Abstract: Each time any one of HDDs is accessed, a corresponding relationship between the disk address of the accessed HDD and the time information indicating a time at which the HDD is accessed is added to a first operating-state management table. When a corresponding relationship with the same disk address already exists in the first operating-state management table, the time information is updated. When the first operating-state management table has no space available for new entry, corresponding relationships are deleted from the one having the oldest time information. Only HDDs of which disk address is recorded in the first operating-state management table is turned on.

Abstract: A non-volatile semiconductor memory device includes: a memory unit including a plurality of memory cells, each of the plurality of memory cells to perform a multi-level storage operation by assigning a value including a plurality of bits to at least four data states defined according to a threshold level; and a controller to control the memory unit, wherein the controller sets at least one of the plurality of bits to an error correction bit that indicates one of a first state and a second state; assigns the first state to the error correction bits that correspond to the data states having a minimum threshold level and a maximum threshold level and the second state to the error correction bits that correspond to the data state having other threshold level; and resets the error correction bit to the first state when the error correction bit indicates the second state.

Abstract: An access control device which writes data to each of predetermined storage block sets in a storage device of which a storage area has been divided into a plurality of storage blocks. The control device includes a management information storage section and an access processing section. The management information storage section stores, for each of said storage blocks, record enable/disable information indicating whether said storage block is a non-defective block in which the data can be recorded or a defective block in which the data cannot be recorded. If the data is written to each of said storage block sets, the access processing section writes the data only to non-defective blocks in said storage block set based on the record enable/disable information stored in said management information storage section.

Abstract: An asynchronous interface circuit for transferring a data stream between different clock domains, the asynchronous interface circuits includes a data holding circuit for sequentially receiving and transferring data of the data stream in synchronism with a first clock signal, and holding the received data until an input of a next data, an asynchronous memory for sequentially receiving the data held in the data holding circuit in synchronism with the first clock signal and for outputting the data in the order of inputting in synchronism with a second clock signal. The asynchronous interface circuit further includes a monitor for detecting an operating state of the asynchronous memory, and a selector for selecting one of the data output from the asynchronous memory and the data output from the data holding circuit on the basis of a detecting result of the monitor.

Abstract: A crypt processor is connected to a host computer and a storage apparatus. Data from the host computer is transferred to the crypt processor via DMA (Direct Memory Access) to be encrypted and then stored in the storage apparatus. The crypto processor acquires a descriptor defining a DMA number for identifying a DMA channel used to DMA-transfer the data. The crypto processor stores therein, based on the DMA number included in the acquired descriptor, the data transferred using the same DMA channel in units of a data size specified in a data bus. The crypto processor then encrypts the stored data in units of data size specified in a crypt system, and transfers the encrypted data to the storage apparatus.

Abstract: Each of (n?1) 2-bit checking units, where n is an integer larger than or equal to 4, receives n-bit redundant encoded data generated from 1-bit input data, and outputs 2-bit check data based on a result of comparison between bits of the encoded data, combinations of the bits differing in each comparison. An all-bit checking unit outputs all-bit check data based on exclusive ORs of all-bit of the encoded data. An error detecting unit detects errors in the encoded data on the basis of the (n?1) sets of 2-bit check data and the all-bit check data, and outputs the input data on the basis of the result of error detection.

Abstract: A control apparatus includes a capacitor to store electric power supplied from the power supply unit and to supply the stored electric power to the control apparatus when the power supply from the power supply unit is stopped, a first nonvolatile memory, a second nonvolatile memory, a first controller, and a second controller. The first controller writes the data, stored in the cache memory, into the first nonvolatile memory when the external power supply is stopped verifies whether the data stored in the first nonvolatile memory is normal, and sends information of area where the data in the first nonvolatile memory is not normal when the verification indicates that the writing is not normal. And the second controller writes the information sent from the first controller into the second nonvolatile memory.

Abstract: An access control apparatus for controlling an access to a storage device, the access control apparatus includes a measuring unit configured to measure the time to erase data stored in the storage device, and a determination unit configured to determine a data size of an error correcting code added to data stored in the storage device in accordance with the time measured by the measuring unit. The access control apparatus includes a generation unit configured to generate the error correcting code having the data size determined by the determination unit, and an access controller configured to write the data and the error correcting code generated by the generation unit into the storage device.

Abstract: In a method of controlling an information processing system in which an information processing device is connected to each of a plurality of input/output ports provided in a routing device and having a first property or a second property, for conducting data transmission among the information processing devices via the routing device, a step of causing all of the information processing devices to halt data transmission, a step of resetting properties and identification information of the input/output ports with the second properties other than the input/output port with the first property which cannot be used, in the routing device, and a step of causing the information processing devices to restart the data transmission after the reset of the identification information are executed.

Abstract: A storage system including a storage, has a first power supplier for supplying electronic power, a second power supplier for supplying electronic power when the first power supplier not supplying electronic power to the storage system, a cache memory for storing data sent out from a host, a non-volatile memory for storing data stored in the cache memory, and a controller for writing the data stored in the cache memory into the non-volatile memory when the second supplier supplying electronic power to the storage system, for stopping the writing and for deleting data stored in the non-volatile memory so until a free space volume of the non-volatile memory being not less than a volume of the data stored in the cache memory when the first supplier restoring electronic power to the storage system.

