Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 1656 insertions, 0 deletions

diff --git a/kernel/arch/mips/kvm/mips.c b/kernel/arch/mips/kvm/mips.c
new file mode 100644
index 000000000..52f205ae1
--- /dev/null
+++ b/kernel/arch/mips/kvm/mips.c
@@ -0,0 +1,1656 @@
+/*
+ * 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: MIPS specific KVM APIs
+ *
+ * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
+ * Authors: Sanjay Lal <sanjayl@kymasys.com>
+ */
+
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/kdebug.h>
+#include <linux/module.h>
+#include <linux/vmalloc.h>
+#include <linux/fs.h>
+#include <linux/bootmem.h>
+#include <asm/fpu.h>
+#include <asm/page.h>
+#include <asm/cacheflush.h>
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+
+#include <linux/kvm_host.h>
+
+#include "interrupt.h"
+#include "commpage.h"
+
+#define CREATE_TRACE_POINTS
+#include "trace.h"
+
+#ifndef VECTORSPACING
+#define VECTORSPACING 0x100	/* for EI/VI mode */
+#endif
+
+#define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x)
+struct kvm_stats_debugfs_item debugfs_entries[] = {
+	{ "wait",	  VCPU_STAT(wait_exits),	 KVM_STAT_VCPU },
+	{ "cache",	  VCPU_STAT(cache_exits),	 KVM_STAT_VCPU },
+	{ "signal",	  VCPU_STAT(signal_exits),	 KVM_STAT_VCPU },
+	{ "interrupt",	  VCPU_STAT(int_exits),		 KVM_STAT_VCPU },
+	{ "cop_unsuable", VCPU_STAT(cop_unusable_exits), KVM_STAT_VCPU },
+	{ "tlbmod",	  VCPU_STAT(tlbmod_exits),	 KVM_STAT_VCPU },
+	{ "tlbmiss_ld",	  VCPU_STAT(tlbmiss_ld_exits),	 KVM_STAT_VCPU },
+	{ "tlbmiss_st",	  VCPU_STAT(tlbmiss_st_exits),	 KVM_STAT_VCPU },
+	{ "addrerr_st",	  VCPU_STAT(addrerr_st_exits),	 KVM_STAT_VCPU },
+	{ "addrerr_ld",	  VCPU_STAT(addrerr_ld_exits),	 KVM_STAT_VCPU },
+	{ "syscall",	  VCPU_STAT(syscall_exits),	 KVM_STAT_VCPU },
+	{ "resvd_inst",	  VCPU_STAT(resvd_inst_exits),	 KVM_STAT_VCPU },
+	{ "break_inst",	  VCPU_STAT(break_inst_exits),	 KVM_STAT_VCPU },
+	{ "trap_inst",	  VCPU_STAT(trap_inst_exits),	 KVM_STAT_VCPU },
+	{ "msa_fpe",	  VCPU_STAT(msa_fpe_exits),	 KVM_STAT_VCPU },
+	{ "fpe",	  VCPU_STAT(fpe_exits),		 KVM_STAT_VCPU },
+	{ "msa_disabled", VCPU_STAT(msa_disabled_exits), KVM_STAT_VCPU },
+	{ "flush_dcache", VCPU_STAT(flush_dcache_exits), KVM_STAT_VCPU },
+	{ "halt_successful_poll", VCPU_STAT(halt_successful_poll), KVM_STAT_VCPU },
+	{ "halt_wakeup",  VCPU_STAT(halt_wakeup),	 KVM_STAT_VCPU },
+	{NULL}
+};
+
+static int kvm_mips_reset_vcpu(struct kvm_vcpu *vcpu)
+{
+	int i;
+
+	for_each_possible_cpu(i) {
+		vcpu->arch.guest_kernel_asid[i] = 0;
+		vcpu->arch.guest_user_asid[i] = 0;
+	}
+
+	return 0;
+}
+
+/*
+ * XXXKYMA: We are simulatoring a processor that has the WII bit set in
+ * Config7, so we are "runnable" if interrupts are pending
+ */
+int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
+{
+	return !!(vcpu->arch.pending_exceptions);
+}
+
+int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
+{
+	return 1;
+}
+
+int kvm_arch_hardware_enable(void)
+{
+	return 0;
+}
+
+int kvm_arch_hardware_setup(void)
+{
+	return 0;
+}
+
+void kvm_arch_check_processor_compat(void *rtn)
+{
+	*(int *)rtn = 0;
+}
+
+static void kvm_mips_init_tlbs(struct kvm *kvm)
+{
+	unsigned long wired;
+
+	/*
+	 * Add a wired entry to the TLB, it is used to map the commpage to
+	 * the Guest kernel
+	 */
+	wired = read_c0_wired();
+	write_c0_wired(wired + 1);
+	mtc0_tlbw_hazard();
+	kvm->arch.commpage_tlb = wired;
+
+	kvm_debug("[%d] commpage TLB: %d\n", smp_processor_id(),
+		  kvm->arch.commpage_tlb);
+}
+
+static void kvm_mips_init_vm_percpu(void *arg)
+{
+	struct kvm *kvm = (struct kvm *)arg;
+
+	kvm_mips_init_tlbs(kvm);
+	kvm_mips_callbacks->vm_init(kvm);
+
+}
+
+int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
+{
+	if (atomic_inc_return(&kvm_mips_instance) == 1) {
+		kvm_debug("%s: 1st KVM instance, setup host TLB parameters\n",
+			  __func__);
+		on_each_cpu(kvm_mips_init_vm_percpu, kvm, 1);
+	}
+
+	return 0;
+}
+
+void kvm_mips_free_vcpus(struct kvm *kvm)
+{
+	unsigned int i;
+	struct kvm_vcpu *vcpu;
+
+	/* Put the pages we reserved for the guest pmap */
+	for (i = 0; i < kvm->arch.guest_pmap_npages; i++) {
+		if (kvm->arch.guest_pmap[i] != KVM_INVALID_PAGE)
+			kvm_mips_release_pfn_clean(kvm->arch.guest_pmap[i]);
+	}
+	kfree(kvm->arch.guest_pmap);
+
+	kvm_for_each_vcpu(i, vcpu, kvm) {
+		kvm_arch_vcpu_free(vcpu);
+	}
+
+	mutex_lock(&kvm->lock);
+
+	for (i = 0; i < atomic_read(&kvm->online_vcpus); i++)
+		kvm->vcpus[i] = NULL;
+
+	atomic_set(&kvm->online_vcpus, 0);
+
+	mutex_unlock(&kvm->lock);
+}
+
+static void kvm_mips_uninit_tlbs(void *arg)
+{
+	/* Restore wired count */
+	write_c0_wired(0);
+	mtc0_tlbw_hazard();
+	/* Clear out all the TLBs */
+	kvm_local_flush_tlb_all();
+}
+
+void kvm_arch_destroy_vm(struct kvm *kvm)
+{
+	kvm_mips_free_vcpus(kvm);
+
+	/* If this is the last instance, restore wired count */
+	if (atomic_dec_return(&kvm_mips_instance) == 0) {
+		kvm_debug("%s: last KVM instance, restoring TLB parameters\n",
+			  __func__);
+		on_each_cpu(kvm_mips_uninit_tlbs, NULL, 1);
+	}
+}
+
+long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl,
+			unsigned long arg)
+{
+	return -ENOIOCTLCMD;
+}
+
+int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
+			    unsigned long npages)
+{
+	return 0;
+}
+
+int kvm_arch_prepare_memory_region(struct kvm *kvm,
+				   struct kvm_memory_slot *memslot,
+				   struct kvm_userspace_memory_region *mem,
