[PATCH V2 2/2] vDPA/ifcvf: implement doorbell mapping for ifcvf
From: Zhu Lingshan <hidden>
Date: 2021-05-14 10:04:50
Also in:
kvm
Subsystem:
intel virtio data path accelerator, the rest, virtio core · Maintainers:
Zhu Lingshan, Linus Torvalds, "Michael S. Tsirkin", Jason Wang
This commit implements doorbell mapping feature for ifcvf. This feature maps the notify page to userspace, to eliminate vmexit when kick a vq. Signed-off-by: Zhu Lingshan <redacted> --- drivers/vdpa/ifcvf/ifcvf_main.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index ab0ab5cf0f6e..41c09437602d 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c@@ -413,6 +413,21 @@ static int ifcvf_vdpa_get_vq_irq(struct vdpa_device *vdpa_dev, return vf->vring[qid].irq; } +static struct vdpa_notification_area ifcvf_get_vq_notification(struct vdpa_device *vdpa_dev, + u16 idx) +{ + struct ifcvf_adapter *adapter = vdpa_to_adapter(vdpa_dev); + struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev); + struct pci_dev *pdev = adapter->pdev; + struct vdpa_notification_area area; + + area.addr = vf->vring[idx].notify_pa; + area.size = PAGE_SIZE; + if (area.addr % PAGE_SIZE) + IFCVF_DBG(pdev, "vq %u doorbell address is not PAGE_SIZE aligned\n", idx); + return area; +} + /* * IFCVF currently does't have on-chip IOMMU, so not * implemented set_map()/dma_map()/dma_unmap()
@@ -440,6 +455,7 @@ static const struct vdpa_config_ops ifc_vdpa_ops = { .get_config = ifcvf_vdpa_get_config, .set_config = ifcvf_vdpa_set_config, .set_config_cb = ifcvf_vdpa_set_config_cb, + .get_vq_notification = ifcvf_get_vq_notification, }; static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
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2.27.0