arch/mips/kvm/tlb.c - linux - Git at Google

 /*
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
  * for more details.
  *
  * KVM/MIPS TLB handling, this file is part of the Linux host kernel so that
  * TLB handlers run from KSEG0
  *
  * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
  * Authors: Sanjay Lal <sanjayl@kymasys.com>
  */

 #include <linux/sched.h>
 #include <linux/smp.h>
 #include <linux/mm.h>
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/kvm_host.h>
 #include <linux/srcu.h>

 #include <asm/cpu.h>
 #include <asm/bootinfo.h>
 #include <asm/mmu_context.h>
 #include <asm/pgtable.h>
 #include <asm/cacheflush.h>
 #include <asm/tlb.h>

 #undef CONFIG_MIPS_MT
 #include <asm/r4kcache.h>
 #define CONFIG_MIPS_MT

 #define KVM_GUEST_PC_TLB    0
 #define KVM_GUEST_SP_TLB    1

 #define PRIx64 "llx"

 atomic_t kvm_mips_instance;
 EXPORT_SYMBOL(kvm_mips_instance);

 /* These function pointers are initialized once the KVM module is loaded */
 kvm_pfn_t (*kvm_mips_gfn_to_pfn)(struct kvm *kvm, gfn_t gfn);
 EXPORT_SYMBOL(kvm_mips_gfn_to_pfn);

 void (*kvm_mips_release_pfn_clean)(kvm_pfn_t pfn);
 EXPORT_SYMBOL(kvm_mips_release_pfn_clean);

 bool (*kvm_mips_is_error_pfn)(kvm_pfn_t pfn);
 EXPORT_SYMBOL(kvm_mips_is_error_pfn);

 uint32_t kvm_mips_get_kernel_asid(struct kvm_vcpu *vcpu)
 {
 	return vcpu->arch.guest_kernel_asid[smp_processor_id()] & ASID_MASK;
 }

 uint32_t kvm_mips_get_user_asid(struct kvm_vcpu *vcpu)
 {
 	return vcpu->arch.guest_user_asid[smp_processor_id()] & ASID_MASK;
 }

 inline uint32_t kvm_mips_get_commpage_asid(struct kvm_vcpu *vcpu)
 {
 	return vcpu->kvm->arch.commpage_tlb;
 }

 /* Structure defining an tlb entry data set. */

 void kvm_mips_dump_host_tlbs(void)
 {
 	unsigned long old_entryhi;
 	unsigned long old_pagemask;
 	struct kvm_mips_tlb tlb;
 	unsigned long flags;
 	int i;

 	local_irq_save(flags);

 	old_entryhi = read_c0_entryhi();
 	old_pagemask = read_c0_pagemask();

 	kvm_info("HOST TLBs:\n");
 	kvm_info("ASID: %#lx\n", read_c0_entryhi() & ASID_MASK);

 	for (i = 0; i < current_cpu_data.tlbsize; i++) {
 		write_c0_index(i);
 		mtc0_tlbw_hazard();

 		tlb_read();
 		tlbw_use_hazard();

 		tlb.tlb_hi = read_c0_entryhi();
 		tlb.tlb_lo0 = read_c0_entrylo0();
 		tlb.tlb_lo1 = read_c0_entrylo1();
 		tlb.tlb_mask = read_c0_pagemask();

 		kvm_info("TLB%c%3d Hi 0x%08lx ",
 			 (tlb.tlb_lo0 | tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*',
 			 i, tlb.tlb_hi);
 		kvm_info("Lo0=0x%09" PRIx64 " %c%c attr %lx ",
 			 (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo0),
 			 (tlb.tlb_lo0 & MIPS3_PG_D) ? 'D' : ' ',
 			 (tlb.tlb_lo0 & MIPS3_PG_G) ? 'G' : ' ',
 			 (tlb.tlb_lo0 >> 3) & 7);
 		kvm_info("Lo1=0x%09" PRIx64 " %c%c attr %lx sz=%lx\n",
 			 (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo1),
 			 (tlb.tlb_lo1 & MIPS3_PG_D) ? 'D' : ' ',
 			 (tlb.tlb_lo1 & MIPS3_PG_G) ? 'G' : ' ',
 			 (tlb.tlb_lo1 >> 3) & 7, tlb.tlb_mask);
 	}
 	write_c0_entryhi(old_entryhi);
 	write_c0_pagemask(old_pagemask);
 	mtc0_tlbw_hazard();
 	local_irq_restore(flags);
 }
 EXPORT_SYMBOL(kvm_mips_dump_host_tlbs);

 void kvm_mips_dump_guest_tlbs(struct kvm_vcpu *vcpu)
 {
 	struct mips_coproc *cop0 = vcpu->arch.cop0;
 	struct kvm_mips_tlb tlb;
 	int i;

 	kvm_info("Guest TLBs:\n");
 	kvm_info("Guest EntryHi: %#lx\n", kvm_read_c0_guest_entryhi(cop0));

 	for (i = 0; i < KVM_MIPS_GUEST_TLB_SIZE; i++) {
 		tlb = vcpu->arch.guest_tlb[i];
 		kvm_info("TLB%c%3d Hi 0x%08lx ",
 			 (tlb.tlb_lo0 | tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*',
 			 i, tlb.tlb_hi);
 		kvm_info("Lo0=0x%09" PRIx64 " %c%c attr %lx ",
 			 (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo0),
 			 (tlb.tlb_lo0 & MIPS3_PG_D) ? 'D' : ' ',
 			 (tlb.tlb_lo0 & MIPS3_PG_G) ? 'G' : ' ',
 			 (tlb.tlb_lo0 >> 3) & 7);
 		kvm_info("Lo1=0x%09" PRIx64 " %c%c attr %lx sz=%lx\n",
 			 (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo1),
 			 (tlb.tlb_lo1 & MIPS3_PG_D) ? 'D' : ' ',
 			 (tlb.tlb_lo1 & MIPS3_PG_G) ? 'G' : ' ',
 			 (tlb.tlb_lo1 >> 3) & 7, tlb.tlb_mask);
 	}
 }
 EXPORT_SYMBOL(kvm_mips_dump_guest_tlbs);

 static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn)
 {
 	int srcu_idx, err = 0;
 	kvm_pfn_t pfn;

 	if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE)
 		return 0;

 	srcu_idx = srcu_read_lock(&kvm->srcu);
 	pfn = kvm_mips_gfn_to_pfn(kvm, gfn);

 	if (kvm_mips_is_error_pfn(pfn)) {
 		kvm_err("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn);
 		err = -EFAULT;
 		goto out;
 	}

 	kvm->arch.guest_pmap[gfn] = pfn;
 out:
 	srcu_read_unlock(&kvm->srcu, srcu_idx);
 	return err;
 }

 /* Translate guest KSEG0 addresses to Host PA */
 unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu,
 						    unsigned long gva)
 {
 	gfn_t gfn;
 	uint32_t offset = gva & ~PAGE_MASK;
 	struct kvm *kvm = vcpu->kvm;

 	if (KVM_GUEST_KSEGX(gva) != KVM_GUEST_KSEG0) {
 		kvm_err("%s/%p: Invalid gva: %#lx\n", __func__,
 			__builtin_return_address(0), gva);
 		return KVM_INVALID_PAGE;
 	}

 	gfn = (KVM_GUEST_CPHYSADDR(gva) >> PAGE_SHIFT);

 	if (gfn >= kvm->arch.guest_pmap_npages) {
 		kvm_err("%s: Invalid gfn: %#llx, GVA: %#lx\n", __func__, gfn,
 			gva);
 		return KVM_INVALID_PAGE;
 	}

 	if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
 		return KVM_INVALID_ADDR;

 	return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset;
 }
 EXPORT_SYMBOL(kvm_mips_translate_guest_kseg0_to_hpa);

