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- /*
- * 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
- */
- #include <linux/cpu.h>
- #include <linux/kvm.h>
- #include <linux/kvm_host.h>
- #include <linux/interrupt.h>
- #include <linux/irq.h>
- #include <linux/uaccess.h>
- #include <clocksource/arm_arch_timer.h>
- #include <asm/arch_timer.h>
- #include <asm/kvm_hyp.h>
- #include <kvm/arm_vgic.h>
- #include <kvm/arm_arch_timer.h>
- #include "trace.h"
- static struct timecounter *timecounter;
- static unsigned int host_vtimer_irq;
- static u32 host_vtimer_irq_flags;
- static const struct kvm_irq_level default_ptimer_irq = {
- .irq = 30,
- .level = 1,
- };
- static const struct kvm_irq_level default_vtimer_irq = {
- .irq = 27,
- .level = 1,
- };
- void kvm_timer_vcpu_put(struct kvm_vcpu *vcpu)
- {
- vcpu_vtimer(vcpu)->active_cleared_last = false;
- }
- u64 kvm_phys_timer_read(void)
- {
- return timecounter->cc->read(timecounter->cc);
- }
- static bool timer_is_armed(struct arch_timer_cpu *timer)
- {
- return timer->armed;
- }
- /* timer_arm: as in "arm the timer", not as in ARM the company */
- static void timer_arm(struct arch_timer_cpu *timer, u64 ns)
- {
- timer->armed = true;
- hrtimer_start(&timer->timer, ktime_add_ns(ktime_get(), ns),
- HRTIMER_MODE_ABS);
- }
- static void timer_disarm(struct arch_timer_cpu *timer)
- {
- if (timer_is_armed(timer)) {
- hrtimer_cancel(&timer->timer);
- cancel_work_sync(&timer->expired);
- timer->armed = false;
- }
- }
- static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id)
- {
- struct kvm_vcpu *vcpu = *(struct kvm_vcpu **)dev_id;
- /*
- * We disable the timer in the world switch and let it be
- * handled by kvm_timer_sync_hwstate(). Getting a timer
- * interrupt at this point is a sure sign of some major
- * breakage.
- */
- pr_warn("Unexpected interrupt %d on vcpu %p\n", irq, vcpu);
- return IRQ_HANDLED;
- }
- /*
- * Work function for handling the backup timer that we schedule when a vcpu is
- * no longer running, but had a timer programmed to fire in the future.
- */
- static void kvm_timer_inject_irq_work(struct work_struct *work)
- {
- struct kvm_vcpu *vcpu;
- vcpu = container_of(work, struct kvm_vcpu, arch.timer_cpu.expired);
- /*
- * If the vcpu is blocked we want to wake it up so that it will see
- * the timer has expired when entering the guest.
- */
- kvm_vcpu_wake_up(vcpu);
- }
- static u64 kvm_timer_compute_delta(struct arch_timer_context *timer_ctx)
- {
- u64 cval, now;
- cval = timer_ctx->cnt_cval;
- now = kvm_phys_timer_read() - timer_ctx->cntvoff;
- if (now < cval) {
- u64 ns;
- ns = cyclecounter_cyc2ns(timecounter->cc,
- cval - now,
- timecounter->mask,
- &timecounter->frac);
- return ns;
- }
- return 0;
- }
- static bool kvm_timer_irq_can_fire(struct arch_timer_context *timer_ctx)
- {
- return !(timer_ctx->cnt_ctl & ARCH_TIMER_CTRL_IT_MASK) &&
- (timer_ctx->cnt_ctl & ARCH_TIMER_CTRL_ENABLE);
- }
- /*
- * Returns the earliest expiration time in ns among guest timers.
- * Note that it will return 0 if none of timers can fire.
