Merge branch 'bridge-mrp-Extend-br_mrp_switchdev_'

Horatiu Vulturv says:

====================
bridge: mrp: Extend br_mrp_switchdev_*

This patch series extends MRP switchdev to allow the SW to have a better
understanding if the HW can implement the MRP functionality or it needs
to help the HW to run it. There are 3 cases:
- when HW can't implement at all the functionality.
- when HW can implement a part of the functionality but needs the SW
  implement the rest. For example if it can't detect when it stops
  receiving MRP Test frames but it can copy the MRP frames to CPU to
  allow the SW to determine this.  Another example is generating the MRP
  Test frames. If HW can't do that then the SW is used as backup.
- when HW can implement completely the functionality.

So, initially the SW tries to offload the entire functionality in HW, if
that fails it tries offload parts of the functionality in HW and use the
SW as helper and if also this fails then MRP can't run on this HW.

Based on these new calls, implement the switchdev for Ocelot driver. This
is an example where the HW can't run completely the functionality but it
can help the SW to run it, by trapping all MRP frames to CPU.

Also this patch series adds MRP support to DSA and implements the Felix
driver which just reuse the Ocelot functions. This part was just compiled
tested because I don't have any HW on which to do the actual tests.

v4:
 - remove ifdef MRP from include/net/switchdev.h
 - move MRP implementation for Ocelot in a different file such that
   Felix driver can use it.
 - extend DSA with MRP support
 - implement MRP support for Felix.
v3:
 - implement the switchdev calls needed by Ocelot driver.
v2:
 - fix typos in comments and in commit messages
 - remove some of the comments
 - move repeated code in helper function
 - fix issue when deleting a node when sw_backup was true
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 104 insertions, 67 deletions

diff --git a/net/bridge/br_mrp_switchdev.c b/net/bridge/br_mrp_switchdev.c
index 3c9a4abcf4eea..cb54b324fa8cc 100644
--- a/net/bridge/br_mrp_switchdev.c
+++ b/net/bridge/br_mrp_switchdev.c
@@ -4,6 +4,30 @@
 
 #include "br_private_mrp.h"
 
+static enum br_mrp_hw_support
+br_mrp_switchdev_port_obj(struct net_bridge *br,
+			  const struct switchdev_obj *obj, bool add)
+{
+	int err;
+
+	if (add)
+		err = switchdev_port_obj_add(br->dev, obj, NULL);
+	else
+		err = switchdev_port_obj_del(br->dev, obj);
+
+	/* In case of success just return and notify the SW that doesn't need
+	 * to do anything
+	 */
+	if (!err)
+		return BR_MRP_HW;
+
+	if (err != -EOPNOTSUPP)
+		return BR_MRP_NONE;
+
+	/* Continue with SW backup */
+	return BR_MRP_SW;
+}
+
 int br_mrp_switchdev_add(struct net_bridge *br, struct br_mrp *mrp)
 {
 	struct switchdev_obj_mrp mrp_obj = {
@@ -14,14 +38,11 @@ int br_mrp_switchdev_add(struct net_bridge *br, struct br_mrp *mrp)
 		.ring_id = mrp->ring_id,
 		.prio = mrp->prio,
 	};
-	int err;
 
-	err = switchdev_port_obj_add(br->dev, &mrp_obj.obj, NULL);
+	if (!IS_ENABLED(CONFIG_NET_SWITCHDEV))
+		return 0;
 
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
-	return 0;
+	return switchdev_port_obj_add(br->dev, &mrp_obj.obj, NULL);
 }
 
 int br_mrp_switchdev_del(struct net_bridge *br, struct br_mrp *mrp)
@@ -33,40 +54,54 @@ int br_mrp_switchdev_del(struct net_bridge *br, struct br_mrp *mrp)
 		.s_port = NULL,
 		.ring_id = mrp->ring_id,
 	};
-	int err;
-
-	err = switchdev_port_obj_del(br->dev, &mrp_obj.obj);
 
-	if (err && err != -EOPNOTSUPP)
-		return err;
+	if (!IS_ENABLED(CONFIG_NET_SWITCHDEV))
+		return 0;
 
