llc/snap: constify dev_addr passing

In preparation for netdev->dev_addr being constant
make all relevant arguments in LLC and SNAP constant.
Signed-off-by: NJakub Kicinski <kuba@kernel.org>

include/net/datalink.h

@@ -12,7 +12,7 @@ struct datalink_proto {
         int     (*rcvfunc)(struct sk_buff *, struct net_device *,
                                 struct packet_type *, struct net_device *);
 	int     (*request)(struct datalink_proto *, struct sk_buff *,
-                                        unsigned char *);
+			   const unsigned char *);
 	struct list_head node;
 };
 

include/net/llc.h

@@ -133,7 +133,7 @@ static inline void llc_sap_put(struct llc_sap *sap)
 struct llc_sap *llc_sap_find(unsigned char sap_value);
 
 int llc_build_and_send_ui_pkt(struct llc_sap *sap, struct sk_buff *skb,
-			      unsigned char *dmac, unsigned char dsap);
+			      const unsigned char *dmac, unsigned char dsap);
 
 void llc_sap_handler(struct llc_sap *sap, struct sk_buff *skb);
 void llc_conn_handler(struct llc_sap *sap, struct sk_buff *skb);

include/net/llc_if.h

@@ -62,7 +62,8 @@
 #define LLC_STATUS_CONFLICT	7 /* disconnect conn */
 #define LLC_STATUS_RESET_DONE	8 /*  */
 
-int llc_establish_connection(struct sock *sk, u8 *lmac, u8 *dmac, u8 dsap);
+int llc_establish_connection(struct sock *sk, const u8 *lmac, u8 *dmac,
+			     u8 dsap);
 int llc_build_and_send_pkt(struct sock *sk, struct sk_buff *skb);
 int llc_send_disc(struct sock *sk);
 #endif /* LLC_IF_H */

net/802/p8022.c

@@ -23,7 +23,7 @@
 #include <net/p8022.h>
 
 static int p8022_request(struct datalink_proto *dl, struct sk_buff *skb,
-			 unsigned char *dest)
+			 const unsigned char *dest)
 {
 	llc_build_and_send_ui_pkt(dl->sap, skb, dest, dl->sap->laddr.lsap);
 	return 0;

net/802/psnap.c

@@ -79,7 +79,7 @@ static int snap_rcv(struct sk_buff *skb, struct net_device *dev,
  *	Put a SNAP header on a frame and pass to 802.2
  */
 static int snap_request(struct datalink_proto *dl,
-			struct sk_buff *skb, u8 *dest)
+			struct sk_buff *skb, const u8 *dest)
 {
 	memcpy(skb_push(skb, 5), dl->type, 5);
 	llc_build_and_send_ui_pkt(snap_sap, skb, dest, snap_sap->laddr.lsap);

net/llc/llc_c_ac.c

@@ -781,7 +781,7 @@ int llc_conn_ac_send_sabme_cmd_p_set_x(struct sock *sk, struct sk_buff *skb)
 
 	if (nskb) {
 		struct llc_sap *sap = llc->sap;
-		u8 *dmac = llc->daddr.mac;
+		const u8 *dmac = llc->daddr.mac;
 
 		if (llc->dev->flags & IFF_LOOPBACK)
 			dmac = llc->dev->dev_addr;

net/llc/llc_if.c

@@ -80,7 +80,7 @@ int llc_build_and_send_pkt(struct sock *sk, struct sk_buff *skb)
  *	establishment will inform to upper layer via calling it's confirm
  *	function and passing proper information.
  */
-int llc_establish_connection(struct sock *sk, u8 *lmac, u8 *dmac, u8 dsap)
+int llc_establish_connection(struct sock *sk, const u8 *lmac, u8 *dmac, u8 dsap)
 {
 	int rc = -EISCONN;
 	struct llc_addr laddr, daddr;

net/llc/llc_output.c

@@ -56,7 +56,7 @@ int llc_mac_hdr_init(struct sk_buff *skb,
  *	package primitive as an event and send to SAP event handler
  */
 int llc_build_and_send_ui_pkt(struct llc_sap *sap, struct sk_buff *skb,
-			      unsigned char *dmac, unsigned char dsap)
+			      const unsigned char *dmac, unsigned char dsap)
 {
 	int rc;
 	llc_pdu_header_init(skb, LLC_PDU_TYPE_U, sap->laddr.lsap,

net/llc/llc_proc.c

@@ -26,7 +26,7 @@
 #include <net/llc_c_st.h>
 #include <net/llc_conn.h>
 
-static void llc_ui_format_mac(struct seq_file *seq, u8 *addr)
+static void llc_ui_format_mac(struct seq_file *seq, const u8 *addr)
 {
 	seq_printf(seq, "%pM", addr);
 }