netdevsim: add bus attributes to add new and delete devices

Add a way to add new netdevsim device on netdevsim bus and also to
delete existing netdevsim device from the bus. Track the bus devices
in using a list.

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

diff --git a/drivers/net/netdevsim/bus.c b/drivers/net/netdevsim/bus.c
index c50c5ea..c30692f 100644 (file)
--- a/drivers/net/netdevsim/bus.c
+++ b/drivers/net/netdevsim/bus.c
@@ -6,6 +6,8 @@
 #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>
@@ -13,6 +15,8 @@
 #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)
 {
@@ -113,6 +117,83 @@ static struct device_type nsim_bus_dev_type = {
        .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);
@@ -123,10 +204,11 @@ int nsim_num_vf(struct device *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;
@@ -135,12 +217,15 @@ struct nsim_bus_dev *nsim_bus_dev_new(void)
        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;
@@ -185,6 +270,14 @@ err_bus_unregister:
 
 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);
 }

diff --git a/drivers/net/netdevsim/netdev.c b/drivers/net/netdevsim/netdev.c
index 3407b00..37a442f 100644 (file)
--- a/drivers/net/netdevsim/netdev.c
+++ b/drivers/net/netdevsim/netdev.c
@@ -386,7 +386,7 @@ static int nsim_newlink(struct net *src_net, struct net_device *dev,
        if (IS_ERR(ns->sdev))
                return PTR_ERR(ns->sdev);
 
-       ns->nsim_bus_dev = nsim_bus_dev_new();
+       ns->nsim_bus_dev = nsim_bus_dev_new(~0, 0);
        if (IS_ERR(ns->nsim_bus_dev)) {
                err = PTR_ERR(ns->nsim_bus_dev);
                goto err_sdev_put;

diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index 528d1e7..8d61fcb 100644 (file)
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -196,11 +196,13 @@ struct nsim_vf_config {
 
 struct nsim_bus_dev {
        struct device dev;
+       struct list_head list;
+       unsigned int port_count;
        unsigned int num_vfs;
        struct nsim_vf_config *vfconfigs;
 };
 
-struct nsim_bus_dev *nsim_bus_dev_new(void);
+struct nsim_bus_dev *nsim_bus_dev_new(unsigned int id, unsigned int port_count);
 void nsim_bus_dev_del(struct nsim_bus_dev *nsim_bus_dev);
 int nsim_bus_init(void);
 void nsim_bus_exit(void);