struct rte_mbuf *m_src;
/**< source mbuf
* The total size of the input buffer(s) can be retrieved using
- * rte_pktmbuf_data_len(m_src)
+ * rte_pktmbuf_data_len(m_src). The max data size which can fit in a
+ * single mbuf is limited by the uint16_t rte_mbuf.data_len to 64k-1.
+ * If the input data is bigger than this it can be passed to the PMD in
+ * a chain of mbufs if the PMD's capabilities indicate it supports this.
*/
struct rte_mbuf *m_dst;
/**< destination mbuf
* The total size of the output buffer(s) can be retrieved using
- * rte_pktmbuf_data_len(m_dst)
+ * rte_pktmbuf_data_len(m_dst). The max data size which can fit in a
+ * single mbuf is limited by the uint16_t rte_mbuf.data_len to 64k-1.
+ * If the output data is expected to be bigger than this a chain of
+ * mbufs can be passed to the PMD if the PMD's capabilities indicate
+ * it supports this.
*/
struct {