xref: /openbmc/linux/drivers/tty/vt/vt.c (revision 82003e04)
1 /*
2  *  Copyright (C) 1991, 1992  Linus Torvalds
3  */
4 
5 /*
6  * Hopefully this will be a rather complete VT102 implementation.
7  *
8  * Beeping thanks to John T Kohl.
9  *
10  * Virtual Consoles, Screen Blanking, Screen Dumping, Color, Graphics
11  *   Chars, and VT100 enhancements by Peter MacDonald.
12  *
13  * Copy and paste function by Andrew Haylett,
14  *   some enhancements by Alessandro Rubini.
15  *
16  * Code to check for different video-cards mostly by Galen Hunt,
17  * <g-hunt@ee.utah.edu>
18  *
19  * Rudimentary ISO 10646/Unicode/UTF-8 character set support by
20  * Markus Kuhn, <mskuhn@immd4.informatik.uni-erlangen.de>.
21  *
22  * Dynamic allocation of consoles, aeb@cwi.nl, May 1994
23  * Resizing of consoles, aeb, 940926
24  *
25  * Code for xterm like mouse click reporting by Peter Orbaek 20-Jul-94
26  * <poe@daimi.aau.dk>
27  *
28  * User-defined bell sound, new setterm control sequences and printk
29  * redirection by Martin Mares <mj@k332.feld.cvut.cz> 19-Nov-95
30  *
31  * APM screenblank bug fixed Takashi Manabe <manabe@roy.dsl.tutics.tut.jp>
32  *
33  * Merge with the abstract console driver by Geert Uytterhoeven
34  * <geert@linux-m68k.org>, Jan 1997.
35  *
36  *   Original m68k console driver modifications by
37  *
38  *     - Arno Griffioen <arno@usn.nl>
39  *     - David Carter <carter@cs.bris.ac.uk>
40  *
41  *   The abstract console driver provides a generic interface for a text
42  *   console. It supports VGA text mode, frame buffer based graphical consoles
43  *   and special graphics processors that are only accessible through some
44  *   registers (e.g. a TMS340x0 GSP).
45  *
46  *   The interface to the hardware is specified using a special structure
47  *   (struct consw) which contains function pointers to console operations
48  *   (see <linux/console.h> for more information).
49  *
50  * Support for changeable cursor shape
51  * by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz>, August 1997
52  *
53  * Ported to i386 and con_scrolldelta fixed
54  * by Emmanuel Marty <core@ggi-project.org>, April 1998
55  *
56  * Resurrected character buffers in videoram plus lots of other trickery
57  * by Martin Mares <mj@atrey.karlin.mff.cuni.cz>, July 1998
58  *
59  * Removed old-style timers, introduced console_timer, made timer
60  * deletion SMP-safe.  17Jun00, Andrew Morton
61  *
62  * Removed console_lock, enabled interrupts across all console operations
63  * 13 March 2001, Andrew Morton
64  *
65  * Fixed UTF-8 mode so alternate charset modes always work according
66  * to control sequences interpreted in do_con_trol function
67  * preserving backward VT100 semigraphics compatibility,
68  * malformed UTF sequences represented as sequences of replacement glyphs,
69  * original codes or '?' as a last resort if replacement glyph is undefined
70  * by Adam Tla/lka <atlka@pg.gda.pl>, Aug 2006
71  */
72 
73 #include <linux/module.h>
74 #include <linux/types.h>
75 #include <linux/sched.h>
76 #include <linux/tty.h>
77 #include <linux/tty_flip.h>
78 #include <linux/kernel.h>
79 #include <linux/string.h>
80 #include <linux/errno.h>
81 #include <linux/kd.h>
82 #include <linux/slab.h>
83 #include <linux/major.h>
84 #include <linux/mm.h>
85 #include <linux/console.h>
86 #include <linux/init.h>
87 #include <linux/mutex.h>
88 #include <linux/vt_kern.h>
89 #include <linux/selection.h>
90 #include <linux/tiocl.h>
91 #include <linux/kbd_kern.h>
92 #include <linux/consolemap.h>
93 #include <linux/timer.h>
94 #include <linux/interrupt.h>
95 #include <linux/workqueue.h>
96 #include <linux/pm.h>
97 #include <linux/font.h>
98 #include <linux/bitops.h>
99 #include <linux/notifier.h>
100 #include <linux/device.h>
101 #include <linux/io.h>
102 #include <linux/uaccess.h>
103 #include <linux/kdb.h>
104 #include <linux/ctype.h>
105 
106 #define MAX_NR_CON_DRIVER 16
107 
108 #define CON_DRIVER_FLAG_MODULE 1
109 #define CON_DRIVER_FLAG_INIT   2
110 #define CON_DRIVER_FLAG_ATTR   4
111 #define CON_DRIVER_FLAG_ZOMBIE 8
112 
113 struct con_driver {
114 	const struct consw *con;
115 	const char *desc;
116 	struct device *dev;
117 	int node;
118 	int first;
119 	int last;
120 	int flag;
121 };
122 
123 static struct con_driver registered_con_driver[MAX_NR_CON_DRIVER];
124 const struct consw *conswitchp;
125 
126 /* A bitmap for codes <32. A bit of 1 indicates that the code
127  * corresponding to that bit number invokes some special action
128  * (such as cursor movement) and should not be displayed as a
129  * glyph unless the disp_ctrl mode is explicitly enabled.