- */
- static u64 kvm_timer_earliest_exp(struct kvm_vcpu *vcpu)
- {
- u64 min_virt = ULLONG_MAX, min_phys = ULLONG_MAX;
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
- if (kvm_timer_irq_can_fire(vtimer))
- min_virt = kvm_timer_compute_delta(vtimer);
- if (kvm_timer_irq_can_fire(ptimer))
- min_phys = kvm_timer_compute_delta(ptimer);
- /* If none of timers can fire, then return 0 */
- if ((min_virt == ULLONG_MAX) && (min_phys == ULLONG_MAX))
- return 0;
- return min(min_virt, min_phys);
- }
- static enum hrtimer_restart kvm_timer_expire(struct hrtimer *hrt)
- {
- struct arch_timer_cpu *timer;
- struct kvm_vcpu *vcpu;
- u64 ns;
- timer = container_of(hrt, struct arch_timer_cpu, timer);
- vcpu = container_of(timer, struct kvm_vcpu, arch.timer_cpu);
- /*
- * Check that the timer has really expired from the guest's
- * PoV (NTP on the host may have forced it to expire
- * early). If we should have slept longer, restart it.
- */
- ns = kvm_timer_earliest_exp(vcpu);
- if (unlikely(ns)) {
- hrtimer_forward_now(hrt, ns_to_ktime(ns));
- return HRTIMER_RESTART;
- }
- schedule_work(&timer->expired);
- return HRTIMER_NORESTART;
- }
- bool kvm_timer_should_fire(struct arch_timer_context *timer_ctx)
- {
- u64 cval, now;
- if (!kvm_timer_irq_can_fire(timer_ctx))
- return false;
- cval = timer_ctx->cnt_cval;
- now = kvm_phys_timer_read() - timer_ctx->cntvoff;
- return cval <= now;
- }
- /*
- * Reflect the timer output level into the kvm_run structure
- */
- void kvm_timer_update_run(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
- struct kvm_sync_regs *regs = &vcpu->run->s.regs;
- /* Populate the device bitmap with the timer states */
- regs->device_irq_level &= ~(KVM_ARM_DEV_EL1_VTIMER |
- KVM_ARM_DEV_EL1_PTIMER);
- if (vtimer->irq.level)
- regs->device_irq_level |= KVM_ARM_DEV_EL1_VTIMER;
- if (ptimer->irq.level)
- regs->device_irq_level |= KVM_ARM_DEV_EL1_PTIMER;
- }
- static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level,
- struct arch_timer_context *timer_ctx)
- {
- int ret;
- timer_ctx->active_cleared_last = false;
- timer_ctx->irq.level = new_level;
- trace_kvm_timer_update_irq(vcpu->vcpu_id, timer_ctx->irq.irq,
- timer_ctx->irq.level);
- if (likely(irqchip_in_kernel(vcpu->kvm))) {
- ret = kvm_vgic_inject_irq(vcpu->kvm, vcpu->vcpu_id,
- timer_ctx->irq.irq,
- timer_ctx->irq.level,
- timer_ctx);
- WARN_ON(ret);
- }
- }
- /*
- * Check if there was a change in the timer state (should we raise or lower
- * the line level to the GIC).
- */
- static void kvm_timer_update_state(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
- /*
- * If userspace modified the timer registers via SET_ONE_REG before
- * the vgic was initialized, we mustn't set the vtimer->irq.level value
- * because the guest would never see the interrupt. Instead wait
- * until we call this function from kvm_timer_flush_hwstate.
- */
- if (unlikely(!timer->enabled))
- return;
- if (kvm_timer_should_fire(vtimer) != vtimer->irq.level)
- kvm_timer_update_irq(vcpu, !vtimer->irq.level, vtimer);
- if (kvm_timer_should_fire(ptimer) != ptimer->irq.level)
- kvm_timer_update_irq(vcpu, !ptimer->irq.level, ptimer);
- }
- /* Schedule the background timer for the emulated timer. */
- static void kvm_timer_emulate(struct kvm_vcpu *vcpu,
- struct arch_timer_context *timer_ctx)
- {
- struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
- if (kvm_timer_should_fire(timer_ctx))
- return;
- if (!kvm_timer_irq_can_fire(timer_ctx))
- return;
- /* The timer has not yet expired, schedule a background timer */
- timer_arm(timer, kvm_timer_compute_delta(timer_ctx));
- }
- /*
- * Schedule the background timer before calling kvm_vcpu_block, so that this
- * thread is removed from its waitqueue and made runnable when there's a timer
- * interrupt to handle.
