diff --git a/fs/udf/unicode.c b/fs/udf/unicode.c
new file mode 100644
index 0000000..5fcfa96
--- /dev/null
+++ b/fs/udf/unicode.c
@@ -0,0 +1,402 @@
+/*
+ * unicode.c
+ *
+ * PURPOSE
+ *	Routines for converting between UTF-8 and OSTA Compressed Unicode.
+ *      Also handles filename mangling
+ *
+ * DESCRIPTION
+ *	OSTA Compressed Unicode is explained in the OSTA UDF specification.
+ *		http://www.osta.org/
+ *	UTF-8 is explained in the IETF RFC XXXX.
+ *		ftp://ftp.internic.net/rfc/rfcxxxx.txt
+ *
+ * COPYRIGHT
+ *	This file is distributed under the terms of the GNU General Public
+ *	License (GPL). Copies of the GPL can be obtained from:
+ *		ftp://prep.ai.mit.edu/pub/gnu/GPL
+ *	Each contributing author retains all rights to their own work.
+ */
+
+#include "udfdecl.h"
+
+#include <linux/kernel.h>
+#include <linux/string.h>	/* for memset */
+#include <linux/nls.h>
+#include <linux/crc-itu-t.h>
+#include <linux/slab.h>
+
+#include "udf_sb.h"
+
+#define PLANE_SIZE 0x10000
+#define UNICODE_MAX 0x10ffff
+#define SURROGATE_MASK 0xfffff800
+#define SURROGATE_PAIR 0x0000d800
+#define SURROGATE_LOW  0x00000400
+#define SURROGATE_CHAR_BITS 10
+#define SURROGATE_CHAR_MASK ((1 << SURROGATE_CHAR_BITS) - 1)
+
+#define ILLEGAL_CHAR_MARK	'_'
+#define EXT_MARK		'.'
+#define CRC_MARK		'#'
+#define EXT_SIZE		5
+/* Number of chars we need to store generated CRC to make filename unique */
+#define CRC_LEN			5
+
+static unicode_t get_utf16_char(const uint8_t *str_i, int str_i_max_len,
+				int str_i_idx, int u_ch, unicode_t *ret)
+{
+	unicode_t c;
+	int start_idx = str_i_idx;
+
+	/* Expand OSTA compressed Unicode to Unicode */
+	c = str_i[str_i_idx++];
+	if (u_ch > 1)
+		c = (c << 8) | str_i[str_i_idx++];
+	if ((c & SURROGATE_MASK) == SURROGATE_PAIR) {
+		unicode_t next;
+
+		/* Trailing surrogate char */
+		if (str_i_idx >= str_i_max_len) {
+			c = UNICODE_MAX + 1;
+			goto out;
+		}
+
+		/* Low surrogate must follow the high one... */
+		if (c & SURROGATE_LOW) {
+			c = UNICODE_MAX + 1;
+			goto out;
+		}
+
+		WARN_ON_ONCE(u_ch != 2);
+		next = str_i[str_i_idx++] << 8;
+		next |= str_i[str_i_idx++];
+		if ((next & SURROGATE_MASK) != SURROGATE_PAIR ||
+		    !(next & SURROGATE_LOW)) {
+			c = UNICODE_MAX + 1;
+			goto out;
+		}
+
+		c = PLANE_SIZE +
+		    ((c & SURROGATE_CHAR_MASK) << SURROGATE_CHAR_BITS) +
+		    (next & SURROGATE_CHAR_MASK);
+	}
+out:
+	*ret = c;
+	return str_i_idx - start_idx;
+}
+
+
+static int udf_name_conv_char(uint8_t *str_o, int str_o_max_len,
+			      int *str_o_idx,
+			      const uint8_t *str_i, int str_i_max_len,
+			      int *str_i_idx,
+			      int u_ch, int *needsCRC,
+			      int (*conv_f)(wchar_t, unsigned char *, int),
+			      int translate)
+{
+	unicode_t c;
+	int illChar = 0;
+	int len, gotch = 0;
+
+	while (!gotch && *str_i_idx < str_i_max_len) {
+		if (*str_o_idx >= str_o_max_len) {
+			*needsCRC = 1;
+			return gotch;
+		}
+
+		len = get_utf16_char(str_i, str_i_max_len, *str_i_idx, u_ch,
+				     &c);
+		/* These chars cannot be converted. Replace them. */
+		if (c == 0 || c > UNICODE_MAX || (conv_f && c > MAX_WCHAR_T) ||
+		    (translate && c == '/')) {
+			illChar = 1;
+			if (!translate)
+				gotch = 1;
