[PATCH 1/4] exfat: Simplify exfat_utf8_d_hash() for code points above U+FFFF

From: Pali RohÃr
Date: Tue Mar 17 2020 - 18:26:29 EST


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 RohÃr <pali@xxxxxxxxxx>
---
fs/exfat/namei.c | 10 ++--------
1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/fs/exfat/namei.c b/fs/exfat/namei.c
index a8681d91f569..e0ec4ff366f5 100644
--- a/fs/exfat/namei.c
+++ b/fs/exfat/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);
--
2.20.1