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Date:   Sun, 19 Jun 2022 03:25:27 +0100
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     linux-fsdevel@vger.kernel.org
Cc:     Christoph Hellwig <hch@lst.de>, Jens Axboe <axboe@kernel.dk>,
        Matthew Wilcox <willy@infradead.org>
Subject: Re: [PATCH 10/31] ITER_PIPE: fold data_start() and
 pipe_space_for_user() together
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On Sat, Jun 18, 2022 at 06:35:17AM +0100, Al Viro wrote:
> +	*npages = max(used - (int)pipe->max_usage, 0);

	*npages = max((int)pipe->max_usage - used, 0);

>  	if (off > 0 && off < PAGE_SIZE) { // anon and not full