1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21/*
22 * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
23 */
24/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
25/*	  All Rights Reserved  	*/
26
27
28#ifndef _SYS_PTMS_H
29#define	_SYS_PTMS_H
30
31#ifdef	__cplusplus
32extern "C" {
33#endif
34
35#ifdef _KERNEL
36
37/*
38 * Structures and definitions supporting the pseudo terminal
39 * drivers. This structure is private and should not be used by any
40 * applications.
41 */
42struct pt_ttys {
43	queue_t *ptm_rdq; 	/* master's read queue pointer */
44	queue_t *pts_rdq; 	/* slave's read queue pointer */
45	mblk_t	*pt_nullmsg;	/* 0-bytes message block for pts close */
46	pid_t	 pt_pid;	/* process id (for debugging) */
47	minor_t	 pt_minor;	/* Minor number of this pty */
48	int	 pt_refcnt;	/* reference count for ptm_rdq/pts_rdq uses */
49	ushort_t pt_state;	/* state of master/slave pair */
50	kcondvar_t pt_cv;	/* condition variable for exclusive access */
51	kmutex_t pt_lock;	/* Per-element lock */
52	zoneid_t pt_zoneid;	/* Zone membership for this pty */
53	uid_t	 pt_ruid;	/* Real owner of pty */
54	gid_t	 pt_rgid;	/* Real group owner of pty */
55};
56
57/*
58 * pt_state values
59 */
60#define	PTLOCK		0x01	/* master/slave pair is locked */
61#define	PTMOPEN 	0x02  	/* master side is open */
62#define	PTSOPEN 	0x04	/* slave side is open */
63#define	PTSTTY		0x08	/* slave side is tty */
64
65/*
66 * Multi-threading primitives.
67 * Values of pt_refcnt: -1 if a writer is accessing the struct
68 *			0  if no one is reading or writing
69 *			> 0 equals to the number of readers accessing the struct
70 */
71#define	PT_ENTER_READ(p) {			\
72	mutex_enter(&(p)->pt_lock);		\
73	while ((p)->pt_refcnt < 0)		\
74		cv_wait(&((p)->pt_cv), &(p)->pt_lock);	\
75	(p)->pt_refcnt++;			\
76	mutex_exit(&(p)->pt_lock);		\
77}
78
79#define	PT_ENTER_WRITE(p) {			\
80	mutex_enter(&(p)->pt_lock);		\
81	while ((p)->pt_refcnt != 0)		\
82		cv_wait(&((p)->pt_cv), &(p)->pt_lock);	\
83	(p)->pt_refcnt = -1;			\
84	mutex_exit(&(p)->pt_lock);		\
85}
86
87#define	PT_EXIT_READ(p) {			\
88	mutex_enter(&(p)->pt_lock);		\
89	ASSERT((p)->pt_refcnt > 0);		\
90	if ((--((p)->pt_refcnt)) == 0)		\
91		cv_broadcast(&(p)->pt_cv);	\
92	mutex_exit(&(p)->pt_lock);		\
93}
94
95#define	PT_EXIT_WRITE(p) {			\
96	mutex_enter(&(p)->pt_lock);		\
97	ASSERT((p)->pt_refcnt == -1);		\
98	(p)->pt_refcnt = 0;			\
99	cv_broadcast(&(p)->pt_cv);		\
100	mutex_exit(&(p)->pt_lock);		\
101}
102
103/*
104 * ptms_lock and pt_cnt are defined in ptms_conf.c
105 */
106extern kmutex_t		ptms_lock;
107extern dev_info_t 	*pts_dip;	/* private copy of devinfo ptr */
108
109extern void ptms_init(void);
110extern struct pt_ttys *pt_ttys_alloc(void);
111extern void ptms_close(struct pt_ttys *, uint_t);
112extern struct pt_ttys *ptms_minor2ptty(minor_t);
113extern int ptms_attach_slave(void);
114extern int ptms_minor_valid(minor_t ptmin, uid_t *uid, gid_t *gid);
115extern int ptms_minor_exists(minor_t ptmin);
116extern void ptms_set_owner(minor_t ptmin, uid_t uid, gid_t gid);
117extern major_t ptms_slave_attached(void);
118
119#ifdef DEBUG
120extern void ptms_log(char *, uint_t);
121extern void ptms_logp(char *, uintptr_t);
122#define	DDBG(a, b) ptms_log(a, b)
123#define	DDBGP(a, b) ptms_logp(a, b)
124#else
125#define	DDBG(a, b)
126#define	DDBGP(a, b)
127#endif
128
129#endif /* _KERNEL */
130
131typedef struct pt_own {
132	uid_t	pto_ruid;
133	gid_t	pto_rgid;
134} pt_own_t;
135
136/*
137 * ioctl commands
138 *
139 *  ISPTM: Determines whether the file descriptor is that of an open master
140 *	   device. Return code of zero indicates that the file descriptor
141 *	   represents master device.
142 *
143 * UNLKPT: Unlocks the master and slave devices.  It returns 0 on success. On
144 *	   failure, the errno is set to EINVAL indicating that the master
145 *	   device is not open.
146 *
147 *  ZONEPT: Sets the zoneid of the pair of master and slave devices.  It
148 *	    returns 0 upon success.  Used to force a pty 'into' a zone upon
149 *	    zone entry.
150 *
151 * PT_OWNER: Sets uid and gid for slave device.  It returns 0 on success.
152 *
153 */
154#define	ISPTM		(('P'<<8)|1)	/* query for master */
155#define	UNLKPT		(('P'<<8)|2)	/* unlock master/slave pair */
156#define	PTSSTTY		(('P'<<8)|3)	/* set tty flag */
157#define	ZONEPT		(('P'<<8)|4)	/* set zone of master/slave pair */
158#define	OWNERPT		(('P'<<8)|5)	/* set owner/group for slave device */
159
160#ifdef	__cplusplus
161}
162#endif
163
164#endif	/* _SYS_PTMS_H */
165