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Date:   Thu, 24 Jun 2021 07:41:12 +0100
From:   Christoph Hellwig <hch@infradead.org>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Omar Sandoval <osandov@osandov.com>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Dave Chinner <david@fromorbit.com>,
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        Linux API <linux-api@vger.kernel.org>,
        Kernel Team <kernel-team@fb.com>,
        Dave Chinner <dchinner@redhat.com>
Subject: Re: [PATCH RESEND x3 v9 1/9] iov_iter: add copy_struct_from_iter()
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I'm also really worried with overloading the regular r/w path and
iov_iter with ever more special cases.  We already have various
performance problems in the path, and adding more special cases ain't
gonna help.