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/vmalloc.h>
  85 #include <linux/major.h>
  86 #include <linux/mm.h>
  87 #include <linux/console.h>
  88 #include <linux/init.h>
  89 #include <linux/mutex.h>
  90 #include <linux/vt_kern.h>
  91 #include <linux/selection.h>
  92 #include <linux/tiocl.h>
  93 #include <linux/kbd_kern.h>
  94 #include <linux/consolemap.h>
  95 #include <linux/timer.h>
  96 #include <linux/interrupt.h>
  97 #include <linux/workqueue.h>
  98 #include <linux/pm.h>
  99 #include <linux/font.h>
 100 #include <linux/bitops.h>
 101 #include <linux/notifier.h>
 102 #include <linux/device.h>
 103 #include <linux/io.h>
 104 #include <linux/uaccess.h>
 105 #include <linux/kdb.h>
 106 #include <linux/ctype.h>
 107 #include <linux/bsearch.h>
 108 #include <linux/gcd.h>
 109
 110 #define MAX_NR_CON_DRIVER 16
 111
 112 #define CON_DRIVER_FLAG_MODULE 1
 113 #define CON_DRIVER_FLAG_INIT   2
 114 #define CON_DRIVER_FLAG_ATTR   4
 115 #define CON_DRIVER_FLAG_ZOMBIE 8
 116
 117 struct con_driver {
 118         const struct consw *con;
 119         const char *desc;
 120         struct device *dev;
 121         int node;
 122         int first;
 123         int last;
 124         int flag;
 125 };
 126
 127 static struct con_driver registered_con_driver[MAX_NR_CON_DRIVER];
 128 const struct consw *conswitchp;
 129
 130 /*
 131  * Here is the default bell parameters: 750HZ, 1/8th of a second
 132  */
 133 #define DEFAULT_BELL_PITCH      750
 134 #define DEFAULT_BELL_DURATION   (HZ/8)
 135 #define DEFAULT_CURSOR_BLINK_MS 200
 136
 137 struct vc vc_cons [MAX_NR_CONSOLES];
 138
 139 #ifndef VT_SINGLE_DRIVER
 140 static const struct consw *con_driver_map[MAX_NR_CONSOLES];
 141 #endif
 142
 143 static int con_open(struct tty_struct *, struct file *);
 144 static void vc_init(struct vc_data *vc, unsigned int rows,
 145                     unsigned int cols, int do_clear);
 146 static void gotoxy(struct vc_data *vc, int new_x, int new_y);
 147 static void save_cur(struct vc_data *vc);
 148 static void reset_terminal(struct vc_data *vc, int do_clear);
 149 static void con_flush_chars(struct tty_struct *tty);
 150 static int set_vesa_blanking(char __user *p);
 151 static void set_cursor(struct vc_data *vc);
 152 static void hide_cursor(struct vc_data *vc);
 153 static void console_callback(struct work_struct *ignored);
 154 static void con_driver_unregister_callback(struct work_struct *ignored);
 155 static void blank_screen_t(struct timer_list *unused);
 156 static void set_palette(struct vc_data *vc);
 157
 158 #define vt_get_kmsg_redirect() vt_kmsg_redirect(-1)
 159
 160 static int printable;           /* Is console ready for printing? */
 161 int default_utf8 = true;
 162 module_param(default_utf8, int, S_IRUGO | S_IWUSR);
 163 int global_cursor_default = -1;
 164 module_param(global_cursor_default, int, S_IRUGO | S_IWUSR);
 165
 166 static int cur_default = CUR_UNDERLINE;
 167 module_param(cur_default, int, S_IRUGO | S_IWUSR);
 168
 169 /*
 170  * ignore_poke: don't unblank the screen when things are typed.  This is
 171  * mainly for the privacy of braille terminal users.
 172  */
 173 static int ignore_poke;
 174
 175 int do_poke_blanked_console;
 176 int console_blanked;
 177
 178 static int vesa_blank_mode; /* 0:none 1:suspendV 2:suspendH 3:powerdown */
 179 static int vesa_off_interval;
 180 static int blankinterval;
 181 core_param(consoleblank, blankinterval, int, 0444);
 182
 183 static DECLARE_WORK(console_work, console_callback);
 184 static DECLARE_WORK(con_driver_unregister_work, con_driver_unregister_callback);
 185
 186 /*
 187  * fg_console is the current virtual console,
 188  * last_console is the last used one,
 189  * want_console is the console we want to switch to,
 190  * saved_* variants are for save/restore around kernel debugger enter/leave
 191  */
 192 int fg_console;
 193 int last_console;
 194 int want_console = -1;
 195 static int saved_fg_console;
 196 static int saved_last_console;
 197 static int saved_want_console;
 198 static int saved_vc_mode;
 199 static int saved_console_blanked;
 200
 201 /*
 202  * For each existing display, we have a pointer to console currently visible
 203  * on that display, allowing consoles other than fg_console to be refreshed
 204  * appropriately. Unless the low-level driver supplies its own display_fg
 205  * variable, we use this one for the "master display".
 206  */
 207 static struct vc_data *master_display_fg;
 208
 209 /*
 210  * Unfortunately, we need to delay tty echo when we're currently writing to the
 211  * console since the code is (and always was) not re-entrant, so we schedule
 212  * all flip requests to process context with schedule-task() and run it from
 213  * console_callback().
 214  */
 215
 216 /*
 217  * For the same reason, we defer scrollback to the console callback.
 218  */
 219 static int scrollback_delta;
 220
 221 /*
 222  * Hook so that the power management routines can (un)blank
 223  * the console on our behalf.
 224  */
 225 int (*console_blank_hook)(int);
 226
 227 static DEFINE_TIMER(console_timer, blank_screen_t);
 228 static int blank_state;
 229 static int blank_timer_expired;
 230 enum {
 231         blank_off = 0,
 232         blank_normal_wait,
 233         blank_vesa_wait,
 234 };
 235
 236 /*
 237  * /sys/class/tty/tty0/
 238  *
 239  * the attribute 'active' contains the name of the current vc
 240  * console and it supports poll() to detect vc switches
 241  */
 242 static struct device *tty0dev;
 243
 244 /*
 245  * Notifier list for console events.
 246  */
 247 static ATOMIC_NOTIFIER_HEAD(vt_notifier_list);
 248
 249 int register_vt_notifier(struct notifier_block *nb)
 250 {
 251         return atomic_notifier_chain_register(&vt_notifier_list, nb);
 252 }
 253 EXPORT_SYMBOL_GPL(register_vt_notifier);
 254
 255 int unregister_vt_notifier(struct notifier_block *nb)
 256 {
 257         return atomic_notifier_chain_unregister(&vt_notifier_list, nb);
 258 }
 259 EXPORT_SYMBOL_GPL(unregister_vt_notifier);
 260
 261 static void notify_write(struct vc_data *vc, unsigned int unicode)
 262 {
 263         struct vt_notifier_param param = { .vc = vc, .c = unicode };
 264         atomic_notifier_call_chain(&vt_notifier_list, VT_WRITE, &param);
 265 }
 266
 267 static void notify_update(struct vc_data *vc)
 268 {
 269         struct vt_notifier_param param = { .vc = vc };
 270         atomic_notifier_call_chain(&vt_notifier_list, VT_UPDATE, &param);
 271 }
 272 /*
 273  *      Low-Level Functions
 274  */
 275
 276 static inline bool con_is_fg(const struct vc_data *vc)
 277 {
 278         return vc->vc_num == fg_console;
 279 }
 280
 281 static inline bool con_should_update(const struct vc_data *vc)
 282 {
 283         return con_is_visible(vc) && !console_blanked;
 284 }
 285
 286 static inline unsigned short *screenpos(struct vc_data *vc, int offset, int viewed)
 287 {
 288         unsigned short *p;
 289
 290         if (!viewed)
 291                 p = (unsigned short *)(vc->vc_origin + offset);
 292         else if (!vc->vc_sw->con_screen_pos)
 293                 p = (unsigned short *)(vc->vc_visible_origin + offset);
 294         else
 295                 p = vc->vc_sw->con_screen_pos(vc, offset);
 296         return p;
 297 }
 298
 299 /* Called  from the keyboard irq path.. */
 300 static inline void scrolldelta(int lines)
 301 {
 302         /* FIXME */
 303         /* scrolldelta needs some kind of consistency lock, but the BKL was
 304            and still is not protecting versus the scheduled back end */
 305         scrollback_delta += lines;
 306         schedule_console_callback();
 307 }
 308
 309 void schedule_console_callback(void)
 310 {
 311         schedule_work(&console_work);
 312 }
 313
 314 /*
 315  * Code to manage unicode-based screen buffers
 316  */
 317
 318 #ifdef NO_VC_UNI_SCREEN
 319 /* this disables and optimizes related code away at compile time */
 320 #define get_vc_uniscr(vc) NULL
 321 #else
 322 #define get_vc_uniscr(vc) vc->vc_uni_screen
 323 #endif
 324
 325 #define VC_UNI_SCREEN_DEBUG 0
 326
 327 typedef uint32_t char32_t;
 328
 329 /*
 330  * Our screen buffer is preceded by an array of line pointers so that
 331  * scrolling only implies some pointer shuffling.
 332  */
 333 struct uni_screen {
 334         char32_t *lines[0];
 335 };
 336
 337 static struct uni_screen *vc_uniscr_alloc(unsigned int cols, unsigned int rows)
 338 {
 339         struct uni_screen *uniscr;
 340         void *p;
 341         unsigned int memsize, i;
 342
 343         /* allocate everything in one go */
 344         memsize = cols * rows * sizeof(char32_t);
 345         memsize += rows * sizeof(char32_t *);
 346         p = vmalloc(memsize);
 347         if (!p)
 348                 return NULL;
 349
 350         /* initial line pointers */
 351         uniscr = p;
 352         p = uniscr->lines + rows;
 353         for (i = 0; i < rows; i++) {
 354                 uniscr->lines[i] = p;
 355                 p += cols * sizeof(char32_t);
 356         }
 357         return uniscr;
 358 }
 359
 360 static void vc_uniscr_free(struct uni_screen *uniscr)
 361 {
 362         vfree(uniscr);
 363 }
 364
 365 static void vc_uniscr_set(struct vc_data *vc, struct uni_screen *new_uniscr)
 366 {
 367         vc_uniscr_free(vc->vc_uni_screen);
 368         vc->vc_uni_screen = new_uniscr;
 369 }
 370
 371 static void vc_uniscr_putc(struct vc_data *vc, char32_t uc)
 372 {
 373         struct uni_screen *uniscr = get_vc_uniscr(vc);
 374
 375         if (uniscr)
 376                 uniscr->lines[vc->state.y][vc->state.x] = uc;
 377 }
 378
 379 static void vc_uniscr_insert(struct vc_data *vc, unsigned int nr)
 380 {
 381         struct uni_screen *uniscr = get_vc_uniscr(vc);
 382
 383         if (uniscr) {
 384                 char32_t *ln = uniscr->lines[vc->state.y];
 385                 unsigned int x = vc->state.x, cols = vc->vc_cols;
 386
 387                 memmove(&ln[x + nr], &ln[x], (cols - x - nr) * sizeof(*ln));
 388                 memset32(&ln[x], ' ', nr);
 389         }
 390 }
 391
 392 static void vc_uniscr_delete(struct vc_data *vc, unsigned int nr)
 393 {
 394         struct uni_screen *uniscr = get_vc_uniscr(vc);
 395
 396         if (uniscr) {
 397                 char32_t *ln = uniscr->lines[vc->state.y];
 398                 unsigned int x = vc->state.x, cols = vc->vc_cols;
 399
 400                 memcpy(&ln[x], &ln[x + nr], (cols - x - nr) * sizeof(*ln));
 401                 memset32(&ln[cols - nr], ' ', nr);
 402         }
 403 }
 404
 405 static void vc_uniscr_clear_line(struct vc_data *vc, unsigned int x,
 406                                  unsigned int nr)
 407 {
 408         struct uni_screen *uniscr = get_vc_uniscr(vc);
 409
 410         if (uniscr) {
 411                 char32_t *ln = uniscr->lines[vc->state.y];
 412
 413                 memset32(&ln[x], ' ', nr);
 414         }
 415 }
 416
 417 static void vc_uniscr_clear_lines(struct vc_data *vc, unsigned int y,
 418                                   unsigned int nr)
 419 {
 420         struct uni_screen *uniscr = get_vc_uniscr(vc);
 421
 422         if (uniscr) {
 423                 unsigned int cols = vc->vc_cols;
 424
 425                 while (nr--)
 426                         memset32(uniscr->lines[y++], ' ', cols);
 427         }
 428 }
 429
 430 static void vc_uniscr_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
 431                              enum con_scroll dir, unsigned int nr)
 432 {
 433         struct uni_screen *uniscr = get_vc_uniscr(vc);
 434
 435         if (uniscr) {
 436                 unsigned int i, j, k, sz, d, clear;
 437
 438                 sz = b - t;
 439                 clear = b - nr;
 440                 d = nr;
 441                 if (dir == SM_DOWN) {
 442                         clear = t;
 443                         d = sz - nr;
 444                 }
 445                 for (i = 0; i < gcd(d, sz); i++) {
 446                         char32_t *tmp = uniscr->lines[t + i];
 447                         j = i;
 448                         while (1) {
 449                                 k = j + d;
 450                                 if (k >= sz)
 451                                         k -= sz;
 452                                 if (k == i)
 453                                         break;
 454                                 uniscr->lines[t + j] = uniscr->lines[t + k];
 455                                 j = k;
 456                         }
 457                         uniscr->lines[t + j] = tmp;
 458                 }
 459                 vc_uniscr_clear_lines(vc, clear, nr);
 460         }
 461 }
 462
 463 static void vc_uniscr_copy_area(struct uni_screen *dst,
 464                                 unsigned int dst_cols,
 465                                 unsigned int dst_rows,
 466                                 struct uni_screen *src,
 467                                 unsigned int src_cols,
 468                                 unsigned int src_top_row,
 469                                 unsigned int src_bot_row)
 470 {
 471         unsigned int dst_row = 0;
 472
 473         if (!dst)
 474                 return;
 475
 476         while (src_top_row < src_bot_row) {
 477                 char32_t *src_line = src->lines[src_top_row];
 478                 char32_t *dst_line = dst->lines[dst_row];
 479
 480                 memcpy(dst_line, src_line, src_cols * sizeof(char32_t));
 481                 if (dst_cols - src_cols)
 482                         memset32(dst_line + src_cols, ' ', dst_cols - src_cols);
 483                 src_top_row++;
 484                 dst_row++;
 485         }
 486         while (dst_row < dst_rows) {
 487                 char32_t *dst_line = dst->lines[dst_row];
 488
 489                 memset32(dst_line, ' ', dst_cols);
 490                 dst_row++;
 491         }
 492 }
 493
 494 /*
 495  * Called from vcs_read() to make sure unicode screen retrieval is possible.
 496  * This will initialize the unicode screen buffer if not already done.
 497  * This returns 0 if OK, or a negative error code otherwise.
 498  * In particular, -ENODATA is returned if the console is not in UTF-8 mode.
 499  */
 500 int vc_uniscr_check(struct vc_data *vc)
 501 {
 502         struct uni_screen *uniscr;
 503         unsigned short *p;
 504         int x, y, mask;
 505
 506         if (__is_defined(NO_VC_UNI_SCREEN))
 507                 return -EOPNOTSUPP;
 508
 509         WARN_CONSOLE_UNLOCKED();
 510
 511         if (!vc->vc_utf)
 512                 return -ENODATA;
 513
 514         if (vc->vc_uni_screen)
 515                 return 0;
 516
 517         uniscr = vc_uniscr_alloc(vc->vc_cols, vc->vc_rows);
 518         if (!uniscr)
 519                 return -ENOMEM;
 520
 521         /*
 522          * Let's populate it initially with (imperfect) reverse translation.
 523          * This is the next best thing we can do short of having it enabled
 524          * from the start even when no users rely on this functionality. True
 525          * unicode content will be available after a complete screen refresh.
 526          */
 527         p = (unsigned short *)vc->vc_origin;
 528         mask = vc->vc_hi_font_mask | 0xff;
 529         for (y = 0; y < vc->vc_rows; y++) {
 530                 char32_t *line = uniscr->lines[y];
 531                 for (x = 0; x < vc->vc_cols; x++) {
 532                         u16 glyph = scr_readw(p++) & mask;
 533                         line[x] = inverse_translate(vc, glyph, true);
 534                 }
 535         }
 536
 537         vc->vc_uni_screen = uniscr;
 538         return 0;
 539 }
 540
 541 /*
 542  * Called from vcs_read() to get the unicode data from the screen.
 543  * This must be preceded by a successful call to vc_uniscr_check() once
 544  * the console lock has been taken.
 545  */
 546 void vc_uniscr_copy_line(struct vc_data *vc, void *dest, int viewed,
 547                          unsigned int row, unsigned int col, unsigned int nr)
 548 {
 549         struct uni_screen *uniscr = get_vc_uniscr(vc);
 550         int offset = row * vc->vc_size_row + col * 2;
 551         unsigned long pos;
 552
 553         BUG_ON(!uniscr);
 554
 555         pos = (unsigned long)screenpos(vc, offset, viewed);
 556         if (pos >= vc->vc_origin && pos < vc->vc_scr_end) {
 557                 /*
 558                  * Desired position falls in the main screen buffer.
 559                  * However the actual row/col might be different if
 560                  * scrollback is active.
 561                  */
 562                 row = (pos - vc->vc_origin) / vc->vc_size_row;
 563                 col = ((pos - vc->vc_origin) % vc->vc_size_row) / 2;
 564                 memcpy(dest, &uniscr->lines[row][col], nr * sizeof(char32_t));
 565         } else {
 566                 /*
 567                  * Scrollback is active. For now let's simply backtranslate
 568                  * the screen glyphs until the unicode screen buffer does
 569                  * synchronize with console display drivers for a scrollback
 570                  * buffer of its own.
 571                  */
 572                 u16 *p = (u16 *)pos;
 573                 int mask = vc->vc_hi_font_mask | 0xff;
 574                 char32_t *uni_buf = dest;
 575                 while (nr--) {
 576                         u16 glyph = scr_readw(p++) & mask;
 577                         *uni_buf++ = inverse_translate(vc, glyph, true);
 578                 }
 579         }
 580 }
 581
 582 /* this is for validation and debugging only */
 583 static void vc_uniscr_debug_check(struct vc_data *vc)
 584 {
 585         struct uni_screen *uniscr = get_vc_uniscr(vc);
 586         unsigned short *p;
 587         int x, y, mask;
 588
 589         if (!VC_UNI_SCREEN_DEBUG || !uniscr)
 590                 return;
 591
 592         WARN_CONSOLE_UNLOCKED();
 593
 594         /*
 595          * Make sure our unicode screen translates into the same glyphs
 596          * as the actual screen. This is brutal indeed.
 597          */
 598         p = (unsigned short *)vc->vc_origin;
 599         mask = vc->vc_hi_font_mask | 0xff;
 600         for (y = 0; y < vc->vc_rows; y++) {
 601                 char32_t *line = uniscr->lines[y];
 602                 for (x = 0; x < vc->vc_cols; x++) {
 603                         u16 glyph = scr_readw(p++) & mask;
 604                         char32_t uc = line[x];
 605                         int tc = conv_uni_to_pc(vc, uc);
 606                         if (tc == -4)
 607                                 tc = conv_uni_to_pc(vc, 0xfffd);
 608                         if (tc == -4)
 609                                 tc = conv_uni_to_pc(vc, '?');
 610                         if (tc != glyph)
 611                                 pr_err_ratelimited(
 612                                         "%s: mismatch at %d,%d: glyph=%#x tc=%#x\n",
 613                                         __func__, x, y, glyph, tc);
 614                 }
 615         }
 616 }
 617
 618
 619 static void con_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
 620                 enum con_scroll dir, unsigned int nr)
 621 {
 622         u16 *clear, *d, *s;
 623
 624         if (t + nr >= b)
 625                 nr = b - t - 1;
 626         if (b > vc->vc_rows || t >= b || nr < 1)
 627                 return;
 628         vc_uniscr_scroll(vc, t, b, dir, nr);
 629         if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, t, b, dir, nr))
 630                 return;
 631
 632         s = clear = (u16 *)(vc->vc_origin + vc->vc_size_row * t);
 633         d = (u16 *)(vc->vc_origin + vc->vc_size_row * (t + nr));
 634
 635         if (dir == SM_UP) {
 636                 clear = s + (b - t - nr) * vc->vc_cols;
 637                 swap(s, d);
 638         }
 639         scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
 640         scr_memsetw(clear, vc->vc_video_erase_char, vc->vc_size_row * nr);
 641 }
 642
 643 static void do_update_region(struct vc_data *vc, unsigned long start, int count)
 644 {
 645         unsigned int xx, yy, offset;
 646         u16 *p;
 647
 648         p = (u16 *) start;
 649         if (!vc->vc_sw->con_getxy) {
 650                 offset = (start - vc->vc_origin) / 2;
 651                 xx = offset % vc->vc_cols;
 652                 yy = offset / vc->vc_cols;
 653         } else {
 654                 int nxx, nyy;
 655                 start = vc->vc_sw->con_getxy(vc, start, &nxx, &nyy);
 656                 xx = nxx; yy = nyy;
 657         }
 658         for(;;) {
 659                 u16 attrib = scr_readw(p) & 0xff00;
 660                 int startx = xx;
 661                 u16 *q = p;
 662                 while (xx < vc->vc_cols && count) {
 663                         if (attrib != (scr_readw(p) & 0xff00)) {
 664                                 if (p > q)
 665                                         vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
 666                                 startx = xx;
 667                                 q = p;
 668                                 attrib = scr_readw(p) & 0xff00;
 669                         }
 670                         p++;
 671                         xx++;
 672                         count--;
 673                 }
 674                 if (p > q)
 675                         vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
 676                 if (!count)
 677                         break;
 678                 xx = 0;
 679                 yy++;
 680                 if (vc->vc_sw->con_getxy) {
 681                         p = (u16 *)start;
 682                         start = vc->vc_sw->con_getxy(vc, start, NULL, NULL);
 683                 }
 684         }
 685 }
 686
 687 void update_region(struct vc_data *vc, unsigned long start, int count)
 688 {
 689         WARN_CONSOLE_UNLOCKED();
 690
 691         if (con_should_update(vc)) {
 692                 hide_cursor(vc);
 693                 do_update_region(vc, start, count);
 694                 set_cursor(vc);
 695         }
 696 }
 697
 698 /* Structure of attributes is hardware-dependent */
 699
 700 static u8 build_attr(struct vc_data *vc, u8 _color,
 701                 enum vc_intensity _intensity, bool _blink, bool _underline,
 702                 bool _reverse, bool _italic)
 703 {
 704         if (vc->vc_sw->con_build_attr)
 705                 return vc->vc_sw->con_build_attr(vc, _color, _intensity,
 706                        _blink, _underline, _reverse, _italic);
 707
 708 /*
 709  * ++roman: I completely changed the attribute format for monochrome
 710  * mode (!can_do_color). The formerly used MDA (monochrome display
 711  * adapter) format didn't allow the combination of certain effects.
