v4.19.13 snapshot.
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
new file mode 100644
index 0000000..f7ea8e2
--- /dev/null
+++ b/arch/mips/kvm/mips.c
@@ -0,0 +1,1727 @@
+/*
+ * 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/bitops.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/kdebug.h>
+#include <linux/module.h>
+#include <linux/uaccess.h>
+#include <linux/vmalloc.h>
+#include <linux/sched/signal.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/pgalloc.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_unusable", 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 },
+#ifdef CONFIG_KVM_MIPS_VZ
+	{ "vz_gpsi",	  VCPU_STAT(vz_gpsi_exits),	 KVM_STAT_VCPU },
+	{ "vz_gsfc",	  VCPU_STAT(vz_gsfc_exits),	 KVM_STAT_VCPU },
+	{ "vz_hc",	  VCPU_STAT(vz_hc_exits),	 KVM_STAT_VCPU },
+	{ "vz_grr",	  VCPU_STAT(vz_grr_exits),	 KVM_STAT_VCPU },
+	{ "vz_gva",	  VCPU_STAT(vz_gva_exits),	 KVM_STAT_VCPU },
+	{ "vz_ghfc",	  VCPU_STAT(vz_ghfc_exits),	 KVM_STAT_VCPU },
+	{ "vz_gpa",	  VCPU_STAT(vz_gpa_exits),	 KVM_STAT_VCPU },
+	{ "vz_resvd",	  VCPU_STAT(vz_resvd_exits),	 KVM_STAT_VCPU },
+#endif
+	{ "halt_successful_poll", VCPU_STAT(halt_successful_poll), KVM_STAT_VCPU },
+	{ "halt_attempted_poll", VCPU_STAT(halt_attempted_poll), KVM_STAT_VCPU },
+	{ "halt_poll_invalid", VCPU_STAT(halt_poll_invalid), KVM_STAT_VCPU },
+	{ "halt_wakeup",  VCPU_STAT(halt_wakeup),	 KVM_STAT_VCPU },
+	{NULL}
+};
+
+bool kvm_trace_guest_mode_change;
+
+int kvm_guest_mode_change_trace_reg(void)
+{
+	kvm_trace_guest_mode_change = 1;
+	return 0;
+}
+
+void kvm_guest_mode_change_trace_unreg(void)
+{
+	kvm_trace_guest_mode_change = 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);
+}
+
+bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu)
+{
+	return false;
+}
+
+int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu)
+{
+	return 1;
+}
+
+int kvm_arch_hardware_enable(void)
+{
+	return kvm_mips_callbacks->hardware_enable();
+}
+
+void kvm_arch_hardware_disable(void)
+{
+	kvm_mips_callbacks->hardware_disable();
+}
+
+int kvm_arch_hardware_setup(void)
+{
+	return 0;
+}
+
+void kvm_arch_check_processor_compat(void *rtn)
+{
+	*(int *)rtn = 0;
+}
+
+int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
+{
+	switch (type) {
+#ifdef CONFIG_KVM_MIPS_VZ
+	case KVM_VM_MIPS_VZ:
+#else
+	case KVM_VM_MIPS_TE:
+#endif
+		break;
+	default:
+		/* Unsupported KVM type */
+		return -EINVAL;
+	};
+
+	/* Allocate page table to map GPA -> RPA */
+	kvm->arch.gpa_mm.pgd = kvm_pgd_alloc();
+	if (!kvm->arch.gpa_mm.pgd)
+		return -ENOMEM;
+
+	return 0;
+}
+
+bool kvm_arch_has_vcpu_debugfs(void)
+{
+	return false;
+}
+
+int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
+{
+	return 0;
+}
+
+void kvm_mips_free_vcpus(struct kvm *kvm)
+{
+	unsigned int i;
+	struct kvm_vcpu *vcpu;
+
+	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_free_gpa_pt(struct kvm *kvm)
+{
+	/* It should always be safe to remove after flushing the whole range */
+	WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0));
+	pgd_free(NULL, kvm->arch.gpa_mm.pgd);
+}
+
+void kvm_arch_destroy_vm(struct kvm *kvm)
+{
+	kvm_mips_free_vcpus(kvm);
+	kvm_mips_free_gpa_pt(kvm);
+}
+
+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;
+}
+
+void kvm_arch_flush_shadow_all(struct kvm *kvm)
+{
+	/* Flush whole GPA */
+	kvm_mips_flush_gpa_pt(kvm, 0, ~0);
+
+	/* Let implementation do the rest */
+	kvm_mips_callbacks->flush_shadow_all(kvm);
+}
+
+void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
+				   struct kvm_memory_slot *slot)
+{
+	/*
+	 * The slot has been made invalid (ready for moving or deletion), so we
+	 * need to ensure that it can no longer be accessed by any guest VCPUs.
