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Date:   Mon, 13 Feb 2023 15:24:55 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     David Howells <dhowells@redhat.com>
Cc:     Jens Axboe <axboe@kernel.dk>, Al Viro <viro@zeniv.linux.org.uk>,
        Christoph Hellwig <hch@infradead.org>, 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, Christoph Hellwig <hch@lst.de>,
        John Hubbard <jhubbard@nvidia.com>
Subject: Re: [PATCH 3/4] splice: Use init_sync_kiocb() in
 filemap_splice_read()
Message-ID: <Y+pWRx2ly/qdFq9k@casper.infradead.org>
References: <20230213134619.2198965-1-dhowells@redhat.com>
 <20230213134619.2198965-4-dhowells@redhat.com>
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On Mon, Feb 13, 2023 at 01:46:18PM +0000, David Howells wrote:
> Use init_sync_kiocb() in filemap_splice_read() rather than open coding it
> and filter out IOCB_NOWAIT since the splice is synchronous.

If the user has asked for NOWAIT and the splice is going to be
synchronous, shouldn't we rather return -EWOULDBLOCK here?  Or
does this not block?

IOW, this either does the wrong thing, or it does something that's
irrelevant.