• Zhi Wang's avatar
    drm/i915/gvt: vGPU graphics memory virtualization · 2707e444
    Zhi Wang authored
    The vGPU graphics memory emulation framework is responsible for graphics
    memory table virtualization. Under virtualization environment, a VM will
    populate the page table entry with guest page frame number(GPFN/GFN), while
    HW needs a page table filled with MFN(Machine frame number). The
    relationship between GFN and MFN(Machine frame number) is managed by
    hypervisor, while GEN HW doesn't have such knowledge to translate a GFN.
    To solve this gap, shadow GGTT/PPGTT page table is introdcued.
    For GGTT, the GFN inside the guest GGTT page table entry will be translated
    into MFN and written into physical GTT MMIO registers when guest write
    virtual GTT MMIO registers.
    For PPGTT, a shadow PPGTT page table will be created and write-protected
    translated from guest PPGTT page table.  And the shadow page table root
    pointers will be written into the shadow context after a guest workload
    is shadowed.
    vGPU graphics memory emulation framework consists:
    - Per-GEN HW platform page table entry bits extract/de-extract routines.
    - GTT MMIO register emulation handlers, which will call hypercall to do
    GFN->MFN translation when guest write GTT MMIO register
    - PPGTT shadow page table routines, e.g. shadow create/destroy/out-of-sync
    Signed-off-by: default avatarZhi Wang <zhi.a.wang@intel.com>
    Signed-off-by: default avatarZhenyu Wang <zhenyuw@linux.intel.com>
Makefile 243 Bytes