 /* XXXKYMA: Must be called with interrupts disabled */
 /* set flush_dcache_mask == 0 if no dcache flush required */
 int kvm_mips_host_tlb_write(struct kvm_vcpu *vcpu, unsigned long entryhi,
 			    unsigned long entrylo0, unsigned long entrylo1,
 			    int flush_dcache_mask)
 {
 	unsigned long flags;
 	unsigned long old_entryhi;
 	int idx;

 	local_irq_save(flags);

 	old_entryhi = read_c0_entryhi();
 	write_c0_entryhi(entryhi);
 	mtc0_tlbw_hazard();

 	tlb_probe();
 	tlb_probe_hazard();
 	idx = read_c0_index();

 	if (idx > current_cpu_data.tlbsize) {
 		kvm_err("%s: Invalid Index: %d\n", __func__, idx);
 		kvm_mips_dump_host_tlbs();
 		local_irq_restore(flags);
 		return -1;
 	}

 	write_c0_entrylo0(entrylo0);
 	write_c0_entrylo1(entrylo1);
 	mtc0_tlbw_hazard();

 	if (idx < 0)
 		tlb_write_random();
 	else
 		tlb_write_indexed();
 	tlbw_use_hazard();

 	kvm_debug("@ %#lx idx: %2d [entryhi(R): %#lx] entrylo0(R): 0x%08lx, entrylo1(R): 0x%08lx\n",
 		  vcpu->arch.pc, idx, read_c0_entryhi(),
 		  read_c0_entrylo0(), read_c0_entrylo1());

 	/* Flush D-cache */
 	if (flush_dcache_mask) {
 		if (entrylo0 & MIPS3_PG_V) {
 			++vcpu->stat.flush_dcache_exits;
 			flush_data_cache_page((entryhi & VPN2_MASK) &
 					      ~flush_dcache_mask);
 		}
 		if (entrylo1 & MIPS3_PG_V) {
 			++vcpu->stat.flush_dcache_exits;
 			flush_data_cache_page(((entryhi & VPN2_MASK) &
 					       ~flush_dcache_mask) |
 					      (0x1 << PAGE_SHIFT));
 		}
 	}

 	/* Restore old ASID */
 	write_c0_entryhi(old_entryhi);
 	mtc0_tlbw_hazard();
 	tlbw_use_hazard();
 	local_irq_restore(flags);
 	return 0;
 }

 /* XXXKYMA: Must be called with interrupts disabled */
 int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr,
 				    struct kvm_vcpu *vcpu)
 {
 	gfn_t gfn;
 	kvm_pfn_t pfn0, pfn1;
 	unsigned long vaddr = 0;
 	unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
 	int even;
 	struct kvm *kvm = vcpu->kvm;
 	const int flush_dcache_mask = 0;

 	if (KVM_GUEST_KSEGX(badvaddr) != KVM_GUEST_KSEG0) {
 		kvm_err("%s: Invalid BadVaddr: %#lx\n", __func__, badvaddr);
 		kvm_mips_dump_host_tlbs();
 		return -1;
 	}

 	gfn = (KVM_GUEST_CPHYSADDR(badvaddr) >> PAGE_SHIFT);
 	if (gfn >= kvm->arch.guest_pmap_npages) {
 		kvm_err("%s: Invalid gfn: %#llx, BadVaddr: %#lx\n", __func__,
 			gfn, badvaddr);
 		kvm_mips_dump_host_tlbs();
 		return -1;
 	}
 	even = !(gfn & 0x1);
 	vaddr = badvaddr & (PAGE_MASK << 1);

 	if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
 		return -1;

 	if (kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1) < 0)
 		return -1;

 	if (even) {
 		pfn0 = kvm->arch.guest_pmap[gfn];
 		pfn1 = kvm->arch.guest_pmap[gfn ^ 0x1];
 	} else {
 		pfn0 = kvm->arch.guest_pmap[gfn ^ 0x1];
 		pfn1 = kvm->arch.guest_pmap[gfn];
 	}

 	entryhi = (vaddr | kvm_mips_get_kernel_asid(vcpu));
 	entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | (0x3 << 3) |
 		   (1 << 2) | (0x1 << 1);
 	entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) | (0x3 << 3) |
 		   (1 << 2) | (0x1 << 1);

 	return kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
 				       flush_dcache_mask);
 }
 EXPORT_SYMBOL(kvm_mips_handle_kseg0_tlb_fault);

 int kvm_mips_handle_commpage_tlb_fault(unsigned long badvaddr,
 	struct kvm_vcpu *vcpu)
 {
 	kvm_pfn_t pfn0, pfn1;
 	unsigned long flags, old_entryhi = 0, vaddr = 0;
 	unsigned long entrylo0 = 0, entrylo1 = 0;

 	pfn0 = CPHYSADDR(vcpu->arch.kseg0_commpage) >> PAGE_SHIFT;
 	pfn1 = 0;
 	entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | (0x3 << 3) |
 		   (1 << 2) | (0x1 << 1);
 	entrylo1 = 0;

 	local_irq_save(flags);

 	old_entryhi = read_c0_entryhi();
 	vaddr = badvaddr & (PAGE_MASK << 1);
 	write_c0_entryhi(vaddr | kvm_mips_get_kernel_asid(vcpu));
 	mtc0_tlbw_hazard();
 	write_c0_entrylo0(entrylo0);
 	mtc0_tlbw_hazard();
 	write_c0_entrylo1(entrylo1);
 	mtc0_tlbw_hazard();
 	write_c0_index(kvm_mips_get_commpage_asid(vcpu));
 	mtc0_tlbw_hazard();
 	tlb_write_indexed();
 	mtc0_tlbw_hazard();
 	tlbw_use_hazard();

 	kvm_debug("@ %#lx idx: %2d [entryhi(R): %#lx] entrylo0 (R): 0x%08lx, entrylo1(R): 0x%08lx\n",
 		  vcpu->arch.pc, read_c0_index(), read_c0_entryhi(),
 		  read_c0_entrylo0(), read_c0_entrylo1());

 	/* Restore old ASID */
 	write_c0_entryhi(old_entryhi);
 	mtc0_tlbw_hazard();
 	tlbw_use_hazard();
 	local_irq_restore(flags);

 	return 0;
 }
 EXPORT_SYMBOL(kvm_mips_handle_commpage_tlb_fault);

 int kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu,
 					 struct kvm_mips_tlb *tlb,
 					 unsigned long *hpa0,
 					 unsigned long *hpa1)
 {
 	unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
 	struct kvm *kvm = vcpu->kvm;
 	kvm_pfn_t pfn0, pfn1;

 	if ((tlb->tlb_hi & VPN2_MASK) == 0) {
 		pfn0 = 0;
 		pfn1 = 0;
 	} else {
 		if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0)
 					   >> PAGE_SHIFT) < 0)
 			return -1;

 		if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1)
 					   >> PAGE_SHIFT) < 0)
 			return -1;

 		pfn0 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo0)
 					    >> PAGE_SHIFT];
 		pfn1 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo1)
 					    >> PAGE_SHIFT];
 	}

 	if (hpa0)
 		*hpa0 = pfn0 << PAGE_SHIFT;

 	if (hpa1)
 		*hpa1 = pfn1 << PAGE_SHIFT;

