kfifo_dma_in_prepare (9)

kfifo_dma_in_prepare(fifo, sgl, nents, len);

fifo

address of the fifo to be used

sgl

pointer to the scatterlist array

nents

number of entries in the scatterlist array

len

number of elements to transfer

This macro fills a scatterlist for DMA input. It returns the number entries in the scatterlist array.

Note that with only one concurrent reader and one concurrent writer, you don't need extra locking to use these macros.