1 /* 2 * Copyright (c) 1989 The Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)vnode.h 7.60 (Berkeley) 07/24/92 8 */ 9 10 #ifndef KERNEL 11 #include <machine/endian.h> 12 #endif 13 14 /* 15 * The vnode is the focus of all file activity in UNIX. There is a 16 * unique vnode allocated for each active file, each current directory, 17 * each mounted-on file, text file, and the root. 18 */ 19 20 /* 21 * Vnode types. VNON means no type. 22 */ 23 enum vtype { VNON, VREG, VDIR, VBLK, VCHR, VLNK, VSOCK, VFIFO, VBAD }; 24 25 /* 26 * Vnode tag types. 27 * These are for the benefit of external programs only (e.g., pstat) 28 * and should NEVER be inspected by the kernel. 29 */ 30 enum vtagtype { VT_NON, VT_UFS, VT_NFS, VT_MFS, VT_LFS }; 31 32 /* 33 * Each underlying filesystem allocates its own private area and hangs 34 * it from v_data. If non-null, this area is free in getnewvnode(). 35 */ 36 struct vnode { 37 u_long v_flag; /* vnode flags (see below) */ 38 short v_usecount; /* reference count of users */ 39 short v_writecount; /* reference count of writers */ 40 long v_holdcnt; /* page & buffer references */ 41 daddr_t v_lastr; /* last read (read-ahead) */ 42 u_long v_id; /* capability identifier */ 43 struct mount *v_mount; /* ptr to vfs we are in */ 44 int (**v_op)(); /* vnode operations vector */ 45 struct vnode *v_freef; /* vnode freelist forward */ 46 struct vnode **v_freeb; /* vnode freelist back */ 47 struct vnode *v_mountf; /* vnode mountlist forward */ 48 struct vnode **v_mountb; /* vnode mountlist back */ 49 struct buf *v_cleanblkhd; /* clean blocklist head */ 50 struct buf *v_dirtyblkhd; /* dirty blocklist head */ 51 long v_numoutput; /* num of writes in progress */ 52 enum vtype v_type; /* vnode type */ 53 union { 54 struct mount *vu_mountedhere;/* ptr to mounted vfs (VDIR) */ 55 struct socket *vu_socket; /* unix ipc (VSOCK) */ 56 caddr_t vu_vmdata; /* private data for vm (VREG) */ 57 struct specinfo *vu_specinfo; /* device (VCHR, VBLK) */ 58 struct fifoinfo *vu_fifoinfo; /* fifo (VFIFO) */ 59 } v_un; 60 struct nqlease *v_lease; /* Soft reference to lease */ 61 long v_spare[13]; /* round to 128 bytes */ 62 enum vtagtype v_tag; /* type of underlying data */ 63 void *v_data; /* private data for fs */ 64 }; 65 #define v_mountedhere v_un.vu_mountedhere 66 #define v_socket v_un.vu_socket 67 #define v_vmdata v_un.vu_vmdata 68 #define v_specinfo v_un.vu_specinfo 69 #define v_fifoinfo v_un.vu_fifoinfo 70 71 /* 72 * Vnode flags. 73 */ 74 #define VROOT 0x0001 /* root of its file system */ 75 #define VTEXT 0x0002 /* vnode is a pure text prototype */ 76 #define VSYSTEM 0x0004 /* vnode being used by kernel */ 77 #define VXLOCK 0x0100 /* vnode is locked to change underlying type */ 78 #define VXWANT 0x0200 /* process is waiting for vnode */ 79 #define VBWAIT 0x0400 /* waiting for output to complete */ 80 #define VALIASED 0x0800 /* vnode has an alias */ 81 #define VDIROP 0x1000 /* LFS: vnode is involved in a directory op */ 82 83 /* 84 * Vnode attributes. A field value of VNOVAL represents a field whose value 85 * is unavailable (getattr) or which is not to be changed (setattr). 