xref: /original-bsd/sys/sys/vnode.h (revision b7cc7b86)
1 /*
2  * Copyright (c) 1989 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  *
7  *	@(#)vnode.h	7.32 (Berkeley) 02/01/91
8  */
9 
10 #include <machine/endian.h>
11 
12 /*
13  * The vnode is the focus of all file activity in UNIX.
14  * There is a unique vnode allocated for each active file,
15  * each current directory, each mounted-on file, text file, and the root.
16  */
17 
18 /*
19  * vnode types. VNON means no type.
20  */
21 enum vtype 	{ VNON, VREG, VDIR, VBLK, VCHR, VLNK, VSOCK, VFIFO, VBAD };
22 
23 /*
24  * Vnode tag types.
25  * These are for the benefit of external programs only (e.g., pstat)
26  * and should NEVER be inspected inside the kernel.
27  */
28 enum vtagtype	{ VT_NON, VT_UFS, VT_NFS, VT_MFS };
29 
30 /*
31  * This defines the maximum size of the private data area
32  * permitted for any file system type. A defined constant
33  * is used rather than a union structure to cut down on the
34  * number of header files that must be included.
35  */
36 #define VN_MAXPRIVATE	188
37 
38 struct vnode {
39 	u_long		v_flag;			/* vnode flags (see below) */
40 	long		v_usecount;		/* reference count of users */
41 	long		v_holdcnt;		/* page & buffer references */
42 	off_t		v_lastr;		/* last read (read-ahead) */
43 	u_long		v_id;			/* capability identifier */
44 	struct mount	*v_mount;		/* ptr to vfs we are in */
45 	struct vnodeops	*v_op;			/* vnode operations */
46 	struct vnode	*v_freef;		/* vnode freelist forward */
47 	struct vnode	**v_freeb;		/* vnode freelist back */
48 	struct vnode	*v_mountf;		/* vnode mountlist forward */
49 	struct vnode	**v_mountb;		/* vnode mountlist back */
50 	struct buf	*v_cleanblkhd;		/* clean blocklist head */
51 	struct buf	*v_dirtyblkhd;		/* dirty blocklist head */
52 	long		v_numoutput;		/* num of writes in progress */
53 	enum vtype	v_type;			/* vnode type */
54 	union {
55 		struct mount	*vu_mountedhere;/* ptr to mounted vfs (VDIR) */
56 		struct socket	*vu_socket;	/* unix ipc (VSOCK) */
57 		caddr_t		vu_vmdata;	/* private data for vm */
58 		struct specinfo	*vu_specinfo;	/* device (VCHR, VBLK) */
59 		struct fifoinfo	*vu_fifoinfo;	/* fifo (VFIFO) */
60 	} v_un;
61 	enum vtagtype	v_tag;			/* type of underlying data */
62 	char v_data[VN_MAXPRIVATE];		/* private data for fs */
63 };
64 #define v_mountedhere v_un.vu_mountedhere
65 #define v_socket v_un.vu_socket
66 #define v_vmdata v_un.vu_vmdata
67 #define v_specinfo v_un.vu_specinfo
68 #define v_fifoinfo v_un.vu_fifoinfo
69 
70 /*
71  * vnode flags.
72  */
73 #define	VROOT		0x0001	/* root of its file system */
74 #define	VTEXT		0x0002	/* vnode is a pure text prototype */
75 #define	VSYSTEM		0x0004	/* vnode being used by kernel */
76 #define	VXLOCK		0x0100	/* vnode is locked to change underlying type */
77 #define	VXWANT		0x0200	/* process is waiting for vnode */
78 #define	VBWAIT		0x0400	/* waiting for output to complete */
79 #define	VALIASED	0x0800	/* vnode has an alias */
80 
81 /*
82  * Operations on vnodes.
