drivers/tty/vt/vc_screen.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Provide access to virtual console memory.
   4  * /dev/vcs0: the screen as it is being viewed right now (possibly scrolled)
   5  * /dev/vcsN: the screen of /dev/ttyN (1 <= N <= 63)
   6  *            [minor: N]
   7  *
   8  * /dev/vcsaN: idem, but including attributes, and prefixed with
   9  *      the 4 bytes lines,columns,x,y (as screendump used to give).
  10  *      Attribute/character pair is in native endianity.
  11  *            [minor: N+128]
  12  *
  13  * /dev/vcsuN: similar to /dev/vcsaN but using 4-byte unicode values
  14  *      instead of 1-byte screen glyph values.
  15  *            [minor: N+64]
  16  *
  17  * /dev/vcsuaN: same idea as /dev/vcsaN for unicode (not yet implemented).
  18  *
  19  * This replaces screendump and part of selection, so that the system
  20  * administrator can control access using file system permissions.
  21  *
  22  * aeb@cwi.nl - efter Friedas begravelse - 950211
  23  *
  24  * machek@k332.feld.cvut.cz - modified not to send characters to wrong console
  25  *       - fixed some fatal off-by-one bugs (0-- no longer == -1 -> looping and looping and looping...)
  26  *       - making it shorter - scr_readw are macros which expand in PRETTY long code
  27  */
  28
  29 #include <linux/kernel.h>
  30 #include <linux/major.h>
  31 #include <linux/errno.h>
  32 #include <linux/export.h>
  33 #include <linux/tty.h>
  34 #include <linux/interrupt.h>
  35 #include <linux/mm.h>
  36 #include <linux/init.h>
  37 #include <linux/vt_kern.h>
  38 #include <linux/selection.h>
  39 #include <linux/kbd_kern.h>
  40 #include <linux/console.h>
  41 #include <linux/device.h>
  42 #include <linux/sched.h>
  43 #include <linux/fs.h>
  44 #include <linux/poll.h>
  45 #include <linux/signal.h>
  46 #include <linux/slab.h>
  47 #include <linux/notifier.h>
  48
  49 #include <linux/uaccess.h>
  50 #include <asm/byteorder.h>
  51 #include <asm/unaligned.h>
  52
  53 #undef attr
  54 #undef org
  55 #undef addr
  56 #define HEADER_SIZE     4
  57
  58 #define CON_BUF_SIZE (CONFIG_BASE_SMALL ? 256 : PAGE_SIZE)
  59
  60 /*
  61  * Our minor space:
  62  *
  63  *   0 ... 63   glyph mode without attributes
  64  *  64 ... 127  unicode mode without attributes
  65  * 128 ... 191  glyph mode with attributes
  66  * 192 ... 255  unused (reserved for unicode with attributes)
  67  *
  68  * This relies on MAX_NR_CONSOLES being  <= 63, meaning 63 actual consoles
  69  * with minors 0, 64, 128 and 192 being proxies for the foreground console.
  70  */
  71 #if MAX_NR_CONSOLES > 63
  72 #warning "/dev/vcs* devices may not accommodate more than 63 consoles"
  73 #endif
  74
  75 #define console(inode)          (iminor(inode) & 63)
  76 #define use_unicode(inode)      (iminor(inode) & 64)
  77 #define use_attributes(inode)   (iminor(inode) & 128)
  78
  79
  80 struct vcs_poll_data {
  81         struct notifier_block notifier;
  82         unsigned int cons_num;
  83         bool seen_last_update;
  84         wait_queue_head_t waitq;
  85         struct fasync_struct *fasync;
  86 };
  87
  88 static int
  89 vcs_notifier(struct notifier_block *nb, unsigned long code, void *_param)
  90 {
  91         struct vt_notifier_param *param = _param;
  92         struct vc_data *vc = param->vc;
  93         struct vcs_poll_data *poll =
  94                 container_of(nb, struct vcs_poll_data, notifier);
  95         int currcons = poll->cons_num;
  96
  97         if (code != VT_UPDATE)
  98                 return NOTIFY_DONE;
  99
 100         if (currcons == 0)
 101                 currcons = fg_console;
 102         else
 103                 currcons--;
 104         if (currcons != vc->vc_num)
 105                 return NOTIFY_DONE;
 106
 107         poll->seen_last_update = false;
 108         wake_up_interruptible(&poll->waitq);
 109         kill_fasync(&poll->fasync, SIGIO, POLL_IN);
 110         return NOTIFY_OK;
 111 }
 112
 113 static void
 114 vcs_poll_data_free(struct vcs_poll_data *poll)
 115 {
 116         unregister_vt_notifier(&poll->notifier);
 117         kfree(poll);
 118 }
 119
 120 static struct vcs_poll_data *
 121 vcs_poll_data_get(struct file *file)
 122 {
 123         struct vcs_poll_data *poll = file->private_data, *kill = NULL;
 124
 125         if (poll)
 126                 return poll;
 127
 128         poll = kzalloc(sizeof(*poll), GFP_KERNEL);
 129         if (!poll)
 130                 return NULL;
 131         poll->cons_num = console(file_inode(file));
 132         init_waitqueue_head(&poll->waitq);
 133         poll->notifier.notifier_call = vcs_notifier;
 134         if (register_vt_notifier(&poll->notifier) != 0) {
 135                 kfree(poll);
 136                 return NULL;
 137         }
 138
 139         /*
 140          * This code may be called either through ->poll() or ->fasync().
