Make em(4) handle too many fragmented frame with m_defrag(9).

Previously em(4) requeued the failed mbuf chains from
bus_dmamap_load_mbuf_sg(9) failure to resend it later. However,
bus_dmamap_load_mbuf_sg(9) may never complete its request as the
fragmented frames can have more than EM_MAX_SCATTER segments.
To handle the above EFBIG case, defragment the frame with m_defrag(9)
and free the mbuf chain if it can't deframent the chain due to
resource shortage.

Reviewed by	glebius (with improvements)

0 files changed, 0 insertions, 0 deletions