Current File : //usr/share/man/man9f/ddi_mmap_get_model.9f

'\" te
.\"  Copyright (c) 2001 Sun Microsystems, Inc.  All Rights Reserved.
.TH ddi_mmap_get_model 9F  "8 Feb 2001" "SunOS 5.11" "Kernel Functions for Drivers"
.SH NAME
ddi_mmap_get_model \- return data model type of current thread
.SH SYNOPSIS
.LP
.nf
#include <sys/ddi.h> 
#include <sys/sunddi.h>

\fBuint_t\fR \fBddi_mmap_get_model\fR(\fBvoid\fR);
.fi

.SH INTERFACE LEVEL
.sp
.LP
Solaris DDI specific (Solaris DDI).
.SH DESCRIPTION
.sp
.LP
\fBddi_mmap_get_model()\fR returns the \fIC\fR Language Type Model which the current thread expects. \fBddi_mmap_get_model()\fR is used in combination with \fBddi_model_convert_from\fR(9F) in the \fBmmap\fR(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.
.SH RETURN VALUES
.sp
.ne 2
.mk
.na
\fB\fBDDI_MODEL_ILP32\fR \fR
.ad
.RS 20n
.rt  
Current thread expects 32-bit \fI(ILP32)\fR semantics.
.RE

.sp
.ne 2
.mk
.na
\fB\fBDDI_MODEL_LP64\fR \fR
.ad
.RS 20n
.rt  
Current thread expects 64-bit \fI(LP64)\fR semantics.
.RE

.sp
.ne 2
.mk
.na
\fB\fBDDI_FAILURE\fR \fR
.ad
.RS 20n
.rt  
The \fBddi_mmap_get_model()\fR function was not called from the \fBmmap\fR(9E) entry point.
.RE

.SH CONTEXT
.sp
.LP
The \fBddi_mmap_get_model()\fR function can only be called from the \fBmmap\fR(9E) driver entry point.
.SH EXAMPLES
.LP
\fBExample 1 \fR: Using \fBddi_mmap_get_model()\fR
.sp
.LP
The following is an example of the \fBmmap\fR(9E) entry point and how to support 32-bit and 64-bit applications with the same device driver.

.sp
.in +2
.nf
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 */
       \&.\|.\|.
}
.fi
.in -2

.SH SEE ALSO
.sp
.LP
\fBmmap\fR(9E), \fBddi_model_convert_from\fR(9F) 
.sp
.LP
\fIWriting Device Drivers for Oracle Solaris 11.2\fR