round_page(9r) [osf1 man page]

round_page(9r)															    round_page(9r)

NAME

       round_page - General: Rounds the specified address

SYNOPSIS

       #include <mach/vm_param.h>

       vm_offset_t round_page(
	       vm_offset_t address );

ARGUMENTS

       Specifies the address (or byte count) that is being rounded.

DESCRIPTION

       The  round_page	routine rounds the specified address (or byte count) to a multiple of the page size. For example, round_page would round a
       1-byte count to be equal to the size of one page.  This routine shields the driver writer from having to know the page size of the  system,
       which  could  vary in different CPU architectures and on different CPU types within the same architecture. Typically, a device driver calls
       round_page in preparation for doing a DMA operation to a user's buffer. The value returned by this routine is  used  in	the  call  to  the
       vm_map_pageable routine. To use this routine, the driver writer must include the <mach/vm_param.h> header file in the driver.

RETURN VALUES

       The round_page routine returns the rounded address or byte count.

SEE ALSO

       Routines: current_task(9r), trunc_page(9r), vm_map_pageable(9r)

																    round_page(9r)

hat_getkpfnum(9F)					   Kernel Functions for Drivers 					 hat_getkpfnum(9F)

NAME

       hat_getkpfnum - get page frame number for kernel address

SYNOPSIS

       #include <sys/types.h>
       #include <sys/ddi.h>
       #include <sys/sunddi.h>

       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       This interface is obsolete.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 device memory. 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 can be 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 context.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      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							   13 June 2004 						 hat_getkpfnum(9F)