KVM: arm64: nv: timers: Support hyp timer emulation

Emulating EL2 also means emulating the EL2 timers. To do so, we expand
our timer framework to deal with at most 4 timers. At any given time,
two timers are using the HW timers, and the two others are purely
emulated.

The role of deciding which is which at any given time is left to a
mapping function which is called every time we need to make such a
decision.

Reviewed-by: Colton Lewis <coltonlewis@google.com>
Co-developed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230330174800.2677007-18-maz@kernel.org
This commit is contained in:
Marc Zyngier 2023-03-30 18:47:57 +01:00
parent 1e0eec09d4
commit 81dc9504a7
8 changed files with 220 additions and 12 deletions

View File

@ -369,6 +369,10 @@ enum vcpu_sysreg {
TPIDR_EL2, /* EL2 Software Thread ID Register */
CNTHCTL_EL2, /* Counter-timer Hypervisor Control register */
SP_EL2, /* EL2 Stack Pointer */
CNTHP_CTL_EL2,
CNTHP_CVAL_EL2,
CNTHV_CTL_EL2,
CNTHV_CVAL_EL2,
NR_SYS_REGS /* Nothing after this line! */
};

View File

@ -420,6 +420,8 @@ enum {
#define KVM_ARM_VCPU_TIMER_CTRL 1
#define KVM_ARM_VCPU_TIMER_IRQ_VTIMER 0
#define KVM_ARM_VCPU_TIMER_IRQ_PTIMER 1
#define KVM_ARM_VCPU_TIMER_IRQ_HVTIMER 2
#define KVM_ARM_VCPU_TIMER_IRQ_HPTIMER 3
#define KVM_ARM_VCPU_PVTIME_CTRL 2
#define KVM_ARM_VCPU_PVTIME_IPA 0

