From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tim Deegan <tim@xen.org>
Subject: Re: [PATCH 5/5] xen: Add V4V implementation
Date: Thu, 9 Aug 2012 11:38:40 +0100
Message-ID: <20120809103840.GD16986@ocelot.phlegethon.org>
References: <1344023454-31425-1-git-send-email-jean.guyader@citrix.com>
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To: Jean Guyader <jean.guyader@citrix.com>
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Hi,

This looks pretty good; I think you've addressed almost all my comments
except for one, which is really a design decision raether than an
implementation one.  As I said last time: 

] And what about protocol?  Protocol seems to have ended up as a bit of a
] second-class citizen in v4v; it's defined, and indeed required, but not
] used for routing or for acccess control, so all traffic to a given port
] _on every protocol_ ends up on the same ring. 
] 
] This is the inverse of the TCP/IP namespace that you're copying, where
] protocol demux happens before port demux.  And I think it will bite
] someone if you ever, for example, want to send ICMP or GRE over a v4v
] channel.

I see Jan has some comments on the detail; all I have to add is this:

At 20:50 +0100 on 03 Aug (1344027054), Jean Guyader wrote:
> +
> +
> +struct list_head viprules = LIST_HEAD_INIT(viprules);
> +static DEFINE_RWLOCK(viprules_lock);

Please add comments describing this lock and where it comes in the
locking order relative to the locks below -- it looks like it's always
taken after any other locks but please make it clear.

> +/*
> + * Structure definitions
> + */
> +
> +#define V4V_RING_MAGIC          0xA822f72bb0b9d8cc
> +#define V4V_RING_DATA_MAGIC	0x45fe852220b801d4

Thanks for getting rid of the #ifdefs here, but you need to keep the
'ULL' suffix so this will compile properly on 32-bit.

Cheers,

Tim.