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linux/arch/mips/kvm/emulate.c
Linus Torvalds 7beaa24ba4 Small release overall. 
- x86: miscellaneous fixes, AVIC support (local APIC virtualization,
 AMD version)
 
 - s390: polling for interrupts after a VCPU goes to halted state is
 now enabled for s390; use hardware provided information about facility
 bits that do not need any hypervisor activity, and other fixes for
 cpu models and facilities; improve perf output; floating interrupt
 controller improvements.
 
 - MIPS: miscellaneous fixes
 
 - PPC: bugfixes only
 
 - ARM: 16K page size support, generic firmware probing layer for
 timer and GIC
 
 Christoffer Dall (KVM-ARM maintainer) says:
 "There are a few changes in this pull request touching things outside
  KVM, but they should all carry the necessary acks and it made the
  merge process much easier to do it this way."
 
 though actually the irqchip maintainers' acks didn't make it into the
 patches.  Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
 later acked at http://mid.gmane.org/573351D1.4060303@arm.com
 "more formally and for documentation purposes".
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull KVM updates from Paolo Bonzini:
 "Small release overall.

  x86:
   - miscellaneous fixes
   - AVIC support (local APIC virtualization, AMD version)

  s390:
   - polling for interrupts after a VCPU goes to halted state is now
     enabled for s390
   - use hardware provided information about facility bits that do not
     need any hypervisor activity, and other fixes for cpu models and
     facilities
   - improve perf output
   - floating interrupt controller improvements.

  MIPS:
   - miscellaneous fixes

  PPC:
   - bugfixes only

  ARM:
   - 16K page size support
   - generic firmware probing layer for timer and GIC

  Christoffer Dall (KVM-ARM maintainer) says:
    "There are a few changes in this pull request touching things
     outside KVM, but they should all carry the necessary acks and it
     made the merge process much easier to do it this way."

  though actually the irqchip maintainers' acks didn't make it into the
  patches.  Marc Zyngier, who is both irqchip and KVM-ARM maintainer,
  later acked at http://mid.gmane.org/573351D1.4060303@arm.com ('more
  formally and for documentation purposes')"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (82 commits)
  KVM: MTRR: remove MSR 0x2f8
  KVM: x86: make hwapic_isr_update and hwapic_irr_update look the same
  svm: Manage vcpu load/unload when enable AVIC
  svm: Do not intercept CR8 when enable AVIC
  svm: Do not expose x2APIC when enable AVIC
  KVM: x86: Introducing kvm_x86_ops.apicv_post_state_restore
  svm: Add VMEXIT handlers for AVIC
  svm: Add interrupt injection via AVIC
  KVM: x86: Detect and Initialize AVIC support
  svm: Introduce new AVIC VMCB registers
  KVM: split kvm_vcpu_wake_up from kvm_vcpu_kick
  KVM: x86: Introducing kvm_x86_ops VCPU blocking/unblocking hooks
  KVM: x86: Introducing kvm_x86_ops VM init/destroy hooks
  KVM: x86: Rename kvm_apic_get_reg to kvm_lapic_get_reg
  KVM: x86: Misc LAPIC changes to expose helper functions
  KVM: shrink halt polling even more for invalid wakeups
  KVM: s390: set halt polling to 80 microseconds
  KVM: halt_polling: provide a way to qualify wakeups during poll
  KVM: PPC: Book3S HV: Re-enable XICS fast path for irqfd-generated interrupts
  kvm: Conditionally register IRQ bypass consumer
  ...
2016-05-19 11:27:09 -07:00

2628 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: Instruction/Exception emulation
*
* 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/ktime.h>
#include <linux/kvm_host.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/bootmem.h>
#include <linux/random.h>
#include <asm/page.h>
#include <asm/cacheflush.h>
#include <asm/cacheops.h>
#include <asm/cpu-info.h>
#include <asm/mmu_context.h>
#include <asm/tlbflush.h>
#include <asm/inst.h>
#undef CONFIG_MIPS_MT
#include <asm/r4kcache.h>
#define CONFIG_MIPS_MT
#include "interrupt.h"
#include "commpage.h"
#include "trace.h"
/*
* Compute the return address and do emulate branch simulation, if required.
* This function should be called only in branch delay slot active.
*/
unsigned long kvm_compute_return_epc(struct kvm_vcpu *vcpu,
unsigned long instpc)
{
unsigned int dspcontrol;
union mips_instruction insn;
struct kvm_vcpu_arch *arch = &vcpu->arch;
long epc = instpc;
long nextpc = KVM_INVALID_INST;
if (epc & 3)
goto unaligned;
/* Read the instruction */
insn.word = kvm_get_inst((uint32_t *) epc, vcpu);
if (insn.word == KVM_INVALID_INST)
return KVM_INVALID_INST;
switch (insn.i_format.opcode) {
/* jr and jalr are in r_format format. */
case spec_op:
switch (insn.r_format.func) {
case jalr_op:
arch->gprs[insn.r_format.rd] = epc + 8;
/* Fall through */
case jr_op:
nextpc = arch->gprs[insn.r_format.rs];
break;
}
break;
/*
* This group contains:
* bltz_op, bgez_op, bltzl_op, bgezl_op,
* bltzal_op, bgezal_op, bltzall_op, bgezall_op.
*/
case bcond_op:
switch (insn.i_format.rt) {
case bltz_op:
case bltzl_op:
if ((long)arch->gprs[insn.i_format.rs] < 0)
epc = epc + 4 + (insn.i_format.simmediate << 2);
else
epc += 8;
nextpc = epc;
break;
case bgez_op:
case bgezl_op:
if ((long)arch->gprs[insn.i_format.rs] >= 0)
epc = epc + 4 + (insn.i_format.simmediate << 2);
else
epc += 8;
nextpc = epc;
break;
case bltzal_op:
case bltzall_op:
arch->gprs[31] = epc + 8;
if ((long)arch->gprs[insn.i_format.rs] < 0)
epc = epc + 4 + (insn.i_format.simmediate << 2);
else
epc += 8;
nextpc = epc;
break;
case bgezal_op:
case bgezall_op:
arch->gprs[31] = epc + 8;
if ((long)arch->gprs[insn.i_format.rs] >= 0)
epc = epc + 4 + (insn.i_format.simmediate << 2);
else
epc += 8;
nextpc = epc;
break;
case bposge32_op:
if (!cpu_has_dsp)
goto sigill;
dspcontrol = rddsp(0x01);
if (dspcontrol >= 32)
epc = epc + 4 + (insn.i_format.simmediate << 2);
else
epc += 8;
nextpc = epc;
break;
}
break;
/* These are unconditional and in j_format. */
case jal_op:
arch->gprs[31] = instpc + 8;
case j_op:
epc += 4;
epc >>= 28;
epc <<= 28;
epc |= (insn.j_format.target << 2);
nextpc = epc;
break;
/* These are conditional and in i_format. */
case beq_op:
case beql_op:
if (arch->gprs[insn.i_format.rs] ==
arch->gprs[insn.i_format.rt])
epc = epc + 4 + (insn.i_format.simmediate << 2);
else
epc += 8;
nextpc = epc;
break;
case bne_op:
case bnel_op:
if (arch->gprs[insn.i_format.rs] !=
arch->gprs[insn.i_format.rt])
epc = epc + 4 + (insn.i_format.simmediate << 2);
else
epc += 8;
nextpc = epc;
break;
case blez_op: /* not really i_format */
case blezl_op:
/* rt field assumed to be zero */
if ((long)arch->gprs[insn.i_format.rs] <= 0)
epc = epc + 4 + (insn.i_format.simmediate << 2);
else
epc += 8;
nextpc = epc;
break;
case bgtz_op:
case bgtzl_op:
/* rt field assumed to be zero */
if ((long)arch->gprs[insn.i_format.rs] > 0)
epc = epc + 4 + (insn.i_format.simmediate << 2);
else
epc += 8;
nextpc = epc;
break;
/* And now the FPA/cp1 branch instructions. */
case cop1_op:
kvm_err("%s: unsupported cop1_op\n", __func__);
break;
}
return nextpc;
unaligned:
kvm_err("%s: unaligned epc\n", __func__);
return nextpc;
sigill:
kvm_err("%s: DSP branch but not DSP ASE\n", __func__);
return nextpc;
}
enum emulation_result update_pc(struct kvm_vcpu *vcpu, uint32_t cause)
{
unsigned long branch_pc;
enum emulation_result er = EMULATE_DONE;
if (cause & CAUSEF_BD) {
branch_pc = kvm_compute_return_epc(vcpu, vcpu->arch.pc);
if (branch_pc == KVM_INVALID_INST) {
er = EMULATE_FAIL;
} else {
vcpu->arch.pc = branch_pc;
kvm_debug("BD update_pc(): New PC: %#lx\n",
vcpu->arch.pc);
}
} else
vcpu->arch.pc += 4;
kvm_debug("update_pc(): New PC: %#lx\n", vcpu->arch.pc);
return er;
}
/**
* kvm_mips_count_disabled() - Find whether the CP0_Count timer is disabled.
* @vcpu: Virtual CPU.
*
* Returns: 1 if the CP0_Count timer is disabled by either the guest
* CP0_Cause.DC bit or the count_ctl.DC bit.
* 0 otherwise (in which case CP0_Count timer is running).
*/
static inline int kvm_mips_count_disabled(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
return (vcpu->arch.count_ctl & KVM_REG_MIPS_COUNT_CTL_DC) ||
(kvm_read_c0_guest_cause(cop0) & CAUSEF_DC);
}
/**
* kvm_mips_ktime_to_count() - Scale ktime_t to a 32-bit count.
*
* Caches the dynamic nanosecond bias in vcpu->arch.count_dyn_bias.
*
* Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is running).
