- 根目录:
- arch
- mips
- kvm
- mips.c
/*
* 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(®, argp, sizeof(reg)))
return -EFAULT;
if (ioctl == KVM_SET_ONE_REG)
return kvm_mips_set_reg(vcpu, ®);
else
return kvm_mips_get_reg(vcpu, ®);
}
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(®_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, ®_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 = &kvm->memslots->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);