vfio/mlx5: Check whether VF is migratable

Add a check whether VF is migratable. Only if VF is migratable, mark the
VFIO device as migration capable.
Signed-off-by: Shay Drory <shayd@nvidia.com>
Signed-off-by: Yishai Hadas <yishaih@nvidia.com>
Link: https://lore.kernel.org/r/20230124144955.139901-2-yishaih@nvidia.comSigned-off-by: Alex Williamson <alex.williamson@redhat.com>

drivers/vfio/pci/mlx5/cmd.c

@@ -7,6 +7,29 @@
 
 enum { CQ_OK = 0, CQ_EMPTY = -1, CQ_POLL_ERR = -2 };
 
+static int mlx5vf_is_migratable(struct mlx5_core_dev *mdev, u16 func_id)
+{
+	int query_sz = MLX5_ST_SZ_BYTES(query_hca_cap_out);
+	void *query_cap = NULL, *cap;
+	int ret;
+
+	query_cap = kzalloc(query_sz, GFP_KERNEL);
+	if (!query_cap)
+		return -ENOMEM;
+
+	ret = mlx5_vport_get_other_func_cap(mdev, func_id, query_cap,
+					    MLX5_CAP_GENERAL_2);
+	if (ret)
+		goto out;
+
+	cap = MLX5_ADDR_OF(query_hca_cap_out, query_cap, capability);
+	if (!MLX5_GET(cmd_hca_cap_2, cap, migratable))
+		ret = -EOPNOTSUPP;
+out:
+	kfree(query_cap);
+	return ret;
+}
+
 static int mlx5vf_cmd_get_vhca_id(struct mlx5_core_dev *mdev, u16 function_id,
 				  u16 *vhca_id);
 static void
@@ -195,6 +218,10 @@ void mlx5vf_cmd_set_migratable(struct mlx5vf_pci_core_device *mvdev,
 	if (mvdev->vf_id < 0)
 		goto end;
 
+	ret = mlx5vf_is_migratable(mvdev->mdev, mvdev->vf_id + 1);
+	if (ret)
+		goto end;
+
 	if (mlx5vf_cmd_get_vhca_id(mvdev->mdev, mvdev->vf_id + 1,
 				   &mvdev->vhca_id))
 		goto end;

drivers/vfio/pci/mlx5/cmd.h

@@ -9,6 +9,7 @@
 #include <linux/kernel.h>
 #include <linux/vfio_pci_core.h>
 #include <linux/mlx5/driver.h>
+#include <linux/mlx5/vport.h>
 #include <linux/mlx5/cq.h>
 #include <linux/mlx5/qp.h>