From mboxrd@z Thu Jan  1 00:00:00 1970
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
Date: Thu, 16 Aug 2012 10:19:53 +0100
Subject: Discontiguous memory and cacheflush
In-Reply-To: <20120816082726.GA2101@linaro.org>
References: <20120813160008.GA30302@n2100.arm.linux.org.uk>
 <1822556972.575011.1345068509111.JavaMail.root@mozilla.com>
 <20120816082726.GA2101@linaro.org>
Message-ID: <20120816091953.GL18957@n2100.arm.linux.org.uk>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

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?