+				   enum kvm_mr_change change)
+{
+	return 0;
+}
+
+void kvm_arch_commit_memory_region(struct kvm *kvm,
+				   struct kvm_userspace_memory_region *mem,
+				   const struct kvm_memory_slot *old,
+				   enum kvm_mr_change change)
+{
+	unsigned long npages = 0;
+	int i;
+
+	kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n",
+		  __func__, kvm, mem->slot, mem->guest_phys_addr,
+		  mem->memory_size, mem->userspace_addr);
+
+	/* Setup Guest PMAP table */
+	if (!kvm->arch.guest_pmap) {
+		if (mem->slot == 0)
+			npages = mem->memory_size >> PAGE_SHIFT;
+
+		if (npages) {
+			kvm->arch.guest_pmap_npages = npages;
+			kvm->arch.guest_pmap =
+			    kzalloc(npages * sizeof(unsigned long), GFP_KERNEL);
+
+			if (!kvm->arch.guest_pmap) {
+				kvm_err("Failed to allocate guest PMAP");
+				return;
+			}
+
+			kvm_debug("Allocated space for Guest PMAP Table (%ld pages) @ %p\n",
+				  npages, kvm->arch.guest_pmap);
+
+			/* Now setup the page table */
+			for (i = 0; i < npages; i++)
+				kvm->arch.guest_pmap[i] = KVM_INVALID_PAGE;
+		}
+	}
+}
+
+struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
+{
+	int err, size, offset;
+	void *gebase;
+	int i;
+
+	struct kvm_vcpu *vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL);
+
+	if (!vcpu) {
+		err = -ENOMEM;
+		goto out;
+	}
+
+	err = kvm_vcpu_init(vcpu, kvm, id);
+
+	if (err)
+		goto out_free_cpu;
+
+	kvm_debug("kvm @ %p: create cpu %d at %p\n", kvm, id, vcpu);
+
+	/*
+	 * Allocate space for host mode exception handlers that handle
+	 * guest mode exits
+	 */
+	if (cpu_has_veic || cpu_has_vint)
+		size = 0x200 + VECTORSPACING * 64;
+	else
+		size = 0x4000;
+
+	/* Save Linux EBASE */
+	vcpu->arch.host_ebase = (void *)read_c0_ebase();
+
+	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
+
+	if (!gebase) {
+		err = -ENOMEM;
+		goto out_free_cpu;
+	}
+	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
+		  ALIGN(size, PAGE_SIZE), gebase);
+
+	/* Save new ebase */
+	vcpu->arch.guest_ebase = gebase;
+
+	/* Copy L1 Guest Exception handler to correct offset */
+
+	/* TLB Refill, EXL = 0 */
+	memcpy(gebase, mips32_exception,
+	       mips32_exceptionEnd - mips32_exception);
+
+	/* General Exception Entry point */
+	memcpy(gebase + 0x180, mips32_exception,
+	       mips32_exceptionEnd - mips32_exception);
+
+	/* For vectored interrupts poke the exception code @ all offsets 0-7 */
+	for (i = 0; i < 8; i++) {
+		kvm_debug("L1 Vectored handler @ %p\n",
+			  gebase + 0x200 + (i * VECTORSPACING));
+		memcpy(gebase + 0x200 + (i * VECTORSPACING), mips32_exception,
+		       mips32_exceptionEnd - mips32_exception);
+	}
+
+	/* General handler, relocate to unmapped space for sanity's sake */
+	offset = 0x2000;
+	kvm_debug("Installing KVM Exception handlers @ %p, %#x bytes\n",
+		  gebase + offset,
+		  mips32_GuestExceptionEnd - mips32_GuestException);
+
+	memcpy(gebase + offset, mips32_GuestException,
+	       mips32_GuestExceptionEnd - mips32_GuestException);
+
+	/* Invalidate the icache for these ranges */
+	local_flush_icache_range((unsigned long)gebase,
+				(unsigned long)gebase + ALIGN(size, PAGE_SIZE));
+
+	/*
+	 * Allocate comm page for guest kernel, a TLB will be reserved for
+	 * mapping GVA @ 0xFFFF8000 to this page
+	 */
+	vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL);
+
+	if (!vcpu->arch.kseg0_commpage) {
+		err = -ENOMEM;
+		goto out_free_gebase;
+	}
+
+	kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage);
+	kvm_mips_commpage_init(vcpu);
+
+	/* Init */
+	vcpu->arch.last_sched_cpu = -1;
+
+	/* Start off the timer */
+	kvm_mips_init_count(vcpu);
+
+	return vcpu;
+
+out_free_gebase:
+	kfree(gebase);
+
+out_free_cpu:
+	kfree(vcpu);
+
+out:
+	return ERR_PTR(err);
+}
+
+void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu)
+{
+	hrtimer_cancel(&vcpu->arch.comparecount_timer);
+
+	kvm_vcpu_uninit(vcpu);
+
+	kvm_mips_dump_stats(vcpu);
+
+	kfree(vcpu->arch.guest_ebase);
+	kfree(vcpu->arch.kseg0_commpage);
+	kfree(vcpu);
+}
+
+void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu)
+{
+	kvm_arch_vcpu_free(vcpu);
+}
+
+int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu,
+					struct kvm_guest_debug *dbg)
+{
+	return -ENOIOCTLCMD;
+}
+
+int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
+{
+	int r = 0;
+	sigset_t sigsaved;
+
+	if (vcpu->sigset_active)
+		sigprocmask(SIG_SETMASK, &vcpu->sigset, &sigsaved);
+
+	if (vcpu->mmio_needed) {
+		if (!vcpu->mmio_is_write)
+			kvm_mips_complete_mmio_load(vcpu, run);
+		vcpu->mmio_needed = 0;
+	}
+
+	lose_fpu(1);
+
+	local_irq_disable();
+	/* Check if we have any exceptions/interrupts pending */
+	kvm_mips_deliver_interrupts(vcpu,
+				    kvm_read_c0_guest_cause(vcpu->arch.cop0));
+
+	kvm_guest_enter();
+
+	/* Disable hardware page table walking while in guest */
+	htw_stop();
+
+	r = __kvm_mips_vcpu_run(run, vcpu);
+
+	/* Re-enable HTW before enabling interrupts */
+	htw_start();
+
+	kvm_guest_exit();
+	local_irq_enable();
+
+	if (vcpu->sigset_active)
+		sigprocmask(SIG_SETMASK, &sigsaved, NULL);
+
+	return r;
+}
+
+int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
+			     struct kvm_mips_interrupt *irq)
+{
+	int intr = (int)irq->irq;
+	struct kvm_vcpu *dvcpu = NULL;
+
+	if (intr == 3 || intr == -3 || intr == 4 || intr == -4)
+		kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu,
+			  (int)intr);
+
+	if (irq->cpu == -1)
+		dvcpu = vcpu;
+	else
