在 2021/4/8 下午5:38, Cindy Lu 写道:
Add support for configure interrupt, use kvm_irqfd_assign and set the
gsi to kernel. When the configure notifier was eventfd_signal by host
kernel, this will finally inject an msix interrupt to guest
Signed-off-by: Cindy Lu <l...@redhat.com>
---
hw/virtio/virtio-pci.c | 91 ++++++++++++++++++++++++++++++++++++++++--
1 file changed, 88 insertions(+), 3 deletions(-)
diff --git a/hw/virtio/virtio-pci.c b/hw/virtio/virtio-pci.c
index 481f6e7505..7b02f42c06 100644
--- a/hw/virtio/virtio-pci.c
+++ b/hw/virtio/virtio-pci.c
@@ -664,7 +664,6 @@ static uint32_t virtio_read_config(PCIDevice *pci_dev,
}
static int kvm_virtio_pci_vq_vector_use(VirtIOPCIProxy *proxy,
- unsigned int queue_no,
unsigned int vector)
{
VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector];
@@ -726,7 +725,7 @@ static int kvm_virtio_pci_vector_use(VirtIOPCIProxy *proxy,
int nvqs)
if (vector >= msix_nr_vectors_allocated(dev)) {
continue;
}
- ret = kvm_virtio_pci_vq_vector_use(proxy, queue_no, vector);
+ ret = kvm_virtio_pci_vq_vector_use(proxy, vector);
if (ret < 0) {
goto undo;
}
@@ -760,6 +759,56 @@ undo:
}
return ret;
}
+static int kvm_virtio_pci_vector_config_use(VirtIOPCIProxy *proxy)
+{
+ VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
+ unsigned int vector;
+ int ret;
+ EventNotifier *n = virtio_get_config_notifier(vdev);
+ vector = vdev->config_vector ;
+ ret = kvm_virtio_pci_vq_vector_use(proxy, vector);
+ if (ret < 0) {
+ goto undo;
+ }
+ ret = kvm_virtio_pci_irqfd_use(proxy, n, vector);
So the kvm_virtio_pci_vector_use() has the following codes:
/* If guest supports masking, set up irqfd now.
* Otherwise, delay until unmasked in the frontend.
*/
if (vdev->use_guest_notifier_mask && k->guest_notifier_mask) {
vq = virtio_get_queue(vdev, queue_no);
n = virtio_queue_get_guest_notifier(vq);
ret = kvm_virtio_pci_irqfd_use(proxy, n, vector);
if (ret < 0) {
kvm_virtio_pci_vq_vector_release(proxy, vector);
goto undo;
}
}
Do we need to check the masking support here as well?
Btw, I think we can factor out the core logic (decouple the queue_no) of
kvm_virtio_pci_vector_user() and let it be reused by config interrupt.
+ if (ret < 0) {
+ goto undo;
+ }
+ return 0;
+undo:
+ kvm_virtio_pci_irqfd_release(proxy, n, vector);
+ return ret;
+}
+static void kvm_virtio_pci_vector_config_release(VirtIOPCIProxy *proxy)
+{
+ PCIDevice *dev = &proxy->pci_dev;
+ VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
+ unsigned int vector;
+ EventNotifier *n = virtio_get_config_notifier(vdev);
+ vector = vdev->config_vector ;
+ if (vector >= msix_nr_vectors_allocated(dev)) {
+ return;
+ }
+ kvm_virtio_pci_irqfd_release(proxy, n, vector);
+ kvm_virtio_pci_vq_vector_release(proxy, vector);
+}
+static int virtio_pci_set_config_notifier(DeviceState *d, bool assign)
+{
+ VirtIOPCIProxy *proxy = to_virtio_pci_proxy(d);
+ VirtIODevice *vdev = virtio_bus_get_device(&proxy->bus);
+ EventNotifier *notifier = virtio_get_config_notifier(vdev);
+ int r = 0;
+ if (assign) {
+ r = event_notifier_init(notifier, 0);
+ virtio_set_config_notifier_fd_handler(vdev, true, true);
+ kvm_virtio_pci_vector_config_use(proxy);
+ } else {
+ virtio_set_config_notifier_fd_handler(vdev, false, true);
So let's try to unify the codes between this and
virtio_queue_set_guest_notifier_fd_handler(). Bascailly it's just
decouple virtqueue *.
