From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-qk1-f180.google.com (mail-qk1-f180.google.com [209.85.222.180]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2E488288CA3 for ; Thu, 17 Jul 2025 13:44:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.222.180 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752759881; cv=none; b=BISMnMqqY35GVJwjrM2ICgQ6CgEZirxwWoBWrLpupCBvNhiKae9m75z8oxk1HbCRy23C4S8qSFJGEYIU5Y27orV1fNdkh1BFztNaurKzO2W7ChdsXGNQ4xj4PaJeZK0fMeOkLLe9bLMTBw6V9AfW+kwjEzKPqALjZRkJnfZfyI0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1752759881; c=relaxed/simple; bh=QbZfExTkz9ezd+mZoZd7gpecIGnudcaYo53khIW9w2Q=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=eZEmQ1K2LHA2yAW/54QSLpHueowHQqCkvHrHrMWlSrb99GFNDyUbGQF92fjjWnio/rf8i+XHR1nQpbHbbwREewy+NrpOjI2adJjYI5dEcg8H5IIvBrD5jdOd9WYRIKL9/KFjH51N9euIZduMopxDg6ajRjNl88W+yRv9je+HYAY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ziepe.ca; spf=pass smtp.mailfrom=ziepe.ca; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b=pIFL9/z1; arc=none smtp.client-ip=209.85.222.180 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ziepe.ca Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ziepe.ca Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="pIFL9/z1" Received: by mail-qk1-f180.google.com with SMTP id af79cd13be357-7dd8773f9d9so89652085a.2 for ; Thu, 17 Jul 2025 06:44:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; t=1752759877; x=1753364677; darn=lists.linux.dev; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=3h9H0emSy2YmRQohTbVQYplphXVxbD/CjutLsxOSDeU=; b=pIFL9/z1qQzv6UphFmw6/iJNLF9IeUwGYWpqrWhrKjHPiAoNEVFLnhfBUhTUNButyQ hPIRhFwd0oVpJxFkqKI7BxtxKNuCf3SdXSjmBEi4ZqsqvVmrpNCkis0wNrMmqtF2J1wI RcIRCPsZ9WsP9/LeOKfUqSd1l1m7rHVJD9GSjVB2nIBZBlzWoynvAcp8JZBMEvKICQdC JA7RaRXqrOOtelpTL36gpEn/IeLJpsOn9U5xv2lxnivTtSzP+NuuHATEw6+HaXpBtqy+ GXjHJBFDCw7L/CFY3h5GPwdn4kAh0c0PnzIoic5B5OPuZIxY0f+ItMgTY023X4Rtt0ES R4lw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1752759877; x=1753364677; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=3h9H0emSy2YmRQohTbVQYplphXVxbD/CjutLsxOSDeU=; b=DnKcSsKpdkvgysOT27zvafb2mfjdXPFox2Qdvj/dsZbvtAMR7erHwmmNy0tOmKg6qD snpJPVHtQ/sftdSQg/PODwGq8zMHM1VJD+DYX7i2ZfHv5p9sJCD9mU34mq9RPB1ONTVP iM//o65LDpuSoADpcX03D03RJ/DmBIssxSBjMVAWqsAXUd4+JVONO2jYQ9scFAqha9MO IxXLIhAjO8N2Y+Jq04EGJdphxhCHHQHnVJ3R0l6HX+hLt2DhebVKtboAFtbmQ6GX5ElC fDpinP778KAZf3AhrgXW/2fUMebIu+WnZ7HIn1Qa07+LcRK7cuT+CSRQVXmnZjsO3acN 7Rxw== X-Forwarded-Encrypted: i=1; AJvYcCWC1iGhkcPrHfrQlEYQx2o/FKrdd+FCeOId491brk+OgjUNAPNzdMv8O6N5lsSjzx4FysdSYA==@lists.linux.dev X-Gm-Message-State: AOJu0Yye0wlWbCtCIi3iW+k2ts81ptAnteA7FtjZBDrmwnHEcajGTPjz /FoBmh5NuhfZqmloA8m45rZ2YUfigI2DfrmSLJIp39Wqyed4eG/xajHbfTKXVjM/luE= X-Gm-Gg: ASbGncvihiX2dAOBLMbAO7sM2FrLCuQbNaCqxE2kO9ZFtTfhnyScR5UMf3zoq8W0UYi 252By+NAJdALuNoUgWeHJ94TpRvdeHt/NHFv91XnJRD8uoRHVfUeb3CeZk8L1dkM8OVL7kvErHI