linux-stable/arch/mips/kvm/trap_emul.c
James Hogan 654229a024 KVM: MIPS/T&E: Move CP0 register access into T&E
Access to various CP0 registers via the KVM register access API needs to
be implementation specific to allow restrictions to be made on changes,
for example when VZ guest registers aren't present, so move them all
into trap_emul.c in preparation for VZ.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
2017-02-03 15:21:30 +00:00

1221 lines
33 KiB
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: 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);
gva_t gkseg = KVM_GUEST_KSEGX(gva);
if ((kseg == CKSEG0) || (kseg == CKSEG1))
gpa = CPHYSADDR(gva);
else if (gkseg == KVM_GUEST_KSEG0)
gpa = KVM_GUEST_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_mips_bad_load(u32 cause, u32 *opc, struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
enum emulation_result er;
union mips_instruction inst;
int err;
/* A code fetch fault doesn't count as an MMIO */
if (kvm_is_ifetch_fault(&vcpu->arch)) {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
return RESUME_HOST;
}
/* Fetch the instruction. */
if (cause & CAUSEF_BD)
opc += 1;
err = kvm_get_badinstr(opc, vcpu, &inst.word);
if (err) {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
return RESUME_HOST;
}
/* Emulate the load */
er = kvm_mips_emulate_load(inst, cause, run, vcpu);
if (er == EMULATE_FAIL) {
kvm_err("Emulate load from MMIO space failed\n");
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
} else {
run->exit_reason = KVM_EXIT_MMIO;
}
return RESUME_HOST;
}
static int kvm_mips_bad_store(u32 cause, u32 *opc, struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
enum emulation_result er;
union mips_instruction inst;
int err;
/* Fetch the instruction. */
if (cause & CAUSEF_BD)
opc += 1;
err = kvm_get_badinstr(opc, vcpu, &inst.word);
if (err) {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
return RESUME_HOST;
}
/* Emulate the store */
er = kvm_mips_emulate_store(inst, cause, run, vcpu);
if (er == EMULATE_FAIL) {
kvm_err("Emulate store to MMIO space failed\n");
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
} else {
run->exit_reason = KVM_EXIT_MMIO;
}
return RESUME_HOST;
}
static int kvm_mips_bad_access(u32 cause, u32 *opc, struct kvm_run *run,
struct kvm_vcpu *vcpu, bool store)
{
if (store)
return kvm_mips_bad_store(cause, opc, run, vcpu);
else
return kvm_mips_bad_load(cause, opc, run, vcpu);
}
static int kvm_trap_emul_handle_tlb_mod(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;
unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
u32 cause = vcpu->arch.host_cp0_cause;
struct kvm_mips_tlb *tlb;
unsigned long entryhi;
int index;
if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
|| KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
/*
* First find the mapping in the guest TLB. If the failure to
* write was due to the guest TLB, it should be up to the guest
* to handle it.
*/
entryhi = (badvaddr & VPN2_MASK) |
(kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID);
index = kvm_mips_guest_tlb_lookup(vcpu, entryhi);
/*
* These should never happen.
* They would indicate stale host TLB entries.
*/
if (unlikely(index < 0)) {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
return RESUME_HOST;
}
tlb = vcpu->arch.guest_tlb + index;
if (unlikely(!TLB_IS_VALID(*tlb, badvaddr))) {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
return RESUME_HOST;
}
/*
* Guest entry not dirty? That would explain the TLB modified
* exception. Relay that on to the guest so it can handle it.
