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 B236E30C375; Tue, 19 Aug 2025 17:38:36 +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=1755625116; cv=none; b=e2P+3kDTJD3GQhAsrSiD76BUVm2UzUlWBVjU6qVHsa7Gyz/87XSwWkiV2IcCbhEK7jQ2ts2L0UG5uJ6c+GHkX1Jlg5IcQPhDyxFAFONlrqGpjiu5G7AYB5QO9LQYWTFHl9Uc9eiNbg6QBDOTW9OWTmiJUKBZIUZBm+EwxBZkUwI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755625116; c=relaxed/simple; bh=O9XZOHlHvjORXmOt4kTIQrFLHTrONFqw1ae8lUbcYw8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=GlgjwqtZdUdHzHkgSTrfFAg3B2xufJINJYzVfVMJeIyg/xLDmVvzSqr17O/oYt6gMCWcRtiBZO5RXm14sEo5oQMifY/iB6+JHxidUPV1tnFLUaEzDmzeCQDPUVy0N0e5/U1pktqgyXVLxI2Fd83r8EACWhTcWMcEbXLaizqnM/g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ATZH+tt0; 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="ATZH+tt0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9165BC4CEF1; Tue, 19 Aug 2025 17:38:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755625116; bh=O9XZOHlHvjORXmOt4kTIQrFLHTrONFqw1ae8lUbcYw8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ATZH+tt0E0CIypcrTSNKTLVbz11CKQWPuWVv8Uj9hFXpVu8WhMldVqGJubdEEOKA5 ihrhveF/7PK4ciLaP1743VsR6NY/mkFLhxNufmCXwfsaz906MGNVzEujW1yZCGg7UJ V0f9Op2bM/LDCmIDoTw89nki6nqBzfilToxhqaVR8w0WmvQL8B8EY2oxWuG20cX/6j TL1fryJQsGuMrJZkOQ1NbVtcj71sbARhi2TXWmqIIZ9BTi18mEhP8usOCf32R7gnLD uaTJdR9D9iuPFRWq/Gj2stVOJgLdUiBmlsVIk3TNaKhBqMgGSVJIQ5h9MDirkdjHNx bZTvCl5dJvTcQ== 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 v4 12/16] mm/hmm: migrate to physical address-based DMA mapping API Date: Tue, 19 Aug 2025 20:36:56 +0300 Message-ID: <18165db0ff83f8222bfd05c4807cda206bec02f7.1755624249.git.leon@kernel.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Leon Romanovsky Convert HMM DMA operations from the legacy page-based API to the new physical address-based dma_map_phys() and dma_unmap_phys() functions. This demonstrates the preferred approach for new code that should use physical addresses directly rather than page+offset parameters. The change replaces dma_map_page() and dma_unmap_page() calls with dma_map_phys() and dma_unmap_phys() respectively, using the physical address that was already available in the code. This eliminates the redundant page-to-physical address conversion and aligns with the DMA subsystem's move toward physical address-centric interfaces. This serves as an example of how new code should be written to leverage the more efficient physical address API, which provides cleaner interfaces for drivers that already have access to physical addresses. Reviewed-by: Jason Gunthorpe Signed-off-by: Leon Romanovsky --- mm/hmm.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/mm/hmm.c b/mm/hmm.c index d545e2494994..015ab243f081 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -775,8 +775,8 @@ dma_addr_t hmm_dma_map_pfn(struct device *dev, struct hmm_dma_map *map, if (WARN_ON_ONCE(dma_need_unmap(dev) && !dma_addrs)) goto error; - dma_addr = dma_map_page(dev, page, 0, map->dma_entry_size, - DMA_BIDIRECTIONAL); + dma_addr = dma_map_phys(dev, paddr, map->dma_entry_size, + DMA_BIDIRECTIONAL, 0); if (dma_mapping_error(dev, dma_addr)) goto error; @@ -819,8 +819,8 @@ bool hmm_dma_unmap_pfn(struct device *dev, struct hmm_dma_map *map, size_t idx) dma_iova_unlink(dev, state, idx * map->dma_entry_size, map->dma_entry_size, DMA_BIDIRECTIONAL, attrs); } else if (dma_need_unmap(dev)) - dma_unmap_page(dev, dma_addrs[idx], map->dma_entry_size, - DMA_BIDIRECTIONAL); + dma_unmap_phys(dev, dma_addrs[idx], map->dma_entry_size, + DMA_BIDIRECTIONAL, 0); pfns[idx] &= ~(HMM_PFN_DMA_MAPPED | HMM_PFN_P2PDMA | HMM_PFN_P2PDMA_BUS); -- 2.50.1