-	return 0;
+	return switchdev_port_obj_del(br->dev, &mrp_obj.obj);
 }
 
-int br_mrp_switchdev_set_ring_role(struct net_bridge *br,
-				   struct br_mrp *mrp,
-				   enum br_mrp_ring_role_type role)
+enum br_mrp_hw_support
+br_mrp_switchdev_set_ring_role(struct net_bridge *br, struct br_mrp *mrp,
+			       enum br_mrp_ring_role_type role)
 {
 	struct switchdev_obj_ring_role_mrp mrp_role = {
 		.obj.orig_dev = br->dev,
 		.obj.id = SWITCHDEV_OBJ_ID_RING_ROLE_MRP,
 		.ring_role = role,
 		.ring_id = mrp->ring_id,
+		.sw_backup = false,
 	};
+	enum br_mrp_hw_support support;
 	int err;
 
-	if (role == BR_MRP_RING_ROLE_DISABLED)
-		err = switchdev_port_obj_del(br->dev, &mrp_role.obj);
-	else
+	if (!IS_ENABLED(CONFIG_NET_SWITCHDEV))
+		return BR_MRP_SW;
+
+	support = br_mrp_switchdev_port_obj(br, &mrp_role.obj,
+					    role != BR_MRP_RING_ROLE_DISABLED);
+	if (support != BR_MRP_SW)
+		return support;
+
+	/* If the driver can't configure to run completely the protocol in HW,
+	 * then try again to configure the HW so the SW can run the protocol.
+	 */
+	mrp_role.sw_backup = true;
+	if (role != BR_MRP_RING_ROLE_DISABLED)
 		err = switchdev_port_obj_add(br->dev, &mrp_role.obj, NULL);
+	else
+		err = switchdev_port_obj_del(br->dev, &mrp_role.obj);
 
-	return err;
+	if (!err)
+		return BR_MRP_SW;
+
+	return BR_MRP_NONE;
 }
 
-int br_mrp_switchdev_send_ring_test(struct net_bridge *br,
-				    struct br_mrp *mrp, u32 interval,
-				    u8 max_miss, u32 period,
-				    bool monitor)
+enum br_mrp_hw_support
+br_mrp_switchdev_send_ring_test(struct net_bridge *br, struct br_mrp *mrp,
+				u32 interval, u8 max_miss, u32 period,
+				bool monitor)
 {
 	struct switchdev_obj_ring_test_mrp test = {
 		.obj.orig_dev = br->dev,
@@ -77,14 +112,11 @@ int br_mrp_switchdev_send_ring_test(struct net_bridge *br,
 		.period = period,
 		.monitor = monitor,
 	};
-	int err;
 
-	if (interval == 0)
-		err = switchdev_port_obj_del(br->dev, &test.obj);
-	else
-		err = switchdev_port_obj_add(br->dev, &test.obj, NULL);
+	if (!IS_ENABLED(CONFIG_NET_SWITCHDEV))
+		return BR_MRP_SW;
 
-	return err;
+	return br_mrp_switchdev_port_obj(br, &test.obj, interval != 0);
 }
 
 int br_mrp_switchdev_set_ring_state(struct net_bridge *br,
@@ -97,19 +129,17 @@ int br_mrp_switchdev_set_ring_state(struct net_bridge *br,
 		.ring_state = state,
 		.ring_id = mrp->ring_id,
 	};
-	int err;
-
-	err = switchdev_port_obj_add(br->dev, &mrp_state.obj, NULL);
 
-	if (err && err != -EOPNOTSUPP)
-		return err;
+	if (!IS_ENABLED(CONFIG_NET_SWITCHDEV))
+		return 0;
 
-	return 0;
+	return switchdev_port_obj_add(br->dev, &mrp_state.obj, NULL);
 }
 
-int br_mrp_switchdev_set_in_role(struct net_bridge *br, struct br_mrp *mrp,
-				 u16 in_id, u32 ring_id,
-				 enum br_mrp_in_role_type role)
+enum br_mrp_hw_support
+br_mrp_switchdev_set_in_role(struct net_bridge *br, struct br_mrp *mrp,
+			     u16 in_id, u32 ring_id,
+			     enum br_mrp_in_role_type role)
 {
 	struct switchdev_obj_in_role_mrp mrp_role = {
 		.obj.orig_dev = br->dev,
@@ -118,15 +148,32 @@ int br_mrp_switchdev_set_in_role(struct net_bridge *br, struct br_mrp *mrp,
 		.in_id = mrp->in_id,
 		.ring_id = mrp->ring_id,
 		.i_port = rtnl_dereference(mrp->i_port)->dev,
+		.sw_backup = false,
 	};
+	enum br_mrp_hw_support support;
 	int err;
 
