xref: /linux/drivers/tty/vt/vt.c (revision 63307d015b91e626c97bb82e88054af3d0b74643)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Copyright (C) 1991, 1992  Linus Torvalds
4  */
5 
6 /*
7  * Hopefully this will be a rather complete VT102 implementation.
8  *
9  * Beeping thanks to John T Kohl.
10  *
11  * Virtual Consoles, Screen Blanking, Screen Dumping, Color, Graphics
12  *   Chars, and VT100 enhancements by Peter MacDonald.
13  *
14  * Copy and paste function by Andrew Haylett,
15  *   some enhancements by Alessandro Rubini.
16  *
17  * Code to check for different video-cards mostly by Galen Hunt,
18  * <g-hunt@ee.utah.edu>
19  *
20  * Rudimentary ISO 10646/Unicode/UTF-8 character set support by
21  * Markus Kuhn, <mskuhn@immd4.informatik.uni-erlangen.de>.
22  *
23  * Dynamic allocation of consoles, aeb@cwi.nl, May 1994
24  * Resizing of consoles, aeb, 940926
25  *
26  * Code for xterm like mouse click reporting by Peter Orbaek 20-Jul-94
27  * <poe@daimi.aau.dk>
28  *
29  * User-defined bell sound, new setterm control sequences and printk
30  * redirection by Martin Mares <mj@k332.feld.cvut.cz> 19-Nov-95
31  *
32  * APM screenblank bug fixed Takashi Manabe <manabe@roy.dsl.tutics.tut.jp>
33  *
34  * Merge with the abstract console driver by Geert Uytterhoeven
35  * <geert@linux-m68k.org>, Jan 1997.
36  *
37  *   Original m68k console driver modifications by
38  *
39  *     - Arno Griffioen <arno@usn.nl>
40  *     - David Carter <carter@cs.bris.ac.uk>
41  *
42  *   The abstract console driver provides a generic interface for a text
43  *   console. It supports VGA text mode, frame buffer based graphical consoles
44  *   and special graphics processors that are only accessible through some
45  *   registers (e.g. a TMS340x0 GSP).
46  *
47  *   The interface to the hardware is specified using a special structure
48  *   (struct consw) which contains function pointers to console operations
49  *   (see <linux/console.h> for more information).
50  *
51  * Support for changeable cursor shape
52  * by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz>, August 1997
53  *
54  * Ported to i386 and con_scrolldelta fixed
55  * by Emmanuel Marty <core@ggi-project.org>, April 1998
56  *
57  * Resurrected character buffers in videoram plus lots of other trickery
58  * by Martin Mares <mj@atrey.karlin.mff.cuni.cz>, July 1998
59  *
60  * Removed old-style timers, introduced console_timer, made timer
61  * deletion SMP-safe.  17Jun00, Andrew Morton
62  *
63  * Removed console_lock, enabled interrupts across all console operations
64  * 13 March 2001, Andrew Morton
65  *
66  * Fixed UTF-8 mode so alternate charset modes always work according
67  * to control sequences interpreted in do_con_trol function
68  * preserving backward VT100 semigraphics compatibility,
69  * malformed UTF sequences represented as sequences of replacement glyphs,
70  * original codes or '?' as a last resort if replacement glyph is undefined
71  * by Adam Tla/lka <atlka@pg.gda.pl>, Aug 2006
72  */
73 
74 #include <linux/module.h>
75 #include <linux/types.h>
76 #include <linux/sched/signal.h>
77 #include <linux/tty.h>
78 #include <linux/tty_flip.h>
79 #include <linux/kernel.h>
80 #include <linux/string.h>
81 #include <linux/errno.h>
82 #include <linux/kd.h>
83 #include <linux/slab.h>
84 #include <linux/major.h>
85 #include <linux/mm.h>
86 #include <linux/console.h>
87 #include <linux/init.h>
88 #include <linux/mutex.h>
89 #include <linux/vt_kern.h>
90 #include <linux/selection.h>
91 #include <linux/tiocl.h>
92 #include <linux/kbd_kern.h>
93 #include <linux/consolemap.h>
94 #include <linux/timer.h>
95 #include <linux/interrupt.h>
96 #include <linux/workqueue.h>
97 #include <linux/pm.h>
98 #include <linux/font.h>
99 #include <linux/bitops.h>
100 #include <linux/notifier.h>
101 #include <linux/device.h>
102 #include <linux/io.h>
103 #include <linux/uaccess.h>
104 #include <linux/kdb.h>
105 #include <linux/ctype.h>
106 #include <linux/bsearch.h>
107 #include <linux/gcd.h>
108 
109 #define MAX_NR_CON_DRIVER 16
110 
111 #define CON_DRIVER_FLAG_MODULE 1
112 #define CON_DRIVER_FLAG_INIT   2
113 #define CON_DRIVER_FLAG_ATTR   4
114 #define CON_DRIVER_FLAG_ZOMBIE 8
115 
116 struct con_driver {
117 	const struct consw *con;
118 	const char *desc;
119 	struct device *dev;
120 	int node;
121 	int first;
122 	int last;
123 	int flag;
124 };
125 
126 static struct con_driver registered_con_driver[MAX_NR_CON_DRIVER];
127 const struct consw *conswitchp;
128 
129 /* A bitmap for codes <32. A bit of 1 indicates that the code
130  * corresponding to that bit number invokes some special action
131  * (such as cursor movement) and should not be displayed as a
132  * glyph unless the disp_ctrl mode is explicitly enabled.
133  */
134 #define CTRL_ACTION 0x0d00ff81
135 #define CTRL_ALWAYS 0x0800f501	/* Cannot be overridden by disp_ctrl */
136 
137 /*
138  * Here is the default bell parameters: 750HZ, 1/8th of a second
139  */
140 #define DEFAULT_BELL_PITCH	750
141 #define DEFAULT_BELL_DURATION	(HZ/8)
142 #define DEFAULT_CURSOR_BLINK_MS	200
143 
144 struct vc vc_cons [MAX_NR_CONSOLES];
145 
146 #ifndef VT_SINGLE_DRIVER
147 static const struct consw *con_driver_map[MAX_NR_CONSOLES];
148 #endif
149 
150 static int con_open(struct tty_struct *, struct file *);
151 static void vc_init(struct vc_data *vc, unsigned int rows,
152 		    unsigned int cols, int do_clear);
153 static void gotoxy(struct vc_data *vc, int new_x, int new_y);
154 static void save_cur(struct vc_data *vc);
155 static void reset_terminal(struct vc_data *vc, int do_clear);
156 static void con_flush_chars(struct tty_struct *tty);
157 static int set_vesa_blanking(char __user *p);
158 static void set_cursor(struct vc_data *vc);
159 static void hide_cursor(struct vc_data *vc);
160 static void console_callback(struct work_struct *ignored);
161 static void con_driver_unregister_callback(struct work_struct *ignored);
162 static void blank_screen_t(struct timer_list *unused);
163 static void set_palette(struct vc_data *vc);
164 
165 #define vt_get_kmsg_redirect() vt_kmsg_redirect(-1)
166 
167 static int printable;		/* Is console ready for printing? */
168 int default_utf8 = true;
169 module_param(default_utf8, int, S_IRUGO | S_IWUSR);
170 int global_cursor_default = -1;
171 module_param(global_cursor_default, int, S_IRUGO | S_IWUSR);
172 
173 static int cur_default = CUR_DEFAULT;
174 module_param(cur_default, int, S_IRUGO | S_IWUSR);
175 
176 /*
177  * ignore_poke: don't unblank the screen when things are typed.  This is
178  * mainly for the privacy of braille terminal users.
179  */
180 static int ignore_poke;
181 
182 int do_poke_blanked_console;
183 int console_blanked;
184 
185 static int vesa_blank_mode; /* 0:none 1:suspendV 2:suspendH 3:powerdown */
186 static int vesa_off_interval;
187 static int blankinterval;
188 core_param(consoleblank, blankinterval, int, 0444);
189 
190 static DECLARE_WORK(console_work, console_callback);
191 static DECLARE_WORK(con_driver_unregister_work, con_driver_unregister_callback);
192 
193 /*
194  * fg_console is the current virtual console,
195  * last_console is the last used one,
196  * want_console is the console we want to switch to,
197  * saved_* variants are for save/restore around kernel debugger enter/leave
198  */
199 int fg_console;
200 int last_console;
201 int want_console = -1;
202 static int saved_fg_console;
203 static int saved_last_console;
204 static int saved_want_console;
205 static int saved_vc_mode;
206 static int saved_console_blanked;
207 
208 /*
209  * For each existing display, we have a pointer to console currently visible
210  * on that display, allowing consoles other than fg_console to be refreshed
211  * appropriately. Unless the low-level driver supplies its own display_fg
212  * variable, we use this one for the "master display".
213  */
214 static struct vc_data *master_display_fg;
215 
216 /*
217  * Unfortunately, we need to delay tty echo when we're currently writing to the
218  * console since the code is (and always was) not re-entrant, so we schedule
219  * all flip requests to process context with schedule-task() and run it from
220  * console_callback().
221  */
222 
223 /*
224  * For the same reason, we defer scrollback to the console callback.
225  */
226 static int scrollback_delta;
227 
228 /*
229  * Hook so that the power management routines can (un)blank
230  * the console on our behalf.
231  */
232 int (*console_blank_hook)(int);
233 
234 static DEFINE_TIMER(console_timer, blank_screen_t);
235 static int blank_state;
236 static int blank_timer_expired;
237 enum {
238 	blank_off = 0,
239 	blank_normal_wait,
240 	blank_vesa_wait,
241 };
242 
243 /*
244  * /sys/class/tty/tty0/
245  *
246  * the attribute 'active' contains the name of the current vc
247  * console and it supports poll() to detect vc switches
248  */
249 static struct device *tty0dev;
250 
251 /*
252  * Notifier list for console events.
253  */
254 static ATOMIC_NOTIFIER_HEAD(vt_notifier_list);
255 
256 int register_vt_notifier(struct notifier_block *nb)
257 {
258 	return atomic_notifier_chain_register(&vt_notifier_list, nb);
259 }
260 EXPORT_SYMBOL_GPL(register_vt_notifier);
261 
262 int unregister_vt_notifier(struct notifier_block *nb)
263 {
264 	return atomic_notifier_chain_unregister(&vt_notifier_list, nb);
265 }
266 EXPORT_SYMBOL_GPL(unregister_vt_notifier);
267 
268 static void notify_write(struct vc_data *vc, unsigned int unicode)
269 {
270 	struct vt_notifier_param param = { .vc = vc, .c = unicode };
271 	atomic_notifier_call_chain(&vt_notifier_list, VT_WRITE, &param);
272 }
273 
274 static void notify_update(struct vc_data *vc)
275 {
276 	struct vt_notifier_param param = { .vc = vc };
277 	atomic_notifier_call_chain(&vt_notifier_list, VT_UPDATE, &param);
278 }
279 /*
280  *	Low-Level Functions
281  */
282 
283 static inline bool con_is_fg(const struct vc_data *vc)
284 {
285 	return vc->vc_num == fg_console;
286 }
287 
288 static inline bool con_should_update(const struct vc_data *vc)
289 {
290 	return con_is_visible(vc) && !console_blanked;
291 }
292 
293 static inline unsigned short *screenpos(struct vc_data *vc, int offset, int viewed)
294 {
295 	unsigned short *p;
296 
297 	if (!viewed)
298 		p = (unsigned short *)(vc->vc_origin + offset);
299 	else if (!vc->vc_sw->con_screen_pos)
300 		p = (unsigned short *)(vc->vc_visible_origin + offset);
301 	else
302 		p = vc->vc_sw->con_screen_pos(vc, offset);
303 	return p;
304 }
305 
306 /* Called  from the keyboard irq path.. */
307 static inline void scrolldelta(int lines)
308 {
309 	/* FIXME */
310 	/* scrolldelta needs some kind of consistency lock, but the BKL was
311 	   and still is not protecting versus the scheduled back end */
312 	scrollback_delta += lines;
313 	schedule_console_callback();
314 }
315 
316 void schedule_console_callback(void)
317 {
318 	schedule_work(&console_work);
319 }
320 
321 /*
322  * Code to manage unicode-based screen buffers
323  */
324 
325 #ifdef NO_VC_UNI_SCREEN
326 /* this disables and optimizes related code away at compile time */
327 #define get_vc_uniscr(vc) NULL
328 #else
329 #define get_vc_uniscr(vc) vc->vc_uni_screen
330 #endif
331 
332 #define VC_UNI_SCREEN_DEBUG 0
333 
334 typedef uint32_t char32_t;
335 
336 /*
337  * Our screen buffer is preceded by an array of line pointers so that
338  * scrolling only implies some pointer shuffling.
339  */
340 struct uni_screen {
341 	char32_t *lines[0];
342 };
343 
344 static struct uni_screen *vc_uniscr_alloc(unsigned int cols, unsigned int rows)
345 {
346 	struct uni_screen *uniscr;
347 	void *p;
348 	unsigned int memsize, i;
349 
350 	/* allocate everything in one go */
351 	memsize = cols * rows * sizeof(char32_t);
352 	memsize += rows * sizeof(char32_t *);
353 	p = kmalloc(memsize, GFP_KERNEL);
354 	if (!p)
355 		return NULL;
356 
357 	/* initial line pointers */
358 	uniscr = p;
359 	p = uniscr->lines + rows;
360 	for (i = 0; i < rows; i++) {
361 		uniscr->lines[i] = p;
362 		p += cols * sizeof(char32_t);
363 	}
364 	return uniscr;
365 }
366 
367 static void vc_uniscr_set(struct vc_data *vc, struct uni_screen *new_uniscr)
368 {
369 	kfree(vc->vc_uni_screen);
370 	vc->vc_uni_screen = new_uniscr;
371 }
372 
373 static void vc_uniscr_putc(struct vc_data *vc, char32_t uc)
374 {
375 	struct uni_screen *uniscr = get_vc_uniscr(vc);
376 
377 	if (uniscr)
378 		uniscr->lines[vc->vc_y][vc->vc_x] = uc;
379 }
380 
381 static void vc_uniscr_insert(struct vc_data *vc, unsigned int nr)
382 {
383 	struct uni_screen *uniscr = get_vc_uniscr(vc);
384 
385 	if (uniscr) {
386 		char32_t *ln = uniscr->lines[vc->vc_y];
387 		unsigned int x = vc->vc_x, cols = vc->vc_cols;
388 
389 		memmove(&ln[x + nr], &ln[x], (cols - x - nr) * sizeof(*ln));
390 		memset32(&ln[x], ' ', nr);
391 	}
392 }
393 
394 static void vc_uniscr_delete(struct vc_data *vc, unsigned int nr)
395 {
396 	struct uni_screen *uniscr = get_vc_uniscr(vc);
397 
398 	if (uniscr) {
399 		char32_t *ln = uniscr->lines[vc->vc_y];
400 		unsigned int x = vc->vc_x, cols = vc->vc_cols;
401 
402 		memcpy(&ln[x], &ln[x + nr], (cols - x - nr) * sizeof(*ln));
403 		memset32(&ln[cols - nr], ' ', nr);
404 	}
405 }
406 
407 static void vc_uniscr_clear_line(struct vc_data *vc, unsigned int x,
408 				 unsigned int nr)
409 {
410 	struct uni_screen *uniscr = get_vc_uniscr(vc);
411 
412 	if (uniscr) {
413 		char32_t *ln = uniscr->lines[vc->vc_y];
414 
415 		memset32(&ln[x], ' ', nr);
416 	}
417 }
418 
419 static void vc_uniscr_clear_lines(struct vc_data *vc, unsigned int y,
420 				  unsigned int nr)
421 {
422 	struct uni_screen *uniscr = get_vc_uniscr(vc);
423 
424 	if (uniscr) {
425 		unsigned int cols = vc->vc_cols;
426 
427 		while (nr--)
428 			memset32(uniscr->lines[y++], ' ', cols);
429 	}
430 }
431 
432 static void vc_uniscr_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
433 			     enum con_scroll dir, unsigned int nr)
434 {
435 	struct uni_screen *uniscr = get_vc_uniscr(vc);
436 
437 	if (uniscr) {
438 		unsigned int i, j, k, sz, d, clear;
439 
440 		sz = b - t;
441 		clear = b - nr;
442 		d = nr;
443 		if (dir == SM_DOWN) {
444 			clear = t;
445 			d = sz - nr;
446 		}
447 		for (i = 0; i < gcd(d, sz); i++) {
448 			char32_t *tmp = uniscr->lines[t + i];
449 			j = i;
450 			while (1) {
451 				k = j + d;
452 				if (k >= sz)
453 					k -= sz;
454 				if (k == i)
455 					break;
456 				uniscr->lines[t + j] = uniscr->lines[t + k];
457 				j = k;
458 			}
459 			uniscr->lines[t + j] = tmp;
460 		}
461 		vc_uniscr_clear_lines(vc, clear, nr);
462 	}
463 }
464 
465 static void vc_uniscr_copy_area(struct uni_screen *dst,
466 				unsigned int dst_cols,
467 				unsigned int dst_rows,
468 				struct uni_screen *src,
469 				unsigned int src_cols,
470 				unsigned int src_top_row,
471 				unsigned int src_bot_row)
472 {
473 	unsigned int dst_row = 0;
474 
475 	if (!dst)
476 		return;
477 
478 	while (src_top_row < src_bot_row) {
479 		char32_t *src_line = src->lines[src_top_row];
480 		char32_t *dst_line = dst->lines[dst_row];
481 
482 		memcpy(dst_line, src_line, src_cols * sizeof(char32_t));
483 		if (dst_cols - src_cols)
484 			memset32(dst_line + src_cols, ' ', dst_cols - src_cols);
485 		src_top_row++;
486 		dst_row++;
487 	}
488 	while (dst_row < dst_rows) {
489 		char32_t *dst_line = dst->lines[dst_row];
490 
491 		memset32(dst_line, ' ', dst_cols);
492 		dst_row++;
493 	}
494 }
495 
496 /*
497  * Called from vcs_read() to make sure unicode screen retrieval is possible.
498  * This will initialize the unicode screen buffer if not already done.
499  * This returns 0 if OK, or a negative error code otherwise.
500  * In particular, -ENODATA is returned if the console is not in UTF-8 mode.
501  */
502 int vc_uniscr_check(struct vc_data *vc)
503 {
504 	struct uni_screen *uniscr;
505 	unsigned short *p;
506 	int x, y, mask;
507 
508 	if (__is_defined(NO_VC_UNI_SCREEN))
509 		return -EOPNOTSUPP;
510 
511 	WARN_CONSOLE_UNLOCKED();
512 
513 	if (!vc->vc_utf)
514 		return -ENODATA;
515 
516 	if (vc->vc_uni_screen)
517 		return 0;
518 
519 	uniscr = vc_uniscr_alloc(vc->vc_cols, vc->vc_rows);
520 	if (!uniscr)
521 		return -ENOMEM;
522 
523 	/*
524 	 * Let's populate it initially with (imperfect) reverse translation.
525 	 * This is the next best thing we can do short of having it enabled
526 	 * from the start even when no users rely on this functionality. True
527 	 * unicode content will be available after a complete screen refresh.
528 	 */
529 	p = (unsigned short *)vc->vc_origin;
530 	mask = vc->vc_hi_font_mask | 0xff;
531 	for (y = 0; y < vc->vc_rows; y++) {
532 		char32_t *line = uniscr->lines[y];
533 		for (x = 0; x < vc->vc_cols; x++) {
534 			u16 glyph = scr_readw(p++) & mask;
535 			line[x] = inverse_translate(vc, glyph, true);
536 		}
537 	}
538 
539 	vc->vc_uni_screen = uniscr;
540 	return 0;
541 }
542 
543 /*
544  * Called from vcs_read() to get the unicode data from the screen.
545  * This must be preceded by a successful call to vc_uniscr_check() once
546  * the console lock has been taken.
547  */
548 void vc_uniscr_copy_line(struct vc_data *vc, void *dest, int viewed,
549 			 unsigned int row, unsigned int col, unsigned int nr)
550 {
551 	struct uni_screen *uniscr = get_vc_uniscr(vc);
552 	int offset = row * vc->vc_size_row + col * 2;
553 	unsigned long pos;
554 
555 	BUG_ON(!uniscr);
556 
557 	pos = (unsigned long)screenpos(vc, offset, viewed);
558 	if (pos >= vc->vc_origin && pos < vc->vc_scr_end) {
559 		/*
560 		 * Desired position falls in the main screen buffer.
561 		 * However the actual row/col might be different if
562 		 * scrollback is active.
563 		 */
564 		row = (pos - vc->vc_origin) / vc->vc_size_row;
565 		col = ((pos - vc->vc_origin) % vc->vc_size_row) / 2;
566 		memcpy(dest, &uniscr->lines[row][col], nr * sizeof(char32_t));
567 	} else {
568 		/*
569 		 * Scrollback is active. For now let's simply backtranslate
570 		 * the screen glyphs until the unicode screen buffer does
571 		 * synchronize with console display drivers for a scrollback
572 		 * buffer of its own.
