netdevsim: move shared dev creation and destruction into separate file

To make code easier to read, move shared dev bits into a separate file.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/netdevsim/Makefile

@@ -3,7 +3,7 @@
 obj-$(CONFIG_NETDEVSIM) += netdevsim.o
 
 netdevsim-objs := \
-	netdev.o devlink.o fib.o \
+	netdev.o devlink.o fib.o sdev.o \
 
 ifeq ($(CONFIG_BPF_SYSCALL),y)
 netdevsim-objs += \

drivers/net/netdevsim/netdev.c

@@ -25,6 +25,8 @@
 
 #include "netdevsim.h"
 
+static u32 nsim_dev_id;
+
 struct nsim_vf_config {
 	int link_state;
 	u16 min_tx_rate;
@@ -38,10 +40,7 @@ struct nsim_vf_config {
 	bool rss_query_enabled;
 };
 
-static u32 nsim_dev_id;
-
 static struct dentry *nsim_ddir;
-static struct dentry *nsim_sdev_ddir;
 
 static int nsim_num_vf(struct device *dev)
 {
@@ -158,8 +157,8 @@ static int nsim_get_port_parent_id(struct net_device *dev,
 
 static int nsim_init(struct net_device *dev)
 {
-	char sdev_ddir_name[10], sdev_link_name[32];
 	struct netdevsim *ns = netdev_priv(dev);
+	char sdev_link_name[32];
 	int err;
 
 	ns->netdev = dev;
@@ -167,32 +166,13 @@ static int nsim_init(struct net_device *dev)
 	if (IS_ERR_OR_NULL(ns->ddir))
 		return -ENOMEM;
 
-	if (!ns->sdev) {
-		ns->sdev = kzalloc(sizeof(*ns->sdev), GFP_KERNEL);
-		if (!ns->sdev) {
-			err = -ENOMEM;
-			goto err_debugfs_destroy;
-		}
-		ns->sdev->refcnt = 1;
-		ns->sdev->switch_id = nsim_dev_id;
-		sprintf(sdev_ddir_name, "%u", ns->sdev->switch_id);
-		ns->sdev->ddir = debugfs_create_dir(sdev_ddir_name,
-						    nsim_sdev_ddir);
-		if (IS_ERR_OR_NULL(ns->sdev->ddir)) {
-			err = PTR_ERR_OR_ZERO(ns->sdev->ddir) ?: -EINVAL;
-			goto err_sdev_free;
-		}
-	} else {
-		sprintf(sdev_ddir_name, "%u", ns->sdev->switch_id);
-		ns->sdev->refcnt++;
-	}
-
-	sprintf(sdev_link_name, "../../" DRV_NAME "_sdev/%s", sdev_ddir_name);
+	sprintf(sdev_link_name, "../../" DRV_NAME "_sdev/%u",
+		ns->sdev->switch_id);
 	debugfs_create_symlink("sdev", ns->ddir, sdev_link_name);
 
 	err = nsim_bpf_init(ns);
 	if (err)
-		goto err_sdev_destroy;
+		goto err_debugfs_destroy;
 
 	ns->dev.id = nsim_dev_id++;
 	ns->dev.bus = &nsim_bus;
@@ -215,12 +195,6 @@ static int nsim_init(struct net_device *dev)
 	device_unregister(&ns->dev);
 err_bpf_uninit:
 	nsim_bpf_uninit(ns);
-err_sdev_destroy:
-	if (!--ns->sdev->refcnt) {
-		debugfs_remove_recursive(ns->sdev->ddir);
-err_sdev_free:
-		kfree(ns->sdev);
-	}
 err_debugfs_destroy:
 	debugfs_remove_recursive(ns->ddir);
 	return err;
@@ -234,10 +208,6 @@ static void nsim_uninit(struct net_device *dev)
 	nsim_devlink_teardown(ns);
 	debugfs_remove_recursive(ns->ddir);
 	nsim_bpf_uninit(ns);
-	if (!--ns->sdev->refcnt) {
-		debugfs_remove_recursive(ns->sdev->ddir);
-		kfree(ns->sdev);
-	}
 }
 
 static void nsim_free(struct net_device *dev)
@@ -246,6 +216,7 @@ static void nsim_free(struct net_device *dev)
 
 	device_unregister(&ns->dev);
 	/* netdev and vf state will be freed out of device_release() */
+	nsim_sdev_put(ns->sdev);
 }
 
 static netdev_tx_t nsim_start_xmit(struct sk_buff *skb, struct net_device *dev)
@@ -523,10 +494,11 @@ static int nsim_newlink(struct net *src_net, struct net_device *dev,
 			struct netlink_ext_ack *extack)
 {
 	struct netdevsim *ns = netdev_priv(dev);
+	struct netdevsim *joinns = NULL;
+	int err;
 
 	if (tb[IFLA_LINK]) {
 		struct net_device *joindev;
-		struct netdevsim *joinns;
 
 		joindev = __dev_get_by_index(src_net,
 					     nla_get_u32(tb[IFLA_LINK]));
@@ -536,12 +508,20 @@ static int nsim_newlink(struct net *src_net, struct net_device *dev,
 			return -EINVAL;
 
 		joinns = netdev_priv(joindev);
-		if (!joinns->sdev || !joinns->sdev->refcnt)
-			return -EINVAL;
-		ns->sdev = joinns->sdev;
 	}
 
