Linux Ethernet Bridging - Jul 2021 - [Bridge] [PATCH v6 net-next 0/7] Let switchdev drivers offload and unoffload bridge ports at their own convenience

This series introduces an explicit API through which switchdev drivers
mark a bridge port as offloaded or not:
- switchdev_bridge_port_offload()
- switchdev_bridge_port_unoffload()

Currently, the bridge assumes that a port is offloaded if
dev_get_port_parent_id(dev, &ppid, recurse=true) returns something, but
that is just an assumption that breaks some use cases (like a
non-offloaded LAG interface on top of a switchdev port, bridged with
other switchdev ports).

Along with some consolidation of the bridge logic to assign a "switchdev
offloading mark" to a port (now better called a "hardware
domain"), this
series allows the bridge driver side to no longer impose restrictions on
that configuration.

Right now, all switchdev drivers must be modified to use the explicit
API, but more and more logic can then be placed centrally in the bridge
and therefore ease the job of a switchdev driver writer in the future.

For example, the first thing we can hook into the explicit switchdev
offloading API calls are the switchdev object and FDB replay helpers.
So far, these have only been used by DSA in "pull" mode (where the
driver must ask for them). Adding the replay helpers to other drivers
involves a lot of repetition. But by moving the helpers inside the
bridge port offload/unoffload hook points, we can move the entire replay
process to "push" mode (where the bridge provides them automatically).

The explicit switchdev offloading API will see further extensions in the
future.

The patches were split from a larger series for easier review:
https://patchwork.kernel.org/project/netdevbpf/cover/20210718214434.3938850-1-vladimir.oltean
at nxp.com/

Changes in v6:
- Make the switchdev replay helpers opt-in
- Opt out of the replay helpers for mlxsw, rocker, prestera, sparx5,
  cpsw, am65-cpsw

Tobias Waldekranz (2):
  net: bridge: disambiguate offload_fwd_mark
  net: bridge: switchdev: recycle unused hwdoms

Vladimir Oltean (5):
  net: dpaa2-switch: use extack in dpaa2_switch_port_bridge_join
  net: dpaa2-switch: refactor prechangeupper sanity checks
  net: bridge: switchdev: let drivers inform which bridge ports are
    offloaded
  net: bridge: guard the switchdev replay helpers against a NULL
    notifier block
  net: bridge: move the switchdev object replay helpers to "push" mode

 .../ethernet/freescale/dpaa2/dpaa2-switch.c   |  67 ++++--
 .../ethernet/marvell/prestera/prestera_main.c |   3 +-
 .../marvell/prestera/prestera_switchdev.c     |  12 +-
 .../marvell/prestera/prestera_switchdev.h     |   3 +-
 .../mellanox/mlxsw/spectrum_switchdev.c       |  24 +-
 .../microchip/sparx5/sparx5_switchdev.c       |  24 +-
 drivers/net/ethernet/mscc/ocelot_net.c        | 104 ++++++--
 drivers/net/ethernet/rocker/rocker.h          |   3 +-
 drivers/net/ethernet/rocker/rocker_main.c     |   9 +-
 drivers/net/ethernet/rocker/rocker_ofdpa.c    |  19 +-
 drivers/net/ethernet/ti/am65-cpsw-nuss.c      |  18 +-
 drivers/net/ethernet/ti/cpsw_new.c            |  16 +-
 include/linux/if_bridge.h                     |  57 ++---
 net/bridge/br_fdb.c                           |   4 +-
 net/bridge/br_if.c                            |  11 +-
 net/bridge/br_mdb.c                           |   4 +-
 net/bridge/br_private.h                       |  60 ++++-
 net/bridge/br_switchdev.c                     | 227 +++++++++++++++---
 net/bridge/br_vlan.c                          |   4 +-
 net/dsa/dsa_priv.h                            |   6 +-
 net/dsa/port.c                                |  90 ++-----
 net/dsa/slave.c                               |  10 +-
 22 files changed, 560 insertions(+), 215 deletions(-)

-- 
2.25.1

We need to propagate the extack argument for
dpaa2_switch_port_bridge_join to use it in a future patch, and it looks
like there is already an error message there which is currently printed
to the console. Move it over netlink so it is properly transmitted to
user space.

Cc: Ioana Ciornei <ioana.ciornei at nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean at nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli at gmail.com>
Tested-by: Ioana Ciornei <ioana.ciornei at nxp.com>
Acked-by: Ioana Ciornei <ioana.ciornei at nxp.com>
---
v2->v3: patch is new
v3->v6: none

 drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
index f3d12d0714fb..62d322ebf1f2 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
@@ -1890,7 +1890,8 @@ static int dpaa2_switch_port_attr_set_event(struct
net_device *netdev,
 }
 
 static int dpaa2_switch_port_bridge_join(struct net_device *netdev,
-					 struct net_device *upper_dev)
+					 struct net_device *upper_dev,
+					 struct netlink_ext_ack *extack)
 {
 	struct ethsw_port_priv *port_priv = netdev_priv(netdev);
 	struct ethsw_core *ethsw = port_priv->ethsw_data;
@@ -1906,8 +1907,8 @@ static int dpaa2_switch_port_bridge_join(struct net_device
*netdev,
 
 		other_port_priv = netdev_priv(other_dev);
 		if (other_port_priv->ethsw_data != port_priv->ethsw_data) {
-			netdev_err(netdev,
-				   "Interface from a different DPSW is in the bridge
already!\n");
+			NL_SET_ERR_MSG_MOD(extack,
+					   "Interface from a different DPSW is in the bridge already");
 			return -EINVAL;
 		}
 	}
@@ -2067,7 +2068,9 @@ static int dpaa2_switch_port_netdevice_event(struct
notifier_block *nb,
 		upper_dev = info->upper_dev;
 		if (netif_is_bridge_master(upper_dev)) {
 			if (info->linking)
-				err = dpaa2_switch_port_bridge_join(netdev, upper_dev);
+				err = dpaa2_switch_port_bridge_join(netdev,
+								    upper_dev,
+								    extack);
 			else
 				err = dpaa2_switch_port_bridge_leave(netdev);
 		}
-- 
2.25.1

Make more room for some extra code in the NETDEV_PRECHANGEUPPER handler
by moving what already exists into a dedicated function.

Cc: Ioana Ciornei <ioana.ciornei at nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean at nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli at gmail.com>
Acked-by: Ioana Ciornei <ioana.ciornei at nxp.com>
---
v2->v3: patch is new
v3->v4: fix build error (s/dev/netdev/)
v4->v6: none

 .../ethernet/freescale/dpaa2/dpaa2-switch.c   | 37 +++++++++++++------
 1 file changed, 26 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
index 62d322ebf1f2..23798feb40b2 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
@@ -2030,6 +2030,28 @@ static int
dpaa2_switch_prevent_bridging_with_8021q_upper(struct net_device *net
 	return 0;
 }
 
+static int
+dpaa2_switch_prechangeupper_sanity_checks(struct net_device *netdev,
+					  struct net_device *upper_dev,
+					  struct netlink_ext_ack *extack)
+{
+	int err;
+
+	if (!br_vlan_enabled(upper_dev)) {
+		NL_SET_ERR_MSG_MOD(extack, "Cannot join a VLAN-unaware bridge");
+		return -EOPNOTSUPP;
+	}
+
+	err = dpaa2_switch_prevent_bridging_with_8021q_upper(netdev);
+	if (err) {
+		NL_SET_ERR_MSG_MOD(extack,
+				   "Cannot join a bridge while VLAN uppers are present");
+		return 0;
+	}
+
+	return 0;
+}
+
 static int dpaa2_switch_port_netdevice_event(struct notifier_block *nb,
 					     unsigned long event, void *ptr)
 {
@@ -2050,18 +2072,11 @@ static int dpaa2_switch_port_netdevice_event(struct
notifier_block *nb,
 		if (!netif_is_bridge_master(upper_dev))
 			break;
 
-		if (!br_vlan_enabled(upper_dev)) {
-			NL_SET_ERR_MSG_MOD(extack, "Cannot join a VLAN-unaware bridge");
-			err = -EOPNOTSUPP;
-			goto out;
-		}
-
-		err = dpaa2_switch_prevent_bridging_with_8021q_upper(netdev);
-		if (err) {
-			NL_SET_ERR_MSG_MOD(extack,
-					   "Cannot join a bridge while VLAN uppers are present");
+		err = dpaa2_switch_prechangeupper_sanity_checks(netdev,
+								upper_dev,
+								extack);
+		if (err)
 			goto out;
-		}
 
 		break;
 	case NETDEV_CHANGEUPPER:
-- 
2.25.1

From: Tobias Waldekranz <tobias at waldekranz.com>

Before this change, four related - but distinct - concepts where named
offload_fwd_mark:

- skb->offload_fwd_mark: Set by the switchdev driver if the underlying
  hardware has already forwarded this frame to the other ports in the
  same hardware domain.

- nbp->offload_fwd_mark: An idetifier used to group ports that share
  the same hardware forwarding domain.

- br->offload_fwd_mark: Counter used to make sure that unique IDs are
  used in cases where a bridge contains ports from multiple hardware
  domains.

- skb->cb->offload_fwd_mark: The hardware domain on which the frame
  ingressed and was forwarded.

Introduce the term "hardware forwarding domain" ("hwdom") in
the
bridge to denote a set of ports with the following property:

    If an skb with skb->offload_fwd_mark set, is received on a port
    belonging to hwdom N, that frame has already been forwarded to all
    other ports in hwdom N.

By decoupling the name from "offload_fwd_mark", we can extend the
term's definition in the future - e.g. to add constraints that
describe expected egress behavior - without overloading the meaning of
"offload_fwd_mark".

- nbp->offload_fwd_mark thus becomes nbp->hwdom.

- br->offload_fwd_mark becomes br->last_hwdom.

- skb->cb->offload_fwd_mark becomes skb->cb->src_hwdom. The slight
  change in naming here mandates a slight change in behavior of the
  nbp_switchdev_frame_mark() function. Previously, it only set this
  value in skb->cb for packets with skb->offload_fwd_mark true (ones
  which were forwarded in hardware). Whereas now we always track the
  incoming hwdom for all packets coming from a switchdev (even for the
  packets which weren't forwarded in hardware, such as STP BPDUs, IGMP
  reports etc). As all uses of skb->cb->offload_fwd_mark were already
  gated behind checks of skb->offload_fwd_mark, this will not introduce
  any functional change, but it paves the way for future changes where
  the ingressing hwdom must be known for frames coming from a switchdev
  regardless of whether they were forwarded in hardware or not
  (basically, if the skb comes from a switchdev, skb->cb->src_hwdom now
  always tracks which one).

  A typical example where this is relevant: the switchdev has a fixed
  configuration to trap STP BPDUs, but STP is not running on the bridge
  and the group_fwd_mask allows them to be forwarded. Say we have this
  setup:

        br0
       / | \
      /  |  \
  swp0 swp1 swp2

  A BPDU comes in on swp0 and is trapped to the CPU; the driver does not
  set skb->offload_fwd_mark. The bridge determines that the frame should
  be forwarded to swp{1,2}. It is imperative that forward offloading is
  _not_ allowed in this case, as the source hwdom is already
"poisoned".

  Recording the source hwdom allows this case to be handled properly.

v2->v3: added code comments
v3->v6: none

Signed-off-by: Tobias Waldekranz <tobias at waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean at nxp.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko at ti.com>
Reviewed-by: Florian Fainelli <f.fainelli at gmail.com>
---
 net/bridge/br_if.c        |  2 +-
 net/bridge/br_private.h   | 21 ++++++++++++++++-----
 net/bridge/br_switchdev.c | 16 ++++++++--------
 3 files changed, 25 insertions(+), 14 deletions(-)

diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
index 6e4a32354a13..838a277e3cf7 100644
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
@@ -643,7 +643,7 @@ int br_add_if(struct net_bridge *br, struct net_device *dev,
 	if (err)
 		goto err5;
 
-	err = nbp_switchdev_mark_set(p);
+	err = nbp_switchdev_hwdom_set(p);
 	if (err)
 		goto err6;
 
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 4681a4b6020f..4afba7da17ae 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -386,7 +386,10 @@ struct net_bridge_port {
 	struct netpoll			*np;
 #endif
 #ifdef CONFIG_NET_SWITCHDEV
-	int				offload_fwd_mark;
+	/* Identifier used to group ports that share the same switchdev
+	 * hardware domain.
+	 */
+	int				hwdom;
 #endif
 	u16				group_fwd_mask;
 	u16				backup_redirected_cnt;
@@ -510,7 +513,10 @@ struct net_bridge {
 	u32				auto_cnt;
 
 #ifdef CONFIG_NET_SWITCHDEV
-	int offload_fwd_mark;
+	/* Counter used to make sure that hardware domains get unique
+	 * identifiers in case a bridge spans multiple switchdev instances.
+	 */
+	int				last_hwdom;
 #endif
 	struct hlist_head		fdb_list;
 
@@ -540,7 +546,12 @@ struct br_input_skb_cb {
 #endif
 
 #ifdef CONFIG_NET_SWITCHDEV
-	int offload_fwd_mark;
+	/* The switchdev hardware domain from which this packet was received.
+	 * If skb->offload_fwd_mark was set, then this packet was already
+	 * forwarded by hardware to the other ports in the source hardware
+	 * domain, otherwise it wasn't.
+	 */
+	int src_hwdom;
 #endif
 };
 
@@ -1828,7 +1839,7 @@ static inline void br_sysfs_delbr(struct net_device *dev)
{ return; }
 
 /* br_switchdev.c */
 #ifdef CONFIG_NET_SWITCHDEV
-int nbp_switchdev_mark_set(struct net_bridge_port *p);
+int nbp_switchdev_hwdom_set(struct net_bridge_port *p);
 void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
 			      struct sk_buff *skb);
 bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
@@ -1848,7 +1859,7 @@ static inline void br_switchdev_frame_unmark(struct
sk_buff *skb)
 	skb->offload_fwd_mark = 0;
 }
 #else
-static inline int nbp_switchdev_mark_set(struct net_bridge_port *p)
+static inline int nbp_switchdev_hwdom_set(struct net_bridge_port *p)
 {
 	return 0;
 }
diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
index d3adee0f91f9..833fd30482c2 100644
--- a/net/bridge/br_switchdev.c
+++ b/net/bridge/br_switchdev.c
@@ -8,20 +8,20 @@
 