+		dvcpu = vcpu->kvm->vcpus[irq->cpu];
+
+	if (intr == 2 || intr == 3 || intr == 4) {
+		kvm_mips_callbacks->queue_io_int(dvcpu, irq);
+
+	} else if (intr == -2 || intr == -3 || intr == -4) {
+		kvm_mips_callbacks->dequeue_io_int(dvcpu, irq);
+	} else {
+		kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__,
+			irq->cpu, irq->irq);
+		return -EINVAL;
+	}
+
+	dvcpu->arch.wait = 0;
+
+	if (waitqueue_active(&dvcpu->wq))
+		wake_up_interruptible(&dvcpu->wq);
+
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu,
+				    struct kvm_mp_state *mp_state)
+{
+	return -ENOIOCTLCMD;
+}
+
+int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,
+				    struct kvm_mp_state *mp_state)
+{
+	return -ENOIOCTLCMD;
+}
+
+static u64 kvm_mips_get_one_regs[] = {
+	KVM_REG_MIPS_R0,
+	KVM_REG_MIPS_R1,
+	KVM_REG_MIPS_R2,
+	KVM_REG_MIPS_R3,
+	KVM_REG_MIPS_R4,
+	KVM_REG_MIPS_R5,
+	KVM_REG_MIPS_R6,
+	KVM_REG_MIPS_R7,
+	KVM_REG_MIPS_R8,
+	KVM_REG_MIPS_R9,
+	KVM_REG_MIPS_R10,
+	KVM_REG_MIPS_R11,
+	KVM_REG_MIPS_R12,
+	KVM_REG_MIPS_R13,
+	KVM_REG_MIPS_R14,
+	KVM_REG_MIPS_R15,
+	KVM_REG_MIPS_R16,
+	KVM_REG_MIPS_R17,
+	KVM_REG_MIPS_R18,
+	KVM_REG_MIPS_R19,
+	KVM_REG_MIPS_R20,
+	KVM_REG_MIPS_R21,
+	KVM_REG_MIPS_R22,
+	KVM_REG_MIPS_R23,
+	KVM_REG_MIPS_R24,
+	KVM_REG_MIPS_R25,
+	KVM_REG_MIPS_R26,
+	KVM_REG_MIPS_R27,
+	KVM_REG_MIPS_R28,
+	KVM_REG_MIPS_R29,
+	KVM_REG_MIPS_R30,
+	KVM_REG_MIPS_R31,
+
+	KVM_REG_MIPS_HI,
+	KVM_REG_MIPS_LO,
+	KVM_REG_MIPS_PC,
+
+	KVM_REG_MIPS_CP0_INDEX,
+	KVM_REG_MIPS_CP0_CONTEXT,
+	KVM_REG_MIPS_CP0_USERLOCAL,
+	KVM_REG_MIPS_CP0_PAGEMASK,
+	KVM_REG_MIPS_CP0_WIRED,
+	KVM_REG_MIPS_CP0_HWRENA,
+	KVM_REG_MIPS_CP0_BADVADDR,
+	KVM_REG_MIPS_CP0_COUNT,
+	KVM_REG_MIPS_CP0_ENTRYHI,
+	KVM_REG_MIPS_CP0_COMPARE,
+	KVM_REG_MIPS_CP0_STATUS,
+	KVM_REG_MIPS_CP0_CAUSE,
+	KVM_REG_MIPS_CP0_EPC,
+	KVM_REG_MIPS_CP0_PRID,
+	KVM_REG_MIPS_CP0_CONFIG,
+	KVM_REG_MIPS_CP0_CONFIG1,
+	KVM_REG_MIPS_CP0_CONFIG2,
+	KVM_REG_MIPS_CP0_CONFIG3,
+	KVM_REG_MIPS_CP0_CONFIG4,
+	KVM_REG_MIPS_CP0_CONFIG5,
+	KVM_REG_MIPS_CP0_CONFIG7,
+	KVM_REG_MIPS_CP0_ERROREPC,
+
+	KVM_REG_MIPS_COUNT_CTL,
+	KVM_REG_MIPS_COUNT_RESUME,
+	KVM_REG_MIPS_COUNT_HZ,
+};
+
+static int kvm_mips_get_reg(struct kvm_vcpu *vcpu,
+			    const struct kvm_one_reg *reg)
+{
+	struct mips_coproc *cop0 = vcpu->arch.cop0;
+	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
+	int ret;
+	s64 v;
+	s64 vs[2];
+	unsigned int idx;
+
+	switch (reg->id) {
+	/* General purpose registers */
+	case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31:
+		v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0];
+		break;
+	case KVM_REG_MIPS_HI:
+		v = (long)vcpu->arch.hi;
+		break;
+	case KVM_REG_MIPS_LO:
+		v = (long)vcpu->arch.lo;
+		break;
+	case KVM_REG_MIPS_PC:
+		v = (long)vcpu->arch.pc;
+		break;
+
+	/* Floating point registers */
+	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
+		/* Odd singles in top of even double when FR=0 */
+		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
+			v = get_fpr32(&fpu->fpr[idx], 0);
+		else
+			v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1);
+		break;
+	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
+		/* Can't access odd doubles in FR=0 mode */
+		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
+			return -EINVAL;
+		v = get_fpr64(&fpu->fpr[idx], 0);
+		break;
+	case KVM_REG_MIPS_FCR_IR:
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		v = boot_cpu_data.fpu_id;
+		break;
+	case KVM_REG_MIPS_FCR_CSR:
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		v = fpu->fcr31;
+		break;
+
+	/* MIPS SIMD Architecture (MSA) registers */
+	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		/* Can't access MSA registers in FR=0 mode */
+		if (!(kvm_read_c0_guest_status(cop0) & ST0_FR))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+		/* least significant byte first */
+		vs[0] = get_fpr64(&fpu->fpr[idx], 0);
+		vs[1] = get_fpr64(&fpu->fpr[idx], 1);
+#else
+		/* most significant byte first */
+		vs[0] = get_fpr64(&fpu->fpr[idx], 1);
+		vs[1] = get_fpr64(&fpu->fpr[idx], 0);
+#endif
+		break;
+	case KVM_REG_MIPS_MSA_IR:
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		v = boot_cpu_data.msa_id;
+		break;
+	case KVM_REG_MIPS_MSA_CSR:
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		v = fpu->msacsr;
+		break;
+
+	/* Co-processor 0 registers */
+	case KVM_REG_MIPS_CP0_INDEX:
+		v = (long)kvm_read_c0_guest_index(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_CONTEXT:
+		v = (long)kvm_read_c0_guest_context(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_USERLOCAL:
+		v = (long)kvm_read_c0_guest_userlocal(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_PAGEMASK:
+		v = (long)kvm_read_c0_guest_pagemask(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_WIRED:
+		v = (long)kvm_read_c0_guest_wired(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_HWRENA:
+		v = (long)kvm_read_c0_guest_hwrena(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_BADVADDR:
+		v = (long)kvm_read_c0_guest_badvaddr(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_ENTRYHI:
+		v = (long)kvm_read_c0_guest_entryhi(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_COMPARE:
+		v = (long)kvm_read_c0_guest_compare(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_STATUS:
+		v = (long)kvm_read_c0_guest_status(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_CAUSE:
+		v = (long)kvm_read_c0_guest_cause(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_EPC:
+		v = (long)kvm_read_c0_guest_epc(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_PRID:
+		v = (long)kvm_read_c0_guest_prid(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG:
+		v = (long)kvm_read_c0_guest_config(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG1:
+		v = (long)kvm_read_c0_guest_config1(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG2:
+		v = (long)kvm_read_c0_guest_config2(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG3:
+		v = (long)kvm_read_c0_guest_config3(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG4:
+		v = (long)kvm_read_c0_guest_config4(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG5:
+		v = (long)kvm_read_c0_guest_config5(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_CONFIG7:
+		v = (long)kvm_read_c0_guest_config7(cop0);
+		break;
+	case KVM_REG_MIPS_CP0_ERROREPC:
+		v = (long)kvm_read_c0_guest_errorepc(cop0);
+		break;
+	/* registers to be handled specially */
+	case KVM_REG_MIPS_CP0_COUNT:
+	case KVM_REG_MIPS_COUNT_CTL:
+	case KVM_REG_MIPS_COUNT_RESUME:
+	case KVM_REG_MIPS_COUNT_HZ:
+		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
+		if (ret)
+			return ret;
+		break;
+	default:
+		return -EINVAL;
+	}
+	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
+		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
+
+		return put_user(v, uaddr64);
+	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
+		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
+		u32 v32 = (u32)v;
+
+		return put_user(v32, uaddr32);
+	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
+		void __user *uaddr = (void __user *)(long)reg->addr;
+
+		return copy_to_user(uaddr, vs, 16);
+	} else {
+		return -EINVAL;
+	}
+}
+
+static int kvm_mips_set_reg(struct kvm_vcpu *vcpu,
+			    const struct kvm_one_reg *reg)
+{
+	struct mips_coproc *cop0 = vcpu->arch.cop0;
+	struct mips_fpu_struct *fpu = &vcpu->arch.fpu;
+	s64 v;
+	s64 vs[2];
+	unsigned int idx;
+
+	if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) {
+		u64 __user *uaddr64 = (u64 __user *)(long)reg->addr;
+
+		if (get_user(v, uaddr64) != 0)
+			return -EFAULT;
+	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) {
+		u32 __user *uaddr32 = (u32 __user *)(long)reg->addr;
+		s32 v32;
+
+		if (get_user(v32, uaddr32) != 0)
+			return -EFAULT;
+		v = (s64)v32;
+	} else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) {
+		void __user *uaddr = (void __user *)(long)reg->addr;
+
+		return copy_from_user(vs, uaddr, 16);
+	} else {
+		return -EINVAL;
+	}
+
+	switch (reg->id) {
+	/* General purpose registers */
+	case KVM_REG_MIPS_R0:
+		/* Silently ignore requests to set $0 */
+		break;
+	case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31:
+		vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v;
+		break;
+	case KVM_REG_MIPS_HI:
+		vcpu->arch.hi = v;
+		break;
+	case KVM_REG_MIPS_LO:
+		vcpu->arch.lo = v;
+		break;
+	case KVM_REG_MIPS_PC:
+		vcpu->arch.pc = v;
+		break;
+
+	/* Floating point registers */
+	case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31):
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_FPR_32(0);
+		/* Odd singles in top of even double when FR=0 */
+		if (kvm_read_c0_guest_status(cop0) & ST0_FR)
+			set_fpr32(&fpu->fpr[idx], 0, v);
+		else
+			set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v);
+		break;
+	case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31):
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_FPR_64(0);
+		/* Can't access odd doubles in FR=0 mode */
+		if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR))
+			return -EINVAL;
+		set_fpr64(&fpu->fpr[idx], 0, v);
+		break;
+	case KVM_REG_MIPS_FCR_IR:
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		/* Read-only */
+		break;
+	case KVM_REG_MIPS_FCR_CSR:
+		if (!kvm_mips_guest_has_fpu(&vcpu->arch))
+			return -EINVAL;
+		fpu->fcr31 = v;
+		break;
+
+	/* MIPS SIMD Architecture (MSA) registers */
+	case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31):
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		idx = reg->id - KVM_REG_MIPS_VEC_128(0);
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+		/* least significant byte first */
+		set_fpr64(&fpu->fpr[idx], 0, vs[0]);
+		set_fpr64(&fpu->fpr[idx], 1, vs[1]);
+#else
+		/* most significant byte first */
+		set_fpr64(&fpu->fpr[idx], 1, vs[0]);
+		set_fpr64(&fpu->fpr[idx], 0, vs[1]);
+#endif
+		break;
+	case KVM_REG_MIPS_MSA_IR:
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		/* Read-only */
+		break;
+	case KVM_REG_MIPS_MSA_CSR:
+		if (!kvm_mips_guest_has_msa(&vcpu->arch))
+			return -EINVAL;
+		fpu->msacsr = v;
+		break;
+
+	/* Co-processor 0 registers */
+	case KVM_REG_MIPS_CP0_INDEX:
+		kvm_write_c0_guest_index(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_CONTEXT:
+		kvm_write_c0_guest_context(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_USERLOCAL:
+		kvm_write_c0_guest_userlocal(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_PAGEMASK:
+		kvm_write_c0_guest_pagemask(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_WIRED:
+		kvm_write_c0_guest_wired(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_HWRENA:
+		kvm_write_c0_guest_hwrena(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_BADVADDR:
+		kvm_write_c0_guest_badvaddr(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_ENTRYHI:
+		kvm_write_c0_guest_entryhi(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_STATUS:
+		kvm_write_c0_guest_status(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_EPC:
+		kvm_write_c0_guest_epc(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_PRID:
+		kvm_write_c0_guest_prid(cop0, v);
+		break;
+	case KVM_REG_MIPS_CP0_ERROREPC:
+		kvm_write_c0_guest_errorepc(cop0, v);
+		break;
+	/* registers to be handled specially */
+	case KVM_REG_MIPS_CP0_COUNT:
+	case KVM_REG_MIPS_CP0_COMPARE:
+	case KVM_REG_MIPS_CP0_CAUSE:
+	case KVM_REG_MIPS_CP0_CONFIG:
+	case KVM_REG_MIPS_CP0_CONFIG1:
+	case KVM_REG_MIPS_CP0_CONFIG2:
+	case KVM_REG_MIPS_CP0_CONFIG3:
+	case KVM_REG_MIPS_CP0_CONFIG4:
+	case KVM_REG_MIPS_CP0_CONFIG5:
+	case KVM_REG_MIPS_COUNT_CTL:
+	case KVM_REG_MIPS_COUNT_RESUME:
+	case KVM_REG_MIPS_COUNT_HZ:
+		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
+	default:
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu,
+				     struct kvm_enable_cap *cap)
+{
+	int r = 0;
+
+	if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap))
+		return -EINVAL;
+	if (cap->flags)
+		return -EINVAL;
+	if (cap->args[0])
+		return -EINVAL;
+
+	switch (cap->cap) {
+	case KVM_CAP_MIPS_FPU:
+		vcpu->arch.fpu_enabled = true;
+		break;
+	case KVM_CAP_MIPS_MSA:
+		vcpu->arch.msa_enabled = true;
+		break;
+	default:
+		r = -EINVAL;
+		break;
+	}
+
+	return r;
+}
+
+long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
+			 unsigned long arg)
+{
+	struct kvm_vcpu *vcpu = filp->private_data;
+	void __user *argp = (void __user *)arg;
+	long r;
+
+	switch (ioctl) {
+	case KVM_SET_ONE_REG:
+	case KVM_GET_ONE_REG: {
+		struct kvm_one_reg reg;
+
+		if (copy_from_user(&reg, argp, sizeof(reg)))
+			return -EFAULT;
+		if (ioctl == KVM_SET_ONE_REG)
+			return kvm_mips_set_reg(vcpu, &reg);
+		else
+			return kvm_mips_get_reg(vcpu, &reg);
+	}
+	case KVM_GET_REG_LIST: {
+		struct kvm_reg_list __user *user_list = argp;
+		u64 __user *reg_dest;
+		struct kvm_reg_list reg_list;
+		unsigned n;
+
+		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
+			return -EFAULT;
+		n = reg_list.n;
+		reg_list.n = ARRAY_SIZE(kvm_mips_get_one_regs);
+		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
+			return -EFAULT;
+		if (n < reg_list.n)
+			return -E2BIG;
+		reg_dest = user_list->reg;
+		if (copy_to_user(reg_dest, kvm_mips_get_one_regs,
+				 sizeof(kvm_mips_get_one_regs)))
+			return -EFAULT;
+		return 0;
+	}
+	case KVM_NMI:
+		/* Treat the NMI as a CPU reset */
+		r = kvm_mips_reset_vcpu(vcpu);
+		break;
+	case KVM_INTERRUPT:
+		{
+			struct kvm_mips_interrupt irq;
+
+			r = -EFAULT;
+			if (copy_from_user(&irq, argp, sizeof(irq)))
+				goto out;
+
+			kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
+				  irq.irq);
+
+			r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
+			break;
+		}
+	case KVM_ENABLE_CAP: {
+		struct kvm_enable_cap cap;
+
+		r = -EFAULT;
+		if (copy_from_user(&cap, argp, sizeof(cap)))
+			goto out;
+		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
+		break;
+	}
+	default:
+		r = -ENOIOCTLCMD;
+	}
+
+out:
+	return r;
+}
+
+/* Get (and clear) the dirty memory log for a memory slot. */
+int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
+{
+	struct kvm_memory_slot *memslot;
+	unsigned long ga, ga_end;
+	int is_dirty = 0;
+	int r;
+	unsigned long n;
+
+	mutex_lock(&kvm->slots_lock);
+
+	r = kvm_get_dirty_log(kvm, log, &is_dirty);
+	if (r)
+		goto out;
+
+	/* If nothing is dirty, don't bother messing with page tables. */
+	if (is_dirty) {
+		memslot = id_to_memslot(kvm->memslots, log->slot);
+
+		ga = memslot->base_gfn << PAGE_SHIFT;
+		ga_end = ga + (memslot->npages << PAGE_SHIFT);
+
+		kvm_info("%s: dirty, ga: %#lx, ga_end %#lx\n", __func__, ga,
+			 ga_end);
+
+		n = kvm_dirty_bitmap_bytes(memslot);
+		memset(memslot->dirty_bitmap, 0, n);
+	}
+
+	r = 0;
+out:
+	mutex_unlock(&kvm->slots_lock);
+	return r;
+
+}
+
+long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg)
+{
+	long r;
+
+	switch (ioctl) {
+	default:
+		r = -ENOIOCTLCMD;
+	}
+
+	return r;
+}
+
+int kvm_arch_init(void *opaque)
+{
+	if (kvm_mips_callbacks) {
+		kvm_err("kvm: module already exists\n");
+		return -EEXIST;
+	}
+
+	return kvm_mips_emulation_init(&kvm_mips_callbacks);
+}
+
+void kvm_arch_exit(void)
+{
+	kvm_mips_callbacks = NULL;
+}
+
+int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
+				  struct kvm_sregs *sregs)
+{
+	return -ENOIOCTLCMD;
+}
+
+int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
+				  struct kvm_sregs *sregs)
+{
+	return -ENOIOCTLCMD;
+}
+
+void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)
+{
+}
+
+int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
+{
+	return -ENOIOCTLCMD;
+}
+
+int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
+{
+	return -ENOIOCTLCMD;
+}
+
+int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)
+{
+	return VM_FAULT_SIGBUS;
+}
+
+int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
+{
+	int r;
+
+	switch (ext) {
+	case KVM_CAP_ONE_REG:
+	case KVM_CAP_ENABLE_CAP:
+		r = 1;
+		break;
+	case KVM_CAP_COALESCED_MMIO:
+		r = KVM_COALESCED_MMIO_PAGE_OFFSET;
+		break;
+	case KVM_CAP_MIPS_FPU:
+		r = !!cpu_has_fpu;
+		break;
+	case KVM_CAP_MIPS_MSA:
+		/*
+		 * We don't support MSA vector partitioning yet:
+		 * 1) It would require explicit support which can't be tested
+		 *    yet due to lack of support in current hardware.
+		 * 2) It extends the state that would need to be saved/restored
+		 *    by e.g. QEMU for migration.
+		 *
+		 * When vector partitioning hardware becomes available, support
+		 * could be added by requiring a flag when enabling
+		 * KVM_CAP_MIPS_MSA capability to indicate that userland knows
+		 * to save/restore the appropriate extra state.
+		 */
+		r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF);
+		break;
+	default:
+		r = 0;
+		break;
+	}
+	return r;
+}
+
+int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
+{
+	return kvm_mips_pending_timer(vcpu);
+}
+
+int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu)
+{
+	int i;
+	struct mips_coproc *cop0;
+
+	if (!vcpu)
+		return -1;
+
+	kvm_debug("VCPU Register Dump:\n");
+	kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc);
+	kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);
+
+	for (i = 0; i < 32; i += 4) {
+		kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i,
+		       vcpu->arch.gprs[i],
+		       vcpu->arch.gprs[i + 1],
+		       vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]);
+	}
+	kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi);
+	kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo);
+
+	cop0 = vcpu->arch.cop0;
+	kvm_debug("\tStatus: 0x%08lx, Cause: 0x%08lx\n",
+		  kvm_read_c0_guest_status(cop0),
+		  kvm_read_c0_guest_cause(cop0));
+
+	kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0));
+
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+	int i;
+
+	for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
+		vcpu->arch.gprs[i] = regs->gpr[i];
+	vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */
+	vcpu->arch.hi = regs->hi;
+	vcpu->arch.lo = regs->lo;
+	vcpu->arch.pc = regs->pc;
+
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++)
+		regs->gpr[i] = vcpu->arch.gprs[i];
+
+	regs->hi = vcpu->arch.hi;
+	regs->lo = vcpu->arch.lo;
+	regs->pc = vcpu->arch.pc;
+
+	return 0;
+}
+
+static void kvm_mips_comparecount_func(unsigned long data)
+{
+	struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data;
+
+	kvm_mips_callbacks->queue_timer_int(vcpu);
+
+	vcpu->arch.wait = 0;
+	if (waitqueue_active(&vcpu->wq))
+		wake_up_interruptible(&vcpu->wq);
+}
+
+/* low level hrtimer wake routine */
+static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer)
+{
+	struct kvm_vcpu *vcpu;
+
+	vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer);
+	kvm_mips_comparecount_func((unsigned long) vcpu);
+	return kvm_mips_count_timeout(vcpu);
+}
+
+int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu)
+{
+	kvm_mips_callbacks->vcpu_init(vcpu);
+	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
+		     HRTIMER_MODE_REL);
+	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
+				  struct kvm_translation *tr)
+{
+	return 0;
+}
+
+/* Initial guest state */
+int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu)
+{
+	return kvm_mips_callbacks->vcpu_setup(vcpu);
+}
+
+static void kvm_mips_set_c0_status(void)
+{
+	uint32_t status = read_c0_status();
+
+	if (cpu_has_dsp)
+		status |= (ST0_MX);
+
+	write_c0_status(status);
+	ehb();
+}
+
+/*
+ * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV)
+ */
+int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu)
+{
+	uint32_t cause = vcpu->arch.host_cp0_cause;
+	uint32_t exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
+	uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
+	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
+	enum emulation_result er = EMULATE_DONE;
+	int ret = RESUME_GUEST;
+
+	/* re-enable HTW before enabling interrupts */
+	htw_start();
+
+	/* Set a default exit reason */
+	run->exit_reason = KVM_EXIT_UNKNOWN;
+	run->ready_for_interrupt_injection = 1;
+
+	/*
+	 * Set the appropriate status bits based on host CPU features,
+	 * before we hit the scheduler
+	 */
+	kvm_mips_set_c0_status();
+
+	local_irq_enable();
+
+	kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n",
+			cause, opc, run, vcpu);
+
+	/*
+	 * Do a privilege check, if in UM most of these exit conditions end up
+	 * causing an exception to be delivered to the Guest Kernel
+	 */
+	er = kvm_mips_check_privilege(cause, opc, run, vcpu);
+	if (er == EMULATE_PRIV_FAIL) {
+		goto skip_emul;
+	} else if (er == EMULATE_FAIL) {
+		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		ret = RESUME_HOST;
+		goto skip_emul;
+	}
+
+	switch (exccode) {
+	case T_INT:
+		kvm_debug("[%d]T_INT @ %p\n", vcpu->vcpu_id, opc);
+
+		++vcpu->stat.int_exits;
+		trace_kvm_exit(vcpu, INT_EXITS);
+
+		if (need_resched())
+			cond_resched();
+
+		ret = RESUME_GUEST;
+		break;
+
+	case T_COP_UNUSABLE:
+		kvm_debug("T_COP_UNUSABLE: @ PC: %p\n", opc);
+
+		++vcpu->stat.cop_unusable_exits;
+		trace_kvm_exit(vcpu, COP_UNUSABLE_EXITS);
+		ret = kvm_mips_callbacks->handle_cop_unusable(vcpu);
+		/* XXXKYMA: Might need to return to user space */
+		if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN)
+			ret = RESUME_HOST;
+		break;
+
+	case T_TLB_MOD:
+		++vcpu->stat.tlbmod_exits;
+		trace_kvm_exit(vcpu, TLBMOD_EXITS);
+		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
+		break;
+
+	case T_TLB_ST_MISS:
+		kvm_debug("TLB ST fault:  cause %#x, status %#lx, PC: %p, BadVaddr: %#lx\n",
+			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
