Command draining using host memory buffer
The present disclosure generally relates to aborting a command efficiently using the host memory buffer (HMB). The command contains 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 devices; and
a controller coupled to the one or more memory devices, wherein the controller is configured to:
post a failed completion message associated with a first command to a host device;
receive a second command from the host device, wherein the second command is a re-issue of the first command;
retrieve data associated with the first command from a host memory buffer (HMB) of the host device, wherein the HMB comprises a first buffer and a second buffer, wherein the first buffer is a drain buffer and the second buffer is a list of buffer pointers;
modify content of the buffer pointers to point to the first buffer before posting the failed completion message; and
execute the second command using the retrieved data associated with the first command.
2. The data storage device of claim 1 , wherein the failed completion message requests the host device to re-try the first command.
3. The data storage device of claim 1 , wherein the first command includes an Advanced Command Retry (ACR) request.
4. The data storage device of claim 3 , wherein the controller is further configured to allocate one or more buffers in the HMB for the command responsive to receiving the first command having the ACR request.
5. The data storage device of claim 4 , wherein the controller is further configured to store the data associated with the first command in the allocated one or more buffers in the HMB responsive to posting the failed completion message to the host device.
6. The data storage device of claim 5 , wherein the controller is further configured to update one or more pointers to point to the allocated one or more buffers in the HMB responsive to the storing.
7. The data storage device of claim 1 , wherein the host device does not send data associated with the second command with the second command.
8. The data storage device of claim 1 , wherein the controller is further configured to queue the data associated with the first command stored in the HMB to be retrieved.
9. The data storage device of claim 1 , wherein posting the failed completion message is in response to aborting the command.