From: Sean Christopherson Date: Fri, 6 Dec 2019 23:57:19 +0000 (-0800) Subject: KVM: x86/mmu: Refactor the per-slot level calculation in mapping_level() X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=f0f37e229c0517fa0d8bda73a2aeee28260370a2;p=openwrt%2Fstaging%2Fblogic.git 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: Sean Christopherson Signed-off-by: Paolo Bonzini --- diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index defe94ecd0a4..8db2bb050809 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -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; } /*