130  */
131 #define CTRL_ACTION 0x0d00ff81
132 #define CTRL_ALWAYS 0x0800f501	/* Cannot be overridden by disp_ctrl */
133 
134 /*
135  * Here is the default bell parameters: 750HZ, 1/8th of a second
136  */
137 #define DEFAULT_BELL_PITCH	750
138 #define DEFAULT_BELL_DURATION	(HZ/8)
139 #define DEFAULT_CURSOR_BLINK_MS	200
140 
141 struct vc vc_cons [MAX_NR_CONSOLES];
142 
143 #ifndef VT_SINGLE_DRIVER
144 static const struct consw *con_driver_map[MAX_NR_CONSOLES];
145 #endif
146 
147 static int con_open(struct tty_struct *, struct file *);
148 static void vc_init(struct vc_data *vc, unsigned int rows,
149 		    unsigned int cols, int do_clear);
150 static void gotoxy(struct vc_data *vc, int new_x, int new_y);
151 static void save_cur(struct vc_data *vc);
152 static void reset_terminal(struct vc_data *vc, int do_clear);
153 static void con_flush_chars(struct tty_struct *tty);
154 static int set_vesa_blanking(char __user *p);
155 static void set_cursor(struct vc_data *vc);
156 static void hide_cursor(struct vc_data *vc);
157 static void console_callback(struct work_struct *ignored);
158 static void con_driver_unregister_callback(struct work_struct *ignored);
159 static void blank_screen_t(unsigned long dummy);
160 static void set_palette(struct vc_data *vc);
161 
162 #define vt_get_kmsg_redirect() vt_kmsg_redirect(-1)
163 
164 static int printable;		/* Is console ready for printing? */
165 int default_utf8 = true;
166 module_param(default_utf8, int, S_IRUGO | S_IWUSR);
167 int global_cursor_default = -1;
168 module_param(global_cursor_default, int, S_IRUGO | S_IWUSR);
169 
170 static int cur_default = CUR_DEFAULT;
171 module_param(cur_default, int, S_IRUGO | S_IWUSR);
172 
173 /*
174  * ignore_poke: don't unblank the screen when things are typed.  This is
175  * mainly for the privacy of braille terminal users.
176  */
177 static int ignore_poke;
178 
179 int do_poke_blanked_console;
180 int console_blanked;
181 
182 static int vesa_blank_mode; /* 0:none 1:suspendV 2:suspendH 3:powerdown */
183 static int vesa_off_interval;
184 static int blankinterval = 10*60;
185 core_param(consoleblank, blankinterval, int, 0444);
186 
187 static DECLARE_WORK(console_work, console_callback);
188 static DECLARE_WORK(con_driver_unregister_work, con_driver_unregister_callback);
189 
190 /*
191  * fg_console is the current virtual console,
192  * last_console is the last used one,
193  * want_console is the console we want to switch to,
194  * saved_* variants are for save/restore around kernel debugger enter/leave
195  */
196 int fg_console;
197 int last_console;
198 int want_console = -1;
199 static int saved_fg_console;
200 static int saved_last_console;
201 static int saved_want_console;
202 static int saved_vc_mode;
203 static int saved_console_blanked;
204 
205 /*
206  * For each existing display, we have a pointer to console currently visible
207  * on that display, allowing consoles other than fg_console to be refreshed
208  * appropriately. Unless the low-level driver supplies its own display_fg
209  * variable, we use this one for the "master display".
210  */
211 static struct vc_data *master_display_fg;
212 
213 /*
214  * Unfortunately, we need to delay tty echo when we're currently writing to the
215  * console since the code is (and always was) not re-entrant, so we schedule
216  * all flip requests to process context with schedule-task() and run it from
217  * console_callback().
218  */
219 
220 /*
221  * For the same reason, we defer scrollback to the console callback.
222  */
223 static int scrollback_delta;
224 
225 /*
226  * Hook so that the power management routines can (un)blank
227  * the console on our behalf.
228  */
229 int (*console_blank_hook)(int);
230 
231 static DEFINE_TIMER(console_timer, blank_screen_t, 0, 0);
232 static int blank_state;
233 static int blank_timer_expired;
234 enum {
235 	blank_off = 0,
236 	blank_normal_wait,
237 	blank_vesa_wait,
238 };
239 
240 /*
241  * /sys/class/tty/tty0/
242  *
243  * the attribute 'active' contains the name of the current vc
244  * console and it supports poll() to detect vc switches
245  */
246 static struct device *tty0dev;
247 
248 /*
249  * Notifier list for console events.
250  */
251 static ATOMIC_NOTIFIER_HEAD(vt_notifier_list);
252 
253 int register_vt_notifier(struct notifier_block *nb)
254 {
255 	return atomic_notifier_chain_register(&vt_notifier_list, nb);
256 }
257 EXPORT_SYMBOL_GPL(register_vt_notifier);
258 
259 int unregister_vt_notifier(struct notifier_block *nb)
260 {
261 	return atomic_notifier_chain_unregister(&vt_notifier_list, nb);
262 }
263 EXPORT_SYMBOL_GPL(unregister_vt_notifier);
264 
265 static void notify_write(struct vc_data *vc, unsigned int unicode)
266 {
267 	struct vt_notifier_param param = { .vc = vc, .c = unicode };
268 	atomic_notifier_call_chain(&vt_notifier_list, VT_WRITE, &param);
269 }
270 
271 static void notify_update(struct vc_data *vc)
272 {
273 	struct vt_notifier_param param = { .vc = vc };
274 	atomic_notifier_call_chain(&vt_notifier_list, VT_UPDATE, &param);
275 }
276 /*
277  *	Low-Level Functions
278  */
279 
280 static inline bool con_is_fg(const struct vc_data *vc)
281 {
282 	return vc->vc_num == fg_console;
283 }
284 
285 static inline bool con_should_update(const struct vc_data *vc)
286 {
287 	return con_is_visible(vc) && !console_blanked;
288 }
289 
290 static inline unsigned short *screenpos(struct vc_data *vc, int offset, int viewed)
291 {
292 	unsigned short *p;
293 
294 	if (!viewed)
295 		p = (unsigned short *)(vc->vc_origin + offset);
296 	else if (!vc->vc_sw->con_screen_pos)
297 		p = (unsigned short *)(vc->vc_visible_origin + offset);
298 	else
299 		p = vc->vc_sw->con_screen_pos(vc, offset);
300 	return p;
301 }
302 
303 /* Called  from the keyboard irq path.. */
304 static inline void scrolldelta(int lines)
305 {
306 	/* FIXME */
307 	/* scrolldelta needs some kind of consistency lock, but the BKL was
308 	   and still is not protecting versus the scheduled back end */
309 	scrollback_delta += lines;
310 	schedule_console_callback();
311 }
312 
313 void schedule_console_callback(void)
314 {
315 	schedule_work(&console_work);
316 }
317 
318 static void scrup(struct vc_data *vc, unsigned int t, unsigned int b, int nr)