+			  badvaddr);
+
+		++vcpu->stat.tlbmiss_st_exits;
+		trace_kvm_exit(vcpu, TLBMISS_ST_EXITS);
+		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
+		break;
+
+	case T_TLB_LD_MISS:
+		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
+			  cause, opc, badvaddr);
+
+		++vcpu->stat.tlbmiss_ld_exits;
+		trace_kvm_exit(vcpu, TLBMISS_LD_EXITS);
+		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
+		break;
+
+	case T_ADDR_ERR_ST:
+		++vcpu->stat.addrerr_st_exits;
+		trace_kvm_exit(vcpu, ADDRERR_ST_EXITS);
+		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
+		break;
+
+	case T_ADDR_ERR_LD:
+		++vcpu->stat.addrerr_ld_exits;
+		trace_kvm_exit(vcpu, ADDRERR_LD_EXITS);
+		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
+		break;
+
+	case T_SYSCALL:
+		++vcpu->stat.syscall_exits;
+		trace_kvm_exit(vcpu, SYSCALL_EXITS);
+		ret = kvm_mips_callbacks->handle_syscall(vcpu);
+		break;
+
+	case T_RES_INST:
+		++vcpu->stat.resvd_inst_exits;
+		trace_kvm_exit(vcpu, RESVD_INST_EXITS);
+		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
+		break;
+
+	case T_BREAK:
+		++vcpu->stat.break_inst_exits;
+		trace_kvm_exit(vcpu, BREAK_INST_EXITS);
+		ret = kvm_mips_callbacks->handle_break(vcpu);
+		break;
+
+	case T_TRAP:
+		++vcpu->stat.trap_inst_exits;
+		trace_kvm_exit(vcpu, TRAP_INST_EXITS);
+		ret = kvm_mips_callbacks->handle_trap(vcpu);
+		break;
+
+	case T_MSAFPE:
+		++vcpu->stat.msa_fpe_exits;
+		trace_kvm_exit(vcpu, MSA_FPE_EXITS);
+		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
+		break;
+
+	case T_FPE:
+		++vcpu->stat.fpe_exits;
+		trace_kvm_exit(vcpu, FPE_EXITS);
+		ret = kvm_mips_callbacks->handle_fpe(vcpu);
+		break;
+
+	case T_MSADIS:
+		++vcpu->stat.msa_disabled_exits;
+		trace_kvm_exit(vcpu, MSA_DISABLED_EXITS);
+		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
+		break;
+
+	default:
+		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#lx\n",
+			exccode, opc, kvm_get_inst(opc, vcpu), badvaddr,
+			kvm_read_c0_guest_status(vcpu->arch.cop0));
+		kvm_arch_vcpu_dump_regs(vcpu);
+		run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
+		ret = RESUME_HOST;
+		break;
+
+	}
+
+skip_emul:
+	local_irq_disable();
+
+	if (er == EMULATE_DONE && !(ret & RESUME_HOST))
+		kvm_mips_deliver_interrupts(vcpu, cause);
+
+	if (!(ret & RESUME_HOST)) {
+		/* Only check for signals if not already exiting to userspace */
+		if (signal_pending(current)) {
+			run->exit_reason = KVM_EXIT_INTR;
+			ret = (-EINTR << 2) | RESUME_HOST;
+			++vcpu->stat.signal_exits;
+			trace_kvm_exit(vcpu, SIGNAL_EXITS);
+		}
+	}
+
+	if (ret == RESUME_GUEST) {
+		/*
+		 * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context
+		 * is live), restore FCR31 / MSACSR.
+		 *
+		 * This should be before returning to the guest exception
+		 * vector, as it may well cause an [MSA] FP exception if there
+		 * are pending exception bits unmasked. (see
+		 * kvm_mips_csr_die_notifier() for how that is handled).
+		 */
+		if (kvm_mips_guest_has_fpu(&vcpu->arch) &&
+		    read_c0_status() & ST0_CU1)
+			__kvm_restore_fcsr(&vcpu->arch);
+
+		if (kvm_mips_guest_has_msa(&vcpu->arch) &&
+		    read_c0_config5() & MIPS_CONF5_MSAEN)
+			__kvm_restore_msacsr(&vcpu->arch);
+	}
+
+	/* Disable HTW before returning to guest or host */
+	htw_stop();
+
+	return ret;
+}
+
+/* Enable FPU for guest and restore context */
+void kvm_own_fpu(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = vcpu->arch.cop0;
+	unsigned int sr, cfg5;
+
+	preempt_disable();
+
+	sr = kvm_read_c0_guest_status(cop0);
+
+	/*
+	 * If MSA state is already live, it is undefined how it interacts with
+	 * FR=0 FPU state, and we don't want to hit reserved instruction
+	 * exceptions trying to save the MSA state later when CU=1 && FR=1, so
+	 * play it safe and save it first.
+	 *
+	 * In theory we shouldn't ever hit this case since kvm_lose_fpu() should
+	 * get called when guest CU1 is set, however we can't trust the guest
+	 * not to clobber the status register directly via the commpage.
+	 */
+	if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) &&
+	    vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA)
+		kvm_lose_fpu(vcpu);
+
+	/*
+	 * Enable FPU for guest
+	 * We set FR and FRE according to guest context
+	 */
+	change_c0_status(ST0_CU1 | ST0_FR, sr);
+	if (cpu_has_fre) {
+		cfg5 = kvm_read_c0_guest_config5(cop0);
+		change_c0_config5(MIPS_CONF5_FRE, cfg5);
+	}
+	enable_fpu_hazard();
+
+	/* If guest FPU state not active, restore it now */
+	if (!(vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU)) {
+		__kvm_restore_fpu(&vcpu->arch);
+		vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_FPU;
+	}
+
+	preempt_enable();
+}
+
+#ifdef CONFIG_CPU_HAS_MSA
+/* Enable MSA for guest and restore context */
+void kvm_own_msa(struct kvm_vcpu *vcpu)
+{
+	struct mips_coproc *cop0 = vcpu->arch.cop0;
+	unsigned int sr, cfg5;
+
+	preempt_disable();
+
+	/*
+	 * Enable FPU if enabled in guest, since we're restoring FPU context
+	 * anyway. We set FR and FRE according to guest context.
+	 */
+	if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
+		sr = kvm_read_c0_guest_status(cop0);
+
+		/*
+		 * If FR=0 FPU state is already live, it is undefined how it
+		 * interacts with MSA state, so play it safe and save it first.
