linux/include/kvm/arm_arch_timer.h
Christoffer Dall 05971120fc arm/arm64: KVM: Require in-kernel vgic for the arch timers
It is curently possible to run a VM with architected timers support
without creating an in-kernel VGIC, which will result in interrupts from
the virtual timer going nowhere.

To address this issue, move the architected timers initialization to the
time when we run a VCPU for the first time, and then only initialize
(and enable) the architected timers if we have a properly created and
initialized in-kernel VGIC.

When injecting interrupts from the virtual timer to the vgic, the
current setup should ensure that this never calls an on-demand init of
the VGIC, which is the only call path that could return an error from
kvm_vgic_inject_irq(), so capture the return value and raise a warning
if there's an error there.

We also change the kvm_timer_init() function from returning an int to be
a void function, since the function always succeeds.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-15 11:50:42 +01:00

102 lines
2.8 KiB
C

/*
* Copyright (C) 2012 ARM Ltd.
* Author: Marc Zyngier <marc.zyngier@arm.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that 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
*/
#ifndef __ASM_ARM_KVM_ARCH_TIMER_H
#define __ASM_ARM_KVM_ARCH_TIMER_H
#include <linux/clocksource.h>
#include <linux/hrtimer.h>
#include <linux/workqueue.h>
struct arch_timer_kvm {
#ifdef CONFIG_KVM_ARM_TIMER
/* Is the timer enabled */
bool enabled;
/* Virtual offset */
cycle_t cntvoff;
#endif
};
struct arch_timer_cpu {
#ifdef CONFIG_KVM_ARM_TIMER
/* Registers: control register, timer value */
u32 cntv_ctl; /* Saved/restored */
cycle_t cntv_cval; /* Saved/restored */
/*
* Anything that is not used directly from assembly code goes
* here.
*/
/* Background timer used when the guest is not running */
struct hrtimer timer;
/* Work queued with the above timer expires */
struct work_struct expired;
/* Background timer active */
bool armed;
/* Timer IRQ */
const struct kvm_irq_level *irq;
#endif
};
#ifdef CONFIG_KVM_ARM_TIMER
int kvm_timer_hyp_init(void);
void kvm_timer_enable(struct kvm *kvm);
void kvm_timer_init(struct kvm *kvm);
void kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
const struct kvm_irq_level *irq);
void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu);
void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu);
void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu);
void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu);
u64 kvm_arm_timer_get_reg(struct kvm_vcpu *, u64 regid);
int kvm_arm_timer_set_reg(struct kvm_vcpu *, u64 regid, u64 value);
#else
static inline int kvm_timer_hyp_init(void)
{
return 0;
};
static inline void kvm_timer_enable(struct kvm *kvm) {}
static inline void kvm_timer_init(struct kvm *kvm) {}
static inline void kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu,
const struct kvm_irq_level *irq) {}
static inline void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu) {}
static inline void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu) {}
static inline void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) {}
static inline void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu) {}
static inline int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value)
{
return 0;
}
static inline u64 kvm_arm_timer_get_reg(struct kvm_vcpu *vcpu, u64 regid)
{
return 0;
}
#endif
#endif