drivers/tty/vt/vt.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  Copyright (C) 1991, 1992  Linus Torvalds
   4  */
   5
   6 /*
   7  * Hopefully this will be a rather complete VT102 implementation.
   8  *
   9  * Beeping thanks to John T Kohl.
  10  *
  11  * Virtual Consoles, Screen Blanking, Screen Dumping, Color, Graphics
  12  *   Chars, and VT100 enhancements by Peter MacDonald.
  13  *
  14  * Copy and paste function by Andrew Haylett,
  15  *   some enhancements by Alessandro Rubini.
  16  *
  17  * Code to check for different video-cards mostly by Galen Hunt,
  18  * <g-hunt@ee.utah.edu>
  19  *
  20  * Rudimentary ISO 10646/Unicode/UTF-8 character set support by
  21  * Markus Kuhn, <mskuhn@immd4.informatik.uni-erlangen.de>.
  22  *
  23  * Dynamic allocation of consoles, aeb@cwi.nl, May 1994
  24  * Resizing of consoles, aeb, 940926
  25  *
  26  * Code for xterm like mouse click reporting by Peter Orbaek 20-Jul-94
  27  * <poe@daimi.aau.dk>
  28  *
  29  * User-defined bell sound, new setterm control sequences and printk
  30  * redirection by Martin Mares <mj@k332.feld.cvut.cz> 19-Nov-95
  31  *
  32  * APM screenblank bug fixed Takashi Manabe <manabe@roy.dsl.tutics.tut.jp>
  33  *
  34  * Merge with the abstract console driver by Geert Uytterhoeven
  35  * <geert@linux-m68k.org>, Jan 1997.
  36  *
  37  *   Original m68k console driver modifications by
  38  *
  39  *     - Arno Griffioen <arno@usn.nl>
  40  *     - David Carter <carter@cs.bris.ac.uk>
  41  *
  42  *   The abstract console driver provides a generic interface for a text
  43  *   console. It supports VGA text mode, frame buffer based graphical consoles
  44  *   and special graphics processors that are only accessible through some
  45  *   registers (e.g. a TMS340x0 GSP).
  46  *
  47  *   The interface to the hardware is specified using a special structure
  48  *   (struct consw) which contains function pointers to console operations
  49  *   (see <linux/console.h> for more information).
  50  *
  51  * Support for changeable cursor shape
  52  * by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz>, August 1997
  53  *
  54  * Ported to i386 and con_scrolldelta fixed
  55  * by Emmanuel Marty <core@ggi-project.org>, April 1998
  56  *
  57  * Resurrected character buffers in videoram plus lots of other trickery
  58  * by Martin Mares <mj@atrey.karlin.mff.cuni.cz>, July 1998
  59  *
  60  * Removed old-style timers, introduced console_timer, made timer
  61  * deletion SMP-safe.  17Jun00, Andrew Morton
  62  *
  63  * Removed console_lock, enabled interrupts across all console operations
  64  * 13 March 2001, Andrew Morton
  65  *
  66  * Fixed UTF-8 mode so alternate charset modes always work according
  67  * to control sequences interpreted in do_con_trol function
  68  * preserving backward VT100 semigraphics compatibility,
  69  * malformed UTF sequences represented as sequences of replacement glyphs,
  70  * original codes or '?' as a last resort if replacement glyph is undefined
  71  * by Adam Tla/lka <atlka@pg.gda.pl>, Aug 2006
  72  */
  73
  74 #include <linux/module.h>
  75 #include <linux/types.h>
  76 #include <linux/sched/signal.h>
  77 #include <linux/tty.h>
  78 #include <linux/tty_flip.h>
  79 #include <linux/kernel.h>
  80 #include <linux/string.h>
  81 #include <linux/errno.h>
  82 #include <linux/kd.h>
  83 #include <linux/slab.h>
  84 #include <linux/major.h>
  85 #include <linux/mm.h>
  86 #include <linux/console.h>
  87 #include <linux/init.h>
  88 #include <linux/mutex.h>
  89 #include <linux/vt_kern.h>
  90 #include <linux/selection.h>
  91 #include <linux/tiocl.h>
  92 #include <linux/kbd_kern.h>
  93 #include <linux/consolemap.h>
  94 #include <linux/timer.h>
  95 #include <linux/interrupt.h>
  96 #include <linux/workqueue.h>
  97 #include <linux/pm.h>
  98 #include <linux/font.h>
  99 #include <linux/bitops.h>
 100 #include <linux/notifier.h>
 101 #include <linux/device.h>
 102 #include <linux/io.h>
 103 #include <linux/uaccess.h>
 104 #include <linux/kdb.h>
 105 #include <linux/ctype.h>
 106 #include <linux/bsearch.h>
 107 #include <linux/gcd.h>
 108
 109 #define MAX_NR_CON_DRIVER 16
 110
 111 #define CON_DRIVER_FLAG_MODULE 1
 112 #define CON_DRIVER_FLAG_INIT   2
 113 #define CON_DRIVER_FLAG_ATTR   4
 114 #define CON_DRIVER_FLAG_ZOMBIE 8
 115
 116 struct con_driver {
 117         const struct consw *con;
 118         const char *desc;
 119         struct device *dev;
 120         int node;
 121         int first;
 122         int last;
 123         int flag;
 124 };
 125
 126 static struct con_driver registered_con_driver[MAX_NR_CON_DRIVER];
 127 const struct consw *conswitchp;
 128
 129 /* A bitmap for codes <32. A bit of 1 indicates that the code
 130  * corresponding to that bit number invokes some special action
 131  * (such as cursor movement) and should not be displayed as a
 132  * glyph unless the disp_ctrl mode is explicitly enabled.
 133  */
 134 #define CTRL_ACTION 0x0d00ff81
 135 #define CTRL_ALWAYS 0x0800f501  /* Cannot be overridden by disp_ctrl */
 136
 137 /*
 138  * Here is the default bell parameters: 750HZ, 1/8th of a second
 139  */
 140 #define DEFAULT_BELL_PITCH      750
 141 #define DEFAULT_BELL_DURATION   (HZ/8)
 142 #define DEFAULT_CURSOR_BLINK_MS 200
 143
 144 struct vc vc_cons [MAX_NR_CONSOLES];
 145
 146 #ifndef VT_SINGLE_DRIVER
 147 static const struct consw *con_driver_map[MAX_NR_CONSOLES];
 148 #endif
 149
 150 static int con_open(struct tty_struct *, struct file *);
 151 static void vc_init(struct vc_data *vc, unsigned int rows,
 152                     unsigned int cols, int do_clear);
 153 static void gotoxy(struct vc_data *vc, int new_x, int new_y);
 154 static void save_cur(struct vc_data *vc);
 155 static void reset_terminal(struct vc_data *vc, int do_clear);
 156 static void con_flush_chars(struct tty_struct *tty);
 157 static int set_vesa_blanking(char __user *p);
 158 static void set_cursor(struct vc_data *vc);
 159 static void hide_cursor(struct vc_data *vc);
 160 static void console_callback(struct work_struct *ignored);
 161 static void con_driver_unregister_callback(struct work_struct *ignored);
 162 static void blank_screen_t(struct timer_list *unused);
 163 static void set_palette(struct vc_data *vc);
 164
 165 #define vt_get_kmsg_redirect() vt_kmsg_redirect(-1)
 166
 167 static int printable;           /* Is console ready for printing? */
 168 int default_utf8 = true;
 169 module_param(default_utf8, int, S_IRUGO | S_IWUSR);
 170 int global_cursor_default = -1;
 171 module_param(global_cursor_default, int, S_IRUGO | S_IWUSR);
 172
 173 static int cur_default = CUR_DEFAULT;
 174 module_param(cur_default, int, S_IRUGO | S_IWUSR);
 175
 176 /*
 177  * ignore_poke: don't unblank the screen when things are typed.  This is
 178  * mainly for the privacy of braille terminal users.
 179  */
 180 static int ignore_poke;
 181
 182 int do_poke_blanked_console;
 183 int console_blanked;
 184
 185 static int vesa_blank_mode; /* 0:none 1:suspendV 2:suspendH 3:powerdown */
 186 static int vesa_off_interval;
 187 static int blankinterval;
 188 core_param(consoleblank, blankinterval, int, 0444);
 189
 190 static DECLARE_WORK(console_work, console_callback);
 191 static DECLARE_WORK(con_driver_unregister_work, con_driver_unregister_callback);
 192
 193 /*
 194  * fg_console is the current virtual console,
 195  * last_console is the last used one,
 196  * want_console is the console we want to switch to,
 197  * saved_* variants are for save/restore around kernel debugger enter/leave
 198  */
 199 int fg_console;
 200 int last_console;
 201 int want_console = -1;
 202 static int saved_fg_console;
 203 static int saved_last_console;
 204 static int saved_want_console;
 205 static int saved_vc_mode;
 206 static int saved_console_blanked;
 207
 208 /*
 209  * For each existing display, we have a pointer to console currently visible
 210  * on that display, allowing consoles other than fg_console to be refreshed
 211  * appropriately. Unless the low-level driver supplies its own display_fg
 212  * variable, we use this one for the "master display".
 213  */
 214 static struct vc_data *master_display_fg;
 215
 216 /*
 217  * Unfortunately, we need to delay tty echo when we're currently writing to the
 218  * console since the code is (and always was) not re-entrant, so we schedule
 219  * all flip requests to process context with schedule-task() and run it from
 220  * console_callback().
 221  */
 222
 223 /*
 224  * For the same reason, we defer scrollback to the console callback.
 225  */
 226 static int scrollback_delta;
 227
 228 /*
 229  * Hook so that the power management routines can (un)blank
 230  * the console on our behalf.
 231  */
 232 int (*console_blank_hook)(int);
 233
 234 static DEFINE_TIMER(console_timer, blank_screen_t);
 235 static int blank_state;
 236 static int blank_timer_expired;
 237 enum {
 238         blank_off = 0,
 239         blank_normal_wait,
 240         blank_vesa_wait,
 241 };
 242
 243 /*
 244  * /sys/class/tty/tty0/
 245  *
 246  * the attribute 'active' contains the name of the current vc
 247  * console and it supports poll() to detect vc switches
 248  */
 249 static struct device *tty0dev;
 250
 251 /*
 252  * Notifier list for console events.
 253  */
 254 static ATOMIC_NOTIFIER_HEAD(vt_notifier_list);
 255
 256 int register_vt_notifier(struct notifier_block *nb)
 257 {
 258         return atomic_notifier_chain_register(&vt_notifier_list, nb);
 259 }
 260 EXPORT_SYMBOL_GPL(register_vt_notifier);
 261
 262 int unregister_vt_notifier(struct notifier_block *nb)
 263 {
 264         return atomic_notifier_chain_unregister(&vt_notifier_list, nb);
 265 }
 266 EXPORT_SYMBOL_GPL(unregister_vt_notifier);
 267
 268 static void notify_write(struct vc_data *vc, unsigned int unicode)
 269 {
 270         struct vt_notifier_param param = { .vc = vc, .c = unicode };
 271         atomic_notifier_call_chain(&vt_notifier_list, VT_WRITE, &param);
 272 }
 273
 274 static void notify_update(struct vc_data *vc)
 275 {
 276         struct vt_notifier_param param = { .vc = vc };
 277         atomic_notifier_call_chain(&vt_notifier_list, VT_UPDATE, &param);
 278 }
 279 /*
 280  *      Low-Level Functions
 281  */
 282
 283 static inline bool con_is_fg(const struct vc_data *vc)
 284 {
 285         return vc->vc_num == fg_console;
 286 }
 287
 288 static inline bool con_should_update(const struct vc_data *vc)
 289 {
 290         return con_is_visible(vc) && !console_blanked;
 291 }
 292
 293 static inline unsigned short *screenpos(struct vc_data *vc, int offset, int viewed)
 294 {
 295         unsigned short *p;
 296
 297         if (!viewed)
 298                 p = (unsigned short *)(vc->vc_origin + offset);
 299         else if (!vc->vc_sw->con_screen_pos)
 300                 p = (unsigned short *)(vc->vc_visible_origin + offset);
 301         else
 302                 p = vc->vc_sw->con_screen_pos(vc, offset);
 303         return p;
 304 }
 305
 306 /* Called  from the keyboard irq path.. */
 307 static inline void scrolldelta(int lines)
 308 {
 309         /* FIXME */
 310         /* scrolldelta needs some kind of consistency lock, but the BKL was
 311            and still is not protecting versus the scheduled back end */
 312         scrollback_delta += lines;
 313         schedule_console_callback();
 314 }
 315
 316 void schedule_console_callback(void)
 317 {
 318         schedule_work(&console_work);
 319 }
 320
 321 /*
 322  * Code to manage unicode-based screen buffers
 323  */
 324
 325 #ifdef NO_VC_UNI_SCREEN
 326 /* this disables and optimizes related code away at compile time */
 327 #define get_vc_uniscr(vc) NULL
 328 #else
 329 #define get_vc_uniscr(vc) vc->vc_uni_screen
 330 #endif
 331
 332 #define VC_UNI_SCREEN_DEBUG 0
 333
 334 typedef uint32_t char32_t;
 335
 336 /*
 337  * Our screen buffer is preceded by an array of line pointers so that
 338  * scrolling only implies some pointer shuffling.
 339  */
 340 struct uni_screen {
 341         char32_t *lines[0];
 342 };
 343
 344 static struct uni_screen *vc_uniscr_alloc(unsigned int cols, unsigned int rows)
 345 {
 346         struct uni_screen *uniscr;
 347         void *p;
 348         unsigned int memsize, i;
 349
 350         /* allocate everything in one go */
 351         memsize = cols * rows * sizeof(char32_t);
 352         memsize += rows * sizeof(char32_t *);
 353         p = kmalloc(memsize, GFP_KERNEL);
 354         if (!p)
 355                 return NULL;
 356
 357         /* initial line pointers */
 358         uniscr = p;
 359         p = uniscr->lines + rows;
 360         for (i = 0; i < rows; i++) {
 361                 uniscr->lines[i] = p;
 362                 p += cols * sizeof(char32_t);
 363         }
 364         return uniscr;
 365 }
 366
 367 static void vc_uniscr_set(struct vc_data *vc, struct uni_screen *new_uniscr)
 368 {
 369         kfree(vc->vc_uni_screen);
 370         vc->vc_uni_screen = new_uniscr;
 371 }
 372
 373 static void vc_uniscr_putc(struct vc_data *vc, char32_t uc)
 374 {
 375         struct uni_screen *uniscr = get_vc_uniscr(vc);
 376
 377         if (uniscr)
 378                 uniscr->lines[vc->vc_y][vc->vc_x] = uc;
 379 }
 380
 381 static void vc_uniscr_insert(struct vc_data *vc, unsigned int nr)
 382 {
 383         struct uni_screen *uniscr = get_vc_uniscr(vc);
 384
 385         if (uniscr) {
 386                 char32_t *ln = uniscr->lines[vc->vc_y];
 387                 unsigned int x = vc->vc_x, cols = vc->vc_cols;
 388
 389                 memmove(&ln[x + nr], &ln[x], (cols - x - nr) * sizeof(*ln));
 390                 memset32(&ln[x], ' ', nr);
 391         }
 392 }
 393
 394 static void vc_uniscr_delete(struct vc_data *vc, unsigned int nr)
 395 {
 396         struct uni_screen *uniscr = get_vc_uniscr(vc);
 397
 398         if (uniscr) {
 399                 char32_t *ln = uniscr->lines[vc->vc_y];
 400                 unsigned int x = vc->vc_x, cols = vc->vc_cols;
 401
 402                 memcpy(&ln[x], &ln[x + nr], (cols - x - nr) * sizeof(*ln));
 403                 memset32(&ln[cols - nr], ' ', nr);
 404         }
 405 }
 406
 407 static void vc_uniscr_clear_line(struct vc_data *vc, unsigned int x,
 408                                  unsigned int nr)
 409 {
 410         struct uni_screen *uniscr = get_vc_uniscr(vc);
 411
 412         if (uniscr) {
 413                 char32_t *ln = uniscr->lines[vc->vc_y];
 414
 415                 memset32(&ln[x], ' ', nr);
 416         }
 417 }
 418
 419 static void vc_uniscr_clear_lines(struct vc_data *vc, unsigned int y,
 420                                   unsigned int nr)
 421 {
 422         struct uni_screen *uniscr = get_vc_uniscr(vc);
 423
 424         if (uniscr) {
 425                 unsigned int cols = vc->vc_cols;
 426
 427                 while (nr--)
 428                         memset32(uniscr->lines[y++], ' ', cols);
 429         }
 430 }
 431
 432 static void vc_uniscr_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
 433                              enum con_scroll dir, unsigned int nr)
 434 {
 435         struct uni_screen *uniscr = get_vc_uniscr(vc);
 436
 437         if (uniscr) {
 438                 unsigned int i, j, k, sz, d, clear;
 439
 440                 sz = b - t;
 441                 clear = b - nr;
 442                 d = nr;
 443                 if (dir == SM_DOWN) {
 444                         clear = t;
 445                         d = sz - nr;
 446                 }
 447                 for (i = 0; i < gcd(d, sz); i++) {
 448                         char32_t *tmp = uniscr->lines[t + i];
 449                         j = i;
 450                         while (1) {
 451                                 k = j + d;
 452                                 if (k >= sz)
 453                                         k -= sz;
 454                                 if (k == i)
 455                                         break;
 456                                 uniscr->lines[t + j] = uniscr->lines[t + k];
 457                                 j = k;
 458                         }
 459                         uniscr->lines[t + j] = tmp;
 460                 }
 461                 vc_uniscr_clear_lines(vc, clear, nr);
 462         }
 463 }
 464
 465 static void vc_uniscr_copy_area(struct uni_screen *dst,
 466                                 unsigned int dst_cols,
 467                                 unsigned int dst_rows,
 468                                 struct uni_screen *src,
 469                                 unsigned int src_cols,
 470                                 unsigned int src_top_row,
 471                                 unsigned int src_bot_row)
 472 {
 473         unsigned int dst_row = 0;
 474
 475         if (!dst)
 476                 return;
 477
 478         while (src_top_row < src_bot_row) {
 479                 char32_t *src_line = src->lines[src_top_row];
 480                 char32_t *dst_line = dst->lines[dst_row];
 481
 482                 memcpy(dst_line, src_line, src_cols * sizeof(char32_t));
 483                 if (dst_cols - src_cols)
 484                         memset32(dst_line + src_cols, ' ', dst_cols - src_cols);
 485                 src_top_row++;
 486                 dst_row++;
 487         }
 488         while (dst_row < dst_rows) {
 489                 char32_t *dst_line = dst->lines[dst_row];
 490
 491                 memset32(dst_line, ' ', dst_cols);
 492                 dst_row++;
 493         }
 494 }
 495
 496 /*
 497  * Called from vcs_read() to make sure unicode screen retrieval is possible.
 498  * This will initialize the unicode screen buffer if not already done.
 499  * This returns 0 if OK, or a negative error code otherwise.
 500  * In particular, -ENODATA is returned if the console is not in UTF-8 mode.
 501  */
 502 int vc_uniscr_check(struct vc_data *vc)
 503 {
 504         struct uni_screen *uniscr;
 505         unsigned short *p;
 506         int x, y, mask;
 507
 508         if (__is_defined(NO_VC_UNI_SCREEN))
 509                 return -EOPNOTSUPP;
 510
 511         WARN_CONSOLE_UNLOCKED();
 512
 513         if (!vc->vc_utf)
 514                 return -ENODATA;
 515
 516         if (vc->vc_uni_screen)
 517                 return 0;
 518
 519         uniscr = vc_uniscr_alloc(vc->vc_cols, vc->vc_rows);
 520         if (!uniscr)
 521                 return -ENOMEM;
 522
 523         /*
 524          * Let's populate it initially with (imperfect) reverse translation.
 525          * This is the next best thing we can do short of having it enabled
 526          * from the start even when no users rely on this functionality. True
 527          * unicode content will be available after a complete screen refresh.
 528          */
 529         p = (unsigned short *)vc->vc_origin;
 530         mask = vc->vc_hi_font_mask | 0xff;
 531         for (y = 0; y < vc->vc_rows; y++) {
 532                 char32_t *line = uniscr->lines[y];
 533                 for (x = 0; x < vc->vc_cols; x++) {
 534                         u16 glyph = scr_readw(p++) & mask;
 535                         line[x] = inverse_translate(vc, glyph, true);
 536                 }
 537         }
 538
 539         vc->vc_uni_screen = uniscr;
 540         return 0;
 541 }
 542
 543 /*
 544  * Called from vcs_read() to get the unicode data from the screen.
 545  * This must be preceded by a successful call to vc_uniscr_check() once
 546  * the console lock has been taken.
 547  */
 548 void vc_uniscr_copy_line(struct vc_data *vc, void *dest, int viewed,
 549                          unsigned int row, unsigned int col, unsigned int nr)
 550 {
 551         struct uni_screen *uniscr = get_vc_uniscr(vc);
 552         int offset = row * vc->vc_size_row + col * 2;
 553         unsigned long pos;
 554
 555         BUG_ON(!uniscr);
 556
 557         pos = (unsigned long)screenpos(vc, offset, viewed);
 558         if (pos >= vc->vc_origin && pos < vc->vc_scr_end) {
 559                 /*
 560                  * Desired position falls in the main screen buffer.
 561                  * However the actual row/col might be different if
 562                  * scrollback is active.
 563                  */
 564                 row = (pos - vc->vc_origin) / vc->vc_size_row;
 565                 col = ((pos - vc->vc_origin) % vc->vc_size_row) / 2;
 566                 memcpy(dest, &uniscr->lines[row][col], nr * sizeof(char32_t));
 567         } else {
 568                 /*
 569                  * Scrollback is active. For now let's simply backtranslate
 570                  * the screen glyphs until the unicode screen buffer does
 571                  * synchronize with console display drivers for a scrollback
 572                  * buffer of its own.
 573                  */
 574                 u16 *p = (u16 *)pos;
 575                 int mask = vc->vc_hi_font_mask | 0xff;
 576                 char32_t *uni_buf = dest;
 577                 while (nr--) {
 578                         u16 glyph = scr_readw(p++) & mask;
 579                         *uni_buf++ = inverse_translate(vc, glyph, true);
 580                 }
 581         }
 582 }
 583
 584 /* this is for validation and debugging only */
 585 static void vc_uniscr_debug_check(struct vc_data *vc)
 586 {
 587         struct uni_screen *uniscr = get_vc_uniscr(vc);
 588         unsigned short *p;
 589         int x, y, mask;
 590
 591         if (!VC_UNI_SCREEN_DEBUG || !uniscr)
 592                 return;
 593
 594         WARN_CONSOLE_UNLOCKED();
 595
 596         /*
 597          * Make sure our unicode screen translates into the same glyphs
 598          * as the actual screen. This is brutal indeed.
 599          */
 600         p = (unsigned short *)vc->vc_origin;
 601         mask = vc->vc_hi_font_mask | 0xff;
 602         for (y = 0; y < vc->vc_rows; y++) {
 603                 char32_t *line = uniscr->lines[y];
 604                 for (x = 0; x < vc->vc_cols; x++) {
 605                         u16 glyph = scr_readw(p++) & mask;
 606                         char32_t uc = line[x];
 607                         int tc = conv_uni_to_pc(vc, uc);
 608                         if (tc == -4)
 609                                 tc = conv_uni_to_pc(vc, 0xfffd);
 610                         if (tc == -4)
 611                                 tc = conv_uni_to_pc(vc, '?');
 612                         if (tc != glyph)
 613                                 pr_err_ratelimited(
 614                                         "%s: mismatch at %d,%d: glyph=%#x tc=%#x\n",
 615                                         __func__, x, y, glyph, tc);
 616                 }
 617         }
 618 }
 619
 620
 621 static void con_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
 622                 enum con_scroll dir, unsigned int nr)
 623 {
 624         u16 *clear, *d, *s;
 625
 626         if (t + nr >= b)
 627                 nr = b - t - 1;
 628         if (b > vc->vc_rows || t >= b || nr < 1)
 629                 return;
 630         vc_uniscr_scroll(vc, t, b, dir, nr);
 631         if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, t, b, dir, nr))
 632                 return;
 633
 634         s = clear = (u16 *)(vc->vc_origin + vc->vc_size_row * t);
 635         d = (u16 *)(vc->vc_origin + vc->vc_size_row * (t + nr));
 636
 637         if (dir == SM_UP) {
 638                 clear = s + (b - t - nr) * vc->vc_cols;
 639                 swap(s, d);
 640         }
 641         scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
 642         scr_memsetw(clear, vc->vc_video_erase_char, vc->vc_size_row * nr);
 643 }
 644
 645 static void do_update_region(struct vc_data *vc, unsigned long start, int count)
 646 {
 647         unsigned int xx, yy, offset;
 648         u16 *p;
 649
 650         p = (u16 *) start;
 651         if (!vc->vc_sw->con_getxy) {
 652                 offset = (start - vc->vc_origin) / 2;
 653                 xx = offset % vc->vc_cols;
 654                 yy = offset / vc->vc_cols;
 655         } else {
 656                 int nxx, nyy;
 657                 start = vc->vc_sw->con_getxy(vc, start, &nxx, &nyy);
 658                 xx = nxx; yy = nyy;
 659         }
 660         for(;;) {
 661                 u16 attrib = scr_readw(p) & 0xff00;
 662                 int startx = xx;
 663                 u16 *q = p;
 664                 while (xx < vc->vc_cols && count) {
 665                         if (attrib != (scr_readw(p) & 0xff00)) {
 666                                 if (p > q)
 667                                         vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
 668                                 startx = xx;
 669                                 q = p;
 670                                 attrib = scr_readw(p) & 0xff00;
 671                         }
 672                         p++;
 673                         xx++;
 674                         count--;
 675                 }
 676                 if (p > q)
 677                         vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
 678                 if (!count)
 679                         break;
 680                 xx = 0;
 681                 yy++;
 682                 if (vc->vc_sw->con_getxy) {
 683                         p = (u16 *)start;
 684                         start = vc->vc_sw->con_getxy(vc, start, NULL, NULL);
 685                 }
 686         }
 687 }
 688
 689 void update_region(struct vc_data *vc, unsigned long start, int count)
 690 {
 691         WARN_CONSOLE_UNLOCKED();
 692
 693         if (con_should_update(vc)) {
 694                 hide_cursor(vc);
 695                 do_update_region(vc, start, count);
 696                 set_cursor(vc);
 697         }
 698 }
 699
 700 /* Structure of attributes is hardware-dependent */
 701
 702 static u8 build_attr(struct vc_data *vc, u8 _color, u8 _intensity, u8 _blink,
 703     u8 _underline, u8 _reverse, u8 _italic)
 704 {
 705         if (vc->vc_sw->con_build_attr)
 706                 return vc->vc_sw->con_build_attr(vc, _color, _intensity,
 707                        _blink, _underline, _reverse, _italic);
 708
 709 /*
 710  * ++roman: I completely changed the attribute format for monochrome
 711  * mode (!can_do_color). The formerly used MDA (monochrome display
 712  * adapter) format didn't allow the combination of certain effects.
 713  * Now the attribute is just a bit vector:
 714  *  Bit 0..1: intensity (0..2)
 715  *  Bit 2   : underline
 716  *  Bit 3   : reverse
 717  *  Bit 7   : blink
 718  */
 719         {
 720         u8 a = _color;
 721         if (!vc->vc_can_do_color)
 722                 return _intensity |
 723                        (_italic ? 2 : 0) |
 724                        (_underline ? 4 : 0) |
 725                        (_reverse ? 8 : 0) |
 726                        (_blink ? 0x80 : 0);
 727         if (_italic)
 728                 a = (a & 0xF0) | vc->vc_itcolor;
 729         else if (_underline)
 730                 a = (a & 0xf0) | vc->vc_ulcolor;
 731         else if (_intensity == 0)
 732                 a = (a & 0xf0) | vc->vc_halfcolor;
 733         if (_reverse)
 734                 a = ((a) & 0x88) | ((((a) >> 4) | ((a) << 4)) & 0x77);
 735         if (_blink)
 736                 a ^= 0x80;
 737         if (_intensity == 2)
 738                 a ^= 0x08;
 739         if (vc->vc_hi_font_mask == 0x100)
 740                 a <<= 1;
 741         return a;
 742         }
 743 }
 744
 745 static void update_attr(struct vc_data *vc)
 746 {
 747         vc->vc_attr = build_attr(vc, vc->vc_color, vc->vc_intensity,
 748                       vc->vc_blink, vc->vc_underline,
 749                       vc->vc_reverse ^ vc->vc_decscnm, vc->vc_italic);
 750         vc->vc_video_erase_char = (build_attr(vc, vc->vc_color, 1, vc->vc_blink, 0, vc->vc_decscnm, 0) << 8) | ' ';
 751 }
 752
 753 /* Note: inverting the screen twice should revert to the original state */
 754 void invert_screen(struct vc_data *vc, int offset, int count, int viewed)
 755 {
 756         unsigned short *p;
 757
 758         WARN_CONSOLE_UNLOCKED();
 759
 760         count /= 2;
 761         p = screenpos(vc, offset, viewed);
 762         if (vc->vc_sw->con_invert_region) {
 763                 vc->vc_sw->con_invert_region(vc, p, count);
 764         } else {
 765                 u16 *q = p;
 766                 int cnt = count;
 767                 u16 a;
 768
 769                 if (!vc->vc_can_do_color) {
 770                         while (cnt--) {
 771                             a = scr_readw(q);
 772                             a ^= 0x0800;
 773                             scr_writew(a, q);
 774                             q++;
 775                         }
 776                 } else if (vc->vc_hi_font_mask == 0x100) {
 777                         while (cnt--) {
 778                                 a = scr_readw(q);
 779                                 a = ((a) & 0x11ff) | (((a) & 0xe000) >> 4) | (((a) & 0x0e00) << 4);
 780                                 scr_writew(a, q);
 781                                 q++;
 782                         }
 783                 } else {
 784                         while (cnt--) {
 785                                 a = scr_readw(q);
 786                                 a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) | (((a) & 0x0700) << 4);
 787                                 scr_writew(a, q);
 788                                 q++;
 789                         }
 790                 }
 791         }
 792
 793         if (con_should_update(vc))
 794                 do_update_region(vc, (unsigned long) p, count);
 795         notify_update(vc);
 796 }
 797
 798 /* used by selection: complement pointer position */
 799 void complement_pos(struct vc_data *vc, int offset)
 800 {
 801         static int old_offset = -1;
 802         static unsigned short old;
 803         static unsigned short oldx, oldy;
 804
 805         WARN_CONSOLE_UNLOCKED();
 806
 807         if (old_offset != -1 && old_offset >= 0 &&
 808             old_offset < vc->vc_screenbuf_size) {
 809                 scr_writew(old, screenpos(vc, old_offset, 1));
 810                 if (con_should_update(vc))
 811                         vc->vc_sw->con_putc(vc, old, oldy, oldx);
 812                 notify_update(vc);
 813         }
 814
 815         old_offset = offset;
 816
 817         if (offset != -1 && offset >= 0 &&
 818             offset < vc->vc_screenbuf_size) {
 819                 unsigned short new;
 820                 unsigned short *p;
 821                 p = screenpos(vc, offset, 1);
 822                 old = scr_readw(p);
 823                 new = old ^ vc->vc_complement_mask;
 824                 scr_writew(new, p);
 825                 if (con_should_update(vc)) {
 826                         oldx = (offset >> 1) % vc->vc_cols;
 827                         oldy = (offset >> 1) / vc->vc_cols;
 828                         vc->vc_sw->con_putc(vc, new, oldy, oldx);
 829                 }
 830                 notify_update(vc);
 831         }
 832 }
 833
 834 static void insert_char(struct vc_data *vc, unsigned int nr)
 835 {
 836         unsigned short *p = (unsigned short *) vc->vc_pos;
 837
 838         vc_uniscr_insert(vc, nr);
 839         scr_memmovew(p + nr, p, (vc->vc_cols - vc->vc_x - nr) * 2);
 840         scr_memsetw(p, vc->vc_video_erase_char, nr * 2);
 841         vc->vc_need_wrap = 0;
 842         if (con_should_update(vc))
 843                 do_update_region(vc, (unsigned long) p,
 844                         vc->vc_cols - vc->vc_x);
 845 }
 846
 847 static void delete_char(struct vc_data *vc, unsigned int nr)
 848 {
 849         unsigned short *p = (unsigned short *) vc->vc_pos;
 850
 851         vc_uniscr_delete(vc, nr);
 852         scr_memcpyw(p, p + nr, (vc->vc_cols - vc->vc_x - nr) * 2);
 853         scr_memsetw(p + vc->vc_cols - vc->vc_x - nr, vc->vc_video_erase_char,
 854                         nr * 2);
 855         vc->vc_need_wrap = 0;
 856         if (con_should_update(vc))
 857                 do_update_region(vc, (unsigned long) p,
 858                         vc->vc_cols - vc->vc_x);
 859 }
 860
 861 static int softcursor_original = -1;
 862
 863 static void add_softcursor(struct vc_data *vc)
 864 {
 865         int i = scr_readw((u16 *) vc->vc_pos);
 866         u32 type = vc->vc_cursor_type;
 867
 868         if (! (type & 0x10)) return;
 869         if (softcursor_original != -1) return;
 870         softcursor_original = i;
 871         i |= ((type >> 8) & 0xff00 );
 872         i ^= ((type) & 0xff00 );
 873         if ((type & 0x20) && ((softcursor_original & 0x7000) == (i & 0x7000))) i ^= 0x7000;
 874         if ((type & 0x40) && ((i & 0x700) == ((i & 0x7000) >> 4))) i ^= 0x0700;
 875         scr_writew(i, (u16 *) vc->vc_pos);
 876         if (con_should_update(vc))
 877                 vc->vc_sw->con_putc(vc, i, vc->vc_y, vc->vc_x);
 878 }
 879
 880 static void hide_softcursor(struct vc_data *vc)
 881 {
 882         if (softcursor_original != -1) {
 883                 scr_writew(softcursor_original, (u16 *)vc->vc_pos);
 884                 if (con_should_update(vc))
 885                         vc->vc_sw->con_putc(vc, softcursor_original,
 886                                         vc->vc_y, vc->vc_x);
 887                 softcursor_original = -1;
 888         }
 889 }
 890
 891 static void hide_cursor(struct vc_data *vc)
 892 {
 893         if (vc == sel_cons)
 894                 clear_selection();
 895         vc->vc_sw->con_cursor(vc, CM_ERASE);
 896         hide_softcursor(vc);
 897 }
 898
 899 static void set_cursor(struct vc_data *vc)
 900 {
 901         if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS)
 902                 return;
 903         if (vc->vc_deccm) {
 904                 if (vc == sel_cons)
 905                         clear_selection();
 906                 add_softcursor(vc);
 907                 if ((vc->vc_cursor_type & 0x0f) != 1)
 908                         vc->vc_sw->con_cursor(vc, CM_DRAW);
 909         } else
 910                 hide_cursor(vc);
 911 }
 912
 913 static void set_origin(struct vc_data *vc)
 914 {
 915         WARN_CONSOLE_UNLOCKED();
 916
 917         if (!con_is_visible(vc) ||
 918             !vc->vc_sw->con_set_origin ||
 919             !vc->vc_sw->con_set_origin(vc))
 920                 vc->vc_origin = (unsigned long)vc->vc_screenbuf;
 921         vc->vc_visible_origin = vc->vc_origin;
 922         vc->vc_scr_end = vc->vc_origin + vc->vc_screenbuf_size;
 923         vc->vc_pos = vc->vc_origin + vc->vc_size_row * vc->vc_y + 2 * vc->vc_x;
 924 }
 925
 926 static void save_screen(struct vc_data *vc)
 927 {
 928         WARN_CONSOLE_UNLOCKED();
 929
 930         if (vc->vc_sw->con_save_screen)
 931                 vc->vc_sw->con_save_screen(vc);
 932 }
 933
 934 static void flush_scrollback(struct vc_data *vc)
 935 {
 936         WARN_CONSOLE_UNLOCKED();
 937
 938         if (vc->vc_sw->con_flush_scrollback)
 939                 vc->vc_sw->con_flush_scrollback(vc);
 940 }
 941
 942 /*
 943  *      Redrawing of screen
 944  */
 945
 946 void clear_buffer_attributes(struct vc_data *vc)
 947 {
 948         unsigned short *p = (unsigned short *)vc->vc_origin;
 949         int count = vc->vc_screenbuf_size / 2;
 950         int mask = vc->vc_hi_font_mask | 0xff;
 951
 952         for (; count > 0; count--, p++) {
 953                 scr_writew((scr_readw(p)&mask) | (vc->vc_video_erase_char & ~mask), p);
 954         }
 955 }
 956
 957 void redraw_screen(struct vc_data *vc, int is_switch)
 958 {
 959         int redraw = 0;
 960
 961         WARN_CONSOLE_UNLOCKED();
 962
 963         if (!vc) {
 964                 /* strange ... */
 965                 /* printk("redraw_screen: tty %d not allocated ??\n", new_console+1); */
 966                 return;
 967         }
 968
 969         if (is_switch) {
 970                 struct vc_data *old_vc = vc_cons[fg_console].d;
 971                 if (old_vc == vc)
 972                         return;
 973                 if (!con_is_visible(vc))
 974                         redraw = 1;
 975                 *vc->vc_display_fg = vc;
 976                 fg_console = vc->vc_num;
 977                 hide_cursor(old_vc);
 978                 if (!con_is_visible(old_vc)) {
 979                         save_screen(old_vc);
 980                         set_origin(old_vc);
 981                 }
 982                 if (tty0dev)
 983                         sysfs_notify(&tty0dev->kobj, NULL, "active");
 984         } else {
 985                 hide_cursor(vc);
 986                 redraw = 1;
 987         }
 988
 989         if (redraw) {
 990                 int update;
 991                 int old_was_color = vc->vc_can_do_color;
 992
 993                 set_origin(vc);
 994                 update = vc->vc_sw->con_switch(vc);
 995                 set_palette(vc);
 996                 /*
 997                  * If console changed from mono<->color, the best we can do
 998                  * is to clear the buffer attributes. As it currently stands,
 999                  * rebuilding new attributes from the old buffer is not doable
1000                  * without overly complex code.
1001                  */
1002                 if (old_was_color != vc->vc_can_do_color) {
1003                         update_attr(vc);
1004                         clear_buffer_attributes(vc);
1005                 }
1006
1007                 if (update && vc->vc_mode != KD_GRAPHICS)
1008                         do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
1009         }
1010         set_cursor(vc);
1011         if (is_switch) {
1012                 set_leds();
1013                 compute_shiftstate();
1014                 notify_update(vc);
1015         }
1016 }
1017
1018 /*
1019  *      Allocation, freeing and resizing of VTs.
1020  */
1021
1022 int vc_cons_allocated(unsigned int i)
1023 {
1024         return (i < MAX_NR_CONSOLES && vc_cons[i].d);
1025 }
1026
1027 static void visual_init(struct vc_data *vc, int num, int init)
1028 {
1029         /* ++Geert: vc->vc_sw->con_init determines console size */
1030         if (vc->vc_sw)
1031                 module_put(vc->vc_sw->owner);
1032         vc->vc_sw = conswitchp;
1033 #ifndef VT_SINGLE_DRIVER
1034         if (con_driver_map[num])
1035                 vc->vc_sw = con_driver_map[num];
1036 #endif
1037         __module_get(vc->vc_sw->owner);
1038         vc->vc_num = num;
1039         vc->vc_display_fg = &master_display_fg;
1040         if (vc->vc_uni_pagedir_loc)
1041                 con_free_unimap(vc);
1042         vc->vc_uni_pagedir_loc = &vc->vc_uni_pagedir;
1043         vc->vc_uni_pagedir = NULL;
1044         vc->vc_hi_font_mask = 0;
1045         vc->vc_complement_mask = 0;
1046         vc->vc_can_do_color = 0;
1047         vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1048         vc->vc_sw->con_init(vc, init);
1049         if (!vc->vc_complement_mask)
1050                 vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
1051         vc->vc_s_complement_mask = vc->vc_complement_mask;
1052         vc->vc_size_row = vc->vc_cols << 1;
1053         vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
1054 }
1055
1056 int vc_allocate(unsigned int currcons)  /* return 0 on success */
1057 {
1058         struct vt_notifier_param param;
1059         struct vc_data *vc;
1060
1061         WARN_CONSOLE_UNLOCKED();
1062
1063         if (currcons >= MAX_NR_CONSOLES)
1064                 return -ENXIO;
1065
1066         if (vc_cons[currcons].d)
1067                 return 0;
1068
1069         /* due to the granularity of kmalloc, we waste some memory here */
1070         /* the alloc is done in two steps, to optimize the common situation
1071            of a 25x80 console (structsize=216, screenbuf_size=4000) */
1072         /* although the numbers above are not valid since long ago, the
1073            point is still up-to-date and the comment still has its value
1074            even if only as a historical artifact.  --mj, July 1998 */
1075         param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL);
1076         if (!vc)
1077                 return -ENOMEM;
1078
1079         vc_cons[currcons].d = vc;
1080         tty_port_init(&vc->port);
1081         INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
1082
1083         visual_init(vc, currcons, 1);
1084
1085         if (!*vc->vc_uni_pagedir_loc)
1086                 con_set_default_unimap(vc);
1087
1088         vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
1089         if (!vc->vc_screenbuf)
1090                 goto err_free;
1091
1092         /* If no drivers have overridden us and the user didn't pass a
1093            boot option, default to displaying the cursor */
1094         if (global_cursor_default == -1)
1095                 global_cursor_default = 1;
1096
1097         vc_init(vc, vc->vc_rows, vc->vc_cols, 1);
1098         vcs_make_sysfs(currcons);
1099         atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, &param);
1100
1101         return 0;
1102 err_free:
1103         kfree(vc);
1104         vc_cons[currcons].d = NULL;
1105         return -ENOMEM;
1106 }
1107
1108 static inline int resize_screen(struct vc_data *vc, int width, int height,
1109                                 int user)
1110 {
1111         /* Resizes the resolution of the display adapater */
1112         int err = 0;
1113
1114         if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_resize)
1115                 err = vc->vc_sw->con_resize(vc, width, height, user);
1116
1117         return err;
1118 }
1119
1120 /*
1121  * Change # of rows and columns (0 means unchanged/the size of fg_console)
1122  * [this is to be used together with some user program
1123  * like resize that changes the hardware videomode]
1124  */
1125 #define VC_RESIZE_MAXCOL (32767)
1126 #define VC_RESIZE_MAXROW (32767)
1127
1128 /**
1129  *      vc_do_resize    -       resizing method for the tty
1130  *      @tty: tty being resized
1131  *      @real_tty: real tty (different to tty if a pty/tty pair)
1132  *      @vc: virtual console private data
1133  *      @cols: columns
1134  *      @lines: lines
1135  *
1136  *      Resize a virtual console, clipping according to the actual constraints.
