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 7.51 (Berkeley) 05/15/92 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 unique 16 * vnode allocated for each active file, each current directory, each 17 * 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 inside 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 82 /* 83 * Vnode attributes. A field value of VNOVAL represents a field whose value 84 * is unavailable (getattr) or which is not to be changed (setattr). 85 */ 86 struct vattr { 87 enum vtype va_type; /* vnode type (for create) */ 88 u_short va_mode; /* files access mode and type */ 89 short va_nlink; /* number of references to file */ 90 uid_t va_uid; /* owner user id */ 91 gid_t va_gid; /* owner group id */ 92 long va_fsid; /* file system id (dev for now) */ 93 long va_fileid; /* file id */ 94 u_quad_t va_qsize; /* file size in bytes */ 95 long va_blocksize; /* blocksize preferred for i/o */ 96 struct timeval va_atime; /* time of last access */ 97 struct timeval va_mtime; /* time of last modification */ 98 struct timeval va_ctime; /* time file changed */ 99 u_long va_gen; /* generation number of file */ 100 u_long va_flags; /* flags defined for file */ 101 dev_t va_rdev; /* device the special file represents */ 102 u_quad_t va_qbytes; /* bytes of disk space held by file */ 103 u_quad_t va_filerev; /* file modification number */ 104 }; 105 #ifdef _NOQUAD 106 #define va_size va_qsize.val[_QUAD_LOWWORD] 107 #define va_size_rsv va_qsize.val[_QUAD_HIGHWORD] 108 #define va_bytes va_qbytes.val[_QUAD_LOWWORD] 109 #define va_bytes_rsv va_qbytes.val[_QUAD_HIGHWORD] 110 #else 111 #define va_size va_qsize 112 #define va_bytes va_qbytes 113 #endif 114 115 /* 116 * Operations on vnodes. 117 */ 118 #ifdef __STDC__ 119 struct flock; 120 struct nameidata; 121 struct componentname; 122 #endif 123 124 125 /* 126 * flags for ioflag 127 */ 128 #define IO_UNIT 0x01 /* do I/O as atomic unit */ 129 #define IO_APPEND 0x02 /* append write to end */ 130 #define IO_SYNC 0x04 /* do I/O synchronously */ 131 #define IO_NODELOCKED 0x08 /* underlying node already locked */ 132 #define IO_NDELAY 0x10 /* FNDELAY flag set in file table */ 133 134 /* 135 * Modes. Some values same as Ixxx entries from inode.h for now 136 */ 137 #define VSUID 04000 /* set user id on execution */ 138 #define VSGID 02000 /* set group id on execution */ 139 #define VSVTX 01000 /* save swapped text even after use */ 140 #define VREAD 0400 /* read, write, execute permissions */ 141 #define VWRITE 0200 142 #define VEXEC 0100 143 144 /* 145 * Token indicating no attribute value yet assigned 146 */ 147 #define VNOVAL (-1) 148 149 #ifdef KERNEL 150 /* 151 * Convert between vnode types and inode formats (since POSIX.1 152 * defines mode word of stat structure in terms of inode formats). 153 */ 154 extern enum vtype iftovt_tab[]; 155 extern int vttoif_tab[]; 156 #define IFTOVT(mode) (iftovt_tab[((mode) & IFMT) >> 12]) 157 #define VTTOIF(indx) (vttoif_tab[(int)(indx)]) 158 #define MAKEIMODE(indx, mode) (int)(VTTOIF(indx) | (mode)) 159 160 /* 161 * Flags to various vnode functions. 