xref: /kernel/linux/linux-5.10/drivers/tty/vt/vt.c (revision 8c2ecf20)
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];
138
139#ifndef VT_SINGLE_DRIVER
140static const struct consw *con_driver_map[MAX_NR_CONSOLES];
141#endif
142
143static int con_open(struct tty_struct *, struct file *);
144static void vc_init(struct vc_data *vc, unsigned int rows,
145		    unsigned int cols, int do_clear);
146static void gotoxy(struct vc_data *vc, int new_x, int new_y);
147static void save_cur(struct vc_data *vc);
148static void reset_terminal(struct vc_data *vc, int do_clear);
149static void con_flush_chars(struct tty_struct *tty);
150static int set_vesa_blanking(char __user *p);
151static void set_cursor(struct vc_data *vc);
152static void hide_cursor(struct vc_data *vc);
153static void console_callback(struct work_struct *ignored);
154static void con_driver_unregister_callback(struct work_struct *ignored);
155static void blank_screen_t(struct timer_list *unused);
156static void set_palette(struct vc_data *vc);
157
158#define vt_get_kmsg_redirect() vt_kmsg_redirect(-1)
159
160static int printable;		/* Is console ready for printing? */
161int default_utf8 = true;
162module_param(default_utf8, int, S_IRUGO | S_IWUSR);
163int global_cursor_default = -1;
164module_param(global_cursor_default, int, S_IRUGO | S_IWUSR);
165
166static int cur_default = CUR_UNDERLINE;
167module_param(cur_default, int, S_IRUGO | S_IWUSR);
168
169/*
170 * ignore_poke: don't unblank the screen when things are typed.  This is
171 * mainly for the privacy of braille terminal users.
172 */
173static int ignore_poke;
174
175int do_poke_blanked_console;
176int 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;
193int last_console;
194int want_console = -1;
195static int saved_fg_console;
196static int saved_last_console;
197static int saved_want_console;
198static int saved_vc_mode;
199static int saved_console_blanked;
200
201/*
202 * For each existing display, we have a pointer to console currently visible
203 * on that display, allowing consoles other than fg_console to be refreshed
204 * appropriately. Unless the low-level driver supplies its own display_fg
205 * variable, we use this one for the "master display".
206 */
207static struct vc_data *master_display_fg;
208
209/*
210 * Unfortunately, we need to delay tty echo when we're currently writing to the
211 * console since the code is (and always was) not re-entrant, so we schedule
212 * all flip requests to process context with schedule-task() and run it from
213 * console_callback().
214 */
215
216/*
217 * For the same reason, we defer scrollback to the console callback.
218 */
219static int scrollback_delta;
220
221/*
222 * Hook so that the power management routines can (un)blank
223 * the console on our behalf.
224 */
225int (*console_blank_hook)(int);
226
227static DEFINE_TIMER(console_timer, blank_screen_t);
228static int blank_state;
229static int blank_timer_expired;
230enum {
231	blank_off = 0,
232	blank_normal_wait,
233	blank_vesa_wait,
234};
235
236/*
237 * /sys/class/tty/tty0/
238 *
239 * the attribute 'active' contains the name of the current vc
240 * console and it supports poll() to detect vc switches
241 */
242static struct device *tty0dev;
243
244/*
245 * Notifier list for console events.
246 */
247static ATOMIC_NOTIFIER_HEAD(vt_notifier_list);
248
249int register_vt_notifier(struct notifier_block *nb)
250{
251	return atomic_notifier_chain_register(&vt_notifier_list, nb);
252}
253EXPORT_SYMBOL_GPL(register_vt_notifier);
254
255int unregister_vt_notifier(struct notifier_block *nb)
256{
257	return atomic_notifier_chain_unregister(&vt_notifier_list, nb);
258}
259EXPORT_SYMBOL_GPL(unregister_vt_notifier);
260
261static void notify_write(struct vc_data *vc, unsigned int unicode)
262{
263	struct vt_notifier_param param = { .vc = vc, .c = unicode };
264	atomic_notifier_call_chain(&vt_notifier_list, VT_WRITE, &param);
265}
266
267static void notify_update(struct vc_data *vc)
268{
269	struct vt_notifier_param param = { .vc = vc };
270	atomic_notifier_call_chain(&vt_notifier_list, VT_UPDATE, &param);
271}
272/*
273 *	Low-Level Functions
274 */
275
276static inline bool con_is_fg(const struct vc_data *vc)
277{
278	return vc->vc_num == fg_console;
279}
280
281static inline bool con_should_update(const struct vc_data *vc)
282{
283	return con_is_visible(vc) && !console_blanked;
284}
285
286static inline unsigned short *screenpos(const struct vc_data *vc, int offset,
287		bool viewed)
288{
289	unsigned short *p;
290
291	if (!viewed)
292		p = (unsigned short *)(vc->vc_origin + offset);
293	else if (!vc->vc_sw->con_screen_pos)
294		p = (unsigned short *)(vc->vc_visible_origin + offset);
295	else
296		p = vc->vc_sw->con_screen_pos(vc, offset);
297	return p;
298}
299
300/* Called  from the keyboard irq path.. */
301static inline void scrolldelta(int lines)
302{
303	/* FIXME */
304	/* scrolldelta needs some kind of consistency lock, but the BKL was
305	   and still is not protecting versus the scheduled back end */
306	scrollback_delta += lines;
307	schedule_console_callback();
308}
309
310void schedule_console_callback(void)
311{
312	schedule_work(&console_work);
313}
314
315/*
316 * Code to manage unicode-based screen buffers
317 */
318
319#ifdef NO_VC_UNI_SCREEN
320/* this disables and optimizes related code away at compile time */
321#define get_vc_uniscr(vc) NULL
322#else
323#define get_vc_uniscr(vc) vc->vc_uni_screen
324#endif
325
326#define VC_UNI_SCREEN_DEBUG 0
327
328typedef uint32_t char32_t;
329
330/*
331 * Our screen buffer is preceded by an array of line pointers so that
332 * scrolling only implies some pointer shuffling.
333 */
334struct uni_screen {
335	char32_t *lines[0];
336};
337
338static struct uni_screen *vc_uniscr_alloc(unsigned int cols, unsigned int rows)
339{
340	struct uni_screen *uniscr;
341	void *p;
342	unsigned int memsize, i;
343
344	/* allocate everything in one go */
345	memsize = cols * rows * sizeof(char32_t);
346	memsize += rows * sizeof(char32_t *);
347	p = vzalloc(memsize);
348	if (!p)
349		return NULL;
350
351	/* initial line pointers */
352	uniscr = p;
353	p = uniscr->lines + rows;
354	for (i = 0; i < rows; i++) {
355		uniscr->lines[i] = p;
356		p += cols * sizeof(char32_t);
357	}
358	return uniscr;
359}
360
361static void vc_uniscr_free(struct uni_screen *uniscr)
362{
363	vfree(uniscr);
364}
365
366static void vc_uniscr_set(struct vc_data *vc, struct uni_screen *new_uniscr)
367{
368	vc_uniscr_free(vc->vc_uni_screen);
369	vc->vc_uni_screen = new_uniscr;
370}
371
372static void vc_uniscr_putc(struct vc_data *vc, char32_t uc)
373{
374	struct uni_screen *uniscr = get_vc_uniscr(vc);
375
376	if (uniscr)
377		uniscr->lines[vc->state.y][vc->state.x] = uc;
378}
379
380static void vc_uniscr_insert(struct vc_data *vc, unsigned int nr)
381{
382	struct uni_screen *uniscr = get_vc_uniscr(vc);
383
384	if (uniscr) {
385		char32_t *ln = uniscr->lines[vc->state.y];
386		unsigned int x = vc->state.x, cols = vc->vc_cols;
387
388		memmove(&ln[x + nr], &ln[x], (cols - x - nr) * sizeof(*ln));
389		memset32(&ln[x], ' ', nr);
390	}
391}
392
393static void vc_uniscr_delete(struct vc_data *vc, unsigned int nr)
394{
395	struct uni_screen *uniscr = get_vc_uniscr(vc);
396
397	if (uniscr) {
398		char32_t *ln = uniscr->lines[vc->state.y];
399		unsigned int x = vc->state.x, cols = vc->vc_cols;
400
401		memmove(&ln[x], &ln[x + nr], (cols - x - nr) * sizeof(*ln));
402		memset32(&ln[cols - nr], ' ', nr);
403	}
404}
405
406static void vc_uniscr_clear_line(struct vc_data *vc, unsigned int x,
407				 unsigned int nr)
408{
409	struct uni_screen *uniscr = get_vc_uniscr(vc);
410
411	if (uniscr) {
412		char32_t *ln = uniscr->lines[vc->state.y];
413
414		memset32(&ln[x], ' ', nr);
415	}
416}
417
418static void vc_uniscr_clear_lines(struct vc_data *vc, unsigned int y,
419				  unsigned int nr)
420{
421	struct uni_screen *uniscr = get_vc_uniscr(vc);
422
423	if (uniscr) {
424		unsigned int cols = vc->vc_cols;
425
426		while (nr--)
427			memset32(uniscr->lines[y++], ' ', cols);
428	}
429}
430
431static void vc_uniscr_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
432			     enum con_scroll dir, unsigned int nr)
433{
434	struct uni_screen *uniscr = get_vc_uniscr(vc);
435
436	if (uniscr) {
437		unsigned int i, j, k, sz, d, clear;
438
439		sz = b - t;
440		clear = b - nr;
441		d = nr;
442		if (dir == SM_DOWN) {
443			clear = t;
444			d = sz - nr;
445		}
446		for (i = 0; i < gcd(d, sz); i++) {
447			char32_t *tmp = uniscr->lines[t + i];
448			j = i;
449			while (1) {
450				k = j + d;
451				if (k >= sz)
452					k -= sz;
453				if (k == i)
454					break;
455				uniscr->lines[t + j] = uniscr->lines[t + k];
456				j = k;
457			}
458			uniscr->lines[t + j] = tmp;
459		}
460		vc_uniscr_clear_lines(vc, clear, nr);
461	}
462}
463
464static void vc_uniscr_copy_area(struct uni_screen *dst,
465				unsigned int dst_cols,
466				unsigned int dst_rows,
467				struct uni_screen *src,
468				unsigned int src_cols,
469				unsigned int src_top_row,
470				unsigned int src_bot_row)
471{
472	unsigned int dst_row = 0;
473
474	if (!dst)
475		return;
476
477	while (src_top_row < src_bot_row) {
478		char32_t *src_line = src->lines[src_top_row];
479		char32_t *dst_line = dst->lines[dst_row];
480
481		memcpy(dst_line, src_line, src_cols * sizeof(char32_t));
482		if (dst_cols - src_cols)
483			memset32(dst_line + src_cols, ' ', dst_cols - src_cols);
484		src_top_row++;
485		dst_row++;
486	}
487	while (dst_row < dst_rows) {
488		char32_t *dst_line = dst->lines[dst_row];
489
490		memset32(dst_line, ' ', dst_cols);
491		dst_row++;
492	}
493}
494
495/*
496 * Called from vcs_read() to make sure unicode screen retrieval is possible.
497 * This will initialize the unicode screen buffer if not already done.
498 * This returns 0 if OK, or a negative error code otherwise.
499 * In particular, -ENODATA is returned if the console is not in UTF-8 mode.
500 */
501int vc_uniscr_check(struct vc_data *vc)
502{
503	struct uni_screen *uniscr;
504	unsigned short *p;
505	int x, y, mask;
506
507	if (__is_defined(NO_VC_UNI_SCREEN))
508		return -EOPNOTSUPP;
509
510	WARN_CONSOLE_UNLOCKED();
511
512	if (!vc->vc_utf)
513		return -ENODATA;
514
515	if (vc->vc_uni_screen)
516		return 0;
517
518	uniscr = vc_uniscr_alloc(vc->vc_cols, vc->vc_rows);
519	if (!uniscr)
520		return -ENOMEM;
521
522	/*
523	 * Let's populate it initially with (imperfect) reverse translation.
524	 * This is the next best thing we can do short of having it enabled
525	 * from the start even when no users rely on this functionality. True
526	 * unicode content will be available after a complete screen refresh.
527	 */
528	p = (unsigned short *)vc->vc_origin;
529	mask = vc->vc_hi_font_mask | 0xff;
530	for (y = 0; y < vc->vc_rows; y++) {
531		char32_t *line = uniscr->lines[y];
532		for (x = 0; x < vc->vc_cols; x++) {
533			u16 glyph = scr_readw(p++) & mask;
534			line[x] = inverse_translate(vc, glyph, true);
535		}
536	}
537
538	vc->vc_uni_screen = uniscr;
539	return 0;
540}
541
542/*
543 * Called from vcs_read() to get the unicode data from the screen.
544 * This must be preceded by a successful call to vc_uniscr_check() once
545 * the console lock has been taken.
546 */
547void vc_uniscr_copy_line(const struct vc_data *vc, void *dest, bool viewed,
548			 unsigned int row, unsigned int col, unsigned int nr)
549{
550	struct uni_screen *uniscr = get_vc_uniscr(vc);
551	int offset = row * vc->vc_size_row + col * 2;
552	unsigned long pos;
553
554	BUG_ON(!uniscr);
555
556	pos = (unsigned long)screenpos(vc, offset, viewed);
557	if (pos >= vc->vc_origin && pos < vc->vc_scr_end) {
558		/*
559		 * Desired position falls in the main screen buffer.
560		 * However the actual row/col might be different if
561		 * scrollback is active.
562		 */
563		row = (pos - vc->vc_origin) / vc->vc_size_row;
564		col = ((pos - vc->vc_origin) % vc->vc_size_row) / 2;
565		memcpy(dest, &uniscr->lines[row][col], nr * sizeof(char32_t));
566	} else {
567		/*
568		 * Scrollback is active. For now let's simply backtranslate
569		 * the screen glyphs until the unicode screen buffer does
570		 * synchronize with console display drivers for a scrollback
571		 * buffer of its own.
572		 */
573		u16 *p = (u16 *)pos;
574		int mask = vc->vc_hi_font_mask | 0xff;
575		char32_t *uni_buf = dest;
576		while (nr--) {
577			u16 glyph = scr_readw(p++) & mask;
578			*uni_buf++ = inverse_translate(vc, glyph, true);
579		}
580	}
581}
582
583/* this is for validation and debugging only */
584static void vc_uniscr_debug_check(struct vc_data *vc)
585{
586	struct uni_screen *uniscr = get_vc_uniscr(vc);
587	unsigned short *p;
588	int x, y, mask;
589
590	if (!VC_UNI_SCREEN_DEBUG || !uniscr)
591		return;
592
593	WARN_CONSOLE_UNLOCKED();
594
595	/*
596	 * Make sure our unicode screen translates into the same glyphs
597	 * as the actual screen. This is brutal indeed.
598	 */
599	p = (unsigned short *)vc->vc_origin;
600	mask = vc->vc_hi_font_mask | 0xff;
601	for (y = 0; y < vc->vc_rows; y++) {
602		char32_t *line = uniscr->lines[y];
603		for (x = 0; x < vc->vc_cols; x++) {
604			u16 glyph = scr_readw(p++) & mask;
605			char32_t uc = line[x];
606			int tc = conv_uni_to_pc(vc, uc);
607			if (tc == -4)
608				tc = conv_uni_to_pc(vc, 0xfffd);
609			if (tc == -4)
610				tc = conv_uni_to_pc(vc, '?');
611			if (tc != glyph)
612				pr_err_ratelimited(
613					"%s: mismatch at %d,%d: glyph=%#x tc=%#x\n",
614					__func__, x, y, glyph, tc);
615		}
616	}
617}
618
619
620static void con_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
621		enum con_scroll dir, unsigned int nr)
622{
623	u16 *clear, *d, *s;
624
625	if (t + nr >= b)
626		nr = b - t - 1;
627	if (b > vc->vc_rows || t >= b || nr < 1)
628		return;
629	vc_uniscr_scroll(vc, t, b, dir, nr);
630	if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, t, b, dir, nr))
631		return;
632
633	s = clear = (u16 *)(vc->vc_origin + vc->vc_size_row * t);
634	d = (u16 *)(vc->vc_origin + vc->vc_size_row * (t + nr));
635
636	if (dir == SM_UP) {
637		clear = s + (b - t - nr) * vc->vc_cols;
638		swap(s, d);
639	}
640	scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
641	scr_memsetw(clear, vc->vc_video_erase_char, vc->vc_size_row * nr);
642}
643
644static void do_update_region(struct vc_data *vc, unsigned long start, int count)
645{
646	unsigned int xx, yy, offset;
647	u16 *p;
648
649	p = (u16 *) start;
650	if (!vc->vc_sw->con_getxy) {
651		offset = (start - vc->vc_origin) / 2;
652		xx = offset % vc->vc_cols;
653		yy = offset / vc->vc_cols;
654	} else {
655		int nxx, nyy;
656		start = vc->vc_sw->con_getxy(vc, start, &nxx, &nyy);
657		xx = nxx; yy = nyy;
658	}
659	for(;;) {
660		u16 attrib = scr_readw(p) & 0xff00;
661		int startx = xx;
662		u16 *q = p;
663		while (xx < vc->vc_cols && count) {
664			if (attrib != (scr_readw(p) & 0xff00)) {
665				if (p > q)
666					vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
667				startx = xx;
668				q = p;
669				attrib = scr_readw(p) & 0xff00;
670			}
671			p++;
672			xx++;
673			count--;
674		}
675		if (p > q)
676			vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
677		if (!count)
678			break;
679		xx = 0;
680		yy++;
681		if (vc->vc_sw->con_getxy) {
682			p = (u16 *)start;
683			start = vc->vc_sw->con_getxy(vc, start, NULL, NULL);
684		}
685	}
686}
687
688void update_region(struct vc_data *vc, unsigned long start, int count)
689{
690	WARN_CONSOLE_UNLOCKED();
691
692	if (con_should_update(vc)) {
693		hide_cursor(vc);
694		do_update_region(vc, start, count);
695		set_cursor(vc);
696	}
697}
698
699/* Structure of attributes is hardware-dependent */
700
701static u8 build_attr(struct vc_data *vc, u8 _color,
702		enum vc_intensity _intensity, bool _blink, bool _underline,
703		bool _reverse, bool _italic)
704{
705	if (vc->vc_sw->con_build_attr)
706		return vc->vc_sw->con_build_attr(vc, _color, _intensity,
707		       _blink, _underline, _reverse, _italic);
708
709/*
710 * ++roman: I completely changed the attribute format for monochrome
711 * mode (!can_do_color). The formerly used MDA (monochrome display
712 * adapter) format didn't allow the combination of certain effects.
