act_mirred: get rid of tcfm_ifindex from struct tcf_mirred

tcfm_dev always points to the correct netdev and we already
hold a refcnt, so no need to use tcfm_ifindex to lookup again.

If we would support moving target netdev across netns, using
pointer would be better than ifindex.

This also fixes dumping obsolete ifindex, now after the
target device is gone we just dump 0 as ifindex.

Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

11 files changed, 26 insertions, 41 deletions

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_tc.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_tc.c
index 0a5d72c8d04e..9807214da206 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_tc.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_tc.c
@@ -54,12 +54,10 @@ static int bnxt_tc_parse_redir(struct bnxt *bp,
 			       struct bnxt_tc_actions *actions,
 			       const struct tc_action *tc_act)
 {
-	int ifindex = tcf_mirred_ifindex(tc_act);
-	struct net_device *dev;
+	struct net_device *dev = tcf_mirred_dev(tc_act);
 
-	dev = __dev_get_by_index(dev_net(bp->dev), ifindex);
 	if (!dev) {
-		netdev_info(bp->dev, "no dev for ifindex=%d", ifindex);
+		netdev_info(bp->dev, "no dev in mirred action");
 		return -EINVAL;
 	}
 
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_flower.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_flower.c
index d4a548a6a55c..a12b894f135d 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_flower.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_flower.c
@@ -405,9 +405,7 @@ static void cxgb4_process_flow_actions(struct net_device *in,
 		} else if (is_tcf_gact_shot(a)) {
 			fs->action = FILTER_DROP;
 		} else if (is_tcf_mirred_egress_redirect(a)) {
-			int ifindex = tcf_mirred_ifindex(a);
-			struct net_device *out = __dev_get_by_index(dev_net(in),
-								    ifindex);
+			struct net_device *out = tcf_mirred_dev(a);
 			struct port_info *pi = netdev_priv(out);
 
 			fs->action = FILTER_SWITCH;
@@ -582,14 +580,14 @@ static int cxgb4_validate_flow_actions(struct net_device *dev,
 			/* Do nothing */
 		} else if (is_tcf_mirred_egress_redirect(a)) {
 			struct adapter *adap = netdev2adap(dev);
-			struct net_device *n_dev;
-			unsigned int i, ifindex;
+			struct net_device *n_dev, *target_dev;
+			unsigned int i;
 			bool found = false;
 
-			ifindex = tcf_mirred_ifindex(a);
+			target_dev = tcf_mirred_dev(a);
 			for_each_port(adap, i) {
 				n_dev = adap->port[i];
-				if (ifindex == n_dev->ifindex) {
+				if (target_dev == n_dev) {
 					found = true;
 					break;
 				}
diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c
index cd0cd13a964d..ab174bcfbfb0 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_tc_u32.c
@@ -114,14 +114,14 @@ static int fill_action_fields(struct adapter *adap,
 
 		/* Re-direct to specified port in hardware. */
 		if (is_tcf_mirred_egress_redirect(a)) {
-			struct net_device *n_dev;
-			unsigned int i, index;
+			struct net_device *n_dev, *target_dev;
 			bool found = false;
+			unsigned int i;
 
-			index = tcf_mirred_ifindex(a);
+			target_dev = tcf_mirred_dev(a);
 			for_each_port(adap, i) {
 				n_dev = adap->port[i];
-				if (index == n_dev->ifindex) {
+				if (target_dev == n_dev) {
 					fs->action = FILTER_SWITCH;
 					fs->eport = i;
 					found = true;
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 62a18914f00f..7737a05c717c 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -9101,9 +9101,11 @@ static int parse_tc_actions(struct ixgbe_adapter *adapter,
 
 		/* Redirect to a VF or a offloaded macvlan */
 		if (is_tcf_mirred_egress_redirect(a)) {
-			int ifindex = tcf_mirred_ifindex(a);
+			struct net_device *dev = tcf_mirred_dev(a);
 
-			err = handle_redirect_action(adapter, ifindex, queue,
+			if (!dev)
+				return -EINVAL;
+			err = handle_redirect_action(adapter, dev->ifindex, queue,
 						     action);
 			if (err == 0)
 				return err;
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
index 55979ec2e88a..3e03d2e8f96a 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_tc.c
@@ -1982,11 +1982,10 @@ static int parse_tc_fdb_actions(struct mlx5e_priv *priv, struct tcf_exts *exts,
 		}
 
 		if (is_tcf_mirred_egress_redirect(a)) {
-			int ifindex = tcf_mirred_ifindex(a);
 			struct net_device *out_dev;
 			struct mlx5e_priv *out_priv;
 
-			out_dev = __dev_get_by_index(dev_net(priv->netdev), ifindex);
+			out_dev = tcf_mirred_dev(a);
 
 			if (switchdev_port_same_parent_id(priv->netdev,
 							  out_dev)) {
@@ -1996,7 +1995,7 @@ static int parse_tc_fdb_actions(struct mlx5e_priv *priv, struct tcf_exts *exts,
 				rpriv = out_priv->ppriv;
 				attr->out_rep = rpriv->rep;
 			} else if (encap) {
-				parse_attr->mirred_ifindex = ifindex;
+				parse_attr->mirred_ifindex = out_dev->ifindex;
 				parse_attr->tun_info = *info;
 				attr->parse_attr = parse_attr;
 				attr->action |= MLX5_FLOW_CONTEXT_ACTION_ENCAP |
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index 2d0897b7d860..d2d945f2fc02 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -1571,14 +1571,11 @@ mlxsw_sp_port_add_cls_matchall_mirror(struct mlxsw_sp_port *mlxsw_sp_port,
 				      const struct tc_action *a,
 				      bool ingress)
 {
-	struct net *net = dev_net(mlxsw_sp_port->dev);
 	enum mlxsw_sp_span_type span_type;
 	struct mlxsw_sp_port *to_port;
 	struct net_device *to_dev;
-	int ifindex;
 
-	ifindex = tcf_mirred_ifindex(a);
-	to_dev = __dev_get_by_index(net, ifindex);
+	to_dev = tcf_mirred_dev(a);
 	if (!to_dev) {
 		netdev_err(mlxsw_sp_port->dev, "Could not find requested device\n");
 		return -EINVAL;
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
index 2f0e57857ea4..347e96461273 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
@@ -92,7 +92,6 @@ static int mlxsw_sp_flower_parse_actions(struct mlxsw_sp *mlxsw_sp,
 			if (err)
 				return err;
 		} else if (is_tcf_mirred_egress_redirect(a)) {
-			int ifindex = tcf_mirred_ifindex(a);
 			struct net_device *out_dev;
 			struct mlxsw_sp_fid *fid;
 			u16 fid_index;
@@ -104,7 +103,7 @@ static int mlxsw_sp_flower_parse_actions(struct mlxsw_sp *mlxsw_sp,
 			if (err)
 				return err;
 
-			out_dev = __dev_get_by_index(dev_net(dev), ifindex);
+			out_dev = tcf_mirred_dev(a);
 			if (out_dev == dev)
 				out_dev = NULL;
 
diff --git a/drivers/net/ethernet/netronome/nfp/flower/action.c b/drivers/net/ethernet/netronome/nfp/flower/action.c
index c1c595f8bb87..ca74c517f626 100644
--- a/drivers/net/ethernet/netronome/nfp/flower/action.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/action.c
@@ -93,13 +93,11 @@ nfp_fl_output(struct nfp_fl_output *output, const struct tc_action *action,
 	size_t act_size = sizeof(struct nfp_fl_output);
 	struct net_device *out_dev;
 	u16 tmp_flags;
-	int ifindex;
 
 	output->head.jump_id = NFP_FL_ACTION_OPCODE_OUTPUT;
 	output->head.len_lw = act_size >> NFP_FL_LW_SIZ;
 