 #include "br_private.h"
 
-static int br_switchdev_mark_get(struct net_bridge *br, struct net_device *dev)
+static int br_switchdev_hwdom_get(struct net_bridge *br, struct net_device
*dev)
 {
 	struct net_bridge_port *p;
 
 	/* dev is yet to be added to the port list. */
 	list_for_each_entry(p, &br->port_list, list) {
 		if (netdev_port_same_parent_id(dev, p->dev))
-			return p->offload_fwd_mark;
+			return p->hwdom;
 	}
 
-	return ++br->offload_fwd_mark;
+	return ++br->last_hwdom;
 }
 
-int nbp_switchdev_mark_set(struct net_bridge_port *p)
+int nbp_switchdev_hwdom_set(struct net_bridge_port *p)
 {
 	struct netdev_phys_item_id ppid = { };
 	int err;
@@ -35,7 +35,7 @@ int nbp_switchdev_mark_set(struct net_bridge_port *p)
 		return err;
 	}
 
-	p->offload_fwd_mark = br_switchdev_mark_get(p->br, p->dev);
+	p->hwdom = br_switchdev_hwdom_get(p->br, p->dev);
 
 	return 0;
 }
@@ -43,15 +43,15 @@ int nbp_switchdev_mark_set(struct net_bridge_port *p)
 void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
 			      struct sk_buff *skb)
 {
-	if (skb->offload_fwd_mark &&
!WARN_ON_ONCE(!p->offload_fwd_mark))
-		BR_INPUT_SKB_CB(skb)->offload_fwd_mark = p->offload_fwd_mark;
+	if (p->hwdom)
+		BR_INPUT_SKB_CB(skb)->src_hwdom = p->hwdom;
 }
 
 bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
 				  const struct sk_buff *skb)
 {
 	return !skb->offload_fwd_mark ||
-	       BR_INPUT_SKB_CB(skb)->offload_fwd_mark != p->offload_fwd_mark;
+	       BR_INPUT_SKB_CB(skb)->src_hwdom != p->hwdom;
 }
 
 /* Flags that can be offloaded to hardware */
-- 
2.25.1

From: Tobias Waldekranz <tobias at waldekranz.com>

Since hwdoms have only been used thus far for equality comparisons, the
bridge has used the simplest possible assignment policy; using a
counter to keep track of the last value handed out.

With the upcoming transmit offloading, we need to perform set
operations efficiently based on hwdoms, e.g. we want to answer
questions like "has this skb been forwarded to any port within this
hwdom?"

Move to a bitmap-based allocation scheme that recycles hwdoms once all
members leaves the bridge. This means that we can use a single
unsigned long to keep track of the hwdoms that have received an skb.

v1->v2: convert the typedef DECLARE_BITMAP(br_hwdom_map_t, BR_HWDOM_MAX)
        into a plain unsigned long.
v2->v6: none

Signed-off-by: Tobias Waldekranz <tobias at waldekranz.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean at nxp.com>
---
 net/bridge/br_if.c        |  4 +-
 net/bridge/br_private.h   | 27 ++++++++---
 net/bridge/br_switchdev.c | 94 ++++++++++++++++++++++++++-------------
 3 files changed, 86 insertions(+), 39 deletions(-)

diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
index 838a277e3cf7..c0df50e4abbb 100644
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
@@ -349,6 +349,7 @@ static void del_nbp(struct net_bridge_port *p)
 	nbp_backup_clear(p);
 
 	nbp_update_port_count(br);
+	nbp_switchdev_del(p);
 
 	netdev_upper_dev_unlink(dev, br->dev);
 
@@ -643,7 +644,7 @@ int br_add_if(struct net_bridge *br, struct net_device *dev,
 	if (err)
 		goto err5;
 
-	err = nbp_switchdev_hwdom_set(p);
+	err = nbp_switchdev_add(p);
 	if (err)
 		goto err6;
 
@@ -719,6 +720,7 @@ int br_add_if(struct net_bridge *br, struct net_device *dev,
 	list_del_rcu(&p->list);
 	br_fdb_delete_by_port(br, p, 0, 1);
 	nbp_update_port_count(br);
+	nbp_switchdev_del(p);
 err6:
 	netdev_upper_dev_unlink(dev, br->dev);
 err5:
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 4afba7da17ae..1c1732d7212a 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -29,6 +29,8 @@
 
 #define BR_MULTICAST_DEFAULT_HASH_MAX 4096
 
+#define BR_HWDOM_MAX BITS_PER_LONG
+
 #define BR_VERSION	"2.3"
 
 /* Control of forwarding link local multicast */
@@ -517,6 +519,8 @@ struct net_bridge {
 	 * identifiers in case a bridge spans multiple switchdev instances.
 	 */
 	int				last_hwdom;
+	/* Bit mask of hardware domain numbers in use */
+	unsigned long			busy_hwdoms;
 #endif
 	struct hlist_head		fdb_list;
 
@@ -1839,7 +1843,6 @@ static inline void br_sysfs_delbr(struct net_device *dev)
{ return; }
 
 /* br_switchdev.c */
 #ifdef CONFIG_NET_SWITCHDEV
-int nbp_switchdev_hwdom_set(struct net_bridge_port *p);
 void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
 			      struct sk_buff *skb);
 bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
@@ -1853,17 +1856,15 @@ void br_switchdev_fdb_notify(struct net_bridge *br,
 int br_switchdev_port_vlan_add(struct net_device *dev, u16 vid, u16 flags,
 			       struct netlink_ext_ack *extack);
 int br_switchdev_port_vlan_del(struct net_device *dev, u16 vid);
+int nbp_switchdev_add(struct net_bridge_port *p);
+void nbp_switchdev_del(struct net_bridge_port *p);
+void br_switchdev_init(struct net_bridge *br);
 
 static inline void br_switchdev_frame_unmark(struct sk_buff *skb)
 {
 	skb->offload_fwd_mark = 0;
 }
 #else
-static inline int nbp_switchdev_hwdom_set(struct net_bridge_port *p)
-{
-	return 0;
-}
-
 static inline void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
 					    struct sk_buff *skb)
 {
@@ -1904,6 +1905,20 @@ br_switchdev_fdb_notify(struct net_bridge *br,
 static inline void br_switchdev_frame_unmark(struct sk_buff *skb)
 {
 }
+
+static inline int nbp_switchdev_add(struct net_bridge_port *p)
+{
+	return 0;
+}
+
+static inline void nbp_switchdev_del(struct net_bridge_port *p)
+{
+}
+
+static inline void br_switchdev_init(struct net_bridge *br)
+{
+}
+
 #endif /* CONFIG_NET_SWITCHDEV */
 
 /* br_arp_nd_proxy.c */
diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
index 833fd30482c2..f3120f13c293 100644
--- a/net/bridge/br_switchdev.c
+++ b/net/bridge/br_switchdev.c
@@ -8,38 +8,6 @@
 
 #include "br_private.h"
 
-static int br_switchdev_hwdom_get(struct net_bridge *br, struct net_device
*dev)
-{
-	struct net_bridge_port *p;
-
-	/* dev is yet to be added to the port list. */
-	list_for_each_entry(p, &br->port_list, list) {
-		if (netdev_port_same_parent_id(dev, p->dev))
-			return p->hwdom;
-	}
-
-	return ++br->last_hwdom;
-}
-
-int nbp_switchdev_hwdom_set(struct net_bridge_port *p)
-{
-	struct netdev_phys_item_id ppid = { };
-	int err;
-
-	ASSERT_RTNL();
-
-	err = dev_get_port_parent_id(p->dev, &ppid, true);
-	if (err) {
-		if (err == -EOPNOTSUPP)
-			return 0;
-		return err;
-	}
-
-	p->hwdom = br_switchdev_hwdom_get(p->br, p->dev);
-
-	return 0;
-}
-
 void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
 			      struct sk_buff *skb)
 {
@@ -156,3 +124,65 @@ int br_switchdev_port_vlan_del(struct net_device *dev, u16
vid)
 
 	return switchdev_port_obj_del(dev, &v.obj);
 }
+
+static int nbp_switchdev_hwdom_set(struct net_bridge_port *joining)
+{
+	struct net_bridge *br = joining->br;
+	struct net_bridge_port *p;
+	int hwdom;
+
+	/* joining is yet to be added to the port list. */
+	list_for_each_entry(p, &br->port_list, list) {
+		if (netdev_port_same_parent_id(joining->dev, p->dev)) {
+			joining->hwdom = p->hwdom;
+			return 0;
+		}
+	}
+
+	hwdom = find_next_zero_bit(&br->busy_hwdoms, BR_HWDOM_MAX, 1);
+	if (hwdom >= BR_HWDOM_MAX)
+		return -EBUSY;
+
+	set_bit(hwdom, &br->busy_hwdoms);
+	joining->hwdom = hwdom;
+	return 0;
+}
+
+static void nbp_switchdev_hwdom_put(struct net_bridge_port *leaving)
+{
+	struct net_bridge *br = leaving->br;
+	struct net_bridge_port *p;
+
+	/* leaving is no longer in the port list. */
+	list_for_each_entry(p, &br->port_list, list) {
+		if (p->hwdom == leaving->hwdom)
+			return;
+	}
+
+	clear_bit(leaving->hwdom, &br->busy_hwdoms);
+}
+
+int nbp_switchdev_add(struct net_bridge_port *p)
+{
+	struct netdev_phys_item_id ppid = { };
+	int err;
+
+	ASSERT_RTNL();
+
+	err = dev_get_port_parent_id(p->dev, &ppid, true);
+	if (err) {
+		if (err == -EOPNOTSUPP)
+			return 0;
+		return err;
+	}
+
+	return nbp_switchdev_hwdom_set(p);
+}
+
+void nbp_switchdev_del(struct net_bridge_port *p)
+{
+	ASSERT_RTNL();
+
+	if (p->hwdom)
+		nbp_switchdev_hwdom_put(p);
+}
-- 
2.25.1

On reception of an skb, the bridge checks if it was marked as 'already
forwarded in hardware' (checks if skb->offload_fwd_mark == 1), and if it
is, it assigns the source hardware domain of that skb based on the
hardware domain of the ingress port. Then during forwarding, it enforces
that the egress port must have a different hardware domain than the
ingress one (this is done in nbp_switchdev_allowed_egress).

Non-switchdev drivers don't report any physical switch id (neither
through devlink nor .ndo_get_port_parent_id), therefore the bridge
assigns them a hardware domain of 0, and packets coming from them will
always have skb->offload_fwd_mark = 0. So there aren't any restrictions.

Problems appear due to the fact that DSA would like to perform software
fallback for bonding and team interfaces that the physical switch cannot
offload.

       +-- br0 ---+
      / /   |      \
     / /    |       \
    /  |    |      bond0
   /   |    |     /    \
 swp0 swp1 swp2 swp3 swp4

There, it is desirable that the presence of swp3 and swp4 under a
non-offloaded LAG does not preclude us from doing hardware bridging
beteen swp0, swp1 and swp2. The bandwidth of the CPU is often times high
enough that software bridging between {swp0,swp1,swp2} and bond0 is not
impractical.

But this creates an impossible paradox given the current way in which
port hardware domains are assigned. When the driver receives a packet
from swp0 (say, due to flooding), it must set skb->offload_fwd_mark to
something.

- If we set it to 0, then the bridge will forward it towards swp1, swp2
  and bond0. But the switch has already forwarded it towards swp1 and
  swp2 (not to bond0, remember, that isn't offloaded, so as far as the
  switch is concerned, ports swp3 and swp4 are not looking up the FDB,
  and the entire bond0 is a destination that is strictly behind the
  CPU). But we don't want duplicated traffic towards swp1 and swp2, so
  it's not ok to set skb->offload_fwd_mark = 0.

- If we set it to 1, then the bridge will not forward the skb towards
  the ports with the same switchdev mark, i.e. not to swp1, swp2 and
  bond0. Towards swp1 and swp2 that's ok, but towards bond0? It should
  have forwarded the skb there.

So the real issue is that bond0 will be assigned the same hardware
domain as {swp0,swp1,swp2}, because the function that assigns hardware
domains to bridge ports, nbp_switchdev_add(), recurses through bond0's
lower interfaces until it finds something that implements devlink (calls
dev_get_port_parent_id with bool recurse = true). This is a problem
because the fact that bond0 can be offloaded by swp3 and swp4 in our
example is merely an assumption.

A solution is to give the bridge explicit hints as to what hardware
domain it should use for each port.

Currently, the bridging offload is very 'silent': a driver registers a
netdevice notifier, which is put on the netns's notifier chain, and
which sniffs around for NETDEV_CHANGEUPPER events where the upper is a
bridge, and the lower is an interface it knows about (one registered by
this driver, normally). Then, from within that notifier, it does a bunch
of stuff behind the bridge's back, without the bridge necessarily
knowing that there's somebody offloading that port. It looks like this:

     ip link set swp0 master br0
                  |
                  v
 br_add_if() calls netdev_master_upper_dev_link()
                  |
                  v
        call_netdevice_notifiers
                  |
                  v
       dsa_slave_netdevice_event
                  |
                  v
        oh, hey! it's for me!
                  |
                  v
           .port_bridge_join

What we do to solve the conundrum is to be less silent, and change the
switchdev drivers to present themselves to the bridge. Something like this:

     ip link set swp0 master br0
                  |
                  v
 br_add_if() calls netdev_master_upper_dev_link()
                  |
                  v                    bridge: Aye! I'll use this
        call_netdevice_notifiers           ^  ppid as the
                  |                        |  hardware domain for
                  v                        |  this port, and zero
       dsa_slave_netdevice_event           |  if I got nothing.
                  |                        |
                  v                        |
        oh, hey! it's for me!              |
                  |                        |
                  v                        |
           .port_bridge_join               |
                  |                        |
                  +------------------------+
             switchdev_bridge_port_offload(swp0, swp0)

Then stacked interfaces (like bond0 on top of swp3/swp4) would be
treated differently in DSA, depending on whether we can or cannot
offload them.

