xref: /linux/drivers/tty/vt/vt.c (revision 58f504efcda54a9079a38203acc088c3354aaa60)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Copyright (C) 1991, 1992  Linus Torvalds
4  */
5 
6 /*
7  * Hopefully this will be a rather complete VT102 implementation.
8  *
9  * Beeping thanks to John T Kohl.
10  *
11  * Virtual Consoles, Screen Blanking, Screen Dumping, Color, Graphics
12  *   Chars, and VT100 enhancements by Peter MacDonald.
13  *
14  * Copy and paste function by Andrew Haylett,
15  *   some enhancements by Alessandro Rubini.
16  *
17  * Code to check for different video-cards mostly by Galen Hunt,
18  * <g-hunt@ee.utah.edu>
19  *
20  * Rudimentary ISO 10646/Unicode/UTF-8 character set support by
21  * Markus Kuhn, <mskuhn@immd4.informatik.uni-erlangen.de>.
22  *
23  * Dynamic allocation of consoles, aeb@cwi.nl, May 1994
24  * Resizing of consoles, aeb, 940926
25  *
26  * Code for xterm like mouse click reporting by Peter Orbaek 20-Jul-94
27  * <poe@daimi.aau.dk>
28  *
29  * User-defined bell sound, new setterm control sequences and printk
30  * redirection by Martin Mares <mj@k332.feld.cvut.cz> 19-Nov-95
31  *
32  * APM screenblank bug fixed Takashi Manabe <manabe@roy.dsl.tutics.tut.jp>
33  *
34  * Merge with the abstract console driver by Geert Uytterhoeven
35  * <geert@linux-m68k.org>, Jan 1997.
36  *
37  *   Original m68k console driver modifications by
38  *
39  *     - Arno Griffioen <arno@usn.nl>
40  *     - David Carter <carter@cs.bris.ac.uk>
41  *
42  *   The abstract console driver provides a generic interface for a text
43  *   console. It supports VGA text mode, frame buffer based graphical consoles
44  *   and special graphics processors that are only accessible through some
45  *   registers (e.g. a TMS340x0 GSP).
46  *
47  *   The interface to the hardware is specified using a special structure
48  *   (struct consw) which contains function pointers to console operations
49  *   (see <linux/console.h> for more information).
50  *
51  * Support for changeable cursor shape
52  * by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz>, August 1997
53  *
54  * Ported to i386 and con_scrolldelta fixed
55  * by Emmanuel Marty <core@ggi-project.org>, April 1998
56  *
57  * Resurrected character buffers in videoram plus lots of other trickery
58  * by Martin Mares <mj@atrey.karlin.mff.cuni.cz>, July 1998
59  *
60  * Removed old-style timers, introduced console_timer, made timer
61  * deletion SMP-safe.  17Jun00, Andrew Morton
62  *
63  * Removed console_lock, enabled interrupts across all console operations
64  * 13 March 2001, Andrew Morton
65  *
66  * Fixed UTF-8 mode so alternate charset modes always work according
67  * to control sequences interpreted in do_con_trol function
68  * preserving backward VT100 semigraphics compatibility,
69  * malformed UTF sequences represented as sequences of replacement glyphs,
70  * original codes or '?' as a last resort if replacement glyph is undefined
71  * by Adam Tla/lka <atlka@pg.gda.pl>, Aug 2006
72  */
73 
74 #include <linux/module.h>
75 #include <linux/types.h>
76 #include <linux/sched/signal.h>
77 #include <linux/tty.h>
78 #include <linux/tty_flip.h>
79 #include <linux/kernel.h>
80 #include <linux/string.h>
81 #include <linux/errno.h>
82 #include <linux/kd.h>
83 #include <linux/slab.h>
84 #include <linux/vmalloc.h>
85 #include <linux/major.h>
86 #include <linux/mm.h>
87 #include <linux/console.h>
88 #include <linux/init.h>
89 #include <linux/mutex.h>
90 #include <linux/vt_kern.h>
91 #include <linux/selection.h>
92 #include <linux/tiocl.h>
93 #include <linux/kbd_kern.h>
94 #include <linux/consolemap.h>
95 #include <linux/timer.h>
96 #include <linux/interrupt.h>
97 #include <linux/workqueue.h>
98 #include <linux/pm.h>
99 #include <linux/font.h>
100 #include <linux/bitops.h>
101 #include <linux/notifier.h>
102 #include <linux/device.h>
103 #include <linux/io.h>
104 #include <linux/uaccess.h>
105 #include <linux/kdb.h>
106 #include <linux/ctype.h>
107 #include <linux/bsearch.h>
108 #include <linux/gcd.h>
109 
110 #define MAX_NR_CON_DRIVER 16
111 
112 #define CON_DRIVER_FLAG_MODULE 1
113 #define CON_DRIVER_FLAG_INIT   2
114 #define CON_DRIVER_FLAG_ATTR   4
115 #define CON_DRIVER_FLAG_ZOMBIE 8
116 
117 struct con_driver {
118 	const struct consw *con;
119 	const char *desc;
120 	struct device *dev;
121 	int node;
122 	int first;
123 	int last;
124 	int flag;
125 };
126 
127 static struct con_driver registered_con_driver[MAX_NR_CON_DRIVER];
128 const struct consw *conswitchp;
129 
130 /*
131  * Here is the default bell parameters: 750HZ, 1/8th of a second
132  */
133 #define DEFAULT_BELL_PITCH	750
134 #define DEFAULT_BELL_DURATION	(HZ/8)
135 #define DEFAULT_CURSOR_BLINK_MS	200
136 
137 struct vc vc_cons [MAX_NR_CONSOLES];
138 EXPORT_SYMBOL(vc_cons);
139 
140 static const struct consw *con_driver_map[MAX_NR_CONSOLES];
141 
142 static int con_open(struct tty_struct *, struct file *);
143 static void vc_init(struct vc_data *vc, int do_clear);
144 static void gotoxy(struct vc_data *vc, int new_x, int new_y);
145 static void save_cur(struct vc_data *vc);
146 static void reset_terminal(struct vc_data *vc, int do_clear);
147 static void con_flush_chars(struct tty_struct *tty);
148 static int set_vesa_blanking(u8 __user *mode);
149 static void set_cursor(struct vc_data *vc);
150 static void hide_cursor(struct vc_data *vc);
151 static void console_callback(struct work_struct *ignored);
152 static void con_driver_unregister_callback(struct work_struct *ignored);
153 static void blank_screen_t(struct timer_list *unused);
154 static void set_palette(struct vc_data *vc);
155 static void unblank_screen(void);
156 
157 #define vt_get_kmsg_redirect() vt_kmsg_redirect(-1)
158 
159 int default_utf8 = true;
160 module_param(default_utf8, int, S_IRUGO | S_IWUSR);
161 int global_cursor_default = -1;
162 module_param(global_cursor_default, int, S_IRUGO | S_IWUSR);
163 EXPORT_SYMBOL(global_cursor_default);
164 
165 static int cur_default = CUR_UNDERLINE;
166 module_param(cur_default, int, S_IRUGO | S_IWUSR);
167 
168 /*
169  * ignore_poke: don't unblank the screen when things are typed.  This is
170  * mainly for the privacy of braille terminal users.
171  */
172 static int ignore_poke;
173 
174 int do_poke_blanked_console;
175 int console_blanked;
176 EXPORT_SYMBOL(console_blanked);
177 
178 static enum vesa_blank_mode vesa_blank_mode;
179 static int vesa_off_interval;
180 static int blankinterval;
181 core_param(consoleblank, blankinterval, int, 0444);
182 
183 static DECLARE_WORK(console_work, console_callback);
184 static DECLARE_WORK(con_driver_unregister_work, con_driver_unregister_callback);
185 
186 /*
187  * fg_console is the current virtual console,
188  * last_console is the last used one,
189  * want_console is the console we want to switch to,
190  * saved_* variants are for save/restore around kernel debugger enter/leave
191  */
192 int fg_console;
193 EXPORT_SYMBOL(fg_console);
194 int last_console;
195 int want_console = -1;
196 
197 static int saved_fg_console;
198 static int saved_last_console;
199 static int saved_want_console;
200 static int saved_vc_mode;
201 static int saved_console_blanked;
202 
203 /*
204  * For each existing display, we have a pointer to console currently visible
205  * on that display, allowing consoles other than fg_console to be refreshed
206  * appropriately. Unless the low-level driver supplies its own display_fg
207  * variable, we use this one for the "master display".
208  */
209 static struct vc_data *master_display_fg;
210 
211 /*
212  * Unfortunately, we need to delay tty echo when we're currently writing to the
213  * console since the code is (and always was) not re-entrant, so we schedule
214  * all flip requests to process context with schedule-task() and run it from
215  * console_callback().
216  */
217 
218 /*
219  * For the same reason, we defer scrollback to the console callback.
220  */
221 static int scrollback_delta;
222 
223 /*
224  * Hook so that the power management routines can (un)blank
225  * the console on our behalf.
226  */
227 int (*console_blank_hook)(int);
228 EXPORT_SYMBOL(console_blank_hook);
229 
230 static DEFINE_TIMER(console_timer, blank_screen_t);
231 static int blank_state;
232 static int blank_timer_expired;
233 enum {
234 	blank_off = 0,
235 	blank_normal_wait,
236 	blank_vesa_wait,
237 };
238 
239 /*
240  * /sys/class/tty/tty0/
241  *
242  * the attribute 'active' contains the name of the current vc
243  * console and it supports poll() to detect vc switches
244  */
245 static struct device *tty0dev;
246 
247 /*
248  * Notifier list for console events.
249  */
250 static ATOMIC_NOTIFIER_HEAD(vt_notifier_list);
251 
252 int register_vt_notifier(struct notifier_block *nb)
253 {
254 	return atomic_notifier_chain_register(&vt_notifier_list, nb);
255 }
256 EXPORT_SYMBOL_GPL(register_vt_notifier);
257 
258 int unregister_vt_notifier(struct notifier_block *nb)
259 {
260 	return atomic_notifier_chain_unregister(&vt_notifier_list, nb);
261 }
262 EXPORT_SYMBOL_GPL(unregister_vt_notifier);
263 
264 static void notify_write(struct vc_data *vc, unsigned int unicode)
265 {
266 	struct vt_notifier_param param = { .vc = vc, .c = unicode };
267 	atomic_notifier_call_chain(&vt_notifier_list, VT_WRITE, &param);
268 }
269 
270 static void notify_update(struct vc_data *vc)
271 {
272 	struct vt_notifier_param param = { .vc = vc };
273 	atomic_notifier_call_chain(&vt_notifier_list, VT_UPDATE, &param);
274 }
275 /*
276  *	Low-Level Functions
277  */
278 
279 static inline bool con_is_fg(const struct vc_data *vc)
280 {
281 	return vc->vc_num == fg_console;
282 }
283 
284 static inline bool con_should_update(const struct vc_data *vc)
285 {
286 	return con_is_visible(vc) && !console_blanked;
287 }
288 
289 static inline u16 *screenpos(const struct vc_data *vc, unsigned int offset,
290 			     bool viewed)
291 {
292 	unsigned long origin = viewed ? vc->vc_visible_origin : vc->vc_origin;
293 
294 	return (u16 *)(origin + offset);
295 }
296 
297 static void con_putc(struct vc_data *vc, u16 ca, unsigned int y, unsigned int x)
298 {
299 	if (vc->vc_sw->con_putc)
300 		vc->vc_sw->con_putc(vc, ca, y, x);
301 	else
302 		vc->vc_sw->con_putcs(vc, &ca, 1, y, x);
303 }
304 
305 /* Called  from the keyboard irq path.. */
306 static inline void scrolldelta(int lines)
307 {
308 	/* FIXME */
309 	/* scrolldelta needs some kind of consistency lock, but the BKL was
310 	   and still is not protecting versus the scheduled back end */
311 	scrollback_delta += lines;
312 	schedule_console_callback();
313 }
314 
315 void schedule_console_callback(void)
316 {
317 	schedule_work(&console_work);
318 }
319 
320 /*
321  * Code to manage unicode-based screen buffers
322  */
323 
324 /*
325  * Our screen buffer is preceded by an array of line pointers so that
326  * scrolling only implies some pointer shuffling.
327  */
328 
329 static u32 **vc_uniscr_alloc(unsigned int cols, unsigned int rows)
330 {
331 	u32 **uni_lines;
332 	void *p;
333 	unsigned int memsize, i, col_size = cols * sizeof(**uni_lines);
334 
335 	/* allocate everything in one go */
336 	memsize = col_size * rows;
337 	memsize += rows * sizeof(*uni_lines);
338 	uni_lines = vzalloc(memsize);
339 	if (!uni_lines)
340 		return NULL;
341 
342 	/* initial line pointers */
343 	p = uni_lines + rows;
344 	for (i = 0; i < rows; i++) {
345 		uni_lines[i] = p;
346 		p += col_size;
347 	}
348 
349 	return uni_lines;
350 }
351 
352 static void vc_uniscr_free(u32 **uni_lines)
353 {
354 	vfree(uni_lines);
355 }
356 
357 static void vc_uniscr_set(struct vc_data *vc, u32 **new_uni_lines)
358 {
359 	vc_uniscr_free(vc->vc_uni_lines);
360 	vc->vc_uni_lines = new_uni_lines;
361 }
362 
363 static void vc_uniscr_putc(struct vc_data *vc, u32 uc)
364 {
365 	if (vc->vc_uni_lines)
366 		vc->vc_uni_lines[vc->state.y][vc->state.x] = uc;
367 }
368 
369 static void vc_uniscr_insert(struct vc_data *vc, unsigned int nr)
370 {
371 	if (vc->vc_uni_lines) {
372 		u32 *ln = vc->vc_uni_lines[vc->state.y];
373 		unsigned int x = vc->state.x, cols = vc->vc_cols;
374 
375 		memmove(&ln[x + nr], &ln[x], (cols - x - nr) * sizeof(*ln));
376 		memset32(&ln[x], ' ', nr);
377 	}
378 }
379 
380 static void vc_uniscr_delete(struct vc_data *vc, unsigned int nr)
381 {
382 	if (vc->vc_uni_lines) {
383 		u32 *ln = vc->vc_uni_lines[vc->state.y];
384 		unsigned int x = vc->state.x, cols = vc->vc_cols;
385 
386 		memmove(&ln[x], &ln[x + nr], (cols - x - nr) * sizeof(*ln));
387 		memset32(&ln[cols - nr], ' ', nr);
388 	}
389 }
390 
391 static void vc_uniscr_clear_line(struct vc_data *vc, unsigned int x,
392 				 unsigned int nr)
393 {
394 	if (vc->vc_uni_lines)
395 		memset32(&vc->vc_uni_lines[vc->state.y][x], ' ', nr);
396 }
397 
398 static void vc_uniscr_clear_lines(struct vc_data *vc, unsigned int y,
399 				  unsigned int nr)
400 {
401 	if (vc->vc_uni_lines)
402 		while (nr--)
403 			memset32(vc->vc_uni_lines[y++], ' ', vc->vc_cols);
404 }
405 
406 /* juggling array rotation algorithm (complexity O(N), size complexity O(1)) */
407 static void juggle_array(u32 **array, unsigned int size, unsigned int nr)
408 {
409 	unsigned int gcd_idx;
410 
411 	for (gcd_idx = 0; gcd_idx < gcd(nr, size); gcd_idx++) {
412 		u32 *gcd_idx_val = array[gcd_idx];
413 		unsigned int dst_idx = gcd_idx;
414 
415 		while (1) {
416 			unsigned int src_idx = (dst_idx + nr) % size;
417 			if (src_idx == gcd_idx)
418 				break;
419 
420 			array[dst_idx] = array[src_idx];
421 			dst_idx = src_idx;
422 		}
423 
424 		array[dst_idx] = gcd_idx_val;
425 	}
426 }
427 
428 static void vc_uniscr_scroll(struct vc_data *vc, unsigned int top,
429 			     unsigned int bottom, enum con_scroll dir,
430 			     unsigned int nr)
431 {
432 	u32 **uni_lines = vc->vc_uni_lines;
433 	unsigned int size = bottom - top;
434 
435 	if (!uni_lines)
436 		return;
437 
438 	if (dir == SM_DOWN) {
439 		juggle_array(&uni_lines[top], size, size - nr);
440 		vc_uniscr_clear_lines(vc, top, nr);
441 	} else {
442 		juggle_array(&uni_lines[top], size, nr);
443 		vc_uniscr_clear_lines(vc, bottom - nr, nr);
444 	}
445 }
446 
447 static void vc_uniscr_copy_area(u32 **dst_lines,
448 				unsigned int dst_cols,
449 				unsigned int dst_rows,
450 				u32 **src_lines,
451 				unsigned int src_cols,
452 				unsigned int src_top_row,
453 				unsigned int src_bot_row)
454 {
455 	unsigned int dst_row = 0;
456 
457 	if (!dst_lines)
458 		return;
459 
460 	while (src_top_row < src_bot_row) {
461 		u32 *src_line = src_lines[src_top_row];
462 		u32 *dst_line = dst_lines[dst_row];
463 
464 		memcpy(dst_line, src_line, src_cols * sizeof(*src_line));
465 		if (dst_cols - src_cols)
466 			memset32(dst_line + src_cols, ' ', dst_cols - src_cols);
467 		src_top_row++;
468 		dst_row++;
469 	}
470 	while (dst_row < dst_rows) {
471 		u32 *dst_line = dst_lines[dst_row];
472 
473 		memset32(dst_line, ' ', dst_cols);
474 		dst_row++;
475 	}
476 }
477 
478 /*
479  * Called from vcs_read() to make sure unicode screen retrieval is possible.
480  * This will initialize the unicode screen buffer if not already done.
481  * This returns 0 if OK, or a negative error code otherwise.
482  * In particular, -ENODATA is returned if the console is not in UTF-8 mode.
483  */
484 int vc_uniscr_check(struct vc_data *vc)
485 {
486 	u32 **uni_lines;
487 	unsigned short *p;
488 	int x, y, mask;
489 
490 	WARN_CONSOLE_UNLOCKED();
491 
492 	if (!vc->vc_utf)
493 		return -ENODATA;
494 
495 	if (vc->vc_uni_lines)
496 		return 0;
497 
498 	uni_lines = vc_uniscr_alloc(vc->vc_cols, vc->vc_rows);
499 	if (!uni_lines)
500 		return -ENOMEM;
501 
502 	/*
503 	 * Let's populate it initially with (imperfect) reverse translation.
504 	 * This is the next best thing we can do short of having it enabled
505 	 * from the start even when no users rely on this functionality. True
506 	 * unicode content will be available after a complete screen refresh.
507 	 */
508 	p = (unsigned short *)vc->vc_origin;
509 	mask = vc->vc_hi_font_mask | 0xff;
510 	for (y = 0; y < vc->vc_rows; y++) {
511 		u32 *line = uni_lines[y];
512 		for (x = 0; x < vc->vc_cols; x++) {
513 			u16 glyph = scr_readw(p++) & mask;
514 			line[x] = inverse_translate(vc, glyph, true);
515 		}
516 	}
517 
518 	vc->vc_uni_lines = uni_lines;
519 
520 	return 0;
521 }
522 
523 /*
524  * Called from vcs_read() to get the unicode data from the screen.
525  * This must be preceded by a successful call to vc_uniscr_check() once
526  * the console lock has been taken.
527  */
528 void vc_uniscr_copy_line(const struct vc_data *vc, void *dest, bool viewed,
529 			 unsigned int row, unsigned int col, unsigned int nr)
530 {
531 	u32 **uni_lines = vc->vc_uni_lines;
532 	int offset = row * vc->vc_size_row + col * 2;
533 	unsigned long pos;
534 
535 	if (WARN_ON_ONCE(!uni_lines))
536 		return;
537 
538 	pos = (unsigned long)screenpos(vc, offset, viewed);
539 	if (pos >= vc->vc_origin && pos < vc->vc_scr_end) {
540 		/*
541 		 * Desired position falls in the main screen buffer.
542 		 * However the actual row/col might be different if
543 		 * scrollback is active.
544 		 */
545 		row = (pos - vc->vc_origin) / vc->vc_size_row;
546 		col = ((pos - vc->vc_origin) % vc->vc_size_row) / 2;
547 		memcpy(dest, &uni_lines[row][col], nr * sizeof(u32));
548 	} else {
549 		/*
550 		 * Scrollback is active. For now let's simply backtranslate
551 		 * the screen glyphs until the unicode screen buffer does
552 		 * synchronize with console display drivers for a scrollback
553 		 * buffer of its own.
554 		 */
555 		u16 *p = (u16 *)pos;
556 		int mask = vc->vc_hi_font_mask | 0xff;
557 		u32 *uni_buf = dest;
558 		while (nr--) {
559 			u16 glyph = scr_readw(p++) & mask;
560 			*uni_buf++ = inverse_translate(vc, glyph, true);
561 		}
562 	}
563 }
564 
565 static void con_scroll(struct vc_data *vc, unsigned int top,
566 		       unsigned int bottom, enum con_scroll dir,
567 		       unsigned int nr)
568 {
569 	unsigned int rows = bottom - top;
570 	u16 *clear, *dst, *src;
571 
572 	if (top + nr >= bottom)
573 		nr = rows - 1;
574 	if (bottom > vc->vc_rows || top >= bottom || nr < 1)
575 		return;
576 
577 	vc_uniscr_scroll(vc, top, bottom, dir, nr);
578 	if (con_is_visible(vc) &&
579 			vc->vc_sw->con_scroll(vc, top, bottom, dir, nr))
580 		return;
581 
582 	src = clear = (u16 *)(vc->vc_origin + vc->vc_size_row * top);
583 	dst = (u16 *)(vc->vc_origin + vc->vc_size_row * (top + nr));
584 
585 	if (dir == SM_UP) {
586 		clear = src + (rows - nr) * vc->vc_cols;
587 		swap(src, dst);
588 	}
589 	scr_memmovew(dst, src, (rows - nr) * vc->vc_size_row);
590 	scr_memsetw(clear, vc->vc_video_erase_char, vc->vc_size_row * nr);
591 }
592 
593 static void do_update_region(struct vc_data *vc, unsigned long start, int count)
594 {
595 	unsigned int xx, yy, offset;
596 	u16 *p = (u16 *)start;
597 
598 	offset = (start - vc->vc_origin) / 2;
599 	xx = offset % vc->vc_cols;
600 	yy = offset / vc->vc_cols;
601 
602 	for(;;) {
603 		u16 attrib = scr_readw(p) & 0xff00;
604 		int startx = xx;
605 		u16 *q = p;
606 		while (xx < vc->vc_cols && count) {
607 			if (attrib != (scr_readw(p) & 0xff00)) {
608 				if (p > q)
609 					vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
610 				startx = xx;
611 				q = p;
612 				attrib = scr_readw(p) & 0xff00;
613 			}
614 			p++;
615 			xx++;
616 			count--;
617 		}
618 		if (p > q)
619 			vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
620 		if (!count)
621 			break;
622 		xx = 0;
623 		yy++;
624 	}
625 }
626 
627 void update_region(struct vc_data *vc, unsigned long start, int count)
628 {
629 	WARN_CONSOLE_UNLOCKED();
630 
631 	if (con_should_update(vc)) {
632 		hide_cursor(vc);
633 		do_update_region(vc, start, count);
634 		set_cursor(vc);
635 	}
636 }
637 EXPORT_SYMBOL(update_region);
638 
639 /* Structure of attributes is hardware-dependent */
640 
641 static u8 build_attr(struct vc_data *vc, u8 _color,
642 		enum vc_intensity _intensity, bool _blink, bool _underline,
643 		bool _reverse, bool _italic)
644 {
645 	if (vc->vc_sw->con_build_attr)
646 		return vc->vc_sw->con_build_attr(vc, _color, _intensity,
647 		       _blink, _underline, _reverse, _italic);
648 
649 /*
650  * ++roman: I completely changed the attribute format for monochrome
651  * mode (!can_do_color). The formerly used MDA (monochrome display
652  * adapter) format didn't allow the combination of certain effects.
