From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id B14BBC54ED1 for ; Sat, 28 Jun 2025 18:59:40 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 56B036B00A3; Sat, 28 Jun 2025 14:59:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 5427D6B00A4; Sat, 28 Jun 2025 14:59:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 47FF26B00A5; Sat, 28 Jun 2025 14:59:40 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 349DD6B00A3 for ; Sat, 28 Jun 2025 14:59:40 -0400 (EDT) Received: from smtpin29.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id ACCAA105CFD for ; Sat, 28 Jun 2025 18:59:39 +0000 (UTC) X-FDA: 83605723278.29.9F0731F Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf10.hostedemail.com (Postfix) with ESMTP id 06720C0005 for ; Sat, 28 Jun 2025 18:59:37 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=K2snykvp ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1751137178; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=+V31Sb7lyUAetps5kXX6jaGXqJOXR4iB8FLG9YZKZb8=; b=i8D4QfwoM6GhYLGabem00Ft1GKggB8hHQfN2+sditrljA+qIh0PYlK+Uc4yGzS9NIj7y7s 5j6Fi87TyrcEvRC1/IL/6KDW4+C6gxXNQmaWy1FgagvrPSYwjehGPSTeb2hL5xajFs2wz4 J2xQyKem+2TgR+7w4uNzg21WLz5s6LA= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=K2snykvp; spf=none (imf10.hostedemail.com: domain of rdunlap@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=rdunlap@infradead.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1751137178; a=rsa-sha256; cv=none; b=uR9S/BoL5hnuC500UydAWyGWOmrF7oo6ViC9FewNSX/QCWbs84eF3imnzt3iEvtN1WCNxo md798fxt0Y/oseSNWKo1MCyKUm1QcRV9RC/7tKJiGvqXM4PBQ1++ip5TfIL2ECC/CXsYHL czNnNQkgc40mHAOWkBv8a9JCTWU5w18= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=Content-Transfer-Encoding:Content-Type: In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date:Message-ID:Sender :Reply-To:Content-ID:Content-Description; bh=+V31Sb7lyUAetps5kXX6jaGXqJOXR4iB8FLG9YZKZb8=; b=K2snykvpAxbQdQbj1t5VH3C8M5 QKrHoblJGRl9vbFcaNpCOUEjUhNlAlePRanLo21WEmOzE1Mmwa40wTKewY0dPifJMQssiH9a5Hsk0 qcLYqjSQr/QCTNXnEnX6SFLG+Vzp1Ff23b1k5bkMB/R6p+ocVf6OykwONFAvLyfdrV+ZU52NfWR/6 zCah8vs9vGUniDV6wmpjcugntvNGB57qyl+e245jjgKZBbUYc7SLMi41Oqot0VSuhADNWR5z3hztr h/lPswLUh4efaIzJD5es/IWOK24EWYo7YVnU0+AsYCR5x1VDjs7NeEhLD2ppjJ78FWOJdm9LEujYc kUD8+55Q==; Received: from [50.53.25.54] (helo=[192.168.254.17]) by casper.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1uValy-0000000H7yS-22SC; Sat, 28 Jun 2025 18:59:34 +0000 Message-ID: <337ea10d-d6b6-496e-b1e3-4ee912067e8e@infradead.org> Date: Sat, 28 Jun 2025 11:59:31 -0700 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 7/8] docs: dma-api: update streaming DMA physical address constraints To: Petr Tesarik , Jonathan Corbet , Robin Murphy , Marek Szyprowski Cc: Andrew Morton , Keith Busch , Jens Axboe , Bagas Sanjaya , "open list:DOCUMENTATION" , open list , "open list:MEMORY MANAGEMENT" , iommu@lists.linux.dev References: <20250627101015.1600042-1-ptesarik@suse.com> <20250627101015.1600042-8-ptesarik@suse.com> Content-Language: en-US From: Randy Dunlap In-Reply-To: <20250627101015.1600042-8-ptesarik@suse.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 06720C0005 X-Stat-Signature: fkeqe7s4hijz1ifhahoghjc4fmo3sjc5 X-Rspam-User: X-HE-Tag: 1751137177-665268 X-HE-Meta: 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 yem/AuQr nl8ufnQta7CsDXlP8eedQ9pSClti6+BB+SUOoY3dhg2RtdAafGNmVMRr/65r8XaWfs2QGGSlJfeBNkY4pRcae9TIEmFdsQ575bS6EG5AcuHT4QRVn3VMRW+PLus+5Jd6Iyi50uI91dgg5p9j8GUqzhZwfrcNTl7Ke5yFVHUc+wE3jZoTwlH0ulmKLL+4QXdX0zHUw4Y01+7RLiA+jx12DarNm3f3WVPRGSkzOHZqCABN/ESS32Q/sk5OH2jmG6mPpxqUa3Bdxhz/WO5vTBlaPKmqvBh/6z2kvGidOHXb4Tuh9CP45OahQ3Hb0lMY01khtZQTD0Gw3g+06wxrXOguX8uSxuw== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 6/27/25 3:10 AM, Petr Tesarik wrote: > Add an introductory paragraph to Part Id - Streaming DMA mappings and move > the explanation of address constraints there, because it applies to all map > functions. > > Clarify that streaming DMA can be used with memory which does not meet the > addressing constraints of a device, but it may fail in that case. > > Make a note about SWIOTLB and link to the detailed description of it. > > Do not mention platform-dependent allocation flags. The note may mislead > device driver authors into thinking that they should poke into and try to > second-guess the DMA API implementation. They definitely shouldn't. > > Remove the claim that platforms with an IOMMU may not require physically > contiguous buffers. The current implementation explicitly rejects vmalloc > addresses, regardless of IOMMU. > > Signed-off-by: Petr Tesarik Tested-by: Randy Dunlap Thanks. > --- > Documentation/core-api/dma-api.rst | 36 +++++++++++++++++------------- > 1 file changed, 21 insertions(+), 15 deletions(-) -- ~Randy