 712  * Now the attribute is just a bit vector:
 713  *  Bit 0..1: intensity (0..2)
 714  *  Bit 2   : underline
 715  *  Bit 3   : reverse
 716  *  Bit 7   : blink
 717  */
 718         {
 719         u8 a = _color;
 720         if (!vc->vc_can_do_color)
 721                 return _intensity |
 722                        (_italic    << 1) |
 723                        (_underline << 2) |
 724                        (_reverse   << 3) |
 725                        (_blink     << 7);
 726         if (_italic)
 727                 a = (a & 0xF0) | vc->vc_itcolor;
 728         else if (_underline)
 729                 a = (a & 0xf0) | vc->vc_ulcolor;
 730         else if (_intensity == VCI_HALF_BRIGHT)
 731                 a = (a & 0xf0) | vc->vc_halfcolor;
 732         if (_reverse)
 733                 a = (a & 0x88) | (((a >> 4) | (a << 4)) & 0x77);
 734         if (_blink)
 735                 a ^= 0x80;
 736         if (_intensity == VCI_BOLD)
 737                 a ^= 0x08;
 738         if (vc->vc_hi_font_mask == 0x100)
 739                 a <<= 1;
 740         return a;
 741         }
 742 }
 743
 744 static void update_attr(struct vc_data *vc)
 745 {
 746         vc->vc_attr = build_attr(vc, vc->state.color, vc->state.intensity,
 747                       vc->state.blink, vc->state.underline,
 748                       vc->state.reverse ^ vc->vc_decscnm, vc->state.italic);
 749         vc->vc_video_erase_char = ' ' | (build_attr(vc, vc->state.color,
 750                                 VCI_NORMAL, vc->state.blink, false,
 751                                 vc->vc_decscnm, false) << 8);
 752 }
 753
 754 /* Note: inverting the screen twice should revert to the original state */
 755 void invert_screen(struct vc_data *vc, int offset, int count, int viewed)
 756 {
 757         unsigned short *p;
 758
 759         WARN_CONSOLE_UNLOCKED();
 760
 761         count /= 2;
 762         p = screenpos(vc, offset, viewed);
 763         if (vc->vc_sw->con_invert_region) {
 764                 vc->vc_sw->con_invert_region(vc, p, count);
 765         } else {
 766                 u16 *q = p;
 767                 int cnt = count;
 768                 u16 a;
 769
 770                 if (!vc->vc_can_do_color) {
 771                         while (cnt--) {
 772                             a = scr_readw(q);
 773                             a ^= 0x0800;
 774                             scr_writew(a, q);
 775                             q++;
 776                         }
 777                 } else if (vc->vc_hi_font_mask == 0x100) {
 778                         while (cnt--) {
 779                                 a = scr_readw(q);
 780                                 a = (a & 0x11ff) |
 781                                    ((a & 0xe000) >> 4) |
 782                                    ((a & 0x0e00) << 4);
 783                                 scr_writew(a, q);
 784                                 q++;
 785                         }
 786                 } else {
 787                         while (cnt--) {
 788                                 a = scr_readw(q);
 789                                 a = (a & 0x88ff) |
 790                                    ((a & 0x7000) >> 4) |
 791                                    ((a & 0x0700) << 4);
 792                                 scr_writew(a, q);
 793                                 q++;
 794                         }
 795                 }
 796         }
 797
 798         if (con_should_update(vc))
 799                 do_update_region(vc, (unsigned long) p, count);
 800         notify_update(vc);
 801 }
 802
 803 /* used by selection: complement pointer position */
 804 void complement_pos(struct vc_data *vc, int offset)
 805 {
 806         static int old_offset = -1;
 807         static unsigned short old;
 808         static unsigned short oldx, oldy;
 809
 810         WARN_CONSOLE_UNLOCKED();
 811
 812         if (old_offset != -1 && old_offset >= 0 &&
 813             old_offset < vc->vc_screenbuf_size) {
 814                 scr_writew(old, screenpos(vc, old_offset, 1));
 815                 if (con_should_update(vc))
 816                         vc->vc_sw->con_putc(vc, old, oldy, oldx);
 817                 notify_update(vc);
 818         }
 819
 820         old_offset = offset;
 821
 822         if (offset != -1 && offset >= 0 &&
 823             offset < vc->vc_screenbuf_size) {
 824                 unsigned short new;
 825                 unsigned short *p;
 826                 p = screenpos(vc, offset, 1);
 827                 old = scr_readw(p);
 828                 new = old ^ vc->vc_complement_mask;
 829                 scr_writew(new, p);
 830                 if (con_should_update(vc)) {
 831                         oldx = (offset >> 1) % vc->vc_cols;
 832                         oldy = (offset >> 1) / vc->vc_cols;
 833                         vc->vc_sw->con_putc(vc, new, oldy, oldx);
 834                 }
 835                 notify_update(vc);
 836         }
 837 }
 838
 839 static void insert_char(struct vc_data *vc, unsigned int nr)
 840 {
 841         unsigned short *p = (unsigned short *) vc->vc_pos;
 842
 843         vc_uniscr_insert(vc, nr);
 844         scr_memmovew(p + nr, p, (vc->vc_cols - vc->state.x - nr) * 2);
 845         scr_memsetw(p, vc->vc_video_erase_char, nr * 2);
 846         vc->vc_need_wrap = 0;
 847         if (con_should_update(vc))
 848                 do_update_region(vc, (unsigned long) p,
 849                         vc->vc_cols - vc->state.x);
 850 }
 851
 852 static void delete_char(struct vc_data *vc, unsigned int nr)
 853 {
 854         unsigned short *p = (unsigned short *) vc->vc_pos;
 855
 856         vc_uniscr_delete(vc, nr);
 857         scr_memcpyw(p, p + nr, (vc->vc_cols - vc->state.x - nr) * 2);
 858         scr_memsetw(p + vc->vc_cols - vc->state.x - nr, vc->vc_video_erase_char,
 859                         nr * 2);
 860         vc->vc_need_wrap = 0;
 861         if (con_should_update(vc))
 862                 do_update_region(vc, (unsigned long) p,
 863                         vc->vc_cols - vc->state.x);
 864 }
 865
 866 static int softcursor_original = -1;
 867
 868 static void add_softcursor(struct vc_data *vc)
 869 {
 870         int i = scr_readw((u16 *) vc->vc_pos);
 871         u32 type = vc->vc_cursor_type;
 872
 873         if (!(type & CUR_SW))
 874                 return;
 875         if (softcursor_original != -1)
 876                 return;
 877         softcursor_original = i;
 878         i |= CUR_SET(type);
 879         i ^= CUR_CHANGE(type);
 880         if ((type & CUR_ALWAYS_BG) &&
 881                         (softcursor_original & CUR_BG) == (i & CUR_BG))
 882                 i ^= CUR_BG;
 883         if ((type & CUR_INVERT_FG_BG) && (i & CUR_FG) == ((i & CUR_BG) >> 4))
 884                 i ^= CUR_FG;
 885         scr_writew(i, (u16 *)vc->vc_pos);
 886         if (con_should_update(vc))
 887                 vc->vc_sw->con_putc(vc, i, vc->state.y, vc->state.x);
 888 }
 889
 890 static void hide_softcursor(struct vc_data *vc)
 891 {
 892         if (softcursor_original != -1) {
 893                 scr_writew(softcursor_original, (u16 *)vc->vc_pos);
 894                 if (con_should_update(vc))
 895                         vc->vc_sw->con_putc(vc, softcursor_original,
 896                                         vc->state.y, vc->state.x);
 897                 softcursor_original = -1;
 898         }
 899 }
 900
 901 static void hide_cursor(struct vc_data *vc)
 902 {
 903         if (vc_is_sel(vc))
 904                 clear_selection();
 905
 906         vc->vc_sw->con_cursor(vc, CM_ERASE);
 907         hide_softcursor(vc);
 908 }
 909
 910 static void set_cursor(struct vc_data *vc)
 911 {
 912         if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS)
 913                 return;
 914         if (vc->vc_deccm) {
 915                 if (vc_is_sel(vc))
 916                         clear_selection();
 917                 add_softcursor(vc);
 918                 if (CUR_SIZE(vc->vc_cursor_type) != CUR_NONE)
 919                         vc->vc_sw->con_cursor(vc, CM_DRAW);
 920         } else
 921                 hide_cursor(vc);
 922 }
 923
 924 static void set_origin(struct vc_data *vc)
 925 {
 926         WARN_CONSOLE_UNLOCKED();
 927
 928         if (!con_is_visible(vc) ||
 929             !vc->vc_sw->con_set_origin ||
 930             !vc->vc_sw->con_set_origin(vc))
 931                 vc->vc_origin = (unsigned long)vc->vc_screenbuf;
 932         vc->vc_visible_origin = vc->vc_origin;
 933         vc->vc_scr_end = vc->vc_origin + vc->vc_screenbuf_size;
 934         vc->vc_pos = vc->vc_origin + vc->vc_size_row * vc->state.y +
 935                 2 * vc->state.x;
 936 }
 937
 938 static void save_screen(struct vc_data *vc)
 939 {
 940         WARN_CONSOLE_UNLOCKED();
 941
 942         if (vc->vc_sw->con_save_screen)
 943                 vc->vc_sw->con_save_screen(vc);
 944 }
 945
 946 static void flush_scrollback(struct vc_data *vc)
 947 {
 948         WARN_CONSOLE_UNLOCKED();
 949
 950         set_origin(vc);
 951         if (vc->vc_sw->con_flush_scrollback) {
 952                 vc->vc_sw->con_flush_scrollback(vc);
 953         } else if (con_is_visible(vc)) {
 954                 /*
 955                  * When no con_flush_scrollback method is provided then the
 956                  * legacy way for flushing the scrollback buffer is to use
 957                  * a side effect of the con_switch method. We do it only on
 958                  * the foreground console as background consoles have no
 959                  * scrollback buffers in that case and we obviously don't
 960                  * want to switch to them.
 961                  */
 962                 hide_cursor(vc);
 963                 vc->vc_sw->con_switch(vc);
 964                 set_cursor(vc);
 965         }
 966 }
 967
 968 /*
 969  *      Redrawing of screen
 970  */
 971
 972 void clear_buffer_attributes(struct vc_data *vc)
 973 {
 974         unsigned short *p = (unsigned short *)vc->vc_origin;
 975         int count = vc->vc_screenbuf_size / 2;
 976         int mask = vc->vc_hi_font_mask | 0xff;
 977
 978         for (; count > 0; count--, p++) {
 979                 scr_writew((scr_readw(p)&mask) | (vc->vc_video_erase_char & ~mask), p);
 980         }
 981 }
 982
 983 void redraw_screen(struct vc_data *vc, int is_switch)
 984 {
 985         int redraw = 0;
 986
 987         WARN_CONSOLE_UNLOCKED();
 988
 989         if (!vc) {
 990                 /* strange ... */
 991                 /* printk("redraw_screen: tty %d not allocated ??\n", new_console+1); */
 992                 return;
 993         }
 994
 995         if (is_switch) {
 996                 struct vc_data *old_vc = vc_cons[fg_console].d;
 997                 if (old_vc == vc)
 998                         return;
 999                 if (!con_is_visible(vc))
1000                         redraw = 1;
1001                 *vc->vc_display_fg = vc;
1002                 fg_console = vc->vc_num;
1003                 hide_cursor(old_vc);
1004                 if (!con_is_visible(old_vc)) {
1005                         save_screen(old_vc);
1006                         set_origin(old_vc);
1007                 }
1008                 if (tty0dev)
1009                         sysfs_notify(&tty0dev->kobj, NULL, "active");
1010         } else {
1011                 hide_cursor(vc);
1012                 redraw = 1;
1013         }
1014
1015         if (redraw) {
1016                 int update;
1017                 int old_was_color = vc->vc_can_do_color;
1018
1019                 set_origin(vc);
1020                 update = vc->vc_sw->con_switch(vc);
1021                 set_palette(vc);
1022                 /*
1023                  * If console changed from mono<->color, the best we can do
1024                  * is to clear the buffer attributes. As it currently stands,
1025                  * rebuilding new attributes from the old buffer is not doable
1026                  * without overly complex code.
1027                  */
1028                 if (old_was_color != vc->vc_can_do_color) {
1029                         update_attr(vc);
1030                         clear_buffer_attributes(vc);
1031                 }
1032
1033                 if (update && vc->vc_mode != KD_GRAPHICS)
1034                         do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
1035         }
1036         set_cursor(vc);
1037         if (is_switch) {
1038                 set_leds();
1039                 compute_shiftstate();
1040                 notify_update(vc);
1041         }
1042 }
1043
1044 /*
1045  *      Allocation, freeing and resizing of VTs.
1046  */
1047
1048 int vc_cons_allocated(unsigned int i)
1049 {
1050         return (i < MAX_NR_CONSOLES && vc_cons[i].d);
1051 }
1052
1053 static void visual_init(struct vc_data *vc, int num, int init)
1054 {
1055         /* ++Geert: vc->vc_sw->con_init determines console size */
1056         if (vc->vc_sw)
1057                 module_put(vc->vc_sw->owner);
1058         vc->vc_sw = conswitchp;
1059 #ifndef VT_SINGLE_DRIVER
1060         if (con_driver_map[num])
1061                 vc->vc_sw = con_driver_map[num];
1062 #endif
1063         __module_get(vc->vc_sw->owner);
1064         vc->vc_num = num;
1065         vc->vc_display_fg = &master_display_fg;
1066         if (vc->vc_uni_pagedir_loc)
1067                 con_free_unimap(vc);
1068         vc->vc_uni_pagedir_loc = &vc->vc_uni_pagedir;
1069         vc->vc_uni_pagedir = NULL;
1070         vc->vc_hi_font_mask = 0;
1071         vc->vc_complement_mask = 0;
1072         vc->vc_can_do_color = 0;
1073         vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1074         vc->vc_sw->con_init(vc, init);
1075         if (!vc->vc_complement_mask)
1076                 vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
1077         vc->vc_s_complement_mask = vc->vc_complement_mask;
1078         vc->vc_size_row = vc->vc_cols << 1;
1079         vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
1080 }
1081
1082
1083 static void visual_deinit(struct vc_data *vc)
1084 {
1085         vc->vc_sw->con_deinit(vc);
1086         module_put(vc->vc_sw->owner);
1087 }
1088
1089 static void vc_port_destruct(struct tty_port *port)
1090 {
1091         struct vc_data *vc = container_of(port, struct vc_data, port);
1092
1093         kfree(vc);
1094 }
1095
1096 static const struct tty_port_operations vc_port_ops = {
1097         .destruct = vc_port_destruct,
1098 };
1099
1100 /*
1101  * Change # of rows and columns (0 means unchanged/the size of fg_console)
1102  * [this is to be used together with some user program
1103  * like resize that changes the hardware videomode]
1104  */
1105 #define VC_MAXCOL (32767)
1106 #define VC_MAXROW (32767)
1107
1108 int vc_allocate(unsigned int currcons)  /* return 0 on success */
1109 {
1110         struct vt_notifier_param param;
1111         struct vc_data *vc;
1112         int err;
1113
1114         WARN_CONSOLE_UNLOCKED();
1115
1116         if (currcons >= MAX_NR_CONSOLES)
1117                 return -ENXIO;
1118
1119         if (vc_cons[currcons].d)
1120                 return 0;
1121
1122         /* due to the granularity of kmalloc, we waste some memory here */
1123         /* the alloc is done in two steps, to optimize the common situation
1124            of a 25x80 console (structsize=216, screenbuf_size=4000) */
1125         /* although the numbers above are not valid since long ago, the
1126            point is still up-to-date and the comment still has its value
1127            even if only as a historical artifact.  --mj, July 1998 */
1128         param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL);
1129         if (!vc)
1130                 return -ENOMEM;
1131
1132         vc_cons[currcons].d = vc;
1133         tty_port_init(&vc->port);
1134         vc->port.ops = &vc_port_ops;
1135         INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
1136
1137         visual_init(vc, currcons, 1);
1138
1139         if (!*vc->vc_uni_pagedir_loc)
1140                 con_set_default_unimap(vc);
1141
1142         err = -EINVAL;
1143         if (vc->vc_cols > VC_MAXCOL || vc->vc_rows > VC_MAXROW ||
1144             vc->vc_screenbuf_size > KMALLOC_MAX_SIZE || !vc->vc_screenbuf_size)
1145                 goto err_free;
1146         err = -ENOMEM;
1147         vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
1148         if (!vc->vc_screenbuf)
1149                 goto err_free;
1150
1151         /* If no drivers have overridden us and the user didn't pass a
1152            boot option, default to displaying the cursor */
1153         if (global_cursor_default == -1)
1154                 global_cursor_default = 1;
1155
1156         vc_init(vc, vc->vc_rows, vc->vc_cols, 1);
1157         vcs_make_sysfs(currcons);
1158         atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, &param);
1159
1160         return 0;
1161 err_free:
1162         visual_deinit(vc);
1163         kfree(vc);
1164         vc_cons[currcons].d = NULL;
1165         return err;
1166 }
1167
1168 static inline int resize_screen(struct vc_data *vc, int width, int height,
1169                                 int user)
1170 {
1171         /* Resizes the resolution of the display adapater */
1172         int err = 0;
1173
1174         if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_resize)
1175                 err = vc->vc_sw->con_resize(vc, width, height, user);
1176
1177         return err;
1178 }
1179
1180 /**
1181  *      vc_do_resize    -       resizing method for the tty
1182  *      @tty: tty being resized
1183  *      @real_tty: real tty (different to tty if a pty/tty pair)
1184  *      @vc: virtual console private data
1185  *      @cols: columns
1186  *      @lines: lines
1187  *
1188  *      Resize a virtual console, clipping according to the actual constraints.
1189  *      If the caller passes a tty structure then update the termios winsize
1190  *      information and perform any necessary signal handling.
1191  *
1192  *      Caller must hold the console semaphore. Takes the termios rwsem and
1193  *      ctrl_lock of the tty IFF a tty is passed.
