From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from cmx-mtlrgo002.bell.net (mta-mtl-006.bell.net [209.71.208.28]) (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 8885723AB8B; Fri, 3 Oct 2025 17:23:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.71.208.28 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759512211; cv=none; b=KRrVSQ5niMyPZiZgdbvLTVKsi2q/BIi3YJUOE5TRV/yN6DgLenjq4CdfKJkzbFbWOqKaIL0QwMm6Zfg5v0nXv2QfRGBWQ4HG+EpKQhuePDtGIq0H8+vVc/Opkye7OriDvP8bKFc4+9iGj8k3BLA1i8F4EGNSotiyCeNtdorHwpk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759512211; c=relaxed/simple; bh=Di4WMImwmV6KHePb6cCCkczkHfQ+nxD1+liCaEC8/NM=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=t2P4PYl+XgIT7wGYDlN2ZUEpyqYCZkrBJ0hM1aUyOJSDNkbfdzX8tJ8JFnBA1vR6lK2zUSlBkB3L/Xdebkumvft5q+PbvTEZwtXAK0Yx9TM9j9EQcbO/pZt4fZSwiqdPKvsJFL73uVI06uy/PbZOwvgdc5YCbLztqe8z0xpWHvs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=bell.net; spf=pass smtp.mailfrom=bell.net; dkim=pass (2048-bit key) header.d=bell.net header.i=@bell.net header.b=STH7xa2d; arc=none smtp.client-ip=209.71.208.28 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=bell.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bell.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bell.net header.i=@bell.net header.b="STH7xa2d" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bell.net; s=selector1; t=1759512209; bh=Zng9vbugJ96jo23SWsSK+sYWjXU4T6lDUgmXQbXs8jQ=; h=Message-ID:Date:MIME-Version:Subject:To:References:From:In-Reply-To:Content-Type; b=STH7xa2dn/qPmG92jIcX/GRtDkY0RNMiWnaUX5nw4Z/94xFcZXc3uJksIGEjcy+vM8yrxb27s1Lk8snvVVHgaMQbkjzCZNKE3nbg+KtIVyDN4KsoYPof2Atingxuln/n03japvC+xNiLOlEtSJtyGmtnQUGfNPTraDKPtHf6YNklzHvlwd9iK8TXMtJwjxQXrdccJ8vPzzVLXKrV4pyz01fTUXQk87j7gvz/6R55jp8AvnIUUElARVMUsqK7UbjZ/tPWcKj340Wvf9pk/6ausvqT2/bEEC1xRZLlW/zTejBCGHL6POoP6FGPT9dP7GmyqcpIXCwML+3eoUgkas19yw== X-RG-SOPHOS: Clean X-RG-VADE-SC: 0 X-RG-VADE: Clean X-RG-Env-Sender: dave.anglin@bell.net X-RG-Rigid: 687D2719085236A8 X-RazorGate-Vade: 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 X-RazorGate-Vade-Verdict: clean 0 X-RazorGate-Vade-Classification: clean Received: from [192.168.2.49] (142.126.189.246) by cmx-mtlrgo002.bell.net (authenticated as dave.anglin@bell.net) id 687D2719085236A8; Fri, 3 Oct 2025 13:18:32 -0400 Message-ID: <610b10bc-1aa2-4fad-a40b-be5fcfa04430@bell.net> Date: Fri, 3 Oct 2025 13:18:32 -0400 Precedence: bulk X-Mailing-List: linux-mips@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1 3/9] parisc: Convert DMA map_page to map_phys interface To: Jason Gunthorpe , Leon Romanovsky Cc: Marek Szyprowski , Leon Romanovsky , Andreas Larsson , Borislav Petkov , Dave Hansen , "David S. Miller" , Geoff Levand , Helge Deller , Ingo Molnar , iommu@lists.linux.dev, "James E.J. Bottomley" , Jason Wang , Juergen Gross , linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Madhavan Srinivasan , Matt Turner , Michael Ellerman , "Michael S. Tsirkin" , Richard Henderson , sparclinux@vger.kernel.org, Stefano Stabellini , Thomas Bogendoerfer , Thomas Gleixner , virtualization@lists.linux.dev, x86@kernel.org, xen-devel@lists.xenproject.org, Magnus Lindholm References: <333ec4dabec16d3d913a93780bc6e7ddb5240fcf.1759071169.git.leon@kernel.org> <20251003150144.GC3360665@nvidia.com> From: John David Anglin Content-Language: en-US Autocrypt: addr=dave.anglin@bell.net; keydata= xsFNBFJfN1MBEACxBrfJ+5RdCO+UQOUARQLSsnVewkvmNlJRgykqJkkI5BjO2hhScE+MHoTK MoAeKwoLfBwltwoohH5RKxDSAIWajTY5BtkJBT23y0hm37fN2JXHGS4PwwgHTSz63cu5N1MK n8DZ3xbXFmqKtyaWRwdA40dy11UfI4xzX/qWR3llW5lp6ERdsDDGHm5u/xwXdjrAilPDk/av d9WmA4s7TvM/DY3/GCJyNp0aJPcLShU2+1JgBxC6NO6oImVwW07Ico89ETcyaQtlXuGeXYTK UoKdEHQsRf669vwcV5XbmQ6qhur7QYTlOOIdDT+8zmBSlqBLLe09soATDciJnyyXDO1Nf/hZ gcI3lFX86i8Fm7lQvp2oM5tLsODZUTWVT1qAFkHCOJknVwqRZ8MfOvaTE7L9hzQ9QKgIKrSE FRgf+gs1t1vQMRHkIxVWb730C0TGiMGNn2oRUV5O5QEdb/tnH0Te1l+hX540adKZ8/CWzzW9 vcx+qD9IWLRyZMsM9JnmAIvYv06+YIcdpbRYOngWPd2BqvktzIs9mC4n9oU6WmUhBIaGOGnt t/49bTRtJznqm/lgqxtE2NliJN79dbZJuJWe5HkjVa7mP4xtsG59Rh2hat9ByUfROOfoZ0dS sVHF/N6NLWcf44trK9HZdT/wUeftEWtMV9WqxIwsA4cgSHFR2QARAQABzTdKb2huIERhdmlk IEFuZ2xpbiAoRGViaWFuIFBvcnRzKSA8ZGF2ZS5hbmdsaW5AYmVsbC5uZXQ+wsF3BBMBCAAh BQJSXzdTAhsDBQsJCAcDBRUKCQgLBRYCAwEAAh4BAheAAAoJEF2/za5fGU3xs/4P/15sNizR ukZLNYoeGAd6keRtNcEcVGEpRgzc/WYlXCRTEjRknMvmCu9z13z8qB9Y9N4JrPdp+NQj5HEs ODPI+1w1Mjj9R2VZ1v7suFwhjxMTUQUjCsgna1H+zW/UFsrL5ERX2G3aUKlVdYmSWapeGeFL xSMPzawPEDsbWzBzYLSHUOZexMAxoJYWnpN9JceEcGvK1SU2AaGkhomFoPfEf7Ql1u3Pgzie ClWEr2QHl+Ku1xW0qx5OLKHxntaQiu30wKHBcsF0Zx2uVGYoINJl/syazfZyKTdbmJnEYyNa Bdbn7B8jIkVCShLOWJ8AQGX/XiOoL/oE9pSZ60+MBO9qd18TGYByj0X2PvH+OyQGul5zYM7Q 7lT97PEzh8xnib49zJVVrKDdJds/rxFwkcHdeppRkxJH0+4T0GnU2IZsEkvpRQNJAEDmEE8n uRfssr7RudZQQwaBugUGaoouVyFxzCxdpSYL6zWHA51VojvJYEBQDuFNlUCqet9LtNlLKx2z CAKmUPTaDwPcS3uOywOW7WZrAGva1kz9lzxZ+GAwgh38HAFqQT8DQvW8jnBBG4m4q7lbaum3 znERv7kcfKWoWS7fzxLNTIitrbpYA3E7Zl9D2pDV3v55ZQcO/M35K9teRo6glrtFDU/HXM+r