From nobody Fri Oct 3 11:25:37 2025 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 6A897340DAA; Tue, 2 Sep 2025 14:49:53 +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=1756824593; cv=none; b=b9mW/HziFgXqbd0YX7ArmAqBrJ9ze9lka7ou543+K03FOCvF8LzsKzt91Z9PeOYQm0ixgYGA3v1/iYesfbqvD3cbT20tNPa2wdeCHPTVmBXhB4jmb2hQcF9iwWcDolHeW8wvx5xTDANHUvcJ82of35nAXAyvKjl7bJcheiEaxAY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756824593; c=relaxed/simple; bh=O9XZOHlHvjORXmOt4kTIQrFLHTrONFqw1ae8lUbcYw8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=AeIIeZPrHi4gLzVIydSBh7gydiwPokCgxkPhcg0lfvv1aA2FhLUTbtYdYf0L9uxeA8cW0vyU8qR3CglnnStdQyXYLPmrjzn0jDzOW4Zq7Hhn4eGgE7WOrQqB01APkNVySdN513Or8Bm0lnpQvSHF8tn0Z+GnXzV/WPftq4fbYN0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=i4LP/8sF; 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="i4LP/8sF" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7E5E9C4CEED; Tue, 2 Sep 2025 14:49:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756824593; bh=O9XZOHlHvjORXmOt4kTIQrFLHTrONFqw1ae8lUbcYw8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=i4LP/8sFn4GJsZ/wYwZJG+51+koOumcx5kwuswjw9uzDtXu5nJFVYiFdkD5Pd0XDV CJojBBl/IcJFZ1DnDDaW5/OvJIPqgpfNaVsr+q2jlXPVvC5bdwVF7QKxf4Ph4v8jOj 2HjHKIF3azuV23NGrP/L0kmkIoLbU77FsGzLAIB4etR8CjLv/mm1W+Rm9wG7Wi20Qf 9bCfB5IoI0J0AUn4bKcg7P3o/CnocQo4hvP2QVxf1pC/4M65ApXfrRdTznGR7HL9EL UCDZyXx1Bbm4fIIthh7q4BpOhb2peNDAk4t3Me9zhw16A5tgAwshGbvt8aoBahblXj yINBs05SJGpZQ== From: Leon Romanovsky To: Marek Szyprowski Cc: Leon Romanovsky , Jason Gunthorpe , Abdiel Janulgue , Alexander Potapenko , Alex Gaynor , Andrew Morton , Christoph Hellwig , Danilo Krummrich , David Hildenbrand , 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 v5 12/16] mm/hmm: migrate to physical address-based DMA mapping API Date: Tue, 2 Sep 2025 17:48:49 +0300 Message-ID: <90d2f14352494d615d3a5d1251126c88f96a4171.1756822782.git.leon@kernel.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" 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 h= mm_dma_map *map, if (WARN_ON_ONCE(dma_need_unmap(dev) && !dma_addrs)) goto error; =20 - dma_addr =3D dma_map_page(dev, page, 0, map->dma_entry_size, - DMA_BIDIRECTIONAL); + dma_addr =3D dma_map_phys(dev, paddr, map->dma_entry_size, + DMA_BIDIRECTIONAL, 0); if (dma_mapping_error(dev, dma_addr)) goto error; =20 @@ -819,8 +819,8 @@ bool hmm_dma_unmap_pfn(struct device *dev, struct hmm_d= ma_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); =20 pfns[idx] &=3D ~(HMM_PFN_DMA_MAPPED | HMM_PFN_P2PDMA | HMM_PFN_P2PDMA_BUS); --=20 2.50.1