Memory management device, image forming apparatus, and image forming method

1. A memory management device that has a virtual memory space and that manages a memory region, the memory management device comprising:

an OS-management-memory-region managing unit configured to divide a physical memory space into a management region that can be managed by an OS and a non-management region that is not managed by the OS, assign the management region to the virtual memory space, and perform at least one of acquiring and freeing a memory space included in the management region;

an OS-non-management-memory-region managing unit configured to assign the non-management region to the virtual memory space so that an application program performs at least one of acquiring and freeing a memory space included in the non-management region; and

a window region provided to cause the OS-management-memory-region managing unit to refer the OS to the non-management region,

wherein data is read from and written into the non-management region of the physical memory space via the window region.

2. An image forming apparatus comprising:

an OS-management-memory-region managing unit configured to divide a physical memory space into a management region that can be managed by an OS and a non-management region that is not managed by the OS, assign the management region to a virtual memory space, and perform at least one of acquiring and freeing a memory space included in the management region;

an OS-non-management-memory-region managing unit configured to assign the non-management region to the virtual memory space so that an application program perform at least one of acquiring and freeing a memory space included in the non-management region; and

a window region provided so that the OS-management-memory-region managing unit makes the OS refer to the non-management region,

wherein data is read from and written into the OS-non-management region of the physical memory space via the window region.

3. The image forming apparatus according to claim 2 , further comprising:

a DMA transfer unit configured so that hardware can directly access a memory space of the non-management region.

4. The image forming apparatus according to claim 3 , further comprising:

a scanner unit configured to read and convert an image into image data,

wherein the DMA transfer unit writes the converted image data onto the non-management region through DMA-transfer.

5. The image forming apparatus according to claim 3 , further comprising:

a universal-serial-bus connection unit configured to receive image data transmitted from an externally connected universal-serial-bus memory,

wherein the DMA transfer unit writes the received image data onto the non-management region through DMA-transfer.

6. The image forming apparatus according to claim 3 , further comprising:

a facsimile reception unit configured to receive image data transmitted through a facsimile communication line,

wherein the DMA transfer unit writes the received image data onto the non-management region through DMA-transfer.

7. The image forming apparatus according to claim 3 , further comprising:

a print data reception unit configured to receive image data transmitted from an information processing device provided outside the image forming apparatus,

wherein the DMA transfer unit writes the received image data onto the non-management region through DMA-transfer.

8. An image forming method comprising:

an OS-management-memory-region managing step performed to divide a physical memory space into a management region that can be managed by an OS and a non-management region that is not managed by the OS, assign the management region to a virtual memory space, and perform at least one of acquiring and freeing a memory space included in the management region;

an OS-non-management-memory-region managing step performed to assign the non-management region to the virtual memory space so that an application program performs at least one of acquiring and freeing a memory space included in the non-management region; and

a window region referring step performed so that the OS refers to the non-management region in a window region included in an OS-management-memory region,

wherein data is read from and/or written into the OS-non-management region of the physical memory space via the window region.

9. The image forming method according to claim 8 , further comprising:

a DMA transfer step performed so that hardware can directly access a memory space of the non-management region.

10. The image forming method according to claim 9 , further comprising:

a scanner step performed to read and convert image into image data,

wherein, at the DMA transfer step, the converted image data is written onto the non-management region through DMA-transfer.

11. The image forming method according to claim 9 , further comprising:

a universal-serial-bus reception step performed to receive image data transmitted from a universal-serial-bus memory connected from outside an image forming apparatus,

wherein, at the DMA transfer step, the received image data is written onto the non-management region through DMA-transfer.

12. The image forming method according to claim 9 , further comprising:

a facsimile reception step performed to receive image data transmitted through a facsimile communication line,

wherein, at the DMA transfer step, the received image data is written onto the non-management region through DMA-transfer.

13. The image forming method according to claim 9 , further comprising:

a print data reception step performed to receive image data transmitted from an information processing device provided outside an image forming apparatus,

wherein, at the DMA transfer step, the received image data is written onto the non-management region through DMA-transfer.