arch/powerpc/kvm/book3s_32_mmu_host.c - arm/linux-arm64-legacy - Git at Google

 /*
  * Copyright (C) 2010 SUSE Linux Products GmbH. All rights reserved.
  *
  * Authors:
  *     Alexander Graf <agraf@suse.de>
  *
  * 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.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  */

 #include <linux/kvm_host.h>

 #include <asm/kvm_ppc.h>
 #include <asm/kvm_book3s.h>
 #include <asm/mmu-hash32.h>
 #include <asm/machdep.h>
 #include <asm/mmu_context.h>
 #include <asm/hw_irq.h>

 /* #define DEBUG_MMU */
 /* #define DEBUG_SR */

 #ifdef DEBUG_MMU
 #define dprintk_mmu(a, ...) printk(KERN_INFO a, __VA_ARGS__)
 #else
 #define dprintk_mmu(a, ...) do { } while(0)
 #endif

 #ifdef DEBUG_SR
 #define dprintk_sr(a, ...) printk(KERN_INFO a, __VA_ARGS__)
 #else
 #define dprintk_sr(a, ...) do { } while(0)
 #endif

 #if PAGE_SHIFT != 12
 #error Unknown page size
 #endif

 #ifdef CONFIG_SMP
 #error XXX need to grab mmu_hash_lock
 #endif

 #ifdef CONFIG_PTE_64BIT
 #error Only 32 bit pages are supported for now
 #endif

 static ulong htab;
 static u32 htabmask;

 void kvmppc_mmu_invalidate_pte(struct kvm_vcpu *vcpu, struct hpte_cache *pte)
 {
 	volatile u32 *pteg;

 	/* Remove from host HTAB */
 	pteg = (u32*)pte->slot;
 	pteg[0] = 0;

 	/* And make sure it's gone from the TLB too */
 	asm volatile ("sync");
 	asm volatile ("tlbie %0" : : "r" (pte->pte.eaddr) : "memory");
 	asm volatile ("sync");
 	asm volatile ("tlbsync");
 }

 /* We keep 512 gvsid->hvsid entries, mapping the guest ones to the array using
  * a hash, so we don't waste cycles on looping */
 static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid)
 {
 	return (u16)(((gvsid >> (SID_MAP_BITS * 7)) & SID_MAP_MASK) ^
 		     ((gvsid >> (SID_MAP_BITS * 6)) & SID_MAP_MASK) ^
 		     ((gvsid >> (SID_MAP_BITS * 5)) & SID_MAP_MASK) ^
 		     ((gvsid >> (SID_MAP_BITS * 4)) & SID_MAP_MASK) ^
 		     ((gvsid >> (SID_MAP_BITS * 3)) & SID_MAP_MASK) ^
 		     ((gvsid >> (SID_MAP_BITS * 2)) & SID_MAP_MASK) ^
 		     ((gvsid >> (SID_MAP_BITS * 1)) & SID_MAP_MASK) ^
 		     ((gvsid >> (SID_MAP_BITS * 0)) & SID_MAP_MASK));
 }


 static struct kvmppc_sid_map *find_sid_vsid(struct kvm_vcpu *vcpu, u64 gvsid)
 {
 	struct kvmppc_sid_map *map;
 	u16 sid_map_mask;

 	if (kvmppc_get_msr(vcpu) & MSR_PR)
 		gvsid |= VSID_PR;

 	sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
 	map = &to_book3s(vcpu)->sid_map[sid_map_mask];
 	if (map->guest_vsid == gvsid) {
 		dprintk_sr("SR: Searching 0x%llx -> 0x%llx\n",
 			    gvsid, map->host_vsid);
 		return map;
 	}

 	map = &to_book3s(vcpu)->sid_map[SID_MAP_MASK - sid_map_mask];
 	if (map->guest_vsid == gvsid) {
 		dprintk_sr("SR: Searching 0x%llx -> 0x%llx\n",
 			    gvsid, map->host_vsid);
 		return map;
 	}

