Re: [PATCH v6 05/34] iov_iter: Change the direction macros into an enum

[David Howells]

Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote:

> > Change the ITER_SOURCE and ITER_DEST direction macros into an enum and
> > provide three new helper functions:
> > 
> >  iov_iter_dir() - returns the iterator direction
> >  iov_iter_is_dest() - returns true if it's an ITER_DEST iterator
> >  iov_iter_is_source() - returns true if it's an ITER_SOURCE iterator
> 
> What for?  We have two valid values -
> 	1) it is a data source
> 	2) it is not a data source
> Why do we need to store that as an enum?

Compile time type checking.

David