centos man page for ibv_create_qp

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

NAME
       ibv_create_qp, ibv_destroy_qp - create or destroy a queue pair (QP)

SYNOPSIS
       #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
       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 or IBV_QPT_RAW_PACKET */
	       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 SQ */
	       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
       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 QP.

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

NOTES
       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 group.

SEE ALSO
       ibv_alloc_pd(3), ibv_modify_qp(3), ibv_query_qp(3)

AUTHORS
       Dotan Barak <dotanba@gmail.com>

libibverbs							    2006-10-31							  IBV_CREATE_QP(3)