Merge branch 'netdevsim-implement-proper-device-model'

Jiri Pirko says:

====================
netdevsim: implement proper device model

Currently the model of netdevsim is a bit odd in multiple ways.
1) devlink instance is not in any way related with actual netdevsim
   netdevices. Instead, it is created per-namespace.
2) multi-port netdevsim device is done using "link" attribute.
3) netdevsim bus is there only to have something to bind the netdev to,
   it really does not act as a bus.
4) netdevsim instances are created by "ip link add" which is great for
   soft devices with no hw backend. The rtnl core allocates netdev and
   calls into driver holding rtnl mutex. For hw-backed devices, this
   flow is wrong as it breaks order in which things are done.

This patchset adjust netdevsim to fix all above.

In order to support proper devlink and devlink port instances and to be
able to emulate real devices, there is need to implement bus probe and
instantiate everything from there. User can specify device id and port
count to be instantianted. For example:

$ echo "10 4" > /sys/bus/netdevsim/new_device

Then devlink shows this:

$ devlink dev
netdevsim/netdevsim10

$ devlink port
netdevsim/netdevsim10/0: type eth netdev eni0np1 flavour physical
netdevsim/netdevsim10/1: type eth netdev eni0np2 flavour physical
netdevsim/netdevsim10/2: type eth netdev eni0np3 flavour physical
netdevsim/netdevsim10/3: type eth netdev eni0np4 flavour physical

There is possible to add and delete ports using their indexes
during netdevsim device lifetime like this:

Then devlink shows this:

$ devlink port
netdevsim/netdevsim10/1: type eth netdev eni10np2 flavour physical
netdevsim/netdevsim10/2: type eth netdev eni10np3 flavour physical
netdevsim/netdevsim10/3: type eth netdev eni10np4 flavour physical
netdevsim/netdevsim10/43: type eth netdev eni10np44 flavour physical

Debugfs topology is also adjusted a bit. The rest stays the same as
before.

Udev bits are merged un systemd upstream git:
https://github.com/systemd/systemd/commit/eaa9d507d85509c8bf727356e3884ec54b0fc646

See individual patches for changelog.
====================
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.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 sdev.o \
+	netdev.o dev.o fib.o bus.o
 
 ifeq ($(CONFIG_BPF_SYSCALL),y)
 netdevsim-objs += \

drivers/net/netdevsim/bpf.c

@@ -27,7 +27,7 @@
 	bpf_verifier_log_write(env, "[netdevsim] " fmt, ##__VA_ARGS__)
 
 struct nsim_bpf_bound_prog {
-	struct netdevsim_shared_dev *sdev;
+	struct nsim_dev *nsim_dev;
 	struct bpf_prog *prog;
 	struct dentry *ddir;
 	const char *state;
@@ -65,8 +65,8 @@ nsim_bpf_verify_insn(struct bpf_verifier_env *env, int insn_idx, int prev_insn)
 	struct nsim_bpf_bound_prog *state;
 
 	state = env->prog->aux->offload->dev_priv;
-	if (state->sdev->bpf_bind_verifier_delay && !insn_idx)
-		msleep(state->sdev->bpf_bind_verifier_delay);
+	if (state->nsim_dev->bpf_bind_verifier_delay && !insn_idx)
+		msleep(state->nsim_dev->bpf_bind_verifier_delay);
 
 	if (insn_idx == env->prog->len - 1)
 		pr_vlog(env, "Hello from netdevsim!\n");
@@ -213,7 +213,7 @@ nsim_xdp_set_prog(struct netdevsim *ns, struct netdev_bpf *bpf,
 	return 0;
 }
 
-static int nsim_bpf_create_prog(struct netdevsim_shared_dev *sdev,
+static int nsim_bpf_create_prog(struct nsim_dev *nsim_dev,
 				struct bpf_prog *prog)
 {
 	struct nsim_bpf_bound_prog *state;
@@ -223,13 +223,13 @@ static int nsim_bpf_create_prog(struct netdevsim_shared_dev *sdev,
 	if (!state)
 		return -ENOMEM;
 
-	state->sdev = sdev;
+	state->nsim_dev = nsim_dev;
 	state->prog = prog;
 	state->state = "verify";
 
 	/* Program id is not populated yet when we create the state. */
-	sprintf(name, "%u", sdev->prog_id_gen++);
-	state->ddir = debugfs_create_dir(name, sdev->ddir_bpf_bound_progs);
+	sprintf(name, "%u", nsim_dev->prog_id_gen++);
+	state->ddir = debugfs_create_dir(name, nsim_dev->ddir_bpf_bound_progs);
 	if (IS_ERR_OR_NULL(state->ddir)) {
 		kfree(state);
 		return -ENOMEM;
@@ -240,7 +240,7 @@ static int nsim_bpf_create_prog(struct netdevsim_shared_dev *sdev,
 			    &state->state, &nsim_bpf_string_fops);
 	debugfs_create_bool("loaded", 0400, state->ddir, &state->is_loaded);
 
-	list_add_tail(&state->l, &sdev->bpf_bound_progs);
+	list_add_tail(&state->l, &nsim_dev->bpf_bound_progs);
 
 	prog->aux->offload->dev_priv = state;
 
@@ -249,13 +249,13 @@ static int nsim_bpf_create_prog(struct netdevsim_shared_dev *sdev,
 
 static int nsim_bpf_verifier_prep(struct bpf_prog *prog)
 {
-	struct netdevsim_shared_dev *sdev =
+	struct nsim_dev *nsim_dev =
 			bpf_offload_dev_priv(prog->aux->offload->offdev);
 
-	if (!sdev->bpf_bind_accept)
+	if (!nsim_dev->bpf_bind_accept)
 		return -EOPNOTSUPP;
 