+		} else if (illChar)
+			break;
+		else
+			gotch = 1;
+		*str_i_idx += len;
+	}
+	if (illChar) {
+		*needsCRC = 1;
+		c = ILLEGAL_CHAR_MARK;
+		gotch = 1;
+	}
+	if (gotch) {
+		if (conv_f) {
+			len = conv_f(c, &str_o[*str_o_idx],
+				     str_o_max_len - *str_o_idx);
+		} else {
+			len = utf32_to_utf8(c, &str_o[*str_o_idx],
+					    str_o_max_len - *str_o_idx);
+			if (len < 0)
+				len = -ENAMETOOLONG;
+		}
+		/* Valid character? */
+		if (len >= 0)
+			*str_o_idx += len;
+		else if (len == -ENAMETOOLONG) {
+			*needsCRC = 1;
+			gotch = 0;
+		} else {
+			str_o[(*str_o_idx)++] = ILLEGAL_CHAR_MARK;
+			*needsCRC = 1;
+		}
+	}
+	return gotch;
+}
+
+static int udf_name_from_CS0(struct super_block *sb,
+			     uint8_t *str_o, int str_max_len,
+			     const uint8_t *ocu, int ocu_len,
+			     int translate)
+{
+	uint32_t c;
+	uint8_t cmp_id;
+	int idx, len;
+	int u_ch;
+	int needsCRC = 0;
+	int ext_i_len, ext_max_len;
+	int str_o_len = 0;	/* Length of resulting output */
+	int ext_o_len = 0;	/* Extension output length */
+	int ext_crc_len = 0;	/* Extension output length if used with CRC */
+	int i_ext = -1;		/* Extension position in input buffer */
+	int o_crc = 0;		/* Rightmost possible output pos for CRC+ext */
+	unsigned short valueCRC;
+	uint8_t ext[EXT_SIZE * NLS_MAX_CHARSET_SIZE + 1];
+	uint8_t crc[CRC_LEN];
+	int (*conv_f)(wchar_t, unsigned char *, int);
+
+	if (str_max_len <= 0)
+		return 0;
+
+	if (ocu_len == 0) {
+		memset(str_o, 0, str_max_len);
+		return 0;
+	}
+
+	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
+		conv_f = UDF_SB(sb)->s_nls_map->uni2char;
+	else
+		conv_f = NULL;
+
+	cmp_id = ocu[0];
+	if (cmp_id != 8 && cmp_id != 16) {
+		memset(str_o, 0, str_max_len);
+		pr_err("unknown compression code (%u)\n", cmp_id);
+		return -EINVAL;
+	}
+	u_ch = cmp_id >> 3;
+
+	ocu++;
+	ocu_len--;
+
+	if (ocu_len % u_ch) {
+		pr_err("incorrect filename length (%d)\n", ocu_len + 1);
+		return -EINVAL;
+	}
+
+	if (translate) {
+		/* Look for extension */
+		for (idx = ocu_len - u_ch, ext_i_len = 0;
+		     (idx >= 0) && (ext_i_len < EXT_SIZE);
+		     idx -= u_ch, ext_i_len++) {
+			c = ocu[idx];
+			if (u_ch > 1)
+				c = (c << 8) | ocu[idx + 1];
+
+			if (c == EXT_MARK) {
+				if (ext_i_len)
+					i_ext = idx;
+				break;
+			}
+		}
+		if (i_ext >= 0) {
+			/* Convert extension */
+			ext_max_len = min_t(int, sizeof(ext), str_max_len);
+			ext[ext_o_len++] = EXT_MARK;
+			idx = i_ext + u_ch;
+			while (udf_name_conv_char(ext, ext_max_len, &ext_o_len,
+						  ocu, ocu_len, &idx,
+						  u_ch, &needsCRC,
+						  conv_f, translate)) {
+				if ((ext_o_len + CRC_LEN) < str_max_len)
+					ext_crc_len = ext_o_len;
+			}
+		}
+	}
+
+	idx = 0;
+	while (1) {
+		if (translate && (idx == i_ext)) {
+			if (str_o_len > (str_max_len - ext_o_len))
+				needsCRC = 1;
+			break;
+		}
+
+		if (!udf_name_conv_char(str_o, str_max_len, &str_o_len,
+					ocu, ocu_len, &idx,
+					u_ch, &needsCRC, conv_f, translate))
+			break;
+
+		if (translate &&
+		    (str_o_len <= (str_max_len - ext_o_len - CRC_LEN)))
+			o_crc = str_o_len;
+	}
+
+	if (translate) {
+		if (str_o_len <= 2 && str_o[0] == '.' &&
+		    (str_o_len == 1 || str_o[1] == '.'))