The offload case:

    ip link set bond0 master br0
                  |
                  v
 br_add_if() calls netdev_master_upper_dev_link()
                  |
                  v                    bridge: Aye! I'll use this
        call_netdevice_notifiers           ^  ppid as the
                  |                        |  switchdev mark for
                  v                        |        bond0.
       dsa_slave_netdevice_event           | Coincidentally (or not),
                  |                        | bond0 and swp0, swp1, swp2
                  v                        | all have the same switchdev
        hmm, it's not quite for me,        | mark now, since the ASIC
         but my driver has already         | is able to forward towards
           called .port_lag_join           | all these ports in hw.
          for it, because I have           |
      a port with dp->lag_dev == bond0.    |
                  |                        |
                  v                        |
           .port_bridge_join               |
           for swp3 and swp4               |
                  |                        |
                  +------------------------+
            switchdev_bridge_port_offload(bond0, swp3)
            switchdev_bridge_port_offload(bond0, swp4)

And the non-offload case:

    ip link set bond0 master br0
                  |
                  v
 br_add_if() calls netdev_master_upper_dev_link()
                  |
                  v                    bridge waiting:
        call_netdevice_notifiers           ^  huh, switchdev_bridge_port_offload
                  |                        |  wasn't called, okay, I'll
use a
                  v                        |  hwdom of zero for this one.
       dsa_slave_netdevice_event           :  Then packets received on swp0 will
                  |                        :  not be software-forwarded towards
                  v                        :  swp1, but they will towards bond0.
         it's not for me, but
       bond0 is an upper of swp3
      and swp4, but their dp->lag_dev
       is NULL because they couldn't
            offload it.

Basically we can draw the conclusion that the lowers of a bridge port
can come and go, so depending on the configuration of lowers for a
bridge port, it can dynamically toggle between offloaded and unoffloaded.
Therefore, we need an equivalent switchdev_bridge_port_unoffload too.

This patch changes the way any switchdev driver interacts with the
bridge. From now on, everybody needs to call switchdev_bridge_port_offload
and switchdev_bridge_port_unoffload, otherwise the bridge will treat the
port as non-offloaded and allow software flooding to other ports from
the same ASIC.

Note that these functions lay the ground for a more complex handshake
between switchdev drivers and the bridge in the future.

For drivers that will request a replay of the switchdev objects when
they offload and unoffload a bridge port (DSA, dpaa2-switch, ocelot), we
place the call to switchdev_bridge_port_unoffload() strategically inside
the NETDEV_PRECHANGEUPPER notifier's code path, and not inside
NETDEV_CHANGEUPPER. This is because the switchdev object replay helpers
need the netdev adjacency lists to be valid, and that is only true in
NETDEV_PRECHANGEUPPER.

Cc: Vadym Kochan <vkochan at marvell.com>
Cc: Taras Chornyi <tchornyi at marvell.com>
Cc: Ioana Ciornei <ioana.ciornei at nxp.com>
Cc: Lars Povlsen <lars.povlsen at microchip.com>
Cc: Steen Hegelund <Steen.Hegelund at microchip.com>
Cc: UNGLinuxDriver at microchip.com
Cc: Claudiu Manoil <claudiu.manoil at nxp.com>
Cc: Alexandre Belloni <alexandre.belloni at bootlin.com>
Cc: Grygorii Strashko <grygorii.strashko at ti.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean at nxp.com>
Tested-by: Ioana Ciornei <ioana.ciornei at nxp.com> # dpaa2-switch:
regression
Acked-by: Ioana Ciornei <ioana.ciornei at nxp.com> # dpaa2-switch
Tested-by: Horatiu Vultur <horatiu.vultur at microchip.com> #
ocelot-switch
---
v2->v3: patch is new
v3->v4: added mlxsw_sp_port_pre_lag_leave() and
mlxsw_sp_port_pre_vlan_leave()
v4->v5: use for the comparison in nbp_switchdev_hwdom_set() the
        nbp->ppid provided by switchdev_bridge_port_offload() instead of
        recursing through the lower interfaces of the nbp->dev
v5->v6:
- add error handling to dpaa2-switch
- drop useless arguments from switchdev_bridge_port_unoffload(): dev,
  extack, and make it return void
- stop reworking as deeply the drivers where no replays will be
  requested for now, and just call the offload/unoffload helpers where
  it is most convenient.

 .../ethernet/freescale/dpaa2/dpaa2-switch.c   | 13 +++
 .../ethernet/marvell/prestera/prestera_main.c |  3 +-
 .../marvell/prestera/prestera_switchdev.c     | 11 ++-
 .../marvell/prestera/prestera_switchdev.h     |  3 +-
 .../mellanox/mlxsw/spectrum_switchdev.c       | 24 ++++--
 .../microchip/sparx5/sparx5_switchdev.c       | 23 +++++-
 drivers/net/ethernet/mscc/ocelot_net.c        | 71 ++++++++++++++++
 drivers/net/ethernet/rocker/rocker.h          |  3 +-
 drivers/net/ethernet/rocker/rocker_main.c     |  9 +-
 drivers/net/ethernet/rocker/rocker_ofdpa.c    | 18 +++-
 drivers/net/ethernet/ti/am65-cpsw-nuss.c      | 17 +++-
 drivers/net/ethernet/ti/cpsw_new.c            | 15 +++-
 include/linux/if_bridge.h                     | 21 +++++
 net/bridge/br_if.c                            | 13 +--
 net/bridge/br_private.h                       | 13 +--
 net/bridge/br_switchdev.c                     | 82 ++++++++++++++++---
 net/dsa/port.c                                | 16 +++-
 17 files changed, 298 insertions(+), 57 deletions(-)

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
index 23798feb40b2..9b090da3e460 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
@@ -1930,8 +1930,13 @@ static int dpaa2_switch_port_bridge_join(struct
net_device *netdev,
 	if (err)
 		goto err_egress_flood;
 
+	err = switchdev_bridge_port_offload(netdev, netdev, extack);
+	if (err)
+		goto err_switchdev_offload;
+
 	return 0;
 
+err_switchdev_offload:
 err_egress_flood:
 	dpaa2_switch_port_set_fdb(port_priv, NULL);
 	return err;
@@ -1957,6 +1962,11 @@ static int dpaa2_switch_port_restore_rxvlan(struct
net_device *vdev, int vid, vo
 	return dpaa2_switch_port_vlan_add(arg, vlan_proto, vid);
 }
 
+static void dpaa2_switch_port_pre_bridge_leave(struct net_device *netdev)
+{
+	switchdev_bridge_port_unoffload(netdev);
+}
+
 static int dpaa2_switch_port_bridge_leave(struct net_device *netdev)
 {
 	struct ethsw_port_priv *port_priv = netdev_priv(netdev);
@@ -2078,6 +2088,9 @@ static int dpaa2_switch_port_netdevice_event(struct
notifier_block *nb,
 		if (err)
 			goto out;
 
+		if (!info->linking)
+			dpaa2_switch_port_pre_bridge_leave(netdev);
+
 		break;
 	case NETDEV_CHANGEUPPER:
 		upper_dev = info->upper_dev;
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_main.c
b/drivers/net/ethernet/marvell/prestera/prestera_main.c
index 226f4ff29f6e..7c569c1abefc 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_main.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_main.c
@@ -746,7 +746,8 @@ static int prestera_netdev_port_event(struct net_device
*lower,
 	case NETDEV_CHANGEUPPER:
 		if (netif_is_bridge_master(upper)) {
 			if (info->linking)
-				return prestera_bridge_port_join(upper, port);
+				return prestera_bridge_port_join(upper, port,
+								 extack);
 			else
 				prestera_bridge_port_leave(upper, port);
 		} else if (netif_is_lag_master(upper)) {
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
b/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
index 0b3e8f2db294..8cf3fe3b7e58 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
@@ -480,7 +480,8 @@ prestera_bridge_1d_port_join(struct prestera_bridge_port
*br_port)
 }
 
 int prestera_bridge_port_join(struct net_device *br_dev,
-			      struct prestera_port *port)
+			      struct prestera_port *port,
+			      struct netlink_ext_ack *extack)
 {
 	struct prestera_switchdev *swdev = port->sw->swdev;
 	struct prestera_bridge_port *br_port;
@@ -500,6 +501,10 @@ int prestera_bridge_port_join(struct net_device *br_dev,
 		goto err_brport_create;
 	}
 
+	err = switchdev_bridge_port_offload(br_port->dev, port->dev, extack);
+	if (err)
+		goto err_switchdev_offload;
+
 	if (bridge->vlan_enabled)
 		return 0;
 
@@ -510,6 +515,8 @@ int prestera_bridge_port_join(struct net_device *br_dev,
 	return 0;
 
 err_port_join:
+	switchdev_bridge_port_unoffload(br_port->dev);
+err_switchdev_offload:
 	prestera_bridge_port_put(br_port);
 err_brport_create:
 	prestera_bridge_put(bridge);
@@ -584,6 +591,8 @@ void prestera_bridge_port_leave(struct net_device *br_dev,
 	else
 		prestera_bridge_1d_port_leave(br_port);
 
+	switchdev_bridge_port_unoffload(br_port->dev);
+
 	prestera_hw_port_learning_set(port, false);
 	prestera_hw_port_flood_set(port, BR_FLOOD | BR_MCAST_FLOOD, 0);
 	prestera_port_vid_stp_set(port, PRESTERA_VID_ALL, BR_STATE_FORWARDING);
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_switchdev.h
b/drivers/net/ethernet/marvell/prestera/prestera_switchdev.h
index a91bc35d235f..0e93fda3d9a5 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_switchdev.h
+++ b/drivers/net/ethernet/marvell/prestera/prestera_switchdev.h
@@ -8,7 +8,8 @@ int prestera_switchdev_init(struct prestera_switch *sw);
 void prestera_switchdev_fini(struct prestera_switch *sw);
 
 int prestera_bridge_port_join(struct net_device *br_dev,
-			      struct prestera_port *port);
+			      struct prestera_port *port,
+			      struct netlink_ext_ack *extack);
 
 void prestera_bridge_port_leave(struct net_device *br_dev,
 				struct prestera_port *port);
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
b/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
index 61911fed6aeb..c52317de1f35 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
@@ -335,14 +335,16 @@ mlxsw_sp_bridge_port_find(struct mlxsw_sp_bridge *bridge,
 
 static struct mlxsw_sp_bridge_port *
 mlxsw_sp_bridge_port_create(struct mlxsw_sp_bridge_device *bridge_device,
-			    struct net_device *brport_dev)
+			    struct net_device *brport_dev,
+			    struct netlink_ext_ack *extack)
 {
 	struct mlxsw_sp_bridge_port *bridge_port;
 	struct mlxsw_sp_port *mlxsw_sp_port;
+	int err;
 
 	bridge_port = kzalloc(sizeof(*bridge_port), GFP_KERNEL);
 	if (!bridge_port)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	mlxsw_sp_port = mlxsw_sp_port_dev_lower_find(brport_dev);
 	bridge_port->lagged = mlxsw_sp_port->lagged;
@@ -359,12 +361,23 @@ mlxsw_sp_bridge_port_create(struct mlxsw_sp_bridge_device
*bridge_device,
 	list_add(&bridge_port->list, &bridge_device->ports_list);
 	bridge_port->ref_count = 1;
 
+	err = switchdev_bridge_port_offload(brport_dev, mlxsw_sp_port->dev,
+					    extack);
+	if (err)
+		goto err_switchdev_offload;
+
 	return bridge_port;
+
+err_switchdev_offload:
+	list_del(&bridge_port->list);
+	kfree(bridge_port);
+	return ERR_PTR(err);
 }
 
 static void
 mlxsw_sp_bridge_port_destroy(struct mlxsw_sp_bridge_port *bridge_port)
 {
+	switchdev_bridge_port_unoffload(bridge_port->dev);
 	list_del(&bridge_port->list);
 	WARN_ON(!list_empty(&bridge_port->vlans_list));
 	kfree(bridge_port);
@@ -390,9 +403,10 @@ mlxsw_sp_bridge_port_get(struct mlxsw_sp_bridge *bridge,
 	if (IS_ERR(bridge_device))
 		return ERR_CAST(bridge_device);
 
-	bridge_port = mlxsw_sp_bridge_port_create(bridge_device, brport_dev);
-	if (!bridge_port) {
-		err = -ENOMEM;
+	bridge_port = mlxsw_sp_bridge_port_create(bridge_device, brport_dev,
+						  extack);
+	if (IS_ERR(bridge_port)) {
+		err = PTR_ERR(bridge_port);
 		goto err_bridge_port_create;
 	}
 
diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
b/drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
index a72e3b3b596e..e4fb573563d0 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
@@ -93,9 +93,12 @@ static int sparx5_port_attr_set(struct net_device *dev, const
void *ctx,
 }
 
 static int sparx5_port_bridge_join(struct sparx5_port *port,
-				   struct net_device *bridge)
+				   struct net_device *bridge,
+				   struct netlink_ext_ack *extack)
 {
 	struct sparx5 *sparx5 = port->sparx5;
+	struct net_device *ndev = port->ndev;
+	int err;
 
 	if (bitmap_empty(sparx5->bridge_mask, SPX5_PORTS))
 		/* First bridged port */
@@ -109,12 +112,20 @@ static int sparx5_port_bridge_join(struct sparx5_port
*port,
 
 	set_bit(port->portno, sparx5->bridge_mask);
 
+	err = switchdev_bridge_port_offload(ndev, ndev, extack);
+	if (err)
+		goto err_switchdev_offload;
+
 	/* Port enters in bridge mode therefor don't need to copy to CPU
 	 * frames for multicast in case the bridge is not requesting them
 	 */
-	__dev_mc_unsync(port->ndev, sparx5_mc_unsync);
+	__dev_mc_unsync(ndev, sparx5_mc_unsync);
 
 	return 0;
+
+err_switchdev_offload:
+	clear_bit(port->portno, sparx5->bridge_mask);
+	return err;
 }
 
 static void sparx5_port_bridge_leave(struct sparx5_port *port,
@@ -122,6 +133,8 @@ static void sparx5_port_bridge_leave(struct sparx5_port
*port,
 {
 	struct sparx5 *sparx5 = port->sparx5;
 
