WO2018209733A1

WO2018209733A1 - Serial flash data protection method and device

Info

Publication number: WO2018209733A1
Application number: PCT/CN2017/086340
Authority: WO
Inventors: 漆湘明; 蒋周金; 张友运; 赵峰; 刘再乐; 瞿诗琦; 肖箭鑫; 陈坤; 刘宏军; 刘玲; 黎健英; 熊文龙; 贺佐旺; 常俊山; 吴臣国
Original assignee: 瑞斯康微电子（深圳）有限公司
Priority date: 2017-05-19
Filing date: 2017-05-27
Publication date: 2018-11-22
Also published as: CN107273309A

Abstract

Disclosed are a serial flash data protection method and device, and the method comprises: dividing a serial flash into a cache area and an actual area on the basis of a logical address; establishing page mapping between the cache area and the actual area; writing, in an area by area manner, data to be written to a mapped sector of the cache area, and if there is insufficient space in remaining mapping sectors of the cache area or sector transfer is required for data, writing data in the mapped sector to the actual area, and when data writing is completed, wiping the mapped sector corresponding to the cache area and removing the page mapping relationship. The device is used to execute the corresponding method; by setting up the cache area and the actual area and performing data transfer by means of page mapping, data transfer is performed if there is a cache area overflow or specific data is required to be transferred; data erasure is only performed after data is completely transferred, ensuring data preservation in a power outage scenario.

Description

Serial flash data protection method and device

Technical field

The invention relates to a serial flash data protection method and device, belonging to the field of computers.

Background technique

Serial FALSH memory is widely used in microcontroller product development environments due to its simple interface and large capacity. However, its relatively slow read and write speeds lead to a high probability of file loss during the data write operation phase, and even the entire file system crashes.

There are usually two ways to solve this problem in the existing stage: First, make up for the hardware, such as power-down protection circuit and other strategies; this method largely solves the problem of data loss caused by accidental power failure, but it involves There are too many technical links, and the software also needs to cooperate, so it is impossible to guarantee its reliability 100%. The biggest shortcoming is that the protection circuit will greatly increase the product development cost (hardware cost).

Summary of the invention

In order to solve the above problems, the present invention provides a device for serial flash data protection.

The technical solution adopted by the present invention is a serial flash data protection method, which comprises the steps of: dividing a serial flash memory into a buffer area and an actual area based on a logical address; establishing a page mapping between the buffer area and the actual area; The write data is written to the mapped sector of the buffer area by region. When the space of the remaining mapped sectors of the buffer area is insufficient or the data needs to be converted, the data of the mapped sector is written into the actual area, and when the data is written. When, the mapped sector corresponding to the buffer area is wiped and the page mapping relationship is removed.

Preferably, the method further includes the steps of: obtaining an absolute address of an actual area in which data needs to be written, querying whether the absolute address has a corresponding mapped sector in the buffer area, and if not, determining a mapping sector and establishing the mapping area The page mapping of the absolute address; if present, the data of the mapped sector is read and stored in the RAM, which is used to store the data to be written to the actual area.

Preferably, when the space of the remaining mapped sectors of the buffer area is insufficient, the RAM reads data from the mapped sector in which the data has been written, writes the data to the actual area based on the page mapping, and wipes the buffer when the data writing is completed. The mapped sector corresponding to the area and the page mapping relationship is removed.

Preferably, when a sector needs to be converted, the RAM reads data from the corresponding mapped sector, writes data to the actual area based on the page mapping, and when the data writing is completed, wipes the mapped sector corresponding to the buffer area and removes the page mapping. relationship.

Another aspect of the technical solution adopted by the present invention is a serial flash data protection device, which includes the following modules:

a dividing module, configured to divide the serial flash memory into a buffer area and an actual area based on the logical address; a mapping module, configured to establish a page mapping between the buffer area and the actual area; and a data processing module, configured to write the data to be written area by area The mapped sector into the buffer area, when the remaining mapped sectors of the buffer area have insufficient space or the data needs to be converted, the data of the mapped sector is written. In the actual area, when the data is written, the mapped sector corresponding to the buffer area is wiped and the page mapping relationship is removed.

Preferably, the mapping module is further configured to obtain an absolute address of an actual area in which data needs to be written, and query whether the absolute address has a corresponding mapping sector in the buffer area, and if not, determine a mapping sector and establish and The page mapping of the absolute address; if present, the data of the mapped sector is read and stored in a RAM, and the RAM is used to store data to be written into the actual area.

