net: sched: remove tcf_proto from ematch calls

This removes the tcf_proto argument from the ematch code paths that
only need it to reference the net namespace. This allows simplifying
qdisc code paths especially when we need to tear down the ematch
from an RCU callback. In this case we can not guarentee that the
tcf_proto structure is still valid.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_basic.c b/net/sched/cls_basic.c
index fe20826..90647a8 100644
--- a/net/sched/cls_basic.c
+++ b/net/sched/cls_basic.c
@@ -95,7 +95,7 @@
 
 	tcf_unbind_filter(tp, &f->res);
 	tcf_exts_destroy(&f->exts);
-	tcf_em_tree_destroy(tp, &f->ematches);
+	tcf_em_tree_destroy(&f->ematches);
 	kfree(f);
 }
 
diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c
index 3409f16..2f77a89 100644
--- a/net/sched/cls_cgroup.c
+++ b/net/sched/cls_cgroup.c
@@ -87,7 +87,7 @@
 						    rcu);
 
 	tcf_exts_destroy(&head->exts);
-	tcf_em_tree_destroy(head->tp, &head->ematches);
+	tcf_em_tree_destroy(&head->ematches);
 	kfree(head);
 }
 
@@ -157,7 +157,7 @@
 
 	if (head) {
 		tcf_exts_destroy(&head->exts);
-		tcf_em_tree_destroy(tp, &head->ematches);
+		tcf_em_tree_destroy(&head->ematches);
 		RCU_INIT_POINTER(tp->root, NULL);
 		kfree_rcu(head, rcu);
 	}
diff --git a/net/sched/cls_flow.c b/net/sched/cls_flow.c
index f18d27f7..a5d2b20 100644
--- a/net/sched/cls_flow.c
+++ b/net/sched/cls_flow.c
@@ -355,7 +355,7 @@
 
 	del_timer_sync(&f->perturb_timer);
 	tcf_exts_destroy(&f->exts);
-	tcf_em_tree_destroy(f->tp, &f->ematches);
+	tcf_em_tree_destroy(&f->ematches);
 	kfree(f);
 }
 
@@ -530,7 +530,7 @@
 	return 0;
 
 err2:
-	tcf_em_tree_destroy(tp, &t);
+	tcf_em_tree_destroy(&t);
 	kfree(fnew);
 err1:
 	tcf_exts_destroy(&e);
diff --git a/net/sched/em_canid.c b/net/sched/em_canid.c
index 7c292d4..ddd883c 100644
--- a/net/sched/em_canid.c
+++ b/net/sched/em_canid.c
@@ -120,7 +120,7 @@
 	return match;
 }
 
-static int em_canid_change(struct tcf_proto *tp, void *data, int len,
+static int em_canid_change(struct net *net, void *data, int len,
 			  struct tcf_ematch *m)
 {
 	struct can_filter *conf = data; /* Array with rules */
@@ -183,7 +183,7 @@
 	return 0;
 }
 
-static void em_canid_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
+static void em_canid_destroy(struct tcf_ematch *m)
 {
 	struct canid_match *cm = em_canid_priv(m);
 
diff --git a/net/sched/em_ipset.c b/net/sched/em_ipset.c
index 527aeb7..5b4a4ef 100644
--- a/net/sched/em_ipset.c
+++ b/net/sched/em_ipset.c
@@ -19,12 +19,11 @@
 #include <net/ip.h>
 #include <net/pkt_cls.h>
 
-static int em_ipset_change(struct tcf_proto *tp, void *data, int data_len,
+static int em_ipset_change(struct net *net, void *data, int data_len,
 			   struct tcf_ematch *em)
 {
 	struct xt_set_info *set = data;
 	ip_set_id_t index;
-	struct net *net = dev_net(qdisc_dev(tp->q));
 
 	if (data_len != sizeof(*set))
 		return -EINVAL;
@@ -42,11 +41,11 @@
 	return -ENOMEM;
 }
 
-static void em_ipset_destroy(struct tcf_proto *p, struct tcf_ematch *em)
+static void em_ipset_destroy(struct tcf_ematch *em)
 {
 	const struct xt_set_info *set = (const void *) em->data;
 	if (set) {
-		ip_set_nfnl_put(dev_net(qdisc_dev(p->q)), set->index);
+		ip_set_nfnl_put(em->net, set->index);
 		kfree((void *) em->data);
 	}
 }
diff --git a/net/sched/em_meta.c b/net/sched/em_meta.c
index 9b8c0b0..c8f8c39 100644
--- a/net/sched/em_meta.c
+++ b/net/sched/em_meta.c
@@ -856,7 +856,7 @@
 	[TCA_EM_META_HDR]	= { .len = sizeof(struct tcf_meta_hdr) },
 };
 