713 * Now the attribute is just a bit vector:
714 *  Bit 0..1: intensity (0..2)
715 *  Bit 2   : underline
716 *  Bit 3   : reverse
717 *  Bit 7   : blink
718 */
719	{
720	u8 a = _color;
721	if (!vc->vc_can_do_color)
722		return _intensity |
723		       (_italic    << 1) |
724		       (_underline << 2) |
725		       (_reverse   << 3) |
726		       (_blink     << 7);
727	if (_italic)
728		a = (a & 0xF0) | vc->vc_itcolor;
729	else if (_underline)
730		a = (a & 0xf0) | vc->vc_ulcolor;
731	else if (_intensity == VCI_HALF_BRIGHT)
732		a = (a & 0xf0) | vc->vc_halfcolor;
733	if (_reverse)
734		a = (a & 0x88) | (((a >> 4) | (a << 4)) & 0x77);
735	if (_blink)
736		a ^= 0x80;
737	if (_intensity == VCI_BOLD)
738		a ^= 0x08;
739	if (vc->vc_hi_font_mask == 0x100)
740		a <<= 1;
741	return a;
742	}
743}
744
745static void update_attr(struct vc_data *vc)
746{
747	vc->vc_attr = build_attr(vc, vc->state.color, vc->state.intensity,
748	              vc->state.blink, vc->state.underline,
749	              vc->state.reverse ^ vc->vc_decscnm, vc->state.italic);
750	vc->vc_video_erase_char = ' ' | (build_attr(vc, vc->state.color,
751				VCI_NORMAL, vc->state.blink, false,
752				vc->vc_decscnm, false) << 8);
753}
754
755/* Note: inverting the screen twice should revert to the original state */
756void invert_screen(struct vc_data *vc, int offset, int count, bool viewed)
757{
758	unsigned short *p;
759
760	WARN_CONSOLE_UNLOCKED();
761
762	count /= 2;
763	p = screenpos(vc, offset, viewed);
764	if (vc->vc_sw->con_invert_region) {
765		vc->vc_sw->con_invert_region(vc, p, count);
766	} else {
767		u16 *q = p;
768		int cnt = count;
769		u16 a;
770
771		if (!vc->vc_can_do_color) {
772			while (cnt--) {
773			    a = scr_readw(q);
774			    a ^= 0x0800;
775			    scr_writew(a, q);
776			    q++;
777			}
778		} else if (vc->vc_hi_font_mask == 0x100) {
779			while (cnt--) {
780				a = scr_readw(q);
781				a = (a & 0x11ff) |
782				   ((a & 0xe000) >> 4) |
783				   ((a & 0x0e00) << 4);
784				scr_writew(a, q);
785				q++;
786			}
787		} else {
788			while (cnt--) {
789				a = scr_readw(q);
790				a = (a & 0x88ff) |
791				   ((a & 0x7000) >> 4) |
792				   ((a & 0x0700) << 4);
793				scr_writew(a, q);
794				q++;
795			}
796		}
797	}
798
799	if (con_should_update(vc))
800		do_update_region(vc, (unsigned long) p, count);
801	notify_update(vc);
802}
803
804/* used by selection: complement pointer position */
805void complement_pos(struct vc_data *vc, int offset)
806{
807	static int old_offset = -1;
808	static unsigned short old;
809	static unsigned short oldx, oldy;
810
811	WARN_CONSOLE_UNLOCKED();
812
813	if (old_offset != -1 && old_offset >= 0 &&
814	    old_offset < vc->vc_screenbuf_size) {
815		scr_writew(old, screenpos(vc, old_offset, true));
816		if (con_should_update(vc))
817			vc->vc_sw->con_putc(vc, old, oldy, oldx);
818		notify_update(vc);
819	}
820
821	old_offset = offset;
822
823	if (offset != -1 && offset >= 0 &&
824	    offset < vc->vc_screenbuf_size) {
825		unsigned short new;
826		unsigned short *p;
827		p = screenpos(vc, offset, true);
828		old = scr_readw(p);
829		new = old ^ vc->vc_complement_mask;
830		scr_writew(new, p);
831		if (con_should_update(vc)) {
832			oldx = (offset >> 1) % vc->vc_cols;
833			oldy = (offset >> 1) / vc->vc_cols;
834			vc->vc_sw->con_putc(vc, new, oldy, oldx);
835		}
836		notify_update(vc);
837	}
838}
839
840static void insert_char(struct vc_data *vc, unsigned int nr)
841{
842	unsigned short *p = (unsigned short *) vc->vc_pos;
843
844	vc_uniscr_insert(vc, nr);
845	scr_memmovew(p + nr, p, (vc->vc_cols - vc->state.x - nr) * 2);
846	scr_memsetw(p, vc->vc_video_erase_char, nr * 2);
847	vc->vc_need_wrap = 0;
848	if (con_should_update(vc))
849		do_update_region(vc, (unsigned long) p,
850			vc->vc_cols - vc->state.x);
851}
852
853static void delete_char(struct vc_data *vc, unsigned int nr)
854{
855	unsigned short *p = (unsigned short *) vc->vc_pos;
856
857	vc_uniscr_delete(vc, nr);
858	scr_memmovew(p, p + nr, (vc->vc_cols - vc->state.x - nr) * 2);
859	scr_memsetw(p + vc->vc_cols - vc->state.x - nr, vc->vc_video_erase_char,
860			nr * 2);
861	vc->vc_need_wrap = 0;
862	if (con_should_update(vc))
863		do_update_region(vc, (unsigned long) p,
864			vc->vc_cols - vc->state.x);
865}
866
867static int softcursor_original = -1;
868
869static void add_softcursor(struct vc_data *vc)
870{
871	int i = scr_readw((u16 *) vc->vc_pos);
872	u32 type = vc->vc_cursor_type;
873
874	if (!(type & CUR_SW))
875		return;
876	if (softcursor_original != -1)
877		return;
878	softcursor_original = i;
879	i |= CUR_SET(type);
880	i ^= CUR_CHANGE(type);
881	if ((type & CUR_ALWAYS_BG) &&
882			(softcursor_original & CUR_BG) == (i & CUR_BG))
883		i ^= CUR_BG;
884	if ((type & CUR_INVERT_FG_BG) && (i & CUR_FG) == ((i & CUR_BG) >> 4))
885		i ^= CUR_FG;
886	scr_writew(i, (u16 *)vc->vc_pos);
887	if (con_should_update(vc))
888		vc->vc_sw->con_putc(vc, i, vc->state.y, vc->state.x);
889}
890
891static void hide_softcursor(struct vc_data *vc)
892{
893	if (softcursor_original != -1) {
894		scr_writew(softcursor_original, (u16 *)vc->vc_pos);
895		if (con_should_update(vc))
896			vc->vc_sw->con_putc(vc, softcursor_original,
897					vc->state.y, vc->state.x);
898		softcursor_original = -1;
899	}
900}
901
902static void hide_cursor(struct vc_data *vc)
903{
904	if (vc_is_sel(vc))
905		clear_selection();
906
907	vc->vc_sw->con_cursor(vc, CM_ERASE);
908	hide_softcursor(vc);
909}
910
911static void set_cursor(struct vc_data *vc)
912{
913	if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS)
914		return;
915	if (vc->vc_deccm) {
916		if (vc_is_sel(vc))
917			clear_selection();
918		add_softcursor(vc);
919		if (CUR_SIZE(vc->vc_cursor_type) != CUR_NONE)
920			vc->vc_sw->con_cursor(vc, CM_DRAW);
921	} else
922		hide_cursor(vc);
923}
924
925static void set_origin(struct vc_data *vc)
926{
927	WARN_CONSOLE_UNLOCKED();
928
929	if (!con_is_visible(vc) ||
930	    !vc->vc_sw->con_set_origin ||
931	    !vc->vc_sw->con_set_origin(vc))
932		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
933	vc->vc_visible_origin = vc->vc_origin;
934	vc->vc_scr_end = vc->vc_origin + vc->vc_screenbuf_size;
935	vc->vc_pos = vc->vc_origin + vc->vc_size_row * vc->state.y +
936		2 * vc->state.x;
937}
938
939static void save_screen(struct vc_data *vc)
940{
941	WARN_CONSOLE_UNLOCKED();
942
943	if (vc->vc_sw->con_save_screen)
944		vc->vc_sw->con_save_screen(vc);
945}
946
947static void flush_scrollback(struct vc_data *vc)
948{
949	WARN_CONSOLE_UNLOCKED();
950
951	set_origin(vc);
952	if (vc->vc_sw->con_flush_scrollback) {
953		vc->vc_sw->con_flush_scrollback(vc);
954	} else if (con_is_visible(vc)) {
955		/*
956		 * When no con_flush_scrollback method is provided then the
957		 * legacy way for flushing the scrollback buffer is to use
958		 * a side effect of the con_switch method. We do it only on
959		 * the foreground console as background consoles have no
960		 * scrollback buffers in that case and we obviously don't
961		 * want to switch to them.
962		 */
963		hide_cursor(vc);
964		vc->vc_sw->con_switch(vc);
965		set_cursor(vc);
966	}
967}
968
969/*
970 *	Redrawing of screen
971 */
972
973void clear_buffer_attributes(struct vc_data *vc)
974{
975	unsigned short *p = (unsigned short *)vc->vc_origin;
976	int count = vc->vc_screenbuf_size / 2;
977	int mask = vc->vc_hi_font_mask | 0xff;
978
979	for (; count > 0; count--, p++) {
980		scr_writew((scr_readw(p)&mask) | (vc->vc_video_erase_char & ~mask), p);
981	}
982}
983
984void redraw_screen(struct vc_data *vc, int is_switch)
985{
986	int redraw = 0;
987
988	WARN_CONSOLE_UNLOCKED();
989
990	if (!vc) {
991		/* strange ... */
992		/* printk("redraw_screen: tty %d not allocated ??\n", new_console+1); */
993		return;
994	}
995
996	if (is_switch) {
997		struct vc_data *old_vc = vc_cons[fg_console].d;
998		if (old_vc == vc)
999			return;
1000		if (!con_is_visible(vc))
1001			redraw = 1;
1002		*vc->vc_display_fg = vc;
1003		fg_console = vc->vc_num;
1004		hide_cursor(old_vc);
1005		if (!con_is_visible(old_vc)) {
1006			save_screen(old_vc);
1007			set_origin(old_vc);
1008		}
1009		if (tty0dev)
1010			sysfs_notify(&tty0dev->kobj, NULL, "active");
1011	} else {
1012		hide_cursor(vc);
1013		redraw = 1;
1014	}
1015
1016	if (redraw) {
1017		int update;
1018		int old_was_color = vc->vc_can_do_color;
1019
1020		set_origin(vc);
1021		update = vc->vc_sw->con_switch(vc);
1022		set_palette(vc);
1023		/*
1024		 * If console changed from mono<->color, the best we can do
1025		 * is to clear the buffer attributes. As it currently stands,
1026		 * rebuilding new attributes from the old buffer is not doable
1027		 * without overly complex code.
1028		 */
1029		if (old_was_color != vc->vc_can_do_color) {
1030			update_attr(vc);
1031			clear_buffer_attributes(vc);
1032		}
1033
1034		if (update && vc->vc_mode != KD_GRAPHICS)
1035			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
1036	}
1037	set_cursor(vc);
1038	if (is_switch) {
1039		set_leds();
1040		compute_shiftstate();
1041		notify_update(vc);
1042	}
1043}
1044
1045/*
1046 *	Allocation, freeing and resizing of VTs.
1047 */
1048
1049int vc_cons_allocated(unsigned int i)
1050{
1051	return (i < MAX_NR_CONSOLES && vc_cons[i].d);
1052}
1053
1054static void visual_init(struct vc_data *vc, int num, int init)
1055{
1056	/* ++Geert: vc->vc_sw->con_init determines console size */
1057	if (vc->vc_sw)
1058		module_put(vc->vc_sw->owner);
1059	vc->vc_sw = conswitchp;
1060#ifndef VT_SINGLE_DRIVER
1061	if (con_driver_map[num])
1062		vc->vc_sw = con_driver_map[num];
1063#endif
1064	__module_get(vc->vc_sw->owner);
1065	vc->vc_num = num;
1066	vc->vc_display_fg = &master_display_fg;
1067	if (vc->vc_uni_pagedir_loc)
1068		con_free_unimap(vc);
1069	vc->vc_uni_pagedir_loc = &vc->vc_uni_pagedir;
1070	vc->vc_uni_pagedir = NULL;
1071	vc->vc_hi_font_mask = 0;
1072	vc->vc_complement_mask = 0;
1073	vc->vc_can_do_color = 0;
1074	vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1075	vc->vc_sw->con_init(vc, init);
1076	if (!vc->vc_complement_mask)
1077		vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
1078	vc->vc_s_complement_mask = vc->vc_complement_mask;
1079	vc->vc_size_row = vc->vc_cols << 1;
1080	vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
1081}
1082
1083
1084static void visual_deinit(struct vc_data *vc)
1085{
1086	vc->vc_sw->con_deinit(vc);
1087	module_put(vc->vc_sw->owner);
1088}
1089
1090static void vc_port_destruct(struct tty_port *port)
1091{
1092	struct vc_data *vc = container_of(port, struct vc_data, port);
1093
1094	kfree(vc);
1095}
1096
1097static const struct tty_port_operations vc_port_ops = {
1098	.destruct = vc_port_destruct,
1099};
1100
1101/*
1102 * Change # of rows and columns (0 means unchanged/the size of fg_console)
1103 * [this is to be used together with some user program
1104 * like resize that changes the hardware videomode]
1105 */
1106#define VC_MAXCOL (32767)
1107#define VC_MAXROW (32767)
1108
1109int vc_allocate(unsigned int currcons)	/* return 0 on success */
1110{
1111	struct vt_notifier_param param;
1112	struct vc_data *vc;
1113	int err;
1114
1115	WARN_CONSOLE_UNLOCKED();
1116
1117	if (currcons >= MAX_NR_CONSOLES)
1118		return -ENXIO;
1119
1120	if (vc_cons[currcons].d)
1121		return 0;
1122
1123	/* due to the granularity of kmalloc, we waste some memory here */
1124	/* the alloc is done in two steps, to optimize the common situation
1125	   of a 25x80 console (structsize=216, screenbuf_size=4000) */
1126	/* although the numbers above are not valid since long ago, the
1127	   point is still up-to-date and the comment still has its value
1128	   even if only as a historical artifact.  --mj, July 1998 */
1129	param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL);
1130	if (!vc)
1131		return -ENOMEM;
1132
1133	vc_cons[currcons].d = vc;
1134	tty_port_init(&vc->port);
1135	vc->port.ops = &vc_port_ops;
1136	INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
1137
1138	visual_init(vc, currcons, 1);
1139
1140	if (!*vc->vc_uni_pagedir_loc)
1141		con_set_default_unimap(vc);
1142
1143	err = -EINVAL;
1144	if (vc->vc_cols > VC_MAXCOL || vc->vc_rows > VC_MAXROW ||
1145	    vc->vc_screenbuf_size > KMALLOC_MAX_SIZE || !vc->vc_screenbuf_size)
1146		goto err_free;
1147	err = -ENOMEM;
1148	vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
1149	if (!vc->vc_screenbuf)
1150		goto err_free;
1151
1152	/* If no drivers have overridden us and the user didn't pass a
1153	   boot option, default to displaying the cursor */
1154	if (global_cursor_default == -1)
1155		global_cursor_default = 1;
1156
1157	vc_init(vc, vc->vc_rows, vc->vc_cols, 1);
1158	vcs_make_sysfs(currcons);
1159	atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, &param);
1160
1161	return 0;
1162err_free:
1163	visual_deinit(vc);
1164	kfree(vc);
1165	vc_cons[currcons].d = NULL;
1166	return err;
1167}
1168
1169static inline int resize_screen(struct vc_data *vc, int width, int height,
1170				int user)
1171{
1172	/* Resizes the resolution of the display adapater */
1173	int err = 0;
1174
1175	if (vc->vc_sw->con_resize)
1176		err = vc->vc_sw->con_resize(vc, width, height, user);
1177
1178	return err;
1179}
1180
1181/**
1182 *	vc_do_resize	-	resizing method for the tty
1183 *	@tty: tty being resized
1184 *	@vc: virtual console private data
1185 *	@cols: columns
1186 *	@lines: lines
1187 *
1188 *	Resize a virtual console, clipping according to the actual constraints.
1189 *	If the caller passes a tty structure then update the termios winsize
1190 *	information and perform any necessary signal handling.
1191 *
1192 *	Caller must hold the console semaphore. Takes the termios rwsem and
1193 *	ctrl_lock of the tty IFF a tty is passed.
1194 */
1195
1196static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
1197				unsigned int cols, unsigned int lines)
1198{
1199	unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
1200	unsigned long end;
1201	unsigned int old_rows, old_row_size, first_copied_row;
1202	unsigned int new_cols, new_rows, new_row_size, new_screen_size;
1203	unsigned int user;
1204	unsigned short *oldscreen, *newscreen;
1205	struct uni_screen *new_uniscr = NULL;
1206
1207	WARN_CONSOLE_UNLOCKED();
1208
1209	if (!vc)
1210		return -ENXIO;
1211
1212	user = vc->vc_resize_user;
1213	vc->vc_resize_user = 0;
1214
1215	if (cols > VC_MAXCOL || lines > VC_MAXROW)
1216		return -EINVAL;
1217
1218	new_cols = (cols ? cols : vc->vc_cols);
1219	new_rows = (lines ? lines : vc->vc_rows);
1220	new_row_size = new_cols << 1;
1221	new_screen_size = new_row_size * new_rows;
1222
1223	if (new_cols == vc->vc_cols && new_rows == vc->vc_rows) {
1224		/*
1225		 * This function is being called here to cover the case
1226		 * where the userspace calls the FBIOPUT_VSCREENINFO twice,
1227		 * passing the same fb_var_screeninfo containing the fields
1228		 * yres/xres equal to a number non-multiple of vc_font.height
1229		 * and yres_virtual/xres_virtual equal to number lesser than the
1230		 * vc_font.height and yres/xres.
1231		 * In the second call, the struct fb_var_screeninfo isn't
1232		 * being modified by the underlying driver because of the
1233		 * if above, and this causes the fbcon_display->vrows to become
1234		 * negative and it eventually leads to out-of-bound
1235		 * access by the imageblit function.
1236		 * To give the correct values to the struct and to not have
1237		 * to deal with possible errors from the code below, we call
1238		 * the resize_screen here as well.
