vnode.h revision 18990
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 1.35 1996/10/15 19:22:46 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, VT_DEVFS, VT_TFS 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 70typedef int vop_t __P((void *)); 71struct vm_object; 72 73struct vnode { 74 u_long v_flag; /* vnode flags (see below) */ 75 int v_usecount; /* reference count of users */ 76 int v_writecount; /* reference count of writers */ 77 int v_holdcnt; /* page & buffer references */ 78 daddr_t v_lastr; /* last read (read-ahead) */ 79 u_long v_id; /* capability identifier */ 80 struct mount *v_mount; /* ptr to vfs we are in */ 81 vop_t **v_op; /* vnode operations vector */ 82 TAILQ_ENTRY(vnode) v_freelist; /* vnode freelist */ 83 LIST_ENTRY(vnode) v_mntvnodes; /* vnodes for mount point */ 84 struct buflists v_cleanblkhd; /* clean blocklist head */ 85 struct buflists v_dirtyblkhd; /* dirty blocklist head */ 86 long v_numoutput; /* num of writes in progress */ 87 enum vtype v_type; /* vnode type */ 88 union { 89 struct mount *vu_mountedhere;/* ptr to mounted vfs (VDIR) */ 90 struct socket *vu_socket; /* unix ipc (VSOCK) */ 91 struct specinfo *vu_specinfo; /* device (VCHR, VBLK) */ 92 struct fifoinfo *vu_fifoinfo; /* fifo (VFIFO) */ 93 } v_un; 94 struct nqlease *v_lease; /* Soft reference to lease */ 95 daddr_t v_lastw; /* last write (write cluster) */ 96 daddr_t v_cstart; /* start block of cluster */ 97 daddr_t v_lasta; /* last allocation */ 98 int v_clen; /* length of current cluster */ 99 int v_ralen; /* Read-ahead length */ 100 int v_usage; /* Vnode usage counter */ 101 daddr_t v_maxra; /* last readahead block */ 102 struct vm_object *v_object; /* Place to store VM object */ 103 enum vtagtype v_tag; /* type of underlying data */ 104 void *v_data; /* private data for fs */ 105}; 106#define v_mountedhere v_un.vu_mountedhere 107#define v_socket v_un.vu_socket 108#define v_specinfo v_un.vu_specinfo 109#define v_fifoinfo v_un.vu_fifoinfo 110 111/* 112 * Vnode flags. 113 */ 114#define VROOT 0x0001 /* root of its file system */ 115#define VTEXT 0x0002 /* vnode is a pure text prototype */ 116#define VSYSTEM 0x0004 /* vnode being used by kernel */ 117#define VOLOCK 0x0008 /* vnode is locked waiting for an object */ 118#define VOWANT 0x0010 /* a process is waiting for VOLOCK */ 119#define VXLOCK 0x0100 /* vnode is locked to change underlying type */ 120#define VXWANT 0x0200 /* process is waiting for vnode */ 121#define VBWAIT 0x0400 /* waiting for output to complete */ 122#define VALIASED 0x0800 /* vnode has an alias */ 123#define VDIROP 0x1000 /* LFS: vnode is involved in a directory op */ 124#define VVMIO 0x2000 /* VMIO flag */ 125#define VNINACT 0x4000 /* LFS: skip ufs_inactive() in lfs_vunref */ 126#define VAGE 0x8000 /* Insert vnode at head of free list */ 127 128/* 129 * Vnode attributes. A field value of VNOVAL represents a field whose value 130 * is unavailable (getattr) or which is not to be changed (setattr). 