net: add a possibility to get private from netdev_adjacent->list
[firefly-linux-kernel-4.4.55.git] / net / core / dev.c
index 5c713f2239cc6245d230d2e35e243bbee7339761..acc11810805f251c57cff9244b5199b8fc2de0db 100644 (file)
@@ -4373,42 +4373,40 @@ struct netdev_adjacent {
        /* upper master flag, there can only be one master device per list */
        bool master;
 
-       /* indicates that this dev is our first-level lower/upper device */
-       bool neighbour;
-
        /* counter for the number of times this device was added to us */
        u16 ref_nr;
 
+       /* private field for the users */
+       void *private;
+
        struct list_head list;
        struct rcu_head rcu;
 };
 
-static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
-                                                struct net_device *adj_dev,
-                                                bool upper)
+static struct netdev_adjacent *__netdev_find_adj_rcu(struct net_device *dev,
+                                                    struct net_device *adj_dev,
+                                                    struct list_head *adj_list)
 {
        struct netdev_adjacent *adj;
-       struct list_head *dev_list;
 
-       dev_list = upper ? &dev->upper_dev_list : &dev->lower_dev_list;
-
-       list_for_each_entry(adj, dev_list, list) {
+       list_for_each_entry_rcu(adj, adj_list, list) {
                if (adj->dev == adj_dev)
                        return adj;
        }
        return NULL;
 }
 
-static inline struct netdev_adjacent *__netdev_find_upper(struct net_device *dev,
-                                                         struct net_device *udev)
+static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
+                                                struct net_device *adj_dev,
+                                                struct list_head *adj_list)
 {
-       return __netdev_find_adj(dev, udev, true);
-}
+       struct netdev_adjacent *adj;
 
-static inline struct netdev_adjacent *__netdev_find_lower(struct net_device *dev,
-                                                         struct net_device *ldev)
-{
-       return __netdev_find_adj(dev, ldev, false);
+       list_for_each_entry(adj, adj_list, list) {
+               if (adj->dev == adj_dev)
+                       return adj;
+       }
+       return NULL;
 }
 
 /**
@@ -4425,7 +4423,7 @@ bool netdev_has_upper_dev(struct net_device *dev,
 {
        ASSERT_RTNL();
 
-       return __netdev_find_upper(dev, upper_dev);
+       return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
 }
 EXPORT_SYMBOL(netdev_has_upper_dev);
 
@@ -4440,7 +4438,7 @@ bool netdev_has_any_upper_dev(struct net_device *dev)
 {
        ASSERT_RTNL();
 
-       return !list_empty(&dev->upper_dev_list);
+       return !list_empty(&dev->all_adj_list.upper);
 }
 EXPORT_SYMBOL(netdev_has_any_upper_dev);
 
@@ -4457,10 +4455,10 @@ struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
 
        ASSERT_RTNL();
 
-       if (list_empty(&dev->upper_dev_list))
+       if (list_empty(&dev->adj_list.upper))
                return NULL;
 
-       upper = list_first_entry(&dev->upper_dev_list,
+       upper = list_first_entry(&dev->adj_list.upper,
                                 struct netdev_adjacent, list);
        if (likely(upper->master))
                return upper->dev;
@@ -4468,15 +4466,26 @@ struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
 }
 EXPORT_SYMBOL(netdev_master_upper_dev_get);
 
-/* netdev_upper_get_next_dev_rcu - Get the next dev from upper list
+void *netdev_adjacent_get_private(struct list_head *adj_list)
+{
+       struct netdev_adjacent *adj;
+
+       adj = list_entry(adj_list, struct netdev_adjacent, list);
+
+       return adj->private;
+}
+EXPORT_SYMBOL(netdev_adjacent_get_private);
+
+/**
+ * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
  * @dev: device
  * @iter: list_head ** of the current position
  *
  * Gets the next device from the dev's upper list, starting from iter
  * position. The caller must hold RCU read lock.
  */
-struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
-                                                struct list_head **iter)
+struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
+                                                    struct list_head **iter)
 {
        struct netdev_adjacent *upper;
 
@@ -4484,14 +4493,71 @@ struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
 
        upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
 
-       if (&upper->list == &dev->upper_dev_list)
+       if (&upper->list == &dev->all_adj_list.upper)
                return NULL;
 
