1 files changed, 932 insertions, 0 deletions

diff --git a/arch/mips/kvm/kvm_tlb.c b/arch/mips/kvm/kvm_tlb.c
new file mode 100644
index 000000000000..e3f0d9b8b6c5
--- /dev/null
+++ b/arch/mips/kvm/kvm_tlb.c
@@ -0,0 +1,932 @@
+/*
+* 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/init.h>
+#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 <asm/cpu.h>
+#include <asm/bootinfo.h>
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+#include <asm/cacheflush.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"
+
+/* Use VZ EntryHi.EHINV to invalidate TLB entries */
+#define UNIQUE_ENTRYHI(idx) (CKSEG0 + ((idx) << (PAGE_SHIFT + 1)))
+
+atomic_t kvm_mips_instance;
+EXPORT_SYMBOL(kvm_mips_instance);
+
+/* These function pointers are initialized once the KVM module is loaded */
+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) (pfn_t pfn);
+EXPORT_SYMBOL(kvm_mips_release_pfn_clean);
+
+bool(*kvm_mips_is_error_pfn) (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();
+
+	printk("HOST TLBs:\n");
+	printk("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();
+
+		printk("TLB%c%3d Hi 0x%08lx ",
+		       (tlb.tlb_lo0 | tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*',
+		       i, tlb.tlb_hi);
+		printk("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);
+		printk("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);
+}
+
+void kvm_mips_dump_guest_tlbs(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = vcpu->arch.cop0;
+	struct kvm_mips_tlb tlb;
+	int i;
+
+	printk("Guest TLBs:\n");
+	printk("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];
+		printk("TLB%c%3d Hi 0x%08lx ",
+		       (tlb.tlb_lo0 | tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*',
+		       i, tlb.tlb_hi);
+		printk("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);
+		printk("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);
+	}
+}
+
+void kvm_mips_dump_shadow_tlbs(struct kvm_vcpu *vcpu)
+{
+	int i;
+	volatile struct kvm_mips_tlb tlb;
+
+	printk("Shadow TLBs:\n");
+	for (i = 0; i < KVM_MIPS_GUEST_TLB_SIZE; i++) {
+		tlb = vcpu->arch.shadow_tlb[smp_processor_id()][i];
+		printk("TLB%c%3d Hi 0x%08lx ",
+		       (tlb.tlb_lo0 | tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*',
+		       i, tlb.tlb_hi);
+		printk("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);
+		printk("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);
+	}
+}
+
+static void kvm_mips_map_page(struct kvm *kvm, gfn_t gfn)
+{
+	pfn_t pfn;
+
+	if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE)
+		return;
+
+	pfn = kvm_mips_gfn_to_pfn(kvm, gfn);
+
+	if (kvm_mips_is_error_pfn(pfn)) {
+		panic("Couldn't get pfn for gfn %#" PRIx64 "!\n", gfn);
+	}
+
+	kvm->arch.guest_pmap[gfn] = pfn;
+	return;
+}
+
+/* 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;
+	}
+	kvm_mips_map_page(vcpu->kvm, gfn);
+	return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset;
+}
+
+/* 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;
+	volatile 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();
+		return -1;
+	}
+
+	if (idx < 0) {
+		idx = read_c0_random() % current_cpu_data.tlbsize;
+		write_c0_index(idx);
+		mtc0_tlbw_hazard();
+	}
+	write_c0_entrylo0(entrylo0);
+	write_c0_entrylo1(entrylo1);
+	mtc0_tlbw_hazard();
+
+	tlb_write_indexed();
+	tlbw_use_hazard();
+
+#ifdef DEBUG
+	if (debug) {
+		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());
+	}
+#endif
+
+	/* 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;
+	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);
+
