mount.h

基于组件方式开发操作系统的OSKIT源代码

/*	$NetBSD: mount.h,v 1.48 1996/02/18 11:55:47 fvdl 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	8.15 (Berkeley) 7/14/94
 */

#ifndef _KERNEL
#include <sys/ucred.h>
#endif
#include <sys/queue.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 (unused; zero) */
	short	f_flags;		/* 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_spare[4];		/* 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_LOFS	"lofs"		/* Loopback filesystem */
#define	MOUNT_FDESC	"fdesc"		/* File Descriptor Filesystem */
#define	MOUNT_PORTAL	"portal"	/* Portal Filesystem */
#define	MOUNT_NULL	"null"		/* Minimal 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 */

/*
 * 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 vnodelst	mnt_vnodelist;		/* list of vnodes this mount */
	int		mnt_flag;		/* flags */
	int		mnt_maxsymlinklen;	/* max size of short symlink */
	struct statfs	mnt_stat;		/* cache of filesystem stats */
	qaddr_t		mnt_data;		/* private data */
};

/*
 * Mount flags.
 *
 * Unmount uses MNT_FORCE flag.
 */
#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 */

/*
 * 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 */

/*
 * 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	0x0000ffff

/*
 * 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 */
#define	MNT_MLOCK	0x00100000	/* lock so that subtree is stable */
#define	MNT_MWAIT	0x00200000	/* someone is waiting for lock */
#define MNT_MPBUSY	0x00400000	/* scan of mount point in progress */
#define MNT_MPWANT	0x00800000	/* waiting for mount point */
#define MNT_UNMOUNT	0x01000000	/* unmount in progress */
#define MNT_WANTRDWR	0x02000000	/* want upgrade to read/write */

/*
 * Operations supported on mounted file system.
 */
#ifdef _KERNEL
#ifdef __STDC__
struct nameidata;
struct mbuf;
#endif

struct vfsops {
	char	*vfs_name;
	int	(*vfs_mount)	__P((struct mount *mp, char *path, caddr_t data,
				    struct nameidata *ndp, struct proc *p));
	int	(*vfs_start)	__P((struct mount *mp, int flags,
				    struct proc *p));
	int	(*vfs_unmount)	__P((struct mount *mp, int mntflags,
				    struct proc *p));
	int	(*vfs_root)	__P((struct mount *mp, struct vnode **vpp));
	int	(*vfs_quotactl)	__P((struct mount *mp, int cmds, uid_t uid,
				    caddr_t arg, struct proc *p));
	int	(*vfs_statfs)	__P((struct mount *mp, struct statfs *sbp,
				    struct proc *p));
	int	(*vfs_sync)	__P((struct mount *mp, int waitfor,
				    struct ucred *cred, struct proc *p));
	int	(*vfs_vget)	__P((struct mount *mp, ino_t ino,
				    struct vnode **vpp));
	int	(*vfs_fhtovp)	__P((struct mount *mp, struct fid *fhp,
				    struct mbuf *nam, struct vnode **vpp,
				    int *exflagsp, struct ucred **credanonp));
	int	(*vfs_vptofh)	__P((struct vnode *vp, struct fid *fhp));
	void	(*vfs_init)	__P((void));
	int	vfs_refcount;
};

#define VFS_MOUNT(MP, PATH, DATA, NDP, P) \
	(*(MP)->mnt_op->vfs_mount)(MP, PATH, DATA, NDP, P)
#define VFS_START(MP, FLAGS, P)	  (*(MP)->mnt_op->vfs_start)(MP, FLAGS, P)
#define VFS_UNMOUNT(MP, FORCE, P) (*(MP)->mnt_op->vfs_unmount)(MP, FORCE, P)
#define VFS_ROOT(MP, VPP)	  (*(MP)->mnt_op->vfs_root)(MP, VPP)
#define VFS_QUOTACTL(MP,C,U,A,P)  (*(MP)->mnt_op->vfs_quotactl)(MP, C, U, A, P)
#define VFS_STATFS(MP, SBP, P)	  (*(MP)->mnt_op->vfs_statfs)(MP, SBP, P)
#define VFS_SYNC(MP, WAIT, C, P)  (*(MP)->mnt_op->vfs_sync)(MP, WAIT, C, P)
#define VFS_VGET(MP, INO, VPP)	  (*(MP)->mnt_op->vfs_vget)(MP, INO, VPP)
#define VFS_FHTOVP(MP, FIDP, NAM, VPP, EXFLG, CRED) \
	(*(MP)->mnt_op->vfs_fhtovp)(MP, FIDP, NAM, VPP, EXFLG, CRED)
#define	VFS_VPTOFH(VP, FIDP)	  (*(VP)->v_mount->mnt_op->vfs_vptofh)(VP, FIDP)