ddi_mmap_get_model(9f)

1ddi_mmap_get_model(9F)   Kernel Functions for Drivers   ddi_mmap_get_model(9F)
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NAME

6       ddi_mmap_get_model - return data model type of current thread
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SYNOPSIS

9       #include <sys/ddi.h>
10       #include <sys/sunddi.h>
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14       uint_t ddi_mmap_get_model(void);
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INTERFACE LEVEL

18       Solaris DDI specific (Solaris DDI).
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DESCRIPTION

21       ddi_mmap_get_model()  returns  the C Language Type Model which the cur‐
22       rent thread expects. ddi_mmap_get_model() is used in  combination  with
23       ddi_model_convert_from(9F) in the mmap(9E) driver entry point to deter‐
24       mine whether there is a data model mismatch between the current  thread
25       and the device driver. The device driver might have to adjust the shape
26       of data structures before exporting them to a user  thread  which  sup‐
27       ports a different data model.
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RETURN VALUES

30       DDI_MODEL_ILP32     Current thread expects 32-bit (ILP32) semantics.
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33       DDI_MODEL_LP64      Current thread expects 64-bit (LP64) semantics.
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36       DDI_FAILURE         The  ddi_mmap_get_model()  function  was not called
37                           from the mmap(9E) entry point.
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CONTEXT

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

45       Example 1 : Using ddi_mmap_get_model()
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48       The following is an example of the mmap(9E) entry point and how to sup‐
49       port 32-bit and 64-bit applications with the same device driver.
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52         struct data32 {
53                 int len;
54                 caddr32_t addr;
55         };
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57         struct data {
58                 int len;
59                 caddr_t addr;
60         };
61         xxmmap(dev_t dev, off_t off, int prot) {
62                 struct data dtc; /* a local copy for clash resolution */
63                 struct data *dp = (struct data *)shared_area;
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65                 switch (ddi_model_convert_from(ddi_mmap_get_model())) {
66                 case DDI_MODEL_ILP32:
67                 {
68                         struct data32 *da32p;
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70                         da32p = (struct data32 *)shared_area;
71                         dp = &dtc;
72                         dp->len = da32p->len;
73                         dp->address = da32->address;
74                         break;
75                 }
76                 case DDI_MODEL_NONE:
77                         break;
78                 }
79                 /* continues along using dp */
80                ...
81         }
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