6lowpan: move frame allocation code to a separate function

Separate frame allocation routine from data processing function.
This makes code more human readable and easier for understanding.

Signed-off-by: Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 48 insertions, 33 deletions

diff --git a/net/ieee802154/6lowpan.c b/net/ieee802154/6lowpan.c
index 58c8895716ff..ec03626a3114 100644
--- a/net/ieee802154/6lowpan.c
+++ b/net/ieee802154/6lowpan.c
@@ -650,6 +650,53 @@ static void lowpan_fragment_timer_expired(unsigned long entry_addr)
         kfree(entry);
 }
 
+static struct lowpan_fragment *
+lowpan_alloc_new_frame(struct sk_buff *skb, u8 iphc0, u8 len, u8 tag)
+{
+        struct lowpan_fragment *frame;
+
+        frame = kzalloc(sizeof(struct lowpan_fragment),
+                        GFP_ATOMIC);
+        if (!frame)
+                goto frame_err;
+
+        INIT_LIST_HEAD(&frame->list);
+
+        frame->length = (iphc0 & 7) | (len << 3);
+        frame->tag = tag;
+
+        /* allocate buffer for frame assembling */
+        frame->skb = alloc_skb(frame->length +
+                               sizeof(struct ipv6hdr), GFP_ATOMIC);
+
+        if (!frame->skb)
+                goto skb_err;
+
+        frame->skb->priority = skb->priority;
+        frame->skb->dev = skb->dev;
+
+        /* reserve headroom for uncompressed ipv6 header */
+        skb_reserve(frame->skb, sizeof(struct ipv6hdr));
+        skb_put(frame->skb, frame->length);
+
+        init_timer(&frame->timer);
+        /* time out is the same as for ipv6 - 60 sec */
+        frame->timer.expires = jiffies + LOWPAN_FRAG_TIMEOUT;
+        frame->timer.data = (unsigned long)frame;
+        frame->timer.function = lowpan_fragment_timer_expired;
+
+        add_timer(&frame->timer);
+
+        list_add_tail(&frame->list, &lowpan_fragments);
+
+        return frame;
+
+skb_err:
+        kfree(frame);
+frame_err:
+        return NULL;
+}
+
 static int
 lowpan_process_data(struct sk_buff *skb)
 {
@@ -692,41 +739,9 @@ lowpan_process_data(struct sk_buff *skb)
 
                 /* alloc new frame structure */
                 if (!found) {
-                        frame = kzalloc(sizeof(struct lowpan_fragment),
-                                                                GFP_ATOMIC);
+                        frame = lowpan_alloc_new_frame(skb, iphc0, len, tag);
                         if (!frame)
                                 goto unlock_and_drop;
-
-                        INIT_LIST_HEAD(&frame->list);
-
-                        frame->length = (iphc0 & 7) | (len << 3);
-                        frame->tag = tag;
-
-                        /* allocate buffer for frame assembling */
-                        frame->skb = alloc_skb(frame->length +
-                                        sizeof(struct ipv6hdr), GFP_ATOMIC);
-
-                        if (!frame->skb) {
-                                kfree(frame);
-                                goto unlock_and_drop;
-                        }
-
-                        frame->skb->priority = skb->priority;
-                        frame->skb->dev = skb->dev;
-
-                        /* reserve headroom for uncompressed ipv6 header */
-                        skb_reserve(frame->skb, sizeof(struct ipv6hdr));
-                        skb_put(frame->skb, frame->length);
-
-                        init_timer(&frame->timer);
-                        /* time out is the same as for ipv6 - 60 sec */
-                        frame->timer.expires = jiffies + LOWPAN_FRAG_TIMEOUT;
-                        frame->timer.data = (unsigned long)frame;
-                        frame->timer.function = lowpan_fragment_timer_expired;
-
-                        add_timer(&frame->timer);
-
-                        list_add_tail(&frame->list, &lowpan_fragments);
                 }
 
                 if ((iphc0 & LOWPAN_DISPATCH_MASK) == LOWPAN_DISPATCH_FRAG1)