Dynamic Address Translation Format Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current dynamic address translation facilities lack enhanced functionality, capability, and protection mechanisms, limiting their ability to efficiently manage and secure virtual address translations in computer systems with hierarchical translation tables.
Innovation Solution
An enhanced dynamic address translation facility that translates virtual addresses into real or absolute addresses by utilizing a hierarchy of translation tables, including a segment table entry format control to determine whether a segment frame absolute address is used, and employing access control and fetch protection bits to restrict access to specific blocks of data.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If traditional dynamic address translation is used, then basic virtual address translation is achieved, but functionality and security capabilities are limited
Solution Approach 1:
The translation facility is segmented into multiple independent components: format control field, access control bits, fetch protection bits, and large block identification. Each segment performs a specific function (format selection, access permission, fetch protection, block size identification) that can be independently configured and managed, allowing enhanced functionality without proportionally increasing overall complexity
Solution Approach 2:
The translation facility dynamically adapts its behavior based on the format control field. When format control is enabled, the system switches to a different translation mode that supports large blocks with access and fetch protection. This dynamic switching allows the facility to provide enhanced functionality only when needed, rather than always operating in the complex mode
2Reliability
If access control and fetch protection bits are added, then security is improved, but device complexity increases
Solution Approach 1:
Access control bits and fetch protection bits are merged into the same translation table entry structure, along with the format control field and large block identification. This consolidation allows multiple security and control functions to be implemented within a single unified data structure, improving security without requiring separate complex mechanisms for each function
Solution Approach 2:
Different protection mechanisms (access control, fetch protection) are applied locally to specific translation table entries based on the format control field. Only entries with format control enabled receive the enhanced protection treatment, allowing security to be applied selectively where needed rather than uniformly across all translations
3Productivity
If large blocks of data are accessed, then access efficiency is improved, but address translation complexity increases
Solution Approach 1:
The system changes the block size parameter from traditional small pages to large blocks when the format control field is enabled. This parameter change allows larger data blocks to be accessed in single operations, improving productivity. The large block identification field provides the necessary information to handle these larger blocks without requiring complex additional translation mechanisms
Data Source
Figure 1
Figure 2
Figure 3
AI summary
What is provided is an enhanced dynamic address translation facility. In one embodiment, a virtual address to be translated and an initial origin address of a translation table of the hierarchy of translation tables are obtained. An index portion of the virtual address is used to reference an entry in the translation table. If the format control field is enabled, a frame address of a large block of data in main storage is obtained from the translation table entry. The large block of data is a block of at least 1M byte in size. The frame address is then combined with an offset portion of the virtual address to form the translated address of a desired block of data within the large block of data in main storage. The desired large block of data addressed by the translated address is then accessed.