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 8.16 (Berkeley) 05/14/95 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 long v_spare[6]; /* round to 128 bytes */ 79 enum vtagtype v_tag; /* type of underlying data */ 80 void *v_data; /* private data for fs */ 81 }; 82 #define v_mountedhere v_un.vu_mountedhere 83 #define v_socket v_un.vu_socket 84 #define v_vmdata v_un.vu_vmdata 85 #define v_specinfo v_un.vu_specinfo 86 #define v_fifoinfo v_un.vu_fifoinfo 87 88 /* 89 * Vnode flags. 90 */ 91 #define VROOT 0x0001 /* root of its file system */ 92 #define VTEXT 0x0002 /* vnode is a pure text prototype */ 93 #define VSYSTEM 0x0004 /* vnode being used by kernel */ 94 #define VISTTY 0x0008 /* vnode represents a tty */ 95 #define VXLOCK 0x0100 /* vnode is locked to change underlying type */ 96 #define VXWANT 0x0200 /* process is waiting for vnode */ 97 #define VBWAIT 0x0400 /* waiting for output to complete */ 98 #define VALIASED 0x0800 /* vnode has an alias */ 99 #define VDIROP 0x1000 /* LFS: vnode is involved in a directory op */ 100 101 /* 102 * Vnode attributes. A field value of VNOVAL represents a field whose value 103 * is unavailable (getattr) or which is not to be changed (setattr). 104 */ 105 struct vattr { 106 enum vtype va_type; /* vnode type (for create) */ 107 u_short va_mode; /* files access mode and type */ 108 short va_nlink; /* number of references to file */ 109 uid_t va_uid; /* owner user id */ 110 gid_t va_gid; /* owner group id */ 111 long va_fsid; /* file system id (dev for now) */ 112 long va_fileid; /* file id */ 113 u_quad_t va_size; /* file size in bytes */ 114 long va_blocksize; /* blocksize preferred for i/o */ 115 struct timespec va_atime; /* time of last access */ 116 struct timespec va_mtime; /* time of last modification */ 117 struct timespec va_ctime; /* time file changed */ 118 u_long va_gen; /* generation number of file */ 119 u_long va_flags; /* flags defined for file */ 120 dev_t va_rdev; /* device the special file represents */ 121 u_quad_t va_bytes; /* bytes of disk space held by file */ 122 u_quad_t va_filerev; /* file modification number */ 123 u_int va_vaflags; /* operations flags, see below */ 124 long va_spare; /* remain quad aligned */ 125 }; 126 127 /* 128 * Flags for va_vaflags. 129 */ 130 #define VA_UTIMES_NULL 0x01 /* utimes argument was NULL */ 131 #define VA_EXCLUSIVE 0x02 /* exclusive create request */ 132 133 /* 134 * Flags for ioflag. 135 */ 136 #define IO_UNIT 0x01 /* do I/O as atomic unit */ 137 #define IO_APPEND 0x02 /* append write to end */ 138 #define IO_SYNC 0x04 /* do I/O synchronously */ 139 #define IO_NODELOCKED 0x08 /* underlying node already locked */ 140 #define IO_NDELAY 0x10 /* FNDELAY flag set in file table */ 141 142 /* 143 * Modes. Some values same as Ixxx entries from inode.h for now. 144 */ 145 #define VSUID 04000 /* set user id on execution */ 146 #define VSGID 02000 /* set group id on execution */ 147 #define VSVTX 01000 /* save swapped text even after use */ 148 #define VREAD 00400 /* read, write, execute permissions */ 149 #define VWRITE 00200 150 #define VEXEC 00100 151 152 /* 153 * Token indicating no attribute value yet assigned. 154 */ 155 #define VNOVAL (-1) 156 157 #ifdef KERNEL 158 /* 159 * Convert between vnode types and inode formats (since POSIX.1 160 * defines mode word of stat structure in terms of inode formats). 161 */ 162 extern enum vtype iftovt_tab[]; 163 extern int vttoif_tab[]; 164 #define IFTOVT(mode) (iftovt_tab[((mode) & S_IFMT) >> 12]) 165 #define VTTOIF(indx) (vttoif_tab[(int)(indx)]) 166 #define MAKEIMODE(indx, mode) (int)(VTTOIF(indx) | (mode)) 167 168 /* 169 * Flags to various vnode functions. 170 */ 171 #define SKIPSYSTEM 0x0001 /* vflush: skip vnodes marked VSYSTEM */ 172 #define FORCECLOSE 0x0002 /* vflush: force file closeure */ 173 #define WRITECLOSE 0x0004 /* vflush: only close writeable files */ 174 #define DOCLOSE 0x0008 /* vclean: close active files */ 175 #define V_SAVE 0x0001 /* vinvalbuf: sync file first */ 176 #define V_SAVEMETA 0x0002 /* vinvalbuf: leave indirect blocks */ 177 #define REVOKEALL 0x0001 /* vop_revoke: revoke all aliases */ 178 179 #ifdef DIAGNOSTIC 180 #define HOLDRELE(vp) holdrele(vp) 181 #define VATTR_NULL(vap) vattr_null(vap) 182 #define VHOLD(vp) vhold(vp) 183 #define VREF(vp) vref(vp) 184 185 void holdrele __P((struct vnode *)); 186 void vattr_null __P((struct vattr *)); 187 void vhold __P((struct vnode *)); 188 void vref __P((struct vnode *)); 189 #else 190 #define VATTR_NULL(vap) (*(vap) = va_null) /* initialize a vattr */ 191 #define HOLDRELE(vp) holdrele(vp) /* decrease buf or page ref */ 192 static __inline holdrele(vp) 193 struct vnode *vp; 194 { 195 simple_lock(&vp->v_interlock); 196 vp->v_holdcnt--; 197 simple_unlock(&vp->v_interlock); 198 } 199 #define VHOLD(vp) vhold(vp) /* increase buf or page ref */ 200 static __inline vhold(vp) 201 struct vnode *vp; 202 { 203 simple_lock(&vp->v_interlock); 204 vp->v_holdcnt++; 205 simple_unlock(&vp->v_interlock); 206 } 207 #define VREF(vp) vref(vp) /* increase reference */ 208 static __inline vref(vp) 209 struct vnode *vp; 210 { 211 simple_lock(&vp->v_interlock); 212 vp->v_usecount++; 213 simple_unlock(&vp->v_interlock); 214 } 215 #endif /* DIAGNOSTIC */ 216 217 #define NULLVP ((struct vnode *)NULL) 218 219 /* 220 * Global vnode data. 221 */ 222 extern struct vnode *rootvnode; /* root (i.e. "/") vnode */ 223 extern int desiredvnodes; /* number of vnodes desired */ 224 extern struct vattr va_null; /* predefined null vattr structure */ 225 226 /* 227 * Macro/function to check for client cache inconsistency w.r.t. leasing. 228 */ 229 #define LEASE_READ 0x1 /* Check lease for readers */ 230 #define LEASE_WRITE 0x2 /* Check lease for modifiers */ 231 232 #endif /* KERNEL */ 233 234 235 /* 236 * Mods for exensibility. 237 */ 238 239 /* 240 * Flags for vdesc_flags: 241 */ 242 #define VDESC_MAX_VPS 16 243 /* Low order 16 flag bits are reserved for willrele flags for vp arguments. */ 244 #define VDESC_VP0_WILLRELE 0x0001 245 #define VDESC_VP1_WILLRELE 0x0002 246 #define VDESC_VP2_WILLRELE 0x0004 247 #define VDESC_VP3_WILLRELE 0x0008 248 #define VDESC_NOMAP_VPP 0x0100 249 #define VDESC_VPP_WILLRELE 0x0200 250 251 /* 252 * VDESC_NO_OFFSET is used to identify the end of the offset list 253 * and in places where no such field exists. 254 */ 255 #define VDESC_NO_OFFSET -1 256 257 /* 258 * This structure describes the vnode operation taking place. 259 */ 260 struct vnodeop_desc { 261 int vdesc_offset; /* offset in vector--first for speed */ 262 char *vdesc_name; /* a readable name for debugging */ 263 int vdesc_flags; /* VDESC_* flags */ 264 265 /* 266 * These ops are used by bypass routines to map and locate arguments. 267 * Creds and procs are not needed in bypass routines, but sometimes 268 * they are useful to (for example) transport layers. 269 * Nameidata is useful because it has a cred in it. 270 */ 271 int *vdesc_vp_offsets; /* list ended by VDESC_NO_OFFSET */ 272 int vdesc_vpp_offset; /* return vpp location */ 273 int vdesc_cred_offset; /* cred location, if any */ 274 int vdesc_proc_offset; /* proc location, if any */ 275 int vdesc_componentname_offset; /* if any */ 276 /* 277 * Finally, we've got a list of private data (about each operation) 278 * for each transport layer. (Support to manage this list is not 279 * yet part of BSD.) 280 */ 281 caddr_t *vdesc_transports; 282 }; 283 284 #ifdef KERNEL 285 /* 286 * A list of all the operation descs. 287 */ 288 extern struct vnodeop_desc *vnodeop_descs[]; 289 290 /* 291 * Interlock for scanning list of vnodes attached to a mountpoint 292 */ 293 struct simplelock mntvnode_slock; 294 295 /* 296 * This macro is very helpful in defining those offsets in the vdesc struct. 297 * 298 * This is stolen from X11R4. I ingored all the fancy stuff for 299 * Crays, so if you decide to port this to such a serious machine, 300 * you might want to consult Intrisics.h's XtOffset{,Of,To}. 301 */ 302 #define VOPARG_OFFSET(p_type,field) \ 303 ((int) (((char *) (&(((p_type)NULL)->field))) - ((char *) NULL))) 304 #define VOPARG_OFFSETOF(s_type,field) \ 305 VOPARG_OFFSET(s_type*,field) 306 #define VOPARG_OFFSETTO(S_TYPE,S_OFFSET,STRUCT_P) \ 307 ((S_TYPE)(((char*)(STRUCT_P))+(S_OFFSET))) 308 309 310 /* 311 * This structure is used to configure the new vnodeops vector. 312 */ 313 struct vnodeopv_entry_desc { 314 struct vnodeop_desc *opve_op; /* which operation this is */ 315 int (*opve_impl)(); /* code implementing this operation */ 316 }; 317 struct vnodeopv_desc { 318 /* ptr to the ptr to the vector where op should go */ 319 int (***opv_desc_vector_p)(); 320 struct vnodeopv_entry_desc *opv_desc_ops; /* null terminated list */ 321 }; 322 323 /* 324 * A default routine which just returns an error. 325 */ 326 int vn_default_error __P((void)); 327 328 /* 329 * A generic structure. 330 * This can be used by bypass routines to identify generic arguments. 331 */ 332 struct vop_generic_args { 333 struct vnodeop_desc *a_desc; 334 /* other random data follows, presumably */ 335 }; 336 337 /* 338 * VOCALL calls an op given an ops vector. We break it out because BSD's 339 * vclean changes the ops vector and then wants to call ops with the old 340 * vector. 341 */ 342 #define VOCALL(OPSV,OFF,AP) (( *((OPSV)[(OFF)])) (AP)) 343 344 /* 345 * This call works for vnodes in the kernel. 346 */ 347 #define VCALL(VP,OFF,AP) VOCALL((VP)->v_op,(OFF),(AP)) 348 #define VDESC(OP) (& __CONCAT(OP,_desc)) 349 #define VOFFSET(OP) (VDESC(OP)->vdesc_offset) 350 351 /* 352 * Finally, include the default set of vnode operations. 353 */ 354 #include <vnode_if.h> 355 356 /* 357 * Public vnode manipulation functions. 358 */ 359 struct file; 360 struct mount; 361 struct nameidata; 362 struct ostat; 363 struct proc; 364 struct stat; 365 struct ucred; 366 struct uio; 367 struct vattr; 368 struct vnode; 369 struct vop_bwrite_args; 370 371 int bdevvp __P((dev_t dev, struct vnode **vpp)); 372 void cvtstat __P((struct stat *st, struct ostat *ost)); 373 int getnewvnode __P((enum vtagtype tag, 374 struct mount *mp, int (**vops)(), struct vnode **vpp)); 375 void insmntque __P((struct vnode *vp, struct mount *mp)); 376 void vattr_null __P((struct vattr *vap)); 377 int vcount __P((struct vnode *vp)); 378 int vflush __P((struct mount *mp, struct vnode *skipvp, int flags)); 379 int vget __P((struct vnode *vp, int lockflag, struct proc *p)); 380 void vgone __P((struct vnode *vp)); 381 int vinvalbuf __P((struct vnode *vp, int save, struct ucred *cred, 382 struct proc *p, int slpflag, int slptimeo)); 383 void vprint __P((char *label, struct vnode *vp)); 384 int vrecycle __P((struct vnode *vp, struct simplelock *inter_lkp, 385 struct proc *p)); 386 int vn_bwrite __P((struct vop_bwrite_args *ap)); 387 int vn_close __P((struct vnode *vp, 388 int flags, struct ucred *cred, struct proc *p)); 389 int vn_closefile __P((struct file *fp, struct proc *p)); 390 int vn_ioctl __P((struct file *fp, u_long com, caddr_t data, 391 struct proc *p)); 392 int vn_lock __P((struct vnode *vp, int flags, struct proc *p)); 393 int vn_open __P((struct nameidata *ndp, int fmode, int cmode)); 394 int 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)); 397 int vn_read __P((struct file *fp, struct uio *uio, struct ucred *cred)); 398 int vn_select __P((struct file *fp, int which, struct proc *p)); 399 int vn_stat __P((struct vnode *vp, struct stat *sb, struct proc *p)); 400 int vn_write __P((struct file *fp, struct uio *uio, struct ucred *cred)); 401 int vop_noislocked __P((struct vop_islocked_args *)); 402 int vop_nolock __P((struct vop_lock_args *)); 403 int vop_nounlock __P((struct vop_unlock_args *)); 404 int vop_revoke __P((struct vop_revoke_args *)); 405 struct vnode * 406 checkalias __P((struct vnode *vp, dev_t nvp_rdev, struct mount *mp)); 407 void vput __P((struct vnode *vp)); 408 void vref __P((struct vnode *vp)); 409 void vrele __P((struct vnode *vp)); 410 #endif /* KERNEL */ 411