1239		 */
1240		return resize_screen(vc, new_cols, new_rows, user);
1241	}
1242
1243	if (new_screen_size > KMALLOC_MAX_SIZE || !new_screen_size)
1244		return -EINVAL;
1245	newscreen = kzalloc(new_screen_size, GFP_USER);
1246	if (!newscreen)
1247		return -ENOMEM;
1248
1249	if (get_vc_uniscr(vc)) {
1250		new_uniscr = vc_uniscr_alloc(new_cols, new_rows);
1251		if (!new_uniscr) {
1252			kfree(newscreen);
1253			return -ENOMEM;
1254		}
1255	}
1256
1257	if (vc_is_sel(vc))
1258		clear_selection();
1259
1260	old_rows = vc->vc_rows;
1261	old_row_size = vc->vc_size_row;
1262
1263	err = resize_screen(vc, new_cols, new_rows, user);
1264	if (err) {
1265		kfree(newscreen);
1266		vc_uniscr_free(new_uniscr);
1267		return err;
1268	}
1269
1270	vc->vc_rows = new_rows;
1271	vc->vc_cols = new_cols;
1272	vc->vc_size_row = new_row_size;
1273	vc->vc_screenbuf_size = new_screen_size;
1274
1275	rlth = min(old_row_size, new_row_size);
1276	rrem = new_row_size - rlth;
1277	old_origin = vc->vc_origin;
1278	new_origin = (long) newscreen;
1279	new_scr_end = new_origin + new_screen_size;
1280
1281	if (vc->state.y > new_rows) {
1282		if (old_rows - vc->state.y < new_rows) {
1283			/*
1284			 * Cursor near the bottom, copy contents from the
1285			 * bottom of buffer
1286			 */
1287			first_copied_row = (old_rows - new_rows);
1288		} else {
1289			/*
1290			 * Cursor is in no man's land, copy 1/2 screenful
1291			 * from the top and bottom of cursor position
1292			 */
1293			first_copied_row = (vc->state.y - new_rows/2);
1294		}
1295		old_origin += first_copied_row * old_row_size;
1296	} else
1297		first_copied_row = 0;
1298	end = old_origin + old_row_size * min(old_rows, new_rows);
1299
1300	vc_uniscr_copy_area(new_uniscr, new_cols, new_rows,
1301			    get_vc_uniscr(vc), rlth/2, first_copied_row,
1302			    min(old_rows, new_rows));
1303	vc_uniscr_set(vc, new_uniscr);
1304
1305	update_attr(vc);
1306
1307	while (old_origin < end) {
1308		scr_memcpyw((unsigned short *) new_origin,
1309			    (unsigned short *) old_origin, rlth);
1310		if (rrem)
1311			scr_memsetw((void *)(new_origin + rlth),
1312				    vc->vc_video_erase_char, rrem);
1313		old_origin += old_row_size;
1314		new_origin += new_row_size;
1315	}
1316	if (new_scr_end > new_origin)
1317		scr_memsetw((void *)new_origin, vc->vc_video_erase_char,
1318			    new_scr_end - new_origin);
1319	oldscreen = vc->vc_screenbuf;
1320	vc->vc_screenbuf = newscreen;
1321	vc->vc_screenbuf_size = new_screen_size;
1322	set_origin(vc);
1323	kfree(oldscreen);
1324
1325	/* do part of a reset_terminal() */
1326	vc->vc_top = 0;
1327	vc->vc_bottom = vc->vc_rows;
1328	gotoxy(vc, vc->state.x, vc->state.y);
1329	save_cur(vc);
1330
1331	if (tty) {
1332		/* Rewrite the requested winsize data with the actual
1333		   resulting sizes */
1334		struct winsize ws;
1335		memset(&ws, 0, sizeof(ws));
1336		ws.ws_row = vc->vc_rows;
1337		ws.ws_col = vc->vc_cols;
1338		ws.ws_ypixel = vc->vc_scan_lines;
1339		tty_do_resize(tty, &ws);
1340	}
1341
1342	if (con_is_visible(vc))
1343		update_screen(vc);
1344	vt_event_post(VT_EVENT_RESIZE, vc->vc_num, vc->vc_num);
1345	notify_update(vc);
1346	return err;
1347}
1348
1349/**
1350 *	vc_resize		-	resize a VT
1351 *	@vc: virtual console
1352 *	@cols: columns
1353 *	@rows: rows
1354 *
1355 *	Resize a virtual console as seen from the console end of things. We
1356 *	use the common vc_do_resize methods to update the structures. The
1357 *	caller must hold the console sem to protect console internals and
1358 *	vc->port.tty
1359 */
1360
1361int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
1362{
1363	return vc_do_resize(vc->port.tty, vc, cols, rows);
1364}
1365
1366/**
1367 *	vt_resize		-	resize a VT
1368 *	@tty: tty to resize
1369 *	@ws: winsize attributes
1370 *
1371 *	Resize a virtual terminal. This is called by the tty layer as we
1372 *	register our own handler for resizing. The mutual helper does all
1373 *	the actual work.
1374 *
1375 *	Takes the console sem and the called methods then take the tty
1376 *	termios_rwsem and the tty ctrl_lock in that order.
1377 */
1378static int vt_resize(struct tty_struct *tty, struct winsize *ws)
1379{
1380	struct vc_data *vc = tty->driver_data;
1381	int ret;
1382
1383	console_lock();
1384	ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row);
1385	console_unlock();
1386	return ret;
1387}
1388
1389struct vc_data *vc_deallocate(unsigned int currcons)
1390{
1391	struct vc_data *vc = NULL;
1392
1393	WARN_CONSOLE_UNLOCKED();
1394
1395	if (vc_cons_allocated(currcons)) {
1396		struct vt_notifier_param param;
1397
1398		param.vc = vc = vc_cons[currcons].d;
1399		atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, &param);
1400		vcs_remove_sysfs(currcons);
1401		visual_deinit(vc);
1402		con_free_unimap(vc);
1403		put_pid(vc->vt_pid);
1404		vc_uniscr_set(vc, NULL);
1405		kfree(vc->vc_screenbuf);
1406		vc_cons[currcons].d = NULL;
1407	}
1408	return vc;
1409}
1410
1411/*
1412 *	VT102 emulator
1413 */
1414
1415enum { EPecma = 0, EPdec, EPeq, EPgt, EPlt};
1416
1417#define set_kbd(vc, x)	vt_set_kbd_mode_bit((vc)->vc_num, (x))
1418#define clr_kbd(vc, x)	vt_clr_kbd_mode_bit((vc)->vc_num, (x))
1419#define is_kbd(vc, x)	vt_get_kbd_mode_bit((vc)->vc_num, (x))
1420
1421#define decarm		VC_REPEAT
1422#define decckm		VC_CKMODE
1423#define kbdapplic	VC_APPLIC
1424#define lnm		VC_CRLF
1425
1426const unsigned char color_table[] = { 0, 4, 2, 6, 1, 5, 3, 7,
1427				       8,12,10,14, 9,13,11,15 };
1428
1429/* the default colour table, for VGA+ colour systems */
1430unsigned char default_red[] = {
1431	0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa,
1432	0x55, 0xff, 0x55, 0xff, 0x55, 0xff, 0x55, 0xff
1433};
1434module_param_array(default_red, byte, NULL, S_IRUGO | S_IWUSR);
1435
1436unsigned char default_grn[] = {
1437	0x00, 0x00, 0xaa, 0x55, 0x00, 0x00, 0xaa, 0xaa,
1438	0x55, 0x55, 0xff, 0xff, 0x55, 0x55, 0xff, 0xff
1439};
1440module_param_array(default_grn, byte, NULL, S_IRUGO | S_IWUSR);
1441
1442unsigned char default_blu[] = {
1443	0x00, 0x00, 0x00, 0x00, 0xaa, 0xaa, 0xaa, 0xaa,
1444	0x55, 0x55, 0x55, 0x55, 0xff, 0xff, 0xff, 0xff
1445};
1446module_param_array(default_blu, byte, NULL, S_IRUGO | S_IWUSR);
1447
1448/*
1449 * gotoxy() must verify all boundaries, because the arguments
1450 * might also be negative. If the given position is out of
1451 * bounds, the cursor is placed at the nearest margin.
1452 */
1453static void gotoxy(struct vc_data *vc, int new_x, int new_y)
1454{
1455	int min_y, max_y;
1456
1457	if (new_x < 0)
1458		vc->state.x = 0;
1459	else {
1460		if (new_x >= vc->vc_cols)
1461			vc->state.x = vc->vc_cols - 1;
1462		else
1463			vc->state.x = new_x;
1464	}
1465
1466 	if (vc->vc_decom) {
1467		min_y = vc->vc_top;
1468		max_y = vc->vc_bottom;
1469	} else {
1470		min_y = 0;
1471		max_y = vc->vc_rows;
1472	}
1473	if (new_y < min_y)
1474		vc->state.y = min_y;
1475	else if (new_y >= max_y)
1476		vc->state.y = max_y - 1;
1477	else
1478		vc->state.y = new_y;
1479	vc->vc_pos = vc->vc_origin + vc->state.y * vc->vc_size_row +
1480		(vc->state.x << 1);
1481	vc->vc_need_wrap = 0;
1482}
1483
1484/* for absolute user moves, when decom is set */
1485static void gotoxay(struct vc_data *vc, int new_x, int new_y)
1486{
1487	gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y);
1488}
1489
1490void scrollback(struct vc_data *vc)
1491{
1492	scrolldelta(-(vc->vc_rows / 2));
1493}
1494
1495void scrollfront(struct vc_data *vc, int lines)
1496{
1497	if (!lines)
1498		lines = vc->vc_rows / 2;
1499	scrolldelta(lines);
1500}
1501
1502static void lf(struct vc_data *vc)
1503{
1504    	/* don't scroll if above bottom of scrolling region, or
1505	 * if below scrolling region
1506	 */
1507	if (vc->state.y + 1 == vc->vc_bottom)
1508		con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_UP, 1);
1509	else if (vc->state.y < vc->vc_rows - 1) {
1510		vc->state.y++;
1511		vc->vc_pos += vc->vc_size_row;
1512	}
1513	vc->vc_need_wrap = 0;
1514	notify_write(vc, '\n');
1515}
1516
1517static void ri(struct vc_data *vc)
1518{
1519    	/* don't scroll if below top of scrolling region, or
1520	 * if above scrolling region
1521	 */
1522	if (vc->state.y == vc->vc_top)
1523		con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_DOWN, 1);
1524	else if (vc->state.y > 0) {
1525		vc->state.y--;
1526		vc->vc_pos -= vc->vc_size_row;
1527	}
1528	vc->vc_need_wrap = 0;
1529}
1530
1531static inline void cr(struct vc_data *vc)
1532{
1533	vc->vc_pos -= vc->state.x << 1;
1534	vc->vc_need_wrap = vc->state.x = 0;
1535	notify_write(vc, '\r');
1536}
1537
1538static inline void bs(struct vc_data *vc)
1539{
1540	if (vc->state.x) {
1541		vc->vc_pos -= 2;
1542		vc->state.x--;
1543		vc->vc_need_wrap = 0;
1544		notify_write(vc, '\b');
1545	}
1546}
1547
1548static inline void del(struct vc_data *vc)
1549{
1550	/* ignored */
1551}
1552
1553static void csi_J(struct vc_data *vc, int vpar)
1554{
1555	unsigned int count;
1556	unsigned short * start;
1557
1558	switch (vpar) {
1559		case 0:	/* erase from cursor to end of display */
1560			vc_uniscr_clear_line(vc, vc->state.x,
1561					     vc->vc_cols - vc->state.x);
1562			vc_uniscr_clear_lines(vc, vc->state.y + 1,
1563					      vc->vc_rows - vc->state.y - 1);
1564			count = (vc->vc_scr_end - vc->vc_pos) >> 1;
1565			start = (unsigned short *)vc->vc_pos;
1566			break;
1567		case 1:	/* erase from start to cursor */
1568			vc_uniscr_clear_line(vc, 0, vc->state.x + 1);
1569			vc_uniscr_clear_lines(vc, 0, vc->state.y);
1570			count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1;
1571			start = (unsigned short *)vc->vc_origin;
1572			break;
1573		case 3: /* include scrollback */
1574			flush_scrollback(vc);
1575			fallthrough;
1576		case 2: /* erase whole display */
1577			vc_uniscr_clear_lines(vc, 0, vc->vc_rows);
1578			count = vc->vc_cols * vc->vc_rows;
1579			start = (unsigned short *)vc->vc_origin;
1580			break;
1581		default:
1582			return;
1583	}
1584	scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1585	if (con_should_update(vc))
1586		do_update_region(vc, (unsigned long) start, count);
1587	vc->vc_need_wrap = 0;
1588}
1589
1590static void csi_K(struct vc_data *vc, int vpar)
1591{
1592	unsigned int count;
1593	unsigned short *start = (unsigned short *)vc->vc_pos;
1594	int offset;
1595
1596	switch (vpar) {
1597		case 0:	/* erase from cursor to end of line */
1598			offset = 0;
1599			count = vc->vc_cols - vc->state.x;
1600			break;
1601		case 1:	/* erase from start of line to cursor */
1602			offset = -vc->state.x;
1603			count = vc->state.x + 1;
1604			break;
1605		case 2: /* erase whole line */
1606			offset = -vc->state.x;
1607			count = vc->vc_cols;
1608			break;
1609		default:
1610			return;
1611	}
1612	vc_uniscr_clear_line(vc, vc->state.x + offset, count);
1613	scr_memsetw(start + offset, vc->vc_video_erase_char, 2 * count);
1614	vc->vc_need_wrap = 0;
1615	if (con_should_update(vc))
1616		do_update_region(vc, (unsigned long)(start + offset), count);
1617}
1618
1619/* erase the following vpar positions */
1620static void csi_X(struct vc_data *vc, unsigned int vpar)
1621{					  /* not vt100? */
1622	unsigned int count;
1623
1624	if (!vpar)
1625		vpar++;
1626
1627	count = min(vpar, vc->vc_cols - vc->state.x);
1628
1629	vc_uniscr_clear_line(vc, vc->state.x, count);
1630	scr_memsetw((unsigned short *)vc->vc_pos, vc->vc_video_erase_char, 2 * count);
1631	if (con_should_update(vc))
1632		vc->vc_sw->con_clear(vc, vc->state.y, vc->state.x, 1, count);
1633	vc->vc_need_wrap = 0;
1634}
1635
1636static void default_attr(struct vc_data *vc)
1637{
1638	vc->state.intensity = VCI_NORMAL;
1639	vc->state.italic = false;
1640	vc->state.underline = false;
1641	vc->state.reverse = false;
1642	vc->state.blink = false;
1643	vc->state.color = vc->vc_def_color;
1644}
1645
1646struct rgb { u8 r; u8 g; u8 b; };
1647
1648static void rgb_from_256(int i, struct rgb *c)
1649{
1650	if (i < 8) {            /* Standard colours. */
1651		c->r = i&1 ? 0xaa : 0x00;
1652		c->g = i&2 ? 0xaa : 0x00;
1653		c->b = i&4 ? 0xaa : 0x00;
1654	} else if (i < 16) {
1655		c->r = i&1 ? 0xff : 0x55;
1656		c->g = i&2 ? 0xff : 0x55;
1657		c->b = i&4 ? 0xff : 0x55;
1658	} else if (i < 232) {   /* 6x6x6 colour cube. */
1659		c->r = (i - 16) / 36 * 85 / 2;
1660		c->g = (i - 16) / 6 % 6 * 85 / 2;
1661		c->b = (i - 16) % 6 * 85 / 2;
1662	} else                  /* Grayscale ramp. */
1663		c->r = c->g = c->b = i * 10 - 2312;
1664}
1665
1666static void rgb_foreground(struct vc_data *vc, const struct rgb *c)
1667{
1668	u8 hue = 0, max = max3(c->r, c->g, c->b);
1669
1670	if (c->r > max / 2)
1671		hue |= 4;
1672	if (c->g > max / 2)
1673		hue |= 2;
1674	if (c->b > max / 2)
1675		hue |= 1;
1676
1677	if (hue == 7 && max <= 0x55) {
1678		hue = 0;
1679		vc->state.intensity = VCI_BOLD;
1680	} else if (max > 0xaa)
1681		vc->state.intensity = VCI_BOLD;
1682	else
1683		vc->state.intensity = VCI_NORMAL;
1684
1685	vc->state.color = (vc->state.color & 0xf0) | hue;
1686}
1687
1688static void rgb_background(struct vc_data *vc, const struct rgb *c)
1689{
1690	/* For backgrounds, err on the dark side. */
1691	vc->state.color = (vc->state.color & 0x0f)
1692		| (c->r&0x80) >> 1 | (c->g&0x80) >> 2 | (c->b&0x80) >> 3;
1693}
1694
1695/*
1696 * ITU T.416 Higher colour modes. They break the usual properties of SGR codes
1697 * and thus need to be detected and ignored by hand. That standard also
1698 * wants : rather than ; as separators but sequences containing : are currently
1699 * completely ignored by the parser.
1700 *
1701 * Subcommands 3 (CMY) and 4 (CMYK) are so insane there's no point in
1702 * supporting them.
1703 */
1704static int vc_t416_color(struct vc_data *vc, int i,
1705		void(*set_color)(struct vc_data *vc, const struct rgb *c))
1706{
1707	struct rgb c;
1708
1709	i++;
1710	if (i > vc->vc_npar)
1711		return i;
1712
1713	if (vc->vc_par[i] == 5 && i + 1 <= vc->vc_npar) {
1714		/* 256 colours */
1715		i++;
1716		rgb_from_256(vc->vc_par[i], &c);
1717	} else if (vc->vc_par[i] == 2 && i + 3 <= vc->vc_npar) {
1718		/* 24 bit */
1719		c.r = vc->vc_par[i + 1];
1720		c.g = vc->vc_par[i + 2];
1721		c.b = vc->vc_par[i + 3];
1722		i += 3;
1723	} else
1724		return i;
1725
1726	set_color(vc, &c);
1727
1728	return i;
1729}
1730
1731/* console_lock is held */
1732static void csi_m(struct vc_data *vc)
1733{
1734	int i;
1735
1736	for (i = 0; i <= vc->vc_npar; i++)
1737		switch (vc->vc_par[i]) {
1738		case 0:	/* all attributes off */
1739			default_attr(vc);
1740			break;
1741		case 1:
1742			vc->state.intensity = VCI_BOLD;
1743			break;
1744		case 2:
1745			vc->state.intensity = VCI_HALF_BRIGHT;
1746			break;
1747		case 3:
1748			vc->state.italic = true;
1749			break;
1750		case 21:
1751			/*
1752			 * No console drivers support double underline, so
1753			 * convert it to a single underline.
1754			 */
1755		case 4:
1756			vc->state.underline = true;
1757			break;
1758		case 5:
1759			vc->state.blink = true;
1760			break;
1761		case 7:
1762			vc->state.reverse = true;
1763			break;
1764		case 10: /* ANSI X3.64-1979 (SCO-ish?)
1765			  * Select primary font, don't display control chars if
1766			  * defined, don't set bit 8 on output.
1767			  */
1768			vc->vc_translate = set_translate(vc->state.Gx_charset[vc->state.charset], vc);
1769			vc->vc_disp_ctrl = 0;
1770			vc->vc_toggle_meta = 0;
1771			break;
1772		case 11: /* ANSI X3.64-1979 (SCO-ish?)
1773			  * Select first alternate font, lets chars < 32 be
1774			  * displayed as ROM chars.
1775			  */
1776			vc->vc_translate = set_translate(IBMPC_MAP, vc);
1777			vc->vc_disp_ctrl = 1;
1778			vc->vc_toggle_meta = 0;
1779			break;
1780		case 12: /* ANSI X3.64-1979 (SCO-ish?)
1781			  * Select second alternate font, toggle high bit
1782			  * before displaying as ROM char.
