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 354CF2309A3; Mon, 7 Apr 2025 09:15:46 +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=1744017348; cv=none; b=hH5CLq5YwC/iU5KsKyV+/26N5IDp3Cm8m5MPUPoKIYJ00ud9wYFt/7+Fv3mHzZ7CqiUsGYi+I+lD6Vy/p4tstP6oxYf9fynq5kEFOdCl5fOcyssVGGibJX+JDd3VHPEyg68NRzlHr2TTrNj9x6UHnVxovDDFZNpvazT4nf1tSEI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1744017348; c=relaxed/simple; bh=ND5TFDjwajhpW3p14uRN8gBouffujWQSboBCcOhvDB4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ZTmjpwwDSsl6l1bcfC9ekImkP78PwSZC8DuBja61Ef8mm1EjNtGdZwd0nPsBFZBU3s1+ea3su69hreuTNTYK3gNqxG+J8FjGHBOBm5uoPpk6lyXJVs0iyCwFhVQxgUfq5uoNo9OdgoBqljOLeMPTyjEOAtYKzceaA+3fsxh/Xk8= 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=gWQqKVXA; 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="gWQqKVXA" 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=ofqWwqYhXMMlq9izH/X2Vybg9guxywDxyDKd2Dx3UiE=; b=gWQqKVXAMd8yKk5YBfYHP8zEkI vzJHXkuDQWitK/baGDY1h7cbxIaGjM1d+Sn59xfQp2R0n36Z2LKWbjq/QUep+k1dchsKnkA4mqqSk MLCiavZQM1PGpkgxshtqMpZqQsxMlM9nkhRM1+AyhpdfaxbiyvumrD3TmhcEuOFp9kIpYx72LmCvt l/8JZquo6wT0nZFH5lKmhoY30BtmcaNnnXNOKJJ3leYs+/4cgieFpeG47l3SAYLiqResroUBXDnCX x/yCb1VIhwYFYq9ovuhn8NuO6ZOXcUespBWbVPEPhgT8/YXXUznrHpfjRI6hRVvC5r6/q1CUxXC4i PuhrNIqg==; Received: from hch by bombadil.infradead.org with local (Exim 4.98.1 #2 (Red Hat Linux)) id 1u1ia2-0000000H9UD-25Dq; Mon, 07 Apr 2025 09:15:46 +0000 Date: Mon, 7 Apr 2025 02:15:46 -0700 From: Christoph Hellwig To: Matthew Wilcox Cc: Christoph Hellwig , Alistair Popple , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RFC 0/6] Allow file-backed or shared device private pages 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 Wed, Mar 26, 2025 at 02:14:59AM +0000, Matthew Wilcox wrote: > So, there's no need to put DEVICE_PRIVATE pages in the page cache. > Instead the GPU will take a copy of the page(s). We agreed that there > will have to be some indication (probably a folio flag?) that the GPU has > or may have a copy of (some of) the folio so that it can be invalidated > if the page is removed due to truncation / eviction. Sounds like layout leases used for pnfs.