linux.git/include/rdma, branch master

RDMA/core: Check id_priv->restricted_node_type in cma_listen_on_dev()

2026-02-25T12:50:10+00:00

When listening on wildcard addresses we have a global list for the application
layer rdma_cm_id and for any existing device or any device added in future we
try to listen on any wildcard listener.

When the listener has a restricted_node_type we should prevent listening on
devices with a different node type.

While there fix the documentation comment of rdma_restrict_node_type()
to include rdma_resolve_addr() instead of having rdma_bind_addr() twice.

Fixes: a760e80e90f5 ("RDMA/core: introduce rdma_restrict_node_type()")
Cc: Jason Gunthorpe 
Cc: Leon Romanovsky 
Cc: Steve French 
Cc: Namjae Jeon 
Cc: Tom Talpey 
Cc: Long Li 
Cc: linux-rdma@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Signed-off-by: Stefan Metzmacher 
Link: https://patch.msgid.link/20260224165951.3582093-2-metze@samba.org
Signed-off-by: Leon Romanovsky

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

2026-02-13T01:05:20+00:00

Pull rdma updates from Jason Gunthorpe:
 "Usual smallish cycle. The NFS biovec work to push it down into RDMA
  instead of indirecting through a scatterlist is pretty nice to see,
  been talked about for a long time now.

   - Various code improvements in irdma, rtrs, qedr, ocrdma, irdma, rxe

   - Small driver improvements and minor bug fixes to hns, mlx5, rxe,
     mana, mlx5, irdma

   - Robusness improvements in completion processing for EFA

   - New query_port_speed() verb to move past limited IBA defined speed
     steps

   - Support for SG_GAPS in rts and many other small improvements

   - Rare list corruption fix in iwcm

   - Better support different page sizes in rxe

   - Device memory support for mana

   - Direct bio vec to kernel MR for use by NFS-RDMA

   - QP rate limiting for bnxt_re

   - Remote triggerable NULL pointer crash in siw

   - DMA-buf exporter support for RDMA mmaps like doorbells"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (66 commits)
  RDMA/mlx5: Implement DMABUF export ops
  RDMA/uverbs: Add DMABUF object type and operations
  RDMA/uverbs: Support external FD uobjects
  RDMA/siw: Fix potential NULL pointer dereference in header processing
  RDMA/umad: Reject negative data_len in ib_umad_write
  IB/core: Extend rate limit support for RC QPs
  RDMA/mlx5: Support rate limit only for Raw Packet QP
  RDMA/bnxt_re: Report QP rate limit in debugfs
  RDMA/bnxt_re: Report packet pacing capabilities when querying device
  RDMA/bnxt_re: Add support for QP rate limiting
  MAINTAINERS: Drop RDMA files from Hyper-V section
  RDMA/uverbs: Add __GFP_NOWARN to ib_uverbs_unmarshall_recv() kmalloc
  svcrdma: use bvec-based RDMA read/write API
  RDMA/core: add rdma_rw_max_sge() helper for SQ sizing
  RDMA/core: add MR support for bvec-based RDMA operations
  RDMA/core: use IOVA-based DMA mapping for bvec RDMA operations
  RDMA/core: add bio_vec based RDMA read/write API
  RDMA/irdma: Use kvzalloc for paged memory DMA address array
  RDMA/rxe: Fix race condition in QP timer handlers
  RDMA/mana_ib: Add device‑memory support
  ...

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: introduce rdma_restrict_node_type()

2026-02-08T23:12:58+00:00

For smbdirect it required to use different ports depending
on the RDMA protocol. E.g. for iWarp 5445 is needed
(as tcp port 445 already used by the raw tcp transport for SMB),
while InfiniBand, RoCEv1 and RoCEv2 use port 445, as they
use an independent port range (even for RoCEv2, which uses udp
port 4791 itself).

Currently ksmbd is not able to function correctly at
all if the system has iWarp (RDMA_NODE_RNIC) interface(s)
and any InfiniBand, RoCEv1 and/or RoCEv2 interface(s)
at the same time.

