From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 09A39150997; Fri, 31 May 2024 10:28:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717151331; cv=none; b=t2X+jqxz2oEJ1bVOhee9SzPLVpC7goBwgVaGa9W9T1z2jKwvkS3up8dy3omtY/OSfntqOorC26vjMY5SsPaLuPr9dXv0ER9TPEPh7HY6L870WDbhk2gMe0GdHI2n1kv0YlQC/DW9VpOk2du2111LtQRZbdxkudWZ5R/MrE07oLw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717151331; c=relaxed/simple; bh=KB7cZUDNKLMAO8YBjAtoXYlExNlywx7Yb8mKsAAluKc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=kJCwjN8n/x15hJnzDa9OgzAr5ZHR72MFIfkOFYKl7SeQLbqSul07YWzQqhReOnPMyTOJ+D7YbDhOCskQOuGKzfJY9Ds39TQpzGx+vTTF76jNV+I9CfF6V9KhngkqL6T39z5ifJd0CWjqS+EzVgWm6k2qkcoxpTQnR95sD43K58M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cIpelTrE; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="cIpelTrE" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 930E2C116B1; Fri, 31 May 2024 10:28:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717151330; bh=KB7cZUDNKLMAO8YBjAtoXYlExNlywx7Yb8mKsAAluKc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cIpelTrE1vbY2pI4N067jdvvohc44mf5PUJCwDpi+SWltx44rFhuGRfBFXTQrOFAF kkmPBy+/nrjlRzsi1RVHdtsqTz7RoeTmtAwXiq7bTRcqq6gPBAYwoxRElKqEqVqugj kr1HcKuC9vuF4HCoG0hoNYqyu7DfQJjyqmhdjXQm+L0WXIDfJtTZEie6cLumqEQ8dm 6eISPD5/1sH43FygdmX0YHAaTbVqc4GMN3v9jdyivbuQ8tZOXEpPqfp9m2d2TI3GhR DmCgIvSUjN/5i8DC/qNuykn4I9DyU6d9ehxxx+blgg0F6iCM1CF2UyNWHL3kvZE6MA Lru+PtSncp43A== Date: Fri, 31 May 2024 12:28:44 +0200 From: Christian Brauner To: Christoph Hellwig Cc: Jan Kara , Aleksa Sarai , Alexander Viro , Chuck Lever , Jeff Layton , Amir Goldstein , Alexander Aring , linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org, linux-api@vger.kernel.org Subject: Re: [PATCH RFC v2] fhandle: expose u64 mount id to name_to_handle_at(2) Message-ID: <20240531-beizeiten-mythisch-667a70d59a82@brauner> References: <20240527133430.ifjo2kksoehtuwrn@quack3> <20240528-wachdienst-weitreichend-42f8121bf764@brauner> <20240528-gesell-evakuieren-899c08cbfa06@brauner> <20240528-gipfel-dilemma-948a590a36fd@brauner> <20240529-marzipan-verspannungen-48b760c2f66b@brauner> Precedence: bulk X-Mailing-List: linux-api@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: > I don't understand what you mean. If we hand out file handles with I don't think adding another highly privileged interface in opposition to exposing the mount id is warranted. The new mount id exposure patch is a performance improvement for existing use-cases to let userspace avoid additional system calls. Because as Aleksa showed in the commit message there's ways to make this race-free right now. The patch hasn't gained any Acks from Amir or Jeff so it's obviously not going to get merged. So really, I don't want another interface that goes from arbitrary superblock to file hidden behind yet another global capability check.