seq_file: Add helpers for iteration over a hlist

Some places in kernel need to iterate over a hlist in seq_file,
so provide some common helpers.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 0 deletions

diff --git a/include/linux/seq_file.h b/include/linux/seq_file.h
index 8366d8f12e53..c95bcdc18f4c 100644
--- a/include/linux/seq_file.h
+++ b/include/linux/seq_file.h
@@ -135,4 +135,15 @@ extern struct list_head *seq_list_start_head(struct list_head *head,
 extern struct list_head *seq_list_next(void *v, struct list_head *head,
                 loff_t *ppos);
 
+/*
+ * Helpers for iteration over hlist_head-s in seq_files
+ */
+
+extern struct hlist_node *seq_hlist_start(struct hlist_head *head,
+                loff_t pos);
+extern struct hlist_node *seq_hlist_start_head(struct hlist_head *head,
+                loff_t pos);
+extern struct hlist_node *seq_hlist_next(void *v, struct hlist_head *head,
+                loff_t *ppos);
+
 #endif