ABbh8u9UnADbPmJr9nb7J0tZUSS/zsFNBFJfN1MBEADBzhVn4XyGkPAaFbLPcMUfwcIgvvPF UsLi9Q53H/F00cf7BkMY40gLEXvsvdUjAFyfas6z89gzVoTUx3HXkJTIDTiPuUc1TOdUpGYP hlftgU+UqW5O8MMvKM8gx5qn64DU0UFcS+7/CQrKOJmzktr/72g98nVznf5VGysa44cgYeoA v1HuEoqGO9taA3Io1KcGrzr9cAZtlpwj/tcUJlc6H5mqPHn2EdWYmJeGvNnFtxd0qJDmxp5e YVe4HFNjUwsb3oJekIUopDksAP41RRV0FM/2XaPatkNlTZR2krIVq2YNr0dMU8MbMPxGHnI9 b0GUI+T/EZYeFsbx3eRqjv1rnNg2A6kPRQpn8dN3BKhTR5CA7E/cs+4kTmV76aHpW8m/NmTc t7KNrkMKfi+luhU2P/sKh7Xqfbcs7txOWB2V4/sbco00PPxWr20JCA5hYidaKGyQxuXdPUlQ Qja4WJFnAtBhh3Oajgwhbvd6S79tz1acjNXZ89b8IN7yDm9sQ+4LhWoUQhB5EEUUUVQTrzYS yTGN1YTTO5IUU5UJHb5WGMnSPLLArASctOE01/FYnnOGeU+GFIeQp91p+Jhd07hUr6KWYeJY OgEmu+K8SyjfggCWdo8aGy0H3Yr0YzaHeK2HrfC3eZcUuo+yDW3tnrNwM1rd1i3F3+zJK18q GnBxEQARAQABwsFfBBgBCAAJBQJSXzdTAhsMAAoJEF2/za5fGU3xNDQP/ikzh1NK/UBrWtpN yXLbype4k5/zyQd9FIBxAOYEOogfKdkp+Yc66qNf36gO6vsokxsDXU9me1n8tFoB/DCdzKbQ /RjKQRMNNR4fT2Q9XV6GZYSL/P2A1wzDW06tEI+u+1dV40ciQULQ3ZH4idBW3LdN+nloQf/C qoYkOf4WoLyhSzW7xdNPZqiJCAdcz9djN79FOz8US+waBCJrL6q5dFSvvsYj6PoPJkCgXhiJ hI91/ERMuK9oA1oaBxCvuObBPiFlBDNXZCwmUk6qzLDjfZ3wdiZCxc5g7d2e2taBZw/MsKFc k+m6bN5+Hi1lkmZEP0L4MD6zcPuOjHmYYzX4XfQ61lQ8c4ztXp5cKkrvaMuN/bD57HJ6Y73Q Y+wVxs9x7srl4iRnbulCeiSOAqHmwBAoWaolthqe7EYL4d2+CjPCcfIuK7ezsEm8c3o3EqC4 /UpL1nTi0rknRTGc0VmPef+IqQUj33GGj5JRzVJZPnYyCx8sCb35Lhs6X8ggpsafUkuKrH76 XV2KRzaE359RgbM3pNEViXp3NclPYmeu+XI8Ls/y6tSq5e/o/egktdyJj+xvAj9ZS18b10Jp e67qK8wZC/+N7LGON05VcLrdZ+FXuEEojJWbabF6rJGN5X/UlH5OowVFEMhD9s31tciAvBwy T70V9SSrl2hiw38vRzsl In-Reply-To: <20251003150144.GC3360665@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 2025-10-03 11:01 a.m., Jason Gunthorpe wrote: > This doesn't actually use the virt at all: > > offset = ((unsigned long) addr) & ~IOVP_MASK; > if((size % L1_CACHE_BYTES) || ((unsigned long)addr % L1_CACHE_BYTES)) > ccio_io_pdir_entry(pdir_start, KERNEL_SPACE, (unsigned long)addr, hint); > > And ccio_io_pdir_entry(): > pa = lpa(vba); > > Is a special instruction that uses virt but AI tells me that special > LPA instruction is returning phys. Not sure if that is a different > value than virt_to_phys().. ccio_io_pdir_entry currently only supports KERNEL_SPACE. For KERNEL_SPACE, lpa() and virt_to_phys() are equivalent if page is mapped. lpa() returns 0 if a non-access data TLB fault occurs (i.e., page isn't mapped). Not sure if that matters. > IDK, I'm not feeling brave enough to drop the LPA but maybe include > this note in the commit message. > -- John David Anglin dave.anglin@bell.net