319 {
320 	unsigned short *d, *s;
321 
322 	if (t+nr >= b)
323 		nr = b - t - 1;
324 	if (b > vc->vc_rows || t >= b || nr < 1)
325 		return;
326 	if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, t, b, SM_UP, nr))
327 		return;
328 	d = (unsigned short *)(vc->vc_origin + vc->vc_size_row * t);
329 	s = (unsigned short *)(vc->vc_origin + vc->vc_size_row * (t + nr));
330 	scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
331 	scr_memsetw(d + (b - t - nr) * vc->vc_cols, vc->vc_video_erase_char,
332 		    vc->vc_size_row * nr);
333 }
334 
335 static void scrdown(struct vc_data *vc, unsigned int t, unsigned int b, int nr)
336 {
337 	unsigned short *s;
338 	unsigned int step;
339 
340 	if (t+nr >= b)
341 		nr = b - t - 1;
342 	if (b > vc->vc_rows || t >= b || nr < 1)
343 		return;
344 	if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, t, b, SM_DOWN, nr))
345 		return;
346 	s = (unsigned short *)(vc->vc_origin + vc->vc_size_row * t);
347 	step = vc->vc_cols * nr;
348 	scr_memmovew(s + step, s, (b - t - nr) * vc->vc_size_row);
349 	scr_memsetw(s, vc->vc_video_erase_char, 2 * step);
350 }
351 
352 static void do_update_region(struct vc_data *vc, unsigned long start, int count)
353 {
354 	unsigned int xx, yy, offset;
355 	u16 *p;
356 
357 	p = (u16 *) start;
358 	if (!vc->vc_sw->con_getxy) {
359 		offset = (start - vc->vc_origin) / 2;
360 		xx = offset % vc->vc_cols;
361 		yy = offset / vc->vc_cols;
362 	} else {
363 		int nxx, nyy;
364 		start = vc->vc_sw->con_getxy(vc, start, &nxx, &nyy);
365 		xx = nxx; yy = nyy;
366 	}
367 	for(;;) {
368 		u16 attrib = scr_readw(p) & 0xff00;
369 		int startx = xx;
370 		u16 *q = p;
371 		while (xx < vc->vc_cols && count) {
372 			if (attrib != (scr_readw(p) & 0xff00)) {
373 				if (p > q)
374 					vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
375 				startx = xx;
376 				q = p;
377 				attrib = scr_readw(p) & 0xff00;
378 			}
379 			p++;
380 			xx++;
381 			count--;
382 		}
383 		if (p > q)
384 			vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
385 		if (!count)
386 			break;
387 		xx = 0;
388 		yy++;
389 		if (vc->vc_sw->con_getxy) {
390 			p = (u16 *)start;
391 			start = vc->vc_sw->con_getxy(vc, start, NULL, NULL);
392 		}
393 	}
394 }
395 
396 void update_region(struct vc_data *vc, unsigned long start, int count)
397 {
398 	WARN_CONSOLE_UNLOCKED();
399 
400 	if (con_should_update(vc)) {
401 		hide_cursor(vc);
402 		do_update_region(vc, start, count);
403 		set_cursor(vc);
404 	}
405 }
406 
407 /* Structure of attributes is hardware-dependent */
408 
409 static u8 build_attr(struct vc_data *vc, u8 _color, u8 _intensity, u8 _blink,
410     u8 _underline, u8 _reverse, u8 _italic)
411 {
412 	if (vc->vc_sw->con_build_attr)
413 		return vc->vc_sw->con_build_attr(vc, _color, _intensity,
414 		       _blink, _underline, _reverse, _italic);
415 
416 /*
417  * ++roman: I completely changed the attribute format for monochrome
418  * mode (!can_do_color). The formerly used MDA (monochrome display
419  * adapter) format didn't allow the combination of certain effects.
