• Paul Brook's avatar
    Large page TLB flush · d4c430a8
    Paul Brook authored
    QEMU uses a fixed page size for the CPU TLB.  If the guest uses large
    pages then we effectively split these into multiple smaller pages, and
    populate the corresponding TLB entries on demand.
    When the guest invalidates the TLB by virtual address we must invalidate
    all entries covered by the large page.  However the address used to
    invalidate the entry may not be present in the QEMU TLB, so we do not
    know which regions to clear.
    Implementing a full vaiable size TLB is hard and slow, so just keep a
    simple address/mask pair to record which addresses may have been mapped by
    large pages.  If the guest invalidates this region then flush the
    whole TLB.
    Signed-off-by: default avatarPaul Brook <paul@codesourcery.com>
helper.c 9.47 KB