-*- nroff -*-

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

 #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" ); 

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_XRC */
int sq_sig_all; /* If set, each Work Request (WR) submitted to the SQ generates a completion entry */
struct ibv_xrc_domain *xrc_domain; /* XRC domain the QP will be associated with (valid only for IBV_QPT_XRC QP), otherwise NULL */
};
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 \s-1QP\s0 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 <dotanb@mellanox.co.il>