s), %d dir(s)\n\n",
+						files, dirs);
+					ret = 0;
+				}
+				goto exit;
+			}
+#ifdef CONFIG_SUPPORT_VFAT
+			else if (dols == LS_ROOT &&
+				 mkcksum(dentptr->name) == prevcksum) {
+				prevcksum = 0xffff;
+				dentptr++;
+				continue;
+			}
+#endif
+			get_name(dentptr, s_name);
+
+			if (dols == LS_ROOT) {
+				int isdir = (dentptr->attr & ATTR_DIR);
+				char dirc;
+				int doit = 0;
+
+				if (isdir) {
+					dirc = '/';
+					if (s_name[0] != 0) {
+						dirs++;
+						doit = 1;
+					}
+				} else {
+					dirc = ' ';
+					if (s_name[0] != 0) {
+						files++;
+						doit = 1;
+					}
+				}
+				if (doit) {
+					if (dirc == ' ') {
+						printf(" %8ld   %s%c\n",
+							(long)FAT2CPU32(dentptr->size),
+							s_name, dirc);
+					} else {
+						printf("            %s%c\n",
+							s_name, dirc);
+					}
+				}
+				dentptr++;
+				continue;
+			}
+
+			if (strcmp(fnamecopy, s_name)
+			    && strcmp(fnamecopy, l_name)) {
+				debug("RootMismatch: |%s|%s|\n", s_name,
+				       l_name);
+				dentptr++;
+				continue;
+			}
+
+			if (isdir && !(dentptr->attr & ATTR_DIR))
+				goto exit;
+
+			debug("RootName: %s", s_name);
+			debug(", start: 0x%x", START(dentptr));
+			debug(", size:  0x%x %s\n",
+			       FAT2CPU32(dentptr->size),
+			       isdir ? "(DIR)" : "");
+
+			goto rootdir_done;	/* We got a match */
+		}
+		debug("END LOOP: j=%d   clust_size=%d\n", j,
+		       mydata->clust_size);
+
+		/*
+		 * On FAT32 we must fetch the FAT entries for the next
+		 * root directory clusters when a cluster has been
+		 * completely processed.
+		 */
+		++j;
+		int rootdir_end = 0;
+		if (mydata->fatsize == 32) {
+			if (j == mydata->clust_size) {
+				int nxtsect = 0;
+				int nxt_clust = 0;
+
+				nxt_clust = get_fatent(mydata, root_cluster);
+				rootdir_end = CHECK_CLUST(nxt_clust, 32);
+
+				nxtsect = mydata->data_begin +
+					(nxt_clust * mydata->clust_size);
+
+				root_cluster = nxt_clust;
+
+				cursect = nxtsect;
+				j = 0;
+			}
+		} else {
+			if (j == PREFETCH_BLOCKS)
+				j = 0;
+
+			rootdir_end = (++cursect - mydata->rootdir_sect >=
+				       rootdir_size);
+		}
+
+		/* If end of rootdir reached */
+		if (rootdir_end) {
+			if (dols == LS_ROOT) {
+				printf("\n%d file(s), %d dir(s)\n\n",
+				       files, dirs);
+				ret = 0;
+			}
+			goto exit;
+		}
+	}
+rootdir_done:
+
+	firsttime = 1;
+
+	while (isdir) {
+		int startsect = mydata->data_begin
+			+ START(dentptr) * mydata->clust_size;
+		dir_entry dent;
+		char *nextname = NULL;
+
+		dent = *dentptr;
+		dentptr = &dent;
+
+		idx = dirdelim(subname);
+
+		if (idx >= 0) {
+			subname[idx] = '\0';
+			nextname = subname + idx + 1;
+			/* Handle multiple delimiters */
+			while (ISDIRDELIM(*nextname))
+				nextname++;
+			if (dols && *nextname == '\0')
+				firsttime = 0;
+		} else {
+			if (dols && firsttime) {
+				firsttime = 0;
+			} else {
+				isdir = 0;
+			}
+		}
+
+		if (get_dentfromdir(mydata, startsect, subname, dentptr,
+				     isdir ? 0 : dols) == NULL) {
+			if (dols && !isdir)
+				ret = 0;
+			goto exit;
+		}
+
+		if (isdir && !(dentptr->attr & ATTR_DIR))
+			goto exit;
+
+		if (idx >= 0)
+			subname = nextname;
+	}
+
+	ret = get_contents(mydata, dentptr, pos, buffer, maxsize);
+	debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
+
+exit:
+	free(mydata->fatbuf);
+	return ret;
+}
+
+long
+do_fat_read(const char *filename, void *buffer, unsigned long maxsize, int dols)
+{
+	return do_fat_read_at(filename, 0, buffer, maxsize, dols);
+}
+
+int file_fat_detectfs(void)
+{
+	boot_sector bs;
+	volume_info volinfo;
+	int fatsize;
+	char vol_label[12];
+
+	if (cur_dev == NULL) {
+		printf("No current device\n");
+		return 1;
+	}
+
+#if defined(CONFIG_CMD_IDE) || \
+    defined(CONFIG_CMD_SATA) || \
+    defined(CONFIG_CMD_SCSI) || \
+    defined(CONFIG_CMD_USB) || \
+    defined(CONFIG_MMC)
+	printf("Interface:  ");
+	switch (cur_dev->if_type) {
+	case IF_TYPE_IDE:
+		printf("IDE");
+		break;
+	case IF_TYPE_SATA:
+		printf("SATA");
+		break;
+	case IF_TYPE_SCSI:
+		printf("SCSI");
+		break;
+	case IF_TYPE_ATAPI:
+		printf("ATAPI");
+		break;
+	case IF_TYPE_USB:
+		printf("USB");
+		break;
+	case IF_TYPE_DOC:
+		printf("DOC");
+		break;
+	case IF_TYPE_MMC:
+		printf("MMC");
+		break;
+	default:
+		printf("Unknown");
+	}
+
+	printf("\n  Device %d: ", cur_dev->dev);
+	dev_print(cur_dev);
+#endif
+
+	if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
+		printf("\nNo valid FAT fs found\n");
+		return 1;
+	}
+
+	memcpy(vol_label, volinfo.volume_label, 11);
+	vol_label[11] = '\0';
+	volinfo.fs_type[5] = '\0';
+
+	printf("Partition %d: Filesystem: %s \"%s\"\n", cur_part_nr,
+		volinfo.fs_type, vol_label);
+
+	return 0;
+}
+
+int file_fat_ls(const char *dir)
+{
+	return do_fat_read(dir, NULL, 0, LS_YES);
+}
+
+long file_fat_read_at(const char *filename, unsigned long pos, void *buffer,
+		      unsigned long maxsize)
+{
+	printf("reading %s\n", filename);
+	return do_fat_read_at(filename, pos, buffer, maxsize, LS_NO);
+}
+
+long file_fat_read(const char *filename, void *buffer, unsigned long maxsize)
+{
+	return file_fat_read_at(filename, 0, buffer, maxsize);
+}
+
+static void uppercase(char *str, int len)
+{
+	int i;
+
+	for (i = 0; i < len; i++) {
+		TOUPPER(*str);
+		str++;
+	}
+}
+
+static int disk_write(__u32 block, __u32 nr_blocks, void *buf)
+{
+	if (!cur_dev || !cur_dev->block_write)
+		return -1;
+
+	if (cur_part_info.start + block + nr_blocks >
+		cur_part_info.start + total_sector) {
+		printf("error: overflow occurs\n");
+		return -1;
+	}
+
+	return cur_dev->block_write(cur_dev->dev,
+			cur_part_info.start + block, nr_blocks,	buf);
+}
+
+/*
+ * Set short name in directory entry
+ */
+static void set_name(dir_entry *dirent, const char *filename)
+{
+	char s_name[VFAT_MAXLEN_BYTES];
+	char *period;
+	int period_location, len, i, ext_num;
+
+	if (filename == NULL)
+		return;
+
+	len = strlen(filename);
+	if (len == 0)
+		return;
+
+	memcpy(s_name, filename, len);
+	uppercase(s_name, len);
+
+	period = strchr(s_name, '.');
+	if (period == NULL) {
+		period_location = len;
+		ext_num = 0;
+	} else {
+		period_location = period - s_name;
+		ext_num = len - period_location - 1;
+	}
+
+	/* Pad spaces when the length of file name is shorter than eight */
+	if (period_location < 8) {
+		memcpy(dirent->name, s_name, period_location);
+		for (i = period_location; i < 8; i++)
+			dirent->name[i] = ' ';
+	} else if (period_location == 8) {
+		memcpy(dirent->name, s_name, period_location);
+	} else {
+		memcpy(dirent->name, s_name, 6);
+		dirent->name[6] = '~';
+		dirent->name[7] = '1';
+	}
+
+	if (ext_num < 3) {
+		memcpy(dirent->ext, s_name + period_location + 1, ext_num);
+		for (i = ext_num; i < 3; i++)
+			dirent->ext[i] = ' ';
+	} else
+		memcpy(dirent->ext, s_name + period_location + 1, 3);
+
+	debug("name : %s\n", dirent->name);
+	debug("ext : %s\n", dirent->ext);
+}
+
+static __u8 num_of_fats;
+/*
+ * Write fat buffer into block device
+ */
+static int flush_fat_buffer(fsdata *mydata)
+{
+	int getsize = FATBUFBLOCKS;
+	__u32 fatlength = mydata->fatlength;
+	__u8 *bufptr = mydata->fatbuf;
+	__u32 startblock = mydata->fatbufnum * FATBUFBLOCKS;
+
+	fatlength *= mydata->sect_size;
+	startblock += mydata->fat_sect;
+
+	if (getsize > fatlength)
+		getsize = fatlength;
+
+	/* Write FAT buf */
+	if (disk_write(startblock, getsize, bufptr) < 0) {
+		debug("error: writing FAT blocks\n");
+		return -1;
+	}
+
+	if (num_of_fats == 2) {
+		/* Update corresponding second FAT blocks */
+		startblock += mydata->fatlength;
+		if (disk_write(startblock, getsize, bufptr) < 0) {
+			debug("error: writing second FAT blocks\n");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * Get the entry at index 'entry' in a FAT (12/16/32) table.
