Commit 18c3640c authored by Paul Mackerras's avatar Paul Mackerras
Browse files

KVM: PPC: Book3S HV: Add infrastructure for running HPT guests on radix host 



This sets up the machinery for switching a guest between HPT (hashed
page table) and radix MMU modes, so that in future we can run a HPT
guest on a radix host on POWER9 machines.

* The KVM_PPC_CONFIGURE_V3_MMU ioctl can now specify either HPT or
  radix mode, on a radix host.

* The KVM_CAP_PPC_MMU_HASH_V3 capability now returns 1 on POWER9
  with HV KVM on a radix host.

* The KVM_PPC_GET_SMMU_INFO returns information about the HPT MMU on a
  radix host.

* The KVM_PPC_ALLOCATE_HTAB ioctl on a radix host will switch the
  guest to HPT mode and allocate a HPT.

* For simplicity, we now allocate the rmap array for each memslot,
  even on a radix host, since it will be needed if the guest switches
  to HPT mode.

* Since we cannot yet run a HPT guest on a radix host, the KVM_RUN
  ioctl will return an EINVAL error in that case.

Signed-off-by: default avatarPaul Mackerras <paulus@ozlabs.org>
parent e641a317

arch/powerpc/include/asm/kvm_ppc.h

+3 −0
Original line number Diff line number Diff line
@@ -168,6 +168,7 @@ extern int kvmppc_allocate_hpt(struct kvm_hpt_info *info, u32 order); 
extern void kvmppc_set_hpt(struct kvm *kvm, struct kvm_hpt_info *info);

extern long kvmppc_alloc_reset_hpt(struct kvm *kvm, int order);

extern void kvmppc_free_hpt(struct kvm_hpt_info *info);

extern void kvmppc_rmap_reset(struct kvm *kvm);

extern long kvmppc_prepare_vrma(struct kvm *kvm,

				struct kvm_userspace_memory_region *mem);

extern void kvmppc_map_vrma(struct kvm_vcpu *vcpu,
@@ -177,6 +178,8 @@ extern long kvm_spapr_tce_attach_iommu_group(struct kvm *kvm, int tablefd, 
		struct iommu_group *grp);

extern void kvm_spapr_tce_release_iommu_group(struct kvm *kvm,

		struct iommu_group *grp);

extern int kvmppc_switch_mmu_to_hpt(struct kvm *kvm);

extern int kvmppc_switch_mmu_to_radix(struct kvm *kvm);



extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,

				struct kvm_create_spapr_tce_64 *args);

arch/powerpc/kvm/book3s_64_mmu_hv.c

+12 −10
Original line number Diff line number Diff line
@@ -73,8 +73,6 @@ struct kvm_resize_hpt { 
	struct kvm_hpt_info hpt;

};



static void kvmppc_rmap_reset(struct kvm *kvm);



int kvmppc_allocate_hpt(struct kvm_hpt_info *info, u32 order)

{

	unsigned long hpt = 0;
@@ -136,9 +134,6 @@ long kvmppc_alloc_reset_hpt(struct kvm *kvm, int order) 
	long err = -EBUSY;

	struct kvm_hpt_info info;



	if (kvm_is_radix(kvm))

		return -EINVAL;



	mutex_lock(&kvm->lock);

	if (kvm->arch.mmu_ready) {

		kvm->arch.mmu_ready = 0;
@@ -149,6 +144,12 @@ long kvmppc_alloc_reset_hpt(struct kvm *kvm, int order) 
			goto out;

		}

	}

	if (kvm_is_radix(kvm)) {

		err = kvmppc_switch_mmu_to_hpt(kvm);

		if (err)

			goto out;

	}



	if (kvm->arch.hpt.order == order) {

		/* We already have a suitable HPT */
@@ -182,6 +183,7 @@ out: 
void kvmppc_free_hpt(struct kvm_hpt_info *info)

{

	vfree(info->rev);

	info->rev = NULL;

	if (info->cma)

		kvm_free_hpt_cma(virt_to_page(info->virt),

				 1 << (info->order - PAGE_SHIFT));
@@ -349,6 +351,9 @@ static int kvmppc_mmu_book3s_64_hv_xlate(struct kvm_vcpu *vcpu, gva_t eaddr, 
	int index;

	int virtmode = vcpu->arch.shregs.msr & (data ? MSR_DR : MSR_IR);



	if (kvm_is_radix(vcpu->kvm))

		return kvmppc_mmu_radix_xlate(vcpu, eaddr, gpte, data, iswrite);



