{"id":2225264,"url":"http://patchwork.ozlabs.org/api/covers/2225264/?format=json","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/projects/28/?format=json","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/people/92088/?format=json","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/series/500663/?format=json","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 ","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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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(-)"}