-	return register_netdevice(dev);
+	ns->sdev = nsim_sdev_get(joinns);
+	if (IS_ERR(ns->sdev))
+		return PTR_ERR(ns->sdev);
+
+	err = register_netdevice(dev);
+	if (err)
+		goto err_sdev_put;
+	return 0;
+
+err_sdev_put:
+	nsim_sdev_put(ns->sdev);
+	return err;
 }
 
 static struct rtnl_link_ops nsim_link_ops __read_mostly = {
@@ -560,15 +540,13 @@ static int __init nsim_module_init(void)
 	if (IS_ERR_OR_NULL(nsim_ddir))
 		return -ENOMEM;
 
-	nsim_sdev_ddir = debugfs_create_dir(DRV_NAME "_sdev", NULL);
-	if (IS_ERR_OR_NULL(nsim_sdev_ddir)) {
-		err = -ENOMEM;
+	err = nsim_sdev_init();
+	if (err)
 		goto err_debugfs_destroy;
-	}
 
 	err = bus_register(&nsim_bus);
 	if (err)
-		goto err_sdir_destroy;
+		goto err_sdev_exit;
 
 	err = nsim_devlink_init();
 	if (err)
@@ -584,8 +562,8 @@ static int __init nsim_module_init(void)
 	nsim_devlink_exit();
 err_unreg_bus:
 	bus_unregister(&nsim_bus);
-err_sdir_destroy:
-	debugfs_remove_recursive(nsim_sdev_ddir);
+err_sdev_exit:
+	nsim_sdev_exit();
 err_debugfs_destroy:
 	debugfs_remove_recursive(nsim_ddir);
 	return err;
@@ -596,7 +574,7 @@ static void __exit nsim_module_exit(void)
 	rtnl_link_unregister(&nsim_link_ops);
 	nsim_devlink_exit();
 	bus_unregister(&nsim_bus);
-	debugfs_remove_recursive(nsim_sdev_ddir);
+	nsim_sdev_exit();
 	debugfs_remove_recursive(nsim_ddir);
 }
 

drivers/net/netdevsim/netdevsim.h

@@ -46,6 +46,13 @@ struct netdevsim_shared_dev {
 	struct list_head bpf_bound_maps;
 };
 
+struct netdevsim;
+
+struct netdevsim_shared_dev *nsim_sdev_get(struct netdevsim *joinns);
+void nsim_sdev_put(struct netdevsim_shared_dev *sdev);
+int nsim_sdev_init(void);
+void nsim_sdev_exit(void);
+
 #define NSIM_IPSEC_MAX_SA_COUNT		33
 #define NSIM_IPSEC_VALID		BIT(31)
 

drivers/net/netdevsim/sdev.c

+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Mellanox Technologies. All rights reserved */
+
+#include <linux/debugfs.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include "netdevsim.h"
+
+static struct dentry *nsim_sdev_ddir;
+
+static u32 nsim_sdev_id;
+
+struct netdevsim_shared_dev *nsim_sdev_get(struct netdevsim *joinns)
+{
+	struct netdevsim_shared_dev *sdev;
+	char sdev_ddir_name[10];
+	int err;
+
+	if (joinns) {
+		if (WARN_ON(!joinns->sdev))
+			return ERR_PTR(-EINVAL);
+		sdev = joinns->sdev;
+		sdev->refcnt++;
+		return sdev;
+	}
+
+	sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
+	if (!sdev)
+		return ERR_PTR(-ENOMEM);
+	sdev->refcnt = 1;
+	sdev->switch_id = nsim_sdev_id++;
+
+	sprintf(sdev_ddir_name, "%u", sdev->switch_id);
+	sdev->ddir = debugfs_create_dir(sdev_ddir_name, nsim_sdev_ddir);
+	if (IS_ERR_OR_NULL(sdev->ddir)) {
+		err = PTR_ERR_OR_ZERO(sdev->ddir) ?: -EINVAL;
+		goto err_sdev_free;
+	}
+
+	return sdev;
+
+err_sdev_free:
+	nsim_sdev_id--;
+	kfree(sdev);
+	return ERR_PTR(err);
+}
+
+void nsim_sdev_put(struct netdevsim_shared_dev *sdev)
+{
+	if (--sdev->refcnt)
+		return;
+	debugfs_remove_recursive(sdev->ddir);
+	kfree(sdev);
+}
+
+int nsim_sdev_init(void)
+{
+	nsim_sdev_ddir = debugfs_create_dir(DRV_NAME "_sdev", NULL);
+	if (IS_ERR_OR_NULL(nsim_sdev_ddir))
+		return -ENOMEM;
+	return 0;
+}
+
+void nsim_sdev_exit(void)
+{
+	debugfs_remove_recursive(nsim_sdev_ddir);
+}