*/
if (!TLB_IS_DIRTY(*tlb, badvaddr)) {
kvm_mips_emulate_tlbmod(cause, opc, run, vcpu);
return RESUME_GUEST;
}
if (kvm_mips_handle_mapped_seg_tlb_fault(vcpu, tlb, badvaddr,
true))
/* Not writable, needs handling as MMIO */
return kvm_mips_bad_store(cause, opc, run, vcpu);
return RESUME_GUEST;
} else if (KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG0) {
if (kvm_mips_handle_kseg0_tlb_fault(badvaddr, vcpu, true) < 0)
/* Not writable, needs handling as MMIO */
return kvm_mips_bad_store(cause, opc, run, vcpu);
return RESUME_GUEST;
} else {
/* host kernel addresses are all handled as MMIO */
return kvm_mips_bad_store(cause, opc, run, vcpu);
}
}
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;
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 (((badvaddr & PAGE_MASK) == KVM_GUEST_COMMPAGE_ADDR)
&& KVM_GUEST_KERNEL_MODE(vcpu)) {
if (kvm_mips_handle_commpage_tlb_fault(badvaddr, vcpu) < 0) {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
} else if (KVM_GUEST_KSEGX(badvaddr) < KVM_GUEST_KSEG0
|| KVM_GUEST_KSEGX(badvaddr) == KVM_GUEST_KSEG23) {
kvm_debug("USER ADDR TLB %s fault: cause %#x, PC: %p, BadVaddr: %#lx\n",
store ? "ST" : "LD", cause, opc, badvaddr);
/*
* User Address (UA) fault, this could happen if
* (1) TLB entry not present/valid in both Guest and shadow host
* TLBs, in this case we pass on the fault to the guest
* kernel and let it handle it.
* (2) TLB entry is present in the Guest TLB but not in the
* shadow, in this case we inject the TLB from the Guest TLB
* into the shadow host TLB
*/
er = kvm_mips_handle_tlbmiss(cause, opc, run, vcpu, store);
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) {
/*
* All KSEG0 faults are handled by KVM, as the guest kernel does
* not expect to ever get them
*/
if (kvm_mips_handle_kseg0_tlb_fault(badvaddr, vcpu, store) < 0)
ret = kvm_mips_bad_access(cause, opc, run, vcpu, store);
} else if (KVM_GUEST_KERNEL_MODE(vcpu)
&& (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1)) {
/*
* With EVA we may get a TLB exception instead of an address
* error when the guest performs MMIO to KSeg1 addresses.
*/
ret = kvm_mips_bad_access(cause, opc, run, vcpu, store);
} else {
kvm_err("Illegal TLB %s fault address , cause %#x, PC: %p, BadVaddr: %#lx\n",
store ? "ST" : "LD", 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_st_miss(struct kvm_vcpu *vcpu)
{
return kvm_trap_emul_handle_tlb_miss(vcpu, true);
}
static int kvm_trap_emul_handle_tlb_ld_miss(struct kvm_vcpu *vcpu)
{
return kvm_trap_emul_handle_tlb_miss(vcpu, false);
}
static int kvm_trap_emul_handle_addr_err_st(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;
int ret = RESUME_GUEST;
if (KVM_GUEST_KERNEL_MODE(vcpu)
&& (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1)) {
ret = kvm_mips_bad_store(cause, opc, run, vcpu);
} else {
kvm_err("Address Error (STORE): cause %#x, PC: %p, BadVaddr: %#lx\n",
cause, opc, badvaddr);
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
return ret;
}
static int kvm_trap_emul_handle_addr_err_ld(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;
int ret = RESUME_GUEST;
if (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1) {
ret = kvm_mips_bad_load(cause, opc, run, vcpu);
} else {
kvm_err("Address Error (LOAD): cause %#x, PC: %p, BadVaddr: %#lx\n",
cause, opc, badvaddr);
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
return ret;
}
static int kvm_trap_emul_handle_syscall(struct kvm_vcpu *vcpu)
{
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;
er = kvm_mips_emulate_syscall(cause, opc, run, vcpu);
if (er == EMULATE_DONE)
ret = RESUME_GUEST;
else {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
return ret;
}
static int kvm_trap_emul_handle_res_inst(struct kvm_vcpu *vcpu)
{
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;
er = kvm_mips_handle_ri(cause, opc, run, vcpu);
if (er == EMULATE_DONE)
ret = RESUME_GUEST;
else {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
return ret;
}
static int kvm_trap_emul_handle_break(struct kvm_vcpu *vcpu)
{
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;
er = kvm_mips_emulate_bp_exc(cause, opc, run, vcpu);
if (er == EMULATE_DONE)
ret = RESUME_GUEST;
else {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
return ret;
}
static int kvm_trap_emul_handle_trap(struct kvm_vcpu *vcpu)
{
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;
er = kvm_mips_emulate_trap_exc(cause, opc, run, vcpu);
if (er == EMULATE_DONE) {
ret = RESUME_GUEST;
} else {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
return ret;
}
static int kvm_trap_emul_handle_msa_fpe(struct kvm_vcpu *vcpu)
{
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;
er = kvm_mips_emulate_msafpe_exc(cause, opc, run, vcpu);
if (er == EMULATE_DONE) {
ret = RESUME_GUEST;
} else {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
return ret;
}
static int kvm_trap_emul_handle_fpe(struct kvm_vcpu *vcpu)
{
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;
er = kvm_mips_emulate_fpe_exc(cause, opc, run, vcpu);
if (er == EMULATE_DONE) {
ret = RESUME_GUEST;
} else {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
return ret;
}
/**
* kvm_trap_emul_handle_msa_disabled() - Guest used MSA while disabled in root.
