Storage system capable of invalidating data stored in a storage device thereof

Patent metadata

Field	Value
Publication number	US-2016299715-A1
Application number	US-201615015052-A
Country	US
Kind code	A1
Filing date	Feb 3, 2016
Priority date	Apr 10, 2015
Publication date	Oct 13, 2016
Grant date	—

Abstract

A storage device includes a non-volatile semiconductor storage device including a plurality of physical blocks, and a controller. The controller is configured to maintain a mapping of logical addresses to locations within the physical blocks, send, to a host, a first list that contains logical addresses corresponding to one or more target physical block that are targeted for garbage collection, and then receive, from the host, a second list that contains one or more logical addresses in the first list, and invalidate data stored in the logical addresses in the second list prior to the garbage collection.

First claim

What is claimed is:

1 . A storage device, comprising:
a non-volatile semiconductor storage device including a plurality of physical blocks; and a controller configured to maintain a mapping of logical addresses to locations within the physical blocks, send, to a host, a first list that contains logical addresses corresponding to one or more target physical blocks that are targeted for garbage collection, and then receive from the host, a second list that contains one or more logical addresses in the first list, and invalidate data stored in the logical addresses in the second list prior to the garbage collection.

2 . The storage device according to claim 1 , wherein
the data stored in the logical addresses in the first list includes both valid and invalid data.

3 . The storage device according to claim 1 , wherein
the data stored in the logical addresses in the first list includes only valid data.

4 . The storage device according to claim 1 , wherein
the logical addresses in the first list are mapped to locations within physical blocks that are selected based on age of valid data contained in the physical blocks.

5 . The storage device according to claim 1 , wherein
the logical addresses in the first list are mapped to locations within physical blocks that are selected based on a ratio of invalid data to valid data contained in the physical blocks.

6 . The storage device according to claim 1 , wherein
the controller sends the first list, in response to a command from a host that requests the first list.

7 . The storage device according to claim 1 , wherein
the first list is sent when capacity of free space in the physical blocks is smaller than a predetermined threshold.

8 . A computing device comprising a processing unit programmed to carry out a method of communicating with a storage device including a plurality of physical blocks, said method comprising:
receiving from the storage device, a first list that contains logical addresses corresponding to one or more target physical blocks that are targeted for garbage collection; generating a second list that contains one or more logical addresses in the first list; and transmitting the second list to the storage device, so as to cause the storage device to invalidate data stored in the logical addresses in the second list prior to the garbage collection.

9 . The computing device according to claim 8 , wherein
the data stored in the logical addresses in the second list includes only valid data.

10 . The computing device according to claim 8 , wherein the method further comprises:
issuing a first command to the storage device; receiving from the storage device in response to the first command, capacity of free space in the plurality of physical blocks; determining that the capacity is smaller than a predetermined threshold; and issuing a second command requesting the first list to the storage device, upon determining that the capacity is smaller than the predetermined threshold.

11 . The computing device according to claim 8 , wherein
the one or more logical addresses contained in the second list correspond to data that are determined to be unnecessary.

12 . The computing device according to claim 11 , wherein
the data are determined to be unnecessary, based on a cache hit ratio with respect to the data or a frequency of access to the data.

13 . The computing device according to claim 8 , wherein
a file system of the computing device causes the processing unit to generate the second list, and a driver of the computing device causes the processing unit to send the generated second list to the storage device.

14 . The computing device according to claim 8 , wherein the method further comprises:
updating index data stored in the computing device, so as to reflect the invalidation of the data stored in the logical addresses in the second list.

15 . A storage device, comprising:
a non-volatile semiconductor storage device including a plurality of physical blocks; and a controller configured to maintain a mapping of logical addresses to locations within the physical blocks, receive from a host a write command, and in response thereto, store first information indicating expiration time of data associated with the write command, wherein when the expiration time passes, the controller is configured to determine the data as no longer valid.

16 . The storage device according to claim 15 , wherein
the controller is further configured to carry out garbage collection by copying the data for which the expiration time has not yet passed and without copying the data for which the expiration time has passed.

17 . The storage device according to claim 15 , wherein
the expiration time is set as a predetermined period time from when the data is stored.

18 . The storage device according to claim 15 , wherein
the expiration time is set according to a lifetime of the data designated by the host.

19 . The storage device according to claim 18 , wherein
the lifetime of the data is designated in the write command.

20 . The storage device according to claim 18 , wherein
the controller is further configured to receive a command to associate a physical block with stream identification information, before receiving the write command, and
the lifetime of the data is designated in the command.

Assignees

• Toshiba Kk

Inventors

• Hashimoto Daisuke
• Kanno Shinichi

Classifications

• G06F3/0619 Primary

  in relation to data integrity, e.g. data losses, bit errors · CPC title

• G06F3/0655

  Vertical data movement, i.e. input-output transfer; data movement between one or more hosts and one or more storage devices · CPC title

• G06F2212/7205

  Cleaning, compaction, garbage collection, erase control · CPC title

• G06F12/0253

  Garbage collection, i.e. reclamation of unreferenced memory · CPC title

• G06F2212/7201

  Logical to physical mapping or translation of blocks or pages · CPC title