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 17232C433F5 for ; Wed, 4 May 2022 12:09:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345769AbiEDMNV (ORCPT ); Wed, 4 May 2022 08:13:21 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48754 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242185AbiEDMNT (ORCPT ); Wed, 4 May 2022 08:13:19 -0400 Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9D197252AB for ; Wed, 4 May 2022 05:09:43 -0700 (PDT) Received: by mail-pj1-x102a.google.com with SMTP id a15-20020a17090ad80f00b001dc2e23ad84so4995098pjv.4 for ; Wed, 04 May 2022 05:09:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel-dk.20210112.gappssmtp.com; s=20210112; h=message-id:date:mime-version:user-agent:subject:content-language:to :cc:references:from:in-reply-to:content-transfer-encoding; bh=WN26lsagJL4pdNyPEQ7HfFpD1NYMfhKOpFKAu+2HvXc=; b=eB+RA9Xn/HO7qvVXckDmKIxv3Rdk20fFxZXIJsbgSnU5xH11QlIbEk+41sSRfiGIYb 2nvMYN3XJZB6LOyjUWjkt7VOrYe2d7LS7aJFstRKrw3vqC/Oqclo21b2nvOg5itOwE7A ZDNy7cs9VaTmKQUCQM4TdYrN21zXtxmWPKdHQQCZTqQnQ+U0QHrw3XuoED2zq6aNxSNd 8wZajNjmxNv+5uEK9tmaV+jxKTHQAP26KDyjLr+7YJcBag7DYjVE8aiQV6ltpWAOjDjv upIuyuyU4KNewWXWIrN7VsA7foTz4EruCxYif6Tb7cNy1nAzX0pIH2NpQI3DYzM1k8S3 trQw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:cc:references:from:in-reply-to :content-transfer-encoding; bh=WN26lsagJL4pdNyPEQ7HfFpD1NYMfhKOpFKAu+2HvXc=; b=0tzm0si39AJ0HRxS9O38L6JRFf4oMwwpZU3NxM+kfPfPnjsVnPAH3H3qnyFcE5Qb6y /NNtkKrB7b+0hBrFqG0XNClTjN+wvjksAyTrsRUgkmpnWCvxG7RLN1iFPZ5FvNyvbeWE 1wOvYg+8O9mmtRnX84rNFKbHhCnmF33SPk41xwhHkXbJh5kcf0Xb9JVMmrM2VTsMbKw4 XbIO4nYDtID69f1x8AlgxOuK3YCbcNglsrWve0BjhFGNt7pESOw8skiTZGVrf+E5mCX/ 5yDBlLn0gAxtXCAYO0nD/J1aKZweEQmQSa5jQ1Lqfh1x28GHKDZKbBHhNMLkJTmlBKi8 4b0A== X-Gm-Message-State: AOAM533kacnjZR+LtVW/4k03xS4kXSnxAMa5+c4ryWR1K0DwemoBhlyP GFqjTPim7TDb48nNjeuMClSjng== X-Google-Smtp-Source: ABdhPJyI9yHw5N7Z274pvOUBNLkDQslDEoywKffSOV3ZxsSOQ1SpbdjrK0LJm3PQ5VuOZ6r4UCKqPQ== X-Received: by 2002:a17:90b:4f92:b0:1cd:3a73:3a46 with SMTP id qe18-20020a17090b4f9200b001cd3a733a46mr10136443pjb.66.1651666182660; Wed, 04 May 2022 05:09:42 -0700 (PDT) Received: from [192.168.4.166] (cpe-72-132-29-68.dc.res.rr.com. [72.132.29.68]) by smtp.gmail.com with ESMTPSA id p4-20020a1709028a8400b0015e8d4eb257sm8186529plo.161.2022.05.04.05.09.41 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 04 May 2022 05:09:42 -0700 (PDT) Message-ID: <812fe134-3e69-294b-fd05-9a8366e17467@kernel.dk> Date: Wed, 4 May 2022 06:09:40 -0600 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux aarch64; rv:91.0) Gecko/20100101 Thunderbird/91.8.1 Subject: Re: [PATCH v3 1/5] fs,io_uring: add infrastructure for uring-cmd Content-Language: en-US To: Kanchan Joshi , Christoph Hellwig Cc: Pankaj Raghav , io-uring@vger.kernel.org, linux-nvme@lists.infradead.org, Pavel Begunkov , Ming Lei , Luis Chamberlain , Stefan Roesch , gost.dev@samsung.com, Kanchan Joshi References: <20220503184831.78705-1-p.raghav@samsung.com> <20220503184831.78705-2-p.raghav@samsung.com> <20220503205202.GA9567@lst.de> From: Jens Axboe In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 5/4/22 9:12 AM, Kanchan Joshi wrote: >> @@ -64,16 +63,19 @@ struct io_uring_sqe { >> __u32 file_index; >> }; >> union { >> - __u64 addr3; >> - __u64 cmd; >> + struct { >> + __u64 addr3; >> + __u64 __pad2[1]; >> + } small; > > Thinking if this can cause any issue for existing users of addr3, i.e. > in the userspace side? Since it needs to access this field with > small.addr3. > Jens - is xattr infra already frozen? It's not, as it's not upstream yet. But I don't think we need to change it, just make the two structs unnamed instead. That also avoids awkward small/big prefixes. -- Jens Axboe