flex_array: add flex_array_shrink function

		gfp_t flags);

int flex_array_clear(struct flex_array *fa, unsigned int element_nr);

void *flex_array_get(struct flex_array *fa, unsigned int element_nr);

int flex_array_shrink(struct flex_array *fa);

#endif /* _FLEX_ARRAY_H */

	}

	return &part->elements[index_inside_part(fa, element_nr)];

}

static int part_is_free(struct flex_array_part *part)

{

	int i;

	for (i = 0; i < sizeof(struct flex_array_part); i++)

		if (part->elements[i] != FLEX_ARRAY_FREE)

			return 0;

	return 1;

}

/**

 * flex_array_shrink - free unused second-level pages

 *

 * Frees all second-level pages that consist solely of unused

 * elements.  Returns the number of pages freed.

 *

 * Locking must be provided by the caller.

 */

int flex_array_shrink(struct flex_array *fa)

{

	struct flex_array_part *part;

	int max_part = nr_base_part_ptrs();

	int part_nr;

	int ret = 0;

	if (elements_fit_in_base(fa))

		return ret;

	for (part_nr = 0; part_nr < max_part; part_nr++) {

		part = fa->parts[part_nr];

		if (!part)

			continue;

		if (part_is_free(part)) {

			fa->parts[part_nr] = NULL;

			kfree(part);

			ret++;

		}

	}

	return ret;

}