* @vcpu: Virtual CPU context.
*
* Handle when the guest attempts to use MSA when it is disabled.
*/
static int kvm_trap_emul_handle_msa_disabled(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 (!kvm_mips_guest_has_msa(&vcpu->arch) ||
(kvm_read_c0_guest_status(cop0) & (ST0_CU1 | ST0_FR)) == ST0_CU1) {
/*
* No MSA in guest, or FPU enabled and not in FR=1 mode,
* guest reserved instruction exception
*/
er = kvm_mips_emulate_ri_exc(cause, opc, run, vcpu);
} else if (!(kvm_read_c0_guest_config5(cop0) & MIPS_CONF5_MSAEN)) {
/* MSA disabled by guest, guest MSA disabled exception */
er = kvm_mips_emulate_msadis_exc(cause, opc, run, vcpu);
} else {
/* Restore MSA/FPU state */
kvm_own_msa(vcpu);
er = EMULATE_DONE;
}
switch (er) {
case EMULATE_DONE:
ret = RESUME_GUEST;
break;
case EMULATE_FAIL:
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
break;
default:
BUG();
}
return ret;
}
static int kvm_trap_emul_vcpu_init(struct kvm_vcpu *vcpu)
{
struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
/*
* Allocate GVA -> HPA page tables.
* MIPS doesn't use the mm_struct pointer argument.
*/
kern_mm->pgd = pgd_alloc(kern_mm);
if (!kern_mm->pgd)
return -ENOMEM;
user_mm->pgd = pgd_alloc(user_mm);
if (!user_mm->pgd) {
pgd_free(kern_mm, kern_mm->pgd);
return -ENOMEM;
}
return 0;
}
static void kvm_mips_emul_free_gva_pt(pgd_t *pgd)
{
/* Don't free host kernel page tables copied from init_mm.pgd */
const unsigned long end = 0x80000000;
unsigned long pgd_va, pud_va, pmd_va;
pud_t *pud;
pmd_t *pmd;
pte_t *pte;
int i, j, k;
for (i = 0; i < USER_PTRS_PER_PGD; i++) {
if (pgd_none(pgd[i]))
continue;
pgd_va = (unsigned long)i << PGDIR_SHIFT;
if (pgd_va >= end)
break;
pud = pud_offset(pgd + i, 0);
for (j = 0; j < PTRS_PER_PUD; j++) {
if (pud_none(pud[j]))
continue;
pud_va = pgd_va | ((unsigned long)j << PUD_SHIFT);
if (pud_va >= end)
break;
pmd = pmd_offset(pud + j, 0);
for (k = 0; k < PTRS_PER_PMD; k++) {
if (pmd_none(pmd[k]))
continue;
pmd_va = pud_va | (k << PMD_SHIFT);
if (pmd_va >= end)
break;
pte = pte_offset(pmd + k, 0);
pte_free_kernel(NULL, pte);
}
pmd_free(NULL, pmd);
}
pud_free(NULL, pud);
}
pgd_free(NULL, pgd);
}
static void kvm_trap_emul_vcpu_uninit(struct kvm_vcpu *vcpu)
{
kvm_mips_emul_free_gva_pt(vcpu->arch.guest_kernel_mm.pgd);
kvm_mips_emul_free_gva_pt(vcpu->arch.guest_user_mm.pgd);
}
static int kvm_trap_emul_vcpu_setup(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
u32 config, config1;
int vcpu_id = vcpu->vcpu_id;
/*
* Arch specific stuff, set up config registers properly so that the
* guest will come up as expected
*/
#ifndef CONFIG_CPU_MIPSR6
/* r2-r5, simulate a MIPS 24kc */
kvm_write_c0_guest_prid(cop0, 0x00019300);
#else
/* r6+, simulate a generic QEMU machine */
kvm_write_c0_guest_prid(cop0, 0x00010000);
#endif
/*
* Have config1, Cacheable, noncoherent, write-back, write allocate.
