Invalidation of shared memory in a virtual environment

A computer program product for managing a shared memory mapping in a computer, wherein the computer program product comprises a computer readable storage medium having program instructions embodied thereon, and wherein the program instructions are executable by a processor to perform a method comprising:

• receiving, by the processor, a first shared page request, wherein the first shared page request is associated with a first logical page included in a first logical memory block (LMB) of a first logical partition (LPAR), wherein the first logical page corresponds to a physical page included in a shared memory region (SMR) associated with the first LPAR, wherein the physical page is included in a physical memory block of the computer, and wherein the first LPAR is included in a plurality of LPARs included in the computer;
• determining, by the processor, in response to the first shared page request, based at least in part on the first logical page corresponding to the physical page and the physical page included in the SMR, a shared access state associated with the first LMB, wherein the shared access state indicates that the SMR is associated with first LMB;
• receiving, by the processor, a second shared page request, wherein the second shared page request is associated with access to the physical page by a second LPAR included in the plurality of LPARs;
• determining, by the processor, in response to the second shared page request, a mapping state associated with the SMR, wherein the mapping state indicates that the second LPAR has established a mapping to the physical page;
• receiving, by the processor, a mapping request associated with the physical page;
• determining, by the processor, in response to the mapping request, based at least in part on the shared access state associated with the first LMB and the mapping state associated with the SMR, that the second LPAR has established a mapping to the physical page;
• and
• invalidating, by the processor, the second LPAR mapping to the physical page.

A system for managing a shared memory mapping in a computer having a plurality of logical partitions (LPARs), the system comprising:

• a first LPAR included in the plurality of LPARs;
• a shared memory region (SMR) associated with the first LPAR;
• a processor, wherein the processor is configured to execute a hypervisor program, and wherein the hypervisor program is configured to:
• receive a first shared page request, wherein the first shared page request is associated with a first logical page included in a first logical memory block (LMB) of the first LPAR, wherein the first logical page corresponds to a physical page included in a shared memory region (SMR) associated with the first LPAR, and wherein the physical page is included in a physical memory block of the computer;
• determine, in response to the first shared page request, based at least in part on the first logical page corresponding to the physical page and the physical page included in the SMR, a shared access state associated with the first LMB, wherein the shared access state indicates that the SMR is associated with first LMB;
• receive a second shared page request, wherein the second shared page request is associated with access to the physical page by a second LPAR included in the plurality of LPARs;
• determine, in response to the second shared page request, a mapping state associated with the SMR, wherein the mapping state indicates that the second LPAR has established a mapping to the physical page;
• receive a mapping request associated with the physical memory block;
• determine, in response to the mapping request, based at least in part on the shared access state associated with the first LMB and the mapping state associated with the SMR, that the second LPAR has established a mapping to the physical page;
• and
• invalidate the second LPAR mapping to the physical page.