+		 */
+		if (!(sr & ST0_FR) &&
+		    (vcpu->arch.fpu_inuse & (KVM_MIPS_FPU_FPU |
+				KVM_MIPS_FPU_MSA)) == KVM_MIPS_FPU_FPU)
+			kvm_lose_fpu(vcpu);
+
+		change_c0_status(ST0_CU1 | ST0_FR, sr);
+		if (sr & ST0_CU1 && cpu_has_fre) {
+			cfg5 = kvm_read_c0_guest_config5(cop0);
+			change_c0_config5(MIPS_CONF5_FRE, cfg5);
+		}
+	}
+
+	/* Enable MSA for guest */
+	set_c0_config5(MIPS_CONF5_MSAEN);
+	enable_fpu_hazard();
+
+	switch (vcpu->arch.fpu_inuse & (KVM_MIPS_FPU_FPU | KVM_MIPS_FPU_MSA)) {
+	case KVM_MIPS_FPU_FPU:
+		/*
+		 * Guest FPU state already loaded, only restore upper MSA state
+		 */
+		__kvm_restore_msa_upper(&vcpu->arch);
+		vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_MSA;
+		break;
+	case 0:
+		/* Neither FPU or MSA already active, restore full MSA state */
+		__kvm_restore_msa(&vcpu->arch);
+		vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_MSA;
+		if (kvm_mips_guest_has_fpu(&vcpu->arch))
+			vcpu->arch.fpu_inuse |= KVM_MIPS_FPU_FPU;
+		break;
+	default:
+		break;
+	}
+
+	preempt_enable();
+}
+#endif
+
+/* Drop FPU & MSA without saving it */
+void kvm_drop_fpu(struct kvm_vcpu *vcpu)
+{
+	preempt_disable();
+	if (cpu_has_msa && vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA) {
+		disable_msa();
+		vcpu->arch.fpu_inuse &= ~KVM_MIPS_FPU_MSA;
+	}
+	if (vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU) {
+		clear_c0_status(ST0_CU1 | ST0_FR);
+		vcpu->arch.fpu_inuse &= ~KVM_MIPS_FPU_FPU;
+	}
+	preempt_enable();
+}
+
+/* Save and disable FPU & MSA */
+void kvm_lose_fpu(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * FPU & MSA get disabled in root context (hardware) when it is disabled
+	 * in guest context (software), but the register state in the hardware
+	 * may still be in use. This is why we explicitly re-enable the hardware
+	 * before saving.
+	 */
+
+	preempt_disable();
+	if (cpu_has_msa && vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA) {
+		set_c0_config5(MIPS_CONF5_MSAEN);
+		enable_fpu_hazard();
+
+		__kvm_save_msa(&vcpu->arch);
+
+		/* Disable MSA & FPU */
+		disable_msa();
+		if (vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU)
+			clear_c0_status(ST0_CU1 | ST0_FR);
+		vcpu->arch.fpu_inuse &= ~(KVM_MIPS_FPU_FPU | KVM_MIPS_FPU_MSA);
+	} else if (vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU) {
+		set_c0_status(ST0_CU1);
+		enable_fpu_hazard();
+
+		__kvm_save_fpu(&vcpu->arch);
+		vcpu->arch.fpu_inuse &= ~KVM_MIPS_FPU_FPU;
+
+		/* Disable FPU */
+		clear_c0_status(ST0_CU1 | ST0_FR);
+	}
+	preempt_enable();
+}
+
+/*
+ * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are
+ * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP
+ * exception if cause bits are set in the value being written.
+ */
+static int kvm_mips_csr_die_notify(struct notifier_block *self,
+				   unsigned long cmd, void *ptr)
+{
+	struct die_args *args = (struct die_args *)ptr;
+	struct pt_regs *regs = args->regs;
+	unsigned long pc;
+
+	/* Only interested in FPE and MSAFPE */
+	if (cmd != DIE_FP && cmd != DIE_MSAFP)
+		return NOTIFY_DONE;
+
+	/* Return immediately if guest context isn't active */
+	if (!(current->flags & PF_VCPU))
+		return NOTIFY_DONE;
+
+	/* Should never get here from user mode */
+	BUG_ON(user_mode(regs));
+
+	pc = instruction_pointer(regs);
+	switch (cmd) {
+	case DIE_FP:
+		/* match 2nd instruction in __kvm_restore_fcsr */
+		if (pc != (unsigned long)&__kvm_restore_fcsr + 4)
+			return NOTIFY_DONE;
+		break;
+	case DIE_MSAFP:
+		/* match 2nd/3rd instruction in __kvm_restore_msacsr */
+		if (!cpu_has_msa ||
+		    pc < (unsigned long)&__kvm_restore_msacsr + 4 ||
+		    pc > (unsigned long)&__kvm_restore_msacsr + 8)
+			return NOTIFY_DONE;
+		break;
+	}
+
+	/* Move PC forward a little and continue executing */
+	instruction_pointer(regs) += 4;
+
+	return NOTIFY_STOP;
+}
+
+static struct notifier_block kvm_mips_csr_die_notifier = {
+	.notifier_call = kvm_mips_csr_die_notify,
+};
+
+int __init kvm_mips_init(void)
+{
+	int ret;
+
+	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+
+	if (ret)
+		return ret;
+
+	register_die_notifier(&kvm_mips_csr_die_notifier);
+
+	/*
+	 * On MIPS, kernel modules are executed from "mapped space", which
+	 * requires TLBs. The TLB handling code is statically linked with
+	 * the rest of the kernel (tlb.c) to avoid the possibility of
+	 * double faulting. The issue is that the TLB code references
+	 * routines that are part of the the KVM module, which are only
+	 * available once the module is loaded.
+	 */
+	kvm_mips_gfn_to_pfn = gfn_to_pfn;
+	kvm_mips_release_pfn_clean = kvm_release_pfn_clean;
+	kvm_mips_is_error_pfn = is_error_pfn;
+
+	return 0;
+}
+
+void __exit kvm_mips_exit(void)
+{
+	kvm_exit();
+
+	kvm_mips_gfn_to_pfn = NULL;
+	kvm_mips_release_pfn_clean = NULL;
+	kvm_mips_is_error_pfn = NULL;
+
+	unregister_die_notifier(&kvm_mips_csr_die_notifier);
+}
+
+module_init(kvm_mips_init);
+module_exit(kvm_mips_exit);
+
+EXPORT_TRACEPOINT_SYMBOL(kvm_exit);