* Endianness, arch revision & virtually tagged icache should match
* host.
*/
config = read_c0_config() & MIPS_CONF_AR;
config |= MIPS_CONF_M | CONF_CM_CACHABLE_NONCOHERENT | MIPS_CONF_MT_TLB;
#ifdef CONFIG_CPU_BIG_ENDIAN
config |= CONF_BE;
#endif
if (cpu_has_vtag_icache)
config |= MIPS_CONF_VI;
kvm_write_c0_guest_config(cop0, config);
/* Read the cache characteristics from the host Config1 Register */
config1 = (read_c0_config1() & ~0x7f);
/* Set up MMU size */
config1 &= ~(0x3f << 25);
config1 |= ((KVM_MIPS_GUEST_TLB_SIZE - 1) << 25);
/* We unset some bits that we aren't emulating */
config1 &= ~(MIPS_CONF1_C2 | MIPS_CONF1_MD | MIPS_CONF1_PC |
MIPS_CONF1_WR | MIPS_CONF1_CA);
kvm_write_c0_guest_config1(cop0, config1);
/* Have config3, no tertiary/secondary caches implemented */
kvm_write_c0_guest_config2(cop0, MIPS_CONF_M);
/* MIPS_CONF_M | (read_c0_config2() & 0xfff) */
/* Have config4, UserLocal */
kvm_write_c0_guest_config3(cop0, MIPS_CONF_M | MIPS_CONF3_ULRI);
/* Have config5 */
kvm_write_c0_guest_config4(cop0, MIPS_CONF_M);
/* No config6 */
kvm_write_c0_guest_config5(cop0, 0);
/* Set Wait IE/IXMT Ignore in Config7, IAR, AR */
kvm_write_c0_guest_config7(cop0, (MIPS_CONF7_WII) | (1 << 10));
/*
* Setup IntCtl defaults, compatibility mode for timer interrupts (HW5)
*/
kvm_write_c0_guest_intctl(cop0, 0xFC000000);
/* Put in vcpu id as CPUNum into Ebase Reg to handle SMP Guests */
kvm_write_c0_guest_ebase(cop0, KVM_GUEST_KSEG0 |
(vcpu_id & MIPS_EBASE_CPUNUM));
return 0;
}
static void kvm_trap_emul_flush_shadow_all(struct kvm *kvm)
{
/* Flush GVA page tables and invalidate GVA ASIDs on all VCPUs */
kvm_flush_remote_tlbs(kvm);
}
static void kvm_trap_emul_flush_shadow_memslot(struct kvm *kvm,
const struct kvm_memory_slot *slot)
{
kvm_trap_emul_flush_shadow_all(kvm);
}
static u64 kvm_trap_emul_get_one_regs[] = {
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_CP0_KSCRATCH1,
KVM_REG_MIPS_CP0_KSCRATCH2,
KVM_REG_MIPS_CP0_KSCRATCH3,
KVM_REG_MIPS_CP0_KSCRATCH4,
KVM_REG_MIPS_CP0_KSCRATCH5,
KVM_REG_MIPS_CP0_KSCRATCH6,
KVM_REG_MIPS_COUNT_CTL,
KVM_REG_MIPS_COUNT_RESUME,
KVM_REG_MIPS_COUNT_HZ,
};
static unsigned long kvm_trap_emul_num_regs(struct kvm_vcpu *vcpu)
{
return ARRAY_SIZE(kvm_trap_emul_get_one_regs);
}
static int kvm_trap_emul_copy_reg_indices(struct kvm_vcpu *vcpu,
u64 __user *indices)
{
if (copy_to_user(indices, kvm_trap_emul_get_one_regs,
sizeof(kvm_trap_emul_get_one_regs)))
return -EFAULT;
indices += ARRAY_SIZE(kvm_trap_emul_get_one_regs);
return 0;
}
static int kvm_trap_emul_get_one_reg(struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg,
s64 *v)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
switch (reg->id) {
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_COUNT:
*v = kvm_mips_read_count(vcpu);