 	/* Get attributes from the Guest TLB */
 	entryhi = (tlb->tlb_hi & VPN2_MASK) | (KVM_GUEST_KERNEL_MODE(vcpu) ?
 					       kvm_mips_get_kernel_asid(vcpu) :
 					       kvm_mips_get_user_asid(vcpu));
 	entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | (0x3 << 3) |
 		   (tlb->tlb_lo0 & MIPS3_PG_D) | (tlb->tlb_lo0 & MIPS3_PG_V);
 	entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) | (0x3 << 3) |
 		   (tlb->tlb_lo1 & MIPS3_PG_D) | (tlb->tlb_lo1 & MIPS3_PG_V);

 	kvm_debug("@ %#lx tlb_lo0: 0x%08lx tlb_lo1: 0x%08lx\n", vcpu->arch.pc,
 		  tlb->tlb_lo0, tlb->tlb_lo1);

 	return kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
 				       tlb->tlb_mask);
 }
 EXPORT_SYMBOL(kvm_mips_handle_mapped_seg_tlb_fault);

 int kvm_mips_guest_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long entryhi)
 {
 	int i;
 	int index = -1;
 	struct kvm_mips_tlb *tlb = vcpu->arch.guest_tlb;

 	for (i = 0; i < KVM_MIPS_GUEST_TLB_SIZE; i++) {
 		if (TLB_HI_VPN2_HIT(tlb[i], entryhi) &&
 		    TLB_HI_ASID_HIT(tlb[i], entryhi)) {
 			index = i;
 			break;
 		}
 	}

 	kvm_debug("%s: entryhi: %#lx, index: %d lo0: %#lx, lo1: %#lx\n",
 		  __func__, entryhi, index, tlb[i].tlb_lo0, tlb[i].tlb_lo1);

 	return index;
 }
 EXPORT_SYMBOL(kvm_mips_guest_tlb_lookup);

 int kvm_mips_host_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long vaddr)
 {
 	unsigned long old_entryhi, flags;
 	int idx;

 	local_irq_save(flags);

 	old_entryhi = read_c0_entryhi();

 	if (KVM_GUEST_KERNEL_MODE(vcpu))
 		write_c0_entryhi((vaddr & VPN2_MASK) |
 				 kvm_mips_get_kernel_asid(vcpu));
 	else {
 		write_c0_entryhi((vaddr & VPN2_MASK) |
 				 kvm_mips_get_user_asid(vcpu));
 	}

 	mtc0_tlbw_hazard();

 	tlb_probe();
 	tlb_probe_hazard();
 	idx = read_c0_index();

 	/* Restore old ASID */
 	write_c0_entryhi(old_entryhi);
 	mtc0_tlbw_hazard();
 	tlbw_use_hazard();

 	local_irq_restore(flags);

 	kvm_debug("Host TLB lookup, %#lx, idx: %2d\n", vaddr, idx);

 	return idx;
 }
 EXPORT_SYMBOL(kvm_mips_host_tlb_lookup);

 int kvm_mips_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va)
 {
 	int idx;
 	unsigned long flags, old_entryhi;

 	local_irq_save(flags);

 	old_entryhi = read_c0_entryhi();

 	write_c0_entryhi((va & VPN2_MASK) | kvm_mips_get_user_asid(vcpu));
 	mtc0_tlbw_hazard();

 	tlb_probe();
 	tlb_probe_hazard();
 	idx = read_c0_index();

 	if (idx >= current_cpu_data.tlbsize)
 		BUG();

 	if (idx > 0) {
 		write_c0_entryhi(UNIQUE_ENTRYHI(idx));
 		mtc0_tlbw_hazard();

 		write_c0_entrylo0(0);
 		mtc0_tlbw_hazard();

 		write_c0_entrylo1(0);
 		mtc0_tlbw_hazard();

 		tlb_write_indexed();
 		mtc0_tlbw_hazard();
 	}

 	write_c0_entryhi(old_entryhi);
 	mtc0_tlbw_hazard();
 	tlbw_use_hazard();

 	local_irq_restore(flags);

 	if (idx > 0)
 		kvm_debug("%s: Invalidated entryhi %#lx @ idx %d\n", __func__,
 			  (va & VPN2_MASK) | kvm_mips_get_user_asid(vcpu), idx);

 	return 0;
 }
 EXPORT_SYMBOL(kvm_mips_host_tlb_inv);

 /* XXXKYMA: Fix Guest USER/KERNEL no longer share the same ASID */
 int kvm_mips_host_tlb_inv_index(struct kvm_vcpu *vcpu, int index)
 {
 	unsigned long flags, old_entryhi;

 	if (index >= current_cpu_data.tlbsize)
 		BUG();

 	local_irq_save(flags);

 	old_entryhi = read_c0_entryhi();

 	write_c0_entryhi(UNIQUE_ENTRYHI(index));
 	mtc0_tlbw_hazard();

 	write_c0_index(index);
 	mtc0_tlbw_hazard();

 	write_c0_entrylo0(0);
 	mtc0_tlbw_hazard();

 	write_c0_entrylo1(0);
 	mtc0_tlbw_hazard();

 	tlb_write_indexed();
 	mtc0_tlbw_hazard();
 	tlbw_use_hazard();

 	write_c0_entryhi(old_entryhi);
 	mtc0_tlbw_hazard();
 	tlbw_use_hazard();

 	local_irq_restore(flags);

 	return 0;
 }

 void kvm_mips_flush_host_tlb(int skip_kseg0)
 {
 	unsigned long flags;
 	unsigned long old_entryhi, entryhi;
 	unsigned long old_pagemask;
 	int entry = 0;
 	int maxentry = current_cpu_data.tlbsize;

 	local_irq_save(flags);

 	old_entryhi = read_c0_entryhi();
 	old_pagemask = read_c0_pagemask();

 	/* Blast 'em all away. */
 	for (entry = 0; entry < maxentry; entry++) {
 		write_c0_index(entry);
 		mtc0_tlbw_hazard();

 		if (skip_kseg0) {
 			tlb_read();
 			tlbw_use_hazard();

 			entryhi = read_c0_entryhi();

 			/* Don't blow away guest kernel entries */
 			if (KVM_GUEST_KSEGX(entryhi) == KVM_GUEST_KSEG0)
 				continue;
 		}