86 */ 87 struct vattr { 88 enum vtype va_type; /* vnode type (for create) */ 89 u_short va_mode; /* files access mode and type */ 90 short va_nlink; /* number of references to file */ 91 uid_t va_uid; /* owner user id */ 92 gid_t va_gid; /* owner group id */ 93 long va_fsid; /* file system id (dev for now) */ 94 long va_fileid; /* file id */ 95 u_quad_t va_size; /* file size in bytes */ 96 long va_blocksize; /* blocksize preferred for i/o */ 97 struct timespec va_atime; /* time of last access */ 98 struct timespec va_mtime; /* time of last modification */ 99 struct timespec va_ctime; /* time file changed */ 100 u_long va_gen; /* generation number of file */ 101 u_long va_flags; /* flags defined for file */ 102 dev_t va_rdev; /* device the special file represents */ 103 u_quad_t va_bytes; /* bytes of disk space held by file */ 104 u_quad_t va_filerev; /* file modification number */ 105 }; 106 107 /* 108 * Flags for ioflag. 109 */ 110 #define IO_UNIT 0x01 /* do I/O as atomic unit */ 111 #define IO_APPEND 0x02 /* append write to end */ 112 #define IO_SYNC 0x04 /* do I/O synchronously */ 113 #define IO_NODELOCKED 0x08 /* underlying node already locked */ 114 #define IO_NDELAY 0x10 /* FNDELAY flag set in file table */ 115 116 /* 117 * Modes. Some values same as Ixxx entries from inode.h for now. 118 */ 119 #define VSUID 04000 /* set user id on execution */ 120 #define VSGID 02000 /* set group id on execution */ 121 #define VSVTX 01000 /* save swapped text even after use */ 122 #define VREAD 00400 /* read, write, execute permissions */ 123 #define VWRITE 00200 124 #define VEXEC 00100 125 126 /* 127 * Token indicating no attribute value yet assigned. 128 */ 129 #define VNOVAL (-1) 130 131 #ifdef KERNEL 132 /* 133 * Convert between vnode types and inode formats (since POSIX.1 134 * defines mode word of stat structure in terms of inode formats). 135 */ 136 extern enum vtype iftovt_tab[]; 137 extern int vttoif_tab[]; 138 #define IFTOVT(mode) (iftovt_tab[((mode) & S_IFMT) >> 12]) 139 #define VTTOIF(indx) (vttoif_tab[(int)(indx)]) 140 #define MAKEIMODE(indx, mode) (int)(VTTOIF(indx) | (mode)) 141 142 /* 143 * Flags to various vnode functions. 144 */ 145 #define SKIPSYSTEM 0x0001 /* vflush: skip vnodes marked VSYSTEM */ 146 #define FORCECLOSE 0x0002 /* vflush: force file closeure */ 147 #define DOCLOSE 0x0004 /* vclean: close active files */ 148 149 #ifdef DIAGNOSTIC 150 #define HOLDRELE(vp) holdrele(vp) 151 #define VATTR_NULL(vap) vattr_null(vap) 152 #define VHOLD(vp) vhold(vp) 153 #define VREF(vp) vref(vp) 154 155 void holdrele __P((struct vnode *)); 156 void vattr_null __P((struct vattr *)); 157 void vhold __P((struct vnode *)); 158 void vref __P((struct vnode *)); 159 #else 160 #define HOLDRELE(vp) (vp)->v_holdcnt-- /* decrease buf or page ref */ 161 #define VATTR_NULL(vap) (*(vap) = va_null) /* initialize a vattr */ 162 #define VHOLD(vp) (vp)->v_holdcnt++ /* increase buf or page ref */ 163 #define VREF(vp) (vp)->v_usecount++ /* increase reference */ 164 #endif 165 166 #define NULLVP ((struct vnode *)NULL) 167 168 /* 169 * Global vnode data. 170 */ 171 extern struct vnode *rootdir; /* root (i.e. "/") vnode */ 172 extern int desiredvnodes; /* number of vnodes desired */ 173 extern struct vattr va_null; /* predefined null vattr structure */ 174 175 /* 176 * Macro/function to check for client cache inconsistency w.r.t. leasing. 