-	return nsim_bpf_create_prog(sdev, prog);
+	return nsim_bpf_create_prog(nsim_dev, prog);
 }
 
 static int nsim_bpf_translate(struct bpf_prog *prog)
@@ -514,7 +514,7 @@ nsim_bpf_map_alloc(struct netdevsim *ns, struct bpf_offloaded_map *offmap)
 	}
 
 	offmap->dev_ops = &nsim_bpf_map_ops;
-	list_add_tail(&nmap->l, &ns->sdev->bpf_bound_maps);
+	list_add_tail(&nmap->l, &ns->nsim_dev->bpf_bound_maps);
 
 	return 0;
 
@@ -578,77 +578,68 @@ int nsim_bpf(struct net_device *dev, struct netdev_bpf *bpf)
 	}
 }
 
-static int nsim_bpf_sdev_init(struct netdevsim_shared_dev *sdev)
+int nsim_bpf_dev_init(struct nsim_dev *nsim_dev)
 {
 	int err;
 
-	INIT_LIST_HEAD(&sdev->bpf_bound_progs);
-	INIT_LIST_HEAD(&sdev->bpf_bound_maps);
+	INIT_LIST_HEAD(&nsim_dev->bpf_bound_progs);
+	INIT_LIST_HEAD(&nsim_dev->bpf_bound_maps);
 
-	sdev->ddir_bpf_bound_progs =
-		debugfs_create_dir("bpf_bound_progs", sdev->ddir);
-	if (IS_ERR_OR_NULL(sdev->ddir_bpf_bound_progs))
+	nsim_dev->ddir_bpf_bound_progs = debugfs_create_dir("bpf_bound_progs",
+							    nsim_dev->ddir);
+	if (IS_ERR_OR_NULL(nsim_dev->ddir_bpf_bound_progs))
 		return -ENOMEM;
 
-	sdev->bpf_dev = bpf_offload_dev_create(&nsim_bpf_dev_ops, sdev);
-	err = PTR_ERR_OR_ZERO(sdev->bpf_dev);
+	nsim_dev->bpf_dev = bpf_offload_dev_create(&nsim_bpf_dev_ops, nsim_dev);
+	err = PTR_ERR_OR_ZERO(nsim_dev->bpf_dev);
 	if (err)
 		return err;
 
-	sdev->bpf_bind_accept = true;
-	debugfs_create_bool("bpf_bind_accept", 0600, sdev->ddir,
-			    &sdev->bpf_bind_accept);
-	debugfs_create_u32("bpf_bind_verifier_delay", 0600, sdev->ddir,
-			   &sdev->bpf_bind_verifier_delay);
+	nsim_dev->bpf_bind_accept = true;
+	debugfs_create_bool("bpf_bind_accept", 0600, nsim_dev->ddir,
+			    &nsim_dev->bpf_bind_accept);
+	debugfs_create_u32("bpf_bind_verifier_delay", 0600, nsim_dev->ddir,
+			   &nsim_dev->bpf_bind_verifier_delay);
 	return 0;
 }
 
-static void nsim_bpf_sdev_uninit(struct netdevsim_shared_dev *sdev)
+void nsim_bpf_dev_exit(struct nsim_dev *nsim_dev)
 {
-	WARN_ON(!list_empty(&sdev->bpf_bound_progs));
-	WARN_ON(!list_empty(&sdev->bpf_bound_maps));
-	bpf_offload_dev_destroy(sdev->bpf_dev);
+	WARN_ON(!list_empty(&nsim_dev->bpf_bound_progs));
+	WARN_ON(!list_empty(&nsim_dev->bpf_bound_maps));
+	bpf_offload_dev_destroy(nsim_dev->bpf_dev);
 }
 
 int nsim_bpf_init(struct netdevsim *ns)
 {
+	struct dentry *ddir = ns->nsim_dev_port->ddir;
 	int err;
 
-	if (ns->sdev->refcnt == 1) {
-		err = nsim_bpf_sdev_init(ns->sdev);
+	err = bpf_offload_dev_netdev_register(ns->nsim_dev->bpf_dev,
+					      ns->netdev);
 	if (err)
 		return err;
-	}
-
-	err = bpf_offload_dev_netdev_register(ns->sdev->bpf_dev, ns->netdev);
-	if (err)
-		goto err_bpf_sdev_uninit;
 
-	debugfs_create_u32("bpf_offloaded_id", 0400, ns->ddir,
+	debugfs_create_u32("bpf_offloaded_id", 0400, ddir,
 			   &ns->bpf_offloaded_id);
 
 	ns->bpf_tc_accept = true;
-	debugfs_create_bool("bpf_tc_accept", 0600, ns->ddir,
+	debugfs_create_bool("bpf_tc_accept", 0600, ddir,
 			    &ns->bpf_tc_accept);
-	debugfs_create_bool("bpf_tc_non_bound_accept", 0600, ns->ddir,
+	debugfs_create_bool("bpf_tc_non_bound_accept", 0600, ddir,
 			    &ns->bpf_tc_non_bound_accept);
 	ns->bpf_xdpdrv_accept = true;
-	debugfs_create_bool("bpf_xdpdrv_accept", 0600, ns->ddir,
+	debugfs_create_bool("bpf_xdpdrv_accept", 0600, ddir,
 			    &ns->bpf_xdpdrv_accept);
 	ns->bpf_xdpoffload_accept = true;
-	debugfs_create_bool("bpf_xdpoffload_accept", 0600, ns->ddir,
+	debugfs_create_bool("bpf_xdpoffload_accept", 0600, ddir,
 			    &ns->bpf_xdpoffload_accept);
 
 	ns->bpf_map_accept = true;
-	debugfs_create_bool("bpf_map_accept", 0600, ns->ddir,
+	debugfs_create_bool("bpf_map_accept", 0600, ddir,
 			    &ns->bpf_map_accept);
 
 	return 0;
-
-err_bpf_sdev_uninit:
-	if (ns->sdev->refcnt == 1)
-		nsim_bpf_sdev_uninit(ns->sdev);
-	return err;
 }
 
