XFILE_ALLOC
folio = xfile_get_folio(si->array->xfile, lo_pos, len, XFILE_ALLOC);
si->array->obj_size, XFILE_ALLOC);
if ((flags & XFILE_ALLOC) && pos + len > i_size_read(inode))
(flags & XFILE_ALLOC) ? SGP_CACHE : SGP_READ);
if (flags & XFILE_ALLOC)