kernel-ark/arch/x86/kvm/irq.c
Yang Zhang c7c9c56ca2 x86, apicv: add virtual interrupt delivery support
Virtual interrupt delivery avoids KVM to inject vAPIC interrupts
manually, which is fully taken care of by the hardware. This needs
some special awareness into existing interrupr injection path:

- for pending interrupt, instead of direct injection, we may need
  update architecture specific indicators before resuming to guest.

- A pending interrupt, which is masked by ISR, should be also
  considered in above update action, since hardware will decide
  when to inject it at right time. Current has_interrupt and
  get_interrupt only returns a valid vector from injection p.o.v.

Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>
2013-01-29 10:48:19 +02:00

129 lines
3.0 KiB
C

/*
* irq.c: API for in kernel interrupt controller
* Copyright (c) 2007, Intel Corporation.
* Copyright 2009 Red Hat, Inc. and/or its affiliates.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place - Suite 330, Boston, MA 02111-1307 USA.
* Authors:
* Yaozu (Eddie) Dong <Eddie.dong@intel.com>
*
*/
#include <linux/module.h>
#include <linux/kvm_host.h>
#include "irq.h"
#include "i8254.h"
#include "x86.h"
/*
* check if there are pending timer events
* to be processed.
*/
int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
{
return apic_has_pending_timer(vcpu);
}
EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
/*
* check if there is pending interrupt from
* non-APIC source without intack.
*/
static int kvm_cpu_has_extint(struct kvm_vcpu *v)
{
if (kvm_apic_accept_pic_intr(v))
return pic_irqchip(v->kvm)->output; /* PIC */
else
return 0;
}
/*
* check if there is injectable interrupt:
* when virtual interrupt delivery enabled,
* interrupt from apic will handled by hardware,
* we don't need to check it here.
*/
int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v)
{
if (!irqchip_in_kernel(v->kvm))
return v->arch.interrupt.pending;
if (kvm_cpu_has_extint(v))
return 1;
if (kvm_apic_vid_enabled(v->kvm))
return 0;
return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
}
/*
* check if there is pending interrupt without
* intack.
*/
int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
{
if (!irqchip_in_kernel(v->kvm))
return v->arch.interrupt.pending;
if (kvm_cpu_has_extint(v))
return 1;
return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
}
EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
/*
* Read pending interrupt(from non-APIC source)
* vector and intack.
*/
static int kvm_cpu_get_extint(struct kvm_vcpu *v)
{
if (kvm_cpu_has_extint(v))
return kvm_pic_read_irq(v->kvm); /* PIC */
return -1;
}
/*
* Read pending interrupt vector and intack.
*/
int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
{
int vector;
if (!irqchip_in_kernel(v->kvm))
return v->arch.interrupt.nr;
vector = kvm_cpu_get_extint(v);
if (kvm_apic_vid_enabled(v->kvm) || vector != -1)
return vector; /* PIC */
return kvm_get_apic_interrupt(v); /* APIC */
}
void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
{
kvm_inject_apic_timer_irqs(vcpu);
/* TODO: PIT, RTC etc. */
}
EXPORT_SYMBOL_GPL(kvm_inject_pending_timer_irqs);
void __kvm_migrate_timers(struct kvm_vcpu *vcpu)
{
__kvm_migrate_apic_timer(vcpu);
__kvm_migrate_pit_timer(vcpu);
}