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IBV_POST_RECV(3)	Libibverbs Programmer's	Manual	      IBV_POST_RECV(3)

NAME
       ibv_post_recv - post a list of work requests (WRs) to a receive queue

SYNOPSIS
       #include	<infiniband/verbs.h>

       int ibv_post_recv(struct	ibv_qp *qp, struct ibv_recv_wr *wr,
			 struct	ibv_recv_wr **bad_wr);

DESCRIPTION
       ibv_post_recv()	posts  the linked list of work requests	(WRs) starting
       with wr to the receive queue of the queue pair qp.  It stops processing
       WRs  from  this list at the first failure (that can be detected immedi-
       ately while requests are	being posted), and  returns  this  failing  WR
       through bad_wr.

       The  argument  wr  is  an  ibv_recv_wr  struct,	as defined in <infini-
       band/verbs.h>.

       struct ibv_recv_wr {
	       uint64_t		       wr_id;	  /* User defined WR ID	*/
	       struct ibv_recv_wr     *next;	  /* Pointer to	next WR	in list, NULL if last WR */
	       struct ibv_sge	      *sg_list;	  /* Pointer to	the s/g	array */
	       int		       num_sge;	  /* Size of the s/g array */
       };

       struct ibv_sge {
	       uint64_t		       addr;	  /* Start address of the local	memory buffer */
	       uint32_t		       length;	  /* Length of the buffer */
	       uint32_t		       lkey;	  /* Key of the	local Memory Region */
       };

RETURN VALUE
       ibv_post_recv() returns 0 on success, or	the value of errno on  failure
       (which indicates	the failure reason).

NOTES
       The buffers used	by a WR	can only be safely reused after	WR the request
       is fully	executed and a work completion has  been  retrieved  from  the
       corresponding completion	queue (CQ).

       If  the	QP  qp is associated with a shared receive queue, you must use
       the function ibv_post_srq_recv(), and not  ibv_post_recv(),  since  the
       QP's own	receive	queue will not be used.

       If  a WR	is being posted	to a UD	QP, the	Global Routing Header (GRH) of
       the incoming message will be placed in the first	40 bytes of  the  buf-
       fer(s)  in the scatter list.  If	no GRH is present in the incoming mes-
       sage, then the first bytes will be undefined.  This means that  in  all
       cases,  the actual data of the incoming message will start at an	offset
       of 40 bytes into	the buffer(s) in the scatter list.

SEE ALSO
       ibv_create_qp(3),	ibv_post_send(3),	 ibv_post_srq_recv(3),
       ibv_poll_cq(3)

AUTHORS
       Dotan Barak <dotanba@gmail.com>

libibverbs			  2006-10-31		      IBV_POST_RECV(3)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | NOTES | SEE ALSO | AUTHORS

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