Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...

[karo-tx-linux.git] / virt / kvm / arm / vgic.c

diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c
index 77b0176b04841301ac9ec2801791f57b57741cf3..30489181922d28d9749feefb552e7b8f0fa97f52 100644 (file)
--- a/virt/kvm/arm/vgic.c
+++ b/virt/kvm/arm/vgic.c
@@ -531,6 +531,34 @@ 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+ * is no longer active or pending, without it have gone through the sync path,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)
@@ -561,6 +589,7 @@ 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;
        }
@@ -598,6 +627,7 @@ 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;
        }
@@ -982,6 +1012,12 @@ static int compute_pending_for_cpu(struct kvm_vcpu *vcpu)
        pend_percpu = vcpu->arch.vgic_cpu.pending_percpu;
        pend_shared = vcpu->arch.vgic_cpu.pending_shared;
 
+       if (!dist->enabled) {
+               bitmap_zero(pend_percpu, VGIC_NR_PRIVATE_IRQS);
+               bitmap_zero(pend_shared, nr_shared);
+               return 0;
+       }
+
        pending = vgic_bitmap_get_cpu_map(&dist->irq_pending, vcpu_id);
        enabled = vgic_bitmap_get_cpu_map(&dist->irq_enabled, vcpu_id);
        bitmap_and(pend_percpu, pending, enabled, VGIC_NR_PRIVATE_IRQS);
@@ -1009,11 +1045,6 @@ void vgic_update_state(struct kvm *kvm)
        struct kvm_vcpu *vcpu;
        int c;
 
-       if (!dist->enabled) {
-               set_bit(0, dist->irq_pending_on_cpu);
-               return;
-       }
-
        kvm_for_each_vcpu(c, vcpu, kvm) {
                if (compute_pending_for_cpu(vcpu))
                        set_bit(c, dist->irq_pending_on_cpu);
@@ -1092,6 +1123,15 @@ static void vgic_retire_lr(int lr_nr, int irq, struct kvm_vcpu *vcpu)
        struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        struct vgic_lr vlr = vgic_get_lr(vcpu, lr_nr);
 
+       /*
+        * We must transfer the pending state back to the distributor before
+        * retiring the LR, otherwise we may loose edge-triggered interrupts.
+        */
+       if (vlr.state & LR_STATE_PENDING) {
+               vgic_dist_irq_set_pending(vcpu, irq);
+               vlr.hwirq = 0;
+       }
+
        vlr.state = 0;
        vgic_set_lr(vcpu, lr_nr, vlr);
        clear_bit(lr_nr, vgic_cpu->lr_used);
@@ -1132,7 +1172,8 @@ static void vgic_queue_irq_to_lr(struct kvm_vcpu *vcpu, int irq,
                kvm_debug("Set active, clear distributor: 0x%x\n", vlr.state);
                vgic_irq_clear_active(vcpu, irq);
                vgic_update_state(vcpu->kvm);
-       } else if (vgic_dist_irq_is_pending(vcpu, irq)) {
+       } else {
+               WARN_ON(!vgic_dist_irq_is_pending(vcpu, irq));
                vlr.state |= LR_STATE_PENDING;
                kvm_debug("Set pending: 0x%x\n", vlr.state);
        }
@@ -1240,7 +1281,7 @@ static void __kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu)
        struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu;
        struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
        unsigned long *pa_percpu, *pa_shared;
-       int i, vcpu_id, lr, ret;
+       int i, vcpu_id;
        int overflow = 0;
        int nr_shared = vgic_nr_shared_irqs(dist);
 
@@ -1295,31 +1336,6 @@ epilog:
                 */
                clear_bit(vcpu_id, dist->irq_pending_on_cpu);
        }
-
-       for (lr = 0; lr < vgic->nr_lr; lr++) {
-               struct vgic_lr vlr;
-
-               if (!test_bit(lr, vgic_cpu->lr_used))
-                       continue;
-
-               vlr = vgic_get_lr(vcpu, lr);
-
-               /*
-                * If we have a mapping, and the virtual interrupt is
-                * presented to the guest (as pending or active), then we must
-                * set the state to active in the physical world. See
-                * Documentation/virtual/kvm/arm/vgic-mapped-irqs.txt.
-                */
-               if (vlr.state & LR_HW) {
-                       struct irq_phys_map *map;
-                       map = vgic_irq_map_search(vcpu, vlr.irq);
-
-                       ret = irq_set_irqchip_state(map->irq,
-                                                   IRQCHIP_STATE_ACTIVE,
-                                                   true);
-                       WARN_ON(ret);
-               }
-       }
 }
 
 static bool vgic_process_maintenance(struct kvm_vcpu *vcpu)
@@ -1421,7 +1437,7 @@ static int vgic_sync_hwirq(struct kvm_vcpu *vcpu, struct vgic_lr vlr)
                return 0;
 
        map = vgic_irq_map_search(vcpu, vlr.irq);
-       BUG_ON(!map || !map->active);
+       BUG_ON(!map);
 
        ret = irq_get_irqchip_state(map->irq,
                                    IRQCHIP_STATE_ACTIVE,
@@ -1429,13 +1445,8 @@ static int vgic_sync_hwirq(struct kvm_vcpu *vcpu, struct vgic_lr vlr)
 
        WARN_ON(ret);
 
-       if (map->active) {
-               ret = irq_set_irqchip_state(map->irq,
-                                           IRQCHIP_STATE_ACTIVE,
-                                           false);
-               WARN_ON(ret);
+       if (map->active)
                return 0;
-       }
 
        return 1;
 }
@@ -1607,8 +1618,12 @@ static int vgic_update_irq_pending(struct kvm *kvm, int cpuid,
        } else {
                if (level_triggered) {
                        vgic_dist_irq_clear_level(vcpu, irq_num);
-                       if (!vgic_dist_irq_soft_pend(vcpu, irq_num))
+                       if (!vgic_dist_irq_soft_pend(vcpu, irq_num)) {
                                vgic_dist_irq_clear_pending(vcpu, irq_num);
+                               vgic_cpu_irq_clear(vcpu, irq_num);
+                               if (!compute_pending_for_cpu(vcpu))
+                                       clear_bit(cpuid, dist->irq_pending_on_cpu);
+                       }
                }
 
                ret = false;