 void nsim_bpf_uninit(struct netdevsim *ns)
@@ -656,8 +647,5 @@ void nsim_bpf_uninit(struct netdevsim *ns)
 	WARN_ON(ns->xdp.prog);
 	WARN_ON(ns->xdp_hw.prog);
 	WARN_ON(ns->bpf_offloaded);
-	bpf_offload_dev_netdev_unregister(ns->sdev->bpf_dev, ns->netdev);
-
-	if (ns->sdev->refcnt == 1)
-		nsim_bpf_sdev_uninit(ns->sdev);
+	bpf_offload_dev_netdev_unregister(ns->nsim_dev->bpf_dev, ns->netdev);
 }

drivers/net/netdevsim/bus.c

+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2017 Netronome Systems, Inc.
+ * Copyright (C) 2019 Mellanox Technologies. All rights reserved
+ */
+
+#include <linux/device.h>
+#include <linux/idr.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/mutex.h>
+#include <linux/rtnetlink.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+
+#include "netdevsim.h"
+
+static DEFINE_IDA(nsim_bus_dev_ids);
+static LIST_HEAD(nsim_bus_dev_list);
+static DEFINE_MUTEX(nsim_bus_dev_list_lock);
+
+static struct nsim_bus_dev *to_nsim_bus_dev(struct device *dev)
+{
+	return container_of(dev, struct nsim_bus_dev, dev);
+}
+
+static int nsim_bus_dev_vfs_enable(struct nsim_bus_dev *nsim_bus_dev,
+				   unsigned int num_vfs)
+{
+	nsim_bus_dev->vfconfigs = kcalloc(num_vfs,
+					  sizeof(struct nsim_vf_config),
+					  GFP_KERNEL);
+	if (!nsim_bus_dev->vfconfigs)
+		return -ENOMEM;
+	nsim_bus_dev->num_vfs = num_vfs;
+
+	return 0;
+}
+
+static void nsim_bus_dev_vfs_disable(struct nsim_bus_dev *nsim_bus_dev)
+{
+	kfree(nsim_bus_dev->vfconfigs);
+	nsim_bus_dev->vfconfigs = NULL;
+	nsim_bus_dev->num_vfs = 0;
+}
+
+static ssize_t
+nsim_bus_dev_numvfs_store(struct device *dev, struct device_attribute *attr,
+			  const char *buf, size_t count)
+{
+	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
+	unsigned int num_vfs;
+	int ret;
+
+	ret = kstrtouint(buf, 0, &num_vfs);
+	if (ret)
+		return ret;
+
+	rtnl_lock();
+	if (nsim_bus_dev->num_vfs == num_vfs)
+		goto exit_good;
+	if (nsim_bus_dev->num_vfs && num_vfs) {
+		ret = -EBUSY;
+		goto exit_unlock;
+	}
+
+	if (num_vfs) {
+		ret = nsim_bus_dev_vfs_enable(nsim_bus_dev, num_vfs);
+		if (ret)
+			goto exit_unlock;
+	} else {
+		nsim_bus_dev_vfs_disable(nsim_bus_dev);
+	}
+exit_good:
+	ret = count;
+exit_unlock:
+	rtnl_unlock();
+
+	return ret;
+}
+
+static ssize_t
+nsim_bus_dev_numvfs_show(struct device *dev,
+			 struct device_attribute *attr, char *buf)
+{
+	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
+
+	return sprintf(buf, "%u\n", nsim_bus_dev->num_vfs);
+}
+
+static struct device_attribute nsim_bus_dev_numvfs_attr =
+	__ATTR(sriov_numvfs, 0664, nsim_bus_dev_numvfs_show,
+	       nsim_bus_dev_numvfs_store);
+
+static ssize_t
+new_port_store(struct device *dev, struct device_attribute *attr,
+	       const char *buf, size_t count)
+{
+	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
+	unsigned int port_index;
+	int ret;
+
+	ret = kstrtouint(buf, 0, &port_index);
+	if (ret)
+		return ret;
+	ret = nsim_dev_port_add(nsim_bus_dev, port_index);
+	return ret ? ret : count;
+}
+
+static struct device_attribute nsim_bus_dev_new_port_attr = __ATTR_WO(new_port);
+
+static ssize_t
+del_port_store(struct device *dev, struct device_attribute *attr,
+	       const char *buf, size_t count)
+{
+	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
+	unsigned int port_index;
+	int ret;
+
+	ret = kstrtouint(buf, 0, &port_index);
+	if (ret)
+		return ret;
+	ret = nsim_dev_port_del(nsim_bus_dev, port_index);
+	return ret ? ret : count;
+}
+
+static struct device_attribute nsim_bus_dev_del_port_attr = __ATTR_WO(del_port);
+
+static struct attribute *nsim_bus_dev_attrs[] = {
+	&nsim_bus_dev_numvfs_attr.attr,
+	&nsim_bus_dev_new_port_attr.attr,
+	&nsim_bus_dev_del_port_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group nsim_bus_dev_attr_group = {
+	.attrs = nsim_bus_dev_attrs,
+};
+
+static const struct attribute_group *nsim_bus_dev_attr_groups[] = {
+	&nsim_bus_dev_attr_group,
+	NULL,
+};
+
+static void nsim_bus_dev_release(struct device *dev)
+{
+	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
+
+	nsim_bus_dev_vfs_disable(nsim_bus_dev);
+}
+
+static struct device_type nsim_bus_dev_type = {
+	.groups = nsim_bus_dev_attr_groups,
+	.release = nsim_bus_dev_release,
+};
+
+static struct nsim_bus_dev *
