+<h2>vm_machine_attribute</h2>
+<hr>
+<p>
+<strong>Function</strong> - Get/set the target memory region's special attributes.
+<h3>SYNOPSIS</h3>
+<pre>
+<strong>kern_return_t vm_machine_attribute</strong>
+ <strong>(vm_task_t</strong> <var>target_task</var>,
+ <strong>vm_address_t</strong> <var>address</var>,
+ <strong>vm_size_t</strong> <var>size</var>,
+ <strong>vm_machine_attribute_t</strong> <var>attribute</var>,
+ <strong>vm_machine_attribute_val_t</strong> <var>value</var><strong>);</strong>
+</pre>
+<h3>PARAMETERS</h3>
+<dl>
+<p>
+<dt> <var>target_task</var>
+<dd>
+[in task send right]
+The port for the task in whose address space the
+memory object is to be manipulated.
+<p>
+<dt> <var>address</var>
+<dd>
+[in scalar]
+The starting address for the memory region. The granularity
+of rounding of this value to page boundaries is implementation
+dependent.
+<p>
+<dt> <var>size</var>
+<dd>
+[in scalar]
+The number of bytes in the region. The granularity of
+rounding of this value to page boundaries is implementation dependent.
+<p>
+<dt> <var>attribute</var>
+<dd>
+[in scalar]
+The name of the attribute to be get/set. Possible values are:
+<dl>
+<p>
+<dt> <strong>MATTR_CACHE</strong>
+<dd>
+Cachability. Aside from the generic values listed below, the
+following special values are defined:
+<dl>
+<p>
+<dt> <strong>MATTR_VAL_CACHE_FLUSH</strong>
+<dd>
+Flush from all caches
+<p>
+<dt> <strong>MATTR_VAL_DCACHE_FLUSH</strong>
+<dd>
+Flush from data caches
+<p>
+<dt> <strong>MATTR_VAL_ICACHE_FLUSH</strong>
+<dd>
+Flush from instruction caches
+</dl>
+<p>
+<dt> <strong>MATTR_MIGRATE</strong>
+<dd>
+Migratability.
+<p>
+<dt> <strong>MATTR_REPLICATE</strong>
+<dd>
+Replicability.
+</dl>
+<p>
+<dt> <var>value</var>
+<dd>
+[pointer to in/out scalar]
+The new value for the attribute. The old value
+is also returned in this variable. The new value can be a specific value
+listed above, or one of the following generic values:
+<dl>
+<p>
+<dt> <strong>MATTR_VAL_OFF</strong>
+<dd>
+Turn attribute off.
+<p>
+<dt> <strong>MATTR_VAL_ON</strong>
+<dd>
+Turn attribute on.
+<p>
+<dt> <strong>MATTR_VAL_GET</strong>
+<dd>
+No change, just return current value.
+</dl>
+</dl>
+<h3>DESCRIPTION</h3>
+<p>
+The <strong>vm_machine_attribute</strong> function gets and sets special
+attributes of the
+memory region implemented by the underlying <strong>pmap</strong> module. These attributes
+are properties such as cachability, migratability and replicability.
+The behavior of this function is machine dependent.
+<h3>NOTES</h3>
+<p>
+This interface is machine word length specific because of the virtual address
+parameter.
+<h3>RETURN VALUES</h3>
+<dl>
+<p>
+<dt> <strong>KERN_INVALID_ADDRESS</strong>
+<dd>
+The address is illegal or specifies a non-allocated region.
+</dl>
+<h3>RELATED INFORMATION</h3>
+<p>
+Functions:
+<a href="vm_wire.html"><strong>vm_wire</strong></a>.