break;
case KVM_REG_MIPS_COUNT_CTL:
*v = vcpu->arch.count_ctl;
break;
case KVM_REG_MIPS_COUNT_RESUME:
*v = ktime_to_ns(vcpu->arch.count_resume);
break;
case KVM_REG_MIPS_COUNT_HZ:
*v = vcpu->arch.count_hz;
break;
case KVM_REG_MIPS_CP0_ERROREPC:
*v = (long)kvm_read_c0_guest_errorepc(cop0);
break;
case KVM_REG_MIPS_CP0_KSCRATCH1:
*v = (long)kvm_read_c0_guest_kscratch1(cop0);
break;
case KVM_REG_MIPS_CP0_KSCRATCH2:
*v = (long)kvm_read_c0_guest_kscratch2(cop0);
break;
case KVM_REG_MIPS_CP0_KSCRATCH3:
*v = (long)kvm_read_c0_guest_kscratch3(cop0);
break;
case KVM_REG_MIPS_CP0_KSCRATCH4:
*v = (long)kvm_read_c0_guest_kscratch4(cop0);
break;
case KVM_REG_MIPS_CP0_KSCRATCH5:
*v = (long)kvm_read_c0_guest_kscratch5(cop0);
break;
case KVM_REG_MIPS_CP0_KSCRATCH6:
*v = (long)kvm_read_c0_guest_kscratch6(cop0);
break;
default:
return -EINVAL;
}
return 0;
}
static int kvm_trap_emul_set_one_reg(struct kvm_vcpu *vcpu,
const struct kvm_one_reg *reg,
s64 v)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
int ret = 0;
unsigned int cur, change;
switch (reg->id) {
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_COUNT:
kvm_mips_write_count(vcpu, v);
break;
case KVM_REG_MIPS_CP0_COMPARE:
kvm_mips_write_compare(vcpu, v, false);
break;
case KVM_REG_MIPS_CP0_CAUSE:
/*
* If the timer is stopped or started (DC bit) it must look
* atomic with changes to the interrupt pending bits (TI, IRQ5).
* A timer interrupt should not happen in between.
*/
if ((kvm_read_c0_guest_cause(cop0) ^ v) & CAUSEF_DC) {
if (v & CAUSEF_DC) {
/* disable timer first */
kvm_mips_count_disable_cause(vcpu);
kvm_change_c0_guest_cause(cop0, ~CAUSEF_DC, v);
} else {
/* enable timer last */
kvm_change_c0_guest_cause(cop0, ~CAUSEF_DC, v);
kvm_mips_count_enable_cause(vcpu);
}
} else {
kvm_write_c0_guest_cause(cop0, v);
}
break;
case KVM_REG_MIPS_CP0_CONFIG:
/* read-only for now */
break;
case KVM_REG_MIPS_CP0_CONFIG1:
cur = kvm_read_c0_guest_config1(cop0);
change = (cur ^ v) & kvm_mips_config1_wrmask(vcpu);
if (change) {
v = cur ^ change;
kvm_write_c0_guest_config1(cop0, v);
}
break;
case KVM_REG_MIPS_CP0_CONFIG2:
/* read-only for now */
break;
case KVM_REG_MIPS_CP0_CONFIG3:
cur = kvm_read_c0_guest_config3(cop0);
change = (cur ^ v) & kvm_mips_config3_wrmask(vcpu);
if (change) {
v = cur ^ change;
kvm_write_c0_guest_config3(cop0, v);
}
break;
case KVM_REG_MIPS_CP0_CONFIG4:
cur = kvm_read_c0_guest_config4(cop0);
change = (cur ^ v) & kvm_mips_config4_wrmask(vcpu);
if (change) {
v = cur ^ change;
kvm_write_c0_guest_config4(cop0, v);
}
break;
case KVM_REG_MIPS_CP0_CONFIG5:
cur = kvm_read_c0_guest_config5(cop0);
change = (cur ^ v) & kvm_mips_config5_wrmask(vcpu);
if (change) {
v = cur ^ change;
kvm_write_c0_guest_config5(cop0, v);
}
break;
case KVM_REG_MIPS_CP0_CONFIG7:
