17c478bd9Sstevel@tonic-gate /* 27c478bd9Sstevel@tonic-gate * CDDL HEADER START 37c478bd9Sstevel@tonic-gate * 47c478bd9Sstevel@tonic-gate * The contents of this file are subject to the terms of the 57c478bd9Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only 67c478bd9Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance 77c478bd9Sstevel@tonic-gate * with the License. 87c478bd9Sstevel@tonic-gate * 97c478bd9Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 107c478bd9Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 117c478bd9Sstevel@tonic-gate * See the License for the specific language governing permissions 127c478bd9Sstevel@tonic-gate * and limitations under the License. 137c478bd9Sstevel@tonic-gate * 147c478bd9Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 157c478bd9Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 167c478bd9Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 177c478bd9Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 187c478bd9Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 197c478bd9Sstevel@tonic-gate * 207c478bd9Sstevel@tonic-gate * CDDL HEADER END 217c478bd9Sstevel@tonic-gate */ 227c478bd9Sstevel@tonic-gate /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 23*b4203d75SMarcel Telka /* All Rights Reserved */ 247c478bd9Sstevel@tonic-gate 257c478bd9Sstevel@tonic-gate 267c478bd9Sstevel@tonic-gate #ifndef _SYS_OPEN_H 277c478bd9Sstevel@tonic-gate #define _SYS_OPEN_H 287c478bd9Sstevel@tonic-gate 297c478bd9Sstevel@tonic-gate #ifdef __cplusplus 307c478bd9Sstevel@tonic-gate extern "C" { 317c478bd9Sstevel@tonic-gate #endif 327c478bd9Sstevel@tonic-gate 337c478bd9Sstevel@tonic-gate /* 347c478bd9Sstevel@tonic-gate * Some drivers need to be able to keep accurate records of open/close 357c478bd9Sstevel@tonic-gate * calls to determine whether a device is still in use. To allow this 367c478bd9Sstevel@tonic-gate * open/close calls have been typed and the type is passed as a third 377c478bd9Sstevel@tonic-gate * argument in open/close calls, as in: 387c478bd9Sstevel@tonic-gate * (*cdevsw[getmajor(dev)].d_open)(getminor(dev), flag, OTYP_CHR); 397c478bd9Sstevel@tonic-gate * or 407c478bd9Sstevel@tonic-gate * (*cdevsw[getmajor(dev)].d_close)(getminor(dev), flag, OTYP_CHR); 417c478bd9Sstevel@tonic-gate * Five types of open/close calls have been defined: 427c478bd9Sstevel@tonic-gate * OTYP_BLK: open/close of a block special file 437c478bd9Sstevel@tonic-gate * OTYP_MNT: open/close for mounting/unmounting a file system 447c478bd9Sstevel@tonic-gate * OTYP_CHR: open/close of a character special file 457c478bd9Sstevel@tonic-gate * OTYP_SWP: open/close of a swapping device. 467c478bd9Sstevel@tonic-gate * OTYP_LYR: open/close calls from a driver to another driver, 477c478bd9Sstevel@tonic-gate * without a file being open for the dev of the lower driver. 487c478bd9Sstevel@tonic-gate * 497c478bd9Sstevel@tonic-gate * The first four types of open/close calls obey the protocol rule 507c478bd9Sstevel@tonic-gate * that many more opens may occur for a given minor(dev) for that type of open, 517c478bd9Sstevel@tonic-gate * but a close call happens only on the last close of that dev. 527c478bd9Sstevel@tonic-gate * This protocol allows a flag to be used (set by opens, cleared by closes) 537c478bd9Sstevel@tonic-gate * to keep track of the state for a given minor device value. 547c478bd9Sstevel@tonic-gate * 557c478bd9Sstevel@tonic-gate * Calls of the fifth type (OTYP_LYR) must obey the protocol rule 567c478bd9Sstevel@tonic-gate * that open and close call calls are always paired. This protocol 577c478bd9Sstevel@tonic-gate * permits several drivers to be layers above the same device driver. 587c478bd9Sstevel@tonic-gate * A counter can be used for this protocol. 597c478bd9Sstevel@tonic-gate * 607c478bd9Sstevel@tonic-gate * The value OTYPCNT is defined for the purpose of declaring arrays 617c478bd9Sstevel@tonic-gate * in drivers and for performing range checks (0 <= otyp < OTYPCNT) 627c478bd9Sstevel@tonic-gate * on values passed. 637c478bd9Sstevel@tonic-gate */ 647c478bd9Sstevel@tonic-gate 657c478bd9Sstevel@tonic-gate #define OTYPCNT 5 667c478bd9Sstevel@tonic-gate #define OTYP_BLK 0 677c478bd9Sstevel@tonic-gate #define OTYP_MNT 1 687c478bd9Sstevel@tonic-gate #define OTYP_CHR 2 697c478bd9Sstevel@tonic-gate #define OTYP_SWP 3 707c478bd9Sstevel@tonic-gate #define OTYP_LYR 4 717c478bd9Sstevel@tonic-gate 727c478bd9Sstevel@tonic-gate #ifdef __cplusplus 737c478bd9Sstevel@tonic-gate } 747c478bd9Sstevel@tonic-gate #endif 757c478bd9Sstevel@tonic-gate 767c478bd9Sstevel@tonic-gate #endif /* _SYS_OPEN_H */ 77