RDMA/restrack: Improve readability in task name management

Use rdma_restrack_set_name() and rdma_restrack_parent_name() instead of
tricky uses of rdma_restrack_attach_task()/rdma_restrack_uadd().

This uniformly makes all restracks add'd using rdma_restrack_add().

Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Leon Romanovsky <[email protected]>
Signed-off-by: Jason Gunthorpe <[email protected]>

Author: Leon Romanovsky

drivers/infiniband/core/cma.c

@@ -453,10 +453,8 @@ static void _cma_attach_to_dev(struct rdma_id_private *id_priv,
 	id_priv->id.route.addr.dev_addr.transport =
 		rdma_node_get_transport(cma_dev->device->node_type);
 	list_add_tail(&id_priv->list, &cma_dev->id_list);
-	if (id_priv->res.kern_name)
-		rdma_restrack_add(&id_priv->res);
-	else
-		rdma_restrack_uadd(&id_priv->res);
+	rdma_restrack_add(&id_priv->res);
+
 	trace_cm_id_attach(id_priv, cma_dev->device);
 }
 
@@ -822,10 +820,10 @@ static void cma_id_put(struct rdma_id_private *id_priv)
 		complete(&id_priv->comp);
 }
 
-struct rdma_cm_id *__rdma_create_id(struct net *net,
-				    rdma_cm_event_handler event_handler,
-				    void *context, enum rdma_ucm_port_space ps,
-				    enum ib_qp_type qp_type, const char *caller)
+static struct rdma_id_private *
+__rdma_create_id(struct net *net, rdma_cm_event_handler event_handler,
+		 void *context, enum rdma_ucm_port_space ps,
+		 enum ib_qp_type qp_type, const struct rdma_id_private *parent)
 {
 	struct rdma_id_private *id_priv;
 
@@ -853,11 +851,44 @@ struct rdma_cm_id *__rdma_create_id(struct net *net,
 	id_priv->seq_num &= 0x00ffffff;
 
 	rdma_restrack_new(&id_priv->res, RDMA_RESTRACK_CM_ID);
-	rdma_restrack_set_task(&id_priv->res, caller);
+	if (parent)
+		rdma_restrack_parent_name(&id_priv->res, &parent->res);
 
-	return &id_priv->id;
+	return id_priv;
+}
+
+struct rdma_cm_id *
+__rdma_create_kernel_id(struct net *net, rdma_cm_event_handler event_handler,
+			void *context, enum rdma_ucm_port_space ps,
+			enum ib_qp_type qp_type, const char *caller)
+{
+	struct rdma_id_private *ret;
+
+	ret = __rdma_create_id(net, event_handler, context, ps, qp_type, NULL);
+	if (IS_ERR(ret))
+		return ERR_CAST(ret);
+
+	rdma_restrack_set_name(&ret->res, caller);
+	return &ret->id;
+}
+EXPORT_SYMBOL(__rdma_create_kernel_id);
+
+struct rdma_cm_id *rdma_create_user_id(rdma_cm_event_handler event_handler,
+				       void *context,
+				       enum rdma_ucm_port_space ps,
+				       enum ib_qp_type qp_type)
+{
+	struct rdma_id_private *ret;
+
+	ret = __rdma_create_id(current->nsproxy->net_ns, event_handler, context,
+			       ps, qp_type, NULL);
+	if (IS_ERR(ret))
+		return ERR_CAST(ret);
+
+	rdma_restrack_set_name(&ret->res, NULL);
+	return &ret->id;
 }
-EXPORT_SYMBOL(__rdma_create_id);
+EXPORT_SYMBOL(rdma_create_user_id);
 
 static int cma_init_ud_qp(struct rdma_id_private *id_priv, struct ib_qp *qp)
 {
@@ -2029,14 +2060,15 @@ cma_ib_new_conn_id(const struct rdma_cm_id *listen_id,
 	int ret;
 
 	listen_id_priv = container_of(listen_id, struct rdma_id_private, id);
-	id = __rdma_create_id(listen_id->route.addr.dev_addr.net,
-			    listen_id->event_handler, listen_id->context,
-			    listen_id->ps, ib_event->param.req_rcvd.qp_type,
-			    listen_id_priv->res.kern_name);
-	if (IS_ERR(id))
+	id_priv = __rdma_create_id(listen_id->route.addr.dev_addr.net,
+				   listen_id->event_handler, listen_id->context,
+				   listen_id->ps,
+				   ib_event->param.req_rcvd.qp_type,
+				   listen_id_priv);
+	if (IS_ERR(id_priv))
 		return NULL;
 
