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umad_register2(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | REGISTRATION ATTRIBUTE STRUCTURE | RETURN VALUE | SEE ALSO | AUTHOR | COLOPHON 

UMAD_REGISTER2(3)       OpenIB Programmer's Manual      UMAD_REGISTER2(3)

NAME         top

       umad_register2 - register the specified management class and
       version for port

SYNOPSIS         top

       #include <infiniband/umad.h>

       int umad_register2(int port_fd, struct umad_reg_attr *attr, uint32_t *agent_id);

DESCRIPTION         top

       umad_register2() registers for a MAD agent using the provided
       registration attributes

       port_fd the port on which to register the agent

       attr The registration attributes as defined by the structure
       passed.  See below for details of this structure.

       agent_id returned on success.  agent_id identifies the kernel MAD
       agent a MAD is received by or to be sent by.  agent_id is returned
       in the umad header "struct ib_user_mad" on recv and specified in
       umad_send when sending.

REGISTRATION ATTRIBUTE STRUCTURE         top

       struct umad_reg_attr {
               uint8_t    mgmt_class;
               uint8_t    mgmt_class_version;
               uint32_t   flags;
               uint64_t   method_mask[2];
               uint32_t   oui;
               uint8_t    rmpp_version;
       };

       mgmt_class
       Management class to register for.

       mgmt_class_version
       Management class version to register for.

       flags
       Registration flags.  If a flag specified is not supported by the kernel,
       an error is returned, and the supported flags are returned in this field.

       Current flags are:
               UMAD_USER_RMPP -- flag to indicate the kernel should not process
               RMPP packets.  All RMPP packets will be treated like individual
               MADs.  The user is responsible for implementing the RMPP
               protocol.

       method_mask
       A bit mask which indicates which unsolicited methods this agent should
       receive.  Setting this array to 0 will result in the agent only
       receiving response MADs for which a request was sent.

       oui
       The oui (in host order) to use for vendor classes 0x30 - 0x4f.
       Otherwise ignored.

       rmpp_version
       If the class supports RMPP and kernel RMPP is enabled (the default)
       indicate which rmpp_version to use.

RETURN VALUE         top

       umad_register2() returns 0 on success and +ERRNO on failure.

SEE ALSO         top

       umad_unregister(3)

AUTHOR         top

       Ira Weiny <ira.weiny@intel.com>

COLOPHON         top

       This page is part of the rdma-core (RDMA Core Userspace Libraries
       and Daemons) project.  Information about the project can be found
       at ⟨https://github.com/linux-rdma/rdma-core⟩.  If you have a bug
       report for this manual page, send it to
       linux-rdma@vger.kernel.org.  This page was obtained from the
       project's upstream Git repository
       ⟨https://github.com/linux-rdma/rdma-core.git⟩ on 2025-08-11.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2025-08-04.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there is
       a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

OpenIB                        March 25, 2014            UMAD_REGISTER2(3)

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