UMAD_SET_GRH(3)          OpenIB Programmer´s Manual          UMAD_SET_GRH(3)

NAME         top

       umad_set_grh - set GRH fields within umad buffer using host ordering

SYNOPSIS         top

       #include <infiniband/umad.h>

       int umad_set_grh(void *umad, void *mad_addr);

DESCRIPTION         top

       umad_set_grh() sets the GRH fields (grh_present, gid, hop_limit,
       traffic_class, flow_label) within the specified umad buffer based on
       the mad_addr supplied. The provided mad_addr fields are expected to
       be in host order.  If the mad_addr pointer supplied is NULL, no GRH
       is set.  The argument mad_addr is a pointer to an ib_mad_addr_t
       struct, as specified in <infiniband/umad.h>.  The argument umad is a
       pointer to an ib_user_mad_t struct, as specified in

       typedef struct ib_mad_addr {
               uint32_t qpn;
               uint32_t qkey;
               uint16_t lid;
               uint8_t  sl;
               uint8_t  path_bits;
               uint8_t  grh_present;
               uint8_t  gid_index;
               uint8_t  hop_limit;
               uint8_t  traffic_class;
               uint8_t  gid[16];
               uint32_t flow_label;
       } ib_mad_addr_t;

       typedef struct ib_user_mad {
               uint32_t agent_id;
               uint32_t status;
               uint32_t timeout_ms;
               uint32_t retries;
               uint32_t length;
               ib_mad_addr_t addr;
               uint8_t  data[0];
       } ib_user_mad_t;

RETURN VALUE         top

       umad_set_grh() returns 0 on success, and a negative value on errors.
       Currently, there are no errors indicated.

SEE ALSO         top


AUTHOR         top

       Hal Rosenstock <>

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 
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OpenIB                          May 24, 2007                 UMAD_SET_GRH(3)

Pages that refer to this page: umad_set_grh_net(3)