A file access method, comprising: receiving a file access request from a process, wherein the file access request comprises a file identifier, and the file identifier is used to indicate a to-be-accessed target file; accessing a first physical address space according to a preset first virtual address space and a preset first mapping relationship between the first virtual address space and the first physical address space, wherein the first virtual address space is a part of user space in an operating system, and the first physical address space stores a file system and is a part of memory space; obtaining an index node of the target file from the first physical address space according to the file identifier of the target file, wherein the index node comprises file page table information of the target file; obtaining a file page table of the target file according to the file page table information, comprised in the index node, of the target file, wherein the file page table records a second physical address space in the first physical address space, a data page of the target file is stored in the second physical address space, and the data page of the target file is used to store file data; and accessing the target file according to the second physical address space. characterized in that the accessing the target file according to the second physical address space comprises: allocating a second virtual address space to the target file, wherein the second virtual address space is a part of private space, allocated to the process, in the user space in the operating system, and the second virtual address space is a contiguous address space; establishing a second mapping relationship between the second physical address space and the second virtual address space by linking the file page table of the target file to a process page table corresponding to the second virtual address space; and accessing the target file in the second physical address space according to the second virtual address space and the second mapping relationship. receiving a file access request from a process, wherein the file access request comprises a file identifier, and the file identifier is used to indicate a to-be-accessed target file; accessing a first physical address space according to a preset first virtual address space and a preset first mapping relationship between the first virtual address space and the first physical address space, wherein the first virtual address space is a part of user space in an operating system, and the first physical address space stores a file system and is a part of memory space; obtaining an index node of the target file from the first physical address space according to the file identifier of the target file, wherein the index node comprises file page table information of the target file; obtaining a file page table of the target file according to the file page table information, comprised in the index node, of the target file, wherein the file page table records a second physical address space in the first physical address space, a data page of the target file is stored in the second physical address space, and the data page of the target file is used to store file data; and accessing the target file according to the second physical address space. characterized in that the accessing the target file according to the second physical address space comprises: allocating a second virtual address space to the target file, wherein the second virtual address space is a part of private space, allocated to the process, in the user space in the operating system, and the second virtual address space is a contiguous address space; establishing a second mapping relationship between the second physical address space and the second virtual address space by linking the file page table of the target file to a process page table corresponding to the second virtual address space; and accessing the target file in the second physical address space according to the second virtual address space and the second mapping relationship.