Hitachi Global Storage Technologies Netherlands B.v.

International Business Machines Corporation

Hgst Netherlands, B.v.

Hitachi Global Storage Technologies

Hget Netherlands B.v.

Jorge Campello De Souza

Richard M H New

Donald Joseph Molaro

Bruce Alexander Wilson

Damien C D Le Moal

Cyril Guyot

Zvonimir Z Bandic

Marco Sanvido

Anand Kulkarni

Chunqi Han

Dharmendra S Modha

Thomas R Albrecht

Jeffrey Alan Kusnitz

Mario Blaum

Jihoon Park

Sridhar Rajagopalan

Mason Lamar Williams

Prakash Kasiraj

Atsushi Kanamaru

Ivana Djurdjevic

Frank R Chu

Yuval Cassuto

Brian Harry Marcus

Thiruvilwamalai Venkatraman Raman

Tadahisa Kawa

Tomohiro Harayama

Frank Rui-Feng Chu

Brian H Marcus

A system for enhancing command scheduling is provided. In particular embodiments, the system includes a processor and a scheduler that receives commands from the processor for accessing a storage device. The scheduler receives a set of commands, some of which have a deadline, and the scheduler is configured to determine an execution order for those commands. The scheduler is also configured to defer the execution of one or more of those commands to a later time.

Adaptive command scheduling

A method is described for allowing disk drives, such as shingle-written magnetic recording (SMR) drives, to be shipped for customer use with portions of the magnetic media being left untested. The testing is then completed by the drive self-testing in the field. The drive is made functional at the factory by fully testing at least one operational set of regions including an I-region, an E-region and a write cache region. The operational set of regions works as a separate self-contained virtual disk drive and can be used immediately. The remaining untested areas on the media can be tested in the field by a background task and/or when the first write command is received that requires a new track or operational set of regions (on-the fly testing).

Distributed field self-test for shingled magnetic recording drives

A data storage device accepts queued read and write commands that have deadlines. The queued read and write commands are requests to access the data storage device. The deadlines of the queued read and write commands can be advisory deadlines or mandatory deadlines.

Data storage devices accepting queued commands having deadlines

A system includes a storage device and a scheduler. The scheduler determines if deadlines of requests for accessing the storage device fall within first and second sliding windows. The scheduler issues requests that are in the first sliding window in a first order of execution and requests that are in the second sliding window in a second order of execution.

Techniques for scheduling requests for accessing storage devices using sliding windows

Watermarks for patterned magnetic media. The watermarks are used to demonstrate the unauthorized replication of a patterned magnetic media. The watermarks include a dibit, a pattern in an open region, shifting of data, shifting of a sync mark and large length scale perturbations. Also described are methods to determine if a watermark appears on a patterned media.

Encryption methods for patterned media watermarking

A data storage device encrypts data stored in non-volatile memory using a bulk encryption key. The data storage device uses a key derivation function to generate an initial encryption key. The data storage device then wraps an intermediate encryption key with the initial encryption key and stores the wrapped intermediate key in the non-volatile memory. The data storage device wraps the bulk encryption key with the intermediate encryption key and stores the wrapped bulk encryption key in the non-volatile memory. The data storage device can unwrap the wrapped intermediate key to generate the intermediate encryption key using the initial encryption key. The data storage device can unwrap the wrapped bulk encryption key to generate the bulk encryption key using the intermediate encryption key. The data storage device decrypts data stored in the non-volatile memory using the bulk encryption key.

Techniques for encrypting data on storage devices using an intermediate key

Techniques for securing data stored on a data storage device are provided. The data storage device encrypts the data using a bulk encryption key and stores the bulk encryption key in non-volatile memory in an encrypted format. The data storage device generates a challenge and response pair, wraps a secret key with the response to generate a wrapped secret key, and stores the challenge and the wrapped secret key in the non-volatile memory. The data storage device authenticates a host by reading the challenge and the wrapped secret key from the non-volatile memory, erasing the challenge and the wrapped secret key from the non-volatile memory, sending the challenge to the host, receiving the response from the host, and unwrapping the wrapped secret key using the response from the host to regenerate the secret key.

