#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)
 {
        .release = nsim_bus_dev_release,
 };
 
+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 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);
+
 int nsim_num_vf(struct device *dev)
 {
        struct nsim_bus_dev *nsim_bus_dev = to_nsim_bus_dev(dev);
 static struct bus_type nsim_bus = {
        .name           = DRV_NAME,
        .dev_name       = DRV_NAME,
+       .bus_groups     = nsim_bus_groups,
        .num_vf         = nsim_num_vf,
 };
 
-struct nsim_bus_dev *nsim_bus_dev_new(void)
+struct nsim_bus_dev *nsim_bus_dev_new(unsigned int id, unsigned int port_count)
 {
        struct nsim_bus_dev *nsim_bus_dev;
        int err;
        if (!nsim_bus_dev)
                return ERR_PTR(-ENOMEM);
 
-       err = ida_alloc(&nsim_bus_dev_ids, GFP_KERNEL);
+       err = ida_alloc_range(&nsim_bus_dev_ids,
+                             id == ~0 ? 0 : 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;
 
 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);
 }