573 		 */
574 		u16 *p = (u16 *)pos;
575 		int mask = vc->vc_hi_font_mask | 0xff;
576 		char32_t *uni_buf = dest;
577 		while (nr--) {
578 			u16 glyph = scr_readw(p++) & mask;
579 			*uni_buf++ = inverse_translate(vc, glyph, true);
580 		}
581 	}
582 }
583 
584 /* this is for validation and debugging only */
585 static void vc_uniscr_debug_check(struct vc_data *vc)
586 {
587 	struct uni_screen *uniscr = get_vc_uniscr(vc);
588 	unsigned short *p;
589 	int x, y, mask;
590 
591 	if (!VC_UNI_SCREEN_DEBUG || !uniscr)
592 		return;
593 
594 	WARN_CONSOLE_UNLOCKED();
595 
596 	/*
597 	 * Make sure our unicode screen translates into the same glyphs
598 	 * as the actual screen. This is brutal indeed.
599 	 */
600 	p = (unsigned short *)vc->vc_origin;
601 	mask = vc->vc_hi_font_mask | 0xff;
602 	for (y = 0; y < vc->vc_rows; y++) {
603 		char32_t *line = uniscr->lines[y];
604 		for (x = 0; x < vc->vc_cols; x++) {
605 			u16 glyph = scr_readw(p++) & mask;
606 			char32_t uc = line[x];
607 			int tc = conv_uni_to_pc(vc, uc);
608 			if (tc == -4)
609 				tc = conv_uni_to_pc(vc, 0xfffd);
610 			if (tc == -4)
611 				tc = conv_uni_to_pc(vc, '?');
612 			if (tc != glyph)
613 				pr_err_ratelimited(
614 					"%s: mismatch at %d,%d: glyph=%#x tc=%#x\n",
615 					__func__, x, y, glyph, tc);
616 		}
617 	}
618 }
619 
620 
621 static void con_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
622 		enum con_scroll dir, unsigned int nr)
623 {
624 	u16 *clear, *d, *s;
625 
626 	if (t + nr >= b)
627 		nr = b - t - 1;
628 	if (b > vc->vc_rows || t >= b || nr < 1)
629 		return;
630 	vc_uniscr_scroll(vc, t, b, dir, nr);
631 	if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, t, b, dir, nr))
632 		return;
633 
634 	s = clear = (u16 *)(vc->vc_origin + vc->vc_size_row * t);
635 	d = (u16 *)(vc->vc_origin + vc->vc_size_row * (t + nr));
636 
637 	if (dir == SM_UP) {
638 		clear = s + (b - t - nr) * vc->vc_cols;
639 		swap(s, d);
640 	}
641 	scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
642 	scr_memsetw(clear, vc->vc_video_erase_char, vc->vc_size_row * nr);
643 }
644 
645 static void do_update_region(struct vc_data *vc, unsigned long start, int count)
646 {
647 	unsigned int xx, yy, offset;
648 	u16 *p;
649 
650 	p = (u16 *) start;
651 	if (!vc->vc_sw->con_getxy) {
652 		offset = (start - vc->vc_origin) / 2;
653 		xx = offset % vc->vc_cols;
654 		yy = offset / vc->vc_cols;
655 	} else {
656 		int nxx, nyy;
657 		start = vc->vc_sw->con_getxy(vc, start, &nxx, &nyy);
658 		xx = nxx; yy = nyy;
659 	}
660 	for(;;) {
661 		u16 attrib = scr_readw(p) & 0xff00;
662 		int startx = xx;
663 		u16 *q = p;
664 		while (xx < vc->vc_cols && count) {
665 			if (attrib != (scr_readw(p) & 0xff00)) {
666 				if (p > q)
667 					vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
668 				startx = xx;
669 				q = p;
670 				attrib = scr_readw(p) & 0xff00;
671 			}
672 			p++;
673 			xx++;
674 			count--;
675 		}
676 		if (p > q)
677 			vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
678 		if (!count)
679 			break;
680 		xx = 0;
681 		yy++;
682 		if (vc->vc_sw->con_getxy) {
683 			p = (u16 *)start;
684 			start = vc->vc_sw->con_getxy(vc, start, NULL, NULL);
685 		}
686 	}
687 }
688 
689 void update_region(struct vc_data *vc, unsigned long start, int count)
690 {
691 	WARN_CONSOLE_UNLOCKED();
692 
693 	if (con_should_update(vc)) {
694 		hide_cursor(vc);
695 		do_update_region(vc, start, count);
696 		set_cursor(vc);
697 	}
698 }
699 
700 /* Structure of attributes is hardware-dependent */
701 
702 static u8 build_attr(struct vc_data *vc, u8 _color, u8 _intensity, u8 _blink,
703     u8 _underline, u8 _reverse, u8 _italic)
704 {
705 	if (vc->vc_sw->con_build_attr)
706 		return vc->vc_sw->con_build_attr(vc, _color, _intensity,
707 		       _blink, _underline, _reverse, _italic);
708 
709 /*
710  * ++roman: I completely changed the attribute format for monochrome
711  * mode (!can_do_color). The formerly used MDA (monochrome display
712  * adapter) format didn't allow the combination of certain effects.
713  * Now the attribute is just a bit vector:
714  *  Bit 0..1: intensity (0..2)
715  *  Bit 2   : underline
716  *  Bit 3   : reverse
717  *  Bit 7   : blink
718  */
719 	{
720 	u8 a = _color;
721 	if (!vc->vc_can_do_color)
722 		return _intensity |
723 		       (_italic ? 2 : 0) |
724 		       (_underline ? 4 : 0) |
725 		       (_reverse ? 8 : 0) |
726 		       (_blink ? 0x80 : 0);
727 	if (_italic)
728 		a = (a & 0xF0) | vc->vc_itcolor;
729 	else if (_underline)
730 		a = (a & 0xf0) | vc->vc_ulcolor;
731 	else if (_intensity == 0)
732 		a = (a & 0xf0) | vc->vc_halfcolor;
733 	if (_reverse)
734 		a = ((a) & 0x88) | ((((a) >> 4) | ((a) << 4)) & 0x77);
735 	if (_blink)
736 		a ^= 0x80;
737 	if (_intensity == 2)
738 		a ^= 0x08;
739 	if (vc->vc_hi_font_mask == 0x100)
740 		a <<= 1;
741 	return a;
742 	}
743 }
744 
745 static void update_attr(struct vc_data *vc)
746 {
747 	vc->vc_attr = build_attr(vc, vc->vc_color, vc->vc_intensity,
748 	              vc->vc_blink, vc->vc_underline,
749 	              vc->vc_reverse ^ vc->vc_decscnm, vc->vc_italic);
750 	vc->vc_video_erase_char = (build_attr(vc, vc->vc_color, 1, vc->vc_blink, 0, vc->vc_decscnm, 0) << 8) | ' ';
751 }
752 
753 /* Note: inverting the screen twice should revert to the original state */
754 void invert_screen(struct vc_data *vc, int offset, int count, int viewed)
755 {
756 	unsigned short *p;
757 
758 	WARN_CONSOLE_UNLOCKED();
759 
760 	count /= 2;
761 	p = screenpos(vc, offset, viewed);
762 	if (vc->vc_sw->con_invert_region) {
763 		vc->vc_sw->con_invert_region(vc, p, count);
764 	} else {
765 		u16 *q = p;
766 		int cnt = count;
767 		u16 a;
768 
769 		if (!vc->vc_can_do_color) {
770 			while (cnt--) {
771 			    a = scr_readw(q);
772 			    a ^= 0x0800;
773 			    scr_writew(a, q);
774 			    q++;
775 			}
776 		} else if (vc->vc_hi_font_mask == 0x100) {
777 			while (cnt--) {
778 				a = scr_readw(q);
779 				a = ((a) & 0x11ff) | (((a) & 0xe000) >> 4) | (((a) & 0x0e00) << 4);
780 				scr_writew(a, q);
781 				q++;
782 			}
783 		} else {
784 			while (cnt--) {
785 				a = scr_readw(q);
786 				a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) | (((a) & 0x0700) << 4);
787 				scr_writew(a, q);
788 				q++;
789 			}
790 		}
791 	}
792 
793 	if (con_should_update(vc))
794 		do_update_region(vc, (unsigned long) p, count);
795 	notify_update(vc);
796 }
797 
798 /* used by selection: complement pointer position */
799 void complement_pos(struct vc_data *vc, int offset)
800 {
801 	static int old_offset = -1;
802 	static unsigned short old;
803 	static unsigned short oldx, oldy;
804 
805 	WARN_CONSOLE_UNLOCKED();
806 
807 	if (old_offset != -1 && old_offset >= 0 &&
808 	    old_offset < vc->vc_screenbuf_size) {
809 		scr_writew(old, screenpos(vc, old_offset, 1));
810 		if (con_should_update(vc))
811 			vc->vc_sw->con_putc(vc, old, oldy, oldx);
812 		notify_update(vc);
813 	}
814 
815 	old_offset = offset;
816 
817 	if (offset != -1 && offset >= 0 &&
818 	    offset < vc->vc_screenbuf_size) {
819 		unsigned short new;
820 		unsigned short *p;
821 		p = screenpos(vc, offset, 1);
822 		old = scr_readw(p);
823 		new = old ^ vc->vc_complement_mask;
824 		scr_writew(new, p);
825 		if (con_should_update(vc)) {
826 			oldx = (offset >> 1) % vc->vc_cols;
827 			oldy = (offset >> 1) / vc->vc_cols;
828 			vc->vc_sw->con_putc(vc, new, oldy, oldx);
829 		}
830 		notify_update(vc);
831 	}
832 }
833 
834 static void insert_char(struct vc_data *vc, unsigned int nr)
835 {
836 	unsigned short *p = (unsigned short *) vc->vc_pos;
837 
838 	vc_uniscr_insert(vc, nr);
839 	scr_memmovew(p + nr, p, (vc->vc_cols - vc->vc_x - nr) * 2);
840 	scr_memsetw(p, vc->vc_video_erase_char, nr * 2);
841 	vc->vc_need_wrap = 0;
842 	if (con_should_update(vc))
843 		do_update_region(vc, (unsigned long) p,
844 			vc->vc_cols - vc->vc_x);
845 }
846 
847 static void delete_char(struct vc_data *vc, unsigned int nr)
848 {
849 	unsigned short *p = (unsigned short *) vc->vc_pos;
850 
851 	vc_uniscr_delete(vc, nr);
852 	scr_memcpyw(p, p + nr, (vc->vc_cols - vc->vc_x - nr) * 2);
853 	scr_memsetw(p + vc->vc_cols - vc->vc_x - nr, vc->vc_video_erase_char,
854 			nr * 2);
855 	vc->vc_need_wrap = 0;
856 	if (con_should_update(vc))
857 		do_update_region(vc, (unsigned long) p,
858 			vc->vc_cols - vc->vc_x);
859 }
860 
861 static int softcursor_original = -1;
862 
863 static void add_softcursor(struct vc_data *vc)
864 {
865 	int i = scr_readw((u16 *) vc->vc_pos);
866 	u32 type = vc->vc_cursor_type;
867 
868 	if (! (type & 0x10)) return;
869 	if (softcursor_original != -1) return;
870 	softcursor_original = i;
871 	i |= ((type >> 8) & 0xff00 );
872 	i ^= ((type) & 0xff00 );
873 	if ((type & 0x20) && ((softcursor_original & 0x7000) == (i & 0x7000))) i ^= 0x7000;
874 	if ((type & 0x40) && ((i & 0x700) == ((i & 0x7000) >> 4))) i ^= 0x0700;
875 	scr_writew(i, (u16 *) vc->vc_pos);
876 	if (con_should_update(vc))
877 		vc->vc_sw->con_putc(vc, i, vc->vc_y, vc->vc_x);
878 }
879 
880 static void hide_softcursor(struct vc_data *vc)
881 {
882 	if (softcursor_original != -1) {
883 		scr_writew(softcursor_original, (u16 *)vc->vc_pos);
884 		if (con_should_update(vc))
885 			vc->vc_sw->con_putc(vc, softcursor_original,
886 					vc->vc_y, vc->vc_x);
887 		softcursor_original = -1;
888 	}
889 }
890 
891 static void hide_cursor(struct vc_data *vc)
892 {
893 	if (vc == sel_cons)
894 		clear_selection();
895 	vc->vc_sw->con_cursor(vc, CM_ERASE);
896 	hide_softcursor(vc);
897 }
898 
899 static void set_cursor(struct vc_data *vc)
900 {
901 	if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS)
902 		return;
903 	if (vc->vc_deccm) {
904 		if (vc == sel_cons)
905 			clear_selection();
906 		add_softcursor(vc);
907 		if ((vc->vc_cursor_type & 0x0f) != 1)
908 			vc->vc_sw->con_cursor(vc, CM_DRAW);
909 	} else
910 		hide_cursor(vc);
911 }
912 
913 static void set_origin(struct vc_data *vc)
914 {
915 	WARN_CONSOLE_UNLOCKED();
916 
917 	if (!con_is_visible(vc) ||
918 	    !vc->vc_sw->con_set_origin ||
919 	    !vc->vc_sw->con_set_origin(vc))
920 		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
921 	vc->vc_visible_origin = vc->vc_origin;
922 	vc->vc_scr_end = vc->vc_origin + vc->vc_screenbuf_size;
923 	vc->vc_pos = vc->vc_origin + vc->vc_size_row * vc->vc_y + 2 * vc->vc_x;
924 }
925 
926 static void save_screen(struct vc_data *vc)
927 {
928 	WARN_CONSOLE_UNLOCKED();
929 
930 	if (vc->vc_sw->con_save_screen)
931 		vc->vc_sw->con_save_screen(vc);
932 }
933 
934 static void flush_scrollback(struct vc_data *vc)
935 {
936 	WARN_CONSOLE_UNLOCKED();
937 
938 	set_origin(vc);
939 	if (vc->vc_sw->con_flush_scrollback)
940 		vc->vc_sw->con_flush_scrollback(vc);
941 	else
942 		vc->vc_sw->con_switch(vc);
943 }
944 
945 /*
946  *	Redrawing of screen
947  */
948 
949 void clear_buffer_attributes(struct vc_data *vc)
950 {
951 	unsigned short *p = (unsigned short *)vc->vc_origin;
952 	int count = vc->vc_screenbuf_size / 2;
953 	int mask = vc->vc_hi_font_mask | 0xff;
954 
955 	for (; count > 0; count--, p++) {
956 		scr_writew((scr_readw(p)&mask) | (vc->vc_video_erase_char & ~mask), p);
957 	}
958 }
959 
960 void redraw_screen(struct vc_data *vc, int is_switch)
961 {
962 	int redraw = 0;
963 
964 	WARN_CONSOLE_UNLOCKED();
965 
966 	if (!vc) {
967 		/* strange ... */
968 		/* printk("redraw_screen: tty %d not allocated ??\n", new_console+1); */
969 		return;
970 	}
971 
972 	if (is_switch) {
973 		struct vc_data *old_vc = vc_cons[fg_console].d;
974 		if (old_vc == vc)
975 			return;
976 		if (!con_is_visible(vc))
977 			redraw = 1;
978 		*vc->vc_display_fg = vc;
979 		fg_console = vc->vc_num;
980 		hide_cursor(old_vc);
981 		if (!con_is_visible(old_vc)) {
982 			save_screen(old_vc);
983 			set_origin(old_vc);
984 		}
985 		if (tty0dev)
986 			sysfs_notify(&tty0dev->kobj, NULL, "active");
987 	} else {
988 		hide_cursor(vc);
989 		redraw = 1;
990 	}
991 
992 	if (redraw) {
993 		int update;
994 		int old_was_color = vc->vc_can_do_color;
995 
996 		set_origin(vc);
997 		update = vc->vc_sw->con_switch(vc);
998 		set_palette(vc);
999 		/*
1000 		 * If console changed from mono<->color, the best we can do
1001 		 * is to clear the buffer attributes. As it currently stands,
1002 		 * rebuilding new attributes from the old buffer is not doable
1003 		 * without overly complex code.
1004 		 */
1005 		if (old_was_color != vc->vc_can_do_color) {
1006 			update_attr(vc);
1007 			clear_buffer_attributes(vc);
1008 		}
1009 
1010 		if (update && vc->vc_mode != KD_GRAPHICS)
1011 			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
1012 	}
1013 	set_cursor(vc);
1014 	if (is_switch) {
1015 		set_leds();
1016 		compute_shiftstate();
1017 		notify_update(vc);
1018 	}
1019 }
1020 
1021 /*
1022  *	Allocation, freeing and resizing of VTs.
1023  */
1024 
1025 int vc_cons_allocated(unsigned int i)
1026 {
1027 	return (i < MAX_NR_CONSOLES && vc_cons[i].d);
1028 }
1029 
1030 static void visual_init(struct vc_data *vc, int num, int init)
1031 {
1032 	/* ++Geert: vc->vc_sw->con_init determines console size */
1033 	if (vc->vc_sw)
1034 		module_put(vc->vc_sw->owner);
1035 	vc->vc_sw = conswitchp;
1036 #ifndef VT_SINGLE_DRIVER
1037 	if (con_driver_map[num])
1038 		vc->vc_sw = con_driver_map[num];
1039 #endif
1040 	__module_get(vc->vc_sw->owner);
1041 	vc->vc_num = num;
1042 	vc->vc_display_fg = &master_display_fg;
1043 	if (vc->vc_uni_pagedir_loc)
1044 		con_free_unimap(vc);
1045 	vc->vc_uni_pagedir_loc = &vc->vc_uni_pagedir;
1046 	vc->vc_uni_pagedir = NULL;
1047 	vc->vc_hi_font_mask = 0;
1048 	vc->vc_complement_mask = 0;
1049 	vc->vc_can_do_color = 0;
1050 	vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1051 	vc->vc_sw->con_init(vc, init);
1052 	if (!vc->vc_complement_mask)
1053 		vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
1054 	vc->vc_s_complement_mask = vc->vc_complement_mask;
1055 	vc->vc_size_row = vc->vc_cols << 1;
1056 	vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
1057 }
1058 
1059 
1060 static void visual_deinit(struct vc_data *vc)
1061 {
1062 	vc->vc_sw->con_deinit(vc);
1063 	module_put(vc->vc_sw->owner);
1064 }
1065 
1066 int vc_allocate(unsigned int currcons)	/* return 0 on success */
1067 {
1068 	struct vt_notifier_param param;
1069 	struct vc_data *vc;
1070 
1071 	WARN_CONSOLE_UNLOCKED();
1072 
1073 	if (currcons >= MAX_NR_CONSOLES)
1074 		return -ENXIO;
1075 
1076 	if (vc_cons[currcons].d)
1077 		return 0;
1078 
1079 	/* due to the granularity of kmalloc, we waste some memory here */
1080 	/* the alloc is done in two steps, to optimize the common situation
1081 	   of a 25x80 console (structsize=216, screenbuf_size=4000) */
1082 	/* although the numbers above are not valid since long ago, the
1083 	   point is still up-to-date and the comment still has its value
1084 	   even if only as a historical artifact.  --mj, July 1998 */
1085 	param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL);
1086 	if (!vc)
1087 		return -ENOMEM;
1088 
1089 	vc_cons[currcons].d = vc;
1090 	tty_port_init(&vc->port);
1091 	INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
1092 
1093 	visual_init(vc, currcons, 1);
1094 
1095 	if (!*vc->vc_uni_pagedir_loc)
1096 		con_set_default_unimap(vc);
1097 
1098 	vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
1099 	if (!vc->vc_screenbuf)
1100 		goto err_free;
1101 
1102 	/* If no drivers have overridden us and the user didn't pass a
1103 	   boot option, default to displaying the cursor */
1104 	if (global_cursor_default == -1)
1105 		global_cursor_default = 1;
1106 
1107 	vc_init(vc, vc->vc_rows, vc->vc_cols, 1);
1108 	vcs_make_sysfs(currcons);
1109 	atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, &param);
1110 
1111 	return 0;
1112 err_free:
1113 	visual_deinit(vc);
1114 	kfree(vc);
1115 	vc_cons[currcons].d = NULL;
1116 	return -ENOMEM;
1117 }
1118 
1119 static inline int resize_screen(struct vc_data *vc, int width, int height,
1120 				int user)
1121 {
1122 	/* Resizes the resolution of the display adapater */
1123 	int err = 0;
1124 
1125 	if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_resize)
1126 		err = vc->vc_sw->con_resize(vc, width, height, user);
1127 
1128 	return err;
1129 }
1130 
1131 /*
1132  * Change # of rows and columns (0 means unchanged/the size of fg_console)
1133  * [this is to be used together with some user program
1134  * like resize that changes the hardware videomode]
1135  */
1136 #define VC_RESIZE_MAXCOL (32767)
1137 #define VC_RESIZE_MAXROW (32767)
1138 
1139 /**
1140  *	vc_do_resize	-	resizing method for the tty
1141  *	@tty: tty being resized
1142  *	@real_tty: real tty (different to tty if a pty/tty pair)
1143  *	@vc: virtual console private data
1144  *	@cols: columns
1145  *	@lines: lines
1146  *
1147  *	Resize a virtual console, clipping according to the actual constraints.
1148  *	If the caller passes a tty structure then update the termios winsize
1149  *	information and perform any necessary signal handling.
1150  *
1151  *	Caller must hold the console semaphore. Takes the termios rwsem and
1152  *	ctrl_lock of the tty IFF a tty is passed.
