KVM: PPC: E500: Split host and guest MMU parts

This patch splits the file e500_tlb.c into e500_mmu.c (guest TLB handling)
and e500_mmu_host.c (host TLB handling).

The main benefit of this split is readability and maintainability. It's
just a lot harder to write dirty code :).

Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 672 insertions, 0 deletions

diff --git a/arch/powerpc/kvm/e500_mmu_host.c b/arch/powerpc/kvm/e500_mmu_host.c
new file mode 100644
index 000000000000..4c32d6510133
--- /dev/null
+++ b/arch/powerpc/kvm/e500_mmu_host.c
@@ -0,0 +1,672 @@
+/*
+ * Copyright (C) 2008-2013 Freescale Semiconductor, Inc. All rights reserved.
+ *
+ * Author: Yu Liu, yu.liu@freescale.com
+ *         Scott Wood, scottwood@freescale.com
+ *         Ashish Kalra, ashish.kalra@freescale.com
+ *         Varun Sethi, varun.sethi@freescale.com
+ *         Alexander Graf, agraf@suse.de
+ *
+ * Description:
+ * This file is based on arch/powerpc/kvm/44x_tlb.c,
+ * by Hollis Blanchard <hollisb@us.ibm.com>.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, version 2, as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/kvm.h>
+#include <linux/kvm_host.h>
+#include <linux/highmem.h>
+#include <linux/log2.h>
+#include <linux/uaccess.h>
+#include <linux/sched.h>
+#include <linux/rwsem.h>
+#include <linux/vmalloc.h>
+#include <linux/hugetlb.h>
+#include <asm/kvm_ppc.h>
+
+#include "e500.h"
+#include "trace.h"
+#include "timing.h"
+#include "e500_mmu_host.h"
+
+#define to_htlb1_esel(esel) (host_tlb_params[1].entries - (esel) - 1)
+
+static struct kvmppc_e500_tlb_params host_tlb_params[E500_TLB_NUM];
+
+static inline unsigned int tlb1_max_shadow_size(void)
+{
+	/* reserve one entry for magic page */
+	return host_tlb_params[1].entries - tlbcam_index - 1;
+}
+
+static inline u32 e500_shadow_mas3_attrib(u32 mas3, int usermode)
+{
+	/* Mask off reserved bits. */
+	mas3 &= MAS3_ATTRIB_MASK;
+
+#ifndef CONFIG_KVM_BOOKE_HV
+	if (!usermode) {
+		/* Guest is in supervisor mode,
+		 * so we need to translate guest
+		 * supervisor permissions into user permissions. */
+		mas3 &= ~E500_TLB_USER_PERM_MASK;
+		mas3 |= (mas3 & E500_TLB_SUPER_PERM_MASK) << 1;
+	}
+	mas3 |= E500_TLB_SUPER_PERM_MASK;
+#endif
+	return mas3;
+}
+
+static inline u32 e500_shadow_mas2_attrib(u32 mas2, int usermode)
+{
+#ifdef CONFIG_SMP
+	return (mas2 & MAS2_ATTRIB_MASK) | MAS2_M;
+#else
+	return mas2 & MAS2_ATTRIB_MASK;
+#endif
+}
+
+/*
+ * writing shadow tlb entry to host TLB
+ */
+static inline void __write_host_tlbe(struct kvm_book3e_206_tlb_entry *stlbe,
+				     uint32_t mas0)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	mtspr(SPRN_MAS0, mas0);
+	mtspr(SPRN_MAS1, stlbe->mas1);
+	mtspr(SPRN_MAS2, (unsigned long)stlbe->mas2);
+	mtspr(SPRN_MAS3, (u32)stlbe->mas7_3);
+	mtspr(SPRN_MAS7, (u32)(stlbe->mas7_3 >> 32));
+#ifdef CONFIG_KVM_BOOKE_HV
+	mtspr(SPRN_MAS8, stlbe->mas8);
+#endif
+	asm volatile("isync; tlbwe" : : : "memory");
+
+#ifdef CONFIG_KVM_BOOKE_HV
+	/* Must clear mas8 for other host tlbwe's */
+	mtspr(SPRN_MAS8, 0);
+	isync();
+#endif
+	local_irq_restore(flags);
+
+	trace_kvm_booke206_stlb_write(mas0, stlbe->mas8, stlbe->mas1,
+	                              stlbe->mas2, stlbe->mas7_3);
+}
+
+/*
+ * Acquire a mas0 with victim hint, as if we just took a TLB miss.
