1 /* 2 * Copyright (c) 1982, 1986, 1989 Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)vfs_vnops.c 7.42 (Berkeley) 06/25/92 8 */ 9 10 #include "param.h" 11 #include "systm.h" 12 #include "kernel.h" 13 #include "file.h" 14 #include "stat.h" 15 #include "buf.h" 16 #include "proc.h" 17 #include "mount.h" 18 #include "namei.h" 19 #include "vnode.h" 20 #include "ioctl.h" 21 #include "tty.h" 22 #include <vm/vm.h> 23 24 struct fileops vnops = 25 { vn_read, vn_write, vn_ioctl, vn_select, vn_closefile }; 26 27 /* 28 * Common code for vnode open operations. 29 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine. 30 */ 31 vn_open(ndp, fmode, cmode) 32 register struct nameidata *ndp; 33 int fmode, cmode; 34 { 35 USES_VOP_ABORTOP; 36 USES_VOP_ACCESS; 37 USES_VOP_CREATE; 38 USES_VOP_OPEN; 39 USES_VOP_SETATTR; 40 register struct vnode *vp; 41 register struct proc *p = ndp->ni_cnd.cn_proc; 42 register struct ucred *cred = p->p_ucred; 43 struct vattr vat; 44 struct vattr *vap = &vat; 45 int error; 46 47 if (fmode & O_CREAT) { 48 ndp->ni_cnd.cn_nameiop = CREATE; 49 ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF; 50 if ((fmode & O_EXCL) == 0) 51 ndp->ni_cnd.cn_flags |= FOLLOW; 52 if (error = namei(ndp)) 53 return (error); 54 if (ndp->ni_vp == NULL) { 55 VATTR_NULL(vap); 56 vap->va_type = VREG; 57 vap->va_mode = cmode; 58 LEASE_CHECK(ndp->ni_dvp, p, cred, LEASE_WRITE); 59 if (error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp, 60 &ndp->ni_cnd, vap)) 61 return (error); 62 fmode &= ~O_TRUNC; 63 vp = ndp->ni_vp; 64 } else { 65 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); 66 if (ndp->ni_dvp == ndp->ni_vp) 67 vrele(ndp->ni_dvp); 68 else 69 vput(ndp->ni_dvp); 70 ndp->ni_dvp = NULL; 71 vp = ndp->ni_vp; 72 if (fmode & O_EXCL) { 73 error = EEXIST; 74 goto bad; 75 } 76 fmode &= ~O_CREAT; 77 } 78 } else { 79 ndp->ni_cnd.cn_nameiop = LOOKUP; 80 ndp->ni_cnd.cn_flags = FOLLOW | LOCKLEAF; 81 if (error = namei(ndp)) 82 return (error); 83 vp = ndp->ni_vp; 84 } 85 if (vp->v_type == VSOCK) { 86 error = EOPNOTSUPP; 87 goto bad; 88 } 89 if ((fmode & O_CREAT) == 0) { 90 if (fmode & FREAD) { 91 if (error = VOP_ACCESS(vp, VREAD, cred, p)) 92 goto bad; 93 } 94 if (fmode & (FWRITE | O_TRUNC)) { 95 if (vp->v_type == VDIR) { 96 error = EISDIR; 97 goto bad; 98 } 99 if ((error = vn_writechk(vp)) || 100 (error = VOP_ACCESS(vp, VWRITE, cred, p))) 101 goto bad; 102 } 103 } 104 if (fmode & O_TRUNC) { 105 VATTR_NULL(vap); 106 vap->va_size = 0; 107 LEASE_CHECK(vp, p, cred, LEASE_WRITE); 108 if (error = VOP_SETATTR(vp, vap, cred, p)) 109 goto bad; 110 } 111 if (error = VOP_OPEN(vp, fmode, cred, p)) 112 goto bad; 113 if (fmode & FWRITE) 114 vp->v_writecount++; 115 return (0); 116 bad: 117 vput(vp); 118 return (error); 119 } 120 121 /* 122 * Check for write permissions on the specified vnode. 123 * The read-only status of the file system is checked. 124 * Also, prototype text segments cannot be written. 125 */ 126 vn_writechk(vp) 127 register struct vnode *vp; 128 { 129 130 /* 131 * Disallow write attempts on read-only file systems; 132 * unless the file is a socket or a block or character 133 * device resident on the file system. 