IB/core: Add per port immutable struct to ib_device

As of commit 5eb620c81ce3 "IB/core: Add helpers for uncached GID and P_Key
searches"; pkey_tbl_len and gid_tbl_len are immutable data which are stored in
the ib_device.

The per port core capability flags to be added later are also immutable data to
be stored in the ib_device object.

In preparation for this create a structure for per port immutable data and
place the pkey and gid table lengths within this structure.

"get_port_immutable" is added as a mandatory device function to allow the
drivers to fill in this data.

Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index 64f5914..f46b1be 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -2123,6 +2123,22 @@
 	kfree(ibdev->eq_table);
 }
 
+static int mlx4_port_immutable(struct ib_device *ibdev, u8 port_num,
+			       struct ib_port_immutable *immutable)
+{
+	struct ib_port_attr attr;
+	int err;
+
+	err = mlx4_ib_query_port(ibdev, port_num, &attr);
+	if (err)
+		return err;
+
+	immutable->pkey_tbl_len = attr.pkey_tbl_len;
+	immutable->gid_tbl_len = attr.gid_tbl_len;
+
+	return 0;
+}
+
 static void *mlx4_ib_add(struct mlx4_dev *dev)
 {
 	struct mlx4_ib_dev *ibdev;
@@ -2251,6 +2267,7 @@
 	ibdev->ib_dev.attach_mcast	= mlx4_ib_mcg_attach;
 	ibdev->ib_dev.detach_mcast	= mlx4_ib_mcg_detach;
 	ibdev->ib_dev.process_mad	= mlx4_ib_process_mad;
+	ibdev->ib_dev.get_port_immutable = mlx4_port_immutable;
 
 	if (!mlx4_is_slave(ibdev->dev)) {
 		ibdev->ib_dev.alloc_fmr		= mlx4_ib_fmr_alloc;