+	 */
+
+	spin_lock(&kvm->mmu_lock);
+	/* Flush slot from GPA */
+	kvm_mips_flush_gpa_pt(kvm, slot->base_gfn,
+			      slot->base_gfn + slot->npages - 1);
+	/* Let implementation do the rest */
+	kvm_mips_callbacks->flush_shadow_memslot(kvm, slot);
+	spin_unlock(&kvm->mmu_lock);
+}
+
+int kvm_arch_prepare_memory_region(struct kvm *kvm,
+				   struct kvm_memory_slot *memslot,
+				   const struct kvm_userspace_memory_region *mem,
+				   enum kvm_mr_change change)
+{
+	return 0;
+}
+
+void kvm_arch_commit_memory_region(struct kvm *kvm,
+				   const struct kvm_userspace_memory_region *mem,
+				   const struct kvm_memory_slot *old,
+				   const struct kvm_memory_slot *new,
+				   enum kvm_mr_change change)
+{
+	int needs_flush;
+
+	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);
+
+	/*
+	 * If dirty page logging is enabled, write protect all pages in the slot
+	 * ready for dirty logging.
+	 *
+	 * There is no need to do this in any of the following cases:
+	 * CREATE:	No dirty mappings will already exist.
+	 * MOVE/DELETE:	The old mappings will already have been cleaned up by
+	 *		kvm_arch_flush_shadow_memslot()
+	 */
+	if (change == KVM_MR_FLAGS_ONLY &&
+	    (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) &&
+	     new->flags & KVM_MEM_LOG_DIRTY_PAGES)) {
+		spin_lock(&kvm->mmu_lock);
+		/* Write protect GPA page table entries */
+		needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn,
+					new->base_gfn + new->npages - 1);
+		/* Let implementation do the rest */
+		if (needs_flush)
+			kvm_mips_callbacks->flush_shadow_memslot(kvm, new);
+		spin_unlock(&kvm->mmu_lock);
+	}
+}
+
+static inline void dump_handler(const char *symbol, void *start, void *end)
+{
+	u32 *p;
+
+	pr_debug("LEAF(%s)\n", symbol);
+
+	pr_debug("\t.set push\n");
+	pr_debug("\t.set noreorder\n");
+
+	for (p = start; p < (u32 *)end; ++p)
+		pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p);
+
+	pr_debug("\t.set\tpop\n");
+
+	pr_debug("\tEND(%s)\n", symbol);
+}
+
+struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)
+{
+	int err, size;
+	void *gebase, *p, *handler, *refill_start, *refill_end;
+	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;
+
+	gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL);
+
+	if (!gebase) {
+		err = -ENOMEM;
+		goto out_uninit_cpu;
+	}
+	kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n",
+		  ALIGN(size, PAGE_SIZE), gebase);
+
+	/*
+	 * Check new ebase actually fits in CP0_EBase. The lack of a write gate
+	 * limits us to the low 512MB of physical address space. If the memory
+	 * we allocate is out of range, just give up now.
