KVM: arm64: vgic-v3: vgic_v3_lpi_sync_pending_status

[karo-tx-linux.git] / virt / kvm / arm / vgic / vgic-v3.c

diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index df1503650300767f774e711fcadf98037f60fcfd..9ae8adddff69ec24ef57557c732002ac0a3a6670 100644 (file)
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -234,6 +234,50 @@ void vgic_v3_enable(struct kvm_vcpu *vcpu)
        vgic_v3->vgic_hcr = ICH_HCR_EN;
 }
 
+int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq)
+{
+       struct kvm_vcpu *vcpu;
+       int byte_offset, bit_nr;
+       gpa_t pendbase, ptr;
+       bool status;
+       u8 val;
+       int ret;
+
+retry:
+       vcpu = irq->target_vcpu;
+       if (!vcpu)
+               return 0;
+
+       pendbase = GICR_PENDBASER_ADDRESS(vcpu->arch.vgic_cpu.pendbaser);
+
+       byte_offset = irq->intid / BITS_PER_BYTE;
+       bit_nr = irq->intid % BITS_PER_BYTE;
+       ptr = pendbase + byte_offset;
+
+       ret = kvm_read_guest(kvm, ptr, &val, 1);
+       if (ret)
+               return ret;
+
+       status = val & (1 << bit_nr);
+
+       spin_lock(&irq->irq_lock);
+       if (irq->target_vcpu != vcpu) {
+               spin_unlock(&irq->irq_lock);
+               goto retry;
+       }
+       irq->pending_latch = status;
+       vgic_queue_irq_unlock(vcpu->kvm, irq);
+
+       if (status) {
+               /* clear consumed data */
+               val &= ~(1 << bit_nr);
+               ret = kvm_write_guest(kvm, ptr, &val, 1);
+               if (ret)
+                       return ret;
+       }
+       return 0;
+}
+
 /* check for overlapping regions and for regions crossing the end of memory */
 static bool vgic_v3_check_base(struct kvm *kvm)
 {