+	switchdev_bridge_port_unoffload(port->ndev);
+
 	clear_bit(port->portno, sparx5->bridge_mask);
 	if (bitmap_empty(sparx5->bridge_mask, SPX5_PORTS))
 		sparx5->hw_bridge_dev = NULL;
@@ -139,11 +152,15 @@ static int sparx5_port_changeupper(struct net_device *dev,
 				   struct netdev_notifier_changeupper_info *info)
 {
 	struct sparx5_port *port = netdev_priv(dev);
+	struct netlink_ext_ack *extack;
 	int err = 0;
 
+	extack = netdev_notifier_info_to_extack(&info->info);
+
 	if (netif_is_bridge_master(info->upper_dev)) {
 		if (info->linking)
-			err = sparx5_port_bridge_join(port, info->upper_dev);
+			err = sparx5_port_bridge_join(port, info->upper_dev,
+						      extack);
 		else
 			sparx5_port_bridge_leave(port, info->upper_dev);
 
diff --git a/drivers/net/ethernet/mscc/ocelot_net.c
b/drivers/net/ethernet/mscc/ocelot_net.c
index e9d260d84bf3..76b7b9536bf7 100644
--- a/drivers/net/ethernet/mscc/ocelot_net.c
+++ b/drivers/net/ethernet/mscc/ocelot_net.c
@@ -1216,6 +1216,10 @@ static int ocelot_netdevice_bridge_join(struct net_device
*dev,
 
 	ocelot_port_bridge_join(ocelot, port, bridge);
 
+	err = switchdev_bridge_port_offload(brport_dev, dev, extack);
+	if (err)
+		goto err_switchdev_offload;
+
 	err = ocelot_switchdev_sync(ocelot, port, brport_dev, bridge, extack);
 	if (err)
 		goto err_switchdev_sync;
@@ -1223,10 +1227,17 @@ static int ocelot_netdevice_bridge_join(struct
net_device *dev,
 	return 0;
 
 err_switchdev_sync:
+	switchdev_bridge_port_unoffload(brport_dev);
+err_switchdev_offload:
 	ocelot_port_bridge_leave(ocelot, port, bridge);
 	return err;
 }
 
+static void ocelot_netdevice_pre_bridge_leave(struct net_device *brport_dev)
+{
+	switchdev_bridge_port_unoffload(brport_dev);
+}
+
 static int ocelot_netdevice_bridge_leave(struct net_device *dev,
 					 struct net_device *brport_dev,
 					 struct net_device *bridge)
@@ -1279,6 +1290,18 @@ static int ocelot_netdevice_lag_join(struct net_device
*dev,
 	return err;
 }
 
+static void ocelot_netdevice_pre_lag_leave(struct net_device *dev,
+					   struct net_device *bond)
+{
+	struct net_device *bridge_dev;
+
+	bridge_dev = netdev_master_upper_dev_get(bond);
+	if (!bridge_dev || !netif_is_bridge_master(bridge_dev))
+		return;
+
+	ocelot_netdevice_pre_bridge_leave(bond);
+}
+
 static int ocelot_netdevice_lag_leave(struct net_device *dev,
 				      struct net_device *bond)
 {
@@ -1355,6 +1378,43 @@ ocelot_netdevice_lag_changeupper(struct net_device *dev,
 	return NOTIFY_DONE;
 }
 
+static int
+ocelot_netdevice_prechangeupper(struct net_device *dev,
+				struct net_device *brport_dev,
+				struct netdev_notifier_changeupper_info *info)
+{
+	if (netif_is_bridge_master(info->upper_dev) && !info->linking)
+		ocelot_netdevice_pre_bridge_leave(brport_dev);
+
+	if (netif_is_lag_master(info->upper_dev) && !info->linking)
+		ocelot_netdevice_pre_lag_leave(dev, info->upper_dev);
+
+	return NOTIFY_DONE;
+}
+
+static int
+ocelot_netdevice_lag_prechangeupper(struct net_device *dev,
+				    struct netdev_notifier_changeupper_info *info)
+{
+	struct net_device *lower;
+	struct list_head *iter;
+	int err = NOTIFY_DONE;
+
+	netdev_for_each_lower_dev(dev, lower, iter) {
+		struct ocelot_port_private *priv = netdev_priv(lower);
+		struct ocelot_port *ocelot_port = &priv->port;
+
+		if (ocelot_port->bond != dev)
+			return NOTIFY_OK;
+
+		err = ocelot_netdevice_prechangeupper(dev, lower, info);
+		if (err)
+			return err;
+	}
+
+	return NOTIFY_DONE;
+}
+
 static int
 ocelot_netdevice_changelowerstate(struct net_device *dev,
 				  struct netdev_lag_lower_state_info *info)
@@ -1382,6 +1442,17 @@ static int ocelot_netdevice_event(struct notifier_block
*unused,
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 
 	switch (event) {
+	case NETDEV_PRECHANGEUPPER: {
+		struct netdev_notifier_changeupper_info *info = ptr;
+
+		if (ocelot_netdevice_dev_check(dev))
+			return ocelot_netdevice_prechangeupper(dev, dev, info);
+
+		if (netif_is_lag_master(dev))
+			return ocelot_netdevice_lag_prechangeupper(dev, info);
+
+		break;
+	}
 	case NETDEV_CHANGEUPPER: {
 		struct netdev_notifier_changeupper_info *info = ptr;
 
diff --git a/drivers/net/ethernet/rocker/rocker.h
b/drivers/net/ethernet/rocker/rocker.h
index 315a6e5c0f59..e75814a4654f 100644
--- a/drivers/net/ethernet/rocker/rocker.h
+++ b/drivers/net/ethernet/rocker/rocker.h
@@ -119,7 +119,8 @@ struct rocker_world_ops {
 	int (*port_obj_fdb_del)(struct rocker_port *rocker_port,
 				u16 vid, const unsigned char *addr);
 	int (*port_master_linked)(struct rocker_port *rocker_port,
-				  struct net_device *master);
+				  struct net_device *master,
+				  struct netlink_ext_ack *extack);
 	int (*port_master_unlinked)(struct rocker_port *rocker_port,
 				    struct net_device *master);
 	int (*port_neigh_update)(struct rocker_port *rocker_port,
diff --git a/drivers/net/ethernet/rocker/rocker_main.c
b/drivers/net/ethernet/rocker/rocker_main.c
index a46633606cae..53d407a5dbf7 100644
--- a/drivers/net/ethernet/rocker/rocker_main.c
+++ b/drivers/net/ethernet/rocker/rocker_main.c
@@ -1670,13 +1670,14 @@ rocker_world_port_fdb_del(struct rocker_port
*rocker_port,
 }
 
 static int rocker_world_port_master_linked(struct rocker_port *rocker_port,
-					   struct net_device *master)
+					   struct net_device *master,
+					   struct netlink_ext_ack *extack)
 {
 	struct rocker_world_ops *wops = rocker_port->rocker->wops;
 
 	if (!wops->port_master_linked)
 		return -EOPNOTSUPP;
-	return wops->port_master_linked(rocker_port, master);
+	return wops->port_master_linked(rocker_port, master, extack);
 }
 
 static int rocker_world_port_master_unlinked(struct rocker_port *rocker_port,
@@ -3107,6 +3108,7 @@ struct rocker_port *rocker_port_dev_lower_find(struct
net_device *dev,
 static int rocker_netdevice_event(struct notifier_block *unused,
 				  unsigned long event, void *ptr)
 {
+	struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr);
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct netdev_notifier_changeupper_info *info;
 	struct rocker_port *rocker_port;
@@ -3123,7 +3125,8 @@ static int rocker_netdevice_event(struct notifier_block
*unused,
 		rocker_port = netdev_priv(dev);
 		if (info->linking) {
 			err = rocker_world_port_master_linked(rocker_port,
-							      info->upper_dev);
+							      info->upper_dev,
+							      extack);
 			if (err)
 				netdev_warn(dev, "failed to reflect master linked (err %d)\n",
 					    err);
diff --git a/drivers/net/ethernet/rocker/rocker_ofdpa.c
b/drivers/net/ethernet/rocker/rocker_ofdpa.c
index 967a634ee9ac..84dcaf8687a0 100644
--- a/drivers/net/ethernet/rocker/rocker_ofdpa.c
+++ b/drivers/net/ethernet/rocker/rocker_ofdpa.c
@@ -2571,8 +2571,10 @@ static int ofdpa_port_obj_fdb_del(struct rocker_port
*rocker_port,
 }
 
 static int ofdpa_port_bridge_join(struct ofdpa_port *ofdpa_port,
-				  struct net_device *bridge)
+				  struct net_device *bridge,
+				  struct netlink_ext_ack *extack)
 {
+	struct net_device *dev = ofdpa_port->dev;
 	int err;
 
 	/* Port is joining bridge, so the internal VLAN for the
@@ -2592,13 +2594,20 @@ static int ofdpa_port_bridge_join(struct ofdpa_port
*ofdpa_port,
 
 	ofdpa_port->bridge_dev = bridge;
 
-	return ofdpa_port_vlan_add(ofdpa_port, OFDPA_UNTAGGED_VID, 0);
+	err = ofdpa_port_vlan_add(ofdpa_port, OFDPA_UNTAGGED_VID, 0);
+	if (err)
+		return err;
+
+	return switchdev_bridge_port_offload(dev, dev, extack);
 }
 
 static int ofdpa_port_bridge_leave(struct ofdpa_port *ofdpa_port)
 {
+	struct net_device *dev = ofdpa_port->dev;
 	int err;
 
+	switchdev_bridge_port_unoffload(dev);
+
 	err = ofdpa_port_vlan_del(ofdpa_port, OFDPA_UNTAGGED_VID, 0);
 	if (err)
 		return err;
@@ -2637,13 +2646,14 @@ static int ofdpa_port_ovs_changed(struct ofdpa_port
*ofdpa_port,
 }
 
 static int ofdpa_port_master_linked(struct rocker_port *rocker_port,
-				    struct net_device *master)
+				    struct net_device *master,
+				    struct netlink_ext_ack *extack)
 {
 	struct ofdpa_port *ofdpa_port = rocker_port->wpriv;
 	int err = 0;
 
 	if (netif_is_bridge_master(master))
-		err = ofdpa_port_bridge_join(ofdpa_port, master);
+		err = ofdpa_port_bridge_join(ofdpa_port, master, extack);
 	else if (netif_is_ovs_master(master))
 		err = ofdpa_port_ovs_changed(ofdpa_port, master);
 	return err;
diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index 718539cdd2f2..8b9596eb808e 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -7,6 +7,7 @@
 
 #include <linux/clk.h>
 #include <linux/etherdevice.h>
+#include <linux/if_bridge.h>
 #include <linux/if_vlan.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
@@ -2077,10 +2078,13 @@ bool am65_cpsw_port_dev_check(const struct net_device
*ndev)
 	return false;
 }
 
-static int am65_cpsw_netdevice_port_link(struct net_device *ndev, struct
net_device *br_ndev)
+static int am65_cpsw_netdevice_port_link(struct net_device *ndev,
+					 struct net_device *br_ndev,
+					 struct netlink_ext_ack *extack)
 {
 	struct am65_cpsw_common *common = am65_ndev_to_common(ndev);
 	struct am65_cpsw_ndev_priv *priv = am65_ndev_to_priv(ndev);
+	int err;
 
 	if (!common->br_members) {
 		common->hw_bridge_dev = br_ndev;
@@ -2092,6 +2096,10 @@ static int am65_cpsw_netdevice_port_link(struct
net_device *ndev, struct net_dev
 			return -EOPNOTSUPP;
 	}
 
+	err = switchdev_bridge_port_offload(ndev, ndev, extack);
+	if (err)
+		return err;
+
 	common->br_members |= BIT(priv->port->port_id);
 
 	am65_cpsw_port_offload_fwd_mark_update(common);
@@ -2104,6 +2112,8 @@ static void am65_cpsw_netdevice_port_unlink(struct
net_device *ndev)
 	struct am65_cpsw_common *common = am65_ndev_to_common(ndev);
 	struct am65_cpsw_ndev_priv *priv = am65_ndev_to_priv(ndev);
 
+	switchdev_bridge_port_unoffload(ndev);
+
 	common->br_members &= ~BIT(priv->port->port_id);
 
 	am65_cpsw_port_offload_fwd_mark_update(common);
@@ -2116,6 +2126,7 @@ static void am65_cpsw_netdevice_port_unlink(struct
net_device *ndev)
 static int am65_cpsw_netdevice_event(struct notifier_block *unused,
 				     unsigned long event, void *ptr)
 {
+	struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr);
 	struct net_device *ndev = netdev_notifier_info_to_dev(ptr);
 	struct netdev_notifier_changeupper_info *info;
 	int ret = NOTIFY_DONE;
@@ -2129,7 +2140,9 @@ static int am65_cpsw_netdevice_event(struct notifier_block
*unused,
 
 		if (netif_is_bridge_master(info->upper_dev)) {
 			if (info->linking)
-				ret = am65_cpsw_netdevice_port_link(ndev, info->upper_dev);
+				ret = am65_cpsw_netdevice_port_link(ndev,
+								    info->upper_dev,
+								    extack);
 			else
 				am65_cpsw_netdevice_port_unlink(ndev);
 		}
diff --git a/drivers/net/ethernet/ti/cpsw_new.c
b/drivers/net/ethernet/ti/cpsw_new.c
index 57d279fdcc9f..bf9cadfb11b5 100644
--- a/drivers/net/ethernet/ti/cpsw_new.c
+++ b/drivers/net/ethernet/ti/cpsw_new.c
@@ -11,6 +11,7 @@
 #include <linux/module.h>
 #include <linux/irqreturn.h>
 #include <linux/interrupt.h>
+#include <linux/if_bridge.h>
 #include <linux/if_ether.h>
 #include <linux/etherdevice.h>
 #include <linux/net_tstamp.h>
@@ -1499,10 +1500,12 @@ static void cpsw_port_offload_fwd_mark_update(struct
cpsw_common *cpsw)
 }
 
 static int cpsw_netdevice_port_link(struct net_device *ndev,
-				    struct net_device *br_ndev)
+				    struct net_device *br_ndev,
+				    struct netlink_ext_ack *extack)
 {
 	struct cpsw_priv *priv = netdev_priv(ndev);
 	struct cpsw_common *cpsw = priv->cpsw;
+	int err;
 
 	if (!cpsw->br_members) {
 		cpsw->hw_bridge_dev = br_ndev;
@@ -1514,6 +1517,10 @@ static int cpsw_netdevice_port_link(struct net_device
*ndev,
 			return -EOPNOTSUPP;
 	}
 
