mount.h

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/*
 * 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
 *	$Id: mount.h,v 1.73 1998/11/15 15:12:58 bde Exp $
 */

#ifndef _SYS_MOUNT_H_
#define _SYS_MOUNT_H_

#include <sys/ucred.h>
#include <sys/queue.h>
#include <sys/lock.h>

typedef struct fsid { 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 null */
#define	MNAMELEN	90	/* length of buffer for returned name */

struct statfs {
	long	f_spare2;		/* placeholder */
	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 filesystem */
	int	f_type;			/* type of filesystem */
	int	f_flags;		/* copy of mount exported flags */
	long    f_syncwrites;		/* count of sync writes since mount */
	long    f_asyncwrites;		/* count of async writes since mount */
	char	f_fstypename[MFSNAMELEN]; /* fs type name */
	char	f_mntonname[MNAMELEN];	/* directory on which mounted */
	char	f_mntfromname[MNAMELEN];/* mounted 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 vfsconf	*mnt_vfc;		/* configuration info */
	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 shared with user */
	int		mnt_kern_flag;		/* kernel only flags */
	int		mnt_maxsymlinklen;	/* max size of short symlink */
	struct statfs	mnt_stat;		/* cache of filesystem stats */
	qaddr_t		mnt_data;		/* private data */
	time_t		mnt_time;		/* last time written*/
};

/*
 * User specifiable flags.
 */
#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_SUIDDIR	0x00100000	/* special handling of SUID on dirs */
#define	MNT_SOFTDEP	0x00200000	/* soft updates being done */
#define	MNT_NOSYMFOLLOW	0x00400000	/* do not follow symlinks */
#define	MNT_NOATIME	0x10000000	/* disable update of file access time */
#define	MNT_NOCLUSTERR	0x40000000	/* disable cluster read */
#define	MNT_NOCLUSTERW	0x80000000	/* disable cluster write */

/*
 * NFS export related 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_EXPUBLIC	0x20000000	/* public export (WebNFS) */

/*
 * Flags set by internal operations,
 * but visible to the user.
 * XXX some of these are not quite right.. (I've never seen the root flag set)
 */
#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 */
#define	MNT_USER	0x00008000	/* mounted by a user */

/*
 * Mask of flags that are visible to statfs()
 * XXX I think that this could now become (~(MNT_CMDFLAGS))
 * but the 'mount' program may need changing to handle this.
 * XXX MNT_EXPUBLIC is presently left out. I don't know why.
 */
#define	MNT_VISFLAGMASK	(MNT_RDONLY	| MNT_SYNCHRONOUS | MNT_NOEXEC	| \
			MNT_NOSUID	| MNT_NODEV	| MNT_UNION	| \
			MNT_ASYNC	| MNT_EXRDONLY	| MNT_EXPORTED	| \
			MNT_DEFEXPORTED	| MNT_EXPORTANON| MNT_EXKERB	| \
			MNT_LOCAL	| MNT_USER	| MNT_QUOTA	| \
			MNT_ROOTFS	| MNT_NOATIME	| MNT_NOCLUSTERR| \
			MNT_NOCLUSTERW	| MNT_SUIDDIR	| MNT_SOFTDEP	 \
			/*	| MNT_EXPUBLIC */)
/*
 * External filesystem command modifier flags.
 * Unmount can use the MNT_FORCE flag.
 * XXX These are not STATES and really should be somewhere else.
 */
#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 */
#define MNT_CMDFLAGS	(MNT_UPDATE|MNT_DELEXPORT|MNT_RELOAD|MNT_FORCE)
/*
 * Internal filesystem control flags stored in mnt_kern_flag.
 *
 * MNTK_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 MNTK_UNMOUNT	0x01000000	/* unmount in progress */
#define	MNTK_MWAIT	0x02000000	/* waiting for unmount to finish */
#define MNTK_WANTRDWR	0x04000000	/* upgrade to read/write requested */

/*
 * Sysctl CTL_VFS definitions.
 *
 * Second level identifier specifies which filesystem. Second level
 * identifier VFS_VFSCONF returns information about all filesystems.
 * Second level identifier VFS_GENERIC is non-terminal.
 */
#define	VFS_VFSCONF		0	/* get configured filesystems */
#define	VFS_GENERIC		0	/* generic filesystem information */
/*
 * Third level identifiers for VFS_GENERIC are given below; third
 * level identifiers for specific filesystems are given in their
 * mount specific header files.
 */
#define VFS_MAXTYPENUM	1	/* int: highest defined filesystem type */
#define VFS_CONF	2	/* struct: vfsconf for filesystem given
				   as next argument */

/*
 * Flags for various system call interfaces.
 *
 * waitfor flags to vfs_sync() and getfsstat()
 */
#define MNT_WAIT	1	/* synchronously wait for I/O to complete */
#define MNT_NOWAIT	2	/* start all I/O, but do not wait for it */
#define MNT_LAZY	3	/* push data not written by filesystem syncer */

/*
 * Generic file handle
 */
struct fhandle {
	fsid_t	fh_fsid;	/* File system id of mount point */
	struct	fid fh_fid;	/* File sys specific id */
};
typedef struct fhandle	fhandle_t;

/*
 * Export arguments for local filesystem mount calls.
 */
struct export_args {
	int	ex_flags;		/* export related flags */
	uid_t	ex_root;		/* mapping for root uid */
	struct	ucred ex_anon;		/* mapping for anonymous user */
	struct	sockaddr *ex_addr;	/* net address to which exported */
	int	ex_addrlen;		/* and the net address length */
	struct	sockaddr *ex_mask;	/* mask of valid bits in saddr */
	int	ex_masklen;		/* and the smask length */
	char	*ex_indexfile;		/* index file for WebNFS URLs */