Storage system managing metadata, host system controlling storage system, and storage system operating method

Patent metadata

Field	Value
Publication number	US-11726688-B2
Application number	US-202016834779-A
Country	US
Kind code	B2
Filing date	Mar 30, 2020
Priority date	Oct 2, 2019
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

A storage system communicates with a host system and includes a storage device including storage medium divided into a plurality of blocks including high reliability blocks and reserve blocks, and a controller. The controller provides the host system with block information identifying the high reliability blocks among the plurality of blocks, receives a block allocation request from the host system, wherein the block allocation request is defined with reference to the block information and identifies at least one high reliability block to be used to store metadata, and allocates at least one high reliability block to a meta region in response to the block allocation request. The controller includes a bad block manager that manages an allocation operation performed in response to the block allocation request, and a repair module that repairs an error in metadata stored in one of the high reliability blocks.

First claim

What is claimed is:

1. A storage system including an Open-Channel Solid-State Drive (OC-SSD) and communicating with a host system, the host system external from the storage system, the storage system comprising:
a storage device including storage medium divided into a plurality of blocks including high reliability blocks and reserve blocks; and
a controller configured to:
send, to the host system, block information identifying the high reliability blocks among the plurality of blocks and information indicating a plurality of repair operation techniques supported by the storage system,
receive a block allocation request from the host system, wherein the block allocation request identifies at least one of the high reliability blocks to be allocated to a meta region where metadata is stored and includes information identifying a data mirroring technique or a repair parity technique as a selected repair operation technique, from among the plurality of repair operation techniques, selected by the host system,
allocate the at least one of the high reliability blocks to the meta region in response to the block allocation request,
set the selected repair operation technique, selected by the host system, as a set repair operation technique for the high reliability blocks, and
select a different number of the reserve blocks to be allocated to the meta region based on the set repair operation technique, wherein:

the controller comprises a bad block manager configured to manage a block allocation operation performed in response to the block allocation request, and a repair module configured to repair an error in the metadata stored in the at least one of the high reliability blocks, and
when sudden power-off (SPO) occurs, the controller selectively accesses blocks included in the meta region and provides the metadata to the host system.

2. The storage system of claim 1 , wherein:
when one of at least one of the reserve blocks becomes exhausted, the controller is further configured to send information identifying the one of the at least one of the reserve blocks becoming exhausted to the host system, and
in response to a request from the host system requesting allocation of an additional reserve block from among the reserve blocks, the controller is further configured to additionally allocate the additional reserve block to the meta region.

3. The storage system of claim 1 , wherein the data mirroring technique writes the metadata stored in the at least one of the high reliability blocks to selected reserve blocks.

4. The storage system of claim 1 , wherein:
the repair parity technique writes repair parity information in selected reserve blocks, and
a number of the at least one of the high reliability blocks storing metadata is greater than a number of the reserve blocks storing the repair parity information.

5. The storage system of claim 1 , wherein the controller further comprises an interface circuit configured to communicate with the host system using a non-volatile memory express (NVMe) interface, such that the block information and the block allocation request are communicated via the interface circuit.

6. The storage system of claim 1 , wherein the storage medium includes a plurality of flash memory devices managed by a flash translation layer operating in the host system.

7. The storage system of claim 1 , wherein:
the controller further comprises a processor and a working memory accessible by the processor,
the bad block manager comprises:
a program loaded in the working memory and executed by the processor, wherein the program implements a meta region management module configured to allocate the at least one of the high reliability blocks and at least one of the reserve blocks to the meta region in response to the block allocation request; and
a bad block management module configured to manage block map information in response to a bad block determination performed on the at least one of the high reliability blocks of the meta region, and

the repair module is configured to perform a repair operation on the metadata stored in the at least one of the high reliability blocks using information stored in selected reserve blocks.

8. The storage system of claim 1 , wherein the OC-SSD is configured to receive a physical address indicating a location at which the metadata is accessed by the host system.

9. The storage system of claim 1 , when a first repair operation technique is selected from among the plurality of repair operation techniques by the host system, one reserve block is allocated corresponding to one high reliability block.

10. The storage system of claim 9 , wherein:
when a second repair operation technique is selected from among the plurality of repair operation techniques by the host system, one reserve block is allocated corresponding to at least two high reliability blocks, and
the second repair operation technique has a lower correction capability than the first repair operation technique.

11. The storage system of claim 1 , wherein the block allocation request identifies the number of reserve blocks from among the plurality of blocks used during a repair operation performed on the metadata stored in the number of the high reliability blocks.

12. The storage system of claim 1 , wherein the block allocation request identifies the number of the high reliability blocks to be used to store the metadata.

13. An operating method of a storage system including an Open-Channel Solid-State Drive (OC-SSD) having a plurality of blocks, the plurality of blocks including high reliability blocks and reserve blocks, the operating method comprising:
sending block information to a host system identifying a number of the high reliability blocks among the plurality of blocks and information indicating a plurality of repair operation techniques supported by the storage system, the host system external of the storage system;
receiving from the host system, a block allocation request identifying a high reliability block among the high reliability blocks to be allocated to a meta region where metadata is stored based on the block information sent by the storage system and a reserve block from among the reserve blocks corresponding to the high reliability block, the block allocation request further including information identifying a data mirroring technique or a repair parity technique as a selected repair operation technique, from among the plurality of repair operation techniques, selected by the host system;
allocating the high reliability block to the meta region in response to the block allocation request;
allocating the reserve block to the meta region in response to the block allocation request;
setting the selected repair operation technique, selected by the host system, as a set repair operation technique for the high reliability blocks;
selecting a different number of the reserve blocks to be allocated to the meta region based on the set repair operation technique;
writing metadata to the high reliability block in response to a metadata writing request received from the host system;
determining whether the high reliability block is a bad block;
upon determining that the high reliability block is a bad block, communicating to the host system that the high reliability block is a bad block and repairing the metadata written in the high reliability block; and
selectively accessing, when sudden power-off (SPO) occurs, the meta region and providing the metadata to the host system.

14. The operating method of claim 13 , further comprising:
writing the metadata to selected reserve blocks to mirror the metadata wr

Assignees

• Samsung Electronics Co Ltd

Inventors

• Choi Jaeyoon
• Kim Seokhwan
• Balakrishnan Suman Prakash
• Kim Dongjin
• Kim Chansol
• Rho Eunhee
• Jang Hyejeong
• Jun Walter

Classifications

• G06F3/064 Primary

  Management of blocks · CPC title

• G06F3/0619

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

• G06F3/0631

  by allocating resources to storage systems · CPC title

• G06F3/0653

  Monitoring storage devices or systems · CPC title

• G06F3/0679

  Non-volatile semiconductor memory device, e.g. flash memory, one time programmable memory [OTP] · CPC title