1153  */
1154 
1155 static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
1156 				unsigned int cols, unsigned int lines)
1157 {
1158 	unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
1159 	unsigned long end;
1160 	unsigned int old_rows, old_row_size, first_copied_row;
1161 	unsigned int new_cols, new_rows, new_row_size, new_screen_size;
1162 	unsigned int user;
1163 	unsigned short *newscreen;
1164 	struct uni_screen *new_uniscr = NULL;
1165 
1166 	WARN_CONSOLE_UNLOCKED();
1167 
1168 	if (!vc)
1169 		return -ENXIO;
1170 
1171 	user = vc->vc_resize_user;
1172 	vc->vc_resize_user = 0;
1173 
1174 	if (cols > VC_RESIZE_MAXCOL || lines > VC_RESIZE_MAXROW)
1175 		return -EINVAL;
1176 
1177 	new_cols = (cols ? cols : vc->vc_cols);
1178 	new_rows = (lines ? lines : vc->vc_rows);
1179 	new_row_size = new_cols << 1;
1180 	new_screen_size = new_row_size * new_rows;
1181 
1182 	if (new_cols == vc->vc_cols && new_rows == vc->vc_rows)
1183 		return 0;
1184 
1185 	if (new_screen_size > (4 << 20))
1186 		return -EINVAL;
1187 	newscreen = kzalloc(new_screen_size, GFP_USER);
1188 	if (!newscreen)
1189 		return -ENOMEM;
1190 
1191 	if (get_vc_uniscr(vc)) {
1192 		new_uniscr = vc_uniscr_alloc(new_cols, new_rows);
1193 		if (!new_uniscr) {
1194 			kfree(newscreen);
1195 			return -ENOMEM;
1196 		}
1197 	}
1198 
1199 	if (vc == sel_cons)
1200 		clear_selection();
1201 
1202 	old_rows = vc->vc_rows;
1203 	old_row_size = vc->vc_size_row;
1204 
1205 	err = resize_screen(vc, new_cols, new_rows, user);
1206 	if (err) {
1207 		kfree(newscreen);
1208 		kfree(new_uniscr);
1209 		return err;
1210 	}
1211 
1212 	vc->vc_rows = new_rows;
1213 	vc->vc_cols = new_cols;
1214 	vc->vc_size_row = new_row_size;
1215 	vc->vc_screenbuf_size = new_screen_size;
1216 
1217 	rlth = min(old_row_size, new_row_size);
1218 	rrem = new_row_size - rlth;
1219 	old_origin = vc->vc_origin;
1220 	new_origin = (long) newscreen;
1221 	new_scr_end = new_origin + new_screen_size;
1222 
1223 	if (vc->vc_y > new_rows) {
1224 		if (old_rows - vc->vc_y < new_rows) {
1225 			/*
1226 			 * Cursor near the bottom, copy contents from the
1227 			 * bottom of buffer
1228 			 */
1229 			first_copied_row = (old_rows - new_rows);
1230 		} else {
1231 			/*
1232 			 * Cursor is in no man's land, copy 1/2 screenful
1233 			 * from the top and bottom of cursor position
1234 			 */
1235 			first_copied_row = (vc->vc_y - new_rows/2);
1236 		}
1237 		old_origin += first_copied_row * old_row_size;
1238 	} else
1239 		first_copied_row = 0;
1240 	end = old_origin + old_row_size * min(old_rows, new_rows);
1241 
1242 	vc_uniscr_copy_area(new_uniscr, new_cols, new_rows,
1243 			    get_vc_uniscr(vc), rlth/2, first_copied_row,
1244 			    min(old_rows, new_rows));
1245 	vc_uniscr_set(vc, new_uniscr);
1246 
1247 	update_attr(vc);
1248 
1249 	while (old_origin < end) {
1250 		scr_memcpyw((unsigned short *) new_origin,
1251 			    (unsigned short *) old_origin, rlth);
1252 		if (rrem)
1253 			scr_memsetw((void *)(new_origin + rlth),
1254 				    vc->vc_video_erase_char, rrem);
1255 		old_origin += old_row_size;
1256 		new_origin += new_row_size;
1257 	}
1258 	if (new_scr_end > new_origin)
1259 		scr_memsetw((void *)new_origin, vc->vc_video_erase_char,
1260 			    new_scr_end - new_origin);
1261 	kfree(vc->vc_screenbuf);
1262 	vc->vc_screenbuf = newscreen;
1263 	vc->vc_screenbuf_size = new_screen_size;
1264 	set_origin(vc);
1265 
1266 	/* do part of a reset_terminal() */
1267 	vc->vc_top = 0;
1268 	vc->vc_bottom = vc->vc_rows;
1269 	gotoxy(vc, vc->vc_x, vc->vc_y);
1270 	save_cur(vc);
1271 
1272 	if (tty) {
1273 		/* Rewrite the requested winsize data with the actual
1274 		   resulting sizes */
1275 		struct winsize ws;
1276 		memset(&ws, 0, sizeof(ws));
1277 		ws.ws_row = vc->vc_rows;
1278 		ws.ws_col = vc->vc_cols;
1279 		ws.ws_ypixel = vc->vc_scan_lines;
1280 		tty_do_resize(tty, &ws);
1281 	}
1282 
1283 	if (con_is_visible(vc))
1284 		update_screen(vc);
1285 	vt_event_post(VT_EVENT_RESIZE, vc->vc_num, vc->vc_num);
1286 	notify_update(vc);
1287 	return err;
1288 }
1289 
1290 /**
1291  *	vc_resize		-	resize a VT
1292  *	@vc: virtual console
1293  *	@cols: columns
1294  *	@rows: rows
1295  *
1296  *	Resize a virtual console as seen from the console end of things. We
1297  *	use the common vc_do_resize methods to update the structures. The
1298  *	caller must hold the console sem to protect console internals and
1299  *	vc->port.tty
1300  */
1301 
1302 int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
1303 {
1304 	return vc_do_resize(vc->port.tty, vc, cols, rows);
1305 }
1306 
1307 /**
1308  *	vt_resize		-	resize a VT
1309  *	@tty: tty to resize
1310  *	@ws: winsize attributes
1311  *
1312  *	Resize a virtual terminal. This is called by the tty layer as we
1313  *	register our own handler for resizing. The mutual helper does all
1314  *	the actual work.
1315  *
1316  *	Takes the console sem and the called methods then take the tty
1317  *	termios_rwsem and the tty ctrl_lock in that order.
1318  */
1319 static int vt_resize(struct tty_struct *tty, struct winsize *ws)
1320 {
1321 	struct vc_data *vc = tty->driver_data;
1322 	int ret;
1323 
1324 	console_lock();
1325 	ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row);
1326 	console_unlock();
1327 	return ret;
1328 }
1329 
1330 struct vc_data *vc_deallocate(unsigned int currcons)
1331 {
1332 	struct vc_data *vc = NULL;
1333 
1334 	WARN_CONSOLE_UNLOCKED();
1335 
1336 	if (vc_cons_allocated(currcons)) {
1337 		struct vt_notifier_param param;
1338 
1339 		param.vc = vc = vc_cons[currcons].d;
1340 		atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, &param);
1341 		vcs_remove_sysfs(currcons);
1342 		visual_deinit(vc);
1343 		put_pid(vc->vt_pid);
1344 		vc_uniscr_set(vc, NULL);
1345 		kfree(vc->vc_screenbuf);
1346 		vc_cons[currcons].d = NULL;
1347 	}
1348 	return vc;
1349 }
1350 
1351 /*
1352  *	VT102 emulator
1353  */
1354 
1355 enum { EPecma = 0, EPdec, EPeq, EPgt, EPlt};
1356 
1357 #define set_kbd(vc, x)	vt_set_kbd_mode_bit((vc)->vc_num, (x))
1358 #define clr_kbd(vc, x)	vt_clr_kbd_mode_bit((vc)->vc_num, (x))
1359 #define is_kbd(vc, x)	vt_get_kbd_mode_bit((vc)->vc_num, (x))
1360 
1361 #define decarm		VC_REPEAT
1362 #define decckm		VC_CKMODE
1363 #define kbdapplic	VC_APPLIC
1364 #define lnm		VC_CRLF
1365 
1366 /*
1367  * this is what the terminal answers to a ESC-Z or csi0c query.
1368  */
1369 #define VT100ID "\033[?1;2c"
1370 #define VT102ID "\033[?6c"
1371 
1372 const unsigned char color_table[] = { 0, 4, 2, 6, 1, 5, 3, 7,
1373 				       8,12,10,14, 9,13,11,15 };
1374 
1375 /* the default colour table, for VGA+ colour systems */
1376 unsigned char default_red[] = {
1377 	0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa,
1378 	0x55, 0xff, 0x55, 0xff, 0x55, 0xff, 0x55, 0xff
1379 };
1380 module_param_array(default_red, byte, NULL, S_IRUGO | S_IWUSR);
1381 
1382 unsigned char default_grn[] = {
1383 	0x00, 0x00, 0xaa, 0x55, 0x00, 0x00, 0xaa, 0xaa,
1384 	0x55, 0x55, 0xff, 0xff, 0x55, 0x55, 0xff, 0xff
1385 };
1386 module_param_array(default_grn, byte, NULL, S_IRUGO | S_IWUSR);
1387 
1388 unsigned char default_blu[] = {
1389 	0x00, 0x00, 0x00, 0x00, 0xaa, 0xaa, 0xaa, 0xaa,
1390 	0x55, 0x55, 0x55, 0x55, 0xff, 0xff, 0xff, 0xff
1391 };
1392 module_param_array(default_blu, byte, NULL, S_IRUGO | S_IWUSR);
1393 
1394 /*
1395  * gotoxy() must verify all boundaries, because the arguments
1396  * might also be negative. If the given position is out of
1397  * bounds, the cursor is placed at the nearest margin.
1398  */
1399 static void gotoxy(struct vc_data *vc, int new_x, int new_y)
1400 {
1401 	int min_y, max_y;
1402 
1403 	if (new_x < 0)
1404 		vc->vc_x = 0;
1405 	else {
1406 		if (new_x >= vc->vc_cols)
1407 			vc->vc_x = vc->vc_cols - 1;
1408 		else
1409 			vc->vc_x = new_x;
1410 	}
1411 
1412  	if (vc->vc_decom) {
1413 		min_y = vc->vc_top;
1414 		max_y = vc->vc_bottom;
1415 	} else {
1416 		min_y = 0;
1417 		max_y = vc->vc_rows;
1418 	}
1419 	if (new_y < min_y)
1420 		vc->vc_y = min_y;
1421 	else if (new_y >= max_y)
1422 		vc->vc_y = max_y - 1;
1423 	else
1424 		vc->vc_y = new_y;
1425 	vc->vc_pos = vc->vc_origin + vc->vc_y * vc->vc_size_row + (vc->vc_x<<1);
1426 	vc->vc_need_wrap = 0;
1427 }
1428 
1429 /* for absolute user moves, when decom is set */
1430 static void gotoxay(struct vc_data *vc, int new_x, int new_y)
1431 {
1432 	gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y);
1433 }
1434 
1435 void scrollback(struct vc_data *vc)
1436 {
1437 	scrolldelta(-(vc->vc_rows / 2));
1438 }
1439 
1440 void scrollfront(struct vc_data *vc, int lines)
1441 {
1442 	if (!lines)
1443 		lines = vc->vc_rows / 2;
1444 	scrolldelta(lines);
1445 }
1446 
1447 static void lf(struct vc_data *vc)
1448 {
1449     	/* don't scroll if above bottom of scrolling region, or
1450 	 * if below scrolling region
1451 	 */
1452     	if (vc->vc_y + 1 == vc->vc_bottom)
1453 		con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_UP, 1);
1454 	else if (vc->vc_y < vc->vc_rows - 1) {
1455 	    	vc->vc_y++;
1456 		vc->vc_pos += vc->vc_size_row;
1457 	}
1458 	vc->vc_need_wrap = 0;
1459 	notify_write(vc, '\n');
1460 }
1461 
1462 static void ri(struct vc_data *vc)
1463 {
1464     	/* don't scroll if below top of scrolling region, or
1465 	 * if above scrolling region
1466 	 */
1467 	if (vc->vc_y == vc->vc_top)
1468 		con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_DOWN, 1);
1469 	else if (vc->vc_y > 0) {
1470 		vc->vc_y--;
1471 		vc->vc_pos -= vc->vc_size_row;
1472 	}
1473 	vc->vc_need_wrap = 0;
1474 }
1475 
1476 static inline void cr(struct vc_data *vc)
1477 {
1478 	vc->vc_pos -= vc->vc_x << 1;
1479 	vc->vc_need_wrap = vc->vc_x = 0;
1480 	notify_write(vc, '\r');
1481 }
1482 
1483 static inline void bs(struct vc_data *vc)
1484 {
1485 	if (vc->vc_x) {
1486 		vc->vc_pos -= 2;
1487 		vc->vc_x--;
1488 		vc->vc_need_wrap = 0;
1489 		notify_write(vc, '\b');
1490 	}
1491 }
1492 
1493 static inline void del(struct vc_data *vc)
1494 {
1495 	/* ignored */
1496 }
1497 
1498 static void csi_J(struct vc_data *vc, int vpar)
1499 {
1500 	unsigned int count;
1501 	unsigned short * start;
1502 
1503 	switch (vpar) {
1504 		case 0:	/* erase from cursor to end of display */
1505 			vc_uniscr_clear_line(vc, vc->vc_x,
1506 					     vc->vc_cols - vc->vc_x);
1507 			vc_uniscr_clear_lines(vc, vc->vc_y + 1,
1508 					      vc->vc_rows - vc->vc_y - 1);
1509 			count = (vc->vc_scr_end - vc->vc_pos) >> 1;
1510 			start = (unsigned short *)vc->vc_pos;
1511 			break;
1512 		case 1:	/* erase from start to cursor */
1513 			vc_uniscr_clear_line(vc, 0, vc->vc_x + 1);
1514 			vc_uniscr_clear_lines(vc, 0, vc->vc_y);
1515 			count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1;
1516 			start = (unsigned short *)vc->vc_origin;
1517 			break;
1518 		case 3: /* include scrollback */
1519 			flush_scrollback(vc);
1520 			/* fallthrough */
1521 		case 2: /* erase whole display */
1522 			vc_uniscr_clear_lines(vc, 0, vc->vc_rows);
1523 			count = vc->vc_cols * vc->vc_rows;
1524 			start = (unsigned short *)vc->vc_origin;
1525 			break;
1526 		default:
1527 			return;
1528 	}
1529 	scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1530 	if (con_should_update(vc))
1531 		do_update_region(vc, (unsigned long) start, count);
1532 	vc->vc_need_wrap = 0;
1533 }
1534 
1535 static void csi_K(struct vc_data *vc, int vpar)
1536 {
1537 	unsigned int count;
1538 	unsigned short *start = (unsigned short *)vc->vc_pos;
1539 	int offset;
1540 
1541 	switch (vpar) {
1542 		case 0:	/* erase from cursor to end of line */
1543 			offset = 0;
1544 			count = vc->vc_cols - vc->vc_x;
1545 			break;
1546 		case 1:	/* erase from start of line to cursor */
1547 			offset = -vc->vc_x;
1548 			count = vc->vc_x + 1;
1549 			break;
1550 		case 2: /* erase whole line */
1551 			offset = -vc->vc_x;
1552 			count = vc->vc_cols;
1553 			break;
1554 		default:
1555 			return;
1556 	}
1557 	vc_uniscr_clear_line(vc, vc->vc_x + offset, count);
1558 	scr_memsetw(start + offset, vc->vc_video_erase_char, 2 * count);
1559 	vc->vc_need_wrap = 0;
1560 	if (con_should_update(vc))
1561 		do_update_region(vc, (unsigned long)(start + offset), count);
1562 }
1563 
1564 static void csi_X(struct vc_data *vc, int vpar) /* erase the following vpar positions */
1565 {					  /* not vt100? */
1566 	int count;
1567 
1568 	if (!vpar)
1569 		vpar++;
1570 	count = (vpar > vc->vc_cols - vc->vc_x) ? (vc->vc_cols - vc->vc_x) : vpar;
1571 
1572 	vc_uniscr_clear_line(vc, vc->vc_x, count);
1573 	scr_memsetw((unsigned short *)vc->vc_pos, vc->vc_video_erase_char, 2 * count);
1574 	if (con_should_update(vc))
1575 		vc->vc_sw->con_clear(vc, vc->vc_y, vc->vc_x, 1, count);
1576 	vc->vc_need_wrap = 0;
1577 }
1578 
1579 static void default_attr(struct vc_data *vc)
1580 {
1581 	vc->vc_intensity = 1;
1582 	vc->vc_italic = 0;
1583 	vc->vc_underline = 0;
1584 	vc->vc_reverse = 0;
1585 	vc->vc_blink = 0;
1586 	vc->vc_color = vc->vc_def_color;
1587 }
1588 
1589 struct rgb { u8 r; u8 g; u8 b; };
1590 
1591 static void rgb_from_256(int i, struct rgb *c)
1592 {
1593 	if (i < 8) {            /* Standard colours. */
1594 		c->r = i&1 ? 0xaa : 0x00;
1595 		c->g = i&2 ? 0xaa : 0x00;
1596 		c->b = i&4 ? 0xaa : 0x00;
1597 	} else if (i < 16) {
1598 		c->r = i&1 ? 0xff : 0x55;
1599 		c->g = i&2 ? 0xff : 0x55;
1600 		c->b = i&4 ? 0xff : 0x55;
1601 	} else if (i < 232) {   /* 6x6x6 colour cube. */
1602 		c->r = (i - 16) / 36 * 85 / 2;
1603 		c->g = (i - 16) / 6 % 6 * 85 / 2;
1604 		c->b = (i - 16) % 6 * 85 / 2;
1605 	} else                  /* Grayscale ramp. */
1606 		c->r = c->g = c->b = i * 10 - 2312;
1607 }
1608 
1609 static void rgb_foreground(struct vc_data *vc, const struct rgb *c)
1610 {
1611 	u8 hue = 0, max = max3(c->r, c->g, c->b);
1612 
1613 	if (c->r > max / 2)
1614 		hue |= 4;
1615 	if (c->g > max / 2)
1616 		hue |= 2;
1617 	if (c->b > max / 2)
1618 		hue |= 1;
1619 
1620 	if (hue == 7 && max <= 0x55) {
1621 		hue = 0;
1622 		vc->vc_intensity = 2;
1623 	} else if (max > 0xaa)
1624 		vc->vc_intensity = 2;
1625 	else
1626 		vc->vc_intensity = 1;
1627 
1628 	vc->vc_color = (vc->vc_color & 0xf0) | hue;
1629 }
1630 
1631 static void rgb_background(struct vc_data *vc, const struct rgb *c)
1632 {
1633 	/* For backgrounds, err on the dark side. */
1634 	vc->vc_color = (vc->vc_color & 0x0f)
1635 		| (c->r&0x80) >> 1 | (c->g&0x80) >> 2 | (c->b&0x80) >> 3;
1636 }
1637 
1638 /*
1639  * ITU T.416 Higher colour modes. They break the usual properties of SGR codes
1640  * and thus need to be detected and ignored by hand. That standard also
1641  * wants : rather than ; as separators but sequences containing : are currently
1642  * completely ignored by the parser.
1643  *
1644  * Subcommands 3 (CMY) and 4 (CMYK) are so insane there's no point in
1645  * supporting them.
1646  */
1647 static int vc_t416_color(struct vc_data *vc, int i,
1648 		void(*set_color)(struct vc_data *vc, const struct rgb *c))
1649 {
1650 	struct rgb c;
1651 
1652 	i++;
1653 	if (i > vc->vc_npar)
1654 		return i;
1655 
1656 	if (vc->vc_par[i] == 5 && i + 1 <= vc->vc_npar) {
1657 		/* 256 colours */
1658 		i++;
1659 		rgb_from_256(vc->vc_par[i], &c);
1660 	} else if (vc->vc_par[i] == 2 && i + 3 <= vc->vc_npar) {
1661 		/* 24 bit */
1662 		c.r = vc->vc_par[i + 1];
1663 		c.g = vc->vc_par[i + 2];
1664 		c.b = vc->vc_par[i + 3];
1665 		i += 3;
1666 	} else
1667 		return i;
1668 
1669 	set_color(vc, &c);
1670 
1671 	return i;
1672 }
1673 
1674 /* console_lock is held */
1675 static void csi_m(struct vc_data *vc)
1676 {
1677 	int i;
1678 
1679 	for (i = 0; i <= vc->vc_npar; i++)
1680 		switch (vc->vc_par[i]) {
1681 		case 0:	/* all attributes off */
1682 			default_attr(vc);
1683 			break;
1684 		case 1:
1685 			vc->vc_intensity = 2;
1686 			break;
1687 		case 2:
1688 			vc->vc_intensity = 0;
1689 			break;
1690 		case 3:
1691 			vc->vc_italic = 1;
1692 			break;
1693 		case 21:
1694 			/*
1695 			 * No console drivers support double underline, so
1696 			 * convert it to a single underline.
1697 			 */
1698 		case 4:
1699 			vc->vc_underline = 1;
1700 			break;
1701 		case 5:
1702 			vc->vc_blink = 1;
1703 			break;
1704 		case 7:
1705 			vc->vc_reverse = 1;
1706 			break;
1707 		case 10: /* ANSI X3.64-1979 (SCO-ish?)
1708 			  * Select primary font, don't display control chars if
1709 			  * defined, don't set bit 8 on output.
1710 			  */
1711 			vc->vc_translate = set_translate(vc->vc_charset == 0
1712 					? vc->vc_G0_charset
1713 					: vc->vc_G1_charset, vc);
1714 			vc->vc_disp_ctrl = 0;
1715 			vc->vc_toggle_meta = 0;
1716 			break;
1717 		case 11: /* ANSI X3.64-1979 (SCO-ish?)
1718 			  * Select first alternate font, lets chars < 32 be
1719 			  * displayed as ROM chars.
