vnode.h revision 2893
1/* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)vnode.h 8.7 (Berkeley) 2/4/94 34 * $Id: vnode.h,v 1.5 1994/09/15 20:24:29 bde Exp $ 35 */ 36 37#ifndef _SYS_VNODE_H_ 38#define _SYS_VNODE_H_ 39 40#include <sys/queue.h> 41 42/* 43 * The vnode is the focus of all file activity in UNIX. There is a 44 * unique vnode allocated for each active file, each current directory, 45 * each mounted-on file, text file, and the root. 46 */ 47 48/* 49 * Vnode types. VNON means no type. 50 */ 51enum vtype { VNON, VREG, VDIR, VBLK, VCHR, VLNK, VSOCK, VFIFO, VBAD }; 52 53/* 54 * Vnode tag types. 55 * These are for the benefit of external programs only (e.g., pstat) 56 * and should NEVER be inspected by the kernel. 57 */ 58enum vtagtype { 59 VT_NON, VT_UFS, VT_NFS, VT_MFS, VT_PC, VT_LFS, VT_LOFS, VT_FDESC, 60 VT_PORTAL, VT_NULL, VT_UMAP, VT_KERNFS, VT_PROCFS, VT_AFS, VT_ISOFS, 61 VT_UNION, VT_MSDOSFS 62}; 63 64/* 65 * Each underlying filesystem allocates its own private area and hangs 66 * it from v_data. If non-null, this area is freed in getnewvnode(). 67 */ 68LIST_HEAD(buflists, buf); 69 70struct vnode { 71 u_long v_flag; /* vnode flags (see below) */ 72 short v_usecount; /* reference count of users */ 73 short v_writecount; /* reference count of writers */ 74 long v_holdcnt; /* page & buffer references */ 75 daddr_t v_lastr; /* last read (read-ahead) */ 76 u_long v_id; /* capability identifier */ 77 struct mount *v_mount; /* ptr to vfs we are in */ 78 int (**v_op)(); /* vnode operations vector */ 79 TAILQ_ENTRY(vnode) v_freelist; /* vnode freelist */ 80 LIST_ENTRY(vnode) v_mntvnodes; /* vnodes for mount point */ 81 struct buflists v_cleanblkhd; /* clean blocklist head */ 82 struct buflists v_dirtyblkhd; /* dirty blocklist head */ 83 long v_numoutput; /* num of writes in progress */ 84 enum vtype v_type; /* vnode type */ 85 union { 86 struct mount *vu_mountedhere;/* ptr to mounted vfs (VDIR) */ 87 struct socket *vu_socket; /* unix ipc (VSOCK) */ 88 struct specinfo *vu_specinfo; /* device (VCHR, VBLK) */ 89 struct fifoinfo *vu_fifoinfo; /* fifo (VFIFO) */ 90 } v_un; 91 struct nqlease *v_lease; /* Soft reference to lease */ 92 daddr_t v_lastw; /* last write (write cluster) */ 93 daddr_t v_cstart; /* start block of cluster */ 94 daddr_t v_lasta; /* last allocation */ 95 int v_clen; /* length of current cluster */ 96 int v_ralen; /* Read-ahead length */ 97 daddr_t v_maxra; /* last readahead block */ 98 caddr_t v_vmdata; /* Place to store VM pager */ 99 enum vtagtype v_tag; /* type of underlying data */ 100 void *v_data; /* private data for fs */ 101}; 102#define v_mountedhere v_un.vu_mountedhere 103#define v_socket v_un.vu_socket 104#define v_specinfo v_un.vu_specinfo 105#define v_fifoinfo v_un.vu_fifoinfo 106 107/* 108 * Vnode flags. 109 */ 110#define VROOT 0x0001 /* root of its file system */ 111#define VTEXT 0x0002 /* vnode is a pure text prototype */ 112#define VSYSTEM 0x0004 /* vnode being used by kernel */ 113#define VXLOCK 0x0100 /* vnode is locked to change underlying type */ 114#define VXWANT 0x0200 /* process is waiting for vnode */ 115#define VBWAIT 0x0400 /* waiting for output to complete */ 116#define VALIASED 0x0800 /* vnode has an alias */ 117#define VDIROP 0x1000 /* LFS: vnode is involved in a directory op */ 118 119/* 120 * Vnode attributes. A field value of VNOVAL represents a field whose value 121 * is unavailable (getattr) or which is not to be changed (setattr). 