Preferably, the data processing module is further configured to: when the space of the remaining mapped sectors of the buffer area is insufficient, the RAM reads data from the mapped sector in which the data has been written, and writes the data into the actual area based on the page mapping, When the data writing is completed, the mapping sector corresponding to the buffer area is wiped and the page mapping relationship is removed.

Preferably, the data processing module is further configured to: when the sector needs to be converted, the RAM reads data from the corresponding mapped sector, writes the data to the actual area based on the page mapping, and wipes the buffer area when the data writing is completed. Corresponding mapping sectors and tear down the page mapping relationship.

The beneficial effects of the present invention are that data is transferred by page mapping by setting a buffer area and an actual area, and data is transferred when a buffer area overflows or a specific data transfer is required, only when the data is completely transferred. Data is cleared to ensure that data can be saved while the power is off.

DRAWINGS

FIG. 1 is a schematic diagram of a serial flash data protection method based on an embodiment of the present invention.

detailed description

The invention will now be described in connection with the examples.

According to Embodiment 1 of the invention, a serial flash data protection method as shown in FIG. 1 includes the steps of: dividing a serial flash memory into a buffer area and an actual area based on a logical address; and establishing a page mapping between the buffer area and the actual area. Writing the data to be written to the mapped sector of the buffer area by region. When the space of the remaining mapped sectors of the buffer area is insufficient or the data needs to be converted, the data of the mapped sector is written into the actual area, when the data is When the writing is completed, the mapping sector corresponding to the buffer area is wiped and the page mapping relationship is removed.

The program is divided into a buffer area and an actual area by using a program (based on logical address division), and the actual area is a space for finally storing data, and the storage area is allocated by the buffer area and the actual area in the form of page storage. Establish a page mapping between the two, that is, the correspondence between the page and the page (the mapping record is made into a mapping table, including the sector number, the corresponding physical address and logical address, etc.); and the step of writing the data, One step is that the external data to be written is first stored in the buffer area by page (ie, the mapped sector). Since the setting of the buffer area is program controlled, the usage record of the sector number of the mapped sector can be used. Knowing the use of the sector, when there is no redundant mapped sector in the buffer area or when the data of the buffer area needs to be stored in the actual area, the data is moved according to the page mapping relationship between the mapped sectors, when the data is written. Upon completion, the data of the corresponding mapped sector of the buffer area is wiped and the page mapping relationship is removed.

A serial flash data protection method according to Embodiment 1 of the invention further includes the following steps: acquiring the number of writes required According to the absolute address of the actual area, query whether the absolute address has a corresponding mapped sector in the buffer area, if not, determine a mapping sector and establish a page mapping with the absolute address; if it exists, read The data of the mapped sector is stored in a RAM for storing data to be written into the actual area.

When the data needs to be written to an absolute address of the actual area, the mapping table of the page mapping is established by querying, and it can be known whether there is already a set mapping relationship. If it exists, it is not necessary to re-establish the mapping relationship. Transfer data directly through the memory, if not, then determine a mapped sector in the buffer area (may be the part that has not been written data, or the part obtained after wiping); obtain the mapped sector The data is stored in RAM.

According to a serial flash data protection method of Embodiment 1 of the invention, when the space of the remaining mapped sectors of the buffer area is insufficient, the RAM reads data from the mapped sector in which the data has been written, and writes the data based on the page mapping. In the actual area, when the data is written, the mapped sector corresponding to the buffer area is wiped and the page mapping relationship is removed.

It is easy to know the usage of the flash space by data writing or wiping the record. When the remaining mapped sectors of the buffer area (that is, the sectors without data are stored) or the sector space is insufficient, the written data is acquired. The data of the sector, select several of the sectors for data transfer (the sector can be randomly selected or the oldest sector in the order of data write time), when the data is written, the buffer is wiped Corresponding sectors and remove page mapping relationships.

According to a serial flash data protection method of Embodiment 1 of the invention, when a sector needs to be converted, the RAM reads data from the corresponding mapped sector, and writes data to the actual area based on the page mapping, when the data writing is completed. , wipe the mapping sector corresponding to the buffer area and remove the page mapping relationship.

Since specific data needs to be transferred, data is transferred from a specific sector, data is read from a specific mapped sector through RAM, and then data is written to a sector corresponding to the actual area based on the relationship of page mapping. / page, when the data is written, the corresponding sector of the buffer area is wiped and the page mapping relationship is removed.

According to Embodiment 2 of the present invention, a serial flash data protection device includes the following modules:

a dividing module, configured to divide the serial flash memory into a buffer area and an actual area based on the logical address; a mapping module, configured to establish a page mapping between the buffer area and the actual area; and a data processing module, configured to write the data to be written area by area The mapped sector of the buffer area is written into the actual area when the remaining mapped sectors of the buffer area are insufficient or the data needs to be converted into sectors. When the data is written, the wipe buffer area corresponds to Map the sectors and remove the page mapping relationship.