View File

@ -16,6 +16,7 @@
#include <asm/arch_timer.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_hyp.h>
#include <asm/kvm_nested.h>
#include <kvm/arm_vgic.h>
#include <kvm/arm_arch_timer.h>
@ -33,6 +34,8 @@ static DEFINE_STATIC_KEY_FALSE(has_gic_active_state);
static const u8 default_ppi[] = {
[TIMER_PTIMER] = 30,
[TIMER_VTIMER] = 27,
[TIMER_HPTIMER] = 26,
[TIMER_HVTIMER] = 28,
};
static bool kvm_timer_irq_can_fire(struct arch_timer_context *timer_ctx);
@ -46,6 +49,11 @@ static void kvm_arm_timer_write(struct kvm_vcpu *vcpu,
static u64 kvm_arm_timer_read(struct kvm_vcpu *vcpu,
struct arch_timer_context *timer,
enum kvm_arch_timer_regs treg);
static bool kvm_arch_timer_get_input_level(int vintid);
static struct irq_ops arch_timer_irq_ops = {
.get_input_level = kvm_arch_timer_get_input_level,
};
static bool has_cntpoff(void)
{
@ -54,6 +62,9 @@ static bool has_cntpoff(void)
static int nr_timers(struct kvm_vcpu *vcpu)
{
if (!vcpu_has_nv(vcpu))
return NR_KVM_EL0_TIMERS;
return NR_KVM_TIMERS;
}
@ -66,6 +77,10 @@ u32 timer_get_ctl(struct arch_timer_context *ctxt)
return __vcpu_sys_reg(vcpu, CNTV_CTL_EL0);
case TIMER_PTIMER:
return __vcpu_sys_reg(vcpu, CNTP_CTL_EL0);
case TIMER_HVTIMER:
return __vcpu_sys_reg(vcpu, CNTHV_CTL_EL2);
case TIMER_HPTIMER:
return __vcpu_sys_reg(vcpu, CNTHP_CTL_EL2);
default:
WARN_ON(1);
return 0;
@ -81,6 +96,10 @@ u64 timer_get_cval(struct arch_timer_context *ctxt)
return __vcpu_sys_reg(vcpu, CNTV_CVAL_EL0);
case TIMER_PTIMER:
return __vcpu_sys_reg(vcpu, CNTP_CVAL_EL0);
case TIMER_HVTIMER:
return __vcpu_sys_reg(vcpu, CNTHV_CVAL_EL2);
case TIMER_HPTIMER:
return __vcpu_sys_reg(vcpu, CNTHP_CVAL_EL2);
default:
WARN_ON(1);
return 0;
@ -113,6 +132,12 @@ static void timer_set_ctl(struct arch_timer_context *ctxt, u32 ctl)
case TIMER_PTIMER:
__vcpu_sys_reg(vcpu, CNTP_CTL_EL0) = ctl;
break;
case TIMER_HVTIMER:
__vcpu_sys_reg(vcpu, CNTHV_CTL_EL2) = ctl;
break;
case TIMER_HPTIMER:
__vcpu_sys_reg(vcpu, CNTHP_CTL_EL2) = ctl;
break;
default:
WARN_ON(1);
}
@ -129,6 +154,12 @@ static void timer_set_cval(struct arch_timer_context *ctxt, u64 cval)
case TIMER_PTIMER:
__vcpu_sys_reg(vcpu, CNTP_CVAL_EL0) = cval;
break;
case TIMER_HVTIMER:
__vcpu_sys_reg(vcpu, CNTHV_CVAL_EL2) = cval;
break;
case TIMER_HPTIMER:
__vcpu_sys_reg(vcpu, CNTHP_CVAL_EL2) = cval;
break;
default:
WARN_ON(1);
}
@ -151,13 +182,27 @@ u64 kvm_phys_timer_read(void)
static void get_timer_map(struct kvm_vcpu *vcpu, struct timer_map *map)
{
if (has_vhe()) {
if (vcpu_has_nv(vcpu)) {
if (is_hyp_ctxt(vcpu)) {
map->direct_vtimer = vcpu_hvtimer(vcpu);
map->direct_ptimer = vcpu_hptimer(vcpu);
map->emul_vtimer = vcpu_vtimer(vcpu);
map->emul_ptimer = vcpu_ptimer(vcpu);
} else {
map->direct_vtimer = vcpu_vtimer(vcpu);
map->direct_ptimer = vcpu_ptimer(vcpu);
map->emul_vtimer = vcpu_hvtimer(vcpu);
map->emul_ptimer = vcpu_hptimer(vcpu);
}
} else if (has_vhe()) {
map->direct_vtimer = vcpu_vtimer(vcpu);
map->direct_ptimer = vcpu_ptimer(vcpu);
map->emul_vtimer = NULL;
map->emul_ptimer = NULL;
} else {
map->direct_vtimer = vcpu_vtimer(vcpu);
map->direct_ptimer = NULL;
map->emul_vtimer = NULL;
map->emul_ptimer = vcpu_ptimer(vcpu);
}
@ -252,8 +297,11 @@ static bool vcpu_has_wfit_active(struct kvm_vcpu *vcpu)
static u64 wfit_delay_ns(struct kvm_vcpu *vcpu)
{
struct arch_timer_context *ctx = vcpu_vtimer(vcpu);
u64 val = vcpu_get_reg(vcpu, kvm_vcpu_sys_get_rt(vcpu));
struct arch_timer_context *ctx;
ctx = (vcpu_has_nv(vcpu) && is_hyp_ctxt(vcpu)) ? vcpu_hvtimer(vcpu)
: vcpu_vtimer(vcpu);
return kvm_counter_compute_delta(ctx, val);
}
@ -350,9 +398,11 @@ static bool kvm_timer_should_fire(struct arch_timer_context *timer_ctx)
switch (index) {
case TIMER_VTIMER:
case TIMER_HVTIMER:
cnt_ctl = read_sysreg_el0(SYS_CNTV_CTL);
break;
case TIMER_PTIMER:
case TIMER_HPTIMER:
cnt_ctl = read_sysreg_el0(SYS_CNTP_CTL);
break;
case NR_KVM_TIMERS:
@ -468,6 +518,7 @@ static void timer_save_state(struct arch_timer_context *ctx)
u64 cval;
case TIMER_VTIMER:
case TIMER_HVTIMER:
timer_set_ctl(ctx, read_sysreg_el0(SYS_CNTV_CTL));
timer_set_cval(ctx, read_sysreg_el0(SYS_CNTV_CVAL));
@ -493,6 +544,7 @@ static void timer_save_state(struct arch_timer_context *ctx)
set_cntvoff(0);
break;
case TIMER_PTIMER:
case TIMER_HPTIMER:
timer_set_ctl(ctx, read_sysreg_el0(SYS_CNTP_CTL));
cval = read_sysreg_el0(SYS_CNTP_CVAL);
@ -536,6 +588,7 @@ static void kvm_timer_blocking(struct kvm_vcpu *vcpu)
*/
if (!kvm_timer_irq_can_fire(map.direct_vtimer) &&
!kvm_timer_irq_can_fire(map.direct_ptimer) &&
!kvm_timer_irq_can_fire(map.emul_vtimer) &&
!kvm_timer_irq_can_fire(map.emul_ptimer) &&
!vcpu_has_wfit_active(vcpu))
return;
@ -572,12 +625,14 @@ static void timer_restore_state(struct arch_timer_context *ctx)
u64 cval, offset;
case TIMER_VTIMER:
case TIMER_HVTIMER:
set_cntvoff(timer_get_offset(ctx));
write_sysreg_el0(timer_get_cval(ctx), SYS_CNTV_CVAL);
isb();
write_sysreg_el0(timer_get_ctl(ctx), SYS_CNTV_CTL);
break;
case TIMER_PTIMER:
case TIMER_HPTIMER:
cval = timer_get_cval(ctx);
offset = timer_get_offset(ctx);
set_cntpoff(offset);
@ -663,6 +718,57 @@ static void kvm_timer_vcpu_load_nogic(struct kvm_vcpu *vcpu)
(_clr) |= (_bit); \
} while (0)
static void kvm_timer_vcpu_load_nested_switch(struct kvm_vcpu *vcpu,
struct timer_map *map)
{
int hw, ret;
if (!irqchip_in_kernel(vcpu->kvm))
return;
/*
* We only ever unmap the vtimer irq on a VHE system that runs nested
* virtualization, in which case we have both a valid emul_vtimer,
* emul_ptimer, direct_vtimer, and direct_ptimer.
*
* Since this is called from kvm_timer_vcpu_load(), a change between
* vEL2 and vEL1/0 will have just happened, and the timer_map will
* represent this, and therefore we switch the emul/direct mappings
* below.
*/
hw = kvm_vgic_get_map(vcpu, timer_irq(map->direct_vtimer));
if (hw < 0) {
kvm_vgic_unmap_phys_irq(vcpu, timer_irq(map->emul_vtimer));
kvm_vgic_unmap_phys_irq(vcpu, timer_irq(map->emul_ptimer));
ret = kvm_vgic_map_phys_irq(vcpu,
map->direct_vtimer->host_timer_irq,
timer_irq(map->direct_vtimer),
&arch_timer_irq_ops);
WARN_ON_ONCE(ret);
ret = kvm_vgic_map_phys_irq(vcpu,
map->direct_ptimer->host_timer_irq,
timer_irq(map->direct_ptimer),
&arch_timer_irq_ops);
WARN_ON_ONCE(ret);
/*
* The virtual offset behaviour is "interresting", as it
* always applies when HCR_EL2.E2H==0, but only when
* accessed from EL1 when HCR_EL2.E2H==1. So make sure we
* track E2H when putting the HV timer in "direct" mode.
*/
if (map->direct_vtimer == vcpu_hvtimer(vcpu)) {
struct arch_timer_offset *offs = &map->direct_vtimer->offset;
if (vcpu_el2_e2h_is_set(vcpu))
offs->vcpu_offset = NULL;
else
offs->vcpu_offset = &__vcpu_sys_reg(vcpu, CNTVOFF_EL2);
}
}
}
static void timer_set_traps(struct kvm_vcpu *vcpu, struct timer_map *map)
{
bool tpt, tpc;
@ -695,6 +801,22 @@ static void timer_set_traps(struct kvm_vcpu *vcpu, struct timer_map *map)
if (!has_cntpoff() && timer_get_offset(map->direct_ptimer))
tpt = tpc = true;
/*
* Apply the enable bits that the guest hypervisor has requested for
* its own guest. We can only add traps that wouldn't have been set
* above.
*/
if (vcpu_has_nv(vcpu) && !is_hyp_ctxt(vcpu)) {
u64 val = __vcpu_sys_reg(vcpu, CNTHCTL_EL2);
/* Use the VHE format for mental sanity */
if (!vcpu_el2_e2h_is_set(vcpu))
val = (val & (CNTHCTL_EL1PCEN | CNTHCTL_EL1PCTEN)) << 10;
tpt |= !(val & (CNTHCTL_EL1PCEN << 10));
tpc |= !(val & (CNTHCTL_EL1PCTEN << 10));
}
/*
* Now that we have collected our requirements, compute the
* trap and enable bits.
@ -720,6 +842,9 @@ void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu)
get_timer_map(vcpu, &map);
if (static_branch_likely(&has_gic_active_state)) {
if (vcpu_has_nv(vcpu))
kvm_timer_vcpu_load_nested_switch(vcpu, &map);
kvm_timer_vcpu_load_gic(map.direct_vtimer);
if (map.direct_ptimer)
kvm_timer_vcpu_load_gic(map.direct_ptimer);
@ -732,6 +857,8 @@ void kvm_timer_vcpu_load(struct kvm_vcpu *vcpu)
timer_restore_state(map.direct_vtimer);
if (map.direct_ptimer)
timer_restore_state(map.direct_ptimer);
if (map.emul_vtimer)