-	if (role == BR_MRP_IN_ROLE_DISABLED)
-		err = switchdev_port_obj_del(br->dev, &mrp_role.obj);
-	else
+	if (!IS_ENABLED(CONFIG_NET_SWITCHDEV))
+		return BR_MRP_SW;
+
+	support = br_mrp_switchdev_port_obj(br, &mrp_role.obj,
+					    role != BR_MRP_IN_ROLE_DISABLED);
+	if (support != BR_MRP_NONE)
+		return support;
+
+	/* If the driver can't configure to run completely the protocol in HW,
+	 * then try again to configure the HW so the SW can run the protocol.
+	 */
+	mrp_role.sw_backup = true;
+	if (role != BR_MRP_IN_ROLE_DISABLED)
 		err = switchdev_port_obj_add(br->dev, &mrp_role.obj, NULL);
+	else
+		err = switchdev_port_obj_del(br->dev, &mrp_role.obj);
+
+	if (!err)
+		return BR_MRP_SW;
 
-	return err;
+	return BR_MRP_NONE;
 }
 
 int br_mrp_switchdev_set_in_state(struct net_bridge *br, struct br_mrp *mrp,
@@ -138,18 +185,16 @@ int br_mrp_switchdev_set_in_state(struct net_bridge *br, struct br_mrp *mrp,
 		.in_state = state,
 		.in_id = mrp->in_id,
 	};
-	int err;
-
-	err = switchdev_port_obj_add(br->dev, &mrp_state.obj, NULL);
 
-	if (err && err != -EOPNOTSUPP)
-		return err;
+	if (!IS_ENABLED(CONFIG_NET_SWITCHDEV))
+		return 0;
 
-	return 0;
+	return switchdev_port_obj_add(br->dev, &mrp_state.obj, NULL);
 }
 
-int br_mrp_switchdev_send_in_test(struct net_bridge *br, struct br_mrp *mrp,
-				  u32 interval, u8 max_miss, u32 period)
+enum br_mrp_hw_support
+br_mrp_switchdev_send_in_test(struct net_bridge *br, struct br_mrp *mrp,
+			      u32 interval, u8 max_miss, u32 period)
 {
 	struct switchdev_obj_in_test_mrp test = {
 		.obj.orig_dev = br->dev,
@@ -159,14 +204,11 @@ int br_mrp_switchdev_send_in_test(struct net_bridge *br, struct br_mrp *mrp,
 		.in_id = mrp->in_id,
 		.period = period,
 	};
-	int err;
 
-	if (interval == 0)
-		err = switchdev_port_obj_del(br->dev, &test.obj);
-	else
-		err = switchdev_port_obj_add(br->dev, &test.obj, NULL);
+	if (!IS_ENABLED(CONFIG_NET_SWITCHDEV))
+		return BR_MRP_SW;
 
-	return err;
+	return br_mrp_switchdev_port_obj(br, &test.obj, interval != 0);
 }
 
 int br_mrp_port_switchdev_set_state(struct net_bridge_port *p, u32 state)
@@ -176,14 +218,11 @@ int br_mrp_port_switchdev_set_state(struct net_bridge_port *p, u32 state)
 		.id = SWITCHDEV_ATTR_ID_PORT_STP_STATE,
 		.u.stp_state = state,
 	};
-	int err;
 
-	err = switchdev_port_attr_set(p->dev, &attr, NULL);
-	if (err && err != -EOPNOTSUPP)
-		br_warn(p->br, "error setting offload MRP state on port %u(%s)\n",
-			(unsigned int)p->port_no, p->dev->name);
+	if (!IS_ENABLED(CONFIG_NET_SWITCHDEV))
+		return 0;
 
-	return err;
+	return switchdev_port_attr_set(p->dev, &attr, NULL);
 }
 
 int br_mrp_port_switchdev_set_role(struct net_bridge_port *p,
@@ -194,11 +233,9 @@ int br_mrp_port_switchdev_set_role(struct net_bridge_port *p,
 		.id = SWITCHDEV_ATTR_ID_MRP_PORT_ROLE,
 		.u.mrp_port_role = role,
 	};
-	int err;
 
-	err = switchdev_port_attr_set(p->dev, &attr, NULL);
-	if (err && err != -EOPNOTSUPP)
-		return err;
+	if (!IS_ENABLED(CONFIG_NET_SWITCHDEV))
+		return 0;
 
-	return 0;
+	return switchdev_port_attr_set(p->dev, &attr, NULL);
 }