 		/* Make sure all entries differ. */
 		write_c0_entryhi(UNIQUE_ENTRYHI(entry));
 		mtc0_tlbw_hazard();
 		write_c0_entrylo0(0);
 		mtc0_tlbw_hazard();
 		write_c0_entrylo1(0);
 		mtc0_tlbw_hazard();

 		tlb_write_indexed();
 		mtc0_tlbw_hazard();
 	}

 	tlbw_use_hazard();

 	write_c0_entryhi(old_entryhi);
 	write_c0_pagemask(old_pagemask);
 	mtc0_tlbw_hazard();
 	tlbw_use_hazard();

 	local_irq_restore(flags);
 }
 EXPORT_SYMBOL(kvm_mips_flush_host_tlb);

 void kvm_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu,
 			     struct kvm_vcpu *vcpu)
 {
 	unsigned long asid = asid_cache(cpu);

 	asid += ASID_INC;
 	if (!(asid & ASID_MASK)) {
 		if (cpu_has_vtag_icache)
 			flush_icache_all();

 		kvm_local_flush_tlb_all();      /* start new asid cycle */

 		if (!asid)      /* fix version if needed */
 			asid = ASID_FIRST_VERSION;
 	}

 	cpu_context(cpu, mm) = asid_cache(cpu) = asid;
 }

 void kvm_local_flush_tlb_all(void)
 {
 	unsigned long flags;
 	unsigned long old_ctx;
 	int entry = 0;

 	local_irq_save(flags);
 	/* Save old context and create impossible VPN2 value */
 	old_ctx = read_c0_entryhi();
 	write_c0_entrylo0(0);
 	write_c0_entrylo1(0);

 	/* Blast 'em all away. */
 	while (entry < current_cpu_data.tlbsize) {
 		/* Make sure all entries differ. */
 		write_c0_entryhi(UNIQUE_ENTRYHI(entry));
 		write_c0_index(entry);
 		mtc0_tlbw_hazard();
 		tlb_write_indexed();
 		entry++;
 	}
 	tlbw_use_hazard();
 	write_c0_entryhi(old_ctx);
 	mtc0_tlbw_hazard();

 	local_irq_restore(flags);
 }
 EXPORT_SYMBOL(kvm_local_flush_tlb_all);

 /**
  * kvm_mips_migrate_count() - Migrate timer.
  * @vcpu:	Virtual CPU.
  *
  * Migrate CP0_Count hrtimer to the current CPU by cancelling and restarting it
  * if it was running prior to being cancelled.
  *
  * Must be called when the VCPU is migrated to a different CPU to ensure that
  * timer expiry during guest execution interrupts the guest and causes the
  * interrupt to be delivered in a timely manner.
  */
 static void kvm_mips_migrate_count(struct kvm_vcpu *vcpu)
 {
 	if (hrtimer_cancel(&vcpu->arch.comparecount_timer))
 		hrtimer_restart(&vcpu->arch.comparecount_timer);
 }

 /* Restore ASID once we are scheduled back after preemption */
 void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
 {
 	unsigned long flags;
 	int newasid = 0;

 	kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu);

 	/* Alocate new kernel and user ASIDs if needed */

 	local_irq_save(flags);

 	if (((vcpu->arch.
 	      guest_kernel_asid[cpu] ^ asid_cache(cpu)) & ASID_VERSION_MASK)) {
 		kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm, cpu, vcpu);
 		vcpu->arch.guest_kernel_asid[cpu] =
 		    vcpu->arch.guest_kernel_mm.context.asid[cpu];
 		kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu, vcpu);
 		vcpu->arch.guest_user_asid[cpu] =
 		    vcpu->arch.guest_user_mm.context.asid[cpu];
 		newasid++;

 		kvm_debug("[%d]: cpu_context: %#lx\n", cpu,
 			  cpu_context(cpu, current->mm));
 		kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#x\n",
 			  cpu, vcpu->arch.guest_kernel_asid[cpu]);
 		kvm_debug("[%d]: Allocated new ASID for Guest User: %#x\n", cpu,
 			  vcpu->arch.guest_user_asid[cpu]);
 	}

 	if (vcpu->arch.last_sched_cpu != cpu) {
 		kvm_debug("[%d->%d]KVM VCPU[%d] switch\n",
 			  vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id);
 		/*
 		 * Migrate the timer interrupt to the current CPU so that it
 		 * always interrupts the guest and synchronously triggers a
 		 * guest timer interrupt.
 		 */
 		kvm_mips_migrate_count(vcpu);
 	}

 	if (!newasid) {
 		/*
 		 * If we preempted while the guest was executing, then reload
 		 * the pre-empted ASID
 		 */
 		if (current->flags & PF_VCPU) {
 			write_c0_entryhi(vcpu->arch.
 					 preempt_entryhi & ASID_MASK);
 			ehb();
 		}
 	} else {
 		/* New ASIDs were allocated for the VM */

 		/*
 		 * Were we in guest context? If so then the pre-empted ASID is
 		 * no longer valid, we need to set it to what it should be based
 		 * on the mode of the Guest (Kernel/User)
 		 */
 		if (current->flags & PF_VCPU) {
 			if (KVM_GUEST_KERNEL_MODE(vcpu))
 				write_c0_entryhi(vcpu->arch.
 						 guest_kernel_asid[cpu] &
 						 ASID_MASK);
 			else
 				write_c0_entryhi(vcpu->arch.
 						 guest_user_asid[cpu] &
 						 ASID_MASK);
 			ehb();
 		}
 	}

 	/* restore guest state to registers */
 	kvm_mips_callbacks->vcpu_set_regs(vcpu);

 	local_irq_restore(flags);

 }
 EXPORT_SYMBOL(kvm_arch_vcpu_load);

 /* ASID can change if another task is scheduled during preemption */
 void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
 {
 	unsigned long flags;
 	uint32_t cpu;

 	local_irq_save(flags);

 	cpu = smp_processor_id();

 	vcpu->arch.preempt_entryhi = read_c0_entryhi();
 	vcpu->arch.last_sched_cpu = cpu;

 	/* save guest state in registers */
 	kvm_mips_callbacks->vcpu_get_regs(vcpu);

 	if (((cpu_context(cpu, current->mm) ^ asid_cache(cpu)) &
 	     ASID_VERSION_MASK)) {
 		kvm_debug("%s: Dropping MMU Context:  %#lx\n", __func__,
 			  cpu_context(cpu, current->mm));
 		drop_mmu_context(current->mm, cpu);
 	}
 	write_c0_entryhi(cpu_asid(cpu, current->mm));
 	ehb();

 	local_irq_restore(flags);
 }
 EXPORT_SYMBOL(kvm_arch_vcpu_put);

 uint32_t kvm_get_inst(uint32_t *opc, struct kvm_vcpu *vcpu)
 {
 	struct mips_coproc *cop0 = vcpu->arch.cop0;
 	unsigned long paddr, flags, vpn2, asid;
 	uint32_t inst;
 	int index;

 	if (KVM_GUEST_KSEGX((unsigned long) opc) < KVM_GUEST_KSEG0 ||
 	    KVM_GUEST_KSEGX((unsigned long) opc) == KVM_GUEST_KSEG23) {
 		local_irq_save(flags);
 		index = kvm_mips_host_tlb_lookup(vcpu, (unsigned long) opc);
 		if (index >= 0) {
 			inst = *(opc);
 		} else {
 			vpn2 = (unsigned long) opc & VPN2_MASK;
 			asid = kvm_read_c0_guest_entryhi(cop0) & ASID_MASK;
 			index = kvm_mips_guest_tlb_lookup(vcpu, vpn2 | asid);
 			if (index < 0) {
 				kvm_err("%s: get_user_failed for %p, vcpu: %p, ASID: %#lx\n",
 					__func__, opc, vcpu, read_c0_entryhi());
 				kvm_mips_dump_host_tlbs();
 				local_irq_restore(flags);
 				return KVM_INVALID_INST;
 			}
 			kvm_mips_handle_mapped_seg_tlb_fault(vcpu,
 							     &vcpu->arch.
 							     guest_tlb[index],
 							     NULL, NULL);
 			inst = *(opc);
 		}
 		local_irq_restore(flags);
 	} else if (KVM_GUEST_KSEGX(opc) == KVM_GUEST_KSEG0) {
 		paddr =
 		    kvm_mips_translate_guest_kseg0_to_hpa(vcpu,
 							  (unsigned long) opc);
 		inst = *(uint32_t *) CKSEG0ADDR(paddr);
 	} else {
 		kvm_err("%s: illegal address: %p\n", __func__, opc);
 		return KVM_INVALID_INST;
 	}

 	return inst;
 }
 EXPORT_SYMBOL(kvm_get_inst);
	/*
	* This file is subject to the terms and conditions of the GNU General Public
	* License. See the file "COPYING" in the main directory of this archive
	* for more details.
	*
	* KVM/MIPS TLB handling, this file is part of the Linux host kernel so that
	* TLB handlers run from KSEG0
	*
	* Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
	* Authors: Sanjay Lal <sanjayl@kymasys.com>
	*/

