From dddf7da3985ee144b46ee287e81e47b9ee8bb980 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>

Date: Tue, 17 Mar 2020 23:25:52 +0100

Subject: [Backport dddf7da3985e] exfat: Simplify exfat_utf8_d_hash() for code

 points above U+FFFF

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Function partial_name_hash() takes long type value into which can be stored

one Unicode code point. Therefore conversion from UTF-32 to UTF-16 is not

needed.

Signed-off-by: Pali Rohár <pali@kernel.org>

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>

---

 src/namei.c | 10 ++--------

 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/src/namei.c b/src/namei.c

index 585b47b2db3da5d208fa1d53da9b18ae3d07c2dd..fa926b9c883adf353f3e911d96d6efcd71677dcc 100644

--- a/src/namei.c

+++ b/src/namei.c

@@ -147,16 +147,10 @@ static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr)

 			return charlen;

 		/*

-		 * Convert to UTF-16: code points above U+FFFF are encoded as

-		 * surrogate pairs.

 		 * exfat_toupper() works only for code points up to the U+FFFF.

 		 */

-		if (u > 0xFFFF) {

-			hash = partial_name_hash(exfat_high_surrogate(u), hash);

-			hash = partial_name_hash(exfat_low_surrogate(u), hash);

-		} else {

-			hash = partial_name_hash(exfat_toupper(sb, u), hash);

-		}

+		hash = partial_name_hash(u <= 0xFFFF ? exfat_toupper(sb, u) : u,

+					 hash);

 	}

 	qstr->hash = end_name_hash(hash);

-- 

2.31.1