virtio_ring: change host notification API
Currently a host kick error is silently ignored and not reflected in
the virtqueue of a particular virtio device.
Changing the notify API for guest->host notification seems to be one
prerequisite in order to be able to handle such errors in the context
where the kick is triggered.
This patch changes the notify API. The notify function must return a
bool return value. It returns false if the host notification failed.
Signed-off-by: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
index 1ba0d68..e9fdeb8 100644
--- a/drivers/virtio/virtio_mmio.c
+++ b/drivers/virtio/virtio_mmio.c
@@ -219,13 +219,14 @@
/* Transport interface */
/* the notify function used when creating a virt queue */
-static void vm_notify(struct virtqueue *vq)
+static bool vm_notify(struct virtqueue *vq)
{
struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vq->vdev);
/* We write the queue's selector into the notification register to
* signal the other end */
writel(vq->index, vm_dev->base + VIRTIO_MMIO_QUEUE_NOTIFY);
+ return true;
}
/* Notify all virtqueues on an interrupt. */
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 98917fc..a37c699 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -197,13 +197,14 @@
}
/* the notify function used when creating a virt queue */
-static void vp_notify(struct virtqueue *vq)
+static bool vp_notify(struct virtqueue *vq)
{
struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
/* we write the queue's selector into the notification register to
* signal the other end */
iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
+ return true;
}
/* Handle a configuration change: Tell driver if it wants to know. */
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 6547d46..97dd516 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -81,7 +81,7 @@
u16 last_used_idx;
/* How to notify other side. FIXME: commonalize hcalls! */
- void (*notify)(struct virtqueue *vq);
+ bool (*notify)(struct virtqueue *vq);
#ifdef DEBUG
/* They're supposed to lock for us. */
@@ -744,7 +744,7 @@
struct virtio_device *vdev,
bool weak_barriers,
void *pages,
- void (*notify)(struct virtqueue *),
+ bool (*notify)(struct virtqueue *),
void (*callback)(struct virtqueue *),
const char *name)
{