1137  *      If the caller passes a tty structure then update the termios winsize
1138  *      information and perform any necessary signal handling.
1139  *
1140  *      Caller must hold the console semaphore. Takes the termios rwsem and
1141  *      ctrl_lock of the tty IFF a tty is passed.
1142  */
1143
1144 static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
1145                                 unsigned int cols, unsigned int lines)
1146 {
1147         unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
1148         unsigned long end;
1149         unsigned int old_rows, old_row_size, first_copied_row;
1150         unsigned int new_cols, new_rows, new_row_size, new_screen_size;
1151         unsigned int user;
1152         unsigned short *newscreen;
1153         struct uni_screen *new_uniscr = NULL;
1154
1155         WARN_CONSOLE_UNLOCKED();
1156
1157         if (!vc)
1158                 return -ENXIO;
1159
1160         user = vc->vc_resize_user;
1161         vc->vc_resize_user = 0;
1162
1163         if (cols > VC_RESIZE_MAXCOL || lines > VC_RESIZE_MAXROW)
1164                 return -EINVAL;
1165
1166         new_cols = (cols ? cols : vc->vc_cols);
1167         new_rows = (lines ? lines : vc->vc_rows);
1168         new_row_size = new_cols << 1;
1169         new_screen_size = new_row_size * new_rows;
1170
1171         if (new_cols == vc->vc_cols && new_rows == vc->vc_rows)
1172                 return 0;
1173
1174         if (new_screen_size > (4 << 20))
1175                 return -EINVAL;
1176         newscreen = kzalloc(new_screen_size, GFP_USER);
1177         if (!newscreen)
1178                 return -ENOMEM;
1179
1180         if (get_vc_uniscr(vc)) {
1181                 new_uniscr = vc_uniscr_alloc(new_cols, new_rows);
1182                 if (!new_uniscr) {
1183                         kfree(newscreen);
1184                         return -ENOMEM;
1185                 }
1186         }
1187
1188         if (vc == sel_cons)
1189                 clear_selection();
1190
1191         old_rows = vc->vc_rows;
1192         old_row_size = vc->vc_size_row;
1193
1194         err = resize_screen(vc, new_cols, new_rows, user);
1195         if (err) {
1196                 kfree(newscreen);
1197                 kfree(new_uniscr);
1198                 return err;
1199         }
1200
1201         vc->vc_rows = new_rows;
1202         vc->vc_cols = new_cols;
1203         vc->vc_size_row = new_row_size;
1204         vc->vc_screenbuf_size = new_screen_size;
1205
1206         rlth = min(old_row_size, new_row_size);
1207         rrem = new_row_size - rlth;
1208         old_origin = vc->vc_origin;
1209         new_origin = (long) newscreen;
1210         new_scr_end = new_origin + new_screen_size;
1211
1212         if (vc->vc_y > new_rows) {
1213                 if (old_rows - vc->vc_y < new_rows) {
1214                         /*
1215                          * Cursor near the bottom, copy contents from the
1216                          * bottom of buffer
1217                          */
1218                         first_copied_row = (old_rows - new_rows);
1219                 } else {
1220                         /*
1221                          * Cursor is in no man's land, copy 1/2 screenful
1222                          * from the top and bottom of cursor position
1223                          */
1224                         first_copied_row = (vc->vc_y - new_rows/2);
1225                 }
1226                 old_origin += first_copied_row * old_row_size;
1227         } else
1228                 first_copied_row = 0;
1229         end = old_origin + old_row_size * min(old_rows, new_rows);
1230
1231         vc_uniscr_copy_area(new_uniscr, new_cols, new_rows,
1232                             get_vc_uniscr(vc), rlth/2, first_copied_row,
1233                             min(old_rows, new_rows));
1234         vc_uniscr_set(vc, new_uniscr);
1235
1236         update_attr(vc);
1237
1238         while (old_origin < end) {
1239                 scr_memcpyw((unsigned short *) new_origin,
1240                             (unsigned short *) old_origin, rlth);
1241                 if (rrem)
1242                         scr_memsetw((void *)(new_origin + rlth),
1243                                     vc->vc_video_erase_char, rrem);
1244                 old_origin += old_row_size;
1245                 new_origin += new_row_size;
1246         }
1247         if (new_scr_end > new_origin)
1248                 scr_memsetw((void *)new_origin, vc->vc_video_erase_char,
1249                             new_scr_end - new_origin);
1250         kfree(vc->vc_screenbuf);
1251         vc->vc_screenbuf = newscreen;
1252         vc->vc_screenbuf_size = new_screen_size;
1253         set_origin(vc);
1254
1255         /* do part of a reset_terminal() */
1256         vc->vc_top = 0;
1257         vc->vc_bottom = vc->vc_rows;
1258         gotoxy(vc, vc->vc_x, vc->vc_y);
1259         save_cur(vc);
1260
1261         if (tty) {
1262                 /* Rewrite the requested winsize data with the actual
1263                    resulting sizes */
1264                 struct winsize ws;
1265                 memset(&ws, 0, sizeof(ws));
1266                 ws.ws_row = vc->vc_rows;
1267                 ws.ws_col = vc->vc_cols;
1268                 ws.ws_ypixel = vc->vc_scan_lines;
1269                 tty_do_resize(tty, &ws);
1270         }
1271
1272         if (con_is_visible(vc))
1273                 update_screen(vc);
1274         vt_event_post(VT_EVENT_RESIZE, vc->vc_num, vc->vc_num);
1275         return err;
1276 }
1277
1278 /**
1279  *      vc_resize               -       resize a VT
1280  *      @vc: virtual console
1281  *      @cols: columns
1282  *      @rows: rows
1283  *
1284  *      Resize a virtual console as seen from the console end of things. We
1285  *      use the common vc_do_resize methods to update the structures. The
1286  *      caller must hold the console sem to protect console internals and
1287  *      vc->port.tty
1288  */
1289
1290 int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
1291 {
1292         return vc_do_resize(vc->port.tty, vc, cols, rows);
1293 }
1294
1295 /**
1296  *      vt_resize               -       resize a VT
1297  *      @tty: tty to resize
1298  *      @ws: winsize attributes
1299  *
1300  *      Resize a virtual terminal. This is called by the tty layer as we
1301  *      register our own handler for resizing. The mutual helper does all
1302  *      the actual work.
1303  *
1304  *      Takes the console sem and the called methods then take the tty
1305  *      termios_rwsem and the tty ctrl_lock in that order.
1306  */
1307 static int vt_resize(struct tty_struct *tty, struct winsize *ws)
1308 {
1309         struct vc_data *vc = tty->driver_data;
1310         int ret;
1311
1312         console_lock();
1313         ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row);
1314         console_unlock();
1315         return ret;
1316 }
1317
1318 struct vc_data *vc_deallocate(unsigned int currcons)
1319 {
1320         struct vc_data *vc = NULL;
1321
1322         WARN_CONSOLE_UNLOCKED();
1323
1324         if (vc_cons_allocated(currcons)) {
1325                 struct vt_notifier_param param;
1326
1327                 param.vc = vc = vc_cons[currcons].d;
1328                 atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, &param);
1329                 vcs_remove_sysfs(currcons);
1330                 vc->vc_sw->con_deinit(vc);
1331                 put_pid(vc->vt_pid);
1332                 module_put(vc->vc_sw->owner);
1333                 vc_uniscr_set(vc, NULL);
1334                 kfree(vc->vc_screenbuf);
1335                 vc_cons[currcons].d = NULL;
1336         }
1337         return vc;
1338 }
1339
1340 /*
1341  *      VT102 emulator
1342  */
1343
1344 #define set_kbd(vc, x)  vt_set_kbd_mode_bit((vc)->vc_num, (x))
1345 #define clr_kbd(vc, x)  vt_clr_kbd_mode_bit((vc)->vc_num, (x))
1346 #define is_kbd(vc, x)   vt_get_kbd_mode_bit((vc)->vc_num, (x))
1347
1348 #define decarm          VC_REPEAT
1349 #define decckm          VC_CKMODE
1350 #define kbdapplic       VC_APPLIC
1351 #define lnm             VC_CRLF
1352
1353 /*
1354  * this is what the terminal answers to a ESC-Z or csi0c query.
1355  */
1356 #define VT100ID "\033[?1;2c"
1357 #define VT102ID "\033[?6c"
1358
1359 const unsigned char color_table[] = { 0, 4, 2, 6, 1, 5, 3, 7,
1360                                        8,12,10,14, 9,13,11,15 };
1361
1362 /* the default colour table, for VGA+ colour systems */
1363 unsigned char default_red[] = {
1364         0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa,
1365         0x55, 0xff, 0x55, 0xff, 0x55, 0xff, 0x55, 0xff
1366 };
1367 module_param_array(default_red, byte, NULL, S_IRUGO | S_IWUSR);
1368
1369 unsigned char default_grn[] = {
1370         0x00, 0x00, 0xaa, 0x55, 0x00, 0x00, 0xaa, 0xaa,
1371         0x55, 0x55, 0xff, 0xff, 0x55, 0x55, 0xff, 0xff
1372 };
1373 module_param_array(default_grn, byte, NULL, S_IRUGO | S_IWUSR);
1374
1375 unsigned char default_blu[] = {
1376         0x00, 0x00, 0x00, 0x00, 0xaa, 0xaa, 0xaa, 0xaa,
1377         0x55, 0x55, 0x55, 0x55, 0xff, 0xff, 0xff, 0xff
1378 };
1379 module_param_array(default_blu, byte, NULL, S_IRUGO | S_IWUSR);
1380
1381 /*
1382  * gotoxy() must verify all boundaries, because the arguments
1383  * might also be negative. If the given position is out of
1384  * bounds, the cursor is placed at the nearest margin.
1385  */
1386 static void gotoxy(struct vc_data *vc, int new_x, int new_y)
1387 {
1388         int min_y, max_y;
1389
1390         if (new_x < 0)
1391                 vc->vc_x = 0;
1392         else {
1393                 if (new_x >= vc->vc_cols)
1394                         vc->vc_x = vc->vc_cols - 1;
1395                 else
1396                         vc->vc_x = new_x;
1397         }
1398
1399         if (vc->vc_decom) {
1400                 min_y = vc->vc_top;
1401                 max_y = vc->vc_bottom;
1402         } else {
1403                 min_y = 0;
1404                 max_y = vc->vc_rows;
1405         }
1406         if (new_y < min_y)
1407                 vc->vc_y = min_y;
1408         else if (new_y >= max_y)
1409                 vc->vc_y = max_y - 1;
1410         else
1411                 vc->vc_y = new_y;
1412         vc->vc_pos = vc->vc_origin + vc->vc_y * vc->vc_size_row + (vc->vc_x<<1);
1413         vc->vc_need_wrap = 0;
1414 }
1415
1416 /* for absolute user moves, when decom is set */
1417 static void gotoxay(struct vc_data *vc, int new_x, int new_y)
1418 {
1419         gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y);
1420 }
1421
1422 void scrollback(struct vc_data *vc)
1423 {
1424         scrolldelta(-(vc->vc_rows / 2));
1425 }
1426
1427 void scrollfront(struct vc_data *vc, int lines)
1428 {
1429         if (!lines)
1430                 lines = vc->vc_rows / 2;
1431         scrolldelta(lines);
1432 }
1433
1434 static void lf(struct vc_data *vc)
1435 {
1436         /* don't scroll if above bottom of scrolling region, or
1437          * if below scrolling region
1438          */
1439         if (vc->vc_y + 1 == vc->vc_bottom)
1440                 con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_UP, 1);
1441         else if (vc->vc_y < vc->vc_rows - 1) {
1442                 vc->vc_y++;
1443                 vc->vc_pos += vc->vc_size_row;
1444         }
1445         vc->vc_need_wrap = 0;
1446         notify_write(vc, '\n');
1447 }
1448
1449 static void ri(struct vc_data *vc)
1450 {
1451         /* don't scroll if below top of scrolling region, or
1452          * if above scrolling region
1453          */
1454         if (vc->vc_y == vc->vc_top)
1455                 con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_DOWN, 1);
1456         else if (vc->vc_y > 0) {
1457                 vc->vc_y--;
1458                 vc->vc_pos -= vc->vc_size_row;
1459         }
1460         vc->vc_need_wrap = 0;
1461 }
1462
1463 static inline void cr(struct vc_data *vc)
1464 {
1465         vc->vc_pos -= vc->vc_x << 1;
1466         vc->vc_need_wrap = vc->vc_x = 0;
1467         notify_write(vc, '\r');
1468 }
1469
1470 static inline void bs(struct vc_data *vc)
1471 {
1472         if (vc->vc_x) {
1473                 vc->vc_pos -= 2;
1474                 vc->vc_x--;
1475                 vc->vc_need_wrap = 0;
1476                 notify_write(vc, '\b');
1477         }
1478 }
1479
1480 static inline void del(struct vc_data *vc)
1481 {
1482         /* ignored */
1483 }
1484
1485 static void csi_J(struct vc_data *vc, int vpar)
1486 {
1487         unsigned int count;
1488         unsigned short * start;
1489
1490         switch (vpar) {
1491                 case 0: /* erase from cursor to end of display */
1492                         vc_uniscr_clear_line(vc, vc->vc_x,
1493                                              vc->vc_cols - vc->vc_x);
1494                         vc_uniscr_clear_lines(vc, vc->vc_y + 1,
1495                                               vc->vc_rows - vc->vc_y - 1);
1496                         count = (vc->vc_scr_end - vc->vc_pos) >> 1;
1497                         start = (unsigned short *)vc->vc_pos;
1498                         break;
1499                 case 1: /* erase from start to cursor */
1500                         vc_uniscr_clear_line(vc, 0, vc->vc_x + 1);
1501                         vc_uniscr_clear_lines(vc, 0, vc->vc_y);
1502                         count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1;
1503                         start = (unsigned short *)vc->vc_origin;
1504                         break;
1505                 case 2: /* erase whole display */
1506                 case 3: /* (and scrollback buffer later) */
1507                         vc_uniscr_clear_lines(vc, 0, vc->vc_rows);
1508                         count = vc->vc_cols * vc->vc_rows;
1509                         start = (unsigned short *)vc->vc_origin;
1510                         break;
1511                 default:
1512                         return;
1513         }
1514         scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1515         if (vpar == 3) {
1516                 set_origin(vc);
1517                 flush_scrollback(vc);
1518                 if (con_is_visible(vc))
1519                         update_screen(vc);
1520         } else if (con_should_update(vc))
1521                 do_update_region(vc, (unsigned long) start, count);
1522         vc->vc_need_wrap = 0;
1523 }
1524
1525 static void csi_K(struct vc_data *vc, int vpar)
1526 {
1527         unsigned int count;
1528         unsigned short *start = (unsigned short *)vc->vc_pos;
1529         int offset;
1530
1531         switch (vpar) {
1532                 case 0: /* erase from cursor to end of line */
1533                         offset = 0;
1534                         count = vc->vc_cols - vc->vc_x;
1535                         break;
1536                 case 1: /* erase from start of line to cursor */
1537                         offset = -vc->vc_x;
1538                         count = vc->vc_x + 1;
1539                         break;
1540                 case 2: /* erase whole line */
1541                         offset = -vc->vc_x;
1542                         count = vc->vc_cols;
1543                         break;
1544                 default:
1545                         return;
1546         }
1547         vc_uniscr_clear_line(vc, vc->vc_x + offset, count);
1548         scr_memsetw(start + offset, vc->vc_video_erase_char, 2 * count);
1549         vc->vc_need_wrap = 0;
1550         if (con_should_update(vc))
1551                 do_update_region(vc, (unsigned long)(start + offset), count);
1552 }
1553
1554 static void csi_X(struct vc_data *vc, int vpar) /* erase the following vpar positions */
1555 {                                         /* not vt100? */
1556         int count;
1557
1558         if (!vpar)
1559                 vpar++;
1560         count = (vpar > vc->vc_cols - vc->vc_x) ? (vc->vc_cols - vc->vc_x) : vpar;
1561
1562         vc_uniscr_clear_line(vc, vc->vc_x, count);
1563         scr_memsetw((unsigned short *)vc->vc_pos, vc->vc_video_erase_char, 2 * count);
1564         if (con_should_update(vc))
1565                 vc->vc_sw->con_clear(vc, vc->vc_y, vc->vc_x, 1, count);
1566         vc->vc_need_wrap = 0;
1567 }
1568
1569 static void default_attr(struct vc_data *vc)
1570 {
1571         vc->vc_intensity = 1;
1572         vc->vc_italic = 0;
1573         vc->vc_underline = 0;
1574         vc->vc_reverse = 0;
1575         vc->vc_blink = 0;
1576         vc->vc_color = vc->vc_def_color;
1577 }
1578
1579 struct rgb { u8 r; u8 g; u8 b; };
1580
1581 static void rgb_from_256(int i, struct rgb *c)
1582 {
1583         if (i < 8) {            /* Standard colours. */
1584                 c->r = i&1 ? 0xaa : 0x00;
1585                 c->g = i&2 ? 0xaa : 0x00;
1586                 c->b = i&4 ? 0xaa : 0x00;
1587         } else if (i < 16) {
1588                 c->r = i&1 ? 0xff : 0x55;
1589                 c->g = i&2 ? 0xff : 0x55;
1590                 c->b = i&4 ? 0xff : 0x55;
1591         } else if (i < 232) {   /* 6x6x6 colour cube. */
1592                 c->r = (i - 16) / 36 * 85 / 2;
1593                 c->g = (i - 16) / 6 % 6 * 85 / 2;
1594                 c->b = (i - 16) % 6 * 85 / 2;
1595         } else                  /* Grayscale ramp. */
1596                 c->r = c->g = c->b = i * 10 - 2312;
1597 }
1598
1599 static void rgb_foreground(struct vc_data *vc, const struct rgb *c)
1600 {
1601         u8 hue = 0, max = max3(c->r, c->g, c->b);
1602
1603         if (c->r > max / 2)
1604                 hue |= 4;
1605         if (c->g > max / 2)
1606                 hue |= 2;
1607         if (c->b > max / 2)
1608                 hue |= 1;
1609
1610         if (hue == 7 && max <= 0x55) {
1611                 hue = 0;
1612                 vc->vc_intensity = 2;
1613         } else if (max > 0xaa)
1614                 vc->vc_intensity = 2;
1615         else
1616                 vc->vc_intensity = 1;
1617
1618         vc->vc_color = (vc->vc_color & 0xf0) | hue;
1619 }
1620
1621 static void rgb_background(struct vc_data *vc, const struct rgb *c)
1622 {
1623         /* For backgrounds, err on the dark side. */
1624         vc->vc_color = (vc->vc_color & 0x0f)
1625                 | (c->r&0x80) >> 1 | (c->g&0x80) >> 2 | (c->b&0x80) >> 3;
1626 }
1627
1628 /*
1629  * ITU T.416 Higher colour modes. They break the usual properties of SGR codes
1630  * and thus need to be detected and ignored by hand. Strictly speaking, that
1631  * standard also wants : rather than ; as separators, contrary to ECMA-48, but
1632  * no one produces such codes and almost no one accepts them.
1633  *
1634  * Subcommands 3 (CMY) and 4 (CMYK) are so insane there's no point in
1635  * supporting them.
1636  */
1637 static int vc_t416_color(struct vc_data *vc, int i,
1638                 void(*set_color)(struct vc_data *vc, const struct rgb *c))
1639 {
1640         struct rgb c;
1641
1642         i++;
1643         if (i > vc->vc_npar)
1644                 return i;
1645
1646         if (vc->vc_par[i] == 5 && i + 1 <= vc->vc_npar) {
1647                 /* 256 colours */
1648                 i++;
1649                 rgb_from_256(vc->vc_par[i], &c);
1650         } else if (vc->vc_par[i] == 2 && i + 3 <= vc->vc_npar) {
1651                 /* 24 bit */
1652                 c.r = vc->vc_par[i + 1];
1653                 c.g = vc->vc_par[i + 2];
1654                 c.b = vc->vc_par[i + 3];
1655                 i += 3;
1656         } else
1657                 return i;
1658
1659         set_color(vc, &c);
1660
1661         return i;
1662 }
1663
1664 /* console_lock is held */
1665 static void csi_m(struct vc_data *vc)
1666 {
1667         int i;
1668
1669         for (i = 0; i <= vc->vc_npar; i++)
1670                 switch (vc->vc_par[i]) {
1671                 case 0: /* all attributes off */
1672                         default_attr(vc);
1673                         break;
1674                 case 1:
1675                         vc->vc_intensity = 2;
1676                         break;
1677                 case 2:
1678                         vc->vc_intensity = 0;
1679                         break;
1680                 case 3:
1681                         vc->vc_italic = 1;
1682                         break;
1683                 case 21:
1684                         /*
1685                          * No console drivers support double underline, so
1686                          * convert it to a single underline.