+	err = switchdev_bridge_port_offload(ndev, ndev, extack);
+	if (err)
+		return err;
+
 	cpsw->br_members |= BIT(priv->emac_port);
 
 	cpsw_port_offload_fwd_mark_update(cpsw);
@@ -1526,6 +1533,8 @@ static void cpsw_netdevice_port_unlink(struct net_device
*ndev)
 	struct cpsw_priv *priv = netdev_priv(ndev);
 	struct cpsw_common *cpsw = priv->cpsw;
 
+	switchdev_bridge_port_unoffload(ndev);
+
 	cpsw->br_members &= ~BIT(priv->emac_port);
 
 	cpsw_port_offload_fwd_mark_update(cpsw);
@@ -1538,6 +1547,7 @@ static void cpsw_netdevice_port_unlink(struct net_device
*ndev)
 static int cpsw_netdevice_event(struct notifier_block *unused,
 				unsigned long event, void *ptr)
 {
+	struct netlink_ext_ack *extack = netdev_notifier_info_to_extack(ptr);
 	struct net_device *ndev = netdev_notifier_info_to_dev(ptr);
 	struct netdev_notifier_changeupper_info *info;
 	int ret = NOTIFY_DONE;
@@ -1552,7 +1562,8 @@ static int cpsw_netdevice_event(struct notifier_block
*unused,
 		if (netif_is_bridge_master(info->upper_dev)) {
 			if (info->linking)
 				ret = cpsw_netdevice_port_link(ndev,
-							       info->upper_dev);
+							       info->upper_dev,
+							       extack);
 			else
 				cpsw_netdevice_port_unlink(ndev);
 		}
diff --git a/include/linux/if_bridge.h b/include/linux/if_bridge.h
index b651c5e32a28..ce413eca527e 100644
--- a/include/linux/if_bridge.h
+++ b/include/linux/if_bridge.h
@@ -206,4 +206,25 @@ static inline int br_fdb_replay(const struct net_device
*br_dev,
 }
 #endif
 
+#if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_NET_SWITCHDEV)
+
+int switchdev_bridge_port_offload(struct net_device *brport_dev,
+				  struct net_device *dev,
+				  struct netlink_ext_ack *extack);
+void switchdev_bridge_port_unoffload(struct net_device *brport_dev);
+
+#else
+
+static inline int switchdev_bridge_port_offload(struct net_device *brport_dev,
+						struct net_device *dev,
+						struct netlink_ext_ack *extack)
+{
+	return -EINVAL;
+}
+
+static inline void switchdev_bridge_port_unoffload(struct net_device
*brport_dev)
+{
+}
+#endif
+
 #endif
diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
index c0df50e4abbb..86f6d7e93ea8 100644
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
@@ -349,7 +349,6 @@ static void del_nbp(struct net_bridge_port *p)
 	nbp_backup_clear(p);
 
 	nbp_update_port_count(br);
-	nbp_switchdev_del(p);
 
 	netdev_upper_dev_unlink(dev, br->dev);
 
@@ -644,10 +643,6 @@ int br_add_if(struct net_bridge *br, struct net_device
*dev,
 	if (err)
 		goto err5;
 
-	err = nbp_switchdev_add(p);
-	if (err)
-		goto err6;
-
 	dev_disable_lro(dev);
 
 	list_add_rcu(&p->list, &br->port_list);
@@ -685,13 +680,13 @@ int br_add_if(struct net_bridge *br, struct net_device
*dev,
 		 */
 		err = dev_pre_changeaddr_notify(br->dev, dev->dev_addr, extack);
 		if (err)
-			goto err7;
+			goto err6;
 	}
 
 	err = nbp_vlan_init(p, extack);
 	if (err) {
 		netdev_err(dev, "failed to initialize vlan filtering on this
port\n");
-		goto err7;
+		goto err6;
 	}
 
 	spin_lock_bh(&br->lock);
@@ -714,14 +709,12 @@ int br_add_if(struct net_bridge *br, struct net_device
*dev,
 
 	return 0;
 
-err7:
+err6:
 	if (fdb_synced)
 		br_fdb_unsync_static(br, p);
 	list_del_rcu(&p->list);
 	br_fdb_delete_by_port(br, p, 0, 1);
 	nbp_update_port_count(br);
-	nbp_switchdev_del(p);
-err6:
 	netdev_upper_dev_unlink(dev, br->dev);
 err5:
 	dev->priv_flags &= ~IFF_BRIDGE_PORT;
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 1c1732d7212a..8d2e4d807808 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -392,6 +392,8 @@ struct net_bridge_port {
 	 * hardware domain.
 	 */
 	int				hwdom;
+	int				offload_count;
+	struct netdev_phys_item_id	ppid;
 #endif
 	u16				group_fwd_mask;
 	u16				backup_redirected_cnt;
@@ -1856,8 +1858,6 @@ void br_switchdev_fdb_notify(struct net_bridge *br,
 int br_switchdev_port_vlan_add(struct net_device *dev, u16 vid, u16 flags,
 			       struct netlink_ext_ack *extack);
 int br_switchdev_port_vlan_del(struct net_device *dev, u16 vid);
-int nbp_switchdev_add(struct net_bridge_port *p);
-void nbp_switchdev_del(struct net_bridge_port *p);
 void br_switchdev_init(struct net_bridge *br);
 
 static inline void br_switchdev_frame_unmark(struct sk_buff *skb)
@@ -1906,15 +1906,6 @@ static inline void br_switchdev_frame_unmark(struct
sk_buff *skb)
 {
 }
 
-static inline int nbp_switchdev_add(struct net_bridge_port *p)
-{
-	return 0;
-}
-
-static inline void nbp_switchdev_del(struct net_bridge_port *p)
-{
-}
-
 static inline void br_switchdev_init(struct net_bridge *br)
 {
 }
diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
index f3120f13c293..39f0787fde01 100644
--- a/net/bridge/br_switchdev.c
+++ b/net/bridge/br_switchdev.c
@@ -133,7 +133,7 @@ static int nbp_switchdev_hwdom_set(struct net_bridge_port
*joining)
 
 	/* joining is yet to be added to the port list. */
 	list_for_each_entry(p, &br->port_list, list) {
-		if (netdev_port_same_parent_id(joining->dev, p->dev)) {
+		if (netdev_phys_item_id_same(&joining->ppid, &p->ppid)) {
 			joining->hwdom = p->hwdom;
 			return 0;
 		}
@@ -162,27 +162,85 @@ static void nbp_switchdev_hwdom_put(struct net_bridge_port
*leaving)
 	clear_bit(leaving->hwdom, &br->busy_hwdoms);
 }
 
-int nbp_switchdev_add(struct net_bridge_port *p)
+static int nbp_switchdev_add(struct net_bridge_port *p,
+			     struct netdev_phys_item_id ppid,
+			     struct netlink_ext_ack *extack)
 {
-	struct netdev_phys_item_id ppid = { };
-	int err;
+	if (p->offload_count) {
+		/* Prevent unsupported configurations such as a bridge port
+		 * which is a bonding interface, and the member ports are from
+		 * different hardware switches.
+		 */
+		if (!netdev_phys_item_id_same(&p->ppid, &ppid)) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "Same bridge port cannot be offloaded by two physical
switches");
+			return -EBUSY;
+		}
 
-	ASSERT_RTNL();
+		/* Tolerate drivers that call switchdev_bridge_port_offload()
+		 * more than once for the same bridge port, such as when the
+		 * bridge port is an offloaded bonding/team interface.
+		 */
+		p->offload_count++;
 
-	err = dev_get_port_parent_id(p->dev, &ppid, true);
-	if (err) {
-		if (err == -EOPNOTSUPP)
-			return 0;
-		return err;
+		return 0;
 	}
 
+	p->ppid = ppid;
+	p->offload_count = 1;
+
 	return nbp_switchdev_hwdom_set(p);
 }
 
-void nbp_switchdev_del(struct net_bridge_port *p)
+static void nbp_switchdev_del(struct net_bridge_port *p)
 {
-	ASSERT_RTNL();
+	if (WARN_ON(!p->offload_count))
+		return;
+
+	p->offload_count--;
+
+	if (p->offload_count)
+		return;
 
 	if (p->hwdom)
 		nbp_switchdev_hwdom_put(p);
 }
+
+/* Let the bridge know that this port is offloaded, so that it can assign a
+ * switchdev hardware domain to it.
+ */
+int switchdev_bridge_port_offload(struct net_device *brport_dev,
+				  struct net_device *dev,
+				  struct netlink_ext_ack *extack)
+{
+	struct netdev_phys_item_id ppid;
+	struct net_bridge_port *p;
+	int err;
+
+	ASSERT_RTNL();
+
+	p = br_port_get_rtnl(brport_dev);
+	if (!p)
+		return -ENODEV;
+
+	err = dev_get_port_parent_id(dev, &ppid, false);
+	if (err)
+		return err;
+
+	return nbp_switchdev_add(p, ppid, extack);
+}
+EXPORT_SYMBOL_GPL(switchdev_bridge_port_offload);
+
+void switchdev_bridge_port_unoffload(struct net_device *brport_dev)
+{
+	struct net_bridge_port *p;
+
+	ASSERT_RTNL();
+
+	p = br_port_get_rtnl(brport_dev);
+	if (!p)
+		return;
+
+	nbp_switchdev_del(p);
+}
+EXPORT_SYMBOL_GPL(switchdev_bridge_port_unoffload);
diff --git a/net/dsa/port.c b/net/dsa/port.c
index 982e18771d76..7accda066149 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -292,6 +292,8 @@ int dsa_port_bridge_join(struct dsa_port *dp, struct
net_device *br,
 		.port = dp->index,
 		.br = br,
 	};
+	struct net_device *dev = dp->slave;
+	struct net_device *brport_dev;
 	int err;
 
 	/* Here the interface is already bridged. Reflect the current
@@ -299,16 +301,24 @@ int dsa_port_bridge_join(struct dsa_port *dp, struct
net_device *br,
 	 */
 	dp->bridge_dev = br;
 
+	brport_dev = dsa_port_to_bridge_port(dp);
+
 	err = dsa_broadcast(DSA_NOTIFIER_BRIDGE_JOIN, &info);
 	if (err)
 		goto out_rollback;
 
-	err = dsa_port_switchdev_sync(dp, extack);
+	err = switchdev_bridge_port_offload(brport_dev, dev, extack);
 	if (err)
 		goto out_rollback_unbridge;
 
+	err = dsa_port_switchdev_sync(dp, extack);
+	if (err)
+		goto out_rollback_unoffload;
+
 	return 0;
 
+out_rollback_unoffload:
+	switchdev_bridge_port_unoffload(brport_dev);
 out_rollback_unbridge:
 	dsa_broadcast(DSA_NOTIFIER_BRIDGE_LEAVE, &info);
 out_rollback:
@@ -319,6 +329,10 @@ int dsa_port_bridge_join(struct dsa_port *dp, struct
net_device *br,
 int dsa_port_pre_bridge_leave(struct dsa_port *dp, struct net_device *br,
 			      struct netlink_ext_ack *extack)
 {
+	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
+
+	switchdev_bridge_port_unoffload(brport_dev);
+
 	return dsa_port_switchdev_unsync_objs(dp, br, extack);
 }
 
-- 
2.25.1

There is a desire to make the object and FDB replay helpers optional
when moving them inside the bridge driver. For example a certain driver
might not offload host MDBs and there is no case where the replay
helpers would be of immediate use to it.

So it would be nice if we could allow drivers to pass NULL pointers for
the atomic and blocking notifier blocks, and the replay helpers to do
nothing in that case.

Signed-off-by: Vladimir Oltean <vladimir.oltean at nxp.com>
---
 net/bridge/br_fdb.c  | 3 +++
 net/bridge/br_mdb.c  | 3 +++
 net/bridge/br_vlan.c | 3 +++
 3 files changed, 9 insertions(+)

diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index 2b862cffc03a..47f190b6bfa3 100644
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -760,6 +760,9 @@ int br_fdb_replay(const struct net_device *br_dev, const
struct net_device *dev,
 	unsigned long action;
 	int err = 0;
 
+	if (!nb)
+		return 0;
+
 	if (!netif_is_bridge_master(br_dev))
 		return -EINVAL;
 
diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index d3383a47a2f2..09358c475787 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -617,6 +617,9 @@ int br_mdb_replay(struct net_device *br_dev, struct
net_device *dev,
 
 	ASSERT_RTNL();
 
+	if (!nb)
+		return 0;
+
 	if (!netif_is_bridge_master(br_dev) || !netif_is_bridge_port(dev))
 		return -EINVAL;
 
diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c
index e66b004df763..45ef07f682f1 100644
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -1856,6 +1856,9 @@ int br_vlan_replay(struct net_device *br_dev, struct
net_device *dev,
 
 	ASSERT_RTNL();
 
+	if (!nb)
+		return 0;
+
 	if (!netif_is_bridge_master(br_dev))
 		return -EINVAL;
 
-- 
2.25.1

Starting with commit 4f2673b3a2b6 ("net: bridge: add helper to replay
port and host-joined mdb entries"), DSA has introduced some bridge
helpers that replay switchdev events (FDB/MDB/VLAN additions and
deletions) that can be lost by the switchdev drivers in a variety of
circumstances:

- an IP multicast group was host-joined on the bridge itself before any
  switchdev port joined the bridge, leading to the host MDB entries
  missing in the hardware database.
- during the bridge creation process, the MAC address of the bridge was
  added to the FDB as an entry pointing towards the bridge device
  itself, but with no switchdev ports being part of the bridge yet, this
  local FDB entry would remain unknown to the switchdev hardware
  database.
- a VLAN/FDB/MDB was added to a bridge port that is a LAG interface,
  before any switchdev port joined that LAG, leading to the hardware
  database missing those entries.
- a switchdev port left a LAG that is a bridge port, while the LAG
  remained part of the bridge, and all FDB/MDB/VLAN entries remained
  installed in the hardware database of the switchdev port.