*/
static uint32_t kvm_mips_ktime_to_count(struct kvm_vcpu *vcpu, ktime_t now)
{
s64 now_ns, periods;
u64 delta;
now_ns = ktime_to_ns(now);
delta = now_ns + vcpu->arch.count_dyn_bias;
if (delta >= vcpu->arch.count_period) {
/* If delta is out of safe range the bias needs adjusting */
periods = div64_s64(now_ns, vcpu->arch.count_period);
vcpu->arch.count_dyn_bias = -periods * vcpu->arch.count_period;
/* Recalculate delta with new bias */
delta = now_ns + vcpu->arch.count_dyn_bias;
}
/*
* We've ensured that:
* delta < count_period
*
* Therefore the intermediate delta*count_hz will never overflow since
* at the boundary condition:
* delta = count_period
* delta = NSEC_PER_SEC * 2^32 / count_hz
* delta * count_hz = NSEC_PER_SEC * 2^32
*/
return div_u64(delta * vcpu->arch.count_hz, NSEC_PER_SEC);
}
/**
* kvm_mips_count_time() - Get effective current time.
* @vcpu: Virtual CPU.
*
* Get effective monotonic ktime. This is usually a straightforward ktime_get(),
* except when the master disable bit is set in count_ctl, in which case it is
* count_resume, i.e. the time that the count was disabled.
*
* Returns: Effective monotonic ktime for CP0_Count.
*/
static inline ktime_t kvm_mips_count_time(struct kvm_vcpu *vcpu)
{
if (unlikely(vcpu->arch.count_ctl & KVM_REG_MIPS_COUNT_CTL_DC))
return vcpu->arch.count_resume;
return ktime_get();
}
/**
* kvm_mips_read_count_running() - Read the current count value as if running.
* @vcpu: Virtual CPU.
* @now: Kernel time to read CP0_Count at.
*
* Returns the current guest CP0_Count register at time @now and handles if the
* timer interrupt is pending and hasn't been handled yet.
*
* Returns: The current value of the guest CP0_Count register.
*/
static uint32_t kvm_mips_read_count_running(struct kvm_vcpu *vcpu, ktime_t now)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
ktime_t expires, threshold;
uint32_t count, compare;
int running;
/* Calculate the biased and scaled guest CP0_Count */
count = vcpu->arch.count_bias + kvm_mips_ktime_to_count(vcpu, now);
compare = kvm_read_c0_guest_compare(cop0);
/*
* Find whether CP0_Count has reached the closest timer interrupt. If
* not, we shouldn't inject it.
*/
if ((int32_t)(count - compare) < 0)
return count;
/*
* The CP0_Count we're going to return has already reached the closest
* timer interrupt. Quickly check if it really is a new interrupt by
* looking at whether the interval until the hrtimer expiry time is
* less than 1/4 of the timer period.
*/
expires = hrtimer_get_expires(&vcpu->arch.comparecount_timer);
threshold = ktime_add_ns(now, vcpu->arch.count_period / 4);
if (ktime_before(expires, threshold)) {
/*
* Cancel it while we handle it so there's no chance of
* interference with the timeout handler.
*/
running = hrtimer_cancel(&vcpu->arch.comparecount_timer);
/* Nothing should be waiting on the timeout */
kvm_mips_callbacks->queue_timer_int(vcpu);
/*
* Restart the timer if it was running based on the expiry time
* we read, so that we don't push it back 2 periods.
*/
if (running) {
expires = ktime_add_ns(expires,
vcpu->arch.count_period);
hrtimer_start(&vcpu->arch.comparecount_timer, expires,
HRTIMER_MODE_ABS);
}
}
return count;
}
/**
* kvm_mips_read_count() - Read the current count value.
* @vcpu: Virtual CPU.
*
* Read the current guest CP0_Count value, taking into account whether the timer
* is stopped.
*
* Returns: The current guest CP0_Count value.
*/
uint32_t kvm_mips_read_count(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
/* If count disabled just read static copy of count */
if (kvm_mips_count_disabled(vcpu))
return kvm_read_c0_guest_count(cop0);
return kvm_mips_read_count_running(vcpu, ktime_get());
}
/**
* kvm_mips_freeze_hrtimer() - Safely stop the hrtimer.
* @vcpu: Virtual CPU.
* @count: Output pointer for CP0_Count value at point of freeze.
*
* Freeze the hrtimer safely and return both the ktime and the CP0_Count value
* at the point it was frozen. It is guaranteed that any pending interrupts at
* the point it was frozen are handled, and none after that point.
*
* This is useful where the time/CP0_Count is needed in the calculation of the
* new parameters.
*
* Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is running).
*
* Returns: The ktime at the point of freeze.
*/
static ktime_t kvm_mips_freeze_hrtimer(struct kvm_vcpu *vcpu,
uint32_t *count)
{
ktime_t now;
/* stop hrtimer before finding time */
hrtimer_cancel(&vcpu->arch.comparecount_timer);
now = ktime_get();
/* find count at this point and handle pending hrtimer */
*count = kvm_mips_read_count_running(vcpu, now);
return now;
}
/**
* kvm_mips_resume_hrtimer() - Resume hrtimer, updating expiry.
* @vcpu: Virtual CPU.
* @now: ktime at point of resume.
* @count: CP0_Count at point of resume.
*
* Resumes the timer and updates the timer expiry based on @now and @count.
* This can be used in conjunction with kvm_mips_freeze_timer() when timer
* parameters need to be changed.
*
* It is guaranteed that a timer interrupt immediately after resume will be
* handled, but not if CP_Compare is exactly at @count. That case is already
* handled by kvm_mips_freeze_timer().
*
* Assumes !kvm_mips_count_disabled(@vcpu) (guest CP0_Count timer is running).
*/
static void kvm_mips_resume_hrtimer(struct kvm_vcpu *vcpu,
ktime_t now, uint32_t count)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
uint32_t compare;
u64 delta;
ktime_t expire;
/* Calculate timeout (wrap 0 to 2^32) */
compare = kvm_read_c0_guest_compare(cop0);
delta = (u64)(uint32_t)(compare - count - 1) + 1;
delta = div_u64(delta * NSEC_PER_SEC, vcpu->arch.count_hz);
expire = ktime_add_ns(now, delta);
/* Update hrtimer to use new timeout */
hrtimer_cancel(&vcpu->arch.comparecount_timer);
hrtimer_start(&vcpu->arch.comparecount_timer, expire, HRTIMER_MODE_ABS);
}
/**
* kvm_mips_write_count() - Modify the count and update timer.
* @vcpu: Virtual CPU.
* @count: Guest CP0_Count value to set.
*
* Sets the CP0_Count value and updates the timer accordingly.
*/
void kvm_mips_write_count(struct kvm_vcpu *vcpu, uint32_t count)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
ktime_t now;
/* Calculate bias */
now = kvm_mips_count_time(vcpu);
vcpu->arch.count_bias = count - kvm_mips_ktime_to_count(vcpu, now);
if (kvm_mips_count_disabled(vcpu))
/* The timer's disabled, adjust the static count */
kvm_write_c0_guest_count(cop0, count);
else
/* Update timeout */
kvm_mips_resume_hrtimer(vcpu, now, count);
}
/**
* kvm_mips_init_count() - Initialise timer.
* @vcpu: Virtual CPU.
*
* Initialise the timer to a sensible frequency, namely 100MHz, zero it, and set
* it going if it's enabled.
*/
void kvm_mips_init_count(struct kvm_vcpu *vcpu)
{
/* 100 MHz */
vcpu->arch.count_hz = 100*1000*1000;
vcpu->arch.count_period = div_u64((u64)NSEC_PER_SEC << 32,
vcpu->arch.count_hz);
vcpu->arch.count_dyn_bias = 0;
/* Starting at 0 */
kvm_mips_write_count(vcpu, 0);
}
/**
* kvm_mips_set_count_hz() - Update the frequency of the timer.
* @vcpu: Virtual CPU.
* @count_hz: Frequency of CP0_Count timer in Hz.
*
* Change the frequency of the CP0_Count timer. This is done atomically so that
* CP0_Count is continuous and no timer interrupt is lost.
*
* Returns: -EINVAL if @count_hz is out of range.
* 0 on success.
*/
int kvm_mips_set_count_hz(struct kvm_vcpu *vcpu, s64 count_hz)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
int dc;
ktime_t now;
u32 count;
/* ensure the frequency is in a sensible range... */
if (count_hz <= 0 || count_hz > NSEC_PER_SEC)
return -EINVAL;
/* ... and has actually changed */
if (vcpu->arch.count_hz == count_hz)
return 0;
/* Safely freeze timer so we can keep it continuous */
dc = kvm_mips_count_disabled(vcpu);
if (dc) {
now = kvm_mips_count_time(vcpu);
count = kvm_read_c0_guest_count(cop0);
} else {
now = kvm_mips_freeze_hrtimer(vcpu, &count);
}
/* Update the frequency */
vcpu->arch.count_hz = count_hz;
vcpu->arch.count_period = div_u64((u64)NSEC_PER_SEC << 32, count_hz);
vcpu->arch.count_dyn_bias = 0;
/* Calculate adjusted bias so dynamic count is unchanged */
vcpu->arch.count_bias = count - kvm_mips_ktime_to_count(vcpu, now);
/* Update and resume hrtimer */
if (!dc)
kvm_mips_resume_hrtimer(vcpu, now, count);
return 0;
}
/**
* kvm_mips_write_compare() - Modify compare and update timer.
* @vcpu: Virtual CPU.
* @compare: New CP0_Compare value.
* @ack: Whether to acknowledge timer interrupt.
*
* Update CP0_Compare to a new value and update the timeout.
* If @ack, atomically acknowledge any pending timer interrupt, otherwise ensure
* any pending timer interrupt is preserved.
