xref: /xnu-8792.81.2/osfmk/man/memory_object_data_unlock.html (revision 19c3b8c28c31cb8130e034cfb5df6bf9ba342d90)

<h2>memory_object_data_unlock</h2>
<hr>
<p>
<strong>Server Interface</strong> - Request that the memory manager change current access permission on the specified memory object's data.
<h3>SYNOPSIS</h3>
<pre>
<strong>kern_return_t   memory_object_data_unlock</strong>
                <strong>(memory_object_t</strong>                  <var>memory_object</var>,
                 <strong>memory_object_control_t</strong>         <var>memory_control</var>,
                 <strong>vm_offset_t</strong>                             <var>offset</var>,
                 <strong>vm_size_t</strong>                               <var>length</var>,
                 <strong>vm_prot_t</strong>                       <var>desired_access</var><strong>);</strong>


<strong>kern_return_t   seqnos_memory_object_data_unlock</strong>
                <strong>(memory_object_t</strong>                  <var>memory_object</var>,
                 <strong>mach_port_seqno_t</strong>                        <var>seqno</var>,
                 <strong>memory_object_control_t</strong>         <var>memory_control</var>,
                 <strong>vm_offset_t</strong>                             <var>offset</var>,
                 <strong>vm_size_t</strong>                               <var>length</var>,
                 <strong>vm_prot_t</strong>                       <var>desired_access</var><strong>);</strong>
</pre>
<h3>PARAMETERS</h3>
<dl>
<p>
<dt> <var>memory_object</var>
<dd>
[in abstract-memory-object (receive) right]
The abstract memory
object port that represents the memory object data.
<p>
<dt> <var>seqno</var>
<dd>
[in scalar]
The sequence number of this message relative to the abstract
memory object port.
<p>
<dt> <var>memory_control</var>
<dd>
[in memory-cache-control send right]
The memory cache control port
to be used for a response by the memory manager.  If the memory
object has been supplied to more than one kernel, this parameter
identifies the kernel that is making the call.
<p>
<dt> <var>offset</var>
<dd>
[in scalar]
The offset within the memory object.
<p>
<dt> <var>length</var>
<dd>
[in scalar]
The number of bytes to which the access applies, starting at
<var>offset</var>.  The number converts to an integral number of memory object
pages.
<p>
<dt> <var>desired_access</var>
<dd>
[in scalar]
The memory access modes requested for the cached data.
Possible values are obtained by or'ing together the following values:
<dl>
<p>
<dt> <strong>VM_PROT_READ</strong>
<dd>
Allows read access.
<p>
<dt> <strong>VM_PROT_WRITE</strong>
<dd>
Allows write access.
<p>
<dt> <strong>VM_PROT_EXECUTE</strong>
<dd>
Allows execute access.
</dl>
</dl>
<h3>DESCRIPTION</h3>
<p>
A <strong>memory_object_data_unlock</strong> function is called as the
result of a kernel
message requesting the memory manager to permit at least the
desired access to the
specified data cached by the kernel.  The memory manager is expected
to use the
<strong>memory_object_lock_request</strong> call in response.
<h3>RETURN VALUES</h3>
<p>
Only generic errors apply.
<h3>RELATED INFORMATION</h3>
<p>
Functions:
<a href="MO_lock_completed.html"><strong>memory_object_lock_completed</strong></a>,
<a href="memory_object_lock_request.html"><strong>memory_object_lock_request</strong></a>,
<a href="memory_object_server.html"><strong>memory_object_server</strong></a>,
<a href="SMO_server.html"><strong>seqnos_memory_object_server</strong></a>.