1783			  */
1784			vc->vc_translate = set_translate(IBMPC_MAP, vc);
1785			vc->vc_disp_ctrl = 1;
1786			vc->vc_toggle_meta = 1;
1787			break;
1788		case 22:
1789			vc->state.intensity = VCI_NORMAL;
1790			break;
1791		case 23:
1792			vc->state.italic = false;
1793			break;
1794		case 24:
1795			vc->state.underline = false;
1796			break;
1797		case 25:
1798			vc->state.blink = false;
1799			break;
1800		case 27:
1801			vc->state.reverse = false;
1802			break;
1803		case 38:
1804			i = vc_t416_color(vc, i, rgb_foreground);
1805			break;
1806		case 48:
1807			i = vc_t416_color(vc, i, rgb_background);
1808			break;
1809		case 39:
1810			vc->state.color = (vc->vc_def_color & 0x0f) |
1811				(vc->state.color & 0xf0);
1812			break;
1813		case 49:
1814			vc->state.color = (vc->vc_def_color & 0xf0) |
1815				(vc->state.color & 0x0f);
1816			break;
1817		default:
1818			if (vc->vc_par[i] >= 90 && vc->vc_par[i] <= 107) {
1819				if (vc->vc_par[i] < 100)
1820					vc->state.intensity = VCI_BOLD;
1821				vc->vc_par[i] -= 60;
1822			}
1823			if (vc->vc_par[i] >= 30 && vc->vc_par[i] <= 37)
1824				vc->state.color = color_table[vc->vc_par[i] - 30]
1825					| (vc->state.color & 0xf0);
1826			else if (vc->vc_par[i] >= 40 && vc->vc_par[i] <= 47)
1827				vc->state.color = (color_table[vc->vc_par[i] - 40] << 4)
1828					| (vc->state.color & 0x0f);
1829			break;
1830		}
1831	update_attr(vc);
1832}
1833
1834static void respond_string(const char *p, size_t len, struct tty_port *port)
1835{
1836	tty_insert_flip_string(port, p, len);
1837	tty_flip_buffer_push(port);
1838}
1839
1840static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
1841{
1842	char buf[40];
1843	int len;
1844
1845	len = sprintf(buf, "\033[%d;%dR", vc->state.y +
1846			(vc->vc_decom ? vc->vc_top + 1 : 1),
1847			vc->state.x + 1);
1848	respond_string(buf, len, tty->port);
1849}
1850
1851static inline void status_report(struct tty_struct *tty)
1852{
1853	static const char teminal_ok[] = "\033[0n";
1854
1855	respond_string(teminal_ok, strlen(teminal_ok), tty->port);
1856}
1857
1858static inline void respond_ID(struct tty_struct *tty)
1859{
1860	/* terminal answer to an ESC-Z or csi0c query. */
1861	static const char vt102_id[] = "\033[?6c";
1862
1863	respond_string(vt102_id, strlen(vt102_id), tty->port);
1864}
1865
1866void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
1867{
1868	char buf[8];
1869	int len;
1870
1871	len = sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt),
1872			(char)('!' + mrx), (char)('!' + mry));
1873	respond_string(buf, len, tty->port);
1874}
1875
1876/* invoked via ioctl(TIOCLINUX) and through set_selection_user */
1877int mouse_reporting(void)
1878{
1879	return vc_cons[fg_console].d->vc_report_mouse;
1880}
1881
1882/* console_lock is held */
1883static void set_mode(struct vc_data *vc, int on_off)
1884{
1885	int i;
1886
1887	for (i = 0; i <= vc->vc_npar; i++)
1888		if (vc->vc_priv == EPdec) {
1889			switch(vc->vc_par[i]) {	/* DEC private modes set/reset */
1890			case 1:			/* Cursor keys send ^[Ox/^[[x */
1891				if (on_off)
1892					set_kbd(vc, decckm);
1893				else
1894					clr_kbd(vc, decckm);
1895				break;
1896			case 3:	/* 80/132 mode switch unimplemented */
1897#if 0
1898				vc_resize(deccolm ? 132 : 80, vc->vc_rows);
1899				/* this alone does not suffice; some user mode
1900				   utility has to change the hardware regs */
1901#endif
1902				break;
1903			case 5:			/* Inverted screen on/off */
1904				if (vc->vc_decscnm != on_off) {
1905					vc->vc_decscnm = on_off;
1906					invert_screen(vc, 0,
1907							vc->vc_screenbuf_size,
1908							false);
1909					update_attr(vc);
1910				}
1911				break;
1912			case 6:			/* Origin relative/absolute */
1913				vc->vc_decom = on_off;
1914				gotoxay(vc, 0, 0);
1915				break;
1916			case 7:			/* Autowrap on/off */
1917				vc->vc_decawm = on_off;
1918				break;
1919			case 8:			/* Autorepeat on/off */
1920				if (on_off)
1921					set_kbd(vc, decarm);
1922				else
1923					clr_kbd(vc, decarm);
1924				break;
1925			case 9:
1926				vc->vc_report_mouse = on_off ? 1 : 0;
1927				break;
1928			case 25:		/* Cursor on/off */
1929				vc->vc_deccm = on_off;
1930				break;
1931			case 1000:
1932				vc->vc_report_mouse = on_off ? 2 : 0;
1933				break;
1934			}
1935		} else {
1936			switch(vc->vc_par[i]) {	/* ANSI modes set/reset */
1937			case 3:			/* Monitor (display ctrls) */
1938				vc->vc_disp_ctrl = on_off;
1939				break;
1940			case 4:			/* Insert Mode on/off */
1941				vc->vc_decim = on_off;
1942				break;
1943			case 20:		/* Lf, Enter == CrLf/Lf */
1944				if (on_off)
1945					set_kbd(vc, lnm);
1946				else
1947					clr_kbd(vc, lnm);
1948				break;
1949			}
1950		}
1951}
1952
1953/* console_lock is held */
1954static void setterm_command(struct vc_data *vc)
1955{
1956	switch (vc->vc_par[0]) {
1957	case 1:	/* set color for underline mode */
1958		if (vc->vc_can_do_color && vc->vc_par[1] < 16) {
1959			vc->vc_ulcolor = color_table[vc->vc_par[1]];
1960			if (vc->state.underline)
1961				update_attr(vc);
1962		}
1963		break;
1964	case 2:	/* set color for half intensity mode */
1965		if (vc->vc_can_do_color && vc->vc_par[1] < 16) {
1966			vc->vc_halfcolor = color_table[vc->vc_par[1]];
1967			if (vc->state.intensity == VCI_HALF_BRIGHT)
1968				update_attr(vc);
1969		}
1970		break;
1971	case 8:	/* store colors as defaults */
1972		vc->vc_def_color = vc->vc_attr;
1973		if (vc->vc_hi_font_mask == 0x100)
1974			vc->vc_def_color >>= 1;
1975		default_attr(vc);
1976		update_attr(vc);
1977		break;
1978	case 9:	/* set blanking interval */
1979		blankinterval = min(vc->vc_par[1], 60U) * 60;
1980		poke_blanked_console();
1981		break;
1982	case 10: /* set bell frequency in Hz */
1983		if (vc->vc_npar >= 1)
1984			vc->vc_bell_pitch = vc->vc_par[1];
1985		else
1986			vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
1987		break;
1988	case 11: /* set bell duration in msec */
1989		if (vc->vc_npar >= 1)
1990			vc->vc_bell_duration = (vc->vc_par[1] < 2000) ?
1991				msecs_to_jiffies(vc->vc_par[1]) : 0;
1992		else
1993			vc->vc_bell_duration = DEFAULT_BELL_DURATION;
1994		break;
1995	case 12: /* bring specified console to the front */
1996		if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1))
1997			set_console(vc->vc_par[1] - 1);
1998		break;
1999	case 13: /* unblank the screen */
2000		poke_blanked_console();
2001		break;
2002	case 14: /* set vesa powerdown interval */
2003		vesa_off_interval = min(vc->vc_par[1], 60U) * 60 * HZ;
2004		break;
2005	case 15: /* activate the previous console */
2006		set_console(last_console);
2007		break;
2008	case 16: /* set cursor blink duration in msec */
2009		if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 &&
2010				vc->vc_par[1] <= USHRT_MAX)
2011			vc->vc_cur_blink_ms = vc->vc_par[1];
2012		else
2013			vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
2014		break;
2015	}
2016}
2017
2018/* console_lock is held */
2019static void csi_at(struct vc_data *vc, unsigned int nr)
2020{
2021	if (nr > vc->vc_cols - vc->state.x)
2022		nr = vc->vc_cols - vc->state.x;
2023	else if (!nr)
2024		nr = 1;
2025	insert_char(vc, nr);
2026}
2027
2028/* console_lock is held */
2029static void csi_L(struct vc_data *vc, unsigned int nr)
2030{
2031	if (nr > vc->vc_rows - vc->state.y)
2032		nr = vc->vc_rows - vc->state.y;
2033	else if (!nr)
2034		nr = 1;
2035	con_scroll(vc, vc->state.y, vc->vc_bottom, SM_DOWN, nr);
2036	vc->vc_need_wrap = 0;
2037}
2038
2039/* console_lock is held */
2040static void csi_P(struct vc_data *vc, unsigned int nr)
2041{
2042	if (nr > vc->vc_cols - vc->state.x)
2043		nr = vc->vc_cols - vc->state.x;
2044	else if (!nr)
2045		nr = 1;
2046	delete_char(vc, nr);
2047}
2048
2049/* console_lock is held */
2050static void csi_M(struct vc_data *vc, unsigned int nr)
2051{
2052	if (nr > vc->vc_rows - vc->state.y)
2053		nr = vc->vc_rows - vc->state.y;
2054	else if (!nr)
2055		nr=1;
2056	con_scroll(vc, vc->state.y, vc->vc_bottom, SM_UP, nr);
2057	vc->vc_need_wrap = 0;
2058}
2059
2060/* console_lock is held (except via vc_init->reset_terminal */
2061static void save_cur(struct vc_data *vc)
2062{
2063	memcpy(&vc->saved_state, &vc->state, sizeof(vc->state));
2064}
2065
2066/* console_lock is held */
2067static void restore_cur(struct vc_data *vc)
2068{
2069	memcpy(&vc->state, &vc->saved_state, sizeof(vc->state));
2070
2071	gotoxy(vc, vc->state.x, vc->state.y);
2072	vc->vc_translate = set_translate(vc->state.Gx_charset[vc->state.charset],
2073			vc);
2074	update_attr(vc);
2075	vc->vc_need_wrap = 0;
2076}
2077
2078enum { ESnormal, ESesc, ESsquare, ESgetpars, ESfunckey,
2079	EShash, ESsetG0, ESsetG1, ESpercent, EScsiignore, ESnonstd,
2080	ESpalette, ESosc, ESapc, ESpm, ESdcs };
2081
2082/* console_lock is held (except via vc_init()) */
2083static void reset_terminal(struct vc_data *vc, int do_clear)
2084{
2085	unsigned int i;
2086
2087	vc->vc_top		= 0;
2088	vc->vc_bottom		= vc->vc_rows;
2089	vc->vc_state		= ESnormal;
2090	vc->vc_priv		= EPecma;
2091	vc->vc_translate	= set_translate(LAT1_MAP, vc);
2092	vc->state.Gx_charset[0]	= LAT1_MAP;
2093	vc->state.Gx_charset[1]	= GRAF_MAP;
2094	vc->state.charset	= 0;
2095	vc->vc_need_wrap	= 0;
2096	vc->vc_report_mouse	= 0;
2097	vc->vc_utf              = default_utf8;
2098	vc->vc_utf_count	= 0;
2099
2100	vc->vc_disp_ctrl	= 0;
2101	vc->vc_toggle_meta	= 0;
2102
2103	vc->vc_decscnm		= 0;
2104	vc->vc_decom		= 0;
2105	vc->vc_decawm		= 1;
2106	vc->vc_deccm		= global_cursor_default;
2107	vc->vc_decim		= 0;
2108
2109	vt_reset_keyboard(vc->vc_num);
2110
2111	vc->vc_cursor_type = cur_default;
2112	vc->vc_complement_mask = vc->vc_s_complement_mask;
2113
2114	default_attr(vc);
2115	update_attr(vc);
2116
2117	bitmap_zero(vc->vc_tab_stop, VC_TABSTOPS_COUNT);
2118	for (i = 0; i < VC_TABSTOPS_COUNT; i += 8)
2119		set_bit(i, vc->vc_tab_stop);
2120
2121	vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
2122	vc->vc_bell_duration = DEFAULT_BELL_DURATION;
2123	vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
2124
2125	gotoxy(vc, 0, 0);
2126	save_cur(vc);
2127	if (do_clear)
2128	    csi_J(vc, 2);
2129}
2130
2131static void vc_setGx(struct vc_data *vc, unsigned int which, int c)
2132{
2133	unsigned char *charset = &vc->state.Gx_charset[which];
2134
2135	switch (c) {
2136	case '0':
2137		*charset = GRAF_MAP;
2138		break;
2139	case 'B':
2140		*charset = LAT1_MAP;
2141		break;
2142	case 'U':
2143		*charset = IBMPC_MAP;
2144		break;
2145	case 'K':
2146		*charset = USER_MAP;
2147		break;
2148	}
2149
2150	if (vc->state.charset == which)
2151		vc->vc_translate = set_translate(*charset, vc);
2152}
2153
2154/* is this state an ANSI control string? */
2155static bool ansi_control_string(unsigned int state)
2156{
2157	if (state == ESosc || state == ESapc || state == ESpm || state == ESdcs)
2158		return true;
2159	return false;
2160}
2161
2162/* console_lock is held */
2163static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
2164{
2165	/*
2166	 *  Control characters can be used in the _middle_
2167	 *  of an escape sequence, aside from ANSI control strings.
2168	 */
2169	if (ansi_control_string(vc->vc_state) && c >= 8 && c <= 13)
2170		return;
2171	switch (c) {
2172	case 0:
2173		return;
2174	case 7:
2175		if (ansi_control_string(vc->vc_state))
2176			vc->vc_state = ESnormal;
2177		else if (vc->vc_bell_duration)
2178			kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration);
2179		return;
2180	case 8:
2181		bs(vc);
2182		return;
2183	case 9:
2184		vc->vc_pos -= (vc->state.x << 1);
2185
2186		vc->state.x = find_next_bit(vc->vc_tab_stop,
2187				min(vc->vc_cols - 1, VC_TABSTOPS_COUNT),
2188				vc->state.x + 1);
2189		if (vc->state.x >= VC_TABSTOPS_COUNT)
2190			vc->state.x = vc->vc_cols - 1;
2191
2192		vc->vc_pos += (vc->state.x << 1);
2193		notify_write(vc, '\t');
2194		return;
2195	case 10: case 11: case 12:
2196		lf(vc);
2197		if (!is_kbd(vc, lnm))
2198			return;
2199		fallthrough;
2200	case 13:
2201		cr(vc);
2202		return;
2203	case 14:
2204		vc->state.charset = 1;
2205		vc->vc_translate = set_translate(vc->state.Gx_charset[1], vc);
2206		vc->vc_disp_ctrl = 1;
2207		return;
2208	case 15:
2209		vc->state.charset = 0;
2210		vc->vc_translate = set_translate(vc->state.Gx_charset[0], vc);
2211		vc->vc_disp_ctrl = 0;
2212		return;
2213	case 24: case 26:
2214		vc->vc_state = ESnormal;
2215		return;
2216	case 27:
2217		vc->vc_state = ESesc;
2218		return;
2219	case 127:
2220		del(vc);
2221		return;
2222	case 128+27:
2223		vc->vc_state = ESsquare;
2224		return;
2225	}
2226	switch(vc->vc_state) {
2227	case ESesc:
2228		vc->vc_state = ESnormal;
2229		switch (c) {
2230		case '[':
2231			vc->vc_state = ESsquare;
2232			return;
2233		case ']':
2234			vc->vc_state = ESnonstd;
2235			return;
2236		case '_':
2237			vc->vc_state = ESapc;
2238			return;
2239		case '^':
2240			vc->vc_state = ESpm;
2241			return;
2242		case '%':
2243			vc->vc_state = ESpercent;
2244			return;
2245		case 'E':
2246			cr(vc);
2247			lf(vc);
2248			return;
2249		case 'M':
2250			ri(vc);
2251			return;
2252		case 'D':
2253			lf(vc);
2254			return;
2255		case 'H':
2256			if (vc->state.x < VC_TABSTOPS_COUNT)
2257				set_bit(vc->state.x, vc->vc_tab_stop);
2258			return;
2259		case 'P':
2260			vc->vc_state = ESdcs;
2261			return;
2262		case 'Z':
2263			respond_ID(tty);
2264			return;
2265		case '7':
2266			save_cur(vc);
2267			return;
2268		case '8':
2269			restore_cur(vc);
2270			return;
2271		case '(':
2272			vc->vc_state = ESsetG0;
2273			return;
2274		case ')':
2275			vc->vc_state = ESsetG1;
2276			return;
2277		case '#':
2278			vc->vc_state = EShash;
2279			return;
2280		case 'c':
2281			reset_terminal(vc, 1);
2282			return;
2283		case '>':  /* Numeric keypad */
2284			clr_kbd(vc, kbdapplic);
2285			return;
2286		case '=':  /* Appl. keypad */
2287			set_kbd(vc, kbdapplic);
2288			return;
2289		}
2290		return;
2291	case ESnonstd:
2292		if (c=='P') {   /* palette escape sequence */
2293			for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2294				vc->vc_par[vc->vc_npar] = 0;
2295			vc->vc_npar = 0;
2296			vc->vc_state = ESpalette;
2297			return;
2298		} else if (c=='R') {   /* reset palette */
2299			reset_palette(vc);
2300			vc->vc_state = ESnormal;
2301		} else if (c>='0' && c<='9')
2302			vc->vc_state = ESosc;
2303		else
2304			vc->vc_state = ESnormal;
2305		return;
2306	case ESpalette:
2307		if (isxdigit(c)) {
2308			vc->vc_par[vc->vc_npar++] = hex_to_bin(c);
2309			if (vc->vc_npar == 7) {
2310				int i = vc->vc_par[0] * 3, j = 1;
2311				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2312				vc->vc_palette[i++] += vc->vc_par[j++];
2313				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2314				vc->vc_palette[i++] += vc->vc_par[j++];
2315				vc->vc_palette[i] = 16 * vc->vc_par[j++];
2316				vc->vc_palette[i] += vc->vc_par[j];
2317				set_palette(vc);
2318				vc->vc_state = ESnormal;
2319			}
2320		} else
2321			vc->vc_state = ESnormal;
2322		return;
2323	case ESsquare:
2324		for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2325			vc->vc_par[vc->vc_npar] = 0;
2326		vc->vc_npar = 0;
2327		vc->vc_state = ESgetpars;
2328		if (c == '[') { /* Function key */
2329			vc->vc_state=ESfunckey;
2330			return;
2331		}
2332		switch (c) {
2333		case '?':
2334			vc->vc_priv = EPdec;
2335			return;
2336		case '>':
2337			vc->vc_priv = EPgt;
2338			return;
2339		case '=':
2340			vc->vc_priv = EPeq;
2341			return;
2342		case '<':
2343			vc->vc_priv = EPlt;
2344			return;
2345		}
2346		vc->vc_priv = EPecma;
2347		fallthrough;
2348	case ESgetpars:
2349		if (c == ';' && vc->vc_npar < NPAR - 1) {
2350			vc->vc_npar++;
2351			return;
2352		} else if (c>='0' && c<='9') {
2353			vc->vc_par[vc->vc_npar] *= 10;
2354			vc->vc_par[vc->vc_npar] += c - '0';
2355			return;
2356		}
2357		if (c >= 0x20 && c <= 0x3f) { /* 0x2x, 0x3a and 0x3c - 0x3f */
2358			vc->vc_state = EScsiignore;
2359			return;
2360		}
2361		vc->vc_state = ESnormal;
2362		switch(c) {
2363		case 'h':
2364			if (vc->vc_priv <= EPdec)
2365				set_mode(vc, 1);
2366			return;
2367		case 'l':
2368			if (vc->vc_priv <= EPdec)
2369				set_mode(vc, 0);
2370			return;
2371		case 'c':
2372			if (vc->vc_priv == EPdec) {
2373				if (vc->vc_par[0])
2374					vc->vc_cursor_type =
2375						CUR_MAKE(vc->vc_par[0],
