kernel/linux.git/include/rdma/ib_verbs.h, branch linux-7.0.y

RDMA/uverbs: Add DMABUF object type and operations

2026-02-09T04:50:41+00:00

Expose DMABUF functionality to userspace through the uverbs interface, enabling InfiniBand/RDMA devices to export PCI based memory regions (e.g. device memory) as DMABUF file descriptors. This allows zero-copy sharing of RDMA memory with other subsystems that support the dma-buf framework. A new UVERBS_OBJECT_DMABUF object type and allocation method were introduced. During allocation, uverbs invokes the driver to supply the rdma_user_mmap_entry associated with the given page offset (pgoff). Based on the returned rdma_user_mmap_entry, uverbs requests the driver to provide the corresponding physical-memory details as well as the driver’s PCI provider information. Using this information, dma_buf_export() is called; if it succeeds, uobj->object is set to the underlying file pointer returned by the dma-buf framework. The file descriptor number follows the standard uverbs allocation flow, but the file pointer comes from the dma-buf subsystem, including its own fops and private data. When an mmap entry is removed, uverbs iterates over its associated DMABUFs, marks them as revoked, and calls dma_buf_move_notify() so that their importers are notified. The same procedure applies during the disassociate flow; final cleanup occurs when the application closes the file. Signed-off-by: Yishai Hadas Signed-off-by: Edward Srouji Link: https://patch.msgid.link/20260201-dmabuf-export-v3-2-da238b614fe3@nvidia.com Signed-off-by: Leon Romanovsky

RDMA/core: add bio_vec based RDMA read/write API

2026-01-28T10:54:53+00:00

The existing rdma_rw_ctx_init() API requires callers to construct a scatterlist, which is then DMA-mapped page by page. Callers that already have data in bio_vec form (such as the NVMe-oF target) must first convert to scatterlist, adding overhead and complexity. Introduce rdma_rw_ctx_init_bvec() and rdma_rw_ctx_destroy_bvec() to accept bio_vec arrays directly. The new helpers use dma_map_phys() for hardware RDMA devices and virtual addressing for software RDMA devices (rxe, siw), avoiding intermediate scatterlist construction. Memory registration (MR) path support is deferred to a follow-up series; callers requiring MR-based transfers (iWARP devices or force_mr=1) receive -EOPNOTSUPP and should use the scatterlist API. Reviewed-by: Christoph Hellwig Signed-off-by: Chuck Lever Link: https://patch.msgid.link/20260128005400.25147-2-cel@kernel.org Signed-off-by: Leon Romanovsky

RDMA/core: Avoid exporting module local functions and remove not-used ones

2026-01-05T09:02:29+00:00

Some of the functions are local to the module and some are not used starting from commit 36783dec8d79 ("RDMA/rxe: Delete deprecated module parameters interface"). Delete and avoid exporting them. Signed-off-by: Parav Pandit Link: https://patch.msgid.link/20260104-ib-core-misc-v1-2-00367f77f3a8@nvidia.com Reviewed-by: Zhu Yanjun Reviewed-by: Kalesh AP Signed-off-by: Leon Romanovsky

IB/core: Add query_port_speed verb

2026-01-05T07:43:05+00:00

Add new ibv_query_port_speed() verb to enable applications to query the effective bandwidth of a port. This verb is particularly useful when the speed is not a multiplication of IB speed and width where width is 2^n. Signed-off-by: Or Har-Toov Reviewed-by: Mark Bloch Signed-off-by: Edward Srouji Signed-off-by: Leon Romanovsky

IB/core: Add helper to convert port attributes to data rate

2026-01-05T07:42:53+00:00

Introduce ib_port_attr_to_rate() to compute the data rate in 100 Mbps units (deci-Gb/sec) from a port's active_speed and active_width attributes. This generic helper removes duplicated speed-to-rate calculations, which are used by sysfs and the upcoming new verb. Signed-off-by: Or Har-Toov Reviewed-by: Mark Bloch Signed-off-by: Edward Srouji Signed-off-by: Leon Romanovsky

IB/core: Add async event on device speed change

2026-01-05T07:42:43+00:00

Add IB_EVENT_DEVICE_SPEED_CHANGE for notifying user applications on device's ports speed changes. Signed-off-by: Or Har-Toov Reviewed-by: Mark Bloch Signed-off-by: Edward Srouji Signed-off-by: Leon Romanovsky

RDMA/core: Add new IB rate for XDR (8x) support

2025-11-24T07:58:30+00:00

Add the new rates as defined in the Infiniband spec for XDR and 8x link width support. Furthermore, modify the utility conversion methods accordingly. Reference: IB Spec Release 1.8 Reviewed-by: Michael Guralnik Signed-off-by: Maher Sanalla Link: https://patch.msgid.link/20251120-speed-8-v1-1-e6a7efef8cb8@nvidia.com Reviewed-by: Kalesh AP Signed-off-by: Leon Romanovsky

RDMA/uverbs: fix some kernel-doc warnings

2025-10-20T15:45:46+00:00

Fix 49 kernel-doc warnings in ib_verbs.h: - Add struct short description for rdma_stat_desc, rdma_hw_stats. - Fix kernel-doc format for struct members (use ':' instead of '-') for several structs. - Don't use "/**" kernel-doc notation for struct members in ib_device_ops (most members are not documented and most of the kernel-doc was not formatted correctly). - Spell function parameters correctly in ib_dma_map_sgtable_attrs(), ib_device_try_get(), rdma_roce_rescan_device(). - Add kernel-doc for the function parameter in rdma_flow_label_to_udp_sport(). Signed-off-by: Randy Dunlap Link: https://patch.msgid.link/20251020034320.3011094-1-rdunlap@infradead.org Signed-off-by: Leon Romanovsky

IB: Extend UVERBS_METHOD_REG_MR to get DMAH

2025-07-23T05:42:11+00:00

Extend UVERBS_METHOD_REG_MR to get DMAH and pass it to all drivers. It will be used in mlx5 driver as part of the next patch from the series. Signed-off-by: Yishai Hadas Reviewed-by: Edward Srouji Link: https://patch.msgid.link/2ae1e628c0675db81f092cc00d3ad6fbf6139405.1752752567.git.leon@kernel.org Signed-off-by: Leon Romanovsky

RDMA/core: Introduce a DMAH object and its alloc/free APIs

2025-07-23T05:42:10+00:00

Introduce a new DMA handle (DMAH) object along with its corresponding allocation and deallocation APIs. This DMAH object encapsulates attributes intended for use in DMA transactions. While its initial purpose is to support TPH functionality, it is designed to be extensible for future features such as DMA PCI multipath, PCI UIO configurations, PCI traffic class selection, and more. Further details: ---------------- We ensure that a caller requesting a DMA handle for a specific CPU ID is permitted to be scheduled on it. This prevent a potential security issue where a non privilege user may trigger DMA operations toward a CPU that it's not allowed to run on. We manage reference counting for the DMAH object and its consumers (e.g., memory regions) as will be detailed in subsequent patches in the series. Signed-off-by: Yishai Hadas Reviewed-by: Edward Srouji Link: https://patch.msgid.link/2cad097e849597e49d6b61e6865dba878257f371.1752752567.git.leon@kernel.org Signed-off-by: Leon Romanovsky