mount.h

基于组件方式开发操作系统的OSKIT源代码

/*	$NetBSD: mount.h,v 1.87 2000/11/27 08:39:52 chs Exp $	*/

/*
 * Copyright (c) 1989, 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)mount.h	8.21 (Berkeley) 5/20/95
 */

#ifndef _SYS_MOUNT_H_
#define _SYS_MOUNT_H_

#ifndef _KERNEL
#include <sys/ucred.h>
#if !defined(_POSIX_C_SOURCE) && !defined(_XOPEN_SOURCE)
#include <sys/stat.h>
#endif /* !_POSIX_C_SOURCE */
#endif
#include <sys/queue.h>
#include <sys/lock.h>

typedef struct { int32_t val[2]; } fsid_t;	/* file system id type */

/*
 * File identifier.
 * These are unique per filesystem on a single machine.
 */
#define	MAXFIDSZ	16

struct fid {
	u_short		fid_len;		/* length of data in bytes */
	u_short		fid_reserved;		/* force longword alignment */
	char		fid_data[MAXFIDSZ];	/* data (variable length) */
};

/*
 * file system statistics
 */

#define	MFSNAMELEN	16	/* length of fs type name, including nul */
#define	MNAMELEN	90	/* length of buffer for returned name */

struct statfs {
	short	f_type;			/* type of file system */
	u_short	f_oflags;		/* deprecated copy of mount flags */
	long	f_bsize;		/* fundamental file system block size */
	long	f_iosize;		/* optimal transfer block size */
	long	f_blocks;		/* total data blocks in file system */
	long	f_bfree;		/* free blocks in fs */
	long	f_bavail;		/* free blocks avail to non-superuser */
	long	f_files;		/* total file nodes in file system */
	long	f_ffree;		/* free file nodes in fs */
	fsid_t	f_fsid;			/* file system id */
	uid_t	f_owner;		/* user that mounted the file system */
	long	f_flags;		/* copy of mount flags */
	long	f_syncwrites;		/* count of sync writes since mount */
	long	f_asyncwrites;		/* count of async writes since mount */
	long	f_spare[1];		/* spare for later */
	char	f_fstypename[MFSNAMELEN]; /* fs type name */
	char	f_mntonname[MNAMELEN];	  /* directory on which mounted */
	char	f_mntfromname[MNAMELEN];  /* mounted file system */
};

/*
 * File system types.
 */
#define	MOUNT_FFS	"ffs"		/* UNIX "Fast" Filesystem */
#define	MOUNT_UFS	MOUNT_FFS	/* for compatibility */
#define	MOUNT_NFS	"nfs"		/* Network Filesystem */
#define	MOUNT_MFS	"mfs"		/* Memory Filesystem */
#define	MOUNT_MSDOS	"msdos"		/* MSDOS Filesystem */
#define	MOUNT_LFS	"lfs"		/* Log-based Filesystem */
#define	MOUNT_FDESC	"fdesc"		/* File Descriptor Filesystem */
#define	MOUNT_PORTAL	"portal"	/* Portal Filesystem */
#define	MOUNT_NULL	"null"		/* Minimal Filesystem Layer */
#define	MOUNT_OVERLAY	"overlay"	/* Minimal Overlay Filesystem Layer */
#define	MOUNT_UMAP	"umap"	/* User/Group Identifier Remapping Filesystem */
#define	MOUNT_KERNFS	"kernfs"	/* Kernel Information Filesystem */
#define	MOUNT_PROCFS	"procfs"	/* /proc Filesystem */
#define	MOUNT_AFS	"afs"		/* Andrew Filesystem */
#define	MOUNT_CD9660	"cd9660"	/* ISO9660 (aka CDROM) Filesystem */
#define	MOUNT_UNION	"union"		/* Union (translucent) Filesystem */
#define	MOUNT_ADOSFS	"adosfs"	/* AmigaDOS Filesystem */
#define	MOUNT_EXT2FS	"ext2fs"	/* Second Extended Filesystem */
#define	MOUNT_CFS	"coda"		/* Coda Filesystem */
#define	MOUNT_CODA	"coda"		/* Coda Filesystem */
#define	MOUNT_FILECORE	"filecore"	/* Acorn Filecore Filesystem */
#define	MOUNT_NTFS	"ntfs"		/* Windows/NT Filesystem */

/*
 * Structure per mounted file system.  Each mounted file system has an
 * array of operations and an instance record.  The file systems are
 * put on a doubly linked list.
 */
LIST_HEAD(vnodelst, vnode);

struct mount {
	CIRCLEQ_ENTRY(mount) mnt_list;		/* mount list */
	struct vfsops	*mnt_op;		/* operations on fs */
	struct vnode	*mnt_vnodecovered;	/* vnode we mounted on */
	struct vnode	*mnt_syncer;		/* syncer vnode */
	struct vnodelst	mnt_vnodelist;		/* list of vnodes this mount */
	struct lock	mnt_lock;		/* mount structure lock */
	int		mnt_flag;		/* flags */
	int		mnt_maxsymlinklen;	/* max size of short symlink */
	int		mnt_fs_bshift;		/* offset shift for lblkno */
	int		mnt_dev_bshift;		/* shift for device sectors */
	struct statfs	mnt_stat;		/* cache of filesystem stats */
	qaddr_t		mnt_data;		/* private data */
	int		mnt_wcnt;		/* count of vfs_busy waiters */
	struct proc	*mnt_unmounter;		/* who is unmounting */
};