/* writes ignored */
break;
case KVM_REG_MIPS_COUNT_CTL:
ret = kvm_mips_set_count_ctl(vcpu, v);
break;
case KVM_REG_MIPS_COUNT_RESUME:
ret = kvm_mips_set_count_resume(vcpu, v);
break;
case KVM_REG_MIPS_COUNT_HZ:
ret = kvm_mips_set_count_hz(vcpu, v);
break;
case KVM_REG_MIPS_CP0_ERROREPC:
kvm_write_c0_guest_errorepc(cop0, v);
break;
case KVM_REG_MIPS_CP0_KSCRATCH1:
kvm_write_c0_guest_kscratch1(cop0, v);
break;
case KVM_REG_MIPS_CP0_KSCRATCH2:
kvm_write_c0_guest_kscratch2(cop0, v);
break;
case KVM_REG_MIPS_CP0_KSCRATCH3:
kvm_write_c0_guest_kscratch3(cop0, v);
break;
case KVM_REG_MIPS_CP0_KSCRATCH4:
kvm_write_c0_guest_kscratch4(cop0, v);
break;
case KVM_REG_MIPS_CP0_KSCRATCH5:
kvm_write_c0_guest_kscratch5(cop0, v);
break;
case KVM_REG_MIPS_CP0_KSCRATCH6:
kvm_write_c0_guest_kscratch6(cop0, v);
break;
default:
return -EINVAL;
}
return ret;
}
static int kvm_trap_emul_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
struct mm_struct *mm;
/*
* Were we in guest context? If so, restore the appropriate ASID based
* on the mode of the Guest (Kernel/User).
*/
if (current->flags & PF_VCPU) {
mm = KVM_GUEST_KERNEL_MODE(vcpu) ? kern_mm : user_mm;
if ((cpu_context(cpu, mm) ^ asid_cache(cpu)) &
asid_version_mask(cpu))
get_new_mmu_context(mm, cpu);
write_c0_entryhi(cpu_asid(cpu, mm));
TLBMISS_HANDLER_SETUP_PGD(mm->pgd);
kvm_mips_suspend_mm(cpu);
ehb();
}
return 0;
}
static int kvm_trap_emul_vcpu_put(struct kvm_vcpu *vcpu, int cpu)
{
kvm_lose_fpu(vcpu);
if (current->flags & PF_VCPU) {
/* Restore normal Linux process memory map */
if (((cpu_context(cpu, current->mm) ^ asid_cache(cpu)) &
asid_version_mask(cpu)))
get_new_mmu_context(current->mm, cpu);
write_c0_entryhi(cpu_asid(cpu, current->mm));
TLBMISS_HANDLER_SETUP_PGD(current->mm->pgd);
kvm_mips_resume_mm(cpu);
ehb();
}
return 0;
}
static void kvm_trap_emul_check_requests(struct kvm_vcpu *vcpu, int cpu,
bool reload_asid)
{
struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
struct mm_struct *mm;
int i;
if (likely(!vcpu->requests))
return;
if (kvm_check_request(KVM_REQ_TLB_FLUSH, vcpu)) {
/*
* Both kernel & user GVA mappings must be invalidated. The
* caller is just about to check whether the ASID is stale
* anyway so no need to reload it here.
*/
kvm_mips_flush_gva_pt(kern_mm->pgd, KMF_GPA | KMF_KERN);
kvm_mips_flush_gva_pt(user_mm->pgd, KMF_GPA | KMF_USER);
for_each_possible_cpu(i) {
cpu_context(i, kern_mm) = 0;
cpu_context(i, user_mm) = 0;
}
/* Generate new ASID for current mode */
if (reload_asid) {
mm = KVM_GUEST_KERNEL_MODE(vcpu) ? kern_mm : user_mm;
get_new_mmu_context(mm, cpu);
htw_stop();
write_c0_entryhi(cpu_asid(cpu, mm));
TLBMISS_HANDLER_SETUP_PGD(mm->pgd);
htw_start();
}
}
}
/**
* kvm_trap_emul_gva_lockless_begin() - Begin lockless access to GVA space.
