Commit 1755fbcc authored by Avi Kivity's avatar Avi Kivity
Browse files

KVM: MMU: Introduce gfn_to_gpa() 



Converting a frame number to an address is tricky since the data type changes
size.  Introduce a function to do it.  This fixes an actual bug when
accessing guest ptes.

Signed-off-by: default avatarAvi Kivity <avi@qumranet.com>
parent 38c335f1

drivers/kvm/kvm.h

+4 −0
Original line number Diff line number Diff line
@@ -499,6 +499,10 @@ static inline int memslot_id(struct kvm *kvm, struct kvm_memory_slot *slot) 
	return slot - kvm->memslots;

}



static inline gpa_t gfn_to_gpa(gfn_t gfn)

{

	return (gpa_t)gfn << PAGE_SHIFT;

}



enum kvm_stat_kind {

	KVM_STAT_VM,

drivers/kvm/paging_tmpl.h

+2 −2
Original line number Diff line number Diff line
@@ -110,7 +110,7 @@ static int FNAME(walk_addr)(struct guest_walker *walker, 
		index = PT_INDEX(addr, walker->level);



		table_gfn = gpte_to_gfn(pte);

		pte_gpa = table_gfn << PAGE_SHIFT;

		pte_gpa = gfn_to_gpa(table_gfn);

		pte_gpa += index * sizeof(pt_element_t);

		walker->table_gfn[walker->level - 1] = table_gfn;

		pgprintk("%s: table_gfn[%d] %lx\n", __FUNCTION__,
@@ -442,7 +442,7 @@ static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr) 
	r = FNAME(walk_addr)(&walker, vcpu, vaddr, 0, 0, 0);



	if (r) {

		gpa = (gpa_t)walker.gfn << PAGE_SHIFT;

		gpa = gfn_to_gpa(walker.gfn);

		gpa |= vaddr & ~PAGE_MASK;

	}