1194  */
1195
1196 static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
1197                                 unsigned int cols, unsigned int lines)
1198 {
1199         unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
1200         unsigned long end;
1201         unsigned int old_rows, old_row_size, first_copied_row;
1202         unsigned int new_cols, new_rows, new_row_size, new_screen_size;
1203         unsigned int user;
1204         unsigned short *newscreen;
1205         struct uni_screen *new_uniscr = NULL;
1206
1207         WARN_CONSOLE_UNLOCKED();
1208
1209         if (!vc)
1210                 return -ENXIO;
1211
1212         user = vc->vc_resize_user;
1213         vc->vc_resize_user = 0;
1214
1215         if (cols > VC_MAXCOL || lines > VC_MAXROW)
1216                 return -EINVAL;
1217
1218         new_cols = (cols ? cols : vc->vc_cols);
1219         new_rows = (lines ? lines : vc->vc_rows);
1220         new_row_size = new_cols << 1;
1221         new_screen_size = new_row_size * new_rows;
1222
1223         if (new_cols == vc->vc_cols && new_rows == vc->vc_rows)
1224                 return 0;
1225
1226         if (new_screen_size > KMALLOC_MAX_SIZE || !new_screen_size)
1227                 return -EINVAL;
1228         newscreen = kzalloc(new_screen_size, GFP_USER);
1229         if (!newscreen)
1230                 return -ENOMEM;
1231
1232         if (get_vc_uniscr(vc)) {
1233                 new_uniscr = vc_uniscr_alloc(new_cols, new_rows);
1234                 if (!new_uniscr) {
1235                         kfree(newscreen);
1236                         return -ENOMEM;
1237                 }
1238         }
1239
1240         if (vc_is_sel(vc))
1241                 clear_selection();
1242
1243         old_rows = vc->vc_rows;
1244         old_row_size = vc->vc_size_row;
1245
1246         err = resize_screen(vc, new_cols, new_rows, user);
1247         if (err) {
1248                 kfree(newscreen);
1249                 vc_uniscr_free(new_uniscr);
1250                 return err;
1251         }
1252
1253         vc->vc_rows = new_rows;
1254         vc->vc_cols = new_cols;
1255         vc->vc_size_row = new_row_size;
1256         vc->vc_screenbuf_size = new_screen_size;
1257
1258         rlth = min(old_row_size, new_row_size);
1259         rrem = new_row_size - rlth;
1260         old_origin = vc->vc_origin;
1261         new_origin = (long) newscreen;
1262         new_scr_end = new_origin + new_screen_size;
1263
1264         if (vc->state.y > new_rows) {
1265                 if (old_rows - vc->state.y < new_rows) {
1266                         /*
1267                          * Cursor near the bottom, copy contents from the
1268                          * bottom of buffer
1269                          */
1270                         first_copied_row = (old_rows - new_rows);
1271                 } else {
1272                         /*
1273                          * Cursor is in no man's land, copy 1/2 screenful
1274                          * from the top and bottom of cursor position
1275                          */
1276                         first_copied_row = (vc->state.y - new_rows/2);
1277                 }
1278                 old_origin += first_copied_row * old_row_size;
1279         } else
1280                 first_copied_row = 0;
1281         end = old_origin + old_row_size * min(old_rows, new_rows);
1282
1283         vc_uniscr_copy_area(new_uniscr, new_cols, new_rows,
1284                             get_vc_uniscr(vc), rlth/2, first_copied_row,
1285                             min(old_rows, new_rows));
1286         vc_uniscr_set(vc, new_uniscr);
1287
1288         update_attr(vc);
1289
1290         while (old_origin < end) {
1291                 scr_memcpyw((unsigned short *) new_origin,
1292                             (unsigned short *) old_origin, rlth);
1293                 if (rrem)
1294                         scr_memsetw((void *)(new_origin + rlth),
1295                                     vc->vc_video_erase_char, rrem);
1296                 old_origin += old_row_size;
1297                 new_origin += new_row_size;
1298         }
1299         if (new_scr_end > new_origin)
1300                 scr_memsetw((void *)new_origin, vc->vc_video_erase_char,
1301                             new_scr_end - new_origin);
1302         kfree(vc->vc_screenbuf);
1303         vc->vc_screenbuf = newscreen;
1304         vc->vc_screenbuf_size = new_screen_size;
1305         set_origin(vc);
1306
1307         /* do part of a reset_terminal() */
1308         vc->vc_top = 0;
1309         vc->vc_bottom = vc->vc_rows;
1310         gotoxy(vc, vc->state.x, vc->state.y);
1311         save_cur(vc);
1312
1313         if (tty) {
1314                 /* Rewrite the requested winsize data with the actual
1315                    resulting sizes */
1316                 struct winsize ws;
1317                 memset(&ws, 0, sizeof(ws));
1318                 ws.ws_row = vc->vc_rows;
1319                 ws.ws_col = vc->vc_cols;
1320                 ws.ws_ypixel = vc->vc_scan_lines;
1321                 tty_do_resize(tty, &ws);
1322         }
1323
1324         if (con_is_visible(vc))
1325                 update_screen(vc);
1326         vt_event_post(VT_EVENT_RESIZE, vc->vc_num, vc->vc_num);
1327         notify_update(vc);
1328         return err;
1329 }
1330
1331 /**
1332  *      vc_resize               -       resize a VT
1333  *      @vc: virtual console
1334  *      @cols: columns
1335  *      @rows: rows
1336  *
1337  *      Resize a virtual console as seen from the console end of things. We
1338  *      use the common vc_do_resize methods to update the structures. The
1339  *      caller must hold the console sem to protect console internals and
1340  *      vc->port.tty
1341  */
1342
1343 int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
1344 {
1345         return vc_do_resize(vc->port.tty, vc, cols, rows);
1346 }
1347
1348 /**
1349  *      vt_resize               -       resize a VT
1350  *      @tty: tty to resize
1351  *      @ws: winsize attributes
1352  *
1353  *      Resize a virtual terminal. This is called by the tty layer as we
1354  *      register our own handler for resizing. The mutual helper does all
1355  *      the actual work.
1356  *
1357  *      Takes the console sem and the called methods then take the tty
1358  *      termios_rwsem and the tty ctrl_lock in that order.
1359  */
1360 static int vt_resize(struct tty_struct *tty, struct winsize *ws)
1361 {
1362         struct vc_data *vc = tty->driver_data;
1363         int ret;
1364
1365         console_lock();
1366         ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row);
1367         console_unlock();
1368         return ret;
1369 }
1370
1371 struct vc_data *vc_deallocate(unsigned int currcons)
1372 {
1373         struct vc_data *vc = NULL;
1374
1375         WARN_CONSOLE_UNLOCKED();
1376
1377         if (vc_cons_allocated(currcons)) {
1378                 struct vt_notifier_param param;
1379
1380                 param.vc = vc = vc_cons[currcons].d;
1381                 atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, &param);
1382                 vcs_remove_sysfs(currcons);
1383                 visual_deinit(vc);
1384                 put_pid(vc->vt_pid);
1385                 vc_uniscr_set(vc, NULL);
1386                 kfree(vc->vc_screenbuf);
1387                 vc_cons[currcons].d = NULL;
1388         }
1389         return vc;
1390 }
1391
1392 /*
1393  *      VT102 emulator
1394  */
1395
1396 enum { EPecma = 0, EPdec, EPeq, EPgt, EPlt};
1397
1398 #define set_kbd(vc, x)  vt_set_kbd_mode_bit((vc)->vc_num, (x))
1399 #define clr_kbd(vc, x)  vt_clr_kbd_mode_bit((vc)->vc_num, (x))
1400 #define is_kbd(vc, x)   vt_get_kbd_mode_bit((vc)->vc_num, (x))
1401
1402 #define decarm          VC_REPEAT
1403 #define decckm          VC_CKMODE
1404 #define kbdapplic       VC_APPLIC
1405 #define lnm             VC_CRLF
1406
1407 const unsigned char color_table[] = { 0, 4, 2, 6, 1, 5, 3, 7,
1408                                        8,12,10,14, 9,13,11,15 };
1409
1410 /* the default colour table, for VGA+ colour systems */
1411 unsigned char default_red[] = {
1412         0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa,
1413         0x55, 0xff, 0x55, 0xff, 0x55, 0xff, 0x55, 0xff
1414 };
1415 module_param_array(default_red, byte, NULL, S_IRUGO | S_IWUSR);
1416
1417 unsigned char default_grn[] = {
1418         0x00, 0x00, 0xaa, 0x55, 0x00, 0x00, 0xaa, 0xaa,
1419         0x55, 0x55, 0xff, 0xff, 0x55, 0x55, 0xff, 0xff
1420 };
1421 module_param_array(default_grn, byte, NULL, S_IRUGO | S_IWUSR);
1422
1423 unsigned char default_blu[] = {
1424         0x00, 0x00, 0x00, 0x00, 0xaa, 0xaa, 0xaa, 0xaa,
1425         0x55, 0x55, 0x55, 0x55, 0xff, 0xff, 0xff, 0xff
1426 };
1427 module_param_array(default_blu, byte, NULL, S_IRUGO | S_IWUSR);
1428
1429 /*
1430  * gotoxy() must verify all boundaries, because the arguments
1431  * might also be negative. If the given position is out of
1432  * bounds, the cursor is placed at the nearest margin.
1433  */
1434 static void gotoxy(struct vc_data *vc, int new_x, int new_y)
1435 {
1436         int min_y, max_y;
1437
1438         if (new_x < 0)
1439                 vc->state.x = 0;
1440         else {
1441                 if (new_x >= vc->vc_cols)
1442                         vc->state.x = vc->vc_cols - 1;
1443                 else
1444                         vc->state.x = new_x;
1445         }
1446
1447         if (vc->vc_decom) {
1448                 min_y = vc->vc_top;
1449                 max_y = vc->vc_bottom;
1450         } else {
1451                 min_y = 0;
1452                 max_y = vc->vc_rows;
1453         }
1454         if (new_y < min_y)
1455                 vc->state.y = min_y;
1456         else if (new_y >= max_y)
1457                 vc->state.y = max_y - 1;
1458         else
1459                 vc->state.y = new_y;
1460         vc->vc_pos = vc->vc_origin + vc->state.y * vc->vc_size_row +
1461                 (vc->state.x << 1);
1462         vc->vc_need_wrap = 0;
1463 }
1464
1465 /* for absolute user moves, when decom is set */
1466 static void gotoxay(struct vc_data *vc, int new_x, int new_y)
1467 {
1468         gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y);
1469 }
1470
1471 void scrollback(struct vc_data *vc)
1472 {
1473         scrolldelta(-(vc->vc_rows / 2));
1474 }
1475
1476 void scrollfront(struct vc_data *vc, int lines)
1477 {
1478         if (!lines)
1479                 lines = vc->vc_rows / 2;
1480         scrolldelta(lines);
1481 }
1482
1483 static void lf(struct vc_data *vc)
1484 {
1485         /* don't scroll if above bottom of scrolling region, or
1486          * if below scrolling region
1487          */
1488         if (vc->state.y + 1 == vc->vc_bottom)
1489                 con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_UP, 1);
1490         else if (vc->state.y < vc->vc_rows - 1) {
1491                 vc->state.y++;
1492                 vc->vc_pos += vc->vc_size_row;
1493         }
1494         vc->vc_need_wrap = 0;
1495         notify_write(vc, '\n');
1496 }
1497
1498 static void ri(struct vc_data *vc)
1499 {
1500         /* don't scroll if below top of scrolling region, or
1501          * if above scrolling region
1502          */
1503         if (vc->state.y == vc->vc_top)
1504                 con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_DOWN, 1);
1505         else if (vc->state.y > 0) {
1506                 vc->state.y--;
1507                 vc->vc_pos -= vc->vc_size_row;
1508         }
1509         vc->vc_need_wrap = 0;
1510 }
1511
1512 static inline void cr(struct vc_data *vc)
1513 {
1514         vc->vc_pos -= vc->state.x << 1;
1515         vc->vc_need_wrap = vc->state.x = 0;
1516         notify_write(vc, '\r');
1517 }
1518
1519 static inline void bs(struct vc_data *vc)
1520 {
1521         if (vc->state.x) {
1522                 vc->vc_pos -= 2;
1523                 vc->state.x--;
1524                 vc->vc_need_wrap = 0;
1525                 notify_write(vc, '\b');
1526         }
1527 }
1528
1529 static inline void del(struct vc_data *vc)
1530 {
1531         /* ignored */
1532 }
1533
1534 static void csi_J(struct vc_data *vc, int vpar)
1535 {
1536         unsigned int count;
1537         unsigned short * start;
1538
1539         switch (vpar) {
1540                 case 0: /* erase from cursor to end of display */
1541                         vc_uniscr_clear_line(vc, vc->state.x,
1542                                              vc->vc_cols - vc->state.x);
1543                         vc_uniscr_clear_lines(vc, vc->state.y + 1,
1544                                               vc->vc_rows - vc->state.y - 1);
1545                         count = (vc->vc_scr_end - vc->vc_pos) >> 1;
1546                         start = (unsigned short *)vc->vc_pos;
1547                         break;
1548                 case 1: /* erase from start to cursor */
1549                         vc_uniscr_clear_line(vc, 0, vc->state.x + 1);
1550                         vc_uniscr_clear_lines(vc, 0, vc->state.y);
1551                         count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1;
1552                         start = (unsigned short *)vc->vc_origin;
1553                         break;
1554                 case 3: /* include scrollback */
1555                         flush_scrollback(vc);
1556                         /* fallthrough */
1557                 case 2: /* erase whole display */
1558                         vc_uniscr_clear_lines(vc, 0, vc->vc_rows);
1559                         count = vc->vc_cols * vc->vc_rows;
1560                         start = (unsigned short *)vc->vc_origin;
1561                         break;
1562                 default:
1563                         return;
1564         }
1565         scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1566         if (con_should_update(vc))
1567                 do_update_region(vc, (unsigned long) start, count);
1568         vc->vc_need_wrap = 0;
1569 }
1570
1571 static void csi_K(struct vc_data *vc, int vpar)
1572 {
1573         unsigned int count;
1574         unsigned short *start = (unsigned short *)vc->vc_pos;
1575         int offset;
1576
1577         switch (vpar) {
1578                 case 0: /* erase from cursor to end of line */
1579                         offset = 0;
1580                         count = vc->vc_cols - vc->state.x;
1581                         break;
1582                 case 1: /* erase from start of line to cursor */
1583                         offset = -vc->state.x;
1584                         count = vc->state.x + 1;
1585                         break;
1586                 case 2: /* erase whole line */
1587                         offset = -vc->state.x;
1588                         count = vc->vc_cols;
1589                         break;
1590                 default:
1591                         return;
1592         }
1593         vc_uniscr_clear_line(vc, vc->state.x + offset, count);
1594         scr_memsetw(start + offset, vc->vc_video_erase_char, 2 * count);
1595         vc->vc_need_wrap = 0;
1596         if (con_should_update(vc))
1597                 do_update_region(vc, (unsigned long)(start + offset), count);
1598 }
1599
1600 /* erase the following vpar positions */
1601 static void csi_X(struct vc_data *vc, unsigned int vpar)
1602 {                                         /* not vt100? */
1603         unsigned int count;
1604
1605         if (!vpar)
1606                 vpar++;
1607
1608         count = min(vpar, vc->vc_cols - vc->state.x);
1609
1610         vc_uniscr_clear_line(vc, vc->state.x, count);
1611         scr_memsetw((unsigned short *)vc->vc_pos, vc->vc_video_erase_char, 2 * count);
1612         if (con_should_update(vc))
1613                 vc->vc_sw->con_clear(vc, vc->state.y, vc->state.x, 1, count);
1614         vc->vc_need_wrap = 0;
1615 }
1616
1617 static void default_attr(struct vc_data *vc)
1618 {
1619         vc->state.intensity = VCI_NORMAL;
1620         vc->state.italic = false;
1621         vc->state.underline = false;
1622         vc->state.reverse = false;
1623         vc->state.blink = false;
1624         vc->state.color = vc->vc_def_color;
1625 }
1626
1627 struct rgb { u8 r; u8 g; u8 b; };
1628
1629 static void rgb_from_256(int i, struct rgb *c)
1630 {
1631         if (i < 8) {            /* Standard colours. */
1632                 c->r = i&1 ? 0xaa : 0x00;
1633                 c->g = i&2 ? 0xaa : 0x00;
1634                 c->b = i&4 ? 0xaa : 0x00;
1635         } else if (i < 16) {
1636                 c->r = i&1 ? 0xff : 0x55;
1637                 c->g = i&2 ? 0xff : 0x55;
1638                 c->b = i&4 ? 0xff : 0x55;
1639         } else if (i < 232) {   /* 6x6x6 colour cube. */
1640                 c->r = (i - 16) / 36 * 85 / 2;
1641                 c->g = (i - 16) / 6 % 6 * 85 / 2;
1642                 c->b = (i - 16) % 6 * 85 / 2;
1643         } else                  /* Grayscale ramp. */
1644                 c->r = c->g = c->b = i * 10 - 2312;
1645 }
1646
1647 static void rgb_foreground(struct vc_data *vc, const struct rgb *c)
1648 {
1649         u8 hue = 0, max = max3(c->r, c->g, c->b);
1650
1651         if (c->r > max / 2)
1652                 hue |= 4;
1653         if (c->g > max / 2)
1654                 hue |= 2;
1655         if (c->b > max / 2)
1656                 hue |= 1;
1657
1658         if (hue == 7 && max <= 0x55) {
1659                 hue = 0;
1660                 vc->state.intensity = VCI_BOLD;
1661         } else if (max > 0xaa)
1662                 vc->state.intensity = VCI_BOLD;
1663         else
1664                 vc->state.intensity = VCI_NORMAL;
1665
1666         vc->state.color = (vc->state.color & 0xf0) | hue;
1667 }
1668
1669 static void rgb_background(struct vc_data *vc, const struct rgb *c)
1670 {
1671         /* For backgrounds, err on the dark side. */
1672         vc->state.color = (vc->state.color & 0x0f)
1673                 | (c->r&0x80) >> 1 | (c->g&0x80) >> 2 | (c->b&0x80) >> 3;
1674 }
1675
1676 /*
1677  * ITU T.416 Higher colour modes. They break the usual properties of SGR codes
1678  * and thus need to be detected and ignored by hand. That standard also
1679  * wants : rather than ; as separators but sequences containing : are currently
1680  * completely ignored by the parser.
1681  *
1682  * Subcommands 3 (CMY) and 4 (CMYK) are so insane there's no point in
1683  * supporting them.
1684  */
1685 static int vc_t416_color(struct vc_data *vc, int i,
1686                 void(*set_color)(struct vc_data *vc, const struct rgb *c))
1687 {
1688         struct rgb c;
1689
1690         i++;
1691         if (i > vc->vc_npar)
1692                 return i;
1693
1694         if (vc->vc_par[i] == 5 && i + 1 <= vc->vc_npar) {
1695                 /* 256 colours */
1696                 i++;
1697                 rgb_from_256(vc->vc_par[i], &c);
1698         } else if (vc->vc_par[i] == 2 && i + 3 <= vc->vc_npar) {
1699                 /* 24 bit */
1700                 c.r = vc->vc_par[i + 1];
1701                 c.g = vc->vc_par[i + 2];
1702                 c.b = vc->vc_par[i + 3];
1703                 i += 3;
1704         } else
1705                 return i;
1706
1707         set_color(vc, &c);
1708
1709         return i;
1710 }
1711
1712 /* console_lock is held */
1713 static void csi_m(struct vc_data *vc)
1714 {
1715         int i;
1716
1717         for (i = 0; i <= vc->vc_npar; i++)
1718                 switch (vc->vc_par[i]) {
1719                 case 0: /* all attributes off */
1720                         default_attr(vc);
1721                         break;
1722                 case 1:
1723                         vc->state.intensity = VCI_BOLD;
1724                         break;
1725                 case 2:
1726                         vc->state.intensity = VCI_HALF_BRIGHT;
1727                         break;
1728                 case 3:
1729                         vc->state.italic = true;
1730                         break;
1731                 case 21:
1732                         /*
1733                          * No console drivers support double underline, so
1734                          * convert it to a single underline.
1735                          */
1736                 case 4:
1737                         vc->state.underline = true;
1738                         break;
1739                 case 5:
1740                         vc->state.blink = true;
1741                         break;
1742                 case 7:
1743                         vc->state.reverse = true;
1744                         break;
1745                 case 10: /* ANSI X3.64-1979 (SCO-ish?)
1746                           * Select primary font, don't display control chars if
1747                           * defined, don't set bit 8 on output.
1748                           */
1749                         vc->vc_translate = set_translate(vc->state.Gx_charset[vc->state.charset], vc);
1750                         vc->vc_disp_ctrl = 0;
1751                         vc->vc_toggle_meta = 0;
1752                         break;
1753                 case 11: /* ANSI X3.64-1979 (SCO-ish?)
1754                           * Select first alternate font, lets chars < 32 be
1755                           * displayed as ROM chars.
1756                           */
1757                         vc->vc_translate = set_translate(IBMPC_MAP, vc);
1758                         vc->vc_disp_ctrl = 1;
1759                         vc->vc_toggle_meta = 0;
1760                         break;
1761                 case 12: /* ANSI X3.64-1979 (SCO-ish?)
1762                           * Select second alternate font, toggle high bit
1763                           * before displaying as ROM char.
1764                           */
1765                         vc->vc_translate = set_translate(IBMPC_MAP, vc);
1766                         vc->vc_disp_ctrl = 1;
1767                         vc->vc_toggle_meta = 1;
1768                         break;
1769                 case 22:
1770                         vc->state.intensity = VCI_NORMAL;
1771                         break;
1772                 case 23:
1773                         vc->state.italic = false;
1774                         break;
1775                 case 24:
1776                         vc->state.underline = false;
1777                         break;
1778                 case 25:
1779                         vc->state.blink = false;
1780                         break;
1781                 case 27:
1782                         vc->state.reverse = false;
1783                         break;
1784                 case 38:
1785                         i = vc_t416_color(vc, i, rgb_foreground);
1786                         break;
1787                 case 48:
1788                         i = vc_t416_color(vc, i, rgb_background);
1789                         break;
1790                 case 39:
1791                         vc->state.color = (vc->vc_def_color & 0x0f) |
1792                                 (vc->state.color & 0xf0);
1793                         break;
1794                 case 49:
1795                         vc->state.color = (vc->vc_def_color & 0xf0) |
1796                                 (vc->state.color & 0x0f);
1797                         break;
1798                 default:
1799                         if (vc->vc_par[i] >= 90 && vc->vc_par[i] <= 107) {
1800                                 if (vc->vc_par[i] < 100)
1801                                         vc->state.intensity = VCI_BOLD;
1802                                 vc->vc_par[i] -= 60;
1803                         }
1804                         if (vc->vc_par[i] >= 30 && vc->vc_par[i] <= 37)
1805                                 vc->state.color = color_table[vc->vc_par[i] - 30]
1806                                         | (vc->state.color & 0xf0);
1807                         else if (vc->vc_par[i] >= 40 && vc->vc_par[i] <= 47)
1808                                 vc->state.color = (color_table[vc->vc_par[i] - 40] << 4)
1809                                         | (vc->state.color & 0x0f);
1810                         break;
1811                 }
1812         update_attr(vc);
1813 }
1814
1815 static void respond_string(const char *p, size_t len, struct tty_port *port)
1816 {
1817         tty_insert_flip_string(port, p, len);
1818         tty_schedule_flip(port);
1819 }
1820
1821 static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
1822 {
1823         char buf[40];
1824         int len;
1825
1826         len = sprintf(buf, "\033[%d;%dR", vc->state.y +
1827                         (vc->vc_decom ? vc->vc_top + 1 : 1),
1828                         vc->state.x + 1);
1829         respond_string(buf, len, tty->port);
1830 }
1831
1832 static inline void status_report(struct tty_struct *tty)
1833 {
1834         static const char teminal_ok[] = "\033[0n";
1835
1836         respond_string(teminal_ok, strlen(teminal_ok), tty->port);
1837 }
1838
1839 static inline void respond_ID(struct tty_struct *tty)
1840 {
1841         /* terminal answer to an ESC-Z or csi0c query. */
1842         static const char vt102_id[] = "\033[?6c";
1843
1844         respond_string(vt102_id, strlen(vt102_id), tty->port);
1845 }
1846
1847 void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
1848 {
1849         char buf[8];
1850         int len;
1851
1852         len = sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt),
1853                         (char)('!' + mrx), (char)('!' + mry));
1854         respond_string(buf, len, tty->port);
1855 }
1856
1857 /* invoked via ioctl(TIOCLINUX) and through set_selection_user */
1858 int mouse_reporting(void)
1859 {
1860         return vc_cons[fg_console].d->vc_report_mouse;
1861 }
1862
1863 /* console_lock is held */
1864 static void set_mode(struct vc_data *vc, int on_off)
1865 {
1866         int i;
1867
1868         for (i = 0; i <= vc->vc_npar; i++)
1869                 if (vc->vc_priv == EPdec) {
1870                         switch(vc->vc_par[i]) { /* DEC private modes set/reset */
1871                         case 1:                 /* Cursor keys send ^[Ox/^[[x */
1872                                 if (on_off)
1873                                         set_kbd(vc, decckm);
1874                                 else
1875                                         clr_kbd(vc, decckm);
1876                                 break;
1877                         case 3: /* 80/132 mode switch unimplemented */
1878 #if 0
1879                                 vc_resize(deccolm ? 132 : 80, vc->vc_rows);
1880                                 /* this alone does not suffice; some user mode
1881                                    utility has to change the hardware regs */
1882 #endif
1883                                 break;
1884                         case 5:                 /* Inverted screen on/off */
1885                                 if (vc->vc_decscnm != on_off) {
1886                                         vc->vc_decscnm = on_off;
1887                                         invert_screen(vc, 0, vc->vc_screenbuf_size, 0);
1888                                         update_attr(vc);
1889                                 }
1890                                 break;
1891                         case 6:                 /* Origin relative/absolute */
1892                                 vc->vc_decom = on_off;
1893                                 gotoxay(vc, 0, 0);
1894                                 break;
1895                         case 7:                 /* Autowrap on/off */
1896                                 vc->vc_decawm = on_off;
1897                                 break;
1898                         case 8:                 /* Autorepeat on/off */
1899                                 if (on_off)
1900                                         set_kbd(vc, decarm);
1901                                 else
1902                                         clr_kbd(vc, decarm);
1903                                 break;
1904                         case 9:
1905                                 vc->vc_report_mouse = on_off ? 1 : 0;
1906                                 break;
1907                         case 25:                /* Cursor on/off */
1908                                 vc->vc_deccm = on_off;
1909                                 break;
1910                         case 1000:
1911                                 vc->vc_report_mouse = on_off ? 2 : 0;
1912                                 break;
1913                         }
1914                 } else {
1915                         switch(vc->vc_par[i]) { /* ANSI modes set/reset */
1916                         case 3:                 /* Monitor (display ctrls) */
1917                                 vc->vc_disp_ctrl = on_off;
1918                                 break;
1919                         case 4:                 /* Insert Mode on/off */
1920                                 vc->vc_decim = on_off;
1921                                 break;
1922                         case 20:                /* Lf, Enter == CrLf/Lf */
1923                                 if (on_off)
1924                                         set_kbd(vc, lnm);
1925                                 else
1926                                         clr_kbd(vc, lnm);
1927                                 break;
1928                         }
1929                 }
1930 }
1931
1932 /* console_lock is held */
1933 static void setterm_command(struct vc_data *vc)
1934 {
1935         switch (vc->vc_par[0]) {
1936         case 1: /* set color for underline mode */
1937                 if (vc->vc_can_do_color && vc->vc_par[1] < 16) {
1938                         vc->vc_ulcolor = color_table[vc->vc_par[1]];
1939                         if (vc->state.underline)
1940                                 update_attr(vc);
1941                 }
1942                 break;
1943         case 2: /* set color for half intensity mode */
1944                 if (vc->vc_can_do_color && vc->vc_par[1] < 16) {
1945                         vc->vc_halfcolor = color_table[vc->vc_par[1]];
1946                         if (vc->state.intensity == VCI_HALF_BRIGHT)
1947                                 update_attr(vc);
1948                 }
1949                 break;
1950         case 8: /* store colors as defaults */
1951                 vc->vc_def_color = vc->vc_attr;
1952                 if (vc->vc_hi_font_mask == 0x100)
1953                         vc->vc_def_color >>= 1;
1954                 default_attr(vc);
1955                 update_attr(vc);
1956                 break;
1957         case 9: /* set blanking interval */
1958                 blankinterval = min(vc->vc_par[1], 60U) * 60;
1959                 poke_blanked_console();
1960                 break;
1961         case 10: /* set bell frequency in Hz */
1962                 if (vc->vc_npar >= 1)
1963                         vc->vc_bell_pitch = vc->vc_par[1];
1964                 else
1965                         vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
1966                 break;
1967         case 11: /* set bell duration in msec */
1968                 if (vc->vc_npar >= 1)
1969                         vc->vc_bell_duration = (vc->vc_par[1] < 2000) ?
1970                                 msecs_to_jiffies(vc->vc_par[1]) : 0;
1971                 else
1972                         vc->vc_bell_duration = DEFAULT_BELL_DURATION;
1973                 break;
1974         case 12: /* bring specified console to the front */
1975                 if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1))
1976                         set_console(vc->vc_par[1] - 1);
1977                 break;
1978         case 13: /* unblank the screen */
1979                 poke_blanked_console();
1980                 break;
1981         case 14: /* set vesa powerdown interval */
1982                 vesa_off_interval = min(vc->vc_par[1], 60U) * 60 * HZ;
1983                 break;
1984         case 15: /* activate the previous console */
1985                 set_console(last_console);
1986                 break;
1987         case 16: /* set cursor blink duration in msec */
1988                 if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 &&
1989                                 vc->vc_par[1] <= USHRT_MAX)
1990                         vc->vc_cur_blink_ms = vc->vc_par[1];
1991                 else
1992                         vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1993                 break;
1994         }
1995 }
1996
1997 /* console_lock is held */
1998 static void csi_at(struct vc_data *vc, unsigned int nr)
1999 {
2000         if (nr > vc->vc_cols - vc->state.x)
2001                 nr = vc->vc_cols - vc->state.x;
2002         else if (!nr)
2003                 nr = 1;
2004         insert_char(vc, nr);
2005 }
2006
2007 /* console_lock is held */
2008 static void csi_L(struct vc_data *vc, unsigned int nr)
2009 {
2010         if (nr > vc->vc_rows - vc->state.y)
2011                 nr = vc->vc_rows - vc->state.y;
2012         else if (!nr)
2013                 nr = 1;
2014         con_scroll(vc, vc->state.y, vc->vc_bottom, SM_DOWN, nr);
2015         vc->vc_need_wrap = 0;
2016 }
2017
2018 /* console_lock is held */
2019 static void csi_P(struct vc_data *vc, unsigned int nr)
2020 {
2021         if (nr > vc->vc_cols - vc->state.x)
2022                 nr = vc->vc_cols - vc->state.x;
2023         else if (!nr)
2024                 nr = 1;
2025         delete_char(vc, nr);
2026 }
2027
2028 /* console_lock is held */
2029 static void csi_M(struct vc_data *vc, unsigned int nr)
2030 {
2031         if (nr > vc->vc_rows - vc->state.y)
2032                 nr = vc->vc_rows - vc->state.y;
2033         else if (!nr)
2034                 nr=1;
2035         con_scroll(vc, vc->state.y, vc->vc_bottom, SM_UP, nr);
2036         vc->vc_need_wrap = 0;
2037 }
2038
2039 /* console_lock is held (except via vc_init->reset_terminal */
2040 static void save_cur(struct vc_data *vc)
2041 {
2042         memcpy(&vc->saved_state, &vc->state, sizeof(vc->state));
2043 }
2044
2045 /* console_lock is held */
2046 static void restore_cur(struct vc_data *vc)
2047 {
2048         memcpy(&vc->state, &vc->saved_state, sizeof(vc->state));
2049
2050         gotoxy(vc, vc->state.x, vc->state.y);
2051         vc->vc_translate = set_translate(vc->state.Gx_charset[vc->state.charset],
2052                         vc);
2053         update_attr(vc);
2054         vc->vc_need_wrap = 0;
2055 }
2056
2057 enum { ESnormal, ESesc, ESsquare, ESgetpars, ESfunckey,
2058         EShash, ESsetG0, ESsetG1, ESpercent, EScsiignore, ESnonstd,
2059         ESpalette, ESosc };
2060
2061 /* console_lock is held (except via vc_init()) */
2062 static void reset_terminal(struct vc_data *vc, int do_clear)
2063 {
2064         unsigned int i;
2065
2066         vc->vc_top              = 0;
2067         vc->vc_bottom           = vc->vc_rows;
2068         vc->vc_state            = ESnormal;
2069         vc->vc_priv             = EPecma;
2070         vc->vc_translate        = set_translate(LAT1_MAP, vc);
2071         vc->state.Gx_charset[0] = LAT1_MAP;
2072         vc->state.Gx_charset[1] = GRAF_MAP;
2073         vc->state.charset       = 0;
2074         vc->vc_need_wrap        = 0;
2075         vc->vc_report_mouse     = 0;
2076         vc->vc_utf              = default_utf8;
2077         vc->vc_utf_count        = 0;
2078
2079         vc->vc_disp_ctrl        = 0;
2080         vc->vc_toggle_meta      = 0;
2081
2082         vc->vc_decscnm          = 0;
2083         vc->vc_decom            = 0;
2084         vc->vc_decawm           = 1;
2085         vc->vc_deccm            = global_cursor_default;
2086         vc->vc_decim            = 0;
2087
2088         vt_reset_keyboard(vc->vc_num);
2089
2090         vc->vc_cursor_type = cur_default;
2091         vc->vc_complement_mask = vc->vc_s_complement_mask;
2092
2093         default_attr(vc);
2094         update_attr(vc);
2095
2096         bitmap_zero(vc->vc_tab_stop, VC_TABSTOPS_COUNT);
2097         for (i = 0; i < VC_TABSTOPS_COUNT; i += 8)
2098                 set_bit(i, vc->vc_tab_stop);
2099
2100         vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
2101         vc->vc_bell_duration = DEFAULT_BELL_DURATION;
2102         vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
2103
2104         gotoxy(vc, 0, 0);
2105         save_cur(vc);
2106         if (do_clear)
2107             csi_J(vc, 2);
2108 }
2109
2110 static void vc_setGx(struct vc_data *vc, unsigned int which, int c)
2111 {
2112         unsigned char *charset = &vc->state.Gx_charset[which];
2113
2114         switch (c) {
2115         case '0':
2116                 *charset = GRAF_MAP;
2117                 break;
2118         case 'B':
2119                 *charset = LAT1_MAP;
2120                 break;
2121         case 'U':
2122                 *charset = IBMPC_MAP;
2123                 break;
2124         case 'K':
2125                 *charset = USER_MAP;
2126                 break;
2127         }
2128
2129         if (vc->state.charset == which)
2130                 vc->vc_translate = set_translate(*charset, vc);
2131 }
2132
2133 /* console_lock is held */
2134 static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
2135 {
2136         /*
2137          *  Control characters can be used in the _middle_
2138          *  of an escape sequence.
2139          */
2140         if (vc->vc_state == ESosc && c>=8 && c<=13) /* ... except for OSC */
2141                 return;
2142         switch (c) {
2143         case 0:
2144                 return;
2145         case 7:
2146                 if (vc->vc_state == ESosc)
2147                         vc->vc_state = ESnormal;
2148                 else if (vc->vc_bell_duration)
2149                         kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration);
2150                 return;
2151         case 8:
2152                 bs(vc);
2153                 return;
2154         case 9:
2155                 vc->vc_pos -= (vc->state.x << 1);
2156
2157                 vc->state.x = find_next_bit(vc->vc_tab_stop,
2158                                 min(vc->vc_cols - 1, VC_TABSTOPS_COUNT),
2159                                 vc->state.x + 1);
2160                 if (vc->state.x >= VC_TABSTOPS_COUNT)
2161                         vc->state.x = vc->vc_cols - 1;
2162
2163                 vc->vc_pos += (vc->state.x << 1);
2164                 notify_write(vc, '\t');
2165                 return;
2166         case 10: case 11: case 12:
2167                 lf(vc);
2168                 if (!is_kbd(vc, lnm))
2169                         return;
2170                 /* fall through */
2171         case 13:
2172                 cr(vc);
2173                 return;
2174         case 14:
2175                 vc->state.charset = 1;
2176                 vc->vc_translate = set_translate(vc->state.Gx_charset[1], vc);
2177                 vc->vc_disp_ctrl = 1;
2178                 return;
2179         case 15:
2180                 vc->state.charset = 0;
2181                 vc->vc_translate = set_translate(vc->state.Gx_charset[0], vc);
2182                 vc->vc_disp_ctrl = 0;
2183                 return;
2184         case 24: case 26:
2185                 vc->vc_state = ESnormal;
2186                 return;
2187         case 27:
2188                 vc->vc_state = ESesc;
2189                 return;
2190         case 127:
2191                 del(vc);
2192                 return;
2193         case 128+27:
2194                 vc->vc_state = ESsquare;
2195                 return;
2196         }
2197         switch(vc->vc_state) {
2198         case ESesc:
2199                 vc->vc_state = ESnormal;
2200                 switch (c) {
2201                 case '[':
2202                         vc->vc_state = ESsquare;
2203                         return;
2204                 case ']':
2205                         vc->vc_state = ESnonstd;
2206                         return;
2207                 case '%':
2208                         vc->vc_state = ESpercent;
2209                         return;
2210                 case 'E':
2211                         cr(vc);
2212                         lf(vc);
2213                         return;
2214                 case 'M':
2215                         ri(vc);
2216                         return;
2217                 case 'D':
2218                         lf(vc);
2219                         return;
2220                 case 'H':
2221                         if (vc->state.x < VC_TABSTOPS_COUNT)
2222                                 set_bit(vc->state.x, vc->vc_tab_stop);
2223                         return;
2224                 case 'Z':
2225                         respond_ID(tty);
2226                         return;
2227                 case '7':
2228                         save_cur(vc);
2229                         return;
2230                 case '8':
2231                         restore_cur(vc);
2232                         return;
2233                 case '(':
2234                         vc->vc_state = ESsetG0;
2235                         return;
2236                 case ')':
2237                         vc->vc_state = ESsetG1;
2238                         return;
2239                 case '#':
2240                         vc->vc_state = EShash;
2241                         return;
2242                 case 'c':
2243                         reset_terminal(vc, 1);
2244                         return;
2245                 case '>':  /* Numeric keypad */
2246                         clr_kbd(vc, kbdapplic);
2247                         return;
2248                 case '=':  /* Appl. keypad */
2249                         set_kbd(vc, kbdapplic);
2250                         return;
2251                 }
2252                 return;
2253         case ESnonstd:
2254                 if (c=='P') {   /* palette escape sequence */
2255                         for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2256                                 vc->vc_par[vc->vc_npar] = 0;
2257                         vc->vc_npar = 0;
2258                         vc->vc_state = ESpalette;
2259                         return;
2260                 } else if (c=='R') {   /* reset palette */
2261                         reset_palette(vc);
2262                         vc->vc_state = ESnormal;
2263                 } else if (c>='0' && c<='9')
2264                         vc->vc_state = ESosc;
2265                 else
2266                         vc->vc_state = ESnormal;
2267                 return;
2268         case ESpalette:
2269                 if (isxdigit(c)) {
2270                         vc->vc_par[vc->vc_npar++] = hex_to_bin(c);
2271                         if (vc->vc_npar == 7) {
2272                                 int i = vc->vc_par[0] * 3, j = 1;
2273                                 vc->vc_palette[i] = 16 * vc->vc_par[j++];
2274                                 vc->vc_palette[i++] += vc->vc_par[j++];
2275                                 vc->vc_palette[i] = 16 * vc->vc_par[j++];
2276                                 vc->vc_palette[i++] += vc->vc_par[j++];
2277                                 vc->vc_palette[i] = 16 * vc->vc_par[j++];
2278                                 vc->vc_palette[i] += vc->vc_par[j];
2279                                 set_palette(vc);
2280                                 vc->vc_state = ESnormal;
2281                         }
2282                 } else
2283                         vc->vc_state = ESnormal;
2284                 return;
2285         case ESsquare:
2286                 for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2287                         vc->vc_par[vc->vc_npar] = 0;
2288                 vc->vc_npar = 0;
2289                 vc->vc_state = ESgetpars;
2290                 if (c == '[') { /* Function key */
2291                         vc->vc_state=ESfunckey;
2292                         return;
2293                 }
2294                 switch (c) {
2295                 case '?':
2296                         vc->vc_priv = EPdec;
2297                         return;
2298                 case '>':
2299                         vc->vc_priv = EPgt;
2300                         return;
2301                 case '=':
2302                         vc->vc_priv = EPeq;
2303                         return;
2304                 case '<':
2305                         vc->vc_priv = EPlt;
2306                         return;
2307                 }
2308                 vc->vc_priv = EPecma;
2309                 /* fall through */
2310         case ESgetpars:
2311                 if (c == ';' && vc->vc_npar < NPAR - 1) {
2312                         vc->vc_npar++;
2313                         return;
2314                 } else if (c>='0' && c<='9') {
2315                         vc->vc_par[vc->vc_npar] *= 10;
2316                         vc->vc_par[vc->vc_npar] += c - '0';
2317                         return;
2318                 }
2319                 if (c >= 0x20 && c <= 0x3f) { /* 0x2x, 0x3a and 0x3c - 0x3f */
2320                         vc->vc_state = EScsiignore;
2321                         return;
2322                 }
2323                 vc->vc_state = ESnormal;
2324                 switch(c) {
2325                 case 'h':
2326                         if (vc->vc_priv <= EPdec)
2327                                 set_mode(vc, 1);
2328                         return;
2329                 case 'l':
2330                         if (vc->vc_priv <= EPdec)
2331                                 set_mode(vc, 0);
2332                         return;
2333                 case 'c':