+ * On failure 0x00 is returned.
+ * When bufnum is changed, write back the previous fatbuf to the disk.
+ */
+static __u32 get_fatent_value(fsdata *mydata, __u32 entry)
+{
+	__u32 bufnum;
+	__u32 off16, offset;
+	__u32 ret = 0x00;
+	__u16 val1, val2;
+
+	switch (mydata->fatsize) {
+	case 32:
+		bufnum = entry / FAT32BUFSIZE;
+		offset = entry - bufnum * FAT32BUFSIZE;
+		break;
+	case 16:
+		bufnum = entry / FAT16BUFSIZE;
+		offset = entry - bufnum * FAT16BUFSIZE;
+		break;
+	case 12:
+		bufnum = entry / FAT12BUFSIZE;
+		offset = entry - bufnum * FAT12BUFSIZE;
+		break;
+
+	default:
+		/* Unsupported FAT size */
+		return ret;
+	}
+
+	debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
+	       mydata->fatsize, entry, entry, offset, offset);
+
+	/* Read a new block of FAT entries into the cache. */
+	if (bufnum != mydata->fatbufnum) {
+		int getsize = FATBUFBLOCKS;
+		__u8 *bufptr = mydata->fatbuf;
+		__u32 fatlength = mydata->fatlength;
+		__u32 startblock = bufnum * FATBUFBLOCKS;
+
+		if (getsize > fatlength)
+			getsize = fatlength;
+
+		fatlength *= mydata->sect_size;	/* We want it in bytes now */
+		startblock += mydata->fat_sect;	/* Offset from start of disk */
+
+		/* Write back the fatbuf to the disk */
+		if (mydata->fatbufnum != -1) {
+			if (flush_fat_buffer(mydata) < 0)
+				return -1;
+		}
+
+		if (disk_read(startblock, getsize, bufptr) < 0) {
+			debug("Error reading FAT blocks\n");
+			return ret;
+		}
+		mydata->fatbufnum = bufnum;
+	}
+
+	/* Get the actual entry from the table */
+	switch (mydata->fatsize) {
+	case 32:
+		ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
+		break;
+	case 16:
+		ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
+		break;
+	case 12:
+		off16 = (offset * 3) / 4;
+
+		switch (offset & 0x3) {
+		case 0:
+			ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
+			ret &= 0xfff;
+			break;
+		case 1:
+			val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+			val1 &= 0xf000;
+			val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
+			val2 &= 0x00ff;
+			ret = (val2 << 4) | (val1 >> 12);
+			break;
+		case 2:
+			val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+			val1 &= 0xff00;
+			val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
+			val2 &= 0x000f;
+			ret = (val2 << 8) | (val1 >> 8);
+			break;
+		case 3:
+			ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
+			ret = (ret & 0xfff0) >> 4;
+			break;
+		default:
+			break;
+		}
+		break;
+	}
+	debug("FAT%d: ret: %08x, entry: %08x, offset: %04x\n",
+	       mydata->fatsize, ret, entry, offset);
+
+	return ret;
+}
+
+#ifdef CONFIG_SUPPORT_VFAT
+/*
+ * Set the file name information from 'name' into 'slotptr',
+ */
+static int str2slot(dir_slot *slotptr, const char *name, int *idx)
+{
+	int j, end_idx = 0;
+
+	for (j = 0; j <= 8; j += 2) {
+		if (name[*idx] == 0x00) {
+			slotptr->name0_4[j] = 0;
+			slotptr->name0_4[j + 1] = 0;
+			end_idx++;
+			goto name0_4;
+		}
+		slotptr->name0_4[j] = name[*idx];
+		(*idx)++;
+		end_idx++;
+	}
+	for (j = 0; j <= 10; j += 2) {
+		if (name[*idx] == 0x00) {
+			slotptr->name5_10[j] = 0;
+			slotptr->name5_10[j + 1] = 0;
+			end_idx++;
+			goto name5_10;
+		}
+		slotptr->name5_10[j] = name[*idx];
+		(*idx)++;
+		end_idx++;
+	}
+	for (j = 0; j <= 2; j += 2) {
+		if (name[*idx] == 0x00) {
+			slotptr->name11_12[j] = 0;
+			slotptr->name11_12[j + 1] = 0;
+			end_idx++;
+			goto name11_12;
+		}
+		slotptr->name11_12[j] = name[*idx];
+		(*idx)++;
+		end_idx++;
+	}
+
+	if (name[*idx] == 0x00)
+		return 1;
+
+	return 0;
+/* Not used characters are filled with 0xff 0xff */
+name0_4:
+	for (; end_idx < 5; end_idx++) {
+		slotptr->name0_4[end_idx * 2] = 0xff;
+		slotptr->name0_4[end_idx * 2 + 1] = 0xff;
+	}
+	end_idx = 5;
+name5_10:
+	end_idx -= 5;
+	for (; end_idx < 6; end_idx++) {
+		slotptr->name5_10[end_idx * 2] = 0xff;
+		slotptr->name5_10[end_idx * 2 + 1] = 0xff;
+	}
+	end_idx = 11;
+name11_12:
+	end_idx -= 11;
+	for (; end_idx < 2; end_idx++) {
+		slotptr->name11_12[end_idx * 2] = 0xff;
+		slotptr->name11_12[end_idx * 2 + 1] = 0xff;
+	}
+
+	return 1;
+}
+
+static int is_next_clust(fsdata *mydata, dir_entry *dentptr);
+static void flush_dir_table(fsdata *mydata, dir_entry **dentptr);
+
+/*
+ * Fill dir_slot entries with appropriate name, id, and attr
+ * The real directory entry is returned by 'dentptr'
+ */
+static void
+fill_dir_slot(fsdata *mydata, dir_entry **dentptr, const char *l_name)
+{
+	dir_slot *slotptr = (dir_slot *)get_contents_vfatname_block;
+	__u8 counter = 0, checksum;
+	int idx = 0, ret;
+	char s_name[16];
+
+	/* Get short file name and checksum value */
+	strncpy(s_name, (*dentptr)->name, 16);
+	checksum = mkcksum(s_name);
+
+	do {
+		memset(slotptr, 0x00, sizeof(dir_slot));
+		ret = str2slot(slotptr, l_name, &idx);
+		slotptr->id = ++counter;
+		slotptr->attr = ATTR_VFAT;
+		slotptr->alias_checksum = checksum;
+		slotptr++;
+	} while (ret == 0);
+
+	slotptr--;
+	slotptr->id |= LAST_LONG_ENTRY_MASK;
+
+	while (counter >= 1) {
+		if (is_next_clust(mydata, *dentptr)) {
+			/* A new cluster is allocated for directory table */
+			flush_dir_table(mydata, dentptr);
+		}
+		memcpy(*dentptr, slotptr, sizeof(dir_slot));
+		(*dentptr)++;
+		slotptr--;
+		counter--;
+	}
+
+	if (is_next_clust(mydata, *dentptr)) {
+		/* A new cluster is allocated for directory table */
+		flush_dir_table(mydata, dentptr);
+	}
+}
+
+static __u32 dir_curclust;
+
+/*
+ * Extract the full long filename starting at 'retdent' (which is really
+ * a slot) into 'l_name'. If successful also copy the real directory entry
+ * into 'retdent'
+ * If additional adjacent cluster for directory entries is read into memory,
+ * then 'get_contents_vfatname_block' is copied into 'get_dentfromdir_block' and
+ * the location of the real directory entry is returned by 'retdent'
+ * Return 0 on success, -1 otherwise.
