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Date:   Wed, 3 Apr 2019 11:36:10 +0200
From:   Jan Kara <jack@suse.cz>
To:     Dave Chinner <david@fromorbit.com>
Cc:     Jan Kara <jack@suse.cz>, Kanchan Joshi <joshi.k@samsung.com>,
        linux-kernel@vger.kernel.org, linux-block@vger.kernel.org,
        linux-nvme@lists.infradead.org, linux-fsdevel@vger.kernel.org,
        linux-ext4@vger.kernel.org, axboe@fb.com, prakash.v@samsung.com,
        anshul@samsung.com, joshiiitr@gmail.com
Subject: Re: [PATCH v3 3/7] block: add write-hint to stream-id conversion
Message-ID: <20190403093610.GE8836@quack2.suse.cz>
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On Wed 03-04-19 07:35:08, Dave Chinner wrote:
> On Tue, Apr 02, 2019 at 11:20:44AM +0200, Jan Kara wrote:
> > On Mon 01-04-19 16:08:21, Dave Chinner wrote:
> > > On Fri, Mar 29, 2019 at 01:23:48PM +0530, Kanchan Joshi wrote:
> > > > +		if(streamid > nr_streams)
> > > > +			streamid = 0;
> > > 
> > > So, basically, we'll compress all the kernel hints down to "no hint"
> > > if there are more user streams than the device supports?
> > > 
> > > Surely we should be reserving a stream for the kernel hints separate
> > > from the user and "none" streams when we have limited device streams
> > > available...
> > 
> > The question is what to do in a situation when the device has exactly as
> > many hints as we currently offer to userspace.
> 
> Then do what we do now for that case. For every other case, the
> kernel should have reserved space and not get intermingled with
> userspace hints.

Yup, we are on the same page then.

								Honza
-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR