| 1 | /* sys_generic.c 5.11 82/08/22 */ |
| 2 | |
| 3 | #include "../h/param.h" |
| 4 | #include "../h/systm.h" |
| 5 | #include "../h/dir.h" |
| 6 | #include "../h/user.h" |
| 7 | #include "../h/tty.h" |
| 8 | #include "../h/file.h" |
| 9 | #include "../h/inode.h" |
| 10 | #include "../h/buf.h" |
| 11 | #include "../h/proc.h" |
| 12 | #include "../h/inline.h" |
| 13 | #include "../h/conf.h" |
| 14 | #include "../h/socket.h" |
| 15 | #include "../h/socketvar.h" |
| 16 | #include "../h/fs.h" |
| 17 | #ifdef MUSH |
| 18 | #include "../h/quota.h" |
| 19 | #include "../h/share.h" |
| 20 | #else |
| 21 | #define CHARGE(nothing) |
| 22 | #endif |
| 23 | #include "../h/vlimit.h" |
| 24 | #include "../h/descrip.h" |
| 25 | #include "../h/uio.h" |
| 26 | |
| 27 | /* |
| 28 | * Read system call. |
| 29 | */ |
| 30 | read() |
| 31 | { |
| 32 | register struct a { |
| 33 | int fdes; |
| 34 | char *cbuf; |
| 35 | unsigned count; |
| 36 | } *uap = (struct a *)u.u_ap; |
| 37 | struct uio auio; |
| 38 | struct iovec aiov; |
| 39 | |
| 40 | aiov.iov_base = (caddr_t)uap->cbuf; |
| 41 | aiov.iov_len = uap->count; |
| 42 | auio.uio_iov = &aiov; |
| 43 | auio.uio_iovcnt = 1; |
| 44 | rwuio(&auio, UIO_READ); |
| 45 | } |
| 46 | |
| 47 | readv() |
| 48 | { |
| 49 | register struct a { |
| 50 | int fdes; |
| 51 | struct iovec *iovp; |
| 52 | int iovcnt; |
| 53 | } *uap = (struct a *)u.u_ap; |
| 54 | struct uio auio; |
| 55 | struct iovec aiov[16]; /* XXX */ |
| 56 | |
| 57 | if (uap->iovcnt <= 0 || uap->iovcnt > sizeof(aiov)/sizeof(aiov[0])) { |
| 58 | u.u_error = EINVAL; |
| 59 | return; |
| 60 | } |
| 61 | auio.uio_iov = aiov; |
| 62 | auio.uio_iovcnt = uap->iovcnt; |
| 63 | if (copyin((caddr_t)uap->iovp, (caddr_t)aiov, |
| 64 | (unsigned)(uap->iovcnt * sizeof (struct iovec)))) { |
| 65 | u.u_error = EFAULT; |
| 66 | return; |
| 67 | } |
| 68 | rwuio(&auio, UIO_READ); |
| 69 | } |
| 70 | |
| 71 | /* |
| 72 | * Write system call |
| 73 | */ |
| 74 | write() |
| 75 | { |
| 76 | register struct a { |
| 77 | int fdes; |
| 78 | char *cbuf; |
| 79 | int count; |
| 80 | } *uap = (struct a *)u.u_ap; |
| 81 | struct uio auio; |
| 82 | struct iovec aiov; |
| 83 | |
| 84 | auio.uio_iov = &aiov; |
| 85 | auio.uio_iovcnt = 1; |
| 86 | aiov.iov_base = uap->cbuf; |
| 87 | aiov.iov_len = uap->count; |
| 88 | rwuio(&auio, UIO_WRITE); |
| 89 | } |
| 90 | |
| 91 | writev() |
| 92 | { |
| 93 | register struct a { |
| 94 | int fdes; |
| 95 | struct iovec *iovp; |
| 96 | int iovcnt; |
| 97 | } *uap = (struct a *)u.u_ap; |
| 98 | struct uio auio; |
| 99 | struct iovec aiov[16]; /* XXX */ |
| 100 | |
| 101 | if (uap->iovcnt <= 0 || uap->iovcnt > sizeof(aiov)/sizeof(aiov[0])) { |