1720 			  */
1721 			vc->vc_translate = set_translate(IBMPC_MAP, vc);
1722 			vc->vc_disp_ctrl = 1;
1723 			vc->vc_toggle_meta = 0;
1724 			break;
1725 		case 12: /* ANSI X3.64-1979 (SCO-ish?)
1726 			  * Select second alternate font, toggle high bit
1727 			  * before displaying as ROM char.
1728 			  */
1729 			vc->vc_translate = set_translate(IBMPC_MAP, vc);
1730 			vc->vc_disp_ctrl = 1;
1731 			vc->vc_toggle_meta = 1;
1732 			break;
1733 		case 22:
1734 			vc->vc_intensity = 1;
1735 			break;
1736 		case 23:
1737 			vc->vc_italic = 0;
1738 			break;
1739 		case 24:
1740 			vc->vc_underline = 0;
1741 			break;
1742 		case 25:
1743 			vc->vc_blink = 0;
1744 			break;
1745 		case 27:
1746 			vc->vc_reverse = 0;
1747 			break;
1748 		case 38:
1749 			i = vc_t416_color(vc, i, rgb_foreground);
1750 			break;
1751 		case 48:
1752 			i = vc_t416_color(vc, i, rgb_background);
1753 			break;
1754 		case 39:
1755 			vc->vc_color = (vc->vc_def_color & 0x0f) |
1756 				(vc->vc_color & 0xf0);
1757 			break;
1758 		case 49:
1759 			vc->vc_color = (vc->vc_def_color & 0xf0) |
1760 				(vc->vc_color & 0x0f);
1761 			break;
1762 		default:
1763 			if (vc->vc_par[i] >= 90 && vc->vc_par[i] <= 107) {
1764 				if (vc->vc_par[i] < 100)
1765 					vc->vc_intensity = 2;
1766 				vc->vc_par[i] -= 60;
1767 			}
1768 			if (vc->vc_par[i] >= 30 && vc->vc_par[i] <= 37)
1769 				vc->vc_color = color_table[vc->vc_par[i] - 30]
1770 					| (vc->vc_color & 0xf0);
1771 			else if (vc->vc_par[i] >= 40 && vc->vc_par[i] <= 47)
1772 				vc->vc_color = (color_table[vc->vc_par[i] - 40] << 4)
1773 					| (vc->vc_color & 0x0f);
1774 			break;
1775 		}
1776 	update_attr(vc);
1777 }
1778 
1779 static void respond_string(const char *p, struct tty_port *port)
1780 {
1781 	while (*p) {
1782 		tty_insert_flip_char(port, *p, 0);
1783 		p++;
1784 	}
1785 	tty_schedule_flip(port);
1786 }
1787 
1788 static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
1789 {
1790 	char buf[40];
1791 
1792 	sprintf(buf, "\033[%d;%dR", vc->vc_y + (vc->vc_decom ? vc->vc_top + 1 : 1), vc->vc_x + 1);
1793 	respond_string(buf, tty->port);
1794 }
1795 
1796 static inline void status_report(struct tty_struct *tty)
1797 {
1798 	respond_string("\033[0n", tty->port);	/* Terminal ok */
1799 }
1800 
1801 static inline void respond_ID(struct tty_struct *tty)
1802 {
1803 	respond_string(VT102ID, tty->port);
1804 }
1805 
1806 void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
1807 {
1808 	char buf[8];
1809 
1810 	sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt), (char)('!' + mrx),
1811 		(char)('!' + mry));
1812 	respond_string(buf, tty->port);
1813 }
1814 
1815 /* invoked via ioctl(TIOCLINUX) and through set_selection_user */
1816 int mouse_reporting(void)
1817 {
1818 	return vc_cons[fg_console].d->vc_report_mouse;
1819 }
1820 
1821 /* console_lock is held */
1822 static void set_mode(struct vc_data *vc, int on_off)
1823 {
1824 	int i;
1825 
1826 	for (i = 0; i <= vc->vc_npar; i++)
1827 		if (vc->vc_priv == EPdec) {
1828 			switch(vc->vc_par[i]) {	/* DEC private modes set/reset */
1829 			case 1:			/* Cursor keys send ^[Ox/^[[x */
1830 				if (on_off)
1831 					set_kbd(vc, decckm);
1832 				else
1833 					clr_kbd(vc, decckm);
1834 				break;
1835 			case 3:	/* 80/132 mode switch unimplemented */
1836 #if 0
1837 				vc_resize(deccolm ? 132 : 80, vc->vc_rows);
1838 				/* this alone does not suffice; some user mode
1839 				   utility has to change the hardware regs */
1840 #endif
1841 				break;
1842 			case 5:			/* Inverted screen on/off */
1843 				if (vc->vc_decscnm != on_off) {
1844 					vc->vc_decscnm = on_off;
1845 					invert_screen(vc, 0, vc->vc_screenbuf_size, 0);
1846 					update_attr(vc);
1847 				}
1848 				break;
1849 			case 6:			/* Origin relative/absolute */
1850 				vc->vc_decom = on_off;
1851 				gotoxay(vc, 0, 0);
1852 				break;
1853 			case 7:			/* Autowrap on/off */
1854 				vc->vc_decawm = on_off;
1855 				break;
1856 			case 8:			/* Autorepeat on/off */
1857 				if (on_off)
1858 					set_kbd(vc, decarm);
1859 				else
1860 					clr_kbd(vc, decarm);
1861 				break;
1862 			case 9:
1863 				vc->vc_report_mouse = on_off ? 1 : 0;
1864 				break;
1865 			case 25:		/* Cursor on/off */
1866 				vc->vc_deccm = on_off;
1867 				break;
1868 			case 1000:
1869 				vc->vc_report_mouse = on_off ? 2 : 0;
1870 				break;
1871 			}
1872 		} else {
1873 			switch(vc->vc_par[i]) {	/* ANSI modes set/reset */
1874 			case 3:			/* Monitor (display ctrls) */
1875 				vc->vc_disp_ctrl = on_off;
1876 				break;
1877 			case 4:			/* Insert Mode on/off */
1878 				vc->vc_decim = on_off;
1879 				break;
1880 			case 20:		/* Lf, Enter == CrLf/Lf */
1881 				if (on_off)
1882 					set_kbd(vc, lnm);
1883 				else
1884 					clr_kbd(vc, lnm);
1885 				break;
1886 			}
1887 		}
1888 }
1889 
1890 /* console_lock is held */
1891 static void setterm_command(struct vc_data *vc)
1892 {
1893 	switch(vc->vc_par[0]) {
1894 		case 1:	/* set color for underline mode */
1895 			if (vc->vc_can_do_color &&
1896 					vc->vc_par[1] < 16) {
1897 				vc->vc_ulcolor = color_table[vc->vc_par[1]];
1898 				if (vc->vc_underline)
1899 					update_attr(vc);
1900 			}
1901 			break;
1902 		case 2:	/* set color for half intensity mode */
1903 			if (vc->vc_can_do_color &&
1904 					vc->vc_par[1] < 16) {
1905 				vc->vc_halfcolor = color_table[vc->vc_par[1]];
1906 				if (vc->vc_intensity == 0)
1907 					update_attr(vc);
1908 			}
1909 			break;
1910 		case 8:	/* store colors as defaults */
1911 			vc->vc_def_color = vc->vc_attr;
1912 			if (vc->vc_hi_font_mask == 0x100)
1913 				vc->vc_def_color >>= 1;
1914 			default_attr(vc);
1915 			update_attr(vc);
1916 			break;
1917 		case 9:	/* set blanking interval */
1918 			blankinterval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60;
1919 			poke_blanked_console();
1920 			break;
1921 		case 10: /* set bell frequency in Hz */
1922 			if (vc->vc_npar >= 1)
1923 				vc->vc_bell_pitch = vc->vc_par[1];
1924 			else
1925 				vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
1926 			break;
1927 		case 11: /* set bell duration in msec */
1928 			if (vc->vc_npar >= 1)
1929 				vc->vc_bell_duration = (vc->vc_par[1] < 2000) ?
1930 					msecs_to_jiffies(vc->vc_par[1]) : 0;
1931 			else
1932 				vc->vc_bell_duration = DEFAULT_BELL_DURATION;
1933 			break;
1934 		case 12: /* bring specified console to the front */
1935 			if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1))
1936 				set_console(vc->vc_par[1] - 1);
1937 			break;
1938 		case 13: /* unblank the screen */
1939 			poke_blanked_console();
1940 			break;
1941 		case 14: /* set vesa powerdown interval */
1942 			vesa_off_interval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60 * HZ;
1943 			break;
1944 		case 15: /* activate the previous console */
1945 			set_console(last_console);
1946 			break;
1947 		case 16: /* set cursor blink duration in msec */
1948 			if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 &&
1949 					vc->vc_par[1] <= USHRT_MAX)
1950 				vc->vc_cur_blink_ms = vc->vc_par[1];
1951 			else
1952 				vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1953 			break;
1954 	}
1955 }
1956 
1957 /* console_lock is held */
1958 static void csi_at(struct vc_data *vc, unsigned int nr)
1959 {
1960 	if (nr > vc->vc_cols - vc->vc_x)
1961 		nr = vc->vc_cols - vc->vc_x;
1962 	else if (!nr)
1963 		nr = 1;
1964 	insert_char(vc, nr);
1965 }
1966 
1967 /* console_lock is held */
1968 static void csi_L(struct vc_data *vc, unsigned int nr)
1969 {
1970 	if (nr > vc->vc_rows - vc->vc_y)
1971 		nr = vc->vc_rows - vc->vc_y;
1972 	else if (!nr)
1973 		nr = 1;
1974 	con_scroll(vc, vc->vc_y, vc->vc_bottom, SM_DOWN, nr);
1975 	vc->vc_need_wrap = 0;
1976 }
1977 
1978 /* console_lock is held */
1979 static void csi_P(struct vc_data *vc, unsigned int nr)
1980 {
1981 	if (nr > vc->vc_cols - vc->vc_x)
1982 		nr = vc->vc_cols - vc->vc_x;
1983 	else if (!nr)
1984 		nr = 1;
1985 	delete_char(vc, nr);
1986 }
1987 
1988 /* console_lock is held */
1989 static void csi_M(struct vc_data *vc, unsigned int nr)
1990 {
1991 	if (nr > vc->vc_rows - vc->vc_y)
1992 		nr = vc->vc_rows - vc->vc_y;
1993 	else if (!nr)
1994 		nr=1;
1995 	con_scroll(vc, vc->vc_y, vc->vc_bottom, SM_UP, nr);
1996 	vc->vc_need_wrap = 0;
1997 }
1998 
1999 /* console_lock is held (except via vc_init->reset_terminal */
2000 static void save_cur(struct vc_data *vc)
2001 {
2002 	vc->vc_saved_x		= vc->vc_x;
2003 	vc->vc_saved_y		= vc->vc_y;
2004 	vc->vc_s_intensity	= vc->vc_intensity;
2005 	vc->vc_s_italic         = vc->vc_italic;
2006 	vc->vc_s_underline	= vc->vc_underline;
2007 	vc->vc_s_blink		= vc->vc_blink;
2008 	vc->vc_s_reverse	= vc->vc_reverse;
2009 	vc->vc_s_charset	= vc->vc_charset;
2010 	vc->vc_s_color		= vc->vc_color;
2011 	vc->vc_saved_G0		= vc->vc_G0_charset;
2012 	vc->vc_saved_G1		= vc->vc_G1_charset;
2013 }
2014 
2015 /* console_lock is held */
2016 static void restore_cur(struct vc_data *vc)
2017 {
2018 	gotoxy(vc, vc->vc_saved_x, vc->vc_saved_y);
2019 	vc->vc_intensity	= vc->vc_s_intensity;
2020 	vc->vc_italic		= vc->vc_s_italic;
2021 	vc->vc_underline	= vc->vc_s_underline;
2022 	vc->vc_blink		= vc->vc_s_blink;
2023 	vc->vc_reverse		= vc->vc_s_reverse;
2024 	vc->vc_charset		= vc->vc_s_charset;
2025 	vc->vc_color		= vc->vc_s_color;
2026 	vc->vc_G0_charset	= vc->vc_saved_G0;
2027 	vc->vc_G1_charset	= vc->vc_saved_G1;
2028 	vc->vc_translate	= set_translate(vc->vc_charset ? vc->vc_G1_charset : vc->vc_G0_charset, vc);
2029 	update_attr(vc);
2030 	vc->vc_need_wrap = 0;
2031 }
2032 
2033 enum { ESnormal, ESesc, ESsquare, ESgetpars, ESfunckey,
2034 	EShash, ESsetG0, ESsetG1, ESpercent, EScsiignore, ESnonstd,
2035 	ESpalette, ESosc };
2036 
2037 /* console_lock is held (except via vc_init()) */
2038 static void reset_terminal(struct vc_data *vc, int do_clear)
2039 {
2040 	vc->vc_top		= 0;
2041 	vc->vc_bottom		= vc->vc_rows;
2042 	vc->vc_state		= ESnormal;
2043 	vc->vc_priv		= EPecma;
2044 	vc->vc_translate	= set_translate(LAT1_MAP, vc);
2045 	vc->vc_G0_charset	= LAT1_MAP;
2046 	vc->vc_G1_charset	= GRAF_MAP;
2047 	vc->vc_charset		= 0;
2048 	vc->vc_need_wrap	= 0;
2049 	vc->vc_report_mouse	= 0;
2050 	vc->vc_utf              = default_utf8;
2051 	vc->vc_utf_count	= 0;
2052 
2053 	vc->vc_disp_ctrl	= 0;
2054 	vc->vc_toggle_meta	= 0;
2055 
2056 	vc->vc_decscnm		= 0;
2057 	vc->vc_decom		= 0;
2058 	vc->vc_decawm		= 1;
2059 	vc->vc_deccm		= global_cursor_default;
2060 	vc->vc_decim		= 0;
2061 
2062 	vt_reset_keyboard(vc->vc_num);
2063 
2064 	vc->vc_cursor_type = cur_default;
2065 	vc->vc_complement_mask = vc->vc_s_complement_mask;
2066 
2067 	default_attr(vc);
2068 	update_attr(vc);
2069 
2070 	vc->vc_tab_stop[0]	=
2071 	vc->vc_tab_stop[1]	=
2072 	vc->vc_tab_stop[2]	=
2073 	vc->vc_tab_stop[3]	=
2074 	vc->vc_tab_stop[4]	=
2075 	vc->vc_tab_stop[5]	=
2076 	vc->vc_tab_stop[6]	=
2077 	vc->vc_tab_stop[7]	= 0x01010101;
2078 
2079 	vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
2080 	vc->vc_bell_duration = DEFAULT_BELL_DURATION;
2081 	vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
2082 
2083 	gotoxy(vc, 0, 0);
2084 	save_cur(vc);
2085 	if (do_clear)
2086 	    csi_J(vc, 2);
2087 }
2088 
2089 /* console_lock is held */
2090 static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
2091 {
2092 	/*
2093 	 *  Control characters can be used in the _middle_
2094 	 *  of an escape sequence.
2095 	 */
2096 	if (vc->vc_state == ESosc && c>=8 && c<=13) /* ... except for OSC */
2097 		return;
2098 	switch (c) {
2099 	case 0:
2100 		return;
2101 	case 7:
2102 		if (vc->vc_state == ESosc)
2103 			vc->vc_state = ESnormal;
2104 		else if (vc->vc_bell_duration)
2105 			kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration);
2106 		return;
2107 	case 8:
2108 		bs(vc);
2109 		return;
2110 	case 9:
2111 		vc->vc_pos -= (vc->vc_x << 1);
2112 		while (vc->vc_x < vc->vc_cols - 1) {
2113 			vc->vc_x++;
2114 			if (vc->vc_tab_stop[7 & (vc->vc_x >> 5)] & (1 << (vc->vc_x & 31)))
2115 				break;
2116 		}
2117 		vc->vc_pos += (vc->vc_x << 1);
2118 		notify_write(vc, '\t');
2119 		return;
2120 	case 10: case 11: case 12:
2121 		lf(vc);
2122 		if (!is_kbd(vc, lnm))
2123 			return;
2124 		/* fall through */
2125 	case 13:
2126 		cr(vc);
2127 		return;
2128 	case 14:
2129 		vc->vc_charset = 1;
2130 		vc->vc_translate = set_translate(vc->vc_G1_charset, vc);
2131 		vc->vc_disp_ctrl = 1;
2132 		return;
2133 	case 15:
2134 		vc->vc_charset = 0;
2135 		vc->vc_translate = set_translate(vc->vc_G0_charset, vc);
2136 		vc->vc_disp_ctrl = 0;
2137 		return;
2138 	case 24: case 26:
2139 		vc->vc_state = ESnormal;
2140 		return;
2141 	case 27:
2142 		vc->vc_state = ESesc;
2143 		return;
2144 	case 127:
2145 		del(vc);
2146 		return;
2147 	case 128+27:
2148 		vc->vc_state = ESsquare;
2149 		return;
2150 	}
2151 	switch(vc->vc_state) {
2152 	case ESesc:
2153 		vc->vc_state = ESnormal;
2154 		switch (c) {
2155 		case '[':
2156 			vc->vc_state = ESsquare;
2157 			return;
2158 		case ']':
2159 			vc->vc_state = ESnonstd;
2160 			return;
2161 		case '%':
2162 			vc->vc_state = ESpercent;
2163 			return;
2164 		case 'E':
2165 			cr(vc);
2166 			lf(vc);
2167 			return;
2168 		case 'M':
2169 			ri(vc);
2170 			return;
2171 		case 'D':
2172 			lf(vc);
2173 			return;
2174 		case 'H':
2175 			vc->vc_tab_stop[7 & (vc->vc_x >> 5)] |= (1 << (vc->vc_x & 31));
2176 			return;
2177 		case 'Z':
2178 			respond_ID(tty);
2179 			return;
2180 		case '7':
2181 			save_cur(vc);
2182 			return;
2183 		case '8':
2184 			restore_cur(vc);
2185 			return;
2186 		case '(':
2187 			vc->vc_state = ESsetG0;
2188 			return;
2189 		case ')':
2190 			vc->vc_state = ESsetG1;
2191 			return;
2192 		case '#':
2193 			vc->vc_state = EShash;
2194 			return;
2195 		case 'c':
2196 			reset_terminal(vc, 1);
2197 			return;
2198 		case '>':  /* Numeric keypad */
2199 			clr_kbd(vc, kbdapplic);
2200 			return;
2201 		case '=':  /* Appl. keypad */
2202 			set_kbd(vc, kbdapplic);
2203 			return;
2204 		}
2205 		return;
2206 	case ESnonstd:
2207 		if (c=='P') {   /* palette escape sequence */
2208 			for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2209 				vc->vc_par[vc->vc_npar] = 0;
2210 			vc->vc_npar = 0;
2211 			vc->vc_state = ESpalette;
2212 			return;
2213 		} else if (c=='R') {   /* reset palette */
2214 			reset_palette(vc);
2215 			vc->vc_state = ESnormal;
2216 		} else if (c>='0' && c<='9')
2217 			vc->vc_state = ESosc;
2218 		else
2219 			vc->vc_state = ESnormal;
2220 		return;
2221 	case ESpalette:
2222 		if (isxdigit(c)) {
2223 			vc->vc_par[vc->vc_npar++] = hex_to_bin(c);
2224 			if (vc->vc_npar == 7) {
2225 				int i = vc->vc_par[0] * 3, j = 1;
2226 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2227 				vc->vc_palette[i++] += vc->vc_par[j++];
2228 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2229 				vc->vc_palette[i++] += vc->vc_par[j++];
2230 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2231 				vc->vc_palette[i] += vc->vc_par[j];
2232 				set_palette(vc);
2233 				vc->vc_state = ESnormal;
2234 			}
2235 		} else
2236 			vc->vc_state = ESnormal;
2237 		return;
2238 	case ESsquare:
2239 		for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2240 			vc->vc_par[vc->vc_npar] = 0;
2241 		vc->vc_npar = 0;
2242 		vc->vc_state = ESgetpars;
2243 		if (c == '[') { /* Function key */
2244 			vc->vc_state=ESfunckey;
2245 			return;
2246 		}
2247 		switch (c) {
2248 		case '?':
2249 			vc->vc_priv = EPdec;
2250 			return;
2251 		case '>':
2252 			vc->vc_priv = EPgt;
2253 			return;
2254 		case '=':
2255 			vc->vc_priv = EPeq;
2256 			return;
2257 		case '<':
2258 			vc->vc_priv = EPlt;
2259 			return;
2260 		}
2261 		vc->vc_priv = EPecma;
2262 		/* fall through */
2263 	case ESgetpars:
2264 		if (c == ';' && vc->vc_npar < NPAR - 1) {
2265 			vc->vc_npar++;
2266 			return;
2267 		} else if (c>='0' && c<='9') {
2268 			vc->vc_par[vc->vc_npar] *= 10;
2269 			vc->vc_par[vc->vc_npar] += c - '0';
2270 			return;
2271 		}
2272 		if (c >= 0x20 && c <= 0x3f) { /* 0x2x, 0x3a and 0x3c - 0x3f */
2273 			vc->vc_state = EScsiignore;
2274 			return;
2275 		}
2276 		vc->vc_state = ESnormal;
2277 		switch(c) {
2278 		case 'h':
2279 			if (vc->vc_priv <= EPdec)
2280 				set_mode(vc, 1);
2281 			return;
2282 		case 'l':
2283 			if (vc->vc_priv <= EPdec)
2284 				set_mode(vc, 0);
2285 			return;
2286 		case 'c':
2287 			if (vc->vc_priv == EPdec) {
2288 				if (vc->vc_par[0])
