xref: /kernel/linux/linux-6.6/drivers/tty/vt/vt.c (revision 62306a36)
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
117struct 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
127static struct con_driver registered_con_driver[MAX_NR_CON_DRIVER];
128const 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
137struct vc vc_cons [MAX_NR_CONSOLES];
138EXPORT_SYMBOL(vc_cons);
139
140static const struct consw *con_driver_map[MAX_NR_CONSOLES];
141
142static int con_open(struct tty_struct *, struct file *);
143static void vc_init(struct vc_data *vc, int do_clear);
144static void gotoxy(struct vc_data *vc, int new_x, int new_y);
145static void save_cur(struct vc_data *vc);
146static void reset_terminal(struct vc_data *vc, int do_clear);
147static void con_flush_chars(struct tty_struct *tty);
148static int set_vesa_blanking(char __user *p);
149static void set_cursor(struct vc_data *vc);
150static void hide_cursor(struct vc_data *vc);
151static void console_callback(struct work_struct *ignored);
152static void con_driver_unregister_callback(struct work_struct *ignored);
153static void blank_screen_t(struct timer_list *unused);
154static void set_palette(struct vc_data *vc);
155static void unblank_screen(void);
156
157#define vt_get_kmsg_redirect() vt_kmsg_redirect(-1)
158
159int default_utf8 = true;
160module_param(default_utf8, int, S_IRUGO | S_IWUSR);
161int global_cursor_default = -1;
162module_param(global_cursor_default, int, S_IRUGO | S_IWUSR);
163EXPORT_SYMBOL(global_cursor_default);
164
165static int cur_default = CUR_UNDERLINE;
166module_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 */
172static int ignore_poke;
173
174int do_poke_blanked_console;
175int console_blanked;
176EXPORT_SYMBOL(console_blanked);
177
178static int vesa_blank_mode; /* 0:none 1:suspendV 2:suspendH 3:powerdown */
179static int vesa_off_interval;
180static int blankinterval;
181core_param(consoleblank, blankinterval, int, 0444);
182
183static DECLARE_WORK(console_work, console_callback);
184static 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 */
192int fg_console;
193EXPORT_SYMBOL(fg_console);
194int last_console;
195int want_console = -1;
196
197static int saved_fg_console;
198static int saved_last_console;
199static int saved_want_console;
200static int saved_vc_mode;
201static 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 */
209static 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 */
221static int scrollback_delta;
222
223/*
224 * Hook so that the power management routines can (un)blank
225 * the console on our behalf.
226 */
227int (*console_blank_hook)(int);
228EXPORT_SYMBOL(console_blank_hook);
229
230static DEFINE_TIMER(console_timer, blank_screen_t);
231static int blank_state;
232static int blank_timer_expired;
233enum {
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 */
245static struct device *tty0dev;
246
247/*
248 * Notifier list for console events.
249 */
250static ATOMIC_NOTIFIER_HEAD(vt_notifier_list);
251
252int register_vt_notifier(struct notifier_block *nb)
253{
254	return atomic_notifier_chain_register(&vt_notifier_list, nb);
255}
256EXPORT_SYMBOL_GPL(register_vt_notifier);
257
258int unregister_vt_notifier(struct notifier_block *nb)
259{
260	return atomic_notifier_chain_unregister(&vt_notifier_list, nb);
261}
262EXPORT_SYMBOL_GPL(unregister_vt_notifier);
263
264static 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
270static 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
279static inline bool con_is_fg(const struct vc_data *vc)
280{
281	return vc->vc_num == fg_console;
282}
283
284static inline bool con_should_update(const struct vc_data *vc)
285{
286	return con_is_visible(vc) && !console_blanked;
287}
288
289static inline unsigned short *screenpos(const struct vc_data *vc, int offset,
290		bool viewed)
291{
292	unsigned short *p;
293
294	if (!viewed)
295		p = (unsigned short *)(vc->vc_origin + offset);
296	else if (!vc->vc_sw->con_screen_pos)
297		p = (unsigned short *)(vc->vc_visible_origin + offset);
298	else
299		p = vc->vc_sw->con_screen_pos(vc, offset);
300	return p;
301}
302
303/* Called  from the keyboard irq path.. */
304static inline void scrolldelta(int lines)
305{
306	/* FIXME */
307	/* scrolldelta needs some kind of consistency lock, but the BKL was
308	   and still is not protecting versus the scheduled back end */
309	scrollback_delta += lines;
310	schedule_console_callback();
311}
312
313void schedule_console_callback(void)
314{
315	schedule_work(&console_work);
316}
317
318/*
319 * Code to manage unicode-based screen buffers
320 */
321
322/*
323 * Our screen buffer is preceded by an array of line pointers so that
324 * scrolling only implies some pointer shuffling.
325 */
326
327static u32 **vc_uniscr_alloc(unsigned int cols, unsigned int rows)
328{
329	u32 **uni_lines;
330	void *p;
331	unsigned int memsize, i, col_size = cols * sizeof(**uni_lines);
332
333	/* allocate everything in one go */
334	memsize = col_size * rows;
335	memsize += rows * sizeof(*uni_lines);
336	uni_lines = vzalloc(memsize);
337	if (!uni_lines)
338		return NULL;
339
340	/* initial line pointers */
341	p = uni_lines + rows;
342	for (i = 0; i < rows; i++) {
343		uni_lines[i] = p;
344		p += col_size;
345	}
346
347	return uni_lines;
348}
349
350static void vc_uniscr_free(u32 **uni_lines)
351{
352	vfree(uni_lines);
353}
354
355static void vc_uniscr_set(struct vc_data *vc, u32 **new_uni_lines)
356{
357	vc_uniscr_free(vc->vc_uni_lines);
358	vc->vc_uni_lines = new_uni_lines;
359}
360
361static void vc_uniscr_putc(struct vc_data *vc, u32 uc)
362{
363	if (vc->vc_uni_lines)
364		vc->vc_uni_lines[vc->state.y][vc->state.x] = uc;
365}
366
367static void vc_uniscr_insert(struct vc_data *vc, unsigned int nr)
368{
369	if (vc->vc_uni_lines) {
370		u32 *ln = vc->vc_uni_lines[vc->state.y];
371		unsigned int x = vc->state.x, cols = vc->vc_cols;
372
373		memmove(&ln[x + nr], &ln[x], (cols - x - nr) * sizeof(*ln));
374		memset32(&ln[x], ' ', nr);
375	}
376}
377
378static void vc_uniscr_delete(struct vc_data *vc, unsigned int nr)
379{
380	if (vc->vc_uni_lines) {
381		u32 *ln = vc->vc_uni_lines[vc->state.y];
382		unsigned int x = vc->state.x, cols = vc->vc_cols;
383
384		memcpy(&ln[x], &ln[x + nr], (cols - x - nr) * sizeof(*ln));
385		memset32(&ln[cols - nr], ' ', nr);
386	}
387}
388
389static void vc_uniscr_clear_line(struct vc_data *vc, unsigned int x,
390				 unsigned int nr)
391{
392	if (vc->vc_uni_lines)
393		memset32(&vc->vc_uni_lines[vc->state.y][x], ' ', nr);
394}
395
396static void vc_uniscr_clear_lines(struct vc_data *vc, unsigned int y,
397				  unsigned int nr)
398{
399	if (vc->vc_uni_lines)
400		while (nr--)
401			memset32(vc->vc_uni_lines[y++], ' ', vc->vc_cols);
402}
403
404/* juggling array rotation algorithm (complexity O(N), size complexity O(1)) */
405static void juggle_array(u32 **array, unsigned int size, unsigned int nr)
406{
407	unsigned int gcd_idx;
408
409	for (gcd_idx = 0; gcd_idx < gcd(nr, size); gcd_idx++) {
410		u32 *gcd_idx_val = array[gcd_idx];
411		unsigned int dst_idx = gcd_idx;
412
413		while (1) {
414			unsigned int src_idx = (dst_idx + nr) % size;
415			if (src_idx == gcd_idx)
416				break;
417
418			array[dst_idx] = array[src_idx];
419			dst_idx = src_idx;
420		}
421
422		array[dst_idx] = gcd_idx_val;
423	}
424}
425
426static void vc_uniscr_scroll(struct vc_data *vc, unsigned int top,
427			     unsigned int bottom, enum con_scroll dir,
428			     unsigned int nr)
429{
430	u32 **uni_lines = vc->vc_uni_lines;
431	unsigned int size = bottom - top;
432
433	if (!uni_lines)
434		return;
435
436	if (dir == SM_DOWN) {
437		juggle_array(&uni_lines[top], size, size - nr);
438		vc_uniscr_clear_lines(vc, top, nr);
439	} else {
440		juggle_array(&uni_lines[top], size, nr);
441		vc_uniscr_clear_lines(vc, bottom - nr, nr);
442	}
443}
444
445static void vc_uniscr_copy_area(u32 **dst_lines,
446				unsigned int dst_cols,
447				unsigned int dst_rows,
448				u32 **src_lines,
449				unsigned int src_cols,
450				unsigned int src_top_row,
451				unsigned int src_bot_row)
452{
453	unsigned int dst_row = 0;
454
455	if (!dst_lines)
456		return;
457
458	while (src_top_row < src_bot_row) {
459		u32 *src_line = src_lines[src_top_row];
460		u32 *dst_line = dst_lines[dst_row];
461
462		memcpy(dst_line, src_line, src_cols * sizeof(*src_line));
463		if (dst_cols - src_cols)
464			memset32(dst_line + src_cols, ' ', dst_cols - src_cols);
465		src_top_row++;
466		dst_row++;
467	}
468	while (dst_row < dst_rows) {
469		u32 *dst_line = dst_lines[dst_row];
470
471		memset32(dst_line, ' ', dst_cols);
472		dst_row++;
473	}
474}
475
476/*
477 * Called from vcs_read() to make sure unicode screen retrieval is possible.
478 * This will initialize the unicode screen buffer if not already done.
479 * This returns 0 if OK, or a negative error code otherwise.
480 * In particular, -ENODATA is returned if the console is not in UTF-8 mode.
481 */
482int vc_uniscr_check(struct vc_data *vc)
483{
484	u32 **uni_lines;
485	unsigned short *p;
486	int x, y, mask;
487
488	WARN_CONSOLE_UNLOCKED();
489
490	if (!vc->vc_utf)
491		return -ENODATA;
492
493	if (vc->vc_uni_lines)
494		return 0;
495
496	uni_lines = vc_uniscr_alloc(vc->vc_cols, vc->vc_rows);
497	if (!uni_lines)
498		return -ENOMEM;
499
500	/*
501	 * Let's populate it initially with (imperfect) reverse translation.
502	 * This is the next best thing we can do short of having it enabled
503	 * from the start even when no users rely on this functionality. True
504	 * unicode content will be available after a complete screen refresh.
505	 */
506	p = (unsigned short *)vc->vc_origin;
507	mask = vc->vc_hi_font_mask | 0xff;
508	for (y = 0; y < vc->vc_rows; y++) {
509		u32 *line = uni_lines[y];
510		for (x = 0; x < vc->vc_cols; x++) {
511			u16 glyph = scr_readw(p++) & mask;
512			line[x] = inverse_translate(vc, glyph, true);
513		}
514	}
515
516	vc->vc_uni_lines = uni_lines;
517
518	return 0;
519}
520
521/*
522 * Called from vcs_read() to get the unicode data from the screen.
523 * This must be preceded by a successful call to vc_uniscr_check() once
524 * the console lock has been taken.
525 */
526void vc_uniscr_copy_line(const struct vc_data *vc, void *dest, bool viewed,
527			 unsigned int row, unsigned int col, unsigned int nr)
528{
529	u32 **uni_lines = vc->vc_uni_lines;
530	int offset = row * vc->vc_size_row + col * 2;
531	unsigned long pos;
532
533	if (WARN_ON_ONCE(!uni_lines))
534		return;
535
536	pos = (unsigned long)screenpos(vc, offset, viewed);
537	if (pos >= vc->vc_origin && pos < vc->vc_scr_end) {
538		/*
539		 * Desired position falls in the main screen buffer.
540		 * However the actual row/col might be different if
541		 * scrollback is active.
542		 */
543		row = (pos - vc->vc_origin) / vc->vc_size_row;
544		col = ((pos - vc->vc_origin) % vc->vc_size_row) / 2;
545		memcpy(dest, &uni_lines[row][col], nr * sizeof(u32));
546	} else {
547		/*
548		 * Scrollback is active. For now let's simply backtranslate
549		 * the screen glyphs until the unicode screen buffer does
550		 * synchronize with console display drivers for a scrollback
551		 * buffer of its own.
552		 */
553		u16 *p = (u16 *)pos;
554		int mask = vc->vc_hi_font_mask | 0xff;
555		u32 *uni_buf = dest;
556		while (nr--) {
557			u16 glyph = scr_readw(p++) & mask;
558			*uni_buf++ = inverse_translate(vc, glyph, true);
559		}
560	}
561}
562
563static void con_scroll(struct vc_data *vc, unsigned int top,
564		       unsigned int bottom, enum con_scroll dir,
565		       unsigned int nr)
566{
567	unsigned int rows = bottom - top;
568	u16 *clear, *dst, *src;
569
570	if (top + nr >= bottom)
571		nr = rows - 1;
572	if (bottom > vc->vc_rows || top >= bottom || nr < 1)
573		return;
574
575	vc_uniscr_scroll(vc, top, bottom, dir, nr);
576	if (con_is_visible(vc) &&
577			vc->vc_sw->con_scroll(vc, top, bottom, dir, nr))
578		return;
579
580	src = clear = (u16 *)(vc->vc_origin + vc->vc_size_row * top);
581	dst = (u16 *)(vc->vc_origin + vc->vc_size_row * (top + nr));
582
583	if (dir == SM_UP) {
584		clear = src + (rows - nr) * vc->vc_cols;
585		swap(src, dst);
586	}
587	scr_memmovew(dst, src, (rows - nr) * vc->vc_size_row);
588	scr_memsetw(clear, vc->vc_video_erase_char, vc->vc_size_row * nr);
589}
590
591static void do_update_region(struct vc_data *vc, unsigned long start, int count)
592{
593	unsigned int xx, yy, offset;
594	u16 *p;
595
596	p = (u16 *) start;
597	if (!vc->vc_sw->con_getxy) {
598		offset = (start - vc->vc_origin) / 2;
599		xx = offset % vc->vc_cols;
600		yy = offset / vc->vc_cols;
601	} else {
602		int nxx, nyy;
603		start = vc->vc_sw->con_getxy(vc, start, &nxx, &nyy);
604		xx = nxx; yy = nyy;
605	}
606	for(;;) {
607		u16 attrib = scr_readw(p) & 0xff00;
608		int startx = xx;
609		u16 *q = p;
610		while (xx < vc->vc_cols && count) {
611			if (attrib != (scr_readw(p) & 0xff00)) {
612				if (p > q)
613					vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
614				startx = xx;
615				q = p;
616				attrib = scr_readw(p) & 0xff00;
617			}
618			p++;
619			xx++;
620			count--;
621		}
622		if (p > q)
623			vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
624		if (!count)
625			break;
626		xx = 0;
627		yy++;
628		if (vc->vc_sw->con_getxy) {
629			p = (u16 *)start;
630			start = vc->vc_sw->con_getxy(vc, start, NULL, NULL);
631		}
632	}
633}
634
635void update_region(struct vc_data *vc, unsigned long start, int count)
636{
637	WARN_CONSOLE_UNLOCKED();
638
639	if (con_should_update(vc)) {
640		hide_cursor(vc);
641		do_update_region(vc, start, count);
642		set_cursor(vc);
643	}
644}
645EXPORT_SYMBOL(update_region);
646
647/* Structure of attributes is hardware-dependent */
648
649static u8 build_attr(struct vc_data *vc, u8 _color,
650		enum vc_intensity _intensity, bool _blink, bool _underline,
651		bool _reverse, bool _italic)
652{
653	if (vc->vc_sw->con_build_attr)
654		return vc->vc_sw->con_build_attr(vc, _color, _intensity,
655		       _blink, _underline, _reverse, _italic);
656
657/*
658 * ++roman: I completely changed the attribute format for monochrome
659 * mode (!can_do_color). The formerly used MDA (monochrome display
660 * adapter) format didn't allow the combination of certain effects.
