centos man page for kfifo_from_user

KFIFO_FROM_USER(9)						    FIFO Buffer 						KFIFO_FROM_USER(9)

NAME
       kfifo_from_user - puts some data from user space into the fifo

SYNOPSIS
       kfifo_from_user(fifo, from, len, copied);

ARGUMENTS
       fifo
	   address of the fifo to be used

       from
	   pointer to the data to be added

       len
	   the length of the data to be added

       copied
	   pointer to output variable to store the number of copied bytes

DESCRIPTION
       This macro copies at most len bytes from the from into the fifo, depending of the available space and returns -EFAULT/0.

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

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014							KFIFO_FROM_USER(9)