Patent ID: 7447811
Filing Date: 2008-11-04
Classification: G06F

Abstract:
1. A storage device provided with a storage control unit which performs storage control, being connected to a host for operation, and has a host interface control unit for performing interface control with the host, a storage control firmware having a storage control program and electrically rewritable non-volatile memory, wherein necessary information is stored during exchanging an activation program for the storage control firmware using the non-volatile memory, and the activation program is exchanged using the information without disconnection to the host or without an erroneous response to a command from the host, the storage device comprising: (a) a first unit for stopping a process of a command received from the host upon or after an issue of an instruction from an external unit when exchange of an activation program of storage control firmware is started, separately storing information about a command received from the host and an event in the non-volatile memory to hold an ordinal relation between the command and the event, retrieving a command corresponding to a cancellation when the host instructs the cancellation of an issued command, and placing the command in an invalid status; (b) a second unit for suppressing an interrupt from the host interface control unit to the storage control firmware when stop of processing the command is completed, continuously transferring the command received from the host to the non-volatile memory, updating an input pointer of a command queue in the non-volatile memory, and controlling not to perform processing of the storage control firmware; (c) a third unit for making the storage control firmware valid by activating new storage control firmware having a new program after exchanging the activation program of the storage control firmware, and performing control to hold contents of the non- volatile memory; (d) a fourth unit for holding a logical connection status with the host without disconnection not to initialize the host interface control unit when activation is performed by the new storage control firmware, thereby performing control of continuing an operation with a status before the activation maintained without resetting the host interface control unit; and (e) a fifth unit for restoring a host connection to restore a logical connection status before starting a host command processing after the activation because the storage control firmware forgets the logical connection status with the host by the activation of the new storage control firmware.