diff options
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/arm/arch_timer.c | 81 | ||||
| -rw-r--r-- | virt/kvm/arm/vgic.c | 102 |
2 files changed, 82 insertions, 101 deletions
diff --git a/virt/kvm/arm/arch_timer.c b/virt/kvm/arm/arch_timer.c index 32095fbb5d7c..523816d8c402 100644 --- a/virt/kvm/arm/arch_timer.c +++ b/virt/kvm/arm/arch_timer.c @@ -59,18 +59,6 @@ static void timer_disarm(struct arch_timer_cpu *timer) } } -static void kvm_timer_inject_irq(struct kvm_vcpu *vcpu) -{ - int ret; - struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; - - kvm_vgic_set_phys_irq_active(timer->map, true); - ret = kvm_vgic_inject_mapped_irq(vcpu->kvm, vcpu->vcpu_id, - timer->map, - timer->irq->level); - WARN_ON(ret); -} - static irqreturn_t kvm_arch_timer_handler(int irq, void *dev_id) { struct kvm_vcpu *vcpu = *(struct kvm_vcpu **)dev_id; @@ -116,8 +104,7 @@ static bool kvm_timer_irq_can_fire(struct kvm_vcpu *vcpu) struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; return !(timer->cntv_ctl & ARCH_TIMER_CTRL_IT_MASK) && - (timer->cntv_ctl & ARCH_TIMER_CTRL_ENABLE) && - !kvm_vgic_get_phys_irq_active(timer->map); + (timer->cntv_ctl & ARCH_TIMER_CTRL_ENABLE); } bool kvm_timer_should_fire(struct kvm_vcpu *vcpu) @@ -134,6 +121,41 @@ bool kvm_timer_should_fire(struct kvm_vcpu *vcpu) return cval <= now; } +static void kvm_timer_update_irq(struct kvm_vcpu *vcpu, bool new_level) +{ + int ret; + struct arch_timer_cpu *timer = &vcpu->arch.timer_cpu; + + BUG_ON(!vgic_initialized(vcpu->kvm)); + + timer->irq.level = new_level; + ret = kvm_vgic_inject_mapped_irq(vcpu->kvm, vcpu->vcpu_id, + timer->map, + timer->irq.level); + 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; + + /* + * If userspace modified the timer registers via SET_ONE_REG before + * the vgic was initialized, we mustn't set the timer->irq.level value + * because the guest would never see the interrupt. Instead wait + * until we call this function from kvm_timer_flush_hwstate. + */ + if (!vgic_initialized(vcpu->kvm)) + return; + + if (kvm_timer_should_fire(vcpu) != timer->irq.level) + kvm_timer_update_irq(vcpu, !timer->irq.level); +} + /* * 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 @@ -192,17 +214,20 @@ void kvm_timer_flush_hwstate(struct kvm_vcpu *vcpu) bool phys_active; int ret; - if (kvm_timer_should_fire(vcpu)) - kvm_timer_inject_irq(vcpu); + kvm_timer_update_state(vcpu); /* - * We keep track of whether the edge-triggered interrupt has been - * signalled to the vgic/guest, and if so, we mask the interrupt and - * the physical distributor to prevent the timer from raising a - * physical interrupt whenever we run a guest, preventing forward - * VCPU progress. + * 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. + * + * Conversely, if the virtual input level is deasserted, then always + * clear the hardware active state to ensure that hardware interrupts + * from the timer triggers a guest exit. */ - if (kvm_vgic_get_phys_irq_active(timer->map)) + if (timer->irq.level) phys_active = true; else phys_active = false; @@ -226,8 +251,11 @@ void kvm_timer_sync_hwstate(struct kvm_vcpu *vcpu) BUG_ON(timer_is_armed(timer)); - if (kvm_timer_should_fire(vcpu)) - kvm_timer_inject_irq(vcpu); + /* + * 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, @@ -242,7 +270,7 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu, * kvm_vcpu_set_target(). To handle this, we determine * vcpu timer irq number when the vcpu is reset. */ - timer->irq = irq; + timer->irq.irq = irq->irq; /* * The bits in CNTV_CTL are architecturally reset to UNKNOWN for ARMv8 @@ -251,6 +279,7 @@ int kvm_timer_vcpu_reset(struct kvm_vcpu *vcpu, * the ARMv7 architecture. */ timer->cntv_ctl = 0; + kvm_timer_update_state(vcpu); /* * Tell the VGIC that the virtual interrupt is tied to a @@ -295,6 +324,8 @@ int kvm_arm_timer_set_reg(struct kvm_vcpu *vcpu, u64 regid, u64 value) default: return -1; } + + kvm_timer_update_state(vcpu); return 0; } diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index a44ecf9eca4e..3c2909c1bda3 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -537,34 +537,6 @@ bool vgic_handle_set_pending_reg(struct kvm *kvm, return false; } -/* - * If a mapped interrupt's state has been modified by the guest such that it - * is no longer active or pending, without it have gone through the sync path, - * then the map->active field must be cleared so