[patch rdma-next v3 1/2] net: mana: Change the function signature of mana_get_primary_netdev_rcu

[longli]

From: Long Li <lon...@microsoft.com>

Change mana_get_primary_netdev_rcu() to mana_get_primary_netdev(), and
return the ndev with refcount held. The caller is responsible for dropping
the refcount by calling dev_put().

Signed-off-by: Long Li <lon...@microsoft.com>
---
 drivers/infiniband/hw/mana/device.c           |  7 +++----
 drivers/net/ethernet/microsoft/mana/mana_en.c | 11 +++++++----
 include/net/mana/mana.h                       |  2 +-
 3 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/drivers/infiniband/hw/mana/device.c 
b/drivers/infiniband/hw/mana/device.c
index 3416a85f8738..afe3d8d20b3b 100644
--- a/drivers/infiniband/hw/mana/device.c
+++ b/drivers/infiniband/hw/mana/device.c
@@ -84,10 +84,8 @@ static int mana_ib_probe(struct auxiliary_device *adev,
        dev->ib_dev.num_comp_vectors = mdev->gdma_context->max_num_queues;
        dev->ib_dev.dev.parent = mdev->gdma_context->dev;
 
-       rcu_read_lock(); /* required to get primary netdev */
-       ndev = mana_get_primary_netdev_rcu(mc, 0);
+       ndev = mana_get_primary_netdev(mc, 0);
        if (!ndev) {
-               rcu_read_unlock();
                ret = -ENODEV;
                ibdev_err(&dev->ib_dev, "Failed to get netdev for IB port 1");
                goto free_ib_device;
@@ -95,7 +93,8 @@ static int mana_ib_probe(struct auxiliary_device *adev,
        ether_addr_copy(mac_addr, ndev->dev_addr);
        addrconf_addr_eui48((u8 *)&dev->ib_dev.node_guid, ndev->dev_addr);
        ret = ib_device_set_netdev(&dev->ib_dev, ndev, 1);
-       rcu_read_unlock();
+       /* mana_get_primary_netdev() returns ndev with refcount held */
+       dev_put(ndev);
        if (ret) {
                ibdev_err(&dev->ib_dev, "Failed to set ib netdev, ret %d", ret);
                goto free_ib_device;
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c 
b/drivers/net/ethernet/microsoft/mana/mana_en.c
index aa1e47233fe5..cfa664d5a137 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -3131,21 +3131,24 @@ void mana_remove(struct gdma_dev *gd, bool suspending)
        kfree(ac);
 }
 
-struct net_device *mana_get_primary_netdev_rcu(struct mana_context *ac, u32 
port_index)
+struct net_device *mana_get_primary_netdev(struct mana_context *ac, u32 
port_index)
 {
        struct net_device *ndev;
 
-       RCU_LOCKDEP_WARN(!rcu_read_lock_held(),
-                        "Taking primary netdev without holding the RCU read 
lock");
        if (port_index >= ac->num_ports)
                return NULL;
 
+       rcu_read_lock();
+
        /* 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];
 
+       dev_hold(ndev);
+       rcu_read_unlock();
+
        return ndev;
 }
-EXPORT_SYMBOL_NS(mana_get_primary_netdev_rcu, "NET_MANA");
+EXPORT_SYMBOL_NS(mana_get_primary_netdev, "NET_MANA");
diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
index 0d00b24eacaf..770359ce7d3b 100644
--- a/include/net/mana/mana.h
+++ b/include/net/mana/mana.h
@@ -827,5 +827,5 @@ 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_primary_netdev_rcu(struct mana_context *ac, u32 
port_index);
+struct net_device *mana_get_primary_netdev(struct mana_context *ac, u32 
port_index);
 #endif /* _MANA_H */
-- 
2.34.1