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{ "id": 2225264, "url": "http://patchwork.ozlabs.org/api/1.2/covers/2225264/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pci/cover/20260420183920.3626389-1-zhipingz@meta.com/", "project": { "id": 28, "url": "http://patchwork.ozlabs.org/api/1.2/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": "<20260420183920.3626389-1-zhipingz@meta.com>", "list_archive_url": null, "date": "2026-04-20T18:39:14", "name": "[v1,0/2] Retrieve TPH from dma-buf for PCIe P2P memory access", "submitter": { "id": 92088, "url": "http://patchwork.ozlabs.org/api/1.2/people/92088/?format=api", "name": "Zhiping Zhang", "email": "zhipingz@meta.com" }, "mbox": "http://patchwork.ozlabs.org/project/linux-pci/cover/20260420183920.3626389-1-zhipingz@meta.com/mbox/", "series": [ { "id": 500663, "url": "http://patchwork.ozlabs.org/api/1.2/series/500663/?format=api", "web_url": "http://patchwork.ozlabs.org/project/linux-pci/list/?series=500663", "date": "2026-04-20T18:39:14", "name": "Retrieve TPH from dma-buf for PCIe P2P memory access", "version": 1, "mbox": "http://patchwork.ozlabs.org/series/500663/mbox/" } ], "comments": "http://patchwork.ozlabs.org/api/covers/2225264/comments/", "headers": { "Return-Path": "\n <linux-pci+bounces-52794-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=lmTLwZTJ;\n\tdkim-atps=neutral", "legolas.ozlabs.org;\n spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org\n (client-ip=172.105.105.114; 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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=v1B/weXcqQ1lWLTVVV\n\t0vhTvXO65+/046zoF1VJqryV4=; b=lmTLwZTJjAs6lgOoHWNSrsl3aPUh3AG54U\n\tdTO4XGquprYR6q/ph4MhY0BSFDVGQkVWURiqlnvll08oow6VhceG+As1lhSU+j3D\n\t04nQCEfN2Nd+5ZnNAs//DCJFMIomdywVDMzZXujLuNBlYZM5uOMlWNUXrobAz4H5\n\tImqMUODQ8YCv7+toj7lYSfAkqLdwgwbD50VP/SZEGkhOImzlaApHtJ7/TUaHSW2J\n\tRKZ22WLJniIdHy1TFWxJvzWcEMltloQqiGQB3AGpaigUKdQsxWE61Gt2uX+b6h5i\n\t95+fUbdAIH+J+wpTcNY4hr52T10FTqvgaZJLe7c/unPp5d7+3WNQ==", "From": "Zhiping Zhang <zhipingz@meta.com>", "To": "Stanislav Fomichev <sdf@meta.com>, Keith Busch <kbusch@kernel.org>", "CC": "Jason Gunthorpe <jgg@ziepe.ca>, Leon Romanovsky <leon@kernel.org>,\n Bjorn\n 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>, Yochai Cohen <yochai@nvidia.com>,\n Yishai\n Hadas <yishaih@nvidia.com>, Zhiping Zhang <zhipingz@meta.com>", "Subject": "[PATCH v1 0/2] Retrieve TPH from dma-buf for PCIe P2P memory access", "Date": "Mon, 20 Apr 2026 11:39:14 -0700", "Message-ID": "<20260420183920.3626389-1-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-Transfer-Encoding": "quoted-printable", "X-FB-Internal": "Safe", "Content-Type": "text/plain", "X-Authority-Analysis": "v=2.4 cv=AvHeGu9P c=1 sm=1 tr=0 ts=69e67418 cx=c_pps\n a=CB4LiSf2rd0gKozIdrpkBw==:117 a=CB4LiSf2rd0gKozIdrpkBw==:17\n a=A5OVakUREuEA:10 a=VkNPw1HP01LnGYTKEx00:22 a=7x6HtfJdh03M6CCDgxCd:22\n a=8elwO82fXORLTBIkMd32:22 a=VwQbUJbxAAAA:8 a=VabnemYjAAAA:8\n a=XtSdSgJ7MZthVsN6br0A:9 a=gKebqoRLp9LExxC7YDUY:22", "X-Proofpoint-GUID": "QdfBhvHh-YXuNzUokTTnjy7SCYVCLKiy", "X-Proofpoint-Spam-Details-Enc": "AW1haW4tMjYwNDIwMDE4MiBTYWx0ZWRfX/YC3Z/aeYnic\n c1GOp8rl3b1F5ljT+YFhmGni53Qe3/GZXtrVOEqrNWIXVWM+T9PayfLTRZN2GSs/2z1Tyj6aRl8\n 57g7QgmgHQqeJDxBazDQFmMBd1UDEL7l4knSeyC1+bqZFQ/wC1dN3My0K6w38W+SIlo8ncRpWBG\n Z1KM8JqzDz4b1jznPXdr+Udzir5dN+lvcvdpUwTaDJQ7HtzolXMLeKnjweltDg2YCfToyDKnmrr\n SOpOzb7uIGc/8QQaEZB+Jr0IsFJAhDTXgWJwfC0jlznyGYwxja9SgekZhdQqE6pOcgdauLOMTi2\n hjlgrlIrQV5aMFM5QcdoYn3WC2BgFOzsQ7QPHrCVzQnJzaf/2EPm5owSptTQwYWonhrEXY2w6Vo\n zo47NFSvSk4iq2rR9UzadCNwCbmFFHJLOnybt0Omof/1il36OGzQ/+RX+OWRxns8SCTDitn4WTV\n S4pka8CRMR1DCAYJjaw==", "X-Proofpoint-ORIG-GUID": "QdfBhvHh-YXuNzUokTTnjy7SCYVCLKiy", "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=2026-04-20_03,2026-04-20_02,2025-10-01_01" }, "content": "Currently, TPH steering tags are derived for CPUs via ACPI. This series\nextends the VFIO dma-buf path so a vfio-based accelerator can attach TPH\nmetadata to an exported dma-buf, and lets mlx5 consume that metadata\nwhen registering a dma-buf MR for PCIe peer-to-peer access.\n\nPatch 1 adds a dma-buf callback to retrieve raw TPH metadata and updates\nVFIO_DEVICE_FEATURE_DMA_BUF to carry the optional steering tag and\nprocessing hint in one extra trailing entries[] object without changing\nthe base uAPI layout. Patch 2 consumes the exported TPH metadata in mlx5\nand converts the raw steering tag into an mlx5 steering-tag index.\n\nPrevious RFC link:\nhttps://lore.kernel.org/linux-pci/20260324234615.3731237-1-zhipingz@meta.com/T/#u\n\nZhiping Zhang (2):\n vfio: add callback to get tph info for dma-buf\n RDMA/mlx5: get tph for p2p access when registering dma-buf mr\n\n drivers/infiniband/hw/mlx5/mr.c | 38 ++++++++++++\n .../net/ethernet/mellanox/mlx5/core/lib/st.c | 25 +++++---\n drivers/vfio/pci/vfio_pci_dmabuf.c | 62 ++++++++++++++-----\n include/linux/dma-buf.h | 17 +++++\n include/linux/mlx5/driver.h | 7 +++\n include/uapi/linux/vfio.h | 28 +++++++--\n 6 files changed, 151 insertions(+), 26 deletions(-)" }