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1*699cd480SApple OSS Distributions<h2>default_pager_add_segment</h2>
2*699cd480SApple OSS Distributions<hr>
3*699cd480SApple OSS Distributions<p>
4*699cd480SApple OSS Distributions<strong>Server Interface</strong> - Add additional backing storage for a default pager.
5*699cd480SApple OSS Distributions<h3>SYNOPSIS</h3>
6*699cd480SApple OSS Distributions<pre>
7*699cd480SApple OSS Distributions<strong>#include&lt mach/default_pager_object.h&gt</strong>
8*699cd480SApple OSS Distributions
9*699cd480SApple OSS Distributions<strong>kern_return_t   default_pager_add_segment</strong>
10*699cd480SApple OSS Distributions                <strong>(mach_port_t</strong>                      <var>backing_store</var>,
11*699cd480SApple OSS Distributions                 <strong>mach_port_t</strong>                             <var>device</var>,
12*699cd480SApple OSS Distributions                 <strong>recnum_t</strong>                                <var>offset</var>,
13*699cd480SApple OSS Distributions                 <strong>recnum_t</strong>                                 <var>count</var>,
14*699cd480SApple OSS Distributions                 <strong>int</strong>                                <var>record_size</var><strong>);</strong>
15*699cd480SApple OSS Distributions</pre>
16*699cd480SApple OSS Distributions<h3>PARAMETERS</h3>
17*699cd480SApple OSS Distributions<dl>
18*699cd480SApple OSS Distributions<p>
19*699cd480SApple OSS Distributions<dt> <var>backing_store</var>
20*699cd480SApple OSS Distributions<dd>
21*699cd480SApple OSS Distributions[in backing store (receive) right] The backing store port.
22*699cd480SApple OSS Distributions<p>
23*699cd480SApple OSS Distributions<dt> <var>device</var>
24*699cd480SApple OSS Distributions<dd>
25*699cd480SApple OSS Distributions[in device port] The port for the device containing the backing storage
26*699cd480SApple OSS Distributionspartition.
27*699cd480SApple OSS Distributions<p>
28*699cd480SApple OSS Distributions<dt> <var>offset</var>
29*699cd480SApple OSS Distributions<dd>
30*699cd480SApple OSS Distributions[in scalar] The offset, in <var>record_size units</var>, to the beginning of the
31*699cd480SApple OSS Distributionsbacking storage on the device.
32*699cd480SApple OSS Distributions<p>
33*699cd480SApple OSS Distributions<dt> <var>count</var>
34*699cd480SApple OSS Distributions<dd>
35*699cd480SApple OSS Distributions[in scalar] The number of <var>record_size</var> units
36*699cd480SApple OSS Distributionsin the partition/segment.
37*699cd480SApple OSS Distributions<p>
38*699cd480SApple OSS Distributions<dt> <var>record_size</var>
39*699cd480SApple OSS Distributions<dd>
40*699cd480SApple OSS Distributions[in scalar] The size, in bytes, of the storage device record.
41*699cd480SApple OSS Distributions</dl>
42*699cd480SApple OSS Distributions<h3>DESCRIPTION</h3>
43*699cd480SApple OSS Distributions<p>
44*699cd480SApple OSS DistributionsThe <strong>default_pager_add_segment</strong> function is called to add a partition to
45*699cd480SApple OSS Distributionsa default pager's backing storage (i.e. expand the amount of backing
46*699cd480SApple OSS Distributionsstorage available to a memory manager). The kernel does not make
47*699cd480SApple OSS Distributionsthis call itself (which is why it can be a synchronous call); this
48*699cd480SApple OSS Distributionsrequest is only issued by tasks holding the backing store port,
49*699cd480SApple OSS Distributionscreated with <strong>default_pager_backing_store_create</strong>, for a default memory
50*699cd480SApple OSS Distributionsmanager.
51*699cd480SApple OSS DistributionsThe result is that the pager may use count records on device starting
52*699cd480SApple OSS Distributionsat offset for paging, and each record is record_size bytes in length
53*699cd480SApple OSS Distributions(note that the device_* calls are, or can be, record oriented).
54*699cd480SApple OSS Distributions<h3>RETURN VALUES</h3>
55*699cd480SApple OSS Distributions<dl>
56*699cd480SApple OSS Distributions<p>
57*699cd480SApple OSS Distributions<dt> <strong>KERN_FAILURE</strong>
58*699cd480SApple OSS Distributions<dd>
59*699cd480SApple OSS DistributionsThe default pager does not support this operation.
60*699cd480SApple OSS Distributions<p>
61*699cd480SApple OSS Distributions<dt> <strong>KERN_INVALID_ARGUMENT</strong>
62*699cd480SApple OSS Distributions<dd>
63*699cd480SApple OSS DistributionsThe <var>backing_store</var> port does not represent a valid backing store or the
64*699cd480SApple OSS Distributionsspecified segment overlaps an existing partition.
65*699cd480SApple OSS Distributions<p>
66*699cd480SApple OSS Distributions<dt> <strong>KERN_RESOURCE_SHORTAGE</strong>
67*699cd480SApple OSS Distributions<dd>
68*699cd480SApple OSS DistributionsThe default pager is unable to allocate internal resources
69*699cd480SApple OSS Distributions     to manage the new backing storage.
70*699cd480SApple OSS Distributions<p>
71*699cd480SApple OSS Distributions<dt> <strong>KERN_SUCCESS</strong>
72*699cd480SApple OSS Distributions<dd>
73*699cd480SApple OSS DistributionsThe operation was successful.
74*699cd480SApple OSS Distributions</dl>
75*699cd480SApple OSS Distributions<h3>RELATED INFORMATION</h3>
76*699cd480SApple OSS Distributions<p>
77*699cd480SApple OSS DistributionsFunctions:
78*699cd480SApple OSS Distributions<a href="DP_backing_store_create.html"><strong>default_pager_backing_store_create</strong></a>,
79*699cd480SApple OSS Distributions<a href="DP_backing_store_delete.html"><strong>default_pager_backing_store_delete</strong></a>,
80*699cd480SApple OSS Distributions<a href="DP_backing_store_info.html"><strong>default_pager_backing_store_info</strong></a>.
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