Commit a13842dc authored by Xiao Guangrong's avatar Xiao Guangrong Committed by Paolo Bonzini
Browse files

KVM: MTRR: introduce var_mtrr_range 



It gets the range for the specified variable MTRR

Signed-off-by: default avatarXiao Guangrong <guangrong.xiao@linux.intel.com>
[Simplify boolean operations. - Paolo]
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent de9aef5e

arch/x86/kvm/mtrr.c

+17 −6
Original line number Diff line number Diff line
@@ -241,10 +241,25 @@ static int fixed_msr_to_range_index(u32 msr) 
	return fixed_mtrr_seg_unit_range_index(seg, unit);

}



static void var_mtrr_range(struct kvm_mtrr_range *range, u64 *start, u64 *end)

{

	u64 mask;



	*start = range->base & PAGE_MASK;



	mask = range->mask & PAGE_MASK;

	mask |= ~0ULL << boot_cpu_data.x86_phys_bits;



	/* This cannot overflow because writing to the reserved bits of

	 * variable MTRRs causes a #GP.

	 */

	*end = (*start | ~mask) + 1;

}



static void update_mtrr(struct kvm_vcpu *vcpu, u32 msr)

{

	struct kvm_mtrr *mtrr_state = &vcpu->arch.mtrr_state;

	gfn_t start, end, mask;

	gfn_t start, end;

	int index;



	if (msr == MSR_IA32_CR_PAT || !tdp_enabled ||
@@ -264,11 +279,7 @@ static void update_mtrr(struct kvm_vcpu *vcpu, u32 msr) 
	} else {

		/* variable range MTRRs. */

		index = (msr - 0x200) / 2;

		start = mtrr_state->var_ranges[index].base & PAGE_MASK;

		mask = mtrr_state->var_ranges[index].mask & PAGE_MASK;

		mask |= ~0ULL << cpuid_maxphyaddr(vcpu);



		end = ((start & mask) | ~mask) + 1;

		var_mtrr_range(&mtrr_state->var_ranges[index], &start, &end);

	}



	kvm_zap_gfn_range(vcpu->kvm, gpa_to_gfn(start), gpa_to_gfn(end));