653  * Now the attribute is just a bit vector:
654  *  Bit 0..1: intensity (0..2)
655  *  Bit 2   : underline
656  *  Bit 3   : reverse
657  *  Bit 7   : blink
658  */
659 	{
660 	u8 a = _color;
661 	if (!vc->vc_can_do_color)
662 		return _intensity |
663 		       (_italic    << 1) |
664 		       (_underline << 2) |
665 		       (_reverse   << 3) |
666 		       (_blink     << 7);
667 	if (_italic)
668 		a = (a & 0xF0) | vc->vc_itcolor;
669 	else if (_underline)
670 		a = (a & 0xf0) | vc->vc_ulcolor;
671 	else if (_intensity == VCI_HALF_BRIGHT)
672 		a = (a & 0xf0) | vc->vc_halfcolor;
673 	if (_reverse)
674 		a = (a & 0x88) | (((a >> 4) | (a << 4)) & 0x77);
675 	if (_blink)
676 		a ^= 0x80;
677 	if (_intensity == VCI_BOLD)
678 		a ^= 0x08;
679 	if (vc->vc_hi_font_mask == 0x100)
680 		a <<= 1;
681 	return a;
682 	}
683 }
684 
685 static void update_attr(struct vc_data *vc)
686 {
687 	vc->vc_attr = build_attr(vc, vc->state.color, vc->state.intensity,
688 	              vc->state.blink, vc->state.underline,
689 	              vc->state.reverse ^ vc->vc_decscnm, vc->state.italic);
690 	vc->vc_video_erase_char = ' ' | (build_attr(vc, vc->state.color,
691 				VCI_NORMAL, vc->state.blink, false,
692 				vc->vc_decscnm, false) << 8);
693 }
694 
695 /* Note: inverting the screen twice should revert to the original state */
696 void invert_screen(struct vc_data *vc, int offset, int count, bool viewed)
697 {
698 	u16 *p;
699 
700 	WARN_CONSOLE_UNLOCKED();
701 
702 	count /= 2;
703 	p = screenpos(vc, offset, viewed);
704 	if (vc->vc_sw->con_invert_region) {
705 		vc->vc_sw->con_invert_region(vc, p, count);
706 	} else {
707 		u16 *q = p;
708 		int cnt = count;
709 		u16 a;
710 
711 		if (!vc->vc_can_do_color) {
712 			while (cnt--) {
713 			    a = scr_readw(q);
714 			    a ^= 0x0800;
715 			    scr_writew(a, q);
716 			    q++;
717 			}
718 		} else if (vc->vc_hi_font_mask == 0x100) {
719 			while (cnt--) {
720 				a = scr_readw(q);
721 				a = (a & 0x11ff) |
722 				   ((a & 0xe000) >> 4) |
723 				   ((a & 0x0e00) << 4);
724 				scr_writew(a, q);
725 				q++;
726 			}
727 		} else {
728 			while (cnt--) {
729 				a = scr_readw(q);
730 				a = (a & 0x88ff) |
731 				   ((a & 0x7000) >> 4) |
732 				   ((a & 0x0700) << 4);
733 				scr_writew(a, q);
734 				q++;
735 			}
736 		}
737 	}
738 
739 	if (con_should_update(vc))
740 		do_update_region(vc, (unsigned long) p, count);
741 	notify_update(vc);
742 }
743 
744 /* used by selection: complement pointer position */
745 void complement_pos(struct vc_data *vc, int offset)
746 {
747 	static int old_offset = -1;
748 	static unsigned short old;
749 	static unsigned short oldx, oldy;
750 
751 	WARN_CONSOLE_UNLOCKED();
752 
753 	if (old_offset != -1 && old_offset >= 0 &&
754 	    old_offset < vc->vc_screenbuf_size) {
755 		scr_writew(old, screenpos(vc, old_offset, true));
756 		if (con_should_update(vc))
757 			con_putc(vc, old, oldy, oldx);
758 		notify_update(vc);
759 	}
760 
761 	old_offset = offset;
762 
763 	if (offset != -1 && offset >= 0 &&
764 	    offset < vc->vc_screenbuf_size) {
765 		unsigned short new;
766 		u16 *p = screenpos(vc, offset, true);
767 		old = scr_readw(p);
768 		new = old ^ vc->vc_complement_mask;
769 		scr_writew(new, p);
770 		if (con_should_update(vc)) {
771 			oldx = (offset >> 1) % vc->vc_cols;
772 			oldy = (offset >> 1) / vc->vc_cols;
773 			con_putc(vc, new, oldy, oldx);
774 		}
775 		notify_update(vc);
776 	}
777 }
778 
779 static void insert_char(struct vc_data *vc, unsigned int nr)
780 {
781 	unsigned short *p = (unsigned short *) vc->vc_pos;
782 
783 	vc_uniscr_insert(vc, nr);
784 	scr_memmovew(p + nr, p, (vc->vc_cols - vc->state.x - nr) * 2);
785 	scr_memsetw(p, vc->vc_video_erase_char, nr * 2);
786 	vc->vc_need_wrap = 0;
787 	if (con_should_update(vc))
788 		do_update_region(vc, (unsigned long) p,
789 			vc->vc_cols - vc->state.x);
790 }
791 
792 static void delete_char(struct vc_data *vc, unsigned int nr)
793 {
794 	unsigned short *p = (unsigned short *) vc->vc_pos;
795 
796 	vc_uniscr_delete(vc, nr);
797 	scr_memmovew(p, p + nr, (vc->vc_cols - vc->state.x - nr) * 2);
798 	scr_memsetw(p + vc->vc_cols - vc->state.x - nr, vc->vc_video_erase_char,
799 			nr * 2);
800 	vc->vc_need_wrap = 0;
801 	if (con_should_update(vc))
802 		do_update_region(vc, (unsigned long) p,
803 			vc->vc_cols - vc->state.x);
804 }
805 
806 static int softcursor_original = -1;
807 
808 static void add_softcursor(struct vc_data *vc)
809 {
810 	int i = scr_readw((u16 *) vc->vc_pos);
811 	u32 type = vc->vc_cursor_type;
812 
813 	if (!(type & CUR_SW))
814 		return;
815 	if (softcursor_original != -1)
816 		return;
817 	softcursor_original = i;
818 	i |= CUR_SET(type);
819 	i ^= CUR_CHANGE(type);
820 	if ((type & CUR_ALWAYS_BG) &&
821 			(softcursor_original & CUR_BG) == (i & CUR_BG))
822 		i ^= CUR_BG;
823 	if ((type & CUR_INVERT_FG_BG) && (i & CUR_FG) == ((i & CUR_BG) >> 4))
824 		i ^= CUR_FG;
825 	scr_writew(i, (u16 *)vc->vc_pos);
826 	if (con_should_update(vc))
827 		con_putc(vc, i, vc->state.y, vc->state.x);
828 }
829 
830 static void hide_softcursor(struct vc_data *vc)
831 {
832 	if (softcursor_original != -1) {
833 		scr_writew(softcursor_original, (u16 *)vc->vc_pos);
834 		if (con_should_update(vc))
835 			con_putc(vc, softcursor_original, vc->state.y,
836 				 vc->state.x);
837 		softcursor_original = -1;
838 	}
839 }
840 
841 static void hide_cursor(struct vc_data *vc)
842 {
843 	if (vc_is_sel(vc))
844 		clear_selection();
845 
846 	vc->vc_sw->con_cursor(vc, false);
847 	hide_softcursor(vc);
848 }
849 
850 static void set_cursor(struct vc_data *vc)
851 {
852 	if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS)
853 		return;
854 	if (vc->vc_deccm) {
855 		if (vc_is_sel(vc))
856 			clear_selection();
857 		add_softcursor(vc);
858 		if (CUR_SIZE(vc->vc_cursor_type) != CUR_NONE)
859 			vc->vc_sw->con_cursor(vc, true);
860 	} else
861 		hide_cursor(vc);
862 }
863 
864 static void set_origin(struct vc_data *vc)
865 {
866 	WARN_CONSOLE_UNLOCKED();
867 
868 	if (!con_is_visible(vc) ||
869 	    !vc->vc_sw->con_set_origin ||
870 	    !vc->vc_sw->con_set_origin(vc))
871 		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
872 	vc->vc_visible_origin = vc->vc_origin;
873 	vc->vc_scr_end = vc->vc_origin + vc->vc_screenbuf_size;
874 	vc->vc_pos = vc->vc_origin + vc->vc_size_row * vc->state.y +
875 		2 * vc->state.x;
876 }
877 
878 static void save_screen(struct vc_data *vc)
879 {
880 	WARN_CONSOLE_UNLOCKED();
881 
882 	if (vc->vc_sw->con_save_screen)
883 		vc->vc_sw->con_save_screen(vc);
884 }
885 
886 static void flush_scrollback(struct vc_data *vc)
887 {
888 	WARN_CONSOLE_UNLOCKED();
889 
890 	set_origin(vc);
891 	if (!con_is_visible(vc))
892 		return;
893 
894 	/*
895 	 * The legacy way for flushing the scrollback buffer is to use a side
896 	 * effect of the con_switch method. We do it only on the foreground
897 	 * console as background consoles have no scrollback buffers in that
898 	 * case and we obviously don't want to switch to them.
899 	 */
900 	hide_cursor(vc);
901 	vc->vc_sw->con_switch(vc);
902 	set_cursor(vc);
903 }
904 
905 /*
906  *	Redrawing of screen
907  */
908 
909 void clear_buffer_attributes(struct vc_data *vc)
910 {
911 	unsigned short *p = (unsigned short *)vc->vc_origin;
912 	int count = vc->vc_screenbuf_size / 2;
913 	int mask = vc->vc_hi_font_mask | 0xff;
914 
915 	for (; count > 0; count--, p++) {
916 		scr_writew((scr_readw(p)&mask) | (vc->vc_video_erase_char & ~mask), p);
917 	}
918 }
919 
920 void redraw_screen(struct vc_data *vc, int is_switch)
921 {
922 	int redraw = 0;
923 
924 	WARN_CONSOLE_UNLOCKED();
925 
926 	if (!vc) {
927 		/* strange ... */
928 		/* printk("redraw_screen: tty %d not allocated ??\n", new_console+1); */
929 		return;
930 	}
931 
932 	if (is_switch) {
933 		struct vc_data *old_vc = vc_cons[fg_console].d;
934 		if (old_vc == vc)
935 			return;
936 		if (!con_is_visible(vc))
937 			redraw = 1;
938 		*vc->vc_display_fg = vc;
939 		fg_console = vc->vc_num;
940 		hide_cursor(old_vc);
941 		if (!con_is_visible(old_vc)) {
942 			save_screen(old_vc);
943 			set_origin(old_vc);
944 		}
945 		if (tty0dev)
946 			sysfs_notify(&tty0dev->kobj, NULL, "active");
947 	} else {
948 		hide_cursor(vc);
949 		redraw = 1;
950 	}
951 
952 	if (redraw) {
953 		bool update;
954 		int old_was_color = vc->vc_can_do_color;
955 
956 		set_origin(vc);
957 		update = vc->vc_sw->con_switch(vc);
958 		set_palette(vc);
959 		/*
960 		 * If console changed from mono<->color, the best we can do
961 		 * is to clear the buffer attributes. As it currently stands,
962 		 * rebuilding new attributes from the old buffer is not doable
963 		 * without overly complex code.
964 		 */
965 		if (old_was_color != vc->vc_can_do_color) {
966 			update_attr(vc);
967 			clear_buffer_attributes(vc);
968 		}
969 
970 		if (update && vc->vc_mode != KD_GRAPHICS)
971 			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
972 	}
973 	set_cursor(vc);
974 	if (is_switch) {
975 		vt_set_leds_compute_shiftstate();
976 		notify_update(vc);
977 	}
978 }
979 EXPORT_SYMBOL(redraw_screen);
980 
981 /*
982  *	Allocation, freeing and resizing of VTs.
983  */
984 
985 int vc_cons_allocated(unsigned int i)
986 {
987 	return (i < MAX_NR_CONSOLES && vc_cons[i].d);
988 }
989 
990 static void visual_init(struct vc_data *vc, int num, bool init)
991 {
992 	/* ++Geert: vc->vc_sw->con_init determines console size */
993 	if (vc->vc_sw)
994 		module_put(vc->vc_sw->owner);
995 	vc->vc_sw = conswitchp;
996 
997 	if (con_driver_map[num])
998 		vc->vc_sw = con_driver_map[num];
999 
1000 	__module_get(vc->vc_sw->owner);
1001 	vc->vc_num = num;
1002 	vc->vc_display_fg = &master_display_fg;
1003 	if (vc->uni_pagedict_loc)
1004 		con_free_unimap(vc);
1005 	vc->uni_pagedict_loc = &vc->uni_pagedict;
1006 	vc->uni_pagedict = NULL;
1007 	vc->vc_hi_font_mask = 0;
1008 	vc->vc_complement_mask = 0;
1009 	vc->vc_can_do_color = 0;
1010 	vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1011 	vc->vc_sw->con_init(vc, init);
1012 	if (!vc->vc_complement_mask)
1013 		vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
1014 	vc->vc_s_complement_mask = vc->vc_complement_mask;
1015 	vc->vc_size_row = vc->vc_cols << 1;
1016 	vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
1017 }
1018 
1019 
1020 static void visual_deinit(struct vc_data *vc)
1021 {
1022 	vc->vc_sw->con_deinit(vc);
1023 	module_put(vc->vc_sw->owner);
1024 }
1025 
1026 static void vc_port_destruct(struct tty_port *port)
1027 {
1028 	struct vc_data *vc = container_of(port, struct vc_data, port);
1029 
1030 	kfree(vc);
1031 }
1032 
1033 static const struct tty_port_operations vc_port_ops = {
1034 	.destruct = vc_port_destruct,
1035 };
1036 
1037 /*
1038  * Change # of rows and columns (0 means unchanged/the size of fg_console)
1039  * [this is to be used together with some user program
1040  * like resize that changes the hardware videomode]
1041  */
1042 #define VC_MAXCOL (32767)
1043 #define VC_MAXROW (32767)
1044 
1045 int vc_allocate(unsigned int currcons)	/* return 0 on success */
1046 {
1047 	struct vt_notifier_param param;
1048 	struct vc_data *vc;
1049 	int err;
1050 
1051 	WARN_CONSOLE_UNLOCKED();
1052 
1053 	if (currcons >= MAX_NR_CONSOLES)
1054 		return -ENXIO;
1055 
1056 	if (vc_cons[currcons].d)
1057 		return 0;
1058 
1059 	/* due to the granularity of kmalloc, we waste some memory here */
1060 	/* the alloc is done in two steps, to optimize the common situation
1061 	   of a 25x80 console (structsize=216, screenbuf_size=4000) */
1062 	/* although the numbers above are not valid since long ago, the
1063 	   point is still up-to-date and the comment still has its value
1064 	   even if only as a historical artifact.  --mj, July 1998 */
1065 	param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL);
1066 	if (!vc)
1067 		return -ENOMEM;
1068 
1069 	vc_cons[currcons].d = vc;
1070 	tty_port_init(&vc->port);
1071 	vc->port.ops = &vc_port_ops;
1072 	INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
1073 
1074 	visual_init(vc, currcons, true);
1075 
1076 	if (!*vc->uni_pagedict_loc)
1077 		con_set_default_unimap(vc);
1078 
1079 	err = -EINVAL;
1080 	if (vc->vc_cols > VC_MAXCOL || vc->vc_rows > VC_MAXROW ||
1081 	    vc->vc_screenbuf_size > KMALLOC_MAX_SIZE || !vc->vc_screenbuf_size)
1082 		goto err_free;
1083 	err = -ENOMEM;
1084 	vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
1085 	if (!vc->vc_screenbuf)
1086 		goto err_free;
1087 
1088 	/* If no drivers have overridden us and the user didn't pass a
1089 	   boot option, default to displaying the cursor */
1090 	if (global_cursor_default == -1)
1091 		global_cursor_default = 1;
1092 
1093 	vc_init(vc, 1);
1094 	vcs_make_sysfs(currcons);
1095 	atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, &param);
1096 
1097 	return 0;
1098 err_free:
1099 	visual_deinit(vc);
1100 	kfree(vc);
1101 	vc_cons[currcons].d = NULL;
1102 	return err;
1103 }
1104 
1105 static inline int resize_screen(struct vc_data *vc, int width, int height,
1106 				bool from_user)
1107 {
1108 	/* Resizes the resolution of the display adapater */
1109 	int err = 0;
1110 
1111 	if (vc->vc_sw->con_resize)
1112 		err = vc->vc_sw->con_resize(vc, width, height, from_user);
1113 
1114 	return err;
1115 }
1116 
1117 /**
1118  * vc_do_resize - resizing method for the tty
1119  * @tty: tty being resized
1120  * @vc: virtual console private data
1121  * @cols: columns
1122  * @lines: lines
1123  * @from_user: invoked by a user?
1124  *
1125  * Resize a virtual console, clipping according to the actual constraints. If
1126  * the caller passes a tty structure then update the termios winsize
1127  * information and perform any necessary signal handling.
1128  *
1129  * Locking: Caller must hold the console semaphore. Takes the termios rwsem and
1130  * ctrl.lock of the tty IFF a tty is passed.
1131  */
1132 static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
1133 			unsigned int cols, unsigned int lines, bool from_user)
1134 {
1135 	unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
1136 	unsigned long end;
1137 	unsigned int old_rows, old_row_size, first_copied_row;
1138 	unsigned int new_cols, new_rows, new_row_size, new_screen_size;
1139 	unsigned short *oldscreen, *newscreen;
1140 	u32 **new_uniscr = NULL;
1141 
1142 	WARN_CONSOLE_UNLOCKED();
1143 
1144 	if (cols > VC_MAXCOL || lines > VC_MAXROW)
1145 		return -EINVAL;
1146 
1147 	new_cols = (cols ? cols : vc->vc_cols);
1148 	new_rows = (lines ? lines : vc->vc_rows);
1149 	new_row_size = new_cols << 1;
1150 	new_screen_size = new_row_size * new_rows;
1151 
1152 	if (new_cols == vc->vc_cols && new_rows == vc->vc_rows) {
1153 		/*
1154 		 * This function is being called here to cover the case
1155 		 * where the userspace calls the FBIOPUT_VSCREENINFO twice,
1156 		 * passing the same fb_var_screeninfo containing the fields
1157 		 * yres/xres equal to a number non-multiple of vc_font.height
1158 		 * and yres_virtual/xres_virtual equal to number lesser than the
1159 		 * vc_font.height and yres/xres.
1160 		 * In the second call, the struct fb_var_screeninfo isn't
1161 		 * being modified by the underlying driver because of the
1162 		 * if above, and this causes the fbcon_display->vrows to become
1163 		 * negative and it eventually leads to out-of-bound
1164 		 * access by the imageblit function.
1165 		 * To give the correct values to the struct and to not have
1166 		 * to deal with possible errors from the code below, we call
1167 		 * the resize_screen here as well.
1168 		 */
1169 		return resize_screen(vc, new_cols, new_rows, from_user);
1170 	}
1171 
1172 	if (new_screen_size > KMALLOC_MAX_SIZE || !new_screen_size)
1173 		return -EINVAL;
1174 	newscreen = kzalloc(new_screen_size, GFP_USER);
1175 	if (!newscreen)
1176 		return -ENOMEM;
1177 
1178 	if (vc->vc_uni_lines) {
1179 		new_uniscr = vc_uniscr_alloc(new_cols, new_rows);
1180 		if (!new_uniscr) {
1181 			kfree(newscreen);
1182 			return -ENOMEM;
1183 		}
1184 	}
1185 
1186 	if (vc_is_sel(vc))
1187 		clear_selection();
1188 
1189 	old_rows = vc->vc_rows;
1190 	old_row_size = vc->vc_size_row;
1191 
1192 	err = resize_screen(vc, new_cols, new_rows, from_user);
1193 	if (err) {
1194 		kfree(newscreen);
1195 		vc_uniscr_free(new_uniscr);
1196 		return err;
1197 	}
1198 
1199 	vc->vc_rows = new_rows;
1200 	vc->vc_cols = new_cols;
1201 	vc->vc_size_row = new_row_size;
1202 	vc->vc_screenbuf_size = new_screen_size;
1203 
1204 	rlth = min(old_row_size, new_row_size);
1205 	rrem = new_row_size - rlth;
1206 	old_origin = vc->vc_origin;
1207 	new_origin = (long) newscreen;
1208 	new_scr_end = new_origin + new_screen_size;
1209 
1210 	if (vc->state.y > new_rows) {
1211 		if (old_rows - vc->state.y < new_rows) {
1212 			/*
1213 			 * Cursor near the bottom, copy contents from the
1214 			 * bottom of buffer
1215 			 */
1216 			first_copied_row = (old_rows - new_rows);
1217 		} else {
1218 			/*
1219 			 * Cursor is in no man's land, copy 1/2 screenful
1220 			 * from the top and bottom of cursor position
1221 			 */
1222 			first_copied_row = (vc->state.y - new_rows/2);
1223 		}
1224 		old_origin += first_copied_row * old_row_size;
1225 	} else
1226 		first_copied_row = 0;
1227 	end = old_origin + old_row_size * min(old_rows, new_rows);
1228 
1229 	vc_uniscr_copy_area(new_uniscr, new_cols, new_rows,
1230 			    vc->vc_uni_lines, rlth/2, first_copied_row,
1231 			    min(old_rows, new_rows));
1232 	vc_uniscr_set(vc, new_uniscr);
1233 
1234 	update_attr(vc);
1235 
1236 	while (old_origin < end) {
1237 		scr_memcpyw((unsigned short *) new_origin,
1238 			    (unsigned short *) old_origin, rlth);
1239 		if (rrem)
1240 			scr_memsetw((void *)(new_origin + rlth),
1241 				    vc->vc_video_erase_char, rrem);
1242 		old_origin += old_row_size;
1243 		new_origin += new_row_size;
1244 	}
1245 	if (new_scr_end > new_origin)
1246 		scr_memsetw((void *)new_origin, vc->vc_video_erase_char,
1247 			    new_scr_end - new_origin);
1248 	oldscreen = vc->vc_screenbuf;
1249 	vc->vc_screenbuf = newscreen;
1250 	vc->vc_screenbuf_size = new_screen_size;
1251 	set_origin(vc);
1252 	kfree(oldscreen);
1253 
1254 	/* do part of a reset_terminal() */
1255 	vc->vc_top = 0;
1256 	vc->vc_bottom = vc->vc_rows;
1257 	gotoxy(vc, vc->state.x, vc->state.y);
1258 	save_cur(vc);
1259 
1260 	if (tty) {
1261 		/* Rewrite the requested winsize data with the actual
1262 		   resulting sizes */
1263 		struct winsize ws;
1264 		memset(&ws, 0, sizeof(ws));
1265 		ws.ws_row = vc->vc_rows;
1266 		ws.ws_col = vc->vc_cols;
1267 		ws.ws_ypixel = vc->vc_scan_lines;
1268 		tty_do_resize(tty, &ws);
1269 	}
1270 
1271 	if (con_is_visible(vc))
1272 		update_screen(vc);
1273 	vt_event_post(VT_EVENT_RESIZE, vc->vc_num, vc->vc_num);
1274 	notify_update(vc);
1275 	return err;
1276 }
1277 
1278 /**
1279  * __vc_resize - resize a VT
1280  * @vc: virtual console
1281  * @cols: columns
1282  * @rows: rows
1283  * @from_user: invoked by a user?
