Provided by: libibverbs-dev_22.1-1_amd64 bug


       ibv_post_send - post a list of work requests (WRs) to a send queue


       #include <infiniband/verbs.h>

       int ibv_post_send(struct ibv_qp *qp, struct ibv_send_wr *wr,
                         struct ibv_send_wr **bad_wr);


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

       The argument wr is an ibv_send_wr struct, as defined in <infiniband/verbs.h>.

       struct ibv_send_wr {
               uint64_t                wr_id;                  /* User defined WR ID */
               struct ibv_send_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 */
               enum ibv_wr_opcode      opcode;                 /* Operation type */
               int                     send_flags;             /* Flags of the WR properties */
               union {
                       __be32                  imm_data;               /* Immediate data (in network byte order) */
                       uint32_t                invalidate_rkey;        /* Remote rkey to invalidate */
               union {
                       struct {
                               uint64_t        remote_addr;    /* Start address of remote memory buffer */
                               uint32_t        rkey;           /* Key of the remote Memory Region */
                       } rdma;
                       struct {
                               uint64_t        remote_addr;    /* Start address of remote memory buffer */
                               uint64_t        compare_add;    /* Compare operand */
                               uint64_t        swap;           /* Swap operand */
                               uint32_t        rkey;           /* Key of the remote Memory Region */
                       } atomic;
                       struct {
                               struct ibv_ah  *ah;             /* Address handle (AH) for the remote node address */
                               uint32_t        remote_qpn;     /* QP number of the destination QP */
                               uint32_t        remote_qkey;    /* Q_Key number of the destination QP */
                       } ud;
               } wr;
               union {
                       struct {
                               uint32_t remote_srqn;            /* Number of the remote SRQ */
                       } xrc;
               } qp_type;
               union {
                       struct {
                               struct ibv_mw            *mw;             /* Memory window (MW) of type 2 to bind */
                               uint32_t                 rkey;            /* The desired new rkey of the MW */
                               struct ibv_mw_bind_info  bind_info;       /* MW additional bind information */
                       } bind_mw;
                       struct {
                               void           *hdr;     /* Pointer address of inline header */
                               uint16_t       hdr_sz;   /* Inline header size */
                               uint16_t       mss; /* Maximum segment size for each TSO fragment */
                       } tso;

       struct ibv_mw_bind_info {
               struct ibv_mr            *mr;             /* The Memory region (MR) to bind the MW to */
               uint64_t                 addr;           /* The address the MW should start at */
               uint64_t                 length;          /* The length (in bytes) the MW should span */
               int                      mw_access_flags; /* Access flags to the MW. Use ibv_access_flags */

       struct ibv_sge {
               uint64_t                addr;                   /* Start address of the local memory buffer or number of bytes from the
                                                                  start of the MR for MRs which are IBV_ZERO_BASED */
               uint32_t                length;                 /* Length of the buffer */
               uint32_t                lkey;                   /* Key of the local Memory Region */

       Each QP Transport Service Type supports a  specific  set  of  opcodes,  as  shown  in  the
       following table:

       IBV_WR_SEND                 |     X      |     X      |     X      |         X        |         X
       IBV_WR_SEND_WITH_IMM        |     X      |     X      |     X      |         X        |
       IBV_WR_RDMA_WRITE           |            |     X      |     X      |         X        |
       IBV_WR_RDMA_WRITE_WITH_IMM  |            |     X      |     X      |         X        |
       IBV_WR_RDMA_READ            |            |            |     X      |         X        |
       IBV_WR_ATOMIC_CMP_AND_SWP   |            |            |     X      |         X        |
       IBV_WR_ATOMIC_FETCH_AND_ADD |            |            |     X      |         X        |
       IBV_WR_LOCAL_INV            |            |     X      |     X      |         X        |
       IBV_WR_BIND_MW              |            |     X      |     X      |         X        |
       IBV_WR_SEND_WITH_INV        |            |     X      |     X      |         X        |
       IBV_WR_TSO                  |     X      |            |            |                  |         X

       The attribute send_flags describes the properties of the WR. It is either 0 or the bitwise
       OR of one or more of the following flags:

       IBV_SEND_FENCE  Set the fence indicator. Valid only for QPs with  Transport  Service  Type

       IBV_SEND_SIGNALED   Set  the  completion  notification  indicator. Relevant only if QP was
       created with sq_sig_all=0

       IBV_SEND_SOLICITED  Set the solicited event indicator. Valid only for Send and RDMA  Write
       with immediate

       IBV_SEND_INLINE  Send data in given gather list as inline data
              in a send WQE.  Valid only for Send and RDMA Write.  The L_Key will not be checked.

       IBV_SEND_IP_CSUM  Offload the IPv4 and TCP/UDP checksum calculation.
              Valid  only  when device_cap_flags in device_attr indicates current QP is supported
              by checksum offload.


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


       The  user  should  not  alter  or  destroy  AHs associated with WRs until request is fully
       executed and a work completion has been retrieved from the corresponding completion  queue
       (CQ) to avoid unexpected behavior.

       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).
       However,  if  the IBV_SEND_INLINE flag was set, the buffer can be reused immediately after
       the call returns.


       ibv_create_qp(3), ibv_create_ah(3), ibv_post_recv(3), ibv_post_srq_recv(3), ibv_poll_cq(3)


       Dotan Barak <>

       Majd Dibbiny <>

       Yishai Hadas <>