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 8.10 (Berkeley) 08/10/94 8 */ 9 10 #include <sys/queue.h> 11 12 /* 13 * The vnode is the focus of all file activity in UNIX. There is a 14 * unique vnode allocated for each active file, each current directory, 15 * each mounted-on file, text file, and the root. 16 */ 17 18 /* 19 * Vnode types. VNON means no type. 20 */ 21 enum vtype { VNON, VREG, VDIR, VBLK, VCHR, VLNK, VSOCK, VFIFO, VBAD }; 22 23 /* 24 * Vnode tag types. 25 * These are for the benefit of external programs only (e.g., pstat) 26 * and should NEVER be inspected by the kernel. 27 */ 28 enum vtagtype { 29 VT_NON, VT_UFS, VT_NFS, VT_MFS, VT_PC, VT_LFS, VT_LOFS, VT_FDESC, 30 VT_PORTAL, VT_NULL, VT_UMAP, VT_KERNFS, VT_PROCFS, VT_AFS, VT_ISOFS, 31 VT_UNION 32 }; 33 34 /* 35 * Each underlying filesystem allocates its own private area and hangs 36 * it from v_data. If non-null, this area is freed in getnewvnode(). 37 */ 38 LIST_HEAD(buflists, buf); 39 40 struct vnode { 41 u_long v_flag; /* vnode flags (see below) */ 42 short v_usecount; /* reference count of users */ 43 short v_writecount; /* reference count of writers */ 44 long v_holdcnt; /* page & buffer references */ 45 daddr_t v_lastr; /* last read (read-ahead) */ 46 u_long v_id; /* capability identifier */ 47 struct mount *v_mount; /* ptr to vfs we are in */ 48 int (**v_op)(); /* vnode operations vector */ 49 TAILQ_ENTRY(vnode) v_freelist; /* vnode freelist */ 50 LIST_ENTRY(vnode) v_mntvnodes; /* vnodes for mount point */ 51 struct buflists v_cleanblkhd; /* clean blocklist head */ 52 struct buflists v_dirtyblkhd; /* dirty blocklist head */ 53 long v_numoutput; /* num of writes in progress */ 54 enum vtype v_type; /* vnode type */ 55 union { 56 struct mount *vu_mountedhere;/* ptr to mounted vfs (VDIR) */ 57 struct socket *vu_socket; /* unix ipc (VSOCK) */ 58 caddr_t vu_vmdata; /* private data for vm (VREG) */ 59 struct specinfo *vu_specinfo; /* device (VCHR, VBLK) */ 60 struct fifoinfo *vu_fifoinfo; /* fifo (VFIFO) */ 61 } v_un; 62 struct nqlease *v_lease; /* Soft reference to lease */ 63 daddr_t v_lastw; /* last write (write cluster) */ 64 daddr_t v_cstart; /* start block of cluster */ 65 daddr_t v_lasta; /* last allocation */ 66 int v_clen; /* length of current cluster */ 67 int v_ralen; /* Read-ahead length */ 68 daddr_t v_maxra; /* last readahead block */ 69 long v_spare[7]; /* round to 128 bytes */ 70 enum vtagtype v_tag; /* type of underlying data */ 71 void *v_data; /* private data for fs */ 72 }; 73 #define v_mountedhere v_un.vu_mountedhere 74 #define v_socket v_un.vu_socket 75 #define v_vmdata v_un.vu_vmdata 76 #define v_specinfo v_un.vu_specinfo 77 #define v_fifoinfo v_un.vu_fifoinfo 78 79 /* 80 * Vnode flags. 81 */ 82 #define VROOT 0x0001 /* root of its file system */ 83 #define VTEXT 0x0002 /* vnode is a pure text prototype */ 84 #define VSYSTEM 0x0004 /* vnode being used by kernel */ 85 #define VXLOCK 0x0100 /* vnode is locked to change underlying type */ 86 #define VXWANT 0x0200 /* process is waiting for vnode */ 87 #define VBWAIT 0x0400 /* waiting for output to complete */ 88 #define VALIASED 0x0800 /* vnode has an alias */ 89 #define VDIROP 0x1000 /* LFS: vnode is involved in a directory op */ 90 91 /* 92 * Vnode attributes. A field value of VNOVAL represents a field whose value 93 * is unavailable (getattr) or which is not to be changed (setattr). 94 */ 95 struct vattr { 96 enum vtype va_type; /* vnode type (for create) */ 97 u_short va_mode; /* files access mode and type */ 98 short va_nlink; /* number of references to file */ 99 uid_t va_uid; /* owner user id */ 100 gid_t va_gid; /* owner group id */ 101 long va_fsid; /* file system id (dev for now) */ 102 long va_fileid; /* file id */ 103 u_quad_t va_size; /* file size in bytes */ 104 long va_blocksize; /* blocksize preferred for i/o */ 105 struct timespec va_atime; /* time of last access */ 106 struct timespec va_mtime; /* time of last modification */ 107 struct timespec va_ctime; /* time file changed */ 108 u_long va_gen; /* generation number of file */ 109 u_long va_flags; /* flags defined for file */ 110 dev_t va_rdev; /* device the special file represents */ 111 u_quad_t va_bytes; /* bytes of disk space held by file */ 112 u_quad_t va_filerev; /* file modification number */ 113 u_int va_vaflags; /* operations flags, see below */ 114 long va_spare; /* remain quad aligned */ 115 }; 116 117 /* 118 * Flags for va_cflags. 119 */ 120 #define VA_UTIMES_NULL 0x01 /* utimes argument was NULL */ 121 122 /* 123 * Flags for ioflag. 124 */ 125 #define IO_UNIT 0x01 /* do I/O as atomic unit */ 126 #define IO_APPEND 0x02 /* append write to end */ 127 #define IO_SYNC 0x04 /* do I/O synchronously */ 128 #define IO_NODELOCKED 0x08 /* underlying node already locked */ 129 #define IO_NDELAY 0x10 /* FNDELAY flag set in file table */ 130 131 /* 132 * Modes. Some values same as Ixxx entries from inode.h for now. 133 */ 134 #define VSUID 04000 /* set user id on execution */ 135 #define VSGID 02000 /* set group id on execution */ 136 #define VSVTX 01000 /* save swapped text even after use */ 137 #define VREAD 00400 /* read, write, execute permissions */ 138 #define VWRITE 00200 139 #define VEXEC 00100 140 141 /* 142 * Token indicating no attribute value yet assigned. 143 */ 144 #define VNOVAL (-1) 145 146 #ifdef KERNEL 147 /* 148 * Convert between vnode types and inode formats (since POSIX.1 149 * defines mode word of stat structure in terms of inode formats). 150 */ 151 extern enum vtype iftovt_tab[]; 152 extern int vttoif_tab[]; 153 #define IFTOVT(mode) (iftovt_tab[((mode) & S_IFMT) >> 12]) 154 #define VTTOIF(indx) (vttoif_tab[(int)(indx)]) 155 #define MAKEIMODE(indx, mode) (int)(VTTOIF(indx) | (mode)) 156 157 /* 158 * Flags to various vnode functions. 159 */ 160 #define SKIPSYSTEM 0x0001 /* vflush: skip vnodes marked VSYSTEM */ 161 #define FORCECLOSE 0x0002 /* vflush: force file closeure */ 162 #define WRITECLOSE 0x0004 /* vflush: only close writeable files */ 163 #define DOCLOSE 0x0008 /* vclean: close active files */ 164 #define V_SAVE 0x0001 /* vinvalbuf: sync file first */ 165 #define V_SAVEMETA 0x0002 /* vinvalbuf: leave indirect blocks */ 166 167 #ifdef DIAGNOSTIC 168 #define HOLDRELE(vp) holdrele(vp) 169 #define VATTR_NULL(vap) vattr_null(vap) 170 #define VHOLD(vp) vhold(vp) 171 #define VREF(vp) vref(vp) 172 173 void holdrele __P((struct vnode *)); 174 void vattr_null __P((struct vattr *)); 175 void vhold __P((struct vnode *)); 176 void vref __P((struct vnode *)); 177 #else 178 #define HOLDRELE(vp) (vp)->v_holdcnt-- /* decrease buf or page ref */ 179 #define VATTR_NULL(vap) (*(vap) = va_null) /* initialize a vattr */ 180 #define VHOLD(vp) (vp)->v_holdcnt++ /* increase buf or page ref */ 181 #define VREF(vp) (vp)->v_usecount++ /* increase reference */ 182 #endif 183 184 #define NULLVP ((struct vnode *)NULL) 185 186 /* 187 * Global vnode data. 188 */ 189 extern struct vnode *rootvnode; /* root (i.e. "/") vnode */ 190 extern int desiredvnodes; /* number of vnodes desired */ 191 extern struct vattr va_null; /* predefined null vattr structure */ 192 193 /* 194 * Macro/function to check for client cache inconsistency w.r.t. leasing. 195 */ 196 #define LEASE_READ 0x1 /* Check lease for readers */ 197 #define LEASE_WRITE 0x2 /* Check lease for modifiers */ 198 199 #endif /* KERNEL */ 200 201 202 /* 203 * Mods for exensibility. 204 */ 205 206 /* 207 * Flags for vdesc_flags: 208 */ 209 #define VDESC_MAX_VPS 16 210 /* Low order 16 flag bits are reserved for willrele flags for vp arguments. */ 211 #define VDESC_VP0_WILLRELE 0x0001 212 #define VDESC_VP1_WILLRELE 0x0002 213 #define VDESC_VP2_WILLRELE 0x0004 214 #define VDESC_VP3_WILLRELE 0x0008 215 #define VDESC_NOMAP_VPP 0x0100 216 #define VDESC_VPP_WILLRELE 0x0200 217 218 /* 219 * VDESC_NO_OFFSET is used to identify the end of the offset list 220 * and in places where no such field exists. 221 */ 222 #define VDESC_NO_OFFSET -1 223 224 /* 225 * This structure describes the vnode operation taking place. 226 */ 227 struct vnodeop_desc { 228 int vdesc_offset; /* offset in vector--first for speed */ 229 char *vdesc_name; /* a readable name for debugging */ 230 int vdesc_flags; /* VDESC_* flags */ 231 232 /* 233 * These ops are used by bypass routines to map and locate arguments. 234 * Creds and procs are not needed in bypass routines, but sometimes 235 * they are useful to (for example) transport layers. 236 * Nameidata is useful because it has a cred in it. 237 */ 238 int *vdesc_vp_offsets; /* list ended by VDESC_NO_OFFSET */ 239 int vdesc_vpp_offset; /* return vpp location */ 240 int vdesc_cred_offset; /* cred location, if any */ 241 int vdesc_proc_offset; /* proc location, if any */ 242 int vdesc_componentname_offset; /* if any */ 243 /* 244 * Finally, we've got a list of private data (about each operation) 245 * for each transport layer. (Support to manage this list is not 246 * yet part of BSD.) 247 */ 248 caddr_t *vdesc_transports; 249 }; 250 251 #ifdef KERNEL 252 /* 253 * A list of all the operation descs. 254 */ 255 extern struct vnodeop_desc *vnodeop_descs[]; 256 257 258 /* 259 * This macro is very helpful in defining those offsets in the vdesc struct. 260 * 261 * This is stolen from X11R4. I ingored all the fancy stuff for 262 * Crays, so if you decide to port this to such a serious machine, 263 * you might want to consult Intrisics.h's XtOffset{,Of,To}. 264 */ 265 #define VOPARG_OFFSET(p_type,field) \ 266 ((int) (((char *) (&(((p_type)NULL)->field))) - ((char *) NULL))) 267 #define VOPARG_OFFSETOF(s_type,field) \ 268 VOPARG_OFFSET(s_type*,field) 269 #define VOPARG_OFFSETTO(S_TYPE,S_OFFSET,STRUCT_P) \ 270 ((S_TYPE)(((char*)(STRUCT_P))+(S_OFFSET))) 271 272 273 /* 274 * This structure is used to configure the new vnodeops vector. 