Introduce a new netlink attribute 'ad_actor_port_prio' to allow setting
the LACP actor port priority on a per-slave basis. This extends the
existing bonding infrastructure to support more granular control over
LACP negotiations.

The priority value is embedded in LACPDU packets and will be used by
subsequent patches to influence aggregator selection policies.

Signed-off-by: Hangbin Liu <redacted>
---
 Documentation/networking/bonding.rst |  9 +++++++
 drivers/net/bonding/bond_3ad.c       |  2 ++
 drivers/net/bonding/bond_netlink.c   | 16 +++++++++++++
 drivers/net/bonding/bond_options.c   | 36 ++++++++++++++++++++++++++++
 include/net/bond_3ad.h               |  1 +
 include/net/bond_options.h           |  1 +
 include/uapi/linux/if_link.h         |  1 +
 7 files changed, 66 insertions(+)

diff --git a/Documentation/networking/bonding.rst b/Documentation/networking/bonding.rst
index f8f5766703d4..874d8a4681ec 100644
--- a/Documentation/networking/bonding.rst
+++ b/Documentation/networking/bonding.rst

@@ -193,6 +193,15 @@ ad_actor_sys_prio
 	This parameter has effect only in 802.3ad mode and is available through
 	SysFs interface.
 
+ad_actor_port_prio
+
+	In an AD system, this specifies the port priority. The allowed range
+	is 1 - 65535. If the value is not specified, it takes 255 as the
+	default value.
+
+	This parameter has effect only in 802.3ad mode and is available through
+	netlink interface.
+
 ad_actor_system
 
 	In an AD system, this specifies the mac-address for the actor in

diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index 2fca8e84ab10..19b389b81600 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c

@@ -436,6 +436,7 @@ static void __ad_actor_update_port(struct port *port)
 
 	port->actor_system = BOND_AD_INFO(bond).system.sys_mac_addr;
 	port->actor_system_priority = BOND_AD_INFO(bond).system.sys_priority;
+	port->actor_port_priority = SLAVE_AD_INFO(port->slave)->port_priority;
 }
 
 /* Conversions */

@@ -2211,6 +2212,7 @@ void bond_3ad_bind_slave(struct slave *slave)
 		port->actor_admin_port_key = bond->params.ad_user_port_key << 6;
 		ad_update_actor_keys(port, false);
 		/* actor system is the bond's system */
+		SLAVE_AD_INFO(slave)->port_priority = port->actor_port_priority;

 		__ad_actor_update_port(port);
 		/* tx timer(to verify that no more than MAX_TX_IN_SECOND
 		 * lacpdu's are sent in one second)

diff --git a/drivers/net/bonding/bond_netlink.c b/drivers/net/bonding/bond_netlink.c
index 57fff2421f1b..3a37298583ed 100644
--- a/drivers/net/bonding/bond_netlink.c
+++ b/drivers/net/bonding/bond_netlink.c

@@ -28,6 +28,7 @@ static size_t bond_get_slave_size(const struct net_device *bond_dev,
 		nla_total_size(sizeof(u8)) +	/* IFLA_BOND_SLAVE_AD_ACTOR_OPER_PORT_STATE */
 		nla_total_size(sizeof(u16)) +	/* IFLA_BOND_SLAVE_AD_PARTNER_OPER_PORT_STATE */
 		nla_total_size(sizeof(s32)) +	/* IFLA_BOND_SLAVE_PRIO */
+		nla_total_size(sizeof(u16)) +	/* IFLA_BOND_SLAVE_AD_ACTOR_PORT_PRIO */
 		0;
 }
 

@@ -77,6 +78,10 @@ static int bond_fill_slave_info(struct sk_buff *skb,
 					ad_port->partner_oper.port_state))
 				goto nla_put_failure;
 		}
+
+		if (nla_put_u16(skb, IFLA_BOND_SLAVE_AD_ACTOR_PORT_PRIO,
+				SLAVE_AD_INFO(slave)->port_priority))
+			goto nla_put_failure;