177 */ 178 #define LEASE_READ 0x1 /* Check lease for readers */ 179 #define LEASE_WRITE 0x2 /* Check lease for modifiers */ 180 181 #ifdef NFS 182 void lease_check __P((struct vnode *vp, struct proc *p, 183 struct ucred *ucred, int flag)); 184 void lease_updatetime __P((int deltat)); 185 #define LEASE_CHECK(vp, p, cred, flag) lease_check((vp), (p), (cred), (flag)) 186 #define LEASE_UPDATETIME(dt) lease_updatetime(dt) 187 #else 188 #define LEASE_CHECK(vp, p, cred, flag) 189 #define LEASE_UPDATETIME(dt) 190 #endif /* NFS */ 191 #endif /* KERNEL */ 192 193 194 /* 195 * Mods for exensibility. 196 */ 197 198 /* 199 * Flags for vdesc_flags: 200 */ 201 #define VDESC_MAX_VPS 16 202 /* Low order 16 flag bits are reserved for willrele flags for vp arguments. */ 203 #define VDESC_VP0_WILLRELE 0x0001 204 #define VDESC_VP1_WILLRELE 0x0002 205 #define VDESC_VP2_WILLRELE 0x0004 206 #define VDESC_VP3_WILLRELE 0x0008 207 #define VDESC_NOMAP_VPP 0x0100 208 #define VDESC_VPP_WILLRELE 0x0200 209 210 /* 211 * VDESC_NO_OFFSET is used to identify the end of the offset list 212 * and in places where no such field exists. 213 */ 214 #define VDESC_NO_OFFSET -1 215 216 /* 217 * This structure describes the vnode operation taking place. 218 */ 219 struct vnodeop_desc { 220 int vdesc_offset; /* offset in vector--first for speed */ 221 char *vdesc_name; /* a readable name for debugging */ 222 int vdesc_flags; /* VDESC_* flags */ 223 224 /* 225 * These ops are used by bypass routines to map and locate arguments. 226 * Creds and procs are not needed in bypass routines, but sometimes 227 * they are useful to (for example) transport layers. 228 * Nameidata is useful because it has a cred in it. 229 */ 230 int *vdesc_vp_offsets; /* list ended by VDESC_NO_OFFSET */ 231 int vdesc_vpp_offset; /* return vpp location */ 232 int vdesc_cred_offset; /* cred location, if any */ 233 int vdesc_proc_offset; /* proc location, if any */ 234 int vdesc_componentname_offset; /* if any */ 235 /* 236 * Finally, we've got a list of private data (about each operation) 237 * for each transport layer. (Support to manage this list is not 238 * yet part of BSD.) 239 */ 240 caddr_t *vdesc_transports; 241 }; 242 243 #ifdef KERNEL 244 /* 245 * A list of all the operation descs. 246 */ 247 extern struct vnodeop_desc *vnodeop_descs[]; 248 249 250 /* 251 * This macro is very helpful in defining those offsets in the vdesc struct. 252 * 253 * This is stolen from X11R4. I ingored all the fancy stuff for 254 * Crays, so if you decide to port this to such a serious machine, 255 * you might want to consult Intrisics.h's XtOffset{,Of,To}. 256 */ 257 #define VOPARG_OFFSET(p_type,field) \ 258 ((int) (((char *) (&(((p_type)NULL)->field))) - ((char *) NULL))) 259 #define VOPARG_OFFSETOF(s_type,field) \ 260 VOPARG_OFFSET(s_type*,field) 261 #define VOPARG_OFFSETTO(S_TYPE,S_OFFSET,STRUCT_P) \ 262 ((S_TYPE)(((char*)(STRUCT_P))+(S_OFFSET))) 263 264 265 /* 266 * This structure is used to configure the new vnodeops vector. 