162 */ 163 #define SKIPSYSTEM 0x0001 /* vflush: skip vnodes marked VSYSTEM */ 164 #define FORCECLOSE 0x0002 /* vflush: force file closeure */ 165 #define DOCLOSE 0x0004 /* vclean: close active files */ 166 167 #ifndef DIAGNOSTIC 168 #define VREF(vp) (vp)->v_usecount++ /* increase reference */ 169 #define VHOLD(vp) (vp)->v_holdcnt++ /* increase buf or page ref */ 170 #define HOLDRELE(vp) (vp)->v_holdcnt-- /* decrease buf or page ref */ 171 #define VATTR_NULL(vap) (*(vap) = va_null) /* initialize a vattr */ 172 #else 173 #define VREF(vp) vref(vp) 174 #define VHOLD(vp) vhold(vp) 175 #define HOLDRELE(vp) holdrele(vp) 176 #define VATTR_NULL(vap) vattr_null(vap) 177 178 void holdrele __P((struct vnode *)); 179 void vattr_null __P((struct vattr *)); 180 void vhold __P((struct vnode *)); 181 void vref __P((struct vnode *)); 182 #endif 183 184 #define NULLVP ((struct vnode *)NULL) 185 186 /* 187 * Global vnode data. 188 */ 189 extern struct vnode *rootdir; /* 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 #ifdef NFS 200 void lease_check __P((struct vnode *vp, struct proc *p, 201 struct ucred *ucred, int flag)); 202 void lease_updatetime __P((int deltat)); 203 #define LEASE_CHECK(vp, p, cred, flag) lease_check((vp), (p), (cred), (flag)) 204 #define LEASE_UPDATETIME(dt) lease_updatetime(dt) 205 #else 206 #define LEASE_CHECK(vp, p, cred, flag) 207 #define LEASE_UPDATETIME(dt) 208 #endif /* NFS */ 209 #endif 210 211 212 /* 213 * Mods for exensibility. 214 */ 215 216 /* 217 * flags for vdesc_flags: 218 */ 219 #define VDESC_MAX_VPS 16 220 /* low order 16 flag bits are reserved for map flags for vp arguments. */ 221 #define VDESC_NOMAP_VPP 0x0100 222 223 /* 224 * VDESC_NO_OFFSET is used to identify the end of the offset list 225 * and in places where no such field exists. 226 */ 227 #define VDESC_NO_OFFSET -1 228 229 /* 230 * This structure describes the vnode operation taking place. 231 */ 232 struct vnodeop_desc { 233 int vdesc_offset; /* offset in vector--first for speed */ 234 char *vdesc_name; /* a readable name for debugging */ 235 int vdesc_flags; /* VDESC_* flags */ 236 237 /* 238 * These ops are used by bypass routines 239 * to map and locate arguments. 240 * Creds and procs are not needed in bypass routines, 241 * but sometimes they are useful to (for example) 242 * transport layers. 243 */ 244 int *vdesc_vp_offsets; /* list ended by VDESC_NO_OFFSET */ 245 int vdesc_vpp_offset; /* return vpp location */ 246 int vdesc_cred_offset; /* cred location, if any */ 247 int vdesc_proc_offset; /* proc location, if any */ 248 /* 249 * Finally, we've got a list of private data 250 * (about each operation) for each transport layer. 251 * (Support to manage this list is not yet part of BSD.) 252 */ 253 caddr_t *vdesc_transports; 254 }; 255 256 /* 257 * A list of all the operation descs. 258 */ 259 extern struct vnodeop_desc *vnodeop_descs[]; 260 261 262 /* 263 * This macro is very helpful in defining those offsets in the vdesc struct. 264 * 265 * This is stolen from X11R4. I ingored all the fancy stuff for 266 * Crays, so if you decide to port this to such a serious machine, 267 * you might want to consult Intrisics.h's XtOffset{,Of,To}. 268 */ 269 #define VOPARG_OFFSET(p_type,field) \ 270 ((int) (((char *) (&(((p_type)NULL)->field))) - ((char *) NULL))) 271 #define VOPARG_OFFSETOF(s_type,field) \ 272 VOPARG_OFFSET(s_type*,field) 273 #define VOPARG_OFFSETTO(S_TYPE,S_OFFSET,STRUCT_P) \ 274 ((S_TYPE)(((char*)(STRUCT_P))+(S_OFFSET))) 275 276 277 /* 278 * This structure is used to configure the new vnodeops vector. 