- */
- void kvm_timer_schedule(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
- BUG_ON(timer_is_armed(timer));
- /*
- * No need to schedule a background timer if any guest timer has
- * already expired, because kvm_vcpu_block will return before putting
- * the thread to sleep.
- */
- if (kvm_timer_should_fire(vtimer) || kvm_timer_should_fire(ptimer))
- return;
- /*
- * If both timers are not capable of raising interrupts (disabled or
- * masked), then there's no more work for us to do.
- */
- if (!kvm_timer_irq_can_fire(vtimer) && !kvm_timer_irq_can_fire(ptimer))
- return;
- /*
- * The guest timers have not yet expired, schedule a background timer.
- * Set the earliest expiration time among the guest timers.
- */
- timer_arm(timer, kvm_timer_earliest_exp(vcpu));
- }
- void kvm_timer_unschedule(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
- timer_disarm(timer);
- }
- static void kvm_timer_flush_hwstate_vgic(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- bool phys_active;
- int ret;
- /*
- * If we enter the guest with the virtual input level to the VGIC
- * asserted, then we have already told the VGIC what we need to, and
- * we don't need to exit from the guest until the guest deactivates
- * the already injected interrupt, so therefore we should set the
- * hardware active state to prevent unnecessary exits from the guest.
- *
- * Also, if we enter the guest with the virtual timer interrupt active,
- * then it must be active on the physical distributor, because we set
- * the HW bit and the guest must be able to deactivate the virtual and
- * physical interrupt at the same time.
- *
- * Conversely, if the virtual input level is deasserted and the virtual
- * interrupt is not active, then always clear the hardware active state
- * to ensure that hardware interrupts from the timer triggers a guest
- * exit.
- */
- phys_active = vtimer->irq.level ||
- kvm_vgic_map_is_active(vcpu, vtimer->irq.irq);
- /*
- * We want to avoid hitting the (re)distributor as much as
- * possible, as this is a potentially expensive MMIO access
- * (not to mention locks in the irq layer), and a solution for
- * this is to cache the "active" state in memory.
- *
- * Things to consider: we cannot cache an "active set" state,
- * because the HW can change this behind our back (it becomes
- * "clear" in the HW). We must then restrict the caching to
- * the "clear" state.
- *
- * The cache is invalidated on:
- * - vcpu put, indicating that the HW cannot be trusted to be
- * in a sane state on the next vcpu load,
- * - any change in the interrupt state
- *
- * Usage conditions:
- * - cached value is "active clear"
- * - value to be programmed is "active clear"
- */
- if (vtimer->active_cleared_last && !phys_active)
- return;
- ret = irq_set_irqchip_state(host_vtimer_irq,
- IRQCHIP_STATE_ACTIVE,
- phys_active);
- WARN_ON(ret);
- vtimer->active_cleared_last = !phys_active;
- }
- bool kvm_timer_should_notify_user(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
- struct kvm_sync_regs *sregs = &vcpu->run->s.regs;
- bool vlevel, plevel;
- if (likely(irqchip_in_kernel(vcpu->kvm)))
- return false;
- vlevel = sregs->device_irq_level & KVM_ARM_DEV_EL1_VTIMER;
- plevel = sregs->device_irq_level & KVM_ARM_DEV_EL1_PTIMER;
- return vtimer->irq.level != vlevel ||
- ptimer->irq.level != plevel;
- }
- static void kvm_timer_flush_hwstate_user(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- /*
- * To prevent continuously exiting from the guest, we mask the
- * physical interrupt such that the guest can make forward progress.
