Staging: batman-adv: move skb reassembly of fragmented packets into dedicated function

[firefly-linux-kernel-4.4.55.git] / drivers / staging / batman-adv / unicast.c

diff --git a/drivers/staging/batman-adv/unicast.c b/drivers/staging/batman-adv/unicast.c
index fef8521235f11b64080204286dfe7935ced4f002..57fe2de627a18615ec57bcd63c8bfbecb88d9435 100644 (file)
--- a/drivers/staging/batman-adv/unicast.c
+++ b/drivers/staging/batman-adv/unicast.c
@@ -29,9 +29,9 @@
 #include "hard-interface.h"
 
 
-struct sk_buff *frag_merge_packet(struct list_head *head,
-                                 struct frag_packet_list_entry *tfp,
-                                 struct sk_buff *skb)
+static struct sk_buff *frag_merge_packet(struct list_head *head,
+                                        struct frag_packet_list_entry *tfp,
+                                        struct sk_buff *skb)
 {
        struct unicast_frag_packet *up =
                (struct unicast_frag_packet *)skb->data;
@@ -62,7 +62,7 @@ struct sk_buff *frag_merge_packet(struct list_head *head,
        return skb;
 }
 
-void frag_create_entry(struct list_head *head, struct sk_buff *skb)
+static void frag_create_entry(struct list_head *head, struct sk_buff *skb)
 {
        struct frag_packet_list_entry *tfp;
        struct unicast_frag_packet *up =
@@ -78,7 +78,7 @@ void frag_create_entry(struct list_head *head, struct sk_buff *skb)
        return;
 }
 
-int frag_create_buffer(struct list_head *head)
+static int frag_create_buffer(struct list_head *head)
 {
        int i;
        struct frag_packet_list_entry *tfp;
@@ -99,7 +99,7 @@ int frag_create_buffer(struct list_head *head)
        return 0;
 }
 
-struct frag_packet_list_entry *frag_search_packet(struct list_head *head,
+static struct frag_packet_list_entry *frag_search_packet(struct list_head *head,
                                                 struct unicast_frag_packet *up)
 {
        struct frag_packet_list_entry *tfp;
@@ -152,6 +152,60 @@ void frag_list_free(struct list_head *head)
        return;
 }
 
+/* frag_reassemble_skb():
+ * returns NET_RX_DROP if the operation failed - skb is left intact
+ * returns NET_RX_SUCCESS if the fragment was buffered (skb_new will be NULL)
+ * or the skb could be reassembled (skb_new will point to the new packet and
+ * skb was freed)
+ */
+int frag_reassemble_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
+                       struct sk_buff **new_skb)
+{
+       unsigned long flags;
+       struct orig_node *orig_node;
+       struct frag_packet_list_entry *tmp_frag_entry;
+       int ret = NET_RX_DROP;
+       struct unicast_frag_packet *unicast_packet =
+               (struct unicast_frag_packet *)skb->data;
+
+       *new_skb = NULL;
+       spin_lock_irqsave(&bat_priv->orig_hash_lock, flags);
+       orig_node = ((struct orig_node *)
+                   hash_find(bat_priv->orig_hash, unicast_packet->orig));
+
+       if (!orig_node) {
+               pr_debug("couldn't find originator in orig_hash\n");
+               goto out;
+       }
+
+       orig_node->last_frag_packet = jiffies;
+
+       if (list_empty(&orig_node->frag_list) &&
+           frag_create_buffer(&orig_node->frag_list)) {
+               pr_debug("couldn't create frag buffer\n");
+               goto out;
+       }
+
+       tmp_frag_entry = frag_search_packet(&orig_node->frag_list,
+                                           unicast_packet);
+
+       if (!tmp_frag_entry) {
+               frag_create_entry(&orig_node->frag_list, skb);
+               ret = NET_RX_SUCCESS;
+               goto out;
+       }
+
+       *new_skb = frag_merge_packet(&orig_node->frag_list, tmp_frag_entry,
+                                    skb);
+       /* if not, merge failed */
+       if (*new_skb)
+               ret = NET_RX_SUCCESS;
+out:
+       spin_unlock_irqrestore(&bat_priv->orig_hash_lock, flags);
+
+       return ret;
+}
+
 static int frag_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
                         struct batman_if *batman_if, uint8_t dstaddr[])
 {