279 */ 280 struct vnodeopv_entry_desc { 281 struct vnodeop_desc *opve_op; /* which operation this is */ 282 int (*opve_impl)(); /* code implementing this operation */ 283 }; 284 struct vnodeopv_desc { 285 int (***opv_desc_vector_p)(); 286 /* ptr to the ptr to the vector where op should go */ 287 struct vnodeopv_entry_desc *opv_desc_ops; /* null terminated list */ 288 }; 289 290 /* 291 * A default routine which just returns an error. 292 */ 293 extern int vn_default_error(); 294 295 /* 296 * A generic structure. 297 * This can be used by bypass routines to identify generic arguments. 298 */ 299 struct vop_generic_args { 300 struct vnodeop_desc *a_desc; 301 /* other random data follows, presumably */ 302 }; 303 304 /* 305 * Standards, standards, standards... 306 */ 307 #ifdef __STDC__ 308 #define CONCAT2(A,B) A##B 309 #else 310 #define CONCAT2(A,B) A/**/B 311 #endif 312 313 /* 314 * VOCALL calls an op given an ops vector. 315 * We break it out because BSD's vclean changes 316 * the ops vector and then wants to call ops 317 * with the old vector. 318 */ 319 #define VOCALL(OPSV,OFF,AP) (( *((OPSV)[(OFF)])) (AP)) 320 /* 321 * This call works for vnodes in the kernel. 322 */ 323 #define VCALL(VP,OFF,AP) VOCALL((VP)->v_op,(OFF),(AP)) 324 #define VDESC(OP) (& CONCAT2(OP,_desc)) 325 #define VOFFSET(OP) (VDESC(OP)->vdesc_offset) 326 327 /* 328 * Finally, include the default set of vnode operations. 329 */ 330 #include <sys/vnode_if.h> 331 332 /* 333 * public vnode manipulation functions 334 */ 335 int vn_open __P((struct nameidata *ndp, int fmode, int cmode)); 336 int vn_close __P((struct vnode *vp, int flags, struct ucred *cred, 337 struct proc *p)); 338 int vn_rdwr __P((enum uio_rw rw, struct vnode *vp, caddr_t base, 339 int len, off_t offset, enum uio_seg segflg, int ioflg, 340 struct ucred *cred, int *aresid, struct proc *p)); 341 int vn_read __P((struct file *fp, struct uio *uio, struct ucred *cred)); 342 int vn_write __P((struct file *fp, struct uio *uio, struct ucred *cred)); 343 int vn_bwrite __P((struct vop_bwrite_args *ap)); 344 int vn_ioctl __P((struct file *fp, int com, caddr_t data, struct proc *p)); 345 int vn_select __P((struct file *fp, int which, struct proc *p)); 346 int vn_closefile __P((struct file *fp, struct proc *p)); 347 int getnewvnode __P((enum vtagtype tag, struct mount *mp, 348 int (**vops)(), struct vnode **vpp)); 349 int bdevvp __P((dev_t dev, struct vnode **vpp)); 350 /* check for special device aliases */ 351 struct vnode *checkalias __P((struct vnode *vp, dev_t nvp_rdev, 352 struct mount *mp)); 353 void vattr_null __P((struct vattr *vap)); 354 int vcount __P((struct vnode *vp)); /* total references to a device */ 355 int vget __P((struct vnode *vp)); /* get first reference to a vnode */ 356 void vref __P((struct vnode *vp)); /* increase reference to a vnode */ 357 void vput __P((struct vnode *vp)); /* unlock and release vnode */ 358 void vrele __P((struct vnode *vp)); /* release vnode */ 359 void vgone __P((struct vnode *vp)); /* completely recycle vnode */ 360 void vgoneall __P((struct vnode *vp));/* recycle vnode and all its aliases */ 361 362 363 364