在 2024/7/1 20:58, Konstantin Taranov 写道:
From: Konstantin Taranov <kotaranov@xxxxxxxxxxxxx>
Add helper to get a master netdevice for a given port.
When mana is used with netvsc, the VF netdev is controlled
by an upper netvsc device. In a baremetal case, the VF
netdev is the master device.
Signed-off-by: Konstantin Taranov <kotaranov@xxxxxxxxxxxxx>
---
drivers/net/ethernet/microsoft/mana/mana_en.c | 18 ++++++++++++++++++
include/net/mana/mana.h | 2 ++
2 files changed, 20 insertions(+)
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index d087cf9..b893339 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -2948,3 +2948,21 @@ out:
gd->gdma_context = NULL;
kfree(ac);
}
+
+/* the caller should hold rcu_read_lock */
+struct net_device *mana_get_master_netdev_rcu(struct mana_context *ac, u32 port_index)
+{
+ struct net_device *ndev;
From the comments, this function requires rcu_read_lock. Can the
following be added in this function?
RCU_LOCKDEP_WARN(!rcu_read_lock_held(), "no rcu read lock held");
If rcu_read_lock is not held, this function will notify the caller.
This can explicitly ensure that rcu_read_lock should be held before this
fuction is called.
Best Regards,
Zhu Yanjun
+
+ if (port_index >= ac->num_ports)
+ return NULL;
+
+ /* When mana is used in netvsc, the upper netdevice should be returned. */
+ if (ac->ports[port_index]->flags & IFF_SLAVE)
+ ndev = netdev_master_upper_dev_get_rcu(ac->ports[port_index]);
+ else
+ ndev = ac->ports[port_index];
+
+ return ndev;
+}
+EXPORT_SYMBOL_NS(mana_get_master_netdev_rcu, NET_MANA);
diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
index 46f741e..2d3625c 100644
--- a/include/net/mana/mana.h
+++ b/include/net/mana/mana.h
@@ -797,4 +797,6 @@ void mana_destroy_wq_obj(struct mana_port_context *apc, u32 wq_type,
int mana_cfg_vport(struct mana_port_context *apc, u32 protection_dom_id,
u32 doorbell_pg_id);
void mana_uncfg_vport(struct mana_port_context *apc);
+
+struct net_device *mana_get_master_netdev_rcu(struct mana_context *ac, u32 port_index);
#endif /* _MANA_H */