+nsim_bus_dev_new(unsigned int id, unsigned int port_count);
+
+static ssize_t
+new_device_store(struct bus_type *bus, const char *buf, size_t count)
+{
+	struct nsim_bus_dev *nsim_bus_dev;
+	unsigned int port_count;
+	unsigned int id;
+	int err;
+
+	err = sscanf(buf, "%u %u", &id, &port_count);
+	switch (err) {
+	case 1:
+		port_count = 1;
+		/* pass through */
+	case 2:
+		if (id > INT_MAX) {
+			pr_err("Value of \"id\" is too big.\n");
+			return -EINVAL;
+		}
+		break;
+	default:
+		pr_err("Format for adding new device is \"id port_count\" (uint uint).\n");
+		return -EINVAL;
+	}
+	nsim_bus_dev = nsim_bus_dev_new(id, port_count);
+	if (IS_ERR(nsim_bus_dev))
+		return PTR_ERR(nsim_bus_dev);
+
+	mutex_lock(&nsim_bus_dev_list_lock);
+	list_add_tail(&nsim_bus_dev->list, &nsim_bus_dev_list);
+	mutex_unlock(&nsim_bus_dev_list_lock);
+
+	return count;
+}
+static BUS_ATTR_WO(new_device);
+
+static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev);
+
+static ssize_t
+del_device_store(struct bus_type *bus, const char *buf, size_t count)
+{
+	struct nsim_bus_dev *nsim_bus_dev, *tmp;
+	unsigned int id;
+	int err;
+
+	err = sscanf(buf, "%u", &id);
+	switch (err) {
+	case 1:
+		if (id > INT_MAX) {
+			pr_err("Value of \"id\" is too big.\n");
+			return -EINVAL;
+		}
+		break;
+	default:
+		pr_err("Format for deleting device is \"id\" (uint).\n");
+		return -EINVAL;
+	}
+
+	err = -ENOENT;
+	mutex_lock(&nsim_bus_dev_list_lock);
+	list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) {
+		if (nsim_bus_dev->dev.id != id)
+			continue;
+		list_del(&nsim_bus_dev->list);
+		nsim_bus_dev_del(nsim_bus_dev);
+		err = 0;
+		break;
+	}
+	mutex_unlock(&nsim_bus_dev_list_lock);
+	return !err ? count : err;
+}
+static BUS_ATTR_WO(del_device);
+
+static struct attribute *nsim_bus_attrs[] = {
+	&bus_attr_new_device.attr,
+	&bus_attr_del_device.attr,
+	NULL
+};
+ATTRIBUTE_GROUPS(nsim_bus);
+
+static int nsim_bus_probe(struct device *dev)
+{
+	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
+
+	return nsim_dev_probe(nsim_bus_dev);
+}
+
+static int nsim_bus_remove(struct device *dev)
+{
+	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
+
+	nsim_dev_remove(nsim_bus_dev);
+	return 0;
+}
+
+int nsim_num_vf(struct device *dev)
+{
+	struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
+
+	return nsim_bus_dev->num_vfs;
+}
+
+static struct bus_type nsim_bus = {
+	.name		= DRV_NAME,
+	.dev_name	= DRV_NAME,
+	.bus_groups	= nsim_bus_groups,
+	.probe		= nsim_bus_probe,
+	.remove		= nsim_bus_remove,
+	.num_vf		= nsim_num_vf,
+};
+
+static struct nsim_bus_dev *
+nsim_bus_dev_new(unsigned int id, unsigned int port_count)
+{
+	struct nsim_bus_dev *nsim_bus_dev;
+	int err;
+
+	nsim_bus_dev = kzalloc(sizeof(*nsim_bus_dev), GFP_KERNEL);
+	if (!nsim_bus_dev)
+		return ERR_PTR(-ENOMEM);
+
+	err = ida_alloc_range(&nsim_bus_dev_ids, id, id, GFP_KERNEL);
+	if (err < 0)
+		goto err_nsim_bus_dev_free;
+	nsim_bus_dev->dev.id = err;
+	nsim_bus_dev->dev.bus = &nsim_bus;
+	nsim_bus_dev->dev.type = &nsim_bus_dev_type;
+	nsim_bus_dev->port_count = port_count;
+
+	err = device_register(&nsim_bus_dev->dev);
+	if (err)
+		goto err_nsim_bus_dev_id_free;
+	return nsim_bus_dev;
+
+err_nsim_bus_dev_id_free:
+	ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id);
+err_nsim_bus_dev_free:
+	kfree(nsim_bus_dev);
+	return ERR_PTR(err);
+}
+
+static void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev)
+{
+	device_unregister(&nsim_bus_dev->dev);
+	ida_free(&nsim_bus_dev_ids, nsim_bus_dev->dev.id);
+	kfree(nsim_bus_dev);
+}
+
+static struct device_driver nsim_driver = {
+	.name		= DRV_NAME,
+	.bus		= &nsim_bus,
+	.owner		= THIS_MODULE,
+};
+
+int nsim_bus_init(void)
+{
+	int err;
+
+	err = bus_register(&nsim_bus);
+	if (err)
+		return err;
+	err = driver_register(&nsim_driver);
+	if (err)
+		goto err_bus_unregister;
+	return 0;
+
+err_bus_unregister:
+	bus_unregister(&nsim_bus);
+	return err;
+}
+
+void nsim_bus_exit(void)
+{
+	struct nsim_bus_dev *nsim_bus_dev, *tmp;
+
+	mutex_lock(&nsim_bus_dev_list_lock);
+	list_for_each_entry_safe(nsim_bus_dev, tmp, &nsim_bus_dev_list, list) {
+		list_del(&nsim_bus_dev->list);
+		nsim_bus_dev_del(nsim_bus_dev);
+	}
+	mutex_unlock(&nsim_bus_dev_list_lock);
+	driver_unregister(&nsim_driver);
+	bus_unregister(&nsim_bus);
+}

