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 4C6412586EF; Mon, 14 Jul 2025 17:46:33 +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=1752515194; cv=none; b=pUOUEvf+vK35yTdF7P6jWcoazrhTlyD+tCZWmeDkvsHd0K3f0rLXetCb0SQK14rOE6r9D8Cb9xyF6c/D92S/s9sj4pFKCOWsEfRpJd5rwW2KFVeLsKCC8SzOsh/um0vjgMcbe/J4fRNkMPF0k30fuT0ChcjVabX5gc0wjElXj2w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752515194; c=relaxed/simple; bh=5PE6/IBiSWRv1ULmZKm7V6xmwg8/qTq1E3BHbh9lJX0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QEXlFZ9Y8+w7PK/1tR9hTvtHLd5/xHmb9+8sNqBeRGUErpI9aAXu0mGqjO/3jIKw/x5ADW9rQuONv5f+eEkpqEqCR5gbzaPlkPYzWHwqJVNTXsgVxm7kJDUv1rQHvkctDcw3wzIXx/TFyK3fBhUSuM8bUu1Akdmw3yKTWMeDtmc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CIhfGF/W; 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="CIhfGF/W" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 89375C4CEED; Mon, 14 Jul 2025 17:46:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1752515193; bh=5PE6/IBiSWRv1ULmZKm7V6xmwg8/qTq1E3BHbh9lJX0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=CIhfGF/WcV3IvhroaBY+lao5QWTelztEUk92CiJ4dfA/wJHxacVJU16Kmo7jgrAS+ Xd42ZyElE+lo/Zi6YcG1FCTQ++qrzuYyZ/DSV8zCmFWS+FAcIJpDXo4FcENO6X0+jH 2c/EK8ZpUAZJvo8d9n+9Jut3epql7gBgzA9L95HDxHyKIcDqQe+LdUEnjMskVQiYe6 JVJ9MZdG63hm0xa2my2l/+fNbuUN0wATZ6EJtFQZU78ta8R5QkMwtIpLmDHGGE7Pxe zL+wR7jEySuSDs8xtB/fQ5imH4nP9DN9SFJlVw2qKrwF7h0bfiPFOFz50AOVJq+GwT 5W8J6DiH+ufpA== Date: Mon, 14 Jul 2025 13:46:32 -0400 From: Mike Snitzer To: Christoph Hellwig Cc: Chuck Lever , Jeff Layton , NeilBrown , Olga Kornievskaia , Dai Ngo , Tom Talpey , Trond Myklebust , Anna Schumaker , linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [RFC PATCH v2 3/8] NFSD: filecache: add STATX_DIOALIGN and STATX_DIO_READ_ALIGN support Message-ID: References: <20250708160619.64800-1-snitzer@kernel.org> <20250708160619.64800-4-snitzer@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: On Thu, Jul 10, 2025 at 12:45:52AM -0700, Christoph Hellwig wrote: > On Tue, Jul 08, 2025 at 12:06:14PM -0400, Mike Snitzer wrote: > > Use STATX_DIOALIGN and STATX_DIO_READ_ALIGN to get and store DIO > > alignment attributes from underlying filesystem in associated > > nfsd_file. This is done when the nfsd_file is first opened for > > a regular file. > > Just as a little warning: these are unfortunately only supported by > very few file systems right now. For someone with a little bit of > time on their hand it would be nice to do a pass to set them for > all remaining direct I/O supporting file systems, which is only about > a dozen anyway. That's a good point. Meanwhile, I'll be sure to have the NFSD code (and NFS LOCALIO code later) be more defensive about the possibility of these attributes being 0 (due to lack of underlying filesystem support). Mike