bionic (3) ibv_bind_mw.3.gz

NAME

       ibv_bind_mw - post a request to bind a type 1 memory window to a memory region

SYNOPSIS

       #include <infiniband/verbs.h>

       int ibv_bind_mw(struct ibv_qp *qp, struct ibv_mw *mw,
                       struct ibv_mw_bind *mw_bind);

DESCRIPTION

       ibv_bind_mw()  posts to the queue pair qp a request to bind the memory window mw according to the details
       in mw_bind.

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

       struct ibv_mw_bind {
               uint64_t                     wr_id;           /* User defined WR ID */
               int                          send_flags;      /* Use ibv_send_flags */
               struct ibv_mw_bind_info      bind_info;       /* MW bind information */
       }

       struct ibv_mw_bind_info {
               struct ibv_mr                *mr;             /* The 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 */
       };

       The QP Transport Service Type must be either UC, RC or XRC_SEND for bind operations.

       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.

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

       The mw_access_flags define the allowed access to the MW after the  bind  completes  successfully.  It  is
       either 0 or the bitwise OR of one or more of the following flags:

       IBV_ACCESS_REMOTE_WRITE  Enable Remote Write Access. Requires local write access to the MR.

       IBV_ACCESS_REMOTE_READ Enable Remote Read Access

       IBV_ACCESS_REMOTE_ATOMIC  Enable  Remote  Atomic  Operation  Access  (if supported). Requires local write
       access to the MR.

       IBV_ACCESS_ZERO_BASED If set, the address set on the 'remote_addr' field on the WR will be an offset from
       the MW's start address.

RETURN VALUE

       ibv_bind_mw()  returns  0  on  success,  or  the  value  of errno on failure (which indicates the failure
       reason).  In case of a success, the R_key of the  memory  window  after  the  bind  is  returned  in  the
       mw_bind->mw->rkey field.

NOTES

       The bind does not complete when the function return - it is merely posted to the QP. The user should keep
       a copy of the old R_key, and fix the mw structure if the subsequent CQE for the bind operation  indicates
       a  failure. The user may safely send the R_key using a send request on the same QP, (based on QP ordering
       rules: a send after a bind request on the same QP are always ordered), but must not transfer  it  to  the
       remote in any other manner before reading a successful CQE.

       Note that for type 2 MW, one should directly post bind WR to the QP, using ibv_post_send.

SEE ALSO

       ibv_alloc_mw(3), ibv_post_send(3), ibv_poll_cq(3) ibv_reg_mr(3),

AUTHORS

       Majd Dibbiny <majd@mellanox.com>

       Yishai Hadas <yishaih@mellanox.com>