tipc: rename and move message reassembly function

[cascardo/linux.git] / net / tipc / msg.c

diff --git a/net/tipc/msg.c b/net/tipc/msg.c
index e525f8c..8be6e94 100644 (file)
--- a/net/tipc/msg.c
+++ b/net/tipc/msg.c
@@ -1,7 +1,7 @@
 /*
  * net/tipc/msg.c: TIPC message header routines
  *
- * Copyright (c) 2000-2006, Ericsson AB
+ * Copyright (c) 2000-2006, 2014, Ericsson AB
  * Copyright (c) 2005, 2010-2011, Wind River Systems
  * All rights reserved.
  *
@@ -99,3 +99,56 @@ int tipc_msg_build(struct tipc_msg *hdr, struct iovec const *msg_sect,
        }
        return dsz;
 }
+
+/* tipc_buf_append(): Append a buffer to the fragment list of another buffer
+ * Let first buffer become head buffer
+ * Returns 1 and sets *buf to headbuf if chain is complete, otherwise 0
+ * Leaves headbuf pointer at NULL if failure
+ */
+int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf)
+{
+       struct sk_buff *head = *headbuf;
+       struct sk_buff *frag = *buf;
+       struct sk_buff *tail;
+       struct tipc_msg *msg = buf_msg(frag);
+       u32 fragid = msg_type(msg);
+       bool headstolen;
+       int delta;
+
+       skb_pull(frag, msg_hdr_sz(msg));
+
+       if (fragid == FIRST_FRAGMENT) {
+               if (head || skb_unclone(frag, GFP_ATOMIC))
+                       goto out_free;
+               head = *headbuf = frag;
+               skb_frag_list_init(head);
+               return 0;
+       }
+       if (!head)
+               goto out_free;
+       tail = TIPC_SKB_CB(head)->tail;
+       if (skb_try_coalesce(head, frag, &headstolen, &delta)) {
+               kfree_skb_partial(frag, headstolen);
+       } else {
+               if (!skb_has_frag_list(head))
+                       skb_shinfo(head)->frag_list = frag;
+               else
+                       tail->next = frag;
+               head->truesize += frag->truesize;
+               head->data_len += frag->len;
+               head->len += frag->len;
+               TIPC_SKB_CB(head)->tail = frag;
+       }
+       if (fragid == LAST_FRAGMENT) {
+               *buf = head;
+               TIPC_SKB_CB(head)->tail = NULL;
+               *headbuf = NULL;
+               return 1;
+       }
+       *buf = NULL;
+       return 0;
+out_free:
+       pr_warn_ratelimited("Unable to build fragment list\n");
+       kfree_skb(*buf);
+       return 0;
+}