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 04377CA1013 for ; Thu, 4 Sep 2025 18:31:46 +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=D4SM6zHJ9Q6ObBfi9kz8op3wvjKvHEZA6J8C6N7vBkM=; b=x5amDFLUPUcW+hsw6xOPYrgyHm lgvgSbvOWPsSpoPMotIUZ0+eFKnISWrVWPevCEbbkUcqO0LBdaj+CgwZ6mUVUZe7VGNGf6UI1ET9r VR3zp1U4cDyaHYNpJRWlJ/982ZLMICUuOmEKWS03MEXE4R2h4jLIIzaEH72Q2yUPJ7lKsTVP0FFDr GYWmAvLR81zP1w8ub5iiooYlEnmaFUUCTXsjHGruOG8xGfa4gqxX8VdyopuTSDT+EA8IdIchpCZX2 io9z8vRfH9tkQfawcMfG5eWEVt3L3nahD99s1DfC26XOoZNwjhri1lc3VAGFusid7j5bTWkfZoZUB ErsQEChA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uuEkH-0000000DaGh-1KIt; Thu, 04 Sep 2025 18:31:41 +0000 Received: from sea.source.kernel.org ([172.234.252.31]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1utSKs-00000000Tpv-3yYw for linux-nvme@lists.infradead.org; Tue, 02 Sep 2025 14:50:16 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id A15CE43588; Tue, 2 Sep 2025 14:50:14 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D3108C4CEED; Tue, 2 Sep 2025 14:50:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1756824614; bh=5GnXky7X8jRP4E4M761xyU7kxSqR5w3y9HvcAnisW/0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rJeu6B43+1PA3hIr12hg0lnVgq8hEaO1Lw0dSu66C4Hxh6OtUnH4qrmq2UzSSZ1N4 l2ZMHW11no8o4RgcofoNHTdHE1yoSWlx22rWWSHOD8+Ogvu4ojzleuOhx12qfasdh8 1xBycpNin9JG/1JisPEuSXMSjGw3Xeby21NvKY8cKczB0oynk2yRys0EmsHljVnB3u KBLTyBq9WFsVfFALrQa4WJtvJqzt56sC8sAjNNKhzQLMvhf/aVz1+461ufH6pc4SF9 +Mv7reAnOosbLyMyMqxFSSvL8KoRwphakYFROv2rFhXteTJEarDn/NkqrxQfsDao9k qBoW5Cs7du2bQ== 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 13/16] mm/hmm: properly take MMIO path Date: Tue, 2 Sep 2025 17:48:50 +0300 Message-ID: <4aac9ae9c0fe39a2e47139fae6d602f71d90bd09.1756822782.git.leon@kernel.org> 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-20250902_075015_030011_A3BAB8E1 X-CRM114-Status: GOOD ( 12.15 ) X-Mailman-Approved-At: Thu, 04 Sep 2025 09:33:16 -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 In case peer-to-peer transaction traverses through host bridge, the IOMMU needs to have IOMMU_MMIO flag, together with skip of CPU sync. The latter was handled by provided DMA_ATTR_SKIP_CPU_SYNC flag, but IOMMU flag was missed, due to assumption that such memory can be treated as regular one. Reuse newly introduced DMA attribute to properly take MMIO path. Reviewed-by: Jason Gunthorpe Signed-off-by: Leon Romanovsky --- mm/hmm.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/mm/hmm.c b/mm/hmm.c index 015ab243f081..6556c0e074ba 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -746,7 +746,7 @@ dma_addr_t hmm_dma_map_pfn(struct device *dev, struct hmm_dma_map *map, case PCI_P2PDMA_MAP_NONE: break; case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE: - attrs |= DMA_ATTR_SKIP_CPU_SYNC; + attrs |= DMA_ATTR_MMIO; pfns[idx] |= HMM_PFN_P2PDMA; break; case PCI_P2PDMA_MAP_BUS_ADDR: @@ -776,7 +776,7 @@ dma_addr_t hmm_dma_map_pfn(struct device *dev, struct hmm_dma_map *map, goto error; dma_addr = dma_map_phys(dev, paddr, map->dma_entry_size, - DMA_BIDIRECTIONAL, 0); + DMA_BIDIRECTIONAL, attrs); if (dma_mapping_error(dev, dma_addr)) goto error; @@ -811,16 +811,17 @@ bool hmm_dma_unmap_pfn(struct device *dev, struct hmm_dma_map *map, size_t idx) if ((pfns[idx] & valid_dma) != valid_dma) return false; + if (pfns[idx] & HMM_PFN_P2PDMA) + attrs |= DMA_ATTR_MMIO; + if (pfns[idx] & HMM_PFN_P2PDMA_BUS) ; /* no need to unmap bus address P2P mappings */ - else if (dma_use_iova(state)) { - if (pfns[idx] & HMM_PFN_P2PDMA) - attrs |= DMA_ATTR_SKIP_CPU_SYNC; + else if (dma_use_iova(state)) dma_iova_unlink(dev, state, idx * map->dma_entry_size, map->dma_entry_size, DMA_BIDIRECTIONAL, attrs); - } else if (dma_need_unmap(dev)) + else if (dma_need_unmap(dev)) dma_unmap_phys(dev, dma_addrs[idx], map->dma_entry_size, - DMA_BIDIRECTIONAL, 0); + DMA_BIDIRECTIONAL, attrs); pfns[idx] &= ~(HMM_PFN_DMA_MAPPED | HMM_PFN_P2PDMA | HMM_PFN_P2PDMA_BUS); -- 2.50.1