1284  *
1285  * Resize a virtual console as seen from the console end of things. We use the
1286  * common vc_do_resize() method to update the structures.
1287  *
1288  * Locking: The caller must hold the console sem to protect console internals
1289  * and @vc->port.tty.
1290  */
1291 int __vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows,
1292 		bool from_user)
1293 {
1294 	return vc_do_resize(vc->port.tty, vc, cols, rows, from_user);
1295 }
1296 EXPORT_SYMBOL(__vc_resize);
1297 
1298 /**
1299  * vt_resize - resize a VT
1300  * @tty: tty to resize
1301  * @ws: winsize attributes
1302  *
1303  * Resize a virtual terminal. This is called by the tty layer as we register
1304  * our own handler for resizing. The mutual helper does all the actual work.
1305  *
1306  * Locking: Takes the console sem and the called methods then take the tty
1307  * termios_rwsem and the tty ctrl.lock in that order.
1308  */
1309 static int vt_resize(struct tty_struct *tty, struct winsize *ws)
1310 {
1311 	struct vc_data *vc = tty->driver_data;
1312 	int ret;
1313 
1314 	console_lock();
1315 	ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row, false);
1316 	console_unlock();
1317 	return ret;
1318 }
1319 
1320 struct vc_data *vc_deallocate(unsigned int currcons)
1321 {
1322 	struct vc_data *vc = NULL;
1323 
1324 	WARN_CONSOLE_UNLOCKED();
1325 
1326 	if (vc_cons_allocated(currcons)) {
1327 		struct vt_notifier_param param;
1328 
1329 		param.vc = vc = vc_cons[currcons].d;
1330 		atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, &param);
1331 		vcs_remove_sysfs(currcons);
1332 		visual_deinit(vc);
1333 		con_free_unimap(vc);
1334 		put_pid(vc->vt_pid);
1335 		vc_uniscr_set(vc, NULL);
1336 		kfree(vc->vc_screenbuf);
1337 		vc_cons[currcons].d = NULL;
1338 	}
1339 	return vc;
1340 }
1341 
1342 /*
1343  *	VT102 emulator
1344  */
1345 
1346 enum { EPecma = 0, EPdec, EPeq, EPgt, EPlt};
1347 
1348 #define set_kbd(vc, x)	vt_set_kbd_mode_bit((vc)->vc_num, (x))
1349 #define clr_kbd(vc, x)	vt_clr_kbd_mode_bit((vc)->vc_num, (x))
1350 #define is_kbd(vc, x)	vt_get_kbd_mode_bit((vc)->vc_num, (x))
1351 
1352 #define decarm		VC_REPEAT
1353 #define decckm		VC_CKMODE
1354 #define kbdapplic	VC_APPLIC
1355 #define lnm		VC_CRLF
1356 
1357 const unsigned char color_table[] = { 0, 4, 2, 6, 1, 5, 3, 7,
1358 				       8,12,10,14, 9,13,11,15 };
1359 EXPORT_SYMBOL(color_table);
1360 
1361 /* the default colour table, for VGA+ colour systems */
1362 unsigned char default_red[] = {
1363 	0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa,
1364 	0x55, 0xff, 0x55, 0xff, 0x55, 0xff, 0x55, 0xff
1365 };
1366 module_param_array(default_red, byte, NULL, S_IRUGO | S_IWUSR);
1367 EXPORT_SYMBOL(default_red);
1368 
1369 unsigned char default_grn[] = {
1370 	0x00, 0x00, 0xaa, 0x55, 0x00, 0x00, 0xaa, 0xaa,
1371 	0x55, 0x55, 0xff, 0xff, 0x55, 0x55, 0xff, 0xff
1372 };
1373 module_param_array(default_grn, byte, NULL, S_IRUGO | S_IWUSR);
1374 EXPORT_SYMBOL(default_grn);
1375 
1376 unsigned char default_blu[] = {
1377 	0x00, 0x00, 0x00, 0x00, 0xaa, 0xaa, 0xaa, 0xaa,
1378 	0x55, 0x55, 0x55, 0x55, 0xff, 0xff, 0xff, 0xff
1379 };
1380 module_param_array(default_blu, byte, NULL, S_IRUGO | S_IWUSR);
1381 EXPORT_SYMBOL(default_blu);
1382 
1383 /*
1384  * gotoxy() must verify all boundaries, because the arguments
1385  * might also be negative. If the given position is out of
1386  * bounds, the cursor is placed at the nearest margin.
1387  */
1388 static void gotoxy(struct vc_data *vc, int new_x, int new_y)
1389 {
1390 	int min_y, max_y;
1391 
1392 	if (new_x < 0)
1393 		vc->state.x = 0;
1394 	else {
1395 		if (new_x >= vc->vc_cols)
1396 			vc->state.x = vc->vc_cols - 1;
1397 		else
1398 			vc->state.x = new_x;
1399 	}
1400 
1401  	if (vc->vc_decom) {
1402 		min_y = vc->vc_top;
1403 		max_y = vc->vc_bottom;
1404 	} else {
1405 		min_y = 0;
1406 		max_y = vc->vc_rows;
1407 	}
1408 	if (new_y < min_y)
1409 		vc->state.y = min_y;
1410 	else if (new_y >= max_y)
1411 		vc->state.y = max_y - 1;
1412 	else
1413 		vc->state.y = new_y;
1414 	vc->vc_pos = vc->vc_origin + vc->state.y * vc->vc_size_row +
1415 		(vc->state.x << 1);
1416 	vc->vc_need_wrap = 0;
1417 }
1418 
1419 /* for absolute user moves, when decom is set */
1420 static void gotoxay(struct vc_data *vc, int new_x, int new_y)
1421 {
1422 	gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y);
1423 }
1424 
1425 void scrollback(struct vc_data *vc)
1426 {
1427 	scrolldelta(-(vc->vc_rows / 2));
1428 }
1429 
1430 void scrollfront(struct vc_data *vc, int lines)
1431 {
1432 	if (!lines)
1433 		lines = vc->vc_rows / 2;
1434 	scrolldelta(lines);
1435 }
1436 
1437 static void lf(struct vc_data *vc)
1438 {
1439     	/* don't scroll if above bottom of scrolling region, or
1440 	 * if below scrolling region
1441 	 */
1442 	if (vc->state.y + 1 == vc->vc_bottom)
1443 		con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_UP, 1);
1444 	else if (vc->state.y < vc->vc_rows - 1) {
1445 		vc->state.y++;
1446 		vc->vc_pos += vc->vc_size_row;
1447 	}
1448 	vc->vc_need_wrap = 0;
1449 	notify_write(vc, '\n');
1450 }
1451 
1452 static void ri(struct vc_data *vc)
1453 {
1454     	/* don't scroll if below top of scrolling region, or
1455 	 * if above scrolling region
1456 	 */
1457 	if (vc->state.y == vc->vc_top)
1458 		con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_DOWN, 1);
1459 	else if (vc->state.y > 0) {
1460 		vc->state.y--;
1461 		vc->vc_pos -= vc->vc_size_row;
1462 	}
1463 	vc->vc_need_wrap = 0;
1464 }
1465 
1466 static inline void cr(struct vc_data *vc)
1467 {
1468 	vc->vc_pos -= vc->state.x << 1;
1469 	vc->vc_need_wrap = vc->state.x = 0;
1470 	notify_write(vc, '\r');
1471 }
1472 
1473 static inline void bs(struct vc_data *vc)
1474 {
1475 	if (vc->state.x) {
1476 		vc->vc_pos -= 2;
1477 		vc->state.x--;
1478 		vc->vc_need_wrap = 0;
1479 		notify_write(vc, '\b');
1480 	}
1481 }
1482 
1483 static inline void del(struct vc_data *vc)
1484 {
1485 	/* ignored */
1486 }
1487 
1488 enum CSI_J {
1489 	CSI_J_CURSOR_TO_END	= 0,
1490 	CSI_J_START_TO_CURSOR	= 1,
1491 	CSI_J_VISIBLE		= 2,
1492 	CSI_J_FULL		= 3,
1493 };
1494 
1495 static void csi_J(struct vc_data *vc, enum CSI_J vpar)
1496 {
1497 	unsigned short *start;
1498 	unsigned int count;
1499 
1500 	switch (vpar) {
1501 	case CSI_J_CURSOR_TO_END:
1502 		vc_uniscr_clear_line(vc, vc->state.x,
1503 				     vc->vc_cols - vc->state.x);
1504 		vc_uniscr_clear_lines(vc, vc->state.y + 1,
1505 				      vc->vc_rows - vc->state.y - 1);
1506 		count = (vc->vc_scr_end - vc->vc_pos) >> 1;
1507 		start = (unsigned short *)vc->vc_pos;
1508 		break;
1509 	case CSI_J_START_TO_CURSOR:
1510 		vc_uniscr_clear_line(vc, 0, vc->state.x + 1);
1511 		vc_uniscr_clear_lines(vc, 0, vc->state.y);
1512 		count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1;
1513 		start = (unsigned short *)vc->vc_origin;
1514 		break;
1515 	case CSI_J_FULL:
1516 		flush_scrollback(vc);
1517 		fallthrough;
1518 	case CSI_J_VISIBLE:
1519 		vc_uniscr_clear_lines(vc, 0, vc->vc_rows);
1520 		count = vc->vc_cols * vc->vc_rows;
1521 		start = (unsigned short *)vc->vc_origin;
1522 		break;
1523 	default:
1524 		return;
1525 	}
1526 	scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1527 	if (con_should_update(vc))
1528 		do_update_region(vc, (unsigned long) start, count);
1529 	vc->vc_need_wrap = 0;
1530 }
1531 
1532 enum {
1533 	CSI_K_CURSOR_TO_LINEEND		= 0,
1534 	CSI_K_LINESTART_TO_CURSOR	= 1,
1535 	CSI_K_LINE			= 2,
1536 };
1537 
1538 static void csi_K(struct vc_data *vc)
1539 {
1540 	unsigned int count;
1541 	unsigned short *start = (unsigned short *)vc->vc_pos;
1542 	int offset;
1543 
1544 	switch (vc->vc_par[0]) {
1545 	case CSI_K_CURSOR_TO_LINEEND:
1546 		offset = 0;
1547 		count = vc->vc_cols - vc->state.x;
1548 		break;
1549 	case CSI_K_LINESTART_TO_CURSOR:
1550 		offset = -vc->state.x;
1551 		count = vc->state.x + 1;
1552 		break;
1553 	case CSI_K_LINE:
1554 		offset = -vc->state.x;
1555 		count = vc->vc_cols;
1556 		break;
1557 	default:
1558 		return;
1559 	}
1560 	vc_uniscr_clear_line(vc, vc->state.x + offset, count);
1561 	scr_memsetw(start + offset, vc->vc_video_erase_char, 2 * count);
1562 	vc->vc_need_wrap = 0;
1563 	if (con_should_update(vc))
1564 		do_update_region(vc, (unsigned long)(start + offset), count);
1565 }
1566 
1567 /* erase the following count positions */
1568 static void csi_X(struct vc_data *vc)
1569 {					  /* not vt100? */
1570 	unsigned int count = clamp(vc->vc_par[0], 1, vc->vc_cols - vc->state.x);
1571 
1572 	vc_uniscr_clear_line(vc, vc->state.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->state.y, vc->state.x, count);
1576 	vc->vc_need_wrap = 0;
1577 }
1578 
1579 static void default_attr(struct vc_data *vc)
1580 {
1581 	vc->state.intensity = VCI_NORMAL;
1582 	vc->state.italic = false;
1583 	vc->state.underline = false;
1584 	vc->state.reverse = false;
1585 	vc->state.blink = false;
1586 	vc->state.color = vc->vc_def_color;
1587 }
1588 
1589 struct rgb { u8 r; u8 g; u8 b; };
1590 
1591 static void rgb_from_256(unsigned 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 		i -= 16;
1603 		c->b = i % 6 * 255 / 6;
1604 		i /= 6;
1605 		c->g = i % 6 * 255 / 6;
1606 		i /= 6;
1607 		c->r = i     * 255 / 6;
1608 	} else                  /* Grayscale ramp. */
1609 		c->r = c->g = c->b = i * 10 - 2312;
1610 }
1611 
1612 static void rgb_foreground(struct vc_data *vc, const struct rgb *c)
1613 {
1614 	u8 hue = 0, max = max3(c->r, c->g, c->b);
1615 
1616 	if (c->r > max / 2)
1617 		hue |= 4;
1618 	if (c->g > max / 2)
1619 		hue |= 2;
1620 	if (c->b > max / 2)
1621 		hue |= 1;
1622 
1623 	if (hue == 7 && max <= 0x55) {
1624 		hue = 0;
1625 		vc->state.intensity = VCI_BOLD;
1626 	} else if (max > 0xaa)
1627 		vc->state.intensity = VCI_BOLD;
1628 	else
1629 		vc->state.intensity = VCI_NORMAL;
1630 
1631 	vc->state.color = (vc->state.color & 0xf0) | hue;
1632 }
1633 
1634 static void rgb_background(struct vc_data *vc, const struct rgb *c)
1635 {
1636 	/* For backgrounds, err on the dark side. */
1637 	vc->state.color = (vc->state.color & 0x0f)
1638 		| (c->r&0x80) >> 1 | (c->g&0x80) >> 2 | (c->b&0x80) >> 3;
1639 }
1640 
1641 /*
1642  * ITU T.416 Higher colour modes. They break the usual properties of SGR codes
1643  * and thus need to be detected and ignored by hand. That standard also
1644  * wants : rather than ; as separators but sequences containing : are currently
1645  * completely ignored by the parser.
1646  *
1647  * Subcommands 3 (CMY) and 4 (CMYK) are so insane there's no point in
1648  * supporting them.
1649  */
1650 static int vc_t416_color(struct vc_data *vc, int i,
1651 		void(*set_color)(struct vc_data *vc, const struct rgb *c))
1652 {
1653 	struct rgb c;
1654 
1655 	i++;
1656 	if (i > vc->vc_npar)
1657 		return i;
1658 
1659 	if (vc->vc_par[i] == 5 && i + 1 <= vc->vc_npar) {
1660 		/* 256 colours */
1661 		i++;
1662 		rgb_from_256(vc->vc_par[i], &c);
1663 	} else if (vc->vc_par[i] == 2 && i + 3 <= vc->vc_npar) {
1664 		/* 24 bit */
1665 		c.r = vc->vc_par[i + 1];
1666 		c.g = vc->vc_par[i + 2];
1667 		c.b = vc->vc_par[i + 3];
1668 		i += 3;
1669 	} else
1670 		return i;
1671 
1672 	set_color(vc, &c);
1673 
1674 	return i;
1675 }
1676 
1677 enum {
1678 	CSI_m_DEFAULT			= 0,
1679 	CSI_m_BOLD			= 1,
1680 	CSI_m_HALF_BRIGHT		= 2,
1681 	CSI_m_ITALIC			= 3,
1682 	CSI_m_UNDERLINE			= 4,
1683 	CSI_m_BLINK			= 5,
1684 	CSI_m_REVERSE			= 7,
1685 	CSI_m_PRI_FONT			= 10,
1686 	CSI_m_ALT_FONT1			= 11,
1687 	CSI_m_ALT_FONT2			= 12,
1688 	CSI_m_DOUBLE_UNDERLINE		= 21,
1689 	CSI_m_NORMAL_INTENSITY		= 22,
1690 	CSI_m_NO_ITALIC			= 23,
1691 	CSI_m_NO_UNDERLINE		= 24,
1692 	CSI_m_NO_BLINK			= 25,
1693 	CSI_m_NO_REVERSE		= 27,
1694 	CSI_m_FG_COLOR_BEG		= 30,
1695 	CSI_m_FG_COLOR_END		= 37,
1696 	CSI_m_FG_COLOR			= 38,
1697 	CSI_m_DEFAULT_FG_COLOR		= 39,
1698 	CSI_m_BG_COLOR_BEG		= 40,
1699 	CSI_m_BG_COLOR_END		= 47,
1700 	CSI_m_BG_COLOR			= 48,
1701 	CSI_m_DEFAULT_BG_COLOR		= 49,
1702 	CSI_m_BRIGHT_FG_COLOR_BEG	= 90,
1703 	CSI_m_BRIGHT_FG_COLOR_END	= 97,
1704 	CSI_m_BRIGHT_FG_COLOR_OFF	= CSI_m_BRIGHT_FG_COLOR_BEG - CSI_m_FG_COLOR_BEG,
1705 	CSI_m_BRIGHT_BG_COLOR_BEG	= 100,
1706 	CSI_m_BRIGHT_BG_COLOR_END	= 107,
1707 	CSI_m_BRIGHT_BG_COLOR_OFF	= CSI_m_BRIGHT_BG_COLOR_BEG - CSI_m_BG_COLOR_BEG,
1708 };
1709 
1710 /* console_lock is held */
1711 static void csi_m(struct vc_data *vc)
1712 {
1713 	int i;
1714 
1715 	for (i = 0; i <= vc->vc_npar; i++)
1716 		switch (vc->vc_par[i]) {
1717 		case CSI_m_DEFAULT:	/* all attributes off */
1718 			default_attr(vc);
1719 			break;
1720 		case CSI_m_BOLD:
1721 			vc->state.intensity = VCI_BOLD;
1722 			break;
1723 		case CSI_m_HALF_BRIGHT:
1724 			vc->state.intensity = VCI_HALF_BRIGHT;
1725 			break;
1726 		case CSI_m_ITALIC:
1727 			vc->state.italic = true;
1728 			break;
1729 		case CSI_m_DOUBLE_UNDERLINE:
1730 			/*
1731 			 * No console drivers support double underline, so
1732 			 * convert it to a single underline.
1733 			 */
1734 		case CSI_m_UNDERLINE:
1735 			vc->state.underline = true;
1736 			break;
1737 		case CSI_m_BLINK:
1738 			vc->state.blink = true;
1739 			break;
1740 		case CSI_m_REVERSE:
1741 			vc->state.reverse = true;
1742 			break;
1743 		case CSI_m_PRI_FONT: /* ANSI X3.64-1979 (SCO-ish?)
1744 			  * Select primary font, don't display control chars if
1745 			  * defined, don't set bit 8 on output.
1746 			  */
1747 			vc->vc_translate = set_translate(vc->state.Gx_charset[vc->state.charset], vc);
1748 			vc->vc_disp_ctrl = 0;
1749 			vc->vc_toggle_meta = 0;
1750 			break;
1751 		case CSI_m_ALT_FONT1: /* ANSI X3.64-1979 (SCO-ish?)
1752 			  * Select first alternate font, lets chars < 32 be
1753 			  * displayed as ROM chars.
1754 			  */
1755 			vc->vc_translate = set_translate(IBMPC_MAP, vc);
1756 			vc->vc_disp_ctrl = 1;
1757 			vc->vc_toggle_meta = 0;
1758 			break;
1759 		case CSI_m_ALT_FONT2: /* ANSI X3.64-1979 (SCO-ish?)
1760 			  * Select second alternate font, toggle high bit
1761 			  * before displaying as ROM char.
