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Date:   Sun, 19 Jun 2022 05:01:29 +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 30/31] pipe_get_pages(): switch to append_pipe()
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On Sat, Jun 18, 2022 at 06:35:37AM +0100, Al Viro wrote:

>  		get_page(*p++ = page);
> -		left -= size;

Argh...
		if (left <= PAGE_SIZE - off)
			return maxsize;
> +		left -= PAGE_SIZE - off;
>  	}
>  	if (!npages)
>  		return -EFAULT;
> -	maxsize -= left;
> -	iov_iter_advance(i, maxsize);
> -	return maxsize;
> +	return maxsize - left;
>  }
>  
>  static ssize_t iter_xarray_populate_pages(struct page **pages, struct xarray *xa,
> -- 
> 2.30.2
>