[PATCH 1/2] decnet: dn_rtmsg: constify nf_hook_ops structures

From: Julia Lawall
Date: Sat Jul 29 2017 - 03:06:47 EST


The nf_hook_ops structure is only passed as the second argument to
nf_register_net_hook or nf_unregister_net_hook, both of which are
declared as const. Thus the nf_hook_ops structure itself can be
const.

Done with the help of Coccinelle.

// <smpl>
@r disable optional_qualifier@
identifier i;
position p;
@@
static struct nf_hook_ops i@p = { ... };

@ok1@
identifier r.i;
expression e;
position p;
@@
\(nf_register_net_hook\|nf_unregister_net_hook\)(e,&i@p)

@bad@
position p != {r.p,ok1.p};
identifier r.i;
struct nf_hook_ops e;
@@
e@i@p

@depends on !bad disable optional_qualifier@
identifier r.i;
@@
static
+const
struct nf_hook_ops i = { ... };
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@xxxxxxx>

---
net/decnet/netfilter/dn_rtmsg.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/decnet/netfilter/dn_rtmsg.c b/net/decnet/netfilter/dn_rtmsg.c
index aa8ffec..ab395e5 100644
--- a/net/decnet/netfilter/dn_rtmsg.c
+++ b/net/decnet/netfilter/dn_rtmsg.c
@@ -115,7 +115,7 @@ static inline void dnrmg_receive_user_skb(struct sk_buff *skb)
RCV_SKB_FAIL(-EINVAL);
}

-static struct nf_hook_ops dnrmg_ops __read_mostly = {
+static const struct nf_hook_ops dnrmg_ops = {
.hook = dnrmg_hook,
.pf = NFPROTO_DECNET,
.hooknum = NF_DN_ROUTE,