Merge branch 'stable-3.2' into pandora-3.2

[pandora-kernel.git] / drivers / net / ethernet / sfc / tx.c

diff --git a/drivers/net/ethernet/sfc/tx.c b/drivers/net/ethernet/sfc/tx.c
index df88c54..807d515 100644 (file)
--- a/drivers/net/ethernet/sfc/tx.c
+++ b/drivers/net/ethernet/sfc/tx.c
@@ -115,6 +115,25 @@ efx_max_tx_len(struct efx_nic *efx, dma_addr_t dma_addr)
        return len;
 }
 
+unsigned int efx_tx_max_skb_descs(struct efx_nic *efx)
+{
+       /* Header and payload descriptor for each output segment, plus
+        * one for every input fragment boundary within a segment
+        */
+       unsigned int max_descs = EFX_TSO_MAX_SEGS * 2 + MAX_SKB_FRAGS;
+
+       /* Possibly one more per segment for the alignment workaround */
+       if (EFX_WORKAROUND_5391(efx))
+               max_descs += EFX_TSO_MAX_SEGS;
+
+       /* Possibly more for PCIe page boundaries within input fragments */
+       if (PAGE_SIZE > EFX_PAGE_SIZE)
+               max_descs += max_t(unsigned int, MAX_SKB_FRAGS,
+                                  DIV_ROUND_UP(GSO_MAX_SIZE, EFX_PAGE_SIZE));
+
+       return max_descs;
+}
+
 /*
  * Add a socket buffer to a TX queue
  *