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, resources 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 represents 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 address 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>