420  * Now the attribute is just a bit vector:
421  *  Bit 0..1: intensity (0..2)
422  *  Bit 2   : underline
423  *  Bit 3   : reverse
424  *  Bit 7   : blink
425  */
426 	{
427 	u8 a = _color;
428 	if (!vc->vc_can_do_color)
429 		return _intensity |
430 		       (_italic ? 2 : 0) |
431 		       (_underline ? 4 : 0) |
432 		       (_reverse ? 8 : 0) |
433 		       (_blink ? 0x80 : 0);
434 	if (_italic)
435 		a = (a & 0xF0) | vc->vc_itcolor;
436 	else if (_underline)
437 		a = (a & 0xf0) | vc->vc_ulcolor;
438 	else if (_intensity == 0)
439 		a = (a & 0xf0) | vc->vc_ulcolor;
440 	if (_reverse)
441 		a = ((a) & 0x88) | ((((a) >> 4) | ((a) << 4)) & 0x77);
442 	if (_blink)
443 		a ^= 0x80;
444 	if (_intensity == 2)
445 		a ^= 0x08;
446 	if (vc->vc_hi_font_mask == 0x100)
447 		a <<= 1;
448 	return a;
449 	}
450 }
451 
452 static void update_attr(struct vc_data *vc)
453 {
454 	vc->vc_attr = build_attr(vc, vc->vc_color, vc->vc_intensity,
455 	              vc->vc_blink, vc->vc_underline,
456 	              vc->vc_reverse ^ vc->vc_decscnm, vc->vc_italic);
457 	vc->vc_video_erase_char = (build_attr(vc, vc->vc_color, 1, vc->vc_blink, 0, vc->vc_decscnm, 0) << 8) | ' ';
458 }
459 
460 /* Note: inverting the screen twice should revert to the original state */
461 void invert_screen(struct vc_data *vc, int offset, int count, int viewed)
462 {
463 	unsigned short *p;
464 
465 	WARN_CONSOLE_UNLOCKED();
466 
467 	count /= 2;
468 	p = screenpos(vc, offset, viewed);
469 	if (vc->vc_sw->con_invert_region) {
470 		vc->vc_sw->con_invert_region(vc, p, count);
471 	} else {
472 		u16 *q = p;
473 		int cnt = count;
474 		u16 a;
475 
476 		if (!vc->vc_can_do_color) {
477 			while (cnt--) {
478 			    a = scr_readw(q);
479 			    a ^= 0x0800;
480 			    scr_writew(a, q);
481 			    q++;
482 			}
483 		} else if (vc->vc_hi_font_mask == 0x100) {
484 			while (cnt--) {
485 				a = scr_readw(q);
486 				a = ((a) & 0x11ff) | (((a) & 0xe000) >> 4) | (((a) & 0x0e00) << 4);
487 				scr_writew(a, q);
488 				q++;
489 			}
490 		} else {
491 			while (cnt--) {
492 				a = scr_readw(q);
493 				a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) | (((a) & 0x0700) << 4);
494 				scr_writew(a, q);
495 				q++;
496 			}
497 		}
498 	}
499 
500 	if (con_should_update(vc))
501 		do_update_region(vc, (unsigned long) p, count);
502 	notify_update(vc);
503 }
504 
505 /* used by selection: complement pointer position */
506 void complement_pos(struct vc_data *vc, int offset)
507 {
508 	static int old_offset = -1;
509 	static unsigned short old;
510 	static unsigned short oldx, oldy;
511 
512 	WARN_CONSOLE_UNLOCKED();
513 
514 	if (old_offset != -1 && old_offset >= 0 &&
515 	    old_offset < vc->vc_screenbuf_size) {
516 		scr_writew(old, screenpos(vc, old_offset, 1));
517 		if (con_should_update(vc))
518 			vc->vc_sw->con_putc(vc, old, oldy, oldx);
519 		notify_update(vc);
520 	}
521 
522 	old_offset = offset;
523 
524 	if (offset != -1 && offset >= 0 &&
525 	    offset < vc->vc_screenbuf_size) {
526 		unsigned short new;
527 		unsigned short *p;
528 		p = screenpos(vc, offset, 1);
529 		old = scr_readw(p);
530 		new = old ^ vc->vc_complement_mask;
531 		scr_writew(new, p);
532 		if (con_should_update(vc)) {
533 			oldx = (offset >> 1) % vc->vc_cols;
534 			oldy = (offset >> 1) / vc->vc_cols;
535 			vc->vc_sw->con_putc(vc, new, oldy, oldx);
536 		}
537 		notify_update(vc);
538 	}
539 }
540 
