KVM/MIPS32: Routines to handle specific traps/exceptions while executing the guest.

Signed-off-by: Sanjay Lal <sanjayl@kymasys.com>
Cc: kvm@vger.kernel.org
Cc: linux-mips@linux-mips.org
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
This commit is contained in:
Sanjay Lal 2012-11-21 18:34:09 -08:00 committed by Ralf Baechle
parent 06d1838db0
commit f5c236dd0a
2 changed files with 496 additions and 0 deletions

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arch/mips/kvm/kvm_cb.c Normal file
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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.
*
* Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
* Authors: Yann Le Du <ledu@kymasys.com>
*/
#include <linux/export.h>
#include <linux/kvm_host.h>
struct kvm_mips_callbacks *kvm_mips_callbacks;
EXPORT_SYMBOL(kvm_mips_callbacks);

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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: 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/module.h>
#include <linux/vmalloc.h>
#include <linux/kvm_host.h>
#include "kvm_mips_opcode.h"
#include "kvm_mips_int.h"
static gpa_t kvm_trap_emul_gva_to_gpa_cb(gva_t gva)
{
gpa_t gpa;
uint32_t kseg = KSEGX(gva);
if ((kseg == CKSEG0) || (kseg == CKSEG1))
gpa = CPHYSADDR(gva);
else {
printk("%s: cannot find GPA for GVA: %#lx\n", __func__, gva);
kvm_mips_dump_host_tlbs();
gpa = KVM_INVALID_ADDR;
}
#ifdef DEBUG
kvm_debug("%s: gva %#lx, gpa: %#llx\n", __func__, gva, gpa);
#endif
return gpa;
}
static int kvm_trap_emul_handle_cop_unusable(struct kvm_vcpu *vcpu)
{
struct kvm_run *run = vcpu->run;
uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
unsigned long cause = vcpu->arch.host_cp0_cause;
enum emulation_result er = EMULATE_DONE;
int ret = RESUME_GUEST;
if (((cause & CAUSEF_CE) >> CAUSEB_CE) == 1) {
er = kvm_mips_emulate_fpu_exc(cause, opc, run, vcpu);
} 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;
uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
unsigned long 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) {
#ifdef DEBUG
kvm_debug
("USER/KSEG23 ADDR TLB MOD fault: cause %#lx, PC: %p, BadVaddr: %#lx\n",
cause, opc, badvaddr);
#endif
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
*/
printk
("TLB MOD fault not handled, cause %#lx, 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 {
printk
("Illegal TLB Mod fault address , cause %#lx, 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_st_miss(struct kvm_vcpu *vcpu)
{
struct kvm_run *run = vcpu->run;
uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
unsigned long 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) {
#ifdef DEBUG
kvm_debug
("USER ADDR TLB LD fault: cause %#lx, PC: %p, BadVaddr: %#lx\n",
cause, opc, badvaddr);
#endif
er = kvm_mips_handle_tlbmiss(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) {
/* 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
(vcpu->arch.host_cp0_badvaddr, vcpu) < 0) {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
} else {
kvm_err
("Illegal TLB LD fault address , cause %#lx, 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_ld_miss(struct kvm_vcpu *vcpu)
{
struct kvm_run *run = vcpu->run;
uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
unsigned long 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) {
#ifdef DEBUG
kvm_debug("USER ADDR TLB ST fault: PC: %#lx, BadVaddr: %#lx\n",
vcpu->arch.pc, badvaddr);
#endif
/* 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);
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) {
if (kvm_mips_handle_kseg0_tlb_fault
(vcpu->arch.host_cp0_badvaddr, vcpu) < 0) {
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
}
} else {
printk
("Illegal TLB ST fault address , cause %#lx, 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_addr_err_st(struct kvm_vcpu *vcpu)
{
struct kvm_run *run = vcpu->run;
uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
unsigned long cause = vcpu->arch.host_cp0_cause;
enum emulation_result er = EMULATE_DONE;
int ret = RESUME_GUEST;
if (KVM_GUEST_KERNEL_MODE(vcpu)
&& (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1)) {
#ifdef DEBUG
kvm_debug("Emulate Store to MMIO space\n");
#endif
er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
if (er == EMULATE_FAIL) {
printk("Emulate Store to MMIO space failed\n");
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
} else {
run->exit_reason = KVM_EXIT_MMIO;
ret = RESUME_HOST;
}
} else {
printk
("Address Error (STORE): cause %#lx, 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;
uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
unsigned long cause = vcpu->arch.host_cp0_cause;