*/
void kvm_mips_write_compare(struct kvm_vcpu *vcpu, uint32_t compare, bool ack)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
int dc;
u32 old_compare = kvm_read_c0_guest_compare(cop0);
ktime_t now;
uint32_t count;
/* if unchanged, must just be an ack */
if (old_compare == compare) {
if (!ack)
return;
kvm_mips_callbacks->dequeue_timer_int(vcpu);
kvm_write_c0_guest_compare(cop0, compare);
return;
}
/* freeze_hrtimer() takes care of timer interrupts <= count */
dc = kvm_mips_count_disabled(vcpu);
if (!dc)
now = kvm_mips_freeze_hrtimer(vcpu, &count);
if (ack)
kvm_mips_callbacks->dequeue_timer_int(vcpu);
kvm_write_c0_guest_compare(cop0, compare);
/* resume_hrtimer() takes care of timer interrupts > count */
if (!dc)
kvm_mips_resume_hrtimer(vcpu, now, count);
}
/**
* kvm_mips_count_disable() - Disable count.
* @vcpu: Virtual CPU.
*
* Disable the CP0_Count timer. A timer interrupt on or before the final stop
* time will be handled but not after.
*
* Assumes CP0_Count was previously enabled but now Guest.CP0_Cause.DC or
* count_ctl.DC has been set (count disabled).
*
* Returns: The time that the timer was stopped.
*/
static ktime_t kvm_mips_count_disable(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
uint32_t count;
ktime_t now;
/* Stop hrtimer */
hrtimer_cancel(&vcpu->arch.comparecount_timer);
/* Set the static count from the dynamic count, handling pending TI */
now = ktime_get();
count = kvm_mips_read_count_running(vcpu, now);
kvm_write_c0_guest_count(cop0, count);
return now;
}
/**
* kvm_mips_count_disable_cause() - Disable count using CP0_Cause.DC.
* @vcpu: Virtual CPU.
*
* Disable the CP0_Count timer and set CP0_Cause.DC. A timer interrupt on or
* before the final stop time will be handled if the timer isn't disabled by
* count_ctl.DC, but not after.
*
* Assumes CP0_Cause.DC is clear (count enabled).
*/
void kvm_mips_count_disable_cause(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
kvm_set_c0_guest_cause(cop0, CAUSEF_DC);
if (!(vcpu->arch.count_ctl & KVM_REG_MIPS_COUNT_CTL_DC))
kvm_mips_count_disable(vcpu);
}
/**
* kvm_mips_count_enable_cause() - Enable count using CP0_Cause.DC.
* @vcpu: Virtual CPU.
*
* Enable the CP0_Count timer and clear CP0_Cause.DC. A timer interrupt after
* the start time will be handled if the timer isn't disabled by count_ctl.DC,
* potentially before even returning, so the caller should be careful with
* ordering of CP0_Cause modifications so as not to lose it.
*
* Assumes CP0_Cause.DC is set (count disabled).
*/
void kvm_mips_count_enable_cause(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
uint32_t count;
kvm_clear_c0_guest_cause(cop0, CAUSEF_DC);
/*
* Set the dynamic count to match the static count.
* This starts the hrtimer if count_ctl.DC allows it.
* Otherwise it conveniently updates the biases.
*/
count = kvm_read_c0_guest_count(cop0);
kvm_mips_write_count(vcpu, count);
}
/**
* kvm_mips_set_count_ctl() - Update the count control KVM register.
* @vcpu: Virtual CPU.
* @count_ctl: Count control register new value.
*
* Set the count control KVM register. The timer is updated accordingly.
*
* Returns: -EINVAL if reserved bits are set.
* 0 on success.
*/
int kvm_mips_set_count_ctl(struct kvm_vcpu *vcpu, s64 count_ctl)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
s64 changed = count_ctl ^ vcpu->arch.count_ctl;
s64 delta;
ktime_t expire, now;
uint32_t count, compare;
/* Only allow defined bits to be changed */
if (changed & ~(s64)(KVM_REG_MIPS_COUNT_CTL_DC))
return -EINVAL;
/* Apply new value */
vcpu->arch.count_ctl = count_ctl;
/* Master CP0_Count disable */
if (changed & KVM_REG_MIPS_COUNT_CTL_DC) {
/* Is CP0_Cause.DC already disabling CP0_Count? */
if (kvm_read_c0_guest_cause(cop0) & CAUSEF_DC) {
if (count_ctl & KVM_REG_MIPS_COUNT_CTL_DC)
/* Just record the current time */
vcpu->arch.count_resume = ktime_get();
} else if (count_ctl & KVM_REG_MIPS_COUNT_CTL_DC) {
/* disable timer and record current time */
vcpu->arch.count_resume = kvm_mips_count_disable(vcpu);
} else {
/*
* Calculate timeout relative to static count at resume
* time (wrap 0 to 2^32).
*/
count = kvm_read_c0_guest_count(cop0);
compare = kvm_read_c0_guest_compare(cop0);
delta = (u64)(uint32_t)(compare - count - 1) + 1;
delta = div_u64(delta * NSEC_PER_SEC,
vcpu->arch.count_hz);
expire = ktime_add_ns(vcpu->arch.count_resume, delta);
/* Handle pending interrupt */
now = ktime_get();
if (ktime_compare(now, expire) >= 0)
/* Nothing should be waiting on the timeout */
kvm_mips_callbacks->queue_timer_int(vcpu);
/* Resume hrtimer without changing bias */
count = kvm_mips_read_count_running(vcpu, now);
kvm_mips_resume_hrtimer(vcpu, now, count);
}
}
return 0;
}
/**
* kvm_mips_set_count_resume() - Update the count resume KVM register.
* @vcpu: Virtual CPU.
* @count_resume: Count resume register new value.
*
* Set the count resume KVM register.
*
* Returns: -EINVAL if out of valid range (0..now).
* 0 on success.
*/
int kvm_mips_set_count_resume(struct kvm_vcpu *vcpu, s64 count_resume)
{
/*
* It doesn't make sense for the resume time to be in the future, as it
* would be possible for the next interrupt to be more than a full
* period in the future.
*/
if (count_resume < 0 || count_resume > ktime_to_ns(ktime_get()))
return -EINVAL;
vcpu->arch.count_resume = ns_to_ktime(count_resume);
return 0;
}
/**
* kvm_mips_count_timeout() - Push timer forward on timeout.
* @vcpu: Virtual CPU.
*
* Handle an hrtimer event by push the hrtimer forward a period.
*
* Returns: The hrtimer_restart value to return to the hrtimer subsystem.
*/
enum hrtimer_restart kvm_mips_count_timeout(struct kvm_vcpu *vcpu)
{
/* Add the Count period to the current expiry time */
hrtimer_add_expires_ns(&vcpu->arch.comparecount_timer,
vcpu->arch.count_period);
return HRTIMER_RESTART;
}
enum emulation_result kvm_mips_emul_eret(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
enum emulation_result er = EMULATE_DONE;
if (kvm_read_c0_guest_status(cop0) & ST0_EXL) {
kvm_debug("[%#lx] ERET to %#lx\n", vcpu->arch.pc,
kvm_read_c0_guest_epc(cop0));
kvm_clear_c0_guest_status(cop0, ST0_EXL);
vcpu->arch.pc = kvm_read_c0_guest_epc(cop0);
} else if (kvm_read_c0_guest_status(cop0) & ST0_ERL) {
kvm_clear_c0_guest_status(cop0, ST0_ERL);
vcpu->arch.pc = kvm_read_c0_guest_errorepc(cop0);
} else {
kvm_err("[%#lx] ERET when MIPS_SR_EXL|MIPS_SR_ERL == 0\n",
vcpu->arch.pc);
er = EMULATE_FAIL;
}
return er;
}
enum emulation_result kvm_mips_emul_wait(struct kvm_vcpu *vcpu)
{
kvm_debug("[%#lx] !!!WAIT!!! (%#lx)\n", vcpu->arch.pc,
vcpu->arch.pending_exceptions);
++vcpu->stat.wait_exits;
trace_kvm_exit(vcpu, WAIT_EXITS);
if (!vcpu->arch.pending_exceptions) {
vcpu->arch.wait = 1;
kvm_vcpu_block(vcpu);
/*
* We we are runnable, then definitely go off to user space to
* check if any I/O interrupts are pending.