+ */
+static int
+get_long_file_name(fsdata *mydata, int curclust, __u8 *cluster,
+	      dir_entry **retdent, char *l_name)
+{
+	dir_entry *realdent;
+	dir_slot *slotptr = (dir_slot *)(*retdent);
+	dir_slot *slotptr2 = NULL;
+	__u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
+							PREFETCH_BLOCKS :
+							mydata->clust_size);
+	__u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
+	int idx = 0, cur_position = 0;
+
+	if (counter > VFAT_MAXSEQ) {
+		debug("Error: VFAT name is too long\n");
+		return -1;
+	}
+
+	while ((__u8 *)slotptr < buflimit) {
+		if (counter == 0)
+			break;
+		if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
+			return -1;
+		slotptr++;
+		counter--;
+	}
+
+	if ((__u8 *)slotptr >= buflimit) {
+		if (curclust == 0)
+			return -1;
+		curclust = get_fatent_value(mydata, dir_curclust);
+		if (CHECK_CLUST(curclust, mydata->fatsize)) {
+			debug("curclust: 0x%x\n", curclust);
+			printf("Invalid FAT entry\n");
+			return -1;
+		}
+
+		dir_curclust = curclust;
+
+		if (get_cluster(mydata, curclust, get_contents_vfatname_block,
+				mydata->clust_size * mydata->sect_size) != 0) {
+			debug("Error: reading directory block\n");
+			return -1;
+		}
+
+		slotptr2 = (dir_slot *)get_contents_vfatname_block;
+		while (counter > 0) {
+			if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
+			    & 0xff) != counter)
+				return -1;
+			slotptr2++;
+			counter--;
+		}
+
+		/* Save the real directory entry */
+		realdent = (dir_entry *)slotptr2;
+		while ((__u8 *)slotptr2 > get_contents_vfatname_block) {
+			slotptr2--;
+			slot2str(slotptr2, l_name, &idx);
+		}
+	} else {
+		/* Save the real directory entry */
+		realdent = (dir_entry *)slotptr;
+	}
+
+	do {
+		slotptr--;
+		if (slot2str(slotptr, l_name, &idx))
+			break;
+	} while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
+
+	l_name[idx] = '\0';
+	if (*l_name == DELETED_FLAG)
+		*l_name = '\0';
+	else if (*l_name == aRING)
+		*l_name = DELETED_FLAG;
+	downcase(l_name);
+
+	/* Return the real directory entry */
+	*retdent = realdent;
+
+	if (slotptr2) {
+		memcpy(get_dentfromdir_block, get_contents_vfatname_block,
+			mydata->clust_size * mydata->sect_size);
+		cur_position = (__u8 *)realdent - get_contents_vfatname_block;
+		*retdent = (dir_entry *) &get_dentfromdir_block[cur_position];
+	}
+
+	return 0;
+}
+
+#endif
+
+/*
+ * Set the entry at index 'entry' in a FAT (16/32) table.
+ */
+static int set_fatent_value(fsdata *mydata, __u32 entry, __u32 entry_value)
+{
+	__u32 bufnum, offset;
+	__u32 off16;
+	__u16 val;
+	
+	switch (mydata->fatsize) {
+	case 32:
+		bufnum = entry / FAT32BUFSIZE;
+		offset = entry - bufnum * FAT32BUFSIZE;
+		break;
+	case 16:
+		bufnum = entry / FAT16BUFSIZE;
+		offset = entry - bufnum * FAT16BUFSIZE;
+		break;
+	case 12:
+		bufnum = entry / FAT12BUFSIZE;
+		offset = entry - bufnum * FAT12BUFSIZE;
+		break;
+	default:
+		/* Unsupported FAT size */
+		return -1;
+	}
+
+	/* Read a new block of FAT entries into the cache. */
+	if (bufnum != mydata->fatbufnum) {
+		int getsize = FATBUFBLOCKS;
+		__u8 *bufptr = mydata->fatbuf;
+		__u32 fatlength = mydata->fatlength;
+		__u32 startblock = bufnum * FATBUFBLOCKS;
+
+		fatlength *= mydata->sect_size;
+		startblock += mydata->fat_sect;
+
+		if (getsize > fatlength)
+			getsize = fatlength;
+
+		if (mydata->fatbufnum != -1) {
+			if (flush_fat_buffer(mydata) < 0)
+				return -1;
+		}
+
+		if (disk_read(startblock, getsize, bufptr) < 0) {
+			debug("Error reading FAT blocks\n");
+			return -1;
+		}
+		mydata->fatbufnum = bufnum;
+	}
+
+	/* Set the actual entry */
+	switch (mydata->fatsize) {
+	case 32:
+		((__u32 *) mydata->fatbuf)[offset] = cpu_to_le32(entry_value);
+		break;
+	case 16:
+		((__u16 *) mydata->fatbuf)[offset] = cpu_to_le16(entry_value);
+		break;
+	case 12:
+		off16 = (offset * 3) / 4;
+
+		switch (offset & 0x3) {
+		case 0:
+			val = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]&0xf000);
+			((__u16 *) mydata->fatbuf)[off16]= val|(cpu_to_le16(entry_value)&0x0fff);		
+			break;
+		case 1:
+			val = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]&0x0fff);
+			((__u16 *)mydata->fatbuf)[off16] =val|((cpu_to_le16(entry_value)&0x000f)<<12);
+			val = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]&0xff00);
+			((__u16 *)mydata->fatbuf)[off16+1] =val|((cpu_to_le16(entry_value)&0x0ff0)>>4);
+			break;
+		case 2:
+			val = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]&0x00ff);
+			((__u16 *)mydata->fatbuf)[off16] =val|((cpu_to_le16(entry_value)&0x00ff)<<8);
+			val = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]&0xfff0);
+			((__u16 *)mydata->fatbuf)[off16+1] =val|((cpu_to_le16(entry_value)&0x0f00)>>8);
+			break;
+		case 3:
+			val = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]&0x000f);
+			((__u16 *) mydata->fatbuf)[off16]= val|((cpu_to_le16(entry_value)&0x0fff)<<4);		
+			break;
+		default:
+			break;
+		}
+		break;
+	default:
+		return -1;
+	}
+
+	return 0;
+}
+
+/*
+ * Determine the entry value at index 'entry' in a FAT (16/32) table
+ */
+static __u32 determine_fatent(fsdata *mydata, __u32 entry)
+{
+	__u32 next_fat, next_entry = entry + 1;
+
+	while (1) {
+		next_fat = get_fatent_value(mydata, next_entry);
+		if (next_fat == 0) {
+			set_fatent_value(mydata, entry, next_entry);
+			break;
+		}
+		next_entry++;
+	}
+	debug("FAT%d: entry: %08x, entry_value: %04x\n",
+	       mydata->fatsize, entry, next_entry);
+
+	return next_entry;
+}
+
+/*
+ * Write at most 'size' bytes from 'buffer' into the specified cluster.
+ * Return 0 on success, -1 otherwise.
+ */
+static int
+set_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer,
+	     unsigned long size)
+{
+	int idx = 0;
+	__u32 startsect;
+
+	if (clustnum > 0) {
+		startsect = mydata->data_begin +
+				clustnum * mydata->clust_size;
+		
+		if (mydata->fatsize!=32) {//this is for windows format
+			if (startsect < mydata->rootdir_sect){
+				debug("set_cluster\n");
+				startsect=mydata->rootdir_sect;
+			}
+		}
+	}
+	else
+		startsect = mydata->rootdir_sect;
+
+	debug("clustnum: %d, startsect: %d\n", clustnum, startsect);
+
+	if (disk_write(startsect, size / mydata->sect_size, buffer) < 0) {
+		debug("Error writing data\n");
+		return -1;
+	}
+
+	if (size % mydata->sect_size) {
+		__u8 tmpbuf[mydata->sect_size];
+
+		idx = size / mydata->sect_size;
+		buffer += idx * mydata->sect_size;
+		memcpy(tmpbuf, buffer, size % mydata->sect_size);
+
+		if (disk_write(startsect + idx, 1, tmpbuf) < 0) {
+			debug("Error writing data\n");
+			return -1;
+		}
+
+		return 0;
+	}
+
+	return 0;
+}
+
+/*
+ * Find the first empty cluster
+ */
+static int find_empty_cluster(fsdata *mydata)
+{
+	__u32 fat_val, entry = 3;
+
+	while (1) {
+		fat_val = get_fatent_value(mydata, entry);
+		if (fat_val == 0)
+			break;
+		entry++;
+	}
+
+	return entry;
+}
+
+/*
+ * Write directory entries in 'get_dentfromdir_block' to block device
+ */
+static void flush_dir_table(fsdata *mydata, dir_entry **dentptr)
+{
+	int dir_newclust = 0;
+
+	if (set_cluster(mydata, dir_curclust,
+		    get_dentfromdir_block,
+		    mydata->clust_size * mydata->sect_size) != 0) {
+		printf("error: wrinting directory entry\n");
+		return;
+	}
+	dir_newclust = find_empty_cluster(mydata);
+	set_fatent_value(mydata, dir_curclust, dir_newclust);
+	if (mydata->fatsize == 32)
+		set_fatent_value(mydata, dir_newclust, 0xffffff8);
+	else if (mydata->fatsize == 16)
+		set_fatent_value(mydata, dir_newclust, 0xfff8);
+	else if (mydata->fatsize == 12)
+		set_fatent_value(mydata, dir_newclust, 0xff8);
+
+	dir_curclust = dir_newclust;
+
+	if (flush_fat_buffer(mydata) < 0)
+		return;
+
+	memset(get_dentfromdir_block, 0x00,
+		mydata->clust_size * mydata->sect_size);
+
+	*dentptr = (dir_entry *) get_dentfromdir_block;
+}
+
+/*
+ * Set empty cluster from 'entry' to the end of a file
+ */
+static int clear_fatent(fsdata *mydata, __u32 entry)
+{
+	__u32 fat_val;
+
+	while (1) {
+		fat_val = get_fatent_value(mydata, entry);
+		if (fat_val != 0)
+			set_fatent_value(mydata, entry, 0);
+		else
+			break;
+
+		if (fat_val == 0xfffffff || fat_val == 0xffff)
+			break;
+
+		entry = fat_val;
+	}
+
+	/* Flush fat buffer */
+	if (flush_fat_buffer(mydata) < 0)
+		return -1;
+
+	return 0;
+}
+
+/*
+ * Write at most 'maxsize' bytes from 'buffer' into
+ * the file associated with 'dentptr'
+ * Return the number of bytes read or -1 on fatal errors.
