From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailout1.w1.samsung.com (mailout1.w1.samsung.com [210.118.77.11]) (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 13C5320B1F4 for ; Tue, 8 Jul 2025 11:45:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=210.118.77.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751975128; cv=none; b=o19zvcNF6Sd49vSTubEbVZKRXfjGeU1JGgb+VHymLmGc3u+H6Ib+N1nIbZ+qCsM4B4umqeWUZXVVvWX5i0V1EM1xgXc2dv1qeQ2aWU/XZyrifqtkvDa+yts/0K4dQNsg+HveRDXIYK7vDeYYgQ7+HEh1ywH9ESW6jUzd26uVIAc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1751975128; c=relaxed/simple; bh=dDGmDdXbAVgOpktFUq0Y8CUWVS+LmZQ4NuInAHKnznw=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:From:In-Reply-To: Content-Type:References; b=nA6kVgAfIUgSGS+5Vq4hfKfTWPAsZ1WQgOvSrkgh71KlT8Z9ivgE9O5JUsgs5WXKyrhBkNwL7mH/z4RCVLYb39etZF6i7fMpmBxqzs394S/hultxsF6Tv4YWA7HD9FXFTFyMN0mCmHWVlVkAWWkZsP9dQvclrea1pjPtNYaxLKI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com; spf=pass smtp.mailfrom=samsung.com; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b=hTSmuD7o; arc=none smtp.client-ip=210.118.77.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=samsung.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b="hTSmuD7o" Received: from eucas1p1.samsung.com (unknown [182.198.249.206]) by mailout1.w1.samsung.com (KnoxPortal) with ESMTP id 20250708114524euoutp01870847cf3f6bff197513c816ae7e4437~QRBfidFFU2350923509euoutp01g for ; Tue, 8 Jul 2025 11:45:24 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout1.w1.samsung.com 20250708114524euoutp01870847cf3f6bff197513c816ae7e4437~QRBfidFFU2350923509euoutp01g DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1751975124; bh=1ym+ZPwSAJBlUJTRBRpHOrnxcWfoWCspHKNp3aF96Zc=; h=Date:Subject:To:Cc:From:In-Reply-To:References:From; b=hTSmuD7oMDEzit2qwO94PA3KuPM3t2VfPla+ZeQLlhsNzfaZcuY74yloqGgMlREzO CsGI/sYzA9Yc1mk5B7u3++o5ws1E5d1puriNBi3OjaJXBAd0aHxnL7ewrUPjNlgXd6 LV3oL4gOBjFPocvDRFQB7NcOwi5rH+2xd/RpiYis= Received: from eusmtip2.samsung.com (unknown [203.254.199.222]) by eucas1p2.samsung.com (KnoxPortal) with ESMTPA id 20250708114523eucas1p2d8771c6a0d017b9bb67a6528e7582617~QRBe5i9Re1494914949eucas1p2S; Tue, 8 Jul 2025 11:45:23 +0000 (GMT) Received: from [106.210.134.192] (unknown [106.210.134.192]) by eusmtip2.samsung.com (KnoxPortal) with ESMTPA id 20250708114521eusmtip2651e660db53304d0ed855a7d7f6ea665~QRBcy78Hv2034520345eusmtip2O; Tue, 8 Jul 2025 11:45:21 +0000 (GMT) Message-ID: <261f2417-78a9-45b8-bcec-7e36421a243c@samsung.com> Date: Tue, 8 Jul 2025 13:45:20 +0200 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/8] dma-mapping: migrate to physical address-based API To: Leon Romanovsky Cc: Christoph Hellwig , Jonathan Corbet , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Robin Murphy , Joerg Roedel , Will Deacon , "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , =?UTF-8?Q?Eugenio_P=C3=A9rez?= , Alexander Potapenko , Marco Elver , Dmitry Vyukov , Masami Hiramatsu , Mathieu Desnoyers , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , Andrew Morton , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, iommu@lists.linux.dev, virtualization@lists.linux.dev, kasan-dev@googlegroups.com, linux-trace-kernel@vger.kernel.org, linux-mm@kvack.org, Jason Gunthorpe Content-Language: en-US From: Marek Szyprowski In-Reply-To: <20250708110007.GF592765@unreal> Content-Transfer-Encoding: 8bit X-CMS-MailID: 20250708114523eucas1p2d8771c6a0d017b9bb67a6528e7582617 X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" X-RootMTR: 20250625131920eucas1p271b196cde042bd39ac08fb12beff5baf X-EPHeader: CA X-CMS-RootMailID: 20250625131920eucas1p271b196cde042bd39ac08fb12beff5baf References: <35df6f2a-0010-41fe-b490-f52693fe4778@samsung.com> <20250627170213.GL17401@unreal> <20250630133839.GA26981@lst.de> <69b177dc-c149-40d3-bbde-3f6bad0efd0e@samsung.com> <20250708110007.GF592765@unreal> On 08.07.2025 13:00, Leon Romanovsky wrote: > On Tue, Jul 08, 2025 at 12:27:09PM +0200, Marek Szyprowski wrote: >> On 30.06.2025 15:38, Christoph Hellwig wrote: >>> On Fri, Jun 27, 2025 at 08:02:13PM +0300, Leon Romanovsky wrote: >>>>> Thanks for this rework! I assume that the next step is to add map_phys >>>>> callback also to the dma_map_ops and teach various dma-mapping providers >>>>> to use it to avoid more phys-to-page-to-phys conversions. >>>> Probably Christoph will say yes, however I personally don't see any >>>> benefit in this. Maybe I wrong here, but all existing .map_page() >>>> implementation platforms don't support p2p anyway. They won't benefit >>>> from this such conversion. >>> I think that conversion should eventually happen, and rather sooner than >>> later. >> Agreed. >> >> Applied patches 1-7 to my dma-mapping-next branch. Let me know if one >> needs a stable branch with it. > Thanks a lot, I don't think that stable branch is needed. Realistically > speaking, my VFIO DMA work won't be merged this cycle, We are in -rc5, > it is complete rewrite from RFC version and touches pci-p2p code (to > remove dependency on struct page) in addition to VFIO, so it will take > time. > > Regarding, last patch (hmm), it will be great if you can take it. > We didn't touch anything in hmm.c this cycle and have no plans to send PR. > It can safely go through your tree. Okay, then I would like to get an explicit ack from Jérôme for this. >> Leon, it would be great if You could also prepare an incremental patch >> adding map_phys callback to the dma_maps_ops, so the individual >> arch-specific dma-mapping providers can be then converted (or simplified >> in many cases) too. > Sure, will do. Thanks! Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland