rt2x00: Align RX descriptor to 4 bytes

[cascardo/linux.git] / drivers / net / wireless / rt2x00 / rt2x00usb.c

diff --git a/drivers/net/wireless/rt2x00/rt2x00usb.c b/drivers/net/wireless/rt2x00/rt2x00usb.c
index 063b167..512ff39 100644 (file)
--- a/drivers/net/wireless/rt2x00/rt2x00usb.c
+++ b/drivers/net/wireless/rt2x00/rt2x00usb.c
@@ -247,11 +247,11 @@ static struct sk_buff* rt2x00usb_alloc_rxskb(struct data_queue *queue)
         * advance.
         */
        frame_size = queue->data_size + queue->desc_size;
-       skb = dev_alloc_skb(frame_size + 2);
+       skb = dev_alloc_skb(queue->desc_size + frame_size + 2);
        if (!skb)
                return NULL;
 
-       skb_reserve(skb, 2);
+       skb_reserve(skb, queue->desc_size + 2);
        skb_put(skb, frame_size);
 
        return skb;
@@ -264,6 +264,7 @@ static void rt2x00usb_interrupt_rxdone(struct urb *urb)
        struct sk_buff *skb;
        struct skb_frame_desc *skbdesc;
        struct rxdone_entry_desc rxdesc;
+       int header_size;
 
        if (!test_bit(DEVICE_ENABLED_RADIO, &rt2x00dev->flags) ||
            !test_and_clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags))
@@ -287,6 +288,18 @@ static void rt2x00usb_interrupt_rxdone(struct urb *urb)
        memset(&rxdesc, 0, sizeof(rxdesc));
        rt2x00dev->ops->lib->fill_rxdone(entry, &rxdesc);
 
+       /*
+        * The data behind the ieee80211 header must be
+        * aligned on a 4 byte boundary.
+        */
+       header_size = ieee80211_get_hdrlen_from_skb(entry->skb);
+       if (header_size % 4 == 0) {
+               skb_push(entry->skb, 2);
+               memmove(entry->skb->data, entry->skb->data + 2,
+                       entry->skb->len - 2);
+               skbdesc->data = entry->skb->data;
+       }
+
        /*
         * Allocate a new sk buffer to replace the current one.
         * If allocation fails, we should drop the current frame