+ */
+static int
+set_contents(fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
+	      unsigned long maxsize)
+{
+	unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
+	unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
+	__u32 curclust = START(dentptr);
+	__u32 endclust = 0, newclust = 0;
+	unsigned long actsize;
+
+	debug("Filesize: %ld bytes\n", filesize);
+	if (maxsize > 0 && filesize > maxsize)
+		filesize = maxsize;
+
+	debug("%ld bytes\n", filesize);
+
+	actsize = bytesperclust;
+	endclust = curclust;
+	do {
+		/* search for consecutive clusters */
+		while (actsize < filesize) {
+			newclust = determine_fatent(mydata, endclust);
+
+			if ((newclust - 1) != endclust)
+				goto getit;
+
+			if (CHECK_CLUST(newclust, mydata->fatsize)) {
+				debug("curclust: 0x%x\n", newclust);
+				debug("Invalid FAT entry\n");
+				return gotsize;
+			}
+			endclust = newclust;
+			actsize += bytesperclust;
+		}
+		/* actsize >= file size */
+		actsize -= bytesperclust;
+		/* set remaining clusters */
+		if (set_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
+			debug("error: writing cluster\n");
+			return -1;
+		}
+
+		/* set remaining bytes */
+		gotsize += (int)actsize;
+		filesize -= actsize;
+		buffer += actsize;
+		actsize = filesize;
+
+		if (set_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
+			debug("error: writing cluster\n");
+			return -1;
+		}
+		gotsize += actsize;
+
+		/* Mark end of file in FAT */
+		if (mydata->fatsize == 16)
+			newclust = 0xffff;
+		else if (mydata->fatsize == 32)
+			newclust = 0xfffffff;
+		else if (mydata->fatsize == 12)
+			newclust = 0x0fff;
+		debug("fatsize %d\n", mydata->fatsize);
+		debug("data_begin 0x%x fatlength 0x%x fat_sect 0x%x clust_size 0x%x\n", 
+			mydata->data_begin, mydata->fatlength, mydata->fat_sect,
+			mydata->clust_size);
+
+			
+		set_fatent_value(mydata, endclust, newclust);
+		debug("rootdir_sect 0x%x\n", mydata->rootdir_sect);
+
+		return gotsize;
+getit:
+		if (set_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
+			debug("error: writing cluster\n");
+			return -1;
+		}
+		gotsize += (int)actsize;
+		filesize -= actsize;
+		buffer += actsize;
+
+		if (CHECK_CLUST(curclust, mydata->fatsize)) {
+			debug("curclust: 0x%x\n", curclust);
+			debug("Invalid FAT entry\n");
+			return gotsize;
+		}
+		actsize = bytesperclust;
+		curclust = endclust = newclust;
+	} while (1);
+}
+
+/*
+ * Fill dir_entry
+ */
+static void fill_dentry(fsdata *mydata, dir_entry *dentptr,
+	const char *filename, __u32 start_cluster, __u32 size, __u8 attr)
+{
+	if (mydata->fatsize == 32)
+		dentptr->starthi =
+			cpu_to_le16((start_cluster & 0xffff0000) >> 16);
+	dentptr->start = cpu_to_le16(start_cluster & 0xffff);
+	dentptr->size = cpu_to_le32(size);
+
+	dentptr->attr = attr;
+
+	set_name(dentptr, filename);
+}
+
+/*
+ * Check whether adding a file makes the file system to
+ * exceed the size of the block device
+ * Return -1 when overflow occurs, otherwise return 0
+ */
+static int check_overflow(fsdata *mydata, __u32 clustnum, unsigned long size)
+{
+	__u32 startsect, sect_num;
+
+	if (clustnum > 0) {
+		startsect = mydata->data_begin +
+				clustnum * mydata->clust_size;
+		
+		if (mydata->fatsize!=32) {//this is for windows format
+			if (startsect < mydata->rootdir_sect) {
+				debug("check_overflow\n");
+				startsect=mydata->rootdir_sect;
+			}
+		}
+	} else {
+		startsect = mydata->rootdir_sect;
+	}
+
+	sect_num = size / mydata->sect_size;
+	if (size % mydata->sect_size)
+		sect_num++;
+
+	if (startsect + sect_num > cur_part_info.start + total_sector)
+		return -1;
+
+	return 0;
+}
+
+/*
+ * Check if adding several entries exceed one cluster boundary
+ */
+static int is_next_clust(fsdata *mydata, dir_entry *dentptr)
+{
+	int cur_position;
+
+	cur_position = (__u8 *)dentptr - get_dentfromdir_block;
+
+	if (cur_position >= mydata->clust_size * mydata->sect_size)
+		return 1;
+	else
+		return 0;
+}
+
+static dir_entry *empty_dentptr;
+/*
+ * Find a directory entry based on filename or start cluster number
+ * If the directory entry is not found,
+ * the new position for writing a directory entry will be returned
+ */
+static dir_entry *find_directory_entry(fsdata *mydata, int startsect,
+	char *filename, dir_entry *retdent, __u32 start)
+{
+	__u32 curclust = (startsect - mydata->data_begin) / mydata->clust_size;
+	//if (mydata->fatsize != 32) {
+	//	curclust=0;
+	//}
+	debug("get_dentfromdir: %s\n", filename);
+
+	while (1) {
+		dir_entry *dentptr;
+
+		int i;
+
+		if (get_cluster(mydata, curclust, get_dentfromdir_block,
+			    mydata->clust_size * mydata->sect_size) != 0) {
+			printf("Error: reading directory block\n");
+			return NULL;
+		}
+
+		dentptr = (dir_entry *)get_dentfromdir_block;
+
+		dir_curclust = curclust;
+
+		for (i = 0; i < DIRENTSPERCLUST; i++) {
+			char s_name[14], l_name[VFAT_MAXLEN_BYTES];
+
+			l_name[0] = '\0';
+			if (dentptr->name[0] == DELETED_FLAG) {
+				dentptr++;
+				if (is_next_clust(mydata, dentptr))
+					break;
+				continue;
+			}
+			if ((dentptr->attr & ATTR_VOLUME)) {
+#ifdef CONFIG_SUPPORT_VFAT
+				if ((dentptr->attr & ATTR_VFAT) &&
+				    (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
+					get_long_file_name(mydata, curclust,
+						     get_dentfromdir_block,
+						     &dentptr, l_name);
+					debug("vfatname: |%s|\n", l_name);
+				} else
+#endif
+				{
+					/* Volume label or VFAT entry */
+					dentptr++;
+					if (is_next_clust(mydata, dentptr))
+						break;
+					continue;
+				}
+			}
+			if (dentptr->name[0] == 0) {
+				debug("Dentname == NULL - %d\n", i);
+				empty_dentptr = dentptr;
+				return NULL;
+			}
+
+			get_name(dentptr, s_name);
+
+			if (strcmp(filename, s_name)
+			    && strcmp(filename, l_name)) {
+				debug("Mismatch: |%s|%s|\n",
+					s_name, l_name);
+				dentptr++;
+				if (is_next_clust(mydata, dentptr))
+					break;
+				continue;
+			}
+
+			memcpy(retdent, dentptr, sizeof(dir_entry));
+
+			debug("DentName: %s", s_name);
+			debug(", start: 0x%x", START(dentptr));
+			debug(", size:  0x%x %s\n",
+			      FAT2CPU32(dentptr->size),
+			      (dentptr->attr & ATTR_DIR) ?
