Function intr_map_irq

freebsd/kern/subr_intr.c:1662–1689

* Allocate and fill new entry in irq_map table. */

 * Allocate and fill new entry in irq_map table.
 */
u_int
intr_map_irq(device_t dev, intptr_t xref, struct intr_map_data *data)
{
	u_int i;
	struct intr_map_entry *entry;

	/* Prepare new entry first. */
	entry = malloc(sizeof(*entry), M_INTRNG, M_WAITOK | M_ZERO);

	entry->dev = dev;
	entry->xref = xref;
	entry->map_data = data;
	entry->isrc = NULL;

	mtx_lock(&irq_map_lock);
	for (i = irq_map_first_free_idx; i < irq_map_count; i++) {
		if (irq_map[i] == NULL) {
			irq_map[i] = entry;
			irq_map_first_free_idx = i + 1;
			mtx_unlock(&irq_map_lock);
			return (i);
		}
	}
	mtx_unlock(&irq_map_lock);

	/* XXX Expand irq_map table */
	panic("IRQ mapping table is full.");
}

/*
 * Remove and free mapping entry.