| 102 | u.u_error = EINVAL; |
| 103 | return; |
| 104 | } |
| 105 | auio.uio_iov = aiov; |
| 106 | auio.uio_iovcnt = uap->iovcnt; |
| 107 | if (copyin((caddr_t)uap->iovp, (caddr_t)aiov, |
| 108 | (unsigned)(uap->iovcnt * sizeof (struct iovec)))) { |
| 109 | u.u_error = EFAULT; |
| 110 | return; |
| 111 | } |
| 112 | rwuio(&auio, UIO_WRITE); |
| 113 | } |
| 114 | |
| 115 | rwuio(uio, rw) |
| 116 | register struct uio *uio; |
| 117 | enum uio_rw rw; |
| 118 | { |
| 119 | struct a { |
| 120 | int fdes; |
| 121 | }; |
| 122 | register struct file *fp; |
| 123 | register struct iovec *iov; |
| 124 | register struct inode *ip; |
| 125 | int i, count; |
| 126 | |
| 127 | GETF(fp, ((struct a *)u.u_ap)->fdes); |
| 128 | if ((fp->f_flag&(rw==UIO_READ ? FREAD : FWRITE)) == 0) { |
| 129 | u.u_error = EBADF; |
| 130 | return; |
| 131 | } |
| 132 | uio->uio_resid = 0; |
| 133 | uio->uio_segflg = 0; |
| 134 | iov = uio->uio_iov; |
| 135 | for (i = 0; i < uio->uio_iovcnt; i++) { |
| 136 | if (iov->iov_len < 0) { |
| 137 | u.u_error = EINVAL; |
| 138 | return; |
| 139 | } |
| 140 | uio->uio_resid += iov->iov_len; |
| 141 | if (uio->uio_resid < 0) { |
| 142 | u.u_error = EINVAL; |
| 143 | return; |
| 144 | } |
| 145 | } |
| 146 | count = uio->uio_resid; |
| 147 | if ((u.u_procp->p_flag&SNUSIG) && setjmp(u.u_qsav)) { |
| 148 | if (uio->uio_resid == count) |
| 149 | u.u_eosys = RESTARTSYS; |
| 150 | } else if (fp->f_type == DTYPE_SOCKET) { |
| 151 | int sosend(), soreceive(); |
| 152 | u.u_error = |
| 153 | (*(rw==UIO_READ?soreceive:sosend)) |
| 154 | (fp->f_socket, (struct sockaddr *)0, uio); |
| 155 | } else { |
| 156 | ip = fp->f_inode; |
| 157 | uio->uio_offset = fp->f_offset; |
| 158 | if ((ip->i_mode&IFMT) == IFREG) { |
| 159 | ilock(ip); |
| 160 | u.u_error = rwip(ip, uio, rw); |
| 161 | iunlock(ip); |
| 162 | } else |
| 163 | u.u_error = rwip(ip, uio, rw); |
| 164 | fp->f_offset += count - uio->uio_resid; |
| 165 | } |
| 166 | u.u_r.r_val1 = count - uio->uio_resid; |
| 167 | } |
| 168 | |
| 169 | rdwri(rw, ip, base, len, offset, segflg, aresid) |
| 170 | struct inode *ip; |
| 171 | caddr_t base; |
| 172 | int len, offset, segflg; |
| 173 | int *aresid; |
| 174 | enum uio_rw rw; |
| 175 | { |
| 176 | struct uio auio; |
| 177 | struct iovec aiov; |
| 178 | int error; |
| 179 | |
| 180 | auio.uio_iov = &aiov; |
| 181 | auio.uio_iovcnt = 1; |
| 182 | aiov.iov_base = base; |
| 183 | aiov.iov_len = len; |
| 184 | auio.uio_resid = len; |
| 185 | auio.uio_offset = offset; |
| 186 | auio.uio_segflg = segflg; |
| 187 | error = rwip(ip, &auio, rw); |
| 188 | if (aresid) |
| 189 | *aresid = auio.uio_resid; |
| 190 | else |