+			      "(DIR)" : "");
+
+			return dentptr;
+		}
+
+		curclust = get_fatent_value(mydata, dir_curclust);
+		if ((curclust >= 0xffffff8) || (curclust >= 0xfff8)) {
+			empty_dentptr = dentptr;
+			return NULL;
+		}
+		if (CHECK_CLUST(curclust, mydata->fatsize)) {
+			debug("curclust: 0x%x\n", curclust);
+			debug("Invalid FAT entry\n");
+			return NULL;
+		}
+	}
+
+	return NULL;
+}
+
+static int do_fat_write(const char *filename, void *buffer,
+	unsigned long size)
+{
+	dir_entry *dentptr, *retdent;
+	__u32 startsect;
+	__u32 start_cluster;
+	boot_sector bs;
+	volume_info volinfo;
+	fsdata datablock;
+	fsdata *mydata = &datablock;
+	int cursect;
+	int ret = -1, name_len;
+	char l_filename[VFAT_MAXLEN_BYTES];
+	int write_size = size;
+
+	dir_curclust = 0;
+
+	if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
+		debug("error: reading boot sector\n");
+		return -1;
+	}
+
+	total_sector = bs.total_sect;
+	if (total_sector == 0)
+		total_sector = cur_part_info.size;
+
+	if (mydata->fatsize == 32)
+		mydata->fatlength = bs.fat32_length;
+	else
+		mydata->fatlength = bs.fat_length;
+
+	mydata->fat_sect = bs.reserved;
+
+	cursect = mydata->rootdir_sect
+		= mydata->fat_sect + mydata->fatlength * bs.fats;
+	debug("fat_sect %d numfat %d\n", mydata->fat_sect, bs.fats);
+	num_of_fats = bs.fats;
+
+	mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
+	mydata->clust_size = bs.cluster_size;
+
+	if (mydata->fatsize == 32) {
+		mydata->data_begin = mydata->rootdir_sect -
+					(mydata->clust_size * 2);
+	} else {
+		int rootdir_size;
+
+		rootdir_size = ((bs.dir_entries[1]  * (int)256 +
+				 bs.dir_entries[0]) *
+				 sizeof(dir_entry)) /
+				 mydata->sect_size;
+		debug("rootdir_size 0x%x\n",rootdir_size);
+		mydata->data_begin = mydata->rootdir_sect +
+					rootdir_size -
+					(mydata->clust_size * 2);
+		debug("pre data_begin 0x%x\n", mydata->data_begin);
+	}
+	
+	mydata->fatbufnum = -1;
+	mydata->fatbuf = malloc(FATBUFSIZE);
+	if (mydata->fatbuf == NULL) {
+		debug("Error: allocating memory\n");
+		return -1;
+	}
+
+	if (disk_read(cursect,
+		(mydata->fatsize == 32) ?
+		(mydata->clust_size) :
+		PREFETCH_BLOCKS, do_fat_read_at_block) < 0) {
+		debug("Error: reading rootdir block\n");
+		goto exit;
+	}
+	dentptr = (dir_entry *) do_fat_read_at_block;
+
+	name_len = strlen(filename);
+	if (name_len >= VFAT_MAXLEN_BYTES)
+		name_len = VFAT_MAXLEN_BYTES - 1;
+
+	memcpy(l_filename, filename, name_len);
+	l_filename[name_len] = 0; /* terminate the string */
+	downcase(l_filename);
+
+	startsect = mydata->rootdir_sect;
+	debug("mydata->roodir_sect %d\n", startsect);
+	retdent = find_directory_entry(mydata, startsect,
+				l_filename, dentptr, 0);
+	if (retdent) {
+		/* Update file size and start_cluster in a directory entry */
+		retdent->size = cpu_to_le32(size);
+		start_cluster = FAT2CPU16(retdent->start);
+		if (mydata->fatsize == 32)
+			start_cluster |=
+				(FAT2CPU16(retdent->starthi) << 16);
+
+		ret = check_overflow(mydata, start_cluster, size);
+		if (ret) {
+			printf("Error: %ld overflow\n", size);
+			goto exit;
+		}
+
+		ret = clear_fatent(mydata, start_cluster);
+		if (ret) {
+			printf("Error: clearing FAT entries\n");
+			goto exit;
+		}
+
+		ret = set_contents(mydata, retdent, buffer, size);
+		if (ret < 0) {
+			printf("Error: writing contents\n");
+			goto exit;
+		}
+		write_size = ret;
+		debug("attempt to write 0x%x bytes\n", write_size);
+
+		/* Flush fat buffer */
+		ret = flush_fat_buffer(mydata);
+		if (ret) {
+			printf("Error: flush fat buffer\n");
+			goto exit;
+		}
+
+		/* Write directory table to device */
+		ret = set_cluster(mydata, dir_curclust,
+			    get_dentfromdir_block,
+			    mydata->clust_size * mydata->sect_size);
+		if (ret) {
+			printf("Error: writing directory entry\n");
+			goto exit;
+		}
+	} else {
+		/* Set short name to set alias checksum field in dir_slot */
+		set_name(empty_dentptr, filename);
+		fill_dir_slot(mydata, &empty_dentptr, filename);
+
+		ret = start_cluster = find_empty_cluster(mydata);
+		if (ret < 0) {
+			printf("Error: finding empty cluster\n");
+			goto exit;
+		}
+
+		ret = check_overflow(mydata, start_cluster, size);
+		if (ret) {
+			printf("Error: %ld overflow\n", size);
+			goto exit;
+		}
+
+		/* Set attribute as archieve for regular file */
+		fill_dentry(mydata, empty_dentptr, filename,
+			start_cluster, size, 0x20);
+
+		ret = set_contents(mydata, empty_dentptr, buffer, size);
+		if (ret < 0) {
+			printf("Error: writing contents\n");
+			goto exit;
+		}
+		write_size = ret;
+		debug("attempt to write 0x%x bytes\n", write_size);
+
+		/* Flush fat buffer */
+		ret = flush_fat_buffer(mydata);
+		if (ret) {
+			printf("Error: flush fat buffer\n");
+			goto exit;
+		}
+
+		/* Write directory table to device */
+		ret = set_cluster(mydata, dir_curclust,
+			    get_dentfromdir_block,
+			    mydata->clust_size * mydata->sect_size);
+		if (ret) {
+			printf("Error: writing directory entry\n");
+			goto exit;
+		}
+	}
+
+exit:
+	free(mydata->fatbuf);
+	return ret < 0 ? ret : write_size;
+}
+
+int file_fat_write(const char *filename, void *buffer, unsigned long maxsize)
+{
+	printf("writing %s\n", filename);
+	return do_fat_write(filename, buffer, maxsize);
+}
+
+
+
+
+
+enum {
+// Perhaps this should remain constant
+	info_sector_number = 1,
+// TODO: make these cmdline options
+// dont forget sanity check: backup_boot_sector + 3 <= reserved_sect
+	backup_boot_sector = 3,
+	reserved_sect      = 6,
+};
+
+#define	NUM_FATS        2
+#define MAX_CLUST_32    0x0FFFFFF0
+#define MAX_CLUST_12    0x0FF0
+
+#define FAT_FSINFO_SIG1 0x41615252
+#define FAT_FSINFO_SIG2 0x61417272
+#define BOOT_SIGN 0xAA55
+#define MARK_CLUSTER(cluster, value) \
+	((uint32_t *)fat)[cluster] = cpu_to_le32(value)
+#define EOF_FAT32       0x0FFFFFF8
+#define reserved_sect16or12 1
+
+int
+format_fat32(void)
+{
+	uint32_t sect_per_clust=1;
+	uint32_t sect_per_fat=1;
+	uint32_t total_clust;
+	const char *volume_label = "";
+	unsigned bufsize = reserved_sect;
+	void *buffer;
+	boot_sector32 *bs;
+	fat32_fsinfo *fsinfo;
+
+	if ((!strcmp(cur_part_info.type, "5")) ||
+			(!strcmp(cur_part_info.type, "15"))||
+			(!strcmp(cur_part_info.type, "133"))){
+		printf("Cannot format extended partition!\n");
+		return -1;
+	}
+
+
+
+	/* For FAT32, try to do the same as M$'s format command
+	 * (see http://www.win.tue.nl/~aeb/linux/fs/fat/fatgen103.pdf p. 20):
+	 * fs size <= 260M: 0.5k clusters
+	 * fs size <=	8G: 4k clusters
+	 * fs size <=  16G: 8k clusters
+	 * fs size >   16G: 16k clusters
+	 */
+	if (cur_part_info.size< 32.5*1024*2) {
+		printf("The size of the device is too small for FAT32, please use FAT16/FAT12\n");
+		return -1;
+	} else if (cur_part_info.size> 260*1024*2) {
+		sect_per_clust=8;
+		if (cur_part_info.size>8*1024*1024*2) {
+			sect_per_clust=16;
+			if (cur_part_info.size>16*1024*1024*2) {
+				sect_per_clust=32;
+				if (cur_part_info.size>32*1024*1024*2) {
+					sect_per_clust=64;
+					if (cur_part_info.size>2*1024*1024*1024*2) {
+						printf("FAT32 doesn't support larger than 2T\n");
+						return -1;
+					}
+				}
+			}
+		}
+		
+	}
+	sect_per_fat = 1;
+	while (1) {
+		while (1) {
+			int spf_adj;
+			unsigned int tcl = (cur_part_info.size - reserved_sect - NUM_FATS * sect_per_fat) / sect_per_clust;
+			// tcl may be > MAX_CLUST_32 here, but it may be
+			// because sect_per_fat is underestimated,
+			// and with increased sect_per_fat it still may become
+			// <= MAX_CLUST_32. Therefore, we do not check
+			// against MAX_CLUST_32, but against a bigger const:
+			if (tcl > 0x80ffffff)
+				goto next;
+			total_clust = tcl; // fits in uint32_t
+			// Every cluster needs 4 bytes in FAT. +2 entries since
+			// FAT has space for non-existent clusters 0 and 1.
