[PATCH v2 06/27] drm/i915/gvt: Put the page reference obtained by KVM's gfn_to_pfn()

[Sean Christopherson]

Put the struct page reference acquired by gfn_to_pfn(), KVM's API is that
the caller is ultimately responsible for dropping any reference.

Note, kvm_release_pfn_clean() ensures the pfn is actually a refcounted
struct page before trying to put any references.

Fixes: b901b252b6cf ("drm/i915/gvt: Add 2M huge gtt support")
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
 drivers/gpu/drm/i915/gvt/gtt.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
index d59c7ab9d224..15848b041a0d 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.c
+++ b/drivers/gpu/drm/i915/gvt/gtt.c
@@ -1160,6 +1160,7 @@ static int is_2MB_gtt_possible(struct intel_vgpu *vgpu,
 	unsigned long gfn = ops->get_pfn(entry);
 	kvm_pfn_t pfn;
 	int max_level;
+	int ret;
 
 	if (!HAS_PAGE_SIZES(vgpu->gvt->gt->i915, I915_GTT_PAGE_SIZE_2M))
 		return 0;
@@ -1179,7 +1180,9 @@ static int is_2MB_gtt_possible(struct intel_vgpu *vgpu,
 	if (!pfn_valid(pfn))
 		return -EINVAL;
 
-	return PageTransHuge(pfn_to_page(pfn));
+	ret = PageTransHuge(pfn_to_page(pfn));
+	kvm_release_pfn_clean(pfn);
+	return ret;
 }
 
 static int split_2MB_gtt_entry(struct intel_vgpu *vgpu,
-- 
2.40.0.rc1.284.g88254d51c5-goog