Data transmission method, device and system

Abstract

The invention provides a data transmission method, device and system, which are used for performing DMA data transmission between an I / O device and a plurality of host devices. The method comprises: mapping DMA memory addresses of a plurality of hosts to virtual addresses of a global virtual address space one by one, and obtaining a DMA message carrying DMA virtual addresses and sent by the I / O device; according to corresponding relationships among the DMA virtual addresses, the DMA memory addresses and the hosts, determining the DMA memory addresses corresponding to the DMA virtual addresses and a target host; modifying the DMA virtual addresses in the DMA message to the DMA memory addresses mapped to the DMA virtual addresses; and sending the modified DMA message to the target host. By applying the technical scheme provided by the invention, the DMA data transmission between the I / O device and the plurality of hosts can be realized, so that the utilization rate of the I / O device is increased and the application scene of network transmission is extended.

Description

technical field [0001] The invention relates to the field of data transmission, in particular to a method, device and data transmission system for DMA data transmission between an I / O device and at least one host device. Background technique [0002] In a distributed environment, in order to improve the scalability and utilization of I / O devices, there are often scenarios where multiple hosts share I / O device resources. Multiple hosts share I / O resources, which can improve the overall utilization efficiency of I / O resources, and hosts can dynamically apply for and release resources according to requirements. At the same time, hosts can share I / O resources for data transmission to synchronize data information and status on different hosts. [0003] When the I / O device transmits data, it generally uses a Direct Memory Access (DMA) technology to transfer data on the I / O device, thereby realizing background batch data transmission independent of the CPU. In the DMA operation, ...

AI Technical Summary

Problems solved by technology

[0004] When multiple hosts share the same I / O device, because each host has an independent DMA memory address space, for the I / O device, there will be conflicts between multiple DMA memory address spaces, which will cause DMA operations to fail. conduct

The existing multi-host I / O resource sharing technology cannot effectively solve the problem that multiple hosts jointly access the same I / O device under high-speed connection

For example, in a prior art, although the host can access the externally expanded I / O resources at high speed, it is still in an exclusive state when using the I / O device, that is, an I / O device can only be used by one host at the same time. access

Another example is that in a prior art, although multiple hosts can share the same network I / O device through IP technology, the IP network causes additional performance overhead loss due to network protocol layer processing, and is limited by the network bandwidth. limited, and there is a large delay, so it is not suitable for short-distance high-performance I / O data transmission applications

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