Figure 5-30: Regular paging
In extended paging, 32 bits of linear address are divided into two fields:
•Directory: The most significant 10 bits represents directory.
•Offset: The remaining 22 bits represents offset.
Figure 5-31: Extended paging
Each entry of the page directory and of the page table is represented by the same data structure. This data structure includes fields that describe the page table or page entry, such as accessed flag, dirty flag, and page size flag. The two important flags for access control are the Read/Write flag and the User/Supervisor flag.
Read/Write flag: Holds access rights of the page or the page table. The Read/Write flag is either read/write or read. If set to 0, the corresponding page or page table can only be read; otherwise, the corresponding page table can be written to or read.
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