1762 			  */
1763 			vc->vc_translate = set_translate(IBMPC_MAP, vc);
1764 			vc->vc_disp_ctrl = 1;
1765 			vc->vc_toggle_meta = 1;
1766 			break;
1767 		case CSI_m_NORMAL_INTENSITY:
1768 			vc->state.intensity = VCI_NORMAL;
1769 			break;
1770 		case CSI_m_NO_ITALIC:
1771 			vc->state.italic = false;
1772 			break;
1773 		case CSI_m_NO_UNDERLINE:
1774 			vc->state.underline = false;
1775 			break;
1776 		case CSI_m_NO_BLINK:
1777 			vc->state.blink = false;
1778 			break;
1779 		case CSI_m_NO_REVERSE:
1780 			vc->state.reverse = false;
1781 			break;
1782 		case CSI_m_FG_COLOR:
1783 			i = vc_t416_color(vc, i, rgb_foreground);
1784 			break;
1785 		case CSI_m_BG_COLOR:
1786 			i = vc_t416_color(vc, i, rgb_background);
1787 			break;
1788 		case CSI_m_DEFAULT_FG_COLOR:
1789 			vc->state.color = (vc->vc_def_color & 0x0f) |
1790 				(vc->state.color & 0xf0);
1791 			break;
1792 		case CSI_m_DEFAULT_BG_COLOR:
1793 			vc->state.color = (vc->vc_def_color & 0xf0) |
1794 				(vc->state.color & 0x0f);
1795 			break;
1796 		case CSI_m_BRIGHT_FG_COLOR_BEG ... CSI_m_BRIGHT_FG_COLOR_END:
1797 			vc->state.intensity = VCI_BOLD;
1798 			vc->vc_par[i] -= CSI_m_BRIGHT_FG_COLOR_OFF;
1799 			fallthrough;
1800 		case CSI_m_FG_COLOR_BEG ... CSI_m_FG_COLOR_END:
1801 			vc->vc_par[i] -= CSI_m_FG_COLOR_BEG;
1802 			vc->state.color = color_table[vc->vc_par[i]] |
1803 				(vc->state.color & 0xf0);
1804 			break;
1805 		case CSI_m_BRIGHT_BG_COLOR_BEG ... CSI_m_BRIGHT_BG_COLOR_END:
1806 			vc->vc_par[i] -= CSI_m_BRIGHT_BG_COLOR_OFF;
1807 			fallthrough;
1808 		case CSI_m_BG_COLOR_BEG ... CSI_m_BG_COLOR_END:
1809 			vc->vc_par[i] -= CSI_m_BG_COLOR_BEG;
1810 			vc->state.color = (color_table[vc->vc_par[i]] << 4) |
1811 				(vc->state.color & 0x0f);
1812 			break;
1813 		}
1814 	update_attr(vc);
1815 }
1816 
1817 static void respond_string(const char *p, size_t len, struct tty_port *port)
1818 {
1819 	tty_insert_flip_string(port, p, len);
1820 	tty_flip_buffer_push(port);
1821 }
1822 
1823 static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
1824 {
1825 	char buf[40];
1826 	int len;
1827 
1828 	len = sprintf(buf, "\033[%d;%dR", vc->state.y +
1829 			(vc->vc_decom ? vc->vc_top + 1 : 1),
1830 			vc->state.x + 1);
1831 	respond_string(buf, len, tty->port);
1832 }
1833 
1834 static inline void status_report(struct tty_struct *tty)
1835 {
1836 	static const char teminal_ok[] = "\033[0n";
1837 
1838 	respond_string(teminal_ok, strlen(teminal_ok), tty->port);
1839 }
1840 
1841 static inline void respond_ID(struct tty_struct *tty)
1842 {
1843 	/* terminal answer to an ESC-Z or csi0c query. */
1844 	static const char vt102_id[] = "\033[?6c";
1845 
1846 	respond_string(vt102_id, strlen(vt102_id), tty->port);
1847 }
1848 
1849 void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
1850 {
1851 	char buf[8];
1852 	int len;
1853 
1854 	len = sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt),
1855 			(char)('!' + mrx), (char)('!' + mry));
1856 	respond_string(buf, len, tty->port);
1857 }
1858 
1859 /* invoked via ioctl(TIOCLINUX) and through set_selection_user */
1860 int mouse_reporting(void)
1861 {
1862 	return vc_cons[fg_console].d->vc_report_mouse;
1863 }
1864 
1865 enum {
1866 	CSI_DEC_hl_CURSOR_KEYS	= 1,	/* CKM: cursor keys send ^[Ox/^[[x */
1867 	CSI_DEC_hl_132_COLUMNS	= 3,	/* COLM: 80/132 mode switch */
1868 	CSI_DEC_hl_REVERSE_VIDEO = 5,	/* SCNM */
1869 	CSI_DEC_hl_ORIGIN_MODE	= 6,	/* OM: origin relative/absolute */
1870 	CSI_DEC_hl_AUTOWRAP	= 7,	/* AWM */
1871 	CSI_DEC_hl_AUTOREPEAT	= 8,	/* ARM */
1872 	CSI_DEC_hl_MOUSE_X10	= 9,
1873 	CSI_DEC_hl_SHOW_CURSOR	= 25,	/* TCEM */
1874 	CSI_DEC_hl_MOUSE_VT200	= 1000,
1875 };
1876 
1877 /* console_lock is held */
1878 static void csi_DEC_hl(struct vc_data *vc, bool on_off)
1879 {
1880 	unsigned int i;
1881 
1882 	for (i = 0; i <= vc->vc_npar; i++)
1883 		switch (vc->vc_par[i]) {
1884 		case CSI_DEC_hl_CURSOR_KEYS:
1885 			if (on_off)
1886 				set_kbd(vc, decckm);
1887 			else
1888 				clr_kbd(vc, decckm);
1889 			break;
1890 		case CSI_DEC_hl_132_COLUMNS:	/* unimplemented */
1891 #if 0
1892 			vc_resize(deccolm ? 132 : 80, vc->vc_rows);
1893 			/* this alone does not suffice; some user mode
1894 			   utility has to change the hardware regs */
1895 #endif
1896 			break;
1897 		case CSI_DEC_hl_REVERSE_VIDEO:
1898 			if (vc->vc_decscnm != on_off) {
1899 				vc->vc_decscnm = on_off;
1900 				invert_screen(vc, 0, vc->vc_screenbuf_size,
1901 					      false);
1902 				update_attr(vc);
1903 			}
1904 			break;
1905 		case CSI_DEC_hl_ORIGIN_MODE:
1906 			vc->vc_decom = on_off;
1907 			gotoxay(vc, 0, 0);
1908 			break;
1909 		case CSI_DEC_hl_AUTOWRAP:
1910 			vc->vc_decawm = on_off;
1911 			break;
1912 		case CSI_DEC_hl_AUTOREPEAT:
1913 			if (on_off)
1914 				set_kbd(vc, decarm);
1915 			else
1916 				clr_kbd(vc, decarm);
1917 			break;
1918 		case CSI_DEC_hl_MOUSE_X10:
1919 			vc->vc_report_mouse = on_off ? 1 : 0;
1920 			break;
1921 		case CSI_DEC_hl_SHOW_CURSOR:
1922 			vc->vc_deccm = on_off;
1923 			break;
1924 		case CSI_DEC_hl_MOUSE_VT200:
1925 			vc->vc_report_mouse = on_off ? 2 : 0;
1926 			break;
1927 		}
1928 }
1929 
1930 enum {
1931 	CSI_hl_DISPLAY_CTRL	= 3,	/* handle ansi control chars */
1932 	CSI_hl_INSERT		= 4,	/* IRM: insert/replace */
1933 	CSI_hl_AUTO_NL		= 20,	/* LNM: Enter == CrLf/Lf */
1934 };
1935 
1936 /* console_lock is held */
1937 static void csi_hl(struct vc_data *vc, bool on_off)
1938 {
1939 	unsigned int i;
1940 
1941 	for (i = 0; i <= vc->vc_npar; i++)
1942 		switch (vc->vc_par[i]) {	/* ANSI modes set/reset */
1943 		case CSI_hl_DISPLAY_CTRL:
1944 			vc->vc_disp_ctrl = on_off;
1945 			break;
1946 		case CSI_hl_INSERT:
1947 			vc->vc_decim = on_off;
1948 			break;
1949 		case CSI_hl_AUTO_NL:
1950 			if (on_off)
1951 				set_kbd(vc, lnm);
1952 			else
1953 				clr_kbd(vc, lnm);
1954 			break;
1955 		}
1956 }
1957 
1958 enum CSI_right_square_bracket {
1959 	CSI_RSB_COLOR_FOR_UNDERLINE		= 1,
1960 	CSI_RSB_COLOR_FOR_HALF_BRIGHT		= 2,
1961 	CSI_RSB_MAKE_CUR_COLOR_DEFAULT		= 8,
1962 	CSI_RSB_BLANKING_INTERVAL		= 9,
1963 	CSI_RSB_BELL_FREQUENCY			= 10,
1964 	CSI_RSB_BELL_DURATION			= 11,
1965 	CSI_RSB_BRING_CONSOLE_TO_FRONT		= 12,
1966 	CSI_RSB_UNBLANK				= 13,
1967 	CSI_RSB_VESA_OFF_INTERVAL		= 14,
1968 	CSI_RSB_BRING_PREV_CONSOLE_TO_FRONT	= 15,
1969 	CSI_RSB_CURSOR_BLINK_INTERVAL		= 16,
1970 };
1971 
1972 /*
1973  * csi_RSB - csi+] (Right Square Bracket) handler
1974  *
1975  * These are linux console private sequences.
1976  *
1977  * console_lock is held
1978  */
1979 static void csi_RSB(struct vc_data *vc)
1980 {
1981 	switch (vc->vc_par[0]) {
1982 	case CSI_RSB_COLOR_FOR_UNDERLINE:
1983 		if (vc->vc_can_do_color && vc->vc_par[1] < 16) {
1984 			vc->vc_ulcolor = color_table[vc->vc_par[1]];
1985 			if (vc->state.underline)
1986 				update_attr(vc);
1987 		}
1988 		break;
1989 	case CSI_RSB_COLOR_FOR_HALF_BRIGHT:
1990 		if (vc->vc_can_do_color && vc->vc_par[1] < 16) {
1991 			vc->vc_halfcolor = color_table[vc->vc_par[1]];
1992 			if (vc->state.intensity == VCI_HALF_BRIGHT)
1993 				update_attr(vc);
1994 		}
1995 		break;
1996 	case CSI_RSB_MAKE_CUR_COLOR_DEFAULT:
1997 		vc->vc_def_color = vc->vc_attr;
1998 		if (vc->vc_hi_font_mask == 0x100)
1999 			vc->vc_def_color >>= 1;
2000 		default_attr(vc);
2001 		update_attr(vc);
2002 		break;
2003 	case CSI_RSB_BLANKING_INTERVAL:
2004 		blankinterval = min(vc->vc_par[1], 60U) * 60;
2005 		poke_blanked_console();
2006 		break;
2007 	case CSI_RSB_BELL_FREQUENCY:
2008 		if (vc->vc_npar >= 1)
2009 			vc->vc_bell_pitch = vc->vc_par[1];
2010 		else
2011 			vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
2012 		break;
2013 	case CSI_RSB_BELL_DURATION:
2014 		if (vc->vc_npar >= 1)
2015 			vc->vc_bell_duration = (vc->vc_par[1] < 2000) ?
2016 				msecs_to_jiffies(vc->vc_par[1]) : 0;
2017 		else
2018 			vc->vc_bell_duration = DEFAULT_BELL_DURATION;
2019 		break;
2020 	case CSI_RSB_BRING_CONSOLE_TO_FRONT:
2021 		if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1))
2022 			set_console(vc->vc_par[1] - 1);
2023 		break;
2024 	case CSI_RSB_UNBLANK:
2025 		poke_blanked_console();
2026 		break;
2027 	case CSI_RSB_VESA_OFF_INTERVAL:
2028 		vesa_off_interval = min(vc->vc_par[1], 60U) * 60 * HZ;
2029 		break;
2030 	case CSI_RSB_BRING_PREV_CONSOLE_TO_FRONT:
2031 		set_console(last_console);
2032 		break;
2033 	case CSI_RSB_CURSOR_BLINK_INTERVAL:
2034 		if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 &&
2035 				vc->vc_par[1] <= USHRT_MAX)
2036 			vc->vc_cur_blink_ms = vc->vc_par[1];
2037 		else
2038 			vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
2039 		break;
2040 	}
2041 }
2042 
2043 /* console_lock is held */
2044 static void csi_at(struct vc_data *vc, unsigned int nr)
2045 {
2046 	nr = clamp(nr, 1, vc->vc_cols - vc->state.x);
2047 	insert_char(vc, nr);
2048 }
2049 
2050 /* console_lock is held */
2051 static void csi_L(struct vc_data *vc)
2052 {
2053 	unsigned int nr = clamp(vc->vc_par[0], 1, vc->vc_rows - vc->state.y);
2054 
2055 	con_scroll(vc, vc->state.y, vc->vc_bottom, SM_DOWN, nr);
2056 	vc->vc_need_wrap = 0;
2057 }
2058 
2059 /* console_lock is held */
2060 static void csi_P(struct vc_data *vc)
2061 {
2062 	unsigned int nr = clamp(vc->vc_par[0], 1, vc->vc_cols - vc->state.x);
2063 
2064 	delete_char(vc, nr);
2065 }
2066 
2067 /* console_lock is held */
2068 static void csi_M(struct vc_data *vc)
2069 {
2070 	unsigned int nr = clamp(vc->vc_par[0], 1, vc->vc_rows - vc->state.y);
2071 
2072 	con_scroll(vc, vc->state.y, vc->vc_bottom, SM_UP, nr);
2073 	vc->vc_need_wrap = 0;
2074 }
2075 
2076 /* console_lock is held (except via vc_init->reset_terminal */
2077 static void save_cur(struct vc_data *vc)
2078 {
2079 	memcpy(&vc->saved_state, &vc->state, sizeof(vc->state));
2080 }
2081 
2082 /* console_lock is held */
2083 static void restore_cur(struct vc_data *vc)
2084 {
2085 	memcpy(&vc->state, &vc->saved_state, sizeof(vc->state));
2086 
2087 	gotoxy(vc, vc->state.x, vc->state.y);
2088 	vc->vc_translate = set_translate(vc->state.Gx_charset[vc->state.charset],
2089 			vc);
2090 	update_attr(vc);
2091 	vc->vc_need_wrap = 0;
2092 }
2093 
2094 /**
2095  * enum vc_ctl_state - control characters state of a vt
2096  *
2097  * @ESnormal:		initial state, no control characters parsed
2098  * @ESesc:		ESC parsed
2099  * @ESsquare:		CSI parsed -- modifiers/parameters/ctrl chars expected
2100  * @ESgetpars:		CSI parsed -- parameters/ctrl chars expected
2101  * @ESfunckey:		CSI [ parsed
2102  * @EShash:		ESC # parsed
2103  * @ESsetG0:		ESC ( parsed
2104  * @ESsetG1:		ESC ) parsed
2105  * @ESpercent:		ESC % parsed
2106  * @EScsiignore:	CSI [0x20-0x3f] parsed
2107  * @ESnonstd:		OSC parsed
2108  * @ESpalette:		OSC P parsed
2109  * @ESosc:		OSC [0-9] parsed
2110  * @ESANSI_first:	first state for ignoring ansi control sequences
2111  * @ESapc:		ESC _ parsed
2112  * @ESpm:		ESC ^ parsed
2113  * @ESdcs:		ESC P parsed
2114  * @ESANSI_last:	last state for ignoring ansi control sequences
2115  */
2116 enum vc_ctl_state {
2117 	ESnormal,
2118 	ESesc,
2119 	ESsquare,
2120 	ESgetpars,
2121 	ESfunckey,
2122 	EShash,
2123 	ESsetG0,
2124 	ESsetG1,
2125 	ESpercent,
2126 	EScsiignore,
2127 	ESnonstd,
2128 	ESpalette,
2129 	ESosc,
2130 	ESANSI_first = ESosc,
2131 	ESapc,
2132 	ESpm,
2133 	ESdcs,
2134 	ESANSI_last = ESdcs,
2135 };
2136 
2137 /* console_lock is held (except via vc_init()) */
2138 static void reset_terminal(struct vc_data *vc, int do_clear)
2139 {
2140 	unsigned int i;
2141 
2142 	vc->vc_top		= 0;
2143 	vc->vc_bottom		= vc->vc_rows;
2144 	vc->vc_state		= ESnormal;
2145 	vc->vc_priv		= EPecma;
2146 	vc->vc_translate	= set_translate(LAT1_MAP, vc);
2147 	vc->state.Gx_charset[0]	= LAT1_MAP;
2148 	vc->state.Gx_charset[1]	= GRAF_MAP;
2149 	vc->state.charset	= 0;
2150 	vc->vc_need_wrap	= 0;
2151 	vc->vc_report_mouse	= 0;
2152 	vc->vc_utf              = default_utf8;
2153 	vc->vc_utf_count	= 0;
2154 
2155 	vc->vc_disp_ctrl	= 0;
2156 	vc->vc_toggle_meta	= 0;
2157 
2158 	vc->vc_decscnm		= 0;
2159 	vc->vc_decom		= 0;
2160 	vc->vc_decawm		= 1;
2161 	vc->vc_deccm		= global_cursor_default;
2162 	vc->vc_decim		= 0;
2163 
2164 	vt_reset_keyboard(vc->vc_num);
2165 
2166 	vc->vc_cursor_type = cur_default;
2167 	vc->vc_complement_mask = vc->vc_s_complement_mask;
2168 
2169 	default_attr(vc);
2170 	update_attr(vc);
2171 
2172 	bitmap_zero(vc->vc_tab_stop, VC_TABSTOPS_COUNT);
2173 	for (i = 0; i < VC_TABSTOPS_COUNT; i += 8)
2174 		set_bit(i, vc->vc_tab_stop);
2175 
2176 	vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
2177 	vc->vc_bell_duration = DEFAULT_BELL_DURATION;
2178 	vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
2179 
2180 	gotoxy(vc, 0, 0);
2181 	save_cur(vc);
2182 	if (do_clear)
2183 	    csi_J(vc, CSI_J_VISIBLE);
2184 }
2185 
2186 static void vc_setGx(struct vc_data *vc, unsigned int which, u8 c)
2187 {
2188 	unsigned char *charset = &vc->state.Gx_charset[which];
2189 
2190 	switch (c) {
2191 	case '0':
2192 		*charset = GRAF_MAP;
2193 		break;
2194 	case 'B':
2195 		*charset = LAT1_MAP;
2196 		break;
2197 	case 'U':
2198 		*charset = IBMPC_MAP;
2199 		break;
2200 	case 'K':
2201 		*charset = USER_MAP;
2202 		break;
2203 	}
2204 
2205 	if (vc->state.charset == which)
2206 		vc->vc_translate = set_translate(*charset, vc);
2207 }
2208 
2209 static bool ansi_control_string(enum vc_ctl_state state)
2210 {
2211 	return state >= ESANSI_first && state <= ESANSI_last;
2212 }
2213 
2214 enum {
2215 	ASCII_NULL		= 0,
2216 	ASCII_BELL		= 7,
2217 	ASCII_BACKSPACE		= 8,
2218 	ASCII_IGNORE_FIRST	= ASCII_BACKSPACE,
2219 	ASCII_HTAB		= 9,
2220 	ASCII_LINEFEED		= 10,
2221 	ASCII_VTAB		= 11,
2222 	ASCII_FORMFEED		= 12,
2223 	ASCII_CAR_RET		= 13,
2224 	ASCII_IGNORE_LAST	= ASCII_CAR_RET,
2225 	ASCII_SHIFTOUT		= 14,
2226 	ASCII_SHIFTIN		= 15,
2227 	ASCII_CANCEL		= 24,
2228 	ASCII_SUBSTITUTE	= 26,
2229 	ASCII_ESCAPE		= 27,
2230 	ASCII_CSI_IGNORE_FIRST	= ' ', /* 0x2x, 0x3a and 0x3c - 0x3f */
2231 	ASCII_CSI_IGNORE_LAST	= '?',
2232 	ASCII_DEL		= 127,
2233 	ASCII_EXT_CSI		= 128 + ASCII_ESCAPE,
2234 };
2235 
2236 /*
2237  * Handle ascii characters in control sequences and change states accordingly.
2238  * E.g. ESC sets the state of vc to ESesc.
2239  *
2240  * Returns: true if @c handled.
2241  */
2242 static bool handle_ascii(struct tty_struct *tty, struct vc_data *vc, u8 c)
2243 {
2244 	switch (c) {
2245 	case ASCII_NULL:
2246 		return true;
2247 	case ASCII_BELL:
2248 		if (ansi_control_string(vc->vc_state))
2249 			vc->vc_state = ESnormal;
2250 		else if (vc->vc_bell_duration)
2251 			kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration);
2252 		return true;
2253 	case ASCII_BACKSPACE:
2254 		bs(vc);
2255 		return true;
2256 	case ASCII_HTAB:
2257 		vc->vc_pos -= (vc->state.x << 1);
2258 
2259 		vc->state.x = find_next_bit(vc->vc_tab_stop,
2260 				min(vc->vc_cols - 1, VC_TABSTOPS_COUNT),
2261 				vc->state.x + 1);
2262 		if (vc->state.x >= VC_TABSTOPS_COUNT)
2263 			vc->state.x = vc->vc_cols - 1;
2264 
2265 		vc->vc_pos += (vc->state.x << 1);
2266 		notify_write(vc, '\t');
2267 		return true;
2268 	case ASCII_LINEFEED:
2269 	case ASCII_VTAB:
2270 	case ASCII_FORMFEED:
2271 		lf(vc);
2272 		if (!is_kbd(vc, lnm))
2273 			return true;
2274 		fallthrough;
2275 	case ASCII_CAR_RET:
2276 		cr(vc);
2277 		return true;
2278 	case ASCII_SHIFTOUT:
2279 		vc->state.charset = 1;
2280 		vc->vc_translate = set_translate(vc->state.Gx_charset[1], vc);
2281 		vc->vc_disp_ctrl = 1;
2282 		return true;
2283 	case ASCII_SHIFTIN:
2284 		vc->state.charset = 0;
2285 		vc->vc_translate = set_translate(vc->state.Gx_charset[0], vc);
2286 		vc->vc_disp_ctrl = 0;
2287 		return true;
2288 	case ASCII_CANCEL:
2289 	case ASCII_SUBSTITUTE:
2290 		vc->vc_state = ESnormal;
2291 		return true;
2292 	case ASCII_ESCAPE:
2293 		vc->vc_state = ESesc;
2294 		return true;
2295 	case ASCII_DEL:
2296 		del(vc);
2297 		return true;
2298 	case ASCII_EXT_CSI:
2299 		vc->vc_state = ESsquare;
2300 		return true;
2301 	}
2302 
2303 	return false;
2304 }
2305 
2306 /*
2307  * Handle a character (@c) following an ESC (when @vc is in the ESesc state).
2308  * E.g. previous ESC with @c == '[' here yields the ESsquare state (that is:
2309  * CSI).