2376							 vc->vc_par[1],
2377							 vc->vc_par[2]);
2378				else
2379					vc->vc_cursor_type = cur_default;
2380				return;
2381			}
2382			break;
2383		case 'm':
2384			if (vc->vc_priv == EPdec) {
2385				clear_selection();
2386				if (vc->vc_par[0])
2387					vc->vc_complement_mask = vc->vc_par[0] << 8 | vc->vc_par[1];
2388				else
2389					vc->vc_complement_mask = vc->vc_s_complement_mask;
2390				return;
2391			}
2392			break;
2393		case 'n':
2394			if (vc->vc_priv == EPecma) {
2395				if (vc->vc_par[0] == 5)
2396					status_report(tty);
2397				else if (vc->vc_par[0] == 6)
2398					cursor_report(vc, tty);
2399			}
2400			return;
2401		}
2402		if (vc->vc_priv != EPecma) {
2403			vc->vc_priv = EPecma;
2404			return;
2405		}
2406		switch(c) {
2407		case 'G': case '`':
2408			if (vc->vc_par[0])
2409				vc->vc_par[0]--;
2410			gotoxy(vc, vc->vc_par[0], vc->state.y);
2411			return;
2412		case 'A':
2413			if (!vc->vc_par[0])
2414				vc->vc_par[0]++;
2415			gotoxy(vc, vc->state.x, vc->state.y - vc->vc_par[0]);
2416			return;
2417		case 'B': case 'e':
2418			if (!vc->vc_par[0])
2419				vc->vc_par[0]++;
2420			gotoxy(vc, vc->state.x, vc->state.y + vc->vc_par[0]);
2421			return;
2422		case 'C': case 'a':
2423			if (!vc->vc_par[0])
2424				vc->vc_par[0]++;
2425			gotoxy(vc, vc->state.x + vc->vc_par[0], vc->state.y);
2426			return;
2427		case 'D':
2428			if (!vc->vc_par[0])
2429				vc->vc_par[0]++;
2430			gotoxy(vc, vc->state.x - vc->vc_par[0], vc->state.y);
2431			return;
2432		case 'E':
2433			if (!vc->vc_par[0])
2434				vc->vc_par[0]++;
2435			gotoxy(vc, 0, vc->state.y + vc->vc_par[0]);
2436			return;
2437		case 'F':
2438			if (!vc->vc_par[0])
2439				vc->vc_par[0]++;
2440			gotoxy(vc, 0, vc->state.y - vc->vc_par[0]);
2441			return;
2442		case 'd':
2443			if (vc->vc_par[0])
2444				vc->vc_par[0]--;
2445			gotoxay(vc, vc->state.x ,vc->vc_par[0]);
2446			return;
2447		case 'H': case 'f':
2448			if (vc->vc_par[0])
2449				vc->vc_par[0]--;
2450			if (vc->vc_par[1])
2451				vc->vc_par[1]--;
2452			gotoxay(vc, vc->vc_par[1], vc->vc_par[0]);
2453			return;
2454		case 'J':
2455			csi_J(vc, vc->vc_par[0]);
2456			return;
2457		case 'K':
2458			csi_K(vc, vc->vc_par[0]);
2459			return;
2460		case 'L':
2461			csi_L(vc, vc->vc_par[0]);
2462			return;
2463		case 'M':
2464			csi_M(vc, vc->vc_par[0]);
2465			return;
2466		case 'P':
2467			csi_P(vc, vc->vc_par[0]);
2468			return;
2469		case 'c':
2470			if (!vc->vc_par[0])
2471				respond_ID(tty);
2472			return;
2473		case 'g':
2474			if (!vc->vc_par[0] && vc->state.x < VC_TABSTOPS_COUNT)
2475				set_bit(vc->state.x, vc->vc_tab_stop);
2476			else if (vc->vc_par[0] == 3)
2477				bitmap_zero(vc->vc_tab_stop, VC_TABSTOPS_COUNT);
2478			return;
2479		case 'm':
2480			csi_m(vc);
2481			return;
2482		case 'q': /* DECLL - but only 3 leds */
2483			/* map 0,1,2,3 to 0,1,2,4 */
2484			if (vc->vc_par[0] < 4)
2485				vt_set_led_state(vc->vc_num,
2486					    (vc->vc_par[0] < 3) ? vc->vc_par[0] : 4);
2487			return;
2488		case 'r':
2489			if (!vc->vc_par[0])
2490				vc->vc_par[0]++;
2491			if (!vc->vc_par[1])
2492				vc->vc_par[1] = vc->vc_rows;
2493			/* Minimum allowed region is 2 lines */
2494			if (vc->vc_par[0] < vc->vc_par[1] &&
2495			    vc->vc_par[1] <= vc->vc_rows) {
2496				vc->vc_top = vc->vc_par[0] - 1;
2497				vc->vc_bottom = vc->vc_par[1];
2498				gotoxay(vc, 0, 0);
2499			}
2500			return;
2501		case 's':
2502			save_cur(vc);
2503			return;
2504		case 'u':
2505			restore_cur(vc);
2506			return;
2507		case 'X':
2508			csi_X(vc, vc->vc_par[0]);
2509			return;
2510		case '@':
2511			csi_at(vc, vc->vc_par[0]);
2512			return;
2513		case ']': /* setterm functions */
2514			setterm_command(vc);
2515			return;
2516		}
2517		return;
2518	case EScsiignore:
2519		if (c >= 20 && c <= 0x3f)
2520			return;
2521		vc->vc_state = ESnormal;
2522		return;
2523	case ESpercent:
2524		vc->vc_state = ESnormal;
2525		switch (c) {
2526		case '@':  /* defined in ISO 2022 */
2527			vc->vc_utf = 0;
2528			return;
2529		case 'G':  /* prelim official escape code */
2530		case '8':  /* retained for compatibility */
2531			vc->vc_utf = 1;
2532			return;
2533		}
2534		return;
2535	case ESfunckey:
2536		vc->vc_state = ESnormal;
2537		return;
2538	case EShash:
2539		vc->vc_state = ESnormal;
2540		if (c == '8') {
2541			/* DEC screen alignment test. kludge :-) */
2542			vc->vc_video_erase_char =
2543				(vc->vc_video_erase_char & 0xff00) | 'E';
2544			csi_J(vc, 2);
2545			vc->vc_video_erase_char =
2546				(vc->vc_video_erase_char & 0xff00) | ' ';
2547			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
2548		}
2549		return;
2550	case ESsetG0:
2551		vc_setGx(vc, 0, c);
2552		vc->vc_state = ESnormal;
2553		return;
2554	case ESsetG1:
2555		vc_setGx(vc, 1, c);
2556		vc->vc_state = ESnormal;
2557		return;
2558	case ESapc:
2559		return;
2560	case ESosc:
2561		return;
2562	case ESpm:
2563		return;
2564	case ESdcs:
2565		return;
2566	default:
2567		vc->vc_state = ESnormal;
2568	}
2569}
2570
2571/* is_double_width() is based on the wcwidth() implementation by
2572 * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
2573 * Latest version: https://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
2574 */
2575struct interval {
2576	uint32_t first;
2577	uint32_t last;
2578};
2579
2580static int ucs_cmp(const void *key, const void *elt)
2581{
2582	uint32_t ucs = *(uint32_t *)key;
2583	struct interval e = *(struct interval *) elt;
2584
2585	if (ucs > e.last)
2586		return 1;
2587	else if (ucs < e.first)
2588		return -1;
2589	return 0;
2590}
2591
2592static int is_double_width(uint32_t ucs)
2593{
2594	static const struct interval double_width[] = {
2595		{ 0x1100, 0x115F }, { 0x2329, 0x232A }, { 0x2E80, 0x303E },
2596		{ 0x3040, 0xA4CF }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF },
2597		{ 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 },
2598		{ 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }
2599	};
2600	if (ucs < double_width[0].first ||
2601	    ucs > double_width[ARRAY_SIZE(double_width) - 1].last)
2602		return 0;
2603
2604	return bsearch(&ucs, double_width, ARRAY_SIZE(double_width),
2605			sizeof(struct interval), ucs_cmp) != NULL;
2606}
2607
2608struct vc_draw_region {
2609	unsigned long from, to;
2610	int x;
2611};
2612
2613static void con_flush(struct vc_data *vc, struct vc_draw_region *draw)
2614{
2615	if (draw->x < 0)
2616		return;
2617
2618	vc->vc_sw->con_putcs(vc, (u16 *)draw->from,
2619			(u16 *)draw->to - (u16 *)draw->from, vc->state.y,
2620			draw->x);
2621	draw->x = -1;
2622}
2623
2624static inline int vc_translate_ascii(const struct vc_data *vc, int c)
2625{
2626	if (IS_ENABLED(CONFIG_CONSOLE_TRANSLATIONS)) {
2627		if (vc->vc_toggle_meta)
2628			c |= 0x80;
2629
2630		return vc->vc_translate[c];
2631	}
2632
2633	return c;
2634}
2635
2636
2637/**
2638 * vc_sanitize_unicode -- Replace invalid Unicode code points with U+FFFD
2639 * @c: the received character, or U+FFFD for invalid sequences.
2640 */
2641static inline int vc_sanitize_unicode(const int c)
2642{
2643	if ((c >= 0xd800 && c <= 0xdfff) || c == 0xfffe || c == 0xffff)
2644		return 0xfffd;
2645
2646	return c;
2647}
2648
2649/**
2650 * vc_translate_unicode -- Combine UTF-8 into Unicode in @vc_utf_char
2651 * @vc: virtual console
2652 * @c: character to translate
2653 * @rescan: we return true if we need more (continuation) data
2654 *
2655 * @vc_utf_char is the being-constructed unicode character.
2656 * @vc_utf_count is the number of continuation bytes still expected to arrive.
2657 * @vc_npar is the number of continuation bytes arrived so far.
2658 */
2659static int vc_translate_unicode(struct vc_data *vc, int c, bool *rescan)
2660{
2661	static const u32 utf8_length_changes[] = {
2662		0x0000007f, 0x000007ff, 0x0000ffff,
2663		0x001fffff, 0x03ffffff, 0x7fffffff
2664	};
2665
2666	/* Continuation byte received */
2667	if ((c & 0xc0) == 0x80) {
2668		/* Unexpected continuation byte? */
2669		if (!vc->vc_utf_count)
2670			return 0xfffd;
2671
2672		vc->vc_utf_char = (vc->vc_utf_char << 6) | (c & 0x3f);
2673		vc->vc_npar++;
2674		if (--vc->vc_utf_count)
2675			goto need_more_bytes;
2676
2677		/* Got a whole character */
2678		c = vc->vc_utf_char;
2679		/* Reject overlong sequences */
2680		if (c <= utf8_length_changes[vc->vc_npar - 1] ||
2681				c > utf8_length_changes[vc->vc_npar])
2682			return 0xfffd;
2683
2684		return vc_sanitize_unicode(c);
2685	}
2686
2687	/* Single ASCII byte or first byte of a sequence received */
2688	if (vc->vc_utf_count) {
2689		/* Continuation byte expected */
2690		*rescan = true;
2691		vc->vc_utf_count = 0;
2692		return 0xfffd;
2693	}
2694
2695	/* Nothing to do if an ASCII byte was received */
2696	if (c <= 0x7f)
2697		return c;
2698
2699	/* First byte of a multibyte sequence received */
2700	vc->vc_npar = 0;
2701	if ((c & 0xe0) == 0xc0) {
2702		vc->vc_utf_count = 1;
2703		vc->vc_utf_char = (c & 0x1f);
2704	} else if ((c & 0xf0) == 0xe0) {
2705		vc->vc_utf_count = 2;
2706		vc->vc_utf_char = (c & 0x0f);
2707	} else if ((c & 0xf8) == 0xf0) {
2708		vc->vc_utf_count = 3;
2709		vc->vc_utf_char = (c & 0x07);
2710	} else if ((c & 0xfc) == 0xf8) {
2711		vc->vc_utf_count = 4;
2712		vc->vc_utf_char = (c & 0x03);
2713	} else if ((c & 0xfe) == 0xfc) {
2714		vc->vc_utf_count = 5;
2715		vc->vc_utf_char = (c & 0x01);
2716	} else {
2717		/* 254 and 255 are invalid */
2718		return 0xfffd;
2719	}
2720
2721need_more_bytes:
2722	return -1;
2723}
2724
2725static int vc_translate(struct vc_data *vc, int *c, bool *rescan)
2726{
2727	/* Do no translation at all in control states */
2728	if (vc->vc_state != ESnormal)
2729		return *c;
2730
2731	if (vc->vc_utf && !vc->vc_disp_ctrl)
2732		return *c = vc_translate_unicode(vc, *c, rescan);
2733
2734	/* no utf or alternate charset mode */
2735	return vc_translate_ascii(vc, *c);
2736}
2737
2738static inline unsigned char vc_invert_attr(const struct vc_data *vc)
2739{
2740	if (!vc->vc_can_do_color)
2741		return vc->vc_attr ^ 0x08;
2742
2743	if (vc->vc_hi_font_mask == 0x100)
2744		return   (vc->vc_attr & 0x11) |
2745			((vc->vc_attr & 0xe0) >> 4) |
2746			((vc->vc_attr & 0x0e) << 4);
2747
2748	return   (vc->vc_attr & 0x88) |
2749		((vc->vc_attr & 0x70) >> 4) |
2750		((vc->vc_attr & 0x07) << 4);
2751}
2752
2753static bool vc_is_control(struct vc_data *vc, int tc, int c)
2754{
2755	/*
2756	 * A bitmap for codes <32. A bit of 1 indicates that the code
2757	 * corresponding to that bit number invokes some special action (such
2758	 * as cursor movement) and should not be displayed as a glyph unless
2759	 * the disp_ctrl mode is explicitly enabled.
2760	 */
2761	static const u32 CTRL_ACTION = 0x0d00ff81;
2762	/* Cannot be overridden by disp_ctrl */
2763	static const u32 CTRL_ALWAYS = 0x0800f501;
2764
2765	if (vc->vc_state != ESnormal)
2766		return true;
2767
2768	if (!tc)
2769		return true;
2770
2771	/*
2772	 * If the original code was a control character we only allow a glyph
2773	 * to be displayed if the code is not normally used (such as for cursor
2774	 * movement) or if the disp_ctrl mode has been explicitly enabled.
2775	 * Certain characters (as given by the CTRL_ALWAYS bitmap) are always
2776	 * displayed as control characters, as the console would be pretty
2777	 * useless without them; to display an arbitrary font position use the
2778	 * direct-to-font zone in UTF-8 mode.
2779	 */
2780	if (c < 32) {
2781		if (vc->vc_disp_ctrl)
2782			return CTRL_ALWAYS & BIT(c);
2783		else
2784			return vc->vc_utf || (CTRL_ACTION & BIT(c));
2785	}
2786
2787	if (c == 127 && !vc->vc_disp_ctrl)
2788		return true;
2789
2790	if (c == 128 + 27)
2791		return true;
2792
2793	return false;
2794}
2795
2796static int vc_con_write_normal(struct vc_data *vc, int tc, int c,
2797		struct vc_draw_region *draw)
2798{
2799	int next_c;
2800	unsigned char vc_attr = vc->vc_attr;
2801	u16 himask = vc->vc_hi_font_mask, charmask = himask ? 0x1ff : 0xff;
2802	u8 width = 1;
2803	bool inverse = false;
2804
2805	if (vc->vc_utf && !vc->vc_disp_ctrl) {
2806		if (is_double_width(c))
2807			width = 2;
2808	}
2809
2810	/* Now try to find out how to display it */
2811	tc = conv_uni_to_pc(vc, tc);
2812	if (tc & ~charmask) {
2813		if (tc == -1 || tc == -2)
2814			return -1; /* nothing to display */
2815
2816		/* Glyph not found */
2817		if ((!vc->vc_utf || vc->vc_disp_ctrl || c < 128) &&
2818				!(c & ~charmask)) {
2819			/*
2820			 * In legacy mode use the glyph we get by a 1:1
2821			 * mapping.
2822			 * This would make absolutely no sense with Unicode in
2823			 * mind, but do this for ASCII characters since a font
2824			 * may lack Unicode mapping info and we don't want to
2825			 * end up with having question marks only.
2826			 */
2827			tc = c;
2828		} else {
2829			/*
2830			 * Display U+FFFD. If it's not found, display an inverse
2831			 * question mark.
2832			 */
2833			tc = conv_uni_to_pc(vc, 0xfffd);
2834			if (tc < 0) {
2835				inverse = true;
2836				tc = conv_uni_to_pc(vc, '?');
2837				if (tc < 0)
2838					tc = '?';
2839
2840				vc_attr = vc_invert_attr(vc);
2841				con_flush(vc, draw);
2842			}
2843		}
2844	}
2845
2846	next_c = c;
2847	while (1) {
2848		if (vc->vc_need_wrap || vc->vc_decim)
2849			con_flush(vc, draw);
2850		if (vc->vc_need_wrap) {
2851			cr(vc);
2852			lf(vc);
2853		}
2854		if (vc->vc_decim)
2855			insert_char(vc, 1);
2856		vc_uniscr_putc(vc, next_c);
2857
2858		if (himask)
2859			tc = ((tc & 0x100) ? himask : 0) |
2860			      (tc &  0xff);
2861		tc |= (vc_attr << 8) & ~himask;
2862
2863		scr_writew(tc, (u16 *)vc->vc_pos);
2864
2865		if (con_should_update(vc) && draw->x < 0) {
2866			draw->x = vc->state.x;
2867			draw->from = vc->vc_pos;
2868		}
2869		if (vc->state.x == vc->vc_cols - 1) {
2870			vc->vc_need_wrap = vc->vc_decawm;
2871			draw->to = vc->vc_pos + 2;
2872		} else {
2873			vc->state.x++;
2874			draw->to = (vc->vc_pos += 2);
2875		}
2876
2877		if (!--width)
2878			break;
2879
2880		/* A space is printed in the second column */
2881		tc = conv_uni_to_pc(vc, ' ');
2882		if (tc < 0)
2883			tc = ' ';
2884		next_c = ' ';
2885	}
2886	notify_write(vc, c);
2887
2888	if (inverse)
2889		con_flush(vc, draw);
2890
2891	return 0;
2892}
2893
2894/* acquires console_lock */
2895static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int count)
2896{
2897	struct vc_draw_region draw = {
2898		.x = -1,
2899	};
2900	int c, tc, n = 0;
2901	unsigned int currcons;
2902	struct vc_data *vc;
2903	struct vt_notifier_param param;
2904	bool rescan;
2905
2906	if (in_interrupt())
2907		return count;
2908
2909	console_lock();
2910	vc = tty->driver_data;
2911	if (vc == NULL) {
2912		pr_err("vt: argh, driver_data is NULL !\n");
2913		console_unlock();
2914		return 0;
2915	}
2916
2917	currcons = vc->vc_num;
2918	if (!vc_cons_allocated(currcons)) {
2919		/* could this happen? */
2920		pr_warn_once("con_write: tty %d not allocated\n", currcons+1);
2921		console_unlock();
2922		return 0;
2923	}
2924
2925
2926	/* undraw cursor first */
2927	if (con_is_fg(vc))
2928		hide_cursor(vc);
2929
2930	param.vc = vc;
2931
2932	while (!tty->stopped && count) {
2933		int orig = *buf;
2934		buf++;
2935		n++;
2936		count--;
2937rescan_last_byte:
2938		c = orig;
2939		rescan = false;
2940
2941		tc = vc_translate(vc, &c, &rescan);
2942		if (tc == -1)
2943			continue;
2944
2945		param.c = tc;
2946		if (atomic_notifier_call_chain(&vt_notifier_list, VT_PREWRITE,
2947					&param) == NOTIFY_STOP)
2948			continue;
2949
2950		if (vc_is_control(vc, tc, c)) {
2951			con_flush(vc, &draw);
2952			do_con_trol(tty, vc, orig);
2953			continue;
2954		}
2955
2956		if (vc_con_write_normal(vc, tc, c, &draw) < 0)
2957			continue;
2958
2959		if (rescan)
2960			goto rescan_last_byte;
2961	}
2962	con_flush(vc, &draw);
2963	vc_uniscr_debug_check(vc);
2964	console_conditional_schedule();
2965	notify_update(vc);
2966	console_unlock();
2967	return n;
2968}
2969
2970/*
2971 * This is the console switching callback.
2972 *
2973 * Doing console switching in a process context allows
2974 * us to do the switches asynchronously (needed when we want
2975 * to switch due to a keyboard interrupt).  Synchronization
2976 * with other console code and prevention of re-entrancy is
2977 * ensured with console_lock.
