binder.h revision df24a2eaa1e2de82d3033e1f37f17ad9c9a1c58e 
1/*
2 * Copyright (C) 2008 Google, Inc.
3 *
4 * Based on, but no longer compatible with, the original
5 * OpenBinder.org binder driver interface, which is:
6 *
7 * Copyright (c) 2005 Palmsource, Inc.
8 *
9 * This software is licensed under the terms of the GNU General Public
10 * License version 2, as published by the Free Software Foundation, and
11 * may be copied, distributed, and modified under those terms.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 * GNU General Public License for more details.
17 *
18 */
19
20#ifndef _UAPI_LINUX_BINDER_H
21#define _UAPI_LINUX_BINDER_H
22
23#include <linux/ioctl.h>
24
25#define B_PACK_CHARS(c1, c2, c3, c4) \
26	((((c1)<<24)) | (((c2)<<16)) | (((c3)<<8)) | (c4))
27#define B_TYPE_LARGE 0x85
28
29enum {
30	BINDER_TYPE_BINDER	= B_PACK_CHARS('s', 'b', '*', B_TYPE_LARGE),
31	BINDER_TYPE_WEAK_BINDER	= B_PACK_CHARS('w', 'b', '*', B_TYPE_LARGE),
32	BINDER_TYPE_HANDLE	= B_PACK_CHARS('s', 'h', '*', B_TYPE_LARGE),
33	BINDER_TYPE_WEAK_HANDLE	= B_PACK_CHARS('w', 'h', '*', B_TYPE_LARGE),
34	BINDER_TYPE_FD		= B_PACK_CHARS('f', 'd', '*', B_TYPE_LARGE),
35};
36
37enum {
38	FLAT_BINDER_FLAG_PRIORITY_MASK = 0xff,
39	FLAT_BINDER_FLAG_ACCEPTS_FDS = 0x100,
40};
41
42/*
43 * This is the flattened representation of a Binder object for transfer
44 * between processes.  The 'offsets' supplied as part of a binder transaction
45 * contains offsets into the data where these structures occur.  The Binder
46 * driver takes care of re-writing the structure type and data as it moves
47 * between processes.
48 */
49struct flat_binder_object {
50	/* 8 bytes for large_flat_header. */
51	__u32		type;
52	__u32		flags;
53
54	/* 8 bytes of data. */
55	union {
56		void __user	*binder;	/* local object */
57		__u32	    handle;		/* remote object */
58	};
59
60	/* extra data associated with local object */
61	void __user		*cookie;
62};
63
64/*
65 * On 64-bit platforms where user code may run in 32-bits the driver must
66 * translate the buffer (and local binder) addresses appropriately.
67 */
68
69struct binder_write_read {
70	size_t write_size;	/* bytes to write */
71	size_t write_consumed;	/* bytes consumed by driver */
72	unsigned long	write_buffer;
73	size_t read_size;	/* bytes to read */
74	size_t read_consumed;	/* bytes consumed by driver */
75	unsigned long	read_buffer;
76};
77
78/* Use with BINDER_VERSION, driver fills in fields. */
79struct binder_version {
80	/* driver protocol version -- increment with incompatible change */
81	__s32       protocol_version;
82};
83
84/* This is the current protocol version. */
85#define BINDER_CURRENT_PROTOCOL_VERSION 7
86
87#define BINDER_WRITE_READ		_IOWR('b', 1, struct binder_write_read)
88#define BINDER_SET_IDLE_TIMEOUT		_IOW('b', 3, __s64)
89#define BINDER_SET_MAX_THREADS		_IOW('b', 5, __u32)
90#define BINDER_SET_IDLE_PRIORITY	_IOW('b', 6, __s32)
91#define BINDER_SET_CONTEXT_MGR		_IOW('b', 7, __s32)
92#define BINDER_THREAD_EXIT		_IOW('b', 8, __s32)
93#define BINDER_VERSION			_IOWR('b', 9, struct binder_version)
94
95/*
96 * NOTE: Two special error codes you should check for when calling
97 * in to the driver are:
98 *
99 * EINTR -- The operation has been interupted.  This should be
100 * handled by retrying the ioctl() until a different error code
101 * is returned.
102 *
103 * ECONNREFUSED -- The driver is no longer accepting operations
104 * from your process.  That is, the process is being destroyed.
105 * You should handle this by exiting from your process.  Note
106 * that once this error code is returned, all further calls to
107 * the driver from any thread will return this same code.
108 */
109
110enum transaction_flags {
111	TF_ONE_WAY	= 0x01,	/* this is a one-way call: async, no return */
112	TF_ROOT_OBJECT	= 0x04,	/* contents are the component's root object */
113	TF_STATUS_CODE	= 0x08,	/* contents are a 32-bit status code */
114	TF_ACCEPT_FDS	= 0x10,	/* allow replies with file descriptors */
115};
116
117struct binder_transaction_data {
118	/* The first two are only used for bcTRANSACTION and brTRANSACTION,
119	 * identifying the target and contents of the transaction.
120	 */
121	union {
122		__u32	handle;	/* target descriptor of command transaction */
123		void	*ptr;	/* target descriptor of return transaction */
124	} target;
125	void		*cookie;	/* target object cookie */
126	__u32		code;		/* transaction command */
127
128	/* General information about the transaction. */
129	__u32	        flags;
130	pid_t		sender_pid;
131	uid_t		sender_euid;
132	size_t		data_size;	/* number of bytes of data */
133	size_t		offsets_size;	/* number of bytes of offsets */
134
135	/* If this transaction is inline, the data immediately
136	 * follows here; otherwise, it ends with a pointer to
137	 * the data buffer.
138	 */
139	union {
140		struct {
141			/* transaction data */
142			const void __user	*buffer;
143			/* offsets from buffer to flat_binder_object structs */
144			const void __user	*offsets;
145		} ptr;
146		__u8	buf[8];
147	} data;
148};
149
150struct binder_ptr_cookie {
151	void *ptr;
152	void *cookie;
153};
154
155struct binder_handle_cookie {
156	__u32 handle;
157	void *cookie;
158} __attribute__((packed));
159
160struct binder_pri_desc {
161	__s32 priority;
162	__u32 desc;
163};
164
165struct binder_pri_ptr_cookie {
166	__s32 priority;
167	void *ptr;
168	void *cookie;
169};
170
171enum binder_driver_return_protocol {
172	BR_ERROR = _IOR('r', 0, __s32),
173	/*
174	 * int: error code
175	 */
176
177	BR_OK = _IO('r', 1),
178	/* No parameters! */
179
180	BR_TRANSACTION = _IOR('r', 2, struct binder_transaction_data),
181	BR_REPLY = _IOR('r', 3, struct binder_transaction_data),
182	/*
183	 * binder_transaction_data: the received command.
184	 */
185
186	BR_ACQUIRE_RESULT = _IOR('r', 4, __s32),
187	/*
188	 * not currently supported
189	 * int: 0 if the last bcATTEMPT_ACQUIRE was not successful.
190	 * Else the remote object has acquired a primary reference.
191	 */
192
193	BR_DEAD_REPLY = _IO('r', 5),
194	/*
195	 * The target of the last transaction (either a bcTRANSACTION or
196	 * a bcATTEMPT_ACQUIRE) is no longer with us.  No parameters.
197	 */
198
199	BR_TRANSACTION_COMPLETE = _IO('r', 6),
200	/*
201	 * No parameters... always refers to the last transaction requested
202	 * (including replies).  Note that this will be sent even for
203	 * asynchronous transactions.
204	 */
205
206	BR_INCREFS = _IOR('r', 7, struct binder_ptr_cookie),
207	BR_ACQUIRE = _IOR('r', 8, struct binder_ptr_cookie),
208	BR_RELEASE = _IOR('r', 9, struct binder_ptr_cookie),
209	BR_DECREFS = _IOR('r', 10, struct binder_ptr_cookie),
210	/*
211	 * void *:	ptr to binder
212	 * void *: cookie for binder
213	 */
214
215	BR_ATTEMPT_ACQUIRE = _IOR('r', 11, struct binder_pri_ptr_cookie),
216	/*
217	 * not currently supported
218	 * int:	priority
219	 * void *: ptr to binder
220	 * void *: cookie for binder
221	 */
222
223	BR_NOOP = _IO('r', 12),
224	/*
225	 * No parameters.  Do nothing and examine the next command.  It exists
226	 * primarily so that we can replace it with a BR_SPAWN_LOOPER command.