2289 					vc->vc_cursor_type = vc->vc_par[0] | (vc->vc_par[1] << 8) | (vc->vc_par[2] << 16);
2290 				else
2291 					vc->vc_cursor_type = cur_default;
2292 				return;
2293 			}
2294 			break;
2295 		case 'm':
2296 			if (vc->vc_priv == EPdec) {
2297 				clear_selection();
2298 				if (vc->vc_par[0])
2299 					vc->vc_complement_mask = vc->vc_par[0] << 8 | vc->vc_par[1];
2300 				else
2301 					vc->vc_complement_mask = vc->vc_s_complement_mask;
2302 				return;
2303 			}
2304 			break;
2305 		case 'n':
2306 			if (vc->vc_priv == EPecma) {
2307 				if (vc->vc_par[0] == 5)
2308 					status_report(tty);
2309 				else if (vc->vc_par[0] == 6)
2310 					cursor_report(vc, tty);
2311 			}
2312 			return;
2313 		}
2314 		if (vc->vc_priv != EPecma) {
2315 			vc->vc_priv = EPecma;
2316 			return;
2317 		}
2318 		switch(c) {
2319 		case 'G': case '`':
2320 			if (vc->vc_par[0])
2321 				vc->vc_par[0]--;
2322 			gotoxy(vc, vc->vc_par[0], vc->vc_y);
2323 			return;
2324 		case 'A':
2325 			if (!vc->vc_par[0])
2326 				vc->vc_par[0]++;
2327 			gotoxy(vc, vc->vc_x, vc->vc_y - vc->vc_par[0]);
2328 			return;
2329 		case 'B': case 'e':
2330 			if (!vc->vc_par[0])
2331 				vc->vc_par[0]++;
2332 			gotoxy(vc, vc->vc_x, vc->vc_y + vc->vc_par[0]);
2333 			return;
2334 		case 'C': case 'a':
2335 			if (!vc->vc_par[0])
2336 				vc->vc_par[0]++;
2337 			gotoxy(vc, vc->vc_x + vc->vc_par[0], vc->vc_y);
2338 			return;
2339 		case 'D':
2340 			if (!vc->vc_par[0])
2341 				vc->vc_par[0]++;
2342 			gotoxy(vc, vc->vc_x - vc->vc_par[0], vc->vc_y);
2343 			return;
2344 		case 'E':
2345 			if (!vc->vc_par[0])
2346 				vc->vc_par[0]++;
2347 			gotoxy(vc, 0, vc->vc_y + vc->vc_par[0]);
2348 			return;
2349 		case 'F':
2350 			if (!vc->vc_par[0])
2351 				vc->vc_par[0]++;
2352 			gotoxy(vc, 0, vc->vc_y - vc->vc_par[0]);
2353 			return;
2354 		case 'd':
2355 			if (vc->vc_par[0])
2356 				vc->vc_par[0]--;
2357 			gotoxay(vc, vc->vc_x ,vc->vc_par[0]);
2358 			return;
2359 		case 'H': case 'f':
2360 			if (vc->vc_par[0])
2361 				vc->vc_par[0]--;
2362 			if (vc->vc_par[1])
2363 				vc->vc_par[1]--;
2364 			gotoxay(vc, vc->vc_par[1], vc->vc_par[0]);
2365 			return;
2366 		case 'J':
2367 			csi_J(vc, vc->vc_par[0]);
2368 			return;
2369 		case 'K':
2370 			csi_K(vc, vc->vc_par[0]);
2371 			return;
2372 		case 'L':
2373 			csi_L(vc, vc->vc_par[0]);
2374 			return;
2375 		case 'M':
2376 			csi_M(vc, vc->vc_par[0]);
2377 			return;
2378 		case 'P':
2379 			csi_P(vc, vc->vc_par[0]);
2380 			return;
2381 		case 'c':
2382 			if (!vc->vc_par[0])
2383 				respond_ID(tty);
2384 			return;
2385 		case 'g':
2386 			if (!vc->vc_par[0])
2387 				vc->vc_tab_stop[7 & (vc->vc_x >> 5)] &= ~(1 << (vc->vc_x & 31));
2388 			else if (vc->vc_par[0] == 3) {
2389 				vc->vc_tab_stop[0] =
2390 					vc->vc_tab_stop[1] =
2391 					vc->vc_tab_stop[2] =
2392 					vc->vc_tab_stop[3] =
2393 					vc->vc_tab_stop[4] =
2394 					vc->vc_tab_stop[5] =
2395 					vc->vc_tab_stop[6] =
2396 					vc->vc_tab_stop[7] = 0;
2397 			}
2398 			return;
2399 		case 'm':
2400 			csi_m(vc);
2401 			return;
2402 		case 'q': /* DECLL - but only 3 leds */
2403 			/* map 0,1,2,3 to 0,1,2,4 */
2404 			if (vc->vc_par[0] < 4)
2405 				vt_set_led_state(vc->vc_num,
2406 					    (vc->vc_par[0] < 3) ? vc->vc_par[0] : 4);
2407 			return;
2408 		case 'r':
2409 			if (!vc->vc_par[0])
2410 				vc->vc_par[0]++;
2411 			if (!vc->vc_par[1])
2412 				vc->vc_par[1] = vc->vc_rows;
2413 			/* Minimum allowed region is 2 lines */
2414 			if (vc->vc_par[0] < vc->vc_par[1] &&
2415 			    vc->vc_par[1] <= vc->vc_rows) {
2416 				vc->vc_top = vc->vc_par[0] - 1;
2417 				vc->vc_bottom = vc->vc_par[1];
2418 				gotoxay(vc, 0, 0);
2419 			}
2420 			return;
2421 		case 's':
2422 			save_cur(vc);
2423 			return;
2424 		case 'u':
2425 			restore_cur(vc);
2426 			return;
2427 		case 'X':
2428 			csi_X(vc, vc->vc_par[0]);
2429 			return;
2430 		case '@':
2431 			csi_at(vc, vc->vc_par[0]);
2432 			return;
2433 		case ']': /* setterm functions */
2434 			setterm_command(vc);
2435 			return;
2436 		}
2437 		return;
2438 	case EScsiignore:
2439 		if (c >= 20 && c <= 0x3f)
2440 			return;
2441 		vc->vc_state = ESnormal;
2442 		return;
2443 	case ESpercent:
2444 		vc->vc_state = ESnormal;
2445 		switch (c) {
2446 		case '@':  /* defined in ISO 2022 */
2447 			vc->vc_utf = 0;
2448 			return;
2449 		case 'G':  /* prelim official escape code */
2450 		case '8':  /* retained for compatibility */
2451 			vc->vc_utf = 1;
2452 			return;
2453 		}
2454 		return;
2455 	case ESfunckey:
2456 		vc->vc_state = ESnormal;
2457 		return;
2458 	case EShash:
2459 		vc->vc_state = ESnormal;
2460 		if (c == '8') {
2461 			/* DEC screen alignment test. kludge :-) */
2462 			vc->vc_video_erase_char =
2463 				(vc->vc_video_erase_char & 0xff00) | 'E';
2464 			csi_J(vc, 2);
2465 			vc->vc_video_erase_char =
2466 				(vc->vc_video_erase_char & 0xff00) | ' ';
2467 			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
2468 		}
2469 		return;
2470 	case ESsetG0:
2471 		if (c == '0')
2472 			vc->vc_G0_charset = GRAF_MAP;
2473 		else if (c == 'B')
2474 			vc->vc_G0_charset = LAT1_MAP;
2475 		else if (c == 'U')
2476 			vc->vc_G0_charset = IBMPC_MAP;
2477 		else if (c == 'K')
2478 			vc->vc_G0_charset = USER_MAP;
2479 		if (vc->vc_charset == 0)
2480 			vc->vc_translate = set_translate(vc->vc_G0_charset, vc);
2481 		vc->vc_state = ESnormal;
2482 		return;
2483 	case ESsetG1:
2484 		if (c == '0')
2485 			vc->vc_G1_charset = GRAF_MAP;
2486 		else if (c == 'B')
2487 			vc->vc_G1_charset = LAT1_MAP;
2488 		else if (c == 'U')
2489 			vc->vc_G1_charset = IBMPC_MAP;
2490 		else if (c == 'K')
2491 			vc->vc_G1_charset = USER_MAP;
2492 		if (vc->vc_charset == 1)
2493 			vc->vc_translate = set_translate(vc->vc_G1_charset, vc);
2494 		vc->vc_state = ESnormal;
2495 		return;
2496 	case ESosc:
2497 		return;
2498 	default:
2499 		vc->vc_state = ESnormal;
2500 	}
2501 }
2502 
2503 /* is_double_width() is based on the wcwidth() implementation by
2504  * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
2505  * Latest version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
2506  */
2507 struct interval {
2508 	uint32_t first;
2509 	uint32_t last;
2510 };
2511 
2512 static int ucs_cmp(const void *key, const void *elt)
2513 {
2514 	uint32_t ucs = *(uint32_t *)key;
2515 	struct interval e = *(struct interval *) elt;
2516 
2517 	if (ucs > e.last)
2518 		return 1;
2519 	else if (ucs < e.first)
2520 		return -1;
2521 	return 0;
2522 }
2523 
2524 static int is_double_width(uint32_t ucs)
2525 {
2526 	static const struct interval double_width[] = {
2527 		{ 0x1100, 0x115F }, { 0x2329, 0x232A }, { 0x2E80, 0x303E },
2528 		{ 0x3040, 0xA4CF }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF },
2529 		{ 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 },
2530 		{ 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }
2531 	};
2532 	if (ucs < double_width[0].first ||
2533 	    ucs > double_width[ARRAY_SIZE(double_width) - 1].last)
2534 		return 0;
2535 
2536 	return bsearch(&ucs, double_width, ARRAY_SIZE(double_width),
2537 			sizeof(struct interval), ucs_cmp) != NULL;
2538 }
2539 
2540 static void con_flush(struct vc_data *vc, unsigned long draw_from,
2541 		unsigned long draw_to, int *draw_x)
2542 {
2543 	if (*draw_x < 0)
2544 		return;
2545 
2546 	vc->vc_sw->con_putcs(vc, (u16 *)draw_from,
2547 			(u16 *)draw_to - (u16 *)draw_from, vc->vc_y, *draw_x);
2548 	*draw_x = -1;
2549 }
2550 
2551 /* acquires console_lock */
2552 static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int count)
2553 {
2554 	int c, next_c, tc, ok, n = 0, draw_x = -1;
2555 	unsigned int currcons;
2556 	unsigned long draw_from = 0, draw_to = 0;
2557 	struct vc_data *vc;
2558 	unsigned char vc_attr;
2559 	struct vt_notifier_param param;
2560 	uint8_t rescan;
2561 	uint8_t inverse;
2562 	uint8_t width;
2563 	u16 himask, charmask;
2564 
2565 	if (in_interrupt())
2566 		return count;
2567 
2568 	might_sleep();
2569 
2570 	console_lock();
2571 	vc = tty->driver_data;
2572 	if (vc == NULL) {
2573 		pr_err("vt: argh, driver_data is NULL !\n");
2574 		console_unlock();
2575 		return 0;
2576 	}
2577 
2578 	currcons = vc->vc_num;
2579 	if (!vc_cons_allocated(currcons)) {
2580 		/* could this happen? */
2581 		pr_warn_once("con_write: tty %d not allocated\n", currcons+1);
2582 		console_unlock();
2583 		return 0;
2584 	}
2585 
2586 	himask = vc->vc_hi_font_mask;
2587 	charmask = himask ? 0x1ff : 0xff;
2588 
2589 	/* undraw cursor first */
2590 	if (con_is_fg(vc))
2591 		hide_cursor(vc);
2592 
2593 	param.vc = vc;
2594 
2595 	while (!tty->stopped && count) {
2596 		int orig = *buf;
2597 		c = orig;
2598 		buf++;
2599 		n++;
2600 		count--;
2601 		rescan = 0;
2602 		inverse = 0;
2603 		width = 1;
2604 
2605 		/* Do no translation at all in control states */
2606 		if (vc->vc_state != ESnormal) {
2607 			tc = c;
2608 		} else if (vc->vc_utf && !vc->vc_disp_ctrl) {
2609 		    /* Combine UTF-8 into Unicode in vc_utf_char.
2610 		     * vc_utf_count is the number of continuation bytes still
2611 		     * expected to arrive.
2612 		     * vc_npar is the number of continuation bytes arrived so
2613 		     * far
2614 		     */
2615 rescan_last_byte:
2616 		    if ((c & 0xc0) == 0x80) {
2617 			/* Continuation byte received */
2618 			static const uint32_t utf8_length_changes[] = { 0x0000007f, 0x000007ff, 0x0000ffff, 0x001fffff, 0x03ffffff, 0x7fffffff };
2619 			if (vc->vc_utf_count) {
2620 			    vc->vc_utf_char = (vc->vc_utf_char << 6) | (c & 0x3f);
2621 			    vc->vc_npar++;
2622 			    if (--vc->vc_utf_count) {
2623 				/* Still need some bytes */
2624 				continue;
2625 			    }
2626 			    /* Got a whole character */
2627 			    c = vc->vc_utf_char;
2628 			    /* Reject overlong sequences */
2629 			    if (c <= utf8_length_changes[vc->vc_npar - 1] ||
2630 					c > utf8_length_changes[vc->vc_npar])
2631 				c = 0xfffd;
2632 			} else {
2633 			    /* Unexpected continuation byte */
2634 			    vc->vc_utf_count = 0;
2635 			    c = 0xfffd;
2636 			}
2637 		    } else {
2638 			/* Single ASCII byte or first byte of a sequence received */
2639 			if (vc->vc_utf_count) {
2640 			    /* Continuation byte expected */
2641 			    rescan = 1;
2642 			    vc->vc_utf_count = 0;
2643 			    c = 0xfffd;
2644 			} else if (c > 0x7f) {
2645 			    /* First byte of a multibyte sequence received */
2646 			    vc->vc_npar = 0;
2647 			    if ((c & 0xe0) == 0xc0) {
2648 				vc->vc_utf_count = 1;
2649 				vc->vc_utf_char = (c & 0x1f);
2650 			    } else if ((c & 0xf0) == 0xe0) {
2651 				vc->vc_utf_count = 2;
2652 				vc->vc_utf_char = (c & 0x0f);
2653 			    } else if ((c & 0xf8) == 0xf0) {
2654 				vc->vc_utf_count = 3;
2655 				vc->vc_utf_char = (c & 0x07);
2656 			    } else if ((c & 0xfc) == 0xf8) {
2657 				vc->vc_utf_count = 4;
2658 				vc->vc_utf_char = (c & 0x03);
2659 			    } else if ((c & 0xfe) == 0xfc) {
2660 				vc->vc_utf_count = 5;
2661 				vc->vc_utf_char = (c & 0x01);
2662 			    } else {
2663 				/* 254 and 255 are invalid */
2664 				c = 0xfffd;
2665 			    }
2666 			    if (vc->vc_utf_count) {
2667 				/* Still need some bytes */
2668 				continue;
2669 			    }
2670 			}
2671 			/* Nothing to do if an ASCII byte was received */
2672 		    }
2673 		    /* End of UTF-8 decoding. */
2674 		    /* c is the received character, or U+FFFD for invalid sequences. */
2675 		    /* Replace invalid Unicode code points with U+FFFD too */
2676 		    if ((c >= 0xd800 && c <= 0xdfff) || c == 0xfffe || c == 0xffff)
2677 			c = 0xfffd;
2678 		    tc = c;
2679 		} else {	/* no utf or alternate charset mode */
2680 		    tc = vc_translate(vc, c);
2681 		}
2682 
2683 		param.c = tc;
2684 		if (atomic_notifier_call_chain(&vt_notifier_list, VT_PREWRITE,
2685 					&param) == NOTIFY_STOP)
2686 			continue;
2687 
2688                 /* If the original code was a control character we
2689                  * only allow a glyph to be displayed if the code is
2690                  * not normally used (such as for cursor movement) or
2691                  * if the disp_ctrl mode has been explicitly enabled.
2692                  * Certain characters (as given by the CTRL_ALWAYS
2693                  * bitmap) are always displayed as control characters,
2694                  * as the console would be pretty useless without
2695                  * them; to display an arbitrary font position use the
2696                  * direct-to-font zone in UTF-8 mode.
2697                  */
2698                 ok = tc && (c >= 32 ||
2699 			    !(vc->vc_disp_ctrl ? (CTRL_ALWAYS >> c) & 1 :
2700 				  vc->vc_utf || ((CTRL_ACTION >> c) & 1)))
2701 			&& (c != 127 || vc->vc_disp_ctrl)
2702 			&& (c != 128+27);
2703 
2704 		if (vc->vc_state == ESnormal && ok) {
2705 			if (vc->vc_utf && !vc->vc_disp_ctrl) {
2706 				if (is_double_width(c))
2707 					width = 2;
2708 			}
2709 			/* Now try to find out how to display it */
2710 			tc = conv_uni_to_pc(vc, tc);
2711 			if (tc & ~charmask) {
2712 				if (tc == -1 || tc == -2) {
2713 				    continue; /* nothing to display */
2714 				}
2715 				/* Glyph not found */
2716 				if ((!(vc->vc_utf && !vc->vc_disp_ctrl) || c < 128) && !(c & ~charmask)) {
2717 				    /* In legacy mode use the glyph we get by a 1:1 mapping.
2718 				       This would make absolutely no sense with Unicode in mind,
2719 				       but do this for ASCII characters since a font may lack
2720 				       Unicode mapping info and we don't want to end up with
2721 				       having question marks only. */
2722 				    tc = c;
2723 				} else {
2724 				    /* Display U+FFFD. If it's not found, display an inverse question mark. */
2725 				    tc = conv_uni_to_pc(vc, 0xfffd);
2726 				    if (tc < 0) {
2727 					inverse = 1;
2728 					tc = conv_uni_to_pc(vc, '?');
2729 					if (tc < 0) tc = '?';
2730 				    }
2731 				}
2732 			}
2733 
2734 			if (!inverse) {
2735 				vc_attr = vc->vc_attr;
2736 			} else {
2737 				/* invert vc_attr */
2738 				if (!vc->vc_can_do_color) {
2739 					vc_attr = (vc->vc_attr) ^ 0x08;
2740 				} else if (vc->vc_hi_font_mask == 0x100) {
2741 					vc_attr = ((vc->vc_attr) & 0x11) | (((vc->vc_attr) & 0xe0) >> 4) | (((vc->vc_attr) & 0x0e) << 4);
2742 				} else {
2743 					vc_attr = ((vc->vc_attr) & 0x88) | (((vc->vc_attr) & 0x70) >> 4) | (((vc->vc_attr) & 0x07) << 4);
2744 				}
2745 				con_flush(vc, draw_from, draw_to, &draw_x);
2746 			}
2747 
2748 			next_c = c;
2749 			while (1) {
2750 				if (vc->vc_need_wrap || vc->vc_decim)
2751 					con_flush(vc, draw_from, draw_to,
2752 							&draw_x);
2753 				if (vc->vc_need_wrap) {
2754 					cr(vc);
2755 					lf(vc);
2756 				}
2757 				if (vc->vc_decim)
2758 					insert_char(vc, 1);
2759 				vc_uniscr_putc(vc, next_c);
2760 				scr_writew(himask ?
2761 					     ((vc_attr << 8) & ~himask) + ((tc & 0x100) ? himask : 0) + (tc & 0xff) :
2762 					     (vc_attr << 8) + tc,
2763 					   (u16 *) vc->vc_pos);
2764 				if (con_should_update(vc) && draw_x < 0) {
2765 					draw_x = vc->vc_x;
2766 					draw_from = vc->vc_pos;
2767 				}
2768 				if (vc->vc_x == vc->vc_cols - 1) {
2769 					vc->vc_need_wrap = vc->vc_decawm;
2770 					draw_to = vc->vc_pos + 2;
2771 				} else {
2772 					vc->vc_x++;
2773 					draw_to = (vc->vc_pos += 2);
2774 				}
2775 
2776 				if (!--width) break;
2777 
2778 				tc = conv_uni_to_pc(vc, ' '); /* A space is printed in the second column */
2779 				if (tc < 0) tc = ' ';
2780 				next_c = ' ';
2781 			}
2782 			notify_write(vc, c);
2783 
2784 			if (inverse)
2785 				con_flush(vc, draw_from, draw_to, &draw_x);
2786 
2787 			if (rescan) {
2788 				rescan = 0;
2789 				inverse = 0;
2790 				width = 1;
2791 				c = orig;
2792 				goto rescan_last_byte;
2793 			}
2794 			continue;
2795 		}
2796 		con_flush(vc, draw_from, draw_to, &draw_x);
2797 		do_con_trol(tty, vc, orig);
2798 	}
2799 	con_flush(vc, draw_from, draw_to, &draw_x);
2800 	vc_uniscr_debug_check(vc);
2801 	console_conditional_schedule();
2802 	notify_update(vc);
2803 	console_unlock();
2804 	return n;
2805 }
2806 
2807 /*
2808  * This is the console switching callback.
2809  *
2810  * Doing console switching in a process context allows
2811  * us to do the switches asynchronously (needed when we want
2812  * to switch due to a keyboard interrupt).  Synchronization
2813  * with other console code and prevention of re-entrancy is
2814  * ensured with console_lock.