2978 */
2979static void console_callback(struct work_struct *ignored)
2980{
2981	console_lock();
2982
2983	if (want_console >= 0) {
2984		if (want_console != fg_console &&
2985		    vc_cons_allocated(want_console)) {
2986			hide_cursor(vc_cons[fg_console].d);
2987			change_console(vc_cons[want_console].d);
2988			/* we only changed when the console had already
2989			   been allocated - a new console is not created
2990			   in an interrupt routine */
2991		}
2992		want_console = -1;
2993	}
2994	if (do_poke_blanked_console) { /* do not unblank for a LED change */
2995		do_poke_blanked_console = 0;
2996		poke_blanked_console();
2997	}
2998	if (scrollback_delta) {
2999		struct vc_data *vc = vc_cons[fg_console].d;
3000		clear_selection();
3001		if (vc->vc_mode == KD_TEXT && vc->vc_sw->con_scrolldelta)
3002			vc->vc_sw->con_scrolldelta(vc, scrollback_delta);
3003		scrollback_delta = 0;
3004	}
3005	if (blank_timer_expired) {
3006		do_blank_screen(0);
3007		blank_timer_expired = 0;
3008	}
3009	notify_update(vc_cons[fg_console].d);
3010
3011	console_unlock();
3012}
3013
3014int set_console(int nr)
3015{
3016	struct vc_data *vc = vc_cons[fg_console].d;
3017
3018	if (!vc_cons_allocated(nr) || vt_dont_switch ||
3019		(vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) {
3020
3021		/*
3022		 * Console switch will fail in console_callback() or
3023		 * change_console() so there is no point scheduling
3024		 * the callback
3025		 *
3026		 * Existing set_console() users don't check the return
3027		 * value so this shouldn't break anything
3028		 */
3029		return -EINVAL;
3030	}
3031
3032	want_console = nr;
3033	schedule_console_callback();
3034
3035	return 0;
3036}
3037
3038struct tty_driver *console_driver;
3039
3040#ifdef CONFIG_VT_CONSOLE
3041
3042/**
3043 * vt_kmsg_redirect() - Sets/gets the kernel message console
3044 * @new:	The new virtual terminal number or -1 if the console should stay
3045 * 		unchanged
3046 *
3047 * By default, the kernel messages are always printed on the current virtual
3048 * console. However, the user may modify that default with the
3049 * TIOCL_SETKMSGREDIRECT ioctl call.
3050 *
3051 * This function sets the kernel message console to be @new. It returns the old
3052 * virtual console number. The virtual terminal number 0 (both as parameter and
3053 * return value) means no redirection (i.e. always printed on the currently
3054 * active console).
3055 *
3056 * The parameter -1 means that only the current console is returned, but the
3057 * value is not modified. You may use the macro vt_get_kmsg_redirect() in that
3058 * case to make the code more understandable.
3059 *
3060 * When the kernel is compiled without CONFIG_VT_CONSOLE, this function ignores
3061 * the parameter and always returns 0.
3062 */
3063int vt_kmsg_redirect(int new)
3064{
3065	static int kmsg_con;
3066
3067	if (new != -1)
3068		return xchg(&kmsg_con, new);
3069	else
3070		return kmsg_con;
3071}
3072
3073/*
3074 *	Console on virtual terminal
3075 *
3076 * The console must be locked when we get here.
3077 */
3078
3079static void vt_console_print(struct console *co, const char *b, unsigned count)
3080{
3081	struct vc_data *vc = vc_cons[fg_console].d;
3082	unsigned char c;
3083	static DEFINE_SPINLOCK(printing_lock);
3084	const ushort *start;
3085	ushort start_x, cnt;
3086	int kmsg_console;
3087
3088	/* console busy or not yet initialized */
3089	if (!printable)
3090		return;
3091	if (!spin_trylock(&printing_lock))
3092		return;
3093
3094	kmsg_console = vt_get_kmsg_redirect();
3095	if (kmsg_console && vc_cons_allocated(kmsg_console - 1))
3096		vc = vc_cons[kmsg_console - 1].d;
3097
3098	if (!vc_cons_allocated(fg_console)) {
3099		/* impossible */
3100		/* printk("vt_console_print: tty %d not allocated ??\n", currcons+1); */
3101		goto quit;
3102	}
3103
3104	if (vc->vc_mode != KD_TEXT)
3105		goto quit;
3106
3107	/* undraw cursor first */
3108	if (con_is_fg(vc))
3109		hide_cursor(vc);
3110
3111	start = (ushort *)vc->vc_pos;
3112	start_x = vc->state.x;
3113	cnt = 0;
3114	while (count--) {
3115		c = *b++;
3116		if (c == 10 || c == 13 || c == 8 || vc->vc_need_wrap) {
3117			if (cnt && con_is_visible(vc))
3118				vc->vc_sw->con_putcs(vc, start, cnt, vc->state.y, start_x);
3119			cnt = 0;
3120			if (c == 8) {		/* backspace */
3121				bs(vc);
3122				start = (ushort *)vc->vc_pos;
3123				start_x = vc->state.x;
3124				continue;
3125			}
3126			if (c != 13)
3127				lf(vc);
3128			cr(vc);
3129			start = (ushort *)vc->vc_pos;
3130			start_x = vc->state.x;
3131			if (c == 10 || c == 13)
3132				continue;
3133		}
3134		vc_uniscr_putc(vc, c);
3135		scr_writew((vc->vc_attr << 8) + c, (unsigned short *)vc->vc_pos);
3136		notify_write(vc, c);
3137		cnt++;
3138		if (vc->state.x == vc->vc_cols - 1) {
3139			vc->vc_need_wrap = 1;
3140		} else {
3141			vc->vc_pos += 2;
3142			vc->state.x++;
3143		}
3144	}
3145	if (cnt && con_is_visible(vc))
3146		vc->vc_sw->con_putcs(vc, start, cnt, vc->state.y, start_x);
3147	set_cursor(vc);
3148	notify_update(vc);
3149
3150quit:
3151	spin_unlock(&printing_lock);
3152}
3153
3154static struct tty_driver *vt_console_device(struct console *c, int *index)
3155{
3156	*index = c->index ? c->index-1 : fg_console;
3157	return console_driver;
3158}
3159
3160static struct console vt_console_driver = {
3161	.name		= "tty",
3162	.write		= vt_console_print,
3163	.device		= vt_console_device,
3164	.unblank	= unblank_screen,
3165	.flags		= CON_PRINTBUFFER,
3166	.index		= -1,
3167};
3168#endif
3169
3170/*
3171 *	Handling of Linux-specific VC ioctls
3172 */
3173
3174/*
3175 * Generally a bit racy with respect to console_lock();.
3176 *
3177 * There are some functions which don't need it.
3178 *
3179 * There are some functions which can sleep for arbitrary periods
3180 * (paste_selection) but we don't need the lock there anyway.
3181 *
3182 * set_selection_user has locking, and definitely needs it
3183 */
3184
3185int tioclinux(struct tty_struct *tty, unsigned long arg)
3186{
3187	char type, data;
3188	char __user *p = (char __user *)arg;
3189	int lines;
3190	int ret;
3191
3192	if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
3193		return -EPERM;
3194	if (get_user(type, p))
3195		return -EFAULT;
3196	ret = 0;
3197
3198	switch (type)
3199	{
3200		case TIOCL_SETSEL:
3201			ret = set_selection_user((struct tiocl_selection
3202						 __user *)(p+1), tty);
3203			break;
3204		case TIOCL_PASTESEL:
3205			ret = paste_selection(tty);
3206			break;
3207		case TIOCL_UNBLANKSCREEN:
3208			console_lock();
3209			unblank_screen();
3210			console_unlock();
3211			break;
3212		case TIOCL_SELLOADLUT:
3213			console_lock();
3214			ret = sel_loadlut(p);
3215			console_unlock();
3216			break;
3217		case TIOCL_GETSHIFTSTATE:
3218
3219	/*
3220	 * Make it possible to react to Shift+Mousebutton.
3221	 * Note that 'shift_state' is an undocumented
3222	 * kernel-internal variable; programs not closely
3223	 * related to the kernel should not use this.
3224	 */
3225			data = vt_get_shift_state();
3226			ret = put_user(data, p);
3227			break;
3228		case TIOCL_GETMOUSEREPORTING:
3229			console_lock();	/* May be overkill */
3230			data = mouse_reporting();
3231			console_unlock();
3232			ret = put_user(data, p);
3233			break;
3234		case TIOCL_SETVESABLANK:
3235			console_lock();
3236			ret = set_vesa_blanking(p);
3237			console_unlock();
3238			break;
3239		case TIOCL_GETKMSGREDIRECT:
3240			data = vt_get_kmsg_redirect();
3241			ret = put_user(data, p);
3242			break;
3243		case TIOCL_SETKMSGREDIRECT:
3244			if (!capable(CAP_SYS_ADMIN)) {
3245				ret = -EPERM;
3246			} else {
3247				if (get_user(data, p+1))
3248					ret = -EFAULT;
3249				else
3250					vt_kmsg_redirect(data);
3251			}
3252			break;
3253		case TIOCL_GETFGCONSOLE:
3254			/* No locking needed as this is a transiently
3255			   correct return anyway if the caller hasn't
3256			   disabled switching */
3257			ret = fg_console;
3258			break;
3259		case TIOCL_SCROLLCONSOLE:
3260			if (get_user(lines, (s32 __user *)(p+4))) {
3261				ret = -EFAULT;
3262			} else {
3263				/* Need the console lock here. Note that lots
3264				   of other calls need fixing before the lock
3265				   is actually useful ! */
3266				console_lock();
3267				scrollfront(vc_cons[fg_console].d, lines);
3268				console_unlock();
3269				ret = 0;
3270			}
3271			break;
3272		case TIOCL_BLANKSCREEN:	/* until explicitly unblanked, not only poked */
3273			console_lock();
3274			ignore_poke = 1;
3275			do_blank_screen(0);
3276			console_unlock();
3277			break;
3278		case TIOCL_BLANKEDSCREEN:
3279			ret = console_blanked;
3280			break;
3281		default:
3282			ret = -EINVAL;
3283			break;
3284	}
3285	return ret;
3286}
3287
3288/*
3289 * /dev/ttyN handling
3290 */
3291
3292static int con_write(struct tty_struct *tty, const unsigned char *buf, int count)
3293{
3294	int	retval;
3295
3296	retval = do_con_write(tty, buf, count);
3297	con_flush_chars(tty);
3298
3299	return retval;
3300}
3301
3302static int con_put_char(struct tty_struct *tty, unsigned char ch)
3303{
3304	if (in_interrupt())
3305		return 0;	/* n_r3964 calls put_char() from interrupt context */
3306	return do_con_write(tty, &ch, 1);
3307}
3308
3309static int con_write_room(struct tty_struct *tty)
3310{
3311	if (tty->stopped)
3312		return 0;
3313	return 32768;		/* No limit, really; we're not buffering */
3314}
3315
3316static int con_chars_in_buffer(struct tty_struct *tty)
3317{
3318	return 0;		/* we're not buffering */
3319}
3320
3321/*
3322 * con_throttle and con_unthrottle are only used for
3323 * paste_selection(), which has to stuff in a large number of
3324 * characters...
3325 */
3326static void con_throttle(struct tty_struct *tty)
3327{
3328}
3329
3330static void con_unthrottle(struct tty_struct *tty)
3331{
3332	struct vc_data *vc = tty->driver_data;
3333
3334	wake_up_interruptible(&vc->paste_wait);
3335}
3336
3337/*
3338 * Turn the Scroll-Lock LED on when the tty is stopped
3339 */
3340static void con_stop(struct tty_struct *tty)
3341{
3342	int console_num;
3343	if (!tty)
3344		return;
3345	console_num = tty->index;
3346	if (!vc_cons_allocated(console_num))
3347		return;
3348	vt_kbd_con_stop(console_num);
3349}
3350
3351/*
3352 * Turn the Scroll-Lock LED off when the console is started
3353 */
3354static void con_start(struct tty_struct *tty)
3355{
3356	int console_num;
3357	if (!tty)
3358		return;
3359	console_num = tty->index;
3360	if (!vc_cons_allocated(console_num))
3361		return;
3362	vt_kbd_con_start(console_num);
3363}
3364
3365static void con_flush_chars(struct tty_struct *tty)
3366{
3367	struct vc_data *vc;
3368
3369	if (in_interrupt())	/* from flush_to_ldisc */
3370		return;
3371
3372	/* if we race with con_close(), vt may be null */
3373	console_lock();
3374	vc = tty->driver_data;
3375	if (vc)
3376		set_cursor(vc);
3377	console_unlock();
3378}
3379
3380/*
3381 * Allocate the console screen memory.
3382 */
3383static int con_install(struct tty_driver *driver, struct tty_struct *tty)
3384{
3385	unsigned int currcons = tty->index;
3386	struct vc_data *vc;
3387	int ret;
3388
3389	console_lock();
3390	ret = vc_allocate(currcons);
3391	if (ret)
3392		goto unlock;
3393
3394	vc = vc_cons[currcons].d;
3395
3396	/* Still being freed */
3397	if (vc->port.tty) {
3398		ret = -ERESTARTSYS;
3399		goto unlock;
3400	}
3401
3402	ret = tty_port_install(&vc->port, driver, tty);
3403	if (ret)
3404		goto unlock;
3405
3406	tty->driver_data = vc;
3407	vc->port.tty = tty;
3408	tty_port_get(&vc->port);
3409
3410	if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
3411		tty->winsize.ws_row = vc_cons[currcons].d->vc_rows;
3412		tty->winsize.ws_col = vc_cons[currcons].d->vc_cols;
3413	}
3414	if (vc->vc_utf)
3415		tty->termios.c_iflag |= IUTF8;
3416	else
3417		tty->termios.c_iflag &= ~IUTF8;
3418unlock:
3419	console_unlock();
3420	return ret;
3421}
3422
3423static int con_open(struct tty_struct *tty, struct file *filp)
3424{
3425	/* everything done in install */
3426	return 0;
3427}
3428
3429
3430static void con_close(struct tty_struct *tty, struct file *filp)
3431{
3432	/* Nothing to do - we defer to shutdown */
3433}
3434
3435static void con_shutdown(struct tty_struct *tty)
3436{
3437	struct vc_data *vc = tty->driver_data;
3438	BUG_ON(vc == NULL);
3439	console_lock();
3440	vc->port.tty = NULL;
3441	console_unlock();
3442}
3443
3444static void con_cleanup(struct tty_struct *tty)
3445{
3446	struct vc_data *vc = tty->driver_data;
3447
3448	tty_port_put(&vc->port);
3449}
3450
3451static int default_color           = 7; /* white */
3452static int default_italic_color    = 2; // green (ASCII)
3453static int default_underline_color = 3; // cyan (ASCII)
3454module_param_named(color, default_color, int, S_IRUGO | S_IWUSR);
3455module_param_named(italic, default_italic_color, int, S_IRUGO | S_IWUSR);
3456module_param_named(underline, default_underline_color, int, S_IRUGO | S_IWUSR);
3457
3458static void vc_init(struct vc_data *vc, unsigned int rows,
3459		    unsigned int cols, int do_clear)
3460{
3461	int j, k ;
3462
3463	vc->vc_cols = cols;
3464	vc->vc_rows = rows;
3465	vc->vc_size_row = cols << 1;
3466	vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
3467
3468	set_origin(vc);
3469	vc->vc_pos = vc->vc_origin;
3470	reset_vc(vc);
3471	for (j=k=0; j<16; j++) {
3472		vc->vc_palette[k++] = default_red[j] ;
3473		vc->vc_palette[k++] = default_grn[j] ;
3474		vc->vc_palette[k++] = default_blu[j] ;
3475	}
3476	vc->vc_def_color       = default_color;
3477	vc->vc_ulcolor         = default_underline_color;
3478	vc->vc_itcolor         = default_italic_color;
3479	vc->vc_halfcolor       = 0x08;   /* grey */
3480	init_waitqueue_head(&vc->paste_wait);
3481	reset_terminal(vc, do_clear);
3482}
3483
3484/*
3485 * This routine initializes console interrupts, and does nothing
3486 * else. If you want the screen to clear, call tty_write with
3487 * the appropriate escape-sequence.
3488 */
3489
3490static int __init con_init(void)
3491{
3492	const char *display_desc = NULL;
3493	struct vc_data *vc;
3494	unsigned int currcons = 0, i;
3495
3496	console_lock();
3497
3498	if (!conswitchp)
3499		conswitchp = &dummy_con;
3500	display_desc = conswitchp->con_startup();
3501	if (!display_desc) {
3502		fg_console = 0;
3503		console_unlock();
3504		return 0;
3505	}
3506
3507	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3508		struct con_driver *con_driver = &registered_con_driver[i];
3509
3510		if (con_driver->con == NULL) {
3511			con_driver->con = conswitchp;
3512			con_driver->desc = display_desc;
3513			con_driver->flag = CON_DRIVER_FLAG_INIT;
3514			con_driver->first = 0;
3515			con_driver->last = MAX_NR_CONSOLES - 1;
3516			break;
3517		}
3518	}
3519
3520	for (i = 0; i < MAX_NR_CONSOLES; i++)
3521		con_driver_map[i] = conswitchp;
3522
3523	if (blankinterval) {
3524		blank_state = blank_normal_wait;
3525		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3526	}
3527
3528	for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) {
3529		vc_cons[currcons].d = vc = kzalloc(sizeof(struct vc_data), GFP_NOWAIT);
3530		INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
3531		tty_port_init(&vc->port);
3532		visual_init(vc, currcons, 1);
3533		/* Assuming vc->vc_{cols,rows,screenbuf_size} are sane here. */
3534		vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_NOWAIT);
3535		vc_init(vc, vc->vc_rows, vc->vc_cols,
3536			currcons || !vc->vc_sw->con_save_screen);
3537	}
3538	currcons = fg_console = 0;
3539	master_display_fg = vc = vc_cons[currcons].d;
3540	set_origin(vc);
3541	save_screen(vc);
3542	gotoxy(vc, vc->state.x, vc->state.y);
3543	csi_J(vc, 0);
3544	update_screen(vc);
3545	pr_info("Console: %s %s %dx%d\n",
3546		vc->vc_can_do_color ? "colour" : "mono",
3547		display_desc, vc->vc_cols, vc->vc_rows);
3548	printable = 1;
3549
3550	console_unlock();
3551
3552#ifdef CONFIG_VT_CONSOLE
3553	register_console(&vt_console_driver);
3554#endif
3555	return 0;
3556}
3557console_initcall(con_init);
3558
3559static const struct tty_operations con_ops = {
3560	.install = con_install,
3561	.open = con_open,
3562	.close = con_close,
3563	.write = con_write,
3564	.write_room = con_write_room,
3565	.put_char = con_put_char,
3566	.flush_chars = con_flush_chars,
3567	.chars_in_buffer = con_chars_in_buffer,
3568	.ioctl = vt_ioctl,
3569#ifdef CONFIG_COMPAT
3570	.compat_ioctl = vt_compat_ioctl,
3571#endif
3572	.stop = con_stop,
3573	.start = con_start,
3574	.throttle = con_throttle,
3575	.unthrottle = con_unthrottle,
3576	.resize = vt_resize,
3577	.shutdown = con_shutdown,
3578	.cleanup = con_cleanup,
3579};
3580
3581static struct cdev vc0_cdev;
3582
3583static ssize_t show_tty_active(struct device *dev,
3584				struct device_attribute *attr, char *buf)
3585{
3586	return sprintf(buf, "tty%d\n", fg_console + 1);
3587}
3588static DEVICE_ATTR(active, S_IRUGO, show_tty_active, NULL);
3589
3590static struct attribute *vt_dev_attrs[] = {
3591	&dev_attr_active.attr,
3592	NULL
3593};
3594
3595ATTRIBUTE_GROUPS(vt_dev);
3596
3597int __init vty_init(const struct file_operations *console_fops)
3598{
3599	cdev_init(&vc0_cdev, console_fops);
3600	if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
3601	    register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
3602		panic("Couldn't register /dev/tty0 driver\n");
3603	tty0dev = device_create_with_groups(tty_class, NULL,
3604					    MKDEV(TTY_MAJOR, 0), NULL,
3605					    vt_dev_groups, "tty0");
3606	if (IS_ERR(tty0dev))
3607		tty0dev = NULL;
3608
3609	vcs_init();
3610
3611	console_driver = alloc_tty_driver(MAX_NR_CONSOLES);
3612	if (!console_driver)
3613		panic("Couldn't allocate console driver\n");
3614
3615	console_driver->name = "tty";
3616	console_driver->name_base = 1;
3617	console_driver->major = TTY_MAJOR;
3618	console_driver->minor_start = 1;
3619	console_driver->type = TTY_DRIVER_TYPE_CONSOLE;
3620	console_driver->init_termios = tty_std_termios;
3621	if (default_utf8)
3622		console_driver->init_termios.c_iflag |= IUTF8;
3623	console_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS;
3624	tty_set_operations(console_driver, &con_ops);
3625	if (tty_register_driver(console_driver))
3626		panic("Couldn't register console driver\n");
3627	kbd_init();
3628	console_map_init();
3629#ifdef CONFIG_MDA_CONSOLE
3630	mda_console_init();
3631#endif
3632	return 0;
3633}
3634
3635#ifndef VT_SINGLE_DRIVER
3636
3637static struct class *vtconsole_class;
3638
3639static int do_bind_con_driver(const struct consw *csw, int first, int last,
3640			   int deflt)
3641{
3642	struct module *owner = csw->owner;
3643	const char *desc = NULL;
3644	struct con_driver *con_driver;
3645	int i, j = -1, k = -1, retval = -ENODEV;
3646
3647	if (!try_module_get(owner))
3648		return -ENODEV;
3649
3650	WARN_CONSOLE_UNLOCKED();
3651
3652	/* check if driver is registered */
3653	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3654		con_driver = &registered_con_driver[i];
3655
3656		if (con_driver->con == csw) {
3657			desc = con_driver->desc;
3658			retval = 0;
3659			break;
3660		}
3661	}
3662
3663	if (retval)
3664		goto err;
3665
3666	if (!(con_driver->flag & CON_DRIVER_FLAG_INIT)) {
3667		csw->con_startup();
3668		con_driver->flag |= CON_DRIVER_FLAG_INIT;
3669	}
3670
3671	if (deflt) {
3672		if (conswitchp)
3673			module_put(conswitchp->owner);
3674
3675		__module_get(owner);
3676		conswitchp = csw;
3677	}
3678
3679	first = max(first, con_driver->first);
3680	last = min(last, con_driver->last);
3681
3682	for (i = first; i <= last; i++) {
3683		int old_was_color;
3684		struct vc_data *vc = vc_cons[i].d;
3685
3686		if (con_driver_map[i])
3687			module_put(con_driver_map[i]->owner);
3688		__module_get(owner);
3689		con_driver_map[i] = csw;
3690
3691		if (!vc || !vc->vc_sw)
3692			continue;
3693
3694		j = i;
3695
3696		if (con_is_visible(vc)) {
3697			k = i;
3698			save_screen(vc);
3699		}
3700
3701		old_was_color = vc->vc_can_do_color;
3702		vc->vc_sw->con_deinit(vc);
3703		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
3704		visual_init(vc, i, 0);
3705		set_origin(vc);
3706		update_attr(vc);
3707
3708		/* If the console changed between mono <-> color, then
3709		 * the attributes in the screenbuf will be wrong.  The
3710		 * following resets all attributes to something sane.