661 * Now the attribute is just a bit vector:
662 *  Bit 0..1: intensity (0..2)
663 *  Bit 2   : underline
664 *  Bit 3   : reverse
665 *  Bit 7   : blink
666 */
667	{
668	u8 a = _color;
669	if (!vc->vc_can_do_color)
670		return _intensity |
671		       (_italic    << 1) |
672		       (_underline << 2) |
673		       (_reverse   << 3) |
674		       (_blink     << 7);
675	if (_italic)
676		a = (a & 0xF0) | vc->vc_itcolor;
677	else if (_underline)
678		a = (a & 0xf0) | vc->vc_ulcolor;
679	else if (_intensity == VCI_HALF_BRIGHT)
680		a = (a & 0xf0) | vc->vc_halfcolor;
681	if (_reverse)
682		a = (a & 0x88) | (((a >> 4) | (a << 4)) & 0x77);
683	if (_blink)
684		a ^= 0x80;
685	if (_intensity == VCI_BOLD)
686		a ^= 0x08;
687	if (vc->vc_hi_font_mask == 0x100)
688		a <<= 1;
689	return a;
690	}
691}
692
693static void update_attr(struct vc_data *vc)
694{
695	vc->vc_attr = build_attr(vc, vc->state.color, vc->state.intensity,
696	              vc->state.blink, vc->state.underline,
697	              vc->state.reverse ^ vc->vc_decscnm, vc->state.italic);
698	vc->vc_video_erase_char = ' ' | (build_attr(vc, vc->state.color,
699				VCI_NORMAL, vc->state.blink, false,
700				vc->vc_decscnm, false) << 8);
701}
702
703/* Note: inverting the screen twice should revert to the original state */
704void invert_screen(struct vc_data *vc, int offset, int count, bool viewed)
705{
706	unsigned short *p;
707
708	WARN_CONSOLE_UNLOCKED();
709
710	count /= 2;
711	p = screenpos(vc, offset, viewed);
712	if (vc->vc_sw->con_invert_region) {
713		vc->vc_sw->con_invert_region(vc, p, count);
714	} else {
715		u16 *q = p;
716		int cnt = count;
717		u16 a;
718
719		if (!vc->vc_can_do_color) {
720			while (cnt--) {
721			    a = scr_readw(q);
722			    a ^= 0x0800;
723			    scr_writew(a, q);
724			    q++;
725			}
726		} else if (vc->vc_hi_font_mask == 0x100) {
727			while (cnt--) {
728				a = scr_readw(q);
729				a = (a & 0x11ff) |
730				   ((a & 0xe000) >> 4) |
731				   ((a & 0x0e00) << 4);
732				scr_writew(a, q);
733				q++;
734			}
735		} else {
736			while (cnt--) {
737				a = scr_readw(q);
738				a = (a & 0x88ff) |
739				   ((a & 0x7000) >> 4) |
740				   ((a & 0x0700) << 4);
741				scr_writew(a, q);
742				q++;
743			}
744		}
745	}
746
747	if (con_should_update(vc))
748		do_update_region(vc, (unsigned long) p, count);
749	notify_update(vc);
750}
751
752/* used by selection: complement pointer position */
753void complement_pos(struct vc_data *vc, int offset)
754{
755	static int old_offset = -1;
756	static unsigned short old;
757	static unsigned short oldx, oldy;
758
759	WARN_CONSOLE_UNLOCKED();
760
761	if (old_offset != -1 && old_offset >= 0 &&
762	    old_offset < vc->vc_screenbuf_size) {
763		scr_writew(old, screenpos(vc, old_offset, true));
764		if (con_should_update(vc))
765			vc->vc_sw->con_putc(vc, old, oldy, oldx);
766		notify_update(vc);
767	}
768
769	old_offset = offset;
770
771	if (offset != -1 && offset >= 0 &&
772	    offset < vc->vc_screenbuf_size) {
773		unsigned short new;
774		unsigned short *p;
775		p = screenpos(vc, offset, true);
776		old = scr_readw(p);
777		new = old ^ vc->vc_complement_mask;
778		scr_writew(new, p);
779		if (con_should_update(vc)) {
780			oldx = (offset >> 1) % vc->vc_cols;
781			oldy = (offset >> 1) / vc->vc_cols;
782			vc->vc_sw->con_putc(vc, new, oldy, oldx);
783		}
784		notify_update(vc);
785	}
786}
787
788static void insert_char(struct vc_data *vc, unsigned int nr)
789{
790	unsigned short *p = (unsigned short *) vc->vc_pos;
791
792	vc_uniscr_insert(vc, nr);
793	scr_memmovew(p + nr, p, (vc->vc_cols - vc->state.x - nr) * 2);
794	scr_memsetw(p, vc->vc_video_erase_char, nr * 2);
795	vc->vc_need_wrap = 0;
796	if (con_should_update(vc))
797		do_update_region(vc, (unsigned long) p,
798			vc->vc_cols - vc->state.x);
799}
800
801static void delete_char(struct vc_data *vc, unsigned int nr)
802{
803	unsigned short *p = (unsigned short *) vc->vc_pos;
804
805	vc_uniscr_delete(vc, nr);
806	scr_memmovew(p, p + nr, (vc->vc_cols - vc->state.x - nr) * 2);
807	scr_memsetw(p + vc->vc_cols - vc->state.x - nr, vc->vc_video_erase_char,
808			nr * 2);
809	vc->vc_need_wrap = 0;
810	if (con_should_update(vc))
811		do_update_region(vc, (unsigned long) p,
812			vc->vc_cols - vc->state.x);
813}
814
815static int softcursor_original = -1;
816
817static void add_softcursor(struct vc_data *vc)
818{
819	int i = scr_readw((u16 *) vc->vc_pos);
820	u32 type = vc->vc_cursor_type;
821
822	if (!(type & CUR_SW))
823		return;
824	if (softcursor_original != -1)
825		return;
826	softcursor_original = i;
827	i |= CUR_SET(type);
828	i ^= CUR_CHANGE(type);
829	if ((type & CUR_ALWAYS_BG) &&
830			(softcursor_original & CUR_BG) == (i & CUR_BG))
831		i ^= CUR_BG;
832	if ((type & CUR_INVERT_FG_BG) && (i & CUR_FG) == ((i & CUR_BG) >> 4))
833		i ^= CUR_FG;
834	scr_writew(i, (u16 *)vc->vc_pos);
835	if (con_should_update(vc))
836		vc->vc_sw->con_putc(vc, i, vc->state.y, vc->state.x);
837}
838
839static void hide_softcursor(struct vc_data *vc)
840{
841	if (softcursor_original != -1) {
842		scr_writew(softcursor_original, (u16 *)vc->vc_pos);
843		if (con_should_update(vc))
844			vc->vc_sw->con_putc(vc, softcursor_original,
845					vc->state.y, vc->state.x);
846		softcursor_original = -1;
847	}
848}
849
850static void hide_cursor(struct vc_data *vc)
851{
852	if (vc_is_sel(vc))
853		clear_selection();
854
855	vc->vc_sw->con_cursor(vc, CM_ERASE);
856	hide_softcursor(vc);
857}
858
859static void set_cursor(struct vc_data *vc)
860{
861	if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS)
862		return;
863	if (vc->vc_deccm) {
864		if (vc_is_sel(vc))
865			clear_selection();
866		add_softcursor(vc);
867		if (CUR_SIZE(vc->vc_cursor_type) != CUR_NONE)
868			vc->vc_sw->con_cursor(vc, CM_DRAW);
869	} else
870		hide_cursor(vc);
871}
872
873static void set_origin(struct vc_data *vc)
874{
875	WARN_CONSOLE_UNLOCKED();
876
877	if (!con_is_visible(vc) ||
878	    !vc->vc_sw->con_set_origin ||
879	    !vc->vc_sw->con_set_origin(vc))
880		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
881	vc->vc_visible_origin = vc->vc_origin;
882	vc->vc_scr_end = vc->vc_origin + vc->vc_screenbuf_size;
883	vc->vc_pos = vc->vc_origin + vc->vc_size_row * vc->state.y +
884		2 * vc->state.x;
885}
886
887static void save_screen(struct vc_data *vc)
888{
889	WARN_CONSOLE_UNLOCKED();
890
891	if (vc->vc_sw->con_save_screen)
892		vc->vc_sw->con_save_screen(vc);
893}
894
895static void flush_scrollback(struct vc_data *vc)
896{
897	WARN_CONSOLE_UNLOCKED();
898
899	set_origin(vc);
900	if (vc->vc_sw->con_flush_scrollback) {
901		vc->vc_sw->con_flush_scrollback(vc);
902	} else if (con_is_visible(vc)) {
903		/*
904		 * When no con_flush_scrollback method is provided then the
905		 * legacy way for flushing the scrollback buffer is to use
906		 * a side effect of the con_switch method. We do it only on
907		 * the foreground console as background consoles have no
908		 * scrollback buffers in that case and we obviously don't
909		 * want to switch to them.
910		 */
911		hide_cursor(vc);
912		vc->vc_sw->con_switch(vc);
913		set_cursor(vc);
914	}
915}
916
917/*
918 *	Redrawing of screen
919 */
920
921void clear_buffer_attributes(struct vc_data *vc)
922{
923	unsigned short *p = (unsigned short *)vc->vc_origin;
924	int count = vc->vc_screenbuf_size / 2;
925	int mask = vc->vc_hi_font_mask | 0xff;
926
927	for (; count > 0; count--, p++) {
928		scr_writew((scr_readw(p)&mask) | (vc->vc_video_erase_char & ~mask), p);
929	}
930}
931
932void redraw_screen(struct vc_data *vc, int is_switch)
933{
934	int redraw = 0;
935
936	WARN_CONSOLE_UNLOCKED();
937
938	if (!vc) {
939		/* strange ... */
940		/* printk("redraw_screen: tty %d not allocated ??\n", new_console+1); */
941		return;
942	}
943
944	if (is_switch) {
945		struct vc_data *old_vc = vc_cons[fg_console].d;
946		if (old_vc == vc)
947			return;
948		if (!con_is_visible(vc))
949			redraw = 1;
950		*vc->vc_display_fg = vc;
951		fg_console = vc->vc_num;
952		hide_cursor(old_vc);
953		if (!con_is_visible(old_vc)) {
954			save_screen(old_vc);
955			set_origin(old_vc);
956		}
957		if (tty0dev)
958			sysfs_notify(&tty0dev->kobj, NULL, "active");
959	} else {
960		hide_cursor(vc);
961		redraw = 1;
962	}
963
964	if (redraw) {
965		int update;
966		int old_was_color = vc->vc_can_do_color;
967
968		set_origin(vc);
969		update = vc->vc_sw->con_switch(vc);
970		set_palette(vc);
971		/*
972		 * If console changed from mono<->color, the best we can do
973		 * is to clear the buffer attributes. As it currently stands,
974		 * rebuilding new attributes from the old buffer is not doable
975		 * without overly complex code.
976		 */
977		if (old_was_color != vc->vc_can_do_color) {
978			update_attr(vc);
979			clear_buffer_attributes(vc);
980		}
981
982		if (update && vc->vc_mode != KD_GRAPHICS)
983			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
984	}
985	set_cursor(vc);
986	if (is_switch) {
987		vt_set_leds_compute_shiftstate();
988		notify_update(vc);
989	}
990}
991EXPORT_SYMBOL(redraw_screen);
992
993/*
994 *	Allocation, freeing and resizing of VTs.
995 */
996
997int vc_cons_allocated(unsigned int i)
998{
999	return (i < MAX_NR_CONSOLES && vc_cons[i].d);
1000}
1001
1002static void visual_init(struct vc_data *vc, int num, int init)
1003{
1004	/* ++Geert: vc->vc_sw->con_init determines console size */
1005	if (vc->vc_sw)
1006		module_put(vc->vc_sw->owner);
1007	vc->vc_sw = conswitchp;
1008
1009	if (con_driver_map[num])
1010		vc->vc_sw = con_driver_map[num];
1011
1012	__module_get(vc->vc_sw->owner);
1013	vc->vc_num = num;
1014	vc->vc_display_fg = &master_display_fg;
1015	if (vc->uni_pagedict_loc)
1016		con_free_unimap(vc);
1017	vc->uni_pagedict_loc = &vc->uni_pagedict;
1018	vc->uni_pagedict = NULL;
1019	vc->vc_hi_font_mask = 0;
1020	vc->vc_complement_mask = 0;
1021	vc->vc_can_do_color = 0;
1022	vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1023	vc->vc_sw->con_init(vc, init);
1024	if (!vc->vc_complement_mask)
1025		vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
1026	vc->vc_s_complement_mask = vc->vc_complement_mask;
1027	vc->vc_size_row = vc->vc_cols << 1;
1028	vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
1029}
1030
1031
1032static void visual_deinit(struct vc_data *vc)
1033{
1034	vc->vc_sw->con_deinit(vc);
1035	module_put(vc->vc_sw->owner);
1036}
1037
1038static void vc_port_destruct(struct tty_port *port)
1039{
1040	struct vc_data *vc = container_of(port, struct vc_data, port);
1041
1042	kfree(vc);
1043}
1044
1045static const struct tty_port_operations vc_port_ops = {
1046	.destruct = vc_port_destruct,
1047};
1048
1049/*
1050 * Change # of rows and columns (0 means unchanged/the size of fg_console)
1051 * [this is to be used together with some user program
1052 * like resize that changes the hardware videomode]
1053 */
1054#define VC_MAXCOL (32767)
1055#define VC_MAXROW (32767)
1056
1057int vc_allocate(unsigned int currcons)	/* return 0 on success */
1058{
1059	struct vt_notifier_param param;
1060	struct vc_data *vc;
1061	int err;
1062
1063	WARN_CONSOLE_UNLOCKED();
1064
1065	if (currcons >= MAX_NR_CONSOLES)
1066		return -ENXIO;
1067
1068	if (vc_cons[currcons].d)
1069		return 0;
1070
1071	/* due to the granularity of kmalloc, we waste some memory here */
1072	/* the alloc is done in two steps, to optimize the common situation
1073	   of a 25x80 console (structsize=216, screenbuf_size=4000) */
1074	/* although the numbers above are not valid since long ago, the
1075	   point is still up-to-date and the comment still has its value
1076	   even if only as a historical artifact.  --mj, July 1998 */
1077	param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL);
1078	if (!vc)
1079		return -ENOMEM;
1080
1081	vc_cons[currcons].d = vc;
1082	tty_port_init(&vc->port);
1083	vc->port.ops = &vc_port_ops;
1084	INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
1085
1086	visual_init(vc, currcons, 1);
1087
1088	if (!*vc->uni_pagedict_loc)
1089		con_set_default_unimap(vc);
1090
1091	err = -EINVAL;
1092	if (vc->vc_cols > VC_MAXCOL || vc->vc_rows > VC_MAXROW ||
1093	    vc->vc_screenbuf_size > KMALLOC_MAX_SIZE || !vc->vc_screenbuf_size)
1094		goto err_free;
1095	err = -ENOMEM;
1096	vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
1097	if (!vc->vc_screenbuf)
1098		goto err_free;
1099
1100	/* If no drivers have overridden us and the user didn't pass a
1101	   boot option, default to displaying the cursor */
1102	if (global_cursor_default == -1)
1103		global_cursor_default = 1;
1104
1105	vc_init(vc, 1);
1106	vcs_make_sysfs(currcons);
1107	atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, &param);
1108
1109	return 0;
1110err_free:
1111	visual_deinit(vc);
1112	kfree(vc);
1113	vc_cons[currcons].d = NULL;
1114	return err;
1115}
1116
1117static inline int resize_screen(struct vc_data *vc, int width, int height,
1118				int user)
1119{
1120	/* Resizes the resolution of the display adapater */
1121	int err = 0;
1122
1123	if (vc->vc_sw->con_resize)
1124		err = vc->vc_sw->con_resize(vc, width, height, user);
1125
1126	return err;
1127}
1128
1129/**
1130 *	vc_do_resize	-	resizing method for the tty
1131 *	@tty: tty being resized
1132 *	@vc: virtual console private data
1133 *	@cols: columns
1134 *	@lines: lines
1135 *
1136 *	Resize a virtual console, clipping according to the actual constraints.
1137 *	If the caller passes a tty structure then update the termios winsize
1138 *	information and perform any necessary signal handling.
1139 *
1140 *	Caller must hold the console semaphore. Takes the termios rwsem and
1141 *	ctrl.lock of the tty IFF a tty is passed.
1142 */
1143
1144static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
1145				unsigned int cols, unsigned int lines)
1146{
1147	unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
1148	unsigned long end;
1149	unsigned int old_rows, old_row_size, first_copied_row;
1150	unsigned int new_cols, new_rows, new_row_size, new_screen_size;
1151	unsigned int user;
1152	unsigned short *oldscreen, *newscreen;
1153	u32 **new_uniscr = NULL;
1154
1155	WARN_CONSOLE_UNLOCKED();
1156
1157	if (!vc)
1158		return -ENXIO;
1159
1160	user = vc->vc_resize_user;
1161	vc->vc_resize_user = 0;
1162
1163	if (cols > VC_MAXCOL || lines > VC_MAXROW)
1164		return -EINVAL;
1165
1166	new_cols = (cols ? cols : vc->vc_cols);
1167	new_rows = (lines ? lines : vc->vc_rows);
1168	new_row_size = new_cols << 1;
1169	new_screen_size = new_row_size * new_rows;
1170
1171	if (new_cols == vc->vc_cols && new_rows == vc->vc_rows) {
1172		/*
1173		 * This function is being called here to cover the case
1174		 * where the userspace calls the FBIOPUT_VSCREENINFO twice,
1175		 * passing the same fb_var_screeninfo containing the fields
1176		 * yres/xres equal to a number non-multiple of vc_font.height
1177		 * and yres_virtual/xres_virtual equal to number lesser than the
1178		 * vc_font.height and yres/xres.
1179		 * In the second call, the struct fb_var_screeninfo isn't
1180		 * being modified by the underlying driver because of the
1181		 * if above, and this causes the fbcon_display->vrows to become
1182		 * negative and it eventually leads to out-of-bound
1183		 * access by the imageblit function.
1184		 * To give the correct values to the struct and to not have
1185		 * to deal with possible errors from the code below, we call
1186		 * the resize_screen here as well.
1187		 */
1188		return resize_screen(vc, new_cols, new_rows, user);
1189	}
1190
1191	if (new_screen_size > KMALLOC_MAX_SIZE || !new_screen_size)
1192		return -EINVAL;
1193	newscreen = kzalloc(new_screen_size, GFP_USER);
1194	if (!newscreen)
1195		return -ENOMEM;
1196
1197	if (vc->vc_uni_lines) {
1198		new_uniscr = vc_uniscr_alloc(new_cols, new_rows);
1199		if (!new_uniscr) {
1200			kfree(newscreen);
1201			return -ENOMEM;
1202		}
1203	}
1204
1205	if (vc_is_sel(vc))
1206		clear_selection();
1207
1208	old_rows = vc->vc_rows;
1209	old_row_size = vc->vc_size_row;
1210
1211	err = resize_screen(vc, new_cols, new_rows, user);
1212	if (err) {
1213		kfree(newscreen);
1214		vc_uniscr_free(new_uniscr);
1215		return err;
1216	}
1217
1218	vc->vc_rows = new_rows;
1219	vc->vc_cols = new_cols;
1220	vc->vc_size_row = new_row_size;
1221	vc->vc_screenbuf_size = new_screen_size;
1222
1223	rlth = min(old_row_size, new_row_size);
1224	rrem = new_row_size - rlth;
1225	old_origin = vc->vc_origin;
1226	new_origin = (long) newscreen;
1227	new_scr_end = new_origin + new_screen_size;
1228
1229	if (vc->state.y > new_rows) {
1230		if (old_rows - vc->state.y < new_rows) {
1231			/*
1232			 * Cursor near the bottom, copy contents from the
1233			 * bottom of buffer
1234			 */
1235			first_copied_row = (old_rows - new_rows);
1236		} else {
1237			/*
1238			 * Cursor is in no man's land, copy 1/2 screenful
1239			 * from the top and bottom of cursor position
1240			 */
1241			first_copied_row = (vc->state.y - new_rows/2);
1242		}
1243		old_origin += first_copied_row * old_row_size;
1244	} else
1245		first_copied_row = 0;
1246	end = old_origin + old_row_size * min(old_rows, new_rows);
1247
1248	vc_uniscr_copy_area(new_uniscr, new_cols, new_rows,
1249			    vc->vc_uni_lines, rlth/2, first_copied_row,
1250			    min(old_rows, new_rows));
1251	vc_uniscr_set(vc, new_uniscr);
1252
1253	update_attr(vc);
1254
1255	while (old_origin < end) {
1256		scr_memcpyw((unsigned short *) new_origin,
1257			    (unsigned short *) old_origin, rlth);
1258		if (rrem)
1259			scr_memsetw((void *)(new_origin + rlth),
1260				    vc->vc_video_erase_char, rrem);
1261		old_origin += old_row_size;
1262		new_origin += new_row_size;
1263	}
1264	if (new_scr_end > new_origin)
1265		scr_memsetw((void *)new_origin, vc->vc_video_erase_char,
1266			    new_scr_end - new_origin);
1267	oldscreen = vc->vc_screenbuf;
1268	vc->vc_screenbuf = newscreen;
1269	vc->vc_screenbuf_size = new_screen_size;
1270	set_origin(vc);
1271	kfree(oldscreen);
1272
1273	/* do part of a reset_terminal() */
1274	vc->vc_top = 0;
1275	vc->vc_bottom = vc->vc_rows;
1276	gotoxy(vc, vc->state.x, vc->state.y);
1277	save_cur(vc);
1278
1279	if (tty) {
1280		/* Rewrite the requested winsize data with the actual
1281		   resulting sizes */
1282		struct winsize ws;
1283		memset(&ws, 0, sizeof(ws));
1284		ws.ws_row = vc->vc_rows;
1285		ws.ws_col = vc->vc_cols;
1286		ws.ws_ypixel = vc->vc_scan_lines;
1287		tty_do_resize(tty, &ws);
1288	}
1289
1290	if (con_is_visible(vc))
1291		update_screen(vc);
1292	vt_event_post(VT_EVENT_RESIZE, vc->vc_num, vc->vc_num);
1293	notify_update(vc);
1294	return err;
1295}
1296
1297/**
1298 *	vc_resize		-	resize a VT
1299 *	@vc: virtual console
1300 *	@cols: columns
1301 *	@rows: rows
1302 *
1303 *	Resize a virtual console as seen from the console end of things. We
1304 *	use the common vc_do_resize methods to update the structures. The
1305 *	caller must hold the console sem to protect console internals and
1306 *	vc->port.tty
1307 */
1308
1309int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
1310{
1311	return vc_do_resize(vc->port.tty, vc, cols, rows);
1312}
1313EXPORT_SYMBOL(vc_resize);
1314
1315/**
1316 *	vt_resize		-	resize a VT
1317 *	@tty: tty to resize
1318 *	@ws: winsize attributes
1319 *
1320 *	Resize a virtual terminal. This is called by the tty layer as we
1321 *	register our own handler for resizing. The mutual helper does all
1322 *	the actual work.