+ *
+ * We don't care about the address we're searching for, other than that it's
+ * in the right set and is not present in the TLB.  Using a zero PID and a
+ * userspace address means we don't have to set and then restore MAS5, or
+ * calculate a proper MAS6 value.
+ */
+static u32 get_host_mas0(unsigned long eaddr)
+{
+	unsigned long flags;
+	u32 mas0;
+
+	local_irq_save(flags);
+	mtspr(SPRN_MAS6, 0);
+	asm volatile("tlbsx 0, %0" : : "b" (eaddr & ~CONFIG_PAGE_OFFSET));
+	mas0 = mfspr(SPRN_MAS0);
+	local_irq_restore(flags);
+
+	return mas0;
+}
+
+/* sesel is for tlb1 only */
+static inline void write_host_tlbe(struct kvmppc_vcpu_e500 *vcpu_e500,
+		int tlbsel, int sesel, struct kvm_book3e_206_tlb_entry *stlbe)
+{
+	u32 mas0;
+
+	if (tlbsel == 0) {
+		mas0 = get_host_mas0(stlbe->mas2);
+		__write_host_tlbe(stlbe, mas0);
+	} else {
+		__write_host_tlbe(stlbe,
+				  MAS0_TLBSEL(1) |
+				  MAS0_ESEL(to_htlb1_esel(sesel)));
+	}
+}
+
+/* sesel is for tlb1 only */
+static void write_stlbe(struct kvmppc_vcpu_e500 *vcpu_e500,
+			struct kvm_book3e_206_tlb_entry *gtlbe,
+			struct kvm_book3e_206_tlb_entry *stlbe,
+			int stlbsel, int sesel)
+{
+	int stid;
+
+	preempt_disable();
+	stid = kvmppc_e500_get_tlb_stid(&vcpu_e500->vcpu, gtlbe);
+
+	stlbe->mas1 |= MAS1_TID(stid);
+	write_host_tlbe(vcpu_e500, stlbsel, sesel, stlbe);
+	preempt_enable();
+}
+
+#ifdef CONFIG_KVM_E500V2
+/* XXX should be a hook in the gva2hpa translation */
+void kvmppc_map_magic(struct kvm_vcpu *vcpu)
+{
+	struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
+	struct kvm_book3e_206_tlb_entry magic;
+	ulong shared_page = ((ulong)vcpu->arch.shared) & PAGE_MASK;
+	unsigned int stid;
+	pfn_t pfn;
+
+	pfn = (pfn_t)virt_to_phys((void *)shared_page) >> PAGE_SHIFT;
+	get_page(pfn_to_page(pfn));
+
+	preempt_disable();
+	stid = kvmppc_e500_get_sid(vcpu_e500, 0, 0, 0, 0);
+
+	magic.mas1 = MAS1_VALID | MAS1_TS | MAS1_TID(stid) |
+		     MAS1_TSIZE(BOOK3E_PAGESZ_4K);
+	magic.mas2 = vcpu->arch.magic_page_ea | MAS2_M;
+	magic.mas7_3 = ((u64)pfn << PAGE_SHIFT) |
+		       MAS3_SW | MAS3_SR | MAS3_UW | MAS3_UR;
+	magic.mas8 = 0;
+
+	__write_host_tlbe(&magic, MAS0_TLBSEL(1) | MAS0_ESEL(tlbcam_index));
+	preempt_enable();
+}
+#endif
+
+void inval_gtlbe_on_host(struct kvmppc_vcpu_e500 *vcpu_e500, int tlbsel,
+			 int esel)
+{
+	struct kvm_book3e_206_tlb_entry *gtlbe =
+		get_entry(vcpu_e500, tlbsel, esel);
+	struct tlbe_ref *ref = &vcpu_e500->gtlb_priv[tlbsel][esel].ref;
+
+	/* Don't bother with unmapped entries */
