Commit 407c61c6 authored by Xiao Guangrong's avatar Xiao Guangrong Committed by Avi Kivity
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KVM: MMU: abstract invalid guest pte mapping 



Introduce a common function to map invalid gpte

Signed-off-by: default avatarXiao Guangrong <xiaoguangrong@cn.fujitsu.com>
Signed-off-by: default avatarMarcelo Tosatti <mtosatti@redhat.com>
parent a4a8e6f7

arch/x86/kvm/mmu.c

+0 −3
Original line number Diff line number Diff line
@@ -3075,9 +3075,6 @@ static void mmu_pte_write_new_pte(struct kvm_vcpu *vcpu, 
		return;

        }



	if (is_rsvd_bits_set(&vcpu->arch.mmu, *(u64 *)new, PT_PAGE_TABLE_LEVEL))

		return;



	++vcpu->kvm->stat.mmu_pte_updated;

	if (!sp->role.cr4_pae)

		paging32_update_pte(vcpu, sp, spte, new);

arch/x86/kvm/paging_tmpl.h

+37 −34
Original line number Diff line number Diff line
@@ -299,25 +299,42 @@ static int FNAME(walk_addr_nested)(struct guest_walker *walker, 
					addr, access);

}



static bool FNAME(prefetch_invalid_gpte)(struct kvm_vcpu *vcpu,

				    struct kvm_mmu_page *sp, u64 *spte,

				    pt_element_t gpte)

{

	u64 nonpresent = shadow_trap_nonpresent_pte;



	if (is_rsvd_bits_set(&vcpu->arch.mmu, gpte, PT_PAGE_TABLE_LEVEL))

		goto no_present;



	if (!is_present_gpte(gpte)) {

		if (!sp->unsync)

			nonpresent = shadow_notrap_nonpresent_pte;

		goto no_present;

	}



	if (!(gpte & PT_ACCESSED_MASK))

		goto no_present;



	return false;



no_present:

	drop_spte(vcpu->kvm, spte, nonpresent);

	return true;

}



static void FNAME(update_pte)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp,

			      u64 *spte, const void *pte)

{

	pt_element_t gpte;

	unsigned pte_access;

	pfn_t pfn;

	u64 new_spte;



	gpte = *(const pt_element_t *)pte;

	if (~gpte & (PT_PRESENT_MASK | PT_ACCESSED_MASK)) {

		if (!is_present_gpte(gpte)) {

			if (sp->unsync)

				new_spte = shadow_trap_nonpresent_pte;

			else

				new_spte = shadow_notrap_nonpresent_pte;

			__set_spte(spte, new_spte);

		}

	if (FNAME(prefetch_invalid_gpte)(vcpu, sp, spte, gpte))

		return;

	}



	pgprintk("%s: gpte %llx spte %p\n", __func__, (u64)gpte, spte);

	pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte);

	if (gpte_to_gfn(gpte) != vcpu->arch.update_pte.gfn)
@@ -364,7 +381,6 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw, 
				u64 *sptep)

{

	struct kvm_mmu_page *sp;

	struct kvm_mmu *mmu = &vcpu->arch.mmu;

	pt_element_t *gptep = gw->prefetch_ptes;

	u64 *spte;

	int i;
@@ -395,16 +411,7 @@ static void FNAME(pte_prefetch)(struct kvm_vcpu *vcpu, struct guest_walker *gw, 


		gpte = gptep[i];



		if (is_rsvd_bits_set(mmu, gpte, PT_PAGE_TABLE_LEVEL))

			continue;



		if (!is_present_gpte(gpte)) {

			if (!sp->unsync)

				__set_spte(spte, shadow_notrap_nonpresent_pte);

			continue;

		}



		if (!(gpte & PT_ACCESSED_MASK))

		if (FNAME(prefetch_invalid_gpte)(vcpu, sp, spte, gpte))

			continue;



		pte_access = sp->role.access & FNAME(gpte_access)(vcpu, gpte);
@@ -761,7 +768,6 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) 
		pt_element_t gpte;

		gpa_t pte_gpa;

		gfn_t gfn;

		bool rsvd_bits_set;



		if (!is_shadow_present_pte(sp->spt[i]))

			continue;
@@ -773,18 +779,15 @@ static int FNAME(sync_page)(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) 
			return -EINVAL;



		gfn = gpte_to_gfn(gpte);

		rsvd_bits_set = is_rsvd_bits_set(&vcpu->arch.mmu, gpte,

						 PT_PAGE_TABLE_LEVEL);

		if (rsvd_bits_set || gfn != sp->gfns[i] ||

		      !is_present_gpte(gpte) || !(gpte & PT_ACCESSED_MASK)) {

			u64 nonpresent;



			if (rsvd_bits_set || is_present_gpte(gpte) ||

			      sp->unsync)

				nonpresent = shadow_trap_nonpresent_pte;

			else

				nonpresent = shadow_notrap_nonpresent_pte;

			drop_spte(vcpu->kvm, &sp->spt[i], nonpresent);



		if (FNAME(prefetch_invalid_gpte)(vcpu, sp, &sp->spt[i], gpte)) {

			kvm_flush_remote_tlbs(vcpu->kvm);

			continue;

		}



		if (gfn != sp->gfns[i]) {

			drop_spte(vcpu->kvm, &sp->spt[i],

				      shadow_trap_nonpresent_pte);

			kvm_flush_remote_tlbs(vcpu->kvm);

			continue;

		}