[PATCH] arp: make arp_hdr_len() return unsigned int

[Alexey Dobriyan]

Negative ARP header length are not a thing.

Constify arguments while I'm at it.

Space savings:

        add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-3 (-3)
        function                        old     new   delta
        arpt_do_table                  1163    1160      -3

Signed-off-by: Alexey Dobriyan <adobri...@gmail.com>
---

 drivers/net/bonding/bond_main.c |    3 ++-
 include/linux/if_arp.h          |    2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -2491,7 +2491,8 @@ int bond_arp_rcv(const struct sk_buff *skb, struct 
bonding *bond,
        struct slave *curr_active_slave, *curr_arp_slave;
        unsigned char *arp_ptr;
        __be32 sip, tip;
-       int alen, is_arp = skb->protocol == __cpu_to_be16(ETH_P_ARP);
+       int is_arp = skb->protocol == __cpu_to_be16(ETH_P_ARP);
+       unsigned int alen;
 
        if (!slave_do_arp_validate(bond, slave)) {
                if ((slave_do_arp_validate_only(bond) && is_arp) ||
--- a/include/linux/if_arp.h
+++ b/include/linux/if_arp.h
@@ -31,7 +31,7 @@ static inline struct arphdr *arp_hdr(const struct sk_buff 
*skb)
        return (struct arphdr *)skb_network_header(skb);
 }
 
-static inline int arp_hdr_len(struct net_device *dev)
+static inline unsigned int arp_hdr_len(const struct net_device *dev)
 {
        switch (dev->type) {
 #if IS_ENABLED(CONFIG_FIREWIRE_NET)