ext4: Add support for non-native signed/unsigned htree hash algorithms

The original ext3 hash algorithms assumed that variables of type char
were signed, as God and K&R intended.  Unfortunately, this assumption
is not true on some architectures.  Userspace support for marking
filesystems with non-native signed/unsigned chars was added two years
ago, but the kernel-side support was never added (until now).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 3 insertions, 0 deletions

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index b0537c827024..8370ffd2d62f 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -891,6 +891,9 @@ static inline __le16 ext4_rec_len_to_disk(unsigned len)
 #define DX_HASH_LEGACY          0
 #define DX_HASH_HALF_MD4        1
 #define DX_HASH_TEA             2
+#define DX_HASH_LEGACY_UNSIGNED 3
+#define DX_HASH_HALF_MD4_UNSIGNED       4
+#define DX_HASH_TEA_UNSIGNED            5
 
 #ifdef __KERNEL__