Discontiguous memory and cacheflush

[Russell King - ARM Linux]

On Thu, Aug 16, 2012 at 09:27:26AM +0100, Dave Martin wrote:
> Could we use the currently must-be-zero flags parameter to add new
> functionality to this syscall, or are there legacy uses of that
> parameter (or history of userspace not bothering to zero it?)
> 
> For example, we could have something like
> 
> do_cache_op(struct iovec *iov, int iovcnt, CF_IOVEC)
> 
> to flush a discontiguous set of ranges described by an iovec (though we
> can of course also describe the ranges in other ways)

Why overload an existing syscall with multiple different argument types
rather than having a new syscall with a sane API?