 	dprintk_sr("SR: Searching 0x%llx -> not found\n", gvsid);
 	return NULL;
 }

 static u32 *kvmppc_mmu_get_pteg(struct kvm_vcpu *vcpu, u32 vsid, u32 eaddr,
 				bool primary)
 {
 	u32 page, hash;
 	ulong pteg = htab;

 	page = (eaddr & ~ESID_MASK) >> 12;

 	hash = ((vsid ^ page) << 6);
 	if (!primary)
 		hash = ~hash;

 	hash &= htabmask;

 	pteg |= hash;

 	dprintk_mmu("htab: %lx | hash: %x | htabmask: %x | pteg: %lx\n",
 		htab, hash, htabmask, pteg);

 	return (u32*)pteg;
 }

 extern char etext[];

 int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte,
 			bool iswrite)
 {
 	pfn_t hpaddr;
 	u64 vpn;
 	u64 vsid;
 	struct kvmppc_sid_map *map;
 	volatile u32 *pteg;
 	u32 eaddr = orig_pte->eaddr;
 	u32 pteg0, pteg1;
 	register int rr = 0;
 	bool primary = false;
 	bool evict = false;
 	struct hpte_cache *pte;
 	int r = 0;
 	bool writable;

 	/* Get host physical address for gpa */
 	hpaddr = kvmppc_gfn_to_pfn(vcpu, orig_pte->raddr >> PAGE_SHIFT,
 				   iswrite, &writable);
 	if (is_error_noslot_pfn(hpaddr)) {
 		printk(KERN_INFO "Couldn't get guest page for gfn %lx!\n",
 				 orig_pte->eaddr);
 		r = -EINVAL;
 		goto out;
 	}
 	hpaddr <<= PAGE_SHIFT;

 	/* and write the mapping ea -> hpa into the pt */
 	vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid);
 	map = find_sid_vsid(vcpu, vsid);
 	if (!map) {
 		kvmppc_mmu_map_segment(vcpu, eaddr);
 		map = find_sid_vsid(vcpu, vsid);
 	}
 	BUG_ON(!map);

 	vsid = map->host_vsid;
 	vpn = (vsid << (SID_SHIFT - VPN_SHIFT)) |
 		((eaddr & ~ESID_MASK) >> VPN_SHIFT);
 next_pteg:
 	if (rr == 16) {
 		primary = !primary;
 		evict = true;
 		rr = 0;
 	}

 	pteg = kvmppc_mmu_get_pteg(vcpu, vsid, eaddr, primary);

 	/* not evicting yet */
 	if (!evict && (pteg[rr] & PTE_V)) {
 		rr += 2;
 		goto next_pteg;
 	}

 	dprintk_mmu("KVM: old PTEG: %p (%d)\n", pteg, rr);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[0], pteg[1]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[2], pteg[3]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[4], pteg[5]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[6], pteg[7]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[8], pteg[9]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[10], pteg[11]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[12], pteg[13]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[14], pteg[15]);

 	pteg0 = ((eaddr & 0x0fffffff) >> 22) | (vsid << 7) | PTE_V |
 		(primary ? 0 : PTE_SEC);
 	pteg1 = hpaddr | PTE_M | PTE_R | PTE_C;

 	if (orig_pte->may_write && writable) {
 		pteg1 |= PP_RWRW;
 		mark_page_dirty(vcpu->kvm, orig_pte->raddr >> PAGE_SHIFT);
 	} else {
 		pteg1 |= PP_RWRX;
 	}

 	if (orig_pte->may_execute)
 		kvmppc_mmu_flush_icache(hpaddr >> PAGE_SHIFT);

 	local_irq_disable();

 	if (pteg[rr]) {
 		pteg[rr] = 0;
 		asm volatile ("sync");
 	}
 	pteg[rr + 1] = pteg1;
 	pteg[rr] = pteg0;
 	asm volatile ("sync");

 	local_irq_enable();

 	dprintk_mmu("KVM: new PTEG: %p\n", pteg);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[0], pteg[1]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[2], pteg[3]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[4], pteg[5]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[6], pteg[7]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[8], pteg[9]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[10], pteg[11]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[12], pteg[13]);
 	dprintk_mmu("KVM:   %08x - %08x\n", pteg[14], pteg[15]);