3711		 */
3712		if (old_was_color != vc->vc_can_do_color)
3713			clear_buffer_attributes(vc);
3714	}
3715
3716	pr_info("Console: switching ");
3717	if (!deflt)
3718		pr_cont("consoles %d-%d ", first + 1, last + 1);
3719	if (j >= 0) {
3720		struct vc_data *vc = vc_cons[j].d;
3721
3722		pr_cont("to %s %s %dx%d\n",
3723			vc->vc_can_do_color ? "colour" : "mono",
3724			desc, vc->vc_cols, vc->vc_rows);
3725
3726		if (k >= 0) {
3727			vc = vc_cons[k].d;
3728			update_screen(vc);
3729		}
3730	} else {
3731		pr_cont("to %s\n", desc);
3732	}
3733
3734	retval = 0;
3735err:
3736	module_put(owner);
3737	return retval;
3738};
3739
3740
3741#ifdef CONFIG_VT_HW_CONSOLE_BINDING
3742int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
3743{
3744	struct module *owner = csw->owner;
3745	const struct consw *defcsw = NULL;
3746	struct con_driver *con_driver = NULL, *con_back = NULL;
3747	int i, retval = -ENODEV;
3748
3749	if (!try_module_get(owner))
3750		return -ENODEV;
3751
3752	WARN_CONSOLE_UNLOCKED();
3753
3754	/* check if driver is registered and if it is unbindable */
3755	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3756		con_driver = &registered_con_driver[i];
3757
3758		if (con_driver->con == csw &&
3759		    con_driver->flag & CON_DRIVER_FLAG_MODULE) {
3760			retval = 0;
3761			break;
3762		}
3763	}
3764
3765	if (retval)
3766		goto err;
3767
3768	retval = -ENODEV;
3769
3770	/* check if backup driver exists */
3771	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3772		con_back = &registered_con_driver[i];
3773
3774		if (con_back->con && con_back->con != csw) {
3775			defcsw = con_back->con;
3776			retval = 0;
3777			break;
3778		}
3779	}
3780
3781	if (retval)
3782		goto err;
3783
3784	if (!con_is_bound(csw))
3785		goto err;
3786
3787	first = max(first, con_driver->first);
3788	last = min(last, con_driver->last);
3789
3790	for (i = first; i <= last; i++) {
3791		if (con_driver_map[i] == csw) {
3792			module_put(csw->owner);
3793			con_driver_map[i] = NULL;
3794		}
3795	}
3796
3797	if (!con_is_bound(defcsw)) {
3798		const struct consw *defconsw = conswitchp;
3799
3800		defcsw->con_startup();
3801		con_back->flag |= CON_DRIVER_FLAG_INIT;
3802		/*
3803		 * vgacon may change the default driver to point
3804		 * to dummycon, we restore it here...
3805		 */
3806		conswitchp = defconsw;
3807	}
3808
3809	if (!con_is_bound(csw))
3810		con_driver->flag &= ~CON_DRIVER_FLAG_INIT;
3811
3812	/* ignore return value, binding should not fail */
3813	do_bind_con_driver(defcsw, first, last, deflt);
3814err:
3815	module_put(owner);
3816	return retval;
3817
3818}
3819EXPORT_SYMBOL_GPL(do_unbind_con_driver);
3820
3821static int vt_bind(struct con_driver *con)
3822{
3823	const struct consw *defcsw = NULL, *csw = NULL;
3824	int i, more = 1, first = -1, last = -1, deflt = 0;
3825
3826 	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3827		goto err;
3828
3829	csw = con->con;
3830
3831	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3832		struct con_driver *con = &registered_con_driver[i];
3833
3834		if (con->con && !(con->flag & CON_DRIVER_FLAG_MODULE)) {
3835			defcsw = con->con;
3836			break;
3837		}
3838	}
3839
3840	if (!defcsw)
3841		goto err;
3842
3843	while (more) {
3844		more = 0;
3845
3846		for (i = con->first; i <= con->last; i++) {
3847			if (con_driver_map[i] == defcsw) {
3848				if (first == -1)
3849					first = i;
3850				last = i;
3851				more = 1;
3852			} else if (first != -1)
3853				break;
3854		}
3855
3856		if (first == 0 && last == MAX_NR_CONSOLES -1)
3857			deflt = 1;
3858
3859		if (first != -1)
3860			do_bind_con_driver(csw, first, last, deflt);
3861
3862		first = -1;
3863		last = -1;
3864		deflt = 0;
3865	}
3866
3867err:
3868	return 0;
3869}
3870
3871static int vt_unbind(struct con_driver *con)
3872{
3873	const struct consw *csw = NULL;
3874	int i, more = 1, first = -1, last = -1, deflt = 0;
3875	int ret;
3876
3877 	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3878		goto err;
3879
3880	csw = con->con;
3881
3882	while (more) {
3883		more = 0;
3884
3885		for (i = con->first; i <= con->last; i++) {
3886			if (con_driver_map[i] == csw) {
3887				if (first == -1)
3888					first = i;
3889				last = i;
3890				more = 1;
3891			} else if (first != -1)
3892				break;
3893		}
3894
3895		if (first == 0 && last == MAX_NR_CONSOLES -1)
3896			deflt = 1;
3897
3898		if (first != -1) {
3899			ret = do_unbind_con_driver(csw, first, last, deflt);
3900			if (ret != 0)
3901				return ret;
3902		}
3903
3904		first = -1;
3905		last = -1;
3906		deflt = 0;
3907	}
3908
3909err:
3910	return 0;
3911}
3912#else
3913static inline int vt_bind(struct con_driver *con)
3914{
3915	return 0;
3916}
3917static inline int vt_unbind(struct con_driver *con)
3918{
3919	return 0;
3920}
3921#endif /* CONFIG_VT_HW_CONSOLE_BINDING */
3922
3923static ssize_t store_bind(struct device *dev, struct device_attribute *attr,
3924			  const char *buf, size_t count)
3925{
3926	struct con_driver *con = dev_get_drvdata(dev);
3927	int bind = simple_strtoul(buf, NULL, 0);
3928
3929	console_lock();
3930
3931	if (bind)
3932		vt_bind(con);
3933	else
3934		vt_unbind(con);
3935
3936	console_unlock();
3937
3938	return count;
3939}
3940
3941static ssize_t show_bind(struct device *dev, struct device_attribute *attr,
3942			 char *buf)
3943{
3944	struct con_driver *con = dev_get_drvdata(dev);
3945	int bind;
3946
3947	console_lock();
3948	bind = con_is_bound(con->con);
3949	console_unlock();
3950
3951	return snprintf(buf, PAGE_SIZE, "%i\n", bind);
3952}
3953
3954static ssize_t show_name(struct device *dev, struct device_attribute *attr,
3955			 char *buf)
3956{
3957	struct con_driver *con = dev_get_drvdata(dev);
3958
3959	return snprintf(buf, PAGE_SIZE, "%s %s\n",
3960			(con->flag & CON_DRIVER_FLAG_MODULE) ? "(M)" : "(S)",
3961			 con->desc);
3962
3963}
3964
3965static DEVICE_ATTR(bind, S_IRUGO|S_IWUSR, show_bind, store_bind);
3966static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
3967
3968static struct attribute *con_dev_attrs[] = {
3969	&dev_attr_bind.attr,
3970	&dev_attr_name.attr,
3971	NULL
3972};
3973
3974ATTRIBUTE_GROUPS(con_dev);
3975
3976static int vtconsole_init_device(struct con_driver *con)
3977{
3978	con->flag |= CON_DRIVER_FLAG_ATTR;
3979	return 0;
3980}
3981
3982static void vtconsole_deinit_device(struct con_driver *con)
3983{
3984	con->flag &= ~CON_DRIVER_FLAG_ATTR;
3985}
3986
3987/**
3988 * con_is_bound - checks if driver is bound to the console
3989 * @csw: console driver
3990 *
3991 * RETURNS: zero if unbound, nonzero if bound
3992 *
3993 * Drivers can call this and if zero, they should release
3994 * all resources allocated on con_startup()
3995 */
3996int con_is_bound(const struct consw *csw)
3997{
3998	int i, bound = 0;
3999
4000	WARN_CONSOLE_UNLOCKED();
4001
4002	for (i = 0; i < MAX_NR_CONSOLES; i++) {
4003		if (con_driver_map[i] == csw) {
4004			bound = 1;
4005			break;
4006		}
4007	}
4008
4009	return bound;
4010}
4011EXPORT_SYMBOL(con_is_bound);
4012
4013/**
4014 * con_is_visible - checks whether the current console is visible
4015 * @vc: virtual console
4016 *
4017 * RETURNS: zero if not visible, nonzero if visible
4018 */
4019bool con_is_visible(const struct vc_data *vc)
4020{
4021	WARN_CONSOLE_UNLOCKED();
4022
4023	return *vc->vc_display_fg == vc;
4024}
4025EXPORT_SYMBOL(con_is_visible);
4026
4027/**
4028 * con_debug_enter - prepare the console for the kernel debugger
4029 * @vc: virtual console
4030 *
4031 * Called when the console is taken over by the kernel debugger, this
4032 * function needs to save the current console state, then put the console
4033 * into a state suitable for the kernel debugger.
4034 *
4035 * RETURNS:
4036 * Zero on success, nonzero if a failure occurred when trying to prepare
4037 * the console for the debugger.
4038 */
4039int con_debug_enter(struct vc_data *vc)
4040{
4041	int ret = 0;
4042
4043	saved_fg_console = fg_console;
4044	saved_last_console = last_console;
4045	saved_want_console = want_console;
4046	saved_vc_mode = vc->vc_mode;
4047	saved_console_blanked = console_blanked;
4048	vc->vc_mode = KD_TEXT;
4049	console_blanked = 0;
4050	if (vc->vc_sw->con_debug_enter)
4051		ret = vc->vc_sw->con_debug_enter(vc);
4052#ifdef CONFIG_KGDB_KDB
4053	/* Set the initial LINES variable if it is not already set */
4054	if (vc->vc_rows < 999) {
4055		int linecount;
4056		char lns[4];
4057		const char *setargs[3] = {
4058			"set",
4059			"LINES",
4060			lns,
4061		};
4062		if (kdbgetintenv(setargs[0], &linecount)) {
4063			snprintf(lns, 4, "%i", vc->vc_rows);
4064			kdb_set(2, setargs);
4065		}
4066	}
4067	if (vc->vc_cols < 999) {
4068		int colcount;
4069		char cols[4];
4070		const char *setargs[3] = {
4071			"set",
4072			"COLUMNS",
4073			cols,
4074		};
4075		if (kdbgetintenv(setargs[0], &colcount)) {
4076			snprintf(cols, 4, "%i", vc->vc_cols);
4077			kdb_set(2, setargs);
4078		}
4079	}
4080#endif /* CONFIG_KGDB_KDB */
4081	return ret;
4082}
4083EXPORT_SYMBOL_GPL(con_debug_enter);
4084
4085/**
4086 * con_debug_leave - restore console state
4087 *
4088 * Restore the console state to what it was before the kernel debugger
4089 * was invoked.
4090 *
4091 * RETURNS:
4092 * Zero on success, nonzero if a failure occurred when trying to restore
4093 * the console.
4094 */
4095int con_debug_leave(void)
4096{
4097	struct vc_data *vc;
4098	int ret = 0;
4099
4100	fg_console = saved_fg_console;
4101	last_console = saved_last_console;
4102	want_console = saved_want_console;
4103	console_blanked = saved_console_blanked;
4104	vc_cons[fg_console].d->vc_mode = saved_vc_mode;
4105
4106	vc = vc_cons[fg_console].d;
4107	if (vc->vc_sw->con_debug_leave)
4108		ret = vc->vc_sw->con_debug_leave(vc);
4109	return ret;
4110}
4111EXPORT_SYMBOL_GPL(con_debug_leave);
4112
4113static int do_register_con_driver(const struct consw *csw, int first, int last)
4114{
4115	struct module *owner = csw->owner;
4116	struct con_driver *con_driver;
4117	const char *desc;
4118	int i, retval;
4119
4120	WARN_CONSOLE_UNLOCKED();
4121
4122	if (!try_module_get(owner))
4123		return -ENODEV;
4124
4125	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4126		con_driver = &registered_con_driver[i];
4127
4128		/* already registered */
4129		if (con_driver->con == csw) {
4130			retval = -EBUSY;
4131			goto err;
4132		}
4133	}
4134
4135	desc = csw->con_startup();
4136	if (!desc) {
4137		retval = -ENODEV;
4138		goto err;
4139	}
4140
4141	retval = -EINVAL;
4142
4143	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4144		con_driver = &registered_con_driver[i];
4145
4146		if (con_driver->con == NULL &&
4147		    !(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE)) {
4148			con_driver->con = csw;
4149			con_driver->desc = desc;
4150			con_driver->node = i;
4151			con_driver->flag = CON_DRIVER_FLAG_MODULE |
4152			                   CON_DRIVER_FLAG_INIT;
4153			con_driver->first = first;
4154			con_driver->last = last;
4155			retval = 0;
4156			break;
4157		}
4158	}
4159
4160	if (retval)
4161		goto err;
4162
4163	con_driver->dev =
4164		device_create_with_groups(vtconsole_class, NULL,
4165					  MKDEV(0, con_driver->node),
4166					  con_driver, con_dev_groups,
4167					  "vtcon%i", con_driver->node);
4168	if (IS_ERR(con_driver->dev)) {
4169		pr_warn("Unable to create device for %s; errno = %ld\n",
4170			con_driver->desc, PTR_ERR(con_driver->dev));
4171		con_driver->dev = NULL;
4172	} else {
4173		vtconsole_init_device(con_driver);
4174	}
4175
4176err:
4177	module_put(owner);
4178	return retval;
4179}
4180
4181
4182/**
4183 * do_unregister_con_driver - unregister console driver from console layer
4184 * @csw: console driver
4185 *
4186 * DESCRIPTION: All drivers that registers to the console layer must
4187 * call this function upon exit, or if the console driver is in a state
4188 * where it won't be able to handle console services, such as the
4189 * framebuffer console without loaded framebuffer drivers.
4190 *
4191 * The driver must unbind first prior to unregistration.
4192 */
4193int do_unregister_con_driver(const struct consw *csw)
4194{
4195	int i;
4196
4197	/* cannot unregister a bound driver */
4198	if (con_is_bound(csw))
4199		return -EBUSY;
4200
4201	if (csw == conswitchp)
4202		return -EINVAL;
4203
4204	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4205		struct con_driver *con_driver = &registered_con_driver[i];
4206
4207		if (con_driver->con == csw) {
4208			/*
4209			 * Defer the removal of the sysfs entries since that
4210			 * will acquire the kernfs s_active lock and we can't
4211			 * acquire this lock while holding the console lock:
4212			 * the unbind sysfs entry imposes already the opposite
4213			 * order. Reset con already here to prevent any later
4214			 * lookup to succeed and mark this slot as zombie, so
4215			 * it won't get reused until we complete the removal
4216			 * in the deferred work.
4217			 */
4218			con_driver->con = NULL;
4219			con_driver->flag = CON_DRIVER_FLAG_ZOMBIE;
4220			schedule_work(&con_driver_unregister_work);
4221
4222			return 0;
4223		}
4224	}
4225
4226	return -ENODEV;
4227}
4228EXPORT_SYMBOL_GPL(do_unregister_con_driver);
4229
4230static void con_driver_unregister_callback(struct work_struct *ignored)
4231{
4232	int i;
4233
4234	console_lock();
4235
4236	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4237		struct con_driver *con_driver = &registered_con_driver[i];
4238
4239		if (!(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE))
4240			continue;
4241
4242		console_unlock();
4243
4244		vtconsole_deinit_device(con_driver);
4245		device_destroy(vtconsole_class, MKDEV(0, con_driver->node));
4246
4247		console_lock();
4248
4249		if (WARN_ON_ONCE(con_driver->con))
4250			con_driver->con = NULL;
4251		con_driver->desc = NULL;
4252		con_driver->dev = NULL;
4253		con_driver->node = 0;
4254		WARN_ON_ONCE(con_driver->flag != CON_DRIVER_FLAG_ZOMBIE);
4255		con_driver->flag = 0;
4256		con_driver->first = 0;
4257		con_driver->last = 0;
4258	}
4259
4260	console_unlock();
4261}
4262
4263/*
4264 *	If we support more console drivers, this function is used
4265 *	when a driver wants to take over some existing consoles
4266 *	and become default driver for newly opened ones.