*/
if (kvm_check_request(KVM_REQ_UNHALT, vcpu)) {
clear_bit(KVM_REQ_UNHALT, &vcpu->requests);
vcpu->run->exit_reason = KVM_EXIT_IRQ_WINDOW_OPEN;
}
}
return EMULATE_DONE;
}
/*
* XXXKYMA: Linux doesn't seem to use TLBR, return EMULATE_FAIL for now so that
* we can catch this, if things ever change
*/
enum emulation_result kvm_mips_emul_tlbr(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
uint32_t pc = vcpu->arch.pc;
kvm_err("[%#x] COP0_TLBR [%ld]\n", pc, kvm_read_c0_guest_index(cop0));
return EMULATE_FAIL;
}
/* Write Guest TLB Entry @ Index */
enum emulation_result kvm_mips_emul_tlbwi(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
int index = kvm_read_c0_guest_index(cop0);
struct kvm_mips_tlb *tlb = NULL;
uint32_t pc = vcpu->arch.pc;
if (index < 0 || index >= KVM_MIPS_GUEST_TLB_SIZE) {
kvm_debug("%s: illegal index: %d\n", __func__, index);
kvm_debug("[%#x] COP0_TLBWI [%d] (entryhi: %#lx, entrylo0: %#lx entrylo1: %#lx, mask: %#lx)\n",
pc, index, kvm_read_c0_guest_entryhi(cop0),
kvm_read_c0_guest_entrylo0(cop0),
kvm_read_c0_guest_entrylo1(cop0),
kvm_read_c0_guest_pagemask(cop0));
index = (index & ~0x80000000) % KVM_MIPS_GUEST_TLB_SIZE;
}
tlb = &vcpu->arch.guest_tlb[index];
/*
* Probe the shadow host TLB for the entry being overwritten, if one
* matches, invalidate it
*/
kvm_mips_host_tlb_inv(vcpu, tlb->tlb_hi);
tlb->tlb_mask = kvm_read_c0_guest_pagemask(cop0);
tlb->tlb_hi = kvm_read_c0_guest_entryhi(cop0);
tlb->tlb_lo0 = kvm_read_c0_guest_entrylo0(cop0);
tlb->tlb_lo1 = kvm_read_c0_guest_entrylo1(cop0);
kvm_debug("[%#x] COP0_TLBWI [%d] (entryhi: %#lx, entrylo0: %#lx entrylo1: %#lx, mask: %#lx)\n",
pc, index, kvm_read_c0_guest_entryhi(cop0),
kvm_read_c0_guest_entrylo0(cop0),
kvm_read_c0_guest_entrylo1(cop0),
kvm_read_c0_guest_pagemask(cop0));
return EMULATE_DONE;
}
/* Write Guest TLB Entry @ Random Index */
enum emulation_result kvm_mips_emul_tlbwr(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_mips_tlb *tlb = NULL;
uint32_t pc = vcpu->arch.pc;
int index;
get_random_bytes(&index, sizeof(index));
index &= (KVM_MIPS_GUEST_TLB_SIZE - 1);
tlb = &vcpu->arch.guest_tlb[index];
/*
* Probe the shadow host TLB for the entry being overwritten, if one
* matches, invalidate it
*/
kvm_mips_host_tlb_inv(vcpu, tlb->tlb_hi);
tlb->tlb_mask = kvm_read_c0_guest_pagemask(cop0);
tlb->tlb_hi = kvm_read_c0_guest_entryhi(cop0);
tlb->tlb_lo0 = kvm_read_c0_guest_entrylo0(cop0);
tlb->tlb_lo1 = kvm_read_c0_guest_entrylo1(cop0);
kvm_debug("[%#x] COP0_TLBWR[%d] (entryhi: %#lx, entrylo0: %#lx entrylo1: %#lx)\n",
pc, index, kvm_read_c0_guest_entryhi(cop0),
kvm_read_c0_guest_entrylo0(cop0),
kvm_read_c0_guest_entrylo1(cop0));
return EMULATE_DONE;
}
enum emulation_result kvm_mips_emul_tlbp(struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
long entryhi = kvm_read_c0_guest_entryhi(cop0);
uint32_t pc = vcpu->arch.pc;
int index = -1;
index = kvm_mips_guest_tlb_lookup(vcpu, entryhi);
kvm_write_c0_guest_index(cop0, index);
kvm_debug("[%#x] COP0_TLBP (entryhi: %#lx), index: %d\n", pc, entryhi,
index);
return EMULATE_DONE;
}
/**
* kvm_mips_config1_wrmask() - Find mask of writable bits in guest Config1
* @vcpu: Virtual CPU.
*
* Finds the mask of bits which are writable in the guest's Config1 CP0
* register, by userland (currently read-only to the guest).
*/
unsigned int kvm_mips_config1_wrmask(struct kvm_vcpu *vcpu)
{
unsigned int mask = 0;
/* Permit FPU to be present if FPU is supported */
if (kvm_mips_guest_can_have_fpu(&vcpu->arch))
mask |= MIPS_CONF1_FP;
return mask;
}
/**
* kvm_mips_config3_wrmask() - Find mask of writable bits in guest Config3
* @vcpu: Virtual CPU.
*
* Finds the mask of bits which are writable in the guest's Config3 CP0
* register, by userland (currently read-only to the guest).
*/
unsigned int kvm_mips_config3_wrmask(struct kvm_vcpu *vcpu)
{
/* Config4 is optional */
unsigned int mask = MIPS_CONF_M;
/* Permit MSA to be present if MSA is supported */
if (kvm_mips_guest_can_have_msa(&vcpu->arch))
mask |= MIPS_CONF3_MSA;
return mask;
}
/**
* kvm_mips_config4_wrmask() - Find mask of writable bits in guest Config4
* @vcpu: Virtual CPU.
*
* Finds the mask of bits which are writable in the guest's Config4 CP0
* register, by userland (currently read-only to the guest).
*/
unsigned int kvm_mips_config4_wrmask(struct kvm_vcpu *vcpu)
{
/* Config5 is optional */
return MIPS_CONF_M;
}
/**
* kvm_mips_config5_wrmask() - Find mask of writable bits in guest Config5
* @vcpu: Virtual CPU.
*
* Finds the mask of bits which are writable in the guest's Config5 CP0
* register, by the guest itself.
*/
unsigned int kvm_mips_config5_wrmask(struct kvm_vcpu *vcpu)
{
unsigned int mask = 0;
/* Permit MSAEn changes if MSA supported and enabled */
if (kvm_mips_guest_has_msa(&vcpu->arch))
mask |= MIPS_CONF5_MSAEN;
/*
* Permit guest FPU mode changes if FPU is enabled and the relevant
* feature exists according to FIR register.
*/
if (kvm_mips_guest_has_fpu(&vcpu->arch)) {
if (cpu_has_fre)
mask |= MIPS_CONF5_FRE;
/* We don't support UFR or UFE */
}
return mask;
}
enum emulation_result kvm_mips_emulate_CP0(uint32_t inst, uint32_t *opc,
uint32_t cause, struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
enum emulation_result er = EMULATE_DONE;
int32_t rt, rd, copz, sel, co_bit, op;
uint32_t pc = vcpu->arch.pc;
unsigned long curr_pc;
/*
* Update PC and hold onto current PC in case there is
* an error and we want to rollback the PC
*/
curr_pc = vcpu->arch.pc;
er = update_pc(vcpu, cause);
if (er == EMULATE_FAIL)
return er;
copz = (inst >> 21) & 0x1f;
rt = (inst >> 16) & 0x1f;
rd = (inst >> 11) & 0x1f;
sel = inst & 0x7;
co_bit = (inst >> 25) & 1;
if (co_bit) {
op = (inst) & 0xff;
switch (op) {
case tlbr_op: /* Read indexed TLB entry */
er = kvm_mips_emul_tlbr(vcpu);
break;
case tlbwi_op: /* Write indexed */
er = kvm_mips_emul_tlbwi(vcpu);
break;
case tlbwr_op: /* Write random */
er = kvm_mips_emul_tlbwr(vcpu);
break;
case tlbp_op: /* TLB Probe */
er = kvm_mips_emul_tlbp(vcpu);
break;
case rfe_op:
kvm_err("!!!COP0_RFE!!!\n");
break;
case eret_op:
er = kvm_mips_emul_eret(vcpu);
goto dont_update_pc;
break;
case wait_op:
er = kvm_mips_emul_wait(vcpu);
break;
}
} else {
switch (copz) {
case mfc_op:
#ifdef CONFIG_KVM_MIPS_DEBUG_COP0_COUNTERS
cop0->stat[rd][sel]++;
#endif
/* Get reg */
if ((rd == MIPS_CP0_COUNT) && (sel == 0)) {
vcpu->arch.gprs[rt] = kvm_mips_read_count(vcpu);
} else if ((rd == MIPS_CP0_ERRCTL) && (sel == 0)) {
vcpu->arch.gprs[rt] = 0x0;
#ifdef CONFIG_KVM_MIPS_DYN_TRANS
kvm_mips_trans_mfc0(inst, opc, vcpu);
#endif
} else {
vcpu->arch.gprs[rt] = cop0->reg[rd][sel];
#ifdef CONFIG_KVM_MIPS_DYN_TRANS
kvm_mips_trans_mfc0(inst, opc, vcpu);
#endif
}
kvm_debug
("[%#x] MFCz[%d][%d], vcpu->arch.gprs[%d]: %#lx\n",
pc, rd, sel, rt, vcpu->arch.gprs[rt]);
break;
case dmfc_op:
vcpu->arch.gprs[rt] = cop0->reg[rd][sel];
break;
case mtc_op:
#ifdef CONFIG_KVM_MIPS_DEBUG_COP0_COUNTERS
cop0->stat[rd][sel]++;
#endif
if ((rd == MIPS_CP0_TLB_INDEX)
&& (vcpu->arch.gprs[rt] >=
KVM_MIPS_GUEST_TLB_SIZE)) {
kvm_err("Invalid TLB Index: %ld",
vcpu->arch.gprs[rt]);
er = EMULATE_FAIL;
break;
}
#define C0_EBASE_CORE_MASK 0xff
if ((rd == MIPS_CP0_PRID) && (sel == 1)) {
/* Preserve CORE number */
kvm_change_c0_guest_ebase(cop0,
~(C0_EBASE_CORE_MASK),
vcpu->arch.gprs[rt]);
kvm_err("MTCz, cop0->reg[EBASE]: %#lx\n",
kvm_read_c0_guest_ebase(cop0));
} else if (rd == MIPS_CP0_TLB_HI && sel == 0) {
uint32_t nasid =
vcpu->arch.gprs[rt] & KVM_ENTRYHI_ASID;
if ((KSEGX(vcpu->arch.gprs[rt]) != CKSEG0) &&
((kvm_read_c0_guest_entryhi(cop0) &
KVM_ENTRYHI_ASID) != nasid)) {
kvm_debug("MTCz, change ASID from %#lx to %#lx\n",
kvm_read_c0_guest_entryhi(cop0)
& KVM_ENTRYHI_ASID,
vcpu->arch.gprs[rt]
& KVM_ENTRYHI_ASID);
/* Blow away the shadow host TLBs */
kvm_mips_flush_host_tlb(1);
}
kvm_write_c0_guest_entryhi(cop0,
vcpu->arch.gprs[rt]);
}
/* Are we writing to COUNT */
else if ((rd == MIPS_CP0_COUNT) && (sel == 0)) {
kvm_mips_write_count(vcpu, vcpu->arch.gprs[rt]);
goto done;
} else if ((rd == MIPS_CP0_COMPARE) && (sel == 0)) {
kvm_debug("[%#x] MTCz, COMPARE %#lx <- %#lx\n",
pc, kvm_read_c0_guest_compare(cop0),
vcpu->arch.gprs[rt]);
/* If we are writing to COMPARE */
/* Clear pending timer interrupt, if any */
kvm_mips_write_compare(vcpu,
vcpu->arch.gprs[rt],
true);
} else if ((rd == MIPS_CP0_STATUS) && (sel == 0)) {
unsigned int old_val, val, change;
old_val = kvm_read_c0_guest_status(cop0);
val = vcpu->arch.gprs[rt];
change = val ^ old_val;
/* Make sure that the NMI bit is never set */
val &= ~ST0_NMI;
/*
* Don't allow CU1 or FR to be set unless FPU
* capability enabled and exists in guest
* configuration.
