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1*1031c584SApple OSS Distributions<h2>memory_object_data_unavailable</h2>
2*1031c584SApple OSS Distributions<hr>
3*1031c584SApple OSS Distributions<p>
4*1031c584SApple OSS Distributions<strong>Function</strong> - Instruct kernel to zero-fill pages as requested data does not exist.
5*1031c584SApple OSS Distributions<h3>SYNOPSIS</h3>
6*1031c584SApple OSS Distributions<pre>
7*1031c584SApple OSS Distributions<strong>kern_return_t   memory_object_data_unavailable</strong>
8*1031c584SApple OSS Distributions                <strong>(memory_object_control_t</strong>         <var>memory_control</var>,
9*1031c584SApple OSS Distributions                 <strong>vm_offset_t</strong>                             <var>offset</var>,
10*1031c584SApple OSS Distributions                 <strong>vm_size_t</strong>                                 <var>size</var><strong>);</strong>
11*1031c584SApple OSS Distributions</pre>
12*1031c584SApple OSS Distributions<h3>PARAMETERS</h3>
13*1031c584SApple OSS Distributions<dl>
14*1031c584SApple OSS Distributions<p>
15*1031c584SApple OSS Distributions<dt> <var>memory_control</var>
16*1031c584SApple OSS Distributions<dd>
17*1031c584SApple OSS Distributions[in memory-cache-control send right]
18*1031c584SApple OSS DistributionsThe memory cache control port
19*1031c584SApple OSS Distributionsto be used by the memory manager for cache management requests.
20*1031c584SApple OSS DistributionsThis port is provided by the kernel in a <strong>memory_object_init</strong> or a
21*1031c584SApple OSS Distributions<strong>memory_object_create</strong> call.
22*1031c584SApple OSS Distributions<p>
23*1031c584SApple OSS Distributions<dt> <var>offset</var>
24*1031c584SApple OSS Distributions<dd>
25*1031c584SApple OSS Distributions[in scalar]
26*1031c584SApple OSS DistributionsThe offset within the memory object, in bytes.
27*1031c584SApple OSS Distributions<p>
28*1031c584SApple OSS Distributions<dt> <var>size</var>
29*1031c584SApple OSS Distributions<dd>
30*1031c584SApple OSS Distributions[in scalar]
31*1031c584SApple OSS DistributionsThe number of bytes of data (starting at <var>offset</var>).  The number
32*1031c584SApple OSS Distributionsmust convert to an integral number of memory object pages.
33*1031c584SApple OSS Distributions</dl>
34*1031c584SApple OSS Distributions<h3>DESCRIPTION</h3>
35*1031c584SApple OSS Distributions<p>
36*1031c584SApple OSS DistributionsThe <strong>memory_object_data_unavailable</strong> function indicates
37*1031c584SApple OSS Distributionsthat the memory
38*1031c584SApple OSS Distributionsmanager cannot provide the kernel with the data requested for
39*1031c584SApple OSS Distributionsthe given region.
40*1031c584SApple OSS DistributionsInstead, the kernel should provide the data for this region.
41*1031c584SApple OSS Distributions<p>
42*1031c584SApple OSS DistributionsA memory manager can use this call in any of the following situations:
43*1031c584SApple OSS Distributions<ul>
44*1031c584SApple OSS Distributions<li>
45*1031c584SApple OSS DistributionsWhen the object was created by the kernel
46*1031c584SApple OSS Distributions(via <strong>memory_object_create</strong>) and
47*1031c584SApple OSS Distributionsthe kernel has not yet provided data for the region (via either
48*1031c584SApple OSS Distributions<strong>memory_object_data_initialize</strong> or <strong>memory_object_data_return</strong>).
49*1031c584SApple OSS DistributionsIn this case, the
50*1031c584SApple OSS Distributionsobject is a temporary memory object; the memory manager is the default
51*1031c584SApple OSS Distributionsmemory manager; and the kernel should provide zero-filled pages for the
52*1031c584SApple OSS Distributionsobject.
53*1031c584SApple OSS Distributions     <p>
54*1031c584SApple OSS Distributions<li>
55*1031c584SApple OSS DistributionsWhen the object is a normal user-created memory object.  In this case, the
56*1031c584SApple OSS Distributionskernel should provide zero-filled pages for the region.
57*1031c584SApple OSS Distributions</ul>
58*1031c584SApple OSS Distributions<h3>RETURN VALUES</h3>
59*1031c584SApple OSS Distributions<p>
60*1031c584SApple OSS DistributionsOnly generic errors apply.
61*1031c584SApple OSS Distributions<h3>RELATED INFORMATION</h3>
62*1031c584SApple OSS Distributions<p>
63*1031c584SApple OSS DistributionsFunctions:
64*1031c584SApple OSS Distributions<a href="memory_object_create.html"><strong>memory_object_create</strong></a>,
65*1031c584SApple OSS Distributions<a href="memory_object_data_error.html"><strong>memory_object_data_error</strong></a>,
66*1031c584SApple OSS Distributions<a href="memory_object_data_request.html"><strong>memory_object_data_request</strong></a>,
67*1031c584SApple OSS Distributions<a href="memory_object_data_supply.html"><strong>memory_object_data_supply</strong></a>.
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