static int select_pmem_id()

in namespace_devs.c [1885:1936]

• 41 lines of code
• 9 McCabe index (conditional complexity)

static int select_pmem_id(struct nd_region *nd_region, const uuid_t *pmem_id)
{
	int i;

	if (!pmem_id)
		return -ENODEV;

	for (i = 0; i < nd_region->ndr_mappings; i++) {
		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
		struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
		struct nd_namespace_label *nd_label = NULL;
		u64 hw_start, hw_end, pmem_start, pmem_end;
		struct nd_label_ent *label_ent;

		lockdep_assert_held(&nd_mapping->lock);
		list_for_each_entry(label_ent, &nd_mapping->labels, list) {
			nd_label = label_ent->label;
			if (!nd_label)
				continue;
			if (nsl_uuid_equal(ndd, nd_label, pmem_id))
				break;
			nd_label = NULL;
		}

		if (!nd_label) {
			WARN_ON(1);
			return -EINVAL;
		}

		/*
		 * Check that this label is compliant with the dpa
		 * range published in NFIT
		 */
		hw_start = nd_mapping->start;
		hw_end = hw_start + nd_mapping->size;
		pmem_start = nsl_get_dpa(ndd, nd_label);
		pmem_end = pmem_start + nsl_get_rawsize(ndd, nd_label);
		if (pmem_start >= hw_start && pmem_start < hw_end
				&& pmem_end <= hw_end && pmem_end > hw_start)
			/* pass */;
		else {
			dev_dbg(&nd_region->dev, "%s invalid label for %pUb\n",
				dev_name(ndd->dev),
				nsl_uuid_raw(ndd, nd_label));
			return -EINVAL;
		}

		/* move recently validated label to the front of the list */
		list_move(&label_ent->list, &nd_mapping->labels);
	}
	return 0;
}