541 static void insert_char(struct vc_data *vc, unsigned int nr)
542 {
543 	unsigned short *p = (unsigned short *) vc->vc_pos;
544 
545 	scr_memmovew(p + nr, p, (vc->vc_cols - vc->vc_x - nr) * 2);
546 	scr_memsetw(p, vc->vc_video_erase_char, nr * 2);
547 	vc->vc_need_wrap = 0;
548 	if (con_should_update(vc))
549 		do_update_region(vc, (unsigned long) p,
550 			vc->vc_cols - vc->vc_x);
551 }
552 
553 static void delete_char(struct vc_data *vc, unsigned int nr)
554 {
555 	unsigned short *p = (unsigned short *) vc->vc_pos;
556 
557 	scr_memcpyw(p, p + nr, (vc->vc_cols - vc->vc_x - nr) * 2);
558 	scr_memsetw(p + vc->vc_cols - vc->vc_x - nr, vc->vc_video_erase_char,
559 			nr * 2);
560 	vc->vc_need_wrap = 0;
561 	if (con_should_update(vc))
562 		do_update_region(vc, (unsigned long) p,
563 			vc->vc_cols - vc->vc_x);
564 }
565 
566 static int softcursor_original = -1;
567 
568 static void add_softcursor(struct vc_data *vc)
569 {
570 	int i = scr_readw((u16 *) vc->vc_pos);
571 	u32 type = vc->vc_cursor_type;
572 
573 	if (! (type & 0x10)) return;
574 	if (softcursor_original != -1) return;
575 	softcursor_original = i;
576 	i |= ((type >> 8) & 0xff00 );
577 	i ^= ((type) & 0xff00 );
578 	if ((type & 0x20) && ((softcursor_original & 0x7000) == (i & 0x7000))) i ^= 0x7000;
579 	if ((type & 0x40) && ((i & 0x700) == ((i & 0x7000) >> 4))) i ^= 0x0700;
580 	scr_writew(i, (u16 *) vc->vc_pos);
581 	if (con_should_update(vc))
582 		vc->vc_sw->con_putc(vc, i, vc->vc_y, vc->vc_x);
583 }
584 
585 static void hide_softcursor(struct vc_data *vc)
586 {
587 	if (softcursor_original != -1) {
588 		scr_writew(softcursor_original, (u16 *)vc->vc_pos);
589 		if (con_should_update(vc))
590 			vc->vc_sw->con_putc(vc, softcursor_original,
591 					vc->vc_y, vc->vc_x);
592 		softcursor_original = -1;
593 	}
594 }
595 
596 static void hide_cursor(struct vc_data *vc)
597 {
598 	if (vc == sel_cons)
599 		clear_selection();
600 	vc->vc_sw->con_cursor(vc, CM_ERASE);
601 	hide_softcursor(vc);
602 }
603 
604 static void set_cursor(struct vc_data *vc)
605 {
606 	if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS)
607 		return;
608 	if (vc->vc_deccm) {
609 		if (vc == sel_cons)
610 			clear_selection();
611 		add_softcursor(vc);
612 		if ((vc->vc_cursor_type & 0x0f) != 1)
613 			vc->vc_sw->con_cursor(vc, CM_DRAW);
614 	} else
615 		hide_cursor(vc);
616 }
617 
618 static void set_origin(struct vc_data *vc)
619 {
620 	WARN_CONSOLE_UNLOCKED();
621 
622 	if (!con_is_visible(vc) ||
623 	    !vc->vc_sw->con_set_origin ||
624 	    !vc->vc_sw->con_set_origin(vc))
625 		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
626 	vc->vc_visible_origin = vc->vc_origin;
627 	vc->vc_scr_end = vc->vc_origin + vc->vc_screenbuf_size;
628 	vc->vc_pos = vc->vc_origin + vc->vc_size_row * vc->vc_y + 2 * vc->vc_x;
629 }
630 
631 static void save_screen(struct vc_data *vc)
632 {
633 	WARN_CONSOLE_UNLOCKED();
634 
635 	if (vc->vc_sw->con_save_screen)
636 		vc->vc_sw->con_save_screen(vc);
637 }
638 
639 /*
640  *	Redrawing of screen
641  */
642 
643 void clear_buffer_attributes(struct vc_data *vc)
644 {
645 	unsigned short *p = (unsigned short *)vc->vc_origin;
646 	int count = vc->vc_screenbuf_size / 2;
647 	int mask = vc->vc_hi_font_mask | 0xff;
648 
649 	for (; count > 0; count--, p++) {
650 		scr_writew((scr_readw(p)&mask) | (vc->vc_video_erase_char & ~mask), p);
651 	}
652 }
653 
