NAME

       ibv_rereg_mr - re-register a memory region (MR)

SYNOPSIS

              #include <infiniband/verbs.h>

              int ibv_rereg_mr(struct ibv_mr *mr,
                               int flags,
                               struct ibv_pd *pd,
                               void *addr,
                               size_t length,
                               int access);

DESCRIPTION

       ibv_rereg_mr()  Modifies  the  attributes  of an existing memory region (MR) mr.  Conceptually, this call
       performs the functions deregister memory region followed by register memory region.  Where possible,  re‐
       sources are reused instead of deallocated and reallocated.

       flags  is  a  bit-mask  used to indicate which of the following properties of the memory region are being
       modified.  Flags should be a combination (bit field) of:

       IBV_REREG_MR_CHANGE_TRANSLATION
              Change translation (location and length)

       IBV_REREG_MR_CHANGE_PD
              Change protection domain

       IBV_REREG_MR_CHANGE_ACCESS
              Change access flags

       When IBV_REREG_MR_CHANGE_PD is used, pd represents the new PD this MR should be registered to.

       When IBV_REREG_MR_CHANGE_TRANSLATION is used, addr.  represents the virtual address (user-space  pointer)
       of the new MR, while length represents its length.

       The  access and other flags are represented in the field access.  This field describes the desired memory
       protection attributes; it is either 0 or the bitwise OR of one or more of ibv_access_flags.

RETURN VALUE

       ibv_rereg_mr() returns 0 on success, otherwise an error has occurred, enum  ibv_rereg_mr_err_code  repre‐
       sents the error as of below.

       IBV_REREG_MR_ERR_INPUT - Old MR is valid, an input error was detected by libibverbs.

       IBV_REREG_MR_ERR_DONT_FORK_NEW - Old MR is valid, failed via don’t fork on new address range.

       IBV_REREG_MR_ERR_DO_FORK_OLD - New MR is valid, failed via do fork on old address range.

       IBV_REREG_MR_ERR_CMD - MR shouldn’t be used, command error.

       IBV_REREG_MR_ERR_CMD_AND_DO_FORK_NEW - MR shouldn’t be used, command error, invalid fork state on new ad‐
       dress range.

NOTES

       Even on a failure, the user still needs to call ibv_dereg_mr on this MR.

SEE ALSO

       ibv_dereg_mr(3), ibv_reg_mr(3)

AUTHORS

       Matan Barak <matanb@mellanox.com>, Yishai Hadas <yishaih@mellanox.com>

libibverbs                                         2016-03-13                                    IBV_REREG_MR(3)