/*
 * Mount flags.  XXX BEWARE: these are not in numerical order!
 *
 * Unmount uses MNT_FORCE flag.
 *
 * Note that all mount flags are listed here.  if you need to add one, take
 * one of the __MNT_UNUSED flags.
 */

#define __MNT_UNUSED2	0x00400000
#define __MNT_UNUSED3	0x00800000

#define	MNT_RDONLY	0x00000001	/* read only filesystem */
#define	MNT_SYNCHRONOUS	0x00000002	/* file system written synchronously */
#define	MNT_NOEXEC	0x00000004	/* can't exec from filesystem */
#define	MNT_NOSUID	0x00000008	/* don't honor setuid bits on fs */
#define	MNT_NODEV	0x00000010	/* don't interpret special files */
#define	MNT_UNION	0x00000020	/* union with underlying filesystem */
#define	MNT_ASYNC	0x00000040	/* file system written asynchronously */
#define	MNT_NOCOREDUMP	0x00008000	/* don't write core dumps to this FS */
#define MNT_IGNORE	0x00100000	/* don't show entry in df */
#define MNT_NOATIME	0x04000000	/* Never update access times in fs */
#define MNT_SYMPERM	0x20000000	/* recognize symlink permission */
#define MNT_NODEVMTIME	0x40000000	/* Never update mod times for devs */
#define MNT_SOFTDEP	0x80000000	/* Use soft dependencies */

/*
 * exported mount flags.
 */
#define	MNT_EXRDONLY	0x00000080	/* exported read only */
#define	MNT_EXPORTED	0x00000100	/* file system is exported */
#define	MNT_DEFEXPORTED	0x00000200	/* exported to the world */
#define	MNT_EXPORTANON	0x00000400	/* use anon uid mapping for everyone */
#define	MNT_EXKERB	0x00000800	/* exported with Kerberos uid mapping */
#define MNT_EXNORESPORT	0x08000000	/* don't enforce reserved ports (NFS) */
#define MNT_EXPUBLIC	0x10000000	/* public export (WebNFS) */

/*
 * Flags set by internal operations.
 */
#define	MNT_LOCAL	0x00001000	/* filesystem is stored locally */
#define	MNT_QUOTA	0x00002000	/* quotas are enabled on filesystem */
#define	MNT_ROOTFS	0x00004000	/* identifies the root filesystem */

/*
 * Mask of flags that are visible to statfs()
 */
#define	MNT_VISFLAGMASK	0xfc10ffff

/*
 * External filesystem control flags.
 *
 * MNT_MLOCK lock the mount entry so that name lookup cannot proceed
 * past the mount point.  This keeps the subtree stable during mounts
 * and unmounts.
 */
#define	MNT_UPDATE	0x00010000	/* not a real mount, just an update */
#define	MNT_DELEXPORT	0x00020000	/* delete export host lists */
#define	MNT_RELOAD	0x00040000	/* reload filesystem data */
#define	MNT_FORCE	0x00080000	/* force unmount or readonly change */

/*
 * Internal filesystem control flags.
 *
 * MNT_UNMOUNT locks the mount entry so that name lookup cannot proceed
 * past the mount point.  This keeps the subtree stable during mounts
 * and unmounts.
 */
#define	MNT_GONE	0x00200000	/* filesystem is gone.. */
#define MNT_UNMOUNT	0x01000000	/* unmount in progress */
#define MNT_WANTRDWR	0x02000000	/* upgrade to read/write requested */

/*
 * Sysctl CTL_VFS definitions.
 *
 * Second level identifier specifies which filesystem. Second level
 * identifier VFS_GENERIC returns information about all filesystems.
 *
 * Note the slightly non-flat nature of these sysctl numbers.  Oh for
 * a better sysctl interface.
 */
#define VFS_GENERIC	0		/* generic filesystem information */
#define VFS_MAXTYPENUM	1		/* int: highest defined fs type */
#define VFS_CONF	2		/* struct: vfsconf for filesystem given
					   as next argument */
#define VFS_USERMOUNT	3		/* enable/disable fs mnt by non-root */
#define	VFSGEN_MAXID	4		/* number of valid vfs.generic ids */

/*
 * XXX NOTE!  These must be in the order of mountcompatnames[] in
 * XXX sys/kern/vfs_syscalls.c!
 *
 * USE THE SAME NAMES AS MOUNT_*!
 */
#define	CTL_VFS_NAMES { \
	{ "generic", CTLTYPE_NODE }, \
	{ MOUNT_FFS, CTLTYPE_NODE }, \
	{ MOUNT_NFS, CTLTYPE_NODE }, \