1687                          */
1688                 case 4:
1689                         vc->vc_underline = 1;
1690                         break;
1691                 case 5:
1692                         vc->vc_blink = 1;
1693                         break;
1694                 case 7:
1695                         vc->vc_reverse = 1;
1696                         break;
1697                 case 10: /* ANSI X3.64-1979 (SCO-ish?)
1698                           * Select primary font, don't display control chars if
1699                           * defined, don't set bit 8 on output.
1700                           */
1701                         vc->vc_translate = set_translate(vc->vc_charset == 0
1702                                         ? vc->vc_G0_charset
1703                                         : vc->vc_G1_charset, vc);
1704                         vc->vc_disp_ctrl = 0;
1705                         vc->vc_toggle_meta = 0;
1706                         break;
1707                 case 11: /* ANSI X3.64-1979 (SCO-ish?)
1708                           * Select first alternate font, lets chars < 32 be
1709                           * displayed as ROM chars.
1710                           */
1711                         vc->vc_translate = set_translate(IBMPC_MAP, vc);
1712                         vc->vc_disp_ctrl = 1;
1713                         vc->vc_toggle_meta = 0;
1714                         break;
1715                 case 12: /* ANSI X3.64-1979 (SCO-ish?)
1716                           * Select second alternate font, toggle high bit
1717                           * before displaying as ROM char.
1718                           */
1719                         vc->vc_translate = set_translate(IBMPC_MAP, vc);
1720                         vc->vc_disp_ctrl = 1;
1721                         vc->vc_toggle_meta = 1;
1722                         break;
1723                 case 22:
1724                         vc->vc_intensity = 1;
1725                         break;
1726                 case 23:
1727                         vc->vc_italic = 0;
1728                         break;
1729                 case 24:
1730                         vc->vc_underline = 0;
1731                         break;
1732                 case 25:
1733                         vc->vc_blink = 0;
1734                         break;
1735                 case 27:
1736                         vc->vc_reverse = 0;
1737                         break;
1738                 case 38:
1739                         i = vc_t416_color(vc, i, rgb_foreground);
1740                         break;
1741                 case 48:
1742                         i = vc_t416_color(vc, i, rgb_background);
1743                         break;
1744                 case 39:
1745                         vc->vc_color = (vc->vc_def_color & 0x0f) |
1746                                 (vc->vc_color & 0xf0);
1747                         break;
1748                 case 49:
1749                         vc->vc_color = (vc->vc_def_color & 0xf0) |
1750                                 (vc->vc_color & 0x0f);
1751                         break;
1752                 default:
1753                         if (vc->vc_par[i] >= 90 && vc->vc_par[i] <= 107) {
1754                                 if (vc->vc_par[i] < 100)
1755                                         vc->vc_intensity = 2;
1756                                 vc->vc_par[i] -= 60;
1757                         }
1758                         if (vc->vc_par[i] >= 30 && vc->vc_par[i] <= 37)
1759                                 vc->vc_color = color_table[vc->vc_par[i] - 30]
1760                                         | (vc->vc_color & 0xf0);
1761                         else if (vc->vc_par[i] >= 40 && vc->vc_par[i] <= 47)
1762                                 vc->vc_color = (color_table[vc->vc_par[i] - 40] << 4)
1763                                         | (vc->vc_color & 0x0f);
1764                         break;
1765                 }
1766         update_attr(vc);
1767 }
1768
1769 static void respond_string(const char *p, struct tty_port *port)
1770 {
1771         while (*p) {
1772                 tty_insert_flip_char(port, *p, 0);
1773                 p++;
1774         }
1775         tty_schedule_flip(port);
1776 }
1777
1778 static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
1779 {
1780         char buf[40];
1781
1782         sprintf(buf, "\033[%d;%dR", vc->vc_y + (vc->vc_decom ? vc->vc_top + 1 : 1), vc->vc_x + 1);
1783         respond_string(buf, tty->port);
1784 }
1785
1786 static inline void status_report(struct tty_struct *tty)
1787 {
1788         respond_string("\033[0n", tty->port);   /* Terminal ok */
1789 }
1790
1791 static inline void respond_ID(struct tty_struct *tty)
1792 {
1793         respond_string(VT102ID, tty->port);
1794 }
1795
1796 void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
1797 {
1798         char buf[8];
1799
1800         sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt), (char)('!' + mrx),
1801                 (char)('!' + mry));
1802         respond_string(buf, tty->port);
1803 }
1804
1805 /* invoked via ioctl(TIOCLINUX) and through set_selection */
1806 int mouse_reporting(void)
1807 {
1808         return vc_cons[fg_console].d->vc_report_mouse;
1809 }
1810
1811 /* console_lock is held */
1812 static void set_mode(struct vc_data *vc, int on_off)
1813 {
1814         int i;
1815
1816         for (i = 0; i <= vc->vc_npar; i++)
1817                 if (vc->vc_ques) {
1818                         switch(vc->vc_par[i]) { /* DEC private modes set/reset */
1819                         case 1:                 /* Cursor keys send ^[Ox/^[[x */
1820                                 if (on_off)
1821                                         set_kbd(vc, decckm);
1822                                 else
1823                                         clr_kbd(vc, decckm);
1824                                 break;
1825                         case 3: /* 80/132 mode switch unimplemented */
1826 #if 0
1827                                 vc_resize(deccolm ? 132 : 80, vc->vc_rows);
1828                                 /* this alone does not suffice; some user mode
1829                                    utility has to change the hardware regs */
1830 #endif
1831                                 break;
1832                         case 5:                 /* Inverted screen on/off */
1833                                 if (vc->vc_decscnm != on_off) {
1834                                         vc->vc_decscnm = on_off;
1835                                         invert_screen(vc, 0, vc->vc_screenbuf_size, 0);
1836                                         update_attr(vc);
1837                                 }
1838                                 break;
1839                         case 6:                 /* Origin relative/absolute */
1840                                 vc->vc_decom = on_off;
1841                                 gotoxay(vc, 0, 0);
1842                                 break;
1843                         case 7:                 /* Autowrap on/off */
1844                                 vc->vc_decawm = on_off;
1845                                 break;
1846                         case 8:                 /* Autorepeat on/off */
1847                                 if (on_off)
1848                                         set_kbd(vc, decarm);
1849                                 else
1850                                         clr_kbd(vc, decarm);
1851                                 break;
1852                         case 9:
1853                                 vc->vc_report_mouse = on_off ? 1 : 0;
1854                                 break;
1855                         case 25:                /* Cursor on/off */
1856                                 vc->vc_deccm = on_off;
1857                                 break;
1858                         case 1000:
1859                                 vc->vc_report_mouse = on_off ? 2 : 0;
1860                                 break;
1861                         }
1862                 } else {
1863                         switch(vc->vc_par[i]) { /* ANSI modes set/reset */
1864                         case 3:                 /* Monitor (display ctrls) */
1865                                 vc->vc_disp_ctrl = on_off;
1866                                 break;
1867                         case 4:                 /* Insert Mode on/off */
1868                                 vc->vc_decim = on_off;
1869                                 break;
1870                         case 20:                /* Lf, Enter == CrLf/Lf */
1871                                 if (on_off)
1872                                         set_kbd(vc, lnm);
1873                                 else
1874                                         clr_kbd(vc, lnm);
1875                                 break;
1876                         }
1877                 }
1878 }
1879
1880 /* console_lock is held */
1881 static void setterm_command(struct vc_data *vc)
1882 {
1883         switch(vc->vc_par[0]) {
1884                 case 1: /* set color for underline mode */
1885                         if (vc->vc_can_do_color &&
1886                                         vc->vc_par[1] < 16) {
1887                                 vc->vc_ulcolor = color_table[vc->vc_par[1]];
1888                                 if (vc->vc_underline)
1889                                         update_attr(vc);
1890                         }
1891                         break;
1892                 case 2: /* set color for half intensity mode */
1893                         if (vc->vc_can_do_color &&
1894                                         vc->vc_par[1] < 16) {
1895                                 vc->vc_halfcolor = color_table[vc->vc_par[1]];
1896                                 if (vc->vc_intensity == 0)
1897                                         update_attr(vc);
1898                         }
1899                         break;
1900                 case 8: /* store colors as defaults */
1901                         vc->vc_def_color = vc->vc_attr;
1902                         if (vc->vc_hi_font_mask == 0x100)
1903                                 vc->vc_def_color >>= 1;
1904                         default_attr(vc);
1905                         update_attr(vc);
1906                         break;
1907                 case 9: /* set blanking interval */
1908                         blankinterval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60;
1909                         poke_blanked_console();
1910                         break;
1911                 case 10: /* set bell frequency in Hz */
1912                         if (vc->vc_npar >= 1)
1913                                 vc->vc_bell_pitch = vc->vc_par[1];
1914                         else
1915                                 vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
1916                         break;
1917                 case 11: /* set bell duration in msec */
1918                         if (vc->vc_npar >= 1)
1919                                 vc->vc_bell_duration = (vc->vc_par[1] < 2000) ?
1920                                         msecs_to_jiffies(vc->vc_par[1]) : 0;
1921                         else
1922                                 vc->vc_bell_duration = DEFAULT_BELL_DURATION;
1923                         break;
1924                 case 12: /* bring specified console to the front */
1925                         if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1))
1926                                 set_console(vc->vc_par[1] - 1);
1927                         break;
1928                 case 13: /* unblank the screen */
1929                         poke_blanked_console();
1930                         break;
1931                 case 14: /* set vesa powerdown interval */
1932                         vesa_off_interval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60 * HZ;
1933                         break;
1934                 case 15: /* activate the previous console */
1935                         set_console(last_console);
1936                         break;
1937                 case 16: /* set cursor blink duration in msec */
1938                         if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 &&
1939                                         vc->vc_par[1] <= USHRT_MAX)
1940                                 vc->vc_cur_blink_ms = vc->vc_par[1];
1941                         else
1942                                 vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1943                         break;
1944         }
1945 }
1946
1947 /* console_lock is held */
1948 static void csi_at(struct vc_data *vc, unsigned int nr)
1949 {
1950         if (nr > vc->vc_cols - vc->vc_x)
1951                 nr = vc->vc_cols - vc->vc_x;
1952         else if (!nr)
1953                 nr = 1;
1954         insert_char(vc, nr);
1955 }
1956
1957 /* console_lock is held */
1958 static void csi_L(struct vc_data *vc, unsigned int nr)
1959 {
1960         if (nr > vc->vc_rows - vc->vc_y)
1961                 nr = vc->vc_rows - vc->vc_y;
1962         else if (!nr)
1963                 nr = 1;
1964         con_scroll(vc, vc->vc_y, vc->vc_bottom, SM_DOWN, nr);
1965         vc->vc_need_wrap = 0;
1966 }
1967
1968 /* console_lock is held */
1969 static void csi_P(struct vc_data *vc, unsigned int nr)
1970 {
1971         if (nr > vc->vc_cols - vc->vc_x)
1972                 nr = vc->vc_cols - vc->vc_x;
1973         else if (!nr)
1974                 nr = 1;
1975         delete_char(vc, nr);
1976 }
1977
1978 /* console_lock is held */
1979 static void csi_M(struct vc_data *vc, unsigned int nr)
1980 {
1981         if (nr > vc->vc_rows - vc->vc_y)
1982                 nr = vc->vc_rows - vc->vc_y;
1983         else if (!nr)
1984                 nr=1;
1985         con_scroll(vc, vc->vc_y, vc->vc_bottom, SM_UP, nr);
1986         vc->vc_need_wrap = 0;
1987 }
1988
1989 /* console_lock is held (except via vc_init->reset_terminal */
1990 static void save_cur(struct vc_data *vc)
1991 {
1992         vc->vc_saved_x          = vc->vc_x;
1993         vc->vc_saved_y          = vc->vc_y;
1994         vc->vc_s_intensity      = vc->vc_intensity;
1995         vc->vc_s_italic         = vc->vc_italic;
1996         vc->vc_s_underline      = vc->vc_underline;
1997         vc->vc_s_blink          = vc->vc_blink;
1998         vc->vc_s_reverse        = vc->vc_reverse;
1999         vc->vc_s_charset        = vc->vc_charset;
2000         vc->vc_s_color          = vc->vc_color;
2001         vc->vc_saved_G0         = vc->vc_G0_charset;
2002         vc->vc_saved_G1         = vc->vc_G1_charset;
2003 }
2004
2005 /* console_lock is held */
2006 static void restore_cur(struct vc_data *vc)
2007 {
2008         gotoxy(vc, vc->vc_saved_x, vc->vc_saved_y);
2009         vc->vc_intensity        = vc->vc_s_intensity;
2010         vc->vc_italic           = vc->vc_s_italic;
2011         vc->vc_underline        = vc->vc_s_underline;
2012         vc->vc_blink            = vc->vc_s_blink;
2013         vc->vc_reverse          = vc->vc_s_reverse;
2014         vc->vc_charset          = vc->vc_s_charset;
2015         vc->vc_color            = vc->vc_s_color;
2016         vc->vc_G0_charset       = vc->vc_saved_G0;
2017         vc->vc_G1_charset       = vc->vc_saved_G1;
2018         vc->vc_translate        = set_translate(vc->vc_charset ? vc->vc_G1_charset : vc->vc_G0_charset, vc);
2019         update_attr(vc);
2020         vc->vc_need_wrap = 0;
2021 }
2022
2023 enum { ESnormal, ESesc, ESsquare, ESgetpars, ESfunckey,
2024         EShash, ESsetG0, ESsetG1, ESpercent, ESignore, ESnonstd,
2025         ESpalette, ESosc };
2026
2027 /* console_lock is held (except via vc_init()) */
2028 static void reset_terminal(struct vc_data *vc, int do_clear)
2029 {
2030         vc->vc_top              = 0;
2031         vc->vc_bottom           = vc->vc_rows;
2032         vc->vc_state            = ESnormal;
2033         vc->vc_ques             = 0;
2034         vc->vc_translate        = set_translate(LAT1_MAP, vc);
2035         vc->vc_G0_charset       = LAT1_MAP;
2036         vc->vc_G1_charset       = GRAF_MAP;
2037         vc->vc_charset          = 0;
2038         vc->vc_need_wrap        = 0;
2039         vc->vc_report_mouse     = 0;
2040         vc->vc_utf              = default_utf8;
2041         vc->vc_utf_count        = 0;
2042
2043         vc->vc_disp_ctrl        = 0;
2044         vc->vc_toggle_meta      = 0;
2045
2046         vc->vc_decscnm          = 0;
2047         vc->vc_decom            = 0;
2048         vc->vc_decawm           = 1;
2049         vc->vc_deccm            = global_cursor_default;
2050         vc->vc_decim            = 0;
2051
2052         vt_reset_keyboard(vc->vc_num);
2053
2054         vc->vc_cursor_type = cur_default;
2055         vc->vc_complement_mask = vc->vc_s_complement_mask;
2056
2057         default_attr(vc);
2058         update_attr(vc);
2059
2060         vc->vc_tab_stop[0]      =
2061         vc->vc_tab_stop[1]      =
2062         vc->vc_tab_stop[2]      =
2063         vc->vc_tab_stop[3]      =
2064         vc->vc_tab_stop[4]      =
2065         vc->vc_tab_stop[5]      =
2066         vc->vc_tab_stop[6]      =
2067         vc->vc_tab_stop[7]      = 0x01010101;
2068
2069         vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
2070         vc->vc_bell_duration = DEFAULT_BELL_DURATION;
2071         vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
2072
2073         gotoxy(vc, 0, 0);
2074         save_cur(vc);
2075         if (do_clear)
2076             csi_J(vc, 2);
2077 }
2078
2079 /* console_lock is held */
2080 static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
2081 {
2082         /*
2083          *  Control characters can be used in the _middle_
2084          *  of an escape sequence.
