netfilter: trivial code cleanup and doc changes

Changes while reading through the netfilter code.

Added hint about how conntrack nf_conn refcnt is accessed.
And renamed repl_hash to reply_hash for readability

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 7 insertions, 1 deletions

diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h
index b2ac6246b7e0..e10d1faa6d09 100644
--- a/include/net/netfilter/nf_conntrack.h
+++ b/include/net/netfilter/nf_conntrack.h
@@ -73,7 +73,13 @@ struct nf_conn_help {
 
 struct nf_conn {
         /* Usage count in here is 1 for hash table/destruct timer, 1 per skb,
-           plus 1 for any connection(s) we are `master' for */
+         * plus 1 for any connection(s) we are `master' for
+         *
+         * Hint, SKB address this struct and refcnt via skb->nfct and
+         * helpers nf_conntrack_get() and nf_conntrack_put().
+         * Helper nf_ct_put() equals nf_conntrack_put() by dec refcnt,
+         * beware nf_ct_get() is different and don't inc refcnt.
+         */
         struct nf_conntrack ct_general;
 
         spinlock_t lock;