 	/* Now tell our Shadow PTE code about the new page */

 	pte = kvmppc_mmu_hpte_cache_next(vcpu);
 	if (!pte) {
 		kvm_release_pfn_clean(hpaddr >> PAGE_SHIFT);
 		r = -EAGAIN;
 		goto out;
 	}

 	dprintk_mmu("KVM: %c%c Map 0x%llx: [%lx] 0x%llx (0x%llx) -> %lx\n",
 		    orig_pte->may_write ? 'w' : '-',
 		    orig_pte->may_execute ? 'x' : '-',
 		    orig_pte->eaddr, (ulong)pteg, vpn,
 		    orig_pte->vpage, hpaddr);

 	pte->slot = (ulong)&pteg[rr];
 	pte->host_vpn = vpn;
 	pte->pte = *orig_pte;
 	pte->pfn = hpaddr >> PAGE_SHIFT;

 	kvmppc_mmu_hpte_cache_map(vcpu, pte);

 	kvm_release_pfn_clean(hpaddr >> PAGE_SHIFT);
 out:
 	return r;
 }

 void kvmppc_mmu_unmap_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *pte)
 {
 	kvmppc_mmu_pte_vflush(vcpu, pte->vpage, 0xfffffffffULL);
 }

 static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid)
 {
 	struct kvmppc_sid_map *map;
 	struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
 	u16 sid_map_mask;
 	static int backwards_map = 0;

 	if (kvmppc_get_msr(vcpu) & MSR_PR)
 		gvsid |= VSID_PR;

 	/* We might get collisions that trap in preceding order, so let's
 	   map them differently */

 	sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
 	if (backwards_map)
 		sid_map_mask = SID_MAP_MASK - sid_map_mask;

 	map = &to_book3s(vcpu)->sid_map[sid_map_mask];

 	/* Make sure we're taking the other map next time */
 	backwards_map = !backwards_map;

 	/* Uh-oh ... out of mappings. Let's flush! */
 	if (vcpu_book3s->vsid_next >= VSID_POOL_SIZE) {
 		vcpu_book3s->vsid_next = 0;
 		memset(vcpu_book3s->sid_map, 0,
 		       sizeof(struct kvmppc_sid_map) * SID_MAP_NUM);
 		kvmppc_mmu_pte_flush(vcpu, 0, 0);
 		kvmppc_mmu_flush_segments(vcpu);
 	}
 	map->host_vsid = vcpu_book3s->vsid_pool[vcpu_book3s->vsid_next];
 	vcpu_book3s->vsid_next++;

 	map->guest_vsid = gvsid;
 	map->valid = true;

 	return map;
 }

 int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr)
 {
 	u32 esid = eaddr >> SID_SHIFT;
 	u64 gvsid;
 	u32 sr;
 	struct kvmppc_sid_map *map;
 	struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
 	int r = 0;

 	if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) {
 		/* Invalidate an entry */
 		svcpu->sr[esid] = SR_INVALID;
 		r = -ENOENT;
 		goto out;
 	}

 	map = find_sid_vsid(vcpu, gvsid);
 	if (!map)
 		map = create_sid_map(vcpu, gvsid);

 	map->guest_esid = esid;
 	sr = map->host_vsid | SR_KP;
 	svcpu->sr[esid] = sr;

 	dprintk_sr("MMU: mtsr %d, 0x%x\n", esid, sr);

 out:
 	svcpu_put(svcpu);
 	return r;
 }

 void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu)
 {
 	int i;
 	struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);

 	dprintk_sr("MMU: flushing all segments (%d)\n", ARRAY_SIZE(svcpu->sr));
 	for (i = 0; i < ARRAY_SIZE(svcpu->sr); i++)
 		svcpu->sr[i] = SR_INVALID;

 	svcpu_put(svcpu);
 }

 void kvmppc_mmu_destroy_pr(struct kvm_vcpu *vcpu)
 {
 	int i;

 	kvmppc_mmu_hpte_destroy(vcpu);
 	preempt_disable();
 	for (i = 0; i < SID_CONTEXTS; i++)
 		__destroy_context(to_book3s(vcpu)->context_id[i]);
 	preempt_enable();
 }