131 */ 132struct vattr { 133 enum vtype va_type; /* vnode type (for create) */ 134 u_short va_mode; /* files access mode and type */ 135 short va_nlink; /* number of references to file */ 136 uid_t va_uid; /* owner user id */ 137 gid_t va_gid; /* owner group id */ 138 long va_fsid; /* file system id (dev for now) */ 139 long va_fileid; /* file id */ 140 u_quad_t va_size; /* file size in bytes */ 141 long va_blocksize; /* blocksize preferred for i/o */ 142 struct timespec va_atime; /* time of last access */ 143 struct timespec va_mtime; /* time of last modification */ 144 struct timespec va_ctime; /* time file changed */ 145 u_long va_gen; /* generation number of file */ 146 u_long va_flags; /* flags defined for file */ 147 dev_t va_rdev; /* device the special file represents */ 148 u_quad_t va_bytes; /* bytes of disk space held by file */ 149 u_quad_t va_filerev; /* file modification number */ 150 u_int va_vaflags; /* operations flags, see below */ 151 long va_spare; /* remain quad aligned */ 152}; 153 154/* 155 * Flags for va_cflags. 156 */ 157#define VA_UTIMES_NULL 0x01 /* utimes argument was NULL */ 158 159/* 160 * Flags for ioflag. 161 */ 162#define IO_UNIT 0x01 /* do I/O as atomic unit */ 163#define IO_APPEND 0x02 /* append write to end */ 164#define IO_SYNC 0x04 /* do I/O synchronously */ 165#define IO_NODELOCKED 0x08 /* underlying node already locked */ 166#define IO_NDELAY 0x10 /* FNDELAY flag set in file table */ 167#define IO_VMIO 0x20 /* data already in VMIO space */ 168 169/* 170 * Modes. Some values same as Ixxx entries from inode.h for now. 171 */ 172#define VSUID 04000 /* set user id on execution */ 173#define VSGID 02000 /* set group id on execution */ 174#define VSVTX 01000 /* save swapped text even after use */ 175#define VREAD 00400 /* read, write, execute permissions */ 176#define VWRITE 00200 177#define VEXEC 00100 178 179/* 180 * Token indicating no attribute value yet assigned. 181 */ 182#define VNOVAL (-1) 183 184#ifdef KERNEL 185/* 186 * Convert between vnode types and inode formats (since POSIX.1 187 * defines mode word of stat structure in terms of inode formats). 188 */ 189extern enum vtype iftovt_tab[]; 190extern int vttoif_tab[]; 191#define IFTOVT(mode) (iftovt_tab[((mode) & S_IFMT) >> 12]) 192#define VTTOIF(indx) (vttoif_tab[(int)(indx)]) 193#define MAKEIMODE(indx, mode) (int)(VTTOIF(indx) | (mode)) 194 195/* 196 * Flags to various vnode functions. 197 */ 198#define SKIPSYSTEM 0x0001 /* vflush: skip vnodes marked VSYSTEM */ 199#define FORCECLOSE 0x0002 /* vflush: force file closure */ 200#define WRITECLOSE 0x0004 /* vflush: only close writable files */ 201#define DOCLOSE 0x0008 /* vclean: close active files */ 202#define V_SAVE 0x0001 /* vinvalbuf: sync file first */ 203#define V_SAVEMETA 0x0002 /* vinvalbuf: leave indirect blocks */ 204 205#ifdef DIAGNOSTIC 206#define HOLDRELE(vp) holdrele(vp) 207#define VATTR_NULL(vap) vattr_null(vap) 208#define VHOLD(vp) vhold(vp) 209#define VREF(vp) vref(vp) 210 211void holdrele __P((struct vnode *)); 212void vhold __P((struct vnode *)); 213#else 214#define HOLDRELE(vp) (vp)->v_holdcnt-- /* decrease buf or page ref */ 215#define VATTR_NULL(vap) (*(vap) = va_null) /* initialize a vattr */ 216#define VHOLD(vp) (vp)->v_holdcnt++ /* increase buf or page ref */ 217#define VREF(vp) vref(vp) /* increase reference */ 218#endif 219 220#define NULLVP ((struct vnode *)NULL) 221 222#ifdef VFS_LKM 223#define VNODEOP_SET(f) DATA_SET(MODVNOPS,f) 224#else 225#define VNODEOP_SET(f) DATA_SET(vfs_opv_descs_,f) 226#endif 227 228/* 229 * Global vnode data. 230 */ 231extern struct vnode *rootvnode; /* root (i.e. "/") vnode */ 232extern int desiredvnodes; /* number of vnodes desired */ 233extern int extravnodes; /* extra vnodes to allocate at boot */ 234extern int prtactive; /* nonzero to call vprint() */ 235extern struct vattr va_null; /* predefined null vattr structure */ 236 237/* 238 * Macro/function to check for client cache inconsistency w.r.t. leasing. 