+int image_set_limit(Image *i, uint64_t referenced_max) {
+ assert(i);
+
+ if (path_equal(i->path, "/") ||
+ path_startswith(i->path, "/usr"))
+ return -EROFS;
+
+ if (i->type != IMAGE_SUBVOLUME)
+ return -EOPNOTSUPP;
+
+ return btrfs_quota_limit(i->path, referenced_max);
+}
+
+int image_name_lock(const char *name, int operation, LockFile *ret) {
+ const char *p;
+
+ assert(name);
+ assert(ret);
+
+ /* Locks an image name, regardless of the precise path used. */
+
+ if (!image_name_is_valid(name))
+ return -EINVAL;
+
+ if (streq(name, ".host"))
+ return -EBUSY;
+
+ mkdir_p("/run/systemd/nspawn/locks", 0600);
+ p = strjoina("/run/systemd/nspawn/locks/name-", name);
+
+ return make_lock_file(p, operation, ret);
+}
+
+bool image_name_is_valid(const char *s) {
+ if (!filename_is_valid(s))
+ return false;
+
+ if (string_has_cc(s, NULL))
+ return false;
+
+ if (!utf8_is_valid(s))
+ return false;
+
+ /* Temporary files for atomically creating new files */
+ if (startswith(s, ".#"))
+ return false;
+
+ return true;
+}
+