sunrpc: add add sysfs directory per xprt under each xprt_switch

Add individual transport directories under each transport switch
group. For instance, for each nconnect=X connections there will be
a transport directory. Naming conventions also identifies transport
type -- xprt-<id>-<type> where type is udp, tcp, rdma, local, bc.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
diff --git a/net/sunrpc/sysfs.c b/net/sunrpc/sysfs.c
index 0aa6374..20f7570 100644
--- a/net/sunrpc/sysfs.c
+++ b/net/sunrpc/sysfs.c
@@ -82,6 +82,14 @@ static void rpc_sysfs_xprt_switch_release(struct kobject *kobj)
 	kfree(xprt_switch);
 }
 
+static void rpc_sysfs_xprt_release(struct kobject *kobj)
+{
+	struct rpc_sysfs_xprt *xprt;
+
+	xprt = container_of(kobj, struct rpc_sysfs_xprt, kobject);
+	kfree(xprt);
+}
+
 static const void *rpc_sysfs_client_namespace(struct kobject *kobj)
 {
 	return container_of(kobj, struct rpc_sysfs_client, kobject)->net;
@@ -92,6 +100,12 @@ static const void *rpc_sysfs_xprt_switch_namespace(struct kobject *kobj)
 	return container_of(kobj, struct rpc_sysfs_xprt_switch, kobject)->net;
 }
 
+static const void *rpc_sysfs_xprt_namespace(struct kobject *kobj)
+{
+	return container_of(kobj, struct rpc_sysfs_xprt,
+			    kobject)->xprt->xprt_net;
+}
+
 static struct kobj_type rpc_sysfs_client_type = {
 	.release = rpc_sysfs_client_release,
 	.sysfs_ops = &kobj_sysfs_ops,
@@ -104,6 +118,12 @@ static struct kobj_type rpc_sysfs_xprt_switch_type = {
 	.namespace = rpc_sysfs_xprt_switch_namespace,
 };
 
+static struct kobj_type rpc_sysfs_xprt_type = {
+	.release = rpc_sysfs_xprt_release,
+	.sysfs_ops = &kobj_sysfs_ops,
+	.namespace = rpc_sysfs_xprt_namespace,
+};
+
 void rpc_sysfs_exit(void)
 {
 	kobject_put(rpc_sunrpc_client_kobj);
@@ -151,6 +171,25 @@ rpc_sysfs_xprt_switch_alloc(struct kobject *parent,
 	return NULL;
 }
 
+static struct rpc_sysfs_xprt *rpc_sysfs_xprt_alloc(struct kobject *parent,
+						   struct rpc_xprt *xprt,
+						   gfp_t gfp_flags)
+{
+	struct rpc_sysfs_xprt *p;
+
+	p = kzalloc(sizeof(*p), gfp_flags);
+	if (!p)
+		goto out;
+	p->kobject.kset = rpc_sunrpc_kset;
+	if (kobject_init_and_add(&p->kobject, &rpc_sysfs_xprt_type,
+				 parent, "xprt-%d-%s", xprt->id,
+				 xprt->address_strings[RPC_DISPLAY_PROTO]) == 0)
+		return p;
+	kobject_put(&p->kobject);
+out:
+	return NULL;
+}
+
 void rpc_sysfs_client_setup(struct rpc_clnt *clnt,
 			    struct rpc_xprt_switch *xprt_switch,
 			    struct net *net)
@@ -199,6 +238,22 @@ void rpc_sysfs_xprt_switch_setup(struct rpc_xprt_switch *xprt_switch,
 	}
 }
 
+void rpc_sysfs_xprt_setup(struct rpc_xprt_switch *xprt_switch,
+			  struct rpc_xprt *xprt,
+			  gfp_t gfp_flags)
+{
+	struct rpc_sysfs_xprt *rpc_xprt;
+	struct rpc_sysfs_xprt_switch *switch_obj =
+		(struct rpc_sysfs_xprt_switch *)xprt_switch->xps_sysfs;
+
+	rpc_xprt = rpc_sysfs_xprt_alloc(&switch_obj->kobject, xprt, gfp_flags);
+	if (rpc_xprt) {
+		xprt->xprt_sysfs = rpc_xprt;
+		rpc_xprt->xprt = xprt;
+		kobject_uevent(&rpc_xprt->kobject, KOBJ_ADD);
+	}
+}
+
 void rpc_sysfs_client_destroy(struct rpc_clnt *clnt)
 {
 	struct rpc_sysfs_client *rpc_client = clnt->cl_sysfs;
@@ -225,3 +280,15 @@ void rpc_sysfs_xprt_switch_destroy(struct rpc_xprt_switch *xprt_switch)
 		xprt_switch->xps_sysfs = NULL;
 	}
 }
+
+void rpc_sysfs_xprt_destroy(struct rpc_xprt *xprt)
+{
+	struct rpc_sysfs_xprt *rpc_xprt = xprt->xprt_sysfs;
+
+	if (rpc_xprt) {
+		kobject_uevent(&rpc_xprt->kobject, KOBJ_REMOVE);
+		kobject_del(&rpc_xprt->kobject);
+		kobject_put(&rpc_xprt->kobject);
+		xprt->xprt_sysfs = NULL;
+	}
+}