Switch module and storage system
According to one embodiment, a switch module includes a first port with PCIe/NVMe standard being connectable to a host, second ports with PCIe/NVMe standard being connectable to storage devices respectively, and a controller to make the host recognize the storage devices as a virtual storage device.
1. A switch module comprising:
a first port being connectable to a host in accordance with Peripheral Component Interconnect Express/Non-Volatile Memory Express (PCIe/NVMe) standard;
second ports being connectable to storage devices in accordance with the PCIe/NVMe standard respectively; and
a controller configured to make the host recognize the storage devices as a single virtual storage device by
allocating a physical function of each of the storage devices to one of virtual functions of the single virtual storage device,
allocating a virtual function of each of the storage devices to one of the virtual functions of the single virtual storage device, and
showing, to the host,
a physical function of the single virtual storage device, and
the virtual functions of the single virtual storage device.
2. The switch module of claim 1 , further comprising
a memory storing a mapping table which associates the physical and virtual functions of the storage devices with the virtual functions of the virtual storage device.
3. The switch module of claim 1 , wherein
the controller defines the physical function and the virtual functions of the virtual storage device and the physical and virtual functions of the storage devices based on Single root I/O virtualization (SRIOV) standard or Multi-root I/O virtualization (MRIOV) standard.
4. The switch module of claim 1 , further comprising
a memory buffering a data transfer between the host and the storage devices.
5. The switch module of claim 1 , wherein
the storage devices are accessible to a memory in the host.
6. The switch module of claim 1 , further comprising
a CPU managing electric powers of the storage devices.
7. The switch module of claim 1 , wherein
the controller indicates an initialization to the storage devices in series after receiving a request of the initialization of the virtual storage device from the host, and transfers a completion response to the host after completing the initialization of all of the storage devices.
8. The switch module of claim 1 , wherein
the controller selects one storage device as a target of a request from the storage devices after receiving the request from the host to the virtual storage device, and transfers a completion response to the host after completing the request in the one storage device as the target of the request.
9. The switch module of claim 1 , wherein
the controller indicates a request to the host after receiving the request from one of the storage devices to the host, and transfers a completion response to one of the storage device after completing the request in the host.
10. The switch module of claim 1 , wherein
the storage devices are solid state drives (SSDs).
11. A storage system comprising:
a host;
storage devices; and
a switch module connected between the host and the storage devices,
the switch module comprises:
a first port being connectable to the host in accordance with Peripheral Component Interconnect Express/Non-Volatile Memory Express (PCIe/NVMe) standard;
second ports being connectable to the storage devices in accordance with the PCIe/NVMe standard respectively; and
a controller configured to make the host recognize the storage devices as a single virtual storage device by
allocating a physical function of each of the storage devices to one of virtual functions of the single virtual storage device,
allocating a virtual function of each of the storage devices to one of the virtual functions of the single virtual storage device, and
showing, to the host,
a physical function of the single virtual storage device, and
the virtual functions of the single virtual storage device.
12. The storage system of claim 11 , wherein
the switch module further comprises a memory storing a mapping table which associates the physical and virtual functions of the storage devices with the virtual functions of the virtual storage device.
13. The storage system of claim 11 , wherein
the controller defines the physical function and the virtual functions of the virtual storage device and the physical and virtual functions of the storage devices based on Single root I/O virtualization (SRIOV) standard or Multi-root I/O virtualization (MRIOV) standard.
14. The storage system of claim 11 , wherein
the switch module further comprises a memory buffering a data transfer between the host and the storage devices.
15. The storage system of claim 11 , wherein
the host comprises a memory to which the storage devices are accessible.
16. The storage system of claim 11 , wherein
the switch module further comprises a CPU managing electric powers of the storage devices.