2085          */
2086         if (vc->vc_state == ESosc && c>=8 && c<=13) /* ... except for OSC */
2087                 return;
2088         switch (c) {
2089         case 0:
2090                 return;
2091         case 7:
2092                 if (vc->vc_state == ESosc)
2093                         vc->vc_state = ESnormal;
2094                 else if (vc->vc_bell_duration)
2095                         kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration);
2096                 return;
2097         case 8:
2098                 bs(vc);
2099                 return;
2100         case 9:
2101                 vc->vc_pos -= (vc->vc_x << 1);
2102                 while (vc->vc_x < vc->vc_cols - 1) {
2103                         vc->vc_x++;
2104                         if (vc->vc_tab_stop[7 & (vc->vc_x >> 5)] & (1 << (vc->vc_x & 31)))
2105                                 break;
2106                 }
2107                 vc->vc_pos += (vc->vc_x << 1);
2108                 notify_write(vc, '\t');
2109                 return;
2110         case 10: case 11: case 12:
2111                 lf(vc);
2112                 if (!is_kbd(vc, lnm))
2113                         return;
2114         case 13:
2115                 cr(vc);
2116                 return;
2117         case 14:
2118                 vc->vc_charset = 1;
2119                 vc->vc_translate = set_translate(vc->vc_G1_charset, vc);
2120                 vc->vc_disp_ctrl = 1;
2121                 return;
2122         case 15:
2123                 vc->vc_charset = 0;
2124                 vc->vc_translate = set_translate(vc->vc_G0_charset, vc);
2125                 vc->vc_disp_ctrl = 0;
2126                 return;
2127         case 24: case 26:
2128                 vc->vc_state = ESnormal;
2129                 return;
2130         case 27:
2131                 vc->vc_state = ESesc;
2132                 return;
2133         case 127:
2134                 del(vc);
2135                 return;
2136         case 128+27:
2137                 vc->vc_state = ESsquare;
2138                 return;
2139         }
2140         switch(vc->vc_state) {
2141         case ESesc:
2142                 vc->vc_state = ESnormal;
2143                 switch (c) {
2144                 case '[':
2145                         vc->vc_state = ESsquare;
2146                         return;
2147                 case ']':
2148                         vc->vc_state = ESnonstd;
2149                         return;
2150                 case '%':
2151                         vc->vc_state = ESpercent;
2152                         return;
2153                 case 'E':
2154                         cr(vc);
2155                         lf(vc);
2156                         return;
2157                 case 'M':
2158                         ri(vc);
2159                         return;
2160                 case 'D':
2161                         lf(vc);
2162                         return;
2163                 case 'H':
2164                         vc->vc_tab_stop[7 & (vc->vc_x >> 5)] |= (1 << (vc->vc_x & 31));
2165                         return;
2166                 case 'Z':
2167                         respond_ID(tty);
2168                         return;
2169                 case '7':
2170                         save_cur(vc);
2171                         return;
2172                 case '8':
2173                         restore_cur(vc);
2174                         return;
2175                 case '(':
2176                         vc->vc_state = ESsetG0;
2177                         return;
2178                 case ')':
2179                         vc->vc_state = ESsetG1;
2180                         return;
2181                 case '#':
2182                         vc->vc_state = EShash;
2183                         return;
2184                 case 'c':
2185                         reset_terminal(vc, 1);
2186                         return;
2187                 case '>':  /* Numeric keypad */
2188                         clr_kbd(vc, kbdapplic);
2189                         return;
2190                 case '=':  /* Appl. keypad */
2191                         set_kbd(vc, kbdapplic);
2192                         return;
2193                 }
2194                 return;
2195         case ESnonstd:
2196                 if (c=='P') {   /* palette escape sequence */
2197                         for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2198                                 vc->vc_par[vc->vc_npar] = 0;
2199                         vc->vc_npar = 0;
2200                         vc->vc_state = ESpalette;
2201                         return;
2202                 } else if (c=='R') {   /* reset palette */
2203                         reset_palette(vc);
2204                         vc->vc_state = ESnormal;
2205                 } else if (c>='0' && c<='9')
2206                         vc->vc_state = ESosc;
2207                 else
2208                         vc->vc_state = ESnormal;
2209                 return;
2210         case ESpalette:
2211                 if (isxdigit(c)) {
2212                         vc->vc_par[vc->vc_npar++] = hex_to_bin(c);
2213                         if (vc->vc_npar == 7) {
2214                                 int i = vc->vc_par[0] * 3, j = 1;
2215                                 vc->vc_palette[i] = 16 * vc->vc_par[j++];
2216                                 vc->vc_palette[i++] += vc->vc_par[j++];
2217                                 vc->vc_palette[i] = 16 * vc->vc_par[j++];
2218                                 vc->vc_palette[i++] += vc->vc_par[j++];
2219                                 vc->vc_palette[i] = 16 * vc->vc_par[j++];
2220                                 vc->vc_palette[i] += vc->vc_par[j];
2221                                 set_palette(vc);
2222                                 vc->vc_state = ESnormal;
2223                         }
2224                 } else
2225                         vc->vc_state = ESnormal;
2226                 return;
2227         case ESsquare:
2228                 for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2229                         vc->vc_par[vc->vc_npar] = 0;
2230                 vc->vc_npar = 0;
2231                 vc->vc_state = ESgetpars;
2232                 if (c == '[') { /* Function key */
2233                         vc->vc_state=ESfunckey;
2234                         return;
2235                 }
2236                 vc->vc_ques = (c == '?');
2237                 if (vc->vc_ques)
2238                         return;
2239         case ESgetpars:
2240                 if (c == ';' && vc->vc_npar < NPAR - 1) {
2241                         vc->vc_npar++;
2242                         return;
2243                 } else if (c>='0' && c<='9') {
2244                         vc->vc_par[vc->vc_npar] *= 10;
2245                         vc->vc_par[vc->vc_npar] += c - '0';
2246                         return;
2247                 }
2248                 vc->vc_state = ESnormal;
2249                 switch(c) {
2250                 case 'h':
2251                         set_mode(vc, 1);
2252                         return;
2253                 case 'l':
2254                         set_mode(vc, 0);
2255                         return;
2256                 case 'c':
2257                         if (vc->vc_ques) {
2258                                 if (vc->vc_par[0])
2259                                         vc->vc_cursor_type = vc->vc_par[0] | (vc->vc_par[1] << 8) | (vc->vc_par[2] << 16);
2260                                 else
2261                                         vc->vc_cursor_type = cur_default;
2262                                 return;
2263                         }
2264                         break;
2265                 case 'm':
2266                         if (vc->vc_ques) {
2267                                 clear_selection();
2268                                 if (vc->vc_par[0])
2269                                         vc->vc_complement_mask = vc->vc_par[0] << 8 | vc->vc_par[1];
2270                                 else
2271                                         vc->vc_complement_mask = vc->vc_s_complement_mask;
2272                                 return;
2273                         }
2274                         break;
2275                 case 'n':
2276                         if (!vc->vc_ques) {
2277                                 if (vc->vc_par[0] == 5)
2278                                         status_report(tty);
2279                                 else if (vc->vc_par[0] == 6)
2280                                         cursor_report(vc, tty);
2281                         }
2282                         return;
2283                 }
2284                 if (vc->vc_ques) {
2285                         vc->vc_ques = 0;
2286                         return;
2287                 }
2288                 switch(c) {
2289                 case 'G': case '`':
2290                         if (vc->vc_par[0])
2291                                 vc->vc_par[0]--;
2292                         gotoxy(vc, vc->vc_par[0], vc->vc_y);
2293                         return;
2294                 case 'A':
2295                         if (!vc->vc_par[0])
2296                                 vc->vc_par[0]++;
2297                         gotoxy(vc, vc->vc_x, vc->vc_y - vc->vc_par[0]);
2298                         return;
2299                 case 'B': case 'e':
2300                         if (!vc->vc_par[0])
2301                                 vc->vc_par[0]++;
2302                         gotoxy(vc, vc->vc_x, vc->vc_y + vc->vc_par[0]);
2303                         return;
2304                 case 'C': case 'a':
2305                         if (!vc->vc_par[0])
2306                                 vc->vc_par[0]++;
2307                         gotoxy(vc, vc->vc_x + vc->vc_par[0], vc->vc_y);
2308                         return;
2309                 case 'D':
2310                         if (!vc->vc_par[0])
2311                                 vc->vc_par[0]++;
2312                         gotoxy(vc, vc->vc_x - vc->vc_par[0], vc->vc_y);
2313                         return;
2314                 case 'E':
2315                         if (!vc->vc_par[0])
2316                                 vc->vc_par[0]++;
2317                         gotoxy(vc, 0, vc->vc_y + vc->vc_par[0]);
2318                         return;
2319                 case 'F':
2320                         if (!vc->vc_par[0])
2321                                 vc->vc_par[0]++;
2322                         gotoxy(vc, 0, vc->vc_y - vc->vc_par[0]);
2323                         return;
2324                 case 'd':
2325                         if (vc->vc_par[0])
2326                                 vc->vc_par[0]--;
2327                         gotoxay(vc, vc->vc_x ,vc->vc_par[0]);
2328                         return;
2329                 case 'H': case 'f':
2330                         if (vc->vc_par[0])
2331                                 vc->vc_par[0]--;
2332                         if (vc->vc_par[1])
2333                                 vc->vc_par[1]--;
2334                         gotoxay(vc, vc->vc_par[1], vc->vc_par[0]);
2335                         return;
2336                 case 'J':
2337                         csi_J(vc, vc->vc_par[0]);
2338                         return;
2339                 case 'K':
2340                         csi_K(vc, vc->vc_par[0]);
2341                         return;
2342                 case 'L':
2343                         csi_L(vc, vc->vc_par[0]);
2344                         return;
2345                 case 'M':
2346                         csi_M(vc, vc->vc_par[0]);
2347                         return;
2348                 case 'P':
2349                         csi_P(vc, vc->vc_par[0]);
2350                         return;
2351                 case 'c':
2352                         if (!vc->vc_par[0])
2353                                 respond_ID(tty);
2354                         return;
2355                 case 'g':
2356                         if (!vc->vc_par[0])
2357                                 vc->vc_tab_stop[7 & (vc->vc_x >> 5)] &= ~(1 << (vc->vc_x & 31));
2358                         else if (vc->vc_par[0] == 3) {
2359                                 vc->vc_tab_stop[0] =
2360                                         vc->vc_tab_stop[1] =
2361                                         vc->vc_tab_stop[2] =
2362                                         vc->vc_tab_stop[3] =
2363                                         vc->vc_tab_stop[4] =
2364                                         vc->vc_tab_stop[5] =
2365                                         vc->vc_tab_stop[6] =
2366                                         vc->vc_tab_stop[7] = 0;
2367                         }
2368                         return;
2369                 case 'm':
2370                         csi_m(vc);
2371                         return;
2372                 case 'q': /* DECLL - but only 3 leds */
2373                         /* map 0,1,2,3 to 0,1,2,4 */
2374                         if (vc->vc_par[0] < 4)
2375                                 vt_set_led_state(vc->vc_num,
2376                                             (vc->vc_par[0] < 3) ? vc->vc_par[0] : 4);
2377                         return;
2378                 case 'r':
2379                         if (!vc->vc_par[0])
2380                                 vc->vc_par[0]++;
2381                         if (!vc->vc_par[1])
2382                                 vc->vc_par[1] = vc->vc_rows;
2383                         /* Minimum allowed region is 2 lines */
2384                         if (vc->vc_par[0] < vc->vc_par[1] &&
2385                             vc->vc_par[1] <= vc->vc_rows) {
2386                                 vc->vc_top = vc->vc_par[0] - 1;
2387                                 vc->vc_bottom = vc->vc_par[1];
2388                                 gotoxay(vc, 0, 0);
2389                         }
2390                         return;
2391                 case 's':
2392                         save_cur(vc);
2393                         return;
2394                 case 'u':
2395                         restore_cur(vc);
2396                         return;
2397                 case 'X':
2398                         csi_X(vc, vc->vc_par[0]);
2399                         return;
2400                 case '@':
2401                         csi_at(vc, vc->vc_par[0]);
2402                         return;
2403                 case ']': /* setterm functions */
2404                         setterm_command(vc);
2405                         return;
2406                 }
2407                 return;
2408         case ESpercent:
2409                 vc->vc_state = ESnormal;
2410                 switch (c) {
2411                 case '@':  /* defined in ISO 2022 */
2412                         vc->vc_utf = 0;
2413                         return;
2414                 case 'G':  /* prelim official escape code */
2415                 case '8':  /* retained for compatibility */
2416                         vc->vc_utf = 1;
2417                         return;
2418                 }
2419                 return;
2420         case ESfunckey:
2421                 vc->vc_state = ESnormal;
2422                 return;
2423         case EShash:
2424                 vc->vc_state = ESnormal;
2425                 if (c == '8') {
2426                         /* DEC screen alignment test. kludge :-) */
2427                         vc->vc_video_erase_char =
2428                                 (vc->vc_video_erase_char & 0xff00) | 'E';
2429                         csi_J(vc, 2);
2430                         vc->vc_video_erase_char =
2431                                 (vc->vc_video_erase_char & 0xff00) | ' ';
2432                         do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
2433                 }
2434                 return;
2435         case ESsetG0:
2436                 if (c == '0')
2437                         vc->vc_G0_charset = GRAF_MAP;
2438                 else if (c == 'B')
2439                         vc->vc_G0_charset = LAT1_MAP;
2440                 else if (c == 'U')
2441                         vc->vc_G0_charset = IBMPC_MAP;
2442                 else if (c == 'K')
2443                         vc->vc_G0_charset = USER_MAP;
2444                 if (vc->vc_charset == 0)
2445                         vc->vc_translate = set_translate(vc->vc_G0_charset, vc);
2446                 vc->vc_state = ESnormal;
2447                 return;
2448         case ESsetG1:
2449                 if (c == '0')
2450                         vc->vc_G1_charset = GRAF_MAP;
2451                 else if (c == 'B')
2452                         vc->vc_G1_charset = LAT1_MAP;
2453                 else if (c == 'U')
2454                         vc->vc_G1_charset = IBMPC_MAP;
2455                 else if (c == 'K')
2456                         vc->vc_G1_charset = USER_MAP;
2457                 if (vc->vc_charset == 1)
2458                         vc->vc_translate = set_translate(vc->vc_G1_charset, vc);
2459                 vc->vc_state = ESnormal;
2460                 return;
2461         case ESosc:
2462                 return;
2463         default:
2464                 vc->vc_state = ESnormal;
2465         }
2466 }
2467
2468 /* is_double_width() is based on the wcwidth() implementation by
2469  * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
2470  * Latest version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
2471  */
2472 struct interval {
2473         uint32_t first;
2474         uint32_t last;
2475 };
2476
2477 static int ucs_cmp(const void *key, const void *elt)
2478 {
2479         uint32_t ucs = *(uint32_t *)key;
2480         struct interval e = *(struct interval *) elt;
2481
2482         if (ucs > e.last)
2483                 return 1;
2484         else if (ucs < e.first)
2485                 return -1;
2486         return 0;
2487 }
2488
2489 static int is_double_width(uint32_t ucs)
2490 {
2491         static const struct interval double_width[] = {
2492                 { 0x1100, 0x115F }, { 0x2329, 0x232A }, { 0x2E80, 0x303E },
2493                 { 0x3040, 0xA4CF }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF },
2494                 { 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 },
2495                 { 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }
2496         };
2497         if (ucs < double_width[0].first ||
2498             ucs > double_width[ARRAY_SIZE(double_width) - 1].last)
2499                 return 0;
2500
2501         return bsearch(&ucs, double_width, ARRAY_SIZE(double_width),
2502                         sizeof(struct interval), ucs_cmp) != NULL;
2503 }
2504
2505 static void con_flush(struct vc_data *vc, unsigned long draw_from,
2506                 unsigned long draw_to, int *draw_x)
2507 {
2508         if (*draw_x < 0)
2509                 return;
2510
2511         vc->vc_sw->con_putcs(vc, (u16 *)draw_from,
2512                         (u16 *)draw_to - (u16 *)draw_from, vc->vc_y, *draw_x);
2513         *draw_x = -1;
2514 }
2515
2516 /* acquires console_lock */
2517 static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int count)
2518 {
2519         int c, next_c, tc, ok, n = 0, draw_x = -1;
2520         unsigned int currcons;
2521         unsigned long draw_from = 0, draw_to = 0;
2522         struct vc_data *vc;
2523         unsigned char vc_attr;
2524         struct vt_notifier_param param;
2525         uint8_t rescan;
2526         uint8_t inverse;
2527         uint8_t width;
2528         u16 himask, charmask;
2529
2530         if (in_interrupt())
2531                 return count;
2532
2533         might_sleep();
2534
2535         console_lock();
2536         vc = tty->driver_data;
2537         if (vc == NULL) {
2538                 pr_err("vt: argh, driver_data is NULL !\n");
2539                 console_unlock();
2540                 return 0;
2541         }
2542
2543         currcons = vc->vc_num;
2544         if (!vc_cons_allocated(currcons)) {
2545                 /* could this happen? */
2546                 pr_warn_once("con_write: tty %d not allocated\n", currcons+1);
2547                 console_unlock();
2548                 return 0;
2549         }
2550
2551         himask = vc->vc_hi_font_mask;
2552         charmask = himask ? 0x1ff : 0xff;
2553
2554         /* undraw cursor first */
2555         if (con_is_fg(vc))
2556                 hide_cursor(vc);
2557
2558         param.vc = vc;
2559
2560         while (!tty->stopped && count) {
2561                 int orig = *buf;
2562                 c = orig;
2563                 buf++;
2564                 n++;
2565                 count--;
2566                 rescan = 0;
2567                 inverse = 0;
2568                 width = 1;
2569
2570                 /* Do no translation at all in control states */
2571                 if (vc->vc_state != ESnormal) {
2572                         tc = c;
2573                 } else if (vc->vc_utf && !vc->vc_disp_ctrl) {
2574                     /* Combine UTF-8 into Unicode in vc_utf_char.
2575                      * vc_utf_count is the number of continuation bytes still
2576                      * expected to arrive.
2577                      * vc_npar is the number of continuation bytes arrived so
2578                      * far
2579                      */
2580 rescan_last_byte:
2581                     if ((c & 0xc0) == 0x80) {
2582                         /* Continuation byte received */
2583                         static const uint32_t utf8_length_changes[] = { 0x0000007f, 0x000007ff, 0x0000ffff, 0x001fffff, 0x03ffffff, 0x7fffffff };
2584                         if (vc->vc_utf_count) {
2585                             vc->vc_utf_char = (vc->vc_utf_char << 6) | (c & 0x3f);
2586                             vc->vc_npar++;
2587                             if (--vc->vc_utf_count) {
2588                                 /* Still need some bytes */
2589                                 continue;
2590                             }
2591                             /* Got a whole character */
2592                             c = vc->vc_utf_char;
2593                             /* Reject overlong sequences */
2594                             if (c <= utf8_length_changes[vc->vc_npar - 1] ||
2595                                         c > utf8_length_changes[vc->vc_npar])
2596                                 c = 0xfffd;
2597                         } else {
2598                             /* Unexpected continuation byte */
2599                             vc->vc_utf_count = 0;
2600                             c = 0xfffd;
2601                         }
2602                     } else {
2603                         /* Single ASCII byte or first byte of a sequence received */
2604                         if (vc->vc_utf_count) {
2605                             /* Continuation byte expected */
2606                             rescan = 1;
2607                             vc->vc_utf_count = 0;
2608                             c = 0xfffd;
2609                         } else if (c > 0x7f) {
2610                             /* First byte of a multibyte sequence received */
2611                             vc->vc_npar = 0;
2612                             if ((c & 0xe0) == 0xc0) {
2613                                 vc->vc_utf_count = 1;
2614                                 vc->vc_utf_char = (c & 0x1f);
2615                             } else if ((c & 0xf0) == 0xe0) {
2616                                 vc->vc_utf_count = 2;
2617                                 vc->vc_utf_char = (c & 0x0f);
2618                             } else if ((c & 0xf8) == 0xf0) {
2619                                 vc->vc_utf_count = 3;
2620                                 vc->vc_utf_char = (c & 0x07);
2621                             } else if ((c & 0xfc) == 0xf8) {
2622                                 vc->vc_utf_count = 4;
2623                                 vc->vc_utf_char = (c & 0x03);
2624                             } else if ((c & 0xfe) == 0xfc) {
2625                                 vc->vc_utf_count = 5;
2626                                 vc->vc_utf_char = (c & 0x01);
2627                             } else {
2628                                 /* 254 and 255 are invalid */
2629                                 c = 0xfffd;
2630                             }
2631                             if (vc->vc_utf_count) {
2632                                 /* Still need some bytes */
2633                                 continue;
2634                             }
2635                         }
2636                         /* Nothing to do if an ASCII byte was received */
2637                     }
2638                     /* End of UTF-8 decoding. */
2639                     /* c is the received character, or U+FFFD for invalid sequences. */
2640                     /* Replace invalid Unicode code points with U+FFFD too */
2641                     if ((c >= 0xd800 && c <= 0xdfff) || c == 0xfffe || c == 0xffff)
2642                         c = 0xfffd;
2643                     tc = c;
2644                 } else {        /* no utf or alternate charset mode */
2645                     tc = vc_translate(vc, c);
2646                 }
2647
2648                 param.c = tc;
2649                 if (atomic_notifier_call_chain(&vt_notifier_list, VT_PREWRITE,
2650                                         &param) == NOTIFY_STOP)
2651                         continue;
2652
2653                 /* If the original code was a control character we
2654                  * only allow a glyph to be displayed if the code is
2655                  * not normally used (such as for cursor movement) or
2656                  * if the disp_ctrl mode has been explicitly enabled.
2657                  * Certain characters (as given by the CTRL_ALWAYS
2658                  * bitmap) are always displayed as control characters,
2659                  * as the console would be pretty useless without
2660                  * them; to display an arbitrary font position use the
2661                  * direct-to-font zone in UTF-8 mode.
2662                  */
2663                 ok = tc && (c >= 32 ||
2664                             !(vc->vc_disp_ctrl ? (CTRL_ALWAYS >> c) & 1 :
2665                                   vc->vc_utf || ((CTRL_ACTION >> c) & 1)))
2666                         && (c != 127 || vc->vc_disp_ctrl)
2667                         && (c != 128+27);
2668
2669                 if (vc->vc_state == ESnormal && ok) {
2670                         if (vc->vc_utf && !vc->vc_disp_ctrl) {
2671                                 if (is_double_width(c))
2672                                         width = 2;
2673                         }
2674                         /* Now try to find out how to display it */
2675                         tc = conv_uni_to_pc(vc, tc);
2676                         if (tc & ~charmask) {
2677                                 if (tc == -1 || tc == -2) {
2678                                     continue; /* nothing to display */
2679                                 }
2680                                 /* Glyph not found */
2681                                 if ((!(vc->vc_utf && !vc->vc_disp_ctrl) || c < 128) && !(c & ~charmask)) {
2682                                     /* In legacy mode use the glyph we get by a 1:1 mapping.
2683                                        This would make absolutely no sense with Unicode in mind,
2684                                        but do this for ASCII characters since a font may lack
2685                                        Unicode mapping info and we don't want to end up with
2686                                        having question marks only. */
2687                                     tc = c;
2688                                 } else {
2689                                     /* Display U+FFFD. If it's not found, display an inverse question mark. */
2690                                     tc = conv_uni_to_pc(vc, 0xfffd);
2691                                     if (tc < 0) {
2692                                         inverse = 1;
2693                                         tc = conv_uni_to_pc(vc, '?');
2694                                         if (tc < 0) tc = '?';
2695                                     }
2696                                 }
2697                         }
2698
2699                         if (!inverse) {
2700                                 vc_attr = vc->vc_attr;
2701                         } else {
2702                                 /* invert vc_attr */
2703                                 if (!vc->vc_can_do_color) {
2704                                         vc_attr = (vc->vc_attr) ^ 0x08;
2705                                 } else if (vc->vc_hi_font_mask == 0x100) {
2706                                         vc_attr = ((vc->vc_attr) & 0x11) | (((vc->vc_attr) & 0xe0) >> 4) | (((vc->vc_attr) & 0x0e) << 4);
2707                                 } else {
2708                                         vc_attr = ((vc->vc_attr) & 0x88) | (((vc->vc_attr) & 0x70) >> 4) | (((vc->vc_attr) & 0x07) << 4);
2709                                 }
2710                                 con_flush(vc, draw_from, draw_to, &draw_x);
2711                         }
2712
2713                         next_c = c;
2714                         while (1) {
2715                                 if (vc->vc_need_wrap || vc->vc_decim)
2716                                         con_flush(vc, draw_from, draw_to,
2717                                                         &draw_x);
2718                                 if (vc->vc_need_wrap) {
2719                                         cr(vc);
2720                                         lf(vc);
2721                                 }
2722                                 if (vc->vc_decim)
2723                                         insert_char(vc, 1);
2724                                 vc_uniscr_putc(vc, next_c);
2725                                 scr_writew(himask ?
2726                                              ((vc_attr << 8) & ~himask) + ((tc & 0x100) ? himask : 0) + (tc & 0xff) :
2727                                              (vc_attr << 8) + tc,
2728                                            (u16 *) vc->vc_pos);
2729                                 if (con_should_update(vc) && draw_x < 0) {
2730                                         draw_x = vc->vc_x;
2731                                         draw_from = vc->vc_pos;
2732                                 }
2733                                 if (vc->vc_x == vc->vc_cols - 1) {
2734                                         vc->vc_need_wrap = vc->vc_decawm;
2735                                         draw_to = vc->vc_pos + 2;
2736                                 } else {
2737                                         vc->vc_x++;
2738                                         draw_to = (vc->vc_pos += 2);
2739                                 }
2740
2741                                 if (!--width) break;
2742
2743                                 tc = conv_uni_to_pc(vc, ' '); /* A space is printed in the second column */
2744                                 if (tc < 0) tc = ' ';
2745                                 next_c = ' ';
2746                         }
2747                         notify_write(vc, c);
2748
2749                         if (inverse)
2750                                 con_flush(vc, draw_from, draw_to, &draw_x);
2751
2752                         if (rescan) {
2753                                 rescan = 0;
2754                                 inverse = 0;
2755                                 width = 1;
2756                                 c = orig;
2757                                 goto rescan_last_byte;
2758                         }
2759                         continue;
2760                 }
2761                 con_flush(vc, draw_from, draw_to, &draw_x);
2762                 do_con_trol(tty, vc, orig);
2763         }
2764         con_flush(vc, draw_from, draw_to, &draw_x);
2765         vc_uniscr_debug_check(vc);
2766         console_conditional_schedule();
2767         console_unlock();
2768         notify_update(vc);
2769         return n;
2770 }
2771
2772 /*
2773  * This is the console switching callback.
