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 X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8C98DC43465 for ; Mon, 21 Sep 2020 15:20:18 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 3F69520756 for ; Mon, 21 Sep 2020 15:20:18 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3F69520756 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=zeniv.linux.org.uk Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 8B414900081; Mon, 21 Sep 2020 11:20:17 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 86540900083; Mon, 21 Sep 2020 11:20:17 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 70460900081; Mon, 21 Sep 2020 11:20:17 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0083.hostedemail.com [216.40.44.83]) by kanga.kvack.org (Postfix) with ESMTP id 5975F900072 for ; Mon, 21 Sep 2020 11:20:17 -0400 (EDT) Received: from smtpin14.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 17351181AEF1A for ; Mon, 21 Sep 2020 15:20:17 +0000 (UTC) X-FDA: 77287429674.14.ear06_44039f227146 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin14.hostedemail.com (Postfix) with ESMTP id BB0681801061E; Mon, 21 Sep 2020 15:20:10 +0000 (UTC) X-HE-Tag: ear06_44039f227146 X-Filterd-Recvd-Size: 2656 Received: from ZenIV.linux.org.uk (zeniv.linux.org.uk [195.92.253.2]) by imf35.hostedemail.com (Postfix) with ESMTP; Mon, 21 Sep 2020 15:20:10 +0000 (UTC) Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1kKNbm-003CHu-Vt; Mon, 21 Sep 2020 15:20:03 +0000 Date: Mon, 21 Sep 2020 16:20:02 +0100 From: Al Viro To: Christoph Hellwig Cc: Andrew Morton , Jens Axboe , Arnd Bergmann , David Howells , David Laight , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, sparclinux@vger.kernel.org, linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-aio@kvack.org, io-uring@vger.kernel.org, linux-arch@vger.kernel.org, linux-mm@kvack.org, netdev@vger.kernel.org, keyrings@vger.kernel.org, linux-security-module@vger.kernel.org Subject: Re: [PATCH 06/11] iov_iter: handle the compat case in import_iovec Message-ID: <20200921152002.GW3421308@ZenIV.linux.org.uk> References: <20200921143434.707844-1-hch@lst.de> <20200921143434.707844-7-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200921143434.707844-7-hch@lst.de> 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 Mon, Sep 21, 2020 at 04:34:29PM +0200, Christoph Hellwig wrote: > Use in compat_syscall to import either native or the compat iovecs, and > remove the now superflous compat_import_iovec, which removes the need for > special compat logic in most callers. Only io_uring needs special > treatment given that it can call import_iovec from kernel threads acting > on behalf of native or compat syscalls. Expose the low-level > __import_iovec helper and use it in io_uring to explicitly pick a iovec > layout. fs/aio.c part is not obvious... Might be better to use __import_iovec() there as well and leave the rest of aio.c changes to followup. > --- a/lib/iov_iter.c > +++ b/lib/iov_iter.c > @@ -1683,7 +1683,7 @@ static int compat_copy_iovecs_from_user(struct iovec *iov, > return ret; > } > > -static ssize_t __import_iovec(int type, const struct iovec __user *uvector, > +ssize_t __import_iovec(int type, const struct iovec __user *uvector, > unsigned nr_segs, unsigned fast_segs, struct iovec **iovp, > struct iov_iter *i, bool compat) > { Don't make it static in the first place, perhaps?