drivers/net/netdevsim/devlink.c

-/*
- * Copyright (c) 2018 Cumulus Networks. All rights reserved.
- * Copyright (c) 2018 David Ahern <dsa@cumulusnetworks.com>
- *
- * This software is licensed under the GNU General License Version 2,
- * June 1991 as shown in the file COPYING in the top-level directory of this
- * source tree.
- *
- * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
- * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
- * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
- * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
- * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
- */
-
-#include <linux/device.h>
-#include <net/devlink.h>
-#include <net/netns/generic.h>
-
-#include "netdevsim.h"
-
-static unsigned int nsim_devlink_id;
-
-/* place holder until devlink and namespaces is sorted out */
-static struct net *nsim_devlink_net(struct devlink *devlink)
-{
-	return &init_net;
-}
-
-/* IPv4
- */
-static u64 nsim_ipv4_fib_resource_occ_get(void *priv)
-{
-	struct net *net = priv;
-
-	return nsim_fib_get_val(net, NSIM_RESOURCE_IPV4_FIB, false);
-}
-
-static u64 nsim_ipv4_fib_rules_res_occ_get(void *priv)
-{
-	struct net *net = priv;
-
-	return nsim_fib_get_val(net, NSIM_RESOURCE_IPV4_FIB_RULES, false);
-}
-
-/* IPv6
- */
-static u64 nsim_ipv6_fib_resource_occ_get(void *priv)
-{
-	struct net *net = priv;
-
-	return nsim_fib_get_val(net, NSIM_RESOURCE_IPV6_FIB, false);
-}
-
-static u64 nsim_ipv6_fib_rules_res_occ_get(void *priv)
-{
-	struct net *net = priv;
-
-	return nsim_fib_get_val(net, NSIM_RESOURCE_IPV6_FIB_RULES, false);
-}
-
-static int devlink_resources_register(struct devlink *devlink)
-{
-	struct devlink_resource_size_params params = {
-		.size_max = (u64)-1,
-		.size_granularity = 1,
-		.unit = DEVLINK_RESOURCE_UNIT_ENTRY
-	};
-	struct net *net = nsim_devlink_net(devlink);
-	int err;
-	u64 n;
-
-	/* Resources for IPv4 */
-	err = devlink_resource_register(devlink, "IPv4", (u64)-1,
-					NSIM_RESOURCE_IPV4,
-					DEVLINK_RESOURCE_ID_PARENT_TOP,
-					&params);
-	if (err) {
-		pr_err("Failed to register IPv4 top resource\n");
-		goto out;
-	}
-
-	n = nsim_fib_get_val(net, NSIM_RESOURCE_IPV4_FIB, true);
-	err = devlink_resource_register(devlink, "fib", n,
-					NSIM_RESOURCE_IPV4_FIB,
-					NSIM_RESOURCE_IPV4, &params);
-	if (err) {
-		pr_err("Failed to register IPv4 FIB resource\n");
-		return err;
-	}
-
-	n = nsim_fib_get_val(net, NSIM_RESOURCE_IPV4_FIB_RULES, true);
-	err = devlink_resource_register(devlink, "fib-rules", n,
-					NSIM_RESOURCE_IPV4_FIB_RULES,
-					NSIM_RESOURCE_IPV4, &params);
-	if (err) {
-		pr_err("Failed to register IPv4 FIB rules resource\n");
-		return err;
-	}
-
-	/* Resources for IPv6 */
-	err = devlink_resource_register(devlink, "IPv6", (u64)-1,
-					NSIM_RESOURCE_IPV6,
-					DEVLINK_RESOURCE_ID_PARENT_TOP,
-					&params);
-	if (err) {
-		pr_err("Failed to register IPv6 top resource\n");
-		goto out;
-	}
-
-	n = nsim_fib_get_val(net, NSIM_RESOURCE_IPV6_FIB, true);
-	err = devlink_resource_register(devlink, "fib", n,
-					NSIM_RESOURCE_IPV6_FIB,
-					NSIM_RESOURCE_IPV6, &params);
-	if (err) {
-		pr_err("Failed to register IPv6 FIB resource\n");
-		return err;
-	}
-
-	n = nsim_fib_get_val(net, NSIM_RESOURCE_IPV6_FIB_RULES, true);
-	err = devlink_resource_register(devlink, "fib-rules", n,
-					NSIM_RESOURCE_IPV6_FIB_RULES,
-					NSIM_RESOURCE_IPV6, &params);
-	if (err) {
-		pr_err("Failed to register IPv6 FIB rules resource\n");
-		return err;
-	}
-
-	devlink_resource_occ_get_register(devlink,
-					  NSIM_RESOURCE_IPV4_FIB,
-					  nsim_ipv4_fib_resource_occ_get,
-					  net);
-	devlink_resource_occ_get_register(devlink,
-					  NSIM_RESOURCE_IPV4_FIB_RULES,
-					  nsim_ipv4_fib_rules_res_occ_get,
-					  net);
-	devlink_resource_occ_get_register(devlink,
-					  NSIM_RESOURCE_IPV6_FIB,
-					  nsim_ipv6_fib_resource_occ_get,
-					  net);
-	devlink_resource_occ_get_register(devlink,
-					  NSIM_RESOURCE_IPV6_FIB_RULES,
-					  nsim_ipv6_fib_rules_res_occ_get,
-					  net);
-out:
-	return err;
-}
-
-static int nsim_devlink_reload(struct devlink *devlink,
-			       struct netlink_ext_ack *extack)
-{
-	enum nsim_resource_id res_ids[] = {
-		NSIM_RESOURCE_IPV4_FIB, NSIM_RESOURCE_IPV4_FIB_RULES,
-		NSIM_RESOURCE_IPV6_FIB, NSIM_RESOURCE_IPV6_FIB_RULES
-	};
-	struct net *net = nsim_devlink_net(devlink);
-	int i;
-
-	for (i = 0; i < ARRAY_SIZE(res_ids); ++i) {
-		int err;
-		u64 val;
-
-		err = devlink_resource_size_get(devlink, res_ids[i], &val);
-		if (!err) {
-			err = nsim_fib_set_max(net, res_ids[i], val, extack);
-			if (err)
-				return err;
-		}
-	}
-
-	return 0;
-}
-
-static void nsim_devlink_net_reset(struct net *net)
-{
-	enum nsim_resource_id res_ids[] = {
-		NSIM_RESOURCE_IPV4_FIB, NSIM_RESOURCE_IPV4_FIB_RULES,
-		NSIM_RESOURCE_IPV6_FIB, NSIM_RESOURCE_IPV6_FIB_RULES
-	};
-	int i;
-
-	for (i = 0; i < ARRAY_SIZE(res_ids); ++i) {
-		if (nsim_fib_set_max(net, res_ids[i], (u64)-1, NULL)) {
-			pr_err("Failed to reset limit for resource %u\n",
-			       res_ids[i]);
-		}
-	}
-}
-
-static const struct devlink_ops nsim_devlink_ops = {
-	.reload = nsim_devlink_reload,
-};
-
-/* once devlink / namespace issues are sorted out
- * this needs to be net in which a devlink instance
- * is to be created. e.g., dev_net(ns->netdev)
- */
-static struct net *nsim_to_net(struct netdevsim *ns)
-{
-	return &init_net;
-}
-
-void nsim_devlink_teardown(struct netdevsim *ns)
-{
-	if (ns->devlink) {
-		struct net *net = nsim_to_net(ns);
-		bool *reg_devlink = net_generic(net, nsim_devlink_id);
-
-		devlink_resources_unregister(ns->devlink, NULL);
-		devlink_unregister(ns->devlink);
-		devlink_free(ns->devlink);
-		ns->devlink = NULL;
-
-		nsim_devlink_net_reset(net);
-		*reg_devlink = true;
-	}
-}
-
-int nsim_devlink_setup(struct netdevsim *ns)
-{
-	struct net *net = nsim_to_net(ns);
-	bool *reg_devlink = net_generic(net, nsim_devlink_id);
-	struct devlink *devlink;
-	int err;
-
-	/* only one device per namespace controls devlink */
-	if (!*reg_devlink) {
-		ns->devlink = NULL;
-		return 0;
-	}
-
-	devlink = devlink_alloc(&nsim_devlink_ops, 0);
-	if (!devlink)
-		return -ENOMEM;
-
-	err = devlink_register(devlink, &ns->dev);
-	if (err)
-		goto err_devlink_free;
-
-	err = devlink_resources_register(devlink);
-	if (err)
-		goto err_dl_unregister;
-
-	ns->devlink = devlink;
-
-	*reg_devlink = false;
-
-	return 0;
-
-err_dl_unregister:
-	devlink_unregister(devlink);
-err_devlink_free:
-	devlink_free(devlink);
-
-	return err;
-}
-
-/* Initialize per network namespace state */
-static int __net_init nsim_devlink_netns_init(struct net *net)
-{
-	bool *reg_devlink = net_generic(net, nsim_devlink_id);
-
-	*reg_devlink = true;
-
-	return 0;
-}
-
-static struct pernet_operations nsim_devlink_net_ops = {
-	.init = nsim_devlink_netns_init,
-	.id   = &nsim_devlink_id,
-	.size = sizeof(bool),
-};
-
-void nsim_devlink_exit(void)
-{
-	unregister_pernet_subsys(&nsim_devlink_net_ops);
-	nsim_fib_exit();
-}
-
-int nsim_devlink_init(void)
-{
-	int err;
-
-	err = nsim_fib_init();
-	if (err)
-		goto err_out;
-
-	err = register_pernet_subsys(&nsim_devlink_net_ops);
-	if (err)
-		nsim_fib_exit();
-
-err_out:
-	return err;
-}

