mapdev_dup(9E)

NAME

     mapdev_dup - device mapping duplication entry point

SYNOPSIS

     #include <sys/sunddi.h>

      int  prefix  mapdev_dup(ddi_mapdev_handle_t  handle,   void
     *devprivate,     ddi_mapdev_handle_t     new_handle,    void
     **new_devprivatep);

INTERFACE LEVEL

     Solaris DDI specific (Solaris DDI).

PARAMETERS

     handle
           The handle of the mapping that is being duplicated.

     devprivate
           Driver private mapping data from the mapping  that  is
           being duplicated.

     new_handle
           An opaque pointer to the duplicated device mapping.

     new_devprivatep
           A pointer to be filled  in  by  the  driver  with  the
           driver  private mapping data for the duplicated device
           mapping.

DESCRIPTION

     Future releases of Solaris will provide  this  function  for
     binary   and  source  compatibility.  However, for increased
     functionality,    use     devmap_dup(9E)    instead.     See
     devmap_dup(9E) for details.

     mapdev_dup() is called when a device mapping  is  duplicated
     such  as  through  fork(2). mapdev_dup() is expected to gen-
     erate new driver private data for the new mapping,  and  set
     new_devprivatep  to point to it. new_handle is the handle of
     the new mapped object.

     A non-zero return value from  mapdev_dup()  will  cause  the
     corresponding operation, such as fork() to fail.

RETURN VALUES

     mapdev_dup() returns  0 for success or the appropriate error
     number on failure.

CONTEXT

     This function is called from user context only.

EXAMPLES

     static int
     xxmapdev_dup(ddi_mapdev_handle_t handle, void *devprivate,
         ddi_mapdev_handle_t new_handle, void **new_devprivate)
     {
          struct xxpvtdata    *pvtdata;
          /* Allocate a new private data structure */
          pvtdata = kmem_alloc(sizeof (struct xxpvtdata), KM_SLEEP);
          /* Copy the old data to the new - device dependent*/
          ...
          /* Return the new data */
          *new_pvtdata = pvtdata;
          return (0);
     }

SEE ALSO

     fork(2),   mmap(2),   mapdev_access(9E),    mapdev_free(9E),
     segmap(9E),     ddi_mapdev(9F),    ddi_mapdev_intercept(9F),
     ddi_mapdev_nointercept(9F), ddi_mapdev_ctl(9S)

     Writing Device Drivers