2334                         if (vc->vc_priv == EPdec) {
2335                                 if (vc->vc_par[0])
2336                                         vc->vc_cursor_type =
2337                                                 CUR_MAKE(vc->vc_par[0],
2338                                                          vc->vc_par[1],
2339                                                          vc->vc_par[2]);
2340                                 else
2341                                         vc->vc_cursor_type = cur_default;
2342                                 return;
2343                         }
2344                         break;
2345                 case 'm':
2346                         if (vc->vc_priv == EPdec) {
2347                                 clear_selection();
2348                                 if (vc->vc_par[0])
2349                                         vc->vc_complement_mask = vc->vc_par[0] << 8 | vc->vc_par[1];
2350                                 else
2351                                         vc->vc_complement_mask = vc->vc_s_complement_mask;
2352                                 return;
2353                         }
2354                         break;
2355                 case 'n':
2356                         if (vc->vc_priv == EPecma) {
2357                                 if (vc->vc_par[0] == 5)
2358                                         status_report(tty);
2359                                 else if (vc->vc_par[0] == 6)
2360                                         cursor_report(vc, tty);
2361                         }
2362                         return;
2363                 }
2364                 if (vc->vc_priv != EPecma) {
2365                         vc->vc_priv = EPecma;
2366                         return;
2367                 }
2368                 switch(c) {
2369                 case 'G': case '`':
2370                         if (vc->vc_par[0])
2371                                 vc->vc_par[0]--;
2372                         gotoxy(vc, vc->vc_par[0], vc->state.y);
2373                         return;
2374                 case 'A':
2375                         if (!vc->vc_par[0])
2376                                 vc->vc_par[0]++;
2377                         gotoxy(vc, vc->state.x, vc->state.y - vc->vc_par[0]);
2378                         return;
2379                 case 'B': case 'e':
2380                         if (!vc->vc_par[0])
2381                                 vc->vc_par[0]++;
2382                         gotoxy(vc, vc->state.x, vc->state.y + vc->vc_par[0]);
2383                         return;
2384                 case 'C': case 'a':
2385                         if (!vc->vc_par[0])
2386                                 vc->vc_par[0]++;
2387                         gotoxy(vc, vc->state.x + vc->vc_par[0], vc->state.y);
2388                         return;
2389                 case 'D':
2390                         if (!vc->vc_par[0])
2391                                 vc->vc_par[0]++;
2392                         gotoxy(vc, vc->state.x - vc->vc_par[0], vc->state.y);
2393                         return;
2394                 case 'E':
2395                         if (!vc->vc_par[0])
2396                                 vc->vc_par[0]++;
2397                         gotoxy(vc, 0, vc->state.y + vc->vc_par[0]);
2398                         return;
2399                 case 'F':
2400                         if (!vc->vc_par[0])
2401                                 vc->vc_par[0]++;
2402                         gotoxy(vc, 0, vc->state.y - vc->vc_par[0]);
2403                         return;
2404                 case 'd':
2405                         if (vc->vc_par[0])
2406                                 vc->vc_par[0]--;
2407                         gotoxay(vc, vc->state.x ,vc->vc_par[0]);
2408                         return;
2409                 case 'H': case 'f':
2410                         if (vc->vc_par[0])
2411                                 vc->vc_par[0]--;
2412                         if (vc->vc_par[1])
2413                                 vc->vc_par[1]--;
2414                         gotoxay(vc, vc->vc_par[1], vc->vc_par[0]);
2415                         return;
2416                 case 'J':
2417                         csi_J(vc, vc->vc_par[0]);
2418                         return;
2419                 case 'K':
2420                         csi_K(vc, vc->vc_par[0]);
2421                         return;
2422                 case 'L':
2423                         csi_L(vc, vc->vc_par[0]);
2424                         return;
2425                 case 'M':
2426                         csi_M(vc, vc->vc_par[0]);
2427                         return;
2428                 case 'P':
2429                         csi_P(vc, vc->vc_par[0]);
2430                         return;
2431                 case 'c':
2432                         if (!vc->vc_par[0])
2433                                 respond_ID(tty);
2434                         return;
2435                 case 'g':
2436                         if (!vc->vc_par[0] && vc->state.x < VC_TABSTOPS_COUNT)
2437                                 set_bit(vc->state.x, vc->vc_tab_stop);
2438                         else if (vc->vc_par[0] == 3)
2439                                 bitmap_zero(vc->vc_tab_stop, VC_TABSTOPS_COUNT);
2440                         return;
2441                 case 'm':
2442                         csi_m(vc);
2443                         return;
2444                 case 'q': /* DECLL - but only 3 leds */
2445                         /* map 0,1,2,3 to 0,1,2,4 */
2446                         if (vc->vc_par[0] < 4)
2447                                 vt_set_led_state(vc->vc_num,
2448                                             (vc->vc_par[0] < 3) ? vc->vc_par[0] : 4);
2449                         return;
2450                 case 'r':
2451                         if (!vc->vc_par[0])
2452                                 vc->vc_par[0]++;
2453                         if (!vc->vc_par[1])
2454                                 vc->vc_par[1] = vc->vc_rows;
2455                         /* Minimum allowed region is 2 lines */
2456                         if (vc->vc_par[0] < vc->vc_par[1] &&
2457                             vc->vc_par[1] <= vc->vc_rows) {
2458                                 vc->vc_top = vc->vc_par[0] - 1;
2459                                 vc->vc_bottom = vc->vc_par[1];
2460                                 gotoxay(vc, 0, 0);
2461                         }
2462                         return;
2463                 case 's':
2464                         save_cur(vc);
2465                         return;
2466                 case 'u':
2467                         restore_cur(vc);
2468                         return;
2469                 case 'X':
2470                         csi_X(vc, vc->vc_par[0]);
2471                         return;
2472                 case '@':
2473                         csi_at(vc, vc->vc_par[0]);
2474                         return;
2475                 case ']': /* setterm functions */
2476                         setterm_command(vc);
2477                         return;
2478                 }
2479                 return;
2480         case EScsiignore:
2481                 if (c >= 20 && c <= 0x3f)
2482                         return;
2483                 vc->vc_state = ESnormal;
2484                 return;
2485         case ESpercent:
2486                 vc->vc_state = ESnormal;
2487                 switch (c) {
2488                 case '@':  /* defined in ISO 2022 */
2489                         vc->vc_utf = 0;
2490                         return;
2491                 case 'G':  /* prelim official escape code */
2492                 case '8':  /* retained for compatibility */
2493                         vc->vc_utf = 1;
2494                         return;
2495                 }
2496                 return;
2497         case ESfunckey:
2498                 vc->vc_state = ESnormal;
2499                 return;
2500         case EShash:
2501                 vc->vc_state = ESnormal;
2502                 if (c == '8') {
2503                         /* DEC screen alignment test. kludge :-) */
2504                         vc->vc_video_erase_char =
2505                                 (vc->vc_video_erase_char & 0xff00) | 'E';
2506                         csi_J(vc, 2);
2507                         vc->vc_video_erase_char =
2508                                 (vc->vc_video_erase_char & 0xff00) | ' ';
2509                         do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
2510                 }
2511                 return;
2512         case ESsetG0:
2513                 vc_setGx(vc, 0, c);
2514                 vc->vc_state = ESnormal;
2515                 return;
2516         case ESsetG1:
2517                 vc_setGx(vc, 1, c);
2518                 vc->vc_state = ESnormal;
2519                 return;
2520         case ESosc:
2521                 return;
2522         default:
2523                 vc->vc_state = ESnormal;
2524         }
2525 }
2526
2527 /* is_double_width() is based on the wcwidth() implementation by
2528  * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
2529  * Latest version: https://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
2530  */
2531 struct interval {
2532         uint32_t first;
2533         uint32_t last;
2534 };
2535
2536 static int ucs_cmp(const void *key, const void *elt)
2537 {
2538         uint32_t ucs = *(uint32_t *)key;
2539         struct interval e = *(struct interval *) elt;
2540
2541         if (ucs > e.last)
2542                 return 1;
2543         else if (ucs < e.first)
2544                 return -1;
2545         return 0;
2546 }
2547
2548 static int is_double_width(uint32_t ucs)
2549 {
2550         static const struct interval double_width[] = {
2551                 { 0x1100, 0x115F }, { 0x2329, 0x232A }, { 0x2E80, 0x303E },
2552                 { 0x3040, 0xA4CF }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF },
2553                 { 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 },
2554                 { 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }
2555         };
2556         if (ucs < double_width[0].first ||
2557             ucs > double_width[ARRAY_SIZE(double_width) - 1].last)
2558                 return 0;
2559
2560         return bsearch(&ucs, double_width, ARRAY_SIZE(double_width),
2561                         sizeof(struct interval), ucs_cmp) != NULL;
2562 }
2563
2564 struct vc_draw_region {
2565         unsigned long from, to;
2566         int x;
2567 };
2568
2569 static void con_flush(struct vc_data *vc, struct vc_draw_region *draw)
2570 {
2571         if (draw->x < 0)
2572                 return;
2573
2574         vc->vc_sw->con_putcs(vc, (u16 *)draw->from,
2575                         (u16 *)draw->to - (u16 *)draw->from, vc->state.y,
2576                         draw->x);
2577         draw->x = -1;
2578 }
2579
2580 static inline int vc_translate_ascii(const struct vc_data *vc, int c)
2581 {
2582         if (IS_ENABLED(CONFIG_CONSOLE_TRANSLATIONS)) {
2583                 if (vc->vc_toggle_meta)
2584                         c |= 0x80;
2585
2586                 return vc->vc_translate[c];
2587         }
2588
2589         return c;
2590 }
2591
2592
2593 /**
2594  * vc_sanitize_unicode -- Replace invalid Unicode code points with U+FFFD
2595  * @c: the received character, or U+FFFD for invalid sequences.
2596  */
2597 static inline int vc_sanitize_unicode(const int c)
2598 {
2599         if ((c >= 0xd800 && c <= 0xdfff) || c == 0xfffe || c == 0xffff)
2600                 return 0xfffd;
2601
2602         return c;
2603 }
2604
2605 /**
2606  * vc_translate_unicode -- Combine UTF-8 into Unicode in @vc_utf_char
2607  *
2608  * @vc_utf_char is the being-constructed unicode character.
2609  * @vc_utf_count is the number of continuation bytes still expected to arrive.
2610  * @vc_npar is the number of continuation bytes arrived so far.
2611  */
2612 static int vc_translate_unicode(struct vc_data *vc, int c, bool *rescan)
2613 {
2614         static const u32 utf8_length_changes[] = {
2615                 0x0000007f, 0x000007ff, 0x0000ffff,
2616                 0x001fffff, 0x03ffffff, 0x7fffffff
2617         };
2618
2619         /* Continuation byte received */
2620         if ((c & 0xc0) == 0x80) {
2621                 /* Unexpected continuation byte? */
2622                 if (!vc->vc_utf_count)
2623                         return 0xfffd;
2624
2625                 vc->vc_utf_char = (vc->vc_utf_char << 6) | (c & 0x3f);
2626                 vc->vc_npar++;
2627                 if (--vc->vc_utf_count)
2628                         goto need_more_bytes;
2629
2630                 /* Got a whole character */
2631                 c = vc->vc_utf_char;
2632                 /* Reject overlong sequences */
2633                 if (c <= utf8_length_changes[vc->vc_npar - 1] ||
2634                                 c > utf8_length_changes[vc->vc_npar])
2635                         return 0xfffd;
2636
2637                 return vc_sanitize_unicode(c);
2638         }
2639
2640         /* Single ASCII byte or first byte of a sequence received */
2641         if (vc->vc_utf_count) {
2642                 /* Continuation byte expected */
2643                 *rescan = true;
2644                 vc->vc_utf_count = 0;
2645                 return 0xfffd;
2646         }
2647
2648         /* Nothing to do if an ASCII byte was received */
2649         if (c <= 0x7f)
2650                 return c;
2651
2652         /* First byte of a multibyte sequence received */
2653         vc->vc_npar = 0;
2654         if ((c & 0xe0) == 0xc0) {
2655                 vc->vc_utf_count = 1;
2656                 vc->vc_utf_char = (c & 0x1f);
2657         } else if ((c & 0xf0) == 0xe0) {
2658                 vc->vc_utf_count = 2;
2659                 vc->vc_utf_char = (c & 0x0f);
2660         } else if ((c & 0xf8) == 0xf0) {
2661                 vc->vc_utf_count = 3;
2662                 vc->vc_utf_char = (c & 0x07);
2663         } else if ((c & 0xfc) == 0xf8) {
2664                 vc->vc_utf_count = 4;
2665                 vc->vc_utf_char = (c & 0x03);
2666         } else if ((c & 0xfe) == 0xfc) {
2667                 vc->vc_utf_count = 5;
2668                 vc->vc_utf_char = (c & 0x01);
2669         } else {
2670                 /* 254 and 255 are invalid */
2671                 return 0xfffd;
2672         }
2673
2674 need_more_bytes:
2675         return -1;
2676 }
2677
2678 static int vc_translate(struct vc_data *vc, int *c, bool *rescan)
2679 {
2680         /* Do no translation at all in control states */
2681         if (vc->vc_state != ESnormal)
2682                 return *c;
2683
2684         if (vc->vc_utf && !vc->vc_disp_ctrl)
2685                 return *c = vc_translate_unicode(vc, *c, rescan);
2686
2687         /* no utf or alternate charset mode */
2688         return vc_translate_ascii(vc, *c);
2689 }
2690
2691 static inline unsigned char vc_invert_attr(const struct vc_data *vc)
2692 {
2693         if (!vc->vc_can_do_color)
2694                 return vc->vc_attr ^ 0x08;
2695
2696         if (vc->vc_hi_font_mask == 0x100)
2697                 return   (vc->vc_attr & 0x11) |
2698                         ((vc->vc_attr & 0xe0) >> 4) |
2699                         ((vc->vc_attr & 0x0e) << 4);
2700
2701         return   (vc->vc_attr & 0x88) |
2702                 ((vc->vc_attr & 0x70) >> 4) |
2703                 ((vc->vc_attr & 0x07) << 4);
2704 }
2705
2706 static bool vc_is_control(struct vc_data *vc, int tc, int c)
2707 {
2708         /*
2709          * A bitmap for codes <32. A bit of 1 indicates that the code
2710          * corresponding to that bit number invokes some special action (such
2711          * as cursor movement) and should not be displayed as a glyph unless
2712          * the disp_ctrl mode is explicitly enabled.
2713          */
2714         static const u32 CTRL_ACTION = 0x0d00ff81;
2715         /* Cannot be overridden by disp_ctrl */
2716         static const u32 CTRL_ALWAYS = 0x0800f501;
2717
2718         if (vc->vc_state != ESnormal)
2719                 return true;
2720
2721         if (!tc)
2722                 return true;
2723
2724         /*
2725          * If the original code was a control character we only allow a glyph
2726          * to be displayed if the code is not normally used (such as for cursor
2727          * movement) or if the disp_ctrl mode has been explicitly enabled.
2728          * Certain characters (as given by the CTRL_ALWAYS bitmap) are always
2729          * displayed as control characters, as the console would be pretty
2730          * useless without them; to display an arbitrary font position use the
2731          * direct-to-font zone in UTF-8 mode.
2732          */
2733         if (c < 32) {
2734                 if (vc->vc_disp_ctrl)
2735                         return CTRL_ALWAYS & BIT(c);
2736                 else
2737                         return vc->vc_utf || (CTRL_ACTION & BIT(c));
2738         }
2739
2740         if (c == 127 && !vc->vc_disp_ctrl)
2741                 return true;
2742
2743         if (c == 128 + 27)
2744                 return true;
2745
2746         return false;
2747 }
2748
2749 static int vc_con_write_normal(struct vc_data *vc, int tc, int c,
2750                 struct vc_draw_region *draw)
2751 {
2752         int next_c;
2753         unsigned char vc_attr = vc->vc_attr;
2754         u16 himask = vc->vc_hi_font_mask, charmask = himask ? 0x1ff : 0xff;
2755         u8 width = 1;
2756         bool inverse = false;
2757
2758         if (vc->vc_utf && !vc->vc_disp_ctrl) {
2759                 if (is_double_width(c))
2760                         width = 2;
2761         }
2762
2763         /* Now try to find out how to display it */
2764         tc = conv_uni_to_pc(vc, tc);
2765         if (tc & ~charmask) {
2766                 if (tc == -1 || tc == -2)
2767                         return -1; /* nothing to display */
2768
2769                 /* Glyph not found */
2770                 if ((!vc->vc_utf || vc->vc_disp_ctrl || c < 128) &&
2771                                 !(c & ~charmask)) {
2772                         /*
2773                          * In legacy mode use the glyph we get by a 1:1
2774                          * mapping.
2775                          * This would make absolutely no sense with Unicode in
2776                          * mind, but do this for ASCII characters since a font
2777                          * may lack Unicode mapping info and we don't want to
2778                          * end up with having question marks only.
2779                          */
2780                         tc = c;
2781                 } else {
2782                         /*
2783                          * Display U+FFFD. If it's not found, display an inverse
2784                          * question mark.
2785                          */
2786                         tc = conv_uni_to_pc(vc, 0xfffd);
2787                         if (tc < 0) {
2788                                 inverse = true;
2789                                 tc = conv_uni_to_pc(vc, '?');
2790                                 if (tc < 0)
2791                                         tc = '?';
2792
2793                                 vc_attr = vc_invert_attr(vc);
2794                                 con_flush(vc, draw);
2795                         }
2796                 }
2797         }
2798
2799         next_c = c;
2800         while (1) {
2801                 if (vc->vc_need_wrap || vc->vc_decim)
2802                         con_flush(vc, draw);
2803                 if (vc->vc_need_wrap) {
2804                         cr(vc);
2805                         lf(vc);
2806                 }
2807                 if (vc->vc_decim)
2808                         insert_char(vc, 1);
2809                 vc_uniscr_putc(vc, next_c);
2810
2811                 if (himask)
2812                         tc = ((tc & 0x100) ? himask : 0) |
2813                               (tc &  0xff);
2814                 tc |= (vc_attr << 8) & ~himask;
2815
2816                 scr_writew(tc, (u16 *)vc->vc_pos);
2817
2818                 if (con_should_update(vc) && draw->x < 0) {
2819                         draw->x = vc->state.x;
2820                         draw->from = vc->vc_pos;
2821                 }
2822                 if (vc->state.x == vc->vc_cols - 1) {
2823                         vc->vc_need_wrap = vc->vc_decawm;
2824                         draw->to = vc->vc_pos + 2;
2825                 } else {
2826                         vc->state.x++;
2827                         draw->to = (vc->vc_pos += 2);
2828                 }
2829
2830                 if (!--width)
2831                         break;
2832
2833                 /* A space is printed in the second column */
2834                 tc = conv_uni_to_pc(vc, ' ');
2835                 if (tc < 0)
2836                         tc = ' ';
2837                 next_c = ' ';
2838         }
2839         notify_write(vc, c);
2840
2841         if (inverse)
2842                 con_flush(vc, draw);
2843
2844         return 0;
2845 }
2846
2847 /* acquires console_lock */
2848 static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int count)
2849 {
2850         struct vc_draw_region draw = {
2851                 .x = -1,
2852         };
2853         int c, tc, n = 0;
2854         unsigned int currcons;
2855         struct vc_data *vc;
2856         struct vt_notifier_param param;
2857         bool rescan;
2858
2859         if (in_interrupt())
2860                 return count;
2861
2862         console_lock();
2863         vc = tty->driver_data;
2864         if (vc == NULL) {
2865                 pr_err("vt: argh, driver_data is NULL !\n");
2866                 console_unlock();
2867                 return 0;
2868         }
2869
2870         currcons = vc->vc_num;
2871         if (!vc_cons_allocated(currcons)) {
2872                 /* could this happen? */
2873                 pr_warn_once("con_write: tty %d not allocated\n", currcons+1);
2874                 console_unlock();
2875                 return 0;
2876         }
2877
2878
2879         /* undraw cursor first */
2880         if (con_is_fg(vc))
2881                 hide_cursor(vc);
2882
2883         param.vc = vc;
2884
2885         while (!tty->stopped && count) {
2886                 int orig = *buf;
2887                 buf++;
2888                 n++;
2889                 count--;
2890 rescan_last_byte:
2891                 c = orig;
2892                 rescan = false;
2893
2894                 tc = vc_translate(vc, &c, &rescan);
2895                 if (tc == -1)
2896                         continue;
2897
2898                 param.c = tc;
2899                 if (atomic_notifier_call_chain(&vt_notifier_list, VT_PREWRITE,
2900                                         &param) == NOTIFY_STOP)
2901                         continue;
2902
2903                 if (vc_is_control(vc, tc, c)) {
2904                         con_flush(vc, &draw);
2905                         do_con_trol(tty, vc, orig);
2906                         continue;
2907                 }
2908
2909                 if (vc_con_write_normal(vc, tc, c, &draw) < 0)
2910                         continue;
2911
2912                 if (rescan)
2913                         goto rescan_last_byte;
2914         }
2915         con_flush(vc, &draw);
2916         vc_uniscr_debug_check(vc);
2917         console_conditional_schedule();
2918         notify_update(vc);
2919         console_unlock();
2920         return n;
2921 }
2922
2923 /*
2924  * This is the console switching callback.
2925  *
2926  * Doing console switching in a process context allows
2927  * us to do the switches asynchronously (needed when we want
2928  * to switch due to a keyboard interrupt).  Synchronization
2929  * with other console code and prevention of re-entrancy is
2930  * ensured with console_lock.
