We don't support large entries which expand two more level xa_node in split. For case "xas->xa_shift + 2 * XA_CHUNK_SHIFT == order", we also need two level of xa_node to expand. Distinguish entry as large entry in case "xas->xa_shift + 2 * XA_CHUNK_SHIFT == order". As max order of folio in pagecache (MAX_PAGECACHE_ORDER) is <= (XA_CHUNK_SHIFT * 2 - 1), this change is more likely a cleanup... Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> --- lib/xarray.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/xarray.c b/lib/xarray.c index d0732c5b8403..3fac3f2cea9d 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -1022,7 +1022,7 @@ void xas_split_alloc(struct xa_state *xas, void *entry, unsigned int order, unsigned int mask = xas->xa_sibs; /* XXX: no support for splitting really large entries yet */ - if (WARN_ON(xas->xa_shift + 2 * XA_CHUNK_SHIFT < order)) + if (WARN_ON(xas->xa_shift + 2 * XA_CHUNK_SHIFT <= order)) goto nomem; if (xas->xa_shift + XA_CHUNK_SHIFT > order) return; -- 2.30.0