static int dev_dax_shrink()

in bus.c [896:934]

• 35 lines of code
• 8 McCabe index (conditional complexity)

static int dev_dax_shrink(struct dev_dax *dev_dax, resource_size_t size)
{
	resource_size_t to_shrink = dev_dax_size(dev_dax) - size;
	struct dax_region *dax_region = dev_dax->region;
	struct device *dev = &dev_dax->dev;
	int i;

	for (i = dev_dax->nr_range - 1; i >= 0; i--) {
		struct range *range = &dev_dax->ranges[i].range;
		struct dax_mapping *mapping = dev_dax->ranges[i].mapping;
		struct resource *adjust = NULL, *res;
		resource_size_t shrink;

		shrink = min_t(u64, to_shrink, range_len(range));
		if (shrink >= range_len(range)) {
			devm_release_action(dax_region->dev,
					unregister_dax_mapping, &mapping->dev);
			trim_dev_dax_range(dev_dax);
			to_shrink -= shrink;
			if (!to_shrink)
				break;
			continue;
		}

		for_each_dax_region_resource(dax_region, res)
			if (strcmp(res->name, dev_name(dev)) == 0
					&& res->start == range->start) {
				adjust = res;
				break;
			}

		if (dev_WARN_ONCE(dev, !adjust || i != dev_dax->nr_range - 1,
					"failed to find matching resource\n"))
			return -ENXIO;
		return adjust_dev_dax_range(dev_dax, adjust, range_len(range)
				- shrink);
	}
	return 0;
}