diff options
Diffstat (limited to 'drivers/net/ethernet/sfc/tx.c')
-rw-r--r-- | drivers/net/ethernet/sfc/tx.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/drivers/net/ethernet/sfc/tx.c b/drivers/net/ethernet/sfc/tx.c index 9b225a7769f7..18713436b443 100644 --- a/drivers/net/ethernet/sfc/tx.c +++ b/drivers/net/ethernet/sfc/tx.c @@ -119,6 +119,25 @@ 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 * |