+	if (!(ref->flags & E500_TLB_VALID))
+		return;
+
+	if (tlbsel == 1 && ref->flags & E500_TLB_BITMAP) {
+		u64 tmp = vcpu_e500->g2h_tlb1_map[esel];
+		int hw_tlb_indx;
+		unsigned long flags;
+
+		local_irq_save(flags);
+		while (tmp) {
+			hw_tlb_indx = __ilog2_u64(tmp & -tmp);
+			mtspr(SPRN_MAS0,
+			      MAS0_TLBSEL(1) |
+			      MAS0_ESEL(to_htlb1_esel(hw_tlb_indx)));
+			mtspr(SPRN_MAS1, 0);
+			asm volatile("tlbwe");
+			vcpu_e500->h2g_tlb1_rmap[hw_tlb_indx] = 0;
+			tmp &= tmp - 1;
+		}
+		mb();
+		vcpu_e500->g2h_tlb1_map[esel] = 0;
+		ref->flags &= ~(E500_TLB_BITMAP | E500_TLB_VALID);
+		local_irq_restore(flags);
+
+		return;
+	}
+
+	/* Guest tlbe is backed by at most one host tlbe per shadow pid. */
+	kvmppc_e500_tlbil_one(vcpu_e500, gtlbe);
+
+	/* Mark the TLB as not backed by the host anymore */
+	ref->flags &= ~E500_TLB_VALID;
+}
+
+static inline int tlbe_is_writable(struct kvm_book3e_206_tlb_entry *tlbe)
+{
+	return tlbe->mas7_3 & (MAS3_SW|MAS3_UW);
+}
+
+static inline void kvmppc_e500_ref_setup(struct tlbe_ref *ref,
+					 struct kvm_book3e_206_tlb_entry *gtlbe,
+					 pfn_t pfn)
+{
+	ref->pfn = pfn;
+	ref->flags = E500_TLB_VALID;
+
+	if (tlbe_is_writable(gtlbe))
+		kvm_set_pfn_dirty(pfn);
+}
+
+static inline void kvmppc_e500_ref_release(struct tlbe_ref *ref)
+{
+	if (ref->flags & E500_TLB_VALID) {
+		trace_kvm_booke206_ref_release(ref->pfn, ref->flags);
+		ref->flags = 0;
+	}
+}
+
+void clear_tlb1_bitmap(struct kvmppc_vcpu_e500 *vcpu_e500)
+{
+	if (vcpu_e500->g2h_tlb1_map)
+		memset(vcpu_e500->g2h_tlb1_map, 0,
+		       sizeof(u64) * vcpu_e500->gtlb_params[1].entries);
+	if (vcpu_e500->h2g_tlb1_rmap)
+		memset(vcpu_e500->h2g_tlb1_rmap, 0,
+		       sizeof(unsigned int) * host_tlb_params[1].entries);
+}
+
+static void clear_tlb_privs(struct kvmppc_vcpu_e500 *vcpu_e500)
+{
+	int tlbsel = 0;
+	int i;
+
+	for (i = 0; i < vcpu_e500->gtlb_params[tlbsel].entries; i++) {
+		struct tlbe_ref *ref =
+			&vcpu_e500->gtlb_priv[tlbsel][i].ref;
+		kvmppc_e500_ref_release(ref);
+	}
+}
+
+void clear_tlb_refs(struct kvmppc_vcpu_e500 *vcpu_e500)
+{
+	int stlbsel = 1;
+	int i;
+
+	kvmppc_e500_tlbil_all(vcpu_e500);
+
+	for (i = 0; i < host_tlb_params[stlbsel].entries; i++) {
+		struct tlbe_ref *ref =
+			&vcpu_e500->tlb_refs[stlbsel][i];
+		kvmppc_e500_ref_release(ref);
+	}
+
+	clear_tlb_privs(vcpu_e500);
+}
+
+void kvmppc_core_flush_tlb(struct kvm_vcpu *vcpu)
+{
+	struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
+	clear_tlb_refs(vcpu_e500);
+	clear_tlb1_bitmap(vcpu_e500);
+}
+