134 */ 135 if (vp->v_mount->mnt_flag & MNT_RDONLY) { 136 switch (vp->v_type) { 137 case VREG: case VDIR: case VLNK: 138 return (EROFS); 139 } 140 } 141 /* 142 * If there's shared text associated with 143 * the vnode, try to free it up once. If 144 * we fail, we can't allow writing. 145 */ 146 if ((vp->v_flag & VTEXT) && !vnode_pager_uncache(vp)) 147 return (ETXTBSY); 148 return (0); 149 } 150 151 /* 152 * Vnode close call 153 */ 154 vn_close(vp, flags, cred, p) 155 register struct vnode *vp; 156 int flags; 157 struct ucred *cred; 158 struct proc *p; 159 { 160 USES_VOP_CLOSE; 161 int error; 162 163 if (flags & FWRITE) 164 vp->v_writecount--; 165 error = VOP_CLOSE(vp, flags, cred, p); 166 vrele(vp); 167 return (error); 168 } 169 170 /* 171 * Package up an I/O request on a vnode into a uio and do it. 172 */ 173 vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, cred, aresid, p) 174 enum uio_rw rw; 175 struct vnode *vp; 176 caddr_t base; 177 int len; 178 off_t offset; 179 enum uio_seg segflg; 180 int ioflg; 181 struct ucred *cred; 182 int *aresid; 183 struct proc *p; 184 { 185 USES_VOP_LOCK; 186 USES_VOP_READ; 187 USES_VOP_UNLOCK; 188 USES_VOP_WRITE; 189 struct uio auio; 190 struct iovec aiov; 191 int error; 192 193 if ((ioflg & IO_NODELOCKED) == 0) 194 VOP_LOCK(vp); 195 auio.uio_iov = &aiov; 196 auio.uio_iovcnt = 1; 197 aiov.iov_base = base; 198 aiov.iov_len = len; 199 auio.uio_resid = len; 200 auio.uio_offset = offset; 201 auio.uio_segflg = segflg; 202 auio.uio_rw = rw; 203 auio.uio_procp = p; 204 if (rw == UIO_READ) { 205 LEASE_CHECK(vp, p, cred, LEASE_READ); 206 error = VOP_READ(vp, &auio, ioflg, cred); 207 } else { 208 LEASE_CHECK(vp, p, cred, LEASE_WRITE); 209 error = VOP_WRITE(vp, &auio, ioflg, cred); 210 } 211 if (aresid) 212 *aresid = auio.uio_resid; 213 else 214 if (auio.uio_resid && error == 0) 215 error = EIO; 216 if ((ioflg & IO_NODELOCKED) == 0) 217 VOP_UNLOCK(vp); 218 return (error); 219 } 220 221 /* 222 * File table vnode read routine. 223 */ 224 vn_read(fp, uio, cred) 225 struct file *fp; 226 struct uio *uio; 227 struct ucred *cred; 228 { 229 USES_VOP_LOCK; 230 USES_VOP_READ; 231 USES_VOP_UNLOCK; 232 register struct vnode *vp = (struct vnode *)fp->f_data; 233 int count, error; 234 235 VOP_LOCK(vp); 236 uio->uio_offset = fp->f_offset; 237 count = uio->uio_resid; 238 LEASE_CHECK(vp, uio->uio_procp, cred, LEASE_READ); 239 error = VOP_READ(vp, uio, (fp->f_flag & FNONBLOCK) ? IO_NDELAY : 0, 240 cred); 241 fp->f_offset += count - uio->uio_resid; 242 VOP_UNLOCK(vp); 243 return (error); 244 } 245 246 /* 247 * File table vnode write routine. 248 */ 249 vn_write(fp, uio, cred) 250 struct file *fp; 251 struct uio *uio; 252 struct ucred *cred; 253 { 254 USES_VOP_LOCK; 255 USES_VOP_UNLOCK; 256 USES_VOP_WRITE; 257 register struct vnode *vp = (struct vnode *)fp->f_data; 258 int count, error, ioflag = 0; 259 260 if (vp->v_type == VREG && (fp->f_flag & O_APPEND)) 261 ioflag |= IO_APPEND; 262 if (fp->f_flag & FNONBLOCK) 263 ioflag |= IO_NDELAY; 264 VOP_LOCK(vp); 265 uio->uio_offset = fp->f_offset; 266 count = uio->uio_resid; 267 LEASE_CHECK(vp, uio->uio_procp, cred, LEASE_WRITE); 268 error = VOP_WRITE(vp, uio, ioflag, cred); 269 if (ioflag & IO_APPEND) 270 fp->f_offset = uio->uio_offset; 271 else 272 fp->f_offset += count - uio->uio_resid; 273 VOP_UNLOCK(vp); 274 return (error); 275 } 276 277 /* 278 * File table vnode stat routine. 