virtio_pci: split up vp_interrupt

This reorganizes virtio-pci code in vp_interrupt slightly, so that
it's easier to add per-vq MSI support on top.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 027f13f..951e673 100644 (file)
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -164,6 +164,37 @@ static void vp_notify(struct virtqueue *vq)
        iowrite16(info->queue_index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
 }
 
+/* Handle a configuration change: Tell driver if it wants to know. */
+static irqreturn_t vp_config_changed(int irq, void *opaque)
+{
+       struct virtio_pci_device *vp_dev = opaque;
+       struct virtio_driver *drv;
+       drv = container_of(vp_dev->vdev.dev.driver,
+                          struct virtio_driver, driver);
+
+       if (drv && drv->config_changed)
+               drv->config_changed(&vp_dev->vdev);
+       return IRQ_HANDLED;
+}
+
+/* Notify all virtqueues on an interrupt. */
+static irqreturn_t vp_vring_interrupt(int irq, void *opaque)
+{
+       struct virtio_pci_device *vp_dev = opaque;
+       struct virtio_pci_vq_info *info;
+       irqreturn_t ret = IRQ_NONE;
+       unsigned long flags;
+
+       spin_lock_irqsave(&vp_dev->lock, flags);
+       list_for_each_entry(info, &vp_dev->virtqueues, node) {
+               if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
+                       ret = IRQ_HANDLED;
+       }
+       spin_unlock_irqrestore(&vp_dev->lock, flags);
+
+       return ret;
+}
+
 /* A small wrapper to also acknowledge the interrupt when it's handled.
  * I really need an EIO hook for the vring so I can ack the interrupt once we
  * know that we'll be handling the IRQ but before we invoke the callback since
@@ -173,9 +204,6 @@ static void vp_notify(struct virtqueue *vq)
 static irqreturn_t vp_interrupt(int irq, void *opaque)
 {
        struct virtio_pci_device *vp_dev = opaque;
-       struct virtio_pci_vq_info *info;
-       irqreturn_t ret = IRQ_NONE;
-       unsigned long flags;
        u8 isr;
 
        /* reading the ISR has the effect of also clearing it so it's very
@@ -187,23 +215,10 @@ static irqreturn_t vp_interrupt(int irq, void *opaque)
                return IRQ_NONE;
 
        /* Configuration change?  Tell driver if it wants to know. */
-       if (isr & VIRTIO_PCI_ISR_CONFIG) {
-               struct virtio_driver *drv;
-               drv = container_of(vp_dev->vdev.dev.driver,
-                                  struct virtio_driver, driver);
-
-               if (drv && drv->config_changed)
-                       drv->config_changed(&vp_dev->vdev);
-       }
+       if (isr & VIRTIO_PCI_ISR_CONFIG)
+               vp_config_changed(irq, opaque);
 
-       spin_lock_irqsave(&vp_dev->lock, flags);
-       list_for_each_entry(info, &vp_dev->virtqueues, node) {
-               if (vring_interrupt(irq, info->vq) == IRQ_HANDLED)
-                       ret = IRQ_HANDLED;
-       }
-       spin_unlock_irqrestore(&vp_dev->lock, flags);
-
-       return ret;
+       return vp_vring_interrupt(irq, opaque);
 }
 
 /* the config->find_vq() implementation */