+/* TID must be supplied by the caller */
+static void kvmppc_e500_setup_stlbe(
+	struct kvm_vcpu *vcpu,
+	struct kvm_book3e_206_tlb_entry *gtlbe,
+	int tsize, struct tlbe_ref *ref, u64 gvaddr,
+	struct kvm_book3e_206_tlb_entry *stlbe)
+{
+	pfn_t pfn = ref->pfn;
+	u32 pr = vcpu->arch.shared->msr & MSR_PR;
+
+	BUG_ON(!(ref->flags & E500_TLB_VALID));
+
+	/* Force IPROT=0 for all guest mappings. */
+	stlbe->mas1 = MAS1_TSIZE(tsize) | get_tlb_sts(gtlbe) | MAS1_VALID;
+	stlbe->mas2 = (gvaddr & MAS2_EPN) |
+		      e500_shadow_mas2_attrib(gtlbe->mas2, pr);
+	stlbe->mas7_3 = ((u64)pfn << PAGE_SHIFT) |
+			e500_shadow_mas3_attrib(gtlbe->mas7_3, pr);
+
+#ifdef CONFIG_KVM_BOOKE_HV
+	stlbe->mas8 = MAS8_TGS | vcpu->kvm->arch.lpid;
+#endif
+}
+
+static inline int kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
+	u64 gvaddr, gfn_t gfn, struct kvm_book3e_206_tlb_entry *gtlbe,
+	int tlbsel, struct kvm_book3e_206_tlb_entry *stlbe,
+	struct tlbe_ref *ref)
+{
+	struct kvm_memory_slot *slot;
+	unsigned long pfn = 0; /* silence GCC warning */
+	unsigned long hva;
+	int pfnmap = 0;
+	int tsize = BOOK3E_PAGESZ_4K;
+
+	/*
+	 * Translate guest physical to true physical, acquiring
+	 * a page reference if it is normal, non-reserved memory.
+	 *
+	 * gfn_to_memslot() must succeed because otherwise we wouldn't
+	 * have gotten this far.  Eventually we should just pass the slot
+	 * pointer through from the first lookup.
+	 */
+	slot = gfn_to_memslot(vcpu_e500->vcpu.kvm, gfn);
+	hva = gfn_to_hva_memslot(slot, gfn);
+
+	if (tlbsel == 1) {
+		struct vm_area_struct *vma;
+		down_read(&current->mm->mmap_sem);
+
+		vma = find_vma(current->mm, hva);
+		if (vma && hva >= vma->vm_start &&
+		    (vma->vm_flags & VM_PFNMAP)) {
+			/*
+			 * This VMA is a physically contiguous region (e.g.
+			 * /dev/mem) that bypasses normal Linux page
+			 * management.  Find the overlap between the
+			 * vma and the memslot.
+			 */
+
+			unsigned long start, end;
+			unsigned long slot_start, slot_end;
+
+			pfnmap = 1;
+
+			start = vma->vm_pgoff;
+			end = start +
+			      ((vma->vm_end - vma->vm_start) >> PAGE_SHIFT);
+
+			pfn = start + ((hva - vma->vm_start) >> PAGE_SHIFT);
+
+			slot_start = pfn - (gfn - slot->base_gfn);
+			slot_end = slot_start + slot->npages;
+
+			if (start < slot_start)
+				start = slot_start;
+			if (end > slot_end)
+				end = slot_end;
+
+			tsize = (gtlbe->mas1 & MAS1_TSIZE_MASK) >>
+				MAS1_TSIZE_SHIFT;
+
+			/*
+			 * e500 doesn't implement the lowest tsize bit,
+			 * or 1K pages.