timer_emulate(map.emul_vtimer);
if (map.emul_ptimer)
timer_emulate(map.emul_ptimer);
@ -778,6 +905,8 @@ void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu)
* In any case, we re-schedule the hrtimer for the physical timer when
* coming back to the VCPU thread in kvm_timer_vcpu_load().
*/
if (map.emul_vtimer)
soft_timer_cancel(&map.emul_vtimer->hrtimer);
if (map.emul_ptimer)
soft_timer_cancel(&map.emul_ptimer->hrtimer);
@ -830,6 +959,17 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
for (int i = 0; i < nr_timers(vcpu); i++)
timer_set_ctl(vcpu_get_timer(vcpu, i), 0);
/*
* A vcpu running at EL2 is in charge of the offset applied to
* the virtual timer, so use the physical VM offset, and point
* the vcpu offset to CNTVOFF_EL2.
*/
if (vcpu_has_nv(vcpu)) {
struct arch_timer_offset *offs = &vcpu_vtimer(vcpu)->offset;
offs->vcpu_offset = &__vcpu_sys_reg(vcpu, CNTVOFF_EL2);
offs->vm_offset = &vcpu->kvm->arch.timer_data.poffset;
}
if (timer->enabled) {
for (int i = 0; i < nr_timers(vcpu); i++)
@ -843,6 +983,8 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
}
}
if (map.emul_vtimer)
soft_timer_cancel(&map.emul_vtimer->hrtimer);
if (map.emul_ptimer)
soft_timer_cancel(&map.emul_ptimer->hrtimer);
@ -866,9 +1008,11 @@ static void timer_context_init(struct kvm_vcpu *vcpu, int timerid)
switch (timerid) {
case TIMER_PTIMER:
case TIMER_HPTIMER:
ctxt->host_timer_irq = host_ptimer_irq;
break;
case TIMER_VTIMER:
case TIMER_HVTIMER:
ctxt->host_timer_irq = host_vtimer_irq;
break;
}
@ -1020,6 +1164,10 @@ static u64 kvm_arm_timer_read(struct kvm_vcpu *vcpu,
val = kvm_phys_timer_read() - timer_get_offset(timer);
break;
case TIMER_REG_VOFF:
val = *timer->offset.vcpu_offset;
break;
default:
BUG();
}
@ -1038,7 +1186,7 @@ u64 kvm_arm_timer_read_sysreg(struct kvm_vcpu *vcpu,
get_timer_map(vcpu, &map);
timer = vcpu_get_timer(vcpu, tmr);
if (timer == map.emul_ptimer)
if (timer == map.emul_vtimer || timer == map.emul_ptimer)
return kvm_arm_timer_read(vcpu, timer, treg);
preempt_disable();
@ -1070,6 +1218,10 @@ static void kvm_arm_timer_write(struct kvm_vcpu *vcpu,
timer_set_cval(timer, val);
break;
case TIMER_REG_VOFF:
*timer->offset.vcpu_offset = val;
break;
default:
BUG();
}
@ -1085,7 +1237,7 @@ void kvm_arm_timer_write_sysreg(struct kvm_vcpu *vcpu,
get_timer_map(vcpu, &map);
timer = vcpu_get_timer(vcpu, tmr);
if (timer == map.emul_ptimer) {
if (timer == map.emul_vtimer || timer == map.emul_ptimer) {
soft_timer_cancel(&timer->hrtimer);
kvm_arm_timer_write(vcpu, timer, treg, val);
timer_emulate(timer);
@ -1165,10 +1317,6 @@ static const struct irq_domain_ops timer_domain_ops = {
.free = timer_irq_domain_free,
};
static struct irq_ops arch_timer_irq_ops = {
.get_input_level = kvm_arch_timer_get_input_level,
};
static void kvm_irq_fixup_flags(unsigned int virq, u32 *flags)
{
*flags = irq_get_trigger_type(virq);
@ -1341,7 +1489,7 @@ static bool timer_irqs_are_valid(struct kvm_vcpu *vcpu)
return valid;
}
bool kvm_arch_timer_get_input_level(int vintid)
static bool kvm_arch_timer_get_input_level(int vintid)
{
struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
@ -1444,6 +1592,12 @@ int kvm_arm_timer_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
idx = TIMER_PTIMER;
break;
case KVM_ARM_VCPU_TIMER_IRQ_HVTIMER:
idx = TIMER_HVTIMER;
break;
case KVM_ARM_VCPU_TIMER_IRQ_HPTIMER:
idx = TIMER_HPTIMER;
break;
default:
ret = -ENXIO;
goto out;
@ -1474,6 +1628,12 @@ int kvm_arm_timer_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
timer = vcpu_ptimer(vcpu);
break;
case KVM_ARM_VCPU_TIMER_IRQ_HVTIMER:
timer = vcpu_hvtimer(vcpu);
break;
case KVM_ARM_VCPU_TIMER_IRQ_HPTIMER:
timer = vcpu_hptimer(vcpu);
break;
default:
return -ENXIO;
}
@ -1487,6 +1647,8 @@ int kvm_arm_timer_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
switch (attr->attr) {
case KVM_ARM_VCPU_TIMER_IRQ_VTIMER:
case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
case KVM_ARM_VCPU_TIMER_IRQ_HVTIMER:
case KVM_ARM_VCPU_TIMER_IRQ_HPTIMER:
return 0;
}

