ibv_create_qp(3) — Linux manual page


IBV_CREATE_QP(3)     Libibverbs Programmer's Manual     IBV_CREATE_QP(3)

NAME         top

       ibv_create_qp, ibv_destroy_qp - create or destroy a queue pair

SYNOPSIS         top

       #include <infiniband/verbs.h>

       struct ibv_qp *ibv_create_qp(struct ibv_pd *pd,
                                    struct ibv_qp_init_attr *qp_init_attr);

       int ibv_destroy_qp(struct ibv_qp *qp);

DESCRIPTION         top

       ibv_create_qp() creates a queue pair (QP) associated with the
       protection domain pd.  The argument qp_init_attr is an
       ibv_qp_init_attr struct, as defined in <infiniband/verbs.h>.

       struct ibv_qp_init_attr {
               void                   *qp_context;     /* Associated context of the QP */
               struct ibv_cq          *send_cq;        /* CQ to be associated with the Send Queue (SQ) */
               struct ibv_cq          *recv_cq;        /* CQ to be associated with the Receive Queue (RQ) */
               struct ibv_srq         *srq;            /* SRQ handle if QP is to be associated with an SRQ, otherwise NULL */
               struct ibv_qp_cap       cap;            /* QP capabilities */
               enum ibv_qp_type        qp_type;        /* QP Transport Service Type: IBV_QPT_RC, IBV_QPT_UC, IBV_QPT_UD, IBV_QPT_RAW_PACKET or IBV_QPT_DRIVER */
               int                     sq_sig_all;     /* If set, each Work Request (WR) submitted to the SQ generates a completion entry */

       struct ibv_qp_cap {
               uint32_t                max_send_wr;    /* Requested max number of outstanding WRs in the SQ */
               uint32_t                max_recv_wr;    /* Requested max number of outstanding WRs in the RQ */
               uint32_t                max_send_sge;   /* Requested max number of scatter/gather (s/g) elements in a WR in the SQ */
               uint32_t                max_recv_sge;   /* Requested max number of s/g elements in a WR in the RQ */
               uint32_t                max_inline_data;/* Requested max number of data (bytes) that can be posted inline to the SQ, otherwise 0 */

       The function ibv_create_qp() will update the qp_init_attr->cap
       struct with the actual QP values of the QP that was created; the
       values will be greater than or equal to the values requested.

       ibv_destroy_qp() destroys the QP qp.

RETURN VALUE         top

       ibv_create_qp() returns a pointer to the created QP, or NULL if
       the request fails.  Check the QP number (qp_num) in the returned

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

NOTES         top

       ibv_create_qp() will fail if a it is asked to create QP of a type
       other than IBV_QPT_RC or IBV_QPT_UD associated with an SRQ.

       The attributes max_recv_wr and max_recv_sge are ignored by
       ibv_create_qp() if the QP is to be associated with an SRQ.

       ibv_destroy_qp() fails if the QP is attached to a multicast

       IBV_QPT_DRIVER does not represent a specific service and is used
       for vendor specific QP logic.

SEE ALSO         top

       ibv_alloc_pd(3), ibv_modify_qp(3), ibv_query_qp(3)

AUTHORS         top

       Dotan Barak <dotanba@gmail.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 2023-12-22.  (At
       that time, the date of the most recent commit that was found in
       the repository was 2023-12-20.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
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       (which is not part of the original manual page), send a mail to

libibverbs                     2006-10-31               IBV_CREATE_QP(3)

Pages that refer to this page: ibv_alloc_pd(3)ibv_create_cq(3)ibv_create_cq_ex(3)ibv_modify_qp(3)ibv_modify_qp_rate_limit(3)ibv_open_qp(3)ibv_post_recv(3)ibv_post_send(3)ibv_post_srq_recv(3)ibv_query_port(3)ibv_query_qp(3)rdma_create_qp(3)rdma_destroy_qp(3)