267 */ 268 struct vnodeopv_entry_desc { 269 struct vnodeop_desc *opve_op; /* which operation this is */ 270 int (*opve_impl)(); /* code implementing this operation */ 271 }; 272 struct vnodeopv_desc { 273 /* ptr to the ptr to the vector where op should go */ 274 int (***opv_desc_vector_p)(); 275 struct vnodeopv_entry_desc *opv_desc_ops; /* null terminated list */ 276 }; 277 278 /* 279 * A default routine which just returns an error. 280 */ 281 int vn_default_error __P((void)); 282 283 /* 284 * A generic structure. 285 * This can be used by bypass routines to identify generic arguments. 286 */ 287 struct vop_generic_args { 288 struct vnodeop_desc *a_desc; 289 /* other random data follows, presumably */ 290 }; 291 292 /* 293 * VOCALL calls an op given an ops vector. We break it out because BSD's 294 * vclean changes the ops vector and then wants to call ops with the old 295 * vector. 296 */ 297 #define VOCALL(OPSV,OFF,AP) (( *((OPSV)[(OFF)])) (AP)) 298 299 /* 300 * This call works for vnodes in the kernel. 301 */ 302 #define VCALL(VP,OFF,AP) VOCALL((VP)->v_op,(OFF),(AP)) 303 #define VDESC(OP) (& __CONCAT(OP,_desc)) 304 #define VOFFSET(OP) (VDESC(OP)->vdesc_offset) 305 306 /* 307 * Finally, include the default set of vnode operations. 308 */ 309 #include <vnode_if.h> 310 311 /* 312 * Public vnode manipulation functions. 313 */ 314 struct file; 315 struct mount; 316 struct nameidata; 317 struct proc; 318 struct stat; 319 struct ucred; 320 struct uio; 321 struct vattr; 322 struct vnode; 323 struct vop_bwrite_args; 324 325 int bdevvp __P((dev_t dev, struct vnode **vpp)); 326 int getnewvnode __P((enum vtagtype tag, 327 struct mount *mp, int (**vops)(), struct vnode **vpp)); 328 int vinvalbuf __P((struct vnode *vp, int save, struct ucred *cred, 329 struct proc *p)); 330 void vattr_null __P((struct vattr *vap)); 331 int vcount __P((struct vnode *vp)); 332 int vget __P((struct vnode *vp)); 333 void vgone __P((struct vnode *vp)); 334 void vgoneall __P((struct vnode *vp)); 335 int vn_bwrite __P((struct vop_bwrite_args *ap)); 336 int vn_close __P((struct vnode *vp, 337 int flags, struct ucred *cred, struct proc *p)); 338 int vn_closefile __P((struct file *fp, struct proc *p)); 339 int vn_ioctl __P((struct file *fp, int com, caddr_t data, struct proc *p)); 340 int vn_open __P((struct nameidata *ndp, int fmode, int cmode)); 341 int vn_rdwr __P((enum uio_rw rw, struct vnode *vp, caddr_t base, 342 int len, off_t offset, enum uio_seg segflg, int ioflg, 343 struct ucred *cred, int *aresid, struct proc *p)); 344 int vn_read __P((struct file *fp, struct uio *uio, struct ucred *cred)); 345 int vn_select __P((struct file *fp, int which, struct proc *p)); 346 int vn_stat __P((struct vnode *vp, struct stat *sb, struct proc *p)); 347 int vn_write __P((struct file *fp, struct uio *uio, struct ucred *cred)); 348 struct vnode * 349 checkalias __P((struct vnode *vp, dev_t nvp_rdev, struct mount *mp)); 350 void vput __P((struct vnode *vp)); 351 void vref __P((struct vnode *vp)); 352 void vrele __P((struct vnode *vp)); 353 #endif /* KERNEL */ 354