Re: [RFC PATCH 0/5] locks: implement "filp-private" (aka UNPOSIX)locks

[Volker Lendecke]

On Sat, Oct 12, 2013 at 11:12:03AM -0700, Frank Filz wrote:
> > This blog post of Jeremy's explains some of the history:
> > 
> > 
> > http://www.samba.org/samba/news/articles/low_point/tale_two_stds_os2
> > .html
> > 
> > See the section entitled "First Implementation Past the Post".
> 
> Interesting that Jeremy actually suggested the implementation should have
> had an arbitrary lock owner as part of the flock structure:
> 
> "This is an example of a POSIX interface not being future-proofed against
> modern techniques such as threading. A simple amendment to the original
> primitive allowing a user-defined "locking context" (like a process id) to
> be entered in the struct flock structure used to define the lock would have
> fixed this problem, along with extra flags allowing the number of locks per
> context to be recorded if needed."
> 
> But I'm happy with the lock context per kernel struct file as a solution,
> especially since that will allow locks to be sensibly passed to a forked
> process.
> 
> Another next step would be an asynchronous blocking lock...

Yes, please :-)

Volker

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