Function range_tree_remove_impl

freebsd/contrib/openzfs/module/zfs/range_tree.c:427–540

}

static void
range_tree_remove_impl(range_tree_t *rt, uint64_t start, uint64_t size,
    boolean_t do_fill)
{
	zfs_btree_index_t where;
	range_seg_t *rs;
	range_seg_max_t rsearch, rs_tmp;
	uint64_t end = start + size;
	boolean_t left_over, right_over;

	VERIFY3U(size, !=, 0);
	VERIFY3U(size, <=, rt->rt_space);
	if (rt->rt_type == RANGE_SEG64)
		ASSERT3U(start + size, >, start);

	rs_set_start(&rsearch, rt, start);
	rs_set_end(&rsearch, rt, end);
	rs = zfs_btree_find(&rt->rt_root, &rsearch, &where);

	/* Make sure we completely overlap with someone */
	if (rs == NULL) {
		zfs_panic_recover("zfs: removing nonexistent segment from "
		    "range tree (offset=%llx size=%llx)",
		    (longlong_t)start, (longlong_t)size);
		return;
	}

	/*
	 * Range trees with gap support must only remove complete segments
	 * from the tree. This allows us to maintain accurate fill accounting
	 * and to ensure that bridged sections are not leaked. If we need to
	 * remove less than the full segment, we can only adjust the fill count.
	 */
	if (rt->rt_gap != 0) {
		if (do_fill) {
			if (rs_get_fill(rs, rt) == size) {
				start = rs_get_start(rs, rt);
				end = rs_get_end(rs, rt);
				size = end - start;
			} else {
				range_tree_adjust_fill(rt, rs, -size);
				return;
			}
		} else if (rs_get_start(rs, rt) != start ||
		    rs_get_end(rs, rt) != end) {
			zfs_panic_recover("zfs: freeing partial segment of "
			    "gap tree (offset=%llx size=%llx) of "
			    "(offset=%llx size=%llx)",
			    (longlong_t)start, (longlong_t)size,
			    (longlong_t)rs_get_start(rs, rt),
			    (longlong_t)rs_get_end(rs, rt) - rs_get_start(rs,
			    rt));
			return;
		}
	}

	VERIFY3U(rs_get_start(rs, rt), <=, start);
	VERIFY3U(rs_get_end(rs, rt), >=, end);