 /* From mm/mmu_context_hash32.c */
 #define CTX_TO_VSID(c, id)	((((c) * (897 * 16)) + (id * 0x111)) & 0xffffff)

 int kvmppc_mmu_init(struct kvm_vcpu *vcpu)
 {
 	struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu);
 	int err;
 	ulong sdr1;
 	int i;
 	int j;

 	for (i = 0; i < SID_CONTEXTS; i++) {
 		err = __init_new_context();
 		if (err < 0)
 			goto init_fail;
 		vcpu3s->context_id[i] = err;

 		/* Remember context id for this combination */
 		for (j = 0; j < 16; j++)
 			vcpu3s->vsid_pool[(i * 16) + j] = CTX_TO_VSID(err, j);
 	}

 	vcpu3s->vsid_next = 0;

 	/* Remember where the HTAB is */
 	asm ( "mfsdr1 %0" : "=r"(sdr1) );
 	htabmask = ((sdr1 & 0x1FF) << 16) | 0xFFC0;
 	htab = (ulong)__va(sdr1 & 0xffff0000);

 	kvmppc_mmu_hpte_init(vcpu);

 	return 0;

 init_fail:
 	for (j = 0; j < i; j++) {
 		if (!vcpu3s->context_id[j])
 			continue;

 		__destroy_context(to_book3s(vcpu)->context_id[j]);
 	}

 	return -1;
 }
	/*
	* Copyright (C) 2010 SUSE Linux Products GmbH. All rights reserved.
	*
	* Authors:
	* Alexander Graf <agraf@suse.de>
	*
	* 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.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
	*/

	#include <linux/kvm_host.h>

	#include <asm/kvm_ppc.h>
	#include <asm/kvm_book3s.h>
	#include <asm/mmu-hash32.h>
	#include <asm/machdep.h>
	#include <asm/mmu_context.h>
	#include <asm/hw_irq.h>

	/* #define DEBUG_MMU */
	/* #define DEBUG_SR */

	#ifdef DEBUG_MMU
	#define dprintk_mmu(a, ...) printk(KERN_INFO a, __VA_ARGS__)
	#else
	#define dprintk_mmu(a, ...) do { } while(0)
	#endif

	#ifdef DEBUG_SR
	#define dprintk_sr(a, ...) printk(KERN_INFO a, __VA_ARGS__)
	#else
	#define dprintk_sr(a, ...) do { } while(0)
	#endif

	#if PAGE_SHIFT != 12
	#error Unknown page size
	#endif

	#ifdef CONFIG_SMP
	#error XXX need to grab mmu_hash_lock
	#endif

	#ifdef CONFIG_PTE_64BIT
	#error Only 32 bit pages are supported for now
	#endif

	static ulong htab;
	static u32 htabmask;

	void kvmppc_mmu_invalidate_pte(struct kvm_vcpu vcpu, struct hpte_cache pte)
	{
	volatile u32 *pteg;

	/* Remove from host HTAB */
	pteg = (u32*)pte->slot;
	pteg[0] = 0;

	/* And make sure it's gone from the TLB too */
	asm volatile ("sync");
	asm volatile ("tlbie %0" : : "r" (pte->pte.eaddr) : "memory");
	asm volatile ("sync");
	asm volatile ("tlbsync");
	}