	#include <linux/sched.h>
	#include <linux/smp.h>
	#include <linux/mm.h>
	#include <linux/delay.h>
	#include <linux/module.h>
	#include <linux/kvm_host.h>
	#include <linux/srcu.h>

	#include <asm/cpu.h>
	#include <asm/bootinfo.h>
	#include <asm/mmu_context.h>
	#include <asm/pgtable.h>
	#include <asm/cacheflush.h>
	#include <asm/tlb.h>

	#undef CONFIG_MIPS_MT
	#include <asm/r4kcache.h>
	#define CONFIG_MIPS_MT

	#define KVM_GUEST_PC_TLB 0
	#define KVM_GUEST_SP_TLB 1

	#define PRIx64 "llx"

	atomic_t kvm_mips_instance;
	EXPORT_SYMBOL(kvm_mips_instance);

	/* These function pointers are initialized once the KVM module is loaded */
	kvm_pfn_t (kvm_mips_gfn_to_pfn)(struct kvm kvm, gfn_t gfn);
	EXPORT_SYMBOL(kvm_mips_gfn_to_pfn);

	void (*kvm_mips_release_pfn_clean)(kvm_pfn_t pfn);
	EXPORT_SYMBOL(kvm_mips_release_pfn_clean);

	bool (*kvm_mips_is_error_pfn)(kvm_pfn_t pfn);
	EXPORT_SYMBOL(kvm_mips_is_error_pfn);

	uint32_t kvm_mips_get_kernel_asid(struct kvm_vcpu *vcpu)
	{
	return vcpu->arch.guest_kernel_asid[smp_processor_id()] & ASID_MASK;
	}

	uint32_t kvm_mips_get_user_asid(struct kvm_vcpu *vcpu)
	{
	return vcpu->arch.guest_user_asid[smp_processor_id()] & ASID_MASK;
	}

	inline uint32_t kvm_mips_get_commpage_asid(struct kvm_vcpu *vcpu)
	{
	return vcpu->kvm->arch.commpage_tlb;
	}

	/* Structure defining an tlb entry data set. */

	void kvm_mips_dump_host_tlbs(void)
	{
	unsigned long old_entryhi;
	unsigned long old_pagemask;
	struct kvm_mips_tlb tlb;
	unsigned long flags;
	int i;

	local_irq_save(flags);

	old_entryhi = read_c0_entryhi();
	old_pagemask = read_c0_pagemask();

	kvm_info("HOST TLBs:\n");
	kvm_info("ASID: %#lx\n", read_c0_entryhi() & ASID_MASK);

	for (i = 0; i < current_cpu_data.tlbsize; i++) {
	write_c0_index(i);
	mtc0_tlbw_hazard();

	tlb_read();
	tlbw_use_hazard();

	tlb.tlb_hi = read_c0_entryhi();
	tlb.tlb_lo0 = read_c0_entrylo0();
	tlb.tlb_lo1 = read_c0_entrylo1();
	tlb.tlb_mask = read_c0_pagemask();

	kvm_info("TLB%c%3d Hi 0x%08lx ",
	(tlb.tlb_lo0 \| tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*',
	i, tlb.tlb_hi);
	kvm_info("Lo0=0x%09" PRIx64 " %c%c attr %lx ",
	(uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo0),
	(tlb.tlb_lo0 & MIPS3_PG_D) ? 'D' : ' ',
	(tlb.tlb_lo0 & MIPS3_PG_G) ? 'G' : ' ',
	(tlb.tlb_lo0 >> 3) & 7);
	kvm_info("Lo1=0x%09" PRIx64 " %c%c attr %lx sz=%lx\n",
	(uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo1),
	(tlb.tlb_lo1 & MIPS3_PG_D) ? 'D' : ' ',
	(tlb.tlb_lo1 & MIPS3_PG_G) ? 'G' : ' ',
	(tlb.tlb_lo1 >> 3) & 7, tlb.tlb_mask);
	}
	write_c0_entryhi(old_entryhi);
	write_c0_pagemask(old_pagemask);
	mtc0_tlbw_hazard();
	local_irq_restore(flags);
	}
	EXPORT_SYMBOL(kvm_mips_dump_host_tlbs);

	void kvm_mips_dump_guest_tlbs(struct kvm_vcpu *vcpu)
	{
	struct mips_coproc *cop0 = vcpu->arch.cop0;
	struct kvm_mips_tlb tlb;
	int i;

	kvm_info("Guest TLBs:\n");
	kvm_info("Guest EntryHi: %#lx\n", kvm_read_c0_guest_entryhi(cop0));

	for (i = 0; i < KVM_MIPS_GUEST_TLB_SIZE; i++) {
	tlb = vcpu->arch.guest_tlb[i];
	kvm_info("TLB%c%3d Hi 0x%08lx ",
	(tlb.tlb_lo0 \| tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*',
	i, tlb.tlb_hi);
	kvm_info("Lo0=0x%09" PRIx64 " %c%c attr %lx ",
	(uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo0),
	(tlb.tlb_lo0 & MIPS3_PG_D) ? 'D' : ' ',
	(tlb.tlb_lo0 & MIPS3_PG_G) ? 'G' : ' ',
	(tlb.tlb_lo0 >> 3) & 7);
	kvm_info("Lo1=0x%09" PRIx64 " %c%c attr %lx sz=%lx\n",
	(uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo1),
	(tlb.tlb_lo1 & MIPS3_PG_D) ? 'D' : ' ',
	(tlb.tlb_lo1 & MIPS3_PG_G) ? 'G' : ' ',
	(tlb.tlb_lo1 >> 3) & 7, tlb.tlb_mask);
	}
	}
	EXPORT_SYMBOL(kvm_mips_dump_guest_tlbs);

	static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn)
	{
	int srcu_idx, err = 0;
	kvm_pfn_t pfn;

	if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE)
	return 0;

	srcu_idx = srcu_read_lock(&kvm->srcu);
	pfn = kvm_mips_gfn_to_pfn(kvm, gfn);

	if (kvm_mips_is_error_pfn(pfn)) {
	kvm_err("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn);
	err = -EFAULT;
	goto out;
	}

	kvm->arch.guest_pmap[gfn] = pfn;
	out:
	srcu_read_unlock(&kvm->srcu, srcu_idx);
	return err;
	}

