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#ifndef SPDK_RDMA_H
#define SPDK_RDMA_H

#include <infiniband/verbs.h>
#include <rdma/rdma_cma.h>
#include <rdma/rdma_verbs.h>

struct spdk_rdma_qp_init_attr {
	void		       *qp_context;
	struct ibv_cq	       *send_cq;
	struct ibv_cq	       *recv_cq;
	struct ibv_srq	       *srq;
	struct ibv_qp_cap	cap;
	struct ibv_pd	       *pd;
};

struct spdk_rdma_send_wr_list {
	struct ibv_send_wr	*first;
	struct ibv_send_wr	*last;
};

struct spdk_rdma_qp {
	struct ibv_qp *qp;
	struct rdma_cm_id *cm_id;
	struct spdk_rdma_send_wr_list send_wrs;
};

/**
 * Create RDMA provider specific qpair
 * \param cm_id Pointer to RDMACM cm_id
 * \param qp_attr Pointer to qpair init attributes
 * \return Pointer to a newly created qpair on success or NULL on failure
 */
struct spdk_rdma_qp *spdk_rdma_qp_create(struct rdma_cm_id *cm_id,
		struct spdk_rdma_qp_init_attr *qp_attr);

/**
 * Accept a connection request. Called by the passive side (NVMEoF target)
 * \param spdk_rdma_qp Pointer to a qpair
 * \param conn_param Optional information needed to establish the connection
 * \return 0 on success, errno on failure
 */
int spdk_rdma_qp_accept(struct spdk_rdma_qp *spdk_rdma_qp, struct rdma_conn_param *conn_param);

/**
 * Complete the connection process, must be called by the active
 * side (NVMEoF initiator) upon receipt RDMA_CM_EVENT_CONNECT_RESPONSE
 * \param spdk_rdma_qp Pointer to a qpair
 * \return 0 on success, errno on failure
 */
int spdk_rdma_qp_complete_connect(struct spdk_rdma_qp *spdk_rdma_qp);

/**
 * Destroy RDMA provider specific qpair
 * \param spdk_rdma_qp Pointer to qpair to be destroyed
 */
void spdk_rdma_qp_destroy(struct spdk_rdma_qp *spdk_rdma_qp);

/**
 * Disconnect a connection and transition assoiciated qpair to error state.
 * Generates RDMA_CM_EVENT_DISCONNECTED on both connection sides
 * \param spdk_rdma_qp Pointer to qpair to be destroyed
 */
int spdk_rdma_qp_disconnect(struct spdk_rdma_qp *spdk_rdma_qp);

/**
 * Append the given send wr structure to the qpair's outstanding sends list.
 * This function accepts either a single Work Request or the first WR in a linked list.
 *
 * \param spdk_rdma_qp Pointer to SPDK RDMA qpair
 * \param first Pointer to the first Work Request
 * \return true if there were no outstanding WRs before, false otherwise
 */
bool spdk_rdma_qp_queue_send_wrs(struct spdk_rdma_qp *spdk_rdma_qp, struct ibv_send_wr *first);

/**
 * Submit all queued Work Request
 * \param spdk_rdma_qp Pointer to SPDK RDMA qpair
 * \param bad_wr Stores a pointer to the first failed WR if this function return nonzero value
 * \return 0 on succes, errno on failure
 */
int spdk_rdma_qp_flush_send_wrs(struct spdk_rdma_qp *spdk_rdma_qp, struct ibv_send_wr **bad_wr);

#endif /* SPDK_RDMA_H */