• David Gibson's avatar
    KVM: PPC: Book3S HV: HPT resizing documentation and reserved numbers · ef1ead0c
    David Gibson authored
    This adds a new powerpc-specific KVM_CAP_SPAPR_RESIZE_HPT capability to
    advertise whether KVM is capable of handling the PAPR extensions for
    resizing the hashed page table during guest runtime.  It also adds
    definitions for two new VM ioctl()s to implement this extension, and
    documentation of the same.
    
    Note that, HPT resizing is already possible with KVM PR without kernel
    modification, since the HPT is managed within userspace (qemu).  The
    capability defined here will only be set where an in-kernel implementation
    of resizing is necessary, i.e. for KVM HV.  To determine if the userspace
    resize implementation can be used, it's necessary to check
    KVM_CAP_PPC_ALLOC_HTAB.  Unfortunately older kernels incorrectly set
    KVM_CAP_PPC_ALLOC_HTAB even with KVM PR.  If userspace it want to support
    resizing with KVM PR on such kernels, it will need a workaround.
    Signed-off-by: default avatarDavid Gibson <david@gibson.dropbear.id.au>
    Signed-off-by: default avatarPaul Mackerras <paulus@ozlabs.org>
    ef1ead0c
api.txt 133 KB