Access control method, access control apparatus, and computer-readable memory storing access control program
AssigneeCanon Kabushiki Kaisha
InventorSHIGEO SUZUKI
Life of this patent
Estimating the term…
Abstract
A file manager and buffer cache manager generate access information for accessing a flash ROM in units of blocks on the basis of an access request designated by a user program. When the access request is a data read request, a flash disk driver calculates an access address to the flash ROM on the basis of a block designated by the access information, and sends back the calculated access address to the buffer cache manager. The buffer cache manager reads out data from the flash ROM using the received access address, and directly transfers the obtained data to a memory area managed by the user program.
Claims21
An access control method for accessing a storage medium capable of being directly accessed by designating memory address and a buffer for temporarily holding contents of the storage medium, comprising:
- the generation step of generating block access information for accessing the storage medium in units of blocks on the basis of an access request designated by a user program;
- the calculation step of calculating an access address to the storage medium on the basis of an access destination block designated by the block access information;
- the copying step of, when the access request is a data read request, accessing, on the basis of the data read request, the storage medium using the block access information generated in the generation step and the access address calculated in the calculation step, and copying obtained data to a memory area managed by the user program;
- and
- the write step of, when the access request is a data write request, writing data on the basis of the data write request via the buffer using the block access information generated in the generation step and the access address calculated in the calculation step.
An access control apparatus for accessing a storage medium capable of being directly accessed by designating memory address and a buffer for temporarily holding contents of the storage medium, comprising:
- generation means for generating block access information for accessing the storage medium in units of blocks on the basis of an access request designated by a user program;
- calculation means for calculating an access address to the storage medium on the basis of an access destination block designated by the block access information;
- copying means for, when the access request is a data read request, accessing, on the basis of the data read request, the storage medium using the block access information generated by said generation means and the access address calculated by said calculation means, and copying obtained data to a memory area managed by the user program;
- and
- write means for, when the access request is a data write request, writing data on the basis of the data write request via the buffer using the block access information generated by said generation means and the access address calculated by said calculation means.
A computer-readable memory storing a control program for realizing, by a computer, access control for accessing a storage medium capable of being directly accessed by designating memory address and a buffer for temporarily holding contents of the storage medium, the control program comprising:
- a code of the generation step of generating block access information for accessing the storage medium in units of blocks on the basis of an access request designated by a user program;
- a code of the calculation step of calculating an access address to the storage medium on the basis of an access destination block designated by the block access information;
- a code of the copying step of, when the access request is a data read request, accessing, on the basis of the data read request, the storage medium using the block access information generated in the generation step and the access address calculated in the calculation step, and copying obtained data to a memory area managed by the user program;
- and
- a code of the write step of, when the access request is a data write request, writing data on the basis of the data write request via the buffer using the block access information generated in the generation step and the access address calculated in the calculation step.
Dependencies are inferred from the claim text.