1323 *
1324 *	Takes the console sem and the called methods then take the tty
1325 *	termios_rwsem and the tty ctrl.lock in that order.
1326 */
1327static int vt_resize(struct tty_struct *tty, struct winsize *ws)
1328{
1329	struct vc_data *vc = tty->driver_data;
1330	int ret;
1331
1332	console_lock();
1333	ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row);
1334	console_unlock();
1335	return ret;
1336}
1337
1338struct vc_data *vc_deallocate(unsigned int currcons)
1339{
1340	struct vc_data *vc = NULL;
1341
1342	WARN_CONSOLE_UNLOCKED();
1343
1344	if (vc_cons_allocated(currcons)) {
1345		struct vt_notifier_param param;
1346
1347		param.vc = vc = vc_cons[currcons].d;
1348		atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, &param);
1349		vcs_remove_sysfs(currcons);
1350		visual_deinit(vc);
1351		con_free_unimap(vc);
1352		put_pid(vc->vt_pid);
1353		vc_uniscr_set(vc, NULL);
1354		kfree(vc->vc_screenbuf);
1355		vc_cons[currcons].d = NULL;
1356	}
1357	return vc;
1358}
1359
1360/*
1361 *	VT102 emulator
1362 */
1363
1364enum { EPecma = 0, EPdec, EPeq, EPgt, EPlt};
1365
1366#define set_kbd(vc, x)	vt_set_kbd_mode_bit((vc)->vc_num, (x))
1367#define clr_kbd(vc, x)	vt_clr_kbd_mode_bit((vc)->vc_num, (x))
1368#define is_kbd(vc, x)	vt_get_kbd_mode_bit((vc)->vc_num, (x))
1369
1370#define decarm		VC_REPEAT
1371#define decckm		VC_CKMODE
1372#define kbdapplic	VC_APPLIC
1373#define lnm		VC_CRLF
1374
1375const unsigned char color_table[] = { 0, 4, 2, 6, 1, 5, 3, 7,
1376				       8,12,10,14, 9,13,11,15 };
1377EXPORT_SYMBOL(color_table);
1378
1379/* the default colour table, for VGA+ colour systems */
1380unsigned char default_red[] = {
1381	0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa,
1382	0x55, 0xff, 0x55, 0xff, 0x55, 0xff, 0x55, 0xff
1383};
1384module_param_array(default_red, byte, NULL, S_IRUGO | S_IWUSR);
1385EXPORT_SYMBOL(default_red);
1386
1387unsigned char default_grn[] = {
1388	0x00, 0x00, 0xaa, 0x55, 0x00, 0x00, 0xaa, 0xaa,
1389	0x55, 0x55, 0xff, 0xff, 0x55, 0x55, 0xff, 0xff
1390};
1391module_param_array(default_grn, byte, NULL, S_IRUGO | S_IWUSR);
1392EXPORT_SYMBOL(default_grn);
1393
1394unsigned char default_blu[] = {
1395	0x00, 0x00, 0x00, 0x00, 0xaa, 0xaa, 0xaa, 0xaa,
1396	0x55, 0x55, 0x55, 0x55, 0xff, 0xff, 0xff, 0xff
1397};
1398module_param_array(default_blu, byte, NULL, S_IRUGO | S_IWUSR);
1399EXPORT_SYMBOL(default_blu);
1400
1401/*
1402 * gotoxy() must verify all boundaries, because the arguments
1403 * might also be negative. If the given position is out of
1404 * bounds, the cursor is placed at the nearest margin.
1405 */
1406static void gotoxy(struct vc_data *vc, int new_x, int new_y)
1407{
1408	int min_y, max_y;
1409
1410	if (new_x < 0)
1411		vc->state.x = 0;
1412	else {
1413		if (new_x >= vc->vc_cols)
1414			vc->state.x = vc->vc_cols - 1;
1415		else
1416			vc->state.x = new_x;
1417	}
1418
1419 	if (vc->vc_decom) {
1420		min_y = vc->vc_top;
1421		max_y = vc->vc_bottom;
1422	} else {
1423		min_y = 0;
1424		max_y = vc->vc_rows;
1425	}
1426	if (new_y < min_y)
1427		vc->state.y = min_y;
1428	else if (new_y >= max_y)
1429		vc->state.y = max_y - 1;
1430	else
1431		vc->state.y = new_y;
1432	vc->vc_pos = vc->vc_origin + vc->state.y * vc->vc_size_row +
1433		(vc->state.x << 1);
1434	vc->vc_need_wrap = 0;
1435}
1436
1437/* for absolute user moves, when decom is set */
1438static void gotoxay(struct vc_data *vc, int new_x, int new_y)
1439{
1440	gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y);
1441}
1442
1443void scrollback(struct vc_data *vc)
1444{
1445	scrolldelta(-(vc->vc_rows / 2));
1446}
1447
1448void scrollfront(struct vc_data *vc, int lines)
1449{
1450	if (!lines)
1451		lines = vc->vc_rows / 2;
1452	scrolldelta(lines);
1453}
1454
1455static void lf(struct vc_data *vc)
1456{
1457    	/* don't scroll if above bottom of scrolling region, or
1458	 * if below scrolling region
1459	 */
1460	if (vc->state.y + 1 == vc->vc_bottom)
1461		con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_UP, 1);
1462	else if (vc->state.y < vc->vc_rows - 1) {
1463		vc->state.y++;
1464		vc->vc_pos += vc->vc_size_row;
1465	}
1466	vc->vc_need_wrap = 0;
1467	notify_write(vc, '\n');
1468}
1469
1470static void ri(struct vc_data *vc)
1471{
1472    	/* don't scroll if below top of scrolling region, or
1473	 * if above scrolling region
1474	 */
1475	if (vc->state.y == vc->vc_top)
1476		con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_DOWN, 1);
1477	else if (vc->state.y > 0) {
1478		vc->state.y--;
1479		vc->vc_pos -= vc->vc_size_row;
1480	}
1481	vc->vc_need_wrap = 0;
1482}
1483
1484static inline void cr(struct vc_data *vc)
1485{
1486	vc->vc_pos -= vc->state.x << 1;
1487	vc->vc_need_wrap = vc->state.x = 0;
1488	notify_write(vc, '\r');
1489}
1490
1491static inline void bs(struct vc_data *vc)
1492{
1493	if (vc->state.x) {
1494		vc->vc_pos -= 2;
1495		vc->state.x--;
1496		vc->vc_need_wrap = 0;
1497		notify_write(vc, '\b');
1498	}
1499}
1500
1501static inline void del(struct vc_data *vc)
1502{
1503	/* ignored */
1504}
1505
1506static void csi_J(struct vc_data *vc, int vpar)
1507{
1508	unsigned int count;
1509	unsigned short * start;
1510
1511	switch (vpar) {
1512		case 0:	/* erase from cursor to end of display */
1513			vc_uniscr_clear_line(vc, vc->state.x,
1514					     vc->vc_cols - vc->state.x);
1515			vc_uniscr_clear_lines(vc, vc->state.y + 1,
1516					      vc->vc_rows - vc->state.y - 1);
1517			count = (vc->vc_scr_end - vc->vc_pos) >> 1;
1518			start = (unsigned short *)vc->vc_pos;
1519			break;
1520		case 1:	/* erase from start to cursor */
1521			vc_uniscr_clear_line(vc, 0, vc->state.x + 1);
1522			vc_uniscr_clear_lines(vc, 0, vc->state.y);
1523			count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1;
1524			start = (unsigned short *)vc->vc_origin;
1525			break;
1526		case 3: /* include scrollback */
1527			flush_scrollback(vc);
1528			fallthrough;
1529		case 2: /* erase whole display */
1530			vc_uniscr_clear_lines(vc, 0, vc->vc_rows);
1531			count = vc->vc_cols * vc->vc_rows;
1532			start = (unsigned short *)vc->vc_origin;
1533			break;
1534		default:
1535			return;
1536	}
1537	scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1538	if (con_should_update(vc))
1539		do_update_region(vc, (unsigned long) start, count);
1540	vc->vc_need_wrap = 0;
1541}
1542
1543static void csi_K(struct vc_data *vc, int vpar)
1544{
1545	unsigned int count;
1546	unsigned short *start = (unsigned short *)vc->vc_pos;
1547	int offset;
1548
1549	switch (vpar) {
1550		case 0:	/* erase from cursor to end of line */
1551			offset = 0;
1552			count = vc->vc_cols - vc->state.x;
1553			break;
1554		case 1:	/* erase from start of line to cursor */
1555			offset = -vc->state.x;
1556			count = vc->state.x + 1;
1557			break;
1558		case 2: /* erase whole line */
1559			offset = -vc->state.x;
1560			count = vc->vc_cols;
1561			break;
1562		default:
1563			return;
1564	}
1565	vc_uniscr_clear_line(vc, vc->state.x + offset, count);
1566	scr_memsetw(start + offset, vc->vc_video_erase_char, 2 * count);
1567	vc->vc_need_wrap = 0;
1568	if (con_should_update(vc))
1569		do_update_region(vc, (unsigned long)(start + offset), count);
1570}
1571
1572/* erase the following vpar positions */
1573static void csi_X(struct vc_data *vc, unsigned int vpar)
1574{					  /* not vt100? */
1575	unsigned int count;
1576
1577	if (!vpar)
1578		vpar++;
1579
1580	count = min(vpar, vc->vc_cols - vc->state.x);
1581
1582	vc_uniscr_clear_line(vc, vc->state.x, count);
1583	scr_memsetw((unsigned short *)vc->vc_pos, vc->vc_video_erase_char, 2 * count);
1584	if (con_should_update(vc))
1585		vc->vc_sw->con_clear(vc, vc->state.y, vc->state.x, 1, count);
1586	vc->vc_need_wrap = 0;
1587}
1588
1589static void default_attr(struct vc_data *vc)
1590{
1591	vc->state.intensity = VCI_NORMAL;
1592	vc->state.italic = false;
1593	vc->state.underline = false;
1594	vc->state.reverse = false;
1595	vc->state.blink = false;
1596	vc->state.color = vc->vc_def_color;
1597}
1598
1599struct rgb { u8 r; u8 g; u8 b; };
1600
1601static void rgb_from_256(int i, struct rgb *c)
1602{
1603	if (i < 8) {            /* Standard colours. */
1604		c->r = i&1 ? 0xaa : 0x00;
1605		c->g = i&2 ? 0xaa : 0x00;
1606		c->b = i&4 ? 0xaa : 0x00;
1607	} else if (i < 16) {
1608		c->r = i&1 ? 0xff : 0x55;
1609		c->g = i&2 ? 0xff : 0x55;
1610		c->b = i&4 ? 0xff : 0x55;
1611	} else if (i < 232) {   /* 6x6x6 colour cube. */
1612		c->r = (i - 16) / 36 * 85 / 2;
1613		c->g = (i - 16) / 6 % 6 * 85 / 2;
1614		c->b = (i - 16) % 6 * 85 / 2;
1615	} else                  /* Grayscale ramp. */
1616		c->r = c->g = c->b = i * 10 - 2312;
1617}
1618
1619static void rgb_foreground(struct vc_data *vc, const struct rgb *c)
1620{
1621	u8 hue = 0, max = max3(c->r, c->g, c->b);
1622
1623	if (c->r > max / 2)
1624		hue |= 4;
1625	if (c->g > max / 2)
1626		hue |= 2;
1627	if (c->b > max / 2)
1628		hue |= 1;
1629
1630	if (hue == 7 && max <= 0x55) {
1631		hue = 0;
1632		vc->state.intensity = VCI_BOLD;
1633	} else if (max > 0xaa)
1634		vc->state.intensity = VCI_BOLD;
1635	else
1636		vc->state.intensity = VCI_NORMAL;
1637
1638	vc->state.color = (vc->state.color & 0xf0) | hue;
1639}
1640
1641static void rgb_background(struct vc_data *vc, const struct rgb *c)
1642{
1643	/* For backgrounds, err on the dark side. */
1644	vc->state.color = (vc->state.color & 0x0f)
1645		| (c->r&0x80) >> 1 | (c->g&0x80) >> 2 | (c->b&0x80) >> 3;
1646}
1647
1648/*
1649 * ITU T.416 Higher colour modes. They break the usual properties of SGR codes
1650 * and thus need to be detected and ignored by hand. That standard also
1651 * wants : rather than ; as separators but sequences containing : are currently
1652 * completely ignored by the parser.
1653 *
1654 * Subcommands 3 (CMY) and 4 (CMYK) are so insane there's no point in
1655 * supporting them.
1656 */
1657static int vc_t416_color(struct vc_data *vc, int i,
1658		void(*set_color)(struct vc_data *vc, const struct rgb *c))
1659{
1660	struct rgb c;
1661
1662	i++;
1663	if (i > vc->vc_npar)
1664		return i;
1665
1666	if (vc->vc_par[i] == 5 && i + 1 <= vc->vc_npar) {
1667		/* 256 colours */
1668		i++;
1669		rgb_from_256(vc->vc_par[i], &c);
1670	} else if (vc->vc_par[i] == 2 && i + 3 <= vc->vc_npar) {
1671		/* 24 bit */
1672		c.r = vc->vc_par[i + 1];
1673		c.g = vc->vc_par[i + 2];
1674		c.b = vc->vc_par[i + 3];
1675		i += 3;
1676	} else
1677		return i;
1678
1679	set_color(vc, &c);
1680
1681	return i;
1682}
1683
1684/* console_lock is held */
1685static void csi_m(struct vc_data *vc)
1686{
1687	int i;
1688
1689	for (i = 0; i <= vc->vc_npar; i++)
1690		switch (vc->vc_par[i]) {
1691		case 0:	/* all attributes off */
1692			default_attr(vc);
1693			break;
1694		case 1:
1695			vc->state.intensity = VCI_BOLD;
1696			break;
1697		case 2:
1698			vc->state.intensity = VCI_HALF_BRIGHT;
1699			break;
1700		case 3:
1701			vc->state.italic = true;
1702			break;
1703		case 21:
1704			/*
1705			 * No console drivers support double underline, so
1706			 * convert it to a single underline.
1707			 */
1708		case 4:
1709			vc->state.underline = true;
1710			break;
1711		case 5:
1712			vc->state.blink = true;
1713			break;
1714		case 7:
1715			vc->state.reverse = true;
1716			break;
1717		case 10: /* ANSI X3.64-1979 (SCO-ish?)
1718			  * Select primary font, don't display control chars if
1719			  * defined, don't set bit 8 on output.
1720			  */
1721			vc->vc_translate = set_translate(vc->state.Gx_charset[vc->state.charset], vc);
1722			vc->vc_disp_ctrl = 0;
1723			vc->vc_toggle_meta = 0;
1724			break;
1725		case 11: /* ANSI X3.64-1979 (SCO-ish?)
1726			  * Select first alternate font, lets chars < 32 be
1727			  * displayed as ROM chars.
1728			  */
1729			vc->vc_translate = set_translate(IBMPC_MAP, vc);
1730			vc->vc_disp_ctrl = 1;
1731			vc->vc_toggle_meta = 0;
1732			break;
1733		case 12: /* ANSI X3.64-1979 (SCO-ish?)
1734			  * Select second alternate font, toggle high bit
1735			  * before displaying as ROM char.
