[SRU][N:linux-azure][PATCH 1/3] RDMA/mana_ib: Set correct device into ib

[John Cabaj]

From: Konstantin Taranov <kotaranov at microsoft.com>

BugLink: https://bugs.launchpad.net/bugs/2119572

Add mana_get_primary_netdev_rcu helper to get a primary
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
primary device.

Use the mana_get_primary_netdev_rcu() helper in the mana_ib
to get the correct device for querying network states.

Fixes: 8b184e4f1c32 ("RDMA/mana_ib: Enable RoCE on port 1")
Signed-off-by: Konstantin Taranov <kotaranov at microsoft.com>
Link: https://lore.kernel.org/r/1720705077-322-1-git-send-email-kotaranov@linux.microsoft.com
Reviewed-by: Long Li <longli at microsoft.com>
Reviewed-by: Zhu Yanjun <yanjun.zhu at linux.dev>
Signed-off-by: Leon Romanovsky <leon at kernel.org>
(backported from commit 1df03a4b44146c4f720d793915747272c7773a3e)
[john-cabaj: not including context from 8859f009ace2:
"RDMA/mana_ib: Configure mac address in RNIC" as it's not
relevant to this commit]
Signed-off-by: John Cabaj <john.cabaj at canonical.com>
---
 drivers/infiniband/hw/mana/device.c           | 12 ++++++------
 drivers/net/ethernet/microsoft/mana/mana_en.c | 19 +++++++++++++++++++
 include/net/mana/mana.h                       |  2 ++
 3 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/drivers/infiniband/hw/mana/device.c b/drivers/infiniband/hw/mana/device.c
index ac88219ba8d6..648bb31c8682 100644
--- a/drivers/infiniband/hw/mana/device.c
+++ b/drivers/infiniband/hw/mana/device.c
@@ -51,7 +51,7 @@ static int mana_ib_probe(struct auxiliary_device *adev,
 {
 	struct mana_adev *madev = container_of(adev, struct mana_adev, adev);
 	struct gdma_dev *mdev = madev->mdev;
-	struct net_device *upper_ndev;
+	struct net_device *ndev;
 	struct mana_context *mc;
 	struct mana_ib_dev *dev;
 	int ret;
@@ -78,15 +78,15 @@ static int mana_ib_probe(struct auxiliary_device *adev,
 	dev->ib_dev.num_comp_vectors = 1;
 	dev->ib_dev.dev.parent = mdev->gdma_context->dev;
 
-	rcu_read_lock(); /* required to get upper dev */
-	upper_ndev = netdev_master_upper_dev_get_rcu(mc->ports[0]);
-	if (!upper_ndev) {
+	rcu_read_lock(); /* required to get primary netdev */
+	ndev = mana_get_primary_netdev_rcu(mc, 0);
+	if (!ndev) {
 		rcu_read_unlock();
 		ret = -ENODEV;
-		ibdev_err(&dev->ib_dev, "Failed to get master netdev");
+		ibdev_err(&dev->ib_dev, "Failed to get netdev for IB port 1");
 		goto free_ib_device;
 	}
-	ret = ib_device_set_netdev(&dev->ib_dev, upper_ndev, 1);
+	ret = ib_device_set_netdev(&dev->ib_dev, ndev, 1);
 	rcu_read_unlock();
 	if (ret) {
 		ibdev_err(&dev->ib_dev, "Failed to set ib netdev, ret %d", ret);
diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
index 4934449f90f5..89ef53b4d2d1 100644
--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
+++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
@@ -3184,3 +3184,22 @@ void mana_remove(struct gdma_dev *gd, bool suspending)
 	kfree(ac);
 	dev_dbg(dev, "%s succeeded\n", __func__);
 }
+
+struct net_device *mana_get_primary_netdev_rcu(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;
+
+	/* 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_primary_netdev_rcu, NET_MANA);
diff --git a/include/net/mana/mana.h b/include/net/mana/mana.h
index 9d387a9c3047..23edf649e65a 100644
--- a/include/net/mana/mana.h
+++ b/include/net/mana/mana.h
@@ -827,4 +827,6 @@ 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_primary_netdev_rcu(struct mana_context *ac, u32 port_index);
 #endif /* _MANA_H */
-- 
2.43.0