2931  */
2932 static void console_callback(struct work_struct *ignored)
2933 {
2934         console_lock();
2935
2936         if (want_console >= 0) {
2937                 if (want_console != fg_console &&
2938                     vc_cons_allocated(want_console)) {
2939                         hide_cursor(vc_cons[fg_console].d);
2940                         change_console(vc_cons[want_console].d);
2941                         /* we only changed when the console had already
2942                            been allocated - a new console is not created
2943                            in an interrupt routine */
2944                 }
2945                 want_console = -1;
2946         }
2947         if (do_poke_blanked_console) { /* do not unblank for a LED change */
2948                 do_poke_blanked_console = 0;
2949                 poke_blanked_console();
2950         }
2951         if (scrollback_delta) {
2952                 struct vc_data *vc = vc_cons[fg_console].d;
2953                 clear_selection();
2954                 if (vc->vc_mode == KD_TEXT && vc->vc_sw->con_scrolldelta)
2955                         vc->vc_sw->con_scrolldelta(vc, scrollback_delta);
2956                 scrollback_delta = 0;
2957         }
2958         if (blank_timer_expired) {
2959                 do_blank_screen(0);
2960                 blank_timer_expired = 0;
2961         }
2962         notify_update(vc_cons[fg_console].d);
2963
2964         console_unlock();
2965 }
2966
2967 int set_console(int nr)
2968 {
2969         struct vc_data *vc = vc_cons[fg_console].d;
2970
2971         if (!vc_cons_allocated(nr) || vt_dont_switch ||
2972                 (vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) {
2973
2974                 /*
2975                  * Console switch will fail in console_callback() or
2976                  * change_console() so there is no point scheduling
2977                  * the callback
2978                  *
2979                  * Existing set_console() users don't check the return
2980                  * value so this shouldn't break anything
2981                  */
2982                 return -EINVAL;
2983         }
2984
2985         want_console = nr;
2986         schedule_console_callback();
2987
2988         return 0;
2989 }
2990
2991 struct tty_driver *console_driver;
2992
2993 #ifdef CONFIG_VT_CONSOLE
2994
2995 /**
2996  * vt_kmsg_redirect() - Sets/gets the kernel message console
2997  * @new:        The new virtual terminal number or -1 if the console should stay
2998  *              unchanged
2999  *
3000  * By default, the kernel messages are always printed on the current virtual
3001  * console. However, the user may modify that default with the
3002  * TIOCL_SETKMSGREDIRECT ioctl call.
3003  *
3004  * This function sets the kernel message console to be @new. It returns the old
3005  * virtual console number. The virtual terminal number 0 (both as parameter and
3006  * return value) means no redirection (i.e. always printed on the currently
3007  * active console).
3008  *
3009  * The parameter -1 means that only the current console is returned, but the
3010  * value is not modified. You may use the macro vt_get_kmsg_redirect() in that
3011  * case to make the code more understandable.
3012  *
3013  * When the kernel is compiled without CONFIG_VT_CONSOLE, this function ignores
3014  * the parameter and always returns 0.
3015  */
3016 int vt_kmsg_redirect(int new)
3017 {
3018         static int kmsg_con;
3019
3020         if (new != -1)
3021                 return xchg(&kmsg_con, new);
3022         else
3023                 return kmsg_con;
3024 }
3025
3026 /*
3027  *      Console on virtual terminal
3028  *
3029  * The console must be locked when we get here.
3030  */
3031
3032 static void vt_console_print(struct console *co, const char *b, unsigned count)
3033 {
3034         struct vc_data *vc = vc_cons[fg_console].d;
3035         unsigned char c;
3036         static DEFINE_SPINLOCK(printing_lock);
3037         const ushort *start;
3038         ushort start_x, cnt;
3039         int kmsg_console;
3040
3041         /* console busy or not yet initialized */
3042         if (!printable)
3043                 return;
3044         if (!spin_trylock(&printing_lock))
3045                 return;
3046
3047         kmsg_console = vt_get_kmsg_redirect();
3048         if (kmsg_console && vc_cons_allocated(kmsg_console - 1))
3049                 vc = vc_cons[kmsg_console - 1].d;
3050
3051         if (!vc_cons_allocated(fg_console)) {
3052                 /* impossible */
3053                 /* printk("vt_console_print: tty %d not allocated ??\n", currcons+1); */
3054                 goto quit;
3055         }
3056
3057         if (vc->vc_mode != KD_TEXT)
3058                 goto quit;
3059
3060         /* undraw cursor first */
3061         if (con_is_fg(vc))
3062                 hide_cursor(vc);
3063
3064         start = (ushort *)vc->vc_pos;
3065         start_x = vc->state.x;
3066         cnt = 0;
3067         while (count--) {
3068                 c = *b++;
3069                 if (c == 10 || c == 13 || c == 8 || vc->vc_need_wrap) {
3070                         if (cnt && con_is_visible(vc))
3071                                 vc->vc_sw->con_putcs(vc, start, cnt, vc->state.y, start_x);
3072                         cnt = 0;
3073                         if (c == 8) {           /* backspace */
3074                                 bs(vc);
3075                                 start = (ushort *)vc->vc_pos;
3076                                 start_x = vc->state.x;
3077                                 continue;
3078                         }
3079                         if (c != 13)
3080                                 lf(vc);
3081                         cr(vc);
3082                         start = (ushort *)vc->vc_pos;
3083                         start_x = vc->state.x;
3084                         if (c == 10 || c == 13)
3085                                 continue;
3086                 }
3087                 vc_uniscr_putc(vc, c);
3088                 scr_writew((vc->vc_attr << 8) + c, (unsigned short *)vc->vc_pos);
3089                 notify_write(vc, c);
3090                 cnt++;
3091                 if (vc->state.x == vc->vc_cols - 1) {
3092                         vc->vc_need_wrap = 1;
3093                 } else {
3094                         vc->vc_pos += 2;
3095                         vc->state.x++;
3096                 }
3097         }
3098         if (cnt && con_is_visible(vc))
3099                 vc->vc_sw->con_putcs(vc, start, cnt, vc->state.y, start_x);
3100         set_cursor(vc);
3101         notify_update(vc);
3102
3103 quit:
3104         spin_unlock(&printing_lock);
3105 }
3106
3107 static struct tty_driver *vt_console_device(struct console *c, int *index)
3108 {
3109         *index = c->index ? c->index-1 : fg_console;
3110         return console_driver;
3111 }
3112
3113 static struct console vt_console_driver = {
3114         .name           = "tty",
3115         .write          = vt_console_print,
3116         .device         = vt_console_device,
3117         .unblank        = unblank_screen,
3118         .flags          = CON_PRINTBUFFER,
3119         .index          = -1,
3120 };
3121 #endif
3122
3123 /*
3124  *      Handling of Linux-specific VC ioctls
3125  */
3126
3127 /*
3128  * Generally a bit racy with respect to console_lock();.
3129  *
3130  * There are some functions which don't need it.
3131  *
3132  * There are some functions which can sleep for arbitrary periods
3133  * (paste_selection) but we don't need the lock there anyway.
3134  *
3135  * set_selection_user has locking, and definitely needs it
3136  */
3137
3138 int tioclinux(struct tty_struct *tty, unsigned long arg)
3139 {
3140         char type, data;
3141         char __user *p = (char __user *)arg;
3142         int lines;
3143         int ret;
3144
3145         if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
3146                 return -EPERM;
3147         if (get_user(type, p))
3148                 return -EFAULT;
3149         ret = 0;
3150
3151         switch (type)
3152         {
3153                 case TIOCL_SETSEL:
3154                         ret = set_selection_user((struct tiocl_selection
3155                                                  __user *)(p+1), tty);
3156                         break;
3157                 case TIOCL_PASTESEL:
3158                         ret = paste_selection(tty);
3159                         break;
3160                 case TIOCL_UNBLANKSCREEN:
3161                         console_lock();
3162                         unblank_screen();
3163                         console_unlock();
3164                         break;
3165                 case TIOCL_SELLOADLUT:
3166                         console_lock();
3167                         ret = sel_loadlut(p);
3168                         console_unlock();
3169                         break;
3170                 case TIOCL_GETSHIFTSTATE:
3171
3172         /*
3173          * Make it possible to react to Shift+Mousebutton.
3174          * Note that 'shift_state' is an undocumented
3175          * kernel-internal variable; programs not closely
3176          * related to the kernel should not use this.
3177          */
3178                         data = vt_get_shift_state();
3179                         ret = put_user(data, p);
3180                         break;
3181                 case TIOCL_GETMOUSEREPORTING:
3182                         console_lock(); /* May be overkill */
3183                         data = mouse_reporting();
3184                         console_unlock();
3185                         ret = put_user(data, p);
3186                         break;
3187                 case TIOCL_SETVESABLANK:
3188                         console_lock();
3189                         ret = set_vesa_blanking(p);
3190                         console_unlock();
3191                         break;
3192                 case TIOCL_GETKMSGREDIRECT:
3193                         data = vt_get_kmsg_redirect();
3194                         ret = put_user(data, p);
3195                         break;
3196                 case TIOCL_SETKMSGREDIRECT:
3197                         if (!capable(CAP_SYS_ADMIN)) {
3198                                 ret = -EPERM;
3199                         } else {
3200                                 if (get_user(data, p+1))
3201                                         ret = -EFAULT;
3202                                 else
3203                                         vt_kmsg_redirect(data);
3204                         }
3205                         break;
3206                 case TIOCL_GETFGCONSOLE:
3207                         /* No locking needed as this is a transiently
3208                            correct return anyway if the caller hasn't
3209                            disabled switching */
3210                         ret = fg_console;
3211                         break;
3212                 case TIOCL_SCROLLCONSOLE:
3213                         if (get_user(lines, (s32 __user *)(p+4))) {
3214                                 ret = -EFAULT;
3215                         } else {
3216                                 /* Need the console lock here. Note that lots
3217                                    of other calls need fixing before the lock
3218                                    is actually useful ! */
3219                                 console_lock();
3220                                 scrollfront(vc_cons[fg_console].d, lines);
3221                                 console_unlock();
3222                                 ret = 0;
3223                         }
3224                         break;
3225                 case TIOCL_BLANKSCREEN: /* until explicitly unblanked, not only poked */
3226                         console_lock();
3227                         ignore_poke = 1;
3228                         do_blank_screen(0);
3229                         console_unlock();
3230                         break;
3231                 case TIOCL_BLANKEDSCREEN:
3232                         ret = console_blanked;
3233                         break;
3234                 default:
3235                         ret = -EINVAL;
3236                         break;
3237         }
3238         return ret;
3239 }
3240
3241 /*
3242  * /dev/ttyN handling
3243  */
3244
3245 static int con_write(struct tty_struct *tty, const unsigned char *buf, int count)
3246 {
3247         int     retval;
3248
3249         retval = do_con_write(tty, buf, count);
3250         con_flush_chars(tty);
3251
3252         return retval;
3253 }
3254
3255 static int con_put_char(struct tty_struct *tty, unsigned char ch)
3256 {
3257         if (in_interrupt())
3258                 return 0;       /* n_r3964 calls put_char() from interrupt context */
3259         return do_con_write(tty, &ch, 1);
3260 }
3261
3262 static int con_write_room(struct tty_struct *tty)
3263 {
3264         if (tty->stopped)
3265                 return 0;
3266         return 32768;           /* No limit, really; we're not buffering */
3267 }
3268
3269 static int con_chars_in_buffer(struct tty_struct *tty)
3270 {
3271         return 0;               /* we're not buffering */
3272 }
3273
3274 /*
3275  * con_throttle and con_unthrottle are only used for
3276  * paste_selection(), which has to stuff in a large number of
3277  * characters...
3278  */
3279 static void con_throttle(struct tty_struct *tty)
3280 {
3281 }
3282
3283 static void con_unthrottle(struct tty_struct *tty)
3284 {
3285         struct vc_data *vc = tty->driver_data;
3286
3287         wake_up_interruptible(&vc->paste_wait);
3288 }
3289
3290 /*
3291  * Turn the Scroll-Lock LED on when the tty is stopped
3292  */
3293 static void con_stop(struct tty_struct *tty)
3294 {
3295         int console_num;
3296         if (!tty)
3297                 return;
3298         console_num = tty->index;
3299         if (!vc_cons_allocated(console_num))
3300                 return;
3301         vt_kbd_con_stop(console_num);
3302 }
3303
3304 /*
3305  * Turn the Scroll-Lock LED off when the console is started
3306  */
3307 static void con_start(struct tty_struct *tty)
3308 {
3309         int console_num;
3310         if (!tty)
3311                 return;
3312         console_num = tty->index;
3313         if (!vc_cons_allocated(console_num))
3314                 return;
3315         vt_kbd_con_start(console_num);
3316 }
3317
3318 static void con_flush_chars(struct tty_struct *tty)
3319 {
3320         struct vc_data *vc;
3321
3322         if (in_interrupt())     /* from flush_to_ldisc */
3323                 return;
3324
3325         /* if we race with con_close(), vt may be null */
3326         console_lock();
3327         vc = tty->driver_data;
3328         if (vc)
3329                 set_cursor(vc);
3330         console_unlock();
3331 }
3332
3333 /*
3334  * Allocate the console screen memory.
3335  */
3336 static int con_install(struct tty_driver *driver, struct tty_struct *tty)
3337 {
3338         unsigned int currcons = tty->index;
3339         struct vc_data *vc;
3340         int ret;
3341
3342         console_lock();
3343         ret = vc_allocate(currcons);
3344         if (ret)
3345                 goto unlock;
3346
3347         vc = vc_cons[currcons].d;
3348
3349         /* Still being freed */
3350         if (vc->port.tty) {
3351                 ret = -ERESTARTSYS;
3352                 goto unlock;
3353         }
3354
3355         ret = tty_port_install(&vc->port, driver, tty);
3356         if (ret)
3357                 goto unlock;
3358
3359         tty->driver_data = vc;
3360         vc->port.tty = tty;
3361         tty_port_get(&vc->port);
3362
3363         if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
3364                 tty->winsize.ws_row = vc_cons[currcons].d->vc_rows;
3365                 tty->winsize.ws_col = vc_cons[currcons].d->vc_cols;
3366         }
3367         if (vc->vc_utf)
3368                 tty->termios.c_iflag |= IUTF8;
3369         else
3370                 tty->termios.c_iflag &= ~IUTF8;
3371 unlock:
3372         console_unlock();
3373         return ret;
3374 }
3375
3376 static int con_open(struct tty_struct *tty, struct file *filp)
3377 {
3378         /* everything done in install */
3379         return 0;
3380 }
3381
3382
3383 static void con_close(struct tty_struct *tty, struct file *filp)
3384 {
3385         /* Nothing to do - we defer to shutdown */
3386 }
3387
3388 static void con_shutdown(struct tty_struct *tty)
3389 {
3390         struct vc_data *vc = tty->driver_data;
3391         BUG_ON(vc == NULL);
3392         console_lock();
3393         vc->port.tty = NULL;
3394         console_unlock();
3395 }
3396
3397 static void con_cleanup(struct tty_struct *tty)
3398 {
3399         struct vc_data *vc = tty->driver_data;
3400
3401         tty_port_put(&vc->port);
3402 }
3403
3404 static int default_color           = 7; /* white */
3405 static int default_italic_color    = 2; // green (ASCII)
3406 static int default_underline_color = 3; // cyan (ASCII)
3407 module_param_named(color, default_color, int, S_IRUGO | S_IWUSR);
3408 module_param_named(italic, default_italic_color, int, S_IRUGO | S_IWUSR);
3409 module_param_named(underline, default_underline_color, int, S_IRUGO | S_IWUSR);
3410
3411 static void vc_init(struct vc_data *vc, unsigned int rows,
3412                     unsigned int cols, int do_clear)
3413 {
3414         int j, k ;
3415
3416         vc->vc_cols = cols;
3417         vc->vc_rows = rows;
3418         vc->vc_size_row = cols << 1;
3419         vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
3420
3421         set_origin(vc);
3422         vc->vc_pos = vc->vc_origin;
3423         reset_vc(vc);
3424         for (j=k=0; j<16; j++) {
3425                 vc->vc_palette[k++] = default_red[j] ;
3426                 vc->vc_palette[k++] = default_grn[j] ;
3427                 vc->vc_palette[k++] = default_blu[j] ;
3428         }
3429         vc->vc_def_color       = default_color;
3430         vc->vc_ulcolor         = default_underline_color;
3431         vc->vc_itcolor         = default_italic_color;
3432         vc->vc_halfcolor       = 0x08;   /* grey */
3433         init_waitqueue_head(&vc->paste_wait);
3434         reset_terminal(vc, do_clear);
3435 }
3436
3437 /*
3438  * This routine initializes console interrupts, and does nothing
3439  * else. If you want the screen to clear, call tty_write with
3440  * the appropriate escape-sequence.
3441  */
3442
3443 static int __init con_init(void)
3444 {
3445         const char *display_desc = NULL;
3446         struct vc_data *vc;
3447         unsigned int currcons = 0, i;
3448
3449         console_lock();
3450
3451         if (!conswitchp)
3452                 conswitchp = &dummy_con;
3453         display_desc = conswitchp->con_startup();
3454         if (!display_desc) {
3455                 fg_console = 0;
3456                 console_unlock();
3457                 return 0;
3458         }
3459
3460         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3461                 struct con_driver *con_driver = &registered_con_driver[i];
3462
3463                 if (con_driver->con == NULL) {
3464                         con_driver->con = conswitchp;
3465                         con_driver->desc = display_desc;
3466                         con_driver->flag = CON_DRIVER_FLAG_INIT;
3467                         con_driver->first = 0;
3468                         con_driver->last = MAX_NR_CONSOLES - 1;
3469                         break;
3470                 }
3471         }
3472
3473         for (i = 0; i < MAX_NR_CONSOLES; i++)
3474                 con_driver_map[i] = conswitchp;
3475
3476         if (blankinterval) {
3477                 blank_state = blank_normal_wait;
3478                 mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3479         }
3480
3481         for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) {
3482                 vc_cons[currcons].d = vc = kzalloc(sizeof(struct vc_data), GFP_NOWAIT);
3483                 INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
3484                 tty_port_init(&vc->port);
3485                 visual_init(vc, currcons, 1);
3486                 /* Assuming vc->vc_{cols,rows,screenbuf_size} are sane here. */
3487                 vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_NOWAIT);
3488                 vc_init(vc, vc->vc_rows, vc->vc_cols,
3489                         currcons || !vc->vc_sw->con_save_screen);
3490         }
3491         currcons = fg_console = 0;
3492         master_display_fg = vc = vc_cons[currcons].d;
3493         set_origin(vc);
3494         save_screen(vc);
3495         gotoxy(vc, vc->state.x, vc->state.y);
3496         csi_J(vc, 0);
3497         update_screen(vc);
3498         pr_info("Console: %s %s %dx%d\n",
3499                 vc->vc_can_do_color ? "colour" : "mono",
3500                 display_desc, vc->vc_cols, vc->vc_rows);
3501         printable = 1;
3502
3503         console_unlock();
3504
3505 #ifdef CONFIG_VT_CONSOLE
3506         register_console(&vt_console_driver);
3507 #endif
3508         return 0;
3509 }
3510 console_initcall(con_init);
3511
3512 static const struct tty_operations con_ops = {
3513         .install = con_install,
3514         .open = con_open,
3515         .close = con_close,
3516         .write = con_write,
3517         .write_room = con_write_room,
3518         .put_char = con_put_char,
3519         .flush_chars = con_flush_chars,
3520         .chars_in_buffer = con_chars_in_buffer,
3521         .ioctl = vt_ioctl,
3522 #ifdef CONFIG_COMPAT
3523         .compat_ioctl = vt_compat_ioctl,
3524 #endif
3525         .stop = con_stop,
3526         .start = con_start,
3527         .throttle = con_throttle,
3528         .unthrottle = con_unthrottle,
3529         .resize = vt_resize,
3530         .shutdown = con_shutdown,
3531         .cleanup = con_cleanup,
3532 };
3533
3534 static struct cdev vc0_cdev;
3535
3536 static ssize_t show_tty_active(struct device *dev,
3537                                 struct device_attribute *attr, char *buf)
3538 {
3539         return sprintf(buf, "tty%d\n", fg_console + 1);
3540 }
3541 static DEVICE_ATTR(active, S_IRUGO, show_tty_active, NULL);
3542
3543 static struct attribute *vt_dev_attrs[] = {
3544         &dev_attr_active.attr,
3545         NULL
3546 };
3547
3548 ATTRIBUTE_GROUPS(vt_dev);
3549
3550 int __init vty_init(const struct file_operations *console_fops)
3551 {
3552         cdev_init(&vc0_cdev, console_fops);
3553         if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
3554             register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
3555                 panic("Couldn't register /dev/tty0 driver\n");
3556         tty0dev = device_create_with_groups(tty_class, NULL,
3557                                             MKDEV(TTY_MAJOR, 0), NULL,
3558                                             vt_dev_groups, "tty0");
3559         if (IS_ERR(tty0dev))
3560                 tty0dev = NULL;
3561
3562         vcs_init();
3563
3564         console_driver = alloc_tty_driver(MAX_NR_CONSOLES);
3565         if (!console_driver)
3566                 panic("Couldn't allocate console driver\n");
3567
3568         console_driver->name = "tty";
3569         console_driver->name_base = 1;
3570         console_driver->major = TTY_MAJOR;
3571         console_driver->minor_start = 1;
3572         console_driver->type = TTY_DRIVER_TYPE_CONSOLE;
3573         console_driver->init_termios = tty_std_termios;
3574         if (default_utf8)
3575                 console_driver->init_termios.c_iflag |= IUTF8;
3576         console_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS;
3577         tty_set_operations(console_driver, &con_ops);
3578         if (tty_register_driver(console_driver))
3579                 panic("Couldn't register console driver\n");
3580         kbd_init();
3581         console_map_init();
3582 #ifdef CONFIG_MDA_CONSOLE
3583         mda_console_init();
3584 #endif
3585         return 0;
3586 }
3587
3588 #ifndef VT_SINGLE_DRIVER
3589
3590 static struct class *vtconsole_class;
3591
3592 static int do_bind_con_driver(const struct consw *csw, int first, int last,
3593                            int deflt)
3594 {
3595         struct module *owner = csw->owner;
3596         const char *desc = NULL;
3597         struct con_driver *con_driver;
3598         int i, j = -1, k = -1, retval = -ENODEV;
3599
3600         if (!try_module_get(owner))
3601                 return -ENODEV;
3602
3603         WARN_CONSOLE_UNLOCKED();
3604
3605         /* check if driver is registered */
3606         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3607                 con_driver = &registered_con_driver[i];
3608
3609                 if (con_driver->con == csw) {
3610                         desc = con_driver->desc;
3611                         retval = 0;
3612                         break;
3613                 }
3614         }
3615
3616         if (retval)
3617                 goto err;
3618
3619         if (!(con_driver->flag & CON_DRIVER_FLAG_INIT)) {
3620                 csw->con_startup();
3621                 con_driver->flag |= CON_DRIVER_FLAG_INIT;
3622         }
3623
3624         if (deflt) {
3625                 if (conswitchp)
3626                         module_put(conswitchp->owner);
3627
3628                 __module_get(owner);
3629                 conswitchp = csw;
3630         }
3631
3632         first = max(first, con_driver->first);
3633         last = min(last, con_driver->last);
3634
3635         for (i = first; i <= last; i++) {
3636                 int old_was_color;
3637                 struct vc_data *vc = vc_cons[i].d;
3638
3639                 if (con_driver_map[i])
3640                         module_put(con_driver_map[i]->owner);
3641                 __module_get(owner);
3642                 con_driver_map[i] = csw;
3643
3644                 if (!vc || !vc->vc_sw)
3645                         continue;
3646
3647                 j = i;
3648
3649                 if (con_is_visible(vc)) {
3650                         k = i;
3651                         save_screen(vc);
3652                 }
3653
3654                 old_was_color = vc->vc_can_do_color;
3655                 vc->vc_sw->con_deinit(vc);
3656                 vc->vc_origin = (unsigned long)vc->vc_screenbuf;
3657                 visual_init(vc, i, 0);
3658                 set_origin(vc);
3659                 update_attr(vc);
3660
3661                 /* If the console changed between mono <-> color, then
3662                  * the attributes in the screenbuf will be wrong.  The
3663                  * following resets all attributes to something sane.
