On Wed, Jul 21, 2021 at 07:48:48AM +0100, Christoph Hellwig wrote:

quoted

+struct ib_qp *ib_create_qp_user(struct ib_device *dev, struct ib_pd *pd,
+				struct ib_qp_init_attr *attr,
+				struct ib_udata *udata,
+				struct ib_uqp_object *uobj, const char *caller);
+static inline struct ib_qp *ib_create_qp_uverbs(struct ib_device *dev,
+						struct ib_pd *pd,
+						struct ib_qp_init_attr *attr,
+						struct ib_udata *udata,
+						struct ib_uqp_object *uobj)
+{
+	if (attr->qp_type == IB_QPT_XRC_TGT)
+		return ib_create_qp_user(dev, pd, attr, NULL, uobj,
+					 KBUILD_MODNAME);
+
+	return ib_create_qp_user(dev, pd, attr, udata, uobj, NULL);

Why not always pass along the udata and caller and just not use them
in the low-level code?

You will need to add some sort of "if qp tpye" for ib_create_qp_uverbs() callers,
because they always provide udata != NULL. 

After this series, the callers look like this:

 1438         qp = ib_create_qp_uverbs(device, pd, &attr, &attrs->driver_udata, obj);
                                                          ^^^^^^^^^ not NULL

So instead of bothering callers, I implemented it here with one "if".

Thanks