+	 */
+	if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) {
+		kvm_err("CP0_EBase.WG required for guest exception base %pK\n",
+			gebase);
+		err = -ENOMEM;
+		goto out_free_gebase;
+	}
+
+	/* Save new ebase */
+	vcpu->arch.guest_ebase = gebase;
+
+	/* Build guest exception vectors dynamically in unmapped memory */
+	handler = gebase + 0x2000;
+
+	/* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */
+	refill_start = gebase;
+	if (IS_ENABLED(CONFIG_KVM_MIPS_VZ) && IS_ENABLED(CONFIG_64BIT))
+		refill_start += 0x080;
+	refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler);
+
+	/* General Exception Entry point */
+	kvm_mips_build_exception(gebase + 0x180, handler);
+
+	/* 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));
+		kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING,
+					 handler);
+	}
+
+	/* General exit handler */
+	p = handler;
+	p = kvm_mips_build_exit(p);
+
+	/* Guest entry routine */
+	vcpu->arch.vcpu_run = p;
+	p = kvm_mips_build_vcpu_run(p);
+
+	/* Dump the generated code */
+	pr_debug("#include <asm/asm.h>\n");
+	pr_debug("#include <asm/regdef.h>\n");
+	pr_debug("\n");
+	dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p);
+	dump_handler("kvm_tlb_refill", refill_start, refill_end);
+	dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200);
+	dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run);
+
+	/* Invalidate the icache for these ranges */
+	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;
+	vcpu->arch.last_exec_cpu = -1;
+
+	return vcpu;
+
+out_free_gebase:
+	kfree(gebase);
+
+out_uninit_cpu:
+	kvm_vcpu_uninit(vcpu);
+
+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);
+
+	kvm_mmu_free_memory_caches(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 = -EINTR;
+
+	vcpu_load(vcpu);
+
+	kvm_sigset_activate(vcpu);
+
+	if (vcpu->mmio_needed) {
+		if (!vcpu->mmio_is_write)
+			kvm_mips_complete_mmio_load(vcpu, run);
+		vcpu->mmio_needed = 0;
+	}
+
+	if (run->immediate_exit)
+		goto out;
+
+	lose_fpu(1);
+
+	local_irq_disable();
+	guest_enter_irqoff();
+	trace_kvm_enter(vcpu);
+
+	/*
+	 * Make sure the read of VCPU requests in vcpu_run() callback is not
+	 * reordered ahead of the write to vcpu->mode, or we could miss a TLB
+	 * flush request while the requester sees the VCPU as outside of guest
+	 * mode and not needing an IPI.
+	 */
+	smp_store_mb(vcpu->mode, IN_GUEST_MODE);
+
+	r = kvm_mips_callbacks->vcpu_run(run, vcpu);
+
+	trace_kvm_out(vcpu);
+	guest_exit_irqoff();
+	local_irq_enable();
+
+out:
+	kvm_sigset_deactivate(vcpu);
+
+	vcpu_put(vcpu);
+	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 (swq_has_sleeper(&dvcpu->wq))
+		swake_up_one(&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,
+
+#ifndef CONFIG_CPU_MIPSR6
+	KVM_REG_MIPS_HI,
+	KVM_REG_MIPS_LO,
+#endif
+	KVM_REG_MIPS_PC,
+};
+
+static u64 kvm_mips_get_one_regs_fpu[] = {
+	KVM_REG_MIPS_FCR_IR,
+	KVM_REG_MIPS_FCR_CSR,
+};
+
+static u64 kvm_mips_get_one_regs_msa[] = {
+	KVM_REG_MIPS_MSA_IR,
+	KVM_REG_MIPS_MSA_CSR,
+};
+
+static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu)
+{
+	unsigned long ret;
+
+	ret = ARRAY_SIZE(kvm_mips_get_one_regs);
+	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
+		ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48;
+		/* odd doubles */
+		if (boot_cpu_data.fpu_id & MIPS_FPIR_F64)
+			ret += 16;
+	}
+	if (kvm_mips_guest_can_have_msa(&vcpu->arch))
+		ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32;
+	ret += kvm_mips_callbacks->num_regs(vcpu);
+
+	return ret;
+}
+
+static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices)
+{
+	u64 index;
+	unsigned int i;
+
+	if (copy_to_user(indices, kvm_mips_get_one_regs,
+			 sizeof(kvm_mips_get_one_regs)))
+		return -EFAULT;
+	indices += ARRAY_SIZE(kvm_mips_get_one_regs);
+
+	if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) {
+		if (copy_to_user(indices, kvm_mips_get_one_regs_fpu,
+				 sizeof(kvm_mips_get_one_regs_fpu)))
+			return -EFAULT;
+		indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu);
+
+		for (i = 0; i < 32; ++i) {
+			index = KVM_REG_MIPS_FPR_32(i);
+			if (copy_to_user(indices, &index, sizeof(index)))
+				return -EFAULT;
