KFIFO_DMA_OUT_PREPAR(9) FIFO Buffer KFIFO_DMA_OUT_PREPAR(9)
NAME
kfifo_dma_out_prepare - setup a scatterlist for DMA output
SYNOPSIS
kfifo_dma_out_prepare(fifo, sgl, nents, len);
ARGUMENTS
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
DESCRIPTION
This macro fills a scatterlist for DMA output which at most len bytes to transfer. It returns the number entries in the scatterlist array.
A zero means there is no space available and the scatterlist is not filled.
Note that with only one concurrent reader and one concurrent writer, you don't need extra locking to use these macros.
COPYRIGHT
Kernel Hackers Manual 3.10 June 2014 KFIFO_DMA_OUT_PREPAR(9)
