[Intel-gfx] [RFC 5/7] drm/i915/gvt: Introduce functions for retiring all shadow PPGTTs of a vGPU

[Zhi Wang]

Introduce a new function to retiring all shadow PPGTTs of a vGPU.

The shadow PPPGTs of a vGPU need to be invalidated if a guest modifies the
virtual private PPAT since the mapping between the virtual PPAT indexes
and the shadow PPAT indexes will be re-built after a guest writes a new
virtual PPAT configruation.

Signed-off-by: Zhi Wang <zhi.a.wang at intel.com>
---
 drivers/gpu/drm/i915/gvt/gtt.c | 23 +++++++++++++++++++++++
 drivers/gpu/drm/i915/gvt/gtt.h |  1 +
 2 files changed, 24 insertions(+)

diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
index 6e19d7a..1d7077d 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.c
+++ b/drivers/gpu/drm/i915/gvt/gtt.c
@@ -1745,6 +1745,11 @@ void intel_vgpu_unpin_mm(struct intel_vgpu_mm *mm)
 		return;
 
 	atomic_dec(&mm->pincount);
+
+	if (mm->need_rebuild) {
+		invalidate_mm(mm);
+		mm->need_rebuild = false;
+	}
 }
 
 /**
@@ -1798,6 +1803,24 @@ static int reclaim_one_mm(struct intel_gvt *gvt)
 	return 0;
 }
 
+static void retire_vgpu_ppgtt_mm(struct intel_vgpu *vgpu)
+{
+	struct intel_vgpu_mm *mm;
+	struct list_head *pos;
+
+	list_for_each(pos, &vgpu->gtt.mm_list_head) {
+		mm = container_of(pos, struct intel_vgpu_mm, list);
+
+		if (mm->type != INTEL_GVT_MM_PPGTT)
+			continue;
+		if (atomic_read(&mm->pincount)) {
+			mm->need_rebuild = true;
+			continue;
+		}
+		invalidate_mm(mm);
+	}
+}
+
 /*
  * GMA translation APIs.
  */
diff --git a/drivers/gpu/drm/i915/gvt/gtt.h b/drivers/gpu/drm/i915/gvt/gtt.h
index 6cd4fc7..a83d1f0 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.h
+++ b/drivers/gpu/drm/i915/gvt/gtt.h
@@ -147,6 +147,7 @@ struct intel_vgpu_mm {
 	int type;
 	bool initialized;
 	bool shadowed;
+	bool need_rebuild;
 
 	int page_table_entry_type;
 	u32 page_table_entry_size;
-- 
2.7.4