+			++indices;
+
+			/* skip odd doubles if no F64 */
+			if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64))
+				continue;
+
+			index = KVM_REG_MIPS_FPR_64(i);
+			if (copy_to_user(indices, &index, sizeof(index)))
+				return -EFAULT;
+			++indices;
+		}
+	}
+
+	if (kvm_mips_guest_can_have_msa(&vcpu->arch)) {
+		if (copy_to_user(indices, kvm_mips_get_one_regs_msa,
+				 sizeof(kvm_mips_get_one_regs_msa)))
+			return -EFAULT;
+		indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa);
+
+		for (i = 0; i < 32; ++i) {
+			index = KVM_REG_MIPS_VEC_128(i);
+			if (copy_to_user(indices, &index, sizeof(index)))
+				return -EFAULT;
+			++indices;
+		}
+	}
+
+	return kvm_mips_callbacks->copy_reg_indices(vcpu, indices);
+}
+
+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;
+#ifndef CONFIG_CPU_MIPSR6
+	case KVM_REG_MIPS_HI:
+		v = (long)vcpu->arch.hi;
+		break;
+	case KVM_REG_MIPS_LO:
+		v = (long)vcpu->arch.lo;
+		break;
+#endif
+	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;
+
+	/* registers to be handled specially */
+	default:
+		ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v);
+		if (ret)
+			return ret;
+		break;
+	}
+	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) ? -EFAULT : 0;
+	} 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) ? -EFAULT : 0;
+	} 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;
+#ifndef CONFIG_CPU_MIPSR6
+	case KVM_REG_MIPS_HI:
+		vcpu->arch.hi = v;
+		break;
+	case KVM_REG_MIPS_LO:
+		vcpu->arch.lo = v;
+		break;
+#endif
+	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;
+
+	/* registers to be handled specially */
+	default:
+		return kvm_mips_callbacks->set_one_reg(vcpu, reg, v);
+	}
+	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_async_ioctl(struct file *filp, unsigned int ioctl,
+			       unsigned long arg)
+{
+	struct kvm_vcpu *vcpu = filp->private_data;
+	void __user *argp = (void __user *)arg;
+
+	if (ioctl == KVM_INTERRUPT) {
+		struct kvm_mips_interrupt irq;
+
+		if (copy_from_user(&irq, argp, sizeof(irq)))
+			return -EFAULT;
+		kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
+			  irq.irq);
+
+		return kvm_vcpu_ioctl_interrupt(vcpu, &irq);
+	}
+
+	return -ENOIOCTLCMD;
+}
+
+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;
+
+	vcpu_load(vcpu);
+
+	switch (ioctl) {
+	case KVM_SET_ONE_REG:
+	case KVM_GET_ONE_REG: {
+		struct kvm_one_reg reg;
+
+		r = -EFAULT;
+		if (copy_from_user(&reg, argp, sizeof(reg)))
+			break;
+		if (ioctl == KVM_SET_ONE_REG)
+			r = kvm_mips_set_reg(vcpu, &reg);
+		else
+			r = kvm_mips_get_reg(vcpu, &reg);
+		break;
+	}
+	case KVM_GET_REG_LIST: {
+		struct kvm_reg_list __user *user_list = argp;
+		struct kvm_reg_list reg_list;
+		unsigned n;
+
+		r = -EFAULT;
+		if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
+			break;
+		n = reg_list.n;
+		reg_list.n = kvm_mips_num_regs(vcpu);
+		if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
+			break;
+		r = -E2BIG;
+		if (n < reg_list.n)
+			break;
+		r = kvm_mips_copy_reg_indices(vcpu, user_list->reg);
+		break;
+	}
+	case KVM_ENABLE_CAP: {
+		struct kvm_enable_cap cap;
+
+		r = -EFAULT;
+		if (copy_from_user(&cap, argp, sizeof(cap)))
+			break;
+		r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap);
+		break;
+	}
+	default:
+		r = -ENOIOCTLCMD;
+	}
+
+	vcpu_put(vcpu);
+	return r;
+}
+
+/**
+ * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
+ * @kvm: kvm instance
+ * @log: slot id and address to which we copy the log
+ *
+ * Steps 1-4 below provide general overview of dirty page logging. See
+ * kvm_get_dirty_log_protect() function description for additional details.
+ *
+ * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
+ * always flush the TLB (step 4) even if previous step failed  and the dirty
+ * bitmap may be corrupt. Regardless of previous outcome the KVM logging API
+ * does not preclude user space subsequent dirty log read. Flushing TLB ensures
+ * writes will be marked dirty for next log read.
+ *
+ *   1. Take a snapshot of the bit and clear it if needed.
+ *   2. Write protect the corresponding page.
+ *   3. Copy the snapshot to the userspace.
+ *   4. Flush TLB's if needed.