654 void redraw_screen(struct vc_data *vc, int is_switch)
655 {
656 	int redraw = 0;
657 
658 	WARN_CONSOLE_UNLOCKED();
659 
660 	if (!vc) {
661 		/* strange ... */
662 		/* printk("redraw_screen: tty %d not allocated ??\n", new_console+1); */
663 		return;
664 	}
665 
666 	if (is_switch) {
667 		struct vc_data *old_vc = vc_cons[fg_console].d;
668 		if (old_vc == vc)
669 			return;
670 		if (!con_is_visible(vc))
671 			redraw = 1;
672 		*vc->vc_display_fg = vc;
673 		fg_console = vc->vc_num;
674 		hide_cursor(old_vc);
675 		if (!con_is_visible(old_vc)) {
676 			save_screen(old_vc);
677 			set_origin(old_vc);
678 		}
679 		if (tty0dev)
680 			sysfs_notify(&tty0dev->kobj, NULL, "active");
681 	} else {
682 		hide_cursor(vc);
683 		redraw = 1;
684 	}
685 
686 	if (redraw) {
687 		int update;
688 		int old_was_color = vc->vc_can_do_color;
689 
690 		set_origin(vc);
691 		update = vc->vc_sw->con_switch(vc);
692 		set_palette(vc);
693 		/*
694 		 * If console changed from mono<->color, the best we can do
695 		 * is to clear the buffer attributes. As it currently stands,
696 		 * rebuilding new attributes from the old buffer is not doable
697 		 * without overly complex code.
698 		 */
699 		if (old_was_color != vc->vc_can_do_color) {
700 			update_attr(vc);
701 			clear_buffer_attributes(vc);
702 		}
703 
704 		/* Forcibly update if we're panicing */
705 		if ((update && vc->vc_mode != KD_GRAPHICS) ||
706 		    vt_force_oops_output(vc))
707 			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
708 	}
709 	set_cursor(vc);
710 	if (is_switch) {
711 		set_leds();
712 		compute_shiftstate();
713 		notify_update(vc);
714 	}
715 }
716 
717 /*
718  *	Allocation, freeing and resizing of VTs.
719  */
720 
721 int vc_cons_allocated(unsigned int i)
722 {
723 	return (i < MAX_NR_CONSOLES && vc_cons[i].d);
724 }
725 
726 static void visual_init(struct vc_data *vc, int num, int init)
727 {
728 	/* ++Geert: vc->vc_sw->con_init determines console size */
729 	if (vc->vc_sw)
730 		module_put(vc->vc_sw->owner);
731 	vc->vc_sw = conswitchp;
732 #ifndef VT_SINGLE_DRIVER
733 	if (con_driver_map[num])
734 		vc->vc_sw = con_driver_map[num];
735 #endif
736 	__module_get(vc->vc_sw->owner);
737 	vc->vc_num = num;
738 	vc->vc_display_fg = &master_display_fg;
739 	if (vc->vc_uni_pagedir_loc)
740 		con_free_unimap(vc);
741 	vc->vc_uni_pagedir_loc = &vc->vc_uni_pagedir;
742 	vc->vc_uni_pagedir = NULL;
743 	vc->vc_hi_font_mask = 0;
744 	vc->vc_complement_mask = 0;
745 	vc->vc_can_do_color = 0;
746 	vc->vc_panic_force_write = false;
747 	vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
748 	vc->vc_sw->con_init(vc, init);
749 	if (!vc->vc_complement_mask)
750 		vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
751 	vc->vc_s_complement_mask = vc->vc_complement_mask;
752 	vc->vc_size_row = vc->vc_cols << 1;
753 	vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
754 }
755 
756 int vc_allocate(unsigned int currcons)	/* return 0 on success */
757 {
758 	struct vt_notifier_param param;
759 	struct vc_data *vc;
760 
761 	WARN_CONSOLE_UNLOCKED();
762 
763 	if (currcons >= MAX_NR_CONSOLES)
764 		return -ENXIO;
765 
766 	if (vc_cons[currcons].d)
767 		return 0;
768 
769 	/* due to the granularity of kmalloc, we waste some memory here */
770 	/* the alloc is done in two steps, to optimize the common situation
771 	   of a 25x80 console (structsize=216, screenbuf_size=4000) */
