static int
vtpci_alloc_interrupts(struct vtpci_softc *sc, int flags, int nvqs,
struct vq_alloc_info *vq_info)
{
int i, nvectors, error;
/*
* Only allocate a vector for virtqueues that are actually
* expecting an interrupt.
*/
for (nvectors = 0, i = 0; i < nvqs; i++)
if (vq_info[i].vqai_intr != NULL)
nvectors++;
if (vtpci_disable_msix != 0 ||
sc->vtpci_flags & VIRTIO_PCI_FLAG_NO_MSIX ||
flags & VIRTIO_ALLOC_VQS_DISABLE_MSIX ||
vtpci_alloc_msix(sc, nvectors) != 0) {
/*
* Use MSI interrupts if available. Otherwise, we fallback
* to legacy interrupts.
*/
if ((sc->vtpci_flags & VIRTIO_PCI_FLAG_NO_MSI) == 0 &&
vtpci_alloc_msi(sc) == 0)
sc->vtpci_flags |= VIRTIO_PCI_FLAG_MSI;
sc->vtpci_nintr_res = 1;
}
error = vtpci_alloc_intr_resources(sc, nvqs, vq_info);
return (error);
}
static int
vtpci_alloc_intr_msix_shared(struct vtpci_softc *sc)
{
int error;
if (vtpci_disable_msix != 0 ||
sc->vtpci_flags & VTPCI_FLAG_NO_MSIX)
return (ENOTSUP);
error = vtpci_alloc_msix(sc, 1);
if (error)
return (error);
sc->vtpci_flags |= VTPCI_FLAG_MSIX | VTPCI_FLAG_SHARED_MSIX;
return (0);
}
static int
vtpci_alloc_intr_msix_pervq(struct vtpci_softc *sc)
{
int i, nvectors, error;
if (vtpci_disable_msix != 0 ||
sc->vtpci_flags & VTPCI_FLAG_NO_MSIX)
return (ENOTSUP);
for (nvectors = 0, i = 0; i < sc->vtpci_nvqs; i++) {
if (sc->vtpci_vqs[i].vtv_no_intr == 0)
nvectors++;
}
error = vtpci_alloc_msix(sc, nvectors);
if (error)
return (error);
sc->vtpci_flags |= VTPCI_FLAG_MSIX;
return (0);
}