+ */
+int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
+{
+	struct kvm_memslots *slots;
+	struct kvm_memory_slot *memslot;
+	bool is_dirty = false;
+	int r;
+
+	mutex_lock(&kvm->slots_lock);
+
+	r = kvm_get_dirty_log_protect(kvm, log, &is_dirty);
+
+	if (is_dirty) {
+		slots = kvm_memslots(kvm);
+		memslot = id_to_memslot(slots, log->slot);
+
+		/* Let implementation handle TLB/GVA invalidation */
+		kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot);
+	}
+
+	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;
+}
+
+vm_fault_t 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:
+	case KVM_CAP_READONLY_MEM:
+	case KVM_CAP_SYNC_MMU:
+	case KVM_CAP_IMMEDIATE_EXIT:
+		r = 1;
+		break;
+	case KVM_CAP_NR_VCPUS:
+		r = num_online_cpus();
+		break;
+	case KVM_CAP_MAX_VCPUS:
+		r = KVM_MAX_VCPUS;
+		break;
+	case KVM_CAP_MIPS_FPU:
+		/* We don't handle systems with inconsistent cpu_has_fpu */
+		r = !!raw_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 = kvm_mips_callbacks->check_extension(kvm, ext);
+		break;
+	}
+	return r;
+}
+
+int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
+{
+	return kvm_mips_pending_timer(vcpu) ||
+		kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI;
+}
+
+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%08x, Cause: 0x%08x\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;
+
+	vcpu_load(vcpu);
+
+	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;
+
+	vcpu_put(vcpu);
+	return 0;
+}
+
+int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
+{
+	int i;
+
+	vcpu_load(vcpu);
+
+	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;
+
+	vcpu_put(vcpu);
+	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 (swq_has_sleeper(&vcpu->wq))
+		swake_up_one(&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)
+{
+	int err;
+
+	err = kvm_mips_callbacks->vcpu_init(vcpu);
+	if (err)
+		return err;
+
+	hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC,
+		     HRTIMER_MODE_REL);
+	vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup;
+	return 0;
+}
+
+void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)
+{
+	kvm_mips_callbacks->vcpu_uninit(vcpu);
+}
+
+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)
+{
+	u32 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)
+{
+	u32 cause = vcpu->arch.host_cp0_cause;
+	u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
+	u32 __user *opc = (u32 __user *) vcpu->arch.pc;
+	unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
+	enum emulation_result er = EMULATE_DONE;
+	u32 inst;
+	int ret = RESUME_GUEST;
+
+	vcpu->mode = OUTSIDE_GUEST_MODE;
+
+	/* re-enable HTW before enabling interrupts */
+	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
+		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);
+	trace_kvm_exit(vcpu, exccode);
+
+	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
+		/*
+		 * 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 EXCCODE_INT:
+		kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc);
+
+		++vcpu->stat.int_exits;
+
+		if (need_resched())
+			cond_resched();
+
+		ret = RESUME_GUEST;
+		break;
+
+	case EXCCODE_CPU:
+		kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc);
+
+		++vcpu->stat.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 EXCCODE_MOD:
+		++vcpu->stat.tlbmod_exits;
+		ret = kvm_mips_callbacks->handle_tlb_mod(vcpu);
+		break;
+
+	case EXCCODE_TLBS:
+		kvm_debug("TLB ST fault:  cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n",
+			  cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc,
+			  badvaddr);
+
+		++vcpu->stat.tlbmiss_st_exits;
+		ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu);
+		break;
+
+	case EXCCODE_TLBL:
+		kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
+			  cause, opc, badvaddr);
+
+		++vcpu->stat.tlbmiss_ld_exits;
+		ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu);
+		break;
+
+	case EXCCODE_ADES:
+		++vcpu->stat.addrerr_st_exits;
+		ret = kvm_mips_callbacks->handle_addr_err_st(vcpu);
+		break;
+
+	case EXCCODE_ADEL:
+		++vcpu->stat.addrerr_ld_exits;
+		ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu);
+		break;
+
+	case EXCCODE_SYS:
+		++vcpu->stat.syscall_exits;
+		ret = kvm_mips_callbacks->handle_syscall(vcpu);
+		break;
+
+	case EXCCODE_RI:
+		++vcpu->stat.resvd_inst_exits;
+		ret = kvm_mips_callbacks->handle_res_inst(vcpu);
+		break;
+
+	case EXCCODE_BP:
+		++vcpu->stat.break_inst_exits;
+		ret = kvm_mips_callbacks->handle_break(vcpu);
+		break;
+
+	case EXCCODE_TR:
+		++vcpu->stat.trap_inst_exits;
+		ret = kvm_mips_callbacks->handle_trap(vcpu);
+		break;
+
+	case EXCCODE_MSAFPE:
+		++vcpu->stat.msa_fpe_exits;
+		ret = kvm_mips_callbacks->handle_msa_fpe(vcpu);