- * Once we detect the output level being deasserted, we unmask the
- * interrupt again so that we exit from the guest when the timer
- * fires.
- */
- if (vtimer->irq.level)
- disable_percpu_irq(host_vtimer_irq);
- else
- enable_percpu_irq(host_vtimer_irq, 0);
- }
- /**
- * kvm_timer_flush_hwstate - prepare timers before running the vcpu
- * @vcpu: The vcpu pointer
- *
- * Check if the virtual timer has expired while we were running in the host,
- * and inject an interrupt if that was the case, making sure the timer is
- * masked or disabled on the host so that we keep executing. Also schedule a
- * software timer for the physical timer if it is enabled.
- */
- void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
- if (unlikely(!timer->enabled))
- return;
- kvm_timer_update_state(vcpu);
- /* Set the background timer for the physical timer emulation. */
- kvm_timer_emulate(vcpu, vcpu_ptimer(vcpu));
- if (unlikely(!irqchip_in_kernel(vcpu->kvm)))
- kvm_timer_flush_hwstate_user(vcpu);
- else
- kvm_timer_flush_hwstate_vgic(vcpu);
- }
- /**
- * kvm_timer_sync_hwstate - sync timer state from cpu
- * @vcpu: The vcpu pointer
- *
- * Check if any of the timers have expired while we were running in the guest,
- * and inject an interrupt if that was the case.
- */
- void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
- /*
- * This is to cancel the background timer for the physical timer
- * emulation if it is set.
- */
- timer_disarm(timer);
- /*
- * The guest could have modified the timer registers or the timer
- * could have expired, update the timer state.
- */
- kvm_timer_update_state(vcpu);
- }
- int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
- /*
- * The bits in CNTV_CTL are architecturally reset to UNKNOWN for ARMv8
- * and to 0 for ARMv7. We provide an implementation that always
- * resets the timer to be disabled and unmasked and is compliant with
- * the ARMv7 architecture.
- */
- vtimer->cnt_ctl = 0;
- ptimer->cnt_ctl = 0;
- kvm_timer_update_state(vcpu);
- return 0;
- }
- /* Make the updates of cntvoff for all vtimer contexts atomic */
- static void update_vtimer_cntvoff(struct kvm_vcpu *vcpu, u64 cntvoff)
- {
- int i;
- struct kvm *kvm = vcpu->kvm;
- struct kvm_vcpu *tmp;
- mutex_lock(&kvm->lock);
- kvm_for_each_vcpu(i, tmp, kvm)
- vcpu_vtimer(tmp)->cntvoff = cntvoff;
- /*
- * When called from the vcpu create path, the CPU being created is not
- * included in the loop above, so we just set it here as well.
- */
- vcpu_vtimer(vcpu)->cntvoff = cntvoff;
- mutex_unlock(&kvm->lock);
- }
- void kvm_timer_vcpu_init(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
- /* Synchronize cntvoff across all vtimers of a VM. */
- update_vtimer_cntvoff(vcpu, kvm_phys_timer_read());
- vcpu_ptimer(vcpu)->cntvoff = 0;
- INIT_WORK(&timer->expired, kvm_timer_inject_irq_work);
- hrtimer_init(&timer->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
- timer->timer.function = kvm_timer_expire;
- vtimer->irq.irq = default_vtimer_irq.irq;
- ptimer->irq.irq = default_ptimer_irq.irq;
- }
- static void kvm_timer_init_interrupt(void *info)
- {
- enable_percpu_irq(host_vtimer_irq, host_vtimer_irq_flags);
- }
- int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value)
- {
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- switch (regid) {
- case KVM_REG_ARM_TIMER_CTL:
- vtimer->cnt_ctl = value;
- break;
- case KVM_REG_ARM_TIMER_CNT:
- update_vtimer_cntvoff(vcpu, kvm_phys_timer_read() - value);
- break;
- case KVM_REG_ARM_TIMER_CVAL:
- vtimer->cnt_cval = value;
- break;