275 */ 276 struct vnodeopv_entry_desc { 277 struct vnodeop_desc *opve_op; /* which operation this is */ 278 int (*opve_impl)(); /* code implementing this operation */ 279 }; 280 struct vnodeopv_desc { 281 /* ptr to the ptr to the vector where op should go */ 282 int (***opv_desc_vector_p)(); 283 struct vnodeopv_entry_desc *opv_desc_ops; /* null terminated list */ 284 }; 285 286 /* 287 * A default routine which just returns an error. 288 */ 289 int vn_default_error __P((void)); 290 291 /* 292 * A generic structure. 293 * This can be used by bypass routines to identify generic arguments. 294 */ 295 struct vop_generic_args { 296 struct vnodeop_desc *a_desc; 297 /* other random data follows, presumably */ 298 }; 299 300 /* 301 * VOCALL calls an op given an ops vector. We break it out because BSD's 302 * vclean changes the ops vector and then wants to call ops with the old 303 * vector. 304 */ 305 #define VOCALL(OPSV,OFF,AP) (( *((OPSV)[(OFF)])) (AP)) 306 307 /* 308 * This call works for vnodes in the kernel. 309 */ 310 #define VCALL(VP,OFF,AP) VOCALL((VP)->v_op,(OFF),(AP)) 311 #define VDESC(OP) (& __CONCAT(OP,_desc)) 312 #define VOFFSET(OP) (VDESC(OP)->vdesc_offset) 313 314 /* 315 * Finally, include the default set of vnode operations. 316 */ 317 #include <vnode_if.h> 318 319 /* 320 * Public vnode manipulation functions. 321 */ 322 struct file; 323 struct mount; 324 struct nameidata; 325 struct proc; 326 struct stat; 327 struct ucred; 328 struct uio; 329 struct vattr; 330 struct vnode; 331 struct vop_bwrite_args; 332 333 int bdevvp __P((dev_t dev, struct vnode **vpp)); 334 int getnewvnode __P((enum vtagtype tag, 335 struct mount *mp, int (**vops)(), struct vnode **vpp)); 336 int vinvalbuf __P((struct vnode *vp, int save, struct ucred *cred, 337 struct proc *p, int slpflag, int slptimeo)); 338 void vattr_null __P((struct vattr *vap)); 339 int vcount __P((struct vnode *vp)); 340 int vget __P((struct vnode *vp, int lockflag)); 341 void vgone __P((struct vnode *vp)); 342 void vgoneall __P((struct vnode *vp)); 343 int vn_bwrite __P((struct vop_bwrite_args *ap)); 344 int vn_close __P((struct vnode *vp, 345 int flags, struct ucred *cred, struct proc *p)); 346 int vn_closefile __P((struct file *fp, struct proc *p)); 347 int vn_ioctl __P((struct file *fp, int com, caddr_t data, struct proc *p)); 348 int vn_open __P((struct nameidata *ndp, int fmode, int cmode)); 349 int vn_rdwr __P((enum uio_rw rw, struct vnode *vp, caddr_t base, 350 int len, off_t offset, enum uio_seg segflg, int ioflg, 351 struct ucred *cred, int *aresid, struct proc *p)); 352 int vn_read __P((struct file *fp, struct uio *uio, struct ucred *cred)); 353 int vn_select __P((struct file *fp, int which, struct proc *p)); 354 int vn_stat __P((struct vnode *vp, struct stat *sb, struct proc *p)); 355 int vn_write __P((struct file *fp, struct uio *uio, struct ucred *cred)); 356 struct vnode * 357 checkalias __P((struct vnode *vp, dev_t nvp_rdev, struct mount *mp)); 358 void vput __P((struct vnode *vp)); 359 void vref __P((struct vnode *vp)); 360 void vrele __P((struct vnode *vp)); 361 #endif /* KERNEL */ 362