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@ -343,6 +343,21 @@ static bool kvm_hyp_handle_cntpct(struct kvm_vcpu *vcpu)
switch (sysreg) {
case SYS_CNTPCT_EL0:
case SYS_CNTPCTSS_EL0:
if (vcpu_has_nv(vcpu)) {
if (is_hyp_ctxt(vcpu)) {
ctxt = vcpu_hptimer(vcpu);
break;
}
/* Check for guest hypervisor trapping */
val = __vcpu_sys_reg(vcpu, CNTHCTL_EL2);
if (!vcpu_el2_e2h_is_set(vcpu))
val = (val & CNTHCTL_EL1PCTEN) << 10;
if (!(val & (CNTHCTL_EL1PCTEN << 10)))
return false;
}
ctxt = vcpu_ptimer(vcpu);
break;
default:

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@ -206,6 +206,7 @@ TRACE_EVENT(kvm_get_timer_map,
__field( unsigned long, vcpu_id )
__field( int, direct_vtimer )
__field( int, direct_ptimer )
__field( int, emul_vtimer )
__field( int, emul_ptimer )
),
@ -214,14 +215,17 @@ TRACE_EVENT(kvm_get_timer_map,
__entry->direct_vtimer = arch_timer_ctx_index(map->direct_vtimer);
__entry->direct_ptimer =
(map->direct_ptimer) ? arch_timer_ctx_index(map->direct_ptimer) : -1;
__entry->emul_vtimer =
(map->emul_vtimer) ? arch_timer_ctx_index(map->emul_vtimer) : -1;
__entry->emul_ptimer =
(map->emul_ptimer) ? arch_timer_ctx_index(map->emul_ptimer) : -1;
),
TP_printk("VCPU: %ld, dv: %d, dp: %d, ep: %d",
TP_printk("VCPU: %ld, dv: %d, dp: %d, ev: %d, ep: %d",
__entry->vcpu_id,
__entry->direct_vtimer,
__entry->direct_ptimer,
__entry->emul_vtimer,
__entry->emul_ptimer)
);

