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{ "id": 2231544, "url": "http://patchwork.ozlabs.org/api/covers/2231544/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pci/cover/20260430200704.352228-1-zhipingz@meta.com/", "project": { "id": 28, "url": "http://patchwork.ozlabs.org/api/projects/28/?format=api", "name": "Linux PCI development", "link_name": "linux-pci", "list_id": "linux-pci.vger.kernel.org", "list_email": "linux-pci@vger.kernel.org", "web_url": null, "scm_url": null, "webscm_url": null, "list_archive_url": "", "list_archive_url_format": "", "commit_url_format": "" }, "msgid": "<20260430200704.352228-1-zhipingz@meta.com>", "list_archive_url": null, "date": "2026-04-30T20:06:55", "name": "[v2,0/2] vfio/dma-buf: add TPH support for peer-to-peer access", "submitter": { "id": 92088, "url": "http://patchwork.ozlabs.org/api/people/92088/?format=api", "name": "Zhiping Zhang", "email": "zhipingz@meta.com" }, "mbox": "http://patchwork.ozlabs.org/project/linux-pci/cover/20260430200704.352228-1-zhipingz@meta.com/mbox/", "series": [ { "id": 502373, "url": "http://patchwork.ozlabs.org/api/series/502373/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pci/list/?series=502373", "date": "2026-04-30T20:06:56", "name": "vfio/dma-buf: add TPH support for peer-to-peer access", "version": 2, "mbox": "http://patchwork.ozlabs.org/series/502373/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/covers/2231544/comments/", "headers": { "Return-Path": "\n <linux-pci+bounces-53539-incoming=patchwork.ozlabs.org@vger.kernel.org>", "X-Original-To": [ "incoming@patchwork.ozlabs.org", "linux-pci@vger.kernel.org" ], "Delivered-To": "patchwork-incoming@legolas.ozlabs.org", "Authentication-Results": [ "legolas.ozlabs.org;\n\tdkim=pass (2048-bit key;\n unprotected) header.d=meta.com header.i=@meta.com header.a=rsa-sha256\n header.s=s2048-2025-q2 header.b=HQo+XzrX;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=2600:3c15:e001:75::12fc:5321; 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arc=none smtp.client-ip=67.231.145.42", "DKIM-Signature": "v=1; a=rsa-sha256; c=relaxed/relaxed; d=meta.com; h=cc\n\t:content-transfer-encoding:content-type:date:from:message-id\n\t:mime-version:subject:to; s=s2048-2025-q2; bh=sInQ2EyrWhVx820/ik\n\tKwwXHwtxBsZT0OSVOIPwT0byA=; b=HQo+XzrXlbX8/6iOvE/YN8Zko6ss3hysN6\n\tY/mWtEnP3GhvwA1IdF9zC5EjvLkwn6Qq/X1nZrrguds2GE/W7pFtwQCZsUdQyp3o\n\txTa25oHLS8pkDwIwDGAh0bTTzSshMz1oBJ3ga44sHPx9fvYpX8feEZBwYXQmZqm8\n\tmpZU3RLcFlnIFbHloCMyIcTIXhFn2siUBzsLxBAjdp5erWA3iDBDhUmyG6X5oJfa\n\t08UYYL2b+JGwMccKN1QFNK6OMFYHdQfmhLiQelwMK0RjWNEs7hehhVBA3KArfAk/\n\t3luUPzgI4WqaG3tOKXO1yBMTAYuEmBnaRTfcCP4jXXYOC7yVqViQ==", "From": "Zhiping Zhang <zhipingz@meta.com>", "To": "Alex Williamson <alex@shazbot.org>, Jason Gunthorpe <jgg@ziepe.ca>,\n Leon\n Romanovsky <leon@kernel.org>", "CC": "Bjorn Helgaas <helgaas@kernel.org>, <linux-rdma@vger.kernel.org>,\n <linux-pci@vger.kernel.org>, <netdev@vger.kernel.org>,\n <dri-devel@lists.freedesktop.org>, Keith Busch <kbusch@kernel.org>,\n Yochai\n Cohen <yochai@nvidia.com>, Yishai Hadas <yishaih@nvidia.com>,\n Zhiping Zhang\n\t<zhipingz@meta.com>", "Subject": "[PATCH v2 0/2] vfio/dma-buf: add TPH support for peer-to-peer access", "Date": "Thu, 30 Apr 2026 13:06:55 -0700", "Message-ID": "<20260430200704.352228-1-zhipingz@meta.com>", "X-Mailer": "git-send-email 2.52.0", "Precedence": "bulk", "X-Mailing-List": "linux-pci@vger.kernel.org", "List-Id": "<linux-pci.vger.kernel.org>", "List-Subscribe": "<mailto:linux-pci+subscribe@vger.kernel.org>", "List-Unsubscribe": "<mailto:linux-pci+unsubscribe@vger.kernel.org>", "MIME-Version": "1.0", "Content-Type": "text/plain; charset=\"UTF-8\"", "Content-Transfer-Encoding": "quoted-printable", "X-FB-Internal": "Safe", "X-Proofpoint-Spam-Details-Enc": "AW1haW4tMjYwNDMwMDIwOCBTYWx0ZWRfX64gPoCTIYNtE\n UpgNAxIADXLKxdTFdRoVbeFiw1mrxdyOyzU557bw1CQGiNwjj7Eavy/HKRLXCtVmnFvRLE0w4SW\n SLZ1wtopENn1EaB6b2gcKZMAaNvjs/gODvm0C9NgBrLMLHoVfD1XJOs27jZnhE0uCarfRzOoy8g\n 8xSHB1H++bzXahUcbpWPa/TyMeS38Zz2zkezAh0t9QC/gQU5tregWyMq/JStm+t+Lx7ZV6gI8tt\n svi9Nan4FDy2f8L4h0jqxT0h5VDyReG5ba6XUOhrr5sPYObC34JATcww53tjbB0/o/Ko72ghIdW\n 8Lbja32o6SikRmGQuDmXILuoyntMLfuC4aHChtV6xfTHzk+4sVpaQhwDp6Y0JQzRWm9r5efCx3t\n MkQtpLRXNJ7PZjHpGzU/QozykKFx3jsU0AOWL8b98r/+b/jUXj9GQO0Yfu0AmHNMMc/ywoTKNfB\n uQcWRnthAVq0th9JU5A==", "X-Authority-Analysis": "v=2.4 cv=NoDhtcdJ c=1 sm=1 tr=0 ts=69f3b7a2 cx=c_pps\n a=MfjaFnPeirRr97d5FC5oHw==:117 a=MfjaFnPeirRr97d5FC5oHw==:17\n a=IkcTkHD0fZMA:10 a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22\n a=7x6HtfJdh03M6CCDgxCd:22 a=tpM8CJlwf7uhpglF1g9U:22 a=VwQbUJbxAAAA:8\n a=VabnemYjAAAA:8 a=NbcebPYJtCDKC3IOK8sA:9 a=QEXdDO2ut3YA:10\n a=gKebqoRLp9LExxC7YDUY:22", "X-Proofpoint-GUID": "uQNYinGjMTMSWjqixtsM7rQOoETtHfGL", "X-Proofpoint-ORIG-GUID": "uQNYinGjMTMSWjqixtsM7rQOoETtHfGL", "X-Proofpoint-Virus-Version": "vendor=baseguard\n engine=ICAP:2.0.293,Aquarius:18.0.1143,Hydra:6.1.51,FMLib:17.12.100.49\n definitions=2026-04-30_05,2026-04-30_02,2025-10-01_01" }, "content": "This series adds TLP Processing Hints (TPH) support to the VFIO dma-buf\nexport path, allowing importing drivers (e.g. mlx5) to use the exporter's\nsteering tag when performing peer-to-peer DMA into a VFIO-owned device.\n\nChanges since v1:\n - VFIO_DEVICE_FEATURE_DMA_BUF is now unchanged — dma_ranges[],\n __counted_by(nr_ranges), and flags==0 are all preserved\n - Added a new VFIO_DEVICE_FEATURE_DMA_BUF_TPH (feature 13) as a separate\n SET ioctl that takes a dmabuf fd, validates it belongs to this vfio\n device, and stores the steering tag + processing hint under memory_lock\n - Kept the dma_buf_ops.get_tph callback as the general exporter-side\n interface for importing drivers\n\nPatch 1 adds the dma-buf get_tph callback and the new vfio uAPI.\nPatch 2 wires up the mlx5 RDMA driver as a consumer.\n\nPrevious links:\nhttps://lore.kernel.org/linux-pci/20260324234615.3731237-1-zhipingz@meta.com/\nhttps://lore.kernel.org/dri-devel/20260420183920.3626389-1-zhipingz@meta.com/\n\nZhiping Zhang (2):\n vfio: add dma-buf get_tph callback and DMA_BUF_TPH feature\n RDMA/mlx5: get tph for p2p access when registering dma-buf mr\n\n drivers/infiniband/hw/mlx5/mr.c | 38 +++++++\n drivers/net/ethernet/mellanox/mlx5/core/lib/st.c | 25 +++--\n drivers/vfio/pci/vfio_pci_core.c | 3 +\n drivers/vfio/pci/vfio_pci_dmabuf.c | 65 ++++++++++++\n drivers/vfio/pci/vfio_pci_priv.h | 11 ++\n include/linux/dma-buf.h | 17 +++\n include/linux/mlx5/driver.h | 7 ++\n include/uapi/linux/vfio.h | 22 ++++\n 8 files changed, 180 insertions(+), 8 deletions(-)\n\n--\n2.47.1" }