Also, since commit 0d2cfbd41c4a ("net: bridge: ignore switchdev events
for LAG ports which didn't request replay"), DSA introduced a method,
based on a const void *ctx, to ensure that two switchdev ports under the
same LAG that is a bridge port do not see the same MDB/VLAN entry being
replayed twice by the bridge, once for every bridge port that joins the
LAG.

With so many ordering corner cases being possible, it seems unreasonable
to expect a switchdev driver writer to get it right from the first try.
Therefore, now that DSA has experimented with the bridge replay helpers
for a little bit, we can move the code to the bridge driver where it is
more readily available to all switchdev drivers.

To convert the switchdev object replay helpers from "pull mode" (where
the driver asks for them) to a "push mode" (where the bridge offers
them
automatically), the biggest problem is that the bridge needs to be aware
when a switchdev port joins and leaves, even when the switchdev is only
indirectly a bridge port (for example when the bridge port is a LAG
upper of the switchdev).

Luckily, we already have a hook for that, in the form of the newly
introduced switchdev_bridge_port_offload() and
switchdev_bridge_port_unoffload() calls. These offer a natural place for
hooking the object addition and deletion replays.

Extend the above 2 functions with:
- pointers to the switchdev atomic notifier (for FDB replays) and the
  blocking notifier (for MDB and VLAN replays).
- the "const void *ctx" argument required for drivers to be able to
  disambiguate between which port is targeted, when multiple ports are
  lowers of the same LAG that is a bridge port. Most of the drivers pass
  NULL to this argument, except the ones that support LAG offload and have
  the proper context check already in place in the switchdev blocking
  notifier handler.

Also unexport the replay helpers, since nobody except the bridge calls
them directly now.

Note that:
(a) we abuse the terminology slightly, because FDB entries are not
    "switchdev objects", but we count them as objects nonetheless.
    With no direct way to prove it, I think they are not modeled as
    switchdev objects because those can only be installed by the bridge
    to the hardware (as opposed to FDB entries which can be propagated
    in the other direction too). This is merely an abuse of terms, FDB
    entries are replayed too, despite not being objects.
(b) the bridge does not attempt to sync port attributes to newly joined
    ports, just the countable stuff (the objects). The reason for this
    is simple: no universal and symmetric way to sync and unsync them is
    known. For example, VLAN filtering: what to do on unsync, disable or
    leave it enabled? Similarly, STP state, ageing timer, etc etc. What
    a switchdev port does when it becomes standalone again is not really
    up to the bridge's competence, and the driver should deal with it.
    On the other hand, replaying deletions of switchdev objects can be
    seen a matter of cleanup and therefore be treated by the bridge,
    hence this patch.

We make the replay helpers opt-in for drivers, because they might not
bring immediate benefits for them:

- nbp_vlan_init() is called _after_ netdev_master_upper_dev_link(),
  so br_vlan_replay() should not do anything for the new drivers on
  which we call it. The existing drivers where there was even a slight
  possibility for there to exist a VLAN on a bridge port before they
  join it are already guarded against this: mlxsw and prestera deny
  joining LAG interfaces that are members of a bridge.

- br_fdb_replay() should now notify of local FDB entries, but I patched
  all drivers except DSA to ignore these new entries in commit
  2c4eca3ef716 ("net: bridge: switchdev: include local flag in FDB
  notifications"). Driver authors can lift this restriction as they
  wish, and when they do, they can also opt into the FDB replay
  functionality.

- br_mdb_replay() should fix a real issue which is described in commit
  4f2673b3a2b6 ("net: bridge: add helper to replay port and host-joined
  mdb entries"). However most drivers do not offload the
  SWITCHDEV_OBJ_ID_HOST_MDB to see this issue: only cpsw and am65_cpsw
  offload this switchdev object, and I don't completely understand the
  way in which they offload this switchdev object anyway. So I'll leave
  it up to these drivers' respective maintainers to opt into
  br_mdb_replay().

So most of the drivers pass NULL notifier blocks for the replay helpers,
except:
- dpaa2-switch which was already acked/regression-tested with the
  helpers enabled (and there isn't much of a downside in having them)
- ocelot which already had replay logic in "pull" mode
- DSA which already had replay logic in "pull" mode

An important observation is that the drivers which don't currently
request bridge event replays don't even have the
switchdev_bridge_port_{offload,unoffload} calls placed in proper places
right now. This was done to avoid unnecessary rework for drivers which
might never even add support for this. For driver writers who wish to
add replay support, this can be used as a tentative placement guide:
https://patchwork.kernel.org/project/netdevbpf/patch/20210720134655.892334-11-vladimir.oltean
at nxp.com/

Cc: Vadym Kochan <vkochan at marvell.com>
Cc: Taras Chornyi <tchornyi at marvell.com>
Cc: Ioana Ciornei <ioana.ciornei at nxp.com>
Cc: Lars Povlsen <lars.povlsen at microchip.com>
Cc: Steen Hegelund <Steen.Hegelund at microchip.com>
Cc: UNGLinuxDriver at microchip.com
Cc: Claudiu Manoil <claudiu.manoil at nxp.com>
Cc: Alexandre Belloni <alexandre.belloni at bootlin.com>
Cc: Grygorii Strashko <grygorii.strashko at ti.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean at nxp.com>
Acked-by: Ioana Ciornei <ioana.ciornei at nxp.com> # dpaa2-switch
---
v2->v3: patch is new
v3->v4: passing the switchdev notifier blocks as argument to
        switchdev_bridge_port_offload()
v4->v5: fixed the reference to the proper br_mdb_replay() patch in the
        commit message
v5->v6:
- make the event replay optional
- opt out of replays for mlxsw, rocker, prestera, sparx5, cpsw,
  am65-cpsw

 .../ethernet/freescale/dpaa2/dpaa2-switch.c   | 12 ++-
 .../marvell/prestera/prestera_switchdev.c     |  7 +-
 .../mellanox/mlxsw/spectrum_switchdev.c       |  4 +-
 .../microchip/sparx5/sparx5_switchdev.c       |  5 +-
 drivers/net/ethernet/mscc/ocelot_net.c        | 45 ++++------
 drivers/net/ethernet/rocker/rocker_ofdpa.c    |  5 +-
 drivers/net/ethernet/ti/am65-cpsw-nuss.c      |  5 +-
 drivers/net/ethernet/ti/cpsw_new.c            |  5 +-
 include/linux/if_bridge.h                     | 54 ++++--------
 net/bridge/br_fdb.c                           |  1 -
 net/bridge/br_mdb.c                           |  1 -
 net/bridge/br_private.h                       | 25 ++++++
 net/bridge/br_switchdev.c                     | 75 ++++++++++++++++-
 net/bridge/br_vlan.c                          |  1 -
 net/dsa/dsa_priv.h                            |  6 +-
 net/dsa/port.c                                | 84 ++++---------------
 net/dsa/slave.c                               | 10 +--
 17 files changed, 182 insertions(+), 163 deletions(-)

diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
index 9b090da3e460..2138239facfd 100644
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch.c
@@ -1889,6 +1889,9 @@ static int dpaa2_switch_port_attr_set_event(struct
net_device *netdev,
 	return notifier_from_errno(err);
 }
 
+static struct notifier_block dpaa2_switch_port_switchdev_nb;
+static struct notifier_block dpaa2_switch_port_switchdev_blocking_nb;
+
 static int dpaa2_switch_port_bridge_join(struct net_device *netdev,
 					 struct net_device *upper_dev,
 					 struct netlink_ext_ack *extack)
@@ -1930,7 +1933,10 @@ static int dpaa2_switch_port_bridge_join(struct
net_device *netdev,
 	if (err)
 		goto err_egress_flood;
 
-	err = switchdev_bridge_port_offload(netdev, netdev, extack);
+	err = switchdev_bridge_port_offload(netdev, netdev, NULL,
+					    &dpaa2_switch_port_switchdev_nb,
+					    &dpaa2_switch_port_switchdev_blocking_nb,
+					    extack);
 	if (err)
 		goto err_switchdev_offload;
 
@@ -1964,7 +1970,9 @@ static int dpaa2_switch_port_restore_rxvlan(struct
net_device *vdev, int vid, vo
 
 static void dpaa2_switch_port_pre_bridge_leave(struct net_device *netdev)
 {
-	switchdev_bridge_port_unoffload(netdev);
+	switchdev_bridge_port_unoffload(netdev, NULL,
+					&dpaa2_switch_port_switchdev_nb,
+					&dpaa2_switch_port_switchdev_blocking_nb);
 }
 
 static int dpaa2_switch_port_bridge_leave(struct net_device *netdev)
diff --git a/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
b/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
index 8cf3fe3b7e58..7fe1287228e5 100644
--- a/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
+++ b/drivers/net/ethernet/marvell/prestera/prestera_switchdev.c
@@ -501,7 +501,8 @@ int prestera_bridge_port_join(struct net_device *br_dev,
 		goto err_brport_create;
 	}
 
-	err = switchdev_bridge_port_offload(br_port->dev, port->dev, extack);
+	err = switchdev_bridge_port_offload(br_port->dev, port->dev, NULL,
+					    NULL, NULL, extack);
 	if (err)
 		goto err_switchdev_offload;
 
@@ -515,7 +516,7 @@ int prestera_bridge_port_join(struct net_device *br_dev,
 	return 0;
 
 err_port_join:
-	switchdev_bridge_port_unoffload(br_port->dev);
+	switchdev_bridge_port_unoffload(br_port->dev, NULL, NULL, NULL);
 err_switchdev_offload:
 	prestera_bridge_port_put(br_port);
 err_brport_create:
@@ -591,7 +592,7 @@ void prestera_bridge_port_leave(struct net_device *br_dev,
 	else
 		prestera_bridge_1d_port_leave(br_port);
 
-	switchdev_bridge_port_unoffload(br_port->dev);
+	switchdev_bridge_port_unoffload(br_port->dev, NULL, NULL, NULL);
 
 	prestera_hw_port_learning_set(port, false);
 	prestera_hw_port_flood_set(port, BR_FLOOD | BR_MCAST_FLOOD, 0);
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
b/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
index c52317de1f35..0a53f1d8e7e1 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_switchdev.c
@@ -362,7 +362,7 @@ mlxsw_sp_bridge_port_create(struct mlxsw_sp_bridge_device
*bridge_device,
 	bridge_port->ref_count = 1;
 
 	err = switchdev_bridge_port_offload(brport_dev, mlxsw_sp_port->dev,
-					    extack);
+					    NULL, NULL, NULL, extack);
 	if (err)
 		goto err_switchdev_offload;
 
@@ -377,7 +377,7 @@ mlxsw_sp_bridge_port_create(struct mlxsw_sp_bridge_device
*bridge_device,
 static void
 mlxsw_sp_bridge_port_destroy(struct mlxsw_sp_bridge_port *bridge_port)
 {
-	switchdev_bridge_port_unoffload(bridge_port->dev);
+	switchdev_bridge_port_unoffload(bridge_port->dev, NULL, NULL, NULL);
 	list_del(&bridge_port->list);
 	WARN_ON(!list_empty(&bridge_port->vlans_list));
 	kfree(bridge_port);
diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
b/drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
index e4fb573563d0..807dc45cfae4 100644
--- a/drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
+++ b/drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.c
@@ -112,7 +112,8 @@ static int sparx5_port_bridge_join(struct sparx5_port *port,
 
 	set_bit(port->portno, sparx5->bridge_mask);
 
-	err = switchdev_bridge_port_offload(ndev, ndev, extack);
+	err = switchdev_bridge_port_offload(ndev, ndev, NULL, NULL, NULL,
+					    extack);
 	if (err)
 		goto err_switchdev_offload;
 
@@ -133,7 +134,7 @@ static void sparx5_port_bridge_leave(struct sparx5_port
*port,
 {
 	struct sparx5 *sparx5 = port->sparx5;
 
-	switchdev_bridge_port_unoffload(port->ndev);
+	switchdev_bridge_port_unoffload(port->ndev, NULL, NULL, NULL);
 
 	clear_bit(port->portno, sparx5->bridge_mask);
 	if (bitmap_empty(sparx5->bridge_mask, SPX5_PORTS))
diff --git a/drivers/net/ethernet/mscc/ocelot_net.c
b/drivers/net/ethernet/mscc/ocelot_net.c
index 76b7b9536bf7..3558ee8d9212 100644
--- a/drivers/net/ethernet/mscc/ocelot_net.c
+++ b/drivers/net/ethernet/mscc/ocelot_net.c
@@ -1154,38 +1154,19 @@ static int ocelot_switchdev_sync(struct ocelot *ocelot,
int port,
 				 struct net_device *bridge_dev,
 				 struct netlink_ext_ack *extack)
 {
-	struct ocelot_port *ocelot_port = ocelot->ports[port];
-	struct ocelot_port_private *priv;
 	clock_t ageing_time;
 	u8 stp_state;
-	int err;
-
-	priv = container_of(ocelot_port, struct ocelot_port_private, port);
 
 	ocelot_inherit_brport_flags(ocelot, port, brport_dev);
 
 	stp_state = br_port_get_stp_state(brport_dev);
 	ocelot_bridge_stp_state_set(ocelot, port, stp_state);
 
-	err = ocelot_port_vlan_filtering(ocelot, port,
-					 br_vlan_enabled(bridge_dev));
-	if (err)
-		return err;
-
 	ageing_time = br_get_ageing_time(bridge_dev);
 	ocelot_port_attr_ageing_set(ocelot, port, ageing_time);
 
-	err = br_mdb_replay(bridge_dev, brport_dev, priv, true,
-			    &ocelot_switchdev_blocking_nb, extack);
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
-	err = br_vlan_replay(bridge_dev, brport_dev, priv, true,
-			     &ocelot_switchdev_blocking_nb, extack);
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
-	return 0;
+	return ocelot_port_vlan_filtering(ocelot, port,
+					  br_vlan_enabled(bridge_dev));
 }
 
 static int ocelot_switchdev_unsync(struct ocelot *ocelot, int port)
@@ -1216,7 +1197,10 @@ static int ocelot_netdevice_bridge_join(struct net_device
*dev,
 
 	ocelot_port_bridge_join(ocelot, port, bridge);
 
