+
+ /*
+ * For the allocation we should keep a few things in mind:
+ * 1) 4byte alignment of 802.11 payload
+ *
+ * For (1) we need at most 4 bytes to guarentee the correct
+ * alignment. We are going to optimize the fact that the chance
+ * that the 802.11 header_size % 4 == 2 is much bigger then
+ * anything else. However since we need to move the frame up
+ * to 3 bytes to the front, which means we need to preallocate
+ * 6 bytes.
+ */
+ reserved_size = 6;
+
+ /*
+ * Allocate skbuffer.
+ */
+ skb = dev_alloc_skb(frame_size + reserved_size);