It's a bit confusing that page write protect handler is live in
mmio emulation handler. This moves it to stand alone gvt ops.
Also remove unnecessary check of write protected page access
in mmio read handler and cleanup handling of failsafe case.
v2: rebase
Reviewed-by: Xiong Zhang <xiong.y.zhang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This reverts commit b20d09886fd1b74cd2255d846029a049e524db14.
This caused windows driver boot errors for invalid page address.
Revert for now.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Refine previously broken PPGTT scratch. Scratch PTE was no correctly
handled and also the handling of scratch entries in page table walk was
not well organized, which brings gaps of introducing lazy shadow.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
As we want to re-use intel_vgpu_shadow_page in buidling scrach page table
and we don't want to put scrach page table page into hash table, a new
param is introduced to give the caller a choice to decide if a shadow page
should be put into hash table.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
As there is already an I915_GTT_PAGE_SIZE marco in i915, let GVT-g use it
as well. Also this patch re-names some GTT marcos with additional prefix.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
As the data structure of "intel_vgpu_guest_page" will become much heavier
in future, it's better to factor out the guest memory page track mechnisim
as early as possible.
Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
When doing the VGPU reset, we don't need to do the gtt/ppgtt reset.
This will make the GVT to do the ppgtt shadow every time for
a workload and caused really bad performance after a VGPU reset.
This patch will make sure ppgtt clean only happen at device module
level reset to fix this.
Signed-off-by: Chuanxiao Dong <chuanxiao.dong@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
When debugging the gtt code, found the intel_vgpu_gma_to_gpa() can
translate any given GMA though the GMA is not valid. This because
the GTT ops suppress the possible errors, which may result in an
invalid PT entry is retrieved by upper caller.
This patch changed the prototype of pte ops to propagate status to
callers. Then we make sure the GTT walker stop as early as when
a error is detected to prevent undefined behavior.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
This patch introduces a new function intel_vgpu_reset_gtt() to reset
the all GTT related status, including GGTT, PPGTT, scratch page. This
function can free all shadowed PPGTT, clear all GGTT entry, and clear
scratch page to all zero. After this, we can ensure no gtt related
information can be leakaged from one VM to anothor one when assign
vgpu instance across different VMs (not simultaneously).
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
The GGTT space is partitioned between vGPUs, it could be reused by
next vGPU after previous one is release, the stale entries need
point to scratch page when vGPU created.
v2: Reset logic move to vGPU create.
v3: Correct the commit msg.
v4: Move the reset function to vGPU init gtt function, as result it's no
need explicitly in vGPU reset logic as vGPU init gtt called during
reset.
Signed-off-by: Ping Gao <ping.a.gao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
All the unused entries in the page table tree(PML4E->PDPE->PDE->PTE)
should point to scratch page table/scratch page to avoid page walk error
due to the page prefetching.
When removing an entry in shadow PPGTT, it need map to scratch page
also, the older implementation use single scratch page to assign to all
level entries, it doesn't align the page walk behavior when removed
entry is in PML, PDP, PD. To avoid potential page walk error this patch
implement a scratch page tree to replace the single scratch page.
v2: more details in commit message address Kevin's comments.
Signed-off-by: Ping Gao <ping.a.gao@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
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: Zhi Wang <zhi.a.wang@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