772 	/* although the numbers above are not valid since long ago, the
773 	   point is still up-to-date and the comment still has its value
774 	   even if only as a historical artifact.  --mj, July 1998 */
775 	param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL);
776 	if (!vc)
777 		return -ENOMEM;
778 
779 	vc_cons[currcons].d = vc;
780 	tty_port_init(&vc->port);
781 	INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
782 
783 	visual_init(vc, currcons, 1);
784 
785 	if (!*vc->vc_uni_pagedir_loc)
786 		con_set_default_unimap(vc);
787 
788 	vc->vc_screenbuf = kmalloc(vc->vc_screenbuf_size, GFP_KERNEL);
789 	if (!vc->vc_screenbuf)
790 		goto err_free;
791 
792 	/* If no drivers have overridden us and the user didn't pass a
793 	   boot option, default to displaying the cursor */
794 	if (global_cursor_default == -1)
795 		global_cursor_default = 1;
796 
797 	vc_init(vc, vc->vc_rows, vc->vc_cols, 1);
798 	vcs_make_sysfs(currcons);
799 	atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, &param);
800 
801 	return 0;
802 err_free:
803 	kfree(vc);
804 	vc_cons[currcons].d = NULL;
805 	return -ENOMEM;
806 }
807 
808 static inline int resize_screen(struct vc_data *vc, int width, int height,
809 				int user)
810 {
811 	/* Resizes the resolution of the display adapater */
812 	int err = 0;
813 
814 	if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_resize)
815 		err = vc->vc_sw->con_resize(vc, width, height, user);
816 
817 	return err;
818 }
819 
820 /*
821  * Change # of rows and columns (0 means unchanged/the size of fg_console)
822  * [this is to be used together with some user program
823  * like resize that changes the hardware videomode]
824  */
825 #define VC_RESIZE_MAXCOL (32767)
826 #define VC_RESIZE_MAXROW (32767)
827 
828 /**
829  *	vc_do_resize	-	resizing method for the tty
830  *	@tty: tty being resized
831  *	@real_tty: real tty (different to tty if a pty/tty pair)
832  *	@vc: virtual console private data
833  *	@cols: columns
834  *	@lines: lines
835  *
836  *	Resize a virtual console, clipping according to the actual constraints.
837  *	If the caller passes a tty structure then update the termios winsize
838  *	information and perform any necessary signal handling.
839  *
840  *	Caller must hold the console semaphore. Takes the termios rwsem and
841  *	ctrl_lock of the tty IFF a tty is passed.
842  */
843 
844 static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
845 				unsigned int cols, unsigned int lines)
846 {
847 	unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
848 	unsigned long end;
849 	unsigned int old_rows, old_row_size;
850 	unsigned int new_cols, new_rows, new_row_size, new_screen_size;
851 	unsigned int user;
852 	unsigned short *newscreen;
853 
854 	WARN_CONSOLE_UNLOCKED();
855 
856 	if (!vc)
857 		return -ENXIO;
858 
859 	user = vc->vc_resize_user;
860 	vc->vc_resize_user = 0;
861 
862 	if (cols > VC_RESIZE_MAXCOL || lines > VC_RESIZE_MAXROW)
863 		return -EINVAL;
864 
865 	new_cols = (cols ? cols : vc->vc_cols);
866 	new_rows = (lines ? lines : vc->vc_rows);
867 	new_row_size = new_cols << 1;
868 	new_screen_size = new_row_size * new_rows;
869 
870 	if (new_cols == vc->vc_cols && new_rows == vc->vc_rows)
871 		return 0;
872 
873 	if (new_screen_size > (4 << 20))
874 		return -EINVAL;
875 	newscreen = kmalloc(new_screen_size, GFP_USER);
876 	if (!newscreen)
877 		return -ENOMEM;
878 
879 	if (vc == sel