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 DDB401F427D; Wed, 30 Oct 2024 14:57:54 +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=1730300277; cv=none; b=dbHkslTiAgf7WT0W5XftOeQGHOLVFqSHjMwM2QEemqHZZzc+Hy+VhovyeAEiSEEatdoRsCt9dGdwFn0LK0B+RTr5Npco2s4XrSSAs3aROimUvznxAg2f9/9xIXM7XXwR5MkPLqCv/yQsoSbFGbxslFsohyNuA4tsQEBxeGsQvMI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730300277; c=relaxed/simple; bh=mefuM4t1ECqbl3fiXwjneiO0N0zCuMcAR7sLOr/5iEg=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=mYlAtRxYJq30NVk0ozr6/9tkZPtDUHXd3ePaYErdcB/k7G0aRkE5QKRny3RkLMRHSY/hRrbjCvBcK2ZQaQK60lcvsi2EwqIWR4aRBsuwkFqkL8hb/gx+2wGgPKSJk7864VrAFP0V4rKKIB5B28mKcCpQPVhi1iF+sF+4HhXKw5o= 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=OTLoqjE1; 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="OTLoqjE1" 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=EOhe37wzhw7xzeIak4/ImqmXuzFb2P7wAz173iN/p4U=; b=OTLoqjE1CZqI8ShDmv6JW4Ktxv hMRcPCrHHuu3B0qZfUNGiu9RW+3TpKco6Fmrg5szaBTrgFlqAQHcM4mWnn2QfL7M8uXM8F9Zhw4dB SkugKclQ8gBVH2xCldCkVnlZIsbRBC9Rt5+Md/5MwEGL28yyG6znlZuObJdb3QATdExFcwJTedoeS U3AJjnwNVpfZufyQ1NYkXFQmGtcN5WuSt741wtZvdZxtjWqJ/9KjRcwyUWrxbgBSuPwU0mRTGCORi CkH50ekY9Ok5BwMMHY8Fc4mLDvSyGgkjsqHZdrbRnyQ2qUvzown8yZzFMp+yI8lTIwiRDhfkjmyEI 25loAEPw==; Received: from hch by bombadil.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1t6A8v-00000000kGb-1hC0; Wed, 30 Oct 2024 14:57:53 +0000 Date: Wed, 30 Oct 2024 07:57:53 -0700 From: Christoph Hellwig To: Pavel Begunkov Cc: Christoph Hellwig , David Wei , io-uring@vger.kernel.org, netdev@vger.kernel.org, Jens Axboe , Jakub Kicinski , Paolo Abeni , "David S. Miller" , Eric Dumazet , Jesper Dangaard Brouer , David Ahern , Mina Almasry , Stanislav Fomichev , Joe Damato , Pedro Tammela , Sumit Semwal , Christian =?iso-8859-1?Q?K=F6nig?= , linux-media@vger.kernel.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org Subject: Re: [PATCH v6 02/15] net: generalise net_iov chunk owners Message-ID: References: <20241016185252.3746190-1-dw@davidwei.uk> <20241016185252.3746190-3-dw@davidwei.uk> <264c8f95-2a69-4d49-8af6-d035fa890ef1@gmail.com> <9a14e132-6a13-4077-973d-b1eca417e563@gmail.com> Precedence: bulk X-Mailing-List: io-uring@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: <9a14e132-6a13-4077-973d-b1eca417e563@gmail.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Tue, Oct 29, 2024 at 04:35:16PM +0000, Pavel Begunkov wrote: > I see, the reply is about your phrase about additional memory > abstractions: > > "... don't really need to build memory buffer abstraction over > memory buffer abstraction." Yes, over the exsting memory buffer abstraction (dma_buf). > If you mean internals, making up a dmabuf that has never existed in the > picture in the first place is not cleaner or easier in any way. If that > changes, e.g. there is more code to reuse in the future, we can unify it > then. I'm not sure what "making up" means here, they are all made up :) > > with pre-registering the memry with the iommu to get good performance > > in IOMMU-enabled setups. > > The page pool already does that just like it handles the normal > path without providers. In which case is basically is a dma-buf. If you'd expose it as such we could actually use to communicate between subsystems in the kernel.