usr/src/uts/common/sys/ptms.h

   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
  32 extern "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  */
  42 struct 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  */
 106 extern kmutex_t         ptms_lock;
 107 extern dev_info_t       *pts_dip;       /* private copy of devinfo ptr */
 108
 109 extern void ptms_init(void);
 110 extern struct pt_ttys *pt_ttys_alloc(void);
 111 extern void ptms_close(struct pt_ttys *, uint_t);
 112 extern struct pt_ttys *ptms_minor2ptty(minor_t);
 113 extern int ptms_attach_slave(void);
 114 extern int ptms_minor_valid(minor_t ptmin, uid_t *uid, gid_t *gid);
 115 extern int ptms_minor_exists(minor_t ptmin);
 116 extern void ptms_set_owner(minor_t ptmin, uid_t uid, gid_t gid);
 117 extern major_t ptms_slave_attached(void);
 118
 119 #ifdef DEBUG
 120 extern void ptms_log(char *, uint_t);
 121 extern 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
 131 typedef 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 */