* @vcpu: VCPU pointer.
*
* Call before a GVA space access outside of guest mode, to ensure that
* asynchronous TLB flush requests are handled or delayed until completion of
* the GVA access (as indicated by a matching kvm_trap_emul_gva_lockless_end()).
*
* Should be called with IRQs already enabled.
*/
void kvm_trap_emul_gva_lockless_begin(struct kvm_vcpu *vcpu)
{
/* We re-enable IRQs in kvm_trap_emul_gva_lockless_end() */
WARN_ON_ONCE(irqs_disabled());
/*
* The caller is about to access the GVA space, so we set the mode to
* force TLB flush requests to send an IPI, and also disable IRQs to
* delay IPI handling until kvm_trap_emul_gva_lockless_end().
*/
local_irq_disable();
/*
* Make sure the read of VCPU requests is not reordered ahead of the
* write to vcpu->mode, or we could miss a TLB flush request while
* the requester sees the VCPU as outside of guest mode and not needing
* an IPI.
*/
smp_store_mb(vcpu->mode, READING_SHADOW_PAGE_TABLES);
/*
* If a TLB flush has been requested (potentially while
* OUTSIDE_GUEST_MODE and assumed immediately effective), perform it
* before accessing the GVA space, and be sure to reload the ASID if
* necessary as it'll be immediately used.
*
* TLB flush requests after this check will trigger an IPI due to the
* mode change above, which will be delayed due to IRQs disabled.
*/
kvm_trap_emul_check_requests(vcpu, smp_processor_id(), true);
}
/**
* kvm_trap_emul_gva_lockless_end() - End lockless access to GVA space.
* @vcpu: VCPU pointer.
*
* Called after a GVA space access outside of guest mode. Should have a matching
* call to kvm_trap_emul_gva_lockless_begin().
*/
void kvm_trap_emul_gva_lockless_end(struct kvm_vcpu *vcpu)
{
/*
* Make sure the write to vcpu->mode is not reordered in front of GVA
* accesses, or a TLB flush requester may not think it necessary to send
* an IPI.
*/
smp_store_release(&vcpu->mode, OUTSIDE_GUEST_MODE);
/*
* Now that the access to GVA space is complete, its safe for pending
* TLB flush request IPIs to be handled (which indicates completion).
*/
local_irq_enable();
}
static void kvm_trap_emul_vcpu_reenter(struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mm_struct *kern_mm = &vcpu->arch.guest_kernel_mm;
struct mm_struct *user_mm = &vcpu->arch.guest_user_mm;
struct mm_struct *mm;
struct mips_coproc *cop0 = vcpu->arch.cop0;
int i, cpu = smp_processor_id();
unsigned int gasid;
/*
* No need to reload ASID, IRQs are disabled already so there's no rush,
* and we'll check if we need to regenerate below anyway before
* re-entering the guest.
*/
kvm_trap_emul_check_requests(vcpu, cpu, false);
if (KVM_GUEST_KERNEL_MODE(vcpu)) {
mm = kern_mm;
} else {
mm = user_mm;
/*
* Lazy host ASID regeneration / PT flush for guest user mode.
* If the guest ASID has changed since the last guest usermode
* execution, invalidate the stale TLB entries and flush GVA PT
* entries too.
*/
gasid = kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID;
if (gasid != vcpu->arch.last_user_gasid) {
kvm_mips_flush_gva_pt(user_mm->pgd, KMF_USER);
for_each_possible_cpu(i)
cpu_context(i, user_mm) = 0;
vcpu->arch.last_user_gasid = gasid;
}
}
/*
* Check if ASID is stale. This may happen due to a TLB flush request or
* a lazy user MM invalidation.