-	err = switchdev_bridge_port_offload(brport_dev, dev, extack);
+	err = switchdev_bridge_port_offload(brport_dev, dev, priv,
+					    &ocelot_netdevice_nb,
+					    &ocelot_switchdev_blocking_nb,
+					    extack);
 	if (err)
 		goto err_switchdev_offload;
 
@@ -1227,15 +1211,22 @@ static int ocelot_netdevice_bridge_join(struct
net_device *dev,
 	return 0;
 
 err_switchdev_sync:
-	switchdev_bridge_port_unoffload(brport_dev);
+	switchdev_bridge_port_unoffload(brport_dev, priv,
+					&ocelot_netdevice_nb,
+					&ocelot_switchdev_blocking_nb);
 err_switchdev_offload:
 	ocelot_port_bridge_leave(ocelot, port, bridge);
 	return err;
 }
 
-static void ocelot_netdevice_pre_bridge_leave(struct net_device *brport_dev)
+static void ocelot_netdevice_pre_bridge_leave(struct net_device *dev,
+					      struct net_device *brport_dev)
 {
-	switchdev_bridge_port_unoffload(brport_dev);
+	struct ocelot_port_private *priv = netdev_priv(dev);
+
+	switchdev_bridge_port_unoffload(brport_dev, priv,
+					&ocelot_netdevice_nb,
+					&ocelot_switchdev_blocking_nb);
 }
 
 static int ocelot_netdevice_bridge_leave(struct net_device *dev,
@@ -1299,7 +1290,7 @@ static void ocelot_netdevice_pre_lag_leave(struct
net_device *dev,
 	if (!bridge_dev || !netif_is_bridge_master(bridge_dev))
 		return;
 
-	ocelot_netdevice_pre_bridge_leave(bond);
+	ocelot_netdevice_pre_bridge_leave(dev, bond);
 }
 
 static int ocelot_netdevice_lag_leave(struct net_device *dev,
@@ -1384,7 +1375,7 @@ ocelot_netdevice_prechangeupper(struct net_device *dev,
 				struct netdev_notifier_changeupper_info *info)
 {
 	if (netif_is_bridge_master(info->upper_dev) && !info->linking)
-		ocelot_netdevice_pre_bridge_leave(brport_dev);
+		ocelot_netdevice_pre_bridge_leave(dev, brport_dev);
 
 	if (netif_is_lag_master(info->upper_dev) && !info->linking)
 		ocelot_netdevice_pre_lag_leave(dev, info->upper_dev);
diff --git a/drivers/net/ethernet/rocker/rocker_ofdpa.c
b/drivers/net/ethernet/rocker/rocker_ofdpa.c
index 84dcaf8687a0..03df6a24d0ba 100644
--- a/drivers/net/ethernet/rocker/rocker_ofdpa.c
+++ b/drivers/net/ethernet/rocker/rocker_ofdpa.c
@@ -2598,7 +2598,8 @@ static int ofdpa_port_bridge_join(struct ofdpa_port
*ofdpa_port,
 	if (err)
 		return err;
 
-	return switchdev_bridge_port_offload(dev, dev, extack);
+	return switchdev_bridge_port_offload(dev, dev, NULL, NULL, NULL,
+					     extack);
 }
 
 static int ofdpa_port_bridge_leave(struct ofdpa_port *ofdpa_port)
@@ -2606,7 +2607,7 @@ static int ofdpa_port_bridge_leave(struct ofdpa_port
*ofdpa_port)
 	struct net_device *dev = ofdpa_port->dev;
 	int err;
 
-	switchdev_bridge_port_unoffload(dev);
+	switchdev_bridge_port_unoffload(dev, NULL, NULL, NULL);
 
 	err = ofdpa_port_vlan_del(ofdpa_port, OFDPA_UNTAGGED_VID, 0);
 	if (err)
diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
index 8b9596eb808e..b285606f963d 100644
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c
+++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c
@@ -2096,7 +2096,8 @@ static int am65_cpsw_netdevice_port_link(struct net_device
*ndev,
 			return -EOPNOTSUPP;
 	}
 
-	err = switchdev_bridge_port_offload(ndev, ndev, extack);
+	err = switchdev_bridge_port_offload(ndev, ndev, NULL, NULL, NULL,
+					    extack);
 	if (err)
 		return err;
 
@@ -2112,7 +2113,7 @@ static void am65_cpsw_netdevice_port_unlink(struct
net_device *ndev)
 	struct am65_cpsw_common *common = am65_ndev_to_common(ndev);
 	struct am65_cpsw_ndev_priv *priv = am65_ndev_to_priv(ndev);
 
-	switchdev_bridge_port_unoffload(ndev);
+	switchdev_bridge_port_unoffload(ndev, NULL, NULL, NULL);
 
 	common->br_members &= ~BIT(priv->port->port_id);
 
diff --git a/drivers/net/ethernet/ti/cpsw_new.c
b/drivers/net/ethernet/ti/cpsw_new.c
index bf9cadfb11b5..31030f73840d 100644
--- a/drivers/net/ethernet/ti/cpsw_new.c
+++ b/drivers/net/ethernet/ti/cpsw_new.c
@@ -1517,7 +1517,8 @@ static int cpsw_netdevice_port_link(struct net_device
*ndev,
 			return -EOPNOTSUPP;
 	}
 
-	err = switchdev_bridge_port_offload(ndev, ndev, extack);
+	err = switchdev_bridge_port_offload(ndev, ndev, NULL, NULL, NULL,
+					    extack);
 	if (err)
 		return err;
 
@@ -1533,7 +1534,7 @@ static void cpsw_netdevice_port_unlink(struct net_device
*ndev)
 	struct cpsw_priv *priv = netdev_priv(ndev);
 	struct cpsw_common *cpsw = priv->cpsw;
 
-	switchdev_bridge_port_unoffload(ndev);
+	switchdev_bridge_port_unoffload(ndev, NULL, NULL, NULL);
 
 	cpsw->br_members &= ~BIT(priv->emac_port);
 
diff --git a/include/linux/if_bridge.h b/include/linux/if_bridge.h
index ce413eca527e..bbf680093823 100644
--- a/include/linux/if_bridge.h
+++ b/include/linux/if_bridge.h
@@ -70,9 +70,6 @@ bool br_multicast_has_querier_adjacent(struct net_device *dev,
int proto);
 bool br_multicast_has_router_adjacent(struct net_device *dev, int proto);
 bool br_multicast_enabled(const struct net_device *dev);
 bool br_multicast_router(const struct net_device *dev);
-int br_mdb_replay(struct net_device *br_dev, struct net_device *dev,
-		  const void *ctx, bool adding, struct notifier_block *nb,
-		  struct netlink_ext_ack *extack);
 #else
 static inline int br_multicast_list_adjacent(struct net_device *dev,
 					     struct list_head *br_ip_list)
@@ -104,13 +101,6 @@ static inline bool br_multicast_router(const struct
net_device *dev)
 {
 	return false;
 }
-static inline int br_mdb_replay(const struct net_device *br_dev,
-				const struct net_device *dev, const void *ctx,
-				bool adding, struct notifier_block *nb,
-				struct netlink_ext_ack *extack)
-{
-	return -EOPNOTSUPP;
-}
 #endif
 
 #if IS_ENABLED(CONFIG_BRIDGE) &&
IS_ENABLED(CONFIG_BRIDGE_VLAN_FILTERING)
@@ -120,9 +110,6 @@ int br_vlan_get_pvid_rcu(const struct net_device *dev, u16
*p_pvid);
 int br_vlan_get_proto(const struct net_device *dev, u16 *p_proto);
 int br_vlan_get_info(const struct net_device *dev, u16 vid,
 		     struct bridge_vlan_info *p_vinfo);
-int br_vlan_replay(struct net_device *br_dev, struct net_device *dev,
-		   const void *ctx, bool adding, struct notifier_block *nb,
-		   struct netlink_ext_ack *extack);
 #else
 static inline bool br_vlan_enabled(const struct net_device *dev)
 {
@@ -149,14 +136,6 @@ static inline int br_vlan_get_info(const struct net_device
*dev, u16 vid,
 {
 	return -EINVAL;
 }
-
-static inline int br_vlan_replay(struct net_device *br_dev,
-				 struct net_device *dev, const void *ctx,
-				 bool adding, struct notifier_block *nb,
-				 struct netlink_ext_ack *extack)
-{
-	return -EOPNOTSUPP;
-}
 #endif
 
 #if IS_ENABLED(CONFIG_BRIDGE)
@@ -167,8 +146,6 @@ void br_fdb_clear_offload(const struct net_device *dev, u16
vid);
 bool br_port_flag_is_set(const struct net_device *dev, unsigned long flag);
 u8 br_port_get_stp_state(const struct net_device *dev);
 clock_t br_get_ageing_time(const struct net_device *br_dev);
-int br_fdb_replay(const struct net_device *br_dev, const struct net_device
*dev,
-		  const void *ctx, bool adding, struct notifier_block *nb);
 #else
 static inline struct net_device *
 br_fdb_find_port(const struct net_device *br_dev,
@@ -197,32 +174,37 @@ static inline clock_t br_get_ageing_time(const struct
net_device *br_dev)
 {
 	return 0;
 }
-
-static inline int br_fdb_replay(const struct net_device *br_dev,
-				const struct net_device *dev, const void *ctx,
-				bool adding, struct notifier_block *nb)
-{
-	return -EOPNOTSUPP;
-}
 #endif
 
 #if IS_ENABLED(CONFIG_BRIDGE) && IS_ENABLED(CONFIG_NET_SWITCHDEV)
 
 int switchdev_bridge_port_offload(struct net_device *brport_dev,
-				  struct net_device *dev,
+				  struct net_device *dev, const void *ctx,
+				  struct notifier_block *atomic_nb,
+				  struct notifier_block *blocking_nb,
 				  struct netlink_ext_ack *extack);
-void switchdev_bridge_port_unoffload(struct net_device *brport_dev);
+void switchdev_bridge_port_unoffload(struct net_device *brport_dev,
+				     const void *ctx,
+				     struct notifier_block *atomic_nb,
+				     struct notifier_block *blocking_nb);
 
 #else
 
-static inline int switchdev_bridge_port_offload(struct net_device *brport_dev,
-						struct net_device *dev,
-						struct netlink_ext_ack *extack)
+static inline int
+switchdev_bridge_port_offload(struct net_device *brport_dev,
+			      struct net_device *dev, const void *ctx,
+			      struct notifier_block *atomic_nb,
+			      struct notifier_block *blocking_nb,
+			      struct netlink_ext_ack *extack)
 {
 	return -EINVAL;
 }
 
-static inline void switchdev_bridge_port_unoffload(struct net_device
*brport_dev)
+static inline void
+switchdev_bridge_port_unoffload(struct net_device *brport_dev,
+				const void *ctx,
+				struct notifier_block *atomic_nb,
+				struct notifier_block *blocking_nb)
 {
 }
 #endif
diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
index 47f190b6bfa3..7747442e6572 100644
--- a/net/bridge/br_fdb.c
+++ b/net/bridge/br_fdb.c
@@ -795,7 +795,6 @@ int br_fdb_replay(const struct net_device *br_dev, const
struct net_device *dev,
 
 	return err;
 }
-EXPORT_SYMBOL_GPL(br_fdb_replay);
 
 static void fdb_notify(struct net_bridge *br,
 		       const struct net_bridge_fdb_entry *fdb, int type,
diff --git a/net/bridge/br_mdb.c b/net/bridge/br_mdb.c
index 09358c475787..b8ddd6b6c7fe 100644
--- a/net/bridge/br_mdb.c
+++ b/net/bridge/br_mdb.c
@@ -689,7 +689,6 @@ int br_mdb_replay(struct net_device *br_dev, struct
net_device *dev,
 
 	return err;
 }
-EXPORT_SYMBOL_GPL(br_mdb_replay);
 
 static void br_mdb_switchdev_host_port(struct net_device *dev,
 				       struct net_device *lower_dev,
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index 8d2e4d807808..978405cc1a91 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -769,6 +769,8 @@ int br_fdb_external_learn_del(struct net_bridge *br, struct
net_bridge_port *p,
 			      bool swdev_notify);
 void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
 			  const unsigned char *addr, u16 vid, bool offloaded);
+int br_fdb_replay(const struct net_device *br_dev, const struct net_device
*dev,
+		  const void *ctx, bool adding, struct notifier_block *nb);
 
 /* br_forward.c */
 enum br_pkt_type {
@@ -928,6 +930,10 @@ int br_multicast_toggle_vlan_snooping(struct net_bridge
*br, bool on,
 				      struct netlink_ext_ack *extack);
 bool br_multicast_toggle_global_vlan(struct net_bridge_vlan *vlan, bool on);
 
+int br_mdb_replay(struct net_device *br_dev, struct net_device *dev,
+		  const void *ctx, bool adding, struct notifier_block *nb,
+		  struct netlink_ext_ack *extack);
+
 static inline bool br_group_is_l2(const struct br_ip *group)
 {
 	return group->proto == 0;
@@ -1306,6 +1312,14 @@ static inline bool br_multicast_toggle_global_vlan(struct
net_bridge_vlan *vlan,
 {
 	return false;
 }
+
+static inline int br_mdb_replay(struct net_device *br_dev,
+				struct net_device *dev, const void *ctx,
+				bool adding, struct notifier_block *nb,
+				struct netlink_ext_ack *extack)
+{
+	return -EOPNOTSUPP;
+}
 #endif
 
 /* br_vlan.c */
@@ -1357,6 +1371,9 @@ void br_vlan_notify(const struct net_bridge *br,
 		    const struct net_bridge_port *p,
 		    u16 vid, u16 vid_range,
 		    int cmd);
+int br_vlan_replay(struct net_device *br_dev, struct net_device *dev,
+		   const void *ctx, bool adding, struct notifier_block *nb,
+		   struct netlink_ext_ack *extack);
 bool br_vlan_can_enter_range(const struct net_bridge_vlan *v_curr,
 			     const struct net_bridge_vlan *range_end);
 