-static int em_meta_change(struct tcf_proto *tp, void *data, int len,
+static int em_meta_change(struct net *net, void *data, int len,
 			  struct tcf_ematch *m)
 {
 	int err;
@@ -908,7 +908,7 @@
 	return err;
 }
 
-static void em_meta_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
+static void em_meta_destroy(struct tcf_ematch *m)
 {
 	if (m)
 		meta_delete((struct meta_match *) m->data);
diff --git a/net/sched/em_nbyte.c b/net/sched/em_nbyte.c
index a3bed07..df3110d 100644
--- a/net/sched/em_nbyte.c
+++ b/net/sched/em_nbyte.c
@@ -23,7 +23,7 @@
 	char			pattern[0];
 };
 
-static int em_nbyte_change(struct tcf_proto *tp, void *data, int data_len,
+static int em_nbyte_change(struct net *net, void *data, int data_len,
 			   struct tcf_ematch *em)
 {
 	struct tcf_em_nbyte *nbyte = data;
diff --git a/net/sched/em_text.c b/net/sched/em_text.c
index 15d353d..f03c3de 100644
--- a/net/sched/em_text.c
+++ b/net/sched/em_text.c
@@ -45,7 +45,7 @@
 	return skb_find_text(skb, from, to, tm->config, &state) != UINT_MAX;
 }
 
-static int em_text_change(struct tcf_proto *tp, void *data, int len,
+static int em_text_change(struct net *net, void *data, int len,
 			  struct tcf_ematch *m)
 {
 	struct text_match *tm;
@@ -100,7 +100,7 @@
 	return 0;
 }
 
-static void em_text_destroy(struct tcf_proto *tp, struct tcf_ematch *m)
+static void em_text_destroy(struct tcf_ematch *m)
 {
 	if (EM_TEXT_PRIV(m) && EM_TEXT_PRIV(m)->config)
 		textsearch_destroy(EM_TEXT_PRIV(m)->config);
diff --git a/net/sched/ematch.c b/net/sched/ematch.c
index ad57f44..8250c36 100644
--- a/net/sched/ematch.c
+++ b/net/sched/ematch.c
@@ -178,6 +178,7 @@
 	struct tcf_ematch_hdr *em_hdr = nla_data(nla);
 	int data_len = nla_len(nla) - sizeof(*em_hdr);
 	void *data = (void *) em_hdr + sizeof(*em_hdr);
+	struct net *net = dev_net(qdisc_dev(tp->q));
 
 	if (!TCF_EM_REL_VALID(em_hdr->flags))
 		goto errout;
@@ -240,7 +241,7 @@
 			goto errout;
 
 		if (em->ops->change) {
-			err = em->ops->change(tp, data, data_len, em);
+			err = em->ops->change(net, data, data_len, em);
 			if (err < 0)
 				goto errout;
 		} else if (data_len > 0) {
@@ -271,6 +272,7 @@
 	em->matchid = em_hdr->matchid;
 	em->flags = em_hdr->flags;
 	em->datalen = data_len;
+	em->net = net;
 
 	err = 0;
 errout:
@@ -378,7 +380,7 @@
 	return err;
 
 errout_abort:
-	tcf_em_tree_destroy(tp, tree);
+	tcf_em_tree_destroy(tree);
 	return err;
 }
 EXPORT_SYMBOL(tcf_em_tree_validate);
@@ -393,7 +395,7 @@
  * tcf_em_tree_validate()/tcf_em_tree_change(). You must ensure that
  * the ematch tree is not in use before calling this function.
  */
-void tcf_em_tree_destroy(struct tcf_proto *tp, struct tcf_ematch_tree *tree)
+void tcf_em_tree_destroy(struct tcf_ematch_tree *tree)
 {
 	int i;
 
@@ -405,7 +407,7 @@
 
 		if (em->ops) {
 			if (em->ops->destroy)
-				em->ops->destroy(tp, em);
+				em->ops->destroy(em);
 			else if (!tcf_em_is_simple(em))
 				kfree((void *) em->data);
 			module_put(em->ops->owner);