net_sched: make traffic control network namespace aware

[pandora-kernel.git] / fs / seq_file.c

diff --git a/fs/seq_file.c b/fs/seq_file.c
index f65b16f..e1f437b 100644 (file)
--- a/fs/seq_file.c
+++ b/fs/seq_file.c
@@ -734,7 +734,7 @@ EXPORT_SYMBOL(seq_hlist_start_head);
  * seq_hlist_next - move to the next position of the hlist
  * @v:    the current iterator
  * @head: the head of the hlist
- * @pos:  the current posision
+ * @ppos: the current position
  *
  * Called at seq_file->op->next().
  */
@@ -750,3 +750,74 @@ struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
                return node->next;
 }
 EXPORT_SYMBOL(seq_hlist_next);
+
+/**
+ * seq_hlist_start_rcu - start an iteration of a hlist protected by RCU
+ * @head: the head of the hlist
+ * @pos:  the start position of the sequence
+ *
+ * Called at seq_file->op->start().
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as hlist_add_head_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+struct hlist_node *seq_hlist_start_rcu(struct hlist_head *head,
+                                      loff_t pos)
+{
+       struct hlist_node *node;
+
+       __hlist_for_each_rcu(node, head)
+               if (pos-- == 0)
+                       return node;
+       return NULL;
+}
+EXPORT_SYMBOL(seq_hlist_start_rcu);
+
+/**
+ * seq_hlist_start_head_rcu - start an iteration of a hlist protected by RCU
+ * @head: the head of the hlist
+ * @pos:  the start position of the sequence
+ *
+ * Called at seq_file->op->start(). Call this function if you want to
+ * print a header at the top of the output.
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as hlist_add_head_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+struct hlist_node *seq_hlist_start_head_rcu(struct hlist_head *head,
+                                           loff_t pos)
+{
+       if (!pos)
+               return SEQ_START_TOKEN;
+
+       return seq_hlist_start_rcu(head, pos - 1);
+}
+EXPORT_SYMBOL(seq_hlist_start_head_rcu);
+
+/**
+ * seq_hlist_next_rcu - move to the next position of the hlist protected by RCU
+ * @v:    the current iterator
+ * @head: the head of the hlist
+ * @ppos: the current position
+ *
+ * Called at seq_file->op->next().
+ *
+ * This list-traversal primitive may safely run concurrently with
+ * the _rcu list-mutation primitives such as hlist_add_head_rcu()
+ * as long as the traversal is guarded by rcu_read_lock().
+ */
+struct hlist_node *seq_hlist_next_rcu(void *v,
+                                     struct hlist_head *head,
+                                     loff_t *ppos)
+{
+       struct hlist_node *node = v;
+
+       ++*ppos;
+       if (v == SEQ_START_TOKEN)
+               return rcu_dereference(head->first);
+       else
+               return rcu_dereference(node->next);
+}
+EXPORT_SYMBOL(seq_hlist_next_rcu);