+			// Let's see how many sectors that needs.
+			//May overflow at "*4":
+			//spf_adj = ((total_clust+2) * 4 + bytes_per_sect-1) / bytes_per_sect - sect_per_fat;
+			//Same in the more obscure, non-overflowing form:
+			spf_adj = ((total_clust+2) + (512/4)-1) / (512/4) - sect_per_fat;
+#if 0
+			printf("sect_per_clust:%u sect_per_fat:%u total_clust:%u",
+					sect_per_clust, sect_per_fat, (int)tcl);
+			printf("adjust to sect_per_fat:%d", spf_adj);
+#endif
+			if (spf_adj <= 0) {
+				// do not need to adjust sect_per_fat.
+				// so, was total_clust too big after all?
+				if (total_clust <= MAX_CLUST_32)
+					goto found_total_clust; // no
+				// yes, total_clust is _a bit_ too big
+				goto next;
+			}
+			// adjust sect_per_fat, go back and recalc total_clust
+			// (note: just "sect_per_fat += spf_adj" isn't ok)
+			sect_per_fat += ((unsigned)spf_adj / 2) | 1;
+		}
+ next:
+		if (sect_per_clust == 128) {
+			printf("can't make FAT32 with >128 sectors/cluster");
+			return -1;
+		}
+		sect_per_clust *= 2;
+		sect_per_fat = (sect_per_fat / 2) | 1;
+	}
+found_total_clust:	
+
+
+	bufsize |= 2; // use this instead
+	bufsize |= sect_per_clust;
+	//printf("buffer size is 0x%x\n", bufsize);
+	buffer = memalign(ARCH_DMA_MINALIGN, bufsize*512);
+	if (buffer == NULL) {
+		printf("Error: allocating block\n");
+		return -1;
+	}
+
+
+	memset(buffer, 0, bufsize*512);
+	bs=(void*)buffer;
+	fsinfo=(void*)(buffer + 512);
+	
+	strcpy(bs->ignored, "\xeb\x58\x90" "MSWIN4.1"); // system_id[8] included :)
+	STORE_LE(bs->sector_size[0], 0x00);//(__u16)cur_part_info.blksz);
+	STORE_LE(bs->sector_size[1], 0x02);//(__u16)cur_part_info.blksz);
+	STORE_LE(bs->cluster_size, (__u8)sect_per_clust);
+	// cast in needed on big endian to suppress a warning
+	STORE_LE(bs->reserved, (uint16_t)reserved_sect);
+	STORE_LE(bs->fats, 2);
+	//STORE_LE(bs->dir_entries[0], 0); // for FAT32, stays 0
+	//STORE_LE(bs->dir_entries[1], 0); // for FAT32, stays 0
+	//if (cur_part_info.size <= 0xffff) {
+	//	STORE_LE(bs->sectors[0], (__u8)(cur_part_info.size&0xff));
+	//	STORE_LE(bs->sectors[1], (__u8)((cur_part_info.size&0xff00)>>8));
+	//}
+	STORE_LE(bs->media, 0xf8);
+	//STORE_LE(bs->fat_length, 0);
+	STORE_LE(bs->secs_track, 63);
+	STORE_LE(bs->heads, 255);
+	STORE_LE(bs->hidden, 0);
+	STORE_LE(bs->total_sect, cur_part_info.size);
+	STORE_LE(bs->fat32_length, sect_per_fat);
+	STORE_LE(bs->flags, 0);
+	//STORE_LE(bs->version[0], 0);
+	//STORE_LE(bs->version[1], 0);
+	STORE_LE(bs->root_cluster, 2);
+	STORE_LE(bs->info_sector, info_sector_number);
+	STORE_LE(bs->backup_boot, backup_boot_sector);
+	//STORE_LE(bs->reserved2[0], 0);
+	//STORE_LE(bs->reserved2[1], 0);
+	//STORE_LE(bs->reserved2[2], 0);
+	//STORE_LE(bs->reserved2[3], 0);
+	//STORE_LE(bs->reserved2[4], 0);
+	//STORE_LE(bs->reserved2[5], 0);
+	STORE_LE(bs->boot_signature, 0x29);
+	//STORE_LE(bs->volumeID[0], 0);
+	//STORE_LE(bs->volumeID[1], 0);
+	//STORE_LE(bs->volumeID[2], 0);
+	//STORE_LE(bs->volumeID[3], 0);
+	strncpy(bs->filesystype, "FAT32   ", sizeof(bs->filesystype));
+	strncpy(bs->volumelabel, volume_label, sizeof(bs->volumelabel));
+	
+	STORE_LE(fsinfo->signature1, FAT_FSINFO_SIG1);
+	STORE_LE(fsinfo->signature2, FAT_FSINFO_SIG2);
+	// we've allocated cluster 2 for the root dir
+	STORE_LE(fsinfo->free_clusters, (total_clust - 1));
+	STORE_LE(fsinfo->next_cluster, 2);
+	STORE_LE(fsinfo->boot_sign, BOOT_SIGN);
+
+	//set reserved region
+	{
+		*((__u8*)bs+510)=0x55;
+		*((__u8*)bs+511)=0xAA;	
+		*((__u8*)fsinfo+510)=0x55;
+		*((__u8*)fsinfo+511)=0xAA;
+		if (disk_write(0, backup_boot_sector, bs) < 0) {
+			printf("Error: writing block\n");
+			goto fail;
+		}
+		if (disk_write(backup_boot_sector, reserved_sect - backup_boot_sector, bs) < 0) {
+			printf("Error: writing block\n");
+			goto fail;
+		}
+	}
+	
+	//set fat
+	{
+		unsigned i=0,j=0;
+		unsigned char *fat = (void*)buffer;
+		memset(bs, 0, 512 * 2);
+		// initial FAT entries
+		MARK_CLUSTER(0, 0x0fffff00 | 0xf8);
+		MARK_CLUSTER(1, 0xffffffff);
+		// mark cluster 2 as EOF (used for root dir)
+		MARK_CLUSTER(2, EOF_FAT32);
+		for (i = 0; i < NUM_FATS; i++) {
+			if (disk_write(reserved_sect+i*sect_per_fat, 1, buffer) < 0) {
+				printf("Error: writing block\n");
+				goto fail;
+			}
+			for (j = 1; j < sect_per_fat; j++)
+				if (disk_write(reserved_sect+i*sect_per_fat+j, 1, buffer+512) < 0) {
+					printf("Error: writing block\n");
+					goto fail;
+				}
+		}
+		memset(buffer, 0, sect_per_clust * 512);
+		for(j=0;j<sect_per_clust;j++)
+			if (disk_write(reserved_sect+i*sect_per_fat+j, 1, buffer) < 0) {
+					printf("Error: writing block\n");
+					goto fail;
+				}
+	}
+	
+	free(buffer);
+	printf("succeed\n");
+	return 0;
+fail:
+	printf("failed\n");
+	free(buffer);
+	return -1;
+}
+
+static void mark_FAT_cluster(char size_fat, char* fat, int cluster, unsigned int value)
+{
+    switch (size_fat) {
+    case 12:
+	value &= 0x0fff;
+	if (((cluster * 3) & 0x1) == 0) {
+	    fat[3 * cluster / 2] = (unsigned char)(value & 0x00ff);
+	    fat[(3 * cluster / 2) + 1] =
+		(unsigned char)((fat[(3 * cluster / 2) + 1] & 0x00f0)
+				| ((value & 0x0f00) >> 8));
+	} else {
+	    fat[3 * cluster / 2] =
+		(unsigned char)((fat[3 * cluster / 2] & 0x000f) |
+				((value & 0x000f) << 4));
+	    fat[(3 * cluster / 2) + 1] = (unsigned char)((value & 0x0ff0) >> 4);
+	}
+	break;
+
+    case 16:
+	value &= 0xffff;
+	fat[2 * cluster] = (unsigned char)(value & 0x00ff);
+	fat[(2 * cluster) + 1] = (unsigned char)(value >> 8);
+	break;
+
+    case 32:
+	value &= 0xfffffff;
+	fat[4 * cluster] = (unsigned char)(value & 0x000000ff);
+	fat[(4 * cluster) + 1] = (unsigned char)((value & 0x0000ff00) >> 8);
+	fat[(4 * cluster) + 2] = (unsigned char)((value & 0x00ff0000) >> 16);
+	fat[(4 * cluster) + 3] = (unsigned char)((value & 0xff000000) >> 24);
+	break;
+
