net: constify skbuff and Qdisc elements

Preliminary patch before tcp constification

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 4fc88f3..2eb207e 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -46,14 +46,14 @@
 struct Qdisc {
 	int 			(*enqueue)(struct sk_buff *skb, struct Qdisc *dev);
 	struct sk_buff *	(*dequeue)(struct Qdisc *dev);
-	unsigned		flags;
+	unsigned int		flags;
 #define TCQ_F_BUILTIN		1
 #define TCQ_F_INGRESS		2
 #define TCQ_F_CAN_BYPASS	4
 #define TCQ_F_MQROOT		8
 #define TCQ_F_WARN_NONWC	(1 << 16)
 	int			padded;
-	struct Qdisc_ops	*ops;
+	const struct Qdisc_ops	*ops;
 	struct qdisc_size_table	__rcu *stab;
 	struct list_head	list;
 	u32			handle;
@@ -224,7 +224,7 @@
 	long			data[];
 };
 
-static inline int qdisc_qlen(struct Qdisc *q)
+static inline int qdisc_qlen(const struct Qdisc *q)
 {
 	return q->q.qlen;
 }
@@ -239,12 +239,12 @@
 	return &qdisc->q.lock;
 }
 
-static inline struct Qdisc *qdisc_root(struct Qdisc *qdisc)
+static inline struct Qdisc *qdisc_root(const struct Qdisc *qdisc)
 {
 	return qdisc->dev_queue->qdisc;
 }
 
-static inline struct Qdisc *qdisc_root_sleeping(struct Qdisc *qdisc)
+static inline struct Qdisc *qdisc_root_sleeping(const struct Qdisc *qdisc)
 {
 	return qdisc->dev_queue->qdisc_sleeping;
 }
@@ -260,7 +260,7 @@
  * root.  This is enforced by holding the RTNL semaphore, which
  * all users of this lock accessor must do.
  */
-static inline spinlock_t *qdisc_root_lock(struct Qdisc *qdisc)
+static inline spinlock_t *qdisc_root_lock(const struct Qdisc *qdisc)
 {
 	struct Qdisc *root = qdisc_root(qdisc);
 
@@ -268,7 +268,7 @@
 	return qdisc_lock(root);
 }
 
-static inline spinlock_t *qdisc_root_sleeping_lock(struct Qdisc *qdisc)
+static inline spinlock_t *qdisc_root_sleeping_lock(const struct Qdisc *qdisc)
 {
 	struct Qdisc *root = qdisc_root_sleeping(qdisc);
 
@@ -276,17 +276,17 @@
 	return qdisc_lock(root);
 }
 
-static inline struct net_device *qdisc_dev(struct Qdisc *qdisc)
+static inline struct net_device *qdisc_dev(const struct Qdisc *qdisc)
 {
 	return qdisc->dev_queue->dev;
 }
 
-static inline void sch_tree_lock(struct Qdisc *q)
+static inline void sch_tree_lock(const struct Qdisc *q)
 {
 	spin_lock_bh(qdisc_root_sleeping_lock(q));
 }
 
-static inline void sch_tree_unlock(struct Qdisc *q)
+static inline void sch_tree_unlock(const struct Qdisc *q)
 {
 	spin_unlock_bh(qdisc_root_sleeping_lock(q));
 }
@@ -319,7 +319,7 @@
 }
 
 static inline struct Qdisc_class_common *
-qdisc_class_find(struct Qdisc_class_hash *hash, u32 id)
+qdisc_class_find(const struct Qdisc_class_hash *hash, u32 id)
 {
 	struct Qdisc_class_common *cl;
 	struct hlist_node *n;
@@ -393,7 +393,7 @@
 }
 
 /* Are any of the TX qdiscs changing?  */
-static inline bool qdisc_tx_changing(struct net_device *dev)
+static inline bool qdisc_tx_changing(const struct net_device *dev)
 {
 	unsigned int i;
 	for (i = 0; i < dev->num_tx_queues; i++) {