A method of deep erasing flash files online

Abstract

The invention relates to the technical field of data storage, in particular to a method for deeply erasing an FLASH file online. The method comprises the following steps of adding a FLASH independent partition and a deep erasure function for the independent partition to a linux kernel, and adding an independent partition deep erasure application to an application space; re-compiling the linux kernel and performing updating to an embedded target board; after a linux system is started up, automatically mounting the added FLASH independent partition; and when file data needs to be erased, uninstalling the mounting of the independent partition by a system user, calling the independent partition deep erasure application to realize deep erasure of the file data of the independent partition, and re-mounting the independent partition to a file system directory by the system user, thereby obtaining the independent partition without any file. According to the method, the deep erasure function can take effect only when being called, so that normal use of other partitions of the system is not influenced, the operation is convenient, the file data in the whole independent partition can be deeply erased, and the risk of file data leakage is avoided.

Description

technical field [0001] The invention relates to the technical field of data storage, in particular to a method for online deep erasing of FLASH files. Background technique [0002] In the embedded linux system, FLASH (flash memory) is used as a non-volatile storage device for files, usually including NAND FLASH (and non-type) and NOR FLASH (or non-type). The linux kernel builds a file system on the basis of the FLASH hardware device and provides a file operation interface for the upper application layer. The interface seen by the user at the application layer is an independent file, which can be used to create, edit, save, and delete files. [0003] At present, there are three main methods of erasing FLASH files: [0004] When the main processing chip is in the emulation state, send an erase command to the FLASH chip to erase the entire partition occupied by the file; [0005] Use the file delete command under the file system to delete the file; [0006] Find the real st...

AI Technical Summary

Problems solved by technology

[0008] The method of erasing FLASH data in the emulation state of the main processing chip must power on the main processing chip again, so that the chip is in the emulation state, which does not meet the requirements of erasing file data online;

[0009] Using the file delete command under the file system to delete a file can only delete the file index information, but cannot actually delete the file data information;

[0010] Find the real storage location of the file data based on the jffs2 file node header information. The method of erasing the FLASH block cannot completely delete the historical data: In the jffs2 file system, in order to prolong the service life of the FLASH, the MTD (memory technology device) management layer uses the erasure Equilibrium mechanism and garbage collection mechanism, which cause the movement of file data

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