2310  */
2311 static void handle_esc(struct tty_struct *tty, struct vc_data *vc, u8 c)
2312 {
2313 	vc->vc_state = ESnormal;
2314 	switch (c) {
2315 	case '[':
2316 		vc->vc_state = ESsquare;
2317 		break;
2318 	case ']':
2319 		vc->vc_state = ESnonstd;
2320 		break;
2321 	case '_':
2322 		vc->vc_state = ESapc;
2323 		break;
2324 	case '^':
2325 		vc->vc_state = ESpm;
2326 		break;
2327 	case '%':
2328 		vc->vc_state = ESpercent;
2329 		break;
2330 	case 'E':
2331 		cr(vc);
2332 		lf(vc);
2333 		break;
2334 	case 'M':
2335 		ri(vc);
2336 		break;
2337 	case 'D':
2338 		lf(vc);
2339 		break;
2340 	case 'H':
2341 		if (vc->state.x < VC_TABSTOPS_COUNT)
2342 			set_bit(vc->state.x, vc->vc_tab_stop);
2343 		break;
2344 	case 'P':
2345 		vc->vc_state = ESdcs;
2346 		break;
2347 	case 'Z':
2348 		respond_ID(tty);
2349 		break;
2350 	case '7':
2351 		save_cur(vc);
2352 		break;
2353 	case '8':
2354 		restore_cur(vc);
2355 		break;
2356 	case '(':
2357 		vc->vc_state = ESsetG0;
2358 		break;
2359 	case ')':
2360 		vc->vc_state = ESsetG1;
2361 		break;
2362 	case '#':
2363 		vc->vc_state = EShash;
2364 		break;
2365 	case 'c':
2366 		reset_terminal(vc, 1);
2367 		break;
2368 	case '>':  /* Numeric keypad */
2369 		clr_kbd(vc, kbdapplic);
2370 		break;
2371 	case '=':  /* Appl. keypad */
2372 		set_kbd(vc, kbdapplic);
2373 		break;
2374 	}
2375 }
2376 
2377 /*
2378  * Handle special DEC control sequences ("ESC [ ? parameters char"). Parameters
2379  * are in @vc->vc_par and the char is in @c here.
2380  */
2381 static void csi_DEC(struct tty_struct *tty, struct vc_data *vc, u8 c)
2382 {
2383 	switch (c) {
2384 	case 'h':
2385 		csi_DEC_hl(vc, true);
2386 		break;
2387 	case 'l':
2388 		csi_DEC_hl(vc, false);
2389 		break;
2390 	case 'c':
2391 		if (vc->vc_par[0])
2392 			vc->vc_cursor_type = CUR_MAKE(vc->vc_par[0],
2393 						      vc->vc_par[1],
2394 						      vc->vc_par[2]);
2395 		else
2396 			vc->vc_cursor_type = cur_default;
2397 		break;
2398 	case 'm':
2399 		clear_selection();
2400 		if (vc->vc_par[0])
2401 			vc->vc_complement_mask = vc->vc_par[0] << 8 | vc->vc_par[1];
2402 		else
2403 			vc->vc_complement_mask = vc->vc_s_complement_mask;
2404 		break;
2405 	case 'n':
2406 		if (vc->vc_par[0] == 5)
2407 			status_report(tty);
2408 		else if (vc->vc_par[0] == 6)
2409 			cursor_report(vc, tty);
2410 		break;
2411 	}
2412 }
2413 
2414 /*
2415  * Handle Control Sequence Introducer control characters. That is
2416  * "ESC [ parameters char". Parameters are in @vc->vc_par and the char is in
2417  * @c here.
2418  */
2419 static void csi_ECMA(struct tty_struct *tty, struct vc_data *vc, u8 c)
2420 {
2421 	switch (c) {
2422 	case 'G':
2423 	case '`':
2424 		if (vc->vc_par[0])
2425 			vc->vc_par[0]--;
2426 		gotoxy(vc, vc->vc_par[0], vc->state.y);
2427 		break;
2428 	case 'A':
2429 		if (!vc->vc_par[0])
2430 			vc->vc_par[0]++;
2431 		gotoxy(vc, vc->state.x, vc->state.y - vc->vc_par[0]);
2432 		break;
2433 	case 'B':
2434 	case 'e':
2435 		if (!vc->vc_par[0])
2436 			vc->vc_par[0]++;
2437 		gotoxy(vc, vc->state.x, vc->state.y + vc->vc_par[0]);
2438 		break;
2439 	case 'C':
2440 	case 'a':
2441 		if (!vc->vc_par[0])
2442 			vc->vc_par[0]++;
2443 		gotoxy(vc, vc->state.x + vc->vc_par[0], vc->state.y);
2444 		break;
2445 	case 'D':
2446 		if (!vc->vc_par[0])
2447 			vc->vc_par[0]++;
2448 		gotoxy(vc, vc->state.x - vc->vc_par[0], vc->state.y);
2449 		break;
2450 	case 'E':
2451 		if (!vc->vc_par[0])
2452 			vc->vc_par[0]++;
2453 		gotoxy(vc, 0, vc->state.y + vc->vc_par[0]);
2454 		break;
2455 	case 'F':
2456 		if (!vc->vc_par[0])
2457 			vc->vc_par[0]++;
2458 		gotoxy(vc, 0, vc->state.y - vc->vc_par[0]);
2459 		break;
2460 	case 'd':
2461 		if (vc->vc_par[0])
2462 			vc->vc_par[0]--;
2463 		gotoxay(vc, vc->state.x ,vc->vc_par[0]);
2464 		break;
2465 	case 'H':
2466 	case 'f':
2467 		if (vc->vc_par[0])
2468 			vc->vc_par[0]--;
2469 		if (vc->vc_par[1])
2470 			vc->vc_par[1]--;
2471 		gotoxay(vc, vc->vc_par[1], vc->vc_par[0]);
2472 		break;
2473 	case 'J':
2474 		csi_J(vc, vc->vc_par[0]);
2475 		break;
2476 	case 'K':
2477 		csi_K(vc);
2478 		break;
2479 	case 'L':
2480 		csi_L(vc);
2481 		break;
2482 	case 'M':
2483 		csi_M(vc);
2484 		break;
2485 	case 'P':
2486 		csi_P(vc);
2487 		break;
2488 	case 'c':
2489 		if (!vc->vc_par[0])
2490 			respond_ID(tty);
2491 		break;
2492 	case 'g':
2493 		if (!vc->vc_par[0] && vc->state.x < VC_TABSTOPS_COUNT)
2494 			set_bit(vc->state.x, vc->vc_tab_stop);
2495 		else if (vc->vc_par[0] == 3)
2496 			bitmap_zero(vc->vc_tab_stop, VC_TABSTOPS_COUNT);
2497 		break;
2498 	case 'h':
2499 		csi_hl(vc, true);
2500 		break;
2501 	case 'l':
2502 		csi_hl(vc, false);
2503 		break;
2504 	case 'm':
2505 		csi_m(vc);
2506 		break;
2507 	case 'n':
2508 		if (vc->vc_par[0] == 5)
2509 			status_report(tty);
2510 		else if (vc->vc_par[0] == 6)
2511 			cursor_report(vc, tty);
2512 		break;
2513 	case 'q': /* DECLL - but only 3 leds */
2514 		/* map 0,1,2,3 to 0,1,2,4 */
2515 		if (vc->vc_par[0] < 4)
2516 			vt_set_led_state(vc->vc_num,
2517 				    (vc->vc_par[0] < 3) ? vc->vc_par[0] : 4);
2518 		break;
2519 	case 'r':
2520 		if (!vc->vc_par[0])
2521 			vc->vc_par[0]++;
2522 		if (!vc->vc_par[1])
2523 			vc->vc_par[1] = vc->vc_rows;
2524 		/* Minimum allowed region is 2 lines */
2525 		if (vc->vc_par[0] < vc->vc_par[1] &&
2526 		    vc->vc_par[1] <= vc->vc_rows) {
2527 			vc->vc_top = vc->vc_par[0] - 1;
2528 			vc->vc_bottom = vc->vc_par[1];
2529 			gotoxay(vc, 0, 0);
2530 		}
2531 		break;
2532 	case 's':
2533 		save_cur(vc);
2534 		break;
2535 	case 'u':
2536 		restore_cur(vc);
2537 		break;
2538 	case 'X':
2539 		csi_X(vc);
2540 		break;
2541 	case '@':
2542 		csi_at(vc, vc->vc_par[0]);
2543 		break;
2544 	case ']':
2545 		csi_RSB(vc);
2546 		break;
2547 	}
2548 
2549 }
2550 
2551 static void vc_reset_params(struct vc_data *vc)
2552 {
2553 	memset(vc->vc_par, 0, sizeof(vc->vc_par));
2554 	vc->vc_npar = 0;
2555 }
2556 
2557 /* console_lock is held */
2558 static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, u8 c)
2559 {
2560 	/*
2561 	 *  Control characters can be used in the _middle_
2562 	 *  of an escape sequence, aside from ANSI control strings.
2563 	 */
2564 	if (ansi_control_string(vc->vc_state) && c >= ASCII_IGNORE_FIRST &&
2565 	    c <= ASCII_IGNORE_LAST)
2566 		return;
2567 
2568 	if (handle_ascii(tty, vc, c))
2569 		return;
2570 
2571 	switch(vc->vc_state) {
2572 	case ESesc:	/* ESC */
2573 		handle_esc(tty, vc, c);
2574 		return;
2575 	case ESnonstd:	/* ESC ] aka OSC */
2576 		switch (c) {
2577 		case 'P': /* palette escape sequence */
2578 			vc_reset_params(vc);
2579 			vc->vc_state = ESpalette;
2580 			return;
2581 		case 'R': /* reset palette */
2582 			reset_palette(vc);
2583 			break;
2584 		case '0' ... '9':
2585 			vc->vc_state = ESosc;
2586 			return;
2587 		}
2588 		vc->vc_state = ESnormal;
2589 		return;
2590 	case ESpalette:	/* ESC ] P aka OSC P */
2591 		if (isxdigit(c)) {
2592 			vc->vc_par[vc->vc_npar++] = hex_to_bin(c);
2593 			if (vc->vc_npar == 7) {
2594 				int i = vc->vc_par[0] * 3, j = 1;
2595 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2596 				vc->vc_palette[i++] += vc->vc_par[j++];
2597 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2598 				vc->vc_palette[i++] += vc->vc_par[j++];
2599 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2600 				vc->vc_palette[i] += vc->vc_par[j];
2601 				set_palette(vc);
2602 				vc->vc_state = ESnormal;
2603 			}
2604 		} else
2605 			vc->vc_state = ESnormal;
2606 		return;
2607 	case ESsquare:	/* ESC [ aka CSI, parameters or modifiers expected */
2608 		vc_reset_params(vc);
2609 
2610 		vc->vc_state = ESgetpars;
2611 		switch (c) {
2612 		case '[': /* Function key */
2613 			vc->vc_state = ESfunckey;
2614 			return;
2615 		case '?':
2616 			vc->vc_priv = EPdec;
2617 			return;
2618 		case '>':
2619 			vc->vc_priv = EPgt;
2620 			return;
2621 		case '=':
2622 			vc->vc_priv = EPeq;
2623 			return;
2624 		case '<':
2625 			vc->vc_priv = EPlt;
2626 			return;
2627 		}
2628 		vc->vc_priv = EPecma;
2629 		fallthrough;
2630 	case ESgetpars: /* ESC [ aka CSI, parameters expected */
2631 		switch (c) {
2632 		case ';':
2633 			if (vc->vc_npar < NPAR - 1) {
2634 				vc->vc_npar++;
2635 				return;
2636 			}
2637 			break;
2638 		case '0' ... '9':
2639 			vc->vc_par[vc->vc_npar] *= 10;
2640 			vc->vc_par[vc->vc_npar] += c - '0';
2641 			return;
2642 		}
2643 		if (c >= ASCII_CSI_IGNORE_FIRST && c <= ASCII_CSI_IGNORE_LAST) {
2644 			vc->vc_state = EScsiignore;
2645 			return;
2646 		}
2647 
2648 		/* parameters done, handle the control char @c */
2649 
2650 		vc->vc_state = ESnormal;
2651 
2652 		switch (vc->vc_priv) {
2653 		case EPdec:
2654 			csi_DEC(tty, vc, c);
2655 			return;
2656 		case EPecma:
2657 			csi_ECMA(tty, vc, c);
2658 			return;
2659 		default:
2660 			return;
2661 		}
2662 	case EScsiignore:
2663 		if (c >= ASCII_CSI_IGNORE_FIRST && c <= ASCII_CSI_IGNORE_LAST)
2664 			return;
2665 		vc->vc_state = ESnormal;
2666 		return;
2667 	case ESpercent:	/* ESC % */
2668 		vc->vc_state = ESnormal;
2669 		switch (c) {
2670 		case '@':  /* defined in ISO 2022 */
2671 			vc->vc_utf = 0;
2672 			return;
2673 		case 'G':  /* prelim official escape code */
2674 		case '8':  /* retained for compatibility */
2675 			vc->vc_utf = 1;
2676 			return;
2677 		}
2678 		return;
2679 	case ESfunckey:	/* ESC [ [ aka CSI [ */
2680 		vc->vc_state = ESnormal;
2681 		return;
2682 	case EShash:	/* ESC # */
2683 		vc->vc_state = ESnormal;
2684 		if (c == '8') {
2685 			/* DEC screen alignment test. kludge :-) */
2686 			vc->vc_video_erase_char =
2687 				(vc->vc_video_erase_char & 0xff00) | 'E';
2688 			csi_J(vc, CSI_J_VISIBLE);
2689 			vc->vc_video_erase_char =
2690 				(vc->vc_video_erase_char & 0xff00) | ' ';
2691 			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
2692 		}
2693 		return;
2694 	case ESsetG0:	/* ESC ( */
2695 		vc_setGx(vc, 0, c);
2696 		vc->vc_state = ESnormal;
2697 		return;
2698 	case ESsetG1:	/* ESC ) */
2699 		vc_setGx(vc, 1, c);
2700 		vc->vc_state = ESnormal;
2701 		return;
2702 	case ESapc:	/* ESC _ */
2703 		return;
2704 	case ESosc:	/* ESC ] [0-9] aka OSC [0-9] */
2705 		return;
2706 	case ESpm:	/* ESC ^ */
2707 		return;
2708 	case ESdcs:	/* ESC P */
2709 		return;
2710 	default:
2711 		vc->vc_state = ESnormal;
2712 	}
2713 }
2714 
2715 /* is_double_width() is based on the wcwidth() implementation by
2716  * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
2717  * Latest version: https://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
2718  */
2719 struct interval {
2720 	uint32_t first;
2721 	uint32_t last;
2722 };
2723 
2724 static int ucs_cmp(const void *key, const void *elt)
2725 {
2726 	uint32_t ucs = *(uint32_t *)key;
2727 	struct interval e = *(struct interval *) elt;
2728 
2729 	if (ucs > e.last)
2730 		return 1;
2731 	else if (ucs < e.first)
2732 		return -1;
2733 	return 0;
2734 }
2735 
2736 static int is_double_width(uint32_t ucs)
2737 {
2738 	static const struct interval double_width[] = {
2739 		{ 0x1100, 0x115F }, { 0x2329, 0x232A }, { 0x2E80, 0x303E },
2740 		{ 0x3040, 0xA4CF }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF },
2741 		{ 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 },
2742 		{ 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }
2743 	};
2744 	if (ucs < double_width[0].first ||
2745 	    ucs > double_width[ARRAY_SIZE(double_width) - 1].last)
2746 		return 0;
2747 
2748 	return bsearch(&ucs, double_width, ARRAY_SIZE(double_width),
2749 			sizeof(struct interval), ucs_cmp) != NULL;
2750 }
2751 
2752 struct vc_draw_region {
2753 	unsigned long from, to;
2754 	int x;
2755 };
2756 
2757 static void con_flush(struct vc_data *vc, struct vc_draw_region *draw)
2758 {
2759 	if (draw->x < 0)
2760 		return;
2761 
2762 	vc->vc_sw->con_putcs(vc, (u16 *)draw->from,
2763 			(u16 *)draw->to - (u16 *)draw->from, vc->state.y,
2764 			draw->x);
2765 	draw->x = -1;
2766 }
2767 
2768 static inline int vc_translate_ascii(const struct vc_data *vc, int c)
2769 {
2770 	if (IS_ENABLED(CONFIG_CONSOLE_TRANSLATIONS)) {
2771 		if (vc->vc_toggle_meta)
2772 			c |= 0x80;
2773 
2774 		return vc->vc_translate[c];
2775 	}
2776 
2777 	return c;
2778 }
2779 
2780 
2781 /**
2782  * vc_sanitize_unicode - Replace invalid Unicode code points with ``U+FFFD``
2783  * @c: the received code point
2784  */
2785 static inline int vc_sanitize_unicode(const int c)
2786 {
2787 	if (c >= 0xd800 && c <= 0xdfff)
2788 		return 0xfffd;
2789 
2790 	return c;
2791 }
2792 
2793 /**
2794  * vc_translate_unicode - Combine UTF-8 into Unicode in &vc_data.vc_utf_char
2795  * @vc: virtual console
2796  * @c: UTF-8 byte to translate
2797  * @rescan: set to true iff @c wasn't consumed here and needs to be re-processed
2798  *
2799  * * &vc_data.vc_utf_char is the being-constructed Unicode code point.
2800  * * &vc_data.vc_utf_count is the number of continuation bytes still expected to
2801  *   arrive.
2802  * * &vc_data.vc_npar is the number of continuation bytes arrived so far.
2803  *
2804  * Return:
2805  * * %-1 - Input OK so far, @c consumed, further bytes expected.
2806  * * %0xFFFD - Possibility 1: input invalid, @c may have been consumed (see
2807  *             desc. of @rescan). Possibility 2: input OK, @c consumed,
2808  *             ``U+FFFD`` is the resulting code point. ``U+FFFD`` is valid,
2809  *             ``REPLACEMENT CHARACTER``.
2810  * * otherwise - Input OK, @c consumed, resulting code point returned.
2811  */
2812 static int vc_translate_unicode(struct vc_data *vc, int c, bool *rescan)
2813 {
2814 	static const u32 utf8_length_changes[] = {0x7f, 0x7ff, 0xffff, 0x10ffff};
2815 
2816 	/* Continuation byte received */
2817 	if ((c & 0xc0) == 0x80) {
2818 		/* Unexpected continuation byte? */
2819 		if (!vc->vc_utf_count)
2820 			return 0xfffd;
2821 
2822 		vc->vc_utf_char = (vc->vc_utf_char << 6) | (c & 0x3f);
2823 		vc->vc_npar++;
2824 		if (--vc->vc_utf_count)
2825 			goto need_more_bytes;
2826 
2827 		/* Got a whole character */
2828 		c = vc->vc_utf_char;
2829 		/* Reject overlong sequences */
2830 		if (c <= utf8_length_changes[vc->vc_npar - 1] ||
2831 				c > utf8_length_changes[vc->vc_npar])
2832 			return 0xfffd;
2833 
2834 		return vc_sanitize_unicode(c);
2835 	}
2836 
2837 	/* Single ASCII byte or first byte of a sequence received */
2838 	if (vc->vc_utf_count) {
2839 		/* Continuation byte expected */
2840 		*rescan = true;
2841 		vc->vc_utf_count = 0;
2842 		return 0xfffd;
2843 	}
2844 
2845 	/* Nothing to do if an ASCII byte was received */
2846 	if (c <= 0x7f)
2847 		return c;
2848 
2849 	/* First byte of a multibyte sequence received */
2850 	vc->vc_npar = 0;
2851 	if ((c & 0xe0) == 0xc0) {
2852 		vc->vc_utf_count = 1;
2853 		vc->vc_utf_char = (c & 0x1f);
2854 	} else if ((c & 0xf0) == 0xe0) {
2855 		vc->vc_utf_count = 2;
2856 		vc->vc_utf_char = (c & 0x0f);
2857 	} else if ((c & 0xf8) == 0xf0) {
2858 		vc->vc_utf_count = 3;
2859 		vc->vc_utf_char = (c & 0x07);
2860 	} else {
2861 		return 0xfffd;
2862 	}
2863 
2864 need_more_bytes:
2865 	return -1;
2866 }
2867 
2868 static int vc_translate(struct vc_data *vc, int *c, bool *rescan)
2869 {
2870 	/* Do no translation at all in control states */
2871 	if (vc->vc_state != ESnormal)
2872 		return *c;
2873 
2874 	if (vc->vc_utf && !vc->vc_disp_ctrl)
2875 		return *c = vc_translate_unicode(vc, *c, rescan);
2876 
2877 	/* no utf or alternate charset mode */
2878 	return vc_translate_ascii(vc, *c);
2879 }
2880 
2881 static inline unsigned char vc_invert_attr(const struct vc_data *vc)
2882 {
2883 	if (!vc->vc_can_do_color)
2884 		return vc->vc_attr ^ 0x08;
2885 
2886 	if (vc->vc_hi_font_mask == 0x100)
2887 		return   (vc->vc_attr & 0x11) |
2888 			((vc->vc_attr & 0xe0) >> 4) |
2889 			((vc->vc_attr & 0x0e) << 4);
2890 
2891 	return   (vc->vc_attr & 0x88) |
2892 		((vc->vc_attr & 0x70) >> 4) |
2893 		((vc->vc_attr & 0x07) << 4);
2894 }
2895 
2896 static bool vc_is_control(struct vc_data *vc, int tc, int c)
2897 {
2898 	/*
2899 	 * A bitmap for codes <32. A bit of 1 indicates that the code
2900 	 * corresponding to that bit number invokes some special action (such
2901 	 * as cursor movement) and should not be displayed as a glyph unless
2902 	 * the disp_ctrl mode is explicitly enabled.
2903 	 */
2904 	static const u32 CTRL_ACTION = BIT(ASCII_NULL) |
2905 		GENMASK(ASCII_SHIFTIN, ASCII_BELL) | BIT(ASCII_CANCEL) |
2906 		BIT(ASCII_SUBSTITUTE) | BIT(ASCII_ESCAPE);
2907 	/* Cannot be overridden by disp_ctrl */
2908 	static const u32 CTRL_ALWAYS = BIT(ASCII_NULL) | BIT(ASCII_BACKSPACE) |
2909 		BIT(ASCII_LINEFEED) | BIT(ASCII_SHIFTIN) | BIT(ASCII_SHIFTOUT) |
2910 		BIT(ASCII_CAR_RET) | BIT(ASCII_FORMFEED) | BIT(ASCII_ESCAPE);
2911 
2912 	if (vc->vc_state != ESnormal)
2913 		return true;
2914 
2915 	if (!tc)
2916 		return true;
2917 
2918 	/*
2919 	 * If the original code was a control character we only allow a glyph
2920 	 * to be displayed if the code is not normally used (such as for cursor
2921 	 * movement) or if the disp_ctrl mode has been explicitly enabled.
2922 	 * Certain characters (as given by the CTRL_ALWAYS bitmap) are always
2923 	 * displayed as control characters, as the console would be pretty
2924 	 * useless without them; to display an arbitrary font position use the
2925 	 * direct-to-font zone in UTF-8 mode.
