KVM: Split up MSI-X assigned device IRQ handler

The threaded IRQ handler for MSI-X has almost nothing in common with the
INTx/MSI handler. Move its code into a dedicated handler.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 19 insertions, 13 deletions

diff --git a/virt/kvm/assigned-dev.c b/virt/kvm/assigned-dev.c
index 84ead5489650..7debe8c9e10e 100644
--- a/virt/kvm/assigned-dev.c
+++ b/virt/kvm/assigned-dev.c
@@ -58,8 +58,6 @@ static int find_index_from_host_irq(struct kvm_assigned_dev_kernel
 static irqreturn_t kvm_assigned_dev_thread(int irq, void *dev_id)
 {
         struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
-        u32 vector;
-        int index;
 
         if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_INTX) {
                 spin_lock(&assigned_dev->intx_lock);
@@ -68,20 +66,28 @@ static irqreturn_t kvm_assigned_dev_thread(int irq, void *dev_id)
                 spin_unlock(&assigned_dev->intx_lock);
         }
 
-        if (assigned_dev->irq_requested_type & KVM_DEV_IRQ_HOST_MSIX) {
-                index = find_index_from_host_irq(assigned_dev, irq);
-                if (index >= 0) {
-                        vector = assigned_dev->
-                                        guest_msix_entries[index].vector;
-                        kvm_set_irq(assigned_dev->kvm,
-                                    assigned_dev->irq_source_id, vector, 1);
-                }
-        } else
+        kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
+                    assigned_dev->guest_irq, 1);
+
+        return IRQ_HANDLED;
+}
+
+#ifdef __KVM_HAVE_MSIX
+static irqreturn_t kvm_assigned_dev_thread_msix(int irq, void *dev_id)
+{
+        struct kvm_assigned_dev_kernel *assigned_dev = dev_id;
+        int index = find_index_from_host_irq(assigned_dev, irq);
+        u32 vector;
+
+        if (index >= 0) {
+                vector = assigned_dev->guest_msix_entries[index].vector;
                 kvm_set_irq(assigned_dev->kvm, assigned_dev->irq_source_id,
-                            assigned_dev->guest_irq, 1);
+                            vector, 1);
+        }
 
         return IRQ_HANDLED;
 }
+#endif
 
 /* Ack the irq line for an assigned device */
 static void kvm_assigned_dev_ack_irq(struct kvm_irq_ack_notifier *kian)
@@ -279,7 +285,7 @@ static int assigned_device_enable_host_msix(struct kvm *kvm,
 
         for (i = 0; i < dev->entries_nr; i++) {
                 r = request_threaded_irq(dev->host_msix_entries[i].vector,
-                                         NULL, kvm_assigned_dev_thread,
+                                         NULL, kvm_assigned_dev_thread_msix,
                                          0, dev->irq_name, dev);
                 if (r)
                         goto err;