projects / apple / xnu.git / blame
| Commit | Line | Data |
|---|---|---|
| 13fec989 A |
1 | <h2>default_pager_add_segment</h2> |
| 2 | <hr> | |
| 3 | <p> | |
| 4 | <strong>Server Interface</strong> - Add additional backing storage for a default pager. | |
| 5 | <h3>SYNOPSIS</h3> | |
| 6 | <pre> | |
| 7 | <strong>#include< mach/default_pager_object.h></strong> | |
| 8 | ||
| 9 | <strong>kern_return_t default_pager_add_segment</strong> | |
| 10 | <strong>(mach_port_t</strong> <var>backing_store</var>, | |
| 11 | <strong>mach_port_t</strong> <var>device</var>, | |
| 12 | <strong>recnum_t</strong> <var>offset</var>, | |
| 13 | <strong>recnum_t</strong> <var>count</var>, | |
| 14 | <strong>int</strong> <var>record_size</var><strong>);</strong> | |
| 15 | </pre> | |
| 16 | <h3>PARAMETERS</h3> | |
| 17 | <dl> | |
| 18 | <p> | |
| 19 | <dt> <var>backing_store</var> | |
| 20 | <dd> | |
| 21 | [in backing store (receive) right] The backing store port. | |
| 22 | <p> | |
| 23 | <dt> <var>device</var> | |
| 24 | <dd> | |
| 25 | [in device port] The port for the device containing the backing storage | |
| 26 | partition. | |
| 27 | <p> | |
| 28 | <dt> <var>offset</var> | |
| 29 | <dd> | |
| 30 | [in scalar] The offset, in <var>record_size units</var>, to the beginning of the | |
| 31 | backing storage on the device. | |
| 32 | <p> | |
| 33 | <dt> <var>count</var> | |
| 34 | <dd> | |
| 35 | [in scalar] The number of <var>record_size</var> units | |
| 36 | in the partition/segment. | |
| 37 | <p> | |
| 38 | <dt> <var>record_size</var> | |
| 39 | <dd> | |
| 40 | [in scalar] The size, in bytes, of the storage device record. | |
| 41 | </dl> | |
| 42 | <h3>DESCRIPTION</h3> | |
| 43 | <p> | |
| 44 | The <strong>default_pager_add_segment</strong> function is called to add a partition to | |
| 45 | a default pager's backing storage (i.e. expand the amount of backing | |
| 46 | storage available to a memory manager). The kernel does not make | |
| 47 | this call itself (which is why it can be a synchronous call); this | |
| 48 | request is only issued by tasks holding the backing store port, | |
| 49 | created with <strong>default_pager_backing_store_create</strong>, for a default memory | |
| 50 | manager. | |
| 51 | The result is that the pager may use count records on device starting | |
| 52 | at offset for paging, and each record is record_size bytes in length | |
| 53 | (note that the device_* calls are, or can be, record oriented). | |
| 54 | <h3>RETURN VALUES</h3> | |
| 55 | <dl> | |
| 56 | <p> | |
| 57 | <dt> <strong>KERN_FAILURE</strong> | |
| 58 | <dd> | |
| 59 | The default pager does not support this operation. | |
| 60 | <p> | |
| 61 | <dt> <strong>KERN_INVALID_ARGUMENT</strong> | |
| 62 | <dd> | |
| 63 | The <var>backing_store</var> port does not represent a valid backing store or the | |
| 64 | specified segment overlaps an existing partition. | |
| 65 | <p> | |
| 66 | <dt> <strong>KERN_RESOURCE_SHORTAGE</strong> | |
| 67 | <dd> | |
| 68 | The default pager is unable to allocate internal resources | |
| 69 | to manage the new backing storage. | |
| 70 | <p> | |
| 71 | <dt> <strong>KERN_SUCCESS</strong> | |
| 72 | <dd> | |
| 73 | The operation was successful. | |
| 74 | </dl> | |
| 75 | <h3>RELATED INFORMATION</h3> | |
| 76 | <p> | |
| 77 | Functions: | |
| 78 | <a href="DP_backing_store_create.html"><strong>default_pager_backing_store_create</strong></a>, | |
| 79 | <a href="DP_backing_store_delete.html"><strong>default_pager_backing_store_delete</strong></a>, | |
| 80 | <a href="DP_backing_store_info.html"><strong>default_pager_backing_store_info</strong></a>. |