2926 	 */
2927 	if (c < BITS_PER_TYPE(CTRL_ALWAYS)) {
2928 		if (vc->vc_disp_ctrl)
2929 			return CTRL_ALWAYS & BIT(c);
2930 		else
2931 			return vc->vc_utf || (CTRL_ACTION & BIT(c));
2932 	}
2933 
2934 	if (c == ASCII_DEL && !vc->vc_disp_ctrl)
2935 		return true;
2936 
2937 	if (c == ASCII_EXT_CSI)
2938 		return true;
2939 
2940 	return false;
2941 }
2942 
2943 static int vc_con_write_normal(struct vc_data *vc, int tc, int c,
2944 		struct vc_draw_region *draw)
2945 {
2946 	int next_c;
2947 	unsigned char vc_attr = vc->vc_attr;
2948 	u16 himask = vc->vc_hi_font_mask, charmask = himask ? 0x1ff : 0xff;
2949 	u8 width = 1;
2950 	bool inverse = false;
2951 
2952 	if (vc->vc_utf && !vc->vc_disp_ctrl) {
2953 		if (is_double_width(c))
2954 			width = 2;
2955 	}
2956 
2957 	/* Now try to find out how to display it */
2958 	tc = conv_uni_to_pc(vc, tc);
2959 	if (tc & ~charmask) {
2960 		if (tc == -1 || tc == -2)
2961 			return -1; /* nothing to display */
2962 
2963 		/* Glyph not found */
2964 		if ((!vc->vc_utf || vc->vc_disp_ctrl || c < 128) &&
2965 				!(c & ~charmask)) {
2966 			/*
2967 			 * In legacy mode use the glyph we get by a 1:1
2968 			 * mapping.
2969 			 * This would make absolutely no sense with Unicode in
2970 			 * mind, but do this for ASCII characters since a font
2971 			 * may lack Unicode mapping info and we don't want to
2972 			 * end up with having question marks only.
2973 			 */
2974 			tc = c;
2975 		} else {
2976 			/*
2977 			 * Display U+FFFD. If it's not found, display an inverse
2978 			 * question mark.
2979 			 */
2980 			tc = conv_uni_to_pc(vc, 0xfffd);
2981 			if (tc < 0) {
2982 				inverse = true;
2983 				tc = conv_uni_to_pc(vc, '?');
2984 				if (tc < 0)
2985 					tc = '?';
2986 
2987 				vc_attr = vc_invert_attr(vc);
2988 				con_flush(vc, draw);
2989 			}
2990 		}
2991 	}
2992 
2993 	next_c = c;
2994 	while (1) {
2995 		if (vc->vc_need_wrap || vc->vc_decim)
2996 			con_flush(vc, draw);
2997 		if (vc->vc_need_wrap) {
2998 			cr(vc);
2999 			lf(vc);
3000 		}
3001 		if (vc->vc_decim)
3002 			insert_char(vc, 1);
3003 		vc_uniscr_putc(vc, next_c);
3004 
3005 		if (himask)
3006 			tc = ((tc & 0x100) ? himask : 0) |
3007 			      (tc &  0xff);
3008 		tc |= (vc_attr << 8) & ~himask;
3009 
3010 		scr_writew(tc, (u16 *)vc->vc_pos);
3011 
3012 		if (con_should_update(vc) && draw->x < 0) {
3013 			draw->x = vc->state.x;
3014 			draw->from = vc->vc_pos;
3015 		}
3016 		if (vc->state.x == vc->vc_cols - 1) {
3017 			vc->vc_need_wrap = vc->vc_decawm;
3018 			draw->to = vc->vc_pos + 2;
3019 		} else {
3020 			vc->state.x++;
3021 			draw->to = (vc->vc_pos += 2);
3022 		}
3023 
3024 		if (!--width)
3025 			break;
3026 
3027 		/* A space is printed in the second column */
3028 		tc = conv_uni_to_pc(vc, ' ');
3029 		if (tc < 0)
3030 			tc = ' ';
3031 		next_c = ' ';
3032 	}
3033 	notify_write(vc, c);
3034 
3035 	if (inverse)
3036 		con_flush(vc, draw);
3037 
3038 	return 0;
3039 }
3040 
3041 /* acquires console_lock */
3042 static int do_con_write(struct tty_struct *tty, const u8 *buf, int count)
3043 {
3044 	struct vc_draw_region draw = {
3045 		.x = -1,
3046 	};
3047 	int c, tc, n = 0;
3048 	unsigned int currcons;
3049 	struct vc_data *vc = tty->driver_data;
3050 	struct vt_notifier_param param;
3051 	bool rescan;
3052 
3053 	if (in_interrupt())
3054 		return count;
3055 
3056 	console_lock();
3057 	currcons = vc->vc_num;
3058 	if (!vc_cons_allocated(currcons)) {
3059 		/* could this happen? */
3060 		pr_warn_once("con_write: tty %d not allocated\n", currcons+1);
3061 		console_unlock();
3062 		return 0;
3063 	}
3064 
3065 
3066 	/* undraw cursor first */
3067 	if (con_is_fg(vc))
3068 		hide_cursor(vc);
3069 
3070 	param.vc = vc;
3071 
3072 	while (!tty->flow.stopped && count) {
3073 		u8 orig = *buf;
3074 		buf++;
3075 		n++;
3076 		count--;
3077 rescan_last_byte:
3078 		c = orig;
3079 		rescan = false;
3080 
3081 		tc = vc_translate(vc, &c, &rescan);
3082 		if (tc == -1)
3083 			continue;
3084 
3085 		param.c = tc;
3086 		if (atomic_notifier_call_chain(&vt_notifier_list, VT_PREWRITE,
3087 					&param) == NOTIFY_STOP)
3088 			continue;
3089 
3090 		if (vc_is_control(vc, tc, c)) {
3091 			con_flush(vc, &draw);
3092 			do_con_trol(tty, vc, orig);
3093 			continue;
3094 		}
3095 
3096 		if (vc_con_write_normal(vc, tc, c, &draw) < 0)
3097 			continue;
3098 
3099 		if (rescan)
3100 			goto rescan_last_byte;
3101 	}
3102 	con_flush(vc, &draw);
3103 	console_conditional_schedule();
3104 	notify_update(vc);
3105 	console_unlock();
3106 	return n;
3107 }
3108 
3109 /*
3110  * This is the console switching callback.
3111  *
3112  * Doing console switching in a process context allows
3113  * us to do the switches asynchronously (needed when we want
3114  * to switch due to a keyboard interrupt).  Synchronization
3115  * with other console code and prevention of re-entrancy is
3116  * ensured with console_lock.
3117  */
3118 static void console_callback(struct work_struct *ignored)
3119 {
3120 	console_lock();
3121 
3122 	if (want_console >= 0) {
3123 		if (want_console != fg_console &&
3124 		    vc_cons_allocated(want_console)) {
3125 			hide_cursor(vc_cons[fg_console].d);
3126 			change_console(vc_cons[want_console].d);
3127 			/* we only changed when the console had already
3128 			   been allocated - a new console is not created
3129 			   in an interrupt routine */
3130 		}
3131 		want_console = -1;
3132 	}
3133 	if (do_poke_blanked_console) { /* do not unblank for a LED change */
3134 		do_poke_blanked_console = 0;
3135 		poke_blanked_console();
3136 	}
3137 	if (scrollback_delta) {
3138 		struct vc_data *vc = vc_cons[fg_console].d;
3139 		clear_selection();
3140 		if (vc->vc_mode == KD_TEXT && vc->vc_sw->con_scrolldelta)
3141 			vc->vc_sw->con_scrolldelta(vc, scrollback_delta);
3142 		scrollback_delta = 0;
3143 	}
3144 	if (blank_timer_expired) {
3145 		do_blank_screen(0);
3146 		blank_timer_expired = 0;
3147 	}
3148 	notify_update(vc_cons[fg_console].d);
3149 
3150 	console_unlock();
3151 }
3152 
3153 int set_console(int nr)
3154 {
3155 	struct vc_data *vc = vc_cons[fg_console].d;
3156 
3157 	if (!vc_cons_allocated(nr) || vt_dont_switch ||
3158 		(vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) {
3159 
3160 		/*
3161 		 * Console switch will fail in console_callback() or
3162 		 * change_console() so there is no point scheduling
3163 		 * the callback
3164 		 *
3165 		 * Existing set_console() users don't check the return
3166 		 * value so this shouldn't break anything
3167 		 */
3168 		return -EINVAL;
3169 	}
3170 
3171 	want_console = nr;
3172 	schedule_console_callback();
3173 
3174 	return 0;
3175 }
3176 
3177 struct tty_driver *console_driver;
3178 
3179 #ifdef CONFIG_VT_CONSOLE
3180 
3181 /**
3182  * vt_kmsg_redirect() - sets/gets the kernel message console
3183  * @new: the new virtual terminal number or -1 if the console should stay
3184  *	unchanged
3185  *
3186  * By default, the kernel messages are always printed on the current virtual
3187  * console. However, the user may modify that default with the
3188  * %TIOCL_SETKMSGREDIRECT ioctl call.
3189  *
3190  * This function sets the kernel message console to be @new. It returns the old
3191  * virtual console number. The virtual terminal number %0 (both as parameter and
3192  * return value) means no redirection (i.e. always printed on the currently
3193  * active console).
3194  *
3195  * The parameter -1 means that only the current console is returned, but the
3196  * value is not modified. You may use the macro vt_get_kmsg_redirect() in that
3197  * case to make the code more understandable.
3198  *
3199  * When the kernel is compiled without %CONFIG_VT_CONSOLE, this function ignores
3200  * the parameter and always returns %0.
3201  */
3202 int vt_kmsg_redirect(int new)
3203 {
3204 	static int kmsg_con;
3205 
3206 	if (new != -1)
3207 		return xchg(&kmsg_con, new);
3208 	else
3209 		return kmsg_con;
3210 }
3211 
3212 /*
3213  *	Console on virtual terminal
3214  *
3215  * The console must be locked when we get here.
3216  */
3217 
3218 static void vt_console_print(struct console *co, const char *b, unsigned count)
3219 {
3220 	struct vc_data *vc = vc_cons[fg_console].d;
3221 	unsigned char c;
3222 	static DEFINE_SPINLOCK(printing_lock);
3223 	const ushort *start;
3224 	ushort start_x, cnt;
3225 	int kmsg_console;
3226 
3227 	WARN_CONSOLE_UNLOCKED();
3228 
3229 	/* this protects against concurrent oops only */
3230 	if (!spin_trylock(&printing_lock))
3231 		return;
3232 
3233 	kmsg_console = vt_get_kmsg_redirect();
3234 	if (kmsg_console && vc_cons_allocated(kmsg_console - 1))
3235 		vc = vc_cons[kmsg_console - 1].d;
3236 
3237 	if (!vc_cons_allocated(fg_console)) {
3238 		/* impossible */
3239 		/* printk("vt_console_print: tty %d not allocated ??\n", currcons+1); */
3240 		goto quit;
3241 	}
3242 
3243 	if (vc->vc_mode != KD_TEXT)
3244 		goto quit;
3245 
3246 	/* undraw cursor first */
3247 	if (con_is_fg(vc))
3248 		hide_cursor(vc);
3249 
3250 	start = (ushort *)vc->vc_pos;
3251 	start_x = vc->state.x;
3252 	cnt = 0;
3253 	while (count--) {
3254 		c = *b++;
3255 		if (c == ASCII_LINEFEED || c == ASCII_CAR_RET ||
3256 		    c == ASCII_BACKSPACE || vc->vc_need_wrap) {
3257 			if (cnt && con_is_visible(vc))
3258 				vc->vc_sw->con_putcs(vc, start, cnt, vc->state.y, start_x);
3259 			cnt = 0;
3260 			if (c == ASCII_BACKSPACE) {
3261 				bs(vc);
3262 				start = (ushort *)vc->vc_pos;
3263 				start_x = vc->state.x;
3264 				continue;
3265 			}
3266 			if (c != ASCII_CAR_RET)
3267 				lf(vc);
3268 			cr(vc);
3269 			start = (ushort *)vc->vc_pos;
3270 			start_x = vc->state.x;
3271 			if (c == ASCII_LINEFEED || c == ASCII_CAR_RET)
3272 				continue;
3273 		}
3274 		vc_uniscr_putc(vc, c);
3275 		scr_writew((vc->vc_attr << 8) + c, (unsigned short *)vc->vc_pos);
3276 		notify_write(vc, c);
3277 		cnt++;
3278 		if (vc->state.x == vc->vc_cols - 1) {
3279 			vc->vc_need_wrap = 1;
3280 		} else {
3281 			vc->vc_pos += 2;
3282 			vc->state.x++;
3283 		}
3284 	}
3285 	if (cnt && con_is_visible(vc))
3286 		vc->vc_sw->con_putcs(vc, start, cnt, vc->state.y, start_x);
3287 	set_cursor(vc);
3288 	notify_update(vc);
3289 
3290 quit:
3291 	spin_unlock(&printing_lock);
3292 }
3293 
3294 static struct tty_driver *vt_console_device(struct console *c, int *index)
3295 {
3296 	*index = c->index ? c->index-1 : fg_console;
3297 	return console_driver;
3298 }
3299 
3300 static int vt_console_setup(struct console *co, char *options)
3301 {
3302 	return co->index >= MAX_NR_CONSOLES ? -EINVAL : 0;
3303 }
3304 
3305 static struct console vt_console_driver = {
3306 	.name		= "tty",
3307 	.setup		= vt_console_setup,
3308 	.write		= vt_console_print,
3309 	.device		= vt_console_device,
3310 	.unblank	= unblank_screen,
3311 	.flags		= CON_PRINTBUFFER,
3312 	.index		= -1,
3313 };
3314 #endif
3315 
3316 /*
3317  *	Handling of Linux-specific VC ioctls
3318  */
3319 
3320 /*
3321  * Generally a bit racy with respect to console_lock();.
3322  *
3323  * There are some functions which don't need it.
3324  *
3325  * There are some functions which can sleep for arbitrary periods
3326  * (paste_selection) but we don't need the lock there anyway.
3327  *
3328  * set_selection_user has locking, and definitely needs it
3329  */
3330 
3331 int tioclinux(struct tty_struct *tty, unsigned long arg)
3332 {
3333 	char type, data;
3334 	char __user *p = (char __user *)arg;
3335 	void __user *param_aligned32 = (u32 __user *)arg + 1;
3336 	void __user *param = (void __user *)arg + 1;
3337 	int lines;
3338 	int ret;
3339 
3340 	if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
3341 		return -EPERM;
3342 	if (get_user(type, p))
3343 		return -EFAULT;
3344 	ret = 0;
3345 
3346 	switch (type) {
3347 	case TIOCL_SETSEL:
3348 		return set_selection_user(param, tty);
3349 	case TIOCL_PASTESEL:
3350 		if (!capable(CAP_SYS_ADMIN))
3351 			return -EPERM;
3352 		return paste_selection(tty);
3353 	case TIOCL_UNBLANKSCREEN:
3354 		console_lock();
3355 		unblank_screen();
3356 		console_unlock();
3357 		break;
3358 	case TIOCL_SELLOADLUT:
3359 		if (!capable(CAP_SYS_ADMIN))
3360 			return -EPERM;
3361 		return sel_loadlut(param_aligned32);
3362 	case TIOCL_GETSHIFTSTATE:
3363 		/*
3364 		 * Make it possible to react to Shift+Mousebutton. Note that
3365 		 * 'shift_state' is an undocumented kernel-internal variable;
3366 		 * programs not closely related to the kernel should not use
3367 		 * this.
3368 		 */
3369 		data = vt_get_shift_state();
3370 		return put_user(data, p);
3371 	case TIOCL_GETMOUSEREPORTING:
3372 		console_lock();	/* May be overkill */
3373 		data = mouse_reporting();
3374 		console_unlock();
3375 		return put_user(data, p);
3376 	case TIOCL_SETVESABLANK:
3377 		return set_vesa_blanking(param);
3378 	case TIOCL_GETKMSGREDIRECT:
3379 		data = vt_get_kmsg_redirect();
3380 		return put_user(data, p);
3381 	case TIOCL_SETKMSGREDIRECT:
3382 		if (!capable(CAP_SYS_ADMIN))
3383 			return -EPERM;
3384 
3385 		if (get_user(data, p+1))
3386 			return -EFAULT;
3387 
3388 		vt_kmsg_redirect(data);
3389 
3390 		break;
3391 	case TIOCL_GETFGCONSOLE:
3392 		/*
3393 		 * No locking needed as this is a transiently correct return
3394 		 * anyway if the caller hasn't disabled switching.
3395 		 */
3396 		return fg_console;
3397 	case TIOCL_SCROLLCONSOLE:
3398 		if (get_user(lines, (s32 __user *)param_aligned32))
3399 			return -EFAULT;
3400 
3401 		/*
3402 		 * Needs the console lock here. Note that lots of other calls
3403 		 * need fixing before the lock is actually useful!
3404 		 */
3405 		console_lock();
3406 		scrollfront(vc_cons[fg_console].d, lines);
3407 		console_unlock();
3408 		break;
3409 	case TIOCL_BLANKSCREEN:	/* until explicitly unblanked, not only poked */
3410 		console_lock();
3411 		ignore_poke = 1;
3412 		do_blank_screen(0);
3413 		console_unlock();
3414 		break;
3415 	case TIOCL_BLANKEDSCREEN:
3416 		return console_blanked;
3417 	default:
3418 		return -EINVAL;
3419 	}
3420 
3421 	return ret;
3422 }
3423 
3424 /*
3425  * /dev/ttyN handling
3426  */
3427 
3428 static ssize_t con_write(struct tty_struct *tty, const u8 *buf, size_t count)
3429 {
3430 	int	retval;
3431 
3432 	retval = do_con_write(tty, buf, count);
3433 	con_flush_chars(tty);
3434 
3435 	return retval;
3436 }
3437 
3438 static int con_put_char(struct tty_struct *tty, u8 ch)
3439 {
3440 	return do_con_write(tty, &ch, 1);
3441 }
3442 
3443 static unsigned int con_write_room(struct tty_struct *tty)
3444 {
3445 	if (tty->flow.stopped)
3446 		return 0;
3447 	return 32768;		/* No limit, really; we're not buffering */
3448 }
3449 
3450 /*
3451  * con_throttle and con_unthrottle are only used for
3452  * paste_selection(), which has to stuff in a large number of
3453  * characters...
3454  */
3455 static void con_throttle(struct tty_struct *tty)
3456 {
3457 }
3458 
3459 static void con_unthrottle(struct tty_struct *tty)
3460 {
3461 	struct vc_data *vc = tty->driver_data;
3462 
3463 	wake_up_interruptible(&vc->paste_wait);
3464 }
3465 
3466 /*
3467  * Turn the Scroll-Lock LED on when the tty is stopped
3468  */
3469 static void con_stop(struct tty_struct *tty)
3470 {
3471 	int console_num;
3472 	if (!tty)
3473 		return;
3474 	console_num = tty->index;
3475 	if (!vc_cons_allocated(console_num))
3476 		return;
3477 	vt_kbd_con_stop(console_num);
3478 }
3479 
3480 /*
3481  * Turn the Scroll-Lock LED off when the console is started
3482  */
3483 static void con_start(struct tty_struct *tty)
3484 {
3485 	int console_num;
3486 	if (!tty)
3487 		return;
3488 	console_num = tty->index;
3489 	if (!vc_cons_allocated(console_num))
3490 		return;
3491 	vt_kbd_con_start(console_num);
3492 }
3493 
3494 static void con_flush_chars(struct tty_struct *tty)
3495 {
3496 	struct vc_data *vc = tty->driver_data;
3497 
3498 	if (in_interrupt())	/* from flush_to_ldisc */
3499 		return;
3500 
3501 	console_lock();
3502 	set_cursor(vc);
3503 	console_unlock();
3504 }
3505 
3506 /*
3507  * Allocate the console screen memory.
3508  */
3509 static int con_install(struct tty_driver *driver, struct tty_struct *tty)
3510 {
3511 	unsigned int currcons = tty->index;
3512 	struct vc_data *vc;
3513 	int ret;
3514 
3515 	console_lock();
3516 	ret = vc_allocate(currcons);
3517 	if (ret)
3518 		goto unlock;
3519 
3520 	vc = vc_cons[currcons].d;
3521 
3522 	/* Still being freed */
3523 	if (vc->port.tty) {
3524 		ret = -ERESTARTSYS;
3525 		goto unlock;
3526 	}
3527 
3528 	ret = tty_port_install(&vc->port, driver, tty);
3529 	if (ret)
3530 		goto unlock;
3531 
3532 	tty->driver_data = vc;
3533 	vc->port.tty = tty;
3534 	tty_port_get(&vc->port);
3535 
3536 	if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
3537 		tty->winsize.ws_row = vc_cons[currcons].d->vc_rows;
3538 		tty->winsize.ws_col = vc_cons[currcons].d->vc_cols;
3539 	}
3540 	if (vc->vc_utf)
3541 		tty->termios.c_iflag |= IUTF8;
3542 	else
3543 		tty->termios.c_iflag &= ~IUTF8;
3544 unlock:
3545 	console_unlock();
3546 	return ret;
3547 }
3548 
3549 static int con_open(struct tty_struct *tty, struct file *filp)
3550 {
3551 	/* everything done in install */
3552 	return 0;
3553 }
3554 
3555 
3556 static void con_close(struct tty_struct *tty, struct file *filp)
3557 {
3558 	/* Nothing to do - we defer to shutdown */
3559 }
3560 
3561 static void con_shutdown(struct tty_struct *tty)
3562 {
3563 	struct vc_data *vc = tty->driver_data;
3564 	BUG_ON(vc == NULL);
3565 	console_lock();
3566 	vc->port.tty = NULL;
3567 	console_unlock();
3568 }
3569 
3570 static void con_cleanup(struct tty_struct *tty)
3571 {
3572 	struct vc_data *vc = tty->driver_data;
3573 
3574 	tty_port_put(&vc->port);
3575 }
3576 
3577 /*
3578  * We can't deal with anything but the N_TTY ldisc,
3579  * because we can sleep in our write() routine.