*/
if (!kvm_mips_guest_has_fpu(&vcpu->arch))
val &= ~(ST0_CU1 | ST0_FR);
/*
* Also don't allow FR to be set if host doesn't
* support it.
*/
if (!(current_cpu_data.fpu_id & MIPS_FPIR_F64))
val &= ~ST0_FR;
/* Handle changes in FPU mode */
preempt_disable();
/*
* FPU and Vector register state is made
* UNPREDICTABLE by a change of FR, so don't
* even bother saving it.
*/
if (change & ST0_FR)
kvm_drop_fpu(vcpu);
/*
* 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.
*/
if (change & ST0_CU1 && !(val & ST0_FR) &&
vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA)
kvm_lose_fpu(vcpu);
/*
* Propagate CU1 (FPU enable) changes
* immediately if the FPU context is already
* loaded. When disabling we leave the context
* loaded so it can be quickly enabled again in
* the near future.
*/
if (change & ST0_CU1 &&
vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU)
change_c0_status(ST0_CU1, val);
preempt_enable();
kvm_write_c0_guest_status(cop0, val);
#ifdef CONFIG_KVM_MIPS_DYN_TRANS
/*
* If FPU present, we need CU1/FR bits to take
* effect fairly soon.
*/
if (!kvm_mips_guest_has_fpu(&vcpu->arch))
kvm_mips_trans_mtc0(inst, opc, vcpu);
#endif
} else if ((rd == MIPS_CP0_CONFIG) && (sel == 5)) {
unsigned int old_val, val, change, wrmask;
old_val = kvm_read_c0_guest_config5(cop0);
val = vcpu->arch.gprs[rt];
/* Only a few bits are writable in Config5 */
wrmask = kvm_mips_config5_wrmask(vcpu);
change = (val ^ old_val) & wrmask;
val = old_val ^ change;
/* Handle changes in FPU/MSA modes */
preempt_disable();
/*
* Propagate FRE changes immediately if the FPU
* context is already loaded.
*/
if (change & MIPS_CONF5_FRE &&
vcpu->arch.fpu_inuse & KVM_MIPS_FPU_FPU)
change_c0_config5(MIPS_CONF5_FRE, val);
/*
* Propagate MSAEn changes immediately if the
* MSA context is already loaded. When disabling
* we leave the context loaded so it can be
* quickly enabled again in the near future.
*/
if (change & MIPS_CONF5_MSAEN &&
vcpu->arch.fpu_inuse & KVM_MIPS_FPU_MSA)
change_c0_config5(MIPS_CONF5_MSAEN,
val);
preempt_enable();
kvm_write_c0_guest_config5(cop0, val);
} else if ((rd == MIPS_CP0_CAUSE) && (sel == 0)) {
uint32_t old_cause, new_cause;
old_cause = kvm_read_c0_guest_cause(cop0);
new_cause = vcpu->arch.gprs[rt];
/* Update R/W bits */
kvm_change_c0_guest_cause(cop0, 0x08800300,
new_cause);
/* DC bit enabling/disabling timer? */
if ((old_cause ^ new_cause) & CAUSEF_DC) {
if (new_cause & CAUSEF_DC)
kvm_mips_count_disable_cause(vcpu);
else
kvm_mips_count_enable_cause(vcpu);
}
} else {
cop0->reg[rd][sel] = vcpu->arch.gprs[rt];
#ifdef CONFIG_KVM_MIPS_DYN_TRANS
kvm_mips_trans_mtc0(inst, opc, vcpu);
#endif
}
kvm_debug("[%#x] MTCz, cop0->reg[%d][%d]: %#lx\n", pc,
rd, sel, cop0->reg[rd][sel]);
break;
case dmtc_op:
kvm_err("!!!!!!![%#lx]dmtc_op: rt: %d, rd: %d, sel: %d!!!!!!\n",
vcpu->arch.pc, rt, rd, sel);
er = EMULATE_FAIL;
break;
case mfmc0_op:
#ifdef KVM_MIPS_DEBUG_COP0_COUNTERS
cop0->stat[MIPS_CP0_STATUS][0]++;
#endif
if (rt != 0)
vcpu->arch.gprs[rt] =
kvm_read_c0_guest_status(cop0);
/* EI */
if (inst & 0x20) {
kvm_debug("[%#lx] mfmc0_op: EI\n",
vcpu->arch.pc);
kvm_set_c0_guest_status(cop0, ST0_IE);
} else {
kvm_debug("[%#lx] mfmc0_op: DI\n",
vcpu->arch.pc);
kvm_clear_c0_guest_status(cop0, ST0_IE);
}
break;
case wrpgpr_op:
{
uint32_t css =
cop0->reg[MIPS_CP0_STATUS][2] & 0xf;
uint32_t pss =
(cop0->reg[MIPS_CP0_STATUS][2] >> 6) & 0xf;
/*
* We don't support any shadow register sets, so
* SRSCtl[PSS] == SRSCtl[CSS] = 0
*/
if (css || pss) {
er = EMULATE_FAIL;
break;
}
kvm_debug("WRPGPR[%d][%d] = %#lx\n", pss, rd,
vcpu->arch.gprs[rt]);
vcpu->arch.gprs[rd] = vcpu->arch.gprs[rt];
}
break;
default:
kvm_err("[%#lx]MachEmulateCP0: unsupported COP0, copz: 0x%x\n",
vcpu->arch.pc, copz);
er = EMULATE_FAIL;
break;
}
}
done:
/* Rollback PC only if emulation was unsuccessful */
if (er == EMULATE_FAIL)
vcpu->arch.pc = curr_pc;
dont_update_pc:
/*
* This is for special instructions whose emulation
* updates the PC, so do not overwrite the PC under
* any circumstances
*/
return er;
}
enum emulation_result kvm_mips_emulate_store(uint32_t inst, uint32_t cause,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
enum emulation_result er = EMULATE_DO_MMIO;
int32_t op, base, rt, offset;
uint32_t bytes;
void *data = run->mmio.data;
unsigned long curr_pc;
/*
* Update PC and hold onto current PC in case there is
* an error and we want to rollback the PC
*/
curr_pc = vcpu->arch.pc;
er = update_pc(vcpu, cause);
if (er == EMULATE_FAIL)
return er;
rt = (inst >> 16) & 0x1f;
base = (inst >> 21) & 0x1f;
offset = inst & 0xffff;
op = (inst >> 26) & 0x3f;
switch (op) {
case sb_op:
bytes = 1;
if (bytes > sizeof(run->mmio.data)) {
kvm_err("%s: bad MMIO length: %d\n", __func__,
run->mmio.len);
}
run->mmio.phys_addr =
kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
host_cp0_badvaddr);
if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
er = EMULATE_FAIL;
break;
}
run->mmio.len = bytes;
run->mmio.is_write = 1;
vcpu->mmio_needed = 1;
vcpu->mmio_is_write = 1;
*(u8 *) data = vcpu->arch.gprs[rt];
kvm_debug("OP_SB: eaddr: %#lx, gpr: %#lx, data: %#x\n",
vcpu->arch.host_cp0_badvaddr, vcpu->arch.gprs[rt],
*(uint8_t *) data);
break;
case sw_op:
bytes = 4;
if (bytes > sizeof(run->mmio.data)) {
kvm_err("%s: bad MMIO length: %d\n", __func__,
run->mmio.len);
}
run->mmio.phys_addr =
kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
host_cp0_badvaddr);
if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
er = EMULATE_FAIL;
break;
}
run->mmio.len = bytes;
run->mmio.is_write = 1;
vcpu->mmio_needed = 1;
vcpu->mmio_is_write = 1;
*(uint32_t *) data = vcpu->arch.gprs[rt];
kvm_debug("[%#lx] OP_SW: eaddr: %#lx, gpr: %#lx, data: %#x\n",
vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
vcpu->arch.gprs[rt], *(uint32_t *) data);
break;
case sh_op:
bytes = 2;
if (bytes > sizeof(run->mmio.data)) {
kvm_err("%s: bad MMIO length: %d\n", __func__,
run->mmio.len);
}
run->mmio.phys_addr =
kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
host_cp0_badvaddr);
if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
er = EMULATE_FAIL;
break;
}
run->mmio.len = bytes;
run->mmio.is_write = 1;
vcpu->mmio_needed = 1;
vcpu->mmio_is_write = 1;
*(uint16_t *) data = vcpu->arch.gprs[rt];
kvm_debug("[%#lx] OP_SH: eaddr: %#lx, gpr: %#lx, data: %#x\n",
vcpu->arch.pc, vcpu->arch.host_cp0_badvaddr,
vcpu->arch.gprs[rt], *(uint32_t *) data);
break;
default:
kvm_err("Store not yet supported");
er = EMULATE_FAIL;
break;
}
/* Rollback PC if emulation was unsuccessful */
if (er == EMULATE_FAIL)
vcpu->arch.pc = curr_pc;
return er;
}
enum emulation_result kvm_mips_emulate_load(uint32_t inst, uint32_t cause,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
enum emulation_result er = EMULATE_DO_MMIO;
int32_t op, base, rt, offset;
uint32_t bytes;
rt = (inst >> 16) & 0x1f;
base = (inst >> 21) & 0x1f;
offset = inst & 0xffff;
op = (inst >> 26) & 0x3f;
vcpu->arch.pending_load_cause = cause;
vcpu->arch.io_gpr = rt;
switch (op) {
case lw_op:
bytes = 4;
if (bytes > sizeof(run->mmio.data)) {
kvm_err("%s: bad MMIO length: %d\n", __func__,
run->mmio.len);
er = EMULATE_FAIL;
break;
}
run->mmio.phys_addr =
kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
host_cp0_badvaddr);
if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
er = EMULATE_FAIL;
break;
}
run->mmio.len = bytes;
run->mmio.is_write = 0;
vcpu->mmio_needed = 1;
vcpu->mmio_is_write = 0;
break;
case lh_op:
case lhu_op:
bytes = 2;
if (bytes > sizeof(run->mmio.data)) {
kvm_err("%s: bad MMIO length: %d\n", __func__,
run->mmio.len);
er = EMULATE_FAIL;
break;
}
run->mmio.phys_addr =
kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
host_cp0_badvaddr);
if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
er = EMULATE_FAIL;
break;
}
run->mmio.len = bytes;
run->mmio.is_write = 0;
vcpu->mmio_needed = 1;
vcpu->mmio_is_write = 0;
if (op == lh_op)
vcpu->mmio_needed = 2;
else
vcpu->mmio_needed = 1;
break;
case lbu_op:
case lb_op:
bytes = 1;
if (bytes > sizeof(run->mmio.data)) {
kvm_err("%s: bad MMIO length: %d\n", __func__,
run->mmio.len);
er = EMULATE_FAIL;
break;
}
run->mmio.phys_addr =
kvm_mips_callbacks->gva_to_gpa(vcpu->arch.