1736			  */
1737			vc->vc_translate = set_translate(IBMPC_MAP, vc);
1738			vc->vc_disp_ctrl = 1;
1739			vc->vc_toggle_meta = 1;
1740			break;
1741		case 22:
1742			vc->state.intensity = VCI_NORMAL;
1743			break;
1744		case 23:
1745			vc->state.italic = false;
1746			break;
1747		case 24:
1748			vc->state.underline = false;
1749			break;
1750		case 25:
1751			vc->state.blink = false;
1752			break;
1753		case 27:
1754			vc->state.reverse = false;
1755			break;
1756		case 38:
1757			i = vc_t416_color(vc, i, rgb_foreground);
1758			break;
1759		case 48:
1760			i = vc_t416_color(vc, i, rgb_background);
1761			break;
1762		case 39:
1763			vc->state.color = (vc->vc_def_color & 0x0f) |
1764				(vc->state.color & 0xf0);
1765			break;
1766		case 49:
1767			vc->state.color = (vc->vc_def_color & 0xf0) |
1768				(vc->state.color & 0x0f);
1769			break;
1770		default:
1771			if (vc->vc_par[i] >= 90 && vc->vc_par[i] <= 107) {
1772				if (vc->vc_par[i] < 100)
1773					vc->state.intensity = VCI_BOLD;
1774				vc->vc_par[i] -= 60;
1775			}
1776			if (vc->vc_par[i] >= 30 && vc->vc_par[i] <= 37)
1777				vc->state.color = color_table[vc->vc_par[i] - 30]
1778					| (vc->state.color & 0xf0);
1779			else if (vc->vc_par[i] >= 40 && vc->vc_par[i] <= 47)
1780				vc->state.color = (color_table[vc->vc_par[i] - 40] << 4)
1781					| (vc->state.color & 0x0f);
1782			break;
1783		}
1784	update_attr(vc);
1785}
1786
1787static void respond_string(const char *p, size_t len, struct tty_port *port)
1788{
1789	tty_insert_flip_string(port, p, len);
1790	tty_flip_buffer_push(port);
1791}
1792
1793static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
1794{
1795	char buf[40];
1796	int len;
1797
1798	len = sprintf(buf, "\033[%d;%dR", vc->state.y +
1799			(vc->vc_decom ? vc->vc_top + 1 : 1),
1800			vc->state.x + 1);
1801	respond_string(buf, len, tty->port);
1802}
1803
1804static inline void status_report(struct tty_struct *tty)
1805{
1806	static const char teminal_ok[] = "\033[0n";
1807
1808	respond_string(teminal_ok, strlen(teminal_ok), tty->port);
1809}
1810
1811static inline void respond_ID(struct tty_struct *tty)
1812{
1813	/* terminal answer to an ESC-Z or csi0c query. */
1814	static const char vt102_id[] = "\033[?6c";
1815
1816	respond_string(vt102_id, strlen(vt102_id), tty->port);
1817}
1818
1819void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
1820{
1821	char buf[8];
1822	int len;
1823
1824	len = sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt),
1825			(char)('!' + mrx), (char)('!' + mry));
1826	respond_string(buf, len, tty->port);
1827}
1828
1829/* invoked via ioctl(TIOCLINUX) and through set_selection_user */
1830int mouse_reporting(void)
1831{
1832	return vc_cons[fg_console].d->vc_report_mouse;
1833}
1834
1835/* console_lock is held */
1836static void set_mode(struct vc_data *vc, int on_off)
1837{
1838	int i;
1839
1840	for (i = 0; i <= vc->vc_npar; i++)
1841		if (vc->vc_priv == EPdec) {
1842			switch(vc->vc_par[i]) {	/* DEC private modes set/reset */
1843			case 1:			/* Cursor keys send ^[Ox/^[[x */
1844				if (on_off)
1845					set_kbd(vc, decckm);
1846				else
1847					clr_kbd(vc, decckm);
1848				break;
1849			case 3:	/* 80/132 mode switch unimplemented */
1850#if 0
1851				vc_resize(deccolm ? 132 : 80, vc->vc_rows);
1852				/* this alone does not suffice; some user mode
1853				   utility has to change the hardware regs */
1854#endif
1855				break;
1856			case 5:			/* Inverted screen on/off */
1857				if (vc->vc_decscnm != on_off) {
1858					vc->vc_decscnm = on_off;
1859					invert_screen(vc, 0,
1860							vc->vc_screenbuf_size,
1861							false);
1862					update_attr(vc);
1863				}
1864				break;
1865			case 6:			/* Origin relative/absolute */
1866				vc->vc_decom = on_off;
1867				gotoxay(vc, 0, 0);
1868				break;
1869			case 7:			/* Autowrap on/off */
1870				vc->vc_decawm = on_off;
1871				break;
1872			case 8:			/* Autorepeat on/off */
1873				if (on_off)
1874					set_kbd(vc, decarm);
1875				else
1876					clr_kbd(vc, decarm);
1877				break;
1878			case 9:
1879				vc->vc_report_mouse = on_off ? 1 : 0;
1880				break;
1881			case 25:		/* Cursor on/off */
1882				vc->vc_deccm = on_off;
1883				break;
1884			case 1000:
1885				vc->vc_report_mouse = on_off ? 2 : 0;
1886				break;
1887			}
1888		} else {
1889			switch(vc->vc_par[i]) {	/* ANSI modes set/reset */
1890			case 3:			/* Monitor (display ctrls) */
1891				vc->vc_disp_ctrl = on_off;
1892				break;
1893			case 4:			/* Insert Mode on/off */
1894				vc->vc_decim = on_off;
1895				break;
1896			case 20:		/* Lf, Enter == CrLf/Lf */
1897				if (on_off)
1898					set_kbd(vc, lnm);
1899				else
1900					clr_kbd(vc, lnm);
1901				break;
1902			}
1903		}
1904}
1905
1906/* console_lock is held */
1907static void setterm_command(struct vc_data *vc)
1908{
1909	switch (vc->vc_par[0]) {
1910	case 1:	/* set color for underline mode */
1911		if (vc->vc_can_do_color && vc->vc_par[1] < 16) {
1912			vc->vc_ulcolor = color_table[vc->vc_par[1]];
1913			if (vc->state.underline)
1914				update_attr(vc);
1915		}
1916		break;
1917	case 2:	/* set color for half intensity mode */
1918		if (vc->vc_can_do_color && vc->vc_par[1] < 16) {
1919			vc->vc_halfcolor = color_table[vc->vc_par[1]];
1920			if (vc->state.intensity == VCI_HALF_BRIGHT)
1921				update_attr(vc);
1922		}
1923		break;
1924	case 8:	/* store colors as defaults */
1925		vc->vc_def_color = vc->vc_attr;
1926		if (vc->vc_hi_font_mask == 0x100)
1927			vc->vc_def_color >>= 1;
1928		default_attr(vc);
1929		update_attr(vc);
1930		break;
1931	case 9:	/* set blanking interval */
1932		blankinterval = min(vc->vc_par[1], 60U) * 60;
1933		poke_blanked_console();
1934		break;
1935	case 10: /* set bell frequency in Hz */
1936		if (vc->vc_npar >= 1)
1937			vc->vc_bell_pitch = vc->vc_par[1];
1938		else
1939			vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
1940		break;
1941	case 11: /* set bell duration in msec */
1942		if (vc->vc_npar >= 1)
1943			vc->vc_bell_duration = (vc->vc_par[1] < 2000) ?
1944				msecs_to_jiffies(vc->vc_par[1]) : 0;
1945		else
1946			vc->vc_bell_duration = DEFAULT_BELL_DURATION;
1947		break;
1948	case 12: /* bring specified console to the front */
1949		if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1))
1950			set_console(vc->vc_par[1] - 1);
1951		break;
1952	case 13: /* unblank the screen */
1953		poke_blanked_console();
1954		break;
1955	case 14: /* set vesa powerdown interval */
1956		vesa_off_interval = min(vc->vc_par[1], 60U) * 60 * HZ;
1957		break;
1958	case 15: /* activate the previous console */
1959		set_console(last_console);
1960		break;
1961	case 16: /* set cursor blink duration in msec */
1962		if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 &&
1963				vc->vc_par[1] <= USHRT_MAX)
1964			vc->vc_cur_blink_ms = vc->vc_par[1];
1965		else
1966			vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1967		break;
1968	}
1969}
1970
1971/* console_lock is held */
1972static void csi_at(struct vc_data *vc, unsigned int nr)
1973{
1974	if (nr > vc->vc_cols - vc->state.x)
1975		nr = vc->vc_cols - vc->state.x;
1976	else if (!nr)
1977		nr = 1;
1978	insert_char(vc, nr);
1979}
1980
1981/* console_lock is held */
1982static void csi_L(struct vc_data *vc, unsigned int nr)
1983{
1984	if (nr > vc->vc_rows - vc->state.y)
1985		nr = vc->vc_rows - vc->state.y;
1986	else if (!nr)
1987		nr = 1;
1988	con_scroll(vc, vc->state.y, vc->vc_bottom, SM_DOWN, nr);
1989	vc->vc_need_wrap = 0;
1990}
1991
1992/* console_lock is held */
1993static void csi_P(struct vc_data *vc, unsigned int nr)
1994{
1995	if (nr > vc->vc_cols - vc->state.x)
1996		nr = vc->vc_cols - vc->state.x;
1997	else if (!nr)
1998		nr = 1;
1999	delete_char(vc, nr);
2000}
2001
2002/* console_lock is held */
2003static void csi_M(struct vc_data *vc, unsigned int nr)
2004{
2005	if (nr > vc->vc_rows - vc->state.y)
2006		nr = vc->vc_rows - vc->state.y;
2007	else if (!nr)
2008		nr=1;
2009	con_scroll(vc, vc->state.y, vc->vc_bottom, SM_UP, nr);
2010	vc->vc_need_wrap = 0;
2011}
2012
2013/* console_lock is held (except via vc_init->reset_terminal */
2014static void save_cur(struct vc_data *vc)
2015{
2016	memcpy(&vc->saved_state, &vc->state, sizeof(vc->state));
2017}
2018
2019/* console_lock is held */
2020static void restore_cur(struct vc_data *vc)
2021{
2022	memcpy(&vc->state, &vc->saved_state, sizeof(vc->state));
2023
2024	gotoxy(vc, vc->state.x, vc->state.y);
2025	vc->vc_translate = set_translate(vc->state.Gx_charset[vc->state.charset],
2026			vc);
2027	update_attr(vc);
2028	vc->vc_need_wrap = 0;
2029}
2030
2031enum { ESnormal, ESesc, ESsquare, ESgetpars, ESfunckey,
2032	EShash, ESsetG0, ESsetG1, ESpercent, EScsiignore, ESnonstd,
2033	ESpalette, ESosc, ESapc, ESpm, ESdcs };
2034
2035/* console_lock is held (except via vc_init()) */
2036static void reset_terminal(struct vc_data *vc, int do_clear)
2037{
2038	unsigned int i;
2039
2040	vc->vc_top		= 0;
2041	vc->vc_bottom		= vc->vc_rows;
2042	vc->vc_state		= ESnormal;
2043	vc->vc_priv		= EPecma;
2044	vc->vc_translate	= set_translate(LAT1_MAP, vc);
2045	vc->state.Gx_charset[0]	= LAT1_MAP;
2046	vc->state.Gx_charset[1]	= GRAF_MAP;
2047	vc->state.charset	= 0;
2048	vc->vc_need_wrap	= 0;
2049	vc->vc_report_mouse	= 0;
2050	vc->vc_utf              = default_utf8;
2051	vc->vc_utf_count	= 0;
2052
2053	vc->vc_disp_ctrl	= 0;
2054	vc->vc_toggle_meta	= 0;
2055
2056	vc->vc_decscnm		= 0;
2057	vc->vc_decom		= 0;
2058	vc->vc_decawm		= 1;
2059	vc->vc_deccm		= global_cursor_default;
2060	vc->vc_decim		= 0;
2061
2062	vt_reset_keyboard(vc->vc_num);
2063
2064	vc->vc_cursor_type = cur_default;
2065	vc->vc_complement_mask = vc->vc_s_complement_mask;
2066
2067	default_attr(vc);
2068	update_attr(vc);
2069
2070	bitmap_zero(vc->vc_tab_stop, VC_TABSTOPS_COUNT);
2071	for (i = 0; i < VC_TABSTOPS_COUNT; i += 8)
2072		set_bit(i, vc->vc_tab_stop);
2073
2074	vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
2075	vc->vc_bell_duration = DEFAULT_BELL_DURATION;
2076	vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
2077
2078	gotoxy(vc, 0, 0);
2079	save_cur(vc);
2080	if (do_clear)
2081	    csi_J(vc, 2);
2082}
2083
2084static void vc_setGx(struct vc_data *vc, unsigned int which, int c)
2085{
2086	unsigned char *charset = &vc->state.Gx_charset[which];
2087
2088	switch (c) {
2089	case '0':
2090		*charset = GRAF_MAP;
2091		break;
2092	case 'B':
2093		*charset = LAT1_MAP;
2094		break;
2095	case 'U':
2096		*charset = IBMPC_MAP;
2097		break;
2098	case 'K':
2099		*charset = USER_MAP;
2100		break;
2101	}
2102
2103	if (vc->state.charset == which)
2104		vc->vc_translate = set_translate(*charset, vc);
2105}
2106
2107/* is this state an ANSI control string? */
2108static bool ansi_control_string(unsigned int state)
2109{
2110	if (state == ESosc || state == ESapc || state == ESpm || state == ESdcs)
2111		return true;
2112	return false;
2113}
2114
2115/* console_lock is held */
2116static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
2117{
2118	/*
2119	 *  Control characters can be used in the _middle_
2120	 *  of an escape sequence, aside from ANSI control strings.
2121	 */
2122	if (ansi_control_string(vc->vc_state) && c >= 8 && c <= 13)
2123		return;
2124	switch (c) {
2125	case 0:
2126		return;
2127	case 7:
2128		if (ansi_control_string(vc->vc_state))
2129			vc->vc_state = ESnormal;
2130		else if (vc->vc_bell_duration)
2131			kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration);
2132		return;
2133	case 8:
2134		bs(vc);
2135		return;
2136	case 9:
2137		vc->vc_pos -= (vc->state.x << 1);
2138
2139		vc->state.x = find_next_bit(vc->vc_tab_stop,
2140				min(vc->vc_cols - 1, VC_TABSTOPS_COUNT),
2141				vc->state.x + 1);
2142		if (vc->state.x >= VC_TABSTOPS_COUNT)
2143			vc->state.x = vc->vc_cols - 1;
2144
2145		vc->vc_pos += (vc->state.x << 1);
2146		notify_write(vc, '\t');
2147		return;
2148	case 10: case 11: case 12:
2149		lf(vc);
2150		if (!is_kbd(vc, lnm))
2151			return;
2152		fallthrough;
2153	case 13:
2154		cr(vc);
2155		return;
2156	case 14:
2157		vc->state.charset = 1;
2158		vc->vc_translate = set_translate(vc->state.Gx_charset[1], vc);
2159		vc->vc_disp_ctrl = 1;
2160		return;
2161	case 15:
2162		vc->state.charset = 0;
2163		vc->vc_translate = set_translate(vc->state.Gx_charset[0], vc);
2164		vc->vc_disp_ctrl = 0;
2165		return;
2166	case 24: case 26:
2167		vc->vc_state = ESnormal;
2168		return;
2169	case 27:
2170		vc->vc_state = ESesc;
2171		return;
2172	case 127:
2173		del(vc);
2174		return;
2175	case 128+27:
2176		vc->vc_state = ESsquare;
2177		return;
2178	}
2179	switch(vc->vc_state) {
2180	case ESesc:
2181		vc->vc_state = ESnormal;
2182		switch (c) {
2183		case '[':
2184			vc->vc_state = ESsquare;
2185			return;
2186		case ']':
2187			vc->vc_state = ESnonstd;
2188			return;
2189		case '_':
2190			vc->vc_state = ESapc;
2191			return;
2192		case '^':
2193			vc->vc_state = ESpm;
2194			return;
2195		case '%':
2196			vc->vc_state = ESpercent;
2197			return;
2198		case 'E':
2199			cr(vc);
2200			lf(vc);
2201			return;
2202		case 'M':
2203			ri(vc);
2204			return;
2205		case 'D':
2206			lf(vc);
2207			return;
2208		case 'H':
2209			if (vc->state.x < VC_TABSTOPS_COUNT)
2210				set_bit(vc->state.x, vc->vc_tab_stop);
2211			return;
2212		case 'P':
2213			vc->vc_state = ESdcs;
2214			return;
2215		case 'Z':
2216			respond_ID(tty);
2217			return;
2218		case '7':
2219			save_cur(vc);
2220			return;
2221		case '8':
2222			restore_cur(vc);
2223			return;
2224		case '(':
2225			vc->vc_state = ESsetG0;
2226			return;
2227		case ')':
2228			vc->vc_state = ESsetG1;
2229			return;
2230		case '#':
2231			vc->vc_state = EShash;
2232			return;
2233		case 'c':
2234			reset_terminal(vc, 1);
2235			return;
2236		case '>':  /* Numeric keypad */
2237			clr_kbd(vc, kbdapplic);
2238			return;
2239		case '=':  /* Appl. keypad */
2240			set_kbd(vc, kbdapplic);
2241			return;
2242		}
2243		return;
2244	case ESnonstd:
2245		if (c=='P') {   /* palette escape sequence */
2246			for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2247				vc->vc_par[vc->vc_npar] = 0;
2248			vc->vc_npar = 0;
2249			vc->vc_state = ESpalette;
2250			return;
2251		} else if (c=='R') {   /* reset palette */
2252			reset_palette(vc);
2253			vc->vc_state = ESnormal;
2254		} else if (c>='0' && c<='9')
2255			vc->vc_state = ESosc;
2256		else
2257			vc->vc_state = ESnormal;
2258		return;
2259	case ESpalette:
2260		if (isxdigit(c)) {
2261			vc->vc_par[vc->vc_npar++] = hex_to_bin(c);
2262			if (vc->vc_npar == 7) {
2263				int i = vc->vc_par[0] * 3, j = 1;
2264				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2265				vc->vc_palette[i++] += vc->vc_par[j++];
2266				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2267				vc->vc_palette[i++] += vc->vc_par[j++];
2268				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2269				vc->vc_palette[i] += vc->vc_par[j];
2270				set_palette(vc);
2271				vc->vc_state = ESnormal;
2272			}
2273		} else
2274			vc->vc_state = ESnormal;
2275		return;
2276	case ESsquare:
2277		for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2278			vc->vc_par[vc->vc_npar] = 0;
2279		vc->vc_npar = 0;
2280		vc->vc_state = ESgetpars;
2281		if (c == '[') { /* Function key */
2282			vc->vc_state=ESfunckey;
2283			return;
2284		}
2285		switch (c) {
2286		case '?':
2287			vc->vc_priv = EPdec;
2288			return;
2289		case '>':
2290			vc->vc_priv = EPgt;
2291			return;
2292		case '=':
2293			vc->vc_priv = EPeq;
2294			return;
2295		case '<':
2296			vc->vc_priv = EPlt;
2297			return;
2298		}
2299		vc->vc_priv = EPecma;
2300		fallthrough;
2301	case ESgetpars:
2302		if (c == ';' && vc->vc_npar < NPAR - 1) {
2303			vc->vc_npar++;
2304			return;
2305		} else if (c>='0' && c<='9') {
2306			vc->vc_par[vc->vc_npar] *= 10;
2307			vc->vc_par[vc->vc_npar] += c - '0';
2308			return;
2309		}
2310		if (c >= 0x20 && c <= 0x3f) { /* 0x2x, 0x3a and 0x3c - 0x3f */
2311			vc->vc_state = EScsiignore;
2312			return;
2313		}
2314		vc->vc_state = ESnormal;
2315		switch(c) {
2316		case 'h':
2317			if (vc->vc_priv <= EPdec)
2318				set_mode(vc, 1);
2319			return;
2320		case 'l':
2321			if (vc->vc_priv <= EPdec)
2322				set_mode(vc, 0);
2323			return;
2324		case 'c':
2325			if (vc->vc_priv == EPdec) {
2326				if (vc->vc_par[0])
2327					vc->vc_cursor_type =
