Manual Pages for UNIX Operating System command usage for man ddi_mmap_get_model

Kernel Functions for Drivers               ddi_mmap_get_model(9F)



NAME
     ddi_mmap_get_model -  return  data  model  type  of  current
     thread

SYNOPSIS
     #include 
     #include 



     uint_t ddi_mmap_get_model(void);


INTERFACE LEVEL
     Solaris DDI specific (Solaris DDI).

DESCRIPTION
     ddi_mmap_get_model() returns the C Language Type Model which
     the  current thread expects. ddi_mmap_get_model() is used in
     combination with ddi_model_convert_from(9F) in the  mmap(9E)
     driver  entry  point  to  determine  whether there is a data
     model mismatch between the current  thread  and  the  device
     driver.  The device driver might have to adjust the shape of
     data structures before exporting them to a user thread which
     supports a different data model.

RETURN VALUES
     DDI_MODEL_ILP32     Current thread  expects  32-bit  (ILP32)
                         semantics.


     DDI_MODEL_LP64      Current  thread  expects  64-bit  (LP64)
                         semantics.


     DDI_FAILURE         The  ddi_mmap_get_model()  function  was
                         not   called  from  the  mmap(9E)  entry
                         point.


CONTEXT
     The ddi_mmap_get_model() function can only  be  called  from
     the mmap(9E) driver entry point.

EXAMPLES
     Example 1 : Using ddi_mmap_get_model()


     The following is an example of the mmap(9E) entry point  and
     how  to support 32-bit and 64-bit applications with the same
     device driver.




SunOS 5.11           Last change: 8 Feb 2001                    1






Kernel Functions for Drivers               ddi_mmap_get_model(9F)



       struct data32 {
               int len;
               caddr32_t addr;
       };

       struct data {
               int len;
               caddr_t addr;
       };
       xxmmap(dev_t dev, off_t off, int prot) {
               struct data dtc; /* a local copy for clash resolution */
               struct data *dp = (struct data *)shared_area;

               switch (ddi_model_convert_from(ddi_mmap_get_model())) {
               case DDI_MODEL_ILP32:
               {
                       struct data32 *da32p;

                       da32p = (struct data32 *)shared_area;
                       dp = &dtc;
                       dp->len = da32p->len;
                       dp->address = da32->address;
                       break;
               }
               case DDI_MODEL_NONE:
                       break;
               }
               /* continues along using dp */
              ...
       }


SEE ALSO
     mmap(9E), ddi_model_convert_from(9F)


     Writing Device Drivers


















SunOS 5.11           Last change: 8 Feb 2001                    2