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Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1qWyZ9-009PXu-J7; Fri, 18 Aug 2023 12:26:59 +0000 Date: Fri, 18 Aug 2023 13:26:59 +0100 From: Matthew Wilcox To: David Laight Cc: 'David Howells' , Linus Torvalds , Al Viro , Jens Axboe , Christoph Hellwig , Christian Brauner , Jeff Layton , "linux-fsdevel@vger.kernel.org" , "linux-block@vger.kernel.org" , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v3 2/2] iov_iter: Don't deal with iter->copy_mc in memcpy_from_iter_mc() Message-ID: References: <03730b50cebb4a349ad8667373bb8127@AcuMS.aculab.com> <20230816120741.534415-1-dhowells@redhat.com> <20230816120741.534415-3-dhowells@redhat.com> <608853.1692190847@warthog.procyon.org.uk> <3dabec5643b24534a1c1c51894798047@AcuMS.aculab.com> <665724.1692218114@warthog.procyon.org.uk> <1748360.1692358952@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: A91CD12002B X-Rspam-User: X-Rspamd-Server: rspam04 X-Stat-Signature: iuxit7oj3sugm1nddp3i63osin5jsfn5 X-HE-Tag: 1692361633-402840 X-HE-Meta: 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 70Y+O5gr aN6Aw/eBse4ESg6Yu0vTIjoWSCmerpHP6r/d44xcXFVobEb8KckQQZbfRg6z7VGg6SNPiWwL+aHEFt4b21yfHr7SerqxsTLQA3Viu+7CEMXlwVwX7Yv+BlPAVgBtcJcUUcaTceXZy9Wz5XYoxyXQOz4a5XzzBthwmCN7Kw7vpyqiXjqUXh0szRCJiop66IWPACxBJnldHWJI8Fv7KM7Th4+xJE7YvttO8S9lF X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Aug 18, 2023 at 12:16:23PM +0000, David Laight wrote: > > > + ITER_IOVEC = 1, > > > + ITER_UBUF = 2, > > > + ITER_KVEC = 4, > > > + ITER_BVEC = 8, > > > + ITER_XARRAY = 16, > > > + ITER_DISCARD = 32, > > IIRC Linus had type:6 - that doesn't leave any headroom > for additional types (even though they shouldn't proliferate). I have proposed an ITER_KBUF in the past (it is to KVEC as UBUF is to IOVEC). I didn't care enough to keep pushing it, but it's clearly a common idiom.