Provide the basics for architectures to implement a fast-only version of
kvm_{test_,}age_gfn.

Signed-off-by: James Houghton <jthoughton@google.com>
---
 include/linux/kvm_host.h | 1 +
 virt/kvm/kvm_main.c      | 2 ++
 2 files changed, 3 insertions(+)

diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 98a987e88578..55861db556e2 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -258,6 +258,7 @@ int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu);
 #ifdef CONFIG_KVM_GENERIC_MMU_NOTIFIER
 union kvm_mmu_notifier_arg {
 	unsigned long attributes;
+	bool fast_only;
 };
 
 struct kvm_gfn_range {
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index ec07caaed6b6..8630dfc82d61 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -867,6 +867,7 @@ static int kvm_mmu_notifier_clear_young(struct mmu_notifier *mn,
 		.may_block	= false,
 		.lockless	=
 			IS_ENABLED(CONFIG_KVM_MMU_NOTIFIER_YOUNG_LOCKLESS),
+		.arg.fast_only		= fast_only,
 	};
 
 	trace_kvm_age_hva(start, end, fast_only);
@@ -902,6 +903,7 @@ static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
 		.may_block	= false,
 		.lockless	=
 			IS_ENABLED(CONFIG_KVM_MMU_NOTIFIER_YOUNG_LOCKLESS),
+		.arg.fast_only		= fast_only,
 	};
 
 	trace_kvm_test_age_hva(address, fast_only);
-- 
2.46.0.792.g87dc391469-goog