ibv_bind_mw(3) — Linux manual page


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

NAME         top

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

SYNOPSIS         top

       #include <infiniband/verbs.h>

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

DESCRIPTION         top

       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

       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         top

       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         top

       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         top

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

AUTHORS         top

       Majd Dibbiny <majd@mellanox.com>

       Yishai Hadas <yishaih@mellanox.com>

COLOPHON         top

       This page is part of the rdma-core (RDMA Core Userspace Libraries and
       Daemons) project.  Information about the project can be found at 
       ⟨https://github.com/linux-rdma/rdma-core⟩.  If you have a bug report
       for this manual page, send it to linux-rdma@vger.kernel.org.  This
       page was obtained from the project's upstream Git repository
       ⟨https://github.com/linux-rdma/rdma-core.git⟩ on 2020-06-09.  (At
       that time, the date of the most recent commit that was found in the
       repository was 2020-06-05.)  If you discover any rendering problems
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       of the original manual page), send a mail to man-pages@man7.org

libibverbs                       2016-02-02                   IBV_BIND_MW(3)

Pages that refer to this page: ibv_alloc_mw(3)ibv_dealloc_mw(3)