2328						CUR_MAKE(vc->vc_par[0],
2329							 vc->vc_par[1],
2330							 vc->vc_par[2]);
2331				else
2332					vc->vc_cursor_type = cur_default;
2333				return;
2334			}
2335			break;
2336		case 'm':
2337			if (vc->vc_priv == EPdec) {
2338				clear_selection();
2339				if (vc->vc_par[0])
2340					vc->vc_complement_mask = vc->vc_par[0] << 8 | vc->vc_par[1];
2341				else
2342					vc->vc_complement_mask = vc->vc_s_complement_mask;
2343				return;
2344			}
2345			break;
2346		case 'n':
2347			if (vc->vc_priv == EPecma) {
2348				if (vc->vc_par[0] == 5)
2349					status_report(tty);
2350				else if (vc->vc_par[0] == 6)
2351					cursor_report(vc, tty);
2352			}
2353			return;
2354		}
2355		if (vc->vc_priv != EPecma) {
2356			vc->vc_priv = EPecma;
2357			return;
2358		}
2359		switch(c) {
2360		case 'G': case '`':
2361			if (vc->vc_par[0])
2362				vc->vc_par[0]--;
2363			gotoxy(vc, vc->vc_par[0], vc->state.y);
2364			return;
2365		case 'A':
2366			if (!vc->vc_par[0])
2367				vc->vc_par[0]++;
2368			gotoxy(vc, vc->state.x, vc->state.y - vc->vc_par[0]);
2369			return;
2370		case 'B': case 'e':
2371			if (!vc->vc_par[0])
2372				vc->vc_par[0]++;
2373			gotoxy(vc, vc->state.x, vc->state.y + vc->vc_par[0]);
2374			return;
2375		case 'C': case 'a':
2376			if (!vc->vc_par[0])
2377				vc->vc_par[0]++;
2378			gotoxy(vc, vc->state.x + vc->vc_par[0], vc->state.y);
2379			return;
2380		case 'D':
2381			if (!vc->vc_par[0])
2382				vc->vc_par[0]++;
2383			gotoxy(vc, vc->state.x - vc->vc_par[0], vc->state.y);
2384			return;
2385		case 'E':
2386			if (!vc->vc_par[0])
2387				vc->vc_par[0]++;
2388			gotoxy(vc, 0, vc->state.y + vc->vc_par[0]);
2389			return;
2390		case 'F':
2391			if (!vc->vc_par[0])
2392				vc->vc_par[0]++;
2393			gotoxy(vc, 0, vc->state.y - vc->vc_par[0]);
2394			return;
2395		case 'd':
2396			if (vc->vc_par[0])
2397				vc->vc_par[0]--;
2398			gotoxay(vc, vc->state.x ,vc->vc_par[0]);
2399			return;
2400		case 'H': case 'f':
2401			if (vc->vc_par[0])
2402				vc->vc_par[0]--;
2403			if (vc->vc_par[1])
2404				vc->vc_par[1]--;
2405			gotoxay(vc, vc->vc_par[1], vc->vc_par[0]);
2406			return;
2407		case 'J':
2408			csi_J(vc, vc->vc_par[0]);
2409			return;
2410		case 'K':
2411			csi_K(vc, vc->vc_par[0]);
2412			return;
2413		case 'L':
2414			csi_L(vc, vc->vc_par[0]);
2415			return;
2416		case 'M':
2417			csi_M(vc, vc->vc_par[0]);
2418			return;
2419		case 'P':
2420			csi_P(vc, vc->vc_par[0]);
2421			return;
2422		case 'c':
2423			if (!vc->vc_par[0])
2424				respond_ID(tty);
2425			return;
2426		case 'g':
2427			if (!vc->vc_par[0] && vc->state.x < VC_TABSTOPS_COUNT)
2428				set_bit(vc->state.x, vc->vc_tab_stop);
2429			else if (vc->vc_par[0] == 3)
2430				bitmap_zero(vc->vc_tab_stop, VC_TABSTOPS_COUNT);
2431			return;
2432		case 'm':
2433			csi_m(vc);
2434			return;
2435		case 'q': /* DECLL - but only 3 leds */
2436			/* map 0,1,2,3 to 0,1,2,4 */
2437			if (vc->vc_par[0] < 4)
2438				vt_set_led_state(vc->vc_num,
2439					    (vc->vc_par[0] < 3) ? vc->vc_par[0] : 4);
2440			return;
2441		case 'r':
2442			if (!vc->vc_par[0])
2443				vc->vc_par[0]++;
2444			if (!vc->vc_par[1])
2445				vc->vc_par[1] = vc->vc_rows;
2446			/* Minimum allowed region is 2 lines */
2447			if (vc->vc_par[0] < vc->vc_par[1] &&
2448			    vc->vc_par[1] <= vc->vc_rows) {
2449				vc->vc_top = vc->vc_par[0] - 1;
2450				vc->vc_bottom = vc->vc_par[1];
2451				gotoxay(vc, 0, 0);
2452			}
2453			return;
2454		case 's':
2455			save_cur(vc);
2456			return;
2457		case 'u':
2458			restore_cur(vc);
2459			return;
2460		case 'X':
2461			csi_X(vc, vc->vc_par[0]);
2462			return;
2463		case '@':
2464			csi_at(vc, vc->vc_par[0]);
2465			return;
2466		case ']': /* setterm functions */
2467			setterm_command(vc);
2468			return;
2469		}
2470		return;
2471	case EScsiignore:
2472		if (c >= 0x20 && c <= 0x3f)
2473			return;
2474		vc->vc_state = ESnormal;
2475		return;
2476	case ESpercent:
2477		vc->vc_state = ESnormal;
2478		switch (c) {
2479		case '@':  /* defined in ISO 2022 */
2480			vc->vc_utf = 0;
2481			return;
2482		case 'G':  /* prelim official escape code */
2483		case '8':  /* retained for compatibility */
2484			vc->vc_utf = 1;
2485			return;
2486		}
2487		return;
2488	case ESfunckey:
2489		vc->vc_state = ESnormal;
2490		return;
2491	case EShash:
2492		vc->vc_state = ESnormal;
2493		if (c == '8') {
2494			/* DEC screen alignment test. kludge :-) */
2495			vc->vc_video_erase_char =
2496				(vc->vc_video_erase_char & 0xff00) | 'E';
2497			csi_J(vc, 2);
2498			vc->vc_video_erase_char =
2499				(vc->vc_video_erase_char & 0xff00) | ' ';
2500			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
2501		}
2502		return;
2503	case ESsetG0:
2504		vc_setGx(vc, 0, c);
2505		vc->vc_state = ESnormal;
2506		return;
2507	case ESsetG1:
2508		vc_setGx(vc, 1, c);
2509		vc->vc_state = ESnormal;
2510		return;
2511	case ESapc:
2512		return;
2513	case ESosc:
2514		return;
2515	case ESpm:
2516		return;
2517	case ESdcs:
2518		return;
2519	default:
2520		vc->vc_state = ESnormal;
2521	}
2522}
2523
2524/* is_double_width() is based on the wcwidth() implementation by
2525 * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
2526 * Latest version: https://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
2527 */
2528struct interval {
2529	uint32_t first;
2530	uint32_t last;
2531};
2532
2533static int ucs_cmp(const void *key, const void *elt)
2534{
2535	uint32_t ucs = *(uint32_t *)key;
2536	struct interval e = *(struct interval *) elt;
2537
2538	if (ucs > e.last)
2539		return 1;
2540	else if (ucs < e.first)
2541		return -1;
2542	return 0;
2543}
2544
2545static int is_double_width(uint32_t ucs)
2546{
2547	static const struct interval double_width[] = {
2548		{ 0x1100, 0x115F }, { 0x2329, 0x232A }, { 0x2E80, 0x303E },
2549		{ 0x3040, 0xA4CF }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF },
2550		{ 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 },
2551		{ 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }
2552	};
2553	if (ucs < double_width[0].first ||
2554	    ucs > double_width[ARRAY_SIZE(double_width) - 1].last)
2555		return 0;
2556
2557	return bsearch(&ucs, double_width, ARRAY_SIZE(double_width),
2558			sizeof(struct interval), ucs_cmp) != NULL;
2559}
2560
2561struct vc_draw_region {
2562	unsigned long from, to;
2563	int x;
2564};
2565
2566static void con_flush(struct vc_data *vc, struct vc_draw_region *draw)
2567{
2568	if (draw->x < 0)
2569		return;
2570
2571	vc->vc_sw->con_putcs(vc, (u16 *)draw->from,
2572			(u16 *)draw->to - (u16 *)draw->from, vc->state.y,
2573			draw->x);
2574	draw->x = -1;
2575}
2576
2577static inline int vc_translate_ascii(const struct vc_data *vc, int c)
2578{
2579	if (IS_ENABLED(CONFIG_CONSOLE_TRANSLATIONS)) {
2580		if (vc->vc_toggle_meta)
2581			c |= 0x80;
2582
2583		return vc->vc_translate[c];
2584	}
2585
2586	return c;
2587}
2588
2589
2590/**
2591 * vc_sanitize_unicode -- Replace invalid Unicode code points with U+FFFD
2592 * @c: the received character, or U+FFFD for invalid sequences.
2593 */
2594static inline int vc_sanitize_unicode(const int c)
2595{
2596	if ((c >= 0xd800 && c <= 0xdfff) || c == 0xfffe || c == 0xffff)
2597		return 0xfffd;
2598
2599	return c;
2600}
2601
2602/**
2603 * vc_translate_unicode -- Combine UTF-8 into Unicode in @vc_utf_char
2604 * @vc: virtual console
2605 * @c: character to translate
2606 * @rescan: we return true if we need more (continuation) data
2607 *
2608 * @vc_utf_char is the being-constructed unicode character.
2609 * @vc_utf_count is the number of continuation bytes still expected to arrive.
2610 * @vc_npar is the number of continuation bytes arrived so far.
2611 */
2612static int vc_translate_unicode(struct vc_data *vc, int c, bool *rescan)
2613{
2614	static const u32 utf8_length_changes[] = {
2615		0x0000007f, 0x000007ff, 0x0000ffff,
2616		0x001fffff, 0x03ffffff, 0x7fffffff
2617	};
2618
2619	/* Continuation byte received */
2620	if ((c & 0xc0) == 0x80) {
2621		/* Unexpected continuation byte? */
2622		if (!vc->vc_utf_count)
2623			return 0xfffd;
2624
2625		vc->vc_utf_char = (vc->vc_utf_char << 6) | (c & 0x3f);
2626		vc->vc_npar++;
2627		if (--vc->vc_utf_count)
2628			goto need_more_bytes;
2629
2630		/* Got a whole character */
2631		c = vc->vc_utf_char;
2632		/* Reject overlong sequences */
2633		if (c <= utf8_length_changes[vc->vc_npar - 1] ||
2634				c > utf8_length_changes[vc->vc_npar])
2635			return 0xfffd;
2636
2637		return vc_sanitize_unicode(c);
2638	}
2639
2640	/* Single ASCII byte or first byte of a sequence received */
2641	if (vc->vc_utf_count) {
2642		/* Continuation byte expected */
2643		*rescan = true;
2644		vc->vc_utf_count = 0;
2645		return 0xfffd;
2646	}
2647
2648	/* Nothing to do if an ASCII byte was received */
2649	if (c <= 0x7f)
2650		return c;
2651
2652	/* First byte of a multibyte sequence received */
2653	vc->vc_npar = 0;
2654	if ((c & 0xe0) == 0xc0) {
2655		vc->vc_utf_count = 1;
2656		vc->vc_utf_char = (c & 0x1f);
2657	} else if ((c & 0xf0) == 0xe0) {
2658		vc->vc_utf_count = 2;
2659		vc->vc_utf_char = (c & 0x0f);
2660	} else if ((c & 0xf8) == 0xf0) {
2661		vc->vc_utf_count = 3;
2662		vc->vc_utf_char = (c & 0x07);
2663	} else if ((c & 0xfc) == 0xf8) {
2664		vc->vc_utf_count = 4;
2665		vc->vc_utf_char = (c & 0x03);
2666	} else if ((c & 0xfe) == 0xfc) {
2667		vc->vc_utf_count = 5;
2668		vc->vc_utf_char = (c & 0x01);
2669	} else {
2670		/* 254 and 255 are invalid */
2671		return 0xfffd;
2672	}
2673
2674need_more_bytes:
2675	return -1;
2676}
2677
2678static int vc_translate(struct vc_data *vc, int *c, bool *rescan)
2679{
2680	/* Do no translation at all in control states */
2681	if (vc->vc_state != ESnormal)
2682		return *c;
2683
2684	if (vc->vc_utf && !vc->vc_disp_ctrl)
2685		return *c = vc_translate_unicode(vc, *c, rescan);
2686
2687	/* no utf or alternate charset mode */
2688	return vc_translate_ascii(vc, *c);
2689}
2690
2691static inline unsigned char vc_invert_attr(const struct vc_data *vc)
2692{
2693	if (!vc->vc_can_do_color)
2694		return vc->vc_attr ^ 0x08;
2695
2696	if (vc->vc_hi_font_mask == 0x100)
2697		return   (vc->vc_attr & 0x11) |
2698			((vc->vc_attr & 0xe0) >> 4) |
2699			((vc->vc_attr & 0x0e) << 4);
2700
2701	return   (vc->vc_attr & 0x88) |
2702		((vc->vc_attr & 0x70) >> 4) |
2703		((vc->vc_attr & 0x07) << 4);
2704}
2705
2706static bool vc_is_control(struct vc_data *vc, int tc, int c)
2707{
2708	/*
2709	 * A bitmap for codes <32. A bit of 1 indicates that the code
2710	 * corresponding to that bit number invokes some special action (such
2711	 * as cursor movement) and should not be displayed as a glyph unless
2712	 * the disp_ctrl mode is explicitly enabled.
2713	 */
2714	static const u32 CTRL_ACTION = 0x0d00ff81;
2715	/* Cannot be overridden by disp_ctrl */
2716	static const u32 CTRL_ALWAYS = 0x0800f501;
2717
2718	if (vc->vc_state != ESnormal)
2719		return true;
2720
2721	if (!tc)
2722		return true;
2723
2724	/*
2725	 * If the original code was a control character we only allow a glyph
2726	 * to be displayed if the code is not normally used (such as for cursor
2727	 * movement) or if the disp_ctrl mode has been explicitly enabled.
2728	 * Certain characters (as given by the CTRL_ALWAYS bitmap) are always
2729	 * displayed as control characters, as the console would be pretty
2730	 * useless without them; to display an arbitrary font position use the
2731	 * direct-to-font zone in UTF-8 mode.
2732	 */
2733	if (c < 32) {
2734		if (vc->vc_disp_ctrl)
2735			return CTRL_ALWAYS & BIT(c);
2736		else
2737			return vc->vc_utf || (CTRL_ACTION & BIT(c));
2738	}
2739
2740	if (c == 127 && !vc->vc_disp_ctrl)
2741		return true;
2742
2743	if (c == 128 + 27)
2744		return true;
2745
2746	return false;
2747}
2748
2749static int vc_con_write_normal(struct vc_data *vc, int tc, int c,
2750		struct vc_draw_region *draw)
2751{
2752	int next_c;
2753	unsigned char vc_attr = vc->vc_attr;
2754	u16 himask = vc->vc_hi_font_mask, charmask = himask ? 0x1ff : 0xff;
2755	u8 width = 1;
2756	bool inverse = false;
2757
2758	if (vc->vc_utf && !vc->vc_disp_ctrl) {
2759		if (is_double_width(c))
2760			width = 2;
2761	}
2762
2763	/* Now try to find out how to display it */
2764	tc = conv_uni_to_pc(vc, tc);
2765	if (tc & ~charmask) {
2766		if (tc == -1 || tc == -2)
2767			return -1; /* nothing to display */
2768
2769		/* Glyph not found */
2770		if ((!vc->vc_utf || vc->vc_disp_ctrl || c < 128) &&
2771				!(c & ~charmask)) {
2772			/*
2773			 * In legacy mode use the glyph we get by a 1:1
2774			 * mapping.
2775			 * This would make absolutely no sense with Unicode in
2776			 * mind, but do this for ASCII characters since a font
2777			 * may lack Unicode mapping info and we don't want to
2778			 * end up with having question marks only.
2779			 */
2780			tc = c;
2781		} else {
2782			/*
2783			 * Display U+FFFD. If it's not found, display an inverse
2784			 * question mark.
2785			 */
2786			tc = conv_uni_to_pc(vc, 0xfffd);
2787			if (tc < 0) {
2788				inverse = true;
2789				tc = conv_uni_to_pc(vc, '?');
2790				if (tc < 0)
2791					tc = '?';
2792
2793				vc_attr = vc_invert_attr(vc);
2794				con_flush(vc, draw);
2795			}
2796		}
2797	}
2798
2799	next_c = c;
2800	while (1) {
2801		if (vc->vc_need_wrap || vc->vc_decim)
2802			con_flush(vc, draw);
2803		if (vc->vc_need_wrap) {
2804			cr(vc);
2805			lf(vc);
2806		}
2807		if (vc->vc_decim)
2808			insert_char(vc, 1);
2809		vc_uniscr_putc(vc, next_c);
2810
2811		if (himask)
2812			tc = ((tc & 0x100) ? himask : 0) |
2813			      (tc &  0xff);
2814		tc |= (vc_attr << 8) & ~himask;
2815
2816		scr_writew(tc, (u16 *)vc->vc_pos);
2817
2818		if (con_should_update(vc) && draw->x < 0) {
2819			draw->x = vc->state.x;
2820			draw->from = vc->vc_pos;
2821		}
2822		if (vc->state.x == vc->vc_cols - 1) {
2823			vc->vc_need_wrap = vc->vc_decawm;
2824			draw->to = vc->vc_pos + 2;
2825		} else {
2826			vc->state.x++;
2827			draw->to = (vc->vc_pos += 2);
2828		}
2829
2830		if (!--width)
2831			break;
2832
2833		/* A space is printed in the second column */
2834		tc = conv_uni_to_pc(vc, ' ');
2835		if (tc < 0)
2836			tc = ' ';
2837		next_c = ' ';
2838	}
2839	notify_write(vc, c);
2840
2841	if (inverse)
2842		con_flush(vc, draw);
2843
2844	return 0;
2845}
2846
2847/* acquires console_lock */
2848static int do_con_write(struct tty_struct *tty, const u8 *buf, int count)
2849{
2850	struct vc_draw_region draw = {
2851		.x = -1,
2852	};
2853	int c, tc, n = 0;
2854	unsigned int currcons;
2855	struct vc_data *vc;
2856	struct vt_notifier_param param;
2857	bool rescan;
2858
2859	if (in_interrupt())
2860		return count;
2861
2862	console_lock();
2863	vc = tty->driver_data;
2864	if (vc == NULL) {
2865		pr_err("vt: argh, driver_data is NULL !\n");
2866		console_unlock();
2867		return 0;
2868	}
2869
2870	currcons = vc->vc_num;
2871	if (!vc_cons_allocated(currcons)) {
2872		/* could this happen? */
2873		pr_warn_once("con_write: tty %d not allocated\n", currcons+1);
2874		console_unlock();
2875		return 0;
2876	}
2877
2878
2879	/* undraw cursor first */
2880	if (con_is_fg(vc))
2881		hide_cursor(vc);
2882
2883	param.vc = vc;
2884
2885	while (!tty->flow.stopped && count) {
2886		int orig = *buf;
2887		buf++;
2888		n++;
2889		count--;
2890rescan_last_byte:
2891		c = orig;
2892		rescan = false;
2893
2894		tc = vc_translate(vc, &c, &rescan);
2895		if (tc == -1)
2896			continue;
2897
2898		param.c = tc;
2899		if (atomic_notifier_call_chain(&vt_notifier_list, VT_PREWRITE,
2900					&param) == NOTIFY_STOP)
2901			continue;
2902
2903		if (vc_is_control(vc, tc, c)) {
2904			con_flush(vc, &draw);
2905			do_con_trol(tty, vc, orig);
2906			continue;
2907		}
2908
2909		if (vc_con_write_normal(vc, tc, c, &draw) < 0)
2910			continue;
2911
2912		if (rescan)
2913			goto rescan_last_byte;
2914	}
2915	con_flush(vc, &draw);
2916	console_conditional_schedule();
2917	notify_update(vc);
2918	console_unlock();
2919	return n;
2920}
2921
2922/*
2923 * This is the console switching callback.
2924 *
2925 * Doing console switching in a process context allows
2926 * us to do the switches asynchronously (needed when we want
2927 * to switch due to a keyboard interrupt).  Synchronization
2928 * with other console code and prevention of re-entrancy is
2929 * ensured with console_lock.
