Create or destroy a queue pair (qp)
#include <infiniband/verbs.h>
struct ibv_qp *ibv_create_qp_ex(struct ibv_context *context,
struct ibv_qp_init_attr_ex *qp_init_attr);
int ibv_destroy_qp(struct ibv_qp *qp);
ibv_create_qp_ex() creates a queue pair (QP) associated with the protection domain pd. The argument qp_init_attr_ex is an ibv_qp_init_attr_ex struct, as defined in <infiniband/verbs.h>.
struct ibv_qp_init_attr_ex {
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 */
uint32_t comp_mask; /* Identifies valid fields */
struct ibv_pd *pd; /* PD to be associated with the QP */
struct ibv_xrcd *xrcd; /* XRC domain to be associated with the target QP */
enum ibv_qp_create_flags create_flags; /* Creation flags for this QP */
};
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_ex() will update the qp_init_attr_ex->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.
ibv_create_qp_ex() 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).
The attributes max_recv_wr and max_recv_sge are ignored by ibv_create_qp_ex() if the QP is to be associated with an SRQ.
ibv_destroy_qp() fails if the QP is attached to a multicast group.
Yishai Hadas <[email protected]>