drivers/net/netdevsim/fib.c

@@ -18,7 +18,6 @@
 #include <net/ip_fib.h>
 #include <net/ip6_fib.h>
 #include <net/fib_rules.h>
-#include <net/netns/generic.h>
 
 #include "netdevsim.h"
 
@@ -33,15 +32,14 @@ struct nsim_per_fib_data {
 };
 
 struct nsim_fib_data {
+	struct notifier_block fib_nb;
 	struct nsim_per_fib_data ipv4;
 	struct nsim_per_fib_data ipv6;
 };
 
-static unsigned int nsim_fib_net_id;
-
-u64 nsim_fib_get_val(struct net *net, enum nsim_resource_id res_id, bool max)
+u64 nsim_fib_get_val(struct nsim_fib_data *fib_data,
+		     enum nsim_resource_id res_id, bool max)
 {
-	struct nsim_fib_data *fib_data = net_generic(net, nsim_fib_net_id);
 	struct nsim_fib_entry *entry;
 
 	switch (res_id) {
@@ -64,10 +62,10 @@ u64 nsim_fib_get_val(struct net *net, enum nsim_resource_id res_id, bool max)
 	return max ? entry->max : entry->num;
 }
 
-int nsim_fib_set_max(struct net *net, enum nsim_resource_id res_id, u64 val,
+int nsim_fib_set_max(struct nsim_fib_data *fib_data,
+		     enum nsim_resource_id res_id, u64 val,
 		     struct netlink_ext_ack *extack)
 {
-	struct nsim_fib_data *fib_data = net_generic(net, nsim_fib_net_id);
 	struct nsim_fib_entry *entry;
 	int err = 0;
 
@@ -120,9 +118,9 @@ static int nsim_fib_rule_account(struct nsim_fib_entry *entry, bool add,
 	return err;
 }
 
-static int nsim_fib_rule_event(struct fib_notifier_info *info, bool add)
+static int nsim_fib_rule_event(struct nsim_fib_data *data,
+			       struct fib_notifier_info *info, bool add)
 {
-	struct nsim_fib_data *data = net_generic(info->net, nsim_fib_net_id);
 	struct netlink_ext_ack *extack = info->extack;
 	int err = 0;
 
@@ -157,9 +155,9 @@ static int nsim_fib_account(struct nsim_fib_entry *entry, bool add,
 	return err;
 }
 
-static int nsim_fib_event(struct fib_notifier_info *info, bool add)
+static int nsim_fib_event(struct nsim_fib_data *data,
+			  struct fib_notifier_info *info, bool add)
 {
-	struct nsim_fib_data *data = net_generic(info->net, nsim_fib_net_id);
 	struct netlink_ext_ack *extack = info->extack;
 	int err = 0;
 