239 */ 240#define LEASE_READ 0x1 /* Check lease for readers */ 241#define LEASE_WRITE 0x2 /* Check lease for modifiers */ 242 243extern void (*lease_check) __P((struct vnode *vp, struct proc *p, 244 struct ucred *ucred, int flag)); 245extern void (*lease_updatetime) __P((int deltat)); 246 247#ifdef NFS 248#ifdef NQNFS 249#define LEASE_CHECK(vp, p, cred, flag) lease_check((vp), (p), (cred), (flag)) 250#define LEASE_UPDATETIME(dt) lease_updatetime(dt) 251#else 252#define LEASE_CHECK(vp, p, cred, flag) 253#define LEASE_UPDATETIME(dt) 254#endif /* NQNFS */ 255#else 256#define LEASE_CHECK(vp, p, cred, flag) \ 257 do { if(lease_check) lease_check((vp), (p), (cred), (flag)); } while(0) 258#define LEASE_UPDATETIME(dt) \ 259 do { if(lease_updatetime) lease_updatetime(dt); } while(0) 260#endif /* NFS */ 261#endif /* KERNEL */ 262 263 264/* 265 * Mods for extensibility. 266 */ 267 268/* 269 * Flags for vdesc_flags: 270 */ 271#define VDESC_MAX_VPS 16 272/* Low order 16 flag bits are reserved for willrele flags for vp arguments. */ 273#define VDESC_VP0_WILLRELE 0x0001 274#define VDESC_VP1_WILLRELE 0x0002 275#define VDESC_VP2_WILLRELE 0x0004 276#define VDESC_VP3_WILLRELE 0x0008 277#define VDESC_NOMAP_VPP 0x0100 278#define VDESC_VPP_WILLRELE 0x0200 279 280/* 281 * VDESC_NO_OFFSET is used to identify the end of the offset list 282 * and in places where no such field exists. 283 */ 284#define VDESC_NO_OFFSET -1 285 286/* 287 * This structure describes the vnode operation taking place. 288 */ 289struct vnodeop_desc { 290 int vdesc_offset; /* offset in vector--first for speed */ 291 char *vdesc_name; /* a readable name for debugging */ 292 int vdesc_flags; /* VDESC_* flags */ 293 294 /* 295 * These ops are used by bypass routines to map and locate arguments. 296 * Creds and procs are not needed in bypass routines, but sometimes 297 * they are useful to (for example) transport layers. 298 * Nameidata is useful because it has a cred in it. 299 */ 300 int *vdesc_vp_offsets; /* list ended by VDESC_NO_OFFSET */ 301 int vdesc_vpp_offset; /* return vpp location */ 302 int vdesc_cred_offset; /* cred location, if any */ 303 int vdesc_proc_offset; /* proc location, if any */ 304 int vdesc_componentname_offset; /* if any */ 305 /* 306 * Finally, we've got a list of private data (about each operation) 307 * for each transport layer. (Support to manage this list is not 308 * yet part of BSD.) 309 */ 310 caddr_t *vdesc_transports; 311}; 312 313#ifdef KERNEL 314/* 315 * A list of all the operation descs. 316 */ 317extern struct vnodeop_desc *vnodeop_descs[]; 318 319 320/* 321 * This macro is very helpful in defining those offsets in the vdesc struct. 322 * 323 * This is stolen from X11R4. I ignored all the fancy stuff for 324 * Crays, so if you decide to port this to such a serious machine, 325 * you might want to consult Intrinsic.h's XtOffset{,Of,To}. 326 */ 327#define VOPARG_OFFSET(p_type,field) \ 328 ((int) (((char *) (&(((p_type)NULL)->field))) - ((char *) NULL))) 329#define VOPARG_OFFSETOF(s_type,field) \ 330 VOPARG_OFFSET(s_type*,field) 331#define VOPARG_OFFSETTO(S_TYPE,S_OFFSET,STRUCT_P) \ 332 ((S_TYPE)(((char*)(STRUCT_P))+(S_OFFSET))) 333 334 335/* 336 * This structure is used to configure the new vnodeops vector. 