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Date:   Tue, 7 Jul 2020 17:00:14 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Kanchan Joshi <joshi.k@samsung.com>, Jens Axboe <axboe@kernel.dk>,
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        Selvakumar S <selvakuma.s1@samsung.com>,
        Nitesh Shetty <nj.shetty@samsung.com>,
        Javier Gonzalez <javier.gonz@samsung.com>
Subject: Re: [PATCH v3 4/4] io_uring: add support for zone-append
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On Tue, Jul 07, 2020 at 04:52:37PM +0100, Matthew Wilcox wrote:
> But userspace has to _do_ something with that information anyway.  So
> it must already have somewhere to put that information.
> 
> I do think that interpretation of that field should be a separate flag
> from WRITE_APPEND so apps which genuinely don't care about where the I/O
> ended up don't have to allocate some temporary storage.  eg a logging
> application which just needs to know that it managed to append to the
> end of the log and doesn't need to do anything if it's successful.

I agree with the concept of a flag for just returning the write
location.  Because if you don't need that O_APPEND is all you need
anyway.