Method and device for realizing safety operation of file system

The embodiment of the invention discloses a method and a device for realizing safety operation of a file system. The method comprises the following steps: before an operating system is started, a first copy catalogue for a first source catalogue is established, wherein the first source catalogue is positioned in a read-only partition of a magnetic disk, and the first copy catalogue is positioned in a read-write partition of the magnetic disk; when the file system is started, the first copy catalogue and the first source catalogue are bound, so that when the operating system runs, the operation on the first source catalogue is actually executed on the first copy catalogue; after binding is finished, the read-write state of the read-only partition is reset into a read-only state, and the read-write state of the read-write partition is maintained, so that the reset first source catalogue only supports read operation, and the first copy catalogue can support both read operation and write operation at the same time. According to the method and the device for realizing the safety operation of the file system, when the system needs to perform the write operation on any catalogue positioned in the read-only partition, the catalogue can support the write operation from the system on files under the catalogue.