batman-adv: Use common Jenkins Hash implementation

An unoptimized version of the Jenkins one-at-a-time hash function is used
and partially copied all over the code wherever an hashtable is used.
Instead the optimized version shared between the whole kernel should be
used to reduce code duplication and use better optimized code.

Only the DAT code must use the old implementation because it is used as
distributed hash function which has to be common for all nodes.

Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>

1 files changed, 15 insertions, 2 deletions

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c
index da1742d9059fd..2e6198ecc07d5 100644
--- a/net/batman-adv/distributed-arp-table.c
+++ b/net/batman-adv/distributed-arp-table.c
@@ -206,9 +206,22 @@ static uint32_t batadv_hash_dat(const void *data, uint32_t size)
 {
 	uint32_t hash = 0;
 	const struct batadv_dat_entry *dat = data;
+	const unsigned char *key;
+	uint32_t i;
+
+	key = (const unsigned char *)&dat->ip;
+	for (i = 0; i < sizeof(dat->ip); i++) {
+		hash += key[i];
+		hash += (hash << 10);
+		hash ^= (hash >> 6);
+	}
 
-	hash = batadv_hash_bytes(hash, &dat->ip, sizeof(dat->ip));
-	hash = batadv_hash_bytes(hash, &dat->vid, sizeof(dat->vid));
+	key = (const unsigned char *)&dat->vid;
+	for (i = 0; i < sizeof(dat->vid); i++) {
+		hash += key[i];
+		hash += (hash << 10);
+		hash ^= (hash >> 6);
+	}
 
 	hash += (hash << 3);
 	hash ^= (hash >> 11);