-	id_priv = container_of(id, struct rdma_id_private, id);
+	id = &id_priv->id;
 	if (cma_save_net_info((struct sockaddr *)&id->route.addr.src_addr,
 			      (struct sockaddr *)&id->route.addr.dst_addr,
 			      listen_id, ib_event, ss_family, service_id))
@@ -2090,13 +2122,13 @@ cma_ib_new_udp_id(const struct rdma_cm_id *listen_id,
 	int ret;
 
 	listen_id_priv = container_of(listen_id, struct rdma_id_private, id);
-	id = __rdma_create_id(net, listen_id->event_handler, listen_id->context,
-			      listen_id->ps, IB_QPT_UD,
-			      listen_id_priv->res.kern_name);
-	if (IS_ERR(id))
+	id_priv = __rdma_create_id(net, listen_id->event_handler,
+				   listen_id->context, listen_id->ps, IB_QPT_UD,
+				   listen_id_priv);
+	if (IS_ERR(id_priv))
 		return NULL;
 
-	id_priv = container_of(id, struct rdma_id_private, id);
+	id = &id_priv->id;
 	if (cma_save_net_info((struct sockaddr *)&id->route.addr.src_addr,
 			      (struct sockaddr *)&id->route.addr.dst_addr,
 			      listen_id, ib_event, ss_family,
@@ -2332,7 +2364,6 @@ static int cma_iw_handler(struct iw_cm_id *iw_id, struct iw_cm_event *iw_event)
 static int iw_conn_req_handler(struct iw_cm_id *cm_id,
 			       struct iw_cm_event *iw_event)
 {
-	struct rdma_cm_id *new_cm_id;
 	struct rdma_id_private *listen_id, *conn_id;
 	struct rdma_cm_event event = {};
 	int ret = -ECONNABORTED;
@@ -2352,16 +2383,14 @@ static int iw_conn_req_handler(struct iw_cm_id *cm_id,
 		goto out;
 
 	/* Create a new RDMA id for the new IW CM ID */
-	new_cm_id = __rdma_create_id(listen_id->id.route.addr.dev_addr.net,
-				     listen_id->id.event_handler,
-				     listen_id->id.context,
-				     RDMA_PS_TCP, IB_QPT_RC,
-				     listen_id->res.kern_name);
-	if (IS_ERR(new_cm_id)) {
+	conn_id = __rdma_create_id(listen_id->id.route.addr.dev_addr.net,
+				   listen_id->id.event_handler,
+				   listen_id->id.context, RDMA_PS_TCP,
+				   IB_QPT_RC, listen_id);
+	if (IS_ERR(conn_id)) {
 		ret = -ENOMEM;
 		goto out;
 	}
-	conn_id = container_of(new_cm_id, struct rdma_id_private, id);
 	mutex_lock_nested(&conn_id->handler_mutex, SINGLE_DEPTH_NESTING);
 	conn_id->state = RDMA_CM_CONNECT;
 
@@ -2466,7 +2495,6 @@ static void cma_listen_on_dev(struct rdma_id_private *id_priv,
 			      struct cma_device *cma_dev)
 {
 	struct rdma_id_private *dev_id_priv;
-	struct rdma_cm_id *id;
 	struct net *net = id_priv->id.route.addr.dev_addr.net;
 	int ret;
 
@@ -2475,13 +2503,12 @@ static void cma_listen_on_dev(struct rdma_id_private *id_priv,
 	if (cma_family(id_priv) == AF_IB && !rdma_cap_ib_cm(cma_dev->device, 1))
 		return;
 
-	id = __rdma_create_id(net, cma_listen_handler, id_priv, id_priv->id.ps,
-			      id_priv->id.qp_type, id_priv->res.kern_name);
-	if (IS_ERR(id))
+	dev_id_priv =
+		__rdma_create_id(net, cma_listen_handler, id_priv,
+				 id_priv->id.ps, id_priv->id.qp_type, id_priv);
+	if (IS_ERR(dev_id_priv))
 		return;
 
-	dev_id_priv = container_of(id, struct rdma_id_private, id);
-
 	dev_id_priv->state = RDMA_CM_ADDR_BOUND;
 	memcpy(cma_src_addr(dev_id_priv), cma_src_addr(id_priv),
 	       rdma_addr_size(cma_src_addr(id_priv)));
@@ -2494,7 +2521,7 @@ static void cma_listen_on_dev(struct rdma_id_private *id_priv,
 	dev_id_priv->tos_set = id_priv->tos_set;
 	dev_id_priv->tos = id_priv->tos;
 
