| 摘要 |
The invention blends Fiber Channel ("FC") hardware with networking software to produce a network that allows network data to be transferred via direct memory access ("DMA") between two application buffers in computers separated by a network. During boot up, the FC network interface card ("NIC") drivers specify MTUs greater or equal to the segment size to the operating system so that data are not segmented into smaller datagrams during a network data write. During the network write, a first FC NIC sets up the send end of the DMA and sends the network headers of the data to a second FC NIC. The second FC NIC passes the network headers up through the protocol stack. The protocol stack locates and passes the application buffer address to the second FC NIC. The second FC NIC sets up the receive end of the DMA and sends a signal to the first FC NIC to start a buffer-to-buffer DMA transfer of the data. At the end of the buffer-to-buffer DMA transfer, the first FC NIC sends a signal to the second FC NIC indicating the status of the transfer. The first and second FC NICs may treat the entire data transfer as a Small Computer System Interface ("SCSI") disk transaction and use existing SCSI Assist Hardware to reduce the involvement of the host software. |