3580  */
3581 static int con_ldisc_ok(struct tty_struct *tty, int ldisc)
3582 {
3583 	return ldisc == N_TTY ? 0 : -EINVAL;
3584 }
3585 
3586 static int default_color           = 7; /* white */
3587 static int default_italic_color    = 2; // green (ASCII)
3588 static int default_underline_color = 3; // cyan (ASCII)
3589 module_param_named(color, default_color, int, S_IRUGO | S_IWUSR);
3590 module_param_named(italic, default_italic_color, int, S_IRUGO | S_IWUSR);
3591 module_param_named(underline, default_underline_color, int, S_IRUGO | S_IWUSR);
3592 
3593 static void vc_init(struct vc_data *vc, int do_clear)
3594 {
3595 	int j, k ;
3596 
3597 	set_origin(vc);
3598 	vc->vc_pos = vc->vc_origin;
3599 	reset_vc(vc);
3600 	for (j=k=0; j<16; j++) {
3601 		vc->vc_palette[k++] = default_red[j] ;
3602 		vc->vc_palette[k++] = default_grn[j] ;
3603 		vc->vc_palette[k++] = default_blu[j] ;
3604 	}
3605 	vc->vc_def_color       = default_color;
3606 	vc->vc_ulcolor         = default_underline_color;
3607 	vc->vc_itcolor         = default_italic_color;
3608 	vc->vc_halfcolor       = 0x08;   /* grey */
3609 	init_waitqueue_head(&vc->paste_wait);
3610 	reset_terminal(vc, do_clear);
3611 }
3612 
3613 /*
3614  * This routine initializes console interrupts, and does nothing
3615  * else. If you want the screen to clear, call tty_write with
3616  * the appropriate escape-sequence.
3617  */
3618 
3619 static int __init con_init(void)
3620 {
3621 	const char *display_desc = NULL;
3622 	struct vc_data *vc;
3623 	unsigned int currcons = 0, i;
3624 
3625 	console_lock();
3626 
3627 	if (!conswitchp)
3628 		conswitchp = &dummy_con;
3629 	display_desc = conswitchp->con_startup();
3630 	if (!display_desc) {
3631 		fg_console = 0;
3632 		console_unlock();
3633 		return 0;
3634 	}
3635 
3636 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3637 		struct con_driver *con_driver = &registered_con_driver[i];
3638 
3639 		if (con_driver->con == NULL) {
3640 			con_driver->con = conswitchp;
3641 			con_driver->desc = display_desc;
3642 			con_driver->flag = CON_DRIVER_FLAG_INIT;
3643 			con_driver->first = 0;
3644 			con_driver->last = MAX_NR_CONSOLES - 1;
3645 			break;
3646 		}
3647 	}
3648 
3649 	for (i = 0; i < MAX_NR_CONSOLES; i++)
3650 		con_driver_map[i] = conswitchp;
3651 
3652 	if (blankinterval) {
3653 		blank_state = blank_normal_wait;
3654 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3655 	}
3656 
3657 	for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) {
3658 		vc_cons[currcons].d = vc = kzalloc(sizeof(struct vc_data), GFP_NOWAIT);
3659 		INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
3660 		tty_port_init(&vc->port);
3661 		visual_init(vc, currcons, true);
3662 		/* Assuming vc->vc_{cols,rows,screenbuf_size} are sane here. */
3663 		vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_NOWAIT);
3664 		vc_init(vc, currcons || !vc->vc_sw->con_save_screen);
3665 	}
3666 	currcons = fg_console = 0;
3667 	master_display_fg = vc = vc_cons[currcons].d;
3668 	set_origin(vc);
3669 	save_screen(vc);
3670 	gotoxy(vc, vc->state.x, vc->state.y);
3671 	csi_J(vc, CSI_J_CURSOR_TO_END);
3672 	update_screen(vc);
3673 	pr_info("Console: %s %s %dx%d\n",
3674 		vc->vc_can_do_color ? "colour" : "mono",
3675 		display_desc, vc->vc_cols, vc->vc_rows);
3676 
3677 	console_unlock();
3678 
3679 #ifdef CONFIG_VT_CONSOLE
3680 	register_console(&vt_console_driver);
3681 #endif
3682 	return 0;
3683 }
3684 console_initcall(con_init);
3685 
3686 static const struct tty_operations con_ops = {
3687 	.install = con_install,
3688 	.open = con_open,
3689 	.close = con_close,
3690 	.write = con_write,
3691 	.write_room = con_write_room,
3692 	.put_char = con_put_char,
3693 	.flush_chars = con_flush_chars,
3694 	.ioctl = vt_ioctl,
3695 #ifdef CONFIG_COMPAT
3696 	.compat_ioctl = vt_compat_ioctl,
3697 #endif
3698 	.stop = con_stop,
3699 	.start = con_start,
3700 	.throttle = con_throttle,
3701 	.unthrottle = con_unthrottle,
3702 	.resize = vt_resize,
3703 	.shutdown = con_shutdown,
3704 	.cleanup = con_cleanup,
3705 	.ldisc_ok = con_ldisc_ok,
3706 };
3707 
3708 static struct cdev vc0_cdev;
3709 
3710 static ssize_t show_tty_active(struct device *dev,
3711 				struct device_attribute *attr, char *buf)
3712 {
3713 	return sprintf(buf, "tty%d\n", fg_console + 1);
3714 }
3715 static DEVICE_ATTR(active, S_IRUGO, show_tty_active, NULL);
3716 
3717 static struct attribute *vt_dev_attrs[] = {
3718 	&dev_attr_active.attr,
3719 	NULL
3720 };
3721 
3722 ATTRIBUTE_GROUPS(vt_dev);
3723 
3724 int __init vty_init(const struct file_operations *console_fops)
3725 {
3726 	cdev_init(&vc0_cdev, console_fops);
3727 	if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
3728 	    register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
3729 		panic("Couldn't register /dev/tty0 driver\n");
3730 	tty0dev = device_create_with_groups(&tty_class, NULL,
3731 					    MKDEV(TTY_MAJOR, 0), NULL,
3732 					    vt_dev_groups, "tty0");
3733 	if (IS_ERR(tty0dev))
3734 		tty0dev = NULL;
3735 
3736 	vcs_init();
3737 
3738 	console_driver = tty_alloc_driver(MAX_NR_CONSOLES, TTY_DRIVER_REAL_RAW |
3739 			TTY_DRIVER_RESET_TERMIOS);
3740 	if (IS_ERR(console_driver))
3741 		panic("Couldn't allocate console driver\n");
3742 
3743 	console_driver->name = "tty";
3744 	console_driver->name_base = 1;
3745 	console_driver->major = TTY_MAJOR;
3746 	console_driver->minor_start = 1;
3747 	console_driver->type = TTY_DRIVER_TYPE_CONSOLE;
3748 	console_driver->init_termios = tty_std_termios;
3749 	if (default_utf8)
3750 		console_driver->init_termios.c_iflag |= IUTF8;
3751 	tty_set_operations(console_driver, &con_ops);
3752 	if (tty_register_driver(console_driver))
3753 		panic("Couldn't register console driver\n");
3754 	kbd_init();
3755 	console_map_init();
3756 #ifdef CONFIG_MDA_CONSOLE
3757 	mda_console_init();
3758 #endif
3759 	return 0;
3760 }
3761 
3762 static const struct class vtconsole_class = {
3763 	.name = "vtconsole",
3764 };
3765 
3766 static int do_bind_con_driver(const struct consw *csw, int first, int last,
3767 			   int deflt)
3768 {
3769 	struct module *owner = csw->owner;
3770 	const char *desc = NULL;
3771 	struct con_driver *con_driver;
3772 	int i, j = -1, k = -1, retval = -ENODEV;
3773 
3774 	if (!try_module_get(owner))
3775 		return -ENODEV;
3776 
3777 	WARN_CONSOLE_UNLOCKED();
3778 
3779 	/* check if driver is registered */
3780 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3781 		con_driver = &registered_con_driver[i];
3782 
3783 		if (con_driver->con == csw) {
3784 			desc = con_driver->desc;
3785 			retval = 0;
3786 			break;
3787 		}
3788 	}
3789 
3790 	if (retval)
3791 		goto err;
3792 
3793 	if (!(con_driver->flag & CON_DRIVER_FLAG_INIT)) {
3794 		csw->con_startup();
3795 		con_driver->flag |= CON_DRIVER_FLAG_INIT;
3796 	}
3797 
3798 	if (deflt) {
3799 		if (conswitchp)
3800 			module_put(conswitchp->owner);
3801 
3802 		__module_get(owner);
3803 		conswitchp = csw;
3804 	}
3805 
3806 	first = max(first, con_driver->first);
3807 	last = min(last, con_driver->last);
3808 
3809 	for (i = first; i <= last; i++) {
3810 		int old_was_color;
3811 		struct vc_data *vc = vc_cons[i].d;
3812 
3813 		if (con_driver_map[i])
3814 			module_put(con_driver_map[i]->owner);
3815 		__module_get(owner);
3816 		con_driver_map[i] = csw;
3817 
3818 		if (!vc || !vc->vc_sw)
3819 			continue;
3820 
3821 		j = i;
3822 
3823 		if (con_is_visible(vc)) {
3824 			k = i;
3825 			save_screen(vc);
3826 		}
3827 
3828 		old_was_color = vc->vc_can_do_color;
3829 		vc->vc_sw->con_deinit(vc);
3830 		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
3831 		visual_init(vc, i, false);
3832 		set_origin(vc);
3833 		update_attr(vc);
3834 
3835 		/* If the console changed between mono <-> color, then
3836 		 * the attributes in the screenbuf will be wrong.  The
3837 		 * following resets all attributes to something sane.
3838 		 */
3839 		if (old_was_color != vc->vc_can_do_color)
3840 			clear_buffer_attributes(vc);
3841 	}
3842 
3843 	pr_info("Console: switching ");
3844 	if (!deflt)
3845 		pr_cont("consoles %d-%d ", first + 1, last + 1);
3846 	if (j >= 0) {
3847 		struct vc_data *vc = vc_cons[j].d;
3848 
3849 		pr_cont("to %s %s %dx%d\n",
3850 			vc->vc_can_do_color ? "colour" : "mono",
3851 			desc, vc->vc_cols, vc->vc_rows);
3852 
3853 		if (k >= 0) {
3854 			vc = vc_cons[k].d;
3855 			update_screen(vc);
3856 		}
3857 	} else {
3858 		pr_cont("to %s\n", desc);
3859 	}
3860 
3861 	retval = 0;
3862 err:
3863 	module_put(owner);
3864 	return retval;
3865 };
3866 
3867 
3868 #ifdef CONFIG_VT_HW_CONSOLE_BINDING
3869 int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
3870 {
3871 	struct module *owner = csw->owner;
3872 	const struct consw *defcsw = NULL;
3873 	struct con_driver *con_driver = NULL, *con_back = NULL;
3874 	int i, retval = -ENODEV;
3875 
3876 	if (!try_module_get(owner))
3877 		return -ENODEV;
3878 
3879 	WARN_CONSOLE_UNLOCKED();
3880 
3881 	/* check if driver is registered and if it is unbindable */
3882 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3883 		con_driver = &registered_con_driver[i];
3884 
3885 		if (con_driver->con == csw &&
3886 		    con_driver->flag & CON_DRIVER_FLAG_MODULE) {
3887 			retval = 0;
3888 			break;
3889 		}
3890 	}
3891 
3892 	if (retval)
3893 		goto err;
3894 
3895 	retval = -ENODEV;
3896 
3897 	/* check if backup driver exists */
3898 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3899 		con_back = &registered_con_driver[i];
3900 
3901 		if (con_back->con && con_back->con != csw) {
3902 			defcsw = con_back->con;
3903 			retval = 0;
3904 			break;
3905 		}
3906 	}
3907 
3908 	if (retval)
3909 		goto err;
3910 
3911 	if (!con_is_bound(csw))
3912 		goto err;
3913 
3914 	first = max(first, con_driver->first);
3915 	last = min(last, con_driver->last);
3916 
3917 	for (i = first; i <= last; i++) {
3918 		if (con_driver_map[i] == csw) {
3919 			module_put(csw->owner);
3920 			con_driver_map[i] = NULL;
3921 		}
3922 	}
3923 
3924 	if (!con_is_bound(defcsw)) {
3925 		const struct consw *defconsw = conswitchp;
3926 
3927 		defcsw->con_startup();
3928 		con_back->flag |= CON_DRIVER_FLAG_INIT;
3929 		/*
3930 		 * vgacon may change the default driver to point
3931 		 * to dummycon, we restore it here...
3932 		 */
3933 		conswitchp = defconsw;
3934 	}
3935 
3936 	if (!con_is_bound(csw))
3937 		con_driver->flag &= ~CON_DRIVER_FLAG_INIT;
3938 
3939 	/* ignore return value, binding should not fail */
3940 	do_bind_con_driver(defcsw, first, last, deflt);
3941 err:
3942 	module_put(owner);
3943 	return retval;
3944 
3945 }
3946 EXPORT_SYMBOL_GPL(do_unbind_con_driver);
3947 
3948 static int vt_bind(struct con_driver *con)
3949 {
3950 	const struct consw *defcsw = NULL, *csw = NULL;
3951 	int i, more = 1, first = -1, last = -1, deflt = 0;
3952 
3953  	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3954 		goto err;
3955 
3956 	csw = con->con;
3957 
3958 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3959 		struct con_driver *con = &registered_con_driver[i];
3960 
3961 		if (con->con && !(con->flag & CON_DRIVER_FLAG_MODULE)) {
3962 			defcsw = con->con;
3963 			break;
3964 		}
3965 	}
3966 
3967 	if (!defcsw)
3968 		goto err;
3969 
3970 	while (more) {
3971 		more = 0;
3972 
3973 		for (i = con->first; i <= con->last; i++) {
3974 			if (con_driver_map[i] == defcsw) {
3975 				if (first == -1)
3976 					first = i;
3977 				last = i;
3978 				more = 1;
3979 			} else if (first != -1)
3980 				break;
3981 		}
3982 
3983 		if (first == 0 && last == MAX_NR_CONSOLES -1)
3984 			deflt = 1;
3985 
3986 		if (first != -1)
3987 			do_bind_con_driver(csw, first, last, deflt);
3988 
3989 		first = -1;
3990 		last = -1;
3991 		deflt = 0;
3992 	}
3993 
3994 err:
3995 	return 0;
3996 }
3997 
3998 static int vt_unbind(struct con_driver *con)
3999 {
4000 	const struct consw *csw = NULL;
4001 	int i, more = 1, first = -1, last = -1, deflt = 0;
4002 	int ret;
4003 
4004  	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
4005 		goto err;
4006 
4007 	csw = con->con;
4008 
4009 	while (more) {
4010 		more = 0;
4011 
4012 		for (i = con->first; i <= con->last; i++) {
4013 			if (con_driver_map[i] == csw) {
4014 				if (first == -1)
4015 					first = i;
4016 				last = i;
4017 				more = 1;
4018 			} else if (first != -1)
4019 				break;
4020 		}
4021 
4022 		if (first == 0 && last == MAX_NR_CONSOLES -1)
4023 			deflt = 1;
4024 
4025 		if (first != -1) {
4026 			ret = do_unbind_con_driver(csw, first, last, deflt);
4027 			if (ret != 0)
4028 				return ret;
4029 		}
4030 
4031 		first = -1;
4032 		last = -1;
4033 		deflt = 0;
4034 	}
4035 
4036 err:
4037 	return 0;
4038 }
4039 #else
4040 static inline int vt_bind(struct con_driver *con)
4041 {
4042 	return 0;
4043 }
4044 static inline int vt_unbind(struct con_driver *con)
4045 {
4046 	return 0;
4047 }
4048 #endif /* CONFIG_VT_HW_CONSOLE_BINDING */
4049 
4050 static ssize_t store_bind(struct device *dev, struct device_attribute *attr,
4051 			  const char *buf, size_t count)
4052 {
4053 	struct con_driver *con = dev_get_drvdata(dev);
4054 	int bind = simple_strtoul(buf, NULL, 0);
4055 
4056 	console_lock();
4057 
4058 	if (bind)
4059 		vt_bind(con);
4060 	else
4061 		vt_unbind(con);
4062 
4063 	console_unlock();
4064 
4065 	return count;
4066 }
4067 
4068 static ssize_t show_bind(struct device *dev, struct device_attribute *attr,
4069 			 char *buf)
4070 {
4071 	struct con_driver *con = dev_get_drvdata(dev);
4072 	int bind;
4073 
4074 	console_lock();
4075 	bind = con_is_bound(con->con);
4076 	console_unlock();
4077 
4078 	return sysfs_emit(buf, "%i\n", bind);
4079 }
4080 
4081 static ssize_t show_name(struct device *dev, struct device_attribute *attr,
4082 			 char *buf)
4083 {
4084 	struct con_driver *con = dev_get_drvdata(dev);
4085 
4086 	return sysfs_emit(buf, "%s %s\n",
4087 			(con->flag & CON_DRIVER_FLAG_MODULE) ? "(M)" : "(S)",
4088 			 con->desc);
4089 
4090 }
4091 
4092 static DEVICE_ATTR(bind, S_IRUGO|S_IWUSR, show_bind, store_bind);
4093 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
4094 
4095 static struct attribute *con_dev_attrs[] = {
4096 	&dev_attr_bind.attr,
4097 	&dev_attr_name.attr,
4098 	NULL
4099 };
4100 
4101 ATTRIBUTE_GROUPS(con_dev);
4102 
4103 static int vtconsole_init_device(struct con_driver *con)
4104 {
4105 	con->flag |= CON_DRIVER_FLAG_ATTR;
4106 	return 0;
4107 }
4108 
4109 static void vtconsole_deinit_device(struct con_driver *con)
4110 {
4111 	con->flag &= ~CON_DRIVER_FLAG_ATTR;
4112 }
4113 
4114 /**
4115  * con_is_bound - checks if driver is bound to the console
4116  * @csw: console driver
4117  *
4118  * RETURNS: zero if unbound, nonzero if bound
4119  *
4120  * Drivers can call this and if zero, they should release
4121  * all resources allocated on &consw.con_startup()
4122  */
4123 int con_is_bound(const struct consw *csw)
4124 {
4125 	int i, bound = 0;
4126 
4127 	WARN_CONSOLE_UNLOCKED();
4128 
4129 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
4130 		if (con_driver_map[i] == csw) {
4131 			bound = 1;
4132 			break;
4133 		}
4134 	}
4135 
4136 	return bound;
4137 }
4138 EXPORT_SYMBOL(con_is_bound);
4139 
4140 /**
4141  * con_is_visible - checks whether the current console is visible
4142  * @vc: virtual console
4143  *
4144  * RETURNS: zero if not visible, nonzero if visible
4145  */
4146 bool con_is_visible(const struct vc_data *vc)
4147 {
4148 	WARN_CONSOLE_UNLOCKED();
4149 
4150 	return *vc->vc_display_fg == vc;
4151 }
4152 EXPORT_SYMBOL(con_is_visible);
4153 
4154 /**
4155  * con_debug_enter - prepare the console for the kernel debugger
4156  * @vc: virtual console
4157  *
4158  * Called when the console is taken over by the kernel debugger, this
4159  * function needs to save the current console state, then put the console
4160  * into a state suitable for the kernel debugger.
4161  */
4162 void con_debug_enter(struct vc_data *vc)
4163 {
4164 	saved_fg_console = fg_console;
4165 	saved_last_console = last_console;
4166 	saved_want_console = want_console;
4167 	saved_vc_mode = vc->vc_mode;
4168 	saved_console_blanked = console_blanked;
4169 	vc->vc_mode = KD_TEXT;
4170 	console_blanked = 0;
4171 	if (vc->vc_sw->con_debug_enter)
4172 		vc->vc_sw->con_debug_enter(vc);
4173 #ifdef CONFIG_KGDB_KDB
4174 	/* Set the initial LINES variable if it is not already set */
4175 	if (vc->vc_rows < 999) {
4176 		int linecount;
4177 		char lns[4];
4178 		const char *setargs[3] = {
4179 			"set",
4180 			"LINES",
4181 			lns,
4182 		};
4183 		if (kdbgetintenv(setargs[0], &linecount)) {
4184 			snprintf(lns, 4, "%i", vc->vc_rows);
4185 			kdb_set(2, setargs);
4186 		}
4187 	}
4188 	if (vc->vc_cols < 999) {
4189 		int colcount;
4190 		char cols[4];
4191 		const char *setargs[3] = {
4192 			"set",
4193 			"COLUMNS",
4194 			cols,
4195 		};
4196 		if (kdbgetintenv(setargs[0], &colcount)) {
4197 			snprintf(cols, 4, "%i", vc->vc_cols);
4198 			kdb_set(2, setargs);
4199 		}
4200 	}
4201 #endif /* CONFIG_KGDB_KDB */
4202 }
4203 EXPORT_SYMBOL_GPL(con_debug_enter);
4204 
4205 /**
4206  * con_debug_leave - restore console state
4207  *
4208  * Restore the console state to what it was before the kernel debugger
4209  * was invoked.
4210  */
4211 void con_debug_leave(void)
4212 {
4213 	struct vc_data *vc;
4214 
4215 	fg_console = saved_fg_console;
4216 	last_console = saved_last_console;
4217 	want_console = saved_want_console;
4218 	console_blanked = saved_console_blanked;
4219 	vc_cons[fg_console].d->vc_mode = saved_vc_mode;
4220 
4221 	vc = vc_cons[fg_console].d;
4222 	if (vc->vc_sw->con_debug_leave)
4223 		vc->vc_sw->con_debug_leave(vc);
4224 }
4225 EXPORT_SYMBOL_GPL(con_debug_leave);
4226 
4227 static int do_register_con_driver(const struct consw *csw, int first, int last)
4228 {
4229 	struct module *owner = csw->owner;
4230 	struct con_driver *con_driver;
4231 	const char *desc;
4232 	int i, retval;
4233 
4234 	WARN_CONSOLE_UNLOCKED();
4235 
4236 	if (!try_module_get(owner))
4237 		return -ENODEV;
4238 
4239 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4240 		con_driver = &registered_con_driver[i];
4241 
4242 		/* already registered */
4243 		if (con_driver->con == csw) {
4244 			retval = -EBUSY;
4245 			goto err;
4246 		}
4247 	}
4248 
4249 	desc = csw->con_startup();
4250 	if (!desc) {
4251 		retval = -ENODEV;
4252 		goto err;
4253 	}
4254 
4255 	retval = -EINVAL;
4256 
4257 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4258 		con_driver = &registered_con_driver[i];
4259 
4260 		if (con_driver->con == NULL &&
4261 		    !(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE)) {
4262 			con_driver->con = csw;
4263 			con_driver->desc = desc;
4264 			con_driver->node = i;
4265 			con_driver->flag = CON_DRIVER_FLAG_MODULE |
4266 			                   CON_DRIVER_FLAG_INIT;
4267 			con_driver->first = first;
4268 			con_driver->last = last;
4269 			retval = 0;
4270 			break;
4271 		}
4272 	}
4273 
4274 	if (retval)
4275 		goto err;
4276 
4277 	con_driver->dev =
4278 		device_create_with_groups(&vtconsole_class, NULL,
4279 					  MKDEV(0, con_driver->node),
4280 					  con_driver, con_dev_groups,
4281 					  "vtcon%i", con_driver->node);
4282 	if (IS_ERR(con_driver->dev)) {
4283 		pr_warn("Unable to create device for %s; errno = %ld\n",
4284 			con_driver->desc, PTR_ERR(con_driver->dev));
4285 		con_driver->dev = NULL;
4286 	} else {
4287 		vtconsole_init_device(con_driver);
4288 	}
4289 
4290 err:
4291 	module_put(owner);
4292 	return retval;
4293 }
4294 
4295 
4296 /**
4297  * do_unregister_con_driver - unregister console driver from console layer
4298  * @csw: console driver
4299  *
4300  * DESCRIPTION: All drivers that registers to the console layer must
4301  * call this function upon exit, or if the console driver is in a state
4302  * where it won't be able to handle console services, such as the
4303  * framebuffer console without loaded framebuffer drivers.
