vnode.h revision 3304
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 1.9 1994/09/25 19:34:02 phk 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#ifdef VFS_LKM 215#define VNODEOP_SET(f) DATA_SET(MODVNOPS,f) 216#else 217#define VNODEOP_SET(f) DATA_SET(vfs_opv_descs_,f) 218#endif 219 220/* 221 * Global vnode data. 222 */ 223extern struct vnode *rootvnode; /* root (i.e. "/") vnode */ 224extern int desiredvnodes; /* number of vnodes desired */ 225extern struct vattr va_null; /* predefined null vattr structure */ 226 227/* 228 * Macro/function to check for client cache inconsistency w.r.t. leasing. 229 */ 230#define LEASE_READ 0x1 /* Check lease for readers */ 231#define LEASE_WRITE 0x2 /* Check lease for modifiers */ 232 233extern void (*lease_check) __P((struct vnode *vp, struct proc *p, 234 struct ucred *ucred, int flag)); 235extern void (*lease_updatetime) __P((int deltat)); 236 237#ifdef NFS 238#define LEASE_CHECK(vp, p, cred, flag) lease_check((vp), (p), (cred), (flag)) 239#define LEASE_UPDATETIME(dt) lease_updatetime(dt) 240#else 241#define LEASE_CHECK(vp, p, cred, flag) \ 242 do { if(lease_check) lease_check((vp), (p), (cred), (flag)); } while(0) 243#define LEASE_UPDATETIME(dt) \ 244 do { if(lease_updatetime) lease_updatetime(dt); } while(0) 245#endif /* NFS */ 246#endif /* KERNEL */ 247 248 249/* 250 * Mods for exensibility. 251 */ 252 253/* 254 * Flags for vdesc_flags: 255 */ 256#define VDESC_MAX_VPS 16 257/* Low order 16 flag bits are reserved for willrele flags for vp arguments. */ 258#define VDESC_VP0_WILLRELE 0x0001 259#define VDESC_VP1_WILLRELE 0x0002 260#define VDESC_VP2_WILLRELE 0x0004 261#define VDESC_VP3_WILLRELE 0x0008 262#define VDESC_NOMAP_VPP 0x0100 263#define VDESC_VPP_WILLRELE 0x0200 264 265/* 266 * VDESC_NO_OFFSET is used to identify the end of the offset list 267 * and in places where no such field exists. 268 */ 269#define VDESC_NO_OFFSET -1 270 271/* 272 * This structure describes the vnode operation taking place. 273 */ 274struct vnodeop_desc { 275 int vdesc_offset; /* offset in vector--first for speed */ 276 char *vdesc_name; /* a readable name for debugging */ 277 int vdesc_flags; /* VDESC_* flags */ 278 279 /* 280 * These ops are used by bypass routines to map and locate arguments. 281 * Creds and procs are not needed in bypass routines, but sometimes 282 * they are useful to (for example) transport layers. 283 * Nameidata is useful because it has a cred in it. 284 */ 285 int *vdesc_vp_offsets; /* list ended by VDESC_NO_OFFSET */ 286 int vdesc_vpp_offset; /* return vpp location */ 287 int vdesc_cred_offset; /* cred location, if any */ 288 int vdesc_proc_offset; /* proc location, if any */ 289 int vdesc_componentname_offset; /* if any */ 290 /* 291 * Finally, we've got a list of private data (about each operation) 292 * for each transport layer. (Support to manage this list is not 293 * yet part of BSD.) 294 */ 295 caddr_t *vdesc_transports; 296}; 297 298#ifdef KERNEL 299/* 300 * A list of all the operation descs. 301 */ 302extern struct vnodeop_desc *vnodeop_descs[]; 303 304 305/* 306 * This macro is very helpful in defining those offsets in the vdesc struct. 307 * 308 * This is stolen from X11R4. I ingored all the fancy stuff for 309 * Crays, so if you decide to port this to such a serious machine, 310 * you might want to consult Intrisics.h's XtOffset{,Of,To}. 311 */ 312#define VOPARG_OFFSET(p_type,field) \ 313 ((int) (((char *) (&(((p_type)NULL)->field))) - ((char *) NULL))) 314#define VOPARG_OFFSETOF(s_type,field) \ 315 VOPARG_OFFSET(s_type*,field) 316#define VOPARG_OFFSETTO(S_TYPE,S_OFFSET,STRUCT_P) \ 317 ((S_TYPE)(((char*)(STRUCT_P))+(S_OFFSET))) 318 319 320/* 321 * This structure is used to configure the new vnodeops vector. 