- default:
- return -1;
- }
- kvm_timer_update_state(vcpu);
- return 0;
- }
- u64 kvm_arm_timer_get_reg(struct kvm_vcpu *vcpu, u64 regid)
- {
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- switch (regid) {
- case KVM_REG_ARM_TIMER_CTL:
- return vtimer->cnt_ctl;
- case KVM_REG_ARM_TIMER_CNT:
- return kvm_phys_timer_read() - vtimer->cntvoff;
- case KVM_REG_ARM_TIMER_CVAL:
- return vtimer->cnt_cval;
- }
- return (u64)-1;
- }
- static int kvm_timer_starting_cpu(unsigned int cpu)
- {
- kvm_timer_init_interrupt(NULL);
- return 0;
- }
- static int kvm_timer_dying_cpu(unsigned int cpu)
- {
- disable_percpu_irq(host_vtimer_irq);
- return 0;
- }
- int kvm_timer_hyp_init(void)
- {
- struct arch_timer_kvm_info *info;
- int err;
- info = arch_timer_get_kvm_info();
- timecounter = &info->timecounter;
- if (!timecounter->cc) {
- kvm_err("kvm_arch_timer: uninitialized timecounter\n");
- return -ENODEV;
- }
- if (info->virtual_irq <= 0) {
- kvm_err("kvm_arch_timer: invalid virtual timer IRQ: %d\n",
- info->virtual_irq);
- return -ENODEV;
- }
- host_vtimer_irq = info->virtual_irq;
- host_vtimer_irq_flags = irq_get_trigger_type(host_vtimer_irq);
- if (host_vtimer_irq_flags != IRQF_TRIGGER_HIGH &&
- host_vtimer_irq_flags != IRQF_TRIGGER_LOW) {
- kvm_err("Invalid trigger for IRQ%d, assuming level low\n",
- host_vtimer_irq);
- host_vtimer_irq_flags = IRQF_TRIGGER_LOW;
- }
- err = request_percpu_irq(host_vtimer_irq, kvm_arch_timer_handler,
- "kvm guest timer", kvm_get_running_vcpus());
- if (err) {
- kvm_err("kvm_arch_timer: can't request interrupt %d (%d)\n",
- host_vtimer_irq, err);
- return err;
- }
- kvm_debug("virtual timer IRQ%d\n", host_vtimer_irq);
- cpuhp_setup_state(CPUHP_AP_KVM_ARM_TIMER_STARTING,
- "kvm/arm/timer:starting", kvm_timer_starting_cpu,
- kvm_timer_dying_cpu);
- return err;
- }
- void kvm_timer_vcpu_terminate(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- timer_disarm(timer);
- kvm_vgic_unmap_phys_irq(vcpu, vtimer->irq.irq);
- }
- static bool timer_irqs_are_valid(struct kvm_vcpu *vcpu)
- {
- int vtimer_irq, ptimer_irq;
- int i, ret;
- vtimer_irq = vcpu_vtimer(vcpu)->irq.irq;
- ret = kvm_vgic_set_owner(vcpu, vtimer_irq, vcpu_vtimer(vcpu));
- if (ret)
- return false;
- ptimer_irq = vcpu_ptimer(vcpu)->irq.irq;
- ret = kvm_vgic_set_owner(vcpu, ptimer_irq, vcpu_ptimer(vcpu));
- if (ret)
- return false;
- kvm_for_each_vcpu(i, vcpu, vcpu->kvm) {
- if (vcpu_vtimer(vcpu)->irq.irq != vtimer_irq ||
- vcpu_ptimer(vcpu)->irq.irq != ptimer_irq)
- return false;
- }
- return true;
- }
- int kvm_timer_enable(struct kvm_vcpu *vcpu)
- {
- struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu;
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- struct irq_desc *desc;
- struct irq_data *data;
- int phys_irq;
- int ret;
- if (timer->enabled)
- return 0;
- /* Without a VGIC we do not map virtual IRQs to physical IRQs */
- if (!irqchip_in_kernel(vcpu->kvm))
- goto no_vgic;
- if (!vgic_initialized(vcpu->kvm))
- return -ENODEV;
- if (!timer_irqs_are_valid(vcpu)) {
- kvm_debug("incorrectly configured timer irqs\n");
- return -EINVAL;
- }
- /*
- * Find the physical IRQ number corresponding to the host_vtimer_irq
- */
- desc = irq_to_desc(host_vtimer_irq);
- if (!desc) {
- kvm_err("%s: no interrupt descriptor\n", __func__);
- return -EINVAL;
- }
- data = irq_desc_get_irq_data(desc);
- while (data->parent_data)
- data = data->parent_data;
- phys_irq = data->hwirq;
- /*
- * Tell the VGIC that the virtual interrupt is tied to a
- * physical interrupt. We do that once per VCPU.