Challenge and response access control providing data security in data storage devices

Flash memory devices and associated methods are described for controlling data errors in the devices through various forms of decoding, error correction, and wear concentration. To this end, a flash memory device may be partitioned into a plurality of sectors. Data may then be received from, for example, a host processor for storage within the flash memory device. Storage durations of the data are then estimated and the data is stored in the data sectors based on those estimated storage durations.

Error control in a flash memory device

Patterned-media magnetic recording disks are made from a master template that has nondata regions that contain a pattern of one or more discrete nondata islands and discrete gaps, with the pattern representing a scrambled number. All disks made from the master template, or from replica molds made from the master, will have the same patterns. When the disks are DC-magnetized so that all the nondata islands are magnetized in the same direction, these patterns will include one or more of discrete magnetized nondata islands and discrete nonmagnetic gaps that are scrambled in a pseudo-random manner. During operation of the disk drive the patterns are detected by the read head and interpreted within the disk drive using knowledge of the pseudo-random scrambling function, so that reading and writing of data can occur in the conventional manner. If the disks are copied in an attempt to replicate the master template, the resulting disks will be inoperable in a disk drive because of the scrambling.

Patterned-media magnetic recording disk with cryptographically scrambled patterns and disk drive operable with the disk

Techniques for optimizing hard disk drive performance. According to one embodiment, a storage system includes a storage unit that stores data and a controller. The controller receives an idle mode indication and performs at least one operation based on the idle mode indication. According to another embodiment, a host system includes a processor and a scheduler that is operative to issues commands. The processor computes the idle mode indication, and the processor sends the idle mode indication to the storage system.

Using idle mode prediction to improve storage system performance

The invention is a storage device which implements a write barrier command and provides means for a host to designate other write commands as being sensitive or insensitive to the existence of write barrier commands. The device can optimize the execution of commands by changing the order of execution of write commands that are insensitive to write barrier command. In an embodiment of the invention a flag associated with the write command indicates whether the command is sensitive or insensitive to the existence of write barrier commands. In an embodiment of the invention the write barrier command can be implemented as a write command with a flag that indicates whether the command is a write barrier command. In one embodiment of the invention the queue of commands and data to be written to the media is stored in a non-volatile cache.

Storage device with write barrier sensitive write commands and write barrier insensitive commands

A verifiable security mode is provided for securing data on a storage device, such as a hard disk drive. When the verifiable security mode is enabled, only authenticated accesses to data stored on the storage device are permitted after entering a password. An end user is prevented from disabling the verifiable security mode. The verifiable security mode can be set to allow or disallow an administrator from disabling the verifiable security mode. The verifiable security mode can be implemented, for example, in firmware on a hard disk drive (HDD).

Techniques for providing verifiable security in storage devices

Enhancements to the functionality of a file system are provided. A file system can provide an additional level of error correction, in addition to the error correction provided by a data storage device. An extension to the metadata area in a file system can store index information about data files that the file system can use to reduce the time it takes to access the files. A file system can use extended metadata to store conditional access information for data files stored in the file system. A data storage device can also examine and characterize the data being stored in order to categorize a user's files automatically. Modules can be loaded into a file system to provide new functionality to the file system. The modules can load additional modules to extend their functionality.

Techniques for enhancing the functionality of file systems

A system for enhancing the reliability of file systems is provided. In particular embodiments, the system includes a data storage device that includes one or more journal blocks, one or more primary metadata blocks, and one or more mirror metadata blocks. The system also includes a file system that writes metadata to the one or more journal blocks before writing the metadata to both the one or more primary metadata blocks and to the one or more mirror metadata blocks.

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Cupertino, CA, United States of America

Jorge Campello De Souza