Abstract: A method and system for intelligent bit recovery identifies toggling bits, which change in value from one read to the next, and examines a subset of potential bit patterns. The subset is a fraction of the potential bit patterns, and is based on an understanding of the flash memory and the problems that may cause the toggling bits. The intelligent bit recovery may analyze at least one aspect of the flash memory to identify a problem, or plurality of problems, that is potentially causing the toggling bits, and to select the subset of potential bit patterns as potential solutions. The subset of potential bit patterns examined by the intelligent bit recovery is a small fraction of the entire set of potential bit patterns.

Abstract: A method and system intelligent bit recovery is provided. The intelligent bit recovery determines which bits are toggling, and examines a subset of the potential bit patterns to determine which in the subset of potential bit patterns is valid. The subset is a fraction of the potential bit patterns, and is based on an understanding of the flash memory and the problems that may cause the toggling bits. The intelligent bit recovery may analyze at least one aspect of the flash memory to identify which problem is potentially causing the toggling bits, and to select the subset of potential bit patterns as solutions for the determined problem. Or, the intelligent bit recovery selects potential bit patterns for multiple potential problems. In either way, the subset of potential bit patterns examined by the intelligent bit recovery is a small fraction of the entire set of potential bit patterns.

Abstract: 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.

Abstract: A data storage device comprises virtual storage devices that are each assigned to a subset of data sectors in a non-volatile memory of the data storage device. The data storage device receives configuration metadata for configuring each of the virtual storage devices from a host operating system. The configuration metadata is received in a standard format that is file system independent. The configuration metadata comprises a range of logical block addresses and a virtual storage device number assigned to each of the virtual storage devices. Each of the virtual storage device numbers is a unique identifier used by the data storage device to differentiate between the virtual storage devices. The data storage device uses the virtual storage device numbers and logical block addresses to identify data sectors in the virtual storage devices that are accessible by virtual machine operating systems.

Abstract: A hard disk drive is provided for enhancing random number generation. In particular embodiments, the hard disk drive includes a storage subsystem and a controller. The controller generates a random number based on information associated with the storage subsystem. The controller transmits the random number to a host system.

Abstract: 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.

Abstract: 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).

Abstract: A data storage apparatus includes a data storage medium, a write element, a non-volatile cache memory circuit, and a controller circuit. The controller circuit is configured to record data on the data storage medium in groups of overlapping tracks using the write element. The controller circuit is configured to store a shingle block of data from a subset of the overlapping tracks in the non-volatile cache memory circuit, while at least a portion of the data in the shingle block of data is updated.

Abstract: Some embodiments include a storage device with a storage medium having a memory capacity. The storage device also includes virtual storage device firmware that is configured to directly respond to commands from a guest operating system in a virtual machine for accesses to a subset of the memory capacity of the storage medium when a virtual storage device is enabled.

Abstract: A data storage apparatus includes a data storage medium, a write element, a non-volatile cache memory circuit, and a controller circuit. The controller circuit is configured to record data on the data storage medium in groups of overlapping tracks using the write element. The controller circuit is configured to store a shingle block of data from a subset of the overlapping tracks in the non-volatile cache memory circuit, while at least a portion of the data in the shingle block of data is updated.

Abstract: A storage system that stores verify commands for all the write commands requiring verification in a verify-list that will be processed as a background task is described. The verify-list can include coded data fields that flexibly designate selected alternative states or possibilities for how and where the user data is actually stored. Alternatives for the verify-list include storing the actual raw data, no data, the data in compressed form, a CRC type signature of the data and/or a pointer to a backup copy of the data that is stored either in non-volatile memory such as flash memory or on the disk media in a temporary area. In case of a verification error in various alternative embodiments the user data can be recovered using the backup copy in the verify-list in the write cache, the backup copy in flash memory or on the disk, or from the host.

Abstract: A hard disk drive is provided for enhancing random number generation. In particular embodiments, the hard disk drive includes a storage subsystem and a controller. The controller generates a random number based on information associated with the storage subsystem. The controller transmits the random number to a host system.

Abstract: A disk drive that includes nonvolatile memory for use when the disk drive is in standby mode also uses the nonvolatile memory, together with a volatile memory, as a cache when the disk drive is in both standby and non-standby mode. Each of the data blocks stored on the disks is also stored in a cache line of either the volatile memory or the nonvolatile memory. Each cache line in both the volatile and nonvolatile memory stores one or more data blocks and an associated tag. The tag contains at least a portion of the logical block address that corresponds to the data block that is stored in the cache line. The volatile memory also has locations allocated to store tags that “shadow” the tags in the nonvolatile memory. By searching the shadow tags in the faster volatile memory, it can be determined if a data block is in the nonvolatile memory without searching the slower nonvolatile memory.

Abstract: A storage system that stores verify commands for all the write commands requiring verification in a verify-list that will be processed as a background task is described. The verify-list can include coded data fields that flexibly designate selected alternative states or possibilities for how and where the user data is actually stored. Alternatives for the verify-list include storing the actual raw data, no data, the data in compressed form, a CRC type signature of the data and/or a pointer to a backup copy of the data that is stored either in non-volatile memory such as flash memory or on the disk media in a temporary area. In case of a verification error in various alternative embodiments the user data can be recovered using the backup copy in the verify-list in the write cache, the backup copy in flash memory or on the disk, or from the host.

Abstract: Methods and apparatus of the present invention include multiple flash storage devices that are configured to form a single storage device that is flexible and scalable. Reliability and performance are improved while keeping the power consumption benefits compared to conventional hard disk drives.

Abstract: A hard disk drive enhances random number generation. In particular embodiments, the hard disk drive includes a controller, a hard disk, and a head. The head includes a read sensor for reading patterns on the hard disk. The controller generates a random number based on information associated with the position of the head relative to at least one track of the hard disk.

Abstract: A data storage device comprises virtual storage devices that are each assigned to a subset of data sectors in a non-volatile memory of the data storage device. The data storage device receives configuration metadata for configuring each of the virtual storage devices from a host operating system. The configuration metadata is received in a standard format that is file system independent. The configuration metadata comprises a range of logical block addresses and a virtual storage device number assigned to each of the virtual storage devices. Each of the virtual storage device numbers is a unique identifier used by the data storage device to differentiate between the virtual storage devices. The data storage device uses the virtual storage device numbers and logical block addresses to identify data sectors in the virtual storage devices that are accessible by virtual machine operating systems.

Abstract: 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.

Abstract: Some embodiments include a storage device with a storage medium having a memory capacity. The storage device also includes virtual storage device firmware that is configured to directly respond to commands from a guest operating system in a virtual machine for accesses to a subset of the memory capacity of the storage medium when a virtual storage device is enabled.

Abstract: 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.