Storage controller performing active zone refresh, method of operating storage controller, and method of operating storage device having storage controller

Patent metadata

Field	Value
Publication number	US-12417052-B2
Application number	US-202217970628-A
Country	US
Kind code	B2
Filing date	Oct 21, 2022
Priority date	Jan 26, 2022
Publication date	Sep 16, 2025
Grant date	Sep 16, 2025

Abstract

Disclosed is a method of operating a storage controller which communicates with a host and a non-volatile memory device. The method includes receiving a first state transition request for a device open from the host, performing a first active zone refresh operation of the non-volatile memory device in response to the first state transition request such that a zone, which has an active state before an immediately previous power-off is processed to a sequentially writable state in one block, receiving, by a first buffer memory, first target data to be stored in a first block of a first zone among the plurality of zones from the host depending on a first write request, receiving a first power-off request from the host, during processing the first write request, and storing the first target data in a first power loss protection (PLP) block of the non-volatile memory device.

First claim

What is claimed is:

1. A method of operating a storage controller configured to communicate with a host and a non-volatile memory device, the method comprising:
receiving, from the host, a first state transition request for a device open;
performing a first active zone refresh operation of the non-volatile memory device in response to the first state transition request such that at least one zone, from among a plurality of zones of the non-volatile memory device and which has an active state before an immediately previous power-off, is processed to a sequentially writable state in at least one block;
receiving, by a first buffer memory, first target data to be stored in a first block of a first zone, among the plurality of zones, based on a first write request received from the host after performing the first active zone refresh operation;
receiving a first power-off request from the host before the first write request is completed; and
storing the first target data remaining in the first buffer memory in a first power loss protection (PLP) block of the non-volatile memory device, instead of the first block, based on receiving the first power-off request,
wherein the performing of the first active zone refresh operation of the non-volatile memory device in response to the first state transition request includes
copying user data of a block of a zone, which is allocated before the immediately previous power-off, to a newly allocated block, and
copying, sequentially to the copying of the user data, corresponding target data of a corresponding PLP block using a corresponding write pointer.

2. The method of claim 1 , wherein the first PLP block has a higher reliability than the first block.

3. The method of claim 1 , wherein the user data stored in the first block include a plurality of programming units which are logically and physically sequential, and
wherein a logical block address of a last programming unit of the plurality of programming units is an address immediately before a logical block address of the first target data.

4. The method of claim 1 , further comprising:
receiving, by a second buffer memory, second target data to be stored in a second block of a second zone, among the plurality of zones, based on a second write request received from the host after performing the first active zone refresh operation; and
storing the second target data in a second PLP block of the non-volatile memory device, instead of the second block, based on the first power-off request,
wherein the first power-off request is received before the first write request and the second write request is completed.

5. The method of claim 1 , further comprising:
completing the first power-off request after storing the first target data in the PLP block;
receiving, from the host, a second state transition request for the device open after the first power-off request is completed;
performing a second active zone refresh operation of the non-volatile memory device in response to the second state transition request such that the first zone, which has the active state before the first power-off request is completed, is processed to a sequentially writable state in a third block newly allocated; and
receiving, by the first buffer memory, third target data to be stored in the third block based on a third write request received from the host after performing the second active zone refresh operation.

6. The method of claim 5 , further comprising:
receiving, by the first buffer memory, fourth target data to be stored in the third block based on the third write request received from the host, wherein the fourth target data are sequential to the third target data and the first buffer memory is filled with the third target data and the fourth target data; and
sequentially storing the third target data and the fourth target data of the first buffer memory in the third block.

7. The method of claim 5 , further comprising:
receiving a second power-off request from the host, before the third write request is completed; and
storing the third target data in a third PLP block of the non-volatile memory device, instead of the third block, based on the second power-off request.

8. The method of claim 5 , wherein the performing of the second active zone refresh operation of the non-volatile memory device in response to the second state transition request includes:
determining whether the first zone has the active state before the first power-off request is completed;
allocating the third block of the first zone when it is determined that the first zone has the active state before the first power-off request is completed;
copying user data of the first block of the first zone to the third block; and
copying the first target data of the first PLP block, immediately after the copying of the user data of the third block, using a write pointer, and
wherein a logical block address of the third target data is immediately after a logical block address of the copied first target data.

9. The method of claim 8 , further comprising:
discarding the first block after copying the user data of the first block to the third block.

10. The method of claim 1 , wherein the performing of the first active zone refresh operation of the non-volatile memory device in response to the first state transition request includes:
setting a zone identification number to an initial value in response to the first state transition request; and
determining whether a zone corresponding to the set zone identification number, from among the plurality of zones, has the active state before the immediately previous power-off,
wherein the copying the user data includes copying the user data of a block of the corresponding zone, which is allocated before the immediately previous power-off, to a newly allocated block when it is determined that the corresponding zone has the active state before the immediately previous power-off, and
wherein the sequentially copying the corresponding target data includes copying the corresponding target data of a corresponding PLP block immediately after the copied user data of the newly allocated block using a corresponding write pointer.

11. The method of claim 10 , wherein the performing of the first active zone refresh operation of the non-volatile memory device in response to the first state transition request further includes:
determining whether the set zone identification number is a last value after copying the corresponding target data of the corresponding PLP block;
setting, again, the set zone identification number to a value increased by a unit size when it is determined that the set zone identification number is not the last value; and
determining whether a zone corresponding to the again set zone identification number from among the plurality of zones has the active state before the immediately previous power-off.

12. The method of claim 1 , wherein the storing of the first target data in the first PLP block of the non-volatile memory device includes:
storing a write pointer indicating a logical block address of the first target data; and
storing zone block information indicating that the first block is allocated to the first zone.

13. The method of claim 1 , wherein the storage controller supports a zoned namespace (ZNS) standard of a non-volatile memory (NVM) express.

14. The method of claim 13 , wherein the first state transition request indicates a transition to at least one of an implicitly opened zone (ZSIO) state or an explicitly opened zone (ZSEO) state of the ZNS standard, and
wherein the active state includes the ZSIO s

Assignees

• Samsung Electronics Co Ltd

Inventors

• Son Minsik
• Kim Hyunkoo
• Park Junseok
• Kim Suhwan

Classifications

• G06F3/0625

  Power saving in storage systems · CPC title

• G06F3/0679 Primary

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

• G06F12/0238

  Memory management in non-volatile memory, e.g. resistive RAM or ferroelectric memory · CPC title

• G06F2212/1032

  Reliability improvement, data loss prevention, degraded operation etc · CPC title

• G06F2212/7208

  Multiple device management, e.g. distributing data over multiple flash devices · CPC title