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 26B91C7619A for ; Wed, 12 Apr 2023 13:53:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230263AbjDLNxh (ORCPT ); Wed, 12 Apr 2023 09:53:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229769AbjDLNxh (ORCPT ); Wed, 12 Apr 2023 09:53:37 -0400 Received: from mail-wm1-f47.google.com (mail-wm1-f47.google.com [209.85.128.47]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 29A5C269D; Wed, 12 Apr 2023 06:53:35 -0700 (PDT) Received: by mail-wm1-f47.google.com with SMTP id he13so11588055wmb.2; Wed, 12 Apr 2023 06:53:35 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1681307613; x=1683899613; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=VMUJR0ziXAKL97/Fc/1XtofHlhmh4dw/ld6x3YBdDJA=; b=c5MznV+FSP9GQAzDIL6X6/HEUkHgbTxoYZJJLSLa7kNIz6rQjxCusoEcnI2o4F16x0 pK1ouAwgtZkTGMWiEbd/iuZuC7jNucujWU95hUNkGWnIjlmmqsHCGZy/w2WGGinHkVyP zWa2LL436y+y8u46Uw7UAgry6owUNKo/r1hN7mMXp/w9IiLamDP27IXESFTWin5PKcDE qoh6B+gPYHk77EjioF1tMS41pxjVSIk5tggZXTmSmDFVECZsOQSjqPZPaUns9yP6/OSd Pq/ZKPhP2tLmUpmMCMdV2/0YIShlgD7I20mx1ZhvXnEPZu1SSr85pVZIphIAanfPWFMk rjyw== X-Gm-Message-State: AAQBX9cF7iP+isOo70nbHKm20K+lhRQfKHaHInTm2BbreG2iJ3naTCfl BFVGgXi4xe5fh3j4TfGaPFY= X-Google-Smtp-Source: AKy350a7suuVGRUdrJzLxBrp2tG07AraETPQmB+GH8IgY+nxp+FZeY/RzoijoKarE9xMi9XKLFzzAw== X-Received: by 2002:a05:600c:3658:b0:3ef:7594:48cc with SMTP id y24-20020a05600c365800b003ef759448ccmr9450881wmq.23.1681307613395; Wed, 12 Apr 2023 06:53:33 -0700 (PDT) Received: from gmail.com (fwdproxy-cln-024.fbsv.net. [2a03:2880:31ff:18::face:b00c]) by smtp.gmail.com with ESMTPSA id m2-20020a05600c3b0200b003f0652084b8sm2540633wms.20.2023.04.12.06.53.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Apr 2023 06:53:32 -0700 (PDT) Date: Wed, 12 Apr 2023 06:53:30 -0700 From: Breno Leitao To: Jens Axboe Cc: Willem de Bruijn , David Ahern , Willem de Bruijn , io-uring@vger.kernel.org, netdev@vger.kernel.org, kuba@kernel.org, asml.silence@gmail.com, leit@fb.com, edumazet@google.com, pabeni@redhat.com, davem@davemloft.net, dccp@vger.kernel.org, mptcp@lists.linux.dev, linux-kernel@vger.kernel.org, matthieu.baerts@tessares.net, marcelo.leitner@gmail.com Subject: Re: [PATCH 0/5] add initial io_uring_cmd support for sockets Message-ID: References: <75e3c434-eb8b-66e5-5768-ca0f906979a1@kernel.org> <67831406-8d2f-feff-f56b-d0f002a95d96@kernel.dk> <643573df81e20_11117c2942@willemb.c.googlers.com.notmuch> <036c80e5-4844-5c84-304c-7e553fe17a9b@kernel.dk> <64357608c396d_113ebd294ba@willemb.c.googlers.com.notmuch> <19c69021-dce3-1a4a-00eb-920d1f404cfc@kernel.dk> <64357bb97fb19_114b22294c4@willemb.c.googlers.com.notmuch> <20cb4641-c765-e5ef-41cb-252be7721ce5@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20cb4641-c765-e5ef-41cb-252be7721ce5@kernel.dk> Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Tue, Apr 11, 2023 at 09:28:29AM -0600, Jens Axboe wrote: > On 4/11/23 9:24?AM, Willem de Bruijn wrote: > > Jens Axboe wrote: > >> On 4/11/23 9:00?AM, Willem de Bruijn wrote: > >> But that doesn't work, because sock->ops->ioctl() assumes the arg is > >> memory in userspace. Or do you mean change all of the sock->ops->ioctl() > >> to pass in on-stack memory (or similar) and have it work with a kernel > >> address? > > > > That was what I suggested indeed. > > > > It's about as much code change as this patch series. But it avoids > > the code duplication. > > Breno, want to tackle that as a prep patch first? Should make the > functional changes afterwards much more straightforward, and will allow > support for anything really. Absolutely. I just want to make sure that I got the proper approach that we agreed here. Let me explain what I understood taking TCP as an example: 1) Rename tcp_ioctl() to something as _tcp_ioctl() where the 'arg' argument is now just a kernel memory (located in the stack frame from the callee). 2) Recreate "tcp_ioctl()" that will basically allocate a 'arg' in the stack and call _tcp_ioctl() passing that 'arg' argument. At the bottom of this (tcp_ioctl() function) function, call `put_user(in_kernel_arg, userspace_arg) 3) Repeat it for the 20 protocols that implement ioctl: ag "struct proto .* = {" -A 20 net/ | grep \.ioctl net/dccp/ipv6.c .ioctl = dccp_ioctl, net/dccp/ipv4.c .ioctl = dccp_ioctl, net/ieee802154/socket.c .ioctl = dgram_ioctl, net/ipv4/udplite.c .ioctl = udp_ioctl, net/ipv4/raw.c .ioctl = raw_ioctl, net/ipv4/udp.c .ioctl = udp_ioctl, net/ipv4/tcp_ipv4.c .ioctl = tcp_ioctl, net/ipv6/raw.c .ioctl = rawv6_ioctl, net/ipv6/tcp_ipv6.c .ioctl = tcp_ioctl, net/ipv6/udp.c .ioctl = udp_ioctl, net/ipv6/udplite.c .ioctl = udp_ioctl, net/l2tp/l2tp_ip6.c .ioctl = l2tp_ioctl, net/l2tp/l2tp_ip.c .ioctl = l2tp_ioctl, net/phonet/datagram.: .ioctl = pn_ioctl, net/phonet/pep.c .ioctl = pep_ioctl, net/rds/af_rds.c .ioctl = rds_ioctl, net/sctp/socket.c .ioctl = sctp_ioctl, net/sctp/socket.c .ioctl = sctp_ioctl, net/xdp/xsk.c .ioctl = sock_no_ioctl, net/mptcp/protocol.c .ioctl = mptcp_ioctl, Am I missing something? Thanks!