From nobody Sun Oct 5 14:38:38 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass(p=quarantine dis=none) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; t=1754311921; cv=none; d=zohomail.com; s=zohoarc; b=OUon0D51XjmJJaLvcLIX9M8zxYNYBBCdyM3ty16808xcPsoMBiqqSV7xRc3ccy7AKwS78Ta7OyE/dSyNvNkGWtt9qLrO6EXpM+ALYlP+zI95HEgpARmzYdjdcQ52NAxaDbc0F4S/TnzX3ZWMF/mTtIK2MIa0n2xrC43geyxCv70= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1754311921; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:Subject:To:To:Message-Id:Reply-To; bh=+vAkscLUbC2ztTvQppga8PLzPNKX2Zo6YASdCGH79rc=; b=NDhujJvMD5siNSbPR8edXfTTRknxnyx+sxNfNs6LKuK3vvDLzh5tMEG1IN/RrJbvLr9z1jI9q1BaBuCkwxmIuKlv+Ok/lYc8UNjUz8j7OEoHSpySgtXn1JxyvofAAUfpBJIxHCTzre2lP+/yEa49XflPU7GSXCQi/TQxKHWGW0g= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of lists.xenproject.org designates 192.237.175.120 as permitted sender) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org; dmarc=pass header.from= (p=quarantine dis=none) Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1754311921484728.4697035000986; Mon, 4 Aug 2025 05:52:01 -0700 (PDT) Received: from list by lists.xenproject.org with outflank-mailman.1069246.1433126 (Exim 4.92) (envelope-from ) id 1uiufN-00069a-KQ; Mon, 04 Aug 2025 12:51:49 +0000 Received: by outflank-mailman (output) from mailman id 1069246.1433126; Mon, 04 Aug 2025 12:51:49 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1uiufN-00068j-Gl; Mon, 04 Aug 2025 12:51:49 +0000 Received: by outflank-mailman (input) for mailman id 1069246; Mon, 04 Aug 2025 12:51:48 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1uiuY9-0006VD-Og for xen-devel@lists.xenproject.org; Mon, 04 Aug 2025 12:44:21 +0000 Received: from dfw.source.kernel.org (dfw.source.kernel.org [2604:1380:4641:c500::1]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id bd6de160-7130-11f0-a321-13f23c93f187; Mon, 04 Aug 2025 14:44:20 +0200 (CEST) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 1404A5C5F2E; Mon, 4 Aug 2025 12:44:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D4569C4CEE7; Mon, 4 Aug 2025 12:44:17 +0000 (UTC) X-Outflank-Mailman: Message body and most headers restored to incoming version X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: bd6de160-7130-11f0-a321-13f23c93f187 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1754311458; bh=dqwhbGWVl/oipogVPAPlJyJScmypxjmriuJlNMDqMFM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=twziXknBPqQkaMb4B7FpNHJ9HEUx7/M836/B/HOkWAaI0xU18AOGgranE1UPO3Z2A qByqLoklhRYu6bnu+x5ETVJIc+P+0Ju1mUTlWesgsxm9Uw2nnAUHgWFFcvipLZWsPr /X/Xgc0MrjwXWJE2eE8R2nPmVwtK2NoWOETrJzuVA7cF2pqqQw7TPbh3FX3McEN3on SLv84u5z+pYu1j0JRSH5twhBbzvn9nXehFR206rnivCVd5lTNcN4IpS/pX3K4gEYJR R30yvtOo8vlSCBPCeQNV8Tbj18sYkV187LjgCJFMSIphAwqv5UYBAvrh/Sqr87dLeL XA2ufQWKM0AXg== 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 v1 13/16] mm/hmm: properly take MMIO path Date: Mon, 4 Aug 2025 15:42:47 +0300 Message-ID: <79cf36301cc05d6dd1c88e9c3812ac5c3f57e32b.1754292567.git.leon@kernel.org> X-Mailer: git-send-email 2.50.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMail-DKIM: pass (identity @kernel.org) X-ZM-MESSAGEID: 1754311923155116600 Content-Type: text/plain; charset="utf-8" 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. Signed-off-by: Leon Romanovsky Reviewed-by: Jason Gunthorpe --- mm/hmm.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/mm/hmm.c b/mm/hmm.c index 015ab243f0813..6556c0e074ba8 100644 --- a/mm/hmm.c +++ b/mm/hmm.c @@ -746,7 +746,7 @@ dma_addr_t hmm_dma_map_pfn(struct device *dev, struct h= mm_dma_map *map, case PCI_P2PDMA_MAP_NONE: break; case PCI_P2PDMA_MAP_THRU_HOST_BRIDGE: - attrs |=3D DMA_ATTR_SKIP_CPU_SYNC; + attrs |=3D DMA_ATTR_MMIO; pfns[idx] |=3D 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 h= mm_dma_map *map, goto error; =20 dma_addr =3D dma_map_phys(dev, paddr, map->dma_entry_size, - DMA_BIDIRECTIONAL, 0); + DMA_BIDIRECTIONAL, attrs); if (dma_mapping_error(dev, dma_addr)) goto error; =20 @@ -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) !=3D valid_dma) return false; =20 + if (pfns[idx] & HMM_PFN_P2PDMA) + attrs |=3D 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 |=3D 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); =20 pfns[idx] &=3D ~(HMM_PFN_DMA_MAPPED | HMM_PFN_P2PDMA | HMM_PFN_P2PDMA_BUS); --=20 2.50.1