	/* Get SLB entry */

	if (virtmode) {

		slbe = kvmppc_mmu_book3s_hv_find_slbe(vcpu, eaddr);
@@ -710,7 +715,7 @@ int kvmppc_book3s_hv_page_fault(struct kvm_run *run, struct kvm_vcpu *vcpu, 
	goto out_put;

}



static void kvmppc_rmap_reset(struct kvm *kvm)

void kvmppc_rmap_reset(struct kvm *kvm)

{

	struct kvm_memslots *slots;

	struct kvm_memory_slot *memslot;
@@ -2089,9 +2094,6 @@ void kvmppc_mmu_book3s_hv_init(struct kvm_vcpu *vcpu) 


	vcpu->arch.slb_nr = 32;		/* POWER7/POWER8 */



	if (kvm_is_radix(vcpu->kvm))

		mmu->xlate = kvmppc_mmu_radix_xlate;

	else

	mmu->xlate = kvmppc_mmu_book3s_64_hv_xlate;

	mmu->reset_msr = kvmppc_mmu_book3s_64_hv_reset_msr;

arch/powerpc/kvm/book3s_64_mmu_radix.c

+1 −0
Original line number Diff line number Diff line
@@ -662,6 +662,7 @@ void kvmppc_free_radix(struct kvm *kvm) 
		pgd_clear(pgd);

	}

	pgd_free(kvm->mm, kvm->arch.pgtable);

	kvm->arch.pgtable = NULL;

}



static void pte_ctor(void *addr)

arch/powerpc/kvm/book3s_hv.c

+62 −25
Original line number Diff line number Diff line
@@ -2442,6 +2442,9 @@ static void prepare_threads(struct kvmppc_vcore *vc) 
	for_each_runnable_thread(i, vcpu, vc) {

		if (signal_pending(vcpu->arch.run_task))

			vcpu->arch.ret = -EINTR;

		else if (kvm_is_radix(vc->kvm) != radix_enabled())

			/* can't actually run HPT guest on radix host yet... */

			vcpu->arch.ret = -EINVAL;

		else if (vcpu->arch.vpa.update_pending ||

			 vcpu->arch.slb_shadow.update_pending ||

			 vcpu->arch.dtl.update_pending)
@@ -3338,13 +3341,6 @@ static int kvm_vm_ioctl_get_smmu_info_hv(struct kvm *kvm, 
{

	struct kvm_ppc_one_seg_page_size *sps;



	/*

	 * Since we don't yet support HPT guests on a radix host,

	 * return an error if the host uses radix.

	 */

	if (radix_enabled())

		return -EINVAL;



	/*

	 * POWER7, POWER8 and POWER9 all support 32 storage keys for data.

	 * POWER7 doesn't support keys for instruction accesses,
@@ -3447,15 +3443,6 @@ static void kvmppc_core_free_memslot_hv(struct kvm_memory_slot *free, 
static int kvmppc_core_create_memslot_hv(struct kvm_memory_slot *slot,

					 unsigned long npages)

{

	/*

	 * For now, if radix_enabled() then we only support radix guests,

	 * and in that case we don't need the rmap array.

	 */

	if (radix_enabled()) {

		slot->arch.rmap = NULL;

		return 0;

	}



	slot->arch.rmap = vzalloc(npages * sizeof(*slot->arch.rmap));

	if (!slot->arch.rmap)

		return -ENOMEM;
@@ -3628,6 +3615,34 @@ static int kvmppc_hv_setup_htab_rma(struct kvm_vcpu *vcpu) 
	goto out_srcu;

}



/* Must be called with kvm->lock held and mmu_ready = 0 and no vcpus running */

int kvmppc_switch_mmu_to_hpt(struct kvm *kvm)

{

	kvmppc_free_radix(kvm);

	kvmppc_update_lpcr(kvm, LPCR_VPM1,

			   LPCR_VPM1 | LPCR_UPRT | LPCR_GTSE | LPCR_HR);

	kvmppc_rmap_reset(kvm);

	kvm->arch.radix = 0;

	kvm->arch.process_table = 0;

	return 0;

}



/* Must be called with kvm->lock held and mmu_ready = 0 and no vcpus running */

int kvmppc_switch_mmu_to_radix(struct kvm *kvm)

{

	int err;



	err = kvmppc_init_vm_radix(kvm);

	if (err)

		return err;



	kvmppc_free_hpt(&kvm->arch.hpt);

	kvmppc_update_lpcr(kvm, LPCR_UPRT | LPCR_GTSE | LPCR_HR,

			   LPCR_VPM1 | LPCR_UPRT | LPCR_GTSE | LPCR_HR);

	kvm->arch.radix = 1;

	return 0;

}



#ifdef CONFIG_KVM_XICS

/*

 * Allocate a per-core structure for managing state about which cores are
@@ -3771,7 +3786,7 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm) 
	}



	/*

	 * For now, if the host uses radix, the guest must be radix.