	/* We keep 512 gvsid->hvsid entries, mapping the guest ones to the array using
	* a hash, so we don't waste cycles on looping */
	static u16 kvmppc_sid_hash(struct kvm_vcpu *vcpu, u64 gvsid)
	{
	return (u16)(((gvsid >> (SID_MAP_BITS * 7)) & SID_MAP_MASK) ^
	((gvsid >> (SID_MAP_BITS * 6)) & SID_MAP_MASK) ^
	((gvsid >> (SID_MAP_BITS * 5)) & SID_MAP_MASK) ^
	((gvsid >> (SID_MAP_BITS * 4)) & SID_MAP_MASK) ^
	((gvsid >> (SID_MAP_BITS * 3)) & SID_MAP_MASK) ^
	((gvsid >> (SID_MAP_BITS * 2)) & SID_MAP_MASK) ^
	((gvsid >> (SID_MAP_BITS * 1)) & SID_MAP_MASK) ^
	((gvsid >> (SID_MAP_BITS * 0)) & SID_MAP_MASK));
	}


	static struct kvmppc_sid_map find_sid_vsid(struct kvm_vcpu vcpu, u64 gvsid)
	{
	struct kvmppc_sid_map *map;
	u16 sid_map_mask;

	if (kvmppc_get_msr(vcpu) & MSR_PR)
	gvsid \|= VSID_PR;

	sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
	map = &to_book3s(vcpu)->sid_map[sid_map_mask];
	if (map->guest_vsid == gvsid) {
	dprintk_sr("SR: Searching 0x%llx -> 0x%llx\n",
	gvsid, map->host_vsid);
	return map;
	}

	map = &to_book3s(vcpu)->sid_map[SID_MAP_MASK - sid_map_mask];
	if (map->guest_vsid == gvsid) {
	dprintk_sr("SR: Searching 0x%llx -> 0x%llx\n",
	gvsid, map->host_vsid);
	return map;
	}

	dprintk_sr("SR: Searching 0x%llx -> not found\n", gvsid);
	return NULL;
	}

	static u32 kvmppc_mmu_get_pteg(struct kvm_vcpu vcpu, u32 vsid, u32 eaddr,
	bool primary)
	{
	u32 page, hash;
	ulong pteg = htab;

	page = (eaddr & ~ESID_MASK) >> 12;

	hash = ((vsid ^ page) << 6);
	if (!primary)
	hash = ~hash;

	hash &= htabmask;

	pteg \|= hash;

	dprintk_mmu("htab: %lx \| hash: %x \| htabmask: %x \| pteg: %lx\n",
	htab, hash, htabmask, pteg);

	return (u32*)pteg;
	}

	extern char etext[];

	int kvmppc_mmu_map_page(struct kvm_vcpu vcpu, struct kvmppc_pte orig_pte,
	bool iswrite)
	{
	pfn_t hpaddr;
	u64 vpn;
	u64 vsid;
	struct kvmppc_sid_map *map;
	volatile u32 *pteg;
	u32 eaddr = orig_pte->eaddr;
	u32 pteg0, pteg1;
	register int rr = 0;
	bool primary = false;
	bool evict = false;
	struct hpte_cache *pte;
	int r = 0;
	bool writable;

	/* Get host physical address for gpa */
	hpaddr = kvmppc_gfn_to_pfn(vcpu, orig_pte->raddr >> PAGE_SHIFT,
	iswrite, &writable);
	if (is_error_noslot_pfn(hpaddr)) {
	printk(KERN_INFO "Couldn't get guest page for gfn %lx!\n",
	orig_pte->eaddr);
	r = -EINVAL;
	goto out;
	}
	hpaddr <<= PAGE_SHIFT;

	/* and write the mapping ea -> hpa into the pt */
	vcpu->arch.mmu.esid_to_vsid(vcpu, orig_pte->eaddr >> SID_SHIFT, &vsid);
	map = find_sid_vsid(vcpu, vsid);
	if (!map) {
	kvmppc_mmu_map_segment(vcpu, eaddr);
	map = find_sid_vsid(vcpu, vsid);
	}
	BUG_ON(!map);

	vsid = map->host_vsid;
	vpn = (vsid << (SID_SHIFT - VPN_SHIFT)) \|
	((eaddr & ~ESID_MASK) >> VPN_SHIFT);
	next_pteg:
	if (rr == 16) {
	primary = !primary;
	evict = true;
	rr = 0;
	}

	pteg = kvmppc_mmu_get_pteg(vcpu, vsid, eaddr, primary);