122 */ 123struct vattr { 124 enum vtype va_type; /* vnode type (for create) */ 125 u_short va_mode; /* files access mode and type */ 126 short va_nlink; /* number of references to file */ 127 uid_t va_uid; /* owner user id */ 128 gid_t va_gid; /* owner group id */ 129 long va_fsid; /* file system id (dev for now) */ 130 long va_fileid; /* file id */ 131 u_quad_t va_size; /* file size in bytes */ 132 long va_blocksize; /* blocksize preferred for i/o */ 133 struct timespec va_atime; /* time of last access */ 134 struct timespec va_mtime; /* time of last modification */ 135 struct timespec va_ctime; /* time file changed */ 136 u_long va_gen; /* generation number of file */ 137 u_long va_flags; /* flags defined for file */ 138 dev_t va_rdev; /* device the special file represents */ 139 u_quad_t va_bytes; /* bytes of disk space held by file */ 140 u_quad_t va_filerev; /* file modification number */ 141 u_int va_vaflags; /* operations flags, see below */ 142 long va_spare; /* remain quad aligned */ 143}; 144 145/* 146 * Flags for va_cflags. 147 */ 148#define VA_UTIMES_NULL 0x01 /* utimes argument was NULL */ 149 150/* 151 * Flags for ioflag. 152 */ 153#define IO_UNIT 0x01 /* do I/O as atomic unit */ 154#define IO_APPEND 0x02 /* append write to end */ 155#define IO_SYNC 0x04 /* do I/O synchronously */ 156#define IO_NODELOCKED 0x08 /* underlying node already locked */ 157#define IO_NDELAY 0x10 /* FNDELAY flag set in file table */ 158 159/* 160 * Modes. Some values same as Ixxx entries from inode.h for now. 161 */ 162#define VSUID 04000 /* set user id on execution */ 163#define VSGID 02000 /* set group id on execution */ 164#define VSVTX 01000 /* save swapped text even after use */ 165#define VREAD 00400 /* read, write, execute permissions */ 166#define VWRITE 00200 167#define VEXEC 00100 168 169/* 170 * Token indicating no attribute value yet assigned. 171 */ 172#define VNOVAL (-1) 173 174#ifdef KERNEL 175/* 176 * Convert between vnode types and inode formats (since POSIX.1 177 * defines mode word of stat structure in terms of inode formats). 178 */ 179extern enum vtype iftovt_tab[]; 180extern int vttoif_tab[]; 181#define IFTOVT(mode) (iftovt_tab[((mode) & S_IFMT) >> 12]) 182#define VTTOIF(indx) (vttoif_tab[(int)(indx)]) 183#define MAKEIMODE(indx, mode) (int)(VTTOIF(indx) | (mode)) 184 185/* 186 * Flags to various vnode functions. 187 */ 188#define SKIPSYSTEM 0x0001 /* vflush: skip vnodes marked VSYSTEM */ 189#define FORCECLOSE 0x0002 /* vflush: force file closeure */ 190#define WRITECLOSE 0x0004 /* vflush: only close writeable files */ 191#define DOCLOSE 0x0008 /* vclean: close active files */ 192#define V_SAVE 0x0001 /* vinvalbuf: sync file first */ 193#define V_SAVEMETA 0x0002 /* vinvalbuf: leave indirect blocks */ 194 195#ifdef DIAGNOSTIC 196#define HOLDRELE(vp) holdrele(vp) 197#define VATTR_NULL(vap) vattr_null(vap) 198#define VHOLD(vp) vhold(vp) 199#define VREF(vp) vref(vp) 200 201void holdrele __P((struct vnode *)); 202void vattr_null __P((struct vattr *)); 203void vhold __P((struct vnode *)); 204void vref __P((struct vnode *)); 205#else 206#define HOLDRELE(vp) (vp)->v_holdcnt-- /* decrease buf or page ref */ 207#define VATTR_NULL(vap) (*(vap) = va_null) /* initialize a vattr */ 208#define VHOLD(vp) (vp)->v_holdcnt++ /* increase buf or page ref */ 209#define VREF(vp) (vp)->v_usecount++ /* increase reference */ 210#endif 211 212#define NULLVP ((struct vnode *)NULL) 213 214/* 215 * Global vnode data. 216 */ 217extern struct vnode *rootvnode; /* root (i.e. "/") vnode */ 218extern int desiredvnodes; /* number of vnodes desired */ 219extern struct vattr va_null; /* predefined null vattr structure */ 220 221/* 222 * Macro/function to check for client cache inconsistency w.r.t. leasing. 