| 191 | if (auio.uio_resid) |
| 192 | error = EIO; |
| 193 | return (error); |
| 194 | } |
| 195 | |
| 196 | rwip(ip, uio, rw) |
| 197 | register struct inode *ip; |
| 198 | register struct uio *uio; |
| 199 | enum uio_rw rw; |
| 200 | { |
| 201 | dev_t dev = (dev_t)ip->i_rdev; |
| 202 | struct buf *bp; |
| 203 | struct fs *fs; |
| 204 | daddr_t lbn, bn; |
| 205 | register int on, type; |
| 206 | register unsigned n; |
| 207 | int size; |
| 208 | long bsize; |
| 209 | extern int mem_no; |
| 210 | int error = 0; |
| 211 | |
| 212 | if (rw != UIO_READ && rw != UIO_WRITE) |
| 213 | panic("rwip"); |
| 214 | if (uio->uio_offset < 0 && |
| 215 | ((ip->i_mode&IFMT) != IFCHR || mem_no != major(dev))) |
| 216 | return (EINVAL); if (rw == UIO_READ) |
| 217 | ip->i_flag |= IACC; |
| 218 | type = ip->i_mode&IFMT; |
| 219 | if (type == IFCHR) { |
| 220 | #ifdef QUOTA |
| 221 | register c = uio->uio_resid; |
| 222 | #endif |
| 223 | if (rw == UIO_READ) |
| 224 | (*cdevsw[major(dev)].d_read)(dev, uio); |
| 225 | else { |
| 226 | ip->i_flag |= IUPD|ICHG; |
| 227 | (*cdevsw[major(dev)].d_write)(dev, uio); |
| 228 | } |
| 229 | CHARGE(sc_tio * (c - uio->uio_resid)); |
| 230 | return (u.u_error); |
| 231 | } |
| 232 | if (rw == UIO_WRITE && type == IFREG && |
| 233 | uio->uio_offset + uio->uio_resid > u.u_limit[LIM_FSIZE]) { |
| 234 | psignal(u.u_procp, SIGXFSZ); |
| 235 | return (EMFILE); |
| 236 | } |
| 237 | if (type != IFBLK) { |
| 238 | dev = ip->i_dev; |
| 239 | fs = ip->i_fs; |
| 240 | bsize = fs->fs_bsize; |
| 241 | } else |
| 242 | bsize = BLKDEV_IOSIZE; |
| 243 | do { |
| 244 | lbn = uio->uio_offset / bsize; |
| 245 | on = uio->uio_offset % bsize; |
| 246 | n = MIN((unsigned)(bsize - on), uio->uio_resid); |
| 247 | if (type != IFBLK) { |
| 248 | if (rw == UIO_READ) { |
| 249 | int diff = ip->i_size - uio->uio_offset; |
| 250 | if (diff <= 0) |
| 251 | return (0); |
| 252 | if (diff < n) |
| 253 | n = diff; |
| 254 | } |
| 255 | bn = fsbtodb(fs, |
| 256 | bmap(ip, lbn, rw == UIO_WRITE ? B_WRITE: B_READ, (int)(on+n))); |
| 257 | if (u.u_error || rw == UIO_WRITE && (long)bn<0) |
| 258 | return (u.u_error); |
| 259 | if (rw == UIO_WRITE && uio->uio_offset + n > ip->i_size && |
| 260 | (type == IFDIR || type == IFREG || type == IFLNK)) |
| 261 | ip->i_size = uio->uio_offset + n; |
| 262 | size = blksize(fs, ip, lbn); |
| 263 | } else { |
| 264 | bn = lbn * (BLKDEV_IOSIZE/DEV_BSIZE); |
| 265 | rablock = bn + (BLKDEV_IOSIZE/DEV_BSIZE); |
| 266 | rasize = size = bsize; |
| 267 | } |
| 268 | if (rw == UIO_READ) { |
| 269 | if ((long)bn<0) { |
| 270 | bp = geteblk(size); |
| 271 | clrbuf(bp); |
| 272 | } else if (ip->i_lastr + 1 == lbn) |