	/* Translate guest KSEG0 addresses to Host PA */
	unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu,
	unsigned long gva)
	{
	gfn_t gfn;
	uint32_t offset = gva & ~PAGE_MASK;
	struct kvm *kvm = vcpu->kvm;

	if (KVM_GUEST_KSEGX(gva) != KVM_GUEST_KSEG0) {
	kvm_err("%s/%p: Invalid gva: %#lx\n", __func__,
	__builtin_return_address(0), gva);
	return KVM_INVALID_PAGE;
	}

	gfn = (KVM_GUEST_CPHYSADDR(gva) >> PAGE_SHIFT);

	if (gfn >= kvm->arch.guest_pmap_npages) {
	kvm_err("%s: Invalid gfn: %#llx, GVA: %#lx\n", __func__, gfn,
	gva);
	return KVM_INVALID_PAGE;
	}

	if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
	return KVM_INVALID_ADDR;

	return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset;
	}
	EXPORT_SYMBOL(kvm_mips_translate_guest_kseg0_to_hpa);

	/* XXXKYMA: Must be called with interrupts disabled */
	/* set flush_dcache_mask == 0 if no dcache flush required */
	int kvm_mips_host_tlb_write(struct kvm_vcpu *vcpu, unsigned long entryhi,
	unsigned long entrylo0, unsigned long entrylo1,
	int flush_dcache_mask)
	{
	unsigned long flags;
	unsigned long old_entryhi;
	int idx;

	local_irq_save(flags);

	old_entryhi = read_c0_entryhi();
	write_c0_entryhi(entryhi);
	mtc0_tlbw_hazard();

	tlb_probe();
	tlb_probe_hazard();
	idx = read_c0_index();

	if (idx > current_cpu_data.tlbsize) {
	kvm_err("%s: Invalid Index: %d\n", __func__, idx);
	kvm_mips_dump_host_tlbs();
	local_irq_restore(flags);
	return -1;
	}

	write_c0_entrylo0(entrylo0);
	write_c0_entrylo1(entrylo1);
	mtc0_tlbw_hazard();

	if (idx < 0)
	tlb_write_random();
	else
	tlb_write_indexed();
	tlbw_use_hazard();

	kvm_debug("@ %#lx idx: %2d [entryhi(R): %#lx] entrylo0(R): 0x%08lx, entrylo1(R): 0x%08lx\n",
	vcpu->arch.pc, idx, read_c0_entryhi(),
	read_c0_entrylo0(), read_c0_entrylo1());

	/* Flush D-cache */
	if (flush_dcache_mask) {
	if (entrylo0 & MIPS3_PG_V) {
	++vcpu->stat.flush_dcache_exits;
	flush_data_cache_page((entryhi & VPN2_MASK) &
	~flush_dcache_mask);
	}
	if (entrylo1 & MIPS3_PG_V) {
	++vcpu->stat.flush_dcache_exits;
	flush_data_cache_page(((entryhi & VPN2_MASK) &
	~flush_dcache_mask) \|
	(0x1 << PAGE_SHIFT));
	}
	}

	/* Restore old ASID */
	write_c0_entryhi(old_entryhi);
	mtc0_tlbw_hazard();
	tlbw_use_hazard();
	local_irq_restore(flags);
	return 0;
	}

	/* XXXKYMA: Must be called with interrupts disabled */
	int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr,
	struct kvm_vcpu *vcpu)
	{
	gfn_t gfn;
	kvm_pfn_t pfn0, pfn1;
	unsigned long vaddr = 0;
	unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
	int even;
	struct kvm *kvm = vcpu->kvm;
	const int flush_dcache_mask = 0;

	if (KVM_GUEST_KSEGX(badvaddr) != KVM_GUEST_KSEG0) {
	kvm_err("%s: Invalid BadVaddr: %#lx\n", __func__, badvaddr);
	kvm_mips_dump_host_tlbs();
	return -1;
	}

	gfn = (KVM_GUEST_CPHYSADDR(badvaddr) >> PAGE_SHIFT);
	if (gfn >= kvm->arch.guest_pmap_npages) {
	kvm_err("%s: Invalid gfn: %#llx, BadVaddr: %#lx\n", __func__,
	gfn, badvaddr);
	kvm_mips_dump_host_tlbs();
	return -1;
	}
	even = !(gfn & 0x1);
	vaddr = badvaddr & (PAGE_MASK << 1);

	if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
	return -1;

	if (kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1) < 0)
	return -1;

	if (even) {
	pfn0 = kvm->arch.guest_pmap[gfn];
	pfn1 = kvm->arch.guest_pmap[gfn ^ 0x1];
	} else {
	pfn0 = kvm->arch.guest_pmap[gfn ^ 0x1];
	pfn1 = kvm->arch.guest_pmap[gfn];
	}

	entryhi = (vaddr \| kvm_mips_get_kernel_asid(vcpu));
	entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) \| (0x3 << 3) \|
	(1 << 2) \| (0x1 << 1);
	entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) \| (0x3 << 3) \|
	(1 << 2) \| (0x1 << 1);

	return kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
	flush_dcache_mask);
	}
	EXPORT_SYMBOL(kvm_mips_handle_kseg0_tlb_fault);

	int kvm_mips_handle_commpage_tlb_fault(unsigned long badvaddr,
	struct kvm_vcpu *vcpu)
	{
	kvm_pfn_t pfn0, pfn1;
	unsigned long flags, old_entryhi = 0, vaddr = 0;
	unsigned long entrylo0 = 0, entrylo1 = 0;

	pfn0 = CPHYSADDR(vcpu->arch.kseg0_commpage) >> PAGE_SHIFT;
	pfn1 = 0;
	entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) \| (0x3 << 3) \|
	(1 << 2) \| (0x1 << 1);
	entrylo1 = 0;

	local_irq_save(flags);

	old_entryhi = read_c0_entryhi();
	vaddr = badvaddr & (PAGE_MASK << 1);
	write_c0_entryhi(vaddr \| kvm_mips_get_kernel_asid(vcpu));
	mtc0_tlbw_hazard();
	write_c0_entrylo0(entrylo0);
	mtc0_tlbw_hazard();
	write_c0_entrylo1(entrylo1);
	mtc0_tlbw_hazard();
	write_c0_index(kvm_mips_get_commpage_asid(vcpu));
	mtc0_tlbw_hazard();
	tlb_write_indexed();
	mtc0_tlbw_hazard();
	tlbw_use_hazard();

	kvm_debug("@ %#lx idx: %2d [entryhi(R): %#lx] entrylo0 (R): 0x%08lx, entrylo1(R): 0x%08lx\n",
	vcpu->arch.pc, read_c0_index(), read_c0_entryhi(),
	read_c0_entrylo0(), read_c0_entrylo1());

	/* Restore old ASID */
	write_c0_entryhi(old_entryhi);
	mtc0_tlbw_hazard();
	tlbw_use_hazard();
	local_irq_restore(flags);

	return 0;
	}
	EXPORT_SYMBOL(kvm_mips_handle_commpage_tlb_fault);

	int kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu,
	struct kvm_mips_tlb *tlb,
	unsigned long *hpa0,
	unsigned long *hpa1)
	{
	unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
	struct kvm *kvm = vcpu->kvm;
	kvm_pfn_t pfn0, pfn1;

	if ((tlb->tlb_hi & VPN2_MASK) == 0) {
	pfn0 = 0;
	pfn1 = 0;
	} else {
	if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0)
	>> PAGE_SHIFT) < 0)
	return -1;

	if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1)
	>> PAGE_SHIFT) < 0)
	return -1;

	pfn0 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo0)
	>> PAGE_SHIFT];
	pfn1 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo1)
	>> PAGE_SHIFT];
	}

	if (hpa0)
	*hpa0 = pfn0 << PAGE_SHIFT;

	if (hpa1)
	*hpa1 = pfn1 << PAGE_SHIFT;