And cifs.ko uses 5445 with a fallback to 445, which
means depending on the available interfaces, it tries
5445 in the RoCE range or may tries iWarp with 445
as a fallback. This leads to strange error messages
and strange network captures.

To avoid these problems they will be able to
use rdma_restrict_node_type(RDMA_NODE_RNIC) before
trying port 5445 and rdma_restrict_node_type(RDMA_NODE_IB_CA)
before trying port 445. It means we'll get early
-ENODEV early from rdma_resolve_addr() without any
network traffic and timeouts.

This is designed to be called before calling any
of rdma_bind_addr(), rdma_resolve_addr() or rdma_listen().

Cc: Jason Gunthorpe 
Cc: Steve French 
Cc: Tom Talpey 
Cc: Long Li 
Cc: linux-rdma@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Acked-by: Leon Romanovsky 
Acked-by: Namjae Jeon 
Signed-off-by: Stefan Metzmacher 
Signed-off-by: Steve French

RDMA/core: add rdma_rw_max_sge() helper for SQ sizing

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

svc_rdma_accept() computes sc_sq_depth as the sum of rq_depth and the
number of rdma_rw contexts (ctxts). This value is used to allocate the
Send CQ and to initialize the sc_sq_avail credit pool.

However, when the device uses memory registration for RDMA operations,
rdma_rw_init_qp() inflates the QP's max_send_wr by a factor of three
per context to account for REG and INV work requests. The Send CQ and
credit pool remain sized for only one work request per context,
causing Send Queue exhaustion under heavy NFS WRITE workloads.

Introduce rdma_rw_max_sge() to compute the actual number of Send Queue
entries required for a given number of rdma_rw contexts. Upper layer
protocols call this helper before creating a Queue Pair so that their
Send CQs and credit accounting match the QP's true capacity.

Update svc_rdma_accept() to use rdma_rw_max_sge() when computing
sc_sq_depth, ensuring the credit pool reflects the work requests
that rdma_rw_init_qp() will reserve.

Reviewed-by: Christoph Hellwig 
Fixes: 00bd1439f464 ("RDMA/rw: Support threshold for registration vs scattering to local pages")
Signed-off-by: Chuck Lever 
Link: https://patch.msgid.link/20260128005400.25147-5-cel@kernel.org
Signed-off-by: Leon Romanovsky

RDMA/core: add MR support for bvec-based RDMA operations

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

The bvec-based RDMA API currently returns -EOPNOTSUPP when Memory
Region registration is required. This prevents iWARP devices from
using the bvec path, since iWARP requires MR registration for RDMA
READ operations. The force_mr debug parameter is also unusable with
bvec input.

Add rdma_rw_init_mr_wrs_bvec() to handle MR registration for bvec
arrays. The approach creates a synthetic scatterlist populated with
DMA addresses from the bvecs, then reuses the existing ib_map_mr_sg()
infrastructure. This avoids driver changes while keeping the
implementation small.

The synthetic scatterlist is stored in the rdma_rw_ctx for cleanup.
On destroy, the MRs are returned to the pool and the bvec DMA
mappings are released using the stored addresses.

Signed-off-by: Chuck Lever 
Link: https://patch.msgid.link/20260128005400.25147-4-cel@kernel.org
Reviewed-by: Christoph Hellwig 
Signed-off-by: Leon Romanovsky

RDMA/core: use IOVA-based DMA mapping for bvec RDMA operations

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

The bvec RDMA API maps each bvec individually via dma_map_phys(),
requiring an IOTLB sync for each mapping. For large I/O operations
with many bvecs, this overhead becomes significant.

The two-step IOVA API (dma_iova_try_alloc / dma_iova_link /
dma_iova_sync) allocates a contiguous IOVA range upfront, links
all physical pages without IOTLB syncs, then performs a single
sync at the end. This reduces IOTLB flushes from O(n) to O(1).

It also requires only a single output dma_addr_t compared to extra
per-input element storage in struct scatterlist.

Reviewed-by: Christoph Hellwig 
Signed-off-by: Chuck Lever 
Link: https://patch.msgid.link/20260128005400.25147-3-cel@kernel.org
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