Subject: Re: [RFC PATCH] net: add dataref destructor to sk_buff

From: Gregory Haskins <[email-masked]>
Date: Fri, 13 Nov 2009 20:33:35 -0500

Herbert Xu wrote:
> On Tue, Nov 10, 2009 at 10:45:16AM -0500, Gregory Haskins wrote:
>> What I am getting at is as follows:  From a real basic perspective, you
>> can look at all of this as a simple synchronous call (i.e. sendmsg()).
>> The "app" (be it a userspace app, or a guest) prepares a buffer for
>> transmission, and offers it to the next layer in the stack.  The app
>> must maintain the integrity of that buffer at least until the layer
>> below it signifies that it is "consumed".  This may mean its a
>> synchronous call, like sendmsg(), or it may be asynchronous, like AIO.
> 
> Neither sendmsg() nor sendfile() is synchronous in the way you
> imagine.

Well, not with respect to the overall protocol, of course not.  But with
respect to the buffer in question, it _has_ to be.  Or am I missing
something?

Kind Regards,
-Greg