DRAM-less SSD with command draining
A data storage device includes one or more memory device and a controller that is DRAM-less coupled to the one or more memory devices. The controller is configured to receive a command from a host device, begin execution of the command, and receive an abort request command for the command. The command includes pointers that direct the data storage device to various locations on the data storage device where relevant content is located. Once the abort command is received, the content of the host pointers stored in the data storage device RAM are changed to point to the HMB. The data storage device then waits until any already started transactions over the interface bus that are associated with the command have been completed. Thereafter, a failure completion command is posted to the host device.
1. A data storage device, comprising:
one or more memory means; and
a controller coupled to the one or more memory means, wherein the data storage device is DRAM-less, and wherein the controller is configured to:
receive an abort command request from a host device;
allocate a first host memory buffer (HMB) and a second HMB for holding a series of data associated with the abort command request, wherein:
the first HMB is configured to drain the series of data associated with the abort command request; and
the second HMB is configured to point to a drain buffer; and
return a completion message to the host device.
2. The data storage device of claim 1 , wherein the first HMB is the drain buffer.
3. The data storage device of claim 1 , wherein data associated with the abort command are drained to the drain buffer in read and write operations.
4. The data storage device of claim 1 , wherein the second HMB is configured to contain a buffer pointer list.
5. The data storage device of claim 4 , wherein all but a last pointer in the buffer pointer list points to the drain buffer.
6. The data storage device of claim 5 , wherein the last pointer in the buffer pointer list points to a different pointer in the buffer pointer list.
7. The data storage device of claim 1 , wherein a failure completion message is delivered while data transfer associated with the original command is still processing, wherein the data transfer occurring after a failure completion message is delivered utilize modified one or more pointers.
8. The data storage device of claim 1 , wherein the controller is further configured to drain a set of data, wherein the draining the set of data comprises pointing each pointer to a drain buffer.
9. The data storage device of claim 8 , wherein a last pointer points to a same buffer list in which the last pointer resides.
10. The data storage device of claim 1 , wherein the controller is further configured to:
receive an original command from the host device;
determine to complete the original command with Advanced Command Retry (ACR);
allocate one or more buffers for holding a set of data associated with the original command;
return a completion message with an ACR indication to the host device, wherein the completion message requests the host device to re-try the original command;
execute the original command while transferring data to the allocated one or more buffers;
receive a reissued original command from the host device; and
copy data for the reissued original command from the allocated one or more buffers.