drm/i915/gvt: Introduce ops->set_present()

We need ops->set_present() during generating a new scratch page table
entry.

Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
index 74be5e6..3d6008b 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.c
+++ b/drivers/gpu/drm/i915/gvt/gtt.c
@@ -397,6 +397,11 @@ static void gtt_entry_clear_present(struct intel_gvt_gtt_entry *e)
 	e->val64 &= ~BIT(0);
 }
 
+static void gtt_entry_set_present(struct intel_gvt_gtt_entry *e)
+{
+	e->val64 |= BIT(0);
+}
+
 /*
  * Per-platform GMA routines.
  */
@@ -426,6 +431,7 @@ static struct intel_gvt_gtt_pte_ops gen8_gtt_pte_ops = {
 	.get_entry = gtt_get_entry64,
 	.set_entry = gtt_set_entry64,
 	.clear_present = gtt_entry_clear_present,
+	.set_present = gtt_entry_set_present,
 	.test_present = gen8_gtt_test_present,
 	.test_pse = gen8_gtt_test_pse,
 	.get_pfn = gen8_gtt_get_pfn,
diff --git a/drivers/gpu/drm/i915/gvt/gtt.h b/drivers/gpu/drm/i915/gvt/gtt.h
index ab59027..f98c1c1 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.h
+++ b/drivers/gpu/drm/i915/gvt/gtt.h
@@ -62,6 +62,7 @@ struct intel_gvt_gtt_pte_ops {
 			 struct intel_vgpu *vgpu);
 	bool (*test_present)(struct intel_gvt_gtt_entry *e);
 	void (*clear_present)(struct intel_gvt_gtt_entry *e);
+	void (*set_present)(struct intel_gvt_gtt_entry *e);
 	bool (*test_pse)(struct intel_gvt_gtt_entry *e);
 	void (*set_pfn)(struct intel_gvt_gtt_entry *e, unsigned long pfn);
 	unsigned long (*get_pfn)(struct intel_gvt_gtt_entry *e);