337 */ 338struct vnodeopv_entry_desc { 339 struct vnodeop_desc *opve_op; /* which operation this is */ 340 vop_t *opve_impl; /* code implementing this operation */ 341}; 342struct vnodeopv_desc { 343 /* ptr to the ptr to the vector where op should go */ 344 vop_t ***opv_desc_vector_p; 345 struct vnodeopv_entry_desc *opv_desc_ops; /* null terminated list */ 346}; 347 348/* 349 * A default routine which just returns an error. 350 */ 351int vn_default_error __P((void)); 352 353/* 354 * A generic structure. 355 * This can be used by bypass routines to identify generic arguments. 356 */ 357struct vop_generic_args { 358 struct vnodeop_desc *a_desc; 359 /* other random data follows, presumably */ 360}; 361 362/* 363 * VOCALL calls an op given an ops vector. We break it out because BSD's 364 * vclean changes the ops vector and then wants to call ops with the old 365 * vector. 366 */ 367#define VOCALL(OPSV,OFF,AP) (( *((OPSV)[(OFF)])) (AP)) 368 369/* 370 * This call works for vnodes in the kernel. 371 */ 372#define VCALL(VP,OFF,AP) VOCALL((VP)->v_op,(OFF),(AP)) 373#define VDESC(OP) (& __CONCAT(OP,_desc)) 374#define VOFFSET(OP) (VDESC(OP)->vdesc_offset) 375 376/* 377 * Finally, include the default set of vnode operations. 378 */ 379#include "vnode_if.h" 380 381/* 382 * Public vnode manipulation functions. 383 */ 384struct componentname; 385struct file; 386struct mount; 387struct nameidata; 388struct proc; 389struct stat; 390struct ucred; 391struct uio; 392struct vattr; 393struct vnode; 394struct vop_bwrite_args; 395 396int bdevvp __P((dev_t dev, struct vnode **vpp)); 397/* cache_* may belong in namei.h. */ 398void cache_enter __P((struct vnode *dvp, struct vnode *vp, 399 struct componentname *cnp)); 400int cache_lookup __P((struct vnode *dvp, struct vnode **vpp, 401 struct componentname *cnp)); 402void cache_purge __P((struct vnode *vp)); 403void cache_purgevfs __P((struct mount *mp)); 404struct vnode * 405 checkalias __P((struct vnode *vp, dev_t nvp_rdev, struct mount *mp)); 406int getnewvnode __P((enum vtagtype tag, 407 struct mount *mp, vop_t **vops, struct vnode **vpp)); 408void insmntque __P((struct vnode *vp, struct mount *mp)); 409void vattr_null __P((struct vattr *vap)); 410int vcount __P((struct vnode *vp)); 411int vfinddev __P((dev_t dev, enum vtype type, struct vnode **vpp)); 412void vfs_opv_init __P((struct vnodeopv_desc **them)); 413int vget __P((struct vnode *vp, int lockflag)); 414void vgone __P((struct vnode *vp)); 415void vgoneall __P((struct vnode *vp)); 416int vinvalbuf __P((struct vnode *vp, int save, struct ucred *cred, 417 struct proc *p, int slpflag, int slptimeo)); 418int vn_bwrite __P((struct vop_bwrite_args *ap)); 419int vn_close __P((struct vnode *vp, 420 int flags, struct ucred *cred, struct proc *p)); 421int vn_open __P((struct nameidata *ndp, int fmode, int cmode)); 422int vn_rdwr __P((enum uio_rw rw, struct vnode *vp, caddr_t base, 423 int len, off_t offset, enum uio_seg segflg, int ioflg, 424 struct ucred *cred, int *aresid, struct proc *p)); 425int vn_stat __P((struct vnode *vp, struct stat *sb, struct proc *p)); 426int vfs_object_create __P((struct vnode *vp, struct proc *p, 427 struct ucred *cred, int waslocked)); 428int vn_writechk __P((struct vnode *vp)); 429void vprint __P((char *label, struct vnode *vp)); 430void vput __P((struct vnode *vp)); 431void vref __P((struct vnode *vp)); 432void vrele __P((struct vnode *vp)); 433#endif /* KERNEL */ 434 435#endif /* !_SYS_VNODE_H_ */ 436