223 */ 224#define LEASE_READ 0x1 /* Check lease for readers */ 225#define LEASE_WRITE 0x2 /* Check lease for modifiers */ 226 227#ifdef NFS 228void lease_check __P((struct vnode *vp, struct proc *p, 229 struct ucred *ucred, int flag)); 230void lease_updatetime __P((int deltat)); 231#define LEASE_CHECK(vp, p, cred, flag) lease_check((vp), (p), (cred), (flag)) 232#define LEASE_UPDATETIME(dt) lease_updatetime(dt) 233#else 234#define LEASE_CHECK(vp, p, cred, flag) 235#define LEASE_UPDATETIME(dt) 236#endif /* NFS */ 237#endif /* KERNEL */ 238 239 240/* 241 * Mods for exensibility. 242 */ 243 244/* 245 * Flags for vdesc_flags: 246 */ 247#define VDESC_MAX_VPS 16 248/* Low order 16 flag bits are reserved for willrele flags for vp arguments. */ 249#define VDESC_VP0_WILLRELE 0x0001 250#define VDESC_VP1_WILLRELE 0x0002 251#define VDESC_VP2_WILLRELE 0x0004 252#define VDESC_VP3_WILLRELE 0x0008 253#define VDESC_NOMAP_VPP 0x0100 254#define VDESC_VPP_WILLRELE 0x0200 255 256/* 257 * VDESC_NO_OFFSET is used to identify the end of the offset list 258 * and in places where no such field exists. 259 */ 260#define VDESC_NO_OFFSET -1 261 262/* 263 * This structure describes the vnode operation taking place. 264 */ 265struct vnodeop_desc { 266 int vdesc_offset; /* offset in vector--first for speed */ 267 char *vdesc_name; /* a readable name for debugging */ 268 int vdesc_flags; /* VDESC_* flags */ 269 270 /* 271 * These ops are used by bypass routines to map and locate arguments. 272 * Creds and procs are not needed in bypass routines, but sometimes 273 * they are useful to (for example) transport layers. 274 * Nameidata is useful because it has a cred in it. 275 */ 276 int *vdesc_vp_offsets; /* list ended by VDESC_NO_OFFSET */ 277 int vdesc_vpp_offset; /* return vpp location */ 278 int vdesc_cred_offset; /* cred location, if any */ 279 int vdesc_proc_offset; /* proc location, if any */ 280 int vdesc_componentname_offset; /* if any */ 281 /* 282 * Finally, we've got a list of private data (about each operation) 283 * for each transport layer. (Support to manage this list is not 284 * yet part of BSD.) 285 */ 286 caddr_t *vdesc_transports; 287}; 288 289#ifdef KERNEL 290/* 291 * A list of all the operation descs. 292 */ 293extern struct vnodeop_desc *vnodeop_descs[]; 294 295 296/* 297 * This macro is very helpful in defining those offsets in the vdesc struct. 298 * 299 * This is stolen from X11R4. I ingored all the fancy stuff for 300 * Crays, so if you decide to port this to such a serious machine, 301 * you might want to consult Intrisics.h's XtOffset{,Of,To}. 302 */ 303#define VOPARG_OFFSET(p_type,field) \ 304 ((int) (((char *) (&(((p_type)NULL)->field))) - ((char *) NULL))) 305#define VOPARG_OFFSETOF(s_type,field) \ 306 VOPARG_OFFSET(s_type*,field) 307#define VOPARG_OFFSETTO(S_TYPE,S_OFFSET,STRUCT_P) \ 308 ((S_TYPE)(((char*)(STRUCT_P))+(S_OFFSET))) 309 310 311/* 312 * This structure is used to configure the new vnodeops vector. 313 */ 314struct vnodeopv_entry_desc { 315 struct vnodeop_desc *opve_op; /* which operation this is */ 316 int (*opve_impl)(); /* code implementing this operation */ 317}; 318struct vnodeopv_desc { 319 /* ptr to the ptr to the vector where op should go */ 320 int (***opv_desc_vector_p)(); 321 struct vnodeopv_entry_desc *opv_desc_ops; /* null terminated list */ 322}; 323 324/* 325 * A default routine which just returns an error. 326 */ 327int vn_default_error __P((void)); 328 329/* 330 * A generic structure. 331 * This can be used by bypass routines to identify generic arguments. 332 */ 333struct vop_generic_args { 334 struct vnodeop_desc *a_desc; 335 /* other random data follows, presumably */ 336}; 337 338/* 339 * VOCALL calls an op given an ops vector. We break it out because BSD's 340 * vclean changes the ops vector and then wants to call ops with the old 341 * vector. 342 */ 343#define VOCALL(OPSV,OFF,AP) (( *((OPSV)[(OFF)])) (AP)) 344 345/* 346 * This call works for vnodes in the kernel. 347 */ 348#define VCALL(VP,OFF,AP) VOCALL((VP)->v_op,(OFF),(AP)) 349#define VDESC(OP) (& __CONCAT(OP,_desc)) 350#define VOFFSET(OP) (VDESC(OP)->vdesc_offset) 351 352/* 353 * Finally, include the default set of vnode operations. 354 */ 355#include <vnode_if.h> 356 357/* 358 * Public vnode manipulation functions. 359 */ 360struct componentname; 361struct file; 362struct mount; 363struct nameidata; 364struct proc; 365struct stat; 366struct ucred; 367struct uio; 368struct vattr; 369struct vnode; 370struct vop_bwrite_args; 371 372int bdevvp __P((dev_t dev, struct vnode **vpp)); 373/* cache_* may belong in namei.h. */ 374void cache_enter __P((struct vnode *dvp, struct vnode *vp, 375 struct componentname *cnp)); 376int cache_lookup __P((struct vnode *dvp, struct vnode **vpp, 377 struct componentname *cnp)); 378void cache_purge __P((struct vnode *vp)); 379int getnewvnode __P((enum vtagtype tag, 380 struct mount *mp, int (**vops)(), struct vnode **vpp)); 381int vinvalbuf __P((struct vnode *vp, int save, struct ucred *cred, 382 struct proc *p, int slpflag, int slptimeo)); 383void vattr_null __P((struct vattr *vap)); 384int vcount __P((struct vnode *vp)); 385int vget __P((struct vnode *vp, int lockflag)); 386void vgone __P((struct vnode *vp)); 387void vgoneall __P((struct vnode *vp)); 388int vn_bwrite __P((struct vop_bwrite_args *ap)); 389int vn_close __P((struct vnode *vp, 390 int flags, struct ucred *cred, struct proc *p)); 391int vn_closefile __P((struct file *fp, struct proc *p)); 392int vn_ioctl __P((struct file *fp, int com, caddr_t data, struct proc *p)); 393int vn_open __P((struct nameidata *ndp, int fmode, int cmode)); 394int vn_rdwr __P((enum uio_rw rw, struct vnode *vp, caddr_t base, 395 int len, off_t offset, enum uio_seg segflg, int ioflg, 396 struct ucred *cred, int *aresid, struct proc *p)); 397int vn_read __P((struct file *fp, struct uio *uio, struct ucred *cred)); 398int vn_select __P((struct file *fp, int which, struct proc *p)); 399int vn_stat __P((struct vnode *vp, struct stat *sb, struct proc *p)); 400int vn_write __P((struct file *fp, struct uio *uio, struct ucred *cred)); 401struct vnode * 402 checkalias __P((struct vnode *vp, dev_t nvp_rdev, struct mount *mp)); 403void vprint __P((char *, struct vnode *)); 404void vput __P((struct vnode *vp)); 405void vref __P((struct vnode *vp)); 406void vrele __P((struct vnode *vp)); 407#endif /* KERNEL */ 408 409#endif /* !_SYS_VNODE_H_ */ 410