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 D8C5A2D320E for ; Mon, 11 Aug 2025 13:30:55 +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=1754919055; cv=none; b=nsOiXrks6vVh/qA+7HELj88JaIQpcsirS+EZYy8JKdz28vY4Zi8oFxB1X/RyxbDLP6TpS7F0vZOqGyazyI3GilfRKwUdc/p9KzRGM8iHzY/wUn5ehhx0bQT9MVqkFOmQQF/NtBCjoNtSQZ/SWnIBcaTvWCNNf/O4HmS42H82AXw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754919055; c=relaxed/simple; bh=wZjCh8XlQL32DPQm8fd7YqWZa/4AL5hrwFmnrWSDD78=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=p/Q2/f1pCKMDzNq5RNbd+asXaUzRhXpPbr8ChVa0RdZ5WjAnYi9oPhOA4se3DQnoc0XfJQTc1Rb9DxJYg+EVyHGE83LQQdwL1AjJCEnPoMVPYQI48Ta3y1IIgExzhSUGjGSD2z/mjyPTuilhIbdlMoFWQipgFH2xiWH6yKATE3Q= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=jZJra/xF; 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="jZJra/xF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D89B2C4CEED; Mon, 11 Aug 2025 13:30:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1754919055; bh=wZjCh8XlQL32DPQm8fd7YqWZa/4AL5hrwFmnrWSDD78=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=jZJra/xFTZZUYA2ye35yT03O3yRf7zdbDk/qD0SUM10HA/zsiMhXFXL+GmwH0xUWC nUX94uoMGxW7dw+UefsARCMkdmxgpaw/b92IlU6bbVlPm3VIE9VMao1Dzwf1iMh2tI UWs4KBLOOHZyVjAbHjrdHZNihbkFMV4bv2W0eZiswFxD1P9fOJY+7inG0FJW92ncdR n1CJeXqVNldYBJwfEqK8SolLz8A0M/cfdXUMVt62b+o/IOOGNLrSEamrv2ydlh1KWT QSChZwmrAODvtk2q0WZ/xSEkpct8bsxJpdwlAf2PBD5Yt1U6I4G4mEgUsqyPiGzTsF Mbe6QbADDF9Og== Date: Mon, 11 Aug 2025 07:30:53 -0600 From: Keith Busch To: Christoph Hellwig Cc: Keith Busch , linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, axboe@kernel.dk, joshi.k@samsung.com Subject: Re: [PATCHv5 1/8] blk-mq-dma: introduce blk_map_iter Message-ID: References: <20250808155826.1864803-1-kbusch@meta.com> <20250808155826.1864803-2-kbusch@meta.com> <20250810140448.GA4262@lst.de> Precedence: bulk X-Mailing-List: linux-block@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: <20250810140448.GA4262@lst.de> On Sun, Aug 10, 2025 at 04:04:48PM +0200, Christoph Hellwig wrote: > > +struct blk_map_iter { > > + phys_addr_t paddr; > > + u32 len; > > + struct bvec_iter iter; > > + struct bio *bio; > > +}; > > This now mixes the output previous in the phys_vec, and instead > of keeping it private to the implementation exposes it to all the > callers. I could not find an explanation in the commit log, nor > something that makes use of it later in the series. > > If possible I'd like to keep these separate and the output isolated > in blk-mq-dma.c. But if there's a good reason to merge them, please > add it to the commit log, and also clearly document the usage of the > fields in the (public) structure. Especially the len member could > very easily confuse. Perhaps I misunderstood the assignment: https://lore.kernel.org/linux-block/20250722055339.GB13634@lst.de/ I thought you were saying you wanted the lower (bvec pages -> phys addrs) and upper part (phys -> dma) available as an API rather than keeping the lower part private to blk-dma. This patch helps move towards that, and in the next patch provides a common place to stash the bvec array that's being iterated.