+ kvm_virtio_pci_vector_config_release(proxy);
+ event_notifier_cleanup(notifier);
+ }
+ return r;
+}
static void kvm_virtio_pci_vector_release(VirtIOPCIProxy *proxy, int nvqs)
{
@@ -858,6 +907,14 @@ static int virtio_pci_vector_unmask(PCIDevice *dev,
unsigned vector,
EventNotifier *n;
int ret, index, unmasked = 0;
+ if (vdev->use_config_notifier == true) {
+ n = virtio_get_config_notifier(vdev);
+ ret = virtio_pci_vq_vector_unmask(proxy, 0, vector, msg,
+ VIRTIO_CONFIG_VECTOR, n);
+ if (ret < 0) {
+ goto config_undo;
+ }
+ }
while (vq) {
index = virtio_get_queue_index(vq);
if (!virtio_queue_get_num(vdev, index)) {
@@ -889,6 +946,10 @@ undo:
}
vq = virtio_vector_next_queue(vq);
}
+ config_undo:
+ n = virtio_get_config_notifier(vdev);
+ virtio_pci_vq_vector_mask(proxy, 0, vector,
+ VIRTIO_CONFIG_VECTOR, n);
return ret;
}
@@ -900,6 +961,10 @@ static void virtio_pci_vector_mask(PCIDevice *dev, unsigned vector)
EventNotifier *n;
int index;
+ if (vdev->use_config_notifier == true) {
Is this sufficient to know the vector is used by config interrupt?
+ n = virtio_get_config_notifier(vdev);
+ virtio_pci_vq_vector_mask(proxy, 0, vector, VIRTIO_CONFIG_VECTOR, n);
+ }
while (vq) {
index = virtio_get_queue_index(vq);
n = virtio_queue_get_guest_notifier(vq);
@@ -945,6 +1010,21 @@ static void virtio_pci_vector_poll(PCIDevice *dev,
msix_set_pending(dev, vector);
}
}
+ if (vdev->use_config_notifier == true) {
+ vector = vdev->config_vector;
+ notifier = virtio_get_config_notifier(vdev);
+ if (vector < vector_start || vector >= vector_end ||
+ !msix_is_masked(dev, vector)) {
+ return;
+ }
+ if (k->guest_notifier_pending) {
+ if (k->guest_notifier_pending(vdev, 0, VIRTIO_CONFIG_VECTOR)) {
+ msix_set_pending(dev, vector);
+ }
+ } else if (event_notifier_test_and_clear(notifier)) {
+ msix_set_pending(dev, vector);
+ }
+ }
Let's unify the code here with the code that deal with vq vectors in the
loop above.
Thanks
}
static int virtio_pci_set_guest_notifier(DeviceState *d, int n, bool assign,
@@ -1032,6 +1112,10 @@ static int virtio_pci_set_guest_notifiers(DeviceState
*d, int nvqs, bool assign)
goto assign_error;
}
}
+ r = virtio_pci_set_config_notifier(d, assign);
+ if (r < 0) {
+ goto config_error;
+ }
r = msix_set_vector_notifiers(&proxy->pci_dev,
virtio_pci_vector_unmask,
virtio_pci_vector_mask,
@@ -1048,7 +1132,8 @@ notifiers_error:
assert(assign);
kvm_virtio_pci_vector_release(proxy, nvqs);
}
-
+ config_error:
+ kvm_virtio_pci_vector_config_release(proxy);
assign_error:
/* We get here on assignment failure. Recover by undoing for VQs 0 .. n.
*/
assert(assign);