-	ret = rdma_listen(id, id_priv->backlog);
+	ret = rdma_listen(&dev_id_priv->id, id_priv->backlog);
 	if (ret)
 		dev_warn(&cma_dev->device->dev,
 			 "RDMA CMA: cma_listen_on_dev, error %d\n", ret);
@@ -4149,17 +4176,32 @@ static int cma_send_sidr_rep(struct rdma_id_private *id_priv,
 	return ib_send_cm_sidr_rep(id_priv->cm_id.ib, &rep);
 }
 
-int __rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param,
-		  const char *caller)
+/**
+ * rdma_accept - Called to accept a connection request or response.
+ * @id: Connection identifier associated with the request.
+ * @conn_param: Information needed to establish the connection.  This must be
+ *   provided if accepting a connection request.  If accepting a connection
+ *   response, this parameter must be NULL.
+ *
+ * Typically, this routine is only called by the listener to accept a connection
+ * request.  It must also be called on the active side of a connection if the
+ * user is performing their own QP transitions.
+ *
+ * In the case of error, a reject message is sent to the remote side and the
+ * state of the qp associated with the id is modified to error, such that any
+ * previously posted receive buffers would be flushed.
+ *
+ * This function is for use by kernel ULPs and must be called from under the
+ * handler callback.
+ */
+int rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param)
 {
 	struct rdma_id_private *id_priv =
 		container_of(id, struct rdma_id_private, id);
 	int ret;
 
 	lockdep_assert_held(&id_priv->handler_mutex);
 
-	rdma_restrack_set_task(&id_priv->res, caller);
-
 	if (READ_ONCE(id_priv->state) != RDMA_CM_CONNECT)
 		return -EINVAL;
 
@@ -4198,20 +4240,20 @@ int __rdma_accept(struct rdma_cm_id *id, struct rdma_conn_param *conn_param,
 	rdma_reject(id, NULL, 0, IB_CM_REJ_CONSUMER_DEFINED);
 	return ret;
 }
-EXPORT_SYMBOL(__rdma_accept);
+EXPORT_SYMBOL(rdma_accept);
 
-int __rdma_accept_ece(struct rdma_cm_id *id, struct rdma_conn_param *conn_param,
-		      const char *caller, struct rdma_ucm_ece *ece)
+int rdma_accept_ece(struct rdma_cm_id *id, struct rdma_conn_param *conn_param,
+		    struct rdma_ucm_ece *ece)
 {
 	struct rdma_id_private *id_priv =
 		container_of(id, struct rdma_id_private, id);
 
 	id_priv->ece.vendor_id = ece->vendor_id;
 	id_priv->ece.attr_mod = ece->attr_mod;
 
-	return __rdma_accept(id, conn_param, caller);
+	return rdma_accept(id, conn_param);
 }
-EXPORT_SYMBOL(__rdma_accept_ece);
+EXPORT_SYMBOL(rdma_accept_ece);
 
 void rdma_lock_handler(struct rdma_cm_id *id)
 {

drivers/infiniband/core/core_priv.h

@@ -361,15 +361,9 @@ static inline struct ib_qp *_ib_create_qp(struct ib_device *dev,
 	 */
 	is_xrc = qp_type == IB_QPT_XRC_INI || qp_type == IB_QPT_XRC_TGT;
 	if ((qp_type < IB_QPT_MAX && !is_xrc) || qp_type == IB_QPT_DRIVER) {
-		if (uobj)
-			rdma_restrack_uadd(&qp->res);
-		else {
-			rdma_restrack_set_task(&qp->res, pd->res.kern_name);
-			rdma_restrack_add(&qp->res);
-		}
-	} else
-		qp->res.valid = false;
-
+		rdma_restrack_parent_name(&qp->res, &pd->res);
+		rdma_restrack_add(&qp->res);
+	}
 	return qp;
 }
 

drivers/infiniband/core/counters.c

@@ -250,13 +250,8 @@ static struct rdma_counter *rdma_get_counter_auto_mode(struct ib_qp *qp,
 static void rdma_counter_res_add(struct rdma_counter *counter,
 				 struct ib_qp *qp)
 {
-	if (rdma_is_kernel_res(&qp->res)) {
-		rdma_restrack_set_task(&counter->res, qp->res.kern_name);
-		rdma_restrack_add(&counter->res);
-	} else {
-		rdma_restrack_attach_task(&counter->res, qp->res.task);
-		rdma_restrack_uadd(&counter->res);
-	}
+	rdma_restrack_parent_name(&counter->res, &qp->res);
+	rdma_restrack_add(&counter->res);
 }
 
 static void counter_release(struct kref *kref)

drivers/infiniband/core/cq.c

@@ -236,7 +236,7 @@ struct ib_cq *__ib_alloc_cq(struct ib_device *dev, void *private, int nr_cqe,
 		goto out_free_cq;
 
 	rdma_restrack_new(&cq->res, RDMA_RESTRACK_CQ);
-	rdma_restrack_set_task(&cq->res, caller);
+	rdma_restrack_set_name(&cq->res, caller);
 
 	ret = dev->ops.create_cq(cq, &cq_attr, NULL);
 	if (ret)

drivers/infiniband/core/restrack.c

@@ -147,34 +147,56 @@ static struct ib_device *res_to_dev(struct rdma_restrack_entry *res)
 	}
 }
 
