RDMA/nldev: Connect QP number to .doit callback

This patch adds ability to query specific QP based on its LQPN (local
QPN), which is assigned by HW and needs special treatment while inserting
into restrack DB.
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/core/nldev.c

@@ -921,6 +921,7 @@ static const struct nldev_fill_res_entry fill_entries[RDMA_RESTRACK_MAX] = {
 		.nldev_cmd = RDMA_NLDEV_CMD_RES_QP_GET,
 		.nldev_attr = RDMA_NLDEV_ATTR_RES_QP,
 		.entry = RDMA_NLDEV_ATTR_RES_QP_ENTRY,
+		.id = RDMA_NLDEV_ATTR_RES_LQPN,
 	},
 	[RDMA_RESTRACK_CM_ID] = {
 		.fill_res_func = fill_res_cm_id_entry,

drivers/infiniband/core/restrack.c

@@ -225,7 +225,16 @@ static void rdma_restrack_add(struct rdma_restrack_entry *res)
 
 	kref_init(&res->kref);
 	init_completion(&res->comp);
-	ret = rt_xa_alloc_cyclic(&rt->xa, &res->id, res, &rt->next_id);
+	if (res->type != RDMA_RESTRACK_QP)
+		ret = rt_xa_alloc_cyclic(&rt->xa, &res->id, res, &rt->next_id);
+	else {
+		/* Special case to ensure that LQPN points to right QP */
+		struct ib_qp *qp = container_of(res, struct ib_qp, res);
+
+		ret = xa_insert(&rt->xa, qp->qp_num, res, GFP_KERNEL);
+		res->id = ret ? 0 : qp->qp_num;
+	}
+
 	if (!ret)
 		res->valid = true;
 }