bitmap_parse_user(9) centos man page | unix.com

BITMAP_PARSE_USER(9)					  Basic Kernel Library Functions				      BITMAP_PARSE_USER(9)

NAME
       bitmap_parse_user - convert an ASCII hex string in a user buffer into a bitmap

SYNOPSIS
       int bitmap_parse_user(const char __user * ubuf, unsigned int ulen, unsigned long * maskp, int nmaskbits);

ARGUMENTS
       ubuf
	   pointer to user buffer containing string.

       ulen
	   buffer size in bytes. If string is smaller than this then it must be terminated with a .

       maskp
	   pointer to bitmap array that will contain result.

       nmaskbits
	   size of bitmap, in bits.

DESCRIPTION
       Wrapper for __bitmap_parse, providing it with user buffer.

       We cannot have this as an inline function in bitmap.h because it needs linux/uaccess.h to get the access_ok declaration and this causes
       cyclic dependencies.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014						      BITMAP_PARSE_USER(9)