enum emulation_result er = EMULATE_DONE;
int ret = RESUME_GUEST;
if (KSEGX(badvaddr) == CKSEG0 || KSEGX(badvaddr) == CKSEG1) {
#ifdef DEBUG
kvm_debug("Emulate Load from MMIO space @ %#lx\n", badvaddr);
#endif
er = kvm_mips_emulate_inst(cause, opc, run, vcpu);
if (er == EMULATE_FAIL) {
printk("Emulate Load from MMIO space failed\n");
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
} else {
run->exit_reason = KVM_EXIT_MMIO;
ret = RESUME_HOST;
}
} else {
printk
("Address Error (LOAD): cause %#lx, PC: %p, BadVaddr: %#lx\n",
cause, opc, badvaddr);
run->exit_reason = KVM_EXIT_INTERNAL_ERROR;
ret = RESUME_HOST;
er = EMULATE_FAIL;
}
return ret;
}
static int kvm_trap_emul_handle_syscall(struct kvm_vcpu *vcpu)
{
struct kvm_run *run = vcpu->run;
uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
unsigned long 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;
uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
unsigned long 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;
uint32_t __user *opc = (uint32_t __user *) vcpu->arch.pc;
unsigned long 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_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
kvm_write_c0_guest_index(cop0, regs->cp0reg[MIPS_CP0_TLB_INDEX][0]);
kvm_write_c0_guest_context(cop0, regs->cp0reg[MIPS_CP0_TLB_CONTEXT][0]);
kvm_write_c0_guest_badvaddr(cop0, regs->cp0reg[MIPS_CP0_BAD_VADDR][0]);
kvm_write_c0_guest_entryhi(cop0, regs->cp0reg[MIPS_CP0_TLB_HI][0]);
kvm_write_c0_guest_epc(cop0, regs->cp0reg[MIPS_CP0_EXC_PC][0]);
kvm_write_c0_guest_status(cop0, regs->cp0reg[MIPS_CP0_STATUS][0]);
kvm_write_c0_guest_cause(cop0, regs->cp0reg[MIPS_CP0_CAUSE][0]);
kvm_write_c0_guest_pagemask(cop0,
regs->cp0reg[MIPS_CP0_TLB_PG_MASK][0]);
kvm_write_c0_guest_wired(cop0, regs->cp0reg[MIPS_CP0_TLB_WIRED][0]);
kvm_write_c0_guest_errorepc(cop0, regs->cp0reg[MIPS_CP0_ERROR_PC][0]);
return 0;
}
static int
kvm_trap_emul_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
regs->cp0reg[MIPS_CP0_TLB_INDEX][0] = kvm_read_c0_guest_index(cop0);
regs->cp0reg[MIPS_CP0_TLB_CONTEXT][0] = kvm_read_c0_guest_context(cop0);
regs->cp0reg[MIPS_CP0_BAD_VADDR][0] = kvm_read_c0_guest_badvaddr(cop0);
regs->cp0reg[MIPS_CP0_TLB_HI][0] = kvm_read_c0_guest_entryhi(cop0);
regs->cp0reg[MIPS_CP0_EXC_PC][0] = kvm_read_c0_guest_epc(cop0);
regs->cp0reg[MIPS_CP0_STATUS][0] = kvm_read_c0_guest_status(cop0);
regs->cp0reg[MIPS_CP0_CAUSE][0] = kvm_read_c0_guest_cause(cop0);
regs->cp0reg[MIPS_CP0_TLB_PG_MASK][0] =
kvm_read_c0_guest_pagemask(cop0);
regs->cp0reg[MIPS_CP0_TLB_WIRED][0] = kvm_read_c0_guest_wired(cop0);
regs->cp0reg[MIPS_CP0_ERROR_PC][0] = kvm_read_c0_guest_errorepc(cop0);
regs->cp0reg[MIPS_CP0_CONFIG][0] = kvm_read_c0_guest_config(cop0);
regs->cp0reg[MIPS_CP0_CONFIG][1] = kvm_read_c0_guest_config1(cop0);
regs->cp0reg[MIPS_CP0_CONFIG][2] = kvm_read_c0_guest_config2(cop0);
regs->cp0reg[MIPS_CP0_CONFIG][3] = kvm_read_c0_guest_config3(cop0);
regs->cp0reg[MIPS_CP0_CONFIG][7] = kvm_read_c0_guest_config7(cop0);
return 0;
}
static int kvm_trap_emul_vm_init(struct kvm *kvm)
{
return 0;
}
static int kvm_trap_emul_vcpu_init(struct kvm_vcpu *vcpu)
{
return 0;
}
static int kvm_trap_emul_vcpu_setup(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
uint32_t config1;
int vcpu_id = vcpu->vcpu_id;
/* Arch specific stuff, set up config registers properly so that the
* guest will come up as expected, for now we simulate a
* MIPS 24kc
*/
kvm_write_c0_guest_prid(cop0, 0x00019300);
kvm_write_c0_guest_config(cop0,
MIPS_CONFIG0 | (0x1 << CP0C0_AR) |
(MMU_TYPE_R4000 << CP0C0_MT));
/* 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 &=
~((1 << CP0C1_C2) | (1 << CP0C1_MD) | (1 << CP0C1_PC) |
(1 << CP0C1_WR) | (1 << CP0C1_CA));
kvm_write_c0_guest_config1(cop0, config1);
kvm_write_c0_guest_config2(cop0, MIPS_CONFIG2);
/* MIPS_CONFIG2 | (read_c0_config2() & 0xfff) */
kvm_write_c0_guest_config3(cop0,
MIPS_CONFIG3 | (0 << CP0C3_VInt) | (1 <<
CP0C3_ULRI));
/* Set Wait IE/IXMT Ignore in Config7, IAR, AR */
kvm_write_c0_guest_config7(cop0, (MIPS_CONF7_WII) | (1 << 10));
/* Setup IntCtl defaults, compatibilty 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 & 0xFF));
return 0;
}
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,
.vm_init = kvm_trap_emul_vm_init,
.vcpu_init = kvm_trap_emul_vcpu_init,
.vcpu_setup = kvm_trap_emul_vcpu_setup,
.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,
.vcpu_ioctl_get_regs = kvm_trap_emul_ioctl_get_regs,
.vcpu_ioctl_set_regs = kvm_trap_emul_ioctl_set_regs,
};
int kvm_mips_emulation_init(struct kvm_mips_callbacks **install_callbacks)
{
*install_callbacks = &kvm_trap_emul_callbacks;
return 0;
}