2774  *
2775  * Doing console switching in a process context allows
2776  * us to do the switches asynchronously (needed when we want
2777  * to switch due to a keyboard interrupt).  Synchronization
2778  * with other console code and prevention of re-entrancy is
2779  * ensured with console_lock.
2780  */
2781 static void console_callback(struct work_struct *ignored)
2782 {
2783         console_lock();
2784
2785         if (want_console >= 0) {
2786                 if (want_console != fg_console &&
2787                     vc_cons_allocated(want_console)) {
2788                         hide_cursor(vc_cons[fg_console].d);
2789                         change_console(vc_cons[want_console].d);
2790                         /* we only changed when the console had already
2791                            been allocated - a new console is not created
2792                            in an interrupt routine */
2793                 }
2794                 want_console = -1;
2795         }
2796         if (do_poke_blanked_console) { /* do not unblank for a LED change */
2797                 do_poke_blanked_console = 0;
2798                 poke_blanked_console();
2799         }
2800         if (scrollback_delta) {
2801                 struct vc_data *vc = vc_cons[fg_console].d;
2802                 clear_selection();
2803                 if (vc->vc_mode == KD_TEXT && vc->vc_sw->con_scrolldelta)
2804                         vc->vc_sw->con_scrolldelta(vc, scrollback_delta);
2805                 scrollback_delta = 0;
2806         }
2807         if (blank_timer_expired) {
2808                 do_blank_screen(0);
2809                 blank_timer_expired = 0;
2810         }
2811         notify_update(vc_cons[fg_console].d);
2812
2813         console_unlock();
2814 }
2815
2816 int set_console(int nr)
2817 {
2818         struct vc_data *vc = vc_cons[fg_console].d;
2819
2820         if (!vc_cons_allocated(nr) || vt_dont_switch ||
2821                 (vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) {
2822
2823                 /*
2824                  * Console switch will fail in console_callback() or
2825                  * change_console() so there is no point scheduling
2826                  * the callback
2827                  *
2828                  * Existing set_console() users don't check the return
2829                  * value so this shouldn't break anything
2830                  */
2831                 return -EINVAL;
2832         }
2833
2834         want_console = nr;
2835         schedule_console_callback();
2836
2837         return 0;
2838 }
2839
2840 struct tty_driver *console_driver;
2841
2842 #ifdef CONFIG_VT_CONSOLE
2843
2844 /**
2845  * vt_kmsg_redirect() - Sets/gets the kernel message console
2846  * @new:        The new virtual terminal number or -1 if the console should stay
2847  *              unchanged
2848  *
2849  * By default, the kernel messages are always printed on the current virtual
2850  * console. However, the user may modify that default with the
2851  * TIOCL_SETKMSGREDIRECT ioctl call.
2852  *
2853  * This function sets the kernel message console to be @new. It returns the old
2854  * virtual console number. The virtual terminal number 0 (both as parameter and
2855  * return value) means no redirection (i.e. always printed on the currently
2856  * active console).
2857  *
2858  * The parameter -1 means that only the current console is returned, but the
2859  * value is not modified. You may use the macro vt_get_kmsg_redirect() in that
2860  * case to make the code more understandable.
2861  *
2862  * When the kernel is compiled without CONFIG_VT_CONSOLE, this function ignores
2863  * the parameter and always returns 0.
2864  */
2865 int vt_kmsg_redirect(int new)
2866 {
2867         static int kmsg_con;
2868
2869         if (new != -1)
2870                 return xchg(&kmsg_con, new);
2871         else
2872                 return kmsg_con;
2873 }
2874
2875 /*
2876  *      Console on virtual terminal
2877  *
2878  * The console must be locked when we get here.
2879  */
2880
2881 static void vt_console_print(struct console *co, const char *b, unsigned count)
2882 {
2883         struct vc_data *vc = vc_cons[fg_console].d;
2884         unsigned char c;
2885         static DEFINE_SPINLOCK(printing_lock);
2886         const ushort *start;
2887         ushort cnt = 0;
2888         ushort myx;
2889         int kmsg_console;
2890
2891         /* console busy or not yet initialized */
2892         if (!printable)
2893                 return;
2894         if (!spin_trylock(&printing_lock))
2895                 return;
2896
2897         kmsg_console = vt_get_kmsg_redirect();
2898         if (kmsg_console && vc_cons_allocated(kmsg_console - 1))
2899                 vc = vc_cons[kmsg_console - 1].d;
2900
2901         /* read `x' only after setting currcons properly (otherwise
2902            the `x' macro will read the x of the foreground console). */
2903         myx = vc->vc_x;
2904
2905         if (!vc_cons_allocated(fg_console)) {
2906                 /* impossible */
2907                 /* printk("vt_console_print: tty %d not allocated ??\n", currcons+1); */
2908                 goto quit;
2909         }
2910
2911         if (vc->vc_mode != KD_TEXT)
2912                 goto quit;
2913
2914         /* undraw cursor first */
2915         if (con_is_fg(vc))
2916                 hide_cursor(vc);
2917
2918         start = (ushort *)vc->vc_pos;
2919
2920         /* Contrived structure to try to emulate original need_wrap behaviour
2921          * Problems caused when we have need_wrap set on '\n' character */
2922         while (count--) {
2923                 c = *b++;
2924                 if (c == 10 || c == 13 || c == 8 || vc->vc_need_wrap) {
2925                         if (cnt > 0) {
2926                                 if (con_is_visible(vc))
2927                                         vc->vc_sw->con_putcs(vc, start, cnt, vc->vc_y, vc->vc_x);
2928                                 vc->vc_x += cnt;
2929                                 if (vc->vc_need_wrap)
2930                                         vc->vc_x--;
2931                                 cnt = 0;
2932                         }
2933                         if (c == 8) {           /* backspace */
2934                                 bs(vc);
2935                                 start = (ushort *)vc->vc_pos;
2936                                 myx = vc->vc_x;
2937                                 continue;
2938                         }
2939                         if (c != 13)
2940                                 lf(vc);
2941                         cr(vc);
2942                         start = (ushort *)vc->vc_pos;
2943                         myx = vc->vc_x;
2944                         if (c == 10 || c == 13)
2945                                 continue;
2946                 }
2947                 scr_writew((vc->vc_attr << 8) + c, (unsigned short *)vc->vc_pos);
2948                 notify_write(vc, c);
2949                 cnt++;
2950                 if (myx == vc->vc_cols - 1) {
2951                         vc->vc_need_wrap = 1;
2952                         continue;
2953                 }
2954                 vc->vc_pos += 2;
2955                 myx++;
2956         }
2957         if (cnt > 0) {
2958                 if (con_is_visible(vc))
2959                         vc->vc_sw->con_putcs(vc, start, cnt, vc->vc_y, vc->vc_x);
2960                 vc->vc_x += cnt;
2961                 if (vc->vc_x == vc->vc_cols) {
2962                         vc->vc_x--;
2963                         vc->vc_need_wrap = 1;
2964                 }
2965         }
2966         set_cursor(vc);
2967         notify_update(vc);
2968
2969 quit:
2970         spin_unlock(&printing_lock);
2971 }
2972
2973 static struct tty_driver *vt_console_device(struct console *c, int *index)
2974 {
2975         *index = c->index ? c->index-1 : fg_console;
2976         return console_driver;
2977 }
2978
2979 static struct console vt_console_driver = {
2980         .name           = "tty",
2981         .write          = vt_console_print,
2982         .device         = vt_console_device,
2983         .unblank        = unblank_screen,
2984         .flags          = CON_PRINTBUFFER,
2985         .index          = -1,
2986 };
2987 #endif
2988
2989 /*
2990  *      Handling of Linux-specific VC ioctls
2991  */
2992
2993 /*
2994  * Generally a bit racy with respect to console_lock();.
2995  *
2996  * There are some functions which don't need it.
2997  *
2998  * There are some functions which can sleep for arbitrary periods
2999  * (paste_selection) but we don't need the lock there anyway.
3000  *
3001  * set_selection has locking, and definitely needs it
3002  */
3003
3004 int tioclinux(struct tty_struct *tty, unsigned long arg)
3005 {
3006         char type, data;
3007         char __user *p = (char __user *)arg;
3008         int lines;
3009         int ret;
3010
3011         if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
3012                 return -EPERM;
3013         if (get_user(type, p))
3014                 return -EFAULT;
3015         ret = 0;
3016
3017         switch (type)
3018         {
3019                 case TIOCL_SETSEL:
3020                         console_lock();
3021                         ret = set_selection((struct tiocl_selection __user *)(p+1), tty);
3022                         console_unlock();
3023                         break;
3024                 case TIOCL_PASTESEL:
3025                         ret = paste_selection(tty);
3026                         break;
3027                 case TIOCL_UNBLANKSCREEN:
3028                         console_lock();
3029                         unblank_screen();
3030                         console_unlock();
3031                         break;
3032                 case TIOCL_SELLOADLUT:
3033                         console_lock();
3034                         ret = sel_loadlut(p);
3035                         console_unlock();
3036                         break;
3037                 case TIOCL_GETSHIFTSTATE:
3038
3039         /*
3040          * Make it possible to react to Shift+Mousebutton.
3041          * Note that 'shift_state' is an undocumented
3042          * kernel-internal variable; programs not closely
3043          * related to the kernel should not use this.
3044          */
3045                         data = vt_get_shift_state();
3046                         ret = put_user(data, p);
3047                         break;
3048                 case TIOCL_GETMOUSEREPORTING:
3049                         console_lock(); /* May be overkill */
3050                         data = mouse_reporting();
3051                         console_unlock();
3052                         ret = put_user(data, p);
3053                         break;
3054                 case TIOCL_SETVESABLANK:
3055                         console_lock();
3056                         ret = set_vesa_blanking(p);
3057                         console_unlock();
3058                         break;
3059                 case TIOCL_GETKMSGREDIRECT:
3060                         data = vt_get_kmsg_redirect();
3061                         ret = put_user(data, p);
3062                         break;
3063                 case TIOCL_SETKMSGREDIRECT:
3064                         if (!capable(CAP_SYS_ADMIN)) {
3065                                 ret = -EPERM;
3066                         } else {
3067                                 if (get_user(data, p+1))
3068                                         ret = -EFAULT;
3069                                 else
3070                                         vt_kmsg_redirect(data);
3071                         }
3072                         break;
3073                 case TIOCL_GETFGCONSOLE:
3074                         /* No locking needed as this is a transiently
3075                            correct return anyway if the caller hasn't
3076                            disabled switching */
3077                         ret = fg_console;
3078                         break;
3079                 case TIOCL_SCROLLCONSOLE:
3080                         if (get_user(lines, (s32 __user *)(p+4))) {
3081                                 ret = -EFAULT;
3082                         } else {
3083                                 /* Need the console lock here. Note that lots
3084                                    of other calls need fixing before the lock
3085                                    is actually useful ! */
3086                                 console_lock();
3087                                 scrollfront(vc_cons[fg_console].d, lines);
3088                                 console_unlock();
3089                                 ret = 0;
3090                         }
3091                         break;
3092                 case TIOCL_BLANKSCREEN: /* until explicitly unblanked, not only poked */
3093                         console_lock();
3094                         ignore_poke = 1;
3095                         do_blank_screen(0);
3096                         console_unlock();
3097                         break;
3098                 case TIOCL_BLANKEDSCREEN:
3099                         ret = console_blanked;
3100                         break;
3101                 default:
3102                         ret = -EINVAL;
3103                         break;
3104         }
3105         return ret;
3106 }
3107
3108 /*
3109  * /dev/ttyN handling
3110  */
3111
3112 static int con_write(struct tty_struct *tty, const unsigned char *buf, int count)
3113 {
3114         int     retval;
3115
3116         retval = do_con_write(tty, buf, count);
3117         con_flush_chars(tty);
3118
3119         return retval;
3120 }
3121
3122 static int con_put_char(struct tty_struct *tty, unsigned char ch)
3123 {
3124         if (in_interrupt())
3125                 return 0;       /* n_r3964 calls put_char() from interrupt context */
3126         return do_con_write(tty, &ch, 1);
3127 }
3128
3129 static int con_write_room(struct tty_struct *tty)
3130 {
3131         if (tty->stopped)
3132                 return 0;
3133         return 32768;           /* No limit, really; we're not buffering */
3134 }
3135
3136 static int con_chars_in_buffer(struct tty_struct *tty)
3137 {
3138         return 0;               /* we're not buffering */
3139 }
3140
3141 /*
3142  * con_throttle and con_unthrottle are only used for
3143  * paste_selection(), which has to stuff in a large number of
3144  * characters...
3145  */
3146 static void con_throttle(struct tty_struct *tty)
3147 {
3148 }
3149
3150 static void con_unthrottle(struct tty_struct *tty)
3151 {
3152         struct vc_data *vc = tty->driver_data;
3153
3154         wake_up_interruptible(&vc->paste_wait);
3155 }
3156
3157 /*
3158  * Turn the Scroll-Lock LED on when the tty is stopped
3159  */
3160 static void con_stop(struct tty_struct *tty)
3161 {
3162         int console_num;
3163         if (!tty)
3164                 return;
3165         console_num = tty->index;
3166         if (!vc_cons_allocated(console_num))
3167                 return;
3168         vt_kbd_con_stop(console_num);
3169 }
3170
3171 /*
3172  * Turn the Scroll-Lock LED off when the console is started
3173  */
3174 static void con_start(struct tty_struct *tty)
3175 {
3176         int console_num;
3177         if (!tty)
3178                 return;
3179         console_num = tty->index;
3180         if (!vc_cons_allocated(console_num))
3181                 return;
3182         vt_kbd_con_start(console_num);
3183 }
3184
3185 static void con_flush_chars(struct tty_struct *tty)
3186 {
3187         struct vc_data *vc;
3188
3189         if (in_interrupt())     /* from flush_to_ldisc */
3190                 return;
3191
3192         /* if we race with con_close(), vt may be null */
3193         console_lock();
3194         vc = tty->driver_data;
3195         if (vc)
3196                 set_cursor(vc);
3197         console_unlock();
3198 }
3199
3200 /*
3201  * Allocate the console screen memory.
3202  */
3203 static int con_install(struct tty_driver *driver, struct tty_struct *tty)
3204 {
3205         unsigned int currcons = tty->index;
3206         struct vc_data *vc;
3207         int ret;
3208
3209         console_lock();
3210         ret = vc_allocate(currcons);
3211         if (ret)
3212                 goto unlock;
3213
3214         vc = vc_cons[currcons].d;
3215
3216         /* Still being freed */
3217         if (vc->port.tty) {
3218                 ret = -ERESTARTSYS;
3219                 goto unlock;
3220         }
3221
3222         ret = tty_port_install(&vc->port, driver, tty);
3223         if (ret)
3224                 goto unlock;
3225
3226         tty->driver_data = vc;
3227         vc->port.tty = tty;
3228
3229         if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
3230                 tty->winsize.ws_row = vc_cons[currcons].d->vc_rows;
3231                 tty->winsize.ws_col = vc_cons[currcons].d->vc_cols;
3232         }
3233         if (vc->vc_utf)
3234                 tty->termios.c_iflag |= IUTF8;
3235         else
3236                 tty->termios.c_iflag &= ~IUTF8;
3237 unlock:
3238         console_unlock();
3239         return ret;
3240 }
3241
3242 static int con_open(struct tty_struct *tty, struct file *filp)
3243 {
3244         /* everything done in install */
3245         return 0;
3246 }
3247
3248
3249 static void con_close(struct tty_struct *tty, struct file *filp)
3250 {
3251         /* Nothing to do - we defer to shutdown */
3252 }
3253
3254 static void con_shutdown(struct tty_struct *tty)
3255 {
3256         struct vc_data *vc = tty->driver_data;
3257         BUG_ON(vc == NULL);
3258         console_lock();
3259         vc->port.tty = NULL;
3260         console_unlock();
3261 }
3262
3263 static int default_color           = 7; /* white */
3264 static int default_italic_color    = 2; // green (ASCII)
3265 static int default_underline_color = 3; // cyan (ASCII)
3266 module_param_named(color, default_color, int, S_IRUGO | S_IWUSR);
3267 module_param_named(italic, default_italic_color, int, S_IRUGO | S_IWUSR);
3268 module_param_named(underline, default_underline_color, int, S_IRUGO | S_IWUSR);
3269
3270 static void vc_init(struct vc_data *vc, unsigned int rows,
3271                     unsigned int cols, int do_clear)
3272 {
3273         int j, k ;
3274
3275         vc->vc_cols = cols;
3276         vc->vc_rows = rows;
3277         vc->vc_size_row = cols << 1;
3278         vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
3279
3280         set_origin(vc);
3281         vc->vc_pos = vc->vc_origin;
3282         reset_vc(vc);
3283         for (j=k=0; j<16; j++) {
3284                 vc->vc_palette[k++] = default_red[j] ;
3285                 vc->vc_palette[k++] = default_grn[j] ;
3286                 vc->vc_palette[k++] = default_blu[j] ;
3287         }
3288         vc->vc_def_color       = default_color;
3289         vc->vc_ulcolor         = default_underline_color;
3290         vc->vc_itcolor         = default_italic_color;
3291         vc->vc_halfcolor       = 0x08;   /* grey */
3292         init_waitqueue_head(&vc->paste_wait);
3293         reset_terminal(vc, do_clear);
3294 }
3295
3296 /*
3297  * This routine initializes console interrupts, and does nothing
3298  * else. If you want the screen to clear, call tty_write with
3299  * the appropriate escape-sequence.