-void rdma_restrack_set_task(struct rdma_restrack_entry *res,
-			    const char *caller)
+/**
+ * rdma_restrack_attach_task() - attach the task onto this resource,
+ * valid for user space restrack entries.
+ * @res:  resource entry
+ * @task: the task to attach
+ */
+static void rdma_restrack_attach_task(struct rdma_restrack_entry *res,
+				      struct task_struct *task)
 {
-	if (caller) {
-		res->kern_name = caller;
+	if (WARN_ON_ONCE(!task))
 		return;
-	}
 
 	if (res->task)
 		put_task_struct(res->task);
-	get_task_struct(current);
-	res->task = current;
+	get_task_struct(task);
+	res->task = task;
+	res->user = true;
 }
-EXPORT_SYMBOL(rdma_restrack_set_task);
 
 /**
- * rdma_restrack_attach_task() - attach the task onto this resource
+ * rdma_restrack_set_name() - set the task for this resource
  * @res:  resource entry
- * @task: the task to attach, the current task will be used if it is NULL.
+ * @caller: kernel name, the current task will be used if the caller is NULL.
  */
-void rdma_restrack_attach_task(struct rdma_restrack_entry *res,
-			       struct task_struct *task)
+void rdma_restrack_set_name(struct rdma_restrack_entry *res, const char *caller)
 {
-	if (res->task)
-		put_task_struct(res->task);
-	get_task_struct(task);
-	res->task = task;
+	if (caller) {
+		res->kern_name = caller;
+		return;
+	}
+
+	rdma_restrack_attach_task(res, current);
+}
+EXPORT_SYMBOL(rdma_restrack_set_name);
+
+/**
+ * rdma_restrack_parent_name() - set the restrack name properties based
+ * on parent restrack
+ * @dst: destination resource entry
+ * @parent: parent resource entry
+ */
+void rdma_restrack_parent_name(struct rdma_restrack_entry *dst,
+			       const struct rdma_restrack_entry *parent)
+{
+	if (rdma_is_kernel_res(parent))
+		dst->kern_name = parent->kern_name;
+	else
+		rdma_restrack_attach_task(dst, parent->task);
 }
+EXPORT_SYMBOL(rdma_restrack_parent_name);
 
 /**
  * rdma_restrack_new() - Initializes new restrack entry to allow _put() interface
@@ -229,25 +251,6 @@ void rdma_restrack_add(struct rdma_restrack_entry *res)
 }
 EXPORT_SYMBOL(rdma_restrack_add);
 
-/**
- * rdma_restrack_uadd() - add user object to the reource tracking database
- * @res:  resource entry
- */
-void rdma_restrack_uadd(struct rdma_restrack_entry *res)
-{
-	if ((res->type != RDMA_RESTRACK_CM_ID) &&
-	    (res->type != RDMA_RESTRACK_COUNTER))
-		res->task = NULL;
-
-	if (!res->task)
-		rdma_restrack_set_task(res, NULL);
-	res->kern_name = NULL;
-
-	res->user = true;
-	rdma_restrack_add(res);
-}
-EXPORT_SYMBOL(rdma_restrack_uadd);
-
 int __must_check rdma_restrack_get(struct rdma_restrack_entry *res)
 {
 	return kref_get_unless_zero(&res->kref);

drivers/infiniband/core/restrack.h

@@ -29,6 +29,8 @@ void rdma_restrack_add(struct rdma_restrack_entry *res);
 void rdma_restrack_del(struct rdma_restrack_entry *res);
 void rdma_restrack_new(struct rdma_restrack_entry *res,
 		       enum rdma_restrack_type type);
-void rdma_restrack_attach_task(struct rdma_restrack_entry *res,
-			       struct task_struct *task);
+void rdma_restrack_set_name(struct rdma_restrack_entry *res,
+			    const char *caller);
+void rdma_restrack_parent_name(struct rdma_restrack_entry *dst,
+			       const struct rdma_restrack_entry *parent);
 #endif /* _RDMA_CORE_RESTRACK_H_ */