Commit fb43496c authored by Ben Gardon's avatar Ben Gardon Committed by Paolo Bonzini
Browse files

KVM: x86/MMU: Simplify flow of vmx_get_mt_mask 



Remove the gotos from vmx_get_mt_mask.  It's easier to build the whole
memory type at once, than it is to combine separate cacheability and
ipat fields.

No functional change intended.

Signed-off-by: default avatarBen Gardon <bgardon@google.com>
Message-Id: <20211115234603.2908381-12-bgardon@google.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 8283e36a

arch/x86/kvm/vmx/vmx.c

+7 −16
Original line number Diff line number Diff line
@@ -6947,7 +6947,6 @@ static int __init vmx_check_processor_compat(void) 
static u64 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio)

{

	u8 cache;

	u64 ipat = 0;



	/* We wanted to honor guest CD/MTRR/PAT, but doing so could result in

	 * memory aliases with conflicting memory types and sometimes MCEs.
@@ -6967,30 +6966,22 @@ static u64 vmx_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) 
	 * EPT memory type is used to emulate guest CD/MTRR.

	 */



	if (is_mmio) {

		cache = MTRR_TYPE_UNCACHABLE;

		goto exit;

	}

	if (is_mmio)

		return MTRR_TYPE_UNCACHABLE << VMX_EPT_MT_EPTE_SHIFT;



	if (!kvm_arch_has_noncoherent_dma(vcpu->kvm)) {

		ipat = VMX_EPT_IPAT_BIT;

		cache = MTRR_TYPE_WRBACK;

		goto exit;

	}

	if (!kvm_arch_has_noncoherent_dma(vcpu->kvm))

		return (MTRR_TYPE_WRBACK << VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IPAT_BIT;



	if (kvm_read_cr0(vcpu) & X86_CR0_CD) {

		ipat = VMX_EPT_IPAT_BIT;

		if (kvm_check_has_quirk(vcpu->kvm, KVM_X86_QUIRK_CD_NW_CLEARED))

			cache = MTRR_TYPE_WRBACK;

		else

			cache = MTRR_TYPE_UNCACHABLE;

		goto exit;

	}



	cache = kvm_mtrr_get_guest_memory_type(vcpu, gfn);

		return (cache << VMX_EPT_MT_EPTE_SHIFT) | VMX_EPT_IPAT_BIT;

	}



exit:

	return (cache << VMX_EPT_MT_EPTE_SHIFT) | ipat;

	return kvm_mtrr_get_guest_memory_type(vcpu, gfn) << VMX_EPT_MT_EPTE_SHIFT;

}



static void vmcs_set_secondary_exec_control(struct vcpu_vmx *vmx, u32 new_ctl)