From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 9DE68220F35 for ; Tue, 6 May 2025 08:10:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746519021; cv=none; b=hfFWjB9c38ilCY0VewW8f5MhHnGLWdtk4S4YtOY4DQk7o4Wy+OnlcD+RY/4jZOQjuvMQJhOuQIUGQ646SceAg38hrr7w6Bt45qewCyqmx/vgIwEZU51V8N/u8htGUHGyO+b7F27UQGT4bbI0AXDfpK22JiIT/+DU5+Ux/v9ePA8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746519021; c=relaxed/simple; bh=xPHtwcRyZypI0M/zn8r69qHb9Kf/LIapegrnkyfz0hM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LFgjUnsg+GhGagUVCb/4i8/Q3AbrIASVfAze+pQH1dRALx8OUvZNCO2fWqnOwFJ8tTdOYw9hzkprGi8akiMHPvXFRb4GoFzdR3hs4No+alwbiJ4Pdt5Qn4FK8iPWHNytU/KNwZcLlCBnRrbjP3eGA3WtmsI3u5UYl8pRHyoLiXM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=dpXyCir6; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="dpXyCir6" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=OzyOOjeOVLi3r7iK57XVv83fbG54a7AzVwvdvL8XGrc=; b=dpXyCir65jLVHUNe+M0mIzRPzT G6rN7Zfn/tfTYmDO19gLzwNPRYATVP8wwNUEuFeZIjb0Ukm02conF4KL7jKsWeEV2J5yVkBbt49DM 2jDuae7zp4hfDN5cqkegw5bKf1st9KoX5hmTfeqUbAb3+OUACL0aAwkfVajPPWkEqLv6DNYAqC5uM /fM/EZPirYwLuIQaOVNCeySXjw7ioJ7FeQHCYVlN7CYwTEuBwylfvCCa2rTUgnDXx56IEOQ78VwjR ncsVSGHk2YgZ3s64pIDBJWlYMdYp7OFBzYbM5kpqz7Ej2BnSf3ao2Hm+hwIUB2s/eK0nkghHp2YNh I3MZOCJw==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.2 #2 (Red Hat Linux)) id 1uCDNZ-0000000B6aE-0yMf; Tue, 06 May 2025 08:10:17 +0000 Date: Tue, 6 May 2025 01:10:17 -0700 From: Christoph Hellwig To: cel@kernel.org Cc: NeilBrown , Jeff Layton , Olga Kornievskaia , Dai Ngo , Tom Talpey , linux-nfs@vger.kernel.org, Chuck Lever , Roland Mainz Subject: Re: [PATCH] NFSD: Implement FATTR4_CLONE_BLKSIZE attribute Message-ID: References: <20250427163914.5053-1-cel@kernel.org> Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250427163914.5053-1-cel@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Sun, Apr 27, 2025 at 12:39:14PM -0400, cel@kernel.org wrote: > NFSD can return 0 here, as at least one client implementation we > are aware of (the Linux NFS client) treats 0 as meaning "CLONE has > no alignment restrictions". Usuaully clone does have a restriction, though. > Meanwhile we need to consult the nfsv4 Working Group to clarify the > meaning and use of the value of this attribute. Yeah, the attribute seems to be severly underspecified, i.e. it does not even provide a unit that the value is in. I think the only sane way out is an errate that makes 0 mean "not specified" and then provides the byte unit and maybe some other quirks. > + /* Linux filesystems have no clone alignment restrictions */ That is absolutely untrue as said above.