1<h2>memory_object_data_return</h2> 2<hr> 3<p> 4<strong>Server Interface</strong> - Return memory object data to the appropriate memory manager. 5<h3>SYNOPSIS</h3> 6<pre> 7<strong>kern_return_t memory_object_data_return</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>pointer_t</strong> <var>data</var>, 12 <strong>boolean_t</strong> <var>dirty</var>, 13 <strong>boolean_t</strong> <var>kernel_copy</var><strong>);</strong> 14 15 16<strong>kern_return_t seqnos_memory_object_data_return</strong> 17 <strong>(memory_object_t</strong> <var>memory_object</var>, 18 <strong>mach_port_seqno_t</strong> <var>seqno</var>, 19 <strong>memory_object_control_t</strong> <var>memory_control</var>, 20 <strong>vm_offset_t</strong> <var>offset</var>, 21 <strong>pointer_t</strong> <var>data</var>, 22 <strong>boolean_t</strong> <var>dirty</var>, 23 <strong>boolean_t</strong> <var>kernel_copy</var><strong>);</strong> 24</pre> 25<h3>PARAMETERS</h3> 26<dl> 27<p> 28<dt> <var>memory_object</var> 29<dd> 30[in abstract-memory-object (receive) right] 31The abstract memory 32object port that represents the memory object data. 33<p> 34<dt> <var>seqno</var> 35<dd> 36[in scalar] 37The sequence number of this message relative to the abstract 38memory object port. 39<p> 40<dt> <var>memory_control</var> 41<dd> 42[in memory-cache-control send right] 43The memory cache control port 44to be used for a response by the memory manager. If the memory 45object has been supplied to more than one kernel, this parameter 46identifies the kernel that is making the call. 47<p> 48<dt> <var>offset</var> 49<dd> 50[in scalar] 51The offset within the memory object. 52<p> 53<dt> <var>data</var> 54<dd> 55[in pointer to dynamic array of bytes] 56The data that has been evicted 57from the physical memory cache. 58<p> 59<dt> <var>dirty</var> 60<dd> 61[in scalar] 62If <strong>TRUE</strong>, the pages returned have been modified. 63<p> 64<dt> <var>kernel_copy</var> 65<dd> 66[in scalar] 67If <strong>TRUE</strong>, the kernel has kept a copy of the page. 68</dl> 69<h3>DESCRIPTION</h3> 70<p> 71A <strong>memory_object_data_return</strong> function is called as the 72result of a kernel 73message providing the memory manager with data that has been evicted from the 74physical memory cache. 75<p> 76The kernel writes back only data that has been modified or is precious. When 77the memory manager no longer needs the data (for example, after the data has 78been written to permanent storage), it should use <strong>vm_deallocate</strong> 79to release the 80memory resources. 81<h3>NOTES</h3> 82<p> 83The kernel can flush clean (that is, un-modified) non-precious 84pages at its own 85discretion. As a result, the memory manager cannot rely on the 86kernel to keep a 87copy of its data or even to provide notification that its data 88has been discarded. 89<p> 90The kernel may re-request the returned data at any time following this message 91(including immediately). 92<h3>RETURN VALUES</h3> 93<p> 94Only generic errors apply. 95<h3>RELATED INFORMATION</h3> 96<p> 97Functions: 98<a href="memory_object_data_supply.html"><strong>memory_object_data_supply</strong></a>, 99<a href="vm_deallocate.html"><strong>vm_deallocate</strong></a>, 100<a href="memory_object_synchronize.html"><strong>memory_object_synchronize</strong></a>, 101<a href="memory_object_server.html"><strong>memory_object_server</strong></a>, 102<a href="SMO_server.html"><strong>seqnos_memory_object_server</strong></a>. 103