/*
* 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: Deliver/Emulate exceptions to the guest kernel
*
* 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/kvm_host.h>
#include <linux/uaccess.h>
#include <linux/vmalloc.h>
#include <asm/mmu_context.h>
#include <asm/pgalloc.h>
#include "interrupt.h"
static gpa_t kvm_trap_emul_gva_to_gpa_cb(gva_t gva)
{
gpa_t gpa;
gva_t kseg = KSEGX(gva);
if ((kseg == CKSEG0) || (kseg == CKSEG1))
gpa = CPHYSADDR(gva);
else {
kvm_err("%s: cannot find GPA for GVA: %#lx\n", __func__, gva);
kvm_mips_dump_host_tlbs();
gpa = KVM_INVALID_ADDR;
}
kvm_debug("%s: gva %#lx, gpa: %#llx\n", __func__, gva, gpa);
return gpa;
}
static int kvm_trap_emul_handle_cop_unusable(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_run *run = vcpu->run;
u32 __user *opc = (u32 __user *) vcpu->arch.pc;
u32 cause = vcpu->arch.host_cp0_cause;
enum emulation_result er = EMULATE_DONE;
int ret = RESUME_GUEST;
if (((cause & CAUSEF_CE) >> CAUSEB_CE) == 1) {
/* FPU Unusable */
if (!kvm_mips_guest_has_fpu(&vcpu->arch) ||
(kvm_read_c0_guest_status(cop0) & ST0_CU1) == 0) {
/*
* Unusable/no FPU in guest:
* deliver guest COP1 Unusable Exception
*/
er = kvm_mips_emulate_fpu_exc(cause, opc, run, vcpu);
} else {
/* Restore FPU state */
kvm_own_fpu(vcpu);
er = EMULATE_DONE;
}
} else {
er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
}
switch (er) {
case EMULATE_DONE:
ret = RESUME_GUEST;
break;
case EMULATE_FAIL:
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
break;
case EMULATE_WAIT:
run->exit_reason = KVM_EXIT_INTR;
ret = RESUME_HOST;
break;
default:
BUG();
}
return ret;
}
static int kvm_trap_emul_handle_tlb_mod(struct kvm_vcpu *vcpu)
{
struct kvm_run *run = vcpu->run;
u32 __user *opc = (u32 __user *) vcpu->arch.pc;
unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
u32 cause = vcpu->arch.host_cp0_cause;
enum emulation_result er = EMULATE_DONE;
int ret = RESUME_GUEST;
if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
|| KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
kvm_debug("USER/KSEG23 ADDR TLB MOD fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
cause, opc, badvaddr);
er = kvm_mips_handle_tlbmod(cause, opc, run, vcpu);
if (er == EMULATE_DONE)
ret = RESUME_GUEST;
else {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
} else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
/*
* XXXKYMA: The guest kernel does not expect to get this fault
* when we are not using HIGHMEM. Need to address this in a
* HIGHMEM kernel
*/
kvm_err("TLB MOD fault not handled, cause %#x, PC: %p, BadVaddr: %#lx\n",
cause, opc, badvaddr);
kvm_mips_dump_host_tlbs();
kvm_arch_vcpu_dump_regs(vcpu);
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
} else {
kvm_err("Illegal TLB Mod fault address , cause %#x, PC: %p, BadVaddr: %#lx\n",
cause, opc, badvaddr);
kvm_mips_dump_host_tlbs();
kvm_arch_vcpu_dump_regs(vcpu);
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
return ret;
}
static int kvm_trap_emul_handle_tlb_miss(struct kvm_vcpu *vcpu, bool store)
{
struct kvm_run *run = vcpu->run;
u32 __user *opc = (u32 __user *) vcpu->arch.pc;