4304  *
4305  * The driver must unbind first prior to unregistration.
4306  */
4307 int do_unregister_con_driver(const struct consw *csw)
4308 {
4309 	int i;
4310 
4311 	/* cannot unregister a bound driver */
4312 	if (con_is_bound(csw))
4313 		return -EBUSY;
4314 
4315 	if (csw == conswitchp)
4316 		return -EINVAL;
4317 
4318 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4319 		struct con_driver *con_driver = &registered_con_driver[i];
4320 
4321 		if (con_driver->con == csw) {
4322 			/*
4323 			 * Defer the removal of the sysfs entries since that
4324 			 * will acquire the kernfs s_active lock and we can't
4325 			 * acquire this lock while holding the console lock:
4326 			 * the unbind sysfs entry imposes already the opposite
4327 			 * order. Reset con already here to prevent any later
4328 			 * lookup to succeed and mark this slot as zombie, so
4329 			 * it won't get reused until we complete the removal
4330 			 * in the deferred work.
4331 			 */
4332 			con_driver->con = NULL;
4333 			con_driver->flag = CON_DRIVER_FLAG_ZOMBIE;
4334 			schedule_work(&con_driver_unregister_work);
4335 
4336 			return 0;
4337 		}
4338 	}
4339 
4340 	return -ENODEV;
4341 }
4342 EXPORT_SYMBOL_GPL(do_unregister_con_driver);
4343 
4344 static void con_driver_unregister_callback(struct work_struct *ignored)
4345 {
4346 	int i;
4347 
4348 	console_lock();
4349 
4350 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4351 		struct con_driver *con_driver = &registered_con_driver[i];
4352 
4353 		if (!(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE))
4354 			continue;
4355 
4356 		console_unlock();
4357 
4358 		vtconsole_deinit_device(con_driver);
4359 		device_destroy(&vtconsole_class, MKDEV(0, con_driver->node));
4360 
4361 		console_lock();
4362 
4363 		if (WARN_ON_ONCE(con_driver->con))
4364 			con_driver->con = NULL;
4365 		con_driver->desc = NULL;
4366 		con_driver->dev = NULL;
4367 		con_driver->node = 0;
4368 		WARN_ON_ONCE(con_driver->flag != CON_DRIVER_FLAG_ZOMBIE);
4369 		con_driver->flag = 0;
4370 		con_driver->first = 0;
4371 		con_driver->last = 0;
4372 	}
4373 
4374 	console_unlock();
4375 }
4376 
4377 /*
4378  *	If we support more console drivers, this function is used
4379  *	when a driver wants to take over some existing consoles
4380  *	and become default driver for newly opened ones.
4381  *
4382  *	do_take_over_console is basically a register followed by bind
4383  */
4384 int do_take_over_console(const struct consw *csw, int first, int last, int deflt)
4385 {
4386 	int err;
4387 
4388 	err = do_register_con_driver(csw, first, last);
4389 	/*
4390 	 * If we get an busy error we still want to bind the console driver
4391 	 * and return success, as we may have unbound the console driver
4392 	 * but not unregistered it.
4393 	 */
4394 	if (err == -EBUSY)
4395 		err = 0;
4396 	if (!err)
4397 		do_bind_con_driver(csw, first, last, deflt);
4398 
4399 	return err;
4400 }
4401 EXPORT_SYMBOL_GPL(do_take_over_console);
4402 
4403 
4404 /*
4405  * give_up_console is a wrapper to unregister_con_driver. It will only
4406  * work if driver is fully unbound.
4407  */
4408 void give_up_console(const struct consw *csw)
4409 {
4410 	console_lock();
4411 	do_unregister_con_driver(csw);
4412 	console_unlock();
4413 }
4414 EXPORT_SYMBOL(give_up_console);
4415 
4416 static int __init vtconsole_class_init(void)
4417 {
4418 	int i;
4419 
4420 	i = class_register(&vtconsole_class);
4421 	if (i)
4422 		pr_warn("Unable to create vt console class; errno = %d\n", i);
4423 
4424 	/* Add system drivers to sysfs */
4425 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4426 		struct con_driver *con = &registered_con_driver[i];
4427 
4428 		if (con->con && !con->dev) {
4429 			con->dev =
4430 				device_create_with_groups(&vtconsole_class, NULL,
4431 							  MKDEV(0, con->node),
4432 							  con, con_dev_groups,
4433 							  "vtcon%i", con->node);
4434 
4435 			if (IS_ERR(con->dev)) {
4436 				pr_warn("Unable to create device for %s; errno = %ld\n",
4437 					con->desc, PTR_ERR(con->dev));
4438 				con->dev = NULL;
4439 			} else {
4440 				vtconsole_init_device(con);
4441 			}
4442 		}
4443 	}
4444 
4445 	return 0;
4446 }
4447 postcore_initcall(vtconsole_class_init);
4448 
4449 /*
4450  *	Screen blanking
4451  */
4452 
4453 static int set_vesa_blanking(u8 __user *mode_user)
4454 {
4455 	u8 mode;
4456 
4457 	if (get_user(mode, mode_user))
4458 		return -EFAULT;
4459 
4460 	console_lock();
4461 	vesa_blank_mode = (mode <= VESA_BLANK_MAX) ? mode : VESA_NO_BLANKING;
4462 	console_unlock();
4463 
4464 	return 0;
4465 }
4466 
4467 void do_blank_screen(int entering_gfx)
4468 {
4469 	struct vc_data *vc = vc_cons[fg_console].d;
4470 	int i;
4471 
4472 	might_sleep();
4473 
4474 	WARN_CONSOLE_UNLOCKED();
4475 
4476 	if (console_blanked) {
4477 		if (blank_state == blank_vesa_wait) {
4478 			blank_state = blank_off;
4479 			vc->vc_sw->con_blank(vc, vesa_blank_mode + 1, 0);
4480 		}
4481 		return;
4482 	}
4483 
4484 	/* entering graphics mode? */
4485 	if (entering_gfx) {
4486 		hide_cursor(vc);
4487 		save_screen(vc);
4488 		vc->vc_sw->con_blank(vc, VESA_VSYNC_SUSPEND, 1);
4489 		console_blanked = fg_console + 1;
4490 		blank_state = blank_off;
4491 		set_origin(vc);
4492 		return;
4493 	}
4494 
4495 	blank_state = blank_off;
4496 
4497 	/* don't blank graphics */
4498 	if (vc->vc_mode != KD_TEXT) {
4499 		console_blanked = fg_console + 1;
4500 		return;
4501 	}
4502 
4503 	hide_cursor(vc);
4504 	del_timer_sync(&console_timer);
4505 	blank_timer_expired = 0;
4506 
4507 	save_screen(vc);
4508 	/* In case we need to reset origin, blanking hook returns 1 */
4509 	i = vc->vc_sw->con_blank(vc, vesa_off_interval ? VESA_VSYNC_SUSPEND :
4510 				 (vesa_blank_mode + 1), 0);
4511 	console_blanked = fg_console + 1;
4512 	if (i)
4513 		set_origin(vc);
4514 
4515 	if (console_blank_hook && console_blank_hook(1))
4516 		return;
4517 
4518 	if (vesa_off_interval && vesa_blank_mode) {
4519 		blank_state = blank_vesa_wait;
4520 		mod_timer(&console_timer, jiffies + vesa_off_interval);
4521 	}
4522 	vt_event_post(VT_EVENT_BLANK, vc->vc_num, vc->vc_num);
4523 }
4524 EXPORT_SYMBOL(do_blank_screen);
4525 
4526 /*
4527  * Called by timer as well as from vt_console_driver
4528  */
4529 void do_unblank_screen(int leaving_gfx)
4530 {
4531 	struct vc_data *vc;
4532 
4533 	/* This should now always be called from a "sane" (read: can schedule)
4534 	 * context for the sake of the low level drivers, except in the special
4535 	 * case of oops_in_progress
4536 	 */
4537 	if (!oops_in_progress)
4538 		might_sleep();
4539 
4540 	WARN_CONSOLE_UNLOCKED();
4541 
4542 	ignore_poke = 0;
4543 	if (!console_blanked)
4544 		return;
4545 	if (!vc_cons_allocated(fg_console)) {
4546 		/* impossible */
4547 		pr_warn("unblank_screen: tty %d not allocated ??\n",
4548 			fg_console + 1);
4549 		return;
4550 	}
4551 	vc = vc_cons[fg_console].d;
4552 	if (vc->vc_mode != KD_TEXT)
4553 		return; /* but leave console_blanked != 0 */
4554 
4555 	if (blankinterval) {
4556 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4557 		blank_state = blank_normal_wait;
4558 	}
4559 
4560 	console_blanked = 0;
4561 	if (vc->vc_sw->con_blank(vc, VESA_NO_BLANKING, leaving_gfx))
4562 		/* Low-level driver cannot restore -> do it ourselves */
4563 		update_screen(vc);
4564 	if (console_blank_hook)
4565 		console_blank_hook(0);
4566 	set_palette(vc);
4567 	set_cursor(vc);
4568 	vt_event_post(VT_EVENT_UNBLANK, vc->vc_num, vc->vc_num);
4569 }
4570 EXPORT_SYMBOL(do_unblank_screen);
4571 
4572 /*
4573  * This is called by the outside world to cause a forced unblank, mostly for
4574  * oopses. Currently, I just call do_unblank_screen(0), but we could eventually
4575  * call it with 1 as an argument and so force a mode restore... that may kill
4576  * X or at least garbage the screen but would also make the Oops visible...
4577  */
4578 static void unblank_screen(void)
4579 {
4580 	do_unblank_screen(0);
4581 }
4582 
4583 /*
4584  * We defer the timer blanking to work queue so it can take the console mutex
4585  * (console operations can still happen at irq time, but only from printk which
4586  * has the console mutex. Not perfect yet, but better than no locking
4587  */
4588 static void blank_screen_t(struct timer_list *unused)
4589 {
4590 	blank_timer_expired = 1;
4591 	schedule_work(&console_work);
4592 }
4593 
4594 void poke_blanked_console(void)
4595 {
4596 	WARN_CONSOLE_UNLOCKED();
4597 
4598 	/* Add this so we quickly catch whoever might call us in a non
4599 	 * safe context. Nowadays, unblank_screen() isn't to be called in
4600 	 * atomic contexts and is allowed to schedule (with the special case
4601 	 * of oops_in_progress, but that isn't of any concern for this
4602 	 * function. --BenH.
4603 	 */
4604 	might_sleep();
4605 
4606 	/* This isn't perfectly race free, but a race here would be mostly harmless,
4607 	 * at worst, we'll do a spurious blank and it's unlikely
4608 	 */
4609 	del_timer(&console_timer);
4610 	blank_timer_expired = 0;
4611 
4612 	if (ignore_poke || !vc_cons[fg_console].d || vc_cons[fg_console].d->vc_mode == KD_GRAPHICS)
4613 		return;
4614 	if (console_blanked)
4615 		unblank_screen();
4616 	else if (blankinterval) {
4617 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4618 		blank_state = blank_normal_wait;
4619 	}
4620 }
4621 
4622 /*
4623  *	Palettes
4624  */
4625 
4626 static void set_palette(struct vc_data *vc)
4627 {
4628 	WARN_CONSOLE_UNLOCKED();
4629 
4630 	if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_set_palette)
4631 		vc->vc_sw->con_set_palette(vc, color_table);
4632 }
4633 
4634 /*
4635  * Load palette into the DAC registers. arg points to a colour
4636  * map, 3 bytes per colour, 16 colours, range from 0 to 255.
4637  */
4638 
4639 int con_set_cmap(unsigned char __user *arg)
4640 {
4641 	int i, j, k;
4642 	unsigned char colormap[3*16];
4643 
4644 	if (copy_from_user(colormap, arg, sizeof(colormap)))
4645 		return -EFAULT;
4646 
4647 	console_lock();
4648 	for (i = k = 0; i < 16; i++) {
4649 		default_red[i] = colormap[k++];
4650 		default_grn[i] = colormap[k++];
4651 		default_blu[i] = colormap[k++];
4652 	}
4653 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
4654 		if (!vc_cons_allocated(i))
4655 			continue;
4656 		for (j = k = 0; j < 16; j++) {
4657 			vc_cons[i].d->vc_palette[k++] = default_red[j];
4658 			vc_cons[i].d->vc_palette[k++] = default_grn[j];
4659 			vc_cons[i].d->vc_palette[k++] = default_blu[j];
4660 		}
4661 		set_palette(vc_cons[i].d);
4662 	}
4663 	console_unlock();
4664 
4665 	return 0;
4666 }
4667 
4668 int con_get_cmap(unsigned char __user *arg)
4669 {
4670 	int i, k;
4671 	unsigned char colormap[3*16];
4672 
4673 	console_lock();
4674 	for (i = k = 0; i < 16; i++) {
4675 		colormap[k++] = default_red[i];
4676 		colormap[k++] = default_grn[i];
4677 		colormap[k++] = default_blu[i];
4678 	}
4679 	console_unlock();
4680 
4681 	if (copy_to_user(arg, colormap, sizeof(colormap)))
4682 		return -EFAULT;
4683 
4684 	return 0;
4685 }
4686 
4687 void reset_palette(struct vc_data *vc)
4688 {
4689 	int j, k;
4690 	for (j=k=0; j<16; j++) {
4691 		vc->vc_palette[k++] = default_red[j];
4692 		vc->vc_palette[k++] = default_grn[j];
4693 		vc->vc_palette[k++] = default_blu[j];
4694 	}
4695 	set_palette(vc);
4696 }
4697 
4698 /*
4699  *  Font switching
4700  *
4701  *  Currently we only support fonts up to 128 pixels wide, at a maximum height
4702  *  of 128 pixels. Userspace fontdata may have to be stored with 32 bytes
4703  *  (shorts/ints, depending on width) reserved for each character which is
4704  *  kinda wasty, but this is done in order to maintain compatibility with the
4705  *  EGA/VGA fonts. It is up to the actual low-level console-driver convert data
4706  *  into its favorite format (maybe we should add a `fontoffset' field to the
4707  *  `display' structure so we won't have to convert the fontdata all the time.
4708  *  /Jes
4709  */
4710 
4711 #define max_font_width	64
4712 #define max_font_height	128
4713 #define max_font_glyphs	512
4714 #define max_font_size	(max_font_glyphs*max_font_width*max_font_height)
4715 
4716 static int con_font_get(struct vc_data *vc, struct console_font_op *op)
4717 {
4718 	struct console_font font;
4719 	int rc = -EINVAL;
4720 	int c;
4721 	unsigned int vpitch = op->op == KD_FONT_OP_GET_TALL ? op->height : 32;
4722 
4723 	if (vpitch > max_font_height)
4724 		return -EINVAL;
4725 
4726 	if (op->data) {
4727 		font.data = kvzalloc(max_font_size, GFP_KERNEL);
4728 		if (!font.data)
4729 			return -ENOMEM;
4730 	} else
4731 		font.data = NULL;
4732 
4733 	console_lock();
4734 	if (vc->vc_mode != KD_TEXT)
4735 		rc = -EINVAL;
4736 	else if (vc->vc_sw->con_font_get)
4737 		rc = vc->vc_sw->con_font_get(vc, &font, vpitch);
4738 	else
4739 		rc = -ENOSYS;
4740 	console_unlock();
4741 
4742 	if (rc)
4743 		goto out;
4744 
4745 	c = (font.width+7)/8 * vpitch * font.charcount;
4746 
4747 	if (op->data && font.charcount > op->charcount)
4748 		rc = -ENOSPC;
4749 	if (font.width > op->width || font.height > op->height)
4750 		rc = -ENOSPC;
4751 	if (rc)
4752 		goto out;
4753 
4754 	op->height = font.height;
4755 	op->width = font.width;
4756 	op->charcount = font.charcount;
4757 
4758 	if (op->data && copy_to_user(op->data, font.data, c))
4759 		rc = -EFAULT;
4760 
4761 out:
4762 	kvfree(font.data);
4763 	return rc;
4764 }
4765 
4766 static int con_font_set(struct vc_data *vc, const struct console_font_op *op)
4767 {
4768 	struct console_font font;
4769 	int rc = -EINVAL;
4770 	int size;
4771 	unsigned int vpitch = op->op == KD_FONT_OP_SET_TALL ? op->height : 32;
4772 
4773 	if (vc->vc_mode != KD_TEXT)
4774 		return -EINVAL;
4775 	if (!op->data)
4776 		return -EINVAL;
4777 	if (op->charcount > max_font_glyphs)
4778 		return -EINVAL;
4779 	if (op->width <= 0 || op->width > max_font_width || !op->height ||
4780 	    op->height > max_font_height)
4781 		return -EINVAL;
4782 	if (vpitch < op->height)
4783 		return -EINVAL;
4784 	size = (op->width+7)/8 * vpitch * op->charcount;
4785 	if (size > max_font_size)
4786 		return -ENOSPC;
4787 
4788 	font.data = memdup_user(op->data, size);
4789 	if (IS_ERR(font.data))
4790 		return PTR_ERR(font.data);
4791 
4792 	font.charcount = op->charcount;
4793 	font.width = op->width;
4794 	font.height = op->height;
4795 
4796 	console_lock();
4797 	if (vc->vc_mode != KD_TEXT)
4798 		rc = -EINVAL;
4799 	else if (vc->vc_sw->con_font_set) {
4800 		if (vc_is_sel(vc))
4801 			clear_selection();
4802 		rc = vc->vc_sw->con_font_set(vc, &font, vpitch, op->flags);
4803 	} else
4804 		rc = -ENOSYS;
4805 	console_unlock();
4806 	kfree(font.data);
4807 	return rc;
4808 }
4809 
4810 static int con_font_default(struct vc_data *vc, struct console_font_op *op)
4811 {
4812 	struct console_font font = {.width = op->width, .height = op->height};
4813 	char name[MAX_FONT_NAME];
4814 	char *s = name;
4815 	int rc;
4816 
4817 
4818 	if (!op->data)
4819 		s = NULL;
4820 	else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0)
4821 		return -EFAULT;
4822 	else
4823 		name[MAX_FONT_NAME - 1] = 0;
4824 
4825 	console_lock();
4826 	if (vc->vc_mode != KD_TEXT) {
4827 		console_unlock();
4828 		return -EINVAL;
4829 	}
4830 	if (vc->vc_sw->con_font_default) {
4831 		if (vc_is_sel(vc))
4832 			clear_selection();
4833 		rc = vc->vc_sw->con_font_default(vc, &font, s);
4834 	} else
4835 		rc = -ENOSYS;
4836 	console_unlock();
4837 	if (!rc) {
4838 		op->width = font.width;
4839 		op->height = font.height;
4840 	}
4841 	return rc;
4842 }
4843 
4844 int con_font_op(struct vc_data *vc, struct console_font_op *op)
4845 {
4846 	switch (op->op) {
4847 	case KD_FONT_OP_SET:
4848 	case KD_FONT_OP_SET_TALL:
4849 		return con_font_set(vc, op);
4850 	case KD_FONT_OP_GET:
4851 	case KD_FONT_OP_GET_TALL:
4852 		return con_font_get(vc, op);
4853 	case KD_FONT_OP_SET_DEFAULT:
4854 		return con_font_default(vc, op);
4855 	case KD_FONT_OP_COPY:
4856 		/* was buggy and never really used */
4857 		return -EINVAL;
4858 	}
4859 	return -ENOSYS;
4860 }
4861 
4862 /*
4863  *	Interface exported to selection and vcs.
4864  */
4865 
4866 /* used by selection */
4867 u16 screen_glyph(const struct vc_data *vc, int offset)
4868 {
4869 	u16 w = scr_readw(screenpos(vc, offset, true));
4870 	u16 c = w & 0xff;
4871 
4872 	if (w & vc->vc_hi_font_mask)
4873 		c |= 0x100;
4874 	return c;
4875 }
4876 EXPORT_SYMBOL_GPL(screen_glyph);
4877 
4878 u32 screen_glyph_unicode(const struct vc_data *vc, int n)
4879 {
4880 	u32 **uni_lines = vc->vc_uni_lines;
4881 
4882 	if (uni_lines)
4883 		return uni_lines[n / vc->vc_cols][n % vc->vc_cols];
4884 
4885 	return inverse_translate(vc, screen_glyph(vc, n * 2), true);
4886 }
4887 EXPORT_SYMBOL_GPL(screen_glyph_unicode);
4888 
4889 /* used by vcs - note the word offset */
4890 unsigned short *screen_pos(const struct vc_data *vc, int w_offset, bool viewed)
4891 {
4892 	return screenpos(vc, 2 * w_offset, viewed);
4893 }
4894 EXPORT_SYMBOL_GPL(screen_pos);
4895 
4896 void getconsxy(const struct vc_data *vc, unsigned char xy[static 2])
4897 {
4898 	/* clamp values if they don't fit */
4899 	xy[0] = min(vc->state.x, 0xFFu);
4900 	xy[1] = min(vc->state.y, 0xFFu);
4901 }
4902 
4903 void putconsxy(struct vc_data *vc, unsigned char xy[static const 2])
4904 {
4905 	hide_cursor(vc);
4906 	gotoxy(vc, xy[0], xy[1]);
4907 	set_cursor(vc);
4908 }
4909 
4910 u16 vcs_scr_readw(const struct vc_data *vc, const u16 *org)
4911 {
4912 	if ((unsigned long)org == vc->vc_pos && softcursor_original != -1)
4913 		return softcursor_original;
4914 	return scr_readw(org);
4915 }
4916 
4917 void vcs_scr_writew(struct vc_data *vc, u16 val, u16 *org)
4918 {
4919 	scr_writew(val, org);
4920 	if ((unsigned long)org == vc->vc_pos) {
4921 		softcursor_original = -1;
4922 		add_softcursor(vc);
4923 	}
4924 }
4925 
4926 void vcs_scr_updated(struct vc_data *vc)
4927 {
4928 	notify_update(vc);
4929 }
4930