Commit f0f37e22 authored by Sean Christopherson's avatar Sean Christopherson Committed by Paolo Bonzini
Browse files

KVM: x86/mmu: Refactor the per-slot level calculation in mapping_level() 



Invert the loop which adjusts the allowed page level based on what's
compatible with the associated memslot to use a largest-to-smallest
page size walk.  This paves the way for passing around a "max level"
variable instead of having redundant checks and/or multiple booleans.

No functional change intended.

Signed-off-by: default avatarSean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent cb9b88c6

arch/x86/kvm/mmu/mmu.c

+5 −5
Original line number Diff line number Diff line
@@ -1330,7 +1330,7 @@ gfn_to_memslot_dirty_bitmap(struct kvm_vcpu *vcpu, gfn_t gfn, 
static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn,

			 bool *force_pt_level)

{

	int host_level, level, max_level;

	int host_level, max_level;

	struct kvm_memory_slot *slot;



	if (unlikely(*force_pt_level))
@@ -1347,12 +1347,12 @@ static int mapping_level(struct kvm_vcpu *vcpu, gfn_t large_gfn, 
		return host_level;



	max_level = min(kvm_x86_ops->get_lpage_level(), host_level);



	for (level = PT_DIRECTORY_LEVEL; level <= max_level; ++level)

		if (__mmu_gfn_lpage_is_disallowed(large_gfn, level, slot))

	for ( ; max_level > PT_PAGE_TABLE_LEVEL; max_level--) {

		if (!__mmu_gfn_lpage_is_disallowed(large_gfn, max_level, slot))

			break;

	}



	return level - 1;

	return max_level;

}



/*