host_cp0_badvaddr);
if (run->mmio.phys_addr == KVM_INVALID_ADDR) {
er = EMULATE_FAIL;
break;
}
run->mmio.len = bytes;
run->mmio.is_write = 0;
vcpu->mmio_is_write = 0;
if (op == lb_op)
vcpu->mmio_needed = 2;
else
vcpu->mmio_needed = 1;
break;
default:
kvm_err("Load not yet supported");
er = EMULATE_FAIL;
break;
}
return er;
}
int kvm_mips_sync_icache(unsigned long va, struct kvm_vcpu *vcpu)
{
unsigned long offset = (va & ~PAGE_MASK);
struct kvm *kvm = vcpu->kvm;
unsigned long pa;
gfn_t gfn;
kvm_pfn_t pfn;
gfn = va >> PAGE_SHIFT;
if (gfn >= kvm->arch.guest_pmap_npages) {
kvm_err("%s: Invalid gfn: %#llx\n", __func__, gfn);
kvm_mips_dump_host_tlbs();
kvm_arch_vcpu_dump_regs(vcpu);
return -1;
}
pfn = kvm->arch.guest_pmap[gfn];
pa = (pfn << PAGE_SHIFT) | offset;
kvm_debug("%s: va: %#lx, unmapped: %#x\n", __func__, va,
CKSEG0ADDR(pa));
local_flush_icache_range(CKSEG0ADDR(pa), 32);
return 0;
}
enum emulation_result kvm_mips_emulate_cache(uint32_t inst, uint32_t *opc,
uint32_t cause,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
enum emulation_result er = EMULATE_DONE;
int32_t offset, cache, op_inst, op, base;
struct kvm_vcpu_arch *arch = &vcpu->arch;
unsigned long va;
unsigned long curr_pc;
/*
* Update PC and hold onto current PC in case there is
* an error and we want to rollback the PC
*/
curr_pc = vcpu->arch.pc;
er = update_pc(vcpu, cause);
if (er == EMULATE_FAIL)
return er;
base = (inst >> 21) & 0x1f;
op_inst = (inst >> 16) & 0x1f;
offset = (int16_t)inst;
cache = op_inst & CacheOp_Cache;
op = op_inst & CacheOp_Op;
va = arch->gprs[base] + offset;
kvm_debug("CACHE (cache: %#x, op: %#x, base[%d]: %#lx, offset: %#x\n",
cache, op, base, arch->gprs[base], offset);
/*
* Treat INDEX_INV as a nop, basically issued by Linux on startup to
* invalidate the caches entirely by stepping through all the
* ways/indexes
*/
if (op == Index_Writeback_Inv) {
kvm_debug("@ %#lx/%#lx CACHE (cache: %#x, op: %#x, base[%d]: %#lx, offset: %#x\n",
vcpu->arch.pc, vcpu->arch.gprs[31], cache, op, base,
arch->gprs[base], offset);
if (cache == Cache_D)
r4k_blast_dcache();
else if (cache == Cache_I)
r4k_blast_icache();
else {
kvm_err("%s: unsupported CACHE INDEX operation\n",
__func__);
return EMULATE_FAIL;
}
#ifdef CONFIG_KVM_MIPS_DYN_TRANS
kvm_mips_trans_cache_index(inst, opc, vcpu);
#endif
goto done;
}
preempt_disable();
if (KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG0) {
if (kvm_mips_host_tlb_lookup(vcpu, va) < 0)
kvm_mips_handle_kseg0_tlb_fault(va, vcpu);
} else if ((KVM_GUEST_KSEGX(va) < KVM_GUEST_KSEG0) ||
KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG23) {
int index;
/* If an entry already exists then skip */
if (kvm_mips_host_tlb_lookup(vcpu, va) >= 0)
goto skip_fault;
/*
* If address not in the guest TLB, then give the guest a fault,
* the resulting handler will do the right thing
*/
index = kvm_mips_guest_tlb_lookup(vcpu, (va & VPN2_MASK) |
(kvm_read_c0_guest_entryhi
(cop0) & KVM_ENTRYHI_ASID));
if (index < 0) {
vcpu->arch.host_cp0_entryhi = (va & VPN2_MASK);
vcpu->arch.host_cp0_badvaddr = va;
er = kvm_mips_emulate_tlbmiss_ld(cause, NULL, run,
vcpu);
preempt_enable();
goto dont_update_pc;
} else {
struct kvm_mips_tlb *tlb = &vcpu->arch.guest_tlb[index];
/*
* Check if the entry is valid, if not then setup a TLB
* invalid exception to the guest
*/
if (!TLB_IS_VALID(*tlb, va)) {
er = kvm_mips_emulate_tlbinv_ld(cause, NULL,
run, vcpu);
preempt_enable();
goto dont_update_pc;
} else {
/*
* We fault an entry from the guest tlb to the
* shadow host TLB
*/
kvm_mips_handle_mapped_seg_tlb_fault(vcpu, tlb,
NULL,
NULL);
}
}
} else {
kvm_err("INVALID CACHE INDEX/ADDRESS (cache: %#x, op: %#x, base[%d]: %#lx, offset: %#x\n",
cache, op, base, arch->gprs[base], offset);
er = EMULATE_FAIL;
preempt_enable();
goto dont_update_pc;
}
skip_fault:
/* XXXKYMA: Only a subset of cache ops are supported, used by Linux */
if (op_inst == Hit_Writeback_Inv_D || op_inst == Hit_Invalidate_D) {
flush_dcache_line(va);
#ifdef CONFIG_KVM_MIPS_DYN_TRANS
/*
* Replace the CACHE instruction, with a SYNCI, not the same,
* but avoids a trap
*/
kvm_mips_trans_cache_va(inst, opc, vcpu);
#endif
} else if (op_inst == Hit_Invalidate_I) {
flush_dcache_line(va);
flush_icache_line(va);
#ifdef CONFIG_KVM_MIPS_DYN_TRANS
/* Replace the CACHE instruction, with a SYNCI */
kvm_mips_trans_cache_va(inst, opc, vcpu);
#endif
} else {
kvm_err("NO-OP CACHE (cache: %#x, op: %#x, base[%d]: %#lx, offset: %#x\n",
cache, op, base, arch->gprs[base], offset);
er = EMULATE_FAIL;
preempt_enable();
goto dont_update_pc;
}
preempt_enable();
dont_update_pc:
/* Rollback PC */
vcpu->arch.pc = curr_pc;
done:
return er;
}
enum emulation_result kvm_mips_emulate_inst(unsigned long cause, uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
enum emulation_result er = EMULATE_DONE;
uint32_t inst;
/* Fetch the instruction. */
if (cause & CAUSEF_BD)
opc += 1;
inst = kvm_get_inst(opc, vcpu);
switch (((union mips_instruction)inst).r_format.opcode) {
case cop0_op:
er = kvm_mips_emulate_CP0(inst, opc, cause, run, vcpu);
break;
case sb_op:
case sh_op:
case sw_op:
er = kvm_mips_emulate_store(inst, cause, run, vcpu);
break;
case lb_op:
case lbu_op:
case lhu_op:
case lh_op:
case lw_op:
er = kvm_mips_emulate_load(inst, cause, run, vcpu);
break;
case cache_op:
++vcpu->stat.cache_exits;
trace_kvm_exit(vcpu, CACHE_EXITS);
er = kvm_mips_emulate_cache(inst, opc, cause, run, vcpu);
break;
default:
kvm_err("Instruction emulation not supported (%p/%#x)\n", opc,
inst);
kvm_arch_vcpu_dump_regs(vcpu);
er = EMULATE_FAIL;
break;
}
return er;
}
enum emulation_result kvm_mips_emulate_syscall(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
enum emulation_result er = EMULATE_DONE;
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("Delivering SYSCALL @ pc %#lx\n", arch->pc);
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_SYS << CAUSEB_EXCCODE));
/* Set PC to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x180;
} else {
kvm_err("Trying to deliver SYSCALL when EXL is already set\n");
er = EMULATE_FAIL;
}
return er;
}
enum emulation_result kvm_mips_emulate_tlbmiss_ld(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
unsigned long entryhi = (vcpu->arch. host_cp0_badvaddr & VPN2_MASK) |
(kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID);
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("[EXL == 0] delivering TLB MISS @ pc %#lx\n",
arch->pc);
/* set pc to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x0;
} else {
kvm_debug("[EXL == 1] delivering TLB MISS @ pc %#lx\n",
arch->pc);
arch->pc = KVM_GUEST_KSEG0 + 0x180;
}
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_TLBL << CAUSEB_EXCCODE));
/* setup badvaddr, context and entryhi registers for the guest */
kvm_write_c0_guest_badvaddr(cop0, vcpu->arch.host_cp0_badvaddr);
/* XXXKYMA: is the context register used by linux??? */
kvm_write_c0_guest_entryhi(cop0, entryhi);
/* Blow away the shadow host TLBs */
kvm_mips_flush_host_tlb(1);
return EMULATE_DONE;
}
enum emulation_result kvm_mips_emulate_tlbinv_ld(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
unsigned long entryhi =
(vcpu->arch.host_cp0_badvaddr & VPN2_MASK) |
(kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID);
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("[EXL == 0] delivering TLB INV @ pc %#lx\n",
arch->pc);
/* set pc to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x180;
} else {
kvm_debug("[EXL == 1] delivering TLB MISS @ pc %#lx\n",
arch->pc);
arch->pc = KVM_GUEST_KSEG0 + 0x180;
}
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_TLBL << CAUSEB_EXCCODE));
/* setup badvaddr, context and entryhi registers for the guest */
kvm_write_c0_guest_badvaddr(cop0, vcpu->arch.host_cp0_badvaddr);
/* XXXKYMA: is the context register used by linux??? */
kvm_write_c0_guest_entryhi(cop0, entryhi);
/* Blow away the shadow host TLBs */
kvm_mips_flush_host_tlb(1);
return EMULATE_DONE;
}
enum emulation_result kvm_mips_emulate_tlbmiss_st(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
unsigned long entryhi = (vcpu->arch.host_cp0_badvaddr & VPN2_MASK) |
(kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID);
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("[EXL == 0] Delivering TLB MISS @ pc %#lx\n",
arch->pc);
/* Set PC to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x0;
} else {
kvm_debug("[EXL == 1] Delivering TLB MISS @ pc %#lx\n",
arch->pc);
arch->pc = KVM_GUEST_KSEG0 + 0x180;
}
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_TLBS << CAUSEB_EXCCODE));