        *iter = &upper->list;
 
        return upper->dev;
 }
-EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
+EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
+
+/**
+ * netdev_lower_get_next_private - Get the next ->private from the
+ *                                lower neighbour list
+ * @dev: device
+ * @iter: list_head ** of the current position
+ *
+ * Gets the next netdev_adjacent->private from the dev's lower neighbour
+ * list, starting from iter position. The caller must hold either hold the
+ * RTNL lock or its own locking that guarantees that the neighbour lower
+ * list will remain unchainged.
+ */
+void *netdev_lower_get_next_private(struct net_device *dev,
+                                   struct list_head **iter)
+{
+       struct netdev_adjacent *lower;
+
+       lower = list_entry(*iter, struct netdev_adjacent, list);
+
+       if (&lower->list == &dev->adj_list.lower)
+               return NULL;
+
+       if (iter)
+               *iter = lower->list.next;
+
+       return lower->private;
+}
+EXPORT_SYMBOL(netdev_lower_get_next_private);
+
+/**
+ * netdev_lower_get_next_private_rcu - Get the next ->private from the
+ *                                    lower neighbour list, RCU
+ *                                    variant
+ * @dev: device
+ * @iter: list_head ** of the current position
+ *
+ * Gets the next netdev_adjacent->private from the dev's lower neighbour
+ * list, starting from iter position. The caller must hold RCU read lock.
+ */
+void *netdev_lower_get_next_private_rcu(struct net_device *dev,
+                                       struct list_head **iter)
+{
+       struct netdev_adjacent *lower;
+
+       WARN_ON_ONCE(!rcu_read_lock_held());
+
+       lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
+
+       if (&lower->list == &dev->adj_list.lower)
+               return NULL;
+
+       if (iter)
+               *iter = &lower->list;
+
+       return lower->private;
+}
+EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
 
 /**
  * netdev_master_upper_dev_get_rcu - Get master upper device
@@ -4504,7 +4570,7 @@ struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
 {
        struct netdev_adjacent *upper;
 
-       upper = list_first_or_null_rcu(&dev->upper_dev_list,
+       upper = list_first_or_null_rcu(&dev->adj_list.upper,
                                       struct netdev_adjacent, list);
        if (upper && likely(upper->master))
                return upper->dev;
@@ -4514,15 +4580,14 @@ EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
 
 static int __netdev_adjacent_dev_insert(struct net_device *dev,
                                        struct net_device *adj_dev,
-                                       bool neighbour, bool master,
-                                       bool upper)
+                                       struct list_head *dev_list,
+                                       void *private, bool master)
 {
        struct netdev_adjacent *adj;
 
-       adj = __netdev_find_adj(dev, adj_dev, upper);
+       adj = __netdev_find_adj(dev, adj_dev, dev_list);
 
        if (adj) {
-               BUG_ON(neighbour);
                adj->ref_nr++;
                return 0;
        }
@@ -4533,124 +4598,132 @@ static int __netdev_adjacent_dev_insert(struct net_device *dev,
 
        adj->dev = adj_dev;
        adj->master = master;
-       adj->neighbour = neighbour;
        adj->ref_nr = 1;
-
+       adj->private = private;
        dev_hold(adj_dev);
-       pr_debug("dev_hold for %s, because of %s link added from %s to %s\n",
-                adj_dev->name, upper ? "upper" : "lower", dev->name,
-                adj_dev->name);
 
-       if (!upper) {
-               list_add_tail_rcu(&adj->list, &dev->lower_dev_list);
-               return 0;
-       }
+       pr_debug("dev_hold for %s, because of link added from %s to %s\n",
+                adj_dev->name, dev->name, adj_dev->name);
 
-       /* Ensure that master upper link is always the first item in list. */
+       /* Ensure that master link is always the first item in list. */
        if (master)
-               list_add_rcu(&adj->list, &dev->upper_dev_list);
+               list_add_rcu(&adj->list, dev_list);
        else
-               list_add_tail_rcu(&adj->list, &dev->upper_dev_list);
+               list_add_tail_rcu(&adj->list, dev_list);
 
        return 0;
 }
 
-static inline int __netdev_upper_dev_insert(struct net_device *dev,
-                                           struct net_device *udev,
-                                           bool master, bool neighbour)
-{
-       return __netdev_adjacent_dev_insert(dev, udev, neighbour, master,
-                                           true);
-}
-
-static inline int __netdev_lower_dev_insert(struct net_device *dev,
-                                           struct net_device *ldev,
-                                           bool neighbour)
-{
-       return __netdev_adjacent_dev_insert(dev, ldev, neighbour, false,
-                                           false);
-}
-
 void __netdev_adjacent_dev_remove(struct net_device *dev,
-                                 struct net_device *adj_dev, bool upper)
+                                 struct net_device *adj_dev,
+                                 struct list_head *dev_list)
 {
        struct netdev_adjacent *adj;
 