3664                  */
3665                 if (old_was_color != vc->vc_can_do_color)
3666                         clear_buffer_attributes(vc);
3667         }
3668
3669         pr_info("Console: switching ");
3670         if (!deflt)
3671                 pr_cont("consoles %d-%d ", first + 1, last + 1);
3672         if (j >= 0) {
3673                 struct vc_data *vc = vc_cons[j].d;
3674
3675                 pr_cont("to %s %s %dx%d\n",
3676                         vc->vc_can_do_color ? "colour" : "mono",
3677                         desc, vc->vc_cols, vc->vc_rows);
3678
3679                 if (k >= 0) {
3680                         vc = vc_cons[k].d;
3681                         update_screen(vc);
3682                 }
3683         } else {
3684                 pr_cont("to %s\n", desc);
3685         }
3686
3687         retval = 0;
3688 err:
3689         module_put(owner);
3690         return retval;
3691 };
3692
3693
3694 #ifdef CONFIG_VT_HW_CONSOLE_BINDING
3695 int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
3696 {
3697         struct module *owner = csw->owner;
3698         const struct consw *defcsw = NULL;
3699         struct con_driver *con_driver = NULL, *con_back = NULL;
3700         int i, retval = -ENODEV;
3701
3702         if (!try_module_get(owner))
3703                 return -ENODEV;
3704
3705         WARN_CONSOLE_UNLOCKED();
3706
3707         /* check if driver is registered and if it is unbindable */
3708         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3709                 con_driver = &registered_con_driver[i];
3710
3711                 if (con_driver->con == csw &&
3712                     con_driver->flag & CON_DRIVER_FLAG_MODULE) {
3713                         retval = 0;
3714                         break;
3715                 }
3716         }
3717
3718         if (retval)
3719                 goto err;
3720
3721         retval = -ENODEV;
3722
3723         /* check if backup driver exists */
3724         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3725                 con_back = &registered_con_driver[i];
3726
3727                 if (con_back->con && con_back->con != csw) {
3728                         defcsw = con_back->con;
3729                         retval = 0;
3730                         break;
3731                 }
3732         }
3733
3734         if (retval)
3735                 goto err;
3736
3737         if (!con_is_bound(csw))
3738                 goto err;
3739
3740         first = max(first, con_driver->first);
3741         last = min(last, con_driver->last);
3742
3743         for (i = first; i <= last; i++) {
3744                 if (con_driver_map[i] == csw) {
3745                         module_put(csw->owner);
3746                         con_driver_map[i] = NULL;
3747                 }
3748         }
3749
3750         if (!con_is_bound(defcsw)) {
3751                 const struct consw *defconsw = conswitchp;
3752
3753                 defcsw->con_startup();
3754                 con_back->flag |= CON_DRIVER_FLAG_INIT;
3755                 /*
3756                  * vgacon may change the default driver to point
3757                  * to dummycon, we restore it here...
3758                  */
3759                 conswitchp = defconsw;
3760         }
3761
3762         if (!con_is_bound(csw))
3763                 con_driver->flag &= ~CON_DRIVER_FLAG_INIT;
3764
3765         /* ignore return value, binding should not fail */
3766         do_bind_con_driver(defcsw, first, last, deflt);
3767 err:
3768         module_put(owner);
3769         return retval;
3770
3771 }
3772 EXPORT_SYMBOL_GPL(do_unbind_con_driver);
3773
3774 static int vt_bind(struct con_driver *con)
3775 {
3776         const struct consw *defcsw = NULL, *csw = NULL;
3777         int i, more = 1, first = -1, last = -1, deflt = 0;
3778
3779         if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3780                 goto err;
3781
3782         csw = con->con;
3783
3784         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3785                 struct con_driver *con = &registered_con_driver[i];
3786
3787                 if (con->con && !(con->flag & CON_DRIVER_FLAG_MODULE)) {
3788                         defcsw = con->con;
3789                         break;
3790                 }
3791         }
3792
3793         if (!defcsw)
3794                 goto err;
3795
3796         while (more) {
3797                 more = 0;
3798
3799                 for (i = con->first; i <= con->last; i++) {
3800                         if (con_driver_map[i] == defcsw) {
3801                                 if (first == -1)
3802                                         first = i;
3803                                 last = i;
3804                                 more = 1;
3805                         } else if (first != -1)
3806                                 break;
3807                 }
3808
3809                 if (first == 0 && last == MAX_NR_CONSOLES -1)
3810                         deflt = 1;
3811
3812                 if (first != -1)
3813                         do_bind_con_driver(csw, first, last, deflt);
3814
3815                 first = -1;
3816                 last = -1;
3817                 deflt = 0;
3818         }
3819
3820 err:
3821         return 0;
3822 }
3823
3824 static int vt_unbind(struct con_driver *con)
3825 {
3826         const struct consw *csw = NULL;
3827         int i, more = 1, first = -1, last = -1, deflt = 0;
3828         int ret;
3829
3830         if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3831                 goto err;
3832
3833         csw = con->con;
3834
3835         while (more) {
3836                 more = 0;
3837
3838                 for (i = con->first; i <= con->last; i++) {
3839                         if (con_driver_map[i] == csw) {
3840                                 if (first == -1)
3841                                         first = i;
3842                                 last = i;
3843                                 more = 1;
3844                         } else if (first != -1)
3845                                 break;
3846                 }
3847
3848                 if (first == 0 && last == MAX_NR_CONSOLES -1)
3849                         deflt = 1;
3850
3851                 if (first != -1) {
3852                         ret = do_unbind_con_driver(csw, first, last, deflt);
3853                         if (ret != 0)
3854                                 return ret;
3855                 }
3856
3857                 first = -1;
3858                 last = -1;
3859                 deflt = 0;
3860         }
3861
3862 err:
3863         return 0;
3864 }
3865 #else
3866 static inline int vt_bind(struct con_driver *con)
3867 {
3868         return 0;
3869 }
3870 static inline int vt_unbind(struct con_driver *con)
3871 {
3872         return 0;
3873 }
3874 #endif /* CONFIG_VT_HW_CONSOLE_BINDING */
3875
3876 static ssize_t store_bind(struct device *dev, struct device_attribute *attr,
3877                           const char *buf, size_t count)
3878 {
3879         struct con_driver *con = dev_get_drvdata(dev);
3880         int bind = simple_strtoul(buf, NULL, 0);
3881
3882         console_lock();
3883
3884         if (bind)
3885                 vt_bind(con);
3886         else
3887                 vt_unbind(con);
3888
3889         console_unlock();
3890
3891         return count;
3892 }
3893
3894 static ssize_t show_bind(struct device *dev, struct device_attribute *attr,
3895                          char *buf)
3896 {
3897         struct con_driver *con = dev_get_drvdata(dev);
3898         int bind;
3899
3900         console_lock();
3901         bind = con_is_bound(con->con);
3902         console_unlock();
3903
3904         return snprintf(buf, PAGE_SIZE, "%i\n", bind);
3905 }
3906
3907 static ssize_t show_name(struct device *dev, struct device_attribute *attr,
3908                          char *buf)
3909 {
3910         struct con_driver *con = dev_get_drvdata(dev);
3911
3912         return snprintf(buf, PAGE_SIZE, "%s %s\n",
3913                         (con->flag & CON_DRIVER_FLAG_MODULE) ? "(M)" : "(S)",
3914                          con->desc);
3915
3916 }
3917
3918 static DEVICE_ATTR(bind, S_IRUGO|S_IWUSR, show_bind, store_bind);
3919 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
3920
3921 static struct attribute *con_dev_attrs[] = {
3922         &dev_attr_bind.attr,
3923         &dev_attr_name.attr,
3924         NULL
3925 };
3926
3927 ATTRIBUTE_GROUPS(con_dev);
3928
3929 static int vtconsole_init_device(struct con_driver *con)
3930 {
3931         con->flag |= CON_DRIVER_FLAG_ATTR;
3932         return 0;
3933 }
3934
3935 static void vtconsole_deinit_device(struct con_driver *con)
3936 {
3937         con->flag &= ~CON_DRIVER_FLAG_ATTR;
3938 }
3939
3940 /**
3941  * con_is_bound - checks if driver is bound to the console
3942  * @csw: console driver
3943  *
3944  * RETURNS: zero if unbound, nonzero if bound
3945  *
3946  * Drivers can call this and if zero, they should release
3947  * all resources allocated on con_startup()
3948  */
3949 int con_is_bound(const struct consw *csw)
3950 {
3951         int i, bound = 0;
3952
3953         WARN_CONSOLE_UNLOCKED();
3954
3955         for (i = 0; i < MAX_NR_CONSOLES; i++) {
3956                 if (con_driver_map[i] == csw) {
3957                         bound = 1;
3958                         break;
3959                 }
3960         }
3961
3962         return bound;
3963 }
3964 EXPORT_SYMBOL(con_is_bound);
3965
3966 /**
3967  * con_is_visible - checks whether the current console is visible
3968  * @vc: virtual console
3969  *
3970  * RETURNS: zero if not visible, nonzero if visible
3971  */
3972 bool con_is_visible(const struct vc_data *vc)
3973 {
3974         WARN_CONSOLE_UNLOCKED();
3975
3976         return *vc->vc_display_fg == vc;
3977 }
3978 EXPORT_SYMBOL(con_is_visible);
3979
3980 /**
3981  * con_debug_enter - prepare the console for the kernel debugger
3982  * @sw: console driver
3983  *
3984  * Called when the console is taken over by the kernel debugger, this
3985  * function needs to save the current console state, then put the console
3986  * into a state suitable for the kernel debugger.
3987  *
3988  * RETURNS:
3989  * Zero on success, nonzero if a failure occurred when trying to prepare
3990  * the console for the debugger.
3991  */
3992 int con_debug_enter(struct vc_data *vc)
3993 {
3994         int ret = 0;
3995
3996         saved_fg_console = fg_console;
3997         saved_last_console = last_console;
3998         saved_want_console = want_console;
3999         saved_vc_mode = vc->vc_mode;
4000         saved_console_blanked = console_blanked;
4001         vc->vc_mode = KD_TEXT;
4002         console_blanked = 0;
4003         if (vc->vc_sw->con_debug_enter)
4004                 ret = vc->vc_sw->con_debug_enter(vc);
4005 #ifdef CONFIG_KGDB_KDB
4006         /* Set the initial LINES variable if it is not already set */
4007         if (vc->vc_rows < 999) {
4008                 int linecount;
4009                 char lns[4];
4010                 const char *setargs[3] = {
4011                         "set",
4012                         "LINES",
4013                         lns,
4014                 };
4015                 if (kdbgetintenv(setargs[0], &linecount)) {
4016                         snprintf(lns, 4, "%i", vc->vc_rows);
4017                         kdb_set(2, setargs);
4018                 }
4019         }
4020         if (vc->vc_cols < 999) {
4021                 int colcount;
4022                 char cols[4];
4023                 const char *setargs[3] = {
4024                         "set",
4025                         "COLUMNS",
4026                         cols,
4027                 };
4028                 if (kdbgetintenv(setargs[0], &colcount)) {
4029                         snprintf(cols, 4, "%i", vc->vc_cols);
4030                         kdb_set(2, setargs);
4031                 }
4032         }
4033 #endif /* CONFIG_KGDB_KDB */
4034         return ret;
4035 }
4036 EXPORT_SYMBOL_GPL(con_debug_enter);
4037
4038 /**
4039  * con_debug_leave - restore console state
4040  * @sw: console driver
4041  *
4042  * Restore the console state to what it was before the kernel debugger
4043  * was invoked.
4044  *
4045  * RETURNS:
4046  * Zero on success, nonzero if a failure occurred when trying to restore
4047  * the console.
4048  */
4049 int con_debug_leave(void)
4050 {
4051         struct vc_data *vc;
4052         int ret = 0;
4053
4054         fg_console = saved_fg_console;
4055         last_console = saved_last_console;
4056         want_console = saved_want_console;
4057         console_blanked = saved_console_blanked;
4058         vc_cons[fg_console].d->vc_mode = saved_vc_mode;
4059
4060         vc = vc_cons[fg_console].d;
4061         if (vc->vc_sw->con_debug_leave)
4062                 ret = vc->vc_sw->con_debug_leave(vc);
4063         return ret;
4064 }
4065 EXPORT_SYMBOL_GPL(con_debug_leave);
4066
4067 static int do_register_con_driver(const struct consw *csw, int first, int last)
4068 {
4069         struct module *owner = csw->owner;
4070         struct con_driver *con_driver;
4071         const char *desc;
4072         int i, retval;
4073
4074         WARN_CONSOLE_UNLOCKED();
4075
4076         if (!try_module_get(owner))
4077                 return -ENODEV;
4078
4079         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4080                 con_driver = &registered_con_driver[i];
4081
4082                 /* already registered */
4083                 if (con_driver->con == csw) {
4084                         retval = -EBUSY;
4085                         goto err;
4086                 }
4087         }
4088
4089         desc = csw->con_startup();
4090         if (!desc) {
4091                 retval = -ENODEV;
4092                 goto err;
4093         }
4094
4095         retval = -EINVAL;
4096
4097         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4098                 con_driver = &registered_con_driver[i];
4099
4100                 if (con_driver->con == NULL &&
4101                     !(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE)) {
4102                         con_driver->con = csw;
4103                         con_driver->desc = desc;
4104                         con_driver->node = i;
4105                         con_driver->flag = CON_DRIVER_FLAG_MODULE |
4106                                            CON_DRIVER_FLAG_INIT;
4107                         con_driver->first = first;
4108                         con_driver->last = last;
4109                         retval = 0;
4110                         break;
4111                 }
4112         }
4113
4114         if (retval)
4115                 goto err;
4116
4117         con_driver->dev =
4118                 device_create_with_groups(vtconsole_class, NULL,
4119                                           MKDEV(0, con_driver->node),
4120                                           con_driver, con_dev_groups,
4121                                           "vtcon%i", con_driver->node);
4122         if (IS_ERR(con_driver->dev)) {
4123                 pr_warn("Unable to create device for %s; errno = %ld\n",
4124                         con_driver->desc, PTR_ERR(con_driver->dev));
4125                 con_driver->dev = NULL;
4126         } else {
4127                 vtconsole_init_device(con_driver);
4128         }
4129
4130 err:
4131         module_put(owner);
4132         return retval;
4133 }
4134
4135
4136 /**
4137  * do_unregister_con_driver - unregister console driver from console layer
4138  * @csw: console driver
4139  *
4140  * DESCRIPTION: All drivers that registers to the console layer must
4141  * call this function upon exit, or if the console driver is in a state
4142  * where it won't be able to handle console services, such as the
4143  * framebuffer console without loaded framebuffer drivers.
4144  *
4145  * The driver must unbind first prior to unregistration.
4146  */
4147 int do_unregister_con_driver(const struct consw *csw)
4148 {
4149         int i;
4150
4151         /* cannot unregister a bound driver */
4152         if (con_is_bound(csw))
4153                 return -EBUSY;
4154
4155         if (csw == conswitchp)
4156                 return -EINVAL;
4157
4158         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4159                 struct con_driver *con_driver = &registered_con_driver[i];
4160
4161                 if (con_driver->con == csw) {
4162                         /*
4163                          * Defer the removal of the sysfs entries since that
4164                          * will acquire the kernfs s_active lock and we can't
4165                          * acquire this lock while holding the console lock:
4166                          * the unbind sysfs entry imposes already the opposite
4167                          * order. Reset con already here to prevent any later
4168                          * lookup to succeed and mark this slot as zombie, so
4169                          * it won't get reused until we complete the removal
4170                          * in the deferred work.
4171                          */
4172                         con_driver->con = NULL;
4173                         con_driver->flag = CON_DRIVER_FLAG_ZOMBIE;
4174                         schedule_work(&con_driver_unregister_work);
4175
4176                         return 0;
4177                 }
4178         }
4179
4180         return -ENODEV;
4181 }
4182 EXPORT_SYMBOL_GPL(do_unregister_con_driver);
4183
4184 static void con_driver_unregister_callback(struct work_struct *ignored)
4185 {
4186         int i;
4187
4188         console_lock();
4189
4190         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4191                 struct con_driver *con_driver = &registered_con_driver[i];
4192
4193                 if (!(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE))
4194                         continue;
4195
4196                 console_unlock();
4197
4198                 vtconsole_deinit_device(con_driver);
4199                 device_destroy(vtconsole_class, MKDEV(0, con_driver->node));
4200
4201                 console_lock();
4202
4203                 if (WARN_ON_ONCE(con_driver->con))
4204                         con_driver->con = NULL;
4205                 con_driver->desc = NULL;
4206                 con_driver->dev = NULL;
4207                 con_driver->node = 0;
4208                 WARN_ON_ONCE(con_driver->flag != CON_DRIVER_FLAG_ZOMBIE);
4209                 con_driver->flag = 0;
4210                 con_driver->first = 0;
4211                 con_driver->last = 0;
4212         }
4213
4214         console_unlock();
4215 }
4216
4217 /*
4218  *      If we support more console drivers, this function is used
4219  *      when a driver wants to take over some existing consoles
4220  *      and become default driver for newly opened ones.
4221  *
4222  *      do_take_over_console is basically a register followed by bind
4223  */
4224 int do_take_over_console(const struct consw *csw, int first, int last, int deflt)
4225 {
4226         int err;
4227
4228         err = do_register_con_driver(csw, first, last);
4229         /*
4230          * If we get an busy error we still want to bind the console driver
4231          * and return success, as we may have unbound the console driver
4232          * but not unregistered it.
4233          */
4234         if (err == -EBUSY)
4235                 err = 0;
4236         if (!err)
4237                 do_bind_con_driver(csw, first, last, deflt);
4238
4239         return err;
4240 }
4241 EXPORT_SYMBOL_GPL(do_take_over_console);
4242
4243
4244 /*
4245  * give_up_console is a wrapper to unregister_con_driver. It will only
4246  * work if driver is fully unbound.