+    default:
+	printf("Bad FAT size (not 12, 16, or 32)\n");
+    }
+}
+
+
+int
+format_fat16(void)
+{
+	uint32_t sect_per_clust=1;
+	uint32_t sect_per_fat=1;
+	uint32_t total_clust;
+	const char *volume_label = "";
+	unsigned bufsize = reserved_sect;
+	void *buffer;
+	boot_sector16or12 *bs;
+
+	if ((!strcmp(cur_part_info.type, "5")) ||
+			(!strcmp(cur_part_info.type, "15"))||
+			(!strcmp(cur_part_info.type, "133"))){
+		printf("Cannot format extended partition!\n");
+		return -1;
+	}
+
+
+	/* For FAT32, try to do the same as M$'s format command
+	 * (see http://www.win.tue.nl/~aeb/linux/fs/fat/fatgen103.pdf p. 20):
+	 * fs size <= 260M: 0.5k clusters
+	 * fs size <=	8G: 4k clusters
+	 * fs size <=  16G: 8k clusters
+	 * fs size >   16G: 16k clusters
+	 */
+	if (cur_part_info.size< 4.1*1024*2) {
+		printf("The size of the device is too small for FAT16, please use FAT12\n");
+		return -1;
+	} else if (cur_part_info.size> 16*1024*2) {
+		sect_per_clust=4;
+		if (cur_part_info.size>128*1024*2) {
+			sect_per_clust=8;
+			if (cur_part_info.size>256*1024*2) {
+				sect_per_clust=16;
+				if (cur_part_info.size>512*1024*2) {
+					sect_per_clust=32;
+					if (cur_part_info.size>1024*1024*2) {
+						sect_per_clust=64;
+						if (cur_part_info.size>2*1024*1024*2){
+							printf("FAT16 doesn't support larger than 2G\n");
+							return -1;
+						}
+					}
+					
+				}
+			}
+		}
+		
+	}
+	//we have to decide sect_per_fat
+	{
+		unsigned int RootDirSectors = ((512*32)+(512-1))/512;
+		unsigned int TmpVal1 = cur_part_info.size-(1+RootDirSectors);
+		unsigned int TmpVal2 = (256*sect_per_clust)+2;;
+		unsigned int FATSz = (TmpVal1+TmpVal2-1)/TmpVal2;
+		sect_per_fat = FATSz;
+	}
+
+
+	debug("sect_per_fat 0x%x\n", sect_per_fat);
+	debug("sect_per_clust 0x%x\n", sect_per_clust);
+	bufsize |= 2; // use this instead
+	bufsize |= sect_per_clust;
+	buffer = memalign(ARCH_DMA_MINALIGN, bufsize*512);
+	if (buffer == NULL) {
+		printf("Error: allocating block\n");
+		return -1;
+	}
+
+
+	memset(buffer, 0, bufsize*512);
+	bs=(void*)buffer;
+	
+	strcpy(bs->ignored, "\xeb\x58\x90" "MSWIN4.1"); // system_id[8] included :)
+	STORE_LE(bs->sector_size[0], 0x00);//(__u16)cur_part_info.blksz);
+	STORE_LE(bs->sector_size[1], 0x02);//(__u16)cur_part_info.blksz);
+	STORE_LE(bs->cluster_size, (__u8)sect_per_clust);
+	// cast in needed on big endian to suppress a warning
+	STORE_LE(bs->reserved, 1);
+	STORE_LE(bs->fats, 2);
+	STORE_LE(bs->dir_entries[0], 0x00); 
+	STORE_LE(bs->dir_entries[1], 0x02); 
+	if (cur_part_info.size <= 0xffff) {
+		STORE_LE(bs->sectors[0], (__u8)(cur_part_info.size&0xff));
+		STORE_LE(bs->sectors[1], (__u8)((cur_part_info.size&0xff00)>>8));
+	}
+	STORE_LE(bs->media, 0xf8);
+	STORE_LE(bs->fat_length, sect_per_fat);
+	STORE_LE(bs->secs_track, 63);
+	STORE_LE(bs->heads, 255);
+	STORE_LE(bs->hidden, 0);
+	STORE_LE(bs->total_sect, cur_part_info.size);
+	STORE_LE(bs->drive_number, 0);
+	STORE_LE(bs->boot_signature, 0x29);
+	//STORE_LE(bs->volumeID[0], 0);
+	//STORE_LE(bs->volumeID[1], 0);
+	//STORE_LE(bs->volumeID[2], 0);
+	//STORE_LE(bs->volumeID[3], 0);
+	strncpy(bs->filesystype, "FAT16   ", sizeof(bs->filesystype));
+	strncpy(bs->volumelabel, volume_label, sizeof(bs->volumelabel));
+	
+
+	//set reserved region
+	{
+		*((__u8*)bs+510)=0x55;
+		*((__u8*)bs+511)=0xAA;	
+		if (disk_write(0, 1, bs) < 0) {
+			printf("Error: writing block\n");
+			goto fail;
+		}
+	}
+	
+	
+	{
+		//set fat
+		unsigned i=0,j=0;
+		unsigned char *fat = (void*)buffer;
+		memset(bs, 0, 512 * 2);
+		// initial FAT entries
+		mark_FAT_cluster(16, fat, 0, 0xfffffff8);
+		mark_FAT_cluster(16, fat, 1, 0xffffffff);
+		for (i = 0; i < NUM_FATS; i++) {
+			if (disk_write(1+i*sect_per_fat, 1, buffer) < 0) {
+				printf("Error: writing block\n");
+				goto fail;
+			}
+			for (j = 1; j < sect_per_fat; j++)
+				if (disk_write(1+i*sect_per_fat+j, 1, buffer+512) < 0) {
+					printf("Error: writing block\n");
+					goto fail;
+				}
+		}
+		
+		//set root directory region
+		
+		memset(buffer, 0, 512);
+		for(j=0;j<32;j++)
+			if (disk_write(1+NUM_FATS*sect_per_fat+j, 1, buffer) < 0) {
+					printf("Error: writing block\n");
+					goto fail;
+			}
+	}
+	
+	free(buffer);
+	printf("succeed\n");
+	return 0;
+fail:
+	printf("failed\n");
+	free(buffer);
+	return -1;
+}
+
+int
+format_fat12(void)
+{
+		uint32_t sect_per_clust=0x40;
+		uint32_t sect_per_fat=1;
+		uint32_t total_clust;
+		const char *volume_label = "";
+		unsigned bufsize = reserved_sect;
+		void *buffer;
+		boot_sector16or12 *bs;
+
+		if ((!strcmp(cur_part_info.type, "5")) ||
+				(!strcmp(cur_part_info.type, "15"))||
+				(!strcmp(cur_part_info.type, "133"))){
+			printf("Cannot format extended partition!\n");
+			return -1;
+		}
+
+
+	
+		/* For FAT32, try to do the same as M$'s format command
+		 * (see http://www.win.tue.nl/~aeb/linux/fs/fat/fatgen103.pdf p. 20):
+		 * fs size <= 260M: 0.5k clusters
+		 * fs size <=	8G: 4k clusters
+		 * fs size <=  16G: 8k clusters
+		 * fs size >   16G: 16k clusters
+		 */
+		if (cur_part_info.size > 255*63) {
+			printf("The size is larger than 7.8MB, Please use the FAT16/FAT32\n");
+			return -1;
+		}
+
+		//we have to decide sect_per_fat
+		sect_per_fat=0x0c;	
+		sect_per_clust=4;
+	
+		bufsize |= 2; // use this instead
+		bufsize |= sect_per_clust;
+		buffer = memalign(ARCH_DMA_MINALIGN, bufsize*512);
+		if (buffer == NULL) {
+			printf("Error: allocating block\n");
+			return -1;
+		}
+	
+	
+		memset(buffer, 0, bufsize*512);
+		bs=(void*)buffer;
+		
+		strcpy(bs->ignored, "\xeb\x58\x90" "MSWIN4.1"); // system_id[8] included :)
+		STORE_LE(bs->sector_size[0], 0x00);//(__u16)cur_part_info.blksz);
+		STORE_LE(bs->sector_size[1], 0x02);//(__u16)cur_part_info.blksz);
+		STORE_LE(bs->cluster_size, (__u8)sect_per_clust);
+		// cast in needed on big endian to suppress a warning
