KVM: MTRR: introduce var_mtrr_range

It gets the range for the specified variable MTRR

Signed-off-by: Xiao Guangrong <guangrong.xiao@linux.intel.com>
[Simplify boolean operations. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Xiao Guangrong 2015-06-15 16:55:30 +08:00 committed by Paolo Bonzini
parent de9aef5e1a
commit a13842dc66

View File

@ -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));