According to a serial flash data protection device of Embodiment 2 of the present invention, the mapping module is further configured to acquire an absolute address of an actual area in which data needs to be written, and query whether the absolute address has a corresponding mapped sector in the buffer area. If not, determining a mapped sector and establishing a page mapping with the absolute address; if present, reading the data of the mapped sector and storing the RAM, the RAM for storing the actual area to be written The data.

According to a serial flash data protection device of Embodiment 2 of the present invention, the data processing module is further configured to: when the space of the remaining mapped sectors of the buffer area is insufficient, the RAM is from the mapped sector of the written data. Read data based on page mapping The data is written into the actual area. When the data is written, the mapped sector corresponding to the buffer area is wiped and the page mapping relationship is removed.

A serial flash data protection apparatus according to Embodiment 2 of the present invention, wherein the data processing module is further configured to: when a sector needs to be converted, the RAM reads data from a corresponding mapped sector, and writes data based on the page mapping. In the actual area, when the data is written, the mapped sector corresponding to the buffer area is wiped and the page mapping relationship is removed.

The above is only a preferred embodiment of the present invention, and the present invention is not limited to the above embodiment, and as long as it achieves the technical effects of the present invention by the same means, it should fall within the scope of protection of the present invention. Various modifications and changes may be made to the technical solutions and/or embodiments within the scope of the invention.

Claims

A serial flash data protection method, comprising the steps of:

The serial flash memory is divided into a buffer area and an actual area based on the logical address;

Establish a page mapping between the buffer area and the actual area;

Write the data to be written to the mapped sector of the buffer area by region. When the space of the remaining mapped sectors in the buffer area is insufficient or the data needs to be converted, the data of the mapped sector is written into the actual area, when the data is written. When the input is complete, wipe the mapping sector corresponding to the buffer area and remove the page mapping relationship.
A serial flash data protection method according to claim 1, further comprising the steps of:

Obtaining an absolute address of the actual area where the data needs to be written, querying whether the absolute address has a corresponding mapped sector in the buffer area, and if not, determining a mapping sector and establishing a page mapping with the absolute address;

If present, the data of the mapped sector is read and stored in RAM, which is used to store data to be written to the actual area.
A serial flash data protection method according to claim 2, wherein when the space of the remaining mapped sectors of the buffer area is insufficient, the RAM reads data from the mapped sectors of the written data, based on the page. The mapping writes the data to the actual area. When the data is written, the mapping sector corresponding to the buffer area is wiped and the page mapping relationship is removed.
A serial flash data protection method according to claim 2, wherein when a sector needs to be converted, the RAM reads data from the corresponding mapped sector, and writes the data to the actual area based on the page mapping, when the data When the writing is completed, the mapping sector corresponding to the buffer area is wiped and the page mapping relationship is removed.
A serial flash data protection device, comprising the following modules:

a dividing module, configured to divide the serial flash memory into a buffer area and an actual area based on the logical address;

a mapping module, configured to establish a page mapping between the buffer area and the actual area;

a data processing module, configured to write the data to be written into the mapped sector of the buffer area by region, and write the data of the mapped sector when the space of the remaining mapped sectors of the buffer area is insufficient or the data needs to be converted into a sector. In the actual area, when the data is written, the mapped sector corresponding to the buffer area is wiped and the page mapping relationship is removed.
The serial flash data protection device according to claim 5, wherein the mapping module is further configured to acquire an absolute address of an actual area in which data needs to be written, and query whether the absolute address has a corresponding area in the buffer area. Mapping a sector, if not present, determining a mapped sector and establishing a page mapping with the absolute address;

If present, the data of the mapped sector is read and stored in RAM, which is used to store data to be written to the actual area.
The serial flash data protection device according to claim 6, wherein the data processing module is further configured to: when the space of the remaining mapped sectors of the buffer area is insufficient, the RAM is written from the data. The mapping sector reads data, and the data is written into the actual area based on the page mapping. When the data writing is completed, the mapping sector corresponding to the buffer area is wiped and the page mapping relationship is removed.
A serial flash data protection device according to claim 6, wherein said data processing module, Also used when the sector needs to be converted, the RAM reads data from the corresponding mapped sector, writes the data to the actual area based on the page mapping, and when the data is written, wipes the mapped sector corresponding to the buffer area and tears down the page mapping. relationship.