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 A47DE29A1; Thu, 16 Jan 2025 05:40:39 +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=1737006040; cv=none; b=OaY8AlK+Z/oSbX1lPlMsf5ctnFGKzpUcJ6823bBwxvIJCFcdrtoxHKNfzQTEYjbOjgv1Tjw3TNYK5r43ZnZE2EFVnsAAKUlnnkRsJpkFcUrCZ83gXrGuvWAJnP53fZdmlyuyhzNELcrmFuNjdGuB7l4Ydg3UHoR7HMC4SMF9Ni0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1737006040; c=relaxed/simple; bh=vgYCi+/alnDBSi7Q+Ztn2UqfnjMah6L/vWReeftHiF4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UsMYPKeCas+4W/UnxCH63Fpj6p1vqUdPHWEL84yjcP00u+4i/M+CIvCsOKLr4KLIsQqANcioaLoPNkaSDK+W/3lAHjJzIV9xoefe68kq2/y7j89ovqTW+X5cE0WxgJlQ3WULIJQTynizW+hpUp8SXd9FTg6U0mbY5tog5/rPNko= 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=l++9kEB5; 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="l++9kEB5" 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=sM9RJti6gPYuB5Hi7Zwv62M/fGmbF72HOLsXcvXcPo4=; b=l++9kEB5aV8aEQTB+3H51zH8ng bHUZcDfSidqbsjIYGBaxjo0jPSAt5kOZYlrZj/K2T38KxfjeO77ELgM4HXq4ihBB2kbR+BqOukdFk 8nrNvGERMbS0bhgbJKeNph4VdIL0VSYEHhz3oFKMfVCm5KsGiNOdCHt7u9sEDW0PIgtcfG90ZizE7 dV1Aj7n4w3SecX0iduDIXy718MnVQtepeu27F0Ldhra5yoB4+yV55dcmKnQk36G+anxMPhqzjn0tH mevqRmBzmB+P6aW5LwkhYFIsqXVtQzpw+sKny1ufrpFTXbDcfT7POQPkcN5tns4NkAARj94kyjanZ RaV8y3wQ==; Received: from hch by bombadil.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1tYIcQ-0000000DtcJ-45PG; Thu, 16 Jan 2025 05:40:38 +0000 Date: Wed, 15 Jan 2025 21:40:38 -0800 From: Christoph Hellwig To: Anna Schumaker Cc: lsf-pc@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, Linux NFS Mailing List Subject: Re: [LSF/MM/BPF TOPIC] Implementing the NFS v4.2 WRITE_SAME operation: VFS or NFS ioctl() ? Message-ID: References: Precedence: bulk X-Mailing-List: linux-fsdevel@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: X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Tue, Jan 14, 2025 at 04:38:03PM -0500, Anna Schumaker wrote: > I've seen a few requests for implementing the NFS v4.2 WRITE_SAME [1] operation over the last few months [2][3] to accelerate writing patterns of data on the server, so it's been in the back of my mind for a future project. I'll need to write some code somewhere so NFS & NFSD can handle this request. I could keep any implementation internal to NFS / NFSD, but I'd like to find out if local filesystems would find this sort of feature useful and if I should put it in the VFS instead. Well, one actual not very detailed request, and one question from a poster who just asks random questions on the list all the time for no good reason. If you care about it prototype first, check is feasible and see if it gives the expected results. After that you can report back with the findings and have an architectural discussion. But unless that gets stuck you should be easily do that on the list instead of wasting meetings slots on hand wavy stuff.