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path: root/drivers/s390/kvm/kvm_virtio.c
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Diffstat (limited to 'drivers/s390/kvm/kvm_virtio.c')
-rw-r--r--drivers/s390/kvm/kvm_virtio.c66
1 files changed, 60 insertions, 6 deletions
diff --git a/drivers/s390/kvm/kvm_virtio.c b/drivers/s390/kvm/kvm_virtio.c
index 4e298bc8949d..5a46b8c5d68a 100644
--- a/drivers/s390/kvm/kvm_virtio.c
+++ b/drivers/s390/kvm/kvm_virtio.c
@@ -32,6 +32,7 @@
* The pointer to our (page) of device descriptions.
*/
static void *kvm_devices;
+struct work_struct hotplug_work;
struct kvm_device {
struct virtio_device vdev;
@@ -328,13 +329,54 @@ static void scan_devices(void)
}
/*
+ * match for a kvm device with a specific desc pointer
+ */
+static int match_desc(struct device *dev, void *data)
+{
+ if ((ulong)to_kvmdev(dev_to_virtio(dev))->desc == (ulong)data)
+ return 1;
+
+ return 0;
+}
+
+/*
+ * hotplug_device tries to find changes in the device page.
+ */
+static void hotplug_devices(struct work_struct *dummy)
+{
+ unsigned int i;
+ struct kvm_device_desc *d;
+ struct device *dev;
+
+ for (i = 0; i < PAGE_SIZE; i += desc_size(d)) {
+ d = kvm_devices + i;
+
+ /* end of list */
+ if (d->type == 0)
+ break;
+
+ /* device already exists */
+ dev = device_find_child(kvm_root, d, match_desc);
+ if (dev) {
+ /* XXX check for hotplug remove */
+ put_device(dev);
+ continue;
+ }
+
+ /* new device */
+ printk(KERN_INFO "Adding new virtio device %p\n", d);
+ add_kvm_device(d, i);
+ }
+}
+
+/*
* we emulate the request_irq behaviour on top of s390 extints
*/
static void kvm_extint_handler(u16 code)
{
struct virtqueue *vq;
u16 subcode;
- int config_changed;
+ u32 param;
subcode = S390_lowcore.cpu_addr;
if ((subcode & 0xff00) != VIRTIO_SUBCODE_64)
@@ -343,18 +385,28 @@ static void kvm_extint_handler(u16 code)
/* The LSB might be overloaded, we have to mask it */
vq = (struct virtqueue *)(S390_lowcore.ext_params2 & ~1UL);
- /* We use the LSB of extparam, to decide, if this interrupt is a config
- * change or a "standard" interrupt */
- config_changed = S390_lowcore.ext_params & 1;
+ /* We use ext_params to decide what this interrupt means */
+ param = S390_lowcore.ext_params & VIRTIO_PARAM_MASK;
- if (config_changed) {
+ switch (param) {
+ case VIRTIO_PARAM_CONFIG_CHANGED:
+ {
struct virtio_driver *drv;
drv = container_of(vq->vdev->dev.driver,
struct virtio_driver, driver);
if (drv->config_changed)
drv->config_changed(vq->vdev);
- } else
+
+ break;
+ }
+ case VIRTIO_PARAM_DEV_ADD:
+ schedule_work(&hotplug_work);
+ break;
+ case VIRTIO_PARAM_VRING_INTERRUPT:
+ default:
vring_interrupt(0, vq);
+ break;
+ }
}
/*
@@ -383,6 +435,8 @@ static int __init kvm_devices_init(void)
kvm_devices = (void *) real_memory_size;
+ INIT_WORK(&hotplug_work, hotplug_devices);
+
ctl_set_bit(0, 9);
register_external_interrupt(0x2603, kvm_extint_handler);