+			 */
+			tsize = max(BOOK3E_PAGESZ_4K, tsize & ~1);
+
+			/*
+			 * Now find the largest tsize (up to what the guest
+			 * requested) that will cover gfn, stay within the
+			 * range, and for which gfn and pfn are mutually
+			 * aligned.
+			 */
+
+			for (; tsize > BOOK3E_PAGESZ_4K; tsize -= 2) {
+				unsigned long gfn_start, gfn_end, tsize_pages;
+				tsize_pages = 1 << (tsize - 2);
+
+				gfn_start = gfn & ~(tsize_pages - 1);
+				gfn_end = gfn_start + tsize_pages;
+
+				if (gfn_start + pfn - gfn < start)
+					continue;
+				if (gfn_end + pfn - gfn > end)
+					continue;
+				if ((gfn & (tsize_pages - 1)) !=
+				    (pfn & (tsize_pages - 1)))
+					continue;
+
+				gvaddr &= ~((tsize_pages << PAGE_SHIFT) - 1);
+				pfn &= ~(tsize_pages - 1);
+				break;
+			}
+		} else if (vma && hva >= vma->vm_start &&
+			   (vma->vm_flags & VM_HUGETLB)) {
+			unsigned long psize = vma_kernel_pagesize(vma);
+
+			tsize = (gtlbe->mas1 & MAS1_TSIZE_MASK) >>
+				MAS1_TSIZE_SHIFT;
+
+			/*
+			 * Take the largest page size that satisfies both host
+			 * and guest mapping
+			 */
+			tsize = min(__ilog2(psize) - 10, tsize);
+
+			/*
+			 * e500 doesn't implement the lowest tsize bit,
+			 * or 1K pages.
+			 */
+			tsize = max(BOOK3E_PAGESZ_4K, tsize & ~1);
+		}
+
+		up_read(&current->mm->mmap_sem);
+	}
+
+	if (likely(!pfnmap)) {
+		unsigned long tsize_pages = 1 << (tsize + 10 - PAGE_SHIFT);
+		pfn = gfn_to_pfn_memslot(slot, gfn);
+		if (is_error_noslot_pfn(pfn)) {
+			printk(KERN_ERR "Couldn't get real page for gfn %lx!\n",
+					(long)gfn);
+			return -EINVAL;
+		}
+
+		/* Align guest and physical address to page map boundaries */
+		pfn &= ~(tsize_pages - 1);
+		gvaddr &= ~((tsize_pages << PAGE_SHIFT) - 1);
+	}
+
+	/* Drop old ref and setup new one. */
+	kvmppc_e500_ref_release(ref);
+	kvmppc_e500_ref_setup(ref, gtlbe, pfn);
+
+	kvmppc_e500_setup_stlbe(&vcpu_e500->vcpu, gtlbe, tsize,
+				ref, gvaddr, stlbe);
+
+	/* Clear i-cache for new pages */
+	kvmppc_mmu_flush_icache(pfn);
+
+	/* Drop refcount on page, so that mmu notifiers can clear it */
+	kvm_release_pfn_clean(pfn);
+
+	return 0;
+}
+
+/* XXX only map the one-one case, for now use TLB0 */
+static int kvmppc_e500_tlb0_map(struct kvmppc_vcpu_e500 *vcpu_e500, int esel,
+				struct kvm_book3e_206_tlb_entry *stlbe)
+{
+	struct kvm_book3e_206_tlb_entry *gtlbe;
+	struct tlbe_ref *ref;
+	int stlbsel = 0;
+	int sesel = 0;
+	int r;
+
+	gtlbe = get_entry(vcpu_e500, 0, esel);
+	ref = &vcpu_e500->gtlb_priv[0][esel].ref;
+
+	r = kvmppc_e500_shadow_map(vcpu_e500, get_tlb_eaddr(gtlbe),