322 */ 323struct vnodeopv_entry_desc { 324 struct vnodeop_desc *opve_op; /* which operation this is */ 325 int (*opve_impl)(); /* code implementing this operation */ 326}; 327struct vnodeopv_desc { 328 /* ptr to the ptr to the vector where op should go */ 329 int (***opv_desc_vector_p)(); 330 struct vnodeopv_entry_desc *opv_desc_ops; /* null terminated list */ 331}; 332 333/* 334 * A default routine which just returns an error. 335 */ 336int vn_default_error __P((void)); 337 338/* 339 * A generic structure. 340 * This can be used by bypass routines to identify generic arguments. 341 */ 342struct vop_generic_args { 343 struct vnodeop_desc *a_desc; 344 /* other random data follows, presumably */ 345}; 346 347/* 348 * VOCALL calls an op given an ops vector. We break it out because BSD's 349 * vclean changes the ops vector and then wants to call ops with the old 350 * vector. 351 */ 352#define VOCALL(OPSV,OFF,AP) (( *((OPSV)[(OFF)])) (AP)) 353 354/* 355 * This call works for vnodes in the kernel. 356 */ 357#define VCALL(VP,OFF,AP) VOCALL((VP)->v_op,(OFF),(AP)) 358#define VDESC(OP) (& __CONCAT(OP,_desc)) 359#define VOFFSET(OP) (VDESC(OP)->vdesc_offset) 360 361/* 362 * Finally, include the default set of vnode operations. 363 */ 364#include <vnode_if.h> 365 366/* 367 * Public vnode manipulation functions. 368 */ 369struct componentname; 370struct file; 371struct mount; 372struct nameidata; 373struct proc; 374struct stat; 375struct ucred; 376struct uio; 377struct vattr; 378struct vnode; 379struct vop_bwrite_args; 380 381int bdevvp __P((dev_t dev, struct vnode **vpp)); 382/* cache_* may belong in namei.h. */ 383void cache_enter __P((struct vnode *dvp, struct vnode *vp, 384 struct componentname *cnp)); 385int cache_lookup __P((struct vnode *dvp, struct vnode **vpp, 386 struct componentname *cnp)); 387void cache_purge __P((struct vnode *vp)); 388void cache_purgevfs __P((struct mount *mp)); 389int getnewvnode __P((enum vtagtype tag, 390 struct mount *mp, int (**vops)(), struct vnode **vpp)); 391int vinvalbuf __P((struct vnode *vp, int save, struct ucred *cred, 392 struct proc *p, int slpflag, int slptimeo)); 393void vattr_null __P((struct vattr *vap)); 394int vcount __P((struct vnode *vp)); 395int vget __P((struct vnode *vp, int lockflag)); 396void vgone __P((struct vnode *vp)); 397void vgoneall __P((struct vnode *vp)); 398int vn_bwrite __P((struct vop_bwrite_args *ap)); 399int vn_close __P((struct vnode *vp, 400 int flags, struct ucred *cred, struct proc *p)); 401int vn_closefile __P((struct file *fp, struct proc *p)); 402int vn_ioctl __P((struct file *fp, int com, caddr_t data, struct proc *p)); 403int vn_open __P((struct nameidata *ndp, int fmode, int cmode)); 404int vn_rdwr __P((enum uio_rw rw, struct vnode *vp, caddr_t base, 405 int len, off_t offset, enum uio_seg segflg, int ioflg, 406 struct ucred *cred, int *aresid, struct proc *p)); 407int vn_read __P((struct file *fp, struct uio *uio, struct ucred *cred)); 408int vn_select __P((struct file *fp, int which, struct proc *p)); 409int vn_stat __P((struct vnode *vp, struct stat *sb, struct proc *p)); 410int vn_write __P((struct file *fp, struct uio *uio, struct ucred *cred)); 411struct vnode * 412 checkalias __P((struct vnode *vp, dev_t nvp_rdev, struct mount *mp)); 413void vprint __P((char *, struct vnode *)); 414void vput __P((struct vnode *vp)); 415void vref __P((struct vnode *vp)); 416void vrele __P((struct vnode *vp)); 417 418void vfs_opv_init __P((struct vnodeopv_desc **)); 419#endif /* KERNEL */ 420 421#endif /* !_SYS_VNODE_H_ */ 422