gianfar: fix undo of reserve()

Fix undo of reserve() before RX recycle

gfar_new_skb reserve()s space in the SKB to align it.  If an error occurs,
and the skb needs to be returned to the RX recycle queue, the current code
attempts to reset head, but did not reset tail.  This patch remembers the
alignment amount, and reverses the reserve() when needed.

Signed-off-by: Ben Menchaca <ben@bigfootnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/drivers/net/gianfar.h b/drivers/net/gianfar.h
index 3d72dc43dca5..17d25e714236 100644
--- a/drivers/net/gianfar.h
+++ b/drivers/net/gianfar.h
@@ -566,6 +566,12 @@ struct rxfcb {
         u16     vlctl;  /* VLAN control word */
 };
 
+struct gianfar_skb_cb {
+        int alignamount;
+};
+
+#define GFAR_CB(skb) ((struct gianfar_skb_cb *)((skb)->cb))
+
 struct rmon_mib
 {
         u32     tr64;   /* 0x.680 - Transmit and Receive 64-byte Frame Counter */