3300  */
3301
3302 static int __init con_init(void)
3303 {
3304         const char *display_desc = NULL;
3305         struct vc_data *vc;
3306         unsigned int currcons = 0, i;
3307
3308         console_lock();
3309
3310         if (conswitchp)
3311                 display_desc = conswitchp->con_startup();
3312         if (!display_desc) {
3313                 fg_console = 0;
3314                 console_unlock();
3315                 return 0;
3316         }
3317
3318         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3319                 struct con_driver *con_driver = &registered_con_driver[i];
3320
3321                 if (con_driver->con == NULL) {
3322                         con_driver->con = conswitchp;
3323                         con_driver->desc = display_desc;
3324                         con_driver->flag = CON_DRIVER_FLAG_INIT;
3325                         con_driver->first = 0;
3326                         con_driver->last = MAX_NR_CONSOLES - 1;
3327                         break;
3328                 }
3329         }
3330
3331         for (i = 0; i < MAX_NR_CONSOLES; i++)
3332                 con_driver_map[i] = conswitchp;
3333
3334         if (blankinterval) {
3335                 blank_state = blank_normal_wait;
3336                 mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3337         }
3338
3339         for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) {
3340                 vc_cons[currcons].d = vc = kzalloc(sizeof(struct vc_data), GFP_NOWAIT);
3341                 INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
3342                 tty_port_init(&vc->port);
3343                 visual_init(vc, currcons, 1);
3344                 vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_NOWAIT);
3345                 vc_init(vc, vc->vc_rows, vc->vc_cols,
3346                         currcons || !vc->vc_sw->con_save_screen);
3347         }
3348         currcons = fg_console = 0;
3349         master_display_fg = vc = vc_cons[currcons].d;
3350         set_origin(vc);
3351         save_screen(vc);
3352         gotoxy(vc, vc->vc_x, vc->vc_y);
3353         csi_J(vc, 0);
3354         update_screen(vc);
3355         pr_info("Console: %s %s %dx%d\n",
3356                 vc->vc_can_do_color ? "colour" : "mono",
3357                 display_desc, vc->vc_cols, vc->vc_rows);
3358         printable = 1;
3359
3360         console_unlock();
3361
3362 #ifdef CONFIG_VT_CONSOLE
3363         register_console(&vt_console_driver);
3364 #endif
3365         return 0;
3366 }
3367 console_initcall(con_init);
3368
3369 static const struct tty_operations con_ops = {
3370         .install = con_install,
3371         .open = con_open,
3372         .close = con_close,
3373         .write = con_write,
3374         .write_room = con_write_room,
3375         .put_char = con_put_char,
3376         .flush_chars = con_flush_chars,
3377         .chars_in_buffer = con_chars_in_buffer,
3378         .ioctl = vt_ioctl,
3379 #ifdef CONFIG_COMPAT
3380         .compat_ioctl = vt_compat_ioctl,
3381 #endif
3382         .stop = con_stop,
3383         .start = con_start,
3384         .throttle = con_throttle,
3385         .unthrottle = con_unthrottle,
3386         .resize = vt_resize,
3387         .shutdown = con_shutdown
3388 };
3389
3390 static struct cdev vc0_cdev;
3391
3392 static ssize_t show_tty_active(struct device *dev,
3393                                 struct device_attribute *attr, char *buf)
3394 {
3395         return sprintf(buf, "tty%d\n", fg_console + 1);
3396 }
3397 static DEVICE_ATTR(active, S_IRUGO, show_tty_active, NULL);
3398
3399 static struct attribute *vt_dev_attrs[] = {
3400         &dev_attr_active.attr,
3401         NULL
3402 };
3403
3404 ATTRIBUTE_GROUPS(vt_dev);
3405
3406 int __init vty_init(const struct file_operations *console_fops)
3407 {
3408         cdev_init(&vc0_cdev, console_fops);
3409         if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
3410             register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
3411                 panic("Couldn't register /dev/tty0 driver\n");
3412         tty0dev = device_create_with_groups(tty_class, NULL,
3413                                             MKDEV(TTY_MAJOR, 0), NULL,
3414                                             vt_dev_groups, "tty0");
3415         if (IS_ERR(tty0dev))
3416                 tty0dev = NULL;
3417
3418         vcs_init();
3419
3420         console_driver = alloc_tty_driver(MAX_NR_CONSOLES);
3421         if (!console_driver)
3422                 panic("Couldn't allocate console driver\n");
3423
3424         console_driver->name = "tty";
3425         console_driver->name_base = 1;
3426         console_driver->major = TTY_MAJOR;
3427         console_driver->minor_start = 1;
3428         console_driver->type = TTY_DRIVER_TYPE_CONSOLE;
3429         console_driver->init_termios = tty_std_termios;
3430         if (default_utf8)
3431                 console_driver->init_termios.c_iflag |= IUTF8;
3432         console_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS;
3433         tty_set_operations(console_driver, &con_ops);
3434         if (tty_register_driver(console_driver))
3435                 panic("Couldn't register console driver\n");
3436         kbd_init();
3437         console_map_init();
3438 #ifdef CONFIG_MDA_CONSOLE
3439         mda_console_init();
3440 #endif
3441         return 0;
3442 }
3443
3444 #ifndef VT_SINGLE_DRIVER
3445
3446 static struct class *vtconsole_class;
3447
3448 static int do_bind_con_driver(const struct consw *csw, int first, int last,
3449                            int deflt)
3450 {
3451         struct module *owner = csw->owner;
3452         const char *desc = NULL;
3453         struct con_driver *con_driver;
3454         int i, j = -1, k = -1, retval = -ENODEV;
3455
3456         if (!try_module_get(owner))
3457                 return -ENODEV;
3458
3459         WARN_CONSOLE_UNLOCKED();
3460
3461         /* check if driver is registered */
3462         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3463                 con_driver = &registered_con_driver[i];
3464
3465                 if (con_driver->con == csw) {
3466                         desc = con_driver->desc;
3467                         retval = 0;
3468                         break;
3469                 }
3470         }
3471
3472         if (retval)
3473                 goto err;
3474
3475         if (!(con_driver->flag & CON_DRIVER_FLAG_INIT)) {
3476                 csw->con_startup();
3477                 con_driver->flag |= CON_DRIVER_FLAG_INIT;
3478         }
3479
3480         if (deflt) {
3481                 if (conswitchp)
3482                         module_put(conswitchp->owner);
3483
3484                 __module_get(owner);
3485                 conswitchp = csw;
3486         }
3487
3488         first = max(first, con_driver->first);
3489         last = min(last, con_driver->last);
3490
3491         for (i = first; i <= last; i++) {
3492                 int old_was_color;
3493                 struct vc_data *vc = vc_cons[i].d;
3494
3495                 if (con_driver_map[i])
3496                         module_put(con_driver_map[i]->owner);
3497                 __module_get(owner);
3498                 con_driver_map[i] = csw;
3499
3500                 if (!vc || !vc->vc_sw)
3501                         continue;
3502
3503                 j = i;
3504
3505                 if (con_is_visible(vc)) {
3506                         k = i;
3507                         save_screen(vc);
3508                 }
3509
3510                 old_was_color = vc->vc_can_do_color;
3511                 vc->vc_sw->con_deinit(vc);
3512                 vc->vc_origin = (unsigned long)vc->vc_screenbuf;
3513                 visual_init(vc, i, 0);
3514                 set_origin(vc);
3515                 update_attr(vc);
3516
3517                 /* If the console changed between mono <-> color, then
3518                  * the attributes in the screenbuf will be wrong.  The
3519                  * following resets all attributes to something sane.
3520                  */
3521                 if (old_was_color != vc->vc_can_do_color)
3522                         clear_buffer_attributes(vc);
3523         }
3524
3525         pr_info("Console: switching ");
3526         if (!deflt)
3527                 pr_cont("consoles %d-%d ", first + 1, last + 1);
3528         if (j >= 0) {
3529                 struct vc_data *vc = vc_cons[j].d;
3530
3531                 pr_cont("to %s %s %dx%d\n",
3532                         vc->vc_can_do_color ? "colour" : "mono",
3533                         desc, vc->vc_cols, vc->vc_rows);
3534
3535                 if (k >= 0) {
3536                         vc = vc_cons[k].d;
3537                         update_screen(vc);
3538                 }
3539         } else {
3540                 pr_cont("to %s\n", desc);
3541         }
3542
3543         retval = 0;
3544 err:
3545         module_put(owner);
3546         return retval;
3547 };
3548
3549
3550 #ifdef CONFIG_VT_HW_CONSOLE_BINDING
3551 /* unlocked version of unbind_con_driver() */
3552 int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
3553 {
3554         struct module *owner = csw->owner;
3555         const struct consw *defcsw = NULL;
3556         struct con_driver *con_driver = NULL, *con_back = NULL;
3557         int i, retval = -ENODEV;
3558
3559         if (!try_module_get(owner))
3560                 return -ENODEV;
3561
3562         WARN_CONSOLE_UNLOCKED();
3563
3564         /* check if driver is registered and if it is unbindable */
3565         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3566                 con_driver = &registered_con_driver[i];
3567
3568                 if (con_driver->con == csw &&
3569                     con_driver->flag & CON_DRIVER_FLAG_MODULE) {
3570                         retval = 0;
3571                         break;
3572                 }
3573         }
3574
3575         if (retval)
3576                 goto err;
3577
3578         retval = -ENODEV;
3579
3580         /* check if backup driver exists */
3581         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3582                 con_back = &registered_con_driver[i];
3583
3584                 if (con_back->con && con_back->con != csw) {
3585                         defcsw = con_back->con;
3586                         retval = 0;
3587                         break;
3588                 }
3589         }
3590
3591         if (retval)
3592                 goto err;
3593
3594         if (!con_is_bound(csw))
3595                 goto err;
3596
3597         first = max(first, con_driver->first);
3598         last = min(last, con_driver->last);
3599
3600         for (i = first; i <= last; i++) {
3601                 if (con_driver_map[i] == csw) {
3602                         module_put(csw->owner);
3603                         con_driver_map[i] = NULL;
3604                 }
3605         }
3606
3607         if (!con_is_bound(defcsw)) {
3608                 const struct consw *defconsw = conswitchp;
3609
3610                 defcsw->con_startup();
3611                 con_back->flag |= CON_DRIVER_FLAG_INIT;
3612                 /*
3613                  * vgacon may change the default driver to point
3614                  * to dummycon, we restore it here...
3615                  */
3616                 conswitchp = defconsw;
3617         }
3618
3619         if (!con_is_bound(csw))
3620                 con_driver->flag &= ~CON_DRIVER_FLAG_INIT;
3621
3622         /* ignore return value, binding should not fail */
3623         do_bind_con_driver(defcsw, first, last, deflt);
3624 err:
3625         module_put(owner);
3626         return retval;
3627
3628 }
3629 EXPORT_SYMBOL_GPL(do_unbind_con_driver);
3630
3631 static int vt_bind(struct con_driver *con)
3632 {
3633         const struct consw *defcsw = NULL, *csw = NULL;
3634         int i, more = 1, first = -1, last = -1, deflt = 0;
3635
3636         if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3637                 goto err;
3638
3639         csw = con->con;
3640
3641         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3642                 struct con_driver *con = &registered_con_driver[i];
3643
3644                 if (con->con && !(con->flag & CON_DRIVER_FLAG_MODULE)) {
3645                         defcsw = con->con;
3646                         break;
3647                 }
3648         }
3649
3650         if (!defcsw)
3651                 goto err;
3652
3653         while (more) {
3654                 more = 0;
3655
3656                 for (i = con->first; i <= con->last; i++) {
3657                         if (con_driver_map[i] == defcsw) {
3658                                 if (first == -1)
3659                                         first = i;
3660                                 last = i;
3661                                 more = 1;
3662                         } else if (first != -1)
3663                                 break;
3664                 }
3665
3666                 if (first == 0 && last == MAX_NR_CONSOLES -1)
3667                         deflt = 1;
3668
3669                 if (first != -1)
3670                         do_bind_con_driver(csw, first, last, deflt);
3671
3672                 first = -1;
3673                 last = -1;
3674                 deflt = 0;
3675         }
3676
3677 err:
3678         return 0;
3679 }
3680
3681 static int vt_unbind(struct con_driver *con)
3682 {
3683         const struct consw *csw = NULL;
3684         int i, more = 1, first = -1, last = -1, deflt = 0;
3685         int ret;
3686
3687         if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3688                 goto err;
3689
3690         csw = con->con;
3691
3692         while (more) {
3693                 more = 0;
3694
3695                 for (i = con->first; i <= con->last; i++) {
3696                         if (con_driver_map[i] == csw) {
3697                                 if (first == -1)
3698                                         first = i;
3699                                 last = i;
3700                                 more = 1;
3701                         } else if (first != -1)
3702                                 break;
3703                 }
3704
3705                 if (first == 0 && last == MAX_NR_CONSOLES -1)
3706                         deflt = 1;
3707
3708                 if (first != -1) {
3709                         ret = do_unbind_con_driver(csw, first, last, deflt);
3710                         if (ret != 0)
3711                                 return ret;
3712                 }
3713
3714                 first = -1;
3715                 last = -1;
3716                 deflt = 0;
3717         }
3718
3719 err:
3720         return 0;
3721 }
3722 #else
3723 static inline int vt_bind(struct con_driver *con)
3724 {
3725         return 0;
3726 }
3727 static inline int vt_unbind(struct con_driver *con)
3728 {
3729         return 0;
3730 }
3731 #endif /* CONFIG_VT_HW_CONSOLE_BINDING */
3732
3733 static ssize_t store_bind(struct device *dev, struct device_attribute *attr,
3734                           const char *buf, size_t count)
3735 {
3736         struct con_driver *con = dev_get_drvdata(dev);
3737         int bind = simple_strtoul(buf, NULL, 0);
3738
3739         console_lock();
3740
3741         if (bind)
3742                 vt_bind(con);
3743         else
3744                 vt_unbind(con);
3745
3746         console_unlock();
3747
3748         return count;
3749 }
3750
3751 static ssize_t show_bind(struct device *dev, struct device_attribute *attr,
3752                          char *buf)
3753 {
3754         struct con_driver *con = dev_get_drvdata(dev);
3755         int bind = con_is_bound(con->con);
3756
3757         return snprintf(buf, PAGE_SIZE, "%i\n", bind);
3758 }
3759
3760 static ssize_t show_name(struct device *dev, struct device_attribute *attr,
3761                          char *buf)
3762 {
3763         struct con_driver *con = dev_get_drvdata(dev);
3764
3765         return snprintf(buf, PAGE_SIZE, "%s %s\n",
3766                         (con->flag & CON_DRIVER_FLAG_MODULE) ? "(M)" : "(S)",
3767                          con->desc);
3768
3769 }
3770
3771 static DEVICE_ATTR(bind, S_IRUGO|S_IWUSR, show_bind, store_bind);
3772 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
3773
3774 static struct attribute *con_dev_attrs[] = {
3775         &dev_attr_bind.attr,
3776         &dev_attr_name.attr,
3777         NULL
3778 };
3779
3780 ATTRIBUTE_GROUPS(con_dev);
3781
3782 static int vtconsole_init_device(struct con_driver *con)
3783 {
3784         con->flag |= CON_DRIVER_FLAG_ATTR;
3785         return 0;
3786 }
3787
3788 static void vtconsole_deinit_device(struct con_driver *con)
3789 {
3790         con->flag &= ~CON_DRIVER_FLAG_ATTR;
3791 }
3792
3793 /**
3794  * con_is_bound - checks if driver is bound to the console
3795  * @csw: console driver
3796  *
3797  * RETURNS: zero if unbound, nonzero if bound
3798  *
3799  * Drivers can call this and if zero, they should release
3800  * all resources allocated on con_startup()
3801  */
3802 int con_is_bound(const struct consw *csw)
3803 {
3804         int i, bound = 0;
3805
3806         for (i = 0; i < MAX_NR_CONSOLES; i++) {
3807                 if (con_driver_map[i] == csw) {
3808                         bound = 1;
3809                         break;
3810                 }
3811         }
3812
3813         return bound;
3814 }
3815 EXPORT_SYMBOL(con_is_bound);
3816
3817 /**
3818  * con_debug_enter - prepare the console for the kernel debugger
3819  * @sw: console driver
3820  *
3821  * Called when the console is taken over by the kernel debugger, this
3822  * function needs to save the current console state, then put the console
3823  * into a state suitable for the kernel debugger.
3824  *
3825  * RETURNS:
3826  * Zero on success, nonzero if a failure occurred when trying to prepare
3827  * the console for the debugger.
3828  */
3829 int con_debug_enter(struct vc_data *vc)
3830 {
3831         int ret = 0;
3832
3833         saved_fg_console = fg_console;
3834         saved_last_console = last_console;
3835         saved_want_console = want_console;
3836         saved_vc_mode = vc->vc_mode;
3837         saved_console_blanked = console_blanked;
3838         vc->vc_mode = KD_TEXT;
3839         console_blanked = 0;
3840         if (vc->vc_sw->con_debug_enter)
3841                 ret = vc->vc_sw->con_debug_enter(vc);
3842 #ifdef CONFIG_KGDB_KDB
3843         /* Set the initial LINES variable if it is not already set */
3844         if (vc->vc_rows < 999) {
3845                 int linecount;
3846                 char lns[4];
3847                 const char *setargs[3] = {
3848                         "set",
3849                         "LINES",
3850                         lns,
3851                 };
3852                 if (kdbgetintenv(setargs[0], &linecount)) {
3853                         snprintf(lns, 4, "%i", vc->vc_rows);
3854                         kdb_set(2, setargs);
3855                 }
3856         }
3857         if (vc->vc_cols < 999) {
3858                 int colcount;
3859                 char cols[4];
3860                 const char *setargs[3] = {
3861                         "set",
3862                         "COLUMNS",
3863                         cols,
3864                 };
3865                 if (kdbgetintenv(setargs[0], &colcount)) {
3866                         snprintf(cols, 4, "%i", vc->vc_cols);
3867                         kdb_set(2, setargs);
3868                 }
3869         }
3870 #endif /* CONFIG_KGDB_KDB */
3871         return ret;
3872 }
3873 EXPORT_SYMBOL_GPL(con_debug_enter);
3874
3875 /**
3876  * con_debug_leave - restore console state
3877  * @sw: console driver
3878  *
3879  * Restore the console state to what it was before the kernel debugger
3880  * was invoked.
3881  *
3882  * RETURNS:
3883  * Zero on success, nonzero if a failure occurred when trying to restore
3884  * the console.
3885  */
3886 int con_debug_leave(void)
3887 {
3888         struct vc_data *vc;
3889         int ret = 0;
3890
3891         fg_console = saved_fg_console;
3892         last_console = saved_last_console;
3893         want_console = saved_want_console;
3894         console_blanked = saved_console_blanked;
3895         vc_cons[fg_console].d->vc_mode = saved_vc_mode;
3896
3897         vc = vc_cons[fg_console].d;
3898         if (vc->vc_sw->con_debug_leave)
3899                 ret = vc->vc_sw->con_debug_leave(vc);
3900         return ret;
3901 }
3902 EXPORT_SYMBOL_GPL(con_debug_leave);
3903
3904 static int do_register_con_driver(const struct consw *csw, int first, int last)
3905 {
3906         struct module *owner = csw->owner;
3907         struct con_driver *con_driver;
3908         const char *desc;
3909         int i, retval;
3910
3911         WARN_CONSOLE_UNLOCKED();
3912
3913         if (!try_module_get(owner))
3914                 return -ENODEV;
3915
3916         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3917                 con_driver = &registered_con_driver[i];
3918
3919                 /* already registered */
3920                 if (con_driver->con == csw) {
3921                         retval = -EBUSY;
3922                         goto err;
3923                 }
3924         }
3925
3926         desc = csw->con_startup();
3927         if (!desc) {
3928                 retval = -ENODEV;
3929                 goto err;
3930         }
3931
3932         retval = -EINVAL;
3933
3934         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3935                 con_driver = &registered_con_driver[i];
3936
3937                 if (con_driver->con == NULL &&
3938                     !(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE)) {
3939                         con_driver->con = csw;
3940                         con_driver->desc = desc;
3941                         con_driver->node = i;
3942                         con_driver->flag = CON_DRIVER_FLAG_MODULE |
3943                                            CON_DRIVER_FLAG_INIT;
3944                         con_driver->first = first;
3945                         con_driver->last = last;
3946                         retval = 0;
3947                         break;
3948                 }
3949         }
3950
3951         if (retval)
3952                 goto err;
3953
3954         con_driver->dev =
3955                 device_create_with_groups(vtconsole_class, NULL,
3956                                           MKDEV(0, con_driver->node),
3957                                           con_driver, con_dev_groups,
3958                                           "vtcon%i", con_driver->node);
3959         if (IS_ERR(con_driver->dev)) {
3960                 pr_warn("Unable to create device for %s; errno = %ld\n",
3961                         con_driver->desc, PTR_ERR(con_driver->dev));
3962                 con_driver->dev = NULL;
3963         } else {
3964                 vtconsole_init_device(con_driver);
3965         }
3966
3967 err:
3968         module_put(owner);
3969         return retval;
3970 }
3971
3972
3973 /**
3974  * do_unregister_con_driver - unregister console driver from console layer
3975  * @csw: console driver
3976  *
3977  * DESCRIPTION: All drivers that registers to the console layer must
3978  * call this function upon exit, or if the console driver is in a state
3979  * where it won't be able to handle console services, such as the
3980  * framebuffer console without loaded framebuffer drivers.
3981  *
3982  * The driver must unbind first prior to unregistration.
3983  */
3984 int do_unregister_con_driver(const struct consw *csw)
3985 {
3986         int i;
3987
3988         /* cannot unregister a bound driver */
3989         if (con_is_bound(csw))
3990                 return -EBUSY;
3991
3992         if (csw == conswitchp)
3993                 return -EINVAL;
3994
3995         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3996                 struct con_driver *con_driver = &registered_con_driver[i];
3997
3998                 if (con_driver->con == csw) {
3999                         /*
4000                          * Defer the removal of the sysfs entries since that
4001                          * will acquire the kernfs s_active lock and we can't
4002                          * acquire this lock while holding the console lock:
4003                          * the unbind sysfs entry imposes already the opposite
4004                          * order. Reset con already here to prevent any later
4005                          * lookup to succeed and mark this slot as zombie, so
4006                          * it won't get reused until we complete the removal
4007                          * in the deferred work.
4008                          */
4009                         con_driver->con = NULL;
4010                         con_driver->flag = CON_DRIVER_FLAG_ZOMBIE;
4011                         schedule_work(&con_driver_unregister_work);
4012
4013                         return 0;
4014                 }
4015         }
4016
4017         return -ENODEV;
4018 }
4019 EXPORT_SYMBOL_GPL(do_unregister_con_driver);
4020
4021 static void con_driver_unregister_callback(struct work_struct *ignored)
4022 {
4023         int i;
4024
4025         console_lock();
4026
4027         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4028                 struct con_driver *con_driver = &registered_con_driver[i];
4029
4030                 if (!(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE))
4031                         continue;
4032
4033                 console_unlock();
4034
4035                 vtconsole_deinit_device(con_driver);
4036                 device_destroy(vtconsole_class, MKDEV(0, con_driver->node));
4037
4038                 console_lock();
4039
4040                 if (WARN_ON_ONCE(con_driver->con))
4041                         con_driver->con = NULL;
4042                 con_driver->desc = NULL;
4043                 con_driver->dev = NULL;
4044                 con_driver->node = 0;
4045                 WARN_ON_ONCE(con_driver->flag != CON_DRIVER_FLAG_ZOMBIE);
4046                 con_driver->flag = 0;
4047                 con_driver->first = 0;
4048                 con_driver->last = 0;
4049         }
4050
4051         console_unlock();
4052 }
4053
4054 /*
4055  *      If we support more console drivers, this function is used
4056  *      when a driver wants to take over some existing consoles
4057  *      and become default driver for newly opened ones.
4058  *
4059  *      do_take_over_console is basically a register followed by unbind
4060  */
4061 int do_take_over_console(const struct consw *csw, int first, int last, int deflt)
4062 {
4063         int err;
4064
4065         err = do_register_con_driver(csw, first, last);
4066         /*
4067          * If we get an busy error we still want to bind the console driver
4068          * and return success, as we may have unbound the console driver
4069          * but not unregistered it.
4070          */
4071         if (err == -EBUSY)
4072                 err = 0;
4073         if (!err)
4074                 do_bind_con_driver(csw, first, last, deflt);
4075
4076         return err;
4077 }
4078 EXPORT_SYMBOL_GPL(do_take_over_console);
4079
4080
4081 /*
4082  * give_up_console is a wrapper to unregister_con_driver. It will only
4083  * work if driver is fully unbound.