- */
- ret = kvm_vgic_map_phys_irq(vcpu, vtimer->irq.irq, phys_irq);
- if (ret)
- return ret;
- no_vgic:
- timer->enabled = 1;
- return 0;
- }
- /*
- * On VHE system, we only need to configure trap on physical timer and counter
- * accesses in EL0 and EL1 once, not for every world switch.
- * The host kernel runs at EL2 with HCR_EL2.TGE == 1,
- * and this makes those bits have no effect for the host kernel execution.
- */
- void kvm_timer_init_vhe(void)
- {
- /* When HCR_EL2.E2H ==1, EL1PCEN and EL1PCTEN are shifted by 10 */
- u32 cnthctl_shift = 10;
- u64 val;
- /*
- * Disallow physical timer access for the guest.
- * Physical counter access is allowed.
- */
- val = read_sysreg(cnthctl_el2);
- val &= ~(CNTHCTL_EL1PCEN << cnthctl_shift);
- val |= (CNTHCTL_EL1PCTEN << cnthctl_shift);
- write_sysreg(val, cnthctl_el2);
- }
- static void set_timer_irqs(struct kvm *kvm, int vtimer_irq, int ptimer_irq)
- {
- struct kvm_vcpu *vcpu;
- int i;
- kvm_for_each_vcpu(i, vcpu, kvm) {
- vcpu_vtimer(vcpu)->irq.irq = vtimer_irq;
- vcpu_ptimer(vcpu)->irq.irq = ptimer_irq;
- }
- }
- int kvm_arm_timer_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
- {
- int __user *uaddr = (int __user *)(long)attr->addr;
- struct arch_timer_context *vtimer = vcpu_vtimer(vcpu);
- struct arch_timer_context *ptimer = vcpu_ptimer(vcpu);
- int irq;
- if (!irqchip_in_kernel(vcpu->kvm))
- return -EINVAL;
- if (get_user(irq, uaddr))
- return -EFAULT;
- if (!(irq_is_ppi(irq)))
- return -EINVAL;
- if (vcpu->arch.timer_cpu.enabled)
- return -EBUSY;
- switch (attr->attr) {
- case KVM_ARM_VCPU_TIMER_IRQ_VTIMER:
- set_timer_irqs(vcpu->kvm, irq, ptimer->irq.irq);
- break;
- case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
- set_timer_irqs(vcpu->kvm, vtimer->irq.irq, irq);
- break;
- default:
- return -ENXIO;
- }
- return 0;
- }
- int kvm_arm_timer_get_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
- {
- int __user *uaddr = (int __user *)(long)attr->addr;
- struct arch_timer_context *timer;
- int irq;
- switch (attr->attr) {
- case KVM_ARM_VCPU_TIMER_IRQ_VTIMER:
- timer = vcpu_vtimer(vcpu);
- break;
- case KVM_ARM_VCPU_TIMER_IRQ_PTIMER:
- timer = vcpu_ptimer(vcpu);
- break;
- default:
- return -ENXIO;
- }
- irq = timer->irq.irq;
- return put_user(irq, uaddr);
- }
- 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:
- return 0;
- }
- return -ENXIO;
- }
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