-       if (upper)
-               adj = __netdev_find_upper(dev, adj_dev);
-       else
-               adj = __netdev_find_lower(dev, adj_dev);
+       adj = __netdev_find_adj(dev, adj_dev, dev_list);
 
-       if (!adj)
+       if (!adj) {
+               pr_err("tried to remove device %s from %s\n",
+                      dev->name, adj_dev->name);
                BUG();
+       }
 
        if (adj->ref_nr > 1) {
+               pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
+                        adj->ref_nr-1);
                adj->ref_nr--;
                return;
        }
 
        list_del_rcu(&adj->list);
-       pr_debug("dev_put for %s, because of %s link removed from %s to %s\n",
-                adj_dev->name, upper ? "upper" : "lower", dev->name,
-                adj_dev->name);
+       pr_debug("dev_put for %s, because link removed from %s to %s\n",
+                adj_dev->name, dev->name, adj_dev->name);
        dev_put(adj_dev);
        kfree_rcu(adj, rcu);
 }
 
-static inline void __netdev_upper_dev_remove(struct net_device *dev,
-                                            struct net_device *udev)
-{
-       return __netdev_adjacent_dev_remove(dev, udev, true);
-}
-
-static inline void __netdev_lower_dev_remove(struct net_device *dev,
-                                            struct net_device *ldev)
-{
-       return __netdev_adjacent_dev_remove(dev, ldev, false);
-}
-
-int __netdev_adjacent_dev_insert_link(struct net_device *dev,
-                                     struct net_device *upper_dev,
-                                     bool master, bool neighbour)
+int __netdev_adjacent_dev_link_lists(struct net_device *dev,
+                                    struct net_device *upper_dev,
+                                    struct list_head *up_list,
+                                    struct list_head *down_list,
+                                    void *private, bool master)
 {
        int ret;
 
-       ret = __netdev_upper_dev_insert(dev, upper_dev, master, neighbour);
+       ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
+                                          master);
        if (ret)
                return ret;
 
-       ret = __netdev_lower_dev_insert(upper_dev, dev, neighbour);
+       ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
+                                          false);
        if (ret) {
-               __netdev_upper_dev_remove(dev, upper_dev);
+               __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
                return ret;
        }
 
        return 0;
 }
 
-static inline int __netdev_adjacent_dev_link(struct net_device *dev,
-                                            struct net_device *udev)
+int __netdev_adjacent_dev_link(struct net_device *dev,
+                              struct net_device *upper_dev)
 {
-       return __netdev_adjacent_dev_insert_link(dev, udev, false, false);
+       return __netdev_adjacent_dev_link_lists(dev, upper_dev,
+                                               &dev->all_adj_list.upper,
+                                               &upper_dev->all_adj_list.lower,
+                                               NULL, false);
 }
 
-static inline int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
-                                                      struct net_device *udev,
-                                                      bool master)
+void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
+                                       struct net_device *upper_dev,
+                                       struct list_head *up_list,
+                                       struct list_head *down_list)
 {
-       return __netdev_adjacent_dev_insert_link(dev, udev, master, true);
+       __netdev_adjacent_dev_remove(dev, upper_dev, up_list);
+       __netdev_adjacent_dev_remove(upper_dev, dev, down_list);
 }
 
 void __netdev_adjacent_dev_unlink(struct net_device *dev,
                                  struct net_device *upper_dev)
 {
-       __netdev_upper_dev_remove(dev, upper_dev);
-       __netdev_lower_dev_remove(upper_dev, dev);
+       __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
+                                          &dev->all_adj_list.upper,
+                                          &upper_dev->all_adj_list.lower);
+}
+
+int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
+                                        struct net_device *upper_dev,
+                                        void *private, bool master)
+{
+       int ret = __netdev_adjacent_dev_link(dev, upper_dev);
+
+       if (ret)
+               return ret;
+
+       ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
+                                              &dev->adj_list.upper,
+                                              &upper_dev->adj_list.lower,
+                                              private, master);
+       if (ret) {
+               __netdev_adjacent_dev_unlink(dev, upper_dev);
+               return ret;
+       }
+
+       return 0;
 }
 
+void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
+                                           struct net_device *upper_dev)
+{
+       __netdev_adjacent_dev_unlink(dev, upper_dev);
+       __netdev_adjacent_dev_unlink_lists(dev, upper_dev,
+                                          &dev->adj_list.upper,
+                                          &upper_dev->adj_list.lower);
+}
 
 static int __netdev_upper_dev_link(struct net_device *dev,
-                                  struct net_device *upper_dev, bool master)
+                                  struct net_device *upper_dev, bool master,
+                                  void *private)
 {
        struct netdev_adjacent *i, *j, *to_i, *to_j;
        int ret = 0;
@@ -4661,26 +4734,29 @@ static int __netdev_upper_dev_link(struct net_device *dev,
                return -EBUSY;
 
        /* To prevent loops, check if dev is not upper device to upper_dev. */
-       if (__netdev_find_upper(upper_dev, dev))
+       if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
                return -EBUSY;
 
-       if (__netdev_find_upper(dev, upper_dev))
+       if (__netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper))
                return -EEXIST;
 
        if (master && netdev_master_upper_dev_get(dev))
                return -EBUSY;
 
-       ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, master);
+       ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
+                                                  master);
        if (ret)
                return ret;
 
        /* Now that we linked these devs, make all the upper_dev's
-        * upper_dev_list visible to every dev's lower_dev_list and vice
+        * all_adj_list.upper visible to every dev's all_adj_list.lower an
         * versa, and don't forget the devices itself. All of these
         * links are non-neighbours.
         */
-       list_for_each_entry(i, &dev->lower_dev_list, list) {
-               list_for_each_entry(j, &upper_dev->upper_dev_list, list) {
+       list_for_each_entry(i, &dev->all_adj_list.lower, list) {
+               list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
+                       pr_debug("Interlinking %s with %s, non-neighbour\n",
+                                i->dev->name, j->dev->name);
                        ret = __netdev_adjacent_dev_link(i->dev, j->dev);
                        if (ret)
                                goto rollback_mesh;
@@ -4688,14 +4764,18 @@ static int __netdev_upper_dev_link(struct net_device *dev,
        }
 
        /* add dev to every upper_dev's upper device */
-       list_for_each_entry(i, &upper_dev->upper_dev_list, list) {
+       list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
+               pr_debug("linking %s's upper device %s with %s\n",
+                        upper_dev->name, i->dev->name, dev->name);
                ret = __netdev_adjacent_dev_link(dev, i->dev);
                if (ret)
                        goto rollback_upper_mesh;
        }
 
        /* add upper_dev to every dev's lower device */
-       list_for_each_entry(i, &dev->lower_dev_list, list) {
+       list_for_each_entry(i, &dev->all_adj_list.lower, list) {
+               pr_debug("linking %s's lower device %s with %s\n", dev->name,
+                        i->dev->name, upper_dev->name);
                ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
                if (ret)
                        goto rollback_lower_mesh;
@@ -4706,7 +4786,7 @@ static int __netdev_upper_dev_link(struct net_device *dev,
 
 rollback_lower_mesh:
        to_i = i;
-       list_for_each_entry(i, &dev->lower_dev_list, list) {
+       list_for_each_entry(i, &dev->all_adj_list.lower, list) {
                if (i == to_i)
                        break;
                __netdev_adjacent_dev_unlink(i->dev, upper_dev);
@@ -4716,7 +4796,7 @@ rollback_lower_mesh:
 
 rollback_upper_mesh:
        to_i = i;
-       list_for_each_entry(i, &upper_dev->upper_dev_list, list) {
+       list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
                if (i == to_i)
                        break;
                __netdev_adjacent_dev_unlink(dev, i->dev);
@@ -4727,8 +4807,8 @@ rollback_upper_mesh:
 rollback_mesh:
        to_i = i;
        to_j = j;
-       list_for_each_entry(i, &dev->lower_dev_list, list) {
-               list_for_each_entry(j, &upper_dev->upper_dev_list, list) {
+       list_for_each_entry(i, &dev->all_adj_list.lower, list) {
+               list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
                        if (i == to_i && j == to_j)
                                break;
                        __netdev_adjacent_dev_unlink(i->dev, j->dev);
@@ -4737,7 +4817,7 @@ rollback_mesh:
                        break;
        }
 
