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 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.lore.kernel.org (Postfix) with ESMTPS id 1643ACA0EE9 for ; Sun, 17 Aug 2025 11:16:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=eUWODOYu7xl20YNi/5H7WavDXD5EiHAIElpuMjzztLk=; b=FPF6VkN+RgrXTCKmxM2/B01BRN QfyMMHPh2ZDFFqeBUtXQXwSOC1gkXcyjv5lbd/YJb/V4RpcmmuZBd530qAW6NIY4Y3HTymWgzkR+k 2TbtqrAGOzxe6I6XxLgPMhWPG4BdkKPCRtjlejLoSWyinPqZgRyMxGjO64y/HYt3oUZE6j2Ozox52 11ArYoy5Fzvfc3EOHelhhy6+NRG0W/wTUoYivERAaiB7J+i45vej/6EMGVGvkKG5O8VZfLp6PAP9B X1BqwPJELyFnXzN8oWaOn24NUYdQB4rGTUBQhHOlFG3Xjh6dA95JM0yt/mnz6jCdQewAZAvHU08k5 gW13yc0w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1unbNO-00000005aU1-2BwF; Sun, 17 Aug 2025 11:16:38 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1umcA4-00000000FUN-0hFo for linux-nvme@lists.infradead.org; Thu, 14 Aug 2025 17:54:49 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id AD63A5C721E; Thu, 14 Aug 2025 17:54:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8F749C4CEF6; Thu, 14 Aug 2025 17:54:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755194087; bh=6kQRc8M4kSTN6oNlv6UupesxmLI8KrU+a1TL4nhd0iE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=C6w4ugQYiUdcIBDBap/wpiQAIwZla3sL70dXT7fdDwlS8iAo7WkvllaYcXF4QU2M9 kt4WEnzYrIn4ZDZURbuikMUlP1Qp9CxkQOq+obTZHosuKzmVJJ0AF/lK9fQSX5YtoJ kzMxjlyIoIy5MaeVth9MfY0uS93UJW4vr922gEZKEo2egnsKAq7kg8ZgHQF2XBxqCZ F1uVGjeU46DFgcCqPy+lW15qydDCb2UvhK7t93bEVpZBLmZ+yVMS129GxQ41QBkFWL CFslA3zPU9Peu4BjTd3+d/0rvdaudAz+bJ7W9WzhuA5hIM9mliO10n+CPNH4ALRsGy OQQa8odedrzVg== From: Leon Romanovsky To: Marek Szyprowski Cc: Leon Romanovsky , Jason Gunthorpe , Abdiel Janulgue , Alexander Potapenko , Alex Gaynor , Andrew Morton , Christoph Hellwig , Danilo Krummrich , iommu@lists.linux.dev, Jason Wang , Jens Axboe , Joerg Roedel , Jonathan Corbet , Juergen Gross , kasan-dev@googlegroups.com, Keith Busch , linux-block@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-nvme@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-trace-kernel@vger.kernel.org, Madhavan Srinivasan , Masami Hiramatsu , Michael Ellerman , "Michael S. Tsirkin" , Miguel Ojeda , Robin Murphy , rust-for-linux@vger.kernel.org, Sagi Grimberg , Stefano Stabellini , Steven Rostedt , virtualization@lists.linux.dev, Will Deacon , xen-devel@lists.xenproject.org Subject: [PATCH v3 09/16] dma-mapping: handle MMIO flow in dma_map|unmap_page Date: Thu, 14 Aug 2025 20:54:00 +0300 Message-ID: X-Mailer: git-send-email 2.50.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250814_105448_282886_BEBF16F9 X-CRM114-Status: GOOD ( 14.42 ) X-Mailman-Approved-At: Sun, 17 Aug 2025 04:16:29 -0700 X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org From: Leon Romanovsky Extend base DMA page API to handle MMIO flow and follow existing dma_map_resource() implementation to rely on dma_map_direct() only to take DMA direct path. Signed-off-by: Leon Romanovsky --- kernel/dma/mapping.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index 891e1fc3e582..fdabfdaeff1d 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -158,6 +158,7 @@ dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, { const struct dma_map_ops *ops = get_dma_ops(dev); phys_addr_t phys = page_to_phys(page) + offset; + bool is_mmio = attrs & DMA_ATTR_MMIO; dma_addr_t addr; BUG_ON(!valid_dma_direction(dir)); @@ -166,14 +167,25 @@ dma_addr_t dma_map_page_attrs(struct device *dev, struct page *page, return DMA_MAPPING_ERROR; if (dma_map_direct(dev, ops) || - arch_dma_map_phys_direct(dev, phys + size)) + (!is_mmio && arch_dma_map_phys_direct(dev, phys + size))) addr = dma_direct_map_phys(dev, phys, size, dir, attrs); else if (use_dma_iommu(dev)) addr = iommu_dma_map_phys(dev, phys, size, dir, attrs); - else + else if (is_mmio) { + if (!ops->map_resource) + return DMA_MAPPING_ERROR; + + addr = ops->map_resource(dev, phys, size, dir, attrs); + } else { + /* + * The dma_ops API contract for ops->map_page() requires + * kmappable memory, while ops->map_resource() does not. + */ addr = ops->map_page(dev, page, offset, size, dir, attrs); + } - kmsan_handle_dma(phys, size, dir); + if (!is_mmio) + kmsan_handle_dma(phys, size, dir); trace_dma_map_phys(dev, phys, addr, size, dir, attrs); debug_dma_map_phys(dev, phys, size, dir, addr, attrs); @@ -185,14 +197,18 @@ void dma_unmap_page_attrs(struct device *dev, dma_addr_t addr, size_t size, enum dma_data_direction dir, unsigned long attrs) { const struct dma_map_ops *ops = get_dma_ops(dev); + bool is_mmio = attrs & DMA_ATTR_MMIO; BUG_ON(!valid_dma_direction(dir)); if (dma_map_direct(dev, ops) || - arch_dma_unmap_phys_direct(dev, addr + size)) + (!is_mmio && arch_dma_unmap_phys_direct(dev, addr + 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 + else if (is_mmio) { + if (ops->unmap_resource) + ops->unmap_resource(dev, addr, size, dir, attrs); + } else ops->unmap_page(dev, addr, size, dir, attrs); trace_dma_unmap_phys(dev, addr, size, dir, attrs); debug_dma_unmap_phys(dev, addr, size, dir); -- 2.50.1