Abstract:
Selected units of storage, such as segments of storage or regions of storage, are invalidated. The invalidation is facilitated by the setting of invalidation indicators located in data structure entries corresponding to the units of storage to be invalidated. Additionally, buffer entries associated with the invalidated units of storage or other chosen units of storage are cleared. An instruction is provided to perform the invalidation and/or clearing. Moreover, buffer entries associated with a particular address space are cleared, without any invalidation. This is also performed by the instruction. The instruction can be implemented in software, hardware, firmware or some combination thereof, or it can be emulated.
Abstract:
Management of storage used by pageable guests of a computing environment is facilitated. An enhanced suppression-on-protection facility is provided that enables the determination of which level of protection (host or guest) caused a fault condition, in response to an attempted storage access.
Abstract:
What is provided is an enhanced dynamic address translation facility. In one embodiment, a virtual address to be translated is first obtained and an initial origin address of a translation table of the hierarchy of translation tables is obtained. Based on the obtained initial origin, a segment table entry is obtained. The segment table entry is configured to contain a format control and access validity fields. If the format control and access validity fields are enabled, the segment table entry further contains an access control field, a fetch protection field, and a segment-frame absolute address. Store operations are permitted only if the access control field matches a program access key provided by any one of a Program Status Word or an operand of a program instruction being executed. Fetch operations are permitted if the program access key associated with the virtual address is equal to the segment access control field.
Abstract:
An instruction is provided to perform a reset address translation protection operation when executed. Executing the instruction includes determining, by a processor, that an address translation protection bit in a specified translation table entry associated with a storage block is to be reset. Based on determining that the address translation protection bit is to be reset, executing the instruction includes resetting the address translation protection bit to deactivate write protection for the storage block. The resetting is absent waiting for an action by one or more other processors of the computing environment.
Abstract:
A method is provided. The method is implemented by a secure interface control of a computer that prevents unauthorized accesses to locations in a memory of the computer. The secure interface control determines that a host absolute page is not previously mapped to a virtual page in accordance with securing the host absolute page and a host virtual page is not already mapped to an absolute page in accordance with securing the host absolute page.
Abstract:
A method is provided. A secure interface control in communication with an untrusted entity perform the method. In this regard, the secure interface control implements an initialization instruction to set donated storage as secure. The implementing of the initialization instruction is responsive to an instruction call issued from the untrusted entity.
Abstract:
According to one or more embodiments of the present invention, a computer implemented method includes initiating, by a non-secure entity that is executing on a host server, a secure entity, the non-secure entity prohibited from directly accessing any data of the secure entity. The method further includes injecting, into the secure entity, an interrupt that is generated by the host server. The injecting includes adding, by the non-secure entity, information about the interrupt into a portion of non-secure storage, which is then associated with the secure entity. The injecting further includes injecting, by a secure interface control of the host server, the interrupt into the secure entity.
Abstract:
A system and method of implementing a modified priority routing of an input/output (I/O) interruption. The system and method determines whether the I/O interruption is pending for a core and whether any of a plurality of guest threads of the core is enabled for guest thread processing of the interruption in accordance with the determining that the I/O interruption is pending. Further, the system and method determines whether at least one of the plurality of guest threads enabled for guest thread processing is in a wait state and, in accordance with the determining that the at least one of the plurality of guest threads enabled for guest thread processing is in the wait state, routes the I/O interruption to a guest thread enabled for guest thread processing and in the wait state.