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Date:   Tue, 20 Jun 2023 06:29:35 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Jens Axboe <axboe@kernel.dk>
Cc:     Christoph Hellwig <hch@infradead.org>, io-uring@vger.kernel.org,
        linux-block@vger.kernel.org
Subject: Re: [PATCH 2/3] block: mark bdev files as FMODE_NOWAIT if underlying
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On Tue, Jun 20, 2023 at 07:24:56AM -0600, Jens Axboe wrote:
> I think we need stronger justification than that, it's much nicer to
> have it in the open path than doing the same check over and over for
> each IO.
> 
> With your new proposed scheme, why can't the check and FMODE_NOWAIT set
> still be in open?

Because I want to move the by now huge number of static flags out of
file->f_mode and into file->f_op.flags.  It's just that with this patch
this one flag isn't static anymore for block devices.  We could also
do two sets of file operations assuming we never allow run-time changes
for QUEUE_FLAG_NOWAIT.  If we care about optimizing fo async I/O on the
few drivers not supporting QUEUE_FLAG_NOWAIT that's probably the next
best thing.