]> git.saurik.com Git - apple/xnu.git/blob - osfmk/man/DP_backing_store_info.html
xnu-2422.1.72.tar.gz
[apple/xnu.git] / osfmk / man / DP_backing_store_info.html
1 <h2>default_pager_backing_store_info</h2>
2 <hr>
3 <p>
4 <strong>Server Interface</strong> - Return information about a backing storage object.
5 <h3>SYNOPSIS</h3>
6 <pre>
7 <strong>#include&lt default_pager/mach/default_pager_types.h&gt</strong>
8
9 <strong>kern_return_t default_pager_backing_store_info</strong>
10 <strong>(mach_port_t</strong> <var>backing_store</var>,
11 <strong>backing_store_flavor_t</strong> <var>flavor</var>,
12 <strong>backing_store_info_t</strong> <var>info</var>,
13 <strong>mach_msg_type_number_t</strong> <var>size</var><strong>);</strong>
14 </pre>
15 <h3>PARAMETERS</h3>
16 <dl>
17 <p>
18 <dt> <var>backing_store</var>
19 <dd>
20 [in backing store (receive) right] The backing store port for which
21 information is desired.
22 <p>
23 <dt> <var>flavor</var>
24 <dd>
25 [in scalar] The type of information to be returned. Valid values are:
26 <p>
27 <dt> <var>BACKING_STORE_BASIC_INFO</var>
28 <dd>
29 Statistical and space used/available information. It includes
30 the priority and cluster size that was provided in the
31 default_pager_backing_store_create call.
32 <p>
33 <dt> <var>info</var>
34 <dd>
35 [pointer to in structure] The data structure that will be filled in with the
36 information provided for the requested flavor.
37 <p>
38 <dt> <var>size</var>
39 <dd>
40 [pointer to in/out scalar] On input, the maximum size of the info data
41 structure; on output, the actual size of the returned data.
42 </dl>
43 <h3>DESCRIPTION</h3>
44 <p>
45 The <strong>default_pager_backing_store_info</strong> function is called to obtain
46 information about a backing storage object created by
47 <strong>default_pager_backing_store_create</strong>. The kernel does not make this call
48 itself (which is why it can be a synchronous call); this request is
49 only issued by tasks holding the backing store port, created with
50 <strong>default_pager_backing_store_create</strong>, for a default memory manager.
51 <h3>RETURN VALUES</h3>
52 <dl>
53 <p>
54 <dt> <strong>KERN_FAILURE</strong>
55 <dd>
56 The default pager does not support this operation.
57 <p>
58 <dt> <strong>KERN_INVALID_ARGUMENT</strong>
59 <dd>
60 The backing_store port does not represent a valid backing store, flavor
61 is not valid, or size is not the size for the requested flavor.
62 <p>
63 <dt> <strong>KERN_SUCCESS</strong>
64 <dd>
65 The operation was successful.
66 </dl>
67 <h3>RELATED INFORMATION</h3>
68 <p>
69 Functions:
70 <a href="DP_backing_store_create.html"><strong>default_pager_backing_store_create</strong></a>,
71 <a href="DP_backing_store_delete.html"><strong>default_pager_backing_store_delete</strong></a>.
72 <p>
73 Data Structures:
74 backing_store_basic_info.