Operating system accessing control blocks by using home address space
segment table to control instruction and operand fetch and store
operations
    11.
    发明授权
    Operating system accessing control blocks by using home address space segment table to control instruction and operand fetch and store operations 失效
    操作系统通过使用归属地址空间段表访问控制块来控制指令和操作数获取和存储操作

    公开(公告)号:US4943913A

    公开(公告)日:1990-07-24

    申请号:US154780

    申请日:1988-02-10

    申请人: Carl E. Clark

    发明人: Carl E. Clark

    摘要: The creation of address spaces that need not map in their address range all of the routines of the operating system basic control program (BCP) is provided. The BCP, though, will have easy access to (addressability of) the home address space, i.e. to the virtually mapped and addressable control blocks therein. Addressability can be switched from a previously dispatched address space to the home address space. The dispatcher becomes capable of addressing the home address space when predetermined bits in a program status word are set. Once the home address space becomes addressable, the BCP is now capable of easily accessing control blocks in the home address space without the need to modify CPU status or pointers to any other address spaces. If pointers to any other address space are modified, current address translation in the home address space would not be affected. Providing access to the home address space increases performance and reduces complexity.

    Storage fetch protect override controls
    12.
    发明授权
    Storage fetch protect override controls 失效
    存储提取保护覆盖控件

    公开(公告)号:US4472790A

    公开(公告)日:1984-09-18

    申请号:US345961

    申请日:1982-02-05

    IPC分类号: G06F12/14 G06F9/00 G06F13/00

    CPC分类号: G06F12/1475

    摘要: The embodiment provides selective supervisory disablement of fetch protection for a special storage subarea (such as for the first half of the first 4KB block) while fetch protection is enabled for an area containing the subarea by a single storage protect key. That is, the fetch protect for the subarea (normally provided in the fetch protect for the entire area) by the area's protect key is overriden by the selective subarea disablement control, so that accesses to the subarea are not fetch protected by the storage key. The override protection control is secured by its enablement via a field position in a control register only accessible to supervisory programming. Thus, while fetch protection is set on for a predefined 4KB block, the fetch protect override controls can disable the fetch protection for a portion of the block's real addresses (e.g. addresses 0-2047).

    摘要翻译: 该实施例提供了对于特殊存储子区域(例如,对于第一4KB块的前半部分)的提取保护的选择性监控禁用,同时通过单个存储保护密钥对包含子区域的区域进行提取保护。 也就是说,区域的保护密钥对子区域(通常在整个区域的提取保护中通常提供的保护)的提取保护被选择性区域禁用控制覆盖,使得对子区域的访问不被存储密钥的保护保护。 超控保护控制通过其通过控制寄存器中的现场位置来实现,只能用于监控编程。 因此,虽然为预定义的4KB块设置了提取保护,但是提取保护覆盖控制可以禁止块的一部分实际地址(例如地址0-2047)的提取保护。