4267 *
4268 *	do_take_over_console is basically a register followed by bind
4269 */
4270int do_take_over_console(const struct consw *csw, int first, int last, int deflt)
4271{
4272	int err;
4273
4274	err = do_register_con_driver(csw, first, last);
4275	/*
4276	 * If we get an busy error we still want to bind the console driver
4277	 * and return success, as we may have unbound the console driver
4278	 * but not unregistered it.
4279	 */
4280	if (err == -EBUSY)
4281		err = 0;
4282	if (!err)
4283		do_bind_con_driver(csw, first, last, deflt);
4284
4285	return err;
4286}
4287EXPORT_SYMBOL_GPL(do_take_over_console);
4288
4289
4290/*
4291 * give_up_console is a wrapper to unregister_con_driver. It will only
4292 * work if driver is fully unbound.
4293 */
4294void give_up_console(const struct consw *csw)
4295{
4296	console_lock();
4297	do_unregister_con_driver(csw);
4298	console_unlock();
4299}
4300
4301static int __init vtconsole_class_init(void)
4302{
4303	int i;
4304
4305	vtconsole_class = class_create(THIS_MODULE, "vtconsole");
4306	if (IS_ERR(vtconsole_class)) {
4307		pr_warn("Unable to create vt console class; errno = %ld\n",
4308			PTR_ERR(vtconsole_class));
4309		vtconsole_class = NULL;
4310	}
4311
4312	/* Add system drivers to sysfs */
4313	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
4314		struct con_driver *con = &registered_con_driver[i];
4315
4316		if (con->con && !con->dev) {
4317			con->dev =
4318				device_create_with_groups(vtconsole_class, NULL,
4319							  MKDEV(0, con->node),
4320							  con, con_dev_groups,
4321							  "vtcon%i", con->node);
4322
4323			if (IS_ERR(con->dev)) {
4324				pr_warn("Unable to create device for %s; errno = %ld\n",
4325					con->desc, PTR_ERR(con->dev));
4326				con->dev = NULL;
4327			} else {
4328				vtconsole_init_device(con);
4329			}
4330		}
4331	}
4332
4333	return 0;
4334}
4335postcore_initcall(vtconsole_class_init);
4336
4337#endif
4338
4339/*
4340 *	Screen blanking
4341 */
4342
4343static int set_vesa_blanking(char __user *p)
4344{
4345	unsigned int mode;
4346
4347	if (get_user(mode, p + 1))
4348		return -EFAULT;
4349
4350	vesa_blank_mode = (mode < 4) ? mode : 0;
4351	return 0;
4352}
4353
4354void do_blank_screen(int entering_gfx)
4355{
4356	struct vc_data *vc = vc_cons[fg_console].d;
4357	int i;
4358
4359	might_sleep();
4360
4361	WARN_CONSOLE_UNLOCKED();
4362
4363	if (console_blanked) {
4364		if (blank_state == blank_vesa_wait) {
4365			blank_state = blank_off;
4366			vc->vc_sw->con_blank(vc, vesa_blank_mode + 1, 0);
4367		}
4368		return;
4369	}
4370
4371	/* entering graphics mode? */
4372	if (entering_gfx) {
4373		hide_cursor(vc);
4374		save_screen(vc);
4375		vc->vc_sw->con_blank(vc, -1, 1);
4376		console_blanked = fg_console + 1;
4377		blank_state = blank_off;
4378		set_origin(vc);
4379		return;
4380	}
4381
4382	blank_state = blank_off;
4383
4384	/* don't blank graphics */
4385	if (vc->vc_mode != KD_TEXT) {
4386		console_blanked = fg_console + 1;
4387		return;
4388	}
4389
4390	hide_cursor(vc);
4391	del_timer_sync(&console_timer);
4392	blank_timer_expired = 0;
4393
4394	save_screen(vc);
4395	/* In case we need to reset origin, blanking hook returns 1 */
4396	i = vc->vc_sw->con_blank(vc, vesa_off_interval ? 1 : (vesa_blank_mode + 1), 0);
4397	console_blanked = fg_console + 1;
4398	if (i)
4399		set_origin(vc);
4400
4401	if (console_blank_hook && console_blank_hook(1))
4402		return;
4403
4404	if (vesa_off_interval && vesa_blank_mode) {
4405		blank_state = blank_vesa_wait;
4406		mod_timer(&console_timer, jiffies + vesa_off_interval);
4407	}
4408	vt_event_post(VT_EVENT_BLANK, vc->vc_num, vc->vc_num);
4409}
4410EXPORT_SYMBOL(do_blank_screen);
4411
4412/*
4413 * Called by timer as well as from vt_console_driver
4414 */
4415void do_unblank_screen(int leaving_gfx)
4416{
4417	struct vc_data *vc;
4418
4419	/* This should now always be called from a "sane" (read: can schedule)
4420	 * context for the sake of the low level drivers, except in the special
4421	 * case of oops_in_progress
4422	 */
4423	if (!oops_in_progress)
4424		might_sleep();
4425
4426	WARN_CONSOLE_UNLOCKED();
4427
4428	ignore_poke = 0;
4429	if (!console_blanked)
4430		return;
4431	if (!vc_cons_allocated(fg_console)) {
4432		/* impossible */
4433		pr_warn("unblank_screen: tty %d not allocated ??\n",
4434			fg_console + 1);
4435		return;
4436	}
4437	vc = vc_cons[fg_console].d;
4438	if (vc->vc_mode != KD_TEXT)
4439		return; /* but leave console_blanked != 0 */
4440
4441	if (blankinterval) {
4442		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4443		blank_state = blank_normal_wait;
4444	}
4445
4446	console_blanked = 0;
4447	if (vc->vc_sw->con_blank(vc, 0, leaving_gfx))
4448		/* Low-level driver cannot restore -> do it ourselves */
4449		update_screen(vc);
4450	if (console_blank_hook)
4451		console_blank_hook(0);
4452	set_palette(vc);
4453	set_cursor(vc);
4454	vt_event_post(VT_EVENT_UNBLANK, vc->vc_num, vc->vc_num);
4455}
4456EXPORT_SYMBOL(do_unblank_screen);
4457
4458/*
4459 * This is called by the outside world to cause a forced unblank, mostly for
4460 * oopses. Currently, I just call do_unblank_screen(0), but we could eventually
4461 * call it with 1 as an argument and so force a mode restore... that may kill
4462 * X or at least garbage the screen but would also make the Oops visible...
4463 */
4464void unblank_screen(void)
4465{
4466	do_unblank_screen(0);
4467}
4468
4469/*
4470 * We defer the timer blanking to work queue so it can take the console mutex
4471 * (console operations can still happen at irq time, but only from printk which
4472 * has the console mutex. Not perfect yet, but better than no locking
4473 */
4474static void blank_screen_t(struct timer_list *unused)
4475{
4476	blank_timer_expired = 1;
4477	schedule_work(&console_work);
4478}
4479
4480void poke_blanked_console(void)
4481{
4482	WARN_CONSOLE_UNLOCKED();
4483
4484	/* Add this so we quickly catch whoever might call us in a non
4485	 * safe context. Nowadays, unblank_screen() isn't to be called in
4486	 * atomic contexts and is allowed to schedule (with the special case
4487	 * of oops_in_progress, but that isn't of any concern for this
4488	 * function. --BenH.
4489	 */
4490	might_sleep();
4491
4492	/* This isn't perfectly race free, but a race here would be mostly harmless,
4493	 * at worse, we'll do a spurrious blank and it's unlikely
4494	 */
4495	del_timer(&console_timer);
4496	blank_timer_expired = 0;
4497
4498	if (ignore_poke || !vc_cons[fg_console].d || vc_cons[fg_console].d->vc_mode == KD_GRAPHICS)
4499		return;
4500	if (console_blanked)
4501		unblank_screen();
4502	else if (blankinterval) {
4503		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
4504		blank_state = blank_normal_wait;
4505	}
4506}
4507
4508/*
4509 *	Palettes
4510 */
4511
4512static void set_palette(struct vc_data *vc)
4513{
4514	WARN_CONSOLE_UNLOCKED();
4515
4516	if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_set_palette)
4517		vc->vc_sw->con_set_palette(vc, color_table);
4518}
4519
4520/*
4521 * Load palette into the DAC registers. arg points to a colour
4522 * map, 3 bytes per colour, 16 colours, range from 0 to 255.
4523 */
4524
4525int con_set_cmap(unsigned char __user *arg)
4526{
4527	int i, j, k;
4528	unsigned char colormap[3*16];
4529
4530	if (copy_from_user(colormap, arg, sizeof(colormap)))
4531		return -EFAULT;
4532
4533	console_lock();
4534	for (i = k = 0; i < 16; i++) {
4535		default_red[i] = colormap[k++];
4536		default_grn[i] = colormap[k++];
4537		default_blu[i] = colormap[k++];
4538	}
4539	for (i = 0; i < MAX_NR_CONSOLES; i++) {
4540		if (!vc_cons_allocated(i))
4541			continue;
4542		for (j = k = 0; j < 16; j++) {
4543			vc_cons[i].d->vc_palette[k++] = default_red[j];
4544			vc_cons[i].d->vc_palette[k++] = default_grn[j];
4545			vc_cons[i].d->vc_palette[k++] = default_blu[j];
4546		}
4547		set_palette(vc_cons[i].d);
4548	}
4549	console_unlock();
4550
4551	return 0;
4552}
4553
4554int con_get_cmap(unsigned char __user *arg)
4555{
4556	int i, k;
4557	unsigned char colormap[3*16];
4558
4559	console_lock();
4560	for (i = k = 0; i < 16; i++) {
4561		colormap[k++] = default_red[i];
4562		colormap[k++] = default_grn[i];
4563		colormap[k++] = default_blu[i];
4564	}
4565	console_unlock();
4566
4567	if (copy_to_user(arg, colormap, sizeof(colormap)))
4568		return -EFAULT;
4569
4570	return 0;
4571}
4572
4573void reset_palette(struct vc_data *vc)
4574{
4575	int j, k;
4576	for (j=k=0; j<16; j++) {
4577		vc->vc_palette[k++] = default_red[j];
4578		vc->vc_palette[k++] = default_grn[j];
4579		vc->vc_palette[k++] = default_blu[j];
4580	}
4581	set_palette(vc);
4582}
4583
4584/*
4585 *  Font switching
4586 *
4587 *  Currently we only support fonts up to 32 pixels wide, at a maximum height
4588 *  of 32 pixels. Userspace fontdata is stored with 32 bytes (shorts/ints,
4589 *  depending on width) reserved for each character which is kinda wasty, but
4590 *  this is done in order to maintain compatibility with the EGA/VGA fonts. It
4591 *  is up to the actual low-level console-driver convert data into its favorite
4592 *  format (maybe we should add a `fontoffset' field to the `display'
4593 *  structure so we won't have to convert the fontdata all the time.
4594 *  /Jes
4595 */
4596
4597#define max_font_size 65536
4598
4599static int con_font_get(struct vc_data *vc, struct console_font_op *op)
4600{
4601	struct console_font font;
4602	int rc = -EINVAL;
4603	int c;
4604
4605	if (op->data) {
4606		font.data = kmalloc(max_font_size, GFP_KERNEL);
4607		if (!font.data)
4608			return -ENOMEM;
4609	} else
4610		font.data = NULL;
4611
4612	console_lock();
4613	if (vc->vc_mode != KD_TEXT)
4614		rc = -EINVAL;
4615	else if (vc->vc_sw->con_font_get)
4616		rc = vc->vc_sw->con_font_get(vc, &font);
4617	else
4618		rc = -ENOSYS;
4619	console_unlock();
4620
4621	if (rc)
4622		goto out;
4623
4624	c = (font.width+7)/8 * 32 * font.charcount;
4625
4626	if (op->data && font.charcount > op->charcount)
4627		rc = -ENOSPC;
4628	if (font.width > op->width || font.height > op->height)
4629		rc = -ENOSPC;
4630	if (rc)
4631		goto out;
4632
4633	op->height = font.height;
4634	op->width = font.width;
4635	op->charcount = font.charcount;
4636
4637	if (op->data && copy_to_user(op->data, font.data, c))
4638		rc = -EFAULT;
4639
4640out:
4641	kfree(font.data);
4642	return rc;
4643}
4644
4645static int con_font_set(struct vc_data *vc, struct console_font_op *op)
4646{
4647	struct console_font font;
4648	int rc = -EINVAL;
4649	int size;
4650
4651	if (vc->vc_mode != KD_TEXT)
4652		return -EINVAL;
4653	if (!op->data)
4654		return -EINVAL;
4655	if (op->charcount > 512)
4656		return -EINVAL;
4657	if (op->width <= 0 || op->width > 32 || !op->height || op->height > 32)
4658		return -EINVAL;
4659	size = (op->width+7)/8 * 32 * op->charcount;
4660	if (size > max_font_size)
4661		return -ENOSPC;
4662
4663	font.data = memdup_user(op->data, size);
4664	if (IS_ERR(font.data))
4665		return PTR_ERR(font.data);
4666
4667	font.charcount = op->charcount;
4668	font.width = op->width;
4669	font.height = op->height;
4670
4671	console_lock();
4672	if (vc->vc_mode != KD_TEXT)
4673		rc = -EINVAL;
4674	else if (vc->vc_sw->con_font_set) {
4675		if (vc_is_sel(vc))
4676			clear_selection();
4677		rc = vc->vc_sw->con_font_set(vc, &font, op->flags);
4678	} else
4679		rc = -ENOSYS;
4680	console_unlock();
4681	kfree(font.data);
4682	return rc;
4683}
4684
4685static int con_font_default(struct vc_data *vc, struct console_font_op *op)
4686{
4687	struct console_font font = {.width = op->width, .height = op->height};
4688	char name[MAX_FONT_NAME];
4689	char *s = name;
4690	int rc;
4691
4692
4693	if (!op->data)
4694		s = NULL;
4695	else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0)
4696		return -EFAULT;
4697	else
4698		name[MAX_FONT_NAME - 1] = 0;
4699
4700	console_lock();
4701	if (vc->vc_mode != KD_TEXT) {
4702		console_unlock();
4703		return -EINVAL;
4704	}
4705	if (vc->vc_sw->con_font_default) {
4706		if (vc_is_sel(vc))
4707			clear_selection();
4708		rc = vc->vc_sw->con_font_default(vc, &font, s);
4709	} else
4710		rc = -ENOSYS;
4711	console_unlock();
4712	if (!rc) {
4713		op->width = font.width;
4714		op->height = font.height;
4715	}
4716	return rc;
4717}
4718
4719int con_font_op(struct vc_data *vc, struct console_font_op *op)
4720{
4721	switch (op->op) {
4722	case KD_FONT_OP_SET:
4723		return con_font_set(vc, op);
4724	case KD_FONT_OP_GET:
4725		return con_font_get(vc, op);
4726	case KD_FONT_OP_SET_DEFAULT:
4727		return con_font_default(vc, op);
4728	case KD_FONT_OP_COPY:
4729		/* was buggy and never really used */
4730		return -EINVAL;
4731	}
4732	return -ENOSYS;
4733}
4734
4735/*
4736 *	Interface exported to selection and vcs.
4737 */
4738
4739/* used by selection */
4740u16 screen_glyph(const struct vc_data *vc, int offset)
4741{
4742	u16 w = scr_readw(screenpos(vc, offset, true));
4743	u16 c = w & 0xff;
4744
4745	if (w & vc->vc_hi_font_mask)
4746		c |= 0x100;
4747	return c;
4748}
4749EXPORT_SYMBOL_GPL(screen_glyph);
4750
4751u32 screen_glyph_unicode(const struct vc_data *vc, int n)
4752{
4753	struct uni_screen *uniscr = get_vc_uniscr(vc);
4754
4755	if (uniscr)
4756		return uniscr->lines[n / vc->vc_cols][n % vc->vc_cols];
4757	return inverse_translate(vc, screen_glyph(vc, n * 2), 1);
4758}
4759EXPORT_SYMBOL_GPL(screen_glyph_unicode);
4760
4761/* used by vcs - note the word offset */
4762unsigned short *screen_pos(const struct vc_data *vc, int w_offset, bool viewed)
4763{
4764	return screenpos(vc, 2 * w_offset, viewed);
4765}
4766EXPORT_SYMBOL_GPL(screen_pos);
4767
4768void getconsxy(const struct vc_data *vc, unsigned char xy[static 2])
4769{
4770	/* clamp values if they don't fit */
4771	xy[0] = min(vc->state.x, 0xFFu);
4772	xy[1] = min(vc->state.y, 0xFFu);
4773}
4774
4775void putconsxy(struct vc_data *vc, unsigned char xy[static const 2])
4776{
4777	hide_cursor(vc);
4778	gotoxy(vc, xy[0], xy[1]);
4779	set_cursor(vc);
4780}
4781
4782u16 vcs_scr_readw(const struct vc_data *vc, const u16 *org)
4783{
4784	if ((unsigned long)org == vc->vc_pos && softcursor_original != -1)
4785		return softcursor_original;
4786	return scr_readw(org);
4787}
4788
4789void vcs_scr_writew(struct vc_data *vc, u16 val, u16 *org)
4790{
4791	scr_writew(val, org);
4792	if ((unsigned long)org == vc->vc_pos) {
4793		softcursor_original = -1;
4794		add_softcursor(vc);
4795	}
4796}
4797
4798void vcs_scr_updated(struct vc_data *vc)
4799{
4800	notify_update(vc);
4801}
4802
4803void vc_scrolldelta_helper(struct vc_data *c, int lines,
4804		unsigned int rolled_over, void *base, unsigned int size)
4805{
4806	unsigned long ubase = (unsigned long)base;
4807	ptrdiff_t scr_end = (void *)c->vc_scr_end - base;
4808	ptrdiff_t vorigin = (void *)c->vc_visible_origin - base;
4809	ptrdiff_t origin = (void *)c->vc_origin - base;
4810	int margin = c->vc_size_row * 4;
4811	int from, wrap, from_off, avail;
4812
4813	/* Turn scrollback off */
4814	if (!lines) {
4815		c->vc_visible_origin = c->vc_origin;
4816		return;
4817	}
4818
4819	/* Do we have already enough to allow jumping from 0 to the end? */
4820	if (rolled_over > scr_end + margin) {
4821		from = scr_end;
4822		wrap = rolled_over + c->vc_size_row;
4823	} else {
4824		from = 0;
4825		wrap = size;
4826	}
4827
4828	from_off = (vorigin - from + wrap) % wrap + lines * c->vc_size_row;
4829	avail = (origin - from + wrap) % wrap;
4830
4831	/* Only a little piece would be left? Show all incl. the piece! */
4832	if (avail < 2 * margin)
4833		margin = 0;
4834	if (from_off < margin)
4835		from_off = 0;
4836	if (from_off > avail - margin)
4837		from_off = avail;
4838
4839	c->vc_visible_origin = ubase + (from + from_off) % wrap;
4840}
4841EXPORT_SYMBOL_GPL(vc_scrolldelta_helper);
4842
4843/*
4844 *	Visible symbols for modules
4845 */
4846
4847EXPORT_SYMBOL(color_table);
4848EXPORT_SYMBOL(default_red);
4849EXPORT_SYMBOL(default_grn);
4850EXPORT_SYMBOL(default_blu);
4851EXPORT_SYMBOL(update_region);
4852EXPORT_SYMBOL(redraw_screen);
4853EXPORT_SYMBOL(vc_resize);
4854EXPORT_SYMBOL(fg_console);
4855EXPORT_SYMBOL(console_blank_hook);
4856EXPORT_SYMBOL(console_blanked);
4857EXPORT_SYMBOL(vc_cons);
4858EXPORT_SYMBOL(global_cursor_default);
4859#ifndef VT_SINGLE_DRIVER
4860EXPORT_SYMBOL(give_up_console);
4861#endif
4862