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Commit 669e846e authored by Sanjay Lal's avatar Sanjay Lal Committed by Ralf Baechle
Browse files

KVM/MIPS32: MIPS arch specific APIs for KVM 



- Implements the arch specific APIs for KVM, some are stubs for MIPS
- kvm_mips_handle_exit(): Main 'C' distpatch routine for handling exceptions while in "Guest" mode.
- Also implements in-kernel timer interrupt support for the guest.

Signed-off-by: default avatarSanjay Lal <sanjayl@kymasys.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: default avatarRalf Baechle <ralf@linux-mips.org>
parent b680f70f

arch/mips/kvm/kvm_mips.c

0 → 100644
+958 −0
Original line number Diff line number Diff line 
/*

 * 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/module.h>

#include <linux/vmalloc.h>

#include <linux/fs.h>

#include <linux/bootmem.h>

#include <asm/page.h>

#include <asm/cacheflush.h>

#include <asm/mmu_context.h>



#include <linux/kvm_host.h>



#include "kvm_mips_int.h"

#include "kvm_mips_comm.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), KVM_STAT_VCPU

struct kvm_stats_debugfs_item debugfs_entries[] = {

	{ "wait", VCPU_STAT(wait_exits) },

	{ "cache", VCPU_STAT(cache_exits) },

	{ "signal", VCPU_STAT(signal_exits) },

	{ "interrupt", VCPU_STAT(int_exits) },

	{ "cop_unsuable", VCPU_STAT(cop_unusable_exits) },

	{ "tlbmod", VCPU_STAT(tlbmod_exits) },

	{ "tlbmiss_ld", VCPU_STAT(tlbmiss_ld_exits) },

	{ "tlbmiss_st", VCPU_STAT(tlbmiss_st_exits) },

	{ "addrerr_st", VCPU_STAT(addrerr_st_exits) },

	{ "addrerr_ld", VCPU_STAT(addrerr_ld_exits) },

	{ "syscall", VCPU_STAT(syscall_exits) },

	{ "resvd_inst", VCPU_STAT(resvd_inst_exits) },

	{ "break_inst", VCPU_STAT(break_inst_exits) },

	{ "flush_dcache", VCPU_STAT(flush_dcache_exits) },

	{ "halt_wakeup", VCPU_STAT(halt_wakeup) },

	{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;

}



gfn_t unalias_gfn(struct kvm *kvm, gfn_t gfn)

{

	return gfn;

}



/* 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 *garbage)

{

	return 0;

}



void kvm_arch_hardware_disable(void *garbage)

{

}



int kvm_arch_hardware_setup(void)

{

	return 0;

}



void kvm_arch_hardware_unsetup(void)

{

}



void kvm_arch_check_processor_compat(void *rtn)

{

	int *r = (int *)rtn;

	*r = 0;

	return;

}



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_info("%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]);

	}



	if (kvm->arch.guest_pmap)

		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);

}



void kvm_arch_sync_events(struct kvm *kvm)

{

}



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_info("%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 -EINVAL;

}



void kvm_arch_free_memslot(struct kvm_memory_slot *free,

			   struct kvm_memory_slot *dont)

{

}



int kvm_arch_create_memslot(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_memory_slot old,

				   struct kvm_userspace_memory_region *mem,

				   bool user_alloc)

{

	return 0;

}



void kvm_arch_commit_memory_region(struct kvm *kvm,

				   struct kvm_userspace_memory_region *mem,

				   struct kvm_memory_slot old, bool user_alloc)

{

	unsigned long npages = 0;

	int i, err = 0;



	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");

				err = -ENOMEM;

				goto out;

			}



			kvm_info

			    ("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;

			}

		}

	}

out:

	return;

}



void kvm_arch_flush_shadow_all(struct kvm *kvm)

{

}



void kvm_arch_flush_shadow_memslot(struct kvm *kvm,

				   struct kvm_memory_slot *slot)

{

}



void kvm_arch_flush_shadow(struct kvm *kvm)

{

}



struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id)

{

	extern char mips32_exception[], mips32_exceptionEnd[];

	extern char mips32_GuestException[], mips32_GuestExceptionEnd[];

	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_info("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 = 0x200;

	}



	/* 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_info("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_info("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 */

	mips32_SyncICache((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_info("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_emulate_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);



	if (vcpu->arch.guest_ebase)

		kfree(vcpu->arch.guest_ebase);



	if (vcpu->arch.kseg0_commpage)

		kfree(vcpu->arch.kseg0_commpage);



}



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 -EINVAL;

}



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;

	}



	/* Check if we have any exceptions/interrupts pending */

	kvm_mips_deliver_interrupts(vcpu,

				    kvm_read_c0_guest_cause(vcpu->arch.cop0));



	local_irq_disable();

	kvm_guest_enter();



	r = __kvm_mips_vcpu_run(run, vcpu);



	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 -EINVAL;

}



int

kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu,

				struct kvm_mp_state *mp_state)

{

	return -EINVAL;

