Index for Section 9r

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trunc_page(9r)
NAME
  trunc_page - General: Truncates the specified address

SYNOPSIS
  #include <mach/vm_param.h>

  vm_offset_t trunc_page(
	  vm_offset_t address );

ARGUMENTS
  address
      Specifies the address that is being truncated to a page boundary.

DESCRIPTION
  The trunc_page routine truncates the specified address to be aligned on a
  page boundary. 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 trunc_page in preparation for doing a DMA
  operation on 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 trunc_page routine returns an address truncated to a page boundary.

SEE ALSO
  Routines: current_task(9r), round_page(9r), vm_map_pageable(9r)

Index for Section 9r

Alphabetical listing for T

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