[PATCH for-next v6 02/12] RDMA/core: Allow calling query_port when netdev isn't attached in iWarp

[Cheng Xu <chengyou@linux.alibaba.com>]

This change lets the iWarp device drivers decide the return value of
iw_query_port when attached netdev is NULL. This allows ib_register_device
calling when netdev is NULL.

background info:
https://lore.kernel.org/all/20220118141324.GF8034@ziepe.ca/

Signed-off-by: Cheng Xu <chengyou@linux.alibaba.com>
---
 drivers/infiniband/core/device.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/infiniband/core/device.c b/drivers/infiniband/core/device.c
index a311df07b1bd..1638b1188dc8 100644
--- a/drivers/infiniband/core/device.c
+++ b/drivers/infiniband/core/device.c
@@ -2019,8 +2019,12 @@ static int iw_query_port(struct ib_device *device,
 	memset(port_attr, 0, sizeof(*port_attr));
 
 	netdev = ib_device_get_netdev(device, port_num);
+	/* Some iwarp device may be not binded to a netdev temporarily when
+	 * ib_register_device called. To adapt this scenario, allowing iWarp
+	 * device drivers decide the return value.
+	 */
 	if (!netdev)
-		return -ENODEV;
+		goto query_port;
 
 	port_attr->max_mtu = IB_MTU_4096;
 	port_attr->active_mtu = ib_mtu_int_to_enum(netdev->mtu);
@@ -2045,6 +2049,7 @@ static int iw_query_port(struct ib_device *device,
 	}
 
 	dev_put(netdev);
+query_port:
 	return device->ops.query_port(device, port_num, port_attr);
 }
 
-- 
2.27.0