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Date: Fri, 16 Oct 2009 10:49:24 +0200
From: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
To: Scott Wood <scottwood@freescale.com>
Subject: Re: [PATCH] hvc_console: returning 0 from put_chars is not an error
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On Thu, Oct 15, 2009 at 02:32:54PM -0500, Scott Wood wrote:
> Christian Borntraeger wrote:
>> About the backends, there are some that spin until the text is 
>> delivered (e.g. virtio) , others can drop (e.g. iucv is a connection 
>> oriented protocol and it will (and has to) drop if there is no 
>> connection). 
>
> Sure, dropping due to not having a connection makes sense.  That's  
> different from merely being busy.  Can the iucv code tell the difference  
> between those two states?

The states are handled by the hvc_iucv itself:
If the hvc_iucv code has a connection established, terminal or console data
are queued and sent to the peer. If the state is disconnected, terminal and
console data is discarded internally.

- Hendrik