	 * If the host uses radix, the guest starts out as radix.

	 */

	if (radix_enabled()) {

		kvm->arch.radix = 1;
@@ -3795,7 +3810,7 @@ static int kvmppc_core_init_vm_hv(struct kvm *kvm) 
	 * Work out how many sets the TLB has, for the use of

	 * the TLB invalidation loop in book3s_hv_rmhandlers.S.

	 */

	if (kvm_is_radix(kvm))

	if (radix_enabled())

		kvm->arch.tlb_sets = POWER9_TLB_SETS_RADIX;	/* 128 */

	else if (cpu_has_feature(CPU_FTR_ARCH_300))

		kvm->arch.tlb_sets = POWER9_TLB_SETS_HASH;	/* 256 */
@@ -4185,6 +4200,7 @@ static int kvmhv_configure_mmu(struct kvm *kvm, struct kvm_ppc_mmuv3_cfg *cfg) 
{

	unsigned long lpcr;

	int radix;

	int err;



	/* If not on a POWER9, reject it */

	if (!cpu_has_feature(CPU_FTR_ARCH_300))
@@ -4194,12 +4210,8 @@ static int kvmhv_configure_mmu(struct kvm *kvm, struct kvm_ppc_mmuv3_cfg *cfg) 
	if (cfg->flags & ~(KVM_PPC_MMUV3_RADIX | KVM_PPC_MMUV3_GTSE))

		return -EINVAL;



	/* We can't change a guest to/from radix yet */

	radix = !!(cfg->flags & KVM_PPC_MMUV3_RADIX);

	if (radix != kvm_is_radix(kvm))

		return -EINVAL;



	/* GR (guest radix) bit in process_table field must match */

	radix = !!(cfg->flags & KVM_PPC_MMUV3_RADIX);

	if (!!(cfg->process_table & PATB_GR) != radix)

		return -EINVAL;
@@ -4207,15 +4219,40 @@ static int kvmhv_configure_mmu(struct kvm *kvm, struct kvm_ppc_mmuv3_cfg *cfg) 
	if ((cfg->process_table & PRTS_MASK) > 24)

		return -EINVAL;



	/* We can change a guest to/from radix now, if the host is radix */

	if (radix && !radix_enabled())

		return -EINVAL;



	mutex_lock(&kvm->lock);

	if (radix != kvm_is_radix(kvm)) {

		if (kvm->arch.mmu_ready) {

			kvm->arch.mmu_ready = 0;

			/* order mmu_ready vs. vcpus_running */

			smp_mb();

			if (atomic_read(&kvm->arch.vcpus_running)) {

				kvm->arch.mmu_ready = 1;

				err = -EBUSY;

				goto out_unlock;

			}

		}

		if (radix)

			err = kvmppc_switch_mmu_to_radix(kvm);

		else

			err = kvmppc_switch_mmu_to_hpt(kvm);

		if (err)

			goto out_unlock;

	}



	kvm->arch.process_table = cfg->process_table;

	kvmppc_setup_partition_table(kvm);



	lpcr = (cfg->flags & KVM_PPC_MMUV3_GTSE) ? LPCR_GTSE : 0;

	kvmppc_update_lpcr(kvm, lpcr, LPCR_GTSE);

	mutex_unlock(&kvm->lock);

	err = 0;



	return 0;

 out_unlock:

	mutex_unlock(&kvm->lock);

	return err;

}



static struct kvmppc_ops kvm_ops_hv = {

arch/powerpc/kvm/powerpc.c

+1 −2
Original line number Diff line number Diff line
@@ -590,8 +590,7 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) 
		r = !!(hv_enabled && radix_enabled());

		break;

	case KVM_CAP_PPC_MMU_HASH_V3:

		r = !!(hv_enabled && !radix_enabled() &&

		       cpu_has_feature(CPU_FTR_ARCH_300));

		r = !!(hv_enabled && cpu_has_feature(CPU_FTR_ARCH_300));

		break;

#endif

	case KVM_CAP_SYNC_MMU:

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