sockmap with strparser need customized read operations to fix copied_seq
error.

Signed-off-by: Jiayuan Chen <mrpre@163.com>
---
 Documentation/networking/strparser.rst | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/Documentation/networking/strparser.rst b/Documentation/networking/strparser.rst
index 6cab1f74ae05..e41c18eee2f4 100644
--- a/Documentation/networking/strparser.rst
+++ b/Documentation/networking/strparser.rst
@@ -112,7 +112,7 @@ Functions
 Callbacks
 =========
 
-There are six callbacks:
+There are seven callbacks:
 
     ::
 
@@ -182,6 +182,15 @@ There are six callbacks:
     the length of the message. skb->len - offset may be greater
     then full_len since strparser does not trim the skb.
 
+    ::
+
+	int (*read_sock)(struct strparser *strp, read_descriptor_t *desc,
+                     sk_read_actor_t recv_actor);
+
+    read_sock is called when the user specify it, allowing for customized
+    read operations. If the callback is not set (NULL in strp_init) native
+    read_sock operation of the socket is used.
+
     ::
 
 	int (*read_sock_done)(struct strparser *strp, int err);
-- 
2.43.5