2930 */
2931static void console_callback(struct work_struct *ignored)
2932{
2933	console_lock();
2934
2935	if (want_console >= 0) {
2936		if (want_console != fg_console &&
2937		    vc_cons_allocated(want_console)) {
2938			hide_cursor(vc_cons[fg_console].d);
2939			change_console(vc_cons[want_console].d);
2940			/* we only changed when the console had already
2941			   been allocated - a new console is not created
2942			   in an interrupt routine */
2943		}
2944		want_console = -1;
2945	}
2946	if (do_poke_blanked_console) { /* do not unblank for a LED change */
2947		do_poke_blanked_console = 0;
2948		poke_blanked_console();
2949	}
2950	if (scrollback_delta) {
2951		struct vc_data *vc = vc_cons[fg_console].d;
2952		clear_selection();
2953		if (vc->vc_mode == KD_TEXT && vc->vc_sw->con_scrolldelta)
2954			vc->vc_sw->con_scrolldelta(vc, scrollback_delta);
2955		scrollback_delta = 0;
2956	}
2957	if (blank_timer_expired) {
2958		do_blank_screen(0);
2959		blank_timer_expired = 0;
2960	}
2961	notify_update(vc_cons[fg_console].d);
2962
2963	console_unlock();
2964}
2965
2966int set_console(int nr)
2967{
2968	struct vc_data *vc = vc_cons[fg_console].d;
2969
2970	if (!vc_cons_allocated(nr) || vt_dont_switch ||
2971		(vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) {
2972
2973		/*
2974		 * Console switch will fail in console_callback() or
2975		 * change_console() so there is no point scheduling
2976		 * the callback
2977		 *
2978		 * Existing set_console() users don't check the return
2979		 * value so this shouldn't break anything
2980		 */
2981		return -EINVAL;
2982	}
2983
2984	want_console = nr;
2985	schedule_console_callback();
2986
2987	return 0;
2988}
2989
2990struct tty_driver *console_driver;
2991
2992#ifdef CONFIG_VT_CONSOLE
2993
2994/**
2995 * vt_kmsg_redirect() - Sets/gets the kernel message console
2996 * @new:	The new virtual terminal number or -1 if the console should stay
2997 * 		unchanged
2998 *
2999 * By default, the kernel messages are always printed on the current virtual
3000 * console. However, the user may modify that default with the
3001 * TIOCL_SETKMSGREDIRECT ioctl call.
3002 *
3003 * This function sets the kernel message console to be @new. It returns the old
3004 * virtual console number. The virtual terminal number 0 (both as parameter and
3005 * return value) means no redirection (i.e. always printed on the currently
3006 * active console).
3007 *
3008 * The parameter -1 means that only the current console is returned, but the
3009 * value is not modified. You may use the macro vt_get_kmsg_redirect() in that
3010 * case to make the code more understandable.
3011 *
3012 * When the kernel is compiled without CONFIG_VT_CONSOLE, this function ignores
3013 * the parameter and always returns 0.
3014 */
3015int vt_kmsg_redirect(int new)
3016{
3017	static int kmsg_con;
3018
3019	if (new != -1)
3020		return xchg(&kmsg_con, new);
3021	else
3022		return kmsg_con;
3023}
3024
3025/*
3026 *	Console on virtual terminal
3027 *
3028 * The console must be locked when we get here.
3029 */
3030
3031static void vt_console_print(struct console *co, const char *b, unsigned count)
3032{
3033	struct vc_data *vc = vc_cons[fg_console].d;
3034	unsigned char c;
3035	static DEFINE_SPINLOCK(printing_lock);
3036	const ushort *start;
3037	ushort start_x, cnt;
3038	int kmsg_console;
3039
3040	WARN_CONSOLE_UNLOCKED();
3041
3042	/* this protects against concurrent oops only */
3043	if (!spin_trylock(&printing_lock))
3044		return;
3045
3046	kmsg_console = vt_get_kmsg_redirect();
3047	if (kmsg_console && vc_cons_allocated(kmsg_console - 1))
3048		vc = vc_cons[kmsg_console - 1].d;
3049
3050	if (!vc_cons_allocated(fg_console)) {
3051		/* impossible */
3052		/* printk("vt_console_print: tty %d not allocated ??\n", currcons+1); */
3053		goto quit;
3054	}
3055
3056	if (vc->vc_mode != KD_TEXT)
3057		goto quit;
3058
3059	/* undraw cursor first */
3060	if (con_is_fg(vc))
3061		hide_cursor(vc);
3062
3063	start = (ushort *)vc->vc_pos;
3064	start_x = vc->state.x;
3065	cnt = 0;
3066	while (count--) {
3067		c = *b++;
3068		if (c == 10 || c == 13 || c == 8 || vc->vc_need_wrap) {
3069			if (cnt && con_is_visible(vc))
3070				vc->vc_sw->con_putcs(vc, start, cnt, vc->state.y, start_x);
3071			cnt = 0;
3072			if (c == 8) {		/* backspace */
3073				bs(vc);
3074				start = (ushort *)vc->vc_pos;
3075				start_x = vc->state.x;
3076				continue;
3077			}
3078			if (c != 13)
3079				lf(vc);
3080			cr(vc);
3081			start = (ushort *)vc->vc_pos;
3082			start_x = vc->state.x;
3083			if (c == 10 || c == 13)
3084				continue;
3085		}
3086		vc_uniscr_putc(vc, c);
3087		scr_writew((vc->vc_attr << 8) + c, (unsigned short *)vc->vc_pos);
3088		notify_write(vc, c);
3089		cnt++;
3090		if (vc->state.x == vc->vc_cols - 1) {
3091			vc->vc_need_wrap = 1;
3092		} else {
3093			vc->vc_pos += 2;
3094			vc->state.x++;
3095		}
3096	}
3097	if (cnt && con_is_visible(vc))
3098		vc->vc_sw->con_putcs(vc, start, cnt, vc->state.y, start_x);
3099	set_cursor(vc);
3100	notify_update(vc);
3101
3102quit:
3103	spin_unlock(&printing_lock);
3104}
3105
3106static struct tty_driver *vt_console_device(struct console *c, int *index)
3107{
3108	*index = c->index ? c->index-1 : fg_console;
3109	return console_driver;
3110}
3111
3112static int vt_console_setup(struct console *co, char *options)
3113{
3114	return co->index >= MAX_NR_CONSOLES ? -EINVAL : 0;
3115}
3116
3117static struct console vt_console_driver = {
3118	.name		= "tty",
3119	.setup		= vt_console_setup,
3120	.write		= vt_console_print,
3121	.device		= vt_console_device,
3122	.unblank	= unblank_screen,
3123	.flags		= CON_PRINTBUFFER,
3124	.index		= -1,
3125};
3126#endif
3127
3128/*
3129 *	Handling of Linux-specific VC ioctls
3130 */
3131
3132/*
3133 * Generally a bit racy with respect to console_lock();.
3134 *
3135 * There are some functions which don't need it.
3136 *
3137 * There are some functions which can sleep for arbitrary periods
3138 * (paste_selection) but we don't need the lock there anyway.
3139 *
3140 * set_selection_user has locking, and definitely needs it
3141 */
3142
3143int tioclinux(struct tty_struct *tty, unsigned long arg)
3144{
3145	char type, data;
3146	char __user *p = (char __user *)arg;
3147	int lines;
3148	int ret;
3149
3150	if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
3151		return -EPERM;
3152	if (get_user(type, p))
3153		return -EFAULT;
3154	ret = 0;
3155
3156	switch (type) {
3157	case TIOCL_SETSEL:
3158		return set_selection_user((struct tiocl_selection
3159					 __user *)(p+1), tty);
3160	case TIOCL_PASTESEL:
3161		return paste_selection(tty);
3162	case TIOCL_UNBLANKSCREEN:
3163		console_lock();
3164		unblank_screen();
3165		console_unlock();
3166		break;
3167	case TIOCL_SELLOADLUT:
3168		console_lock();
3169		ret = sel_loadlut(p);
3170		console_unlock();
3171		break;
3172	case TIOCL_GETSHIFTSTATE:
3173		/*
3174		 * Make it possible to react to Shift+Mousebutton. Note that
3175		 * 'shift_state' is an undocumented kernel-internal variable;
3176		 * programs not closely related to the kernel should not use
3177		 * this.
3178		 */
3179		data = vt_get_shift_state();
3180		return put_user(data, p);
3181	case TIOCL_GETMOUSEREPORTING:
3182		console_lock();	/* May be overkill */
3183		data = mouse_reporting();
3184		console_unlock();
3185		return put_user(data, p);
3186	case TIOCL_SETVESABLANK:
3187		console_lock();
3188		ret = set_vesa_blanking(p);
3189		console_unlock();
3190		break;
3191	case TIOCL_GETKMSGREDIRECT:
3192		data = vt_get_kmsg_redirect();
3193		return put_user(data, p);
3194	case TIOCL_SETKMSGREDIRECT:
3195		if (!capable(CAP_SYS_ADMIN))
3196			return -EPERM;
3197
3198		if (get_user(data, p+1))
3199			return -EFAULT;
3200
3201		vt_kmsg_redirect(data);
3202
3203		break;
3204	case TIOCL_GETFGCONSOLE:
3205		/*
3206		 * No locking needed as this is a transiently correct return
3207		 * anyway if the caller hasn't disabled switching.
3208		 */
3209		return fg_console;
3210	case TIOCL_SCROLLCONSOLE:
3211		if (get_user(lines, (s32 __user *)(p+4)))
3212			return -EFAULT;
3213
3214		/*
3215		 * Needs the console lock here. Note that lots of other calls
3216		 * need fixing before the lock is actually useful!
3217		 */
3218		console_lock();
3219		scrollfront(vc_cons[fg_console].d, lines);
3220		console_unlock();
3221		break;
3222	case TIOCL_BLANKSCREEN:	/* until explicitly unblanked, not only poked */
3223		console_lock();
3224		ignore_poke = 1;
3225		do_blank_screen(0);
3226		console_unlock();
3227		break;
3228	case TIOCL_BLANKEDSCREEN:
3229		return console_blanked;
3230	default:
3231		return -EINVAL;
3232	}
3233
3234	return ret;
3235}
3236
3237/*
3238 * /dev/ttyN handling
3239 */
3240
3241static ssize_t con_write(struct tty_struct *tty, const u8 *buf, size_t count)
3242{
3243	int	retval;
3244
3245	retval = do_con_write(tty, buf, count);
3246	con_flush_chars(tty);
3247
3248	return retval;
3249}
3250
3251static int con_put_char(struct tty_struct *tty, u8 ch)
3252{
3253	return do_con_write(tty, &ch, 1);
3254}
3255
3256static unsigned int con_write_room(struct tty_struct *tty)
3257{
3258	if (tty->flow.stopped)
3259		return 0;
3260	return 32768;		/* No limit, really; we're not buffering */
3261}
3262
3263/*
3264 * con_throttle and con_unthrottle are only used for
3265 * paste_selection(), which has to stuff in a large number of
3266 * characters...
3267 */
3268static void con_throttle(struct tty_struct *tty)
3269{
3270}
3271
3272static void con_unthrottle(struct tty_struct *tty)
3273{
3274	struct vc_data *vc = tty->driver_data;
3275
3276	wake_up_interruptible(&vc->paste_wait);
3277}
3278
3279/*
3280 * Turn the Scroll-Lock LED on when the tty is stopped
3281 */
3282static void con_stop(struct tty_struct *tty)
3283{
3284	int console_num;
3285	if (!tty)
3286		return;
3287	console_num = tty->index;
3288	if (!vc_cons_allocated(console_num))
3289		return;
3290	vt_kbd_con_stop(console_num);
3291}
3292
3293/*
3294 * Turn the Scroll-Lock LED off when the console is started
3295 */
3296static void con_start(struct tty_struct *tty)
3297{
3298	int console_num;
3299	if (!tty)
3300		return;
3301	console_num = tty->index;
3302	if (!vc_cons_allocated(console_num))
3303		return;
3304	vt_kbd_con_start(console_num);
3305}
3306
3307static void con_flush_chars(struct tty_struct *tty)
3308{
3309	struct vc_data *vc;
3310
3311	if (in_interrupt())	/* from flush_to_ldisc */
3312		return;
3313
3314	/* if we race with con_close(), vt may be null */
3315	console_lock();
3316	vc = tty->driver_data;
3317	if (vc)
3318		set_cursor(vc);
3319	console_unlock();
3320}
3321
3322/*
3323 * Allocate the console screen memory.
3324 */
3325static int con_install(struct tty_driver *driver, struct tty_struct *tty)
3326{
3327	unsigned int currcons = tty->index;
3328	struct vc_data *vc;
3329	int ret;
3330
3331	console_lock();
3332	ret = vc_allocate(currcons);
3333	if (ret)
3334		goto unlock;
3335
3336	vc = vc_cons[currcons].d;
3337
3338	/* Still being freed */
3339	if (vc->port.tty) {
3340		ret = -ERESTARTSYS;
3341		goto unlock;
3342	}
3343
3344	ret = tty_port_install(&vc->port, driver, tty);
3345	if (ret)
3346		goto unlock;
3347
3348	tty->driver_data = vc;
3349	vc->port.tty = tty;
3350	tty_port_get(&vc->port);
3351
3352	if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
3353		tty->winsize.ws_row = vc_cons[currcons].d->vc_rows;
3354		tty->winsize.ws_col = vc_cons[currcons].d->vc_cols;
3355	}
3356	if (vc->vc_utf)
3357		tty->termios.c_iflag |= IUTF8;
3358	else
3359		tty->termios.c_iflag &= ~IUTF8;
3360unlock:
3361	console_unlock();
3362	return ret;
3363}
3364
3365static int con_open(struct tty_struct *tty, struct file *filp)
3366{
3367	/* everything done in install */
3368	return 0;
3369}
3370
3371
3372static void con_close(struct tty_struct *tty, struct file *filp)
3373{
3374	/* Nothing to do - we defer to shutdown */
3375}
3376
3377static void con_shutdown(struct tty_struct *tty)
3378{
3379	struct vc_data *vc = tty->driver_data;
3380	BUG_ON(vc == NULL);
3381	console_lock();
3382	vc->port.tty = NULL;
3383	console_unlock();
3384}
3385
3386static void con_cleanup(struct tty_struct *tty)
3387{
3388	struct vc_data *vc = tty->driver_data;
3389
3390	tty_port_put(&vc->port);
3391}
3392
3393static int default_color           = 7; /* white */
3394static int default_italic_color    = 2; // green (ASCII)
3395static int default_underline_color = 3; // cyan (ASCII)
3396module_param_named(color, default_color, int, S_IRUGO | S_IWUSR);
3397module_param_named(italic, default_italic_color, int, S_IRUGO | S_IWUSR);
3398module_param_named(underline, default_underline_color, int, S_IRUGO | S_IWUSR);
3399
3400static void vc_init(struct vc_data *vc, int do_clear)
3401{
3402	int j, k ;
3403
3404	set_origin(vc);
3405	vc->vc_pos = vc->vc_origin;
3406	reset_vc(vc);
3407	for (j=k=0; j<16; j++) {
3408		vc->vc_palette[k++] = default_red[j] ;
3409		vc->vc_palette[k++] = default_grn[j] ;
3410		vc->vc_palette[k++] = default_blu[j] ;
3411	}
3412	vc->vc_def_color       = default_color;
3413	vc->vc_ulcolor         = default_underline_color;
3414	vc->vc_itcolor         = default_italic_color;
3415	vc->vc_halfcolor       = 0x08;   /* grey */
3416	init_waitqueue_head(&vc->paste_wait);
3417	reset_terminal(vc, do_clear);
3418}
3419
3420/*
3421 * This routine initializes console interrupts, and does nothing
3422 * else. If you want the screen to clear, call tty_write with
3423 * the appropriate escape-sequence.
3424 */
3425
3426static int __init con_init(void)
3427{
3428	const char *display_desc = NULL;
3429	struct vc_data *vc;
3430	unsigned int currcons = 0, i;
3431
3432	console_lock();
3433
3434	if (!conswitchp)
3435		conswitchp = &dummy_con;
3436	display_desc = conswitchp->con_startup();
3437	if (!display_desc) {
3438		fg_console = 0;
3439		console_unlock();
3440		return 0;
3441	}
3442
3443	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3444		struct con_driver *con_driver = &registered_con_driver[i];
3445
3446		if (con_driver->con == NULL) {
3447			con_driver->con = conswitchp;
3448			con_driver->desc = display_desc;
3449			con_driver->flag = CON_DRIVER_FLAG_INIT;
3450			con_driver->first = 0;
3451			con_driver->last = MAX_NR_CONSOLES - 1;
3452			break;
3453		}
3454	}
3455
3456	for (i = 0; i < MAX_NR_CONSOLES; i++)
3457		con_driver_map[i] = conswitchp;
3458
3459	if (blankinterval) {
3460		blank_state = blank_normal_wait;
3461		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3462	}
3463
3464	for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) {
3465		vc_cons[currcons].d = vc = kzalloc(sizeof(struct vc_data), GFP_NOWAIT);
3466		INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
3467		tty_port_init(&vc->port);
3468		visual_init(vc, currcons, 1);
3469		/* Assuming vc->vc_{cols,rows,screenbuf_size} are sane here. */
3470		vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_NOWAIT);
3471		vc_init(vc, currcons || !vc->vc_sw->con_save_screen);
3472	}
3473	currcons = fg_console = 0;
3474	master_display_fg = vc = vc_cons[currcons].d;
3475	set_origin(vc);
3476	save_screen(vc);
3477	gotoxy(vc, vc->state.x, vc->state.y);
3478	csi_J(vc, 0);
3479	update_screen(vc);
3480	pr_info("Console: %s %s %dx%d\n",
3481		vc->vc_can_do_color ? "colour" : "mono",
3482		display_desc, vc->vc_cols, vc->vc_rows);
3483
3484	console_unlock();
3485
3486#ifdef CONFIG_VT_CONSOLE
3487	register_console(&vt_console_driver);
3488#endif
3489	return 0;
3490}
3491console_initcall(con_init);
3492
3493static const struct tty_operations con_ops = {
3494	.install = con_install,
3495	.open = con_open,
3496	.close = con_close,
3497	.write = con_write,
3498	.write_room = con_write_room,
3499	.put_char = con_put_char,
3500	.flush_chars = con_flush_chars,
3501	.ioctl = vt_ioctl,
3502#ifdef CONFIG_COMPAT
3503	.compat_ioctl = vt_compat_ioctl,
3504#endif
3505	.stop = con_stop,
3506	.start = con_start,
3507	.throttle = con_throttle,
3508	.unthrottle = con_unthrottle,
3509	.resize = vt_resize,
3510	.shutdown = con_shutdown,
3511	.cleanup = con_cleanup,
3512};
3513
3514static struct cdev vc0_cdev;
3515
3516static ssize_t show_tty_active(struct device *dev,
3517				struct device_attribute *attr, char *buf)
3518{
3519	return sprintf(buf, "tty%d\n", fg_console + 1);
3520}
3521static DEVICE_ATTR(active, S_IRUGO, show_tty_active, NULL);
3522
3523static struct attribute *vt_dev_attrs[] = {
3524	&dev_attr_active.attr,
3525	NULL
3526};
3527
3528ATTRIBUTE_GROUPS(vt_dev);
3529
3530int __init vty_init(const struct file_operations *console_fops)
3531{
3532	cdev_init(&vc0_cdev, console_fops);
3533	if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
3534	    register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
3535		panic("Couldn't register /dev/tty0 driver\n");
3536	tty0dev = device_create_with_groups(&tty_class, NULL,
3537					    MKDEV(TTY_MAJOR, 0), NULL,
3538					    vt_dev_groups, "tty0");
3539	if (IS_ERR(tty0dev))
3540		tty0dev = NULL;
3541
3542	vcs_init();
3543
3544	console_driver = tty_alloc_driver(MAX_NR_CONSOLES, TTY_DRIVER_REAL_RAW |
3545			TTY_DRIVER_RESET_TERMIOS);
3546	if (IS_ERR(console_driver))
3547		panic("Couldn't allocate console driver\n");
3548
3549	console_driver->name = "tty";
3550	console_driver->name_base = 1;
3551	console_driver->major = TTY_MAJOR;
3552	console_driver->minor_start = 1;
3553	console_driver->type = TTY_DRIVER_TYPE_CONSOLE;
3554	console_driver->init_termios = tty_std_termios;
3555	if (default_utf8)
3556		console_driver->init_termios.c_iflag |= IUTF8;
3557	tty_set_operations(console_driver, &con_ops);
3558	if (tty_register_driver(console_driver))
3559		panic("Couldn't register console driver\n");
3560	kbd_init();
3561	console_map_init();
3562#ifdef CONFIG_MDA_CONSOLE
3563	mda_console_init();
3564#endif
3565	return 0;
3566}
3567
3568static struct class *vtconsole_class;
3569
3570static int do_bind_con_driver(const struct consw *csw, int first, int last,
3571			   int deflt)
3572{
3573	struct module *owner = csw->owner;
3574	const char *desc = NULL;
3575	struct con_driver *con_driver;
3576	int i, j = -1, k = -1, retval = -ENODEV;
3577
3578	if (!try_module_get(owner))
3579		return -ENODEV;
3580
3581	WARN_CONSOLE_UNLOCKED();
3582
3583	/* check if driver is registered */
3584	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3585		con_driver = &registered_con_driver[i];
3586
3587		if (con_driver->con == csw) {
3588			desc = con_driver->desc;
3589			retval = 0;
3590			break;
3591		}
3592	}
3593
3594	if (retval)
3595		goto err;
3596
3597	if (!(con_driver->flag & CON_DRIVER_FLAG_INIT)) {
3598		csw->con_startup();
3599		con_driver->flag |= CON_DRIVER_FLAG_INIT;
3600	}
3601
3602	if (deflt) {
3603		if (conswitchp)
3604			module_put(conswitchp->owner);
3605
3606		__module_get(owner);
3607		conswitchp = csw;
3608	}
3609
3610	first = max(first, con_driver->first);
3611	last = min(last, con_driver->last);
3612
3613	for (i = first; i <= last; i++) {
3614		int old_was_color;
3615		struct vc_data *vc = vc_cons[i].d;
3616
3617		if (con_driver_map[i])
3618			module_put(con_driver_map[i]->owner);
3619		__module_get(owner);
3620		con_driver_map[i] = csw;
3621
3622		if (!vc || !vc->vc_sw)
3623			continue;
3624
3625		j = i;
3626
3627		if (con_is_visible(vc)) {
3628			k = i;
3629			save_screen(vc);
3630		}
3631
3632		old_was_color = vc->vc_can_do_color;
3633		vc->vc_sw->con_deinit(vc);
3634		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
3635		visual_init(vc, i, 0);
3636		set_origin(vc);
3637		update_attr(vc);
3638
3639		/* If the console changed between mono <-> color, then
3640		 * the attributes in the screenbuf will be wrong.  The
3641		 * following resets all attributes to something sane.
