1IBV_CREATE_QP(3) Libibverbs Programmer's Manual IBV_CREATE_QP(3)
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6 ibv_create_qp, ibv_destroy_qp - create or destroy a queue pair (QP)
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9 #include <infiniband/verbs.h>
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11 struct ibv_qp *ibv_create_qp(struct ibv_pd *pd,
12 struct ibv_qp_init_attr *qp_init_attr);
13 int ibv_destroy_qp(struct ibv_qp *qp);
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16 ibv_create_qp() creates a queue pair (QP) associated with the protec‐
17 tion domain pd. The argument qp_init_attr is an ibv_qp_init_attr
18 struct, as defined in <infiniband/verbs.h>.
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20 struct ibv_qp_init_attr {
21 void *qp_context; /* Associated context of the QP */
22 struct ibv_cq *send_cq; /* CQ to be associated with the Send Queue (SQ) */
23 struct ibv_cq *recv_cq; /* CQ to be associated with the Receive Queue (RQ) */
24 struct ibv_srq *srq; /* SRQ handle if QP is to be associated with an SRQ, otherwise NULL */
25 struct ibv_qp_cap cap; /* QP capabilities */
26 enum ibv_qp_type qp_type; /* QP Transport Service Type: IBV_QPT_RC, IBV_QPT_UC, or IBV_QPT_UD */
27 int sq_sig_all; /* If set, each Work Request (WR) submitted to the SQ generates a completion entry */
28 };
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30 struct ibv_qp_cap {
31 uint32_t max_send_wr; /* Requested max number of outstanding WRs in the SQ */
32 uint32_t max_recv_wr; /* Requested max number of outstanding WRs in the RQ */
33 uint32_t max_send_sge; /* Requested max number of scatter/gather (s/g) elements in a WR in the SQ */
34 uint32_t max_recv_sge; /* Requested max number of s/g elements in a WR in the SQ */
35 uint32_t max_inline_data;/* Requested max number of data (bytes) that can be posted inline to the SQ, otherwise 0 */
36 };
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38 The function ibv_create_qp() will update the qp_init_attr->cap struct
39 with the actual QP values of the QP that was created; the values will
40 be greater than or equal to the values requested.
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42 ibv_destroy_qp() destroys the QP qp.
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45 ibv_create_qp() returns a pointer to the created QP, or NULL if the
46 request fails. Check the QP number (qp_num) in the returned QP.
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48 ibv_destroy_qp() returns 0 on success, or the value of errno on failure
49 (which indicates the failure reason).
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52 ibv_create_qp() will fail if a it is asked to create QP of a type other
53 than IBV_QPT_RC or IBV_QPT_UD associated with an SRQ.
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55 The attributes max_recv_wr and max_recv_sge are ignored by ibv_cre‐
56 ate_qp() if the QP is to be associated with an SRQ.
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58 ibv_destroy_qp() fails if the QP is attached to a multicast group.
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61 ibv_alloc_pd(3), ibv_modify_qp(3), ibv_query_qp(3)
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64 Dotan Barak <dotanb@mellanox.co.il>
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68libibverbs 2006-10-31 IBV_CREATE_QP(3)