CONFIG_LEGACY_DIRECT_IO (not configurable)

modulename: direct-io.ko

configname: CONFIG_LEGACY_DIRECT_IO

Linux Kernel Configuration
└─>File systems
└─>LEGACY_DIRECT_IO
In linux kernel since version 4.14.326 (release Date: 2023-09-23)  
source code:

is depended by
CONFIG_EXT2_FS