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 5D31217E908; Wed, 17 Jul 2024 09:53:35 +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=1721210016; cv=none; b=olQdgiuemRb1fqdDkvYaYJ8Lli/y7sKGol00bgfbgyUCn/GUg0xzbGkseM8RYZLK1tKPXuXeOYzixmCE1vnGFA/VTSjhxuXPF+vJGMNvO5+PKyG/aHeEYoq7f+bNahs0zalix1EWVNj72pvyyo09/iNW11hHTMKNdiy/hreZx5o= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721210016; c=relaxed/simple; bh=N5KTE/RBiUwGRlJgeXiZSHiX9FdHVUBgtTpGL78tPcw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=QsoJroyPbklhaITzXfGE1iiG21DXneT6hXndQ2QaAs3QQjtNlnNhxXhyoNkF3dEsaO2dtysabHGC2G9/nDv4IxpeHbVZd0Egwp5qAZ9Nl9LZugqcD09QpwXlZUX5LzzxFna4FvVG7PB2gORRd3kOMEmgmsD2bdRmKATKtfQEg8M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Uen35YsQ; 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="Uen35YsQ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19237C32782; Wed, 17 Jul 2024 09:53:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1721210015; bh=N5KTE/RBiUwGRlJgeXiZSHiX9FdHVUBgtTpGL78tPcw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Uen35YsQIUNtqnlSRyao9ajeFQ9ahKFjyxKoo+bhHE5G+BV6gnn6/M5U7VeMN9oJQ l+H5gC2chPsxGOTiMWURSFyb6M1P3LNC2ga9r1kdw1Ek44fchA0kOrtmqpeBXvRxFx m7FYcYaffeDvpKdIZzfNMidVqtqicewHIuPwgjaCqPFobM30cO9J89BdZdksz4dcOU T4sR+XTy4bFxAZUEG3na6c9GAwjds9S6/zh78yrl5aLYPqXvHN41S9pXw7cODdhvoF 6KkaSK/CqvkplM/BL2K1tWROSV0FlWBDTK8tt9LeqNr4y5/K5JxZiMhT6wh89TTqWZ ovvhmZaWudAGg== Date: Wed, 17 Jul 2024 12:53:30 +0300 From: Leon Romanovsky To: Christoph Hellwig Cc: Robin Murphy , Joerg Roedel , Will Deacon , Marek Szyprowski , Easwar Hariharan , linux-kernel@vger.kernel.org, iommu@lists.linux.dev, Jason Gunthorpe Subject: Re: [PATCH v1 2/2] dma: Add IOMMU static calls with clear default ops Message-ID: <20240717095330.GH5630@unreal> References: <7758cbe20bfd34506d943bb93097565b9c4dced4.1721041611.git.leon@kernel.org> <20240717082145.GA15484@lst.de> <20240717084713.GG5630@unreal> <20240717085652.GA18554@lst.de> Precedence: bulk X-Mailing-List: linux-kernel@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: <20240717085652.GA18554@lst.de> On Wed, Jul 17, 2024 at 10:56:52AM +0200, Christoph Hellwig wrote: > On Wed, Jul 17, 2024 at 11:47:13AM +0300, Leon Romanovsky wrote: > > It will cause to the situation where "struct device" memory footprint > > will increase, while we still need to keep dma_ops for archs that don't > > want to use default IOMMU. > > It won't. Even with the new bit we still have 28 more spare bits next > to it :) > > > Because dma_ops pointer exists anyway and has already specific flags. I > > decided to take evolutive approach and add a new flag to it, instead of > > revolutionary approach and add a new field to struct device. > > The point is that with a little more work we can actually kill that > for common configuration. For non-Xen setups that basically just means > removing the dummy ops, so it's a pretty big quick win. No problem, I'll do it. Thanks