Function intr_alloc_msi

freebsd/kern/subr_intr.c:1322–1368

}

int
intr_alloc_msi(device_t pci, device_t child, intptr_t xref, int count,
    int maxcount, int *irqs)
{
	struct iommu_domain *domain;
	struct intr_irqsrc **isrc;
	struct intr_pic *pic;
	device_t pdev;
	struct intr_map_data_msi *msi;
	int err, i;

	pic = pic_lookup(NULL, xref, FLAG_MSI);
	if (pic == NULL)
		return (ESRCH);

	KASSERT((pic->pic_flags & FLAG_TYPE_MASK) == FLAG_MSI,
	    ("%s: Found a non-MSI controller: %s", __func__,
	     device_get_name(pic->pic_dev)));

	/*
	 * If this is the first time we have used this context ask the
	 * interrupt controller to map memory the msi source will need.
	 */
	err = MSI_IOMMU_INIT(pic->pic_dev, child, &domain);
	if (err != 0)
		return (err);

	isrc = malloc(sizeof(*isrc) * count, M_INTRNG, M_WAITOK);
	err = MSI_ALLOC_MSI(pic->pic_dev, child, count, maxcount, &pdev, isrc);
	if (err != 0) {
		free(isrc, M_INTRNG);
		return (err);
	}

	for (i = 0; i < count; i++) {
		isrc[i]->isrc_iommu = domain;
		msi = (struct intr_map_data_msi *)intr_alloc_map_data(
		    INTR_MAP_DATA_MSI, sizeof(*msi), M_WAITOK | M_ZERO);
		msi-> isrc = isrc[i];

		irqs[i] = intr_map_irq(pic->pic_dev, xref,
		    (struct intr_map_data *)msi);
	}
	free(isrc, M_INTRNG);

	return (err);
}

int
intr_release_msi(device_t pci, device_t child, intptr_t xref, int count,