rdma_set_option(3) — Linux manual page

RDMA_SET_OPTION(3)    Librdmacm Programmer's Manual    RDMA_SET_OPTION(3)

NAME         top

       rdma_set_option - Set communication options for an rdma_cm_id.

SYNOPSIS         top

       #include <rdma/rdma_cma.h>

       int rdma_set_option (struct rdma_cm_id *id, int level, int
       optname, void *optval, size_t optlen);

ARGUMENTS         top

       id          RDMA identifier.

       level       Protocol level of the option to set.

       optname     Name of the option, relative to the level, to set.

       optval      Reference to the option data.  The data is dependent
                   on the level and optname.

       optlen      The size of the %optval buffer.

DESCRIPTION         top

       Sets communication options for an rdma_cm_id.  This call is used
       to override the default system settings.

       optname can be one of

       RDMA_OPTION_ID_TOS
                   Specify the quality of service provided by a
                   connection.  The expected optlen is size of uint8_t.

       RDMA_OPTION_ID_REUSEADDR
                   Bound the rdma_cm_id to a reuseable address. This will
                   allow other users to bind to that same address.  The
                   expected optlen is size of int.

       RDMA_OPTION_ID_AFONLY
                   Set IPV6_V6ONLY socket.  The expected optlen is size
                   of int.

       RDMA_OPTION_IB_PATH
                   Set IB path record data.  The expected optlen is size
                   of struct ibv_path_data[].

       RDMA_OPTION_ID_ACK_TIMEOUT
                   Set QP ACK timeout.  The value calculated according to
                   the formula 4.096 * 2^(ack_timeout) usec.

RETURN VALUE         top

       Returns 0 on success, or -1 on error.  If an error occurs, errno
       will be set to indicate the failure reason.

NOTES         top

       Option details may be found in the relevant header files.

SEE ALSO         top

       rdma_create_id(3)

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
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librdmacm                       2007-08-06             RDMA_SET_OPTION(3)

Pages that refer to this page: rdma_create_id(3),  rdma_cm(7)

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