Index for Section 9r

Alphabetical listing for I

Bottom of page

IS_KSEG_VA(9r)
NAME
  IS_KSEG_VA, IS_SEG0_VA, IS_SEG1_VA - General: Determine if the specified
  address is located in the kernel-unmapped address space, the user-mapped
  address space, and the kernel-mapped address space.

SYNOPSIS
  void IS_KSEG_VA(
	  unsigned long addr );

  void IS_SEG0_VA(
	  unsigned long addr );

  void IS_SEG1_VA(
	  unsigned long addr );

ARGUMENTS
  addr
      Specifies the virtual address.

DESCRIPTION
  The IS_KSEG_VA routine determines if the specified address is located in
  the kernel-unmapped address space. The IS_SEG0_VA routine determines if the
  specified address is located in the user-mapped address space. The
  IS_SEG1_VA routine determines if the specified address is located in the
  kernel-mapped address space.

RETURN VALUES
  None

EXAMPLE
  The following code fragment shows a call to IS_KSEG_VA:

       .
       .
       .

       caddr_t virt_addr;  [1]
       unsigned phys_addr; [2]

       .
       .
       .

	   if(IS_KSEG_VA(virt_addr)) { [3]
	       phys_addr = KSEG_TO_PHYS(virt_addr); [4]

       .
       .
       .

   1.  Declares a variable to store the user buffer's virtual address.

   2.  Declares a variable to store the physical address returned by
       KSEG_TO_PHYS.

   3.  Before calling KSEG_TO_PHYS, calls IS_KSEG_VA to determine if the
       virtual address is from the kernel-unmapped address space.

   4.  If the virtual address is from the kernel-unmapped address space, then
       calls KSEG_TO_PHYS to convert the address to a corresponding physical
       address.

SEE ALSO
  Routines: KSEG_TO_PHYS(9r), PHYS_TO_KSEG(9r)

Index for Section 9r

Alphabetical listing for I

Top of page