	/* not evicting yet */
	if (!evict && (pteg[rr] & PTE_V)) {
	rr += 2;
	goto next_pteg;
	}

	dprintk_mmu("KVM: old PTEG: %p (%d)\n", pteg, rr);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[0], pteg[1]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[2], pteg[3]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[4], pteg[5]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[6], pteg[7]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[8], pteg[9]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[10], pteg[11]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[12], pteg[13]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[14], pteg[15]);

	pteg0 = ((eaddr & 0x0fffffff) >> 22) \| (vsid << 7) \| PTE_V \|
	(primary ? 0 : PTE_SEC);
	pteg1 = hpaddr \| PTE_M \| PTE_R \| PTE_C;

	if (orig_pte->may_write && writable) {
	pteg1 \|= PP_RWRW;
	mark_page_dirty(vcpu->kvm, orig_pte->raddr >> PAGE_SHIFT);
	} else {
	pteg1 \|= PP_RWRX;
	}

	if (orig_pte->may_execute)
	kvmppc_mmu_flush_icache(hpaddr >> PAGE_SHIFT);

	local_irq_disable();

	if (pteg[rr]) {
	pteg[rr] = 0;
	asm volatile ("sync");
	}
	pteg[rr + 1] = pteg1;
	pteg[rr] = pteg0;
	asm volatile ("sync");

	local_irq_enable();

	dprintk_mmu("KVM: new PTEG: %p\n", pteg);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[0], pteg[1]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[2], pteg[3]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[4], pteg[5]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[6], pteg[7]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[8], pteg[9]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[10], pteg[11]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[12], pteg[13]);
	dprintk_mmu("KVM: %08x - %08x\n", pteg[14], pteg[15]);


	/* Now tell our Shadow PTE code about the new page */

	pte = kvmppc_mmu_hpte_cache_next(vcpu);
	if (!pte) {
	kvm_release_pfn_clean(hpaddr >> PAGE_SHIFT);
	r = -EAGAIN;
	goto out;
	}

	dprintk_mmu("KVM: %c%c Map 0x%llx: [%lx] 0x%llx (0x%llx) -> %lx\n",
	orig_pte->may_write ? 'w' : '-',
	orig_pte->may_execute ? 'x' : '-',
	orig_pte->eaddr, (ulong)pteg, vpn,
	orig_pte->vpage, hpaddr);

	pte->slot = (ulong)&pteg[rr];
	pte->host_vpn = vpn;
	pte->pte = *orig_pte;
	pte->pfn = hpaddr >> PAGE_SHIFT;

	kvmppc_mmu_hpte_cache_map(vcpu, pte);

	kvm_release_pfn_clean(hpaddr >> PAGE_SHIFT);
	out:
	return r;
	}

	void kvmppc_mmu_unmap_page(struct kvm_vcpu vcpu, struct kvmppc_pte pte)
	{
	kvmppc_mmu_pte_vflush(vcpu, pte->vpage, 0xfffffffffULL);
	}

	static struct kvmppc_sid_map create_sid_map(struct kvm_vcpu vcpu, u64 gvsid)
	{
	struct kvmppc_sid_map *map;
	struct kvmppc_vcpu_book3s *vcpu_book3s = to_book3s(vcpu);
	u16 sid_map_mask;
	static int backwards_map = 0;

	if (kvmppc_get_msr(vcpu) & MSR_PR)
	gvsid \|= VSID_PR;

	/* We might get collisions that trap in preceding order, so let's
	map them differently */

	sid_map_mask = kvmppc_sid_hash(vcpu, gvsid);
	if (backwards_map)
	sid_map_mask = SID_MAP_MASK - sid_map_mask;

	map = &to_book3s(vcpu)->sid_map[sid_map_mask];

