Date:   Wed, 8 Feb 2023 17:21:27 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     David Howells <dhowells@redhat.com>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Jens Axboe <axboe@kernel.dk>,
        Al Viro <viro@zeniv.linux.org.uk>, Jan Kara <jack@suse.cz>,
        Jeff Layton <jlayton@kernel.org>,
        David Hildenbrand <david@redhat.com>,
        Jason Gunthorpe <jgg@nvidia.com>,
        Logan Gunthorpe <logang@deltatee.com>,
        Hillf Danton <hdanton@sina.com>, linux-fsdevel@vger.kernel.org,
        linux-block@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org,
        syzbot+a440341a59e3b7142895@syzkaller.appspotmail.com,
        Christoph Hellwig <hch@lst.de>,
        John Hubbard <jhubbard@nvidia.com>
Subject: Re: [PATCH v12 01/10] vfs, iomap: Fix generic_file_splice_read() to
 avoid reversion of ITER_PIPE
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 <20230207171305.3716974-2-dhowells@redhat.com>
 <176199.1675872591@warthog.procyon.org.uk>
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On Wed, Feb 08, 2023 at 04:09:51PM +0000, David Howells wrote:
> @@ -2688,7 +2689,7 @@ ssize_t filemap_read(struct kiocb *iocb, struct iov_iter *iter,
>  		if (unlikely(iocb->ki_pos >= i_size_read(inode)))
>  			break;
>  
> -		error = filemap_get_pages(iocb, iter, &fbatch);
> +		error = filemap_get_pages(iocb, iov_iter_count(iter), &fbatch);

What's the point in iov_iter_count() anyway?  It's more characters
than iter->count, so why not use it directly?