osfmk/man/memory_object_synchronize.html

   1 <h2>memory_object_synchronize</h2>
   2 <hr>
   3 <p>
   4 <strong>Server Interface</strong> - Forward a client's request to synchronize data with its image in backing store.
   5 <h3>SYNOPSIS</h3>
   6 <pre>
   7 <strong>kern_return_t   memory_object_synchronize</strong>
   8                 <strong>(memory_object_t</strong>                  <var>memory_object</var>,
   9                  <strong>memory_object_control_t</strong>         <var>memory_control</var>,
  10                  <strong>vm_offset_t</strong>                             <var>offset</var>,
  11                  <strong>vm_offset_t</strong>                             <var>length</var>,
  12                  <strong>memory_object</strong>                       <var>sync_flags</var><strong>);</strong>
  13
  14
  15 <strong>kern_return_t   seqnos_memory_object_synchronize</strong>
  16                 <strong>(memory_object_t</strong>                  <var>memory_object</var>,
  17                  <strong>mach_port_seqno_t</strong>                        <var>seqno</var>,
  18                  <strong>memory_object_control_t</strong>         <var>memory_control</var>,
  19                  <strong>vm_offset_t</strong>                             <var>offset</var>,
  20                  <strong>vm_offset_t</strong>                             <var>length</var>,
  21                  <strong>memory_object</strong>                       <var>sync_flags</var><strong>);</strong>
  22 </pre>
  23 <h3>PARAMETERS</h3>
  24 <dl>
  25 <p>
  26 <dt> <var>memory_object</var>
  27 <dd>
  28 [in abstract-memory-object (receive) right]
  29 The abstract memory
  30 object port that represents the memory object data.
  31 <p>
  32 <dt> <var>seqno</var>
  33 <dd>
  34 [in scalar]
  35 The sequence number of this message relative to the abstract
  36 memory object port.
  37 <p>
  38 <dt> <var>memory_control</var>
  39 <dd>
  40 [in memory-cache-control send right]
  41 The memory cache control port
  42 to be used for a response by the memory manager.  If the memory
  43 object has been supplied to more than one kernel, this parameter
  44 identifies the kernel that is making the call.
  45 <p>
  46 <dt> <var>offset</var>
  47 <dd>
  48 [in scalar]
  49 The offset within the memory object.
  50 <p>
  51 <dt> <var>length</var>
  52 <dd>
  53 [in scalar]
  54 The number of bytes cleaned or flushed, starting at <var>offset</var>.
  55 The number converts to an integral number of virtual pages.
  56 <p>
  57 <dt> <var>sync_flags</var>
  58 <dd>
  59 [in scalar]
  60 The bit-wise OR of flags affecting the synchronization.
  61 <dl>
  62 <p>
  63 <dt> <strong>VM_SYNC_INVALIDATE</strong>
  64 <dd>
  65 Flushes pages in the range.  Only precious pages are returned
  66 to the memory manager.
  67 <p>
  68 <dt> <strong>VM_SYNC_SYNCHRONOUS</strong>
  69 <dd>
  70 Writes dirty and precious pages back to the memory manager,
  71 waits for pages to reach backing storage.
  72 <p>
  73 <dt> <strong>VM_SYNC_ASYNCHRONOUS</strong>
  74 <dd>
  75 Writes dirty and precious pages back to the memory manager,
  76 returns without waiting for pages to reach backing storage.
  77 </dl>
  78 </dl>
  79 <h3>DESCRIPTION</h3>
  80 <p>
  81 A <strong>memory_object_synchronize</strong> function is called as the
  82 result of a kernel
  83 message indicating that a client wishes to synchronize the contents
  84 of a range of a
  85 memory object with its backing storage image.  This message would have been
  86 preceded by <strong>memory_object_data_return</strong> messages cleaning
  87 or flushing the
  88 specified range.
  89 <p>
  90 Depending on the client's supplied <var>sync_flags</var>, the manager waits
  91 for the pages
  92 to reach the desired state and then replies with
  93 <strong>memory_object_synchronize_completed</strong> at which time the
  94 client returns from its <strong>vm_msync</strong> call.  Multiple
  95 synchronize requests may be outstanding at a time but they will not overlap.
  96 <h3>RETURN VALUES</h3>
  97 <p>
  98 Only generic errors apply.
  99 <h3>RELATED INFORMATION</h3>
 100 <p>
 101 Functions:
 102 <a href="vm_msync.html"><strong>vm_msync</strong></a>,
 103 <a href="MO_SY_completed.html"><strong>memory_object_synchronize_completed</strong></a>,
 104 <a href="memory_object_data_return.html"><strong>memory_object_data_return</strong></a>,
 105 <a href="memory_object_server.html"><strong>memory_object_server</strong></a>,
 106 <a href="SMO_server.html"><strong>seqnos_memory_object_server</strong></a>.