2815  */
2816 static void console_callback(struct work_struct *ignored)
2817 {
2818 	console_lock();
2819 
2820 	if (want_console >= 0) {
2821 		if (want_console != fg_console &&
2822 		    vc_cons_allocated(want_console)) {
2823 			hide_cursor(vc_cons[fg_console].d);
2824 			change_console(vc_cons[want_console].d);
2825 			/* we only changed when the console had already
2826 			   been allocated - a new console is not created
2827 			   in an interrupt routine */
2828 		}
2829 		want_console = -1;
2830 	}
2831 	if (do_poke_blanked_console) { /* do not unblank for a LED change */
2832 		do_poke_blanked_console = 0;
2833 		poke_blanked_console();
2834 	}
2835 	if (scrollback_delta) {
2836 		struct vc_data *vc = vc_cons[fg_console].d;
2837 		clear_selection();
2838 		if (vc->vc_mode == KD_TEXT && vc->vc_sw->con_scrolldelta)
2839 			vc->vc_sw->con_scrolldelta(vc, scrollback_delta);
2840 		scrollback_delta = 0;
2841 	}
2842 	if (blank_timer_expired) {
2843 		do_blank_screen(0);
2844 		blank_timer_expired = 0;
2845 	}
2846 	notify_update(vc_cons[fg_console].d);
2847 
2848 	console_unlock();
2849 }
2850 
2851 int set_console(int nr)
2852 {
2853 	struct vc_data *vc = vc_cons[fg_console].d;
2854 
2855 	if (!vc_cons_allocated(nr) || vt_dont_switch ||
2856 		(vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) {
2857 
2858 		/*
2859 		 * Console switch will fail in console_callback() or
2860 		 * change_console() so there is no point scheduling
2861 		 * the callback
2862 		 *
2863 		 * Existing set_console() users don't check the return
2864 		 * value so this shouldn't break anything
2865 		 */
2866 		return -EINVAL;
2867 	}
2868 
2869 	want_console = nr;
2870 	schedule_console_callback();
2871 
2872 	return 0;
2873 }
2874 
2875 struct tty_driver *console_driver;
2876 
2877 #ifdef CONFIG_VT_CONSOLE
2878 
2879 /**
2880  * vt_kmsg_redirect() - Sets/gets the kernel message console
2881  * @new:	The new virtual terminal number or -1 if the console should stay
2882  * 		unchanged
2883  *
2884  * By default, the kernel messages are always printed on the current virtual
2885  * console. However, the user may modify that default with the
2886  * TIOCL_SETKMSGREDIRECT ioctl call.
2887  *
2888  * This function sets the kernel message console to be @new. It returns the old
2889  * virtual console number. The virtual terminal number 0 (both as parameter and
2890  * return value) means no redirection (i.e. always printed on the currently
2891  * active console).
2892  *
2893  * The parameter -1 means that only the current console is returned, but the
2894  * value is not modified. You may use the macro vt_get_kmsg_redirect() in that
2895  * case to make the code more understandable.
2896  *
2897  * When the kernel is compiled without CONFIG_VT_CONSOLE, this function ignores
2898  * the parameter and always returns 0.
2899  */
2900 int vt_kmsg_redirect(int new)
2901 {
2902 	static int kmsg_con;
2903 
2904 	if (new != -1)
2905 		return xchg(&kmsg_con, new);
2906 	else
2907 		return kmsg_con;
2908 }
2909 
2910 /*
2911  *	Console on virtual terminal
2912  *
2913  * The console must be locked when we get here.
2914  */
2915 
2916 static void vt_console_print(struct console *co, const char *b, unsigned count)
2917 {
2918 	struct vc_data *vc = vc_cons[fg_console].d;
2919 	unsigned char c;
2920 	static DEFINE_SPINLOCK(printing_lock);
2921 	const ushort *start;
2922 	ushort start_x, cnt;
2923 	int kmsg_console;
2924 
2925 	/* console busy or not yet initialized */
2926 	if (!printable)
2927 		return;
2928 	if (!spin_trylock(&printing_lock))
2929 		return;
2930 
2931 	kmsg_console = vt_get_kmsg_redirect();
2932 	if (kmsg_console && vc_cons_allocated(kmsg_console - 1))
2933 		vc = vc_cons[kmsg_console - 1].d;
2934 
2935 	if (!vc_cons_allocated(fg_console)) {
2936 		/* impossible */
2937 		/* printk("vt_console_print: tty %d not allocated ??\n", currcons+1); */
2938 		goto quit;
2939 	}
2940 
2941 	if (vc->vc_mode != KD_TEXT)
2942 		goto quit;
2943 
2944 	/* undraw cursor first */
2945 	if (con_is_fg(vc))
2946 		hide_cursor(vc);
2947 
2948 	start = (ushort *)vc->vc_pos;
2949 	start_x = vc->vc_x;
2950 	cnt = 0;
2951 	while (count--) {
2952 		c = *b++;
2953 		if (c == 10 || c == 13 || c == 8 || vc->vc_need_wrap) {
2954 			if (cnt && con_is_visible(vc))
2955 				vc->vc_sw->con_putcs(vc, start, cnt, vc->vc_y, start_x);
2956 			cnt = 0;
2957 			if (c == 8) {		/* backspace */
2958 				bs(vc);
2959 				start = (ushort *)vc->vc_pos;
2960 				start_x = vc->vc_x;
2961 				continue;
2962 			}
2963 			if (c != 13)
2964 				lf(vc);
2965 			cr(vc);
2966 			start = (ushort *)vc->vc_pos;
2967 			start_x = vc->vc_x;
2968 			if (c == 10 || c == 13)
2969 				continue;
2970 		}
2971 		vc_uniscr_putc(vc, c);
2972 		scr_writew((vc->vc_attr << 8) + c, (unsigned short *)vc->vc_pos);
2973 		notify_write(vc, c);
2974 		cnt++;
2975 		if (vc->vc_x == vc->vc_cols - 1) {
2976 			vc->vc_need_wrap = 1;
2977 		} else {
2978 			vc->vc_pos += 2;
2979 			vc->vc_x++;
2980 		}
2981 	}
2982 	if (cnt && con_is_visible(vc))
2983 		vc->vc_sw->con_putcs(vc, start, cnt, vc->vc_y, start_x);
2984 	set_cursor(vc);
2985 	notify_update(vc);
2986 
2987 quit:
2988 	spin_unlock(&printing_lock);
2989 }
2990 
2991 static struct tty_driver *vt_console_device(struct console *c, int *index)
2992 {
2993 	*index = c->index ? c->index-1 : fg_console;
2994 	return console_driver;
2995 }
2996 
2997 static struct console vt_console_driver = {
2998 	.name		= "tty",
2999 	.write		= vt_console_print,
3000 	.device		= vt_console_device,
3001 	.unblank	= unblank_screen,
3002 	.flags		= CON_PRINTBUFFER,
3003 	.index		= -1,
3004 };
3005 #endif
3006 
3007 /*
3008  *	Handling of Linux-specific VC ioctls
3009  */
3010 
3011 /*
3012  * Generally a bit racy with respect to console_lock();.
3013  *
3014  * There are some functions which don't need it.
3015  *
3016  * There are some functions which can sleep for arbitrary periods
3017  * (paste_selection) but we don't need the lock there anyway.
3018  *
3019  * set_selection_user has locking, and definitely needs it
3020  */
3021 
3022 int tioclinux(struct tty_struct *tty, unsigned long arg)
3023 {
3024 	char type, data;
3025 	char __user *p = (char __user *)arg;
3026 	int lines;
3027 	int ret;
3028 
3029 	if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
3030 		return -EPERM;
3031 	if (get_user(type, p))
3032 		return -EFAULT;
3033 	ret = 0;
3034 
3035 	switch (type)
3036 	{
3037 		case TIOCL_SETSEL:
3038 			console_lock();
3039 			ret = set_selection_user((struct tiocl_selection
3040 						 __user *)(p+1), tty);
3041 			console_unlock();
3042 			break;
3043 		case TIOCL_PASTESEL:
3044 			ret = paste_selection(tty);
3045 			break;
3046 		case TIOCL_UNBLANKSCREEN:
3047 			console_lock();
3048 			unblank_screen();
3049 			console_unlock();
3050 			break;
3051 		case TIOCL_SELLOADLUT:
3052 			console_lock();
3053 			ret = sel_loadlut(p);
3054 			console_unlock();
3055 			break;
3056 		case TIOCL_GETSHIFTSTATE:
3057 
3058 	/*
3059 	 * Make it possible to react to Shift+Mousebutton.
3060 	 * Note that 'shift_state' is an undocumented
3061 	 * kernel-internal variable; programs not closely
3062 	 * related to the kernel should not use this.
3063 	 */
3064 			data = vt_get_shift_state();
3065 			ret = put_user(data, p);
3066 			break;
3067 		case TIOCL_GETMOUSEREPORTING:
3068 			console_lock();	/* May be overkill */
3069 			data = mouse_reporting();
3070 			console_unlock();
3071 			ret = put_user(data, p);
3072 			break;
3073 		case TIOCL_SETVESABLANK:
3074 			console_lock();
3075 			ret = set_vesa_blanking(p);
3076 			console_unlock();
3077 			break;
3078 		case TIOCL_GETKMSGREDIRECT:
3079 			data = vt_get_kmsg_redirect();
3080 			ret = put_user(data, p);
3081 			break;
3082 		case TIOCL_SETKMSGREDIRECT:
3083 			if (!capable(CAP_SYS_ADMIN)) {
3084 				ret = -EPERM;
3085 			} else {
3086 				if (get_user(data, p+1))
3087 					ret = -EFAULT;
3088 				else
3089 					vt_kmsg_redirect(data);
3090 			}
3091 			break;
3092 		case TIOCL_GETFGCONSOLE:
3093 			/* No locking needed as this is a transiently
3094 			   correct return anyway if the caller hasn't
3095 			   disabled switching */
3096 			ret = fg_console;
3097 			break;
3098 		case TIOCL_SCROLLCONSOLE:
3099 			if (get_user(lines, (s32 __user *)(p+4))) {
3100 				ret = -EFAULT;
3101 			} else {
3102 				/* Need the console lock here. Note that lots
3103 				   of other calls need fixing before the lock
3104 				   is actually useful ! */
3105 				console_lock();
3106 				scrollfront(vc_cons[fg_console].d, lines);
3107 				console_unlock();
3108 				ret = 0;
3109 			}
3110 			break;
3111 		case TIOCL_BLANKSCREEN:	/* until explicitly unblanked, not only poked */
3112 			console_lock();
3113 			ignore_poke = 1;
3114 			do_blank_screen(0);
3115 			console_unlock();
3116 			break;
3117 		case TIOCL_BLANKEDSCREEN:
3118 			ret = console_blanked;
3119 			break;
3120 		default:
3121 			ret = -EINVAL;
3122 			break;
3123 	}
3124 	return ret;
3125 }
3126 
3127 /*
3128  * /dev/ttyN handling
3129  */
3130 
3131 static int con_write(struct tty_struct *tty, const unsigned char *buf, int count)
3132 {
3133 	int	retval;
3134 
3135 	retval = do_con_write(tty, buf, count);
3136 	con_flush_chars(tty);
3137 
3138 	return retval;
3139 }
3140 
3141 static int con_put_char(struct tty_struct *tty, unsigned char ch)
3142 {
3143 	if (in_interrupt())
3144 		return 0;	/* n_r3964 calls put_char() from interrupt context */
3145 	return do_con_write(tty, &ch, 1);
3146 }
3147 
3148 static int con_write_room(struct tty_struct *tty)
3149 {
3150 	if (tty->stopped)
3151 		return 0;
3152 	return 32768;		/* No limit, really; we're not buffering */
3153 }
3154 
3155 static int con_chars_in_buffer(struct tty_struct *tty)
3156 {
3157 	return 0;		/* we're not buffering */
3158 }
3159 
3160 /*
3161  * con_throttle and con_unthrottle are only used for
3162  * paste_selection(), which has to stuff in a large number of
3163  * characters...
3164  */
3165 static void con_throttle(struct tty_struct *tty)
3166 {
3167 }
3168 
3169 static void con_unthrottle(struct tty_struct *tty)
3170 {
3171 	struct vc_data *vc = tty->driver_data;
3172 
3173 	wake_up_interruptible(&vc->paste_wait);
3174 }
3175 
3176 /*
3177  * Turn the Scroll-Lock LED on when the tty is stopped
3178  */
3179 static void con_stop(struct tty_struct *tty)
3180 {
3181 	int console_num;
3182 	if (!tty)
3183 		return;
3184 	console_num = tty->index;
3185 	if (!vc_cons_allocated(console_num))
3186 		return;
3187 	vt_kbd_con_stop(console_num);
3188 }
3189 
3190 /*
3191  * Turn the Scroll-Lock LED off when the console is started
3192  */
3193 static void con_start(struct tty_struct *tty)
3194 {
3195 	int console_num;
3196 	if (!tty)
3197 		return;
3198 	console_num = tty->index;
3199 	if (!vc_cons_allocated(console_num))
3200 		return;
3201 	vt_kbd_con_start(console_num);
3202 }
3203 
3204 static void con_flush_chars(struct tty_struct *tty)
3205 {
3206 	struct vc_data *vc;
3207 
3208 	if (in_interrupt())	/* from flush_to_ldisc */
3209 		return;
3210 
3211 	/* if we race with con_close(), vt may be null */
3212 	console_lock();
3213 	vc = tty->driver_data;
3214 	if (vc)
3215 		set_cursor(vc);
3216 	console_unlock();
3217 }
3218 
3219 /*
3220  * Allocate the console screen memory.
3221  */
3222 static int con_install(struct tty_driver *driver, struct tty_struct *tty)
3223 {
3224 	unsigned int currcons = tty->index;
3225 	struct vc_data *vc;
3226 	int ret;
3227 
3228 	console_lock();
3229 	ret = vc_allocate(currcons);
3230 	if (ret)
3231 		goto unlock;
3232 
3233 	vc = vc_cons[currcons].d;
3234 
3235 	/* Still being freed */
3236 	if (vc->port.tty) {
3237 		ret = -ERESTARTSYS;
3238 		goto unlock;
3239 	}
3240 
3241 	ret = tty_port_install(&vc->port, driver, tty);
3242 	if (ret)
3243 		goto unlock;
3244 
3245 	tty->driver_data = vc;
3246 	vc->port.tty = tty;
3247 
3248 	if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
3249 		tty->winsize.ws_row = vc_cons[currcons].d->vc_rows;
3250 		tty->winsize.ws_col = vc_cons[currcons].d->vc_cols;
3251 	}
3252 	if (vc->vc_utf)
3253 		tty->termios.c_iflag |= IUTF8;
3254 	else
3255 		tty->termios.c_iflag &= ~IUTF8;
3256 unlock:
3257 	console_unlock();
3258 	return ret;
3259 }
3260 
3261 static int con_open(struct tty_struct *tty, struct file *filp)
3262 {
3263 	/* everything done in install */
3264 	return 0;
3265 }
3266 
3267 
3268 static void con_close(struct tty_struct *tty, struct file *filp)
3269 {
3270 	/* Nothing to do - we defer to shutdown */
3271 }
3272 
3273 static void con_shutdown(struct tty_struct *tty)
3274 {
3275 	struct vc_data *vc = tty->driver_data;
3276 	BUG_ON(vc == NULL);
3277 	console_lock();
3278 	vc->port.tty = NULL;
3279 	console_unlock();
3280 }
3281 
3282 static int default_color           = 7; /* white */
3283 static int default_italic_color    = 2; // green (ASCII)
3284 static int default_underline_color = 3; // cyan (ASCII)
3285 module_param_named(color, default_color, int, S_IRUGO | S_IWUSR);
3286 module_param_named(italic, default_italic_color, int, S_IRUGO | S_IWUSR);
3287 module_param_named(underline, default_underline_color, int, S_IRUGO | S_IWUSR);
3288 
3289 static void vc_init(struct vc_data *vc, unsigned int rows,
3290 		    unsigned int cols, int do_clear)
3291 {
3292 	int j, k ;
3293 
3294 	vc->vc_cols = cols;
3295 	vc->vc_rows = rows;
3296 	vc->vc_size_row = cols << 1;
3297 	vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
3298 
3299 	set_origin(vc);
3300 	vc->vc_pos = vc->vc_origin;
3301 	reset_vc(vc);
3302 	for (j=k=0; j<16; j++) {
3303 		vc->vc_palette[k++] = default_red[j] ;
3304 		vc->vc_palette[k++] = default_grn[j] ;
3305 		vc->vc_palette[k++] = default_blu[j] ;
3306 	}
3307 	vc->vc_def_color       = default_color;
3308 	vc->vc_ulcolor         = default_underline_color;
3309 	vc->vc_itcolor         = default_italic_color;
3310 	vc->vc_halfcolor       = 0x08;   /* grey */
3311 	init_waitqueue_head(&vc->paste_wait);
3312 	reset_terminal(vc, do_clear);
3313 }
3314 
3315 /*
3316  * This routine initializes console interrupts, and does nothing
3317  * else. If you want the screen to clear, call tty_write with
3318  * the appropriate escape-sequence.
3319  */
3320 
3321 static int __init con_init(void)
3322 {
3323 	const char *display_desc = NULL;
3324 	struct vc_data *vc;
3325 	unsigned int currcons = 0, i;
3326 
3327 	console_lock();
3328 
3329 	if (conswitchp)
3330 		display_desc = conswitchp->con_startup();
3331 	if (!display_desc) {
3332 		fg_console = 0;
3333 		console_unlock();
3334 		return 0;
3335 	}
3336 
3337 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3338 		struct con_driver *con_driver = &registered_con_driver[i];
3339 
3340 		if (con_driver->con == NULL) {
3341 			con_driver->con = conswitchp;
3342 			con_driver->desc = display_desc;
3343 			con_driver->flag = CON_DRIVER_FLAG_INIT;
3344 			con_driver->first = 0;
3345 			con_driver->last = MAX_NR_CONSOLES - 1;
3346 			break;
3347 		}
3348 	}
3349 
3350 	for (i = 0; i < MAX_NR_CONSOLES; i++)
3351 		con_driver_map[i] = conswitchp;
3352 
3353 	if (blankinterval) {
3354 		blank_state = blank_normal_wait;
3355 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3356 	}
3357 
3358 	for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) {
3359 		vc_cons[currcons].d = vc = kzalloc(sizeof(struct vc_data), GFP_NOWAIT);
3360 		INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
3361 		tty_port_init(&vc->port);
3362 		visual_init(vc, currcons, 1);
3363 		vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_NOWAIT);
3364 		vc_init(vc, vc->vc_rows, vc->vc_cols,
3365 			currcons || !vc->vc_sw->con_save_screen);
3366 	}
3367 	currcons = fg_console = 0;
3368 	master_display_fg = vc = vc_cons[currcons].d;
3369 	set_origin(vc);
3370 	save_screen(vc);
3371 	gotoxy(vc, vc->vc_x, vc->vc_y);
3372 	csi_J(vc, 0);
3373 	update_screen(vc);
3374 	pr_info("Console: %s %s %dx%d\n",
3375 		vc->vc_can_do_color ? "colour" : "mono",
3376 		display_desc, vc->vc_cols, vc->vc_rows);
3377 	printable = 1;
3378 
3379 	console_unlock();
3380 
3381 #ifdef CONFIG_VT_CONSOLE
3382 	register_console(&vt_console_driver);
3383 #endif
3384 	return 0;
3385 }
3386 console_initcall(con_init);
3387 
3388 static const struct tty_operations con_ops = {
3389 	.install = con_install,
3390 	.open = con_open,
3391 	.close = con_close,
3392 	.write = con_write,
3393 	.write_room = con_write_room,
3394 	.put_char = con_put_char,
3395 	.flush_chars = con_flush_chars,
3396 	.chars_in_buffer = con_chars_in_buffer,
3397 	.ioctl = vt_ioctl,
3398 #ifdef CONFIG_COMPAT
3399 	.compat_ioctl = vt_compat_ioctl,
3400 #endif
3401 	.stop = con_stop,
3402 	.start = con_start,
3403 	.throttle = con_throttle,
3404 	.unthrottle = con_unthrottle,
3405 	.resize = vt_resize,
3406 	.shutdown = con_shutdown
3407 };
3408 
3409 static struct cdev vc0_cdev;
3410 
3411 static ssize_t show_tty_active(struct device *dev,
3412 				struct device_attribute *attr, char *buf)
3413 {
3414 	return sprintf(buf, "tty%d\n", fg_console + 1);
3415 }
3416 static DEVICE_ATTR(active, S_IRUGO, show_tty_active, NULL);
3417 
3418 static struct attribute *vt_dev_attrs[] = {
3419 	&dev_attr_active.attr,
3420 	NULL
3421 };
3422 
3423 ATTRIBUTE_GROUPS(vt_dev);
3424 
3425 int __init vty_init(const struct file_operations *console_fops)
3426 {
3427 	cdev_init(&vc0_cdev, console_fops);
3428 	if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
3429 	    register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
3430 		panic("Couldn't register /dev/tty0 driver\n");
3431 	tty0dev = device_create_with_groups(tty_class, NULL,
3432 					    MKDEV(TTY_MAJOR, 0), NULL,
3433 					    vt_dev_groups, "tty0");
3434 	if (IS_ERR(tty0dev))
3435 		tty0dev = NULL;
3436 
3437 	vcs_init();
3438 
3439 	console_driver = alloc_tty_driver(MAX_NR_CONSOLES);
3440 	if (!console_driver)
3441 		panic("Couldn't allocate console driver\n");
3442 
3443 	console_driver->name = "tty";
3444 	console_driver->name_base = 1;
3445 	console_driver->major = TTY_MAJOR;
3446 	console_driver->minor_start = 1;
3447 	console_driver->type = TTY_DRIVER_TYPE_CONSOLE;
3448 	console_driver->init_termios = tty_std_termios;
3449 	if (default_utf8)
3450 		console_driver->init_termios.c_iflag |= IUTF8;
3451 	console_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS;
3452 	tty_set_operations(console_driver, &con_ops);
3453 	if (tty_register_driver(console_driver))
3454 		panic("Couldn't register console driver\n");
3455 	kbd_init();
3456 	console_map_init();
3457 #ifdef CONFIG_MDA_CONSOLE
3458 	mda_console_init();
3459 #endif
3460 	return 0;
3461 }
3462 
3463 #ifndef VT_SINGLE_DRIVER
3464 
3465 static struct class *vtconsole_class;
3466 
3467 static int do_bind_con_driver(const struct consw *csw, int first, int last,
3468 			   int deflt)
3469 {
3470 	struct module *owner = csw->owner;
3471 	const char *desc = NULL;
3472 	struct con_driver *con_driver;
3473 	int i, j = -1, k = -1, retval = -ENODEV;
3474 
3475 	if (!try_module_get(owner))
3476 		return -ENODEV;
3477 
3478 	WARN_CONSOLE_UNLOCKED();
3479 
3480 	/* check if driver is registered */
3481 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3482 		con_driver = &registered_con_driver[i];
3483 
3484 		if (con_driver->con == csw) {
3485 			desc = con_driver->desc;
3486 			retval = 0;
3487 			break;
3488 		}
3489 	}
3490 
3491 	if (retval)
3492 		goto err;
3493 
3494 	if (!(con_driver->flag & CON_DRIVER_FLAG_INIT)) {
3495 		csw->con_startup();
3496 		con_driver->flag |= CON_DRIVER_FLAG_INIT;
3497 	}
3498 
3499 	if (deflt) {
3500 		if (conswitchp)
3501 			module_put(conswitchp->owner);
3502 
3503 		__module_get(owner);
3504 		conswitchp = csw;
3505 	}
3506 
3507 	first = max(first, con_driver->first);
3508 	last = min(last, con_driver->last);
3509 
3510 	for (i = first; i <= last; i++) {
3511 		int old_was_color;
3512 		struct vc_data *vc = vc_cons[i].d;
3513 
3514 		if (con_driver_map[i])
3515 			module_put(con_driver_map[i]->owner);
3516 		__module_get(owner);
3517 		con_driver_map[i] = csw;
3518 
3519 		if (!vc || !vc->vc_sw)
3520 			continue;
3521 
3522 		j = i;
3523 
3524 		if (con_is_visible(vc)) {
3525 			k = i;
3526 			save_screen(vc);
3527 		}
3528 
3529 		old_was_color = vc->vc_can_do_color;
3530 		vc->vc_sw->con_deinit(vc);
3531 		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
3532 		visual_init(vc, i, 0);
3533 		set_origin(vc);
3534 		update_attr(vc);
3535 
3536 		/* If the console changed between mono <-> color, then
3537 		 * the attributes in the screenbuf will be wrong.  The
3538 		 * following resets all attributes to something sane.