the interrupt can be taken - * again. - */ -static void vgic_handle_clear_mapped_irq(struct kvm_vcpu *vcpu) -{ - struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; - struct list_head *root; - struct irq_phys_map_entry *entry; - struct irq_phys_map *map; - - rcu_read_lock(); - - /* Check for PPIs */ - root = &vgic_cpu->irq_phys_map_list; - list_for_each_entry_rcu(entry, root, entry) { - map = &entry->map; - - if (!vgic_dist_irq_is_pending(vcpu, map->virt_irq) && - !vgic_irq_is_active(vcpu, map->virt_irq)) - map->active = false; - } - - rcu_read_unlock(); -} - bool vgic_handle_clear_pending_reg(struct kvm *kvm, struct kvm_exit_mmio *mmio, phys_addr_t offset, int vcpu_id) @@ -595,7 +567,6 @@ bool vgic_handle_clear_pending_reg(struct kvm *kvm, vcpu_id, offset); vgic_reg_access(mmio, reg, offset, mode); - vgic_handle_clear_mapped_irq(kvm_get_vcpu(kvm, vcpu_id)); vgic_update_state(kvm); return true; } @@ -633,7 +604,6 @@ bool vgic_handle_clear_active_reg(struct kvm *kvm, ACCESS_READ_VALUE | ACCESS_WRITE_CLEARBIT); if (mmio->is_write) { - vgic_handle_clear_mapped_irq(kvm_get_vcpu(kvm, vcpu_id)); vgic_update_state(kvm); return true; } @@ -1443,29 +1413,37 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) /* * Save the physical active state, and reset it to inactive. * - * Return 1 if HW interrupt went from active to inactive, and 0 otherwise. + * Return true if there's a pending level triggered interrupt line to queue. */ -static int vgic_sync_hwirq(struct kvm_vcpu *vcpu, struct vgic_lr vlr) +static bool vgic_sync_hwirq(struct kvm_vcpu *vcpu, int lr, struct vgic_lr vlr) { + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; struct irq_phys_map *map; + bool phys_active; + bool level_pending; int ret; if (!(vlr.state & LR_HW)) - return 0; + return false; map = vgic_irq_map_search(vcpu, vlr.irq); BUG_ON(!map); ret = irq_get_irqchip_state(map->irq, IRQCHIP_STATE_ACTIVE, - &map->active); + &phys_active); WARN_ON(ret); - if (map->active) + if (phys_active) return 0; - return 1; + /* Mapped edge-triggered interrupts not yet supported. */ + WARN_ON(vgic_irq_is_edge(vcpu, vlr.irq)); + spin_lock(&dist->lock); + level_pending = process_level_irq(vcpu, lr, vlr); + spin_unlock(&dist->lock); + return level_pending; } /* Sync back the VGIC state after a guest run */ @@ -1490,18 +1468,8 @@ static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) continue; vlr = vgic_get_lr(vcpu, lr); - if (vgic_sync_hwirq(vcpu, vlr)) { - /* - * So this is a HW interrupt that the guest - * EOI-ed. Clean the LR state and allow the - * interrupt to be sampled again. - */ - vlr.state = 0; - vlr.hwirq = 0; - vgic_set_lr(vcpu, lr, vlr); - vgic_irq_clear_queued(vcpu, vlr.irq); - set_bit(lr, elrsr_ptr); - } + if (vgic_sync_hwirq(vcpu, lr, vlr)) + level_pending = true; if (!test_bit(lr, elrsr_ptr)) continue; @@ -1881,30 +1849,6 @@ static void vgic_free_phys_irq_map_rcu(struct rcu_head *rcu) } /** - * kvm_vgic_get_phys_irq_active - Return the active state of a mapped IRQ - * - * Return the logical active state of a mapped interrupt. This doesn't - * necessarily reflects the current HW state. - */ -bool kvm_vgic_get_phys_irq_active(struct irq_phys_map *map) -{ - BUG_ON(!map); - return map->active; -} - -/** - * kvm_vgic_set_phys_irq_active - Set the active state of a mapped IRQ - * - * Set the logical active state of a mapped interrupt. This doesn't - * immediately affects the HW state. - */ -void kvm_vgic_set_phys_irq_active(struct irq_phys_map *map, bool active) -{ - BUG_ON(!map); - map->active = active; -} - -/** * kvm_vgic_unmap_phys_irq - Remove a virtual to physical IRQ mapping * @vcpu: The VCPU pointer * @map: The pointer to a mapping obtained through kvm_vgic_map_phys_irq @@ -2129,17 +2073,23 @@ int vgic_init(struct kvm *kvm) } /* - * Enable all SGIs and configure all private IRQs as - * edge-triggered. + * Enable and configure all SGIs to be edge-triggere and + * configure all PPIs as level-triggered. */ for (i = 0; i < VGIC_NR_PRIVATE_IRQS; i++) { - if (i < VGIC_NR_SGIS) + if (i < VGIC_NR_SGIS) { + /* SGIs */ vgic_bitmap_set_irq_val(&dist->irq_enabled, vcpu->vcpu_id, i, 1); - if (i < VGIC_NR_PRIVATE_IRQS) vgic_bitmap_set_irq_val(&dist->irq_cfg, vcpu->vcpu_id, i, VGIC_CFG_EDGE); + } else if (i < VGIC_NR_PRIVATE_IRQS) { + /* PPIs */ + vgic_bitmap_set_irq_val(&dist->irq_cfg, + vcpu->vcpu_id, i, + VGIC_CFG_LEVEL); + } } vgic_enable(vcpu); |