window_free 2928 fs/btrfs/free-space-cache.c u64 window_free; window_free 2949 fs/btrfs/free-space-cache.c window_free = entry->bytes; window_free 2968 fs/btrfs/free-space-cache.c window_free += entry->bytes; window_free 2973 fs/btrfs/free-space-cache.c if (window_free < bytes || max_extent < cont1_bytes)