bonding: Changed hashing function to just provide hash

Modified the hash function to return just hash separating from the
modulo operation that can be performed by the caller. This is to
make way for the tlb mode to use the same hashing policies that
are used in the 802.3ad and Xor mode.

Change-Id: I276609e87e0ca213c4d1b17b79c5e0b0f3d0dd6f
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_3ad.c

@@ -2440,7 +2440,7 @@ int bond_3ad_xmit_xor(struct sk_buff *skb, struct net_device *dev)
 		goto err_free;
 	}
 
-	slave_agg_no = bond_xmit_hash(bond, skb, slaves_in_agg);
+	slave_agg_no = bond_xmit_hash(bond, skb) % slaves_in_agg;
 	first_ok_slave = NULL;
 
 	bond_for_each_slave_rcu(bond, slave, iter) {

drivers/net/bonding/bond_main.c

@@ -3015,20 +3015,18 @@ static bool bond_flow_dissect(struct bonding *bond, struct sk_buff *skb,
  * bond_xmit_hash - generate a hash value based on the xmit policy
  * @bond: bonding device
  * @skb: buffer to use for headers
- * @count: modulo value
  *
  * This function will extract the necessary headers from the skb buffer and use
  * them to generate a hash based on the xmit_policy set in the bonding device
- * which will be reduced modulo count before returning.
  */
-int bond_xmit_hash(struct bonding *bond, struct sk_buff *skb, int count)
+u32 bond_xmit_hash(struct bonding *bond, struct sk_buff *skb)
 {
 	struct flow_keys flow;
 	u32 hash;
 
 	if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER2 ||
 	    !bond_flow_dissect(bond, skb, &flow))
-		return bond_eth_hash(skb) % count;
+		return bond_eth_hash(skb);
 
 	if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER23 ||
 	    bond->params.xmit_policy == BOND_XMIT_POLICY_ENCAP23)
@@ -3039,7 +3037,7 @@ int bond_xmit_hash(struct bonding *bond, struct sk_buff *skb, int count)
 	hash ^= (hash >> 16);
 	hash ^= (hash >> 8);
 
-	return hash % count;
+	return hash;
 }
 
 /*-------------------------- Device entry points ----------------------------*/
@@ -3666,7 +3664,7 @@ static int bond_xmit_xor(struct sk_buff *skb, struct net_device *bond_dev)
 {
 	struct bonding *bond = netdev_priv(bond_dev);
 
-	bond_xmit_slave_id(bond, skb, bond_xmit_hash(bond, skb, bond->slave_cnt));
+	bond_xmit_slave_id(bond, skb, bond_xmit_hash(bond, skb) % bond->slave_cnt);
 
 	return NETDEV_TX_OK;
 }

drivers/net/bonding/bonding.h

@@ -499,7 +499,7 @@ int bond_sysfs_slave_add(struct slave *slave);
 void bond_sysfs_slave_del(struct slave *slave);
 int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev);
 int bond_release(struct net_device *bond_dev, struct net_device *slave_dev);
-int bond_xmit_hash(struct bonding *bond, struct sk_buff *skb, int count);
+u32 bond_xmit_hash(struct bonding *bond, struct sk_buff *skb);
 void bond_select_active_slave(struct bonding *bond);
 void bond_change_active_slave(struct bonding *bond, struct slave *new_active);
 void bond_create_debugfs(void);