| 273 | bp = breada(dev, bn, size, rablock, rasize); |
| 274 | else |
| 275 | bp = bread(dev, bn, size); |
| 276 | ip->i_lastr = lbn; |
| 277 | } else { |
| 278 | int i, count; |
| 279 | |
| 280 | count = howmany(size, DEV_BSIZE); |
| 281 | for (i = 0; i < count; i += CLSIZE) |
| 282 | if (mfind(dev, bn + i)) |
| 283 | munhash(dev, bn + i); |
| 284 | if (n == bsize) |
| 285 | bp = getblk(dev, bn, size); |
| 286 | else |
| 287 | bp = bread(dev, bn, size); |
| 288 | } |
| 289 | n = MIN(n, size - bp->b_resid); |
| 290 | if (bp->b_flags & B_ERROR) { |
| 291 | error = EIO; |
| 292 | brelse(bp); |
| 293 | goto bad; |
| 294 | } |
| 295 | u.u_error = |
| 296 | uiomove(bp->b_un.b_addr+on, (u_int)n, rw, uio); |
| 297 | if (rw == UIO_READ) { |
| 298 | if (n + on == bsize || uio->uio_offset == ip->i_size) |
| 299 | bp->b_flags |= B_AGE; |
| 300 | brelse(bp); |
| 301 | } else { |
| 302 | if ((ip->i_mode&IFMT) == IFDIR) |
| 303 | bwrite(bp); |
| 304 | else if (n + on == bsize) { |
| 305 | bp->b_flags |= B_AGE; |
| 306 | bawrite(bp); |
| 307 | } else |
| 308 | bdwrite(bp); |
| 309 | ip->i_flag |= IUPD|ICHG; |
| 310 | if (u.u_ruid != 0) |
| 311 | ip->i_mode &= ~(ISUID|ISGID); |
| 312 | } |
| 313 | } while (u.u_error == 0 && uio->uio_resid > 0 && n != 0); |
| 314 | bad: |
| 315 | return (error); |
| 316 | } |
| 317 | |
| 318 | uiomove(cp, n, rw, uio) |
| 319 | register caddr_t cp; |
| 320 | register int n; |
| 321 | enum uio_rw rw; |
| 322 | register struct uio *uio; |
| 323 | { |
| 324 | register struct iovec *iov; |
| 325 | int error; |
| 326 | u_int cnt; |
| 327 | |
| 328 | while (n > 0 && uio->uio_resid) { |
| 329 | iov = uio->uio_iov; |
| 330 | cnt = iov->iov_len; |
| 331 | if (cnt == 0) { |
| 332 | uio->uio_iov++; |
| 333 | uio->uio_iovcnt--; |
| 334 | continue; |
| 335 | } |
| 336 | if (cnt > n) |
| 337 | cnt = n; |
| 338 | switch (uio->uio_segflg) { |
| 339 | |
| 340 | case 0: |
| 341 | case 2: |
| 342 | if (rw == UIO_READ) |
| 343 | error = copyout(cp, iov->iov_base, cnt); |
| 344 | else |
| 345 | error = copyin(iov->iov_base, cp, cnt); |
| 346 | if (error) |
| 347 | return (error); |
| 348 | break; |
| 349 | |
| 350 | case 1: |
| 351 | if (rw == UIO_READ) |
| 352 | bcopy((caddr_t)cp, iov->iov_base, cnt); |
| 353 | else |
| 354 | bcopy(iov->iov_base, (caddr_t)cp, cnt); |
| 355 | break; |
| 356 | } |
| 357 | iov->iov_base += cnt; |
| 358 | iov->iov_len -= cnt; |
| 359 | uio->uio_resid -= cnt; |
| 360 | uio->uio_offset += cnt; |
| 361 | cp += cnt; |
| 362 | n -= cnt; |
| 363 | } |
| 364 | return (error); |
| 365 | } |
| 366 | |
| 367 | /* |
| 368 | * Give next character to user as result of read. |
| 369 | */ |
| 370 | ureadc(c, uio) |