-       __netdev_adjacent_dev_unlink(dev, upper_dev);
+       __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
 
        return ret;
 }
@@ -4755,7 +4835,7 @@ rollback_mesh:
 int netdev_upper_dev_link(struct net_device *dev,
                          struct net_device *upper_dev)
 {
-       return __netdev_upper_dev_link(dev, upper_dev, false);
+       return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
 }
 EXPORT_SYMBOL(netdev_upper_dev_link);
 
@@ -4773,10 +4853,18 @@ EXPORT_SYMBOL(netdev_upper_dev_link);
 int netdev_master_upper_dev_link(struct net_device *dev,
                                 struct net_device *upper_dev)
 {
-       return __netdev_upper_dev_link(dev, upper_dev, true);
+       return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
 }
 EXPORT_SYMBOL(netdev_master_upper_dev_link);
 
+int netdev_master_upper_dev_link_private(struct net_device *dev,
+                                        struct net_device *upper_dev,
+                                        void *private)
+{
+       return __netdev_upper_dev_link(dev, upper_dev, true, private);
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
+
 /**
  * netdev_upper_dev_unlink - Removes a link to upper device
  * @dev: device
@@ -4791,29 +4879,59 @@ void netdev_upper_dev_unlink(struct net_device *dev,
        struct netdev_adjacent *i, *j;
        ASSERT_RTNL();
 
-       __netdev_adjacent_dev_unlink(dev, upper_dev);
+       __netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
 
        /* Here is the tricky part. We must remove all dev's lower
         * devices from all upper_dev's upper devices and vice
         * versa, to maintain the graph relationship.
         */
-       list_for_each_entry(i, &dev->lower_dev_list, list)
-               list_for_each_entry(j, &upper_dev->upper_dev_list, list)
+       list_for_each_entry(i, &dev->all_adj_list.lower, list)
+               list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
                        __netdev_adjacent_dev_unlink(i->dev, j->dev);
 
        /* remove also the devices itself from lower/upper device
         * list
         */
-       list_for_each_entry(i, &dev->lower_dev_list, list)
+       list_for_each_entry(i, &dev->all_adj_list.lower, list)
                __netdev_adjacent_dev_unlink(i->dev, upper_dev);
 
-       list_for_each_entry(i, &upper_dev->upper_dev_list, list)
+       list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
                __netdev_adjacent_dev_unlink(dev, i->dev);
 
        call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
 }
 EXPORT_SYMBOL(netdev_upper_dev_unlink);
 
+void *netdev_lower_dev_get_private_rcu(struct net_device *dev,
+                                      struct net_device *lower_dev)
+{
+       struct netdev_adjacent *lower;
+
+       if (!lower_dev)
+               return NULL;
+       lower = __netdev_find_adj_rcu(dev, lower_dev, &dev->adj_list.lower);
+       if (!lower)
+               return NULL;
+
+       return lower->private;
+}
+EXPORT_SYMBOL(netdev_lower_dev_get_private_rcu);
+
+void *netdev_lower_dev_get_private(struct net_device *dev,
+                                  struct net_device *lower_dev)
+{
+       struct netdev_adjacent *lower;
+
+       if (!lower_dev)
+               return NULL;
+       lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
+       if (!lower)
+               return NULL;
+
+       return lower->private;
+}
+EXPORT_SYMBOL(netdev_lower_dev_get_private);
+
 static void dev_change_rx_flags(struct net_device *dev, int flags)
 {
        const struct net_device_ops *ops = dev->netdev_ops;
@@ -6069,8 +6187,10 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
        INIT_LIST_HEAD(&dev->napi_list);
        INIT_LIST_HEAD(&dev->unreg_list);
        INIT_LIST_HEAD(&dev->link_watch_list);
-       INIT_LIST_HEAD(&dev->upper_dev_list);
-       INIT_LIST_HEAD(&dev->lower_dev_list);
+       INIT_LIST_HEAD(&dev->adj_list.upper);
+       INIT_LIST_HEAD(&dev->adj_list.lower);
+       INIT_LIST_HEAD(&dev->all_adj_list.upper);
+       INIT_LIST_HEAD(&dev->all_adj_list.lower);
        dev->priv_flags = IFF_XMIT_DST_RELEASE;
        setup(dev);