1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)vnode.h 8.17 (Berkeley) 05/20/95 8 */ 9 10 #include <sys/lock.h> 11 #include <sys/queue.h> 12 13 /* 14 * The vnode is the focus of all file activity in UNIX. There is a 15 * unique vnode allocated for each active file, each current directory, 16 * each mounted-on file, text file, and the root. 17 */ 18 19 /* 20 * Vnode types. VNON means no type. 21 */ 22 enum vtype { VNON, VREG, VDIR, VBLK, VCHR, VLNK, VSOCK, VFIFO, VBAD }; 23 24 /* 25 * Vnode tag types. 26 * These are for the benefit of external programs only (e.g., pstat) 27 * and should NEVER be inspected by the kernel. 28 */ 29 enum vtagtype { 30 VT_NON, VT_UFS, VT_NFS, VT_MFS, VT_PC, VT_LFS, VT_LOFS, VT_FDESC, 31 VT_PORTAL, VT_NULL, VT_UMAP, VT_KERNFS, VT_PROCFS, VT_AFS, VT_ISOFS, 32 VT_UNION 33 }; 34 35 /* 36 * Each underlying filesystem allocates its own private area and hangs 37 * it from v_data. If non-null, this area is freed in getnewvnode(). 38 */ 39 LIST_HEAD(buflists, buf); 40 41 /* 42 * Reading or writing any of these items requires holding the appropriate lock. 43 * v_freelist is locked by the global vnode_free_list simple lock. 44 * v_mntvnodes is locked by the global mntvnodes simple lock. 45 * v_flag, v_usecount, v_holdcount and v_writecount are 46 * locked by the v_interlock simple lock. 47 */ 48 struct vnode { 49 u_long v_flag; /* vnode flags (see below) */ 50 short v_usecount; /* reference count of users */ 51 short v_writecount; /* reference count of writers */ 52 long v_holdcnt; /* page & buffer references */ 53 daddr_t v_lastr; /* last read (read-ahead) */ 54 u_long v_id; /* capability identifier */ 55 struct mount *v_mount; /* ptr to vfs we are in */ 56 int (**v_op)(); /* vnode operations vector */ 57 TAILQ_ENTRY(vnode) v_freelist; /* vnode freelist */ 58 LIST_ENTRY(vnode) v_mntvnodes; /* vnodes for mount point */ 59 struct buflists v_cleanblkhd; /* clean blocklist head */ 60 struct buflists v_dirtyblkhd; /* dirty blocklist head */ 61 long v_numoutput; /* num of writes in progress */ 62 enum vtype v_type; /* vnode type */ 63 union { 64 struct mount *vu_mountedhere;/* ptr to mounted vfs (VDIR) */ 65 struct socket *vu_socket; /* unix ipc (VSOCK) */ 66 caddr_t vu_vmdata; /* private data for vm (VREG) */ 67 struct specinfo *vu_specinfo; /* device (VCHR, VBLK) */ 68 struct fifoinfo *vu_fifoinfo; /* fifo (VFIFO) */ 69 } v_un; 70 struct nqlease *v_lease; /* Soft reference to lease */ 71 daddr_t v_lastw; /* last write (write cluster) */ 72 daddr_t v_cstart; /* start block of cluster */ 73 daddr_t v_lasta; /* last allocation */ 74 int v_clen; /* length of current cluster */ 75 int v_ralen; /* Read-ahead length */ 76 daddr_t v_maxra; /* last readahead block */ 77 struct simplelock v_interlock; /* lock on usecount and flag */ 78 struct lock *v_vnlock; /* used for non-locking fs's */ 79 long v_spare[5]; /* round to 128 bytes */ 80 enum vtagtype v_tag; /* type of underlying data */ 81 void *v_data; /* private data for fs */ 82 }; 83 #define v_mountedhere v_un.vu_mountedhere 84 #define v_socket v_un.vu_socket 85 #define v_vmdata v_un.vu_vmdata 86 #define v_specinfo v_un.vu_specinfo 87 #define v_fifoinfo v_un.vu_fifoinfo 88 89 /* 90 * Vnode flags. 