Virtualization intermediary/virtual machine guest operating system collaborative scsi path management

A method of direct access by a virtual machine (VM) running on a host machine to physical storage via a virtual function (VF) running on an input/output (IO) adapter comprising:

• identifying by a virtualization intermediary running on the host machine a change in an active path associated with a virtual storage device allocated to the VM;
• storing by the virtualization intermediary an indication of the changed active path to a memory region shared by a guest driver of the VM and by the virtualization intermediary;
• sending by the virtualization intermediary a notification to the guest driver of the change in active path associated with the virtual storage device;
• and
• obtaining by the guest driver the stored indication of the active path from the shared memory region.

An article of manufacture including a machine readable storage device encoded with computer readable instructions to cause a machine to perform a process to direct access by a virtual machine (VM) running on a host machine to physical storage via a virtual function (VF) running on an input/output (IO) adapter, the process comprising:

• storing by a virtualization intermediary an indication of an active path associated with a virtual storage device to a memory region shared by the guest driver and the virtualization intermediary;
• obtaining by the guest driver the stored indication of the active path from the shared memory region;
• dispatching an IO request by the guest driver to the VF that includes an indication of the active path;
• and
• sending by the VF an IO request that includes the indicated active path.

An article of manufacture including a machine readable storage device encoded with computer readable instructions to cause a machine to perform a process to direct access by a virtual machine (VM) running on a host machine to physical storage via a virtual function (VF) running on an input/output (IO) adapter, the process comprising:

• identifying by a virtualization intermediary running on the host machine a change in an active path associated with a virtual storage device allocated to the VM;
• storing by the virtualization intermediary an indication of the changed active path to a memory region shared by a guest driver of the VM and by the virtualization intermediary;
• sending by the virtualization intermediary a notification to the guest driver of the change in active path associated with the virtual storage device;
• and
• obtaining by the guest driver the stored indication of the active path from the shared memory region.