+			get_tlb_raddr(gtlbe) >> PAGE_SHIFT,
+			gtlbe, 0, stlbe, ref);
+	if (r)
+		return r;
+
+	write_stlbe(vcpu_e500, gtlbe, stlbe, stlbsel, sesel);
+
+	return 0;
+}
+
+/* Caller must ensure that the specified guest TLB entry is safe to insert into
+ * the shadow TLB. */
+/* XXX for both one-one and one-to-many , for now use TLB1 */
+static int kvmppc_e500_tlb1_map(struct kvmppc_vcpu_e500 *vcpu_e500,
+		u64 gvaddr, gfn_t gfn, struct kvm_book3e_206_tlb_entry *gtlbe,
+		struct kvm_book3e_206_tlb_entry *stlbe, int esel)
+{
+	struct tlbe_ref *ref;
+	unsigned int sesel;
+	int r;
+	int stlbsel = 1;
+
+	sesel = vcpu_e500->host_tlb1_nv++;
+
+	if (unlikely(vcpu_e500->host_tlb1_nv >= tlb1_max_shadow_size()))
+		vcpu_e500->host_tlb1_nv = 0;
+
+	ref = &vcpu_e500->tlb_refs[1][sesel];
+	r = kvmppc_e500_shadow_map(vcpu_e500, gvaddr, gfn, gtlbe, 1, stlbe,
+				   ref);
+	if (r)
+		return r;
+
+	vcpu_e500->g2h_tlb1_map[esel] |= (u64)1 << sesel;
+	vcpu_e500->gtlb_priv[1][esel].ref.flags |= E500_TLB_BITMAP;
+	if (vcpu_e500->h2g_tlb1_rmap[sesel]) {
+		unsigned int idx = vcpu_e500->h2g_tlb1_rmap[sesel];
+		vcpu_e500->g2h_tlb1_map[idx] &= ~(1ULL << sesel);
+	}
+	vcpu_e500->h2g_tlb1_rmap[sesel] = esel;
+
+	write_stlbe(vcpu_e500, gtlbe, stlbe, stlbsel, sesel);
+
+	return 0;
+}
+
+void kvmppc_mmu_map(struct kvm_vcpu *vcpu, u64 eaddr, gpa_t gpaddr,
+		    unsigned int index)
+{
+	struct kvmppc_vcpu_e500 *vcpu_e500 = to_e500(vcpu);
+	struct tlbe_priv *priv;
+	struct kvm_book3e_206_tlb_entry *gtlbe, stlbe;
+	int tlbsel = tlbsel_of(index);
+	int esel = esel_of(index);
+
+	gtlbe = get_entry(vcpu_e500, tlbsel, esel);
+
+	switch (tlbsel) {
+	case 0:
+		priv = &vcpu_e500->gtlb_priv[tlbsel][esel];
+
+		/* Triggers after clear_tlb_refs or on initial mapping */
+		if (!(priv->ref.flags & E500_TLB_VALID)) {
+			kvmppc_e500_tlb0_map(vcpu_e500, esel, &stlbe);
+		} else {
+			kvmppc_e500_setup_stlbe(vcpu, gtlbe, BOOK3E_PAGESZ_4K,
+						&priv->ref, eaddr, &stlbe);
+			write_stlbe(vcpu_e500, gtlbe, &stlbe, 0, 0);
+		}
+		break;
+
+	case 1: {
+		gfn_t gfn = gpaddr >> PAGE_SHIFT;
+		kvmppc_e500_tlb1_map(vcpu_e500, eaddr, gfn, gtlbe, &stlbe,
+				     esel);
+		break;
+	}
+
+	default:
+		BUG();
+		break;
+	}
+}
+
+/************* MMU Notifiers *************/
+
+int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
+{
+	trace_kvm_unmap_hva(hva);
+
+	/*
+	 * Flush all shadow tlb entries everywhere. This is slow, but
+	 * we are 100% sure that we catch the to be unmapped page
+	 */
+	kvm_flush_remote_tlbs(kvm);
+
