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efadv_query_cq(3) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | SEE ALSO | NOTES | AUTHORS | COLOPHON 

EFADV_QUERY_CQ(3)        EFA Direct Verbs Manual        EFADV_QUERY_CQ(3)

NAME         top

       efadv_query_cq - Query EFA specific Completion Queue attributes

SYNOPSIS         top

              #include <infiniband/efadv.h>

              int efadv_query_cq(struct ibv_cq *ibvcq, struct efadv_cq_attr *attr,
                                 uint32_t inlen);

DESCRIPTION         top

       efadv_query_cq() queries device-specific Completion Queue
       attributes.

       Compatibility is handled using the comp_mask and inlen fields.

              struct efadv_cq_attr {
                  uint64_t comp_mask;
                  uint8_t *buffer;
                  uint32_t entry_size;
                  uint32_t num_entries;
                  uint32_t *doorbell;
              };

       inlen  In: Size of struct efadv_cq_attr.

       comp_mask
              Compatibility mask.

       buffer Completion queue buffer.

       entry_size
              Size of each completion queue entry.

       num_entries
              Maximal number of entries in the completion queue.

       doorbell
              Reverse doorbell used to update the device of polled
              entries and to request notifications.  NULL when not in use
              for this Completion Queue.

RETURN VALUE         top

       efadv_query_cq() returns 0 on success, or the value of errno on
       failure (which indicates the failure reason).

SEE ALSO         top

       efadv(7)

NOTES         top

       • Compatibility mask (comp_mask) is an out field and currently has
         no values.

AUTHORS         top

       Michael Margolin ⟨mrgolin@amazon.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 2026-01-16.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2026-01-15.)  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

efa                             2025-04-15              EFADV_QUERY_CQ(3)

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