+/**
+ * @brief Copy buffer to tx ring
+ *
+ * @param * vm (in)
+ * @param * node (in)
+ * @param * mif (in) pointer to memif interface
+ * @param bi (in) vlib buffer index
+ * @param * ring (in) pointer to memif ring
+ * @param * head (in/out) ring head
+ * @param mask (in) ring size - 1
+ */
+static_always_inline void
+memif_copy_buffer_to_tx_ring (vlib_main_t * vm, vlib_node_runtime_t * node,
+ memif_if_t * mif, u32 bi, memif_ring_t * ring,
+ u16 * head, u16 mask)
+{
+ vlib_buffer_t *b0;
+ void *mb0;
+ u32 total = 0, len;
+
+ mb0 = memif_get_buffer (mif, ring, *head);
+ ring->desc[*head].flags = 0;
+ do
+ {
+ b0 = vlib_get_buffer (vm, bi);
+ len = b0->current_length;
+ if (PREDICT_FALSE (ring->desc[*head].buffer_length < (total + len)))
+ {
+ if (PREDICT_TRUE (total))
+ {
+ ring->desc[*head].length = total;
+ total = 0;
+ ring->desc[*head].flags |= MEMIF_DESC_FLAG_NEXT;
+ *head = (*head + 1) & mask;
+ mb0 = memif_get_buffer (mif, ring, *head);
+ ring->desc[*head].flags = 0;
+ }
+ }
+ if (PREDICT_TRUE (ring->desc[*head].buffer_length >= (total + len)))
+ {
+ clib_memcpy (mb0 + total, vlib_buffer_get_current (b0),
+ CLIB_CACHE_LINE_BYTES);
+ if (len > CLIB_CACHE_LINE_BYTES)
+ clib_memcpy (mb0 + CLIB_CACHE_LINE_BYTES + total,
+ vlib_buffer_get_current (b0) + CLIB_CACHE_LINE_BYTES,
+ len - CLIB_CACHE_LINE_BYTES);
+ total += len;
+ }
+ else
+ {
+ vlib_error_count (vm, node->node_index, MEMIF_TX_ERROR_TRUNC_PACKET,
+ 1);
+ break;
+ }
+ }
+ while ((bi = (b0->flags & VLIB_BUFFER_NEXT_PRESENT) ? b0->next_buffer : 0));
+
+ if (PREDICT_TRUE (total))
+ {
+ ring->desc[*head].length = total;
+ *head = (*head + 1) & mask;
+ }
+}
+