CONFIG_HAVE_GENERIC_DMA_COHERENT (not configurable)

modulename: coherent.ko

configname: CONFIG_HAVE_GENERIC_DMA_COHERENT

Linux Kernel Configuration
└─>Library routines
└─>HAVE_GENERIC_DMA_COHERENT
In linux kernel since version 3.10 (release Date: 2013-06-30)  
source code:
kernel/dma/coherent.c