netdevsim: change debugfs tree topology

With the model where dev is represented by devlink and ports are
represented by devlink ports, make debugfs file names independent
on netdev names. Change the topology to the one illustrated
by the following example:

$ ls /sys/kernel/debug/netdevsim/
netdevsim1
$ ls /sys/kernel/debug/netdevsim/netdevsim1/
bpf_bind_accept  bpf_bind_verifier_delay  bpf_bound_progs  ports
$ ls /sys/kernel/debug/netdevsim/netdevsim1/ports/
0  1
$ ls /sys/kernel/debug/netdevsim/netdevsim1/ports/0/
bpf_map_accept  bpf_offloaded_id  bpf_tc_accept  bpf_tc_non_bound_accept  bpf_xdpdrv_accept  bpf_xdpoffload_accept  dev  ipsec
$ ls /sys/kernel/debug/netdevsim/netdevsim1/ports/0/dev -l
lrwxrwxrwx 1 root root 0 Apr 13 15:58 /sys/kernel/debug/netdevsim/netdevsim1/ports/0/dev -> ../../../netdevsim1

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 11 insertions, 15 deletions

diff --git a/drivers/net/netdevsim/dev.c b/drivers/net/netdevsim/dev.c
index 98a56d8bdcec..14946d162e53 100644
--- a/drivers/net/netdevsim/dev.c
+++ b/drivers/net/netdevsim/dev.c
@@ -27,17 +27,21 @@ static struct dentry *nsim_dev_ddir;
 
 static int nsim_dev_debugfs_init(struct nsim_dev *nsim_dev)
 {
-	char dev_ddir_name[10];
+	char dev_ddir_name[16];
 
-	sprintf(dev_ddir_name, "%u", nsim_dev->nsim_bus_dev->dev.id);
+	sprintf(dev_ddir_name, DRV_NAME "%u", nsim_dev->nsim_bus_dev->dev.id);
 	nsim_dev->ddir = debugfs_create_dir(dev_ddir_name, nsim_dev_ddir);
 	if (IS_ERR_OR_NULL(nsim_dev->ddir))
 		return PTR_ERR_OR_ZERO(nsim_dev->ddir) ?: -EINVAL;
+	nsim_dev->ports_ddir = debugfs_create_dir("ports", nsim_dev->ddir);
+	if (IS_ERR_OR_NULL(nsim_dev->ports_ddir))
+		return PTR_ERR_OR_ZERO(nsim_dev->ports_ddir) ?: -EINVAL;
 	return 0;
 }
 
 static void nsim_dev_debugfs_exit(struct nsim_dev *nsim_dev)
 {
+	debugfs_remove_recursive(nsim_dev->ports_ddir);
 	debugfs_remove_recursive(nsim_dev->ddir);
 }
 
@@ -273,7 +277,7 @@ void nsim_dev_destroy(struct nsim_dev *nsim_dev)
 
 int nsim_dev_init(void)
 {
-	nsim_dev_ddir = debugfs_create_dir(DRV_NAME "_dev", NULL);
+	nsim_dev_ddir = debugfs_create_dir(DRV_NAME, NULL);
 	if (IS_ERR_OR_NULL(nsim_dev_ddir))
 		return -ENOMEM;
 	return 0;
diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c
index 9b4310e20129..eb823bd0dc39 100644
--- a/drivers/net/netdevsim/netdev.c
+++ b/drivers/net/netdevsim/netdev.c
@@ -25,8 +25,6 @@
 
 #include "netdevsim.h"
 
-static struct dentry *nsim_ddir;
-
 static int nsim_get_port_parent_id(struct net_device *dev,
 				   struct netdev_phys_item_id *ppid)
 {
@@ -42,11 +40,11 @@ static int nsim_init(struct net_device *dev)
 	char dev_link_name[32];
 	int err;
 
-	ns->ddir = debugfs_create_dir(netdev_name(dev), nsim_ddir);
+	ns->ddir = debugfs_create_dir("0", ns->nsim_dev->ports_ddir);
 	if (IS_ERR_OR_NULL(ns->ddir))
 		return -ENOMEM;
 
-	sprintf(dev_link_name, "../../" DRV_NAME "_dev/%u",
+	sprintf(dev_link_name, "../../../" DRV_NAME "%u",
 		ns->nsim_dev->nsim_bus_dev->dev.id);
 	debugfs_create_symlink("dev", ns->ddir, dev_link_name);
 
@@ -403,13 +401,9 @@ static int __init nsim_module_init(void)
 {
 	int err;
 
-	nsim_ddir = debugfs_create_dir(DRV_NAME, NULL);
-	if (IS_ERR_OR_NULL(nsim_ddir))
-		return -ENOMEM;
-
 	err = nsim_dev_init();
 	if (err)
-		goto err_debugfs_destroy;
+		return err;
 
 	err = nsim_bus_init();
 	if (err)
@@ -425,8 +419,6 @@ err_bus_exit:
 	nsim_bus_exit();
 err_dev_exit:
 	nsim_dev_exit();
-err_debugfs_destroy:
-	debugfs_remove_recursive(nsim_ddir);
 	return err;
 }
 
@@ -435,7 +427,6 @@ static void __exit nsim_module_exit(void)
 	rtnl_link_unregister(&nsim_link_ops);
 	nsim_bus_exit();
 	nsim_dev_exit();
-	debugfs_remove_recursive(nsim_ddir);
 }
 
 module_init(nsim_module_init);
diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index 17639c7c9032..e951b1ccc3f2 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -134,6 +134,7 @@ struct nsim_dev {
 	struct nsim_bus_dev *nsim_bus_dev;
 	struct nsim_fib_data *fib_data;
 	struct dentry *ddir;
+	struct dentry *ports_ddir;
 	struct bpf_offload_dev *bpf_dev;
 	bool bpf_bind_accept;
 	u32 bpf_bind_verifier_delay;