/* setup badvaddr, context and entryhi registers for the guest */
kvm_write_c0_guest_badvaddr(cop0, vcpu->arch.host_cp0_badvaddr);
/* XXXKYMA: is the context register used by linux??? */
kvm_write_c0_guest_entryhi(cop0, entryhi);
/* Blow away the shadow host TLBs */
kvm_mips_flush_host_tlb(1);
return EMULATE_DONE;
}
enum emulation_result kvm_mips_emulate_tlbinv_st(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
unsigned long entryhi = (vcpu->arch.host_cp0_badvaddr & VPN2_MASK) |
(kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID);
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("[EXL == 0] Delivering TLB MISS @ pc %#lx\n",
arch->pc);
/* Set PC to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x180;
} else {
kvm_debug("[EXL == 1] Delivering TLB MISS @ pc %#lx\n",
arch->pc);
arch->pc = KVM_GUEST_KSEG0 + 0x180;
}
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_TLBS << CAUSEB_EXCCODE));
/* setup badvaddr, context and entryhi registers for the guest */
kvm_write_c0_guest_badvaddr(cop0, vcpu->arch.host_cp0_badvaddr);
/* XXXKYMA: is the context register used by linux??? */
kvm_write_c0_guest_entryhi(cop0, entryhi);
/* Blow away the shadow host TLBs */
kvm_mips_flush_host_tlb(1);
return EMULATE_DONE;
}
/* TLBMOD: store into address matching TLB with Dirty bit off */
enum emulation_result kvm_mips_handle_tlbmod(unsigned long cause, uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
enum emulation_result er = EMULATE_DONE;
#ifdef DEBUG
struct mips_coproc *cop0 = vcpu->arch.cop0;
unsigned long entryhi = (vcpu->arch.host_cp0_badvaddr & VPN2_MASK) |
(kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID);
int index;
/* If address not in the guest TLB, then we are in trouble */
index = kvm_mips_guest_tlb_lookup(vcpu, entryhi);
if (index < 0) {
/* XXXKYMA Invalidate and retry */
kvm_mips_host_tlb_inv(vcpu, vcpu->arch.host_cp0_badvaddr);
kvm_err("%s: host got TLBMOD for %#lx but entry not present in Guest TLB\n",
__func__, entryhi);
kvm_mips_dump_guest_tlbs(vcpu);
kvm_mips_dump_host_tlbs();
return EMULATE_FAIL;
}
#endif
er = kvm_mips_emulate_tlbmod(cause, opc, run, vcpu);
return er;
}
enum emulation_result kvm_mips_emulate_tlbmod(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
unsigned long entryhi = (vcpu->arch.host_cp0_badvaddr & VPN2_MASK) |
(kvm_read_c0_guest_entryhi(cop0) & KVM_ENTRYHI_ASID);
struct kvm_vcpu_arch *arch = &vcpu->arch;
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("[EXL == 0] Delivering TLB MOD @ pc %#lx\n",
arch->pc);
arch->pc = KVM_GUEST_KSEG0 + 0x180;
} else {
kvm_debug("[EXL == 1] Delivering TLB MOD @ pc %#lx\n",
arch->pc);
arch->pc = KVM_GUEST_KSEG0 + 0x180;
}
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_MOD << CAUSEB_EXCCODE));
/* setup badvaddr, context and entryhi registers for the guest */
kvm_write_c0_guest_badvaddr(cop0, vcpu->arch.host_cp0_badvaddr);
/* XXXKYMA: is the context register used by linux??? */
kvm_write_c0_guest_entryhi(cop0, entryhi);
/* Blow away the shadow host TLBs */
kvm_mips_flush_host_tlb(1);
return EMULATE_DONE;
}
enum emulation_result kvm_mips_emulate_fpu_exc(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
}
arch->pc = KVM_GUEST_KSEG0 + 0x180;
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_CPU << CAUSEB_EXCCODE));
kvm_change_c0_guest_cause(cop0, (CAUSEF_CE), (0x1 << CAUSEB_CE));
return EMULATE_DONE;
}
enum emulation_result kvm_mips_emulate_ri_exc(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
enum emulation_result er = EMULATE_DONE;
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("Delivering RI @ pc %#lx\n", arch->pc);
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_RI << CAUSEB_EXCCODE));
/* Set PC to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x180;
} else {
kvm_err("Trying to deliver RI when EXL is already set\n");
er = EMULATE_FAIL;
}
return er;
}
enum emulation_result kvm_mips_emulate_bp_exc(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
enum emulation_result er = EMULATE_DONE;
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("Delivering BP @ pc %#lx\n", arch->pc);
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_BP << CAUSEB_EXCCODE));
/* Set PC to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x180;
} else {
kvm_err("Trying to deliver BP when EXL is already set\n");
er = EMULATE_FAIL;
}
return er;
}
enum emulation_result kvm_mips_emulate_trap_exc(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
enum emulation_result er = EMULATE_DONE;
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("Delivering TRAP @ pc %#lx\n", arch->pc);
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_TR << CAUSEB_EXCCODE));
/* Set PC to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x180;
} else {
kvm_err("Trying to deliver TRAP when EXL is already set\n");
er = EMULATE_FAIL;
}
return er;
}
enum emulation_result kvm_mips_emulate_msafpe_exc(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
enum emulation_result er = EMULATE_DONE;
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("Delivering MSAFPE @ pc %#lx\n", arch->pc);
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_MSAFPE << CAUSEB_EXCCODE));
/* Set PC to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x180;
} else {
kvm_err("Trying to deliver MSAFPE when EXL is already set\n");
er = EMULATE_FAIL;
}
return er;
}
enum emulation_result kvm_mips_emulate_fpe_exc(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
enum emulation_result er = EMULATE_DONE;
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("Delivering FPE @ pc %#lx\n", arch->pc);
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_FPE << CAUSEB_EXCCODE));
/* Set PC to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x180;
} else {
kvm_err("Trying to deliver FPE when EXL is already set\n");
er = EMULATE_FAIL;
}
return er;
}
enum emulation_result kvm_mips_emulate_msadis_exc(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
enum emulation_result er = EMULATE_DONE;
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_debug("Delivering MSADIS @ pc %#lx\n", arch->pc);
kvm_change_c0_guest_cause(cop0, (0xff),
(EXCCODE_MSADIS << CAUSEB_EXCCODE));
/* Set PC to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x180;
} else {
kvm_err("Trying to deliver MSADIS when EXL is already set\n");
er = EMULATE_FAIL;
}
return er;
}
/* ll/sc, rdhwr, sync emulation */
#define OPCODE 0xfc000000
#define BASE 0x03e00000
#define RT 0x001f0000
#define OFFSET 0x0000ffff
#define LL 0xc0000000
#define SC 0xe0000000
#define SPEC0 0x00000000
#define SPEC3 0x7c000000
#define RD 0x0000f800
#define FUNC 0x0000003f
#define SYNC 0x0000000f
#define RDHWR 0x0000003b
enum emulation_result kvm_mips_handle_ri(unsigned long cause, uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
enum emulation_result er = EMULATE_DONE;
unsigned long curr_pc;
uint32_t inst;
/*
* Update PC and hold onto current PC in case there is
* an error and we want to rollback the PC
*/
curr_pc = vcpu->arch.pc;
er = update_pc(vcpu, cause);
if (er == EMULATE_FAIL)
return er;
/* Fetch the instruction. */
if (cause & CAUSEF_BD)
opc += 1;
inst = kvm_get_inst(opc, vcpu);
if (inst == KVM_INVALID_INST) {
kvm_err("%s: Cannot get inst @ %p\n", __func__, opc);
return EMULATE_FAIL;
}
if ((inst & OPCODE) == SPEC3 && (inst & FUNC) == RDHWR) {
int usermode = !KVM_GUEST_KERNEL_MODE(vcpu);
int rd = (inst & RD) >> 11;
int rt = (inst & RT) >> 16;
/* If usermode, check RDHWR rd is allowed by guest HWREna */
if (usermode && !(kvm_read_c0_guest_hwrena(cop0) & BIT(rd))) {
kvm_debug("RDHWR %#x disallowed by HWREna @ %p\n",
rd, opc);
goto emulate_ri;
}
switch (rd) {
case 0: /* CPU number */
arch->gprs[rt] = 0;
break;
case 1: /* SYNCI length */
arch->gprs[rt] = min(current_cpu_data.dcache.linesz,
current_cpu_data.icache.linesz);
break;
case 2: /* Read count register */
arch->gprs[rt] = kvm_mips_read_count(vcpu);
break;
case 3: /* Count register resolution */
switch (current_cpu_data.cputype) {
case CPU_20KC:
case CPU_25KF:
arch->gprs[rt] = 1;
break;
default:
arch->gprs[rt] = 2;
}
break;
case 29:
arch->gprs[rt] = kvm_read_c0_guest_userlocal(cop0);
break;
default:
kvm_debug("RDHWR %#x not supported @ %p\n", rd, opc);
goto emulate_ri;
}
} else {
kvm_debug("Emulate RI not supported @ %p: %#x\n", opc, inst);
goto emulate_ri;
}
return EMULATE_DONE;
emulate_ri:
/*
* Rollback PC (if in branch delay slot then the PC already points to
* branch target), and pass the RI exception to the guest OS.
