inode.h

来自「早期freebsd实现」· C头文件 代码 · 共 163 行

/*
 * Copyright (c) 1982, 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * 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.
 *
 *	@(#)inode.h	8.4 (Berkeley) 1/21/94
 */

#include <ufs/ufs/dinode.h>

/*
 * Theoretically, directories can be more than 2Gb in length, however, in
 * practice this seems unlikely. So, we define the type doff_t as a long
 * to keep down the cost of doing lookup on a 32-bit machine. If you are
 * porting to a 64-bit architecture, you should make doff_t the same as off_t.
 */
#define	doff_t	long

/*
 * The inode is used to describe each active (or recently active)
 * file in the UFS filesystem. It is composed of two types of
 * information. The first part is the information that is needed
 * only while the file is active (such as the identity of the file
 * and linkage to speed its lookup). The second part is the 
 * permannent meta-data associated with the file which is read
 * in from the permanent dinode from long term storage when the
 * file becomes active, and is put back when the file is no longer
 * being used.
 */
struct inode {
	struct	inode *i_next;	/* Hash chain forward. */
	struct	inode **i_prev;	/* Hash chain back. */
	struct	vnode *i_vnode;	/* Vnode associated with this inode. */
	struct	vnode *i_devvp;	/* Vnode for block I/O. */
	u_long	i_flag;		/* I* flags. */
	dev_t	i_dev;		/* Device associated with the inode. */
	ino_t	i_number;	/* The identity of the inode. */
	union {			/* Associated filesystem. */
		struct	fs *fs;		/* FFS */
		struct	lfs *lfs;	/* LFS */
	} inode_u;
#define	i_fs	inode_u.fs
#define	i_lfs	inode_u.lfs
	struct	dquot *i_dquot[MAXQUOTAS];	/* Dquot structures. */
	u_quad_t i_modrev;	/* Revision level for lease. */
	struct	lockf *i_lockf;	/* Head of byte-level lock list. */
	pid_t	i_lockholder;	/* DEBUG: holder of inode lock. */
	pid_t	i_lockwaiter;	/* DEBUG: latest blocked for inode lock. */
	/*
	 * Side effects; used during directory lookup.
	 */
	long	i_count;	/* Size of free slot in directory. */
	doff_t	i_endoff;	/* End of useful stuff in directory. */
	doff_t	i_diroff;	/* Offset in dir, where we found last entry. */
	doff_t	i_offset;	/* Offset of free space in directory. */
	ino_t	i_ino;		/* Inode number of found directory. */
	u_long	i_reclen;	/* Size of found directory entry. */
	long	i_spare[11];	/* Spares to round up to 128 bytes. */
	/*
	 * The on-disk dinode itself.
	 */
	struct	dinode i_din;	/* 128 bytes of the on-disk dinode. */
};

#define	i_atime		i_din.di_atime
#define	i_blocks	i_din.di_blocks
#define	i_ctime		i_din.di_ctime
#define	i_db		i_din.di_db
#define	i_flags		i_din.di_flags
#define	i_gen		i_din.di_gen
#define	i_gid		i_din.di_gid
#define	i_ib		i_din.di_ib
#define	i_mode		i_din.di_mode
#define	i_mtime		i_din.di_mtime
#define	i_nlink		i_din.di_nlink
#define	i_rdev		i_din.di_rdev
#define	i_shortlink	i_din.di_shortlink
#define	i_size		i_din.di_size
#define	i_uid		i_din.di_uid

/* These flags are kept in i_flag. */
#define	IN_ACCESS	0x0001		/* Access time update request. */
#define	IN_CHANGE	0x0002		/* Inode change time update request. */
#define	IN_EXLOCK	0x0004		/* File has exclusive lock. */
#define	IN_LOCKED	0x0008		/* Inode lock. */
#define	IN_LWAIT	0x0010		/* Process waiting on file lock. */
#define	IN_MODIFIED	0x0020		/* Inode has been modified. */
#define	IN_RENAME	0x0040		/* Inode is being renamed. */
#define	IN_SHLOCK	0x0080		/* File has shared lock. */
#define	IN_UPDATE	0x0100		/* Modification time update request. */
#define	IN_WANTED	0x0200		/* Inode is wanted by a process. */

#ifdef KERNEL
/*
 * Structure used to pass around logical block paths generated by
 * ufs_getlbns and used by truncate and bmap code.
 */
struct indir {
	daddr_t	in_lbn;			/* Logical block number. */
	int	in_off;			/* Offset in buffer. */
	int	in_exists;		/* Flag if the block exists. */
};

/* Convert between inode pointers and vnode pointers. */
#define VTOI(vp)	((struct inode *)(vp)->v_data)
#define ITOV(ip)	((ip)->i_vnode)

#define	ITIMES(ip, t1, t2) {						\
	if ((ip)->i_flag & (IN_ACCESS | IN_CHANGE | IN_UPDATE)) {	\
		(ip)->i_flag |= IN_MODIFIED;				\
		if ((ip)->i_flag & IN_ACCESS)				\
			(ip)->i_atime.ts_sec = (t1)->tv_sec;		\
		if ((ip)->i_flag & IN_UPDATE) {				\
			(ip)->i_mtime.ts_sec = (t2)->tv_sec;		\
			(ip)->i_modrev++;				\
		}							\
		if ((ip)->i_flag & IN_CHANGE)				\
			(ip)->i_ctime.ts_sec = time.tv_sec;		\
		(ip)->i_flag &= ~(IN_ACCESS | IN_CHANGE | IN_UPDATE);	\
	}								\
}

/* This overlays the fid structure (see mount.h). */
struct ufid {
	u_short	ufid_len;	/* Length of structure. */
	u_short	ufid_pad;	/* Force long alignment. */
	ino_t	ufid_ino;	/* File number (ino). */
	long	ufid_gen;	/* Generation number. */
};
#endif /* KERNEL */