*/
if ((cpu_context(cpu, mm) ^ asid_cache(cpu)) &
asid_version_mask(cpu))
get_new_mmu_context(mm, cpu);
}
static int kvm_trap_emul_vcpu_run(struct kvm_run *run, struct kvm_vcpu *vcpu)
{
int cpu = smp_processor_id();
int r;
/* Check if we have any exceptions/interrupts pending */
kvm_mips_deliver_interrupts(vcpu,
kvm_read_c0_guest_cause(vcpu->arch.cop0));
kvm_trap_emul_vcpu_reenter(run, vcpu);
/*
* We use user accessors to access guest memory, but we don't want to
* invoke Linux page faulting.
*/
pagefault_disable();
/* Disable hardware page table walking while in guest */
htw_stop();
/*
* While in guest context we're in the guest's address space, not the
* host process address space, so we need to be careful not to confuse
* e.g. cache management IPIs.
*/
kvm_mips_suspend_mm(cpu);
r = vcpu->arch.vcpu_run(run, vcpu);
/* We may have migrated while handling guest exits */
cpu = smp_processor_id();
/* Restore normal Linux process memory map */
if (((cpu_context(cpu, current->mm) ^ asid_cache(cpu)) &
asid_version_mask(cpu)))
get_new_mmu_context(current->mm, cpu);
write_c0_entryhi(cpu_asid(cpu, current->mm));
TLBMISS_HANDLER_SETUP_PGD(current->mm->pgd);
kvm_mips_resume_mm(cpu);
htw_start();
pagefault_enable();
return r;
}
static struct kvm_mips_callbacks kvm_trap_emul_callbacks = {
/* exit handlers */
.handle_cop_unusable = kvm_trap_emul_handle_cop_unusable,
.handle_tlb_mod = kvm_trap_emul_handle_tlb_mod,
.handle_tlb_st_miss = kvm_trap_emul_handle_tlb_st_miss,
.handle_tlb_ld_miss = kvm_trap_emul_handle_tlb_ld_miss,
.handle_addr_err_st = kvm_trap_emul_handle_addr_err_st,
.handle_addr_err_ld = kvm_trap_emul_handle_addr_err_ld,
.handle_syscall = kvm_trap_emul_handle_syscall,
.handle_res_inst = kvm_trap_emul_handle_res_inst,
.handle_break = kvm_trap_emul_handle_break,
.handle_trap = kvm_trap_emul_handle_trap,
.handle_msa_fpe = kvm_trap_emul_handle_msa_fpe,
.handle_fpe = kvm_trap_emul_handle_fpe,
.handle_msa_disabled = kvm_trap_emul_handle_msa_disabled,
.vcpu_init = kvm_trap_emul_vcpu_init,
.vcpu_uninit = kvm_trap_emul_vcpu_uninit,
.vcpu_setup = kvm_trap_emul_vcpu_setup,
.flush_shadow_all = kvm_trap_emul_flush_shadow_all,
.flush_shadow_memslot = kvm_trap_emul_flush_shadow_memslot,
.gva_to_gpa = kvm_trap_emul_gva_to_gpa_cb,
.queue_timer_int = kvm_mips_queue_timer_int_cb,
.dequeue_timer_int = kvm_mips_dequeue_timer_int_cb,
.queue_io_int = kvm_mips_queue_io_int_cb,
.dequeue_io_int = kvm_mips_dequeue_io_int_cb,
.irq_deliver = kvm_mips_irq_deliver_cb,
.irq_clear = kvm_mips_irq_clear_cb,
.num_regs = kvm_trap_emul_num_regs,
.copy_reg_indices = kvm_trap_emul_copy_reg_indices,
.get_one_reg = kvm_trap_emul_get_one_reg,
.set_one_reg = kvm_trap_emul_set_one_reg,
.vcpu_load = kvm_trap_emul_vcpu_load,
.vcpu_put = kvm_trap_emul_vcpu_put,
.vcpu_run = kvm_trap_emul_vcpu_run,
.vcpu_reenter = kvm_trap_emul_vcpu_reenter,
};
int kvm_mips_emulation_init(struct kvm_mips_callbacks **install_callbacks)
{
*install_callbacks = &kvm_trap_emul_callbacks;
return 0;
}