 141          * If we have two threads using the same file descriptor, they could
 142          * both enter this function, both notice that the structure hasn't
 143          * been allocated yet and go ahead allocating it in parallel, but
 144          * only one of them must survive and be shared otherwise we'd leak
 145          * memory with a dangling notifier callback.
 146          */
 147         spin_lock(&file->f_lock);
 148         if (!file->private_data) {
 149                 file->private_data = poll;
 150         } else {
 151                 /* someone else raced ahead of us */
 152                 kill = poll;
 153                 poll = file->private_data;
 154         }
 155         spin_unlock(&file->f_lock);
 156         if (kill)
 157                 vcs_poll_data_free(kill);
 158
 159         return poll;
 160 }
 161
 162 /*
 163  * Returns VC for inode.
 164  * Must be called with console_lock.
 165  */
 166 static struct vc_data*
 167 vcs_vc(struct inode *inode, int *viewed)
 168 {
 169         unsigned int currcons = console(inode);
 170
 171         WARN_CONSOLE_UNLOCKED();
 172
 173         if (currcons == 0) {
 174                 currcons = fg_console;
 175                 if (viewed)
 176                         *viewed = 1;
 177         } else {
 178                 currcons--;
 179                 if (viewed)
 180                         *viewed = 0;
 181         }
 182         return vc_cons[currcons].d;
 183 }
 184
 185 /**
 186  * vcs_size -- return size for a VC in @vc
 187  * @vc: which VC
 188  * @attr: does it use attributes?
 189  * @unicode: is it unicode?
 190  *
 191  * Must be called with console_lock.
 192  */
 193 static int vcs_size(const struct vc_data *vc, bool attr, bool unicode)
 194 {
 195         int size;
 196
 197         WARN_CONSOLE_UNLOCKED();
 198
 199         size = vc->vc_rows * vc->vc_cols;
 200
 201         if (attr) {
 202                 if (unicode)
 203                         return -EOPNOTSUPP;
 204
 205                 size = 2 * size + HEADER_SIZE;
 206         } else if (unicode)
 207                 size *= 4;
 208
 209         return size;
 210 }
 211
 212 static loff_t vcs_lseek(struct file *file, loff_t offset, int orig)
 213 {
 214         struct inode *inode = file_inode(file);
 215         struct vc_data *vc;
 216         int size;
 217
 218         console_lock();
 219         vc = vcs_vc(inode, NULL);
 220         if (!vc) {
 221                 console_unlock();
 222                 return -ENXIO;
 223         }
 224
 225         size = vcs_size(vc, use_attributes(inode), use_unicode(inode));
 226         console_unlock();
 227         if (size < 0)
 228                 return size;
 229         return fixed_size_llseek(file, offset, orig, size);
 230 }
 231
 232
 233 static ssize_t
 234 vcs_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
 235 {
 236         struct inode *inode = file_inode(file);
 237         struct vc_data *vc;
 238         struct vcs_poll_data *poll;
 239         long pos, read;
 240         int attr, uni_mode, row, col, maxcol, viewed;
 241         unsigned short *org = NULL;
 242         ssize_t ret;
 243         char *con_buf;
 244
 245         con_buf = (char *) __get_free_page(GFP_KERNEL);
 246         if (!con_buf)
 247                 return -ENOMEM;
 248
 249         pos = *ppos;
 250
 251         /* Select the proper current console and verify
 252          * sanity of the situation under the console lock.
