+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;
+}
+