From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrzej Jakowski <andrzej.jakowski@linux.intel.com>
Subject: Re: [PATCH 1/2] block: introduce polling on bio level
Date: Fri, 31 Jan 2020 11:51:43 -0700
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To: Christoph Hellwig <hch@infradead.org>
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On 1/30/20 11:34 PM, Christoph Hellwig wrote:
> Can you explain this check?  This looks weird to me  I think we need
> a generalized check if a make_request based driver supports REQ_NOWAIT
> instead (and as a separate patch / patchset).

Original check used to reject polled IO for stackable block devices as 
"not supported". To solve that situation I introduced additional check 
to reject all non REQ_HIPRI requests. That check is not intended to 
generalize, like you indicated, but to conservatively select which 
requests to accept.
Perhaps there is better way to do that. Any suggestions?