+		STORE_LE(bs->reserved, sect_per_clust);
+		STORE_LE(bs->fats, 2);
+		STORE_LE(bs->dir_entries[0], 0x00); 
+		STORE_LE(bs->dir_entries[1], 0x02); 
+		if (cur_part_info.size <= 0xffff) {
+			STORE_LE(bs->sectors[0], (__u8)(cur_part_info.size&0xff));
+			STORE_LE(bs->sectors[1], (__u8)((cur_part_info.size&0xff00)>>8));
+		}
+		STORE_LE(bs->media, 0xf8);
+		STORE_LE(bs->fat_length, sect_per_fat);
+		STORE_LE(bs->secs_track, 63);
+		STORE_LE(bs->heads, 255);
+		STORE_LE(bs->hidden, 0);
+		STORE_LE(bs->total_sect, cur_part_info.size);
+		STORE_LE(bs->drive_number, 0);
+		STORE_LE(bs->boot_signature, 0x29);
+		//STORE_LE(bs->volumeID[0], 0);
+		//STORE_LE(bs->volumeID[1], 0);
+		//STORE_LE(bs->volumeID[2], 0);
+		//STORE_LE(bs->volumeID[3], 0);
+		strncpy(bs->filesystype, "FAT12   ", sizeof(bs->filesystype));
+		strncpy(bs->volumelabel, volume_label, sizeof(bs->volumelabel));
+		
+	
+		//set reserved region
+		{
+			*((__u8*)bs+510)=0x55;
+			*((__u8*)bs+511)=0xAA;	
+			if (disk_write(0, 1, bs) < 0) {
+				printf("Error: writing block\n");
+				goto fail;
+			}
+		}
+		
+		
+		{
+			//set fat
+			unsigned i=0,j=0;
+			unsigned int reserver12=sect_per_clust;
+			unsigned char *fat = (void*)buffer;
+			memset(bs, 0, 512 * 2);
+			// initial FAT entries
+			mark_FAT_cluster(12, fat, 0, 0xfffffff8);
+			mark_FAT_cluster(12, fat, 1, 0xffffffff);
+			
+			for (i = 0; i < NUM_FATS; i++) {
+				if (disk_write(reserver12+i*sect_per_fat, 1, buffer) < 0) {
+					printf("Error: writing block\n");
+					goto fail;
+				}
+				for (j = 1; j < sect_per_fat; j++)
+					if (disk_write(reserver12+i*sect_per_fat+j, 1, buffer+512) < 0) {
+						printf("Error: writing block\n");
+						goto fail;
+					}
+			}
+			
+			//set root directory region
+			
+			memset(buffer, 0, 512);
+			for(j=0;j<32;j++)
+				if (disk_write(reserver12+NUM_FATS*sect_per_fat+j, 1, buffer) < 0) {
+						printf("Error: writing block\n");
+						goto fail;
+				}
+		}
+		
+		free(buffer);
+		printf("succeed\n");
+		return 0;
+	fail:
+		printf("failed\n");
+		free(buffer);
+		return -1;
+
+}
+
diff --git a/fs/fat/file.c b/fs/fat/file.c
new file mode 100755
index 0000000..f999ac5
--- /dev/null
+++ b/fs/fat/file.c
@@ -0,0 +1,208 @@
+/*
+ * file.c
+ *
+ * Mini "VFS" by Marcus Sundberg
+ *
+ * 2002-07-28 - rjones@nexus-tech.net - ported to ppcboot v1.1.6
+ * 2003-03-10 - kharris@nexus-tech.net - ported to uboot
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <config.h>
+#include <malloc.h>
+#include <fat.h>
+#include <linux/stat.h>
+#include <linux/time.h>
+
+#if (CONFIG_COMMANDS & CFG_CMD_FAT)
+
+/* Supported filesystems */
+static const struct filesystem filesystems[] = {
+	{ file_fat_detectfs,  file_fat_ls,  file_fat_read,  "FAT" },
+};
+#define NUM_FILESYS	(sizeof(filesystems)/sizeof(struct filesystem))
+
+/* The filesystem which was last detected */
+static int current_filesystem = FSTYPE_NONE;
+
+/* The current working directory */
+#define CWD_LEN		511
+char file_cwd[CWD_LEN+1] = "/";
+
+const char *
+file_getfsname(int idx)
+{
+	if (idx < 0 || idx >= NUM_FILESYS) return NULL;
+
+	return filesystems[idx].name;
+}
+
+
+static void
+pathcpy(char *dest, const char *src)
+{
+	char *origdest = dest;
+
+	do {
+		if (dest-file_cwd >= CWD_LEN) {
+			*dest = '\0';
+			return;
+		}
+		*(dest) = *(src);
+		if (*src == '\0') {
+			if (dest-- != origdest && ISDIRDELIM(*dest)) {
+				*dest = '\0';
+			}
+			return;
+		}
+		++dest;
+		if (ISDIRDELIM(*src)) {
+			while (ISDIRDELIM(*src)) src++;
+		} else {
+			src++;
+		}
+	} while (1);
+}
+
+
+int
+file_cd(const char *path)
+{
+	if (ISDIRDELIM(*path)) {
+		while (ISDIRDELIM(*path)) path++;
+		strncpy(file_cwd+1, path, CWD_LEN-1);
+	} else {
+		const char *origpath = path;
+		char *tmpstr = file_cwd;
+		int back = 0;
+
+		while (*tmpstr != '\0') tmpstr++;
+		do {
+			tmpstr--;
+		} while (ISDIRDELIM(*tmpstr));
+
+		while (*path == '.') {
+			path++;
+			while (*path == '.') {
+				path++;
+				back++;
+			}
+			if (*path != '\0' && !ISDIRDELIM(*path)) {
+				path = origpath;
+				back = 0;
+				break;
+			}
+			while (ISDIRDELIM(*path)) path++;
+			origpath = path;
+		}
+
+		while (back--) {
+			/* Strip off path component */
+			while (!ISDIRDELIM(*tmpstr)) {
+				tmpstr--;
+			}
+			if (tmpstr == file_cwd) {
+				/* Incremented again right after the loop. */
+				tmpstr--;
+				break;
+			}
+			/* Skip delimiters */
+			while (ISDIRDELIM(*tmpstr)) tmpstr--;
+		}
+		tmpstr++;
+		if (*path == '\0') {
+			if (tmpstr == file_cwd) {
+				*tmpstr = '/';
+				tmpstr++;
+			}
+			*tmpstr = '\0';
+			return 0;
+		}
+		*tmpstr = '/';
+		pathcpy(tmpstr+1, path);
+	}
+
+	return 0;
+}
+
+
+int
+file_detectfs(void)
+{
+	int i;
+
+	current_filesystem = FSTYPE_NONE;
+
+	for (i = 0; i < NUM_FILESYS; i++) {
+		if (filesystems[i].detect() == 0) {
+			strcpy(file_cwd, "/");
+			current_filesystem = i;
+			break;
+		}
+	}
+
+	return current_filesystem;
+}
+
+
+int
+file_ls(const char *dir)
+{
+	char fullpath[1024];
+	const char *arg;
+
+	if (current_filesystem == FSTYPE_NONE) {
+		printf("Can't list files without a filesystem!\n");
+		return -1;
+	}
+
+	if (ISDIRDELIM(*dir)) {
+		arg = dir;
+	} else {
+		sprintf(fullpath, "%s/%s", file_cwd, dir);
+		arg = fullpath;
+	}
+	return filesystems[current_filesystem].ls(arg);
+}
+
+
+long
+file_read(const char *filename, void *buffer, unsigned long maxsize)
+{
+	char fullpath[1024];
+	const char *arg;
+
+	if (current_filesystem == FSTYPE_NONE) {
+		printf("Can't load file without a filesystem!\n");
+		return -1;
+	}
+
+	if (ISDIRDELIM(*filename)) {
+		arg = filename;
+	} else {
+		sprintf(fullpath, "%s/%s", file_cwd, filename);
+		arg = fullpath;
+	}
+
+	return filesystems[current_filesystem].read(arg, buffer, maxsize);
+}
+
+#endif /* #if (CONFIG_COMMANDS & CFG_CMD_FAT) */