3539 		 */
3540 		if (old_was_color != vc->vc_can_do_color)
3541 			clear_buffer_attributes(vc);
3542 	}
3543 
3544 	pr_info("Console: switching ");
3545 	if (!deflt)
3546 		pr_cont("consoles %d-%d ", first + 1, last + 1);
3547 	if (j >= 0) {
3548 		struct vc_data *vc = vc_cons[j].d;
3549 
3550 		pr_cont("to %s %s %dx%d\n",
3551 			vc->vc_can_do_color ? "colour" : "mono",
3552 			desc, vc->vc_cols, vc->vc_rows);
3553 
3554 		if (k >= 0) {
3555 			vc = vc_cons[k].d;
3556 			update_screen(vc);
3557 		}
3558 	} else {
3559 		pr_cont("to %s\n", desc);
3560 	}
3561 
3562 	retval = 0;
3563 err:
3564 	module_put(owner);
3565 	return retval;
3566 };
3567 
3568 
3569 #ifdef CONFIG_VT_HW_CONSOLE_BINDING
3570 /* unlocked version of unbind_con_driver() */
3571 int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
3572 {
3573 	struct module *owner = csw->owner;
3574 	const struct consw *defcsw = NULL;
3575 	struct con_driver *con_driver = NULL, *con_back = NULL;
3576 	int i, retval = -ENODEV;
3577 
3578 	if (!try_module_get(owner))
3579 		return -ENODEV;
3580 
3581 	WARN_CONSOLE_UNLOCKED();
3582 
3583 	/* check if driver is registered and if it is unbindable */
3584 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3585 		con_driver = &registered_con_driver[i];
3586 
3587 		if (con_driver->con == csw &&
3588 		    con_driver->flag & CON_DRIVER_FLAG_MODULE) {
3589 			retval = 0;
3590 			break;
3591 		}
3592 	}
3593 
3594 	if (retval)
3595 		goto err;
3596 
3597 	retval = -ENODEV;
3598 
3599 	/* check if backup driver exists */
3600 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3601 		con_back = &registered_con_driver[i];
3602 
3603 		if (con_back->con && con_back->con != csw) {
3604 			defcsw = con_back->con;
3605 			retval = 0;
3606 			break;
3607 		}
3608 	}
3609 
3610 	if (retval)
3611 		goto err;
3612 
3613 	if (!con_is_bound(csw))
3614 		goto err;
3615 
3616 	first = max(first, con_driver->first);
3617 	last = min(last, con_driver->last);
3618 
3619 	for (i = first; i <= last; i++) {
3620 		if (con_driver_map[i] == csw) {
3621 			module_put(csw->owner);
3622 			con_driver_map[i] = NULL;
3623 		}
3624 	}
3625 
3626 	if (!con_is_bound(defcsw)) {
3627 		const struct consw *defconsw = conswitchp;
3628 
3629 		defcsw->con_startup();
3630 		con_back->flag |= CON_DRIVER_FLAG_INIT;
3631 		/*
3632 		 * vgacon may change the default driver to point
3633 		 * to dummycon, we restore it here...
3634 		 */
3635 		conswitchp = defconsw;
3636 	}
3637 
3638 	if (!con_is_bound(csw))
3639 		con_driver->flag &= ~CON_DRIVER_FLAG_INIT;
3640 
3641 	/* ignore return value, binding should not fail */
3642 	do_bind_con_driver(defcsw, first, last, deflt);
3643 err:
3644 	module_put(owner);
3645 	return retval;
3646 
3647 }
3648 EXPORT_SYMBOL_GPL(do_unbind_con_driver);
3649 
3650 static int vt_bind(struct con_driver *con)
3651 {
3652 	const struct consw *defcsw = NULL, *csw = NULL;
3653 	int i, more = 1, first = -1, last = -1, deflt = 0;
3654 
3655  	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3656 		goto err;
3657 
3658 	csw = con->con;
3659 
3660 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3661 		struct con_driver *con = &registered_con_driver[i];
3662 
3663 		if (con->con && !(con->flag & CON_DRIVER_FLAG_MODULE)) {
3664 			defcsw = con->con;
3665 			break;
3666 		}
3667 	}
3668 
3669 	if (!defcsw)
3670 		goto err;
3671 
3672 	while (more) {
3673 		more = 0;
3674 
3675 		for (i = con->first; i <= con->last; i++) {
3676 			if (con_driver_map[i] == defcsw) {
3677 				if (first == -1)
3678 					first = i;
3679 				last = i;
3680 				more = 1;
3681 			} else if (first != -1)
3682 				break;
3683 		}
3684 
3685 		if (first == 0 && last == MAX_NR_CONSOLES -1)
3686 			deflt = 1;
3687 
3688 		if (first != -1)
3689 			do_bind_con_driver(csw, first, last, deflt);
3690 
3691 		first = -1;
3692 		last = -1;
3693 		deflt = 0;
3694 	}
3695 
3696 err:
3697 	return 0;
3698 }
3699 
3700 static int vt_unbind(struct con_driver *con)
3701 {
3702 	const struct consw *csw = NULL;
3703 	int i, more = 1, first = -1, last = -1, deflt = 0;
3704 	int ret;
3705 
3706  	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3707 		goto err;
3708 
3709 	csw = con->con;
3710 
3711 	while (more) {
3712 		more = 0;
3713 
3714 		for (i = con->first; i <= con->last; i++) {
3715 			if (con_driver_map[i] == csw) {
3716 				if (first == -1)
3717 					first = i;
3718 				last = i;
3719 				more = 1;
3720 			} else if (first != -1)
3721 				break;
3722 		}
3723 
3724 		if (first == 0 && last == MAX_NR_CONSOLES -1)
3725 			deflt = 1;
3726 
3727 		if (first != -1) {
3728 			ret = do_unbind_con_driver(csw, first, last, deflt);
3729 			if (ret != 0)
3730 				return ret;
3731 		}
3732 
3733 		first = -1;
3734 		last = -1;
3735 		deflt = 0;
3736 	}
3737 
3738 err:
3739 	return 0;
3740 }
3741 #else
3742 static inline int vt_bind(struct con_driver *con)
3743 {
3744 	return 0;
3745 }
3746 static inline int vt_unbind(struct con_driver *con)
3747 {
3748 	return 0;
3749 }
3750 #endif /* CONFIG_VT_HW_CONSOLE_BINDING */
3751 
3752 static ssize_t store_bind(struct device *dev, struct device_attribute *attr,
3753 			  const char *buf, size_t count)
3754 {
3755 	struct con_driver *con = dev_get_drvdata(dev);
3756 	int bind = simple_strtoul(buf, NULL, 0);
3757 
3758 	console_lock();
3759 
3760 	if (bind)
3761 		vt_bind(con);
3762 	else
3763 		vt_unbind(con);
3764 
3765 	console_unlock();
3766 
3767 	return count;
3768 }
3769 
3770 static ssize_t show_bind(struct device *dev, struct device_attribute *attr,
3771 			 char *buf)
3772 {
3773 	struct con_driver *con = dev_get_drvdata(dev);
3774 	int bind = con_is_bound(con->con);
3775 
3776 	return snprintf(buf, PAGE_SIZE, "%i\n", bind);
3777 }
3778 
3779 static ssize_t show_name(struct device *dev, struct device_attribute *attr,
3780 			 char *buf)
3781 {
3782 	struct con_driver *con = dev_get_drvdata(dev);
3783 
3784 	return snprintf(buf, PAGE_SIZE, "%s %s\n",
3785 			(con->flag & CON_DRIVER_FLAG_MODULE) ? "(M)" : "(S)",
3786 			 con->desc);
3787 
3788 }
3789 
3790 static DEVICE_ATTR(bind, S_IRUGO|S_IWUSR, show_bind, store_bind);
3791 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
3792 
3793 static struct attribute *con_dev_attrs[] = {
3794 	&dev_attr_bind.attr,
3795 	&dev_attr_name.attr,
3796 	NULL
3797 };
3798 
3799 ATTRIBUTE_GROUPS(con_dev);
3800 
3801 static int vtconsole_init_device(struct con_driver *con)
3802 {
3803 	con->flag |= CON_DRIVER_FLAG_ATTR;
3804 	return 0;
3805 }
3806 
3807 static void vtconsole_deinit_device(struct con_driver *con)
3808 {
3809 	con->flag &= ~CON_DRIVER_FLAG_ATTR;
3810 }
3811 
3812 /**
3813  * con_is_bound - checks if driver is bound to the console
3814  * @csw: console driver
3815  *
3816  * RETURNS: zero if unbound, nonzero if bound
3817  *
3818  * Drivers can call this and if zero, they should release
3819  * all resources allocated on con_startup()
3820  */
3821 int con_is_bound(const struct consw *csw)
3822 {
3823 	int i, bound = 0;
3824 
3825 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
3826 		if (con_driver_map[i] == csw) {
3827 			bound = 1;
3828 			break;
3829 		}
3830 	}
3831 
3832 	return bound;
3833 }
3834 EXPORT_SYMBOL(con_is_bound);
3835 
3836 /**
3837  * con_debug_enter - prepare the console for the kernel debugger
3838  * @sw: console driver
3839  *
3840  * Called when the console is taken over by the kernel debugger, this
3841  * function needs to save the current console state, then put the console
3842  * into a state suitable for the kernel debugger.
3843  *
3844  * RETURNS:
3845  * Zero on success, nonzero if a failure occurred when trying to prepare
3846  * the console for the debugger.
3847  */
3848 int con_debug_enter(struct vc_data *vc)
3849 {
3850 	int ret = 0;
3851 
3852 	saved_fg_console = fg_console;
3853 	saved_last_console = last_console;
3854 	saved_want_console = want_console;
3855 	saved_vc_mode = vc->vc_mode;
3856 	saved_console_blanked = console_blanked;
3857 	vc->vc_mode = KD_TEXT;
3858 	console_blanked = 0;
3859 	if (vc->vc_sw->con_debug_enter)
3860 		ret = vc->vc_sw->con_debug_enter(vc);
3861 #ifdef CONFIG_KGDB_KDB
3862 	/* Set the initial LINES variable if it is not already set */
3863 	if (vc->vc_rows < 999) {
3864 		int linecount;
3865 		char lns[4];
3866 		const char *setargs[3] = {
3867 			"set",
3868 			"LINES",
3869 			lns,
3870 		};
3871 		if (kdbgetintenv(setargs[0], &linecount)) {
3872 			snprintf(lns, 4, "%i", vc->vc_rows);
3873 			kdb_set(2, setargs);
3874 		}
3875 	}
3876 	if (vc->vc_cols < 999) {
3877 		int colcount;
3878 		char cols[4];
3879 		const char *setargs[3] = {
3880 			"set",
3881 			"COLUMNS",
3882 			cols,
3883 		};
3884 		if (kdbgetintenv(setargs[0], &colcount)) {
3885 			snprintf(cols, 4, "%i", vc->vc_cols);
3886 			kdb_set(2, setargs);
3887 		}
3888 	}
3889 #endif /* CONFIG_KGDB_KDB */
3890 	return ret;
3891 }
3892 EXPORT_SYMBOL_GPL(con_debug_enter);
3893 
3894 /**
3895  * con_debug_leave - restore console state
3896  * @sw: console driver
3897  *
3898  * Restore the console state to what it was before the kernel debugger
3899  * was invoked.
3900  *
3901  * RETURNS:
3902  * Zero on success, nonzero if a failure occurred when trying to restore
3903  * the console.
3904  */
3905 int con_debug_leave(void)
3906 {
3907 	struct vc_data *vc;
3908 	int ret = 0;
3909 
3910 	fg_console = saved_fg_console;
3911 	last_console = saved_last_console;
3912 	want_console = saved_want_console;
3913 	console_blanked = saved_console_blanked;
3914 	vc_cons[fg_console].d->vc_mode = saved_vc_mode;
3915 
3916 	vc = vc_cons[fg_console].d;
3917 	if (vc->vc_sw->con_debug_leave)
3918 		ret = vc->vc_sw->con_debug_leave(vc);
3919 	return ret;
3920 }
3921 EXPORT_SYMBOL_GPL(con_debug_leave);
3922 
3923 static int do_register_con_driver(const struct consw *csw, int first, int last)
3924 {
3925 	struct module *owner = csw->owner;
3926 	struct con_driver *con_driver;
3927 	const char *desc;
3928 	int i, retval;
3929 
3930 	WARN_CONSOLE_UNLOCKED();
3931 
3932 	if (!try_module_get(owner))
3933 		return -ENODEV;
3934 
3935 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3936 		con_driver = &registered_con_driver[i];
3937 
3938 		/* already registered */
3939 		if (con_driver->con == csw) {
3940 			retval = -EBUSY;
3941 			goto err;
3942 		}
3943 	}
3944 
3945 	desc = csw->con_startup();
3946 	if (!desc) {
3947 		retval = -ENODEV;
3948 		goto err;
3949 	}
3950 
3951 	retval = -EINVAL;
3952 
3953 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3954 		con_driver = &registered_con_driver[i];
3955 
3956 		if (con_driver->con == NULL &&
3957 		    !(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE)) {
3958 			con_driver->con = csw;
3959 			con_driver->desc = desc;
3960 			con_driver->node = i;
3961 			con_driver->flag = CON_DRIVER_FLAG_MODULE |
3962 			                   CON_DRIVER_FLAG_INIT;
3963 			con_driver->first = first;
3964 			con_driver->last = last;
3965 			retval = 0;
3966 			break;
3967 		}
3968 	}
3969 
3970 	if (retval)
3971 		goto err;
3972 
3973 	con_driver->dev =
3974 		device_create_with_groups(vtconsole_class, NULL,
3975 					  MKDEV(0, con_driver->node),
3976 					  con_driver, con_dev_groups,
3977 					  "vtcon%i", con_driver->node);
3978 	if (IS_ERR(con_driver->dev)) {
3979 		pr_warn("Unable to create device for %s; errno = %ld\n",
3980 			con_driver->desc, PTR_ERR(con_driver->dev));
3981 		con_driver->dev = NULL;
3982 	} else {
3983 		vtconsole_init_device(con_driver);
3984 	}
3985 
3986 err:
3987 	module_put(owner);
3988 	return retval;
3989 }
3990 
3991 
3992 /**
3993  * do_unregister_con_driver - unregister console driver from console layer
3994  * @csw: console driver
3995  *
3996  * DESCRIPTION: All drivers that registers to the console layer must
3997  * call this function upon exit, or if the console driver is in a state
3998  * where it won't be able to handle console services, such as the
3999  * framebuffer console without loaded framebuffer drivers.
4000  *
4001  * The driver must unbind first prior to unregistration.
4002  */
4003 int do_unregister_con_driver(const struct consw *csw)
4004 {
4005 	int i;
4006 
4007 	/* cannot unregister a bound driver */
4008 	if (con_is_bound(csw))
4009 		return -EBUSY;
4010 
4011 	if (csw == conswitchp)
4012 		return -EINVAL;
4013 
4014 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4015 		struct con_driver *con_driver = &registered_con_driver[i];
4016 
4017 		if (con_driver->con == csw) {
4018 			/*
4019 			 * Defer the removal of the sysfs entries since that
4020 			 * will acquire the kernfs s_active lock and we can't
4021 			 * acquire this lock while holding the console lock:
4022 			 * the unbind sysfs entry imposes already the opposite
4023 			 * order. Reset con already here to prevent any later
4024 			 * lookup to succeed and mark this slot as zombie, so
4025 			 * it won't get reused until we complete the removal
4026 			 * in the deferred work.
4027 			 */
4028 			con_driver->con = NULL;
4029 			con_driver->flag = CON_DRIVER_FLAG_ZOMBIE;
4030 			schedule_work(&con_driver_unregister_work);
4031 
4032 			return 0;
4033 		}
4034 	}
4035 
4036 	return -ENODEV;
4037 }
4038 EXPORT_SYMBOL_GPL(do_unregister_con_driver);
4039 
4040 static void con_driver_unregister_callback(struct work_struct *ignored)
4041 {
4042 	int i;
4043 
4044 	console_lock();
4045 
4046 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4047 		struct con_driver *con_driver = &registered_con_driver[i];
4048 
4049 		if (!(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE))
4050 			continue;
4051 
4052 		console_unlock();
4053 
4054 		vtconsole_deinit_device(con_driver);
4055 		device_destroy(vtconsole_class, MKDEV(0, con_driver->node));
4056 
4057 		console_lock();
4058 
4059 		if (WARN_ON_ONCE(con_driver->con))
4060 			con_driver->con = NULL;
4061 		con_driver->desc = NULL;
4062 		con_driver->dev = NULL;
4063 		con_driver->node = 0;
4064 		WARN_ON_ONCE(con_driver->flag != CON_DRIVER_FLAG_ZOMBIE);
4065 		con_driver->flag = 0;
4066 		con_driver->first = 0;
4067 		con_driver->last = 0;
4068 	}
4069 
4070 	console_unlock();
4071 }
4072 
4073 /*
4074  *	If we support more console drivers, this function is used
4075  *	when a driver wants to take over some existing consoles
4076  *	and become default driver for newly opened ones.
4077  *
4078  *	do_take_over_console is basically a register followed by unbind
4079  */
4080 int do_take_over_console(const struct consw *csw, int first, int last, int deflt)
4081 {
4082 	int err;
4083 
4084 	err = do_register_con_driver(csw, first, last);
4085 	/*
4086 	 * If we get an busy error we still want to bind the console driver
4087 	 * and return success, as we may have unbound the console driver
4088 	 * but not unregistered it.
4089 	 */
4090 	if (err == -EBUSY)
4091 		err = 0;
4092 	if (!err)
4093 		do_bind_con_driver(csw, first, last, deflt);
4094 
4095 	return err;
4096 }
4097 EXPORT_SYMBOL_GPL(do_take_over_console);
4098 
4099 
4100 /*
4101  * give_up_console is a wrapper to unregister_con_driver. It will only
4102  * work if driver is fully unbound.
