Function resource_list_reserve

freebsd/kern/subr_bus.c:3351–3373

* @brief Allocate a reserved resource * * This can be used by buses to force the allocation of resources * that are always active in the system even if they are not allocated * by a driver (e.g. PCI BARs). This function is usually called when * adding a new child to the bus. The resource is allocated from the * parent bus when it is reserved. The resource list entry is marked * with RLE_

 *			resource could be allocated
 */
struct resource *
resource_list_reserve(struct resource_list *rl, device_t bus, device_t child,
    int type, int *rid, rman_res_t start, rman_res_t end, rman_res_t count, u_int flags)
{
	struct resource_list_entry *rle = NULL;
	int passthrough = (device_get_parent(child) != bus);
	struct resource *r;

	if (passthrough)
		panic(
    "resource_list_reserve() should only be called for direct children");
	if (flags & RF_ACTIVE)
		panic(
    "resource_list_reserve() should only reserve inactive resources");

	r = resource_list_alloc(rl, bus, child, type, rid, start, end, count,
	    flags);
	if (r != NULL) {
		rle = resource_list_find(rl, type, *rid);
		rle->flags |= RLE_RESERVED;
	}
	return (r);
}

/**
 * @brief Helper function for implementing BUS_ALLOC_RESOURCE()