RDMA/restrack: Add support to get resource tracking for SRQ

In order to track SRQ resources, a new restrack object is initialized and
added to the resource tracking database.

Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Neta Ostrovsky <[e-mail]>
Reviewed-by: Mark Zhang <[e-mail]>
Signed-off-by: Leon Romanovsky <[e-mail]>
Signed-off-by: Jason Gunthorpe <[e-mail]>

drivers/infiniband/core/restrack.c

···
 		[RDMA_RESTRACK_MR] = "MR",
 		[RDMA_RESTRACK_CTX] = "CTX",
 		[RDMA_RESTRACK_COUNTER] = "COUNTER",
+		[RDMA_RESTRACK_SRQ] = "SRQ",
 	};
 
 	return names[type];
···
 		return container_of(res, struct ib_ucontext, res)->device;
 	case RDMA_RESTRACK_COUNTER:
 		return container_of(res, struct rdma_counter, res)->device;
+	case RDMA_RESTRACK_SRQ:
+		return container_of(res, struct ib_srq, res)->device;
 	default:
 		WARN_ONCE(true, "Wrong resource tracking type %u\n", res->type);
 		return NULL;

drivers/infiniband/core/verbs.c

···
 	}
 	atomic_inc(&pd->usecnt);
 
+	rdma_restrack_new(&srq->res, RDMA_RESTRACK_SRQ);
+	rdma_restrack_parent_name(&srq->res, &pd->res);
+
 	ret = pd->device->ops.create_srq(srq, srq_init_attr, udata);
 	if (ret) {
+		rdma_restrack_put(&srq->res);
 		atomic_dec(&srq->pd->usecnt);
 		if (srq->srq_type == IB_SRQT_XRC)
 			atomic_dec(&srq->ext.xrc.xrcd->usecnt);
···
 		kfree(srq);
 		return ERR_PTR(ret);
 	}
+
+	rdma_restrack_add(&srq->res);
 
 	return srq;
 }
···
 		atomic_dec(&srq->ext.xrc.xrcd->usecnt);
 	if (ib_srq_has_cq(srq->srq_type))
 		atomic_dec(&srq->ext.cq->usecnt);
+	rdma_restrack_del(&srq->res);
 	kfree(srq);
 
 	return ret;

include/rdma/ib_verbs.h

···
 			} xrc;
 		};
 	} ext;
+
+	/*
+	 * Implementation details of the RDMA core, don't use in drivers:
+	 */
+	struct rdma_restrack_entry res;
 };
 
 enum ib_raw_packet_caps {

include/rdma/restrack.h

···
 	 */
 	RDMA_RESTRACK_COUNTER,
 	/**
+	 * @RDMA_RESTRACK_SRQ: Shared receive queue (SRQ)
+	 */
+	RDMA_RESTRACK_SRQ,
+	/**
 	 * @RDMA_RESTRACK_MAX: Last entry, used for array dclarations
 	 */
 	RDMA_RESTRACK_MAX