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>

1 files changed, 9 insertions, 8 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 1ebf1ea29d60..3411f22e7d16 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -853,9 +853,9 @@ static inline struct sk_buff *skb_unshare(struct sk_buff *skb,
  *      The reference count is not incremented and the reference is therefore
  *      volatile. Use with caution.
  */
-static inline struct sk_buff *skb_peek(struct sk_buff_head *list_)
+static inline struct sk_buff *skb_peek(const struct sk_buff_head *list_)
 {
-        struct sk_buff *list = ((struct sk_buff *)list_)->next;
+        struct sk_buff *list = ((const struct sk_buff *)list_)->next;
         if (list == (struct sk_buff *)list_)
                 list = NULL;
         return list;
@@ -874,9 +874,9 @@ static inline struct sk_buff *skb_peek(struct sk_buff_head *list_)
  *      The reference count is not incremented and the reference is therefore
  *      volatile. Use with caution.
  */
-static inline struct sk_buff *skb_peek_tail(struct sk_buff_head *list_)
+static inline struct sk_buff *skb_peek_tail(const struct sk_buff_head *list_)
 {
-        struct sk_buff *list = ((struct sk_buff *)list_)->prev;
+        struct sk_buff *list = ((const struct sk_buff *)list_)->prev;
         if (list == (struct sk_buff *)list_)
                 list = NULL;
         return list;
@@ -1830,7 +1830,7 @@ static inline dma_addr_t skb_frag_dma_map(struct device *dev,
  *      Returns true if modifying the header part of the cloned buffer
  *      does not requires the data to be copied.
  */
-static inline int skb_clone_writable(struct sk_buff *skb, unsigned int len)
+static inline int skb_clone_writable(const struct sk_buff *skb, unsigned int len)
 {
         return !skb_header_cloned(skb) &&
                skb_headroom(skb) + len <= skb->hdr_len;
@@ -2451,7 +2451,8 @@ static inline bool skb_warn_if_lro(const struct sk_buff *skb)
 {
         /* LRO sets gso_size but not gso_type, whereas if GSO is really
          * wanted then gso_type will be set. */
-        struct skb_shared_info *shinfo = skb_shinfo(skb);
+        const struct skb_shared_info *shinfo = skb_shinfo(skb);
+
         if (skb_is_nonlinear(skb) && shinfo->gso_size != 0 &&
             unlikely(shinfo->gso_type == 0)) {
                 __skb_warn_lro_forwarding(skb);
@@ -2475,7 +2476,7 @@ static inline void skb_forward_csum(struct sk_buff *skb)
  * Instead of forcing ip_summed to CHECKSUM_NONE, we can
  * use this helper, to document places where we make this assertion.
  */
-static inline void skb_checksum_none_assert(struct sk_buff *skb)
+static inline void skb_checksum_none_assert(const struct sk_buff *skb)
 {
 #ifdef DEBUG
         BUG_ON(skb->ip_summed != CHECKSUM_NONE);
@@ -2484,7 +2485,7 @@ static inline void skb_checksum_none_assert(struct sk_buff *skb)
 
 bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off);
 
-static inline bool skb_is_recycleable(struct sk_buff *skb, int skb_size)
+static inline bool skb_is_recycleable(const struct sk_buff *skb, int skb_size)
 {
         if (irqs_disabled())
                 return false;