@@ -178,18 +176,22 @@ static int nsim_fib_event(struct fib_notifier_info *info, bool add)
 static int nsim_fib_event_nb(struct notifier_block *nb, unsigned long event,
 			     void *ptr)
 {
+	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
+						  fib_nb);
 	struct fib_notifier_info *info = ptr;
 	int err = 0;
 
 	switch (event) {
 	case FIB_EVENT_RULE_ADD: /* fall through */
 	case FIB_EVENT_RULE_DEL:
-		err = nsim_fib_rule_event(info, event == FIB_EVENT_RULE_ADD);
+		err = nsim_fib_rule_event(data, info,
+					  event == FIB_EVENT_RULE_ADD);
 		break;
 
 	case FIB_EVENT_ENTRY_ADD:  /* fall through */
 	case FIB_EVENT_ENTRY_DEL:
-		err = nsim_fib_event(info, event == FIB_EVENT_ENTRY_ADD);
+		err = nsim_fib_event(data, info,
+				     event == FIB_EVENT_ENTRY_ADD);
 		break;
 	}
 
@@ -199,30 +201,23 @@ static int nsim_fib_event_nb(struct notifier_block *nb, unsigned long event,
 /* inconsistent dump, trying again */
 static void nsim_fib_dump_inconsistent(struct notifier_block *nb)
 {
-	struct nsim_fib_data *data;
-	struct net *net;
-
-	rcu_read_lock();
-	for_each_net_rcu(net) {
-		data = net_generic(net, nsim_fib_net_id);
+	struct nsim_fib_data *data = container_of(nb, struct nsim_fib_data,
+						  fib_nb);
 
 	data->ipv4.fib.num = 0ULL;
 	data->ipv4.rules.num = 0ULL;
-
 	data->ipv6.fib.num = 0ULL;
 	data->ipv6.rules.num = 0ULL;
-	}
-	rcu_read_unlock();
 }
 
-static struct notifier_block nsim_fib_nb = {
-	.notifier_call = nsim_fib_event_nb,
-};
-
-/* Initialize per network namespace state */
-static int __net_init nsim_fib_netns_init(struct net *net)
+struct nsim_fib_data *nsim_fib_create(void)
 {
-	struct nsim_fib_data *data = net_generic(net, nsim_fib_net_id);
+	struct nsim_fib_data *data;
+	int err;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return ERR_PTR(-ENOMEM);
 
 	data->ipv4.fib.max = (u64)-1;
 	data->ipv4.rules.max = (u64)-1;
@@ -230,37 +225,22 @@ static int __net_init nsim_fib_netns_init(struct net *net)
 	data->ipv6.fib.max = (u64)-1;
 	data->ipv6.rules.max = (u64)-1;
 
-	return 0;
-}
-
-static struct pernet_operations nsim_fib_net_ops = {
-	.init = nsim_fib_netns_init,
-	.id   = &nsim_fib_net_id,
-	.size = sizeof(struct nsim_fib_data),
-};
-
-void nsim_fib_exit(void)
-{
-	unregister_pernet_subsys(&nsim_fib_net_ops);
-	unregister_fib_notifier(&nsim_fib_nb);
-}
-
-int nsim_fib_init(void)
-{
-	int err;
-
-	err = register_pernet_subsys(&nsim_fib_net_ops);
-	if (err < 0) {
-		pr_err("Failed to register pernet subsystem\n");
-		goto err_out;
-	}
-
-	err = register_fib_notifier(&nsim_fib_nb, nsim_fib_dump_inconsistent);
-	if (err < 0) {
+	data->fib_nb.notifier_call = nsim_fib_event_nb;
+	err = register_fib_notifier(&data->fib_nb, nsim_fib_dump_inconsistent);
+	if (err) {
 		pr_err("Failed to register fib notifier\n");
 		goto err_out;
 	}
 
+	return data;
+
 err_out:
-	return err;
+	kfree(data);
+	return ERR_PTR(err);
+}
+
+void nsim_fib_destroy(struct nsim_fib_data *data)
+{
+	unregister_fib_notifier(&data->fib_nb);
+	kfree(data);
 }

drivers/net/netdevsim/ipsec.c

@@ -283,7 +283,8 @@ void nsim_ipsec_init(struct netdevsim *ns)
 	ns->netdev->features |= NSIM_ESP_FEATURES;
 	ns->netdev->hw_enc_features |= NSIM_ESP_FEATURES;
 
-	ns->ipsec.pfile = debugfs_create_file("ipsec", 0400, ns->ddir, ns,
+	ns->ipsec.pfile = debugfs_create_file("ipsec", 0400,
+					      ns->nsim_dev_port->ddir, ns,
 					      &ipsec_dbg_fops);
 }
 

drivers/net/netdevsim/netdevsim.h

@@ -18,6 +18,7 @@
 #include <linux/list.h>
 #include <linux/netdevice.h>
 #include <linux/u64_stats_sync.h>
+#include <net/devlink.h>
 #include <net/xdp.h>
 
 #define DRV_NAME	"netdevsim"
@@ -26,36 +27,6 @@
 
 #define NSIM_EA(extack, msg)	NL_SET_ERR_MSG_MOD((extack), msg)
 
-struct bpf_prog;
-struct bpf_offload_dev;
-struct dentry;
-struct nsim_vf_config;
-
-struct netdevsim_shared_dev {
-	unsigned int refcnt;
-	u32 switch_id;
-
-	struct dentry *ddir;
-
-	struct bpf_offload_dev *bpf_dev;
-
-	bool bpf_bind_accept;
-	u32 bpf_bind_verifier_delay;
-
-	struct dentry *ddir_bpf_bound_progs;
-	u32 prog_id_gen;
-
-	struct list_head bpf_bound_progs;
-	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)
 
@@ -79,18 +50,14 @@ struct nsim_ipsec {
 
 struct netdevsim {
 	struct net_device *netdev;
+	struct nsim_dev *nsim_dev;
+	struct nsim_dev_port *nsim_dev_port;
 
 	u64 tx_packets;
 	u64 tx_bytes;
 	struct u64_stats_sync syncp;
 
-	struct device dev;
-	struct netdevsim_shared_dev *sdev;
-
-	struct dentry *ddir;
-
-	unsigned int num_vfs;
-	struct nsim_vf_config *vfconfigs;
+	struct nsim_bus_dev *nsim_bus_dev;
 
 	struct bpf_prog	*bpf_offloaded;
 	u32 bpf_offloaded_id;
@@ -104,11 +71,16 @@ struct netdevsim {
 	bool bpf_xdpoffload_accept;
 
 	bool bpf_map_accept;
-	struct devlink *devlink;
 	struct nsim_ipsec ipsec;
 };
 