83  */
84 struct vnodeops {
85 	int	(*vn_lookup)(		/* ndp */ );
86 	int	(*vn_create)(		/* ndp, fflags, vap, cred */ );
87 	int	(*vn_mknod)(		/* ndp, vap, cred */ );
88 	int	(*vn_open)(		/* vp, fflags, cred */ );
89 	int	(*vn_close)(		/* vp, fflags, cred */ );
90 	int	(*vn_access)(		/* vp, fflags, cred */ );
91 	int	(*vn_getattr)(		/* vp, vap, cred */ );
92 	int	(*vn_setattr)(		/* vp, vap, cred */ );
93 
94 	int	(*vn_read)(		/* vp, uiop, offp, ioflag, cred */ );
95 	int	(*vn_write)(		/* vp, uiop, offp, ioflag, cred */ );
96 	int	(*vn_ioctl)(		/* vp, com, data, fflag, cred */ );
97 	int	(*vn_select)(		/* vp, which, cred */ );
98 	int	(*vn_mmap)(		/* vp, ..., cred */ );
99 	int	(*vn_fsync)(		/* vp, fflags, cred */ );
100 	int	(*vn_seek)(		/* vp, (old)offp, off, whence */ );
101 
102 	int	(*vn_remove)(		/* ndp */ );
103 	int	(*vn_link)(		/* vp, ndp */ );
104 	int	(*vn_rename)(		/* ndp, ndp */ );
105 	int	(*vn_mkdir)(		/* ndp, vap */ );
106 	int	(*vn_rmdir)(		/* ndp */ );
107 	int	(*vn_symlink)(		/* ndp, vap, nm */ );
108 	int	(*vn_readdir)(		/* vp, uiop, cred, eofflagp */ );
109 	int	(*vn_readlink)(		/* vp, uiop, cred */ );
110 
111 	int	(*vn_abortop)(		/* ndp */ );
112 	int	(*vn_inactive)(		/* vp */ );
113 	int	(*vn_reclaim)(		/* vp */ );
114 	int	(*vn_lock)(		/* vp */ );
115 	int	(*vn_unlock)(		/* vp */ );
116 
117 	int	(*vn_bmap)(		/* vp, bn, vpp, bnp */ );
118 	int	(*vn_strategy)(		/* bp */ );
119 
120 	int	(*vn_print)(		/* vp */ );
121 	int	(*vn_islocked)(		/* vp */ );
122 	int	(*vn_advlock)(		/* vp, proc, op, lck, flg */ );
123 };
124 
125 /* Macros to call the vnode ops */
126 #define	VOP_LOOKUP(v,n)		(*((v)->v_op->vn_lookup))((v),(n))
127 #define	VOP_CREATE(n,a)		(*((n)->ni_dvp->v_op->vn_create))((n),(a))
128 #define	VOP_MKNOD(n,a,c)	(*((n)->ni_dvp->v_op->vn_mknod))((n),(a),(c))
129 #define	VOP_OPEN(v,f,c)		(*((v)->v_op->vn_open))((v),(f),(c))
130 #define	VOP_CLOSE(v,f,c)	(*((v)->v_op->vn_close))((v),(f),(c))
131 #define	VOP_ACCESS(v,f,c)	(*((v)->v_op->vn_access))((v),(f),(c))
132 #define	VOP_GETATTR(v,a,c)	(*((v)->v_op->vn_getattr))((v),(a),(c))
133 #define	VOP_SETATTR(v,a,c)	(*((v)->v_op->vn_setattr))((v),(a),(c))
134 #define	VOP_READ(v,u,i,c)	(*((v)->v_op->vn_read))((v),(u),(i),(c))
135 #define	VOP_WRITE(v,u,i,c)	(*((v)->v_op->vn_write))((v),(u),(i),(c))
136 #define	VOP_IOCTL(v,o,d,f,c)	(*((v)->v_op->vn_ioctl))((v),(o),(d),(f),(c))
137 #define	VOP_SELECT(v,w,f,c)	(*((v)->v_op->vn_select))((v),(w),(f),(c))
138 #define	VOP_MMAP(v,c)		(*((v)->v_op->vn_mmap))((v),(c))
139 #define	VOP_FSYNC(v,f,c,w)	(*((v)->v_op->vn_fsync))((v),(f),(c),(w))
140 #define	VOP_SEEK(v,p,o,w)	(*((v)->v_op->vn_seek))((v),(p),(o),(w))
141 #define	VOP_REMOVE(n)		(*((n)->ni_dvp->v_op->vn_remove))(n)
142 #define	VOP_LINK(v,n)		(*((n)->ni_dvp->v_op->vn_link))((v),(n))
143 #define	VOP_RENAME(s,t)		(*((s)->ni_dvp->v_op->vn_rename))((s),(t))
144 #define	VOP_MKDIR(n,a)		(*((n)->ni_dvp->v_op->vn_mkdir))((n),(a))
145 #define	VOP_RMDIR(n)		(*((n)->ni_dvp->v_op->vn_rmdir))(n)
146 #define	VOP_SYMLINK(n,a,m)	(*((n)->ni_dvp->v_op->vn_symlink))((n),(a),(m))
147 #define	VOP_READDIR(v,u,c,e)	(*((v)->v_op->vn_readdir))((v),(u),(c),(e))
148 #define	VOP_READLINK(v,u,c)	(*((v)->v_op->vn_readlink))((v),(u),(c))
149 #define	VOP_ABORTOP(n)		(*((n)->ni_dvp->v_op->vn_abortop))(n)
150 #define	VOP_INACTIVE(v)		(*((v)->v_op->vn_inactive))(v)
151 #define	VOP_RECLAIM(v)		(*((v)->v_op->vn_reclaim))(v)
152 #define	VOP_LOCK(v)		(*((v)->v_op->vn_lock))(v)
153 #define	VOP_UNLOCK(v)		(*((v)->v_op->vn_unlock))(v)
154 #define	VOP_BMAP(v,s,p,n)	(*((v)->v_op->vn_bmap))((v),(s),(p),(n))
155 #define	VOP_STRATEGY(b)		(*((b)->b_vp->v_op->vn_strategy))(b)
156 #define	VOP_PRINT(v)		(*((v)->v_op->vn_print))(v)
157 #define	VOP_ISLOCKED(v)		(*((v)->v_op->vn_islocked))(v)
158 #define	VOP_ADVLOCK(v,p,o,l,f)	(*((v)->v_op->vn_advlock))((v),(p),(o),(l),(f))
159 
160 /*
161  * flags for ioflag
162  */
163 #define IO_UNIT		0x01		/* do I/O as atomic unit */
164 #define IO_APPEND	0x02		/* append write to end */
165 #define IO_SYNC		0x04		/* do I/O synchronously */
166 #define	IO_NODELOCKED	0x08		/* underlying node already locked */
167 #define	IO_NDELAY	0x10		/* FNDELAY flag set in file table */
168 
169 /*
170  * Vnode attributes.  A field value of VNOVAL
171  * represents a field whose value is unavailable
172  * (getattr) or which is not to be changed (setattr).
173  */
174 struct vattr {
175 	enum vtype	va_type;	/* vnode type (for create) */
176 	u_short		va_mode;	/* files access mode and type */
177 	short		va_nlink;	/* number of references to file */
178 	uid_t		va_uid;		/* owner user id */
179 	gid_t		va_gid;		/* owner group id */
180 	long		va_fsid;	/* file system id (dev for now) */
181 	long		va_fileid;	/* file id */
182 	u_quad		va_qsize;	/* file size in bytes */
183 	long		va_blocksize;	/* blocksize preferred for i/o */
184 	struct timeval	va_atime;	/* time of last access */
185 	struct timeval	va_mtime;	/* time of last modification */
186 	struct timeval	va_ctime;	/* time file changed */
187 	u_long		va_gen;		/* generation number of file */
188 	u_long		va_flags;	/* flags defined for file */
189 	dev_t		va_rdev;	/* device the special file represents */
190 	u_quad		va_qbytes;	/* bytes of disk space held by file */
191 };
192 #if BYTE_ORDER == LITTLE_ENDIAN
193 #define	va_size		va_qsize.val[0]
194 #define	va_size_rsv	va_qsize.val[1]
195 #define	va_bytes	va_qbytes.val[0]
196 #define	va_bytes_rsv	va_qbytes.val[1]
197 #else
198 #define	va_size		va_qsize.val[1]
199 #define	va_size_rsv	va_qsize.val[0]
200 #define	va_bytes	va_qbytes.val[1]
201 #define	va_bytes_rsv	va_qbytes.val[0]
202 #endif
203 
204 /*
205  *  Modes. Some values same as Ixxx entries from inode.h for now
206  */
207 #define	VSUID	04000		/* set user id on execution */
208 #define	VSGID	02000		/* set group id on execution */
209 #define	VSVTX	01000		/* save swapped text even after use */
210 #define	VREAD	0400		/* read, write, execute permissions */
211 #define	VWRITE	0200
212 #define	VEXEC	0100
213 
214 /*
215  * Token indicating no attribute value yet assigned
216  */
217 #define VNOVAL	((unsigned)0xffffffff)
218 
219 #ifdef KERNEL
220 /*
221  * public vnode manipulation functions
222  */
223 extern int vn_open();			/* open vnode */
224 extern int vn_rdwr();			/* read or write vnode */
225 extern int vn_close();			/* close vnode */
226 extern void vattr_null();		/* set attributes to null */
227 extern int getnewvnode();		/* allocate a new vnode */
228 extern int bdevvp();			/* allocate a new special dev vnode */
229 extern struct vnode *checkalias();	/* check for special device aliases */
230 extern int vcount();			/* total references to a device */
231 extern int vget();			/* get first reference to a vnode */
232 extern void vref();			/* increase reference to a vnode */
233 extern void vput();			/* unlock and release vnode */
234 extern void vrele();			/* release vnode */
235 extern void vgone();			/* completely recycle vnode */
236 extern void vgoneall();			/* recycle vnode and all its aliases */
237 
238 /*
239  * Flags to various vnode functions.
240  */
241 #define	SKIPSYSTEM	0x0001		/* vflush: skip vnodes marked VSYSTEM */
242 #define	FORCECLOSE	0x0002		/* vflush: force file closeure */
243 #define	DOCLOSE		0x0004		/* vclean: close active files */
244 
245 #ifndef DIAGNOSTIC
246 #define VREF(vp)    (vp)->v_usecount++	/* increase reference to a vnode */
247 #define VHOLD(vp)   (vp)->v_holdcnt++	/* increase buf or page ref to vnode */
248 #define HOLDRELE(vp) (vp)->v_holdcnt--	/* decrease buf or page ref to vnode */
249 #define	VATTR_NULL(vap) *(vap) = va_null /* initialize a vattr stucture */
250 #else /* DIAGNOSTIC */
251 #define VREF(vp)    vref(vp)
252 #define VHOLD(vp)   vhold(vp)
253 #define HOLDRELE(vp) holdrele(vp)
254 #define	VATTR_NULL(vap) vattr_null(vap)
255 #endif
256 
257 #define	NULLVP	((struct vnode *)0)
258 
259 /*
260  * Global vnode data.
261  */
262 extern	struct vnode *rootdir;		/* root (i.e. "/") vnode */
263 extern	int desiredvnodes;		/* number of vnodes desired */
264 extern	struct vattr va_null;		/* predefined null vattr structure */
265 #endif
266