*/
vcpu->arch.pc = curr_pc;
return kvm_mips_emulate_ri_exc(cause, opc, run, vcpu);
}
enum emulation_result kvm_mips_complete_mmio_load(struct kvm_vcpu *vcpu,
struct kvm_run *run)
{
unsigned long *gpr = &vcpu->arch.gprs[vcpu->arch.io_gpr];
enum emulation_result er = EMULATE_DONE;
if (run->mmio.len > sizeof(*gpr)) {
kvm_err("Bad MMIO length: %d", run->mmio.len);
er = EMULATE_FAIL;
goto done;
}
er = update_pc(vcpu, vcpu->arch.pending_load_cause);
if (er == EMULATE_FAIL)
return er;
switch (run->mmio.len) {
case 4:
*gpr = *(int32_t *) run->mmio.data;
break;
case 2:
if (vcpu->mmio_needed == 2)
*gpr = *(int16_t *) run->mmio.data;
else
*gpr = *(uint16_t *)run->mmio.data;
break;
case 1:
if (vcpu->mmio_needed == 2)
*gpr = *(int8_t *) run->mmio.data;
else
*gpr = *(u8 *) run->mmio.data;
break;
}
if (vcpu->arch.pending_load_cause & CAUSEF_BD)
kvm_debug("[%#lx] Completing %d byte BD Load to gpr %d (0x%08lx) type %d\n",
vcpu->arch.pc, run->mmio.len, vcpu->arch.io_gpr, *gpr,
vcpu->mmio_needed);
done:
return er;
}
static enum emulation_result kvm_mips_emulate_exc(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
uint32_t exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
struct mips_coproc *cop0 = vcpu->arch.cop0;
struct kvm_vcpu_arch *arch = &vcpu->arch;
enum emulation_result er = EMULATE_DONE;
if ((kvm_read_c0_guest_status(cop0) & ST0_EXL) == 0) {
/* save old pc */
kvm_write_c0_guest_epc(cop0, arch->pc);
kvm_set_c0_guest_status(cop0, ST0_EXL);
if (cause & CAUSEF_BD)
kvm_set_c0_guest_cause(cop0, CAUSEF_BD);
else
kvm_clear_c0_guest_cause(cop0, CAUSEF_BD);
kvm_change_c0_guest_cause(cop0, (0xff),
(exccode << CAUSEB_EXCCODE));
/* Set PC to the exception entry point */
arch->pc = KVM_GUEST_KSEG0 + 0x180;
kvm_write_c0_guest_badvaddr(cop0, vcpu->arch.host_cp0_badvaddr);
kvm_debug("Delivering EXC %d @ pc %#lx, badVaddr: %#lx\n",
exccode, kvm_read_c0_guest_epc(cop0),
kvm_read_c0_guest_badvaddr(cop0));
} else {
kvm_err("Trying to deliver EXC when EXL is already set\n");
er = EMULATE_FAIL;
}
return er;
}
enum emulation_result kvm_mips_check_privilege(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
enum emulation_result er = EMULATE_DONE;
uint32_t exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr;
int usermode = !KVM_GUEST_KERNEL_MODE(vcpu);
if (usermode) {
switch (exccode) {
case EXCCODE_INT:
case EXCCODE_SYS:
case EXCCODE_BP:
case EXCCODE_RI:
case EXCCODE_TR:
case EXCCODE_MSAFPE:
case EXCCODE_FPE:
case EXCCODE_MSADIS:
break;
case EXCCODE_CPU:
if (((cause & CAUSEF_CE) >> CAUSEB_CE) == 0)
er = EMULATE_PRIV_FAIL;
break;
case EXCCODE_MOD:
break;
case EXCCODE_TLBL:
/*
* We we are accessing Guest kernel space, then send an
* address error exception to the guest
*/
if (badvaddr >= (unsigned long) KVM_GUEST_KSEG0) {
kvm_debug("%s: LD MISS @ %#lx\n", __func__,
badvaddr);
cause &= ~0xff;
cause |= (EXCCODE_ADEL << CAUSEB_EXCCODE);
er = EMULATE_PRIV_FAIL;
}
break;
case EXCCODE_TLBS:
/*
* We we are accessing Guest kernel space, then send an
* address error exception to the guest
*/
if (badvaddr >= (unsigned long) KVM_GUEST_KSEG0) {
kvm_debug("%s: ST MISS @ %#lx\n", __func__,
badvaddr);
cause &= ~0xff;
cause |= (EXCCODE_ADES << CAUSEB_EXCCODE);
er = EMULATE_PRIV_FAIL;
}
break;
case EXCCODE_ADES:
kvm_debug("%s: address error ST @ %#lx\n", __func__,
badvaddr);
if ((badvaddr & PAGE_MASK) == KVM_GUEST_COMMPAGE_ADDR) {
cause &= ~0xff;
cause |= (EXCCODE_TLBS << CAUSEB_EXCCODE);
}
er = EMULATE_PRIV_FAIL;
break;
case EXCCODE_ADEL:
kvm_debug("%s: address error LD @ %#lx\n", __func__,
badvaddr);
if ((badvaddr & PAGE_MASK) == KVM_GUEST_COMMPAGE_ADDR) {
cause &= ~0xff;
cause |= (EXCCODE_TLBL << CAUSEB_EXCCODE);
}
er = EMULATE_PRIV_FAIL;
break;
default:
er = EMULATE_PRIV_FAIL;
break;
}
}
if (er == EMULATE_PRIV_FAIL)
kvm_mips_emulate_exc(cause, opc, run, vcpu);
return er;
}
/*
* 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
*/
enum emulation_result kvm_mips_handle_tlbmiss(unsigned long cause,
uint32_t *opc,
struct kvm_run *run,
struct kvm_vcpu *vcpu)
{
enum emulation_result er = EMULATE_DONE;
uint32_t exccode = (cause >> CAUSEB_EXCCODE) & 0x1f;
unsigned long va = vcpu->arch.host_cp0_badvaddr;
int index;
kvm_debug("kvm_mips_handle_tlbmiss: badvaddr: %#lx, entryhi: %#lx\n",
vcpu->arch.host_cp0_badvaddr, vcpu->arch.host_cp0_entryhi);
/*
* KVM would not have got the exception if this entry was valid in the
* shadow host TLB. Check the Guest TLB, if the entry is not there then
* send the guest an exception. The guest exc handler should then inject
* an entry into the guest TLB.
*/
index = kvm_mips_guest_tlb_lookup(vcpu,
(va & VPN2_MASK) |
(kvm_read_c0_guest_entryhi(vcpu->arch.cop0) &
KVM_ENTRYHI_ASID));
if (index < 0) {
if (exccode == EXCCODE_TLBL) {
er = kvm_mips_emulate_tlbmiss_ld(cause, opc, run, vcpu);
} else if (exccode == EXCCODE_TLBS) {
er = kvm_mips_emulate_tlbmiss_st(cause, opc, run, vcpu);
} else {
kvm_err("%s: invalid exc code: %d\n", __func__,
exccode);
er = EMULATE_FAIL;
}
} else {
struct kvm_mips_tlb *tlb = &vcpu->arch.guest_tlb[index];
/*
* Check if the entry is valid, if not then setup a TLB invalid
* exception to the guest
*/
if (!TLB_IS_VALID(*tlb, va)) {
if (exccode == EXCCODE_TLBL) {
er = kvm_mips_emulate_tlbinv_ld(cause, opc, run,
vcpu);
} else if (exccode == EXCCODE_TLBS) {
er = kvm_mips_emulate_tlbinv_st(cause, opc, run,
vcpu);
} else {
kvm_err("%s: invalid exc code: %d\n", __func__,
exccode);
er = EMULATE_FAIL;
}
} else {
kvm_debug("Injecting hi: %#lx, lo0: %#lx, lo1: %#lx into shadow host TLB\n",
tlb->tlb_hi, tlb->tlb_lo0, tlb->tlb_lo1);
/*
* OK we have a Guest TLB entry, now inject it into the
* shadow host TLB
*/
kvm_mips_handle_mapped_seg_tlb_fault(vcpu, tlb, NULL,
NULL);
}
}
return er;
}
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