From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CAFCEC43334 for ; Tue, 28 Jun 2022 12:23:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231430AbiF1MXT (ORCPT ); Tue, 28 Jun 2022 08:23:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52176 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345667AbiF1MXP (ORCPT ); Tue, 28 Jun 2022 08:23:15 -0400 Received: from sin.source.kernel.org (sin.source.kernel.org [IPv6:2604:1380:40e1:4800::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 414F31261B for ; Tue, 28 Jun 2022 05:23:14 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by sin.source.kernel.org (Postfix) with ESMTPS id AF476CE1FFF for ; Tue, 28 Jun 2022 12:23:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 101D1C341CA; Tue, 28 Jun 2022 12:23:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1656418991; bh=vV3rOs0nJ1Hncp0+OvrmY7Qaih2OrEBI6Tiohz8l4Tc=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=W9otc76k9rtFNWqS5DWTsXKhOvRNPYtB59XZV6nhgqnPYyNjko9XOElsuLo9A1zEw x3Y4x5YmfupO/fZE1DEOOG+iiixf7jZj2CjmdEUtWsbKI8XoCxub5yKgXjkynivoYJ VKXaHVoMNq95s9AbuL+XFS4qyb6Ij1dm6iZQaRf0bsDaDmEJqdQwO9/Ck1Dnkxyr7x TLYXdtM2S83looCotwde/sL5Gdg2uksyf7VIZVbuZHMxlSQmtspeOmM+YbCqtdNxBI RAs9yCsmqKnVTwR6FAr+5rTmDBguzraAK/6UiBSLk9XOCqBpxeO7yiFCfr9l74EBAb BllCgxoNL5RLQ== Message-ID: Subject: Re: [PATCH 44/44] expand those iov_iter_advance()... From: Jeff Layton To: Al Viro , linux-fsdevel@vger.kernel.org Cc: Linus Torvalds , Jens Axboe , Christoph Hellwig , Matthew Wilcox , David Howells , Dominique Martinet , Christian Brauner Date: Tue, 28 Jun 2022 08:23:08 -0400 In-Reply-To: <20220622041552.737754-44-viro@zeniv.linux.org.uk> References: <20220622041552.737754-1-viro@zeniv.linux.org.uk> <20220622041552.737754-44-viro@zeniv.linux.org.uk> Content-Type: text/plain; charset="ISO-8859-15" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.44.2 (3.44.2-1.fc36) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Wed, 2022-06-22 at 05:15 +0100, Al Viro wrote: > Signed-off-by: Al Viro > --- > lib/iov_iter.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) >=20 > diff --git a/lib/iov_iter.c b/lib/iov_iter.c > index a8045c97b975..79c86add8dea 100644 > --- a/lib/iov_iter.c > +++ b/lib/iov_iter.c > @@ -1284,7 +1284,8 @@ static ssize_t iter_xarray_get_pages(struct iov_ite= r *i, > return 0; > =20 > maxsize =3D min_t(size_t, nr * PAGE_SIZE - offset, maxsize); > - iov_iter_advance(i, maxsize); > + i->iov_offset +=3D maxsize; > + i->count -=3D maxsize; > return maxsize; > } > =20 > @@ -1373,7 +1374,13 @@ static ssize_t __iov_iter_get_pages_alloc(struct i= ov_iter *i, > for (int k =3D 0; k < n; k++) > get_page(p[k] =3D page + k); > maxsize =3D min_t(size_t, maxsize, n * PAGE_SIZE - *start); > - iov_iter_advance(i, maxsize); > + i->count -=3D maxsize; > + i->iov_offset +=3D maxsize; > + if (i->iov_offset =3D=3D i->bvec->bv_len) { > + i->iov_offset =3D 0; > + i->bvec++; > + i->nr_segs--; > + } > return maxsize; > } > if (iov_iter_is_pipe(i)) Why do this? iov_iter_advance makes it clearer as to what's going on here. --=20 Jeff Layton