+			needsCRC = 1;
+		if (needsCRC) {
+			str_o_len = o_crc;
+			valueCRC = crc_itu_t(0, ocu, ocu_len);
+			crc[0] = CRC_MARK;
+			crc[1] = hex_asc_upper_hi(valueCRC >> 8);
+			crc[2] = hex_asc_upper_lo(valueCRC >> 8);
+			crc[3] = hex_asc_upper_hi(valueCRC);
+			crc[4] = hex_asc_upper_lo(valueCRC);
+			len = min_t(int, CRC_LEN, str_max_len - str_o_len);
+			memcpy(&str_o[str_o_len], crc, len);
+			str_o_len += len;
+			ext_o_len = ext_crc_len;
+		}
+		if (ext_o_len > 0) {
+			memcpy(&str_o[str_o_len], ext, ext_o_len);
+			str_o_len += ext_o_len;
+		}
+	}
+
+	return str_o_len;
+}
+
+static int udf_name_to_CS0(struct super_block *sb,
+			   uint8_t *ocu, int ocu_max_len,
+			   const uint8_t *str_i, int str_len)
+{
+	int i, len;
+	unsigned int max_val;
+	int u_len, u_ch;
+	unicode_t uni_char;
+	int (*conv_f)(const unsigned char *, int, wchar_t *);
+
+	if (ocu_max_len <= 0)
+		return 0;
+
+	if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
+		conv_f = UDF_SB(sb)->s_nls_map->char2uni;
+	else
+		conv_f = NULL;
+
+	memset(ocu, 0, ocu_max_len);
+	ocu[0] = 8;
+	max_val = 0xff;
+	u_ch = 1;
+
+try_again:
+	u_len = 1;
+	for (i = 0; i < str_len; i += len) {
+		/* Name didn't fit? */
+		if (u_len + u_ch > ocu_max_len)
+			return 0;
+		if (conv_f) {
+			wchar_t wchar;
+
+			len = conv_f(&str_i[i], str_len - i, &wchar);
+			if (len > 0)
+				uni_char = wchar;
+		} else {
+			len = utf8_to_utf32(&str_i[i], str_len - i,
+					    &uni_char);
+		}
+		/* Invalid character, deal with it */
+		if (len <= 0 || uni_char > UNICODE_MAX) {
+			len = 1;
+			uni_char = '?';
+		}
+
+		if (uni_char > max_val) {
+			unicode_t c;
+
+			if (max_val == 0xff) {
+				max_val = 0xffff;
+				ocu[0] = 0x10;
+				u_ch = 2;
+				goto try_again;
+			}
+			/*
+			 * Use UTF-16 encoding for chars outside we
+			 * cannot encode directly.
+			 */
+			if (u_len + 2 * u_ch > ocu_max_len)
+				return 0;
+
+			uni_char -= PLANE_SIZE;
+			c = SURROGATE_PAIR |
+			    ((uni_char >> SURROGATE_CHAR_BITS) &
+			     SURROGATE_CHAR_MASK);
+			ocu[u_len++] = (uint8_t)(c >> 8);
+			ocu[u_len++] = (uint8_t)(c & 0xff);
+			uni_char = SURROGATE_PAIR | SURROGATE_LOW |
+					(uni_char & SURROGATE_CHAR_MASK);
+		}
+
+		if (max_val == 0xffff)
+			ocu[u_len++] = (uint8_t)(uni_char >> 8);
+		ocu[u_len++] = (uint8_t)(uni_char & 0xff);
+	}
+
+	return u_len;
+}
+
+/*
+ * Convert CS0 dstring to output charset. Warning: This function may truncate
+ * input string if it is too long as it is used for informational strings only
+ * and it is better to truncate the string than to refuse mounting a media.
+ */
+int udf_dstrCS0toChar(struct super_block *sb, uint8_t *utf_o, int o_len,
+		      const uint8_t *ocu_i, int i_len)
+{
+	int s_len = 0;
+
+	if (i_len > 0) {
+		s_len = ocu_i[i_len - 1];
+		if (s_len >= i_len) {
+			pr_warn("incorrect dstring lengths (%d/%d),"
+				" truncating\n", s_len, i_len);
+			s_len = i_len - 1;
+			/* 2-byte encoding? Need to round properly... */
+			if (ocu_i[0] == 16)
+				s_len -= (s_len - 1) & 2;
+		}
+	}
+
+	return udf_name_from_CS0(sb, utf_o, o_len, ocu_i, s_len, 0);
+}
+
+int udf_get_filename(struct super_block *sb, const uint8_t *sname, int slen,
+		     uint8_t *dname, int dlen)
+{
+	int ret;
+
+	if (!slen)
+		return -EIO;
+
+	if (dlen <= 0)
+		return 0;
+
+	ret = udf_name_from_CS0(sb, dname, dlen, sname, slen, 1);
+	/* Zero length filename isn't valid... */
+	if (ret == 0)
+		ret = -EINVAL;
+	return ret;
+}
+
+int udf_put_filename(struct super_block *sb, const uint8_t *sname, int slen,
+		     uint8_t *dname, int dlen)
+{
+	return udf_name_to_CS0(sb, dname, dlen, sname, slen);
+}
+