4103  */
4104 void give_up_console(const struct consw *csw)
4105 {
4106 	console_lock();
4107 	do_unregister_con_driver(csw);
4108 	console_unlock();
4109 }
4110 
4111 static int __init vtconsole_class_init(void)
4112 {
4113 	int i;
4114 
4115 	vtconsole_class = class_create(THIS_MODULE, "vtconsole");
4116 	if (IS_ERR(vtconsole_class)) {
4117 		pr_warn("Unable to create vt console class; errno = %ld\n",
4118 			PTR_ERR(vtconsole_class));
4119 		vtconsole_class = NULL;
4120 	}
4121 
4122 	/* Add system drivers to sysfs */
4123 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4124 		struct con_driver *con = &registered_con_driver[i];
4125 
4126 		if (con->con && !con->dev) {
4127 			con->dev =
4128 				device_create_with_groups(vtconsole_class, NULL,
4129 							  MKDEV(0, con->node),
4130 							  con, con_dev_groups,
4131 							  "vtcon%i", con->node);
4132 
4133 			if (IS_ERR(con->dev)) {
4134 				pr_warn("Unable to create device for %s; errno = %ld\n",
4135 					con->desc, PTR_ERR(con->dev));
4136 				con->dev = NULL;
4137 			} else {
4138 				vtconsole_init_device(con);
4139 			}
4140 		}
4141 	}
4142 
4143 	return 0;
4144 }
4145 postcore_initcall(vtconsole_class_init);
4146 
4147 #endif
4148 
4149 /*
4150  *	Screen blanking
4151  */
4152 
4153 static int set_vesa_blanking(char __user *p)
4154 {
4155 	unsigned int mode;
4156 
4157 	if (get_user(mode, p + 1))
4158 		return -EFAULT;
4159 
4160 	vesa_blank_mode = (mode < 4) ? mode : 0;
4161 	return 0;
4162 }
4163 
4164 void do_blank_screen(int entering_gfx)
4165 {
4166 	struct vc_data *vc = vc_cons[fg_console].d;
4167 	int i;
4168 
4169 	WARN_CONSOLE_UNLOCKED();
4170 
4171 	if (console_blanked) {
4172 		if (blank_state == blank_vesa_wait) {
4173 			blank_state = blank_off;
4174 			vc->vc_sw->con_blank(vc, vesa_blank_mode + 1, 0);
4175 		}
4176 		return;
4177 	}
4178 
4179 	/* entering graphics mode? */
4180 	if (entering_gfx) {
4181 		hide_cursor(vc);
4182 		save_screen(vc);
4183 		vc->vc_sw->con_blank(vc, -1, 1);
4184 		console_blanked = fg_console + 1;
4185 		blank_state = blank_off;
4186 		set_origin(vc);
4187 		return;
4188 	}
4189 
4190 	blank_state = blank_off;
4191 
4192 	/* don't blank graphics */
4193 	if (vc->vc_mode != KD_TEXT) {
4194 		console_blanked = fg_console + 1;
4195 		return;
4196 	}
4197 
4198 	hide_cursor(vc);
4199 	del_timer_sync(&console_timer);
4200 	blank_timer_expired = 0;
4201 
4202 	save_screen(vc);
4203 	/* In case we need to reset origin, blanking hook returns 1 */
4204 	i = vc->vc_sw->con_blank(vc, vesa_off_interval ? 1 : (vesa_blank_mode + 1), 0);
4205 	console_blanked = fg_console + 1;
4206 	if (i)
4207 		set_origin(vc);
4208 
4209 	if (console_blank_hook && console_blank_hook(1))
4210 		return;
4211 
4212 	if (vesa_off_interval && vesa_blank_mode) {
4213 		blank_state = blank_vesa_wait;
4214 		mod_timer(&console_timer, jiffies + vesa_off_interval);
4215 	}
4216 	vt_event_post(VT_EVENT_BLANK, vc->vc_num, vc->vc_num);
4217 }
4218 EXPORT_SYMBOL(do_blank_screen);
4219 
4220 /*
4221  * Called by timer as well as from vt_console_driver
4222  */
4223 void do_unblank_screen(int leaving_gfx)
4224 {
4225 	struct vc_data *vc;
4226 
4227 	/* This should now always be called from a "sane" (read: can schedule)
4228 	 * context for the sake of the low level drivers, except in the special
4229 	 * case of oops_in_progress
4230 	 */
4231 	if (!oops_in_progress)
4232 		might_sleep();
4233 
4234 	WARN_CONSOLE_UNLOCKED();
4235 
4236 	ignore_poke = 0;
4237 	if (!console_blanked)
4238 		return;
4239 	if (!vc_cons_allocated(fg_console)) {
4240 		/* impossible */
4241 		pr_warn("unblank_screen: tty %d not allocated ??\n",
4242 			fg_console + 1);
4243 		return;
4244 	}
4245 	vc = vc_cons[fg_console].d;
4246 	if (vc->vc_mode != KD_TEXT)
4247 		return; /* but leave console_blanked != 0 */
4248 
4249 	if (blankinterval) {
4250 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4251 		blank_state = blank_normal_wait;
4252 	}
4253 
4254 	console_blanked = 0;
4255 	if (vc->vc_sw->con_blank(vc, 0, leaving_gfx))
4256 		/* Low-level driver cannot restore -> do it ourselves */
4257 		update_screen(vc);
4258 	if (console_blank_hook)
4259 		console_blank_hook(0);
4260 	set_palette(vc);
4261 	set_cursor(vc);
4262 	vt_event_post(VT_EVENT_UNBLANK, vc->vc_num, vc->vc_num);
4263 }
4264 EXPORT_SYMBOL(do_unblank_screen);
4265 
4266 /*
4267  * This is called by the outside world to cause a forced unblank, mostly for
4268  * oopses. Currently, I just call do_unblank_screen(0), but we could eventually
4269  * call it with 1 as an argument and so force a mode restore... that may kill
4270  * X or at least garbage the screen but would also make the Oops visible...
4271  */
4272 void unblank_screen(void)
4273 {
4274 	do_unblank_screen(0);
4275 }
4276 
4277 /*
4278  * We defer the timer blanking to work queue so it can take the console mutex
4279  * (console operations can still happen at irq time, but only from printk which
4280  * has the console mutex. Not perfect yet, but better than no locking
4281  */
4282 static void blank_screen_t(struct timer_list *unused)
4283 {
4284 	blank_timer_expired = 1;
4285 	schedule_work(&console_work);
4286 }
4287 
4288 void poke_blanked_console(void)
4289 {
4290 	WARN_CONSOLE_UNLOCKED();
4291 
4292 	/* Add this so we quickly catch whoever might call us in a non
4293 	 * safe context. Nowadays, unblank_screen() isn't to be called in
4294 	 * atomic contexts and is allowed to schedule (with the special case
4295 	 * of oops_in_progress, but that isn't of any concern for this
4296 	 * function. --BenH.
4297 	 */
4298 	might_sleep();
4299 
4300 	/* This isn't perfectly race free, but a race here would be mostly harmless,
4301 	 * at worse, we'll do a spurrious blank and it's unlikely
4302 	 */
4303 	del_timer(&console_timer);
4304 	blank_timer_expired = 0;
4305 
4306 	if (ignore_poke || !vc_cons[fg_console].d || vc_cons[fg_console].d->vc_mode == KD_GRAPHICS)
4307 		return;
4308 	if (console_blanked)
4309 		unblank_screen();
4310 	else if (blankinterval) {
4311 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4312 		blank_state = blank_normal_wait;
4313 	}
4314 }
4315 
4316 /*
4317  *	Palettes
4318  */
4319 
4320 static void set_palette(struct vc_data *vc)
4321 {
4322 	WARN_CONSOLE_UNLOCKED();
4323 
4324 	if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_set_palette)
4325 		vc->vc_sw->con_set_palette(vc, color_table);
4326 }
4327 
4328 /*
4329  * Load palette into the DAC registers. arg points to a colour
4330  * map, 3 bytes per colour, 16 colours, range from 0 to 255.
4331  */
4332 
4333 int con_set_cmap(unsigned char __user *arg)
4334 {
4335 	int i, j, k;
4336 	unsigned char colormap[3*16];
4337 
4338 	if (copy_from_user(colormap, arg, sizeof(colormap)))
4339 		return -EFAULT;
4340 
4341 	console_lock();
4342 	for (i = k = 0; i < 16; i++) {
4343 		default_red[i] = colormap[k++];
4344 		default_grn[i] = colormap[k++];
4345 		default_blu[i] = colormap[k++];
4346 	}
4347 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
4348 		if (!vc_cons_allocated(i))
4349 			continue;
4350 		for (j = k = 0; j < 16; j++) {
4351 			vc_cons[i].d->vc_palette[k++] = default_red[j];
4352 			vc_cons[i].d->vc_palette[k++] = default_grn[j];
4353 			vc_cons[i].d->vc_palette[k++] = default_blu[j];
4354 		}
4355 		set_palette(vc_cons[i].d);
4356 	}
4357 	console_unlock();
4358 
4359 	return 0;
4360 }
4361 
4362 int con_get_cmap(unsigned char __user *arg)
4363 {
4364 	int i, k;
4365 	unsigned char colormap[3*16];
4366 
4367 	console_lock();
4368 	for (i = k = 0; i < 16; i++) {
4369 		colormap[k++] = default_red[i];
4370 		colormap[k++] = default_grn[i];
4371 		colormap[k++] = default_blu[i];
4372 	}
4373 	console_unlock();
4374 
4375 	if (copy_to_user(arg, colormap, sizeof(colormap)))
4376 		return -EFAULT;
4377 
4378 	return 0;
4379 }
4380 
4381 void reset_palette(struct vc_data *vc)
4382 {
4383 	int j, k;
4384 	for (j=k=0; j<16; j++) {
4385 		vc->vc_palette[k++] = default_red[j];
4386 		vc->vc_palette[k++] = default_grn[j];
4387 		vc->vc_palette[k++] = default_blu[j];
4388 	}
4389 	set_palette(vc);
4390 }
4391 
4392 /*
4393  *  Font switching
4394  *
4395  *  Currently we only support fonts up to 32 pixels wide, at a maximum height
4396  *  of 32 pixels. Userspace fontdata is stored with 32 bytes (shorts/ints,
4397  *  depending on width) reserved for each character which is kinda wasty, but
4398  *  this is done in order to maintain compatibility with the EGA/VGA fonts. It
4399  *  is up to the actual low-level console-driver convert data into its favorite
4400  *  format (maybe we should add a `fontoffset' field to the `display'
4401  *  structure so we won't have to convert the fontdata all the time.
4402  *  /Jes
4403  */
4404 
4405 #define max_font_size 65536
4406 
4407 static int con_font_get(struct vc_data *vc, struct console_font_op *op)
4408 {
4409 	struct console_font font;
4410 	int rc = -EINVAL;
4411 	int c;
4412 
4413 	if (op->data) {
4414 		font.data = kmalloc(max_font_size, GFP_KERNEL);
4415 		if (!font.data)
4416 			return -ENOMEM;
4417 	} else
4418 		font.data = NULL;
4419 
4420 	console_lock();
4421 	if (vc->vc_mode != KD_TEXT)
4422 		rc = -EINVAL;
4423 	else if (vc->vc_sw->con_font_get)
4424 		rc = vc->vc_sw->con_font_get(vc, &font);
4425 	else
4426 		rc = -ENOSYS;
4427 	console_unlock();
4428 
4429 	if (rc)
4430 		goto out;
4431 
4432 	c = (font.width+7)/8 * 32 * font.charcount;
4433 
4434 	if (op->data && font.charcount > op->charcount)
4435 		rc = -ENOSPC;
4436 	if (!(op->flags & KD_FONT_FLAG_OLD)) {
4437 		if (font.width > op->width || font.height > op->height)
4438 			rc = -ENOSPC;
4439 	} else {
4440 		if (font.width != 8)
4441 			rc = -EIO;
4442 		else if ((op->height && font.height > op->height) ||
4443 			 font.height > 32)
4444 			rc = -ENOSPC;
4445 	}
4446 	if (rc)
4447 		goto out;
4448 
4449 	op->height = font.height;
4450 	op->width = font.width;
4451 	op->charcount = font.charcount;
4452 
4453 	if (op->data && copy_to_user(op->data, font.data, c))
4454 		rc = -EFAULT;
4455 
4456 out:
4457 	kfree(font.data);
4458 	return rc;
4459 }
4460 
4461 static int con_font_set(struct vc_data *vc, struct console_font_op *op)
4462 {
4463 	struct console_font font;
4464 	int rc = -EINVAL;
4465 	int size;
4466 
4467 	if (vc->vc_mode != KD_TEXT)
4468 		return -EINVAL;
4469 	if (!op->data)
4470 		return -EINVAL;
4471 	if (op->charcount > 512)
4472 		return -EINVAL;
4473 	if (op->width <= 0 || op->width > 32 || op->height > 32)
4474 		return -EINVAL;
4475 	size = (op->width+7)/8 * 32 * op->charcount;
4476 	if (size > max_font_size)
4477 		return -ENOSPC;
4478 
4479 	font.data = memdup_user(op->data, size);
4480 	if (IS_ERR(font.data))
4481 		return PTR_ERR(font.data);
4482 
4483 	if (!op->height) {		/* Need to guess font height [compat] */
4484 		int h, i;
4485 		u8 *charmap = font.data;
4486 
4487 		/*
4488 		 * If from KDFONTOP ioctl, don't allow things which can be done
4489 		 * in userland,so that we can get rid of this soon
4490 		 */
4491 		if (!(op->flags & KD_FONT_FLAG_OLD)) {
4492 			kfree(font.data);
4493 			return -EINVAL;
4494 		}
4495 
4496 		for (h = 32; h > 0; h--)
4497 			for (i = 0; i < op->charcount; i++)
4498 				if (charmap[32*i+h-1])
4499 					goto nonzero;
4500 
4501 		kfree(font.data);
4502 		return -EINVAL;
4503 
4504 	nonzero:
4505 		op->height = h;
4506 	}
4507 
4508 	font.charcount = op->charcount;
4509 	font.width = op->width;
4510 	font.height = op->height;
4511 
4512 	console_lock();
4513 	if (vc->vc_mode != KD_TEXT)
4514 		rc = -EINVAL;
4515 	else if (vc->vc_sw->con_font_set)
4516 		rc = vc->vc_sw->con_font_set(vc, &font, op->flags);
4517 	else
4518 		rc = -ENOSYS;
4519 	console_unlock();
4520 	kfree(font.data);
4521 	return rc;
4522 }
4523 
4524 static int con_font_default(struct vc_data *vc, struct console_font_op *op)
4525 {
4526 	struct console_font font = {.width = op->width, .height = op->height};
4527 	char name[MAX_FONT_NAME];
4528 	char *s = name;
4529 	int rc;
4530 
4531 
4532 	if (!op->data)
4533 		s = NULL;
4534 	else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0)
4535 		return -EFAULT;
4536 	else
4537 		name[MAX_FONT_NAME - 1] = 0;
4538 
4539 	console_lock();
4540 	if (vc->vc_mode != KD_TEXT) {
4541 		console_unlock();
4542 		return -EINVAL;
4543 	}
4544 	if (vc->vc_sw->con_font_default)
4545 		rc = vc->vc_sw->con_font_default(vc, &font, s);
4546 	else
4547 		rc = -ENOSYS;
4548 	console_unlock();
4549 	if (!rc) {
4550 		op->width = font.width;
4551 		op->height = font.height;
4552 	}
4553 	return rc;
4554 }
4555 
4556 static int con_font_copy(struct vc_data *vc, struct console_font_op *op)
4557 {
4558 	int con = op->height;
4559 	int rc;
4560 
4561 
4562 	console_lock();
4563 	if (vc->vc_mode != KD_TEXT)
4564 		rc = -EINVAL;
4565 	else if (!vc->vc_sw->con_font_copy)
4566 		rc = -ENOSYS;
4567 	else if (con < 0 || !vc_cons_allocated(con))
4568 		rc = -ENOTTY;
4569 	else if (con == vc->vc_num)	/* nothing to do */
4570 		rc = 0;
4571 	else
4572 		rc = vc->vc_sw->con_font_copy(vc, con);
4573 	console_unlock();
4574 	return rc;
4575 }
4576 
4577 int con_font_op(struct vc_data *vc, struct console_font_op *op)
4578 {
4579 	switch (op->op) {
4580 	case KD_FONT_OP_SET:
4581 		return con_font_set(vc, op);
4582 	case KD_FONT_OP_GET:
4583 		return con_font_get(vc, op);
4584 	case KD_FONT_OP_SET_DEFAULT:
4585 		return con_font_default(vc, op);
4586 	case KD_FONT_OP_COPY:
4587 		return con_font_copy(vc, op);
4588 	}
4589 	return -ENOSYS;
4590 }
4591 
4592 /*
4593  *	Interface exported to selection and vcs.
4594  */
4595 
4596 /* used by selection */
4597 u16 screen_glyph(struct vc_data *vc, int offset)
4598 {
4599 	u16 w = scr_readw(screenpos(vc, offset, 1));
4600 	u16 c = w & 0xff;
4601 
4602 	if (w & vc->vc_hi_font_mask)
4603 		c |= 0x100;
4604 	return c;
4605 }
4606 EXPORT_SYMBOL_GPL(screen_glyph);
4607 
4608 u32 screen_glyph_unicode(struct vc_data *vc, int n)
4609 {
4610 	struct uni_screen *uniscr = get_vc_uniscr(vc);
4611 
4612 	if (uniscr)
4613 		return uniscr->lines[n / vc->vc_cols][n % vc->vc_cols];
4614 	return inverse_translate(vc, screen_glyph(vc, n * 2), 1);
4615 }
4616 EXPORT_SYMBOL_GPL(screen_glyph_unicode);
4617 
4618 /* used by vcs - note the word offset */
4619 unsigned short *screen_pos(struct vc_data *vc, int w_offset, int viewed)
4620 {
4621 	return screenpos(vc, 2 * w_offset, viewed);
4622 }
4623 EXPORT_SYMBOL_GPL(screen_pos);
4624 
4625 void getconsxy(struct vc_data *vc, unsigned char *p)
4626 {
4627 	/* clamp values if they don't fit */
4628 	p[0] = min(vc->vc_x, 0xFFu);
4629 	p[1] = min(vc->vc_y, 0xFFu);
4630 }
4631 
4632 void putconsxy(struct vc_data *vc, unsigned char *p)
4633 {
4634 	hide_cursor(vc);
4635 	gotoxy(vc, p[0], p[1]);
4636 	set_cursor(vc);
4637 }
4638 
4639 u16 vcs_scr_readw(struct vc_data *vc, const u16 *org)
4640 {
4641 	if ((unsigned long)org == vc->vc_pos && softcursor_original != -1)
4642 		return softcursor_original;
4643 	return scr_readw(org);
4644 }
4645 
4646 void vcs_scr_writew(struct vc_data *vc, u16 val, u16 *org)
4647 {
4648 	scr_writew(val, org);
4649 	if ((unsigned long)org == vc->vc_pos) {
4650 		softcursor_original = -1;
4651 		add_softcursor(vc);
4652 	}
4653 }
4654 
4655 void vcs_scr_updated(struct vc_data *vc)
4656 {
4657 	notify_update(vc);
4658 }
4659 
4660 void vc_scrolldelta_helper(struct vc_data *c, int lines,
4661 		unsigned int rolled_over, void *base, unsigned int size)
4662 {
4663 	unsigned long ubase = (unsigned long)base;
4664 	ptrdiff_t scr_end = (void *)c->vc_scr_end - base;
4665 	ptrdiff_t vorigin = (void *)c->vc_visible_origin - base;
4666 	ptrdiff_t origin = (void *)c->vc_origin - base;
4667 	int margin = c->vc_size_row * 4;
4668 	int from, wrap, from_off, avail;
4669 
4670 	/* Turn scrollback off */
4671 	if (!lines) {
4672 		c->vc_visible_origin = c->vc_origin;
4673 		return;
4674 	}
4675 
4676 	/* Do we have already enough to allow jumping from 0 to the end? */
4677 	if (rolled_over > scr_end + margin) {
4678 		from = scr_end;
4679 		wrap = rolled_over + c->vc_size_row;
4680 	} else {
4681 		from = 0;
4682 		wrap = size;
4683 	}
4684 
4685 	from_off = (vorigin - from + wrap) % wrap + lines * c->vc_size_row;
4686 	avail = (origin - from + wrap) % wrap;
4687 
4688 	/* Only a little piece would be left? Show all incl. the piece! */
4689 	if (avail < 2 * margin)
4690 		margin = 0;
4691 	if (from_off < margin)
4692 		from_off = 0;
4693 	if (from_off > avail - margin)
4694 		from_off = avail;
4695 
4696 	c->vc_visible_origin = ubase + (from + from_off) % wrap;
4697 }
4698 EXPORT_SYMBOL_GPL(vc_scrolldelta_helper);
4699 
4700 /*
4701  *	Visible symbols for modules
4702  */
4703 
4704 EXPORT_SYMBOL(color_table);
4705 EXPORT_SYMBOL(default_red);
4706 EXPORT_SYMBOL(default_grn);
4707 EXPORT_SYMBOL(default_blu);
4708 EXPORT_SYMBOL(update_region);
4709 EXPORT_SYMBOL(redraw_screen);
4710 EXPORT_SYMBOL(vc_resize);
4711 EXPORT_SYMBOL(fg_console);
4712 EXPORT_SYMBOL(console_blank_hook);
4713 EXPORT_SYMBOL(console_blanked);
4714 EXPORT_SYMBOL(vc_cons);
4715 EXPORT_SYMBOL(global_cursor_default);
4716 #ifndef VT_SINGLE_DRIVER
4717 EXPORT_SYMBOL(give_up_console);
4718 #endif
4719