4247  */
4248 void give_up_console(const struct consw *csw)
4249 {
4250         console_lock();
4251         do_unregister_con_driver(csw);
4252         console_unlock();
4253 }
4254
4255 static int __init vtconsole_class_init(void)
4256 {
4257         int i;
4258
4259         vtconsole_class = class_create(THIS_MODULE, "vtconsole");
4260         if (IS_ERR(vtconsole_class)) {
4261                 pr_warn("Unable to create vt console class; errno = %ld\n",
4262                         PTR_ERR(vtconsole_class));
4263                 vtconsole_class = NULL;
4264         }
4265
4266         /* Add system drivers to sysfs */
4267         for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4268                 struct con_driver *con = &registered_con_driver[i];
4269
4270                 if (con->con && !con->dev) {
4271                         con->dev =
4272                                 device_create_with_groups(vtconsole_class, NULL,
4273                                                           MKDEV(0, con->node),
4274                                                           con, con_dev_groups,
4275                                                           "vtcon%i", con->node);
4276
4277                         if (IS_ERR(con->dev)) {
4278                                 pr_warn("Unable to create device for %s; errno = %ld\n",
4279                                         con->desc, PTR_ERR(con->dev));
4280                                 con->dev = NULL;
4281                         } else {
4282                                 vtconsole_init_device(con);
4283                         }
4284                 }
4285         }
4286
4287         return 0;
4288 }
4289 postcore_initcall(vtconsole_class_init);
4290
4291 #endif
4292
4293 /*
4294  *      Screen blanking
4295  */
4296
4297 static int set_vesa_blanking(char __user *p)
4298 {
4299         unsigned int mode;
4300
4301         if (get_user(mode, p + 1))
4302                 return -EFAULT;
4303
4304         vesa_blank_mode = (mode < 4) ? mode : 0;
4305         return 0;
4306 }
4307
4308 void do_blank_screen(int entering_gfx)
4309 {
4310         struct vc_data *vc = vc_cons[fg_console].d;
4311         int i;
4312
4313         might_sleep();
4314
4315         WARN_CONSOLE_UNLOCKED();
4316
4317         if (console_blanked) {
4318                 if (blank_state == blank_vesa_wait) {
4319                         blank_state = blank_off;
4320                         vc->vc_sw->con_blank(vc, vesa_blank_mode + 1, 0);
4321                 }
4322                 return;
4323         }
4324
4325         /* entering graphics mode? */
4326         if (entering_gfx) {
4327                 hide_cursor(vc);
4328                 save_screen(vc);
4329                 vc->vc_sw->con_blank(vc, -1, 1);
4330                 console_blanked = fg_console + 1;
4331                 blank_state = blank_off;
4332                 set_origin(vc);
4333                 return;
4334         }
4335
4336         blank_state = blank_off;
4337
4338         /* don't blank graphics */
4339         if (vc->vc_mode != KD_TEXT) {
4340                 console_blanked = fg_console + 1;
4341                 return;
4342         }
4343
4344         hide_cursor(vc);
4345         del_timer_sync(&console_timer);
4346         blank_timer_expired = 0;
4347
4348         save_screen(vc);
4349         /* In case we need to reset origin, blanking hook returns 1 */
4350         i = vc->vc_sw->con_blank(vc, vesa_off_interval ? 1 : (vesa_blank_mode + 1), 0);
4351         console_blanked = fg_console + 1;
4352         if (i)
4353                 set_origin(vc);
4354
4355         if (console_blank_hook && console_blank_hook(1))
4356                 return;
4357
4358         if (vesa_off_interval && vesa_blank_mode) {
4359                 blank_state = blank_vesa_wait;
4360                 mod_timer(&console_timer, jiffies + vesa_off_interval);
4361         }
4362         vt_event_post(VT_EVENT_BLANK, vc->vc_num, vc->vc_num);
4363 }
4364 EXPORT_SYMBOL(do_blank_screen);
4365
4366 /*
4367  * Called by timer as well as from vt_console_driver
4368  */
4369 void do_unblank_screen(int leaving_gfx)
4370 {
4371         struct vc_data *vc;
4372
4373         /* This should now always be called from a "sane" (read: can schedule)
4374          * context for the sake of the low level drivers, except in the special
4375          * case of oops_in_progress
4376          */
4377         if (!oops_in_progress)
4378                 might_sleep();
4379
4380         WARN_CONSOLE_UNLOCKED();
4381
4382         ignore_poke = 0;
4383         if (!console_blanked)
4384                 return;
4385         if (!vc_cons_allocated(fg_console)) {
4386                 /* impossible */
4387                 pr_warn("unblank_screen: tty %d not allocated ??\n",
4388                         fg_console + 1);
4389                 return;
4390         }
4391         vc = vc_cons[fg_console].d;
4392         if (vc->vc_mode != KD_TEXT)
4393                 return; /* but leave console_blanked != 0 */
4394
4395         if (blankinterval) {
4396                 mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4397                 blank_state = blank_normal_wait;
4398         }
4399
4400         console_blanked = 0;
4401         if (vc->vc_sw->con_blank(vc, 0, leaving_gfx))
4402                 /* Low-level driver cannot restore -> do it ourselves */
4403                 update_screen(vc);
4404         if (console_blank_hook)
4405                 console_blank_hook(0);
4406         set_palette(vc);
4407         set_cursor(vc);
4408         vt_event_post(VT_EVENT_UNBLANK, vc->vc_num, vc->vc_num);
4409 }
4410 EXPORT_SYMBOL(do_unblank_screen);
4411
4412 /*
4413  * This is called by the outside world to cause a forced unblank, mostly for
4414  * oopses. Currently, I just call do_unblank_screen(0), but we could eventually
4415  * call it with 1 as an argument and so force a mode restore... that may kill
4416  * X or at least garbage the screen but would also make the Oops visible...
4417  */
4418 void unblank_screen(void)
4419 {
4420         do_unblank_screen(0);
4421 }
4422
4423 /*
4424  * We defer the timer blanking to work queue so it can take the console mutex
4425  * (console operations can still happen at irq time, but only from printk which
4426  * has the console mutex. Not perfect yet, but better than no locking
4427  */
4428 static void blank_screen_t(struct timer_list *unused)
4429 {
4430         blank_timer_expired = 1;
4431         schedule_work(&console_work);
4432 }
4433
4434 void poke_blanked_console(void)
4435 {
4436         WARN_CONSOLE_UNLOCKED();
4437
4438         /* Add this so we quickly catch whoever might call us in a non
4439          * safe context. Nowadays, unblank_screen() isn't to be called in
4440          * atomic contexts and is allowed to schedule (with the special case
4441          * of oops_in_progress, but that isn't of any concern for this
4442          * function. --BenH.
4443          */
4444         might_sleep();
4445
4446         /* This isn't perfectly race free, but a race here would be mostly harmless,
4447          * at worse, we'll do a spurrious blank and it's unlikely
4448          */
4449         del_timer(&console_timer);
4450         blank_timer_expired = 0;
4451
4452         if (ignore_poke || !vc_cons[fg_console].d || vc_cons[fg_console].d->vc_mode == KD_GRAPHICS)
4453                 return;
4454         if (console_blanked)
4455                 unblank_screen();
4456         else if (blankinterval) {
4457                 mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4458                 blank_state = blank_normal_wait;
4459         }
4460 }
4461
4462 /*
4463  *      Palettes
4464  */
4465
4466 static void set_palette(struct vc_data *vc)
4467 {
4468         WARN_CONSOLE_UNLOCKED();
4469
4470         if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_set_palette)
4471                 vc->vc_sw->con_set_palette(vc, color_table);
4472 }
4473
4474 /*
4475  * Load palette into the DAC registers. arg points to a colour
4476  * map, 3 bytes per colour, 16 colours, range from 0 to 255.
4477  */
4478
4479 int con_set_cmap(unsigned char __user *arg)
4480 {
4481         int i, j, k;
4482         unsigned char colormap[3*16];
4483
4484         if (copy_from_user(colormap, arg, sizeof(colormap)))
4485                 return -EFAULT;
4486
4487         console_lock();
4488         for (i = k = 0; i < 16; i++) {
4489                 default_red[i] = colormap[k++];
4490                 default_grn[i] = colormap[k++];
4491                 default_blu[i] = colormap[k++];
4492         }
4493         for (i = 0; i < MAX_NR_CONSOLES; i++) {
4494                 if (!vc_cons_allocated(i))
4495                         continue;
4496                 for (j = k = 0; j < 16; j++) {
4497                         vc_cons[i].d->vc_palette[k++] = default_red[j];
4498                         vc_cons[i].d->vc_palette[k++] = default_grn[j];
4499                         vc_cons[i].d->vc_palette[k++] = default_blu[j];
4500                 }
4501                 set_palette(vc_cons[i].d);
4502         }
4503         console_unlock();
4504
4505         return 0;
4506 }
4507
4508 int con_get_cmap(unsigned char __user *arg)
4509 {
4510         int i, k;
4511         unsigned char colormap[3*16];
4512
4513         console_lock();
4514         for (i = k = 0; i < 16; i++) {
4515                 colormap[k++] = default_red[i];
4516                 colormap[k++] = default_grn[i];
4517                 colormap[k++] = default_blu[i];
4518         }
4519         console_unlock();
4520
4521         if (copy_to_user(arg, colormap, sizeof(colormap)))
4522                 return -EFAULT;
4523
4524         return 0;
4525 }
4526
4527 void reset_palette(struct vc_data *vc)
4528 {
4529         int j, k;
4530         for (j=k=0; j<16; j++) {
4531                 vc->vc_palette[k++] = default_red[j];
4532                 vc->vc_palette[k++] = default_grn[j];
4533                 vc->vc_palette[k++] = default_blu[j];
4534         }
4535         set_palette(vc);
4536 }
4537
4538 /*
4539  *  Font switching
4540  *
4541  *  Currently we only support fonts up to 32 pixels wide, at a maximum height
4542  *  of 32 pixels. Userspace fontdata is stored with 32 bytes (shorts/ints,
4543  *  depending on width) reserved for each character which is kinda wasty, but
4544  *  this is done in order to maintain compatibility with the EGA/VGA fonts. It
4545  *  is up to the actual low-level console-driver convert data into its favorite
4546  *  format (maybe we should add a `fontoffset' field to the `display'
4547  *  structure so we won't have to convert the fontdata all the time.
4548  *  /Jes
4549  */
4550
4551 #define max_font_size 65536
4552
4553 static int con_font_get(struct vc_data *vc, struct console_font_op *op)
4554 {
4555         struct console_font font;
4556         int rc = -EINVAL;
4557         int c;
4558
4559         if (op->data) {
4560                 font.data = kmalloc(max_font_size, GFP_KERNEL);
4561                 if (!font.data)
4562                         return -ENOMEM;
4563         } else
4564                 font.data = NULL;
4565
4566         console_lock();
4567         if (vc->vc_mode != KD_TEXT)
4568                 rc = -EINVAL;
4569         else if (vc->vc_sw->con_font_get)
4570                 rc = vc->vc_sw->con_font_get(vc, &font);
4571         else
4572                 rc = -ENOSYS;
4573         console_unlock();
4574
4575         if (rc)
4576                 goto out;
4577
4578         c = (font.width+7)/8 * 32 * font.charcount;
4579
4580         if (op->data && font.charcount > op->charcount)
4581                 rc = -ENOSPC;
4582         if (!(op->flags & KD_FONT_FLAG_OLD)) {
4583                 if (font.width > op->width || font.height > op->height)
4584                         rc = -ENOSPC;
4585         } else {
4586                 if (font.width != 8)
4587                         rc = -EIO;
4588                 else if ((op->height && font.height > op->height) ||
4589                          font.height > 32)
4590                         rc = -ENOSPC;
4591         }
4592         if (rc)
4593                 goto out;
4594
4595         op->height = font.height;
4596         op->width = font.width;
4597         op->charcount = font.charcount;
4598
4599         if (op->data && copy_to_user(op->data, font.data, c))
4600                 rc = -EFAULT;
4601
4602 out:
4603         kfree(font.data);
4604         return rc;
4605 }
4606
4607 static int con_font_set(struct vc_data *vc, struct console_font_op *op)
4608 {
4609         struct console_font font;
4610         int rc = -EINVAL;
4611         int size;
4612
4613         if (vc->vc_mode != KD_TEXT)
4614                 return -EINVAL;
4615         if (!op->data)
4616                 return -EINVAL;
4617         if (op->charcount > 512)
4618                 return -EINVAL;
4619         if (op->width <= 0 || op->width > 32 || op->height > 32)
4620                 return -EINVAL;
4621         size = (op->width+7)/8 * 32 * op->charcount;
4622         if (size > max_font_size)
4623                 return -ENOSPC;
4624
4625         font.data = memdup_user(op->data, size);
4626         if (IS_ERR(font.data))
4627                 return PTR_ERR(font.data);
4628
4629         if (!op->height) {              /* Need to guess font height [compat] */
4630                 int h, i;
4631                 u8 *charmap = font.data;
4632
4633                 /*
4634                  * If from KDFONTOP ioctl, don't allow things which can be done
4635                  * in userland,so that we can get rid of this soon
4636                  */
4637                 if (!(op->flags & KD_FONT_FLAG_OLD)) {
4638                         kfree(font.data);
4639                         return -EINVAL;
4640                 }
4641
4642                 for (h = 32; h > 0; h--)
4643                         for (i = 0; i < op->charcount; i++)
4644                                 if (charmap[32*i+h-1])
4645                                         goto nonzero;
4646
4647                 kfree(font.data);
4648                 return -EINVAL;
4649
4650         nonzero:
4651                 op->height = h;
4652         }
4653
4654         font.charcount = op->charcount;
4655         font.width = op->width;
4656         font.height = op->height;
4657
4658         console_lock();
4659         if (vc->vc_mode != KD_TEXT)
4660                 rc = -EINVAL;
4661         else if (vc->vc_sw->con_font_set)
4662                 rc = vc->vc_sw->con_font_set(vc, &font, op->flags);
4663         else
4664                 rc = -ENOSYS;
4665         console_unlock();
4666         kfree(font.data);
4667         return rc;
4668 }
4669
4670 static int con_font_default(struct vc_data *vc, struct console_font_op *op)
4671 {
4672         struct console_font font = {.width = op->width, .height = op->height};
4673         char name[MAX_FONT_NAME];
4674         char *s = name;
4675         int rc;
4676
4677
4678         if (!op->data)
4679                 s = NULL;
4680         else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0)
4681                 return -EFAULT;
4682         else
4683                 name[MAX_FONT_NAME - 1] = 0;
4684
4685         console_lock();
4686         if (vc->vc_mode != KD_TEXT) {
4687                 console_unlock();
4688                 return -EINVAL;
4689         }
4690         if (vc->vc_sw->con_font_default)
4691                 rc = vc->vc_sw->con_font_default(vc, &font, s);
4692         else
4693                 rc = -ENOSYS;
4694         console_unlock();
4695         if (!rc) {
4696                 op->width = font.width;
4697                 op->height = font.height;
4698         }
4699         return rc;
4700 }
4701
4702 static int con_font_copy(struct vc_data *vc, struct console_font_op *op)
4703 {
4704         int con = op->height;
4705         int rc;
4706
4707
4708         console_lock();
4709         if (vc->vc_mode != KD_TEXT)
4710                 rc = -EINVAL;
4711         else if (!vc->vc_sw->con_font_copy)
4712                 rc = -ENOSYS;
4713         else if (con < 0 || !vc_cons_allocated(con))
4714                 rc = -ENOTTY;
4715         else if (con == vc->vc_num)     /* nothing to do */
4716                 rc = 0;
4717         else
4718                 rc = vc->vc_sw->con_font_copy(vc, con);
4719         console_unlock();
4720         return rc;
4721 }
4722
4723 int con_font_op(struct vc_data *vc, struct console_font_op *op)
4724 {
4725         switch (op->op) {
4726         case KD_FONT_OP_SET:
4727                 return con_font_set(vc, op);
4728         case KD_FONT_OP_GET:
4729                 return con_font_get(vc, op);
4730         case KD_FONT_OP_SET_DEFAULT:
4731                 return con_font_default(vc, op);
4732         case KD_FONT_OP_COPY:
4733                 return con_font_copy(vc, op);
4734         }
4735         return -ENOSYS;
4736 }
4737
4738 /*
4739  *      Interface exported to selection and vcs.
4740  */
4741
4742 /* used by selection */
4743 u16 screen_glyph(struct vc_data *vc, int offset)
4744 {
4745         u16 w = scr_readw(screenpos(vc, offset, 1));
4746         u16 c = w & 0xff;
4747
4748         if (w & vc->vc_hi_font_mask)
4749                 c |= 0x100;
4750         return c;
4751 }
4752 EXPORT_SYMBOL_GPL(screen_glyph);
4753
4754 u32 screen_glyph_unicode(struct vc_data *vc, int n)
4755 {
4756         struct uni_screen *uniscr = get_vc_uniscr(vc);
4757
4758         if (uniscr)
4759                 return uniscr->lines[n / vc->vc_cols][n % vc->vc_cols];
4760         return inverse_translate(vc, screen_glyph(vc, n * 2), 1);
4761 }
4762 EXPORT_SYMBOL_GPL(screen_glyph_unicode);
4763
4764 /* used by vcs - note the word offset */
4765 unsigned short *screen_pos(struct vc_data *vc, int w_offset, int viewed)
4766 {
4767         return screenpos(vc, 2 * w_offset, viewed);
4768 }
4769 EXPORT_SYMBOL_GPL(screen_pos);
4770
4771 void getconsxy(struct vc_data *vc, unsigned char *p)
4772 {
4773         /* clamp values if they don't fit */
4774         p[0] = min(vc->state.x, 0xFFu);
4775         p[1] = min(vc->state.y, 0xFFu);
4776 }
4777
4778 void putconsxy(struct vc_data *vc, unsigned char *p)
4779 {
4780         hide_cursor(vc);
4781         gotoxy(vc, p[0], p[1]);
4782         set_cursor(vc);
4783 }
4784
4785 u16 vcs_scr_readw(struct vc_data *vc, const u16 *org)
4786 {
4787         if ((unsigned long)org == vc->vc_pos && softcursor_original != -1)
4788                 return softcursor_original;
4789         return scr_readw(org);
4790 }
4791
4792 void vcs_scr_writew(struct vc_data *vc, u16 val, u16 *org)
4793 {
4794         scr_writew(val, org);
4795         if ((unsigned long)org == vc->vc_pos) {
4796                 softcursor_original = -1;
4797                 add_softcursor(vc);
4798         }
4799 }
4800
4801 void vcs_scr_updated(struct vc_data *vc)
4802 {
4803         notify_update(vc);
4804 }
4805
4806 void vc_scrolldelta_helper(struct vc_data *c, int lines,
4807                 unsigned int rolled_over, void *base, unsigned int size)
4808 {
4809         unsigned long ubase = (unsigned long)base;
4810         ptrdiff_t scr_end = (void *)c->vc_scr_end - base;
4811         ptrdiff_t vorigin = (void *)c->vc_visible_origin - base;
4812         ptrdiff_t origin = (void *)c->vc_origin - base;
4813         int margin = c->vc_size_row * 4;
4814         int from, wrap, from_off, avail;
4815
4816         /* Turn scrollback off */
4817         if (!lines) {
4818                 c->vc_visible_origin = c->vc_origin;
4819                 return;
4820         }
4821
4822         /* Do we have already enough to allow jumping from 0 to the end? */
4823         if (rolled_over > scr_end + margin) {
4824                 from = scr_end;
4825                 wrap = rolled_over + c->vc_size_row;
4826         } else {
4827                 from = 0;
4828                 wrap = size;
4829         }
4830
4831         from_off = (vorigin - from + wrap) % wrap + lines * c->vc_size_row;
4832         avail = (origin - from + wrap) % wrap;
4833
4834         /* Only a little piece would be left? Show all incl. the piece! */
4835         if (avail < 2 * margin)
4836                 margin = 0;
4837         if (from_off < margin)
4838                 from_off = 0;
4839         if (from_off > avail - margin)
4840                 from_off = avail;
4841
4842         c->vc_visible_origin = ubase + (from + from_off) % wrap;
4843 }
4844 EXPORT_SYMBOL_GPL(vc_scrolldelta_helper);
4845
4846 /*
4847  *      Visible symbols for modules
4848  */
4849
4850 EXPORT_SYMBOL(color_table);
4851 EXPORT_SYMBOL(default_red);
4852 EXPORT_SYMBOL(default_grn);
4853 EXPORT_SYMBOL(default_blu);
4854 EXPORT_SYMBOL(update_region);
4855 EXPORT_SYMBOL(redraw_screen);
4856 EXPORT_SYMBOL(vc_resize);
4857 EXPORT_SYMBOL(fg_console);
4858 EXPORT_SYMBOL(console_blank_hook);
4859 EXPORT_SYMBOL(console_blanked);
4860 EXPORT_SYMBOL(vc_cons);
4861 EXPORT_SYMBOL(global_cursor_default);
4862 #ifndef VT_SINGLE_DRIVER
4863 EXPORT_SYMBOL(give_up_console);
4864 #endif