3642		 */
3643		if (old_was_color != vc->vc_can_do_color)
3644			clear_buffer_attributes(vc);
3645	}
3646
3647	pr_info("Console: switching ");
3648	if (!deflt)
3649		pr_cont("consoles %d-%d ", first + 1, last + 1);
3650	if (j >= 0) {
3651		struct vc_data *vc = vc_cons[j].d;
3652
3653		pr_cont("to %s %s %dx%d\n",
3654			vc->vc_can_do_color ? "colour" : "mono",
3655			desc, vc->vc_cols, vc->vc_rows);
3656
3657		if (k >= 0) {
3658			vc = vc_cons[k].d;
3659			update_screen(vc);
3660		}
3661	} else {
3662		pr_cont("to %s\n", desc);
3663	}
3664
3665	retval = 0;
3666err:
3667	module_put(owner);
3668	return retval;
3669};
3670
3671
3672#ifdef CONFIG_VT_HW_CONSOLE_BINDING
3673int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
3674{
3675	struct module *owner = csw->owner;
3676	const struct consw *defcsw = NULL;
3677	struct con_driver *con_driver = NULL, *con_back = NULL;
3678	int i, retval = -ENODEV;
3679
3680	if (!try_module_get(owner))
3681		return -ENODEV;
3682
3683	WARN_CONSOLE_UNLOCKED();
3684
3685	/* check if driver is registered and if it is unbindable */
3686	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3687		con_driver = &registered_con_driver[i];
3688
3689		if (con_driver->con == csw &&
3690		    con_driver->flag & CON_DRIVER_FLAG_MODULE) {
3691			retval = 0;
3692			break;
3693		}
3694	}
3695
3696	if (retval)
3697		goto err;
3698
3699	retval = -ENODEV;
3700
3701	/* check if backup driver exists */
3702	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3703		con_back = &registered_con_driver[i];
3704
3705		if (con_back->con && con_back->con != csw) {
3706			defcsw = con_back->con;
3707			retval = 0;
3708			break;
3709		}
3710	}
3711
3712	if (retval)
3713		goto err;
3714
3715	if (!con_is_bound(csw))
3716		goto err;
3717
3718	first = max(first, con_driver->first);
3719	last = min(last, con_driver->last);
3720
3721	for (i = first; i <= last; i++) {
3722		if (con_driver_map[i] == csw) {
3723			module_put(csw->owner);
3724			con_driver_map[i] = NULL;
3725		}
3726	}
3727
3728	if (!con_is_bound(defcsw)) {
3729		const struct consw *defconsw = conswitchp;
3730
3731		defcsw->con_startup();
3732		con_back->flag |= CON_DRIVER_FLAG_INIT;
3733		/*
3734		 * vgacon may change the default driver to point
3735		 * to dummycon, we restore it here...
3736		 */
3737		conswitchp = defconsw;
3738	}
3739
3740	if (!con_is_bound(csw))
3741		con_driver->flag &= ~CON_DRIVER_FLAG_INIT;
3742
3743	/* ignore return value, binding should not fail */
3744	do_bind_con_driver(defcsw, first, last, deflt);
3745err:
3746	module_put(owner);
3747	return retval;
3748
3749}
3750EXPORT_SYMBOL_GPL(do_unbind_con_driver);
3751
3752static int vt_bind(struct con_driver *con)
3753{
3754	const struct consw *defcsw = NULL, *csw = NULL;
3755	int i, more = 1, first = -1, last = -1, deflt = 0;
3756
3757 	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3758		goto err;
3759
3760	csw = con->con;
3761
3762	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3763		struct con_driver *con = &registered_con_driver[i];
3764
3765		if (con->con && !(con->flag & CON_DRIVER_FLAG_MODULE)) {
3766			defcsw = con->con;
3767			break;
3768		}
3769	}
3770
3771	if (!defcsw)
3772		goto err;
3773
3774	while (more) {
3775		more = 0;
3776
3777		for (i = con->first; i <= con->last; i++) {
3778			if (con_driver_map[i] == defcsw) {
3779				if (first == -1)
3780					first = i;
3781				last = i;
3782				more = 1;
3783			} else if (first != -1)
3784				break;
3785		}
3786
3787		if (first == 0 && last == MAX_NR_CONSOLES -1)
3788			deflt = 1;
3789
3790		if (first != -1)
3791			do_bind_con_driver(csw, first, last, deflt);
3792
3793		first = -1;
3794		last = -1;
3795		deflt = 0;
3796	}
3797
3798err:
3799	return 0;
3800}
3801
3802static int vt_unbind(struct con_driver *con)
3803{
3804	const struct consw *csw = NULL;
3805	int i, more = 1, first = -1, last = -1, deflt = 0;
3806	int ret;
3807
3808 	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3809		goto err;
3810
3811	csw = con->con;
3812
3813	while (more) {
3814		more = 0;
3815
3816		for (i = con->first; i <= con->last; i++) {
3817			if (con_driver_map[i] == csw) {
3818				if (first == -1)
3819					first = i;
3820				last = i;
3821				more = 1;
3822			} else if (first != -1)
3823				break;
3824		}
3825
3826		if (first == 0 && last == MAX_NR_CONSOLES -1)
3827			deflt = 1;
3828
3829		if (first != -1) {
3830			ret = do_unbind_con_driver(csw, first, last, deflt);
3831			if (ret != 0)
3832				return ret;
3833		}
3834
3835		first = -1;
3836		last = -1;
3837		deflt = 0;
3838	}
3839
3840err:
3841	return 0;
3842}
3843#else
3844static inline int vt_bind(struct con_driver *con)
3845{
3846	return 0;
3847}
3848static inline int vt_unbind(struct con_driver *con)
3849{
3850	return 0;
3851}
3852#endif /* CONFIG_VT_HW_CONSOLE_BINDING */
3853
3854static ssize_t store_bind(struct device *dev, struct device_attribute *attr,
3855			  const char *buf, size_t count)
3856{
3857	struct con_driver *con = dev_get_drvdata(dev);
3858	int bind = simple_strtoul(buf, NULL, 0);
3859
3860	console_lock();
3861
3862	if (bind)
3863		vt_bind(con);
3864	else
3865		vt_unbind(con);
3866
3867	console_unlock();
3868
3869	return count;
3870}
3871
3872static ssize_t show_bind(struct device *dev, struct device_attribute *attr,
3873			 char *buf)
3874{
3875	struct con_driver *con = dev_get_drvdata(dev);
3876	int bind;
3877
3878	console_lock();
3879	bind = con_is_bound(con->con);
3880	console_unlock();
3881
3882	return sysfs_emit(buf, "%i\n", bind);
3883}
3884
3885static ssize_t show_name(struct device *dev, struct device_attribute *attr,
3886			 char *buf)
3887{
3888	struct con_driver *con = dev_get_drvdata(dev);
3889
3890	return sysfs_emit(buf, "%s %s\n",
3891			(con->flag & CON_DRIVER_FLAG_MODULE) ? "(M)" : "(S)",
3892			 con->desc);
3893
3894}
3895
3896static DEVICE_ATTR(bind, S_IRUGO|S_IWUSR, show_bind, store_bind);
3897static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
3898
3899static struct attribute *con_dev_attrs[] = {
3900	&dev_attr_bind.attr,
3901	&dev_attr_name.attr,
3902	NULL
3903};
3904
3905ATTRIBUTE_GROUPS(con_dev);
3906
3907static int vtconsole_init_device(struct con_driver *con)
3908{
3909	con->flag |= CON_DRIVER_FLAG_ATTR;
3910	return 0;
3911}
3912
3913static void vtconsole_deinit_device(struct con_driver *con)
3914{
3915	con->flag &= ~CON_DRIVER_FLAG_ATTR;
3916}
3917
3918/**
3919 * con_is_bound - checks if driver is bound to the console
3920 * @csw: console driver
3921 *
3922 * RETURNS: zero if unbound, nonzero if bound
3923 *
3924 * Drivers can call this and if zero, they should release
3925 * all resources allocated on con_startup()
3926 */
3927int con_is_bound(const struct consw *csw)
3928{
3929	int i, bound = 0;
3930
3931	WARN_CONSOLE_UNLOCKED();
3932
3933	for (i = 0; i < MAX_NR_CONSOLES; i++) {
3934		if (con_driver_map[i] == csw) {
3935			bound = 1;
3936			break;
3937		}
3938	}
3939
3940	return bound;
3941}
3942EXPORT_SYMBOL(con_is_bound);
3943
3944/**
3945 * con_is_visible - checks whether the current console is visible
3946 * @vc: virtual console
3947 *
3948 * RETURNS: zero if not visible, nonzero if visible
3949 */
3950bool con_is_visible(const struct vc_data *vc)
3951{
3952	WARN_CONSOLE_UNLOCKED();
3953
3954	return *vc->vc_display_fg == vc;
3955}
3956EXPORT_SYMBOL(con_is_visible);
3957
3958/**
3959 * con_debug_enter - prepare the console for the kernel debugger
3960 * @vc: virtual console
3961 *
3962 * Called when the console is taken over by the kernel debugger, this
3963 * function needs to save the current console state, then put the console
3964 * into a state suitable for the kernel debugger.
3965 *
3966 * RETURNS:
3967 * Zero on success, nonzero if a failure occurred when trying to prepare
3968 * the console for the debugger.
3969 */
3970int con_debug_enter(struct vc_data *vc)
3971{
3972	int ret = 0;
3973
3974	saved_fg_console = fg_console;
3975	saved_last_console = last_console;
3976	saved_want_console = want_console;
3977	saved_vc_mode = vc->vc_mode;
3978	saved_console_blanked = console_blanked;
3979	vc->vc_mode = KD_TEXT;
3980	console_blanked = 0;
3981	if (vc->vc_sw->con_debug_enter)
3982		ret = vc->vc_sw->con_debug_enter(vc);
3983#ifdef CONFIG_KGDB_KDB
3984	/* Set the initial LINES variable if it is not already set */
3985	if (vc->vc_rows < 999) {
3986		int linecount;
3987		char lns[4];
3988		const char *setargs[3] = {
3989			"set",
3990			"LINES",
3991			lns,
3992		};
3993		if (kdbgetintenv(setargs[0], &linecount)) {
3994			snprintf(lns, 4, "%i", vc->vc_rows);
3995			kdb_set(2, setargs);
3996		}
3997	}
3998	if (vc->vc_cols < 999) {
3999		int colcount;
4000		char cols[4];
4001		const char *setargs[3] = {
4002			"set",
4003			"COLUMNS",
4004			cols,
4005		};
4006		if (kdbgetintenv(setargs[0], &colcount)) {
4007			snprintf(cols, 4, "%i", vc->vc_cols);
4008			kdb_set(2, setargs);
4009		}
4010	}
4011#endif /* CONFIG_KGDB_KDB */
4012	return ret;
4013}
4014EXPORT_SYMBOL_GPL(con_debug_enter);
4015
4016/**
4017 * con_debug_leave - restore console state
4018 *
4019 * Restore the console state to what it was before the kernel debugger
4020 * was invoked.
4021 *
4022 * RETURNS:
4023 * Zero on success, nonzero if a failure occurred when trying to restore
4024 * the console.
4025 */
4026int con_debug_leave(void)
4027{
4028	struct vc_data *vc;
4029	int ret = 0;
4030
4031	fg_console = saved_fg_console;
4032	last_console = saved_last_console;
4033	want_console = saved_want_console;
4034	console_blanked = saved_console_blanked;
4035	vc_cons[fg_console].d->vc_mode = saved_vc_mode;
4036
4037	vc = vc_cons[fg_console].d;
4038	if (vc->vc_sw->con_debug_leave)
4039		ret = vc->vc_sw->con_debug_leave(vc);
4040	return ret;
4041}
4042EXPORT_SYMBOL_GPL(con_debug_leave);
4043
4044static int do_register_con_driver(const struct consw *csw, int first, int last)
4045{
4046	struct module *owner = csw->owner;
4047	struct con_driver *con_driver;
4048	const char *desc;
4049	int i, retval;
4050
4051	WARN_CONSOLE_UNLOCKED();
4052
4053	if (!try_module_get(owner))
4054		return -ENODEV;
4055
4056	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4057		con_driver = &registered_con_driver[i];
4058
4059		/* already registered */
4060		if (con_driver->con == csw) {
4061			retval = -EBUSY;
4062			goto err;
4063		}
4064	}
4065
4066	desc = csw->con_startup();
4067	if (!desc) {
4068		retval = -ENODEV;
4069		goto err;
4070	}
4071
4072	retval = -EINVAL;
4073
4074	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4075		con_driver = &registered_con_driver[i];
4076
4077		if (con_driver->con == NULL &&
4078		    !(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE)) {
4079			con_driver->con = csw;
4080			con_driver->desc = desc;
4081			con_driver->node = i;
4082			con_driver->flag = CON_DRIVER_FLAG_MODULE |
4083			                   CON_DRIVER_FLAG_INIT;
4084			con_driver->first = first;
4085			con_driver->last = last;
4086			retval = 0;
4087			break;
4088		}
4089	}
4090
4091	if (retval)
4092		goto err;
4093
4094	con_driver->dev =
4095		device_create_with_groups(vtconsole_class, NULL,
4096					  MKDEV(0, con_driver->node),
4097					  con_driver, con_dev_groups,
4098					  "vtcon%i", con_driver->node);
4099	if (IS_ERR(con_driver->dev)) {
4100		pr_warn("Unable to create device for %s; errno = %ld\n",
4101			con_driver->desc, PTR_ERR(con_driver->dev));
4102		con_driver->dev = NULL;
4103	} else {
4104		vtconsole_init_device(con_driver);
4105	}
4106
4107err:
4108	module_put(owner);
4109	return retval;
4110}
4111
4112
4113/**
4114 * do_unregister_con_driver - unregister console driver from console layer
4115 * @csw: console driver
4116 *
4117 * DESCRIPTION: All drivers that registers to the console layer must
4118 * call this function upon exit, or if the console driver is in a state
4119 * where it won't be able to handle console services, such as the
4120 * framebuffer console without loaded framebuffer drivers.
4121 *
4122 * The driver must unbind first prior to unregistration.
4123 */
4124int do_unregister_con_driver(const struct consw *csw)
4125{
4126	int i;
4127
4128	/* cannot unregister a bound driver */
4129	if (con_is_bound(csw))
4130		return -EBUSY;
4131
4132	if (csw == conswitchp)
4133		return -EINVAL;
4134
4135	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4136		struct con_driver *con_driver = &registered_con_driver[i];
4137
4138		if (con_driver->con == csw) {
4139			/*
4140			 * Defer the removal of the sysfs entries since that
4141			 * will acquire the kernfs s_active lock and we can't
4142			 * acquire this lock while holding the console lock:
4143			 * the unbind sysfs entry imposes already the opposite
4144			 * order. Reset con already here to prevent any later
4145			 * lookup to succeed and mark this slot as zombie, so
4146			 * it won't get reused until we complete the removal
4147			 * in the deferred work.
4148			 */
4149			con_driver->con = NULL;
4150			con_driver->flag = CON_DRIVER_FLAG_ZOMBIE;
4151			schedule_work(&con_driver_unregister_work);
4152
4153			return 0;
4154		}
4155	}
4156
4157	return -ENODEV;
4158}
4159EXPORT_SYMBOL_GPL(do_unregister_con_driver);
4160
4161static void con_driver_unregister_callback(struct work_struct *ignored)
4162{
4163	int i;
4164
4165	console_lock();
4166
4167	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4168		struct con_driver *con_driver = &registered_con_driver[i];
4169
4170		if (!(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE))
4171			continue;
4172
4173		console_unlock();
4174
4175		vtconsole_deinit_device(con_driver);
4176		device_destroy(vtconsole_class, MKDEV(0, con_driver->node));
4177
4178		console_lock();
4179
4180		if (WARN_ON_ONCE(con_driver->con))
4181			con_driver->con = NULL;
4182		con_driver->desc = NULL;
4183		con_driver->dev = NULL;
4184		con_driver->node = 0;
4185		WARN_ON_ONCE(con_driver->flag != CON_DRIVER_FLAG_ZOMBIE);
4186		con_driver->flag = 0;
4187		con_driver->first = 0;
4188		con_driver->last = 0;
4189	}
4190
4191	console_unlock();
4192}
4193
4194/*
4195 *	If we support more console drivers, this function is used
4196 *	when a driver wants to take over some existing consoles
4197 *	and become default driver for newly opened ones.
4198 *
4199 *	do_take_over_console is basically a register followed by bind
4200 */
4201int do_take_over_console(const struct consw *csw, int first, int last, int deflt)
4202{
4203	int err;
4204
4205	err = do_register_con_driver(csw, first, last);
4206	/*
4207	 * If we get an busy error we still want to bind the console driver
4208	 * and return success, as we may have unbound the console driver
4209	 * but not unregistered it.