View File

@ -573,6 +573,21 @@ int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int vintid)
return 0;
}
int kvm_vgic_get_map(struct kvm_vcpu *vcpu, unsigned int vintid)
{
struct vgic_irq *irq = vgic_get_irq(vcpu->kvm, vcpu, vintid);
unsigned long flags;
int ret = -1;
raw_spin_lock_irqsave(&irq->irq_lock, flags);
if (irq->hw)
ret = irq->hwintid;
raw_spin_unlock_irqrestore(&irq->irq_lock, flags);
vgic_put_irq(vcpu->kvm, irq);
return ret;
}
/**
* kvm_vgic_set_owner - Set the owner of an interrupt for a VM
*

View File

@ -13,6 +13,9 @@
enum kvm_arch_timers {
TIMER_PTIMER,
TIMER_VTIMER,
NR_KVM_EL0_TIMERS,
TIMER_HVTIMER = NR_KVM_EL0_TIMERS,
TIMER_HPTIMER,
NR_KVM_TIMERS
};
@ -21,6 +24,7 @@ enum kvm_arch_timer_regs {
TIMER_REG_CVAL,
TIMER_REG_TVAL,
TIMER_REG_CTL,
TIMER_REG_VOFF,
};
struct arch_timer_offset {
@ -76,6 +80,7 @@ struct arch_timer_context {
struct timer_map {
struct arch_timer_context *direct_vtimer;
struct arch_timer_context *direct_ptimer;
struct arch_timer_context *emul_vtimer;
struct arch_timer_context *emul_ptimer;
};
@ -114,12 +119,12 @@ void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu);
void kvm_timer_init_vhe(void);
bool kvm_arch_timer_get_input_level(int vintid);
#define vcpu_timer(v) (&(v)->arch.timer_cpu)
#define vcpu_get_timer(v,t) (&vcpu_timer(v)->timers[(t)])
#define vcpu_vtimer(v) (&(v)->arch.timer_cpu.timers[TIMER_VTIMER])
#define vcpu_ptimer(v) (&(v)->arch.timer_cpu.timers[TIMER_PTIMER])
#define vcpu_hvtimer(v) (&(v)->arch.timer_cpu.timers[TIMER_HVTIMER])
#define vcpu_hptimer(v) (&(v)->arch.timer_cpu.timers[TIMER_HPTIMER])
#define arch_timer_ctx_index(ctx) ((ctx) - vcpu_timer((ctx)->vcpu)->timers)

View File

@ -380,6 +380,7 @@ int kvm_vgic_inject_irq(struct kvm *kvm, int cpuid, unsigned int intid,
int kvm_vgic_map_phys_irq(struct kvm_vcpu *vcpu, unsigned int host_irq,
u32 vintid, struct irq_ops *ops);
int kvm_vgic_unmap_phys_irq(struct kvm_vcpu *vcpu, unsigned int vintid);
int kvm_vgic_get_map(struct kvm_vcpu *vcpu, unsigned int vintid);
bool kvm_vgic_map_is_active(struct kvm_vcpu *vcpu, unsigned int vintid);
int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu);