Merge branch 'get-rid-of-the-switchdev-transactional-model'

Vladimir Oltean says:

====================
Get rid of the switchdev transactional model

Changes in v4:
- Fixed build error in dsa_loop and build warning in hellcreek driver.
- Scheduling the mlxsw SPAN work item regardless of the VLAN add return
  code, as per Ido's and Petr's request.

Changes in v3:
- Resolved a build warning in mv88e6xxx and tested that it actually
  works properly, which resulted in an extra patch (02/11).
- Addressed Ido's minor feedback in commit 10/11 relating to a comment.

Changes in v2:
- Got rid of the vid_begin -> vid_end range too from the switchdev API.
- Actually propagating errors from DSA MDB and VLAN notifiers.

This series comes after the late realization that the prepare/commit
separation imposed by switchdev does not help literally anybody:
https://patchwork.kernel.org/project/netdevbpf/patch/20201212203901.351331-1-vladimir.oltean@nxp.com/

We should kill it before it inflicts even more damage to the error
handling logic in drivers.

Also remove the unused VLAN ranges feature from the switchdev VLAN
objects, which simplifies all drivers by quite a bit.
====================

Link: https://lore.kernel.org/r/20210109000156.1246735-1-olteanv@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 23 insertions, 56 deletions

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index f8b6a69b6873..5d7f6cada6a8 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -268,32 +268,29 @@ static int dsa_slave_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 }
 
 static int dsa_slave_port_attr_set(struct net_device *dev,
-				   const struct switchdev_attr *attr,
-				   struct switchdev_trans *trans)
+				   const struct switchdev_attr *attr)
 {
 	struct dsa_port *dp = dsa_slave_to_port(dev);
 	int ret;
 
 	switch (attr->id) {
 	case SWITCHDEV_ATTR_ID_PORT_STP_STATE:
-		ret = dsa_port_set_state(dp, attr->u.stp_state, trans);
+		ret = dsa_port_set_state(dp, attr->u.stp_state);
 		break;
 	case SWITCHDEV_ATTR_ID_BRIDGE_VLAN_FILTERING:
-		ret = dsa_port_vlan_filtering(dp, attr->u.vlan_filtering,
-					      trans);
+		ret = dsa_port_vlan_filtering(dp, attr->u.vlan_filtering);
 		break;
 	case SWITCHDEV_ATTR_ID_BRIDGE_AGEING_TIME:
-		ret = dsa_port_ageing_time(dp, attr->u.ageing_time, trans);
+		ret = dsa_port_ageing_time(dp, attr->u.ageing_time);
 		break;
 	case SWITCHDEV_ATTR_ID_PORT_PRE_BRIDGE_FLAGS:
-		ret = dsa_port_pre_bridge_flags(dp, attr->u.brport_flags,
-						trans);
+		ret = dsa_port_pre_bridge_flags(dp, attr->u.brport_flags);
 		break;
 	case SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS:
-		ret = dsa_port_bridge_flags(dp, attr->u.brport_flags, trans);
+		ret = dsa_port_bridge_flags(dp, attr->u.brport_flags);
 		break;
 	case SWITCHDEV_ATTR_ID_BRIDGE_MROUTER:
-		ret = dsa_port_mrouter(dp->cpu_dp, attr->u.mrouter, trans);
+		ret = dsa_port_mrouter(dp->cpu_dp, attr->u.mrouter);
 		break;
 	default:
 		ret = -EOPNOTSUPP;
@@ -318,7 +315,7 @@ dsa_slave_vlan_check_for_8021q_uppers(struct net_device *slave,
 			continue;
 
 		vid = vlan_dev_vlan_id(upper_dev);
-		if (vid >= vlan->vid_begin && vid <= vlan->vid_end)
+		if (vid == vlan->vid)
 			return -EBUSY;
 	}
 
@@ -326,13 +323,12 @@ dsa_slave_vlan_check_for_8021q_uppers(struct net_device *slave,
 }
 
 static int dsa_slave_vlan_add(struct net_device *dev,
-			      const struct switchdev_obj *obj,
-			      struct switchdev_trans *trans)
+			      const struct switchdev_obj *obj)
 {
 	struct net_device *master = dsa_slave_to_master(dev);
 	struct dsa_port *dp = dsa_slave_to_port(dev);
 	struct switchdev_obj_port_vlan vlan;
-	int vid, err;
+	int err;
 
 	if (obj->orig_dev != dev)
 		return -EOPNOTSUPP;
@@ -345,7 +341,7 @@ static int dsa_slave_vlan_add(struct net_device *dev,
 	/* Deny adding a bridge VLAN when there is already an 802.1Q upper with
 	 * the same VID.
 	 */
-	if (trans->ph_prepare && br_vlan_enabled(dp->bridge_dev)) {
+	if (br_vlan_enabled(dp->bridge_dev)) {
 		rcu_read_lock();
 		err = dsa_slave_vlan_check_for_8021q_uppers(dev, &vlan);
 		rcu_read_unlock();
@@ -353,7 +349,7 @@ static int dsa_slave_vlan_add(struct net_device *dev,
 			return err;
 	}
 
-	err = dsa_port_vlan_add(dp, &vlan, trans);
+	err = dsa_port_vlan_add(dp, &vlan);
 	if (err)
 		return err;
 
@@ -363,47 +359,34 @@ static int dsa_slave_vlan_add(struct net_device *dev,
 	 */
 	vlan.flags &= ~BRIDGE_VLAN_INFO_PVID;
 
-	err = dsa_port_vlan_add(dp->cpu_dp, &vlan, trans);
+	err = dsa_port_vlan_add(dp->cpu_dp, &vlan);
 	if (err)
 		return err;
 
-	for (vid = vlan.vid_begin; vid <= vlan.vid_end; vid++) {
-		err = vlan_vid_add(master, htons(ETH_P_8021Q), vid);
-		if (err)
-			return err;
-	}
-
-	return 0;
+	return vlan_vid_add(master, htons(ETH_P_8021Q), vlan.vid);
 }
 
 static int dsa_slave_port_obj_add(struct net_device *dev,
 				  const struct switchdev_obj *obj,
-				  struct switchdev_trans *trans,
 				  struct netlink_ext_ack *extack)
 {
 	struct dsa_port *dp = dsa_slave_to_port(dev);
 	int err;
 
-	/* For the prepare phase, ensure the full set of changes is feasable in
-	 * one go in order to signal a failure properly. If an operation is not
-	 * supported, return -EOPNOTSUPP.
-	 */
-
 	switch (obj->id) {
 	case SWITCHDEV_OBJ_ID_PORT_MDB:
 		if (obj->orig_dev != dev)
 			return -EOPNOTSUPP;
-		err = dsa_port_mdb_add(dp, SWITCHDEV_OBJ_PORT_MDB(obj), trans);
+		err = dsa_port_mdb_add(dp, SWITCHDEV_OBJ_PORT_MDB(obj));
 		break;
 	case SWITCHDEV_OBJ_ID_HOST_MDB:
 		/* DSA can directly translate this to a normal MDB add,
 		 * but on the CPU port.
 		 */
-		err = dsa_port_mdb_add(dp->cpu_dp, SWITCHDEV_OBJ_PORT_MDB(obj),
-				       trans);
+		err = dsa_port_mdb_add(dp->cpu_dp, SWITCHDEV_OBJ_PORT_MDB(obj));
 		break;
 	case SWITCHDEV_OBJ_ID_PORT_VLAN:
-		err = dsa_slave_vlan_add(dev, obj, trans);
+		err = dsa_slave_vlan_add(dev, obj);
 		break;
 	default:
 		err = -EOPNOTSUPP;
@@ -419,7 +402,7 @@ static int dsa_slave_vlan_del(struct net_device *dev,
 	struct net_device *master = dsa_slave_to_master(dev);
 	struct dsa_port *dp = dsa_slave_to_port(dev);
 	struct switchdev_obj_port_vlan *vlan;
-	int vid, err;
+	int err;
 
 	if (obj->orig_dev != dev)
 		return -EOPNOTSUPP;
@@ -436,8 +419,7 @@ static int dsa_slave_vlan_del(struct net_device *dev,
 	if (err)
 		return err;
 
-	for (vid = vlan->vid_begin; vid <= vlan->vid_end; vid++)
-		vlan_vid_del(master, htons(ETH_P_8021Q), vid);
+	vlan_vid_del(master, htons(ETH_P_8021Q), vlan->vid);
 
 	return 0;
 }
@@ -1289,33 +1271,19 @@ static int dsa_slave_vlan_rx_add_vid(struct net_device *dev, __be16 proto,
 	struct dsa_port *dp = dsa_slave_to_port(dev);
 	struct switchdev_obj_port_vlan vlan = {
 		.obj.id = SWITCHDEV_OBJ_ID_PORT_VLAN,
-		.vid_begin = vid,
-		.vid_end = vid,
+		.vid = vid,
 		/* This API only allows programming tagged, non-PVID VIDs */
 		.flags = 0,
 	};
-	struct switchdev_trans trans;
 	int ret;
 
 	/* User port... */
-	trans.ph_prepare = true;
-	ret = dsa_port_vlan_add(dp, &vlan, &trans);
-	if (ret)
-		return ret;
-
-	trans.ph_prepare = false;
-	ret = dsa_port_vlan_add(dp, &vlan, &trans);
+	ret = dsa_port_vlan_add(dp, &vlan);
 	if (ret)
 		return ret;
 
 	/* And CPU port... */
-	trans.ph_prepare = true;
-	ret = dsa_port_vlan_add(dp->cpu_dp, &vlan, &trans);
-	if (ret)
-		return ret;
-
-	trans.ph_prepare = false;
-	ret = dsa_port_vlan_add(dp->cpu_dp, &vlan, &trans);
+	ret = dsa_port_vlan_add(dp->cpu_dp, &vlan);
 	if (ret)
 		return ret;
 
@@ -1328,8 +1296,7 @@ static int dsa_slave_vlan_rx_kill_vid(struct net_device *dev, __be16 proto,
 	struct net_device *master = dsa_slave_to_master(dev);
 	struct dsa_port *dp = dsa_slave_to_port(dev);
 	struct switchdev_obj_port_vlan vlan = {
-		.vid_begin = vid,
-		.vid_end = vid,
+		.vid = vid,
 		/* This API only allows programming tagged, non-PVID VIDs */
 		.flags = 0,
 	};