Abstract: A storage device includes a programmable device into which predetermined control data is written, a control data storing unit that stores therein write control data and read control data, the write control data being control data for realizing a function to save data stored in a cache memory into a nonvolatile memory when an abnormal shut-down occurs and the read control data being control data for realizing a function to restore the data saved in the nonvolatile memory into the cache memory when an electric power source is turned on after the abnormal shut-down, a writing unit that, when an electric power source is turned on after occurrence of the abnormal shut-down of the storage device, writes the read control data into the programmable device, and a restoring instructing unit that instructs the programmable device to restore the data saved in the nonvolatile memory into the cache memory.

Abstract: In response to a request from a central processing unit (CPU) 11 (i.e., firmware) of a node 10, a transfer control unit 14a of a direct memory access (DMA) controller 14 transmits a message and data to another discretionary node 3 by way of a serial bus 1, a switch 2 or the like. In this event, the firmware stores data to be transmitted, a message, and a descriptor thereof in memory 12. In the case of requesting the transmission of the message, the descriptor contains a flag indicating “whether or not there is a need to wait for a response from the data transmission destination”. If the flag is set to ON, the transfer control unit 14a notifies the firmware of a simulated completion immediately instead of waiting for a completion response from the transmission destination node 3.

Abstract: An asynchronous interface circuit for transferring a data stream between different clock domains, the asynchronous interface circuits includes a data holding circuit for sequentially receiving and transferring data of the data stream in synchronism with a first clock signal, and holding the received data until an input of a next data, an asynchronous memory for sequentially receiving the data held in the data holding circuit in synchronism with the first clock signal and for outputting the data in the order of inputting in synchronism with a second clock signal. The asynchronous interface circuit further includes a monitor for detecting an operating state of the asynchronous memory, and a selector for selecting one of the data output from the asynchronous memory and the data output from the data holding circuit on the basis of a detecting result of the monitor.

Abstract: A storage apparatus includes a backup processing unit that stores data stored in a first memory into a second memory as backup data upon occurrence of a power failure, a restore processing unit that upon recovery from the power failure restores the backup data backed up in the second memory to the first memory and erases the backup data, and an erasure processing termination unit that terminates the erasure processing upon a power failure occurring during erasure processing for erasing the backup data stored in the second memory, and a re-backup processing unit that re-backs up data in the first memory corresponding to the backup data erased from the second memory before the erasure processing is terminated by the erasure processing termination unit to a location in the second memory subsequent to a last location that contains the backup data which has not been erased.

Abstract: An information processing apparatus includes, a first storage unit, a second storage unit in which data stored in the first storage unit is backed up, and a memory controller that controls data backup operation. The memory controller divides a transfer source storage area into portions, and provides two transfer destination areas, each of the two transfer destination areas being divided into portions, backs up data in a direction from a beginning address of each divided area of the transfer source storage area to an end address thereof in one of the transfer destination areas provided for each divided area of the transfer source storage area, and backs up data in a direction from the end address of each divided area of the transfer source storage area to the beginning address thereof in the other transfer destination storage area.

Abstract: An access control device which writes data to each of predetermined storage block sets in a storage device of which a storage area has been divided into a plurality of storage blocks. The control device includes a management information storage section and an access processing section. The management information storage section stores, for each of said storage blocks, record enable/disable information indicating whether said storage block is a non-defective block in which the data can be recorded or a defective block in which the data cannot be recorded. If the data is written to each of said storage block sets, the access processing section writes the data only to non-defective blocks in said storage block set based on the record enable/disable information stored in said management information storage section.

Abstract: A DMA circuit operates a plurality of DMA channels in parallel, enabling reduction of the circuit scale and fewer development processes. A channel manager circuit reads in sequence the control information for each DMA channel from control memory, performs analysis, and according to the divided DMA control sequence, performs state processing (DMA control). Further, the channel manager circuit updates the control information, writes back the control information to the control memory, and executes time-division control of the plurality of DMA channels. Hence the circuit scale can be reduced, contributing to decreased costs, and the number of development processes can be reduced.

Abstract: To be able to transmit a response packet to the original request node after a bus ID/a device ID is replaced in the PCI-Express switch for a PCI-Express communication system, a unique node ID for indicating each node is set to the nodes. Additionally, it is confirmed whether or not the packet is transferred in the correct order in a series of packet transfers. For that purpose, a sequence code indicating the sequence number of a packet in a series of packet transfer is set in an address field of a packet of data transfer.

Abstract: A DMA apparatus which reads data corresponding to a descriptor from memory, and a dividing unit in a descriptor management device divides one descriptor into a plurality of sub-descriptors. A plurality of DMA controllers produce a plurality of reading requests for reading data corresponding to the plurality of sub-descriptors from the memory. A memory controller reads the corresponding data from the memory according to the plurality of reading requests.

Abstract: In a DMA control method in which a DMA controller transfers data in memory to an input/output device in accordance with the control information which is provided by a processing device to a DMA controller, a processing device implements a step in which the processing device sets an information block comprising the control information and the data in the memory; a step in which address information of the information block is provided by the processing device to the DMA controller; a step in which the DMA controller reads the information block from the memory based on the address information and extracts the control information; and a step in which the DMA controller transfers the data in the information block to the I/O device based on the control information.