4210	 */
4211	if (err == -EBUSY)
4212		err = 0;
4213	if (!err)
4214		do_bind_con_driver(csw, first, last, deflt);
4215
4216	return err;
4217}
4218EXPORT_SYMBOL_GPL(do_take_over_console);
4219
4220
4221/*
4222 * give_up_console is a wrapper to unregister_con_driver. It will only
4223 * work if driver is fully unbound.
4224 */
4225void give_up_console(const struct consw *csw)
4226{
4227	console_lock();
4228	do_unregister_con_driver(csw);
4229	console_unlock();
4230}
4231EXPORT_SYMBOL(give_up_console);
4232
4233static int __init vtconsole_class_init(void)
4234{
4235	int i;
4236
4237	vtconsole_class = class_create("vtconsole");
4238	if (IS_ERR(vtconsole_class)) {
4239		pr_warn("Unable to create vt console class; errno = %ld\n",
4240			PTR_ERR(vtconsole_class));
4241		vtconsole_class = NULL;
4242	}
4243
4244	/* Add system drivers to sysfs */
4245	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4246		struct con_driver *con = &registered_con_driver[i];
4247
4248		if (con->con && !con->dev) {
4249			con->dev =
4250				device_create_with_groups(vtconsole_class, NULL,
4251							  MKDEV(0, con->node),
4252							  con, con_dev_groups,
4253							  "vtcon%i", con->node);
4254
4255			if (IS_ERR(con->dev)) {
4256				pr_warn("Unable to create device for %s; errno = %ld\n",
4257					con->desc, PTR_ERR(con->dev));
4258				con->dev = NULL;
4259			} else {
4260				vtconsole_init_device(con);
4261			}
4262		}
4263	}
4264
4265	return 0;
4266}
4267postcore_initcall(vtconsole_class_init);
4268
4269/*
4270 *	Screen blanking
4271 */
4272
4273static int set_vesa_blanking(char __user *p)
4274{
4275	unsigned int mode;
4276
4277	if (get_user(mode, p + 1))
4278		return -EFAULT;
4279
4280	vesa_blank_mode = (mode < 4) ? mode : 0;
4281	return 0;
4282}
4283
4284void do_blank_screen(int entering_gfx)
4285{
4286	struct vc_data *vc = vc_cons[fg_console].d;
4287	int i;
4288
4289	might_sleep();
4290
4291	WARN_CONSOLE_UNLOCKED();
4292
4293	if (console_blanked) {
4294		if (blank_state == blank_vesa_wait) {
4295			blank_state = blank_off;
4296			vc->vc_sw->con_blank(vc, vesa_blank_mode + 1, 0);
4297		}
4298		return;
4299	}
4300
4301	/* entering graphics mode? */
4302	if (entering_gfx) {
4303		hide_cursor(vc);
4304		save_screen(vc);
4305		vc->vc_sw->con_blank(vc, -1, 1);
4306		console_blanked = fg_console + 1;
4307		blank_state = blank_off;
4308		set_origin(vc);
4309		return;
4310	}
4311
4312	blank_state = blank_off;
4313
4314	/* don't blank graphics */
4315	if (vc->vc_mode != KD_TEXT) {
4316		console_blanked = fg_console + 1;
4317		return;
4318	}
4319
4320	hide_cursor(vc);
4321	del_timer_sync(&console_timer);
4322	blank_timer_expired = 0;
4323
4324	save_screen(vc);
4325	/* In case we need to reset origin, blanking hook returns 1 */
4326	i = vc->vc_sw->con_blank(vc, vesa_off_interval ? 1 : (vesa_blank_mode + 1), 0);
4327	console_blanked = fg_console + 1;
4328	if (i)
4329		set_origin(vc);
4330
4331	if (console_blank_hook && console_blank_hook(1))
4332		return;
4333
4334	if (vesa_off_interval && vesa_blank_mode) {
4335		blank_state = blank_vesa_wait;
4336		mod_timer(&console_timer, jiffies + vesa_off_interval);
4337	}
4338	vt_event_post(VT_EVENT_BLANK, vc->vc_num, vc->vc_num);
4339}
4340EXPORT_SYMBOL(do_blank_screen);
4341
4342/*
4343 * Called by timer as well as from vt_console_driver
4344 */
4345void do_unblank_screen(int leaving_gfx)
4346{
4347	struct vc_data *vc;
4348
4349	/* This should now always be called from a "sane" (read: can schedule)
4350	 * context for the sake of the low level drivers, except in the special
4351	 * case of oops_in_progress
4352	 */
4353	if (!oops_in_progress)
4354		might_sleep();
4355
4356	WARN_CONSOLE_UNLOCKED();
4357
4358	ignore_poke = 0;
4359	if (!console_blanked)
4360		return;
4361	if (!vc_cons_allocated(fg_console)) {
4362		/* impossible */
4363		pr_warn("unblank_screen: tty %d not allocated ??\n",
4364			fg_console + 1);
4365		return;
4366	}
4367	vc = vc_cons[fg_console].d;
4368	if (vc->vc_mode != KD_TEXT)
4369		return; /* but leave console_blanked != 0 */
4370
4371	if (blankinterval) {
4372		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4373		blank_state = blank_normal_wait;
4374	}
4375
4376	console_blanked = 0;
4377	if (vc->vc_sw->con_blank(vc, 0, leaving_gfx))
4378		/* Low-level driver cannot restore -> do it ourselves */
4379		update_screen(vc);
4380	if (console_blank_hook)
4381		console_blank_hook(0);
4382	set_palette(vc);
4383	set_cursor(vc);
4384	vt_event_post(VT_EVENT_UNBLANK, vc->vc_num, vc->vc_num);
4385}
4386EXPORT_SYMBOL(do_unblank_screen);
4387
4388/*
4389 * This is called by the outside world to cause a forced unblank, mostly for
4390 * oopses. Currently, I just call do_unblank_screen(0), but we could eventually
4391 * call it with 1 as an argument and so force a mode restore... that may kill
4392 * X or at least garbage the screen but would also make the Oops visible...
4393 */
4394static void unblank_screen(void)
4395{
4396	do_unblank_screen(0);
4397}
4398
4399/*
4400 * We defer the timer blanking to work queue so it can take the console mutex
4401 * (console operations can still happen at irq time, but only from printk which
4402 * has the console mutex. Not perfect yet, but better than no locking
4403 */
4404static void blank_screen_t(struct timer_list *unused)
4405{
4406	blank_timer_expired = 1;
4407	schedule_work(&console_work);
4408}
4409
4410void poke_blanked_console(void)
4411{
4412	WARN_CONSOLE_UNLOCKED();
4413
4414	/* Add this so we quickly catch whoever might call us in a non
4415	 * safe context. Nowadays, unblank_screen() isn't to be called in
4416	 * atomic contexts and is allowed to schedule (with the special case
4417	 * of oops_in_progress, but that isn't of any concern for this
4418	 * function. --BenH.
4419	 */
4420	might_sleep();
4421
4422	/* This isn't perfectly race free, but a race here would be mostly harmless,
4423	 * at worst, we'll do a spurious blank and it's unlikely
4424	 */
4425	del_timer(&console_timer);
4426	blank_timer_expired = 0;
4427
4428	if (ignore_poke || !vc_cons[fg_console].d || vc_cons[fg_console].d->vc_mode == KD_GRAPHICS)
4429		return;
4430	if (console_blanked)
4431		unblank_screen();
4432	else if (blankinterval) {
4433		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4434		blank_state = blank_normal_wait;
4435	}
4436}
4437
4438/*
4439 *	Palettes
4440 */
4441
4442static void set_palette(struct vc_data *vc)
4443{
4444	WARN_CONSOLE_UNLOCKED();
4445
4446	if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_set_palette)
4447		vc->vc_sw->con_set_palette(vc, color_table);
4448}
4449
4450/*
4451 * Load palette into the DAC registers. arg points to a colour
4452 * map, 3 bytes per colour, 16 colours, range from 0 to 255.
4453 */
4454
4455int con_set_cmap(unsigned char __user *arg)
4456{
4457	int i, j, k;
4458	unsigned char colormap[3*16];
4459
4460	if (copy_from_user(colormap, arg, sizeof(colormap)))
4461		return -EFAULT;
4462
4463	console_lock();
4464	for (i = k = 0; i < 16; i++) {
4465		default_red[i] = colormap[k++];
4466		default_grn[i] = colormap[k++];
4467		default_blu[i] = colormap[k++];
4468	}
4469	for (i = 0; i < MAX_NR_CONSOLES; i++) {
4470		if (!vc_cons_allocated(i))
4471			continue;
4472		for (j = k = 0; j < 16; j++) {
4473			vc_cons[i].d->vc_palette[k++] = default_red[j];
4474			vc_cons[i].d->vc_palette[k++] = default_grn[j];
4475			vc_cons[i].d->vc_palette[k++] = default_blu[j];
4476		}
4477		set_palette(vc_cons[i].d);
4478	}
4479	console_unlock();
4480
4481	return 0;
4482}
4483
4484int con_get_cmap(unsigned char __user *arg)
4485{
4486	int i, k;
4487	unsigned char colormap[3*16];
4488
4489	console_lock();
4490	for (i = k = 0; i < 16; i++) {
4491		colormap[k++] = default_red[i];
4492		colormap[k++] = default_grn[i];
4493		colormap[k++] = default_blu[i];
4494	}
4495	console_unlock();
4496
4497	if (copy_to_user(arg, colormap, sizeof(colormap)))
4498		return -EFAULT;
4499
4500	return 0;
4501}
4502
4503void reset_palette(struct vc_data *vc)
4504{
4505	int j, k;
4506	for (j=k=0; j<16; j++) {
4507		vc->vc_palette[k++] = default_red[j];
4508		vc->vc_palette[k++] = default_grn[j];
4509		vc->vc_palette[k++] = default_blu[j];
4510	}
4511	set_palette(vc);
4512}
4513
4514/*
4515 *  Font switching
4516 *
4517 *  Currently we only support fonts up to 128 pixels wide, at a maximum height
4518 *  of 128 pixels. Userspace fontdata may have to be stored with 32 bytes
4519 *  (shorts/ints, depending on width) reserved for each character which is
4520 *  kinda wasty, but this is done in order to maintain compatibility with the
4521 *  EGA/VGA fonts. It is up to the actual low-level console-driver convert data
4522 *  into its favorite format (maybe we should add a `fontoffset' field to the
4523 *  `display' structure so we won't have to convert the fontdata all the time.
4524 *  /Jes
4525 */
4526
4527#define max_font_width	64
4528#define max_font_height	128
4529#define max_font_glyphs	512
4530#define max_font_size	(max_font_glyphs*max_font_width*max_font_height)
4531
4532static int con_font_get(struct vc_data *vc, struct console_font_op *op)
4533{
4534	struct console_font font;
4535	int rc = -EINVAL;
4536	int c;
4537	unsigned int vpitch = op->op == KD_FONT_OP_GET_TALL ? op->height : 32;
4538
4539	if (vpitch > max_font_height)
4540		return -EINVAL;
4541
4542	if (op->data) {
4543		font.data = kvmalloc(max_font_size, GFP_KERNEL);
4544		if (!font.data)
4545			return -ENOMEM;
4546	} else
4547		font.data = NULL;
4548
4549	console_lock();
4550	if (vc->vc_mode != KD_TEXT)
4551		rc = -EINVAL;
4552	else if (vc->vc_sw->con_font_get)
4553		rc = vc->vc_sw->con_font_get(vc, &font, vpitch);
4554	else
4555		rc = -ENOSYS;
4556	console_unlock();
4557
4558	if (rc)
4559		goto out;
4560
4561	c = (font.width+7)/8 * vpitch * font.charcount;
4562
4563	if (op->data && font.charcount > op->charcount)
4564		rc = -ENOSPC;
4565	if (font.width > op->width || font.height > op->height)
4566		rc = -ENOSPC;
4567	if (rc)
4568		goto out;
4569
4570	op->height = font.height;
4571	op->width = font.width;
4572	op->charcount = font.charcount;
4573
4574	if (op->data && copy_to_user(op->data, font.data, c))
4575		rc = -EFAULT;
4576
4577out:
4578	kvfree(font.data);
4579	return rc;
4580}
4581
4582static int con_font_set(struct vc_data *vc, struct console_font_op *op)
4583{
4584	struct console_font font;
4585	int rc = -EINVAL;
4586	int size;
4587	unsigned int vpitch = op->op == KD_FONT_OP_SET_TALL ? op->height : 32;
4588
4589	if (vc->vc_mode != KD_TEXT)
4590		return -EINVAL;
4591	if (!op->data)
4592		return -EINVAL;
4593	if (op->charcount > max_font_glyphs)
4594		return -EINVAL;
4595	if (op->width <= 0 || op->width > max_font_width || !op->height ||
4596	    op->height > max_font_height)
4597		return -EINVAL;
4598	if (vpitch < op->height)
4599		return -EINVAL;
4600	size = (op->width+7)/8 * vpitch * op->charcount;
4601	if (size > max_font_size)
4602		return -ENOSPC;
4603
4604	font.data = memdup_user(op->data, size);
4605	if (IS_ERR(font.data))
4606		return PTR_ERR(font.data);
4607
4608	font.charcount = op->charcount;
4609	font.width = op->width;
4610	font.height = op->height;
4611
4612	console_lock();
4613	if (vc->vc_mode != KD_TEXT)
4614		rc = -EINVAL;
4615	else if (vc->vc_sw->con_font_set) {
4616		if (vc_is_sel(vc))
4617			clear_selection();
4618		rc = vc->vc_sw->con_font_set(vc, &font, vpitch, op->flags);
4619	} else
4620		rc = -ENOSYS;
4621	console_unlock();
4622	kfree(font.data);
4623	return rc;
4624}
4625
4626static int con_font_default(struct vc_data *vc, struct console_font_op *op)
4627{
4628	struct console_font font = {.width = op->width, .height = op->height};
4629	char name[MAX_FONT_NAME];
4630	char *s = name;
4631	int rc;
4632
4633
4634	if (!op->data)
4635		s = NULL;
4636	else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0)
4637		return -EFAULT;
4638	else
4639		name[MAX_FONT_NAME - 1] = 0;
4640
4641	console_lock();
4642	if (vc->vc_mode != KD_TEXT) {
4643		console_unlock();
4644		return -EINVAL;
4645	}
4646	if (vc->vc_sw->con_font_default) {
4647		if (vc_is_sel(vc))
4648			clear_selection();
4649		rc = vc->vc_sw->con_font_default(vc, &font, s);
4650	} else
4651		rc = -ENOSYS;
4652	console_unlock();
4653	if (!rc) {
4654		op->width = font.width;
4655		op->height = font.height;
4656	}
4657	return rc;
4658}
4659
4660int con_font_op(struct vc_data *vc, struct console_font_op *op)
4661{
4662	switch (op->op) {
4663	case KD_FONT_OP_SET:
4664	case KD_FONT_OP_SET_TALL:
4665		return con_font_set(vc, op);
4666	case KD_FONT_OP_GET:
4667	case KD_FONT_OP_GET_TALL:
4668		return con_font_get(vc, op);
4669	case KD_FONT_OP_SET_DEFAULT:
4670		return con_font_default(vc, op);
4671	case KD_FONT_OP_COPY:
4672		/* was buggy and never really used */
4673		return -EINVAL;
4674	}
4675	return -ENOSYS;
4676}
4677
4678/*
4679 *	Interface exported to selection and vcs.
4680 */
4681
4682/* used by selection */
4683u16 screen_glyph(const struct vc_data *vc, int offset)
4684{
4685	u16 w = scr_readw(screenpos(vc, offset, true));
4686	u16 c = w & 0xff;
4687
4688	if (w & vc->vc_hi_font_mask)
4689		c |= 0x100;
4690	return c;
4691}
4692EXPORT_SYMBOL_GPL(screen_glyph);
4693
4694u32 screen_glyph_unicode(const struct vc_data *vc, int n)
4695{
4696	u32 **uni_lines = vc->vc_uni_lines;
4697
4698	if (uni_lines)
4699		return uni_lines[n / vc->vc_cols][n % vc->vc_cols];
4700
4701	return inverse_translate(vc, screen_glyph(vc, n * 2), true);
4702}
4703EXPORT_SYMBOL_GPL(screen_glyph_unicode);
4704
4705/* used by vcs - note the word offset */
4706unsigned short *screen_pos(const struct vc_data *vc, int w_offset, bool viewed)
4707{
4708	return screenpos(vc, 2 * w_offset, viewed);
4709}
4710EXPORT_SYMBOL_GPL(screen_pos);
4711
4712void getconsxy(const struct vc_data *vc, unsigned char xy[static 2])
4713{
4714	/* clamp values if they don't fit */
4715	xy[0] = min(vc->state.x, 0xFFu);
4716	xy[1] = min(vc->state.y, 0xFFu);
4717}
4718
4719void putconsxy(struct vc_data *vc, unsigned char xy[static const 2])
4720{
4721	hide_cursor(vc);
4722	gotoxy(vc, xy[0], xy[1]);
4723	set_cursor(vc);
4724}
4725
4726u16 vcs_scr_readw(const struct vc_data *vc, const u16 *org)
4727{
4728	if ((unsigned long)org == vc->vc_pos && softcursor_original != -1)
4729		return softcursor_original;
4730	return scr_readw(org);
4731}
4732
4733void vcs_scr_writew(struct vc_data *vc, u16 val, u16 *org)
4734{
4735	scr_writew(val, org);
4736	if ((unsigned long)org == vc->vc_pos) {
4737		softcursor_original = -1;
4738		add_softcursor(vc);
4739	}
4740}
4741
4742void vcs_scr_updated(struct vc_data *vc)
4743{
4744	notify_update(vc);
4745}
4746
4747void vc_scrolldelta_helper(struct vc_data *c, int lines,
4748		unsigned int rolled_over, void *base, unsigned int size)
4749{
4750	unsigned long ubase = (unsigned long)base;
4751	ptrdiff_t scr_end = (void *)c->vc_scr_end - base;
4752	ptrdiff_t vorigin = (void *)c->vc_visible_origin - base;
4753	ptrdiff_t origin = (void *)c->vc_origin - base;
4754	int margin = c->vc_size_row * 4;
4755	int from, wrap, from_off, avail;
4756
4757	/* Turn scrollback off */
4758	if (!lines) {
4759		c->vc_visible_origin = c->vc_origin;
4760		return;
4761	}
4762
4763	/* Do we have already enough to allow jumping from 0 to the end? */
4764	if (rolled_over > scr_end + margin) {
4765		from = scr_end;
4766		wrap = rolled_over + c->vc_size_row;
4767	} else {
4768		from = 0;
4769		wrap = size;
4770	}
4771
4772	from_off = (vorigin - from + wrap) % wrap + lines * c->vc_size_row;
4773	avail = (origin - from + wrap) % wrap;
4774
4775	/* Only a little piece would be left? Show all incl. the piece! */
4776	if (avail < 2 * margin)
4777		margin = 0;
4778	if (from_off < margin)
4779		from_off = 0;
4780	if (from_off > avail - margin)
4781		from_off = avail;
4782
4783	c->vc_visible_origin = ubase + (from + from_off) % wrap;
4784}
4785EXPORT_SYMBOL_GPL(vc_scrolldelta_helper);
4786