@@ -1602,6 +1619,14 @@ static inline bool br_vlan_can_enter_range(const struct
net_bridge_vlan *v_curr,
 {
 	return true;
 }
+
+static inline int br_vlan_replay(struct net_device *br_dev,
+				 struct net_device *dev, const void *ctx,
+				 bool adding, struct notifier_block *nb,
+				 struct netlink_ext_ack *extack)
+{
+	return -EOPNOTSUPP;
+}
 #endif
 
 /* br_vlan_options.c */
diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
index 39f0787fde01..6bfff28ede23 100644
--- a/net/bridge/br_switchdev.c
+++ b/net/bridge/br_switchdev.c
@@ -206,11 +206,62 @@ static void nbp_switchdev_del(struct net_bridge_port *p)
 		nbp_switchdev_hwdom_put(p);
 }
 
+static int nbp_switchdev_sync_objs(struct net_bridge_port *p, const void *ctx,
+				   struct notifier_block *atomic_nb,
+				   struct notifier_block *blocking_nb,
+				   struct netlink_ext_ack *extack)
+{
+	struct net_device *br_dev = p->br->dev;
+	struct net_device *dev = p->dev;
+	int err;
+
+	err = br_vlan_replay(br_dev, dev, ctx, true, blocking_nb, extack);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = br_mdb_replay(br_dev, dev, ctx, true, blocking_nb, extack);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	/* Forwarding and termination FDB entries on the port */
+	err = br_fdb_replay(br_dev, dev, ctx, true, atomic_nb);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	/* Termination FDB entries on the bridge itself */
+	err = br_fdb_replay(br_dev, br_dev, ctx, true, atomic_nb);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	return 0;
+}
+
+static void nbp_switchdev_unsync_objs(struct net_bridge_port *p,
+				      const void *ctx,
+				      struct notifier_block *atomic_nb,
+				      struct notifier_block *blocking_nb)
+{
+	struct net_device *br_dev = p->br->dev;
+	struct net_device *dev = p->dev;
+
+	br_vlan_replay(br_dev, dev, ctx, false, blocking_nb, NULL);
+
+	br_mdb_replay(br_dev, dev, ctx, false, blocking_nb, NULL);
+
+	/* Forwarding and termination FDB entries on the port */
+	br_fdb_replay(br_dev, dev, ctx, false, atomic_nb);
+
+	/* Termination FDB entries on the bridge itself */
+	br_fdb_replay(br_dev, br_dev, ctx, false, atomic_nb);
+}
+
 /* Let the bridge know that this port is offloaded, so that it can assign a
  * switchdev hardware domain to it.
  */
 int switchdev_bridge_port_offload(struct net_device *brport_dev,
-				  struct net_device *dev,
+				  struct net_device *dev, const void *ctx,
+				  struct notifier_block *atomic_nb,
+				  struct notifier_block *blocking_nb,
 				  struct netlink_ext_ack *extack)
 {
 	struct netdev_phys_item_id ppid;
@@ -227,11 +278,27 @@ int switchdev_bridge_port_offload(struct net_device
*brport_dev,
 	if (err)
 		return err;
 
-	return nbp_switchdev_add(p, ppid, extack);
+	err = nbp_switchdev_add(p, ppid, extack);
+	if (err)
+		return err;
+
+	err = nbp_switchdev_sync_objs(p, ctx, atomic_nb, blocking_nb, extack);
+	if (err)
+		goto out_switchdev_del;
+
+	return 0;
+
+out_switchdev_del:
+	nbp_switchdev_del(p);
+
+	return err;
 }
 EXPORT_SYMBOL_GPL(switchdev_bridge_port_offload);
 
-void switchdev_bridge_port_unoffload(struct net_device *brport_dev)
+void switchdev_bridge_port_unoffload(struct net_device *brport_dev,
+				     const void *ctx,
+				     struct notifier_block *atomic_nb,
+				     struct notifier_block *blocking_nb)
 {
 	struct net_bridge_port *p;
 
@@ -241,6 +308,8 @@ void switchdev_bridge_port_unoffload(struct net_device
*brport_dev)
 	if (!p)
 		return;
 
+	nbp_switchdev_unsync_objs(p, ctx, atomic_nb, blocking_nb);
+
 	nbp_switchdev_del(p);
 }
 EXPORT_SYMBOL_GPL(switchdev_bridge_port_unoffload);
diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c
index 45ef07f682f1..382ab992badf 100644
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -1905,7 +1905,6 @@ int br_vlan_replay(struct net_device *br_dev, struct
net_device *dev,
 
 	return err;
 }
-EXPORT_SYMBOL_GPL(br_vlan_replay);
 
 /* check if v_curr can enter a range ending in range_end */
 bool br_vlan_can_enter_range(const struct net_bridge_vlan *v_curr,
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 4d3ab9e6183a..78c70f5bdab5 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -204,16 +204,14 @@ void dsa_port_disable_rt(struct dsa_port *dp);
 void dsa_port_disable(struct dsa_port *dp);
 int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br,
 			 struct netlink_ext_ack *extack);
-int dsa_port_pre_bridge_leave(struct dsa_port *dp, struct net_device *br,
-			      struct netlink_ext_ack *extack);
+void dsa_port_pre_bridge_leave(struct dsa_port *dp, struct net_device *br);
 void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br);
 int dsa_port_lag_change(struct dsa_port *dp,
 			struct netdev_lag_lower_state_info *linfo);
 int dsa_port_lag_join(struct dsa_port *dp, struct net_device *lag_dev,
 		      struct netdev_lag_upper_info *uinfo,
 		      struct netlink_ext_ack *extack);
-int dsa_port_pre_lag_leave(struct dsa_port *dp, struct net_device *lag_dev,
-			   struct netlink_ext_ack *extack);
+void dsa_port_pre_lag_leave(struct dsa_port *dp, struct net_device *lag_dev);
 void dsa_port_lag_leave(struct dsa_port *dp, struct net_device *lag_dev);
 int dsa_port_vlan_filtering(struct dsa_port *dp, bool vlan_filtering,
 			    struct netlink_ext_ack *extack);
diff --git a/net/dsa/port.c b/net/dsa/port.c
index 7accda066149..d81c283b7358 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -167,8 +167,8 @@ static void dsa_port_clear_brport_flags(struct dsa_port *dp)
 	}
 }
 
-static int dsa_port_switchdev_sync(struct dsa_port *dp,
-				   struct netlink_ext_ack *extack)
+static int dsa_port_switchdev_sync_attrs(struct dsa_port *dp,
+					 struct netlink_ext_ack *extack)
 {
 	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
 	struct net_device *br = dp->bridge_dev;
@@ -194,59 +194,6 @@ static int dsa_port_switchdev_sync(struct dsa_port *dp,
 	if (err && err != -EOPNOTSUPP)
 		return err;
 
-	err = br_mdb_replay(br, brport_dev, dp, true,
-			    &dsa_slave_switchdev_blocking_notifier, extack);
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
-	/* Forwarding and termination FDB entries on the port */
-	err = br_fdb_replay(br, brport_dev, dp, true,
-			    &dsa_slave_switchdev_notifier);
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
-	/* Termination FDB entries on the bridge itself */
-	err = br_fdb_replay(br, br, dp, true, &dsa_slave_switchdev_notifier);
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
-	err = br_vlan_replay(br, brport_dev, dp, true,
-			     &dsa_slave_switchdev_blocking_notifier, extack);
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
-	return 0;
-}
-
-static int dsa_port_switchdev_unsync_objs(struct dsa_port *dp,
-					  struct net_device *br,
-					  struct netlink_ext_ack *extack)
-{
-	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
-	int err;
-
-	/* Delete the switchdev objects left on this port */
-	err = br_mdb_replay(br, brport_dev, dp, false,
-			    &dsa_slave_switchdev_blocking_notifier, extack);
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
-	/* Forwarding and termination FDB entries on the port */
-	err = br_fdb_replay(br, brport_dev, dp, false,
-			    &dsa_slave_switchdev_notifier);
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
-	/* Termination FDB entries on the bridge itself */
-	err = br_fdb_replay(br, br, dp, false, &dsa_slave_switchdev_notifier);
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
-	err = br_vlan_replay(br, brport_dev, dp, false,
-			     &dsa_slave_switchdev_blocking_notifier, extack);
-	if (err && err != -EOPNOTSUPP)
-		return err;
-
 	return 0;
 }
 
@@ -307,18 +254,23 @@ int dsa_port_bridge_join(struct dsa_port *dp, struct
net_device *br,
 	if (err)
 		goto out_rollback;
 
-	err = switchdev_bridge_port_offload(brport_dev, dev, extack);
+	err = switchdev_bridge_port_offload(brport_dev, dev, dp,
+					    &dsa_slave_switchdev_notifier,
+					    &dsa_slave_switchdev_blocking_notifier,
+					    extack);
 	if (err)
 		goto out_rollback_unbridge;
 
-	err = dsa_port_switchdev_sync(dp, extack);
+	err = dsa_port_switchdev_sync_attrs(dp, extack);
 	if (err)
 		goto out_rollback_unoffload;
 
 	return 0;
 
 out_rollback_unoffload:
-	switchdev_bridge_port_unoffload(brport_dev);
+	switchdev_bridge_port_unoffload(brport_dev, dp,
+					&dsa_slave_switchdev_notifier,
+					&dsa_slave_switchdev_blocking_notifier);
 out_rollback_unbridge:
 	dsa_broadcast(DSA_NOTIFIER_BRIDGE_LEAVE, &info);
 out_rollback:
@@ -326,14 +278,13 @@ int dsa_port_bridge_join(struct dsa_port *dp, struct
net_device *br,
 	return err;
 }
 
-int dsa_port_pre_bridge_leave(struct dsa_port *dp, struct net_device *br,
-			      struct netlink_ext_ack *extack)
+void dsa_port_pre_bridge_leave(struct dsa_port *dp, struct net_device *br)
 {
 	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
 
-	switchdev_bridge_port_unoffload(brport_dev);
-
-	return dsa_port_switchdev_unsync_objs(dp, br, extack);
+	switchdev_bridge_port_unoffload(brport_dev, dp,
+					&dsa_slave_switchdev_notifier,
+					&dsa_slave_switchdev_blocking_notifier);
 }
 
 void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br)
@@ -423,13 +374,10 @@ int dsa_port_lag_join(struct dsa_port *dp, struct
net_device *lag,
 	return err;
 }
 
-int dsa_port_pre_lag_leave(struct dsa_port *dp, struct net_device *lag,
-			   struct netlink_ext_ack *extack)
+void dsa_port_pre_lag_leave(struct dsa_port *dp, struct net_device *lag)
 {
 	if (dp->bridge_dev)
-		return dsa_port_pre_bridge_leave(dp, dp->bridge_dev, extack);
-
-	return 0;
+		dsa_port_pre_bridge_leave(dp, dp->bridge_dev);
 }
 
 void dsa_port_lag_leave(struct dsa_port *dp, struct net_device *lag)
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 22ce11cd770e..8105f642572b 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -2052,20 +2052,16 @@ static int dsa_slave_prechangeupper(struct net_device
*dev,
 				    struct netdev_notifier_changeupper_info *info)
 {
 	struct dsa_port *dp = dsa_slave_to_port(dev);
-	struct netlink_ext_ack *extack;
-	int err = 0;
-
-	extack = netdev_notifier_info_to_extack(&info->info);
 
 	if (netif_is_bridge_master(info->upper_dev) && !info->linking)
-		err = dsa_port_pre_bridge_leave(dp, info->upper_dev, extack);
+		dsa_port_pre_bridge_leave(dp, info->upper_dev);
 	else if (netif_is_lag_master(info->upper_dev) && !info->linking)
-		err = dsa_port_pre_lag_leave(dp, info->upper_dev, extack);
+		dsa_port_pre_lag_leave(dp, info->upper_dev);
 	/* dsa_port_pre_hsr_leave is not yet necessary since hsr cannot be
 	 * meaningfully enslaved to a bridge yet
 	 */
 
-	return notifier_from_errno(err);
+	return NOTIFY_DONE;
 }
 
 static int
-- 
2.25.1

Hello:

This series was applied to netdev/net-next.git (refs/heads/master):

On Wed, 21 Jul 2021 19:23:56 +0300 you wrote:
> This series introduces an explicit API through which switchdev drivers
> mark a bridge port as offloaded or not:
> - switchdev_bridge_port_offload()
> - switchdev_bridge_port_unoffload()
> 
> Currently, the bridge assumes that a port is offloaded if
> dev_get_port_parent_id(dev, &ppid, recurse=true) returns something, but
> that is just an assumption that breaks some use cases (like a
> non-offloaded LAG interface on top of a switchdev port, bridged with
> other switchdev ports).
> 
> [...]
Here is the summary with links:
  - [v6,net-next,1/7] net: dpaa2-switch: use extack in
dpaa2_switch_port_bridge_join
    https://git.kernel.org/netdev/net-next/c/123338d7d41e
  - [v6,net-next,2/7] net: dpaa2-switch: refactor prechangeupper sanity checks
    https://git.kernel.org/netdev/net-next/c/45035febc495
  - [v6,net-next,3/7] net: bridge: disambiguate offload_fwd_mark
    https://git.kernel.org/netdev/net-next/c/f7cf972f9375
  - [v6,net-next,4/7] net: bridge: switchdev: recycle unused hwdoms
    https://git.kernel.org/netdev/net-next/c/8582661048eb
  - [v6,net-next,5/7] net: bridge: switchdev: let drivers inform which bridge
ports are offloaded
    https://git.kernel.org/netdev/net-next/c/2f5dc00f7a3e
  - [v6,net-next,6/7] net: bridge: guard the switchdev replay helpers against a
NULL notifier block
    https://git.kernel.org/netdev/net-next/c/7105b50b7eec
  - [v6,net-next,7/7] net: bridge: move the switchdev object replay helpers to
"push" mode
    https://git.kernel.org/netdev/net-next/c/4e51bf44a03a

You are awesome, thank you!
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