+	kvm_mips_map_page(vcpu->kvm, gfn);
+	kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1);
+
+	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);
+}
+
+int kvm_mips_handle_commpage_tlb_fault(unsigned long badvaddr,
+	struct kvm_vcpu *vcpu)
+{
+	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();
+
+#ifdef DEBUG
+	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());
+#endif
+
+	/* Restore old ASID */
+	write_c0_entryhi(old_entryhi);
+	mtc0_tlbw_hazard();
+	tlbw_use_hazard();
+	local_irq_restore(flags);
+
+	return 0;
+}
+
+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;
+	pfn_t pfn0, pfn1;
+
+
+	if ((tlb->tlb_hi & VPN2_MASK) == 0) {
+		pfn0 = 0;
+		pfn1 = 0;
+	} else {
+		kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0) >> PAGE_SHIFT);
+		kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1) >> PAGE_SHIFT);
+
+		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);
+
+#ifdef DEBUG
+	kvm_debug("@ %#lx tlb_lo0: 0x%08lx tlb_lo1: 0x%08lx\n", vcpu->arch.pc,
+		  tlb->tlb_lo0, tlb->tlb_lo1);
+#endif
+
+	return kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
+				       tlb->tlb_mask);
+}
+
+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_VPN2(tlb[i]) & ~tlb[i].tlb_mask) == ((entryhi & VPN2_MASK) & ~tlb[i].tlb_mask)) &&
+			(TLB_IS_GLOBAL(tlb[i]) || (TLB_ASID(tlb[i]) == (entryhi & ASID_MASK)))) {
+			index = i;
+			break;
+		}
+	}
+
+#ifdef DEBUG
+	kvm_debug("%s: entryhi: %#lx, index: %d lo0: %#lx, lo1: %#lx\n",
+		  __func__, entryhi, index, tlb[i].tlb_lo0, tlb[i].tlb_lo1);
+#endif
+
+	return index;
+}
+
+int kvm_mips_host_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long vaddr)
+{
+	unsigned long old_entryhi, flags;
+	volatile 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);
+
+#ifdef DEBUG
+	kvm_debug("Host TLB lookup, %#lx, idx: %2d\n", vaddr, idx);
+#endif
+
+	return idx;
+}
+
+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);
+
+#ifdef DEBUG
+	if (idx > 0) {
+		kvm_debug("%s: Invalidated entryhi %#lx @ idx %d\n", __func__,
+			  (va & VPN2_MASK) | (vcpu->arch.asid_map[va & ASID_MASK] & ASID_MASK), idx);
+	}
+#endif
+
+	return 0;
+}
+
+/* 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);
+}
+
+void
+kvm_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu,
+			struct kvm_vcpu *vcpu)
+{
+	unsigned long asid = asid_cache(cpu);
+
+	if (!((asid += ASID_INC) & 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_shadow_tlb_put(struct kvm_vcpu *vcpu)
+{
+	unsigned long flags;
+	unsigned long old_entryhi;
+	unsigned long old_pagemask;
+	int entry = 0;
+	int cpu = smp_processor_id();
+
+	local_irq_save(flags);
+
+	old_entryhi = read_c0_entryhi();
+	old_pagemask = read_c0_pagemask();
+
+	for (entry = 0; entry < current_cpu_data.tlbsize; entry++) {
+		write_c0_index(entry);
+		mtc0_tlbw_hazard();
+		tlb_read();
+		tlbw_use_hazard();
+
+		vcpu->arch.shadow_tlb[cpu][entry].tlb_hi = read_c0_entryhi();
+		vcpu->arch.shadow_tlb[cpu][entry].tlb_lo0 = read_c0_entrylo0();
+		vcpu->arch.shadow_tlb[cpu][entry].tlb_lo1 = read_c0_entrylo1();
+		vcpu->arch.shadow_tlb[cpu][entry].tlb_mask = read_c0_pagemask();
+	}
+
+	write_c0_entryhi(old_entryhi);
+	write_c0_pagemask(old_pagemask);
+	mtc0_tlbw_hazard();
+
+	local_irq_restore(flags);
+
+}
+
+void kvm_shadow_tlb_load(struct kvm_vcpu *vcpu)
+{
+	unsigned long flags;
+	unsigned long old_ctx;
+	int entry;
+	int cpu = smp_processor_id();
+
+	local_irq_save(flags);
+
+	old_ctx = read_c0_entryhi();
+
+	for (entry = 0; entry < current_cpu_data.tlbsize; entry++) {
+		write_c0_entryhi(vcpu->arch.shadow_tlb[cpu][entry].tlb_hi);
