xref: /xnu-8796.101.5/iokit/DriverKit/IOWorkGroup.iig (revision aca3beaa3dfbd42498b42c5e5ce20a938e6554e5)
1/*
2 * Copyright (c) 2021 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
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27 */
28
29#ifndef _IOKIT_UIOWORKGROUP_H
30#define _IOKIT_UIOWORKGROUP_H
31
32#include <DriverKit/OSObject.iig>
33#include <DriverKit/IOUserClient.iig>
34
35enum {
36	kIOWorkGroupMaxNameLength = 64,
37};
38
39/*!
40 * @class IOWorkGroup
41 *
42 * @abstract
43 * Workgroups allow multiple threads to coordinate activities for realtime operations.
44 *
45 * @discussion
46 *
47 * Applications that open user clients to a DriverKit driver can send a workgroup to use in the driver.
48 *
49 * The application will have to first create an workgroup object. The application then should copy the
50 * workgroup port with os_workgroup_copy_port(). To send the workgroup port to the driver, use:
51 *
52 * const char * name = "Work Group Name"; // This must match the name the driver used in IOWorkGroup::Create().
53 * kern_return_t ret = IOConnectTrap3(connect, // user client connection (io_connect_t)
54 *                                    1, // specifies event link configuration trap
55 *                                    (uintptr_t)name,
56 *                                    (uintptr_t)strlen(name),
57 *                                    (uintptr_t)wgPort // port from os_workgroup_copy_port
58 *                                    );
59 *
60 * Once the workgroup port has been sent to the driver, the driver should be notified with a user-defined external method
61 * or other existing signaling mechanism.
62 */
63class NATIVE KERNEL IOWorkGroup : public OSObject
64{
65public:
66
67	virtual bool
68	init() override;
69
70	virtual void
71	free() override;
72
73    /*!
74     * @brief       Create an IOWorkGroup object. This object is not functional until a workgroup port has been set.
75     * @param       name        Name of the workgroup
76     * @param       userClient  Userclient to create the workgroup in. The DriverKit runtime will retain the userclient, and will
77     *                          release it in Invalidate() or when the IOWorkGroup is freed.
78     * @param       workgroup   Created IOWorkGroup with +1 retain count to be released by the caller.
79     * @return      kIOReturnSuccess on success. See IOReturn.h for error codes.
80     */
81	static kern_return_t
82	Create(OSString * name, IOUserClient * userClient, IOWorkGroup ** workgroup) LOCAL;
83
84#if DRIVERKIT_PRIVATE
85
86    /*!
87     * @brief       Set the port for this workgroup. This should not be called directly.
88     * @param       port Workgroup port
89     * @return      kIOReturnSuccess on success. See IOReturn.h for error codes.
90     */
91    virtual kern_return_t
92    SetWorkGroupPort(mach_port_t port PORTCOPYSEND) LOCAL;
93
94#endif /* DRIVERKIT_PRIVATE */
95
96    /*!
97     * @brief       Get the size of the workgroup token.
98     * @discussion  Join() and Leave() require the caller to pass a token. This token should be allocated by the caller, and freed when
99     *              no longer needed. Use this method to determine how much memory to allocate for the token.
100     * @return      Workgroup token size
101     */
102    size_t
103    GetTokenSize() LOCALONLY;
104
105    /*!
106     * @brief       Join the workgroup.
107     * @discussion  Before calling this method, the caller must allocate a token. This token must be passed to this method. When leaving
108     *              a workgroup with Leave(), use the same token that was passed to Join().
109     * @param       token  The workgroup token.
110     * @return      kIOReturnSuccess on success. See IOReturn.h for error codes.
111     */
112    kern_return_t
113    Join(void * token) LOCALONLY;
114
115    /*!
116     * @brief       Leave the workgroup.
117     * @discussion  The workgroup must have been joined with Join(). Use the same token in Join() for this method.
118     * @param       token  The workgroup token.
119     * @return      kIOReturnSuccess on success. See IOReturn.h for error codes.
120     */
121    kern_return_t
122    Leave(void * token) LOCALONLY;
123
124    /*!
125     * @brief       Invalidate the IOWorkGroup.
126     * @discussion  This releases the kernel reference to the IOWorkGroup, allowing the name to be used for a different
127     *              IOWorkGroup. This method should be called after the client has configured the eventlink with the IOConnectTrap
128     *              call. After invalidation, the IOWorkGroup can no longer be configured through the IOConnectTrap call. No other
129     *              functionality is affected.
130     * @return      kIOReturnSuccess on success. See IOReturn.h for error codes.
131     */
132    kern_return_t
133    Invalidate() LOCALONLY;
134
135#if DRIVERKIT_PRIVATE
136
137    virtual kern_return_t
138    InvalidateKernel(IOUserClient * client);
139
140#endif /* DRIVERKIT_PRIVATE */
141
142};
143
144#endif /* ! _IOKIT_UIOWORKGROUP_H */
145