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: Paul Mackerras <paulus@xxxxxxxxxx>
---
arch/powerpc/include/asm/kvm_ppc.h | 3 ++
arch/powerpc/kvm/book3s_64_mmu_hv.c | 22 +++++----
arch/powerpc/kvm/book3s_64_mmu_radix.c | 1 +
arch/powerpc/kvm/book3s_hv.c | 87 ++++++++++++++++++++++++----------
arch/powerpc/kvm/powerpc.c | 3 +-
5 files changed, 79 insertions(+), 37 deletions(-)
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index ba5fadd..96753f3 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -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);
diff --git a/arch/powerpc/kvm/book3s_64_mmu_hv.c b/arch/powerpc/kvm/book3s_64_mmu_hv.c
index 944f7a5..6aec8a2 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_hv.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_hv.c
@@ -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 @@ long kvmppc_alloc_reset_hpt(struct kvm *kvm, int order)
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;
@@ -2089,10 +2094,7 @@ 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->xlate = kvmppc_mmu_book3s_64_hv_xlate;
mmu->reset_msr = kvmppc_mmu_book3s_64_hv_reset_msr;
vcpu->arch.hflags |= BOOK3S_HFLAG_SLB;
diff --git a/arch/powerpc/kvm/book3s_64_mmu_radix.c b/arch/powerpc/kvm/book3s_64_mmu_radix.c
index 6336b13..58618f6 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_radix.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_radix.c
@@ -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)
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 96b92d4..040e102 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -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)
@@ -3339,13 +3342,6 @@ 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,
* POWER8 and POWER9 do.
@@ -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 = {
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index a3746b9..a0b7f09 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -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:
--
2.7.4