4084  */
4085 void give_up_console(const struct consw *csw)
4086 {
4087         console_lock();
4088         do_unregister_con_driver(csw);
4089         console_unlock();
4090 }
4091
4092 static int __init vtconsole_class_init(void)
4093 {
4094         int i;
4095
4096         vtconsole_class = class_create(THIS_MODULE, "vtconsole");
4097         if (IS_ERR(vtconsole_class)) {
4098                 pr_warn("Unable to create vt console class; errno = %ld\n",
4099                         PTR_ERR(vtconsole_class));
4100                 vtconsole_class = NULL;
4101         }
4102
4103         /* Add system drivers to sysfs */
4104         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4105                 struct con_driver *con = &registered_con_driver[i];
4106
4107                 if (con->con && !con->dev) {
4108                         con->dev =
4109                                 device_create_with_groups(vtconsole_class, NULL,
4110                                                           MKDEV(0, con->node),
4111                                                           con, con_dev_groups,
4112                                                           "vtcon%i", con->node);
4113
4114                         if (IS_ERR(con->dev)) {
4115                                 pr_warn("Unable to create device for %s; errno = %ld\n",
4116                                         con->desc, PTR_ERR(con->dev));
4117                                 con->dev = NULL;
4118                         } else {
4119                                 vtconsole_init_device(con);
4120                         }
4121                 }
4122         }
4123
4124         return 0;
4125 }
4126 postcore_initcall(vtconsole_class_init);
4127
4128 #endif
4129
4130 /*
4131  *      Screen blanking
4132  */
4133
4134 static int set_vesa_blanking(char __user *p)
4135 {
4136         unsigned int mode;
4137
4138         if (get_user(mode, p + 1))
4139                 return -EFAULT;
4140
4141         vesa_blank_mode = (mode < 4) ? mode : 0;
4142         return 0;
4143 }
4144
4145 void do_blank_screen(int entering_gfx)
4146 {
4147         struct vc_data *vc = vc_cons[fg_console].d;
4148         int i;
4149
4150         WARN_CONSOLE_UNLOCKED();
4151
4152         if (console_blanked) {
4153                 if (blank_state == blank_vesa_wait) {
4154                         blank_state = blank_off;
4155                         vc->vc_sw->con_blank(vc, vesa_blank_mode + 1, 0);
4156                 }
4157                 return;
4158         }
4159
4160         /* entering graphics mode? */
4161         if (entering_gfx) {
4162                 hide_cursor(vc);
4163                 save_screen(vc);
4164                 vc->vc_sw->con_blank(vc, -1, 1);
4165                 console_blanked = fg_console + 1;
4166                 blank_state = blank_off;
4167                 set_origin(vc);
4168                 return;
4169         }
4170
4171         if (blank_state != blank_normal_wait)
4172                 return;
4173         blank_state = blank_off;
4174
4175         /* don't blank graphics */
4176         if (vc->vc_mode != KD_TEXT) {
4177                 console_blanked = fg_console + 1;
4178                 return;
4179         }
4180
4181         hide_cursor(vc);
4182         del_timer_sync(&console_timer);
4183         blank_timer_expired = 0;
4184
4185         save_screen(vc);
4186         /* In case we need to reset origin, blanking hook returns 1 */
4187         i = vc->vc_sw->con_blank(vc, vesa_off_interval ? 1 : (vesa_blank_mode + 1), 0);
4188         console_blanked = fg_console + 1;
4189         if (i)
4190                 set_origin(vc);
4191
4192         if (console_blank_hook && console_blank_hook(1))
4193                 return;
4194
4195         if (vesa_off_interval && vesa_blank_mode) {
4196                 blank_state = blank_vesa_wait;
4197                 mod_timer(&console_timer, jiffies + vesa_off_interval);
4198         }
4199         vt_event_post(VT_EVENT_BLANK, vc->vc_num, vc->vc_num);
4200 }
4201 EXPORT_SYMBOL(do_blank_screen);
4202
4203 /*
4204  * Called by timer as well as from vt_console_driver
4205  */
4206 void do_unblank_screen(int leaving_gfx)
4207 {
4208         struct vc_data *vc;
4209
4210         /* This should now always be called from a "sane" (read: can schedule)
4211          * context for the sake of the low level drivers, except in the special
4212          * case of oops_in_progress
4213          */
4214         if (!oops_in_progress)
4215                 might_sleep();
4216
4217         WARN_CONSOLE_UNLOCKED();
4218
4219         ignore_poke = 0;
4220         if (!console_blanked)
4221                 return;
4222         if (!vc_cons_allocated(fg_console)) {
4223                 /* impossible */
4224                 pr_warn("unblank_screen: tty %d not allocated ??\n",
4225                         fg_console + 1);
4226                 return;
4227         }
4228         vc = vc_cons[fg_console].d;
4229         if (vc->vc_mode != KD_TEXT)
4230                 return; /* but leave console_blanked != 0 */
4231
4232         if (blankinterval) {
4233                 mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4234                 blank_state = blank_normal_wait;
4235         }
4236
4237         console_blanked = 0;
4238         if (vc->vc_sw->con_blank(vc, 0, leaving_gfx))
4239                 /* Low-level driver cannot restore -> do it ourselves */
4240                 update_screen(vc);
4241         if (console_blank_hook)
4242                 console_blank_hook(0);
4243         set_palette(vc);
4244         set_cursor(vc);
4245         vt_event_post(VT_EVENT_UNBLANK, vc->vc_num, vc->vc_num);
4246 }
4247 EXPORT_SYMBOL(do_unblank_screen);
4248
4249 /*
4250  * This is called by the outside world to cause a forced unblank, mostly for
4251  * oopses. Currently, I just call do_unblank_screen(0), but we could eventually
4252  * call it with 1 as an argument and so force a mode restore... that may kill
4253  * X or at least garbage the screen but would also make the Oops visible...
4254  */
4255 void unblank_screen(void)
4256 {
4257         do_unblank_screen(0);
4258 }
4259
4260 /*
4261  * We defer the timer blanking to work queue so it can take the console mutex
4262  * (console operations can still happen at irq time, but only from printk which
4263  * has the console mutex. Not perfect yet, but better than no locking
4264  */
4265 static void blank_screen_t(struct timer_list *unused)
4266 {
4267         blank_timer_expired = 1;
4268         schedule_work(&console_work);
4269 }
4270
4271 void poke_blanked_console(void)
4272 {
4273         WARN_CONSOLE_UNLOCKED();
4274
4275         /* Add this so we quickly catch whoever might call us in a non
4276          * safe context. Nowadays, unblank_screen() isn't to be called in
4277          * atomic contexts and is allowed to schedule (with the special case
4278          * of oops_in_progress, but that isn't of any concern for this
4279          * function. --BenH.
4280          */
4281         might_sleep();
4282
4283         /* This isn't perfectly race free, but a race here would be mostly harmless,
4284          * at worse, we'll do a spurrious blank and it's unlikely
4285          */
4286         del_timer(&console_timer);
4287         blank_timer_expired = 0;
4288
4289         if (ignore_poke || !vc_cons[fg_console].d || vc_cons[fg_console].d->vc_mode == KD_GRAPHICS)
4290                 return;
4291         if (console_blanked)
4292                 unblank_screen();
4293         else if (blankinterval) {
4294                 mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4295                 blank_state = blank_normal_wait;
4296         }
4297 }
4298
4299 /*
4300  *      Palettes
4301  */
4302
4303 static void set_palette(struct vc_data *vc)
4304 {
4305         WARN_CONSOLE_UNLOCKED();
4306
4307         if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_set_palette)
4308                 vc->vc_sw->con_set_palette(vc, color_table);
4309 }
4310
4311 /*
4312  * Load palette into the DAC registers. arg points to a colour
4313  * map, 3 bytes per colour, 16 colours, range from 0 to 255.
4314  */
4315
4316 int con_set_cmap(unsigned char __user *arg)
4317 {
4318         int i, j, k;
4319         unsigned char colormap[3*16];
4320
4321         if (copy_from_user(colormap, arg, sizeof(colormap)))
4322                 return -EFAULT;
4323
4324         console_lock();
4325         for (i = k = 0; i < 16; i++) {
4326                 default_red[i] = colormap[k++];
4327                 default_grn[i] = colormap[k++];
4328                 default_blu[i] = colormap[k++];
4329         }
4330         for (i = 0; i < MAX_NR_CONSOLES; i++) {
4331                 if (!vc_cons_allocated(i))
4332                         continue;
4333                 for (j = k = 0; j < 16; j++) {
4334                         vc_cons[i].d->vc_palette[k++] = default_red[j];
4335                         vc_cons[i].d->vc_palette[k++] = default_grn[j];
4336                         vc_cons[i].d->vc_palette[k++] = default_blu[j];
4337                 }
4338                 set_palette(vc_cons[i].d);
4339         }
4340         console_unlock();
4341
4342         return 0;
4343 }
4344
4345 int con_get_cmap(unsigned char __user *arg)
4346 {
4347         int i, k;
4348         unsigned char colormap[3*16];
4349
4350         console_lock();
4351         for (i = k = 0; i < 16; i++) {
4352                 colormap[k++] = default_red[i];
4353                 colormap[k++] = default_grn[i];
4354                 colormap[k++] = default_blu[i];
4355         }
4356         console_unlock();
4357
4358         if (copy_to_user(arg, colormap, sizeof(colormap)))
4359                 return -EFAULT;
4360
4361         return 0;
4362 }
4363
4364 void reset_palette(struct vc_data *vc)
4365 {
4366         int j, k;
4367         for (j=k=0; j<16; j++) {
4368                 vc->vc_palette[k++] = default_red[j];
4369                 vc->vc_palette[k++] = default_grn[j];
4370                 vc->vc_palette[k++] = default_blu[j];
4371         }
4372         set_palette(vc);
4373 }
4374
4375 /*
4376  *  Font switching
4377  *
4378  *  Currently we only support fonts up to 32 pixels wide, at a maximum height
4379  *  of 32 pixels. Userspace fontdata is stored with 32 bytes (shorts/ints,
4380  *  depending on width) reserved for each character which is kinda wasty, but
4381  *  this is done in order to maintain compatibility with the EGA/VGA fonts. It
4382  *  is up to the actual low-level console-driver convert data into its favorite
4383  *  format (maybe we should add a `fontoffset' field to the `display'
4384  *  structure so we won't have to convert the fontdata all the time.
4385  *  /Jes
4386  */
4387
4388 #define max_font_size 65536
4389
4390 static int con_font_get(struct vc_data *vc, struct console_font_op *op)
4391 {
4392         struct console_font font;
4393         int rc = -EINVAL;
4394         int c;
4395
4396         if (op->data) {
4397                 font.data = kmalloc(max_font_size, GFP_KERNEL);
4398                 if (!font.data)
4399                         return -ENOMEM;
4400         } else
4401                 font.data = NULL;
4402
4403         console_lock();
4404         if (vc->vc_mode != KD_TEXT)
4405                 rc = -EINVAL;
4406         else if (vc->vc_sw->con_font_get)
4407                 rc = vc->vc_sw->con_font_get(vc, &font);
4408         else
4409                 rc = -ENOSYS;
4410         console_unlock();
4411
4412         if (rc)
4413                 goto out;
4414
4415         c = (font.width+7)/8 * 32 * font.charcount;
4416
4417         if (op->data && font.charcount > op->charcount)
4418                 rc = -ENOSPC;
4419         if (!(op->flags & KD_FONT_FLAG_OLD)) {
4420                 if (font.width > op->width || font.height > op->height)
4421                         rc = -ENOSPC;
4422         } else {
4423                 if (font.width != 8)
4424                         rc = -EIO;
4425                 else if ((op->height && font.height > op->height) ||
4426                          font.height > 32)
4427                         rc = -ENOSPC;
4428         }
4429         if (rc)
4430                 goto out;
4431
4432         op->height = font.height;
4433         op->width = font.width;
4434         op->charcount = font.charcount;
4435
4436         if (op->data && copy_to_user(op->data, font.data, c))
4437                 rc = -EFAULT;
4438
4439 out:
4440         kfree(font.data);
4441         return rc;
4442 }
4443
4444 static int con_font_set(struct vc_data *vc, struct console_font_op *op)
4445 {
4446         struct console_font font;
4447         int rc = -EINVAL;
4448         int size;
4449
4450         if (vc->vc_mode != KD_TEXT)
4451                 return -EINVAL;
4452         if (!op->data)
4453                 return -EINVAL;
4454         if (op->charcount > 512)
4455                 return -EINVAL;
4456         if (op->width <= 0 || op->width > 32 || op->height > 32)
4457                 return -EINVAL;
4458         size = (op->width+7)/8 * 32 * op->charcount;
4459         if (size > max_font_size)
4460                 return -ENOSPC;
4461
4462         font.data = memdup_user(op->data, size);
4463         if (IS_ERR(font.data))
4464                 return PTR_ERR(font.data);
4465
4466         if (!op->height) {              /* Need to guess font height [compat] */
4467                 int h, i;
4468                 u8 *charmap = font.data;
4469
4470                 /*
4471                  * If from KDFONTOP ioctl, don't allow things which can be done
4472                  * in userland,so that we can get rid of this soon
4473                  */
4474                 if (!(op->flags & KD_FONT_FLAG_OLD)) {
4475                         kfree(font.data);
4476                         return -EINVAL;
4477                 }
4478
4479                 for (h = 32; h > 0; h--)
4480                         for (i = 0; i < op->charcount; i++)
4481                                 if (charmap[32*i+h-1])
4482                                         goto nonzero;
4483
4484                 kfree(font.data);
4485                 return -EINVAL;
4486
4487         nonzero:
4488                 op->height = h;
4489         }
4490
4491         font.charcount = op->charcount;
4492         font.width = op->width;
4493         font.height = op->height;
4494
4495         console_lock();
4496         if (vc->vc_mode != KD_TEXT)
4497                 rc = -EINVAL;
4498         else if (vc->vc_sw->con_font_set)
4499                 rc = vc->vc_sw->con_font_set(vc, &font, op->flags);
4500         else
4501                 rc = -ENOSYS;
4502         console_unlock();
4503         kfree(font.data);
4504         return rc;
4505 }
4506
4507 static int con_font_default(struct vc_data *vc, struct console_font_op *op)
4508 {
4509         struct console_font font = {.width = op->width, .height = op->height};
4510         char name[MAX_FONT_NAME];
4511         char *s = name;
4512         int rc;
4513
4514
4515         if (!op->data)
4516                 s = NULL;
4517         else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0)
4518                 return -EFAULT;
4519         else
4520                 name[MAX_FONT_NAME - 1] = 0;
4521
4522         console_lock();
4523         if (vc->vc_mode != KD_TEXT) {
4524                 console_unlock();
4525                 return -EINVAL;
4526         }
4527         if (vc->vc_sw->con_font_default)
4528                 rc = vc->vc_sw->con_font_default(vc, &font, s);
4529         else
4530                 rc = -ENOSYS;
4531         console_unlock();
4532         if (!rc) {
4533                 op->width = font.width;
4534                 op->height = font.height;
4535         }
4536         return rc;
4537 }
4538
4539 static int con_font_copy(struct vc_data *vc, struct console_font_op *op)
4540 {
4541         int con = op->height;
4542         int rc;
4543
4544
4545         console_lock();
4546         if (vc->vc_mode != KD_TEXT)
4547                 rc = -EINVAL;
4548         else if (!vc->vc_sw->con_font_copy)
4549                 rc = -ENOSYS;
4550         else if (con < 0 || !vc_cons_allocated(con))
4551                 rc = -ENOTTY;
4552         else if (con == vc->vc_num)     /* nothing to do */
4553                 rc = 0;
4554         else
4555                 rc = vc->vc_sw->con_font_copy(vc, con);
4556         console_unlock();
4557         return rc;
4558 }
4559
4560 int con_font_op(struct vc_data *vc, struct console_font_op *op)
4561 {
4562         switch (op->op) {
4563         case KD_FONT_OP_SET:
4564                 return con_font_set(vc, op);
4565         case KD_FONT_OP_GET:
4566                 return con_font_get(vc, op);
4567         case KD_FONT_OP_SET_DEFAULT:
4568                 return con_font_default(vc, op);
4569         case KD_FONT_OP_COPY:
4570                 return con_font_copy(vc, op);
4571         }
4572         return -ENOSYS;
4573 }
4574
4575 /*
4576  *      Interface exported to selection and vcs.
4577  */
4578
4579 /* used by selection */
4580 u16 screen_glyph(struct vc_data *vc, int offset)
4581 {
4582         u16 w = scr_readw(screenpos(vc, offset, 1));
4583         u16 c = w & 0xff;
4584
4585         if (w & vc->vc_hi_font_mask)
4586                 c |= 0x100;
4587         return c;
4588 }
4589 EXPORT_SYMBOL_GPL(screen_glyph);
4590
4591 u32 screen_glyph_unicode(struct vc_data *vc, int n)
4592 {
4593         struct uni_screen *uniscr = get_vc_uniscr(vc);
4594
4595         if (uniscr)
4596                 return uniscr->lines[n / vc->vc_cols][n % vc->vc_cols];
4597         return inverse_translate(vc, screen_glyph(vc, n * 2), 1);
4598 }
4599 EXPORT_SYMBOL_GPL(screen_glyph_unicode);
4600
4601 /* used by vcs - note the word offset */
4602 unsigned short *screen_pos(struct vc_data *vc, int w_offset, int viewed)
4603 {
4604         return screenpos(vc, 2 * w_offset, viewed);
4605 }
4606 EXPORT_SYMBOL_GPL(screen_pos);
4607
4608 void getconsxy(struct vc_data *vc, unsigned char *p)
4609 {
4610         p[0] = vc->vc_x;
4611         p[1] = vc->vc_y;
4612 }
4613
4614 void putconsxy(struct vc_data *vc, unsigned char *p)
4615 {
4616         hide_cursor(vc);
4617         gotoxy(vc, p[0], p[1]);
4618         set_cursor(vc);
4619 }
4620
4621 u16 vcs_scr_readw(struct vc_data *vc, const u16 *org)
4622 {
4623         if ((unsigned long)org == vc->vc_pos && softcursor_original != -1)
4624                 return softcursor_original;
4625         return scr_readw(org);
4626 }
4627
4628 void vcs_scr_writew(struct vc_data *vc, u16 val, u16 *org)
4629 {
4630         scr_writew(val, org);
4631         if ((unsigned long)org == vc->vc_pos) {
4632                 softcursor_original = -1;
4633                 add_softcursor(vc);
4634         }
4635 }
4636
4637 void vcs_scr_updated(struct vc_data *vc)
4638 {
4639         notify_update(vc);
4640 }
4641
4642 void vc_scrolldelta_helper(struct vc_data *c, int lines,
4643                 unsigned int rolled_over, void *base, unsigned int size)
4644 {
4645         unsigned long ubase = (unsigned long)base;
4646         ptrdiff_t scr_end = (void *)c->vc_scr_end - base;
4647         ptrdiff_t vorigin = (void *)c->vc_visible_origin - base;
4648         ptrdiff_t origin = (void *)c->vc_origin - base;
4649         int margin = c->vc_size_row * 4;
4650         int from, wrap, from_off, avail;
4651
4652         /* Turn scrollback off */
4653         if (!lines) {
4654                 c->vc_visible_origin = c->vc_origin;
4655                 return;
4656         }
4657
4658         /* Do we have already enough to allow jumping from 0 to the end? */
4659         if (rolled_over > scr_end + margin) {
4660                 from = scr_end;
4661                 wrap = rolled_over + c->vc_size_row;
4662         } else {
4663                 from = 0;
4664                 wrap = size;
4665         }
4666
4667         from_off = (vorigin - from + wrap) % wrap + lines * c->vc_size_row;
4668         avail = (origin - from + wrap) % wrap;
4669
4670         /* Only a little piece would be left? Show all incl. the piece! */
4671         if (avail < 2 * margin)
4672                 margin = 0;
4673         if (from_off < margin)
4674                 from_off = 0;
4675         if (from_off > avail - margin)
4676                 from_off = avail;
4677
4678         c->vc_visible_origin = ubase + (from + from_off) % wrap;
4679 }
4680 EXPORT_SYMBOL_GPL(vc_scrolldelta_helper);
4681
4682 /*
4683  *      Visible symbols for modules
4684  */
4685
4686 EXPORT_SYMBOL(color_table);
4687 EXPORT_SYMBOL(default_red);
4688 EXPORT_SYMBOL(default_grn);
4689 EXPORT_SYMBOL(default_blu);
4690 EXPORT_SYMBOL(update_region);
4691 EXPORT_SYMBOL(redraw_screen);
4692 EXPORT_SYMBOL(vc_resize);
4693 EXPORT_SYMBOL(fg_console);
4694 EXPORT_SYMBOL(console_blank_hook);
4695 EXPORT_SYMBOL(console_blanked);
4696 EXPORT_SYMBOL(vc_cons);
4697 EXPORT_SYMBOL(global_cursor_default);
4698 #ifndef VT_SINGLE_DRIVER
4699 EXPORT_SYMBOL(give_up_console);
4700 #endif