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To:     Christoph Hellwig <hch@infradead.org>
Cc:     Bart Van Assche <bart.vanassche@gmail.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        David Howells <dhowells@redhat.com>,
        Matthew Wilcox <willy@infradead.org>,
        Jens Axboe <axboe@kernel.dk>, Jan Kara <jack@suse.cz>,
        Jeff Layton <jlayton@kernel.org>,
        Logan Gunthorpe <logang@deltatee.com>,
        linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        "Martin K. Petersen" <martin.petersen@oracle.com>,
        Douglas Gilbert <dgilbert@interlog.com>
Subject: Re: [PATCH v5 3/9] iov_iter: Use IOCB/IOMAP_WRITE if available
 rather than iterator direction
From:   "Martin K. Petersen" <martin.petersen@oracle.com>
Organization: Oracle Corporation
Message-ID: <yq1o7r1ucin.fsf@ca-mkp.ca.oracle.com>
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Date:   Fri, 13 Jan 2023 20:33:13 -0500
In-Reply-To: <Y8Ds9JbWNGlWnoj9@infradead.org> (Christoph Hellwig's message of
        "Thu, 12 Jan 2023 21:32:36 -0800")
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Christoph,

> Yeah.  And that weird (ab)use of blk_rq_map_user_iov into preallocated
> pages in sg has been a constant source of pain.  I'd be very happy to
> make it match the generic SG_IO implementation and either do
> get_user_pages or the normal bounce buffering implemented in the
> common code.

Yes, it would be nice to get that cleaned up.

-- 
Martin K. Petersen	Oracle Linux Engineering