279 */ 280 vn_stat(vp, sb, p) 281 struct vnode *vp; 282 register struct stat *sb; 283 struct proc *p; 284 { 285 USES_VOP_GETATTR; 286 struct vattr vattr; 287 register struct vattr *vap; 288 int error; 289 u_short mode; 290 291 vap = &vattr; 292 error = VOP_GETATTR(vp, vap, p->p_ucred, p); 293 if (error) 294 return (error); 295 /* 296 * Copy from vattr table 297 */ 298 sb->st_dev = vap->va_fsid; 299 sb->st_ino = vap->va_fileid; 300 mode = vap->va_mode; 301 switch (vp->v_type) { 302 case VREG: 303 mode |= S_IFREG; 304 break; 305 case VDIR: 306 mode |= S_IFDIR; 307 break; 308 case VBLK: 309 mode |= S_IFBLK; 310 break; 311 case VCHR: 312 mode |= S_IFCHR; 313 break; 314 case VLNK: 315 mode |= S_IFLNK; 316 break; 317 case VSOCK: 318 mode |= S_IFSOCK; 319 break; 320 case VFIFO: 321 mode |= S_IFIFO; 322 break; 323 default: 324 return (EBADF); 325 }; 326 sb->st_mode = mode; 327 sb->st_nlink = vap->va_nlink; 328 sb->st_uid = vap->va_uid; 329 sb->st_gid = vap->va_gid; 330 sb->st_rdev = vap->va_rdev; 331 sb->st_size = vap->va_size; 332 sb->st_atimespec = vap->va_atime; 333 sb->st_mtimespec= vap->va_mtime; 334 sb->st_ctimespec = vap->va_ctime; 335 sb->st_blksize = vap->va_blocksize; 336 sb->st_flags = vap->va_flags; 337 sb->st_gen = vap->va_gen; 338 sb->st_blocks = vap->va_bytes / S_BLKSIZE; 339 return (0); 340 } 341 342 /* 343 * File table vnode ioctl routine. 344 */ 345 vn_ioctl(fp, com, data, p) 346 struct file *fp; 347 int com; 348 caddr_t data; 349 struct proc *p; 350 { 351 USES_VOP_GETATTR; 352 USES_VOP_IOCTL; 353 register struct vnode *vp = ((struct vnode *)fp->f_data); 354 struct vattr vattr; 355 int error; 356 357 switch (vp->v_type) { 358 359 case VREG: 360 case VDIR: 361 if (com == FIONREAD) { 362 if (error = VOP_GETATTR(vp, &vattr, p->p_ucred, p)) 363 return (error); 364 *(off_t *)data = vattr.va_size - fp->f_offset; 365 return (0); 366 } 367 if (com == FIONBIO || com == FIOASYNC) /* XXX */ 368 return (0); /* XXX */ 369 /* fall into ... */ 370 371 default: 372 return (ENOTTY); 373 374 case VFIFO: 375 case VCHR: 376 case VBLK: 377 error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p); 378 if (error == 0 && com == TIOCSCTTY) { 379 p->p_session->s_ttyvp = vp; 380 VREF(vp); 381 } 382 return (error); 383 } 384 } 385 386 /* 387 * File table vnode select routine. 388 */ 389 vn_select(fp, which, p) 390 struct file *fp; 391 int which; 392 struct proc *p; 393 { 394 USES_VOP_SELECT; 395 396 return (VOP_SELECT(((struct vnode *)fp->f_data), which, fp->f_flag, 397 fp->f_cred, p)); 398 } 399 400 /* 401 * File table vnode close routine. 402 */ 403 vn_closefile(fp, p) 404 struct file *fp; 405 struct proc *p; 406 { 407 408 return (vn_close(((struct vnode *)fp->f_data), fp->f_flag, 409 fp->f_cred, p)); 410 } 411 412 /* 413 * vn_fhtovp() - convert a fh to a vnode ptr (optionally locked) 414 * - look up fsid in mount list (if not found ret error) 415 * - get vp by calling VFS_FHTOVP() macro 416 * - if lockflag lock it with VOP_LOCK() 417 */ 418 vn_fhtovp(fhp, lockflag, vpp) 419 fhandle_t *fhp; 420 int lockflag; 421 struct vnode **vpp; 422 { 423 USES_VOP_UNLOCK; 424 register struct mount *mp; 425 426 if ((mp = getvfs(&fhp->fh_fsid)) == NULL) 427 return (ESTALE); 428 if (VFS_FHTOVP(mp, &fhp->fh_fid, vpp)) 429 return (ESTALE); 430 if (!lockflag) 431 VOP_UNLOCK(*vpp); 432 return (0); 433 } 434