NAME
  vtop - virtual to physical

SYNOPSIS
  vtop [-c [pid | taskp]] [-u|-k] address ...

DESCRIPTION
  This command translates a user or kernel virtual address to its physical
  address.  Also displayed is the PTE translation, the vm_area_struct data
  for user virtual addresses, the mem_map page data associated with the
  physical page, and the swap location or file location if the page is
  not mapped.  The -u and -k options specify that the address is a user
  or kernel virtual address; -u and -k are not necessary on processors whose
  virtual addresses self-define themselves as user or kernel.  User addresses
  are translated with respect to the current context unless the -c option
  is used.  Kernel virtual addresses are translated using the swapper_pg_dir
  as the base page directory unless the -c option is used.
 
   -u                 The address is a user virtual address; only required
                      on processors with overlapping user and kernel virtual
                      address spaces.
   -k                 The address is a kernel virtual address; only required
                      on processors with overlapping user and kernel virtual
                      address spaces.
   -c [pid | taskp]   Translate the virtual address from the page directory
                      of the specified PID or hexadecimal task_struct pointer.
                      However, if this command is invoked from "foreach vtop",
                      the pid or taskp argument should NOT be entered; the
                      address will be translated using the page directory of
                      each task specified by "foreach".
   address            A hexadecimal user or kernel virtual address.

EXAMPLES
  Translate user virtual address 80b4000:

    crash> vtop 80b4000
    VIRTUAL   PHYSICAL
    80b4000   660f000
    
    PAGE DIRECTORY: c37f0000
      PGD: c37f0080 => e0d067
      PMD: c37f0080 => e0d067
      PTE: c0e0d2d0 => 660f067
     PAGE: 660f000
 
      PTE    PHYSICAL  FLAGS
    660f067   660f000  (PRESENT|RW|USER|ACCESSED|DIRTY)
    
      VMA      START      END      FLAGS  FILE
    c773daa0   80b4000   810c000    77
    
      PAGE    PHYSICAL   INODE     OFFSET  CNT FLAGS
    c0393258   660f000         0     17000  1  uptodate
    
  Translate kernel virtual address c806e000, first using swapper_pg_dir
  as the page directory base, and secondly, using the page table base
  of PID 1359:

    crash> vtop c806e000
    VIRTUAL   PHYSICAL
    c806e000  2216000
    
    PAGE DIRECTORY: c0101000
      PGD: c0101c80 => 94063
      PMD: c0101c80 => 94063
      PTE: c00941b8 => 2216063
     PAGE: 2216000
 
      PTE    PHYSICAL  FLAGS
    2216063   2216000  (PRESENT|RW|ACCESSED|DIRTY)
    
      PAGE    PHYSICAL   INODE     OFFSET  CNT FLAGS
    c02e9370   2216000         0         0  1  
    
    crash> vtop -c 1359 c806e000
    VIRTUAL   PHYSICAL
    c806e000  2216000
    
    PAGE DIRECTORY: c5caf000
      PGD: c5cafc80 => 94063
      PMD: c5cafc80 => 94063
      PTE: c00941b8 => 2216063
     PAGE: 2216000
    
      PTE    PHYSICAL  FLAGS
    2216063   2216000  (PRESENT|RW|ACCESSED|DIRTY)
 
      PAGE    PHYSICAL   INODE     OFFSET  CNT FLAGS
    c02e9370   2216000         0         0  1  
    
  Determine swap location of user virtual address 40104000:

    crash> vtop 40104000
    VIRTUAL   PHYSICAL
    40104000  (not mapped)
    
    PAGE DIRECTORY: c40d8000
      PGD: c40d8400 => 6bbe067
      PMD: c40d8400 => 6bbe067
      PTE: c6bbe410 => 58bc00  
 
     PTE      SWAP     OFFSET
    58bc00  /dev/sda8   22716
    
      VMA      START      END     FLAGS  FILE
    c7200ae0  40104000  40b08000    73   
 
    SWAP: /dev/sda8  OFFSET: 22716