 253          */
 254         console_lock();
 255
 256         uni_mode = use_unicode(inode);
 257         attr = use_attributes(inode);
 258
 259         ret = -EINVAL;
 260         if (pos < 0)
 261                 goto unlock_out;
 262         /* we enforce 32-bit alignment for pos and count in unicode mode */
 263         if (uni_mode && (pos | count) & 3)
 264                 goto unlock_out;
 265
 266         poll = file->private_data;
 267         if (count && poll)
 268                 poll->seen_last_update = true;
 269         read = 0;
 270         ret = 0;
 271         while (count) {
 272                 char *con_buf0, *con_buf_start;
 273                 long this_round, size;
 274                 ssize_t orig_count;
 275                 long p = pos;
 276
 277                 vc = vcs_vc(inode, &viewed);
 278                 if (!vc) {
 279                         ret = -ENXIO;
 280                         break;
 281                 }
 282
 283                 /* Check whether we are above size each round,
 284                  * as copy_to_user at the end of this loop
 285                  * could sleep.
 286                  */
 287                 size = vcs_size(vc, attr, uni_mode);
 288                 if (size < 0) {
 289                         ret = size;
 290                         break;
 291                 }
 292                 if (pos >= size)
 293                         break;
 294                 if (count > size - pos)
 295                         count = size - pos;
 296
 297                 this_round = count;
 298                 if (this_round > CON_BUF_SIZE)
 299                         this_round = CON_BUF_SIZE;
 300
 301                 /* Perform the whole read into the local con_buf.
 302                  * Then we can drop the console spinlock and safely
 303                  * attempt to move it to userspace.
 304                  */
 305
 306                 con_buf_start = con_buf0 = con_buf;
 307                 orig_count = this_round;
 308                 maxcol = vc->vc_cols;
 309                 if (uni_mode) {
 310                         unsigned int nr;
 311
 312                         ret = vc_uniscr_check(vc);
 313                         if (ret)
 314                                 break;
 315                         p /= 4;
 316                         row = p / vc->vc_cols;
 317                         col = p % maxcol;
 318                         nr = maxcol - col;
 319                         do {
 320                                 if (nr > this_round/4)
 321                                         nr = this_round/4;
 322                                 vc_uniscr_copy_line(vc, con_buf0, viewed,
 323                                                     row, col, nr);
 324                                 con_buf0 += nr * 4;
 325                                 this_round -= nr * 4;
 326                                 row++;
 327                                 col = 0;
 328                                 nr = maxcol;
 329                         } while (this_round);
 330                 } else if (!attr) {
 331                         org = screen_pos(vc, p, viewed);
 332                         col = p % maxcol;
 333                         p += maxcol - col;
 334                         while (this_round-- > 0) {
 335                                 *con_buf0++ = (vcs_scr_readw(vc, org++) & 0xff);
 336                                 if (++col == maxcol) {
 337                                         org = screen_pos(vc, p, viewed);
 338                                         col = 0;
 339                                         p += maxcol;
 340                                 }
 341                         }
 342                 } else {
 343                         if (p < HEADER_SIZE) {
 344                                 size_t tmp_count;
 345
 346                                 con_buf0[0] = (char)vc->vc_rows;
 347                                 con_buf0[1] = (char)vc->vc_cols;
 348                                 getconsxy(vc, con_buf0 + 2);
 349
 350                                 con_buf_start += p;
 351                                 this_round += p;
 352                                 if (this_round > CON_BUF_SIZE) {
 353                                         this_round = CON_BUF_SIZE;
 354                                         orig_count = this_round - p;
 355                                 }
 356
 357                                 tmp_count = HEADER_SIZE;
 358                                 if (tmp_count > this_round)
 359                                         tmp_count = this_round;
 360
 361                                 /* Advance state pointers and move on. */
 362                                 this_round -= tmp_count;
 363                                 p = HEADER_SIZE;
 364                                 con_buf0 = con_buf + HEADER_SIZE;
 365                                 /* If this_round >= 0, then p is even... */
 366                         } else if (p & 1) {
 367                                 /* Skip first byte for output if start address is odd
 368                                  * Update region sizes up/down depending on free
 369                                  * space in buffer.
 370                                  */
 371                                 con_buf_start++;
 372                                 if (this_round < CON_BUF_SIZE)
 373                                         this_round++;
 374                                 else
 375                                         orig_count--;
 376                         }
 377                         if (this_round > 0) {
 378                                 unsigned short *tmp_buf = (unsigned short *)con_buf0;
 379
 380                                 p -= HEADER_SIZE;
 381                                 p /= 2;
 382                                 col = p % maxcol;
 383
 384                                 org = screen_pos(vc, p, viewed);
 385                                 p += maxcol - col;
 386
 387                                 /* Buffer has even length, so we can always copy
 388                                  * character + attribute. We do not copy last byte
 389                                  * to userspace if this_round is odd.
 390                                  */
 391                                 this_round = (this_round + 1) >> 1;
 392
 393                                 while (this_round) {
 394                                         *tmp_buf++ = vcs_scr_readw(vc, org++);
 395                                         this_round --;
 396                                         if (++col == maxcol) {
 397                                                 org = screen_pos(vc, p, viewed);
 398                                                 col = 0;
 399                                                 p += maxcol;
 400                                         }
 401                                 }
 402                         }
 403                 }
 404
 405                 /* Finally, release the console semaphore while we push
 406                  * all the data to userspace from our temporary buffer.
 407                  *
 408                  * AKPM: Even though it's a semaphore, we should drop it because
 409                  * the pagefault handling code may want to call printk().
 410                  */
 411
 412                 console_unlock();
 413                 ret = copy_to_user(buf, con_buf_start, orig_count);
 414                 console_lock();
 415
 416                 if (ret) {
 417                         read += (orig_count - ret);
 418                         ret = -EFAULT;
 419                         break;
 420                 }
 421                 buf += orig_count;
 422                 pos += orig_count;
 423                 read += orig_count;
 424                 count -= orig_count;
 425         }
 426         *ppos += read;
 427         if (read)
 428                 ret = read;
 429 unlock_out:
 430         console_unlock();
 431         free_page((unsigned long) con_buf);
 432         return ret;
 433 }
 434
 435 static ssize_t
 436 vcs_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos)
 437 {
 438         struct inode *inode = file_inode(file);
 439         struct vc_data *vc;
 440         long pos;
 441         long attr, size, written;
 442         char *con_buf0;
 443         int col, maxcol, viewed;
 444         u16 *org0 = NULL, *org = NULL;
 445         size_t ret;
 446         char *con_buf;
 447
 448         if (use_unicode(inode))
 449                 return -EOPNOTSUPP;
 450
 451         con_buf = (char *) __get_free_page(GFP_KERNEL);
 452         if (!con_buf)
 453                 return -ENOMEM;
 454
 455         pos = *ppos;
 456
 457         /* Select the proper current console and verify
 458          * sanity of the situation under the console lock.
 459          */
 460         console_lock();
 461
 462         attr = use_attributes(inode);
 463         ret = -ENXIO;
 464         vc = vcs_vc(inode, &viewed);
 465         if (!vc)
 466                 goto unlock_out;
 467
 468         size = vcs_size(vc, attr, false);
 469         if (size < 0) {
 470                 ret = size;
 471                 goto unlock_out;
 472         }
 473         ret = -EINVAL;
 474         if (pos < 0 || pos > size)
 475                 goto unlock_out;
 476         if (count > size - pos)
 477                 count = size - pos;
 478         written = 0;
 479         while (count) {
 480                 long this_round = count;
 481                 size_t orig_count;
 482                 long p;
 483
 484                 if (this_round > CON_BUF_SIZE)
 485                         this_round = CON_BUF_SIZE;
 486
 487                 /* Temporarily drop the console lock so that we can read
 488                  * in the write data from userspace safely.