	/* Get attributes from the Guest TLB */
	entryhi = (tlb->tlb_hi & VPN2_MASK) \| (KVM_GUEST_KERNEL_MODE(vcpu) ?
	kvm_mips_get_kernel_asid(vcpu) :
	kvm_mips_get_user_asid(vcpu));
	entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) \| (0x3 << 3) \|
	(tlb->tlb_lo0 & MIPS3_PG_D) \| (tlb->tlb_lo0 & MIPS3_PG_V);
	entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) \| (0x3 << 3) \|
	(tlb->tlb_lo1 & MIPS3_PG_D) \| (tlb->tlb_lo1 & MIPS3_PG_V);

	kvm_debug("@ %#lx tlb_lo0: 0x%08lx tlb_lo1: 0x%08lx\n", vcpu->arch.pc,
	tlb->tlb_lo0, tlb->tlb_lo1);

	return kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
	tlb->tlb_mask);
	}
	EXPORT_SYMBOL(kvm_mips_handle_mapped_seg_tlb_fault);

	int kvm_mips_guest_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long entryhi)
	{
	int i;
	int index = -1;
	struct kvm_mips_tlb *tlb = vcpu->arch.guest_tlb;

	for (i = 0; i < KVM_MIPS_GUEST_TLB_SIZE; i++) {
	if (TLB_HI_VPN2_HIT(tlb[i], entryhi) &&
	TLB_HI_ASID_HIT(tlb[i], entryhi)) {
	index = i;
	break;
	}
	}

	kvm_debug("%s: entryhi: %#lx, index: %d lo0: %#lx, lo1: %#lx\n",
	__func__, entryhi, index, tlb[i].tlb_lo0, tlb[i].tlb_lo1);

	return index;
	}
	EXPORT_SYMBOL(kvm_mips_guest_tlb_lookup);

	int kvm_mips_host_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long vaddr)
	{
	unsigned long old_entryhi, flags;
	int idx;

	local_irq_save(flags);

	old_entryhi = read_c0_entryhi();

	if (KVM_GUEST_KERNEL_MODE(vcpu))
	write_c0_entryhi((vaddr & VPN2_MASK) \|
	kvm_mips_get_kernel_asid(vcpu));
	else {
	write_c0_entryhi((vaddr & VPN2_MASK) \|
	kvm_mips_get_user_asid(vcpu));
	}

	mtc0_tlbw_hazard();

	tlb_probe();
	tlb_probe_hazard();
	idx = read_c0_index();

	/* Restore old ASID */
	write_c0_entryhi(old_entryhi);
	mtc0_tlbw_hazard();
	tlbw_use_hazard();

	local_irq_restore(flags);

	kvm_debug("Host TLB lookup, %#lx, idx: %2d\n", vaddr, idx);

	return idx;
	}
	EXPORT_SYMBOL(kvm_mips_host_tlb_lookup);

	int kvm_mips_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va)
	{
	int idx;
	unsigned long flags, old_entryhi;

	local_irq_save(flags);

	old_entryhi = read_c0_entryhi();

	write_c0_entryhi((va & VPN2_MASK) \| kvm_mips_get_user_asid(vcpu));
	mtc0_tlbw_hazard();

	tlb_probe();
	tlb_probe_hazard();
	idx = read_c0_index();

	if (idx >= current_cpu_data.tlbsize)
	BUG();

	if (idx > 0) {
	write_c0_entryhi(UNIQUE_ENTRYHI(idx));
	mtc0_tlbw_hazard();

	write_c0_entrylo0(0);
	mtc0_tlbw_hazard();

	write_c0_entrylo1(0);
	mtc0_tlbw_hazard();

	tlb_write_indexed();
	mtc0_tlbw_hazard();
	}

	write_c0_entryhi(old_entryhi);
	mtc0_tlbw_hazard();
	tlbw_use_hazard();

	local_irq_restore(flags);

	if (idx > 0)
	kvm_debug("%s: Invalidated entryhi %#lx @ idx %d\n", __func__,
	(va & VPN2_MASK) \| kvm_mips_get_user_asid(vcpu), idx);

	return 0;
	}
	EXPORT_SYMBOL(kvm_mips_host_tlb_inv);

	/* XXXKYMA: Fix Guest USER/KERNEL no longer share the same ASID */
	int kvm_mips_host_tlb_inv_index(struct kvm_vcpu *vcpu, int index)
	{
	unsigned long flags, old_entryhi;

	if (index >= current_cpu_data.tlbsize)
	BUG();

	local_irq_save(flags);

	old_entryhi = read_c0_entryhi();

	write_c0_entryhi(UNIQUE_ENTRYHI(index));
	mtc0_tlbw_hazard();

	write_c0_index(index);
	mtc0_tlbw_hazard();

	write_c0_entrylo0(0);
	mtc0_tlbw_hazard();

	write_c0_entrylo1(0);
	mtc0_tlbw_hazard();

	tlb_write_indexed();
	mtc0_tlbw_hazard();
	tlbw_use_hazard();

	write_c0_entryhi(old_entryhi);
	mtc0_tlbw_hazard();
	tlbw_use_hazard();

	local_irq_restore(flags);

	return 0;
	}

	void kvm_mips_flush_host_tlb(int skip_kseg0)
	{
	unsigned long flags;
	unsigned long old_entryhi, entryhi;
	unsigned long old_pagemask;
	int entry = 0;
	int maxentry = current_cpu_data.tlbsize;

	local_irq_save(flags);

	old_entryhi = read_c0_entryhi();
	old_pagemask = read_c0_pagemask();

	/* Blast 'em all away. */
	for (entry = 0; entry < maxentry; entry++) {
	write_c0_index(entry);
	mtc0_tlbw_hazard();

	if (skip_kseg0) {
	tlb_read();
	tlbw_use_hazard();

	entryhi = read_c0_entryhi();

	/* Don't blow away guest kernel entries */
	if (KVM_GUEST_KSEGX(entryhi) == KVM_GUEST_KSEG0)
	continue;
	}

	/* Make sure all entries differ. */
	write_c0_entryhi(UNIQUE_ENTRYHI(entry));
	mtc0_tlbw_hazard();
	write_c0_entrylo0(0);
	mtc0_tlbw_hazard();
	write_c0_entrylo1(0);
	mtc0_tlbw_hazard();

	tlb_write_indexed();
	mtc0_tlbw_hazard();
	}

	tlbw_use_hazard();

	write_c0_entryhi(old_entryhi);
	write_c0_pagemask(old_pagemask);
	mtc0_tlbw_hazard();
	tlbw_use_hazard();

	local_irq_restore(flags);
	}
	EXPORT_SYMBOL(kvm_mips_flush_host_tlb);

	void kvm_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu,
	struct kvm_vcpu *vcpu)
	{
	unsigned long asid = asid_cache(cpu);

	asid += ASID_INC;
	if (!(asid & ASID_MASK)) {
	if (cpu_has_vtag_icache)
	flush_icache_all();

	kvm_local_flush_tlb_all(); /* start new asid cycle */

	if (!asid) /* fix version if needed */
	asid = ASID_FIRST_VERSION;
	}

	cpu_context(cpu, mm) = asid_cache(cpu) = asid;
	}

	void kvm_local_flush_tlb_all(void)
	{
	unsigned long flags;
	unsigned long old_ctx;
	int entry = 0;

	local_irq_save(flags);
	/* Save old context and create impossible VPN2 value */
	old_ctx = read_c0_entryhi();
	write_c0_entrylo0(0);
	write_c0_entrylo1(0);