OfHjsC6sF/jBKA3fvRgyKEGvL4R/pJMJggBbmyki3NfRy12gYL/7TxC1QXA2f5TF2nbi9WgHQhe tw+GBomL6eeL523khvweppcqUw26nhyI24Om24bfeFUdIpMj0PDvhg1ohAPdV7UENcIyxSlQYtg d4o+7H7vKTLPzSNEdPXZ0mw2Km9MahjzQ+48+oJY7IzJKUhvuXkqZUOLERkhysV2zDzvr4SwZ4T mc/qqTXDHbfwwnbPDy7gqbIbHkGN44Zq+fXoCB/ZCFTvZbHcJlKM9pv90jDtGSo5sRNLrdHL9JA == X-Google-Smtp-Source: AGHT+IGDySyig+wWvAUuDQJGxMS8KXMFfTxwUEZTDW4+kj+RafshaW2e2oWb5NZaiLXcI0d4QCUI2g== X-Received: by 2002:a05:620a:84c9:b0:7e1:8e73:b92 with SMTP id af79cd13be357-7e342b445admr1017048085a.36.1752759876748; Thu, 17 Jul 2025 06:44:36 -0700 (PDT) Received: from ziepe.ca (hlfxns017vw-142-167-56-70.dhcp-dynamic.fibreop.ns.bellaliant.net. [142.167.56.70]) by smtp.gmail.com with ESMTPSA id af79cd13be357-7e334178dc8sm414280585a.8.2025.07.17.06.44.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Jul 2025 06:44:35 -0700 (PDT) Received: from jgg by wakko with local (Exim 4.97) (envelope-from ) id 1ucOuZ-00000009GbK-0ypM; Thu, 17 Jul 2025 10:44:35 -0300 Date: Thu, 17 Jul 2025 10:44:35 -0300 From: Jason Gunthorpe To: Leon Romanovsky Cc: Marek Szyprowski , Leon Romanovsky , iommu@lists.linux.dev Subject: Re: [PATCH 1/2] dma-mapping: prepare dma_map_ops to conversion to physical address Message-ID: <20250717134435.GA2206214@ziepe.ca> References: <1798a3351dcabccaf0749221e9e9b66585a7b2c6.1752734252.git.leon@kernel.org> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1798a3351dcabccaf0749221e9e9b66585a7b2c6.1752734252.git.leon@kernel.org> On Thu, Jul 17, 2025 at 09:47:09AM +0300, Leon Romanovsky wrote: > @@ -183,7 +187,11 @@ dma_addr_t dma_map_phys(struct device *dev, phys_addr_t phys, size_t size, > * All platforms which implement .map_page() don't support > * non-struct page backed addresses. > */ > - addr = ops->map_page(dev, page, offset, size, dir, attrs); > + if (ops->map_phys) > + addr = ops->map_phys(dev, phys, size, dir, attrs); > + if (ops->map_page) > + addr = ops->map_page(dev, page, offset, size, dir, > + attrs); I would expect 'else if' > @@ -213,8 +221,16 @@ void dma_unmap_phys(struct device *dev, dma_addr_t addr, size_t size, > dma_direct_unmap_phys(dev, addr, size, dir, attrs); > else if (use_dma_iommu(dev)) > iommu_dma_unmap_phys(dev, addr, size, dir, attrs); > - else > - ops->unmap_page(dev, addr, size, dir, attrs); > + else { > + if (IS_ENABLED(CONFIG_DMA_API_DEBUG)) > + /* We shouldn't have both functions */ > + WARN_ON_ONCE(ops->unmap_page && ops->unmap_phys); > + > + if (ops->unmap_phys) > + ops->unmap_phys(dev, addr, size, dir, attrs); > + if (ops->unmap_page) > + ops->unmap_page(dev, addr, size, dir, attrs); Here too What is the practical difference between unmap_phys and unmap_page? Do we expect implementations of map/unmap phys to never touch the struct page? I see a few cases of dma_ops that are doing this, eg for cache flushing so they won't be converted? If not, how are the ops supposed to know if a KVA is available or not for the phys argument? Jason