Kernel Functions for Drivers hat_getkpfnum(9F)
NAME
hat_getkpfnum - get page frame number for kernel address
SYNOPSIS
#include
#include
#include
pfn_t hat_getkpfnum(caddr_t addr);
INTERFACE LEVEL
This interface is obsolete. A driver devmap(9E) entry point should be provided instead.PARAMETERS
addr The kernel virtual address for which the page frame number is to be returned.DESCRIPTION
hat_getkpfnum() returns the page frame number corresponding
to the kernel virtual address, addr. addr must be a kernel virtual address which maps to devicememory. ddi_map_regs(9F) can be used to obtain this address.
For example, ddi_map_regs(9F) can be called in the driver's
attach(9E) routine. The resulting kernel virtual address canbe saved by the driver (see ddi_soft_state(9F)) and used in
mmap(9E). The corresponding ddi_unmap_regs(9F) call can be
made in the driver's detach(9E) routine. Refer to mmap(9E) for more information.RETURN VALUES
The page frame number corresponding to the valid, device-
mapped virtual address addr. Otherwise the return value is undefined.CONTEXT
hat_getkpfnum() can be called only from user or kernel con-
text.ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:SunOS 5.11 Last change: 13 June 2004 1
Kernel Functions for Drivers hat_getkpfnum(9F)
____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Interface Stability | Obsolete ||_____________________________|_____________________________|
SEE ALSO
attach(9E), detach(9E), devmap(9E), mmap(9E),ddi_map_regs(9F), ddi_soft_state(9F), ddi_unmap_regs(9F)
Writing Device Drivers NOTES For some devices, mapping device memory in the driver's attach(9E) routine and unmapping device memory in the driver's detach(9E) routine is a sizeable drain on system resources. This is especially true for devices with a large amount of physical address space. Refer to mmap(9E) for alternative methods.SunOS 5.11 Last change: 13 June 2004 2