Creates or destroys a queue pair (QP).
#include <rdma/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 <rdma/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; | /*Not Supported*/ | |
| struct ibv_qp_cap | cap; | /*QP capabilities*/ | |
| enum ibv_qp_type | qp_type; | /*QP Transport Service Type: IBV_QPT_RC,*/ | |
| int | sq_sig_all; | /*If set, each Work Request (WR) submitted to the SQ*/ | |
| /*generates a completion entry */ | |||
| struct ibv_xrc_domain | xrc_domain; | /*Not supported*/ | |
| 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() updates 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.
| pd | struct ibv_pd from ibv_alloc_pd. |
| qp_init_attr | Initial attributes of queue pair. |
| qp_init_attr | Actual values are filled in. |
ibv_create_qp() returns a pointer to the created QP on success, or NULL if the request fails.
ibv_destroy_qp() returns 0 on success, or the value of errno on failure (which indicates the failure reason).