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linux/arch/mips/kvm/mips.c
James Hogan f798217dfd KVM: MIPS: Don't leak FPU/DSP to guest 
The FPU and DSP are enabled via the CP0 Status CU1 and MX bits by
kvm_mips_set_c0_status() on a guest exit, presumably in case there is
active state that needs saving if pre-emption occurs. However neither of
these bits are cleared again when returning to the guest.

This effectively gives the guest access to the FPU/DSP hardware after
the first guest exit even though it is not aware of its presence,
allowing FP instructions in guest user code to intermittently actually
execute instead of trapping into the guest OS for emulation. It will
then read & manipulate the hardware FP registers which technically
belong to the user process (e.g. QEMU), or are stale from another user
process. It can also crash the guest OS by causing an FP exception, for
which a guest exception handler won't have been registered.

First lets save and disable the FPU (and MSA) state with lose_fpu(1)
before entering the guest. This simplifies the problem, especially for
when guest FPU/MSA support is added in the future, and prevents FR=1 FPU
state being live when the FR bit gets cleared for the guest, which
according to the architecture causes the contents of the FPU and vector
registers to become UNPREDICTABLE.

We can then safely remove the enabling of the FPU in
kvm_mips_set_c0_status(), since there should never be any active FPU or
MSA state to save at pre-emption, which should plug the FPU leak.

DSP state is always live rather than being lazily restored, so for that
it is simpler to just clear the MX bit again when re-entering the guest.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Sanjay Lal <sanjayl@kymasys.com>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Cc: <stable@vger.kernel.org> # v3.10+: 044f0f03ec: MIPS: KVM: Deliver guest interrupts
Cc: <stable@vger.kernel.org> # v3.10+
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2015-02-04 18:32:14 +01:00

1194 lines
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/*
* 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/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 },
{ "flush_dcache", VCPU_STAT(flush_dcache_exits), 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_CONFIG,
KVM_REG_MIPS_CP0_CONFIG1,
KVM_REG_MIPS_CP0_CONFIG2,
KVM_REG_MIPS_CP0_CONFIG3,
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;
int ret;
s64 v;
switch (reg->id) {
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;
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_ERROREPC:
v = (long)kvm_read_c0_guest_errorepc(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_CONFIG7:
v = (long)kvm_read_c0_guest_config7(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 {
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;
u64 v;
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 {
return -EINVAL;
}
switch (reg->id) {
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;
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_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_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;
}
long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl,
unsigned long arg)
{
struct kvm_vcpu *vcpu = filp->private_data;
void __user *argp = (void __user *)arg;
long r;
switch (ioctl) {
case KVM_SET_ONE_REG:
case KVM_GET_ONE_REG: {
struct kvm_one_reg reg;
if (copy_from_user(&reg, argp, sizeof(reg)))
return -EFAULT;
if (ioctl == KVM_SET_ONE_REG)
return kvm_mips_set_reg(vcpu, &reg);
else
return kvm_mips_get_reg(vcpu, &reg);
}
case KVM_GET_REG_LIST: {
struct kvm_reg_list __user *user_list = argp;
u64 __user *reg_dest;
struct kvm_reg_list reg_list;
unsigned n;
if (copy_from_user(&reg_list, user_list, sizeof(reg_list)))
return -EFAULT;
n = reg_list.n;
reg_list.n = ARRAY_SIZE(kvm_mips_get_one_regs);
if (copy_to_user(user_list, &reg_list, sizeof(reg_list)))
return -EFAULT;
if (n < reg_list.n)
return -E2BIG;
reg_dest = user_list->reg;
if (copy_to_user(reg_dest, kvm_mips_get_one_regs,
sizeof(kvm_mips_get_one_regs)))
return -EFAULT;
return 0;
}
case KVM_NMI:
/* Treat the NMI as a CPU reset */
r = kvm_mips_reset_vcpu(vcpu);
break;
case KVM_INTERRUPT:
{
struct kvm_mips_interrupt irq;
r = -EFAULT;
if (copy_from_user(&irq, argp, sizeof(irq)))
goto out;
kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__,
irq.irq);
r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
break;
}
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:
r = 1;
break;
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;
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;
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);
}
}
/* Disable HTW before returning to guest or host */
htw_stop();
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 (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);
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