	/* Make sure we're taking the other map next time */
	backwards_map = !backwards_map;

	/* Uh-oh ... out of mappings. Let's flush! */
	if (vcpu_book3s->vsid_next >= VSID_POOL_SIZE) {
	vcpu_book3s->vsid_next = 0;
	memset(vcpu_book3s->sid_map, 0,
	sizeof(struct kvmppc_sid_map) * SID_MAP_NUM);
	kvmppc_mmu_pte_flush(vcpu, 0, 0);
	kvmppc_mmu_flush_segments(vcpu);
	}
	map->host_vsid = vcpu_book3s->vsid_pool[vcpu_book3s->vsid_next];
	vcpu_book3s->vsid_next++;

	map->guest_vsid = gvsid;
	map->valid = true;

	return map;
	}

	int kvmppc_mmu_map_segment(struct kvm_vcpu *vcpu, ulong eaddr)
	{
	u32 esid = eaddr >> SID_SHIFT;
	u64 gvsid;
	u32 sr;
	struct kvmppc_sid_map *map;
	struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);
	int r = 0;

	if (vcpu->arch.mmu.esid_to_vsid(vcpu, esid, &gvsid)) {
	/* Invalidate an entry */
	svcpu->sr[esid] = SR_INVALID;
	r = -ENOENT;
	goto out;
	}

	map = find_sid_vsid(vcpu, gvsid);
	if (!map)
	map = create_sid_map(vcpu, gvsid);

	map->guest_esid = esid;
	sr = map->host_vsid \| SR_KP;
	svcpu->sr[esid] = sr;

	dprintk_sr("MMU: mtsr %d, 0x%x\n", esid, sr);

	out:
	svcpu_put(svcpu);
	return r;
	}

	void kvmppc_mmu_flush_segments(struct kvm_vcpu *vcpu)
	{
	int i;
	struct kvmppc_book3s_shadow_vcpu *svcpu = svcpu_get(vcpu);

	dprintk_sr("MMU: flushing all segments (%d)\n", ARRAY_SIZE(svcpu->sr));
	for (i = 0; i < ARRAY_SIZE(svcpu->sr); i++)
	svcpu->sr[i] = SR_INVALID;

	svcpu_put(svcpu);
	}

	void kvmppc_mmu_destroy_pr(struct kvm_vcpu *vcpu)
	{
	int i;

	kvmppc_mmu_hpte_destroy(vcpu);
	preempt_disable();
	for (i = 0; i < SID_CONTEXTS; i++)
	__destroy_context(to_book3s(vcpu)->context_id[i]);
	preempt_enable();
	}

	/* From mm/mmu_context_hash32.c */
	#define CTX_TO_VSID(c, id) ((((c) * (897 * 16)) + (id * 0x111)) & 0xffffff)

	int kvmppc_mmu_init(struct kvm_vcpu *vcpu)
	{
	struct kvmppc_vcpu_book3s *vcpu3s = to_book3s(vcpu);
	int err;
	ulong sdr1;
	int i;
	int j;

	for (i = 0; i < SID_CONTEXTS; i++) {
	err = __init_new_context();
	if (err < 0)
	goto init_fail;
	vcpu3s->context_id[i] = err;

	/* Remember context id for this combination */
	for (j = 0; j < 16; j++)
	vcpu3s->vsid_pool[(i * 16) + j] = CTX_TO_VSID(err, j);
	}

	vcpu3s->vsid_next = 0;

	/* Remember where the HTAB is */
	asm ( "mfsdr1 %0" : "=r"(sdr1) );
	htabmask = ((sdr1 & 0x1FF) << 16) \| 0xFFC0;
	htab = (ulong)__va(sdr1 & 0xffff0000);

	kvmppc_mmu_hpte_init(vcpu);

	return 0;

	init_fail:
	for (j = 0; j < i; j++) {
	if (!vcpu3s->context_id[j])
	continue;

	__destroy_context(to_book3s(vcpu)->context_id[j]);
	}

	return -1;
	}