+		break;
+
+	case EXCCODE_FPE:
+		++vcpu->stat.fpe_exits;
+		ret = kvm_mips_callbacks->handle_fpe(vcpu);
+		break;
+
+	case EXCCODE_MSADIS:
+		++vcpu->stat.msa_disabled_exits;
+		ret = kvm_mips_callbacks->handle_msa_disabled(vcpu);
+		break;
+
+	case EXCCODE_GE:
+		/* defer exit accounting to handler */
+		ret = kvm_mips_callbacks->handle_guest_exit(vcpu);
+		break;
+
+	default:
+		if (cause & CAUSEF_BD)
+			opc += 1;
+		inst = 0;
+		kvm_get_badinstr(opc, vcpu, &inst);
+		kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x  BadVaddr: %#lx Status: %#x\n",
+			exccode, opc, inst, 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 (ret == RESUME_GUEST)
+		kvm_vz_acquire_htimer(vcpu);
+
+	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, KVM_TRACE_EXIT_SIGNAL);
+		}
+	}
+
+	if (ret == RESUME_GUEST) {
+		trace_kvm_reenter(vcpu);
+
+		/*
+		 * Make sure the read of VCPU requests in vcpu_reenter()
+		 * callback is not reordered ahead of the write to vcpu->mode,
+		 * or we could miss a TLB flush request while the requester sees
+		 * the VCPU as outside of guest mode and not needing an IPI.
+		 */
+		smp_store_mb(vcpu->mode, IN_GUEST_MODE);
+
+		kvm_mips_callbacks->vcpu_reenter(run, vcpu);
+
+		/*
+		 * 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 */
+	if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ))
+		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.aux_inuse & KVM_MIPS_AUX_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.aux_inuse & KVM_MIPS_AUX_FPU)) {
+		__kvm_restore_fpu(&vcpu->arch);
+		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU);
+	} else {
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_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.aux_inuse & (KVM_MIPS_AUX_FPU |
+				KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_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.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) {
+	case KVM_MIPS_AUX_FPU:
+		/*
+		 * Guest FPU state already loaded, only restore upper MSA state
+		 */
+		__kvm_restore_msa_upper(&vcpu->arch);
+		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA);
+		break;
+	case 0:
+		/* Neither FPU or MSA already active, restore full MSA state */
+		__kvm_restore_msa(&vcpu->arch);
+		vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA;
+		if (kvm_mips_guest_has_fpu(&vcpu->arch))
+			vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU;
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE,
+			      KVM_TRACE_AUX_FPU_MSA);
+		break;
+	default:
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA);
+		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.aux_inuse & KVM_MIPS_AUX_MSA) {
+		disable_msa();
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA);
+		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA;
+	}
+	if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
+		clear_c0_status(ST0_CU1 | ST0_FR);
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU);
+		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
+	}
+	preempt_enable();
+}
+
+/* Save and disable FPU & MSA */
+void kvm_lose_fpu(struct kvm_vcpu *vcpu)
+{
+	/*
+	 * With T&E, 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.aux_inuse & KVM_MIPS_AUX_MSA) {
+		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
+			set_c0_config5(MIPS_CONF5_MSAEN);
+			enable_fpu_hazard();
+		}
+
+		__kvm_save_msa(&vcpu->arch);
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA);
+
+		/* Disable MSA & FPU */
+		disable_msa();
+		if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
+			clear_c0_status(ST0_CU1 | ST0_FR);
+			disable_fpu_hazard();
+		}
+		vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA);
+	} else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) {
+		if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) {
+			set_c0_status(ST0_CU1);
+			enable_fpu_hazard();
+		}
+
+		__kvm_save_fpu(&vcpu->arch);
+		vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU;
+		trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU);
+
+		/* Disable FPU */
+		clear_c0_status(ST0_CU1 | ST0_FR);
+		disable_fpu_hazard();
+	}
+	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,
+};
+
+static int __init kvm_mips_init(void)
+{
+	int ret;
+
+	ret = kvm_mips_entry_setup();
+	if (ret)
+		return ret;
+
+	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);
+
+	if (ret)
+		return ret;
+
+	register_die_notifier(&kvm_mips_csr_die_notifier);
+
+	return 0;
+}
+
+static void __exit kvm_mips_exit(void)
+{
+	kvm_exit();
+
+	unregister_die_notifier(&kvm_mips_csr_die_notifier);
+}
+
+module_init(kvm_mips_init);
+module_exit(kvm_mips_exit);
+
+EXPORT_TRACEPOINT_SYMBOL(kvm_exit);