-	ifindex = tcf_mirred_ifindex(action);
-	out_dev = __dev_get_by_index(dev_net(in_dev), ifindex);
+	out_dev = tcf_mirred_dev(action);
 	if (!out_dev)
 		return -EOPNOTSUPP;
 
diff --git a/include/net/tc_act/tc_mirred.h b/include/net/tc_act/tc_mirred.h
index 21d253c9a8c6..a2e9cbca5c9e 100644
--- a/include/net/tc_act/tc_mirred.h
+++ b/include/net/tc_act/tc_mirred.h
@@ -8,10 +8,8 @@
 struct tcf_mirred {
 	struct tc_action	common;
 	int			tcfm_eaction;
-	int			tcfm_ifindex;
 	bool			tcfm_mac_header_xmit;
 	struct net_device __rcu	*tcfm_dev;
-	struct net		*net;
 	struct list_head	tcfm_list;
 };
 #define to_mirred(a) ((struct tcf_mirred *)a)
@@ -34,9 +32,9 @@ static inline bool is_tcf_mirred_egress_mirror(const struct tc_action *a)
 	return false;
 }
 
-static inline int tcf_mirred_ifindex(const struct tc_action *a)
+static inline struct net_device *tcf_mirred_dev(const struct tc_action *a)
 {
-	return to_mirred(a)->tcfm_ifindex;
+	return rtnl_dereference(to_mirred(a)->tcfm_dev);
 }
 
 #endif /* __NET_TC_MIR_H */
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index d6e7a642493b..895db05d8c82 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -709,14 +709,12 @@ static int dsa_slave_add_cls_matchall(struct net_device *dev,
 	struct dsa_slave_priv *p = netdev_priv(dev);
 	struct dsa_mall_tc_entry *mall_tc_entry;
 	__be16 protocol = cls->common.protocol;
-	struct net *net = dev_net(dev);
 	struct dsa_switch *ds = dp->ds;
 	struct net_device *to_dev;
 	const struct tc_action *a;
 	struct dsa_port *to_dp;
 	int err = -EOPNOTSUPP;
 	LIST_HEAD(actions);
-	int ifindex;
 
 	if (!ds->ops->port_mirror_add)
 		return err;
@@ -730,8 +728,7 @@ static int dsa_slave_add_cls_matchall(struct net_device *dev,
 	if (is_tcf_mirred_egress_mirror(a) && protocol == htons(ETH_P_ALL)) {
 		struct dsa_mall_mirror_tc_entry *mirror;
 
-		ifindex = tcf_mirred_ifindex(a);
-		to_dev = __dev_get_by_index(net, ifindex);
+		to_dev = tcf_mirred_dev(a);
 		if (!to_dev)
 			return -EINVAL;
 
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 590f56afb985..ff497909c0ad 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -139,8 +139,6 @@ static int tcf_mirred_init(struct net *net, struct nlattr *nla,
 	m->tcf_action = parm->action;
 	m->tcfm_eaction = parm->eaction;
 	if (dev != NULL) {
-		m->tcfm_ifindex = parm->ifindex;
-		m->net = net;
 		if (ret != ACT_P_CREATED)
 			dev_put(rcu_dereference_protected(m->tcfm_dev, 1));
 		dev_hold(dev);
@@ -247,13 +245,14 @@ static int tcf_mirred_dump(struct sk_buff *skb, struct tc_action *a, int bind,
 {
 	unsigned char *b = skb_tail_pointer(skb);
 	struct tcf_mirred *m = to_mirred(a);
+	struct net_device *dev = rtnl_dereference(m->tcfm_dev);
 	struct tc_mirred opt = {
 		.index   = m->tcf_index,
 		.action  = m->tcf_action,
 		.refcnt  = m->tcf_refcnt - ref,
 		.bindcnt = m->tcf_bindcnt - bind,
 		.eaction = m->tcfm_eaction,
-		.ifindex = m->tcfm_ifindex,
+		.ifindex = dev ? dev->ifindex : 0,
 	};
 	struct tcf_t t;
 
@@ -318,7 +317,7 @@ static struct net_device *tcf_mirred_get_dev(const struct tc_action *a)
 {
 	struct tcf_mirred *m = to_mirred(a);
 
-	return __dev_get_by_index(m->net, m->tcfm_ifindex);
+	return rtnl_dereference(m->tcfm_dev);
 }
 
 static struct tc_action_ops act_mirred_ops = {