 489                  */
 490                 console_unlock();
 491                 ret = copy_from_user(con_buf, buf, this_round);
 492                 console_lock();
 493
 494                 if (ret) {
 495                         this_round -= ret;
 496                         if (!this_round) {
 497                                 /* Abort loop if no data were copied. Otherwise
 498                                  * fail with -EFAULT.
 499                                  */
 500                                 if (written)
 501                                         break;
 502                                 ret = -EFAULT;
 503                                 goto unlock_out;
 504                         }
 505                 }
 506
 507                 /* The vc might have been freed or vcs_size might have changed
 508                  * while we slept to grab the user buffer, so recheck.
 509                  * Return data written up to now on failure.
 510                  */
 511                 vc = vcs_vc(inode, &viewed);
 512                 if (!vc) {
 513                         if (written)
 514                                 break;
 515                         ret = -ENXIO;
 516                         goto unlock_out;
 517                 }
 518                 size = vcs_size(vc, attr, false);
 519                 if (size < 0) {
 520                         if (written)
 521                                 break;
 522                         ret = size;
 523                         goto unlock_out;
 524                 }
 525                 if (pos >= size)
 526                         break;
 527                 if (this_round > size - pos)
 528                         this_round = size - pos;
 529
 530                 /* OK, now actually push the write to the console
 531                  * under the lock using the local kernel buffer.
 532                  */
 533
 534                 con_buf0 = con_buf;
 535                 orig_count = this_round;
 536                 maxcol = vc->vc_cols;
 537                 p = pos;
 538                 if (!attr) {
 539                         org0 = org = screen_pos(vc, p, viewed);
 540                         col = p % maxcol;
 541                         p += maxcol - col;
 542
 543                         while (this_round > 0) {
 544                                 unsigned char c = *con_buf0++;
 545
 546                                 this_round--;
 547                                 vcs_scr_writew(vc,
 548                                                (vcs_scr_readw(vc, org) & 0xff00) | c, org);
 549                                 org++;
 550                                 if (++col == maxcol) {
 551                                         org = screen_pos(vc, p, viewed);
 552                                         col = 0;
 553                                         p += maxcol;
 554                                 }
 555                         }
 556                 } else {
 557                         if (p < HEADER_SIZE) {
 558                                 char header[HEADER_SIZE];
 559
 560                                 getconsxy(vc, header + 2);
 561                                 while (p < HEADER_SIZE && this_round > 0) {
 562                                         this_round--;
 563                                         header[p++] = *con_buf0++;
 564                                 }
 565                                 if (!viewed)
 566                                         putconsxy(vc, header + 2);
 567                         }
 568                         p -= HEADER_SIZE;
 569                         col = (p/2) % maxcol;
 570                         if (this_round > 0) {
 571                                 org0 = org = screen_pos(vc, p/2, viewed);
 572                                 if ((p & 1) && this_round > 0) {
 573                                         char c;
 574
 575                                         this_round--;
 576                                         c = *con_buf0++;
 577 #ifdef __BIG_ENDIAN
 578                                         vcs_scr_writew(vc, c |
 579                                              (vcs_scr_readw(vc, org) & 0xff00), org);
 580 #else
 581                                         vcs_scr_writew(vc, (c << 8) |
 582                                              (vcs_scr_readw(vc, org) & 0xff), org);
 583 #endif
 584                                         org++;
 585                                         p++;
 586                                         if (++col == maxcol) {
 587                                                 org = screen_pos(vc, p/2, viewed);
 588                                                 col = 0;
 589                                         }
 590                                 }
 591                                 p /= 2;
 592                                 p += maxcol - col;
 593                         }
 594                         while (this_round > 1) {
 595                                 unsigned short w;
 596
 597                                 w = get_unaligned(((unsigned short *)con_buf0));