+		mtc0_tlbw_hazard();
+		write_c0_entrylo0(vcpu->arch.shadow_tlb[cpu][entry].tlb_lo0);
+		write_c0_entrylo1(vcpu->arch.shadow_tlb[cpu][entry].tlb_lo1);
+
+		write_c0_index(entry);
+		mtc0_tlbw_hazard();
+
+		tlb_write_indexed();
+		tlbw_use_hazard();
+	}
+
+	tlbw_use_hazard();
+	write_c0_entryhi(old_ctx);
+	mtc0_tlbw_hazard();
+	local_irq_restore(flags);
+}
+
+
+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);
+}
+
+void kvm_mips_init_shadow_tlb(struct kvm_vcpu *vcpu)
+{
+	int cpu, entry;
+
+	for_each_possible_cpu(cpu) {
+		for (entry = 0; entry < current_cpu_data.tlbsize; entry++) {
+			vcpu->arch.shadow_tlb[cpu][entry].tlb_hi =
+			    UNIQUE_ENTRYHI(entry);
+			vcpu->arch.shadow_tlb[cpu][entry].tlb_lo0 = 0x0;
+			vcpu->arch.shadow_tlb[cpu][entry].tlb_lo1 = 0x0;
+			vcpu->arch.shadow_tlb[cpu][entry].tlb_mask =
+			    read_c0_pagemask();
+#ifdef DEBUG
+			kvm_debug
+			    ("shadow_tlb[%d][%d]: tlb_hi: %#lx, lo0: %#lx, lo1: %#lx\n",
+			     cpu, entry,
+			     vcpu->arch.shadow_tlb[cpu][entry].tlb_hi,
+			     vcpu->arch.shadow_tlb[cpu][entry].tlb_lo0,
+			     vcpu->arch.shadow_tlb[cpu][entry].tlb_lo1);
+#endif
+		}
+	}
+}
+
+/* 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;
+
+#ifdef DEBUG
+	kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu);
+#endif
+
+	/* 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_info("[%d]: cpu_context: %#lx\n", cpu,
+			 cpu_context(cpu, current->mm));
+		kvm_info("[%d]: Allocated new ASID for Guest Kernel: %#x\n",
+			 cpu, vcpu->arch.guest_kernel_asid[cpu]);
+		kvm_info("[%d]: Allocated new ASID for Guest User: %#x\n", cpu,
+			 vcpu->arch.guest_user_asid[cpu]);
+	}
+
+	if (vcpu->arch.last_sched_cpu != cpu) {
+		kvm_info("[%d->%d]KVM VCPU[%d] switch\n",
+			 vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id);
+	}
+
+	/* Only reload shadow host TLB if new ASIDs haven't been allocated */
+#if 0
+	if ((atomic_read(&kvm_mips_instance) > 1) && !newasid) {
+		kvm_mips_flush_host_tlb(0);
+		kvm_shadow_tlb_load(vcpu);
+	}
+#endif
+
+	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();
+		}
+	}
+
+	local_irq_restore(flags);
+
+}
+
+/* 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;
+
+#if 0
+	if ((atomic_read(&kvm_mips_instance) > 1)) {
+		kvm_shadow_tlb_put(vcpu);
+	}
+#endif
+
+	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);
+}
+
+uint32_t kvm_get_inst(uint32_t *opc, struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = vcpu->arch.cop0;
+	unsigned long paddr, flags;
+	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 {
+			index =
+			    kvm_mips_guest_tlb_lookup(vcpu,
+						      ((unsigned long) opc & VPN2_MASK)
+						      |
+						      (kvm_read_c0_guest_entryhi
+						       (cop0) & ASID_MASK));
+			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_local_flush_tlb_all);
+EXPORT_SYMBOL(kvm_shadow_tlb_put);
+EXPORT_SYMBOL(kvm_mips_handle_mapped_seg_tlb_fault);
+EXPORT_SYMBOL(kvm_mips_handle_commpage_tlb_fault);
+EXPORT_SYMBOL(kvm_mips_init_shadow_tlb);
+EXPORT_SYMBOL(kvm_mips_dump_host_tlbs);
+EXPORT_SYMBOL(kvm_mips_handle_kseg0_tlb_fault);
+EXPORT_SYMBOL(kvm_mips_host_tlb_lookup);
+EXPORT_SYMBOL(kvm_mips_flush_host_tlb);
+EXPORT_SYMBOL(kvm_mips_guest_tlb_lookup);
+EXPORT_SYMBOL(kvm_mips_host_tlb_inv);
+EXPORT_SYMBOL(kvm_mips_translate_guest_kseg0_to_hpa);
+EXPORT_SYMBOL(kvm_shadow_tlb_load);
+EXPORT_SYMBOL(kvm_mips_dump_shadow_tlbs);
+EXPORT_SYMBOL(kvm_mips_dump_guest_tlbs);
+EXPORT_SYMBOL(kvm_get_inst);
+EXPORT_SYMBOL(kvm_arch_vcpu_load);
+EXPORT_SYMBOL(kvm_arch_vcpu_put);