227	 */
228
229	BR_SPAWN_LOOPER = _IO('r', 13),
230	/*
231	 * No parameters.  The driver has determined that a process has no
232	 * threads waiting to service incoming transactions.  When a process
233	 * receives this command, it must spawn a new service thread and
234	 * register it via bcENTER_LOOPER.
235	 */
236
237	BR_FINISHED = _IO('r', 14),
238	/*
239	 * not currently supported
240	 * stop threadpool thread
241	 */
242
243	BR_DEAD_BINDER = _IOR('r', 15, void *),
244	/*
245	 * void *: cookie
246	 */
247	BR_CLEAR_DEATH_NOTIFICATION_DONE = _IOR('r', 16, void *),
248	/*
249	 * void *: cookie
250	 */
251
252	BR_FAILED_REPLY = _IO('r', 17),
253	/*
254	 * The the last transaction (either a bcTRANSACTION or
255	 * a bcATTEMPT_ACQUIRE) failed (e.g. out of memory).  No parameters.
256	 */
257};
258
259enum binder_driver_command_protocol {
260	BC_TRANSACTION = _IOW('c', 0, struct binder_transaction_data),
261	BC_REPLY = _IOW('c', 1, struct binder_transaction_data),
262	/*
263	 * binder_transaction_data: the sent command.
264	 */
265
266	BC_ACQUIRE_RESULT = _IOW('c', 2, __s32),
267	/*
268	 * not currently supported
269	 * int:  0 if the last BR_ATTEMPT_ACQUIRE was not successful.
270	 * Else you have acquired a primary reference on the object.
271	 */
272
273	BC_FREE_BUFFER = _IOW('c', 3, void *),
274	/*
275	 * void *: ptr to transaction data received on a read
276	 */
277
278	BC_INCREFS = _IOW('c', 4, __u32),
279	BC_ACQUIRE = _IOW('c', 5, __u32),
280	BC_RELEASE = _IOW('c', 6, __u32),
281	BC_DECREFS = _IOW('c', 7, __u32),
282	/*
283	 * int:	descriptor
284	 */
285
286	BC_INCREFS_DONE = _IOW('c', 8, struct binder_ptr_cookie),
287	BC_ACQUIRE_DONE = _IOW('c', 9, struct binder_ptr_cookie),
288	/*
289	 * void *: ptr to binder
290	 * void *: cookie for binder
291	 */
292
293	BC_ATTEMPT_ACQUIRE = _IOW('c', 10, struct binder_pri_desc),
294	/*
295	 * not currently supported
296	 * int: priority
297	 * int: descriptor
298	 */
299
300	BC_REGISTER_LOOPER = _IO('c', 11),
301	/*
302	 * No parameters.
303	 * Register a spawned looper thread with the device.
304	 */
305
306	BC_ENTER_LOOPER = _IO('c', 12),
307	BC_EXIT_LOOPER = _IO('c', 13),
308	/*
309	 * No parameters.
310	 * These two commands are sent as an application-level thread
311	 * enters and exits the binder loop, respectively.  They are
312	 * used so the binder can have an accurate count of the number
313	 * of looping threads it has available.
314	 */
315
316	BC_REQUEST_DEATH_NOTIFICATION = _IOW('c', 14,
317						struct binder_handle_cookie),
318	/*
319	 * int: handle
320	 * void *: cookie
321	 */
322
323	BC_CLEAR_DEATH_NOTIFICATION = _IOW('c', 15,
324						struct binder_handle_cookie),
325	/*
326	 * int: handle
327	 * void *: cookie
328	 */
329
330	BC_DEAD_BINDER_DONE = _IOW('c', 16, void *),
331	/*
332	 * void *: cookie
333	 */
334};
335
336#endif /* _UAPI_LINUX_BINDER_H */
337
338