91 */ 92 #define VROOT 0x0001 /* root of its file system */ 93 #define VTEXT 0x0002 /* vnode is a pure text prototype */ 94 #define VSYSTEM 0x0004 /* vnode being used by kernel */ 95 #define VISTTY 0x0008 /* vnode represents a tty */ 96 #define VXLOCK 0x0100 /* vnode is locked to change underlying type */ 97 #define VXWANT 0x0200 /* process is waiting for vnode */ 98 #define VBWAIT 0x0400 /* waiting for output to complete */ 99 #define VALIASED 0x0800 /* vnode has an alias */ 100 #define VDIROP 0x1000 /* LFS: vnode is involved in a directory op */ 101 102 /* 103 * Vnode attributes. A field value of VNOVAL represents a field whose value 104 * is unavailable (getattr) or which is not to be changed (setattr). 105 */ 106 struct vattr { 107 enum vtype va_type; /* vnode type (for create) */ 108 u_short va_mode; /* files access mode and type */ 109 short va_nlink; /* number of references to file */ 110 uid_t va_uid; /* owner user id */ 111 gid_t va_gid; /* owner group id */ 112 long va_fsid; /* file system id (dev for now) */ 113 long va_fileid; /* file id */ 114 u_quad_t va_size; /* file size in bytes */ 115 long va_blocksize; /* blocksize preferred for i/o */ 116 struct timespec va_atime; /* time of last access */ 117 struct timespec va_mtime; /* time of last modification */ 118 struct timespec va_ctime; /* time file changed */ 119 u_long va_gen; /* generation number of file */ 120 u_long va_flags; /* flags defined for file */ 121 dev_t va_rdev; /* device the special file represents */ 122 u_quad_t va_bytes; /* bytes of disk space held by file */ 123 u_quad_t va_filerev; /* file modification number */ 124 u_int va_vaflags; /* operations flags, see below */ 125 long va_spare; /* remain quad aligned */ 126 }; 127 128 /* 129 * Flags for va_vaflags. 130 */ 131 #define VA_UTIMES_NULL 0x01 /* utimes argument was NULL */ 132 #define VA_EXCLUSIVE 0x02 /* exclusive create request */ 133 134 /* 135 * Flags for ioflag. 136 */ 137 #define IO_UNIT 0x01 /* do I/O as atomic unit */ 138 #define IO_APPEND 0x02 /* append write to end */ 139 #define IO_SYNC 0x04 /* do I/O synchronously */ 140 #define IO_NODELOCKED 0x08 /* underlying node already locked */ 141 #define IO_NDELAY 0x10 /* FNDELAY flag set in file table */ 142 143 /* 144 * Modes. Some values same as Ixxx entries from inode.h for now. 145 */ 146 #define VSUID 04000 /* set user id on execution */ 147 #define VSGID 02000 /* set group id on execution */ 148 #define VSVTX 01000 /* save swapped text even after use */ 149 #define VREAD 00400 /* read, write, execute permissions */ 150 #define VWRITE 00200 151 #define VEXEC 00100 152 153 /* 154 * Token indicating no attribute value yet assigned. 155 */ 156 #define VNOVAL (-1) 157 158 #ifdef KERNEL 159 /* 160 * Convert between vnode types and inode formats (since POSIX.1 161 * defines mode word of stat structure in terms of inode formats). 162 */ 163 extern enum vtype iftovt_tab[]; 164 extern int vttoif_tab[]; 165 #define IFTOVT(mode) (iftovt_tab[((mode) & S_IFMT) >> 12]) 166 #define VTTOIF(indx) (vttoif_tab[(int)(indx)]) 167 #define MAKEIMODE(indx, mode) (int)(VTTOIF(indx) | (mode)) 168 169 /* 170 * Flags to various vnode functions. 171 */ 172 #define SKIPSYSTEM 0x0001 /* vflush: skip vnodes marked VSYSTEM */ 173 #define FORCECLOSE 0x0002 /* vflush: force file closeure */ 174 #define WRITECLOSE 0x0004 /* vflush: only close writeable files */ 175 #define DOCLOSE 0x0008 /* vclean: close active files */ 176 #define V_SAVE 0x0001 /* vinvalbuf: sync file first */ 177 #define V_SAVEMETA 0x0002 /* vinvalbuf: leave indirect blocks */ 178 #define REVOKEALL 0x0001 /* vop_revoke: revoke all aliases */ 179 180 #ifdef DIAGNOSTIC 181 #define HOLDRELE(vp) holdrele(vp) 182 #define VATTR_NULL(vap) vattr_null(vap) 183 #define VHOLD(vp) vhold(vp) 184 #define VREF(vp) vref(vp) 185 186 void holdrele __P((struct vnode *)); 187 void vattr_null __P((struct vattr *)); 188 void vhold __P((struct vnode *)); 189 void vref __P((struct vnode *)); 190 #else 191 #define VATTR_NULL(vap) (*(vap) = va_null) /* initialize a vattr */ 192 #define HOLDRELE(vp) holdrele(vp) /* decrease buf or page ref */ 193 static __inline holdrele(vp) 194 struct vnode *vp; 195 { 196 simple_lock(&vp->v_interlock); 197 vp->v_holdcnt--; 198 simple_unlock(&vp->v_interlock); 199 } 200 #define VHOLD(vp) vhold(vp) /* increase buf or page ref */ 201 static __inline vhold(vp) 202 struct vnode *vp; 203 { 204 simple_lock(&vp->v_interlock); 205 vp->v_holdcnt++; 206 simple_unlock(&vp->v_interlock); 207 } 208 #define VREF(vp) vref(vp) /* increase reference */ 209 static __inline vref(vp) 210 struct vnode *vp; 211 { 212 simple_lock(&vp->v_interlock); 213 vp->v_usecount++; 214 simple_unlock(&vp->v_interlock); 215 } 216 #endif /* DIAGNOSTIC */ 217 218 #define NULLVP ((struct vnode *)NULL) 219 220 /* 221 * Global vnode data. 222 */ 223 extern struct vnode *rootvnode; /* root (i.e. "/") vnode */ 224 extern int desiredvnodes; /* number of vnodes desired */ 225 extern 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 */ 232 233 #endif /* KERNEL */ 234 235 236 /* 237 * Mods for exensibility. 238 */ 239 240 /* 241 * Flags for vdesc_flags: 242 */ 243 #define VDESC_MAX_VPS 16 244 /* Low order 16 flag bits are reserved for willrele flags for vp arguments. */ 245 #define VDESC_VP0_WILLRELE 0x0001 246 #define VDESC_VP1_WILLRELE 0x0002 247 #define VDESC_VP2_WILLRELE 0x0004 248 #define VDESC_VP3_WILLRELE 0x0008 249 #define VDESC_NOMAP_VPP 0x0100 250 #define VDESC_VPP_WILLRELE 0x0200 251 252 /* 253 * VDESC_NO_OFFSET is used to identify the end of the offset list 254 * and in places where no such field exists. 255 */ 256 #define VDESC_NO_OFFSET -1 257 258 /* 259 * This structure describes the vnode operation taking place. 260 */ 261 struct vnodeop_desc { 262 int vdesc_offset; /* offset in vector--first for speed */ 263 char *vdesc_name; /* a readable name for debugging */ 264 int vdesc_flags; /* VDESC_* flags */ 265 266 /* 267 * These ops are used by bypass routines to map and locate arguments. 268 * Creds and procs are not needed in bypass routines, but sometimes 269 * they are useful to (for example) transport layers. 270 * Nameidata is useful because it has a cred in it. 271 */ 272 int *vdesc_vp_offsets; /* list ended by VDESC_NO_OFFSET */ 273 int vdesc_vpp_offset; /* return vpp location */ 274 int vdesc_cred_offset; /* cred location, if any */ 275 int vdesc_proc_offset; /* proc location, if any */ 276 int vdesc_componentname_offset; /* if any */ 277 /* 278 * Finally, we've got a list of private data (about each operation) 279 * for each transport layer. (Support to manage this list is not 280 * yet part of BSD.) 281 */ 282 caddr_t *vdesc_transports; 283 }; 284 285 #ifdef KERNEL 286 /* 287 * A list of all the operation descs. 288 */ 289 extern struct vnodeop_desc *vnodeop_descs[]; 290 291 /* 292 * Interlock for scanning list of vnodes attached to a mountpoint 293 */ 294 struct simplelock mntvnode_slock; 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 */ 314 struct vnodeopv_entry_desc { 315 struct vnodeop_desc *opve_op; /* which operation this is */ 316 int (*opve_impl)(); /* code implementing this operation */ 317 }; 318 struct 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 */ 327 int vn_default_error __P((void)); 328 329 /* 330 * A generic structure. 331 * This can be used by bypass routines to identify generic arguments. 332 */ 333 struct 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 */ 360 struct file; 361 struct mount; 362 struct nameidata; 363 struct ostat; 364 struct proc; 365 struct stat; 366 struct ucred; 367 struct uio; 368 struct vattr; 369 struct vnode; 370 struct vop_bwrite_args; 371 372 int bdevvp __P((dev_t dev, struct vnode **vpp)); 373 void cvtstat __P((struct stat *st, struct ostat *ost)); 374 int getnewvnode __P((enum vtagtype tag, 375 struct mount *mp, int (**vops)(), struct vnode **vpp)); 376 void insmntque __P((struct vnode *vp, struct mount *mp)); 377 void vattr_null __P((struct vattr *vap)); 378 int vcount __P((struct vnode *vp)); 379 int vflush __P((struct mount *mp, struct vnode *skipvp, int flags)); 380 int vget __P((struct vnode *vp, int lockflag, struct proc *p)); 381 void vgone __P((struct vnode *vp)); 382 int vinvalbuf __P((struct vnode *vp, int save, struct ucred *cred, 383 struct proc *p, int slpflag, int slptimeo)); 384 void vprint __P((char *label, struct vnode *vp)); 385 int vrecycle __P((struct vnode *vp, struct simplelock *inter_lkp, 386 struct proc *p)); 387 int vn_bwrite __P((struct vop_bwrite_args *ap)); 388 int vn_close __P((struct vnode *vp, 389 int flags, struct ucred *cred, struct proc *p)); 390 int vn_closefile __P((struct file *fp, struct proc *p)); 391 int vn_ioctl __P((struct file *fp, u_long com, caddr_t data, 392 struct proc *p)); 393 int vn_lock __P((struct vnode *vp, int flags, struct proc *p)); 394 int vn_open __P((struct nameidata *ndp, int fmode, int cmode)); 395 int vn_rdwr __P((enum uio_rw rw, struct vnode *vp, caddr_t base, 396 int len, off_t offset, enum uio_seg segflg, int ioflg, 397 struct ucred *cred, int *aresid, struct proc *p)); 398 int vn_read __P((struct file *fp, struct uio *uio, struct ucred *cred)); 399 int vn_select __P((struct file *fp, int which, struct proc *p)); 400 int vn_stat __P((struct vnode *vp, struct stat *sb, struct proc *p)); 401 int vn_write __P((struct file *fp, struct uio *uio, struct ucred *cred)); 402 int vop_noislocked __P((struct vop_islocked_args *)); 403 int vop_nolock __P((struct vop_lock_args *)); 404 int vop_nounlock __P((struct vop_unlock_args *)); 405 int vop_revoke __P((struct vop_revoke_args *)); 406 struct vnode * 407 checkalias __P((struct vnode *vp, dev_t nvp_rdev, struct mount *mp)); 408 void vput __P((struct vnode *vp)); 409 void vref __P((struct vnode *vp)); 410 void vrele __P((struct vnode *vp)); 411 #endif /* KERNEL */ 412