}



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;

	int intr;



	switch (ioctl) {

	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;



			intr = (int)irq.irq;



			kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,

				  irq.irq);



			r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);

			break;

		}

	default:

		r = -EINVAL;

	}



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 = &kvm->memslots->memslots[log->slot];



		ga = memslot->base_gfn << PAGE_SHIFT;

		ga_end = ga + (memslot->npages << PAGE_SHIFT);



		printk("%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 = -EINVAL;

	}



	return r;

}



int kvm_arch_init(void *opaque)

{

	int ret;



	if (kvm_mips_callbacks) {

		kvm_err("kvm: module already exists\n");

		return -EEXIST;

	}



	ret = kvm_mips_emulation_init(&kvm_mips_callbacks);



	return ret;

}



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 -ENOTSUPP;

}



int

kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs)

{

	return -ENOTSUPP;

}



int kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu)

{

	return 0;

}



int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)

{

	return -ENOTSUPP;

}



int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)

{

	return -ENOTSUPP;

}



int kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf)

{

	return VM_FAULT_SIGBUS;

}



int kvm_dev_ioctl_check_extension(long ext)

{

	int r;



	switch (ext) {

	case KVM_CAP_COALESCED_MMIO:

		r = KVM_COALESCED_MMIO_PAGE_OFFSET;

		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;



	printk("VCPU Register Dump:\n");

	printk("\tpc = 0x%08lx\n", vcpu->arch.pc);;

	printk("\texceptions: %08lx\n", vcpu->arch.pending_exceptions);



	for (i = 0; i < 32; i += 4) {

		printk("\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]);

	}

	printk("\thi: 0x%08lx\n", vcpu->arch.hi);

	printk("\tlo: 0x%08lx\n", vcpu->arch.lo);



	cop0 = vcpu->arch.cop0;

	printk("\tStatus: 0x%08lx, Cause: 0x%08lx\n",

	       kvm_read_c0_guest_status(cop0), kvm_read_c0_guest_cause(cop0));



	printk("\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 = 0; i < 32; i++)

		vcpu->arch.gprs[i] = regs->gprs[i];



	vcpu->arch.hi = regs->hi;

	vcpu->arch.lo = regs->lo;

	vcpu->arch.pc = regs->pc;



	return kvm_mips_callbacks->vcpu_ioctl_set_regs(vcpu, regs);

}



int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)

{

	int i;



	for (i = 0; i < 32; i++)

		regs->gprs[i] = vcpu->arch.gprs[i];



	regs->hi = vcpu->arch.hi;

	regs->lo = vcpu->arch.lo;

	regs->pc = vcpu->arch.pc;



	return kvm_mips_callbacks->vcpu_ioctl_get_regs(vcpu, regs);

}



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.

 */

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);

	hrtimer_forward_now(&vcpu->arch.comparecount_timer,

			    ktime_set(0, MS_TO_NS(10)));

	return HRTIMER_RESTART;

}



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;

	kvm_mips_init_shadow_tlb(vcpu);

	return 0;

}



void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu)

{

	return;

}



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_fpu)

		status |= (ST0_CU1);



	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;



	/* 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;



	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);

		}

	}



	return ret;

}



int __init kvm_mips_init(void)

{

	int ret;



	ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE);



	if (ret)

		return ret;



	/* 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 (kvm_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;



	pr_info("KVM/MIPS Initialized\n");

	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;



	pr_info("KVM/MIPS unloaded\n");

}



module_init(kvm_mips_init);

module_exit(kvm_mips_exit);



EXPORT_TRACEPOINT_SYMBOL(kvm_exit);

arch/mips/kvm/trace.h

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Original line number Diff line number Diff line 
/*

* 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.

*

* Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.

* Authors: Sanjay Lal <sanjayl@kymasys.com>

*/



#if !defined(_TRACE_KVM_H) || defined(TRACE_HEADER_MULTI_READ)

#define _TRACE_KVM_H



#include <linux/tracepoint.h>



#undef TRACE_SYSTEM

#define TRACE_SYSTEM kvm

#define TRACE_INCLUDE_PATH .

#define TRACE_INCLUDE_FILE trace



/*

 * Tracepoints for VM eists

 */

extern char *kvm_mips_exit_types_str[MAX_KVM_MIPS_EXIT_TYPES];



TRACE_EVENT(kvm_exit,

	    TP_PROTO(struct kvm_vcpu *vcpu, unsigned int reason),

	    TP_ARGS(vcpu, reason),

	    TP_STRUCT__entry(

			__field(struct kvm_vcpu *, vcpu)

			__field(unsigned int, reason)

	    ),



	    TP_fast_assign(

			__entry->vcpu = vcpu;

			__entry->reason = reason;

	    ),



	    TP_printk("[%s]PC: 0x%08lx",

		      kvm_mips_exit_types_str[__entry->reason],

		      __entry->vcpu->arch.pc)

);



#endif /* _TRACE_KVM_H */



/* This part must be outside protection */

#include <trace/define_trace.h>