+	return 0;
+}
+
+int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end)
+{
+	/* kvm_unmap_hva flushes everything anyways */
+	kvm_unmap_hva(kvm, start);
+
+	return 0;
+}
+
+int kvm_age_hva(struct kvm *kvm, unsigned long hva)
+{
+	/* XXX could be more clever ;) */
+	return 0;
+}
+
+int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
+{
+	/* XXX could be more clever ;) */
+	return 0;
+}
+
+void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
+{
+	/* The page will get remapped properly on its next fault */
+	kvm_unmap_hva(kvm, hva);
+}
+
+/*****************************************/
+
+int e500_mmu_host_init(struct kvmppc_vcpu_e500 *vcpu_e500)
+{
+	host_tlb_params[0].entries = mfspr(SPRN_TLB0CFG) & TLBnCFG_N_ENTRY;
+	host_tlb_params[1].entries = mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY;
+
+	/*
+	 * This should never happen on real e500 hardware, but is
+	 * architecturally possible -- e.g. in some weird nested
+	 * virtualization case.
+	 */
+	if (host_tlb_params[0].entries == 0 ||
+	    host_tlb_params[1].entries == 0) {
+		pr_err("%s: need to know host tlb size\n", __func__);
+		return -ENODEV;
+	}
+
+	host_tlb_params[0].ways = (mfspr(SPRN_TLB0CFG) & TLBnCFG_ASSOC) >>
+				  TLBnCFG_ASSOC_SHIFT;
+	host_tlb_params[1].ways = host_tlb_params[1].entries;
+
+	if (!is_power_of_2(host_tlb_params[0].entries) ||
+	    !is_power_of_2(host_tlb_params[0].ways) ||
+	    host_tlb_params[0].entries < host_tlb_params[0].ways ||
+	    host_tlb_params[0].ways == 0) {
+		pr_err("%s: bad tlb0 host config: %u entries %u ways\n",
+		       __func__, host_tlb_params[0].entries,
+		       host_tlb_params[0].ways);
+		return -ENODEV;
+	}
+
+	host_tlb_params[0].sets =
+		host_tlb_params[0].entries / host_tlb_params[0].ways;
+	host_tlb_params[1].sets = 1;
+
+	vcpu_e500->tlb_refs[0] =
+		kzalloc(sizeof(struct tlbe_ref) * host_tlb_params[0].entries,
+			GFP_KERNEL);
+	if (!vcpu_e500->tlb_refs[0])
+		goto err;
+
+	vcpu_e500->tlb_refs[1] =
+		kzalloc(sizeof(struct tlbe_ref) * host_tlb_params[1].entries,
+			GFP_KERNEL);
+	if (!vcpu_e500->tlb_refs[1])
+		goto err;
+
+	vcpu_e500->h2g_tlb1_rmap = kzalloc(sizeof(unsigned int) *
+					   host_tlb_params[1].entries,
+					   GFP_KERNEL);
+	if (!vcpu_e500->h2g_tlb1_rmap)
+		goto err;
+
+	return 0;
+
+err:
+	kfree(vcpu_e500->tlb_refs[0]);
+	kfree(vcpu_e500->tlb_refs[1]);
+	return -EINVAL;
+}
+
+void e500_mmu_host_uninit(struct kvmppc_vcpu_e500 *vcpu_e500)
+{
+	kfree(vcpu_e500->h2g_tlb1_rmap);
+	kfree(vcpu_e500->tlb_refs[0]);
+	kfree(vcpu_e500->tlb_refs[1]);
+}