Protocol translation in a data storage system

1. A data storage system comprising:

an input/output server including a processor, memory, and a host channel adapter;

a storage unit including a processor, memory, and a storage module;

the storage module including a storage controller, and an interface block for connecting the storage module to a corresponding memory-mapped interface;

the storage unit further including a host channel adaptor for connecting the storage unit to the input/output server, the storage unit host channel adapter being connected to a corresponding memory-mapped interface, the storage unit host channel adapter being capable of remote direct memory access to the input/output server; and

protocol translation logic configured to intercept a memory access request from the storage controller, and initiate a corresponding remote direct memory access to the input/output server through the storage unit host channel adapter and the input/output server host channel adapter;

wherein the data storage system is configured to:

establish a network connection between the host channel adapter of the input/output server and the host channel adapter of the storage unit;

write a command header and associated command table to the memory of the input/output server;

deliver the command header to the protocol translation logic, which stores the command header;

read the command header, by the storage controller, from the protocol translation logic;

request, from the storage controller, to read, from the memory of the input/output server, a command at the beginning of the command table pointed to by the command header;

intercept the read request from the storage controller, with the protocol translation logic; and

initiate, with the protocol translation logic, a corresponding remote direct memory access to the input/output server through the host channel adapter of the storage unit and the host channel adapter of the input/output server.

2. The system of claim 1 wherein the storage controller comprises a non-volatile memory host controller interface (NVMHCI) controller.

3. The system of claim 1 wherein the interface block connects the storage module to a corresponding PCI-Express interface.

4. The system of claim 1 wherein the host channel adapter of the storage unit is connected to a corresponding PCI-Express interface.

5. The system of claim 1 wherein the host channel adapter of the storage unit is an InfiniBand host channel adaptor.

6. The system of claim 1 wherein the protocol translation logic comprises a circuit connecting the storage controller to the interface block.

7. The system of claim 1 wherein the protocol translation logic comprises a protocol translation device including an interface block for connecting to a corresponding memory-mapped interface.

8. The system of claim 1 wherein the data storage system is further configured to:

receive, at the storage controller, a write command;

request, from the storage controller, to read, from the memory of the input/output server, the write data;

intercept the read request from the storage controller, with the protocol translation logic; and

initiate, with the protocol translation logic, a corresponding remote direct memory access to the input/output server through the host channel adapter of the storage unit and the host channel adapter of the input/output server.

9. The system of claim 1 wherein the data storage system is further configured to:

receive, at the storage controller, a read command;

request, from the storage controller, to write, from the memory of the input/output server, the read data;

intercept the write request from the storage controller, with the protocol translation logic; and

initiate, with the protocol translation logic, a corresponding remote direct memory access to the input/output server through the host channel adapter of the storage unit and the host channel adapter of the input/output server.

10. A data storage system comprising:

an input/output server including a processor, memory, and a host channel adapter;

a storage unit including a processor, memory, and a storage module;

the storage module including a storage controller, and an interface block for connecting the storage module to a corresponding memory-mapped interface;

the storage unit further including a host channel adaptor for connecting the storage unit to the input/output server, the storage unit host channel adapter being connected to a corresponding memory-mapped interface, the storage unit host channel adapter being capable of remote direct memory access to the input/output server; and

protocol translation logic configured to intercept a memory access request from the storage controller, and initiate a corresponding remote direct memory access to the input/output server through the storage unit host channel adapter and the input/output server host channel adapter;

wherein the data storage system is configured to:

establish a network connection between the host channel adapter of the input/output server and the host channel adapter of the storage unit;

receive, at the storage controller, a command;

complete the command, at the storage controller;

assert a storage controller interrupt line, at the storage controller; and

in response to the assertion of the storage controller interrupt line, delivering a message to the memory of the input/output server, with the protocol translation logic.