1 /* 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)vfs_vnops.c 8.2 (Berkeley) 1/21/94 39 */ 40 41 #include <sys/param.h> 42 #include <sys/systm.h> 43 #include <sys/kernel.h> 44 #include <sys/file.h> 45 #include <sys/stat.h> 46 #include <sys/buf.h> 47 #include <sys/proc.h> 48 #include <sys/mount.h> 49 #include <sys/namei.h> 50 #include <sys/vnode.h> 51 #include <sys/ioctl.h> 52 #include <sys/tty.h> 53 54 #include <vm/vm.h> 55 56 struct fileops vnops = 57 { vn_read, vn_write, vn_ioctl, vn_select, vn_closefile }; 58 59 /* 60 * Common code for vnode open operations. 61 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine. 62 */ 63 int 64 vn_open(ndp, fmode, cmode) 65 register struct nameidata *ndp; 66 int fmode, cmode; 67 { 68 register struct vnode *vp; 69 register struct proc *p = ndp->ni_cnd.cn_proc; 70 register struct ucred *cred = p->p_ucred; 71 struct vattr vat; 72 struct vattr *vap = &vat; 73 int error; 74 75 if (fmode & O_CREAT) { 76 ndp->ni_cnd.cn_nameiop = CREATE; 77 ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF; 78 if ((fmode & O_EXCL) == 0) 79 ndp->ni_cnd.cn_flags |= FOLLOW; 80 if (error = namei(ndp)) 81 return (error); 82 if (ndp->ni_vp == NULL) { 83 VATTR_NULL(vap); 84 vap->va_type = VREG; 85 vap->va_mode = cmode; 86 LEASE_CHECK(ndp->ni_dvp, p, cred, LEASE_WRITE); 87 if (error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp, 88 &ndp->ni_cnd, vap)) 89 return (error); 90 fmode &= ~O_TRUNC; 91 vp = ndp->ni_vp; 92 } else { 93 VOP_ABORTOP(ndp->ni_dvp, &ndp->ni_cnd); 94 if (ndp->ni_dvp == ndp->ni_vp) 95 vrele(ndp->ni_dvp); 96 else 97 vput(ndp->ni_dvp); 98 ndp->ni_dvp = NULL; 99 vp = ndp->ni_vp; 100 if (fmode & O_EXCL) { 101 error = EEXIST; 102 goto bad; 103 } 104 fmode &= ~O_CREAT; 105 } 106 } else { 107 ndp->ni_cnd.cn_nameiop = LOOKUP; 108 ndp->ni_cnd.cn_flags = FOLLOW | LOCKLEAF; 109 if (error = namei(ndp)) 110 return (error); 111 vp = ndp->ni_vp; 112 } 113 if (vp->v_type == VSOCK) { 114 error = EOPNOTSUPP; 115 goto bad; 116 } 117 if ((fmode & O_CREAT) == 0) { 118 if (fmode & FREAD) { 119 if (error = VOP_ACCESS(vp, VREAD, cred, p)) 120 goto bad; 121 } 122 if (fmode & (FWRITE | O_TRUNC)) { 123 if (vp->v_type == VDIR) { 124 error = EISDIR; 125 goto bad; 126 } 127 if ((error = vn_writechk(vp)) || 128 (error = VOP_ACCESS(vp, VWRITE, cred, p))) 129 goto bad; 130 } 131 } 132 if (fmode & O_TRUNC) { 133 VOP_UNLOCK(vp); /* XXX */ 134 LEASE_CHECK(vp, p, cred, LEASE_WRITE); 135 VOP_LOCK(vp); /* XXX */ 136 VATTR_NULL(vap); 137 vap->va_size = 0; 138 if (error = VOP_SETATTR(vp, vap, cred, p)) 139 goto bad; 140 } 141 if (error = VOP_OPEN(vp, fmode, cred, p)) 142 goto bad; 143 if (fmode & FWRITE) 144 vp->v_writecount++; 145 return (0); 146 bad: 147 vput(vp); 148 return (error); 149 } 150 151 /* 152 * Check for write permissions on the specified vnode. 153 * The read-only status of the file system is checked. 154 * Also, prototype text segments cannot be written. 