 598                                 vcs_scr_writew(vc, w, org++);
 599                                 con_buf0 += 2;
 600                                 this_round -= 2;
 601                                 if (++col == maxcol) {
 602                                         org = screen_pos(vc, p, viewed);
 603                                         col = 0;
 604                                         p += maxcol;
 605                                 }
 606                         }
 607                         if (this_round > 0) {
 608                                 unsigned char c;
 609
 610                                 c = *con_buf0++;
 611 #ifdef __BIG_ENDIAN
 612                                 vcs_scr_writew(vc, (vcs_scr_readw(vc, org) & 0xff) | (c << 8), org);
 613 #else
 614                                 vcs_scr_writew(vc, (vcs_scr_readw(vc, org) & 0xff00) | c, org);
 615 #endif
 616                         }
 617                 }
 618                 count -= orig_count;
 619                 written += orig_count;
 620                 buf += orig_count;
 621                 pos += orig_count;
 622                 if (org0)
 623                         update_region(vc, (unsigned long)(org0), org - org0);
 624         }
 625         *ppos += written;
 626         ret = written;
 627         if (written)
 628                 vcs_scr_updated(vc);
 629
 630 unlock_out:
 631         console_unlock();
 632         free_page((unsigned long) con_buf);
 633         return ret;
 634 }
 635
 636 static __poll_t
 637 vcs_poll(struct file *file, poll_table *wait)
 638 {
 639         struct vcs_poll_data *poll = vcs_poll_data_get(file);
 640         __poll_t ret = DEFAULT_POLLMASK|EPOLLERR|EPOLLPRI;
 641
 642         if (poll) {
 643                 poll_wait(file, &poll->waitq, wait);
 644                 if (poll->seen_last_update)
 645                         ret = DEFAULT_POLLMASK;
 646         }
 647         return ret;
 648 }
 649
 650 static int
 651 vcs_fasync(int fd, struct file *file, int on)
 652 {
 653         struct vcs_poll_data *poll = file->private_data;
 654
 655         if (!poll) {
 656                 /* don't allocate anything if all we want is disable fasync */
 657                 if (!on)
 658                         return 0;
 659                 poll = vcs_poll_data_get(file);
 660                 if (!poll)
 661                         return -ENOMEM;
 662         }
 663
 664         return fasync_helper(fd, file, on, &poll->fasync);
 665 }
 666
 667 static int
 668 vcs_open(struct inode *inode, struct file *filp)
 669 {
 670         unsigned int currcons = console(inode);
 671         bool attr = use_attributes(inode);
 672         bool uni_mode = use_unicode(inode);
 673         int ret = 0;
 674
 675         /* we currently don't support attributes in unicode mode */
 676         if (attr && uni_mode)
 677                 return -EOPNOTSUPP;
 678
 679         console_lock();
 680         if(currcons && !vc_cons_allocated(currcons-1))
 681                 ret = -ENXIO;
 682         console_unlock();
 683         return ret;
 684 }
 685
 686 static int vcs_release(struct inode *inode, struct file *file)
 687 {
 688         struct vcs_poll_data *poll = file->private_data;
 689
 690         if (poll)
 691                 vcs_poll_data_free(poll);
 692         return 0;
 693 }
 694
 695 static const struct file_operations vcs_fops = {
 696         .llseek         = vcs_lseek,
 697         .read           = vcs_read,
 698         .write          = vcs_write,
 699         .poll           = vcs_poll,
 700         .fasync         = vcs_fasync,
 701         .open           = vcs_open,
 702         .release        = vcs_release,
 703 };
 704
 705 static struct class *vc_class;
 706
 707 void vcs_make_sysfs(int index)
 708 {
 709         device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 1), NULL,
 710                       "vcs%u", index + 1);
 711         device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 65), NULL,
 712                       "vcsu%u", index + 1);
 713         device_create(vc_class, NULL, MKDEV(VCS_MAJOR, index + 129), NULL,
 714                       "vcsa%u", index + 1);
 715 }
 716
 717 void vcs_remove_sysfs(int index)
 718 {
 719         device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 1));
 720         device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 65));
 721         device_destroy(vc_class, MKDEV(VCS_MAJOR, index + 129));
 722 }
 723
 724 int __init vcs_init(void)
 725 {
 726         unsigned int i;
 727
 728         if (register_chrdev(VCS_MAJOR, "vcs", &vcs_fops))
 729                 panic("unable to get major %d for vcs device", VCS_MAJOR);
 730         vc_class = class_create(THIS_MODULE, "vc");
 731
 732         device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 0), NULL, "vcs");
 733         device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 64), NULL, "vcsu");
 734         device_create(vc_class, NULL, MKDEV(VCS_MAJOR, 128), NULL, "vcsa");
 735         for (i = 0; i < MIN_NR_CONSOLES; i++)
 736                 vcs_make_sysfs(i);
 737         return 0;
 738 }