+struct netdevsim *
+nsim_create(struct nsim_dev *nsim_dev, struct nsim_dev_port *nsim_dev_port);
+void nsim_destroy(struct netdevsim *ns);
+
 #ifdef CONFIG_BPF_SYSCALL
+int nsim_bpf_dev_init(struct nsim_dev *nsim_dev);
+void nsim_bpf_dev_exit(struct nsim_dev *nsim_dev);
 int nsim_bpf_init(struct netdevsim *ns);
 void nsim_bpf_uninit(struct netdevsim *ns);
 int nsim_bpf(struct net_device *dev, struct netdev_bpf *bpf);
@@ -116,6 +88,15 @@ int nsim_bpf_disable_tc(struct netdevsim *ns);
 int nsim_bpf_setup_tc_block_cb(enum tc_setup_type type,
 			       void *type_data, void *cb_priv);
 #else
+
+static inline int nsim_bpf_dev_init(struct nsim_dev *nsim_dev)
+{
+	return 0;
+}
+
+static inline void nsim_bpf_dev_exit(struct nsim_dev *nsim_dev)
+{
+}
 static inline int nsim_bpf_init(struct netdevsim *ns)
 {
 	return 0;
@@ -153,16 +134,46 @@ enum nsim_resource_id {
 	NSIM_RESOURCE_IPV6_FIB_RULES,
 };
 
-int nsim_devlink_setup(struct netdevsim *ns);
-void nsim_devlink_teardown(struct netdevsim *ns);
+struct nsim_dev_port {
+	struct list_head list;
+	struct devlink_port devlink_port;
+	unsigned int port_index;
+	struct dentry *ddir;
+	struct netdevsim *ns;
+};
 
-int nsim_devlink_init(void);
-void nsim_devlink_exit(void);
+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;
+	struct dentry *ddir_bpf_bound_progs;
+	u32 prog_id_gen;
+	struct list_head bpf_bound_progs;
+	struct list_head bpf_bound_maps;
+	struct netdev_phys_item_id switch_id;
+	struct list_head port_list;
+	struct mutex port_list_lock; /* protects port list */
+};
 
-int nsim_fib_init(void);
-void nsim_fib_exit(void);
-u64 nsim_fib_get_val(struct net *net, enum nsim_resource_id res_id, bool max);
-int nsim_fib_set_max(struct net *net, enum nsim_resource_id res_id, u64 val,
+int nsim_dev_init(void);
+void nsim_dev_exit(void);
+int nsim_dev_probe(struct nsim_bus_dev *nsim_bus_dev);
+void nsim_dev_remove(struct nsim_bus_dev *nsim_bus_dev);
+int nsim_dev_port_add(struct nsim_bus_dev *nsim_bus_dev,
+		      unsigned int port_index);
+int nsim_dev_port_del(struct nsim_bus_dev *nsim_bus_dev,
+		      unsigned int port_index);
+
+struct nsim_fib_data *nsim_fib_create(void);
+void nsim_fib_destroy(struct nsim_fib_data *fib_data);
+u64 nsim_fib_get_val(struct nsim_fib_data *fib_data,
+		     enum nsim_resource_id res_id, bool max);
+int nsim_fib_set_max(struct nsim_fib_data *fib_data,
+		     enum nsim_resource_id res_id, u64 val,
 		     struct netlink_ext_ack *extack);
 
 #if IS_ENABLED(CONFIG_XFRM_OFFLOAD)
@@ -184,7 +195,26 @@ static inline bool nsim_ipsec_tx(struct netdevsim *ns, struct sk_buff *skb)
 }
 #endif
 
-static inline struct netdevsim *to_nsim(struct device *ptr)
-{
-	return container_of(ptr, struct netdevsim, dev);
-}
+struct nsim_vf_config {
+	int link_state;
+	u16 min_tx_rate;
+	u16 max_tx_rate;
+	u16 vlan;
+	__be16 vlan_proto;
+	u16 qos;
+	u8 vf_mac[ETH_ALEN];
+	bool spoofchk_enabled;
+	bool trusted;
+	bool rss_query_enabled;
+};
+
+struct nsim_bus_dev {
+	struct device dev;
+	struct list_head list;
+	unsigned int port_count;
+	unsigned int num_vfs;
+	struct nsim_vf_config *vfconfigs;
+};
+
+int nsim_bus_init(void);
+void nsim_bus_exit(void);

tools/testing/selftests/net/rtnetlink.sh

@@ -696,9 +696,9 @@ kci_test_ipsec_offload()
 	algo="aead rfc4106(gcm(aes)) 0x3132333435363738393031323334353664636261 128"
 	srcip=192.168.123.3
 	dstip=192.168.123.4
-	dev=simx1
-	sysfsd=/sys/kernel/debug/netdevsim/$dev
+	sysfsd=/sys/kernel/debug/netdevsim/netdevsim0/ports/0/
 	sysfsf=$sysfsd/ipsec
+	sysfsnet=/sys/bus/netdevsim/devices/netdevsim0/net/
 
 	# setup netdevsim since dummydev doesn't have offload support
 	modprobe netdevsim
@@ -708,7 +708,11 @@ kci_test_ipsec_offload()
 		return 1
 	fi
 
-	ip link add $dev type netdevsim
+	echo "0" > /sys/bus/netdevsim/new_device
+	while [ ! -d $sysfsnet ] ; do :; done
+	udevadm settle
+	dev=`ls $sysfsnet`
+
 	ip addr add $srcip dev $dev
 	ip link set $dev up
 	if [ ! -d $sysfsd ] ; then
@@ -781,7 +785,6 @@ EOF
 	fi
 
 	# clean up any leftovers
-	ip link del $dev
 	rmmod netdevsim
 
 	if [ $ret -ne 0 ]; then