155 */ 156 int 157 vn_writechk(vp) 158 register struct vnode *vp; 159 { 160 161 /* 162 * Disallow write attempts on read-only file systems; 163 * unless the file is a socket or a block or character 164 * device resident on the file system. 165 */ 166 if (vp->v_mount->mnt_flag & MNT_RDONLY) { 167 switch (vp->v_type) { 168 case VREG: case VDIR: case VLNK: 169 return (EROFS); 170 } 171 } 172 /* 173 * If there's shared text associated with 174 * the vnode, try to free it up once. If 175 * we fail, we can't allow writing. 176 */ 177 if ((vp->v_flag & VTEXT) && !vnode_pager_uncache(vp)) 178 return (ETXTBSY); 179 return (0); 180 } 181 182 /* 183 * Vnode close call 184 */ 185 int 186 vn_close(vp, flags, cred, p) 187 register struct vnode *vp; 188 int flags; 189 struct ucred *cred; 190 struct proc *p; 191 { 192 int error; 193 194 if (flags & FWRITE) 195 vp->v_writecount--; 196 error = VOP_CLOSE(vp, flags, cred, p); 197 vrele(vp); 198 return (error); 199 } 200 201 /* 202 * Package up an I/O request on a vnode into a uio and do it. 203 */ 204 int 205 vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, cred, aresid, p) 206 enum uio_rw rw; 207 struct vnode *vp; 208 caddr_t base; 209 int len; 210 off_t offset; 211 enum uio_seg segflg; 212 int ioflg; 213 struct ucred *cred; 214 int *aresid; 215 struct proc *p; 216 { 217 struct uio auio; 218 struct iovec aiov; 219 int error; 220 221 if ((ioflg & IO_NODELOCKED) == 0) 222 VOP_LOCK(vp); 223 auio.uio_iov = &aiov; 224 auio.uio_iovcnt = 1; 225 aiov.iov_base = base; 226 aiov.iov_len = len; 227 auio.uio_resid = len; 228 auio.uio_offset = offset; 229 auio.uio_segflg = segflg; 230 auio.uio_rw = rw; 231 auio.uio_procp = p; 232 if (rw == UIO_READ) { 233 error = VOP_READ(vp, &auio, ioflg, cred); 234 } else { 235 error = VOP_WRITE(vp, &auio, ioflg, cred); 236 } 237 if (aresid) 238 *aresid = auio.uio_resid; 239 else 240 if (auio.uio_resid && error == 0) 241 error = EIO; 242 if ((ioflg & IO_NODELOCKED) == 0) 243 VOP_UNLOCK(vp); 244 return (error); 245 } 246 247 /* 248 * File table vnode read routine. 249 */ 250 int 251 vn_read(fp, uio, cred) 252 struct file *fp; 253 struct uio *uio; 254 struct ucred *cred; 255 { 256 register struct vnode *vp = (struct vnode *)fp->f_data; 257 int count, error; 258 259 LEASE_CHECK(vp, uio->uio_procp, cred, LEASE_READ); 260 VOP_LOCK(vp); 261 uio->uio_offset = fp->f_offset; 262 count = uio->uio_resid; 263 error = VOP_READ(vp, uio, (fp->f_flag & FNONBLOCK) ? IO_NDELAY : 0, 264 cred); 265 fp->f_offset += count - uio->uio_resid; 266 VOP_UNLOCK(vp); 267 return (error); 268 } 269 270 /* 271 * File table vnode write routine. 272 */ 273 int 274 vn_write(fp, uio, cred) 275 struct file *fp; 276 struct uio *uio; 277 struct ucred *cred; 278 { 279 register struct vnode *vp = (struct vnode *)fp->f_data; 280 int count, error, ioflag = 0; 281 282 if (vp->v_type == VREG && (fp->f_flag & O_APPEND)) 283 ioflag |= IO_APPEND; 284 if (fp->f_flag & FNONBLOCK) 285 ioflag |= IO_NDELAY; 286 LEASE_CHECK(vp, uio->uio_procp, cred, LEASE_WRITE); 287 VOP_LOCK(vp); 288 uio->uio_offset = fp->f_offset; 289 count = uio->uio_resid; 290 error = VOP_WRITE(vp, uio, ioflag, cred); 291 if (ioflag & IO_APPEND) 292 fp->f_offset = uio->uio_offset; 293 else 294 fp->f_offset += count - uio->uio_resid; 295 VOP_UNLOCK(vp); 296 return (error); 297 } 298 299 /* 300 * File table vnode stat routine. 301 */ 302 int 303 vn_stat(vp, sb, p) 304 struct vnode *vp; 305 register struct stat *sb; 306 struct proc *p; 307 { 308 struct vattr vattr; 309 register struct vattr *vap; 310 int error; 311 u_short mode; 312 313 vap = &vattr; 314 error = VOP_GETATTR(vp, vap, p->p_ucred, p); 315 if (error) 316 return (error); 317 /* 318 * Copy from vattr table 319 */ 320 sb->st_dev = vap->va_fsid; 321 sb->st_ino = vap->va_fileid; 322 mode = vap->va_mode; 323 switch (vp->v_type) { 324 case VREG: 325 mode |= S_IFREG; 326 break; 327 case VDIR: 328 mode |= S_IFDIR; 329 break; 330 case VBLK: 331 mode |= S_IFBLK; 332 break; 333 case VCHR: 334 mode |= S_IFCHR; 335 break; 336 case VLNK: 337 mode |= S_IFLNK; 338 break; 339 case VSOCK: 340 mode |= S_IFSOCK; 341 break; 342 case VFIFO: 343 mode |= S_IFIFO; 344 break; 345 default: 346 return (EBADF); 347 }; 348 sb->st_mode = mode; 349 sb->st_nlink = vap->va_nlink; 350 sb->st_uid = vap->va_uid; 351 sb->st_gid = vap->va_gid; 352 sb->st_rdev = vap->va_rdev; 353 sb->st_size = vap->va_size; 354 sb->st_atimespec = vap->va_atime; 355 sb->st_mtimespec= vap->va_mtime; 356 sb->st_ctimespec = vap->va_ctime; 357 sb->st_blksize = vap->va_blocksize; 358 sb->st_flags = vap->va_flags; 359 sb->st_gen = vap->va_gen; 360 sb->st_blocks = vap->va_bytes / S_BLKSIZE; 361 return (0); 362 } 363 364 /* 365 * File table vnode ioctl routine. 366 */ 367 int 368 vn_ioctl(fp, com, data, p) 369 struct file *fp; 370 int com; 371 caddr_t data; 372 struct proc *p; 373 { 374 register struct vnode *vp = ((struct vnode *)fp->f_data); 375 struct vattr vattr; 376 int error; 377 378 switch (vp->v_type) { 379 380 case VREG: 381 case VDIR: 382 if (com == FIONREAD) { 383 if (error = VOP_GETATTR(vp, &vattr, p->p_ucred, p)) 384 return (error); 385 *(int *)data = vattr.va_size - fp->f_offset; 386 return (0); 387 } 388 if (com == FIONBIO || com == FIOASYNC) /* XXX */ 389 return (0); /* XXX */ 390 /* fall into ... */ 391 392 default: 393 return (ENOTTY); 394 395 case VFIFO: 396 case VCHR: 397 case VBLK: 398 error = VOP_IOCTL(vp, com, data, fp->f_flag, p->p_ucred, p); 399 if (error == 0 && com == TIOCSCTTY) { 400 p->p_session->s_ttyvp = vp; 401 VREF(vp); 402 } 403 return (error); 404 } 405 } 406 407 /* 408 * File table vnode select routine. 409 */ 410 int 411 vn_select(fp, which, p) 412 struct file *fp; 413 int which; 414 struct proc *p; 415 { 416 417 return (VOP_SELECT(((struct vnode *)fp->f_data), which, fp->f_flag, 418 fp->f_cred, p)); 419 } 420 421 /* 422 * File table vnode close routine. 423 */ 424 int 425 vn_closefile(fp, p) 426 struct file *fp; 427 struct proc *p; 428 { 429 430 return (vn_close(((struct vnode *)fp->f_data), fp->f_flag, 431 fp->f_cred, p)); 432 } 433