	/* Blast 'em all away. */
	while (entry < current_cpu_data.tlbsize) {
	/* Make sure all entries differ. */
	write_c0_entryhi(UNIQUE_ENTRYHI(entry));
	write_c0_index(entry);
	mtc0_tlbw_hazard();
	tlb_write_indexed();
	entry++;
	}
	tlbw_use_hazard();
	write_c0_entryhi(old_ctx);
	mtc0_tlbw_hazard();

	local_irq_restore(flags);
	}
	EXPORT_SYMBOL(kvm_local_flush_tlb_all);

	/**
	* kvm_mips_migrate_count() - Migrate timer.
	* @vcpu: Virtual CPU.
	*
	* Migrate CP0_Count hrtimer to the current CPU by cancelling and restarting it
	* if it was running prior to being cancelled.
	*
	* Must be called when the VCPU is migrated to a different CPU to ensure that
	* timer expiry during guest execution interrupts the guest and causes the
	* interrupt to be delivered in a timely manner.
	*/
	static void kvm_mips_migrate_count(struct kvm_vcpu *vcpu)
	{
	if (hrtimer_cancel(&vcpu->arch.comparecount_timer))
	hrtimer_restart(&vcpu->arch.comparecount_timer);
	}

	/* Restore ASID once we are scheduled back after preemption */
	void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
	{
	unsigned long flags;
	int newasid = 0;

	kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu);

	/* Alocate new kernel and user ASIDs if needed */

	local_irq_save(flags);

	if (((vcpu->arch.
	guest_kernel_asid[cpu] ^ asid_cache(cpu)) & ASID_VERSION_MASK)) {
	kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm, cpu, vcpu);
	vcpu->arch.guest_kernel_asid[cpu] =
	vcpu->arch.guest_kernel_mm.context.asid[cpu];
	kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu, vcpu);
	vcpu->arch.guest_user_asid[cpu] =
	vcpu->arch.guest_user_mm.context.asid[cpu];
	newasid++;

	kvm_debug("[%d]: cpu_context: %#lx\n", cpu,
	cpu_context(cpu, current->mm));
	kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#x\n",
	cpu, vcpu->arch.guest_kernel_asid[cpu]);
	kvm_debug("[%d]: Allocated new ASID for Guest User: %#x\n", cpu,
	vcpu->arch.guest_user_asid[cpu]);
	}

	if (vcpu->arch.last_sched_cpu != cpu) {
	kvm_debug("[%d->%d]KVM VCPU[%d] switch\n",
	vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id);
	/*
	* Migrate the timer interrupt to the current CPU so that it
	* always interrupts the guest and synchronously triggers a
	* guest timer interrupt.
	*/
	kvm_mips_migrate_count(vcpu);
	}

	if (!newasid) {
	/*
	* If we preempted while the guest was executing, then reload
	* the pre-empted ASID
	*/
	if (current->flags & PF_VCPU) {
	write_c0_entryhi(vcpu->arch.
	preempt_entryhi & ASID_MASK);
	ehb();
	}
	} else {
	/* New ASIDs were allocated for the VM */

	/*
	* Were we in guest context? If so then the pre-empted ASID is
	* no longer valid, we need to set it to what it should be based
	* on the mode of the Guest (Kernel/User)
	*/
	if (current->flags & PF_VCPU) {
	if (KVM_GUEST_KERNEL_MODE(vcpu))
	write_c0_entryhi(vcpu->arch.
	guest_kernel_asid[cpu] &
	ASID_MASK);
	else
	write_c0_entryhi(vcpu->arch.
	guest_user_asid[cpu] &
	ASID_MASK);
	ehb();
	}
	}

	/* restore guest state to registers */
	kvm_mips_callbacks->vcpu_set_regs(vcpu);

	local_irq_restore(flags);

	}
	EXPORT_SYMBOL(kvm_arch_vcpu_load);

	/* ASID can change if another task is scheduled during preemption */
	void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
	{
	unsigned long flags;
	uint32_t cpu;

	local_irq_save(flags);

	cpu = smp_processor_id();

	vcpu->arch.preempt_entryhi = read_c0_entryhi();
	vcpu->arch.last_sched_cpu = cpu;

	/* save guest state in registers */
	kvm_mips_callbacks->vcpu_get_regs(vcpu);

	if (((cpu_context(cpu, current->mm) ^ asid_cache(cpu)) &
	ASID_VERSION_MASK)) {
	kvm_debug("%s: Dropping MMU Context: %#lx\n", __func__,
	cpu_context(cpu, current->mm));
	drop_mmu_context(current->mm, cpu);
	}
	write_c0_entryhi(cpu_asid(cpu, current->mm));
	ehb();

	local_irq_restore(flags);
	}
	EXPORT_SYMBOL(kvm_arch_vcpu_put);

	uint32_t kvm_get_inst(uint32_t opc, struct kvm_vcpu vcpu)
	{
	struct mips_coproc *cop0 = vcpu->arch.cop0;
	unsigned long paddr, flags, vpn2, asid;
	uint32_t inst;
	int index;

	if (KVM_GUEST_KSEGX((unsigned long) opc) < KVM_GUEST_KSEG0 \|\|
	KVM_GUEST_KSEGX((unsigned long) opc) == KVM_GUEST_KSEG23) {
	local_irq_save(flags);
	index = kvm_mips_host_tlb_lookup(vcpu, (unsigned long) opc);
	if (index >= 0) {
	inst = *(opc);
	} else {
	vpn2 = (unsigned long) opc & VPN2_MASK;
	asid = kvm_read_c0_guest_entryhi(cop0) & ASID_MASK;
	index = kvm_mips_guest_tlb_lookup(vcpu, vpn2 \| asid);
	if (index < 0) {
	kvm_err("%s: get_user_failed for %p, vcpu: %p, ASID: %#lx\n",
	__func__, opc, vcpu, read_c0_entryhi());
	kvm_mips_dump_host_tlbs();
	local_irq_restore(flags);
	return KVM_INVALID_INST;
	}
	kvm_mips_handle_mapped_seg_tlb_fault(vcpu,
	&vcpu->arch.
	guest_tlb[index],
	NULL, NULL);
	inst = *(opc);
	}
	local_irq_restore(flags);
	} else if (KVM_GUEST_KSEGX(opc) == KVM_GUEST_KSEG0) {
	paddr =
	kvm_mips_translate_guest_kseg0_to_hpa(vcpu,
	(unsigned long) opc);
	inst = (uint32_t ) CKSEG0ADDR(paddr);
	} else {
	kvm_err("%s: illegal address: %p\n", __func__, opc);
	return KVM_INVALID_INST;
	}

	return inst;
	}
	EXPORT_SYMBOL(kvm_get_inst);