| 371 | register int c; |
| 372 | register struct uio *uio; |
| 373 | { |
| 374 | register struct iovec *iov; |
| 375 | |
| 376 | again: |
| 377 | if (uio->uio_iovcnt == 0) |
| 378 | panic("ureadc"); |
| 379 | iov = uio->uio_iov; |
| 380 | if (iov->iov_len <= 0 || uio->uio_resid <= 0) { |
| 381 | uio->uio_iovcnt--; |
| 382 | uio->uio_iov++; |
| 383 | goto again; |
| 384 | } |
| 385 | switch (uio->uio_segflg) { |
| 386 | |
| 387 | case 0: |
| 388 | if (subyte(iov->iov_base, c) < 0) |
| 389 | return (EFAULT); |
| 390 | break; |
| 391 | |
| 392 | case 1: |
| 393 | *iov->iov_base = c; |
| 394 | break; |
| 395 | |
| 396 | case 2: |
| 397 | if (suibyte(iov->iov_base, c) < 0) |
| 398 | return (EFAULT); |
| 399 | break; |
| 400 | } |
| 401 | iov->iov_base++; |
| 402 | iov->iov_len--; |
| 403 | uio->uio_resid--; |
| 404 | uio->uio_offset++; |
| 405 | return (0); |
| 406 | } |
| 407 | |
| 408 | /* |
| 409 | * Get next character written in by user from uio. |
| 410 | */ |
| 411 | uwritec(uio) |
| 412 | struct uio *uio; |
| 413 | { |
| 414 | register struct iovec *iov; |
| 415 | register int c; |
| 416 | |
| 417 | again: |
| 418 | if (uio->uio_iovcnt <= 0 || uio->uio_resid <= 0) |
| 419 | panic("uwritec"); |
| 420 | iov = uio->uio_iov; |
| 421 | if (iov->iov_len == 0) { |
| 422 | uio->uio_iovcnt--; |
| 423 | uio->uio_iov++; |
| 424 | goto again; |
| 425 | } |
| 426 | switch (uio->uio_segflg) { |
| 427 | |
| 428 | case 0: |
| 429 | c = fubyte(iov->iov_base); |
| 430 | break; |
| 431 | |
| 432 | case 1: |
| 433 | c = *iov->iov_base & 0377; |
| 434 | break; |
| 435 | |
| 436 | case 2: |
| 437 | c = fuibyte(iov->iov_base); |
| 438 | break; |
| 439 | } |
| 440 | if (c < 0) |
| 441 | return (-1); |
| 442 | iov->iov_base++; |
| 443 | iov->iov_len--; |
| 444 | uio->uio_resid--; |
| 445 | uio->uio_offset++; |
| 446 | return (c & 0377); |
| 447 | } |
| 448 | |
| 449 | /* |
| 450 | * Ioctl system call |
| 451 | * Check legality, execute common code, |
| 452 | * and switch out to individual device routine. |
| 453 | */ |
| 454 | ioctl() |
| 455 | { |
| 456 | register struct file *fp; |
| 457 | struct a { |
| 458 | int fdes; |
| 459 | int cmd; |
| 460 | caddr_t cmarg; |
| 461 | } *uap; |
| 462 | register int com; |
| 463 | register u_int size; |
| 464 | char data[IOCPARM_MASK+1]; |
| 465 | |
| 466 | uap = (struct a *)u.u_ap; |
| 467 | if ((fp = getf(uap->fdes)) == NULL) |
| 468 | return; |
| 469 | if ((fp->f_flag & (FREAD|FWRITE)) == 0) { |
| 470 | u.u_error = EBADF; |
| 471 | return; |
| 472 | } |
| 473 | com = uap->cmd; |
| 474 | |
| 475 | #ifndef NOCOMPAT |
| 476 | /* |
| 477 | * Map old style ioctl's into new for the |
| 478 | * sake of backwards compatibility (sigh). |
| 479 | */ |
| 480 | if ((com&~0xffff) == 0) { |
| 481 | com = mapioctl(com); |
| 482 | if (com == 0) { |
| 483 | u.u_error = EINVAL; |
| 484 | return; |
| 485 | } |
| 486 | } |
| 487 | #endif |
| 488 | if (com == FIOCLEX) { |
| 489 | u.u_pofile[uap->fdes] |= EXCLOSE; |
| 490 | return; |
| 491 | } |
| 492 | if (com == FIONCLEX) { |
| 493 | u.u_pofile[uap->fdes] &= ~EXCLOSE; |
| 494 | return; |
| 495 | } |
| 496 | |
| 497 | /* |
| 498 | * Interpret high order word to find |
| 499 | * amount of data to be copied to/from the |
| 500 | * user's address space. |
| 501 | */ |
| 502 | size = (com &~ (IOC_INOUT|IOC_VOID)) >> 16; |
| 503 | if (size > sizeof (data)) { |
| 504 | u.u_error = EFAULT; |
| 505 | return; |
| 506 | } |
| 507 | if (com&IOC_IN && size) { |
| 508 | if (copyin(uap->cmarg, (caddr_t)data, (u_int)size)) { |
| 509 | u.u_error = EFAULT; |
| 510 | return; |
| 511 | } |
| 512 | } else |
| 513 | *(caddr_t *)data = uap->cmarg; |
| 514 | /* |
| 515 | * Zero the buffer on the stack so the user |
| 516 | * always gets back something deterministic. |
| 517 | */ |
| 518 | if ((com&IOC_OUT) && size) |
| 519 | bzero((caddr_t)data, size); |
| 520 | |
| 521 | if (fp->f_type == DTYPE_SOCKET) |
| 522 | soioctl(fp->f_socket, com, data); |
| 523 | else { |
| 524 | register struct inode *ip = fp->f_inode; |
| 525 | int fmt = ip->i_mode & IFMT; |
| 526 | dev_t dev; |
| 527 | |
| 528 | if (fmt != IFCHR) { |
| 529 | if (com == FIONREAD && (fmt == IFREG || fmt == IFDIR)) { |
| 530 | *(off_t *)data = ip->i_size - fp->f_offset; |
| 531 | goto returndata; |
| 532 | } |
| 533 | if (com != FIONBIO && com != FIOASYNC) |
| 534 | u.u_error = ENOTTY; |
| 535 | return; |
| 536 | } |
| 537 | dev = ip->i_rdev; |
| 538 | u.u_r.r_val1 = 0; |
| 539 | if ((u.u_procp->p_flag&SNUSIG) && setjmp(u.u_qsav)) { |
| 540 | u.u_eosys = RESTARTSYS; |
| 541 | return; |
| 542 | } |
| 543 | (*cdevsw[major(dev)].d_ioctl)(dev, com, data, 0); |
| 544 | } |
| 545 | |
| 546 | returndata: |
| 547 | /* |
| 548 | * Copy any data to user, size was |
| 549 | * already set and checked above. |
| 550 | */ |
| 551 | if (u.u_error == 0 && (com&IOC_OUT)) |
| 552 | if (size && copyout(data, uap->cmarg, (u_int)size)) |
| 553 | u.u_error = EFAULT; |
| 554 | } |
| 555 | |
| 556 | /* |
| 557 | * Do nothing specific version of line |
| 558 | * discipline specific ioctl command. |
| 559 | */ |
| 560 | /*ARGSUSED*/ |
| 561 | nullioctl(tp, cmd, data, flags) |
| 562 | struct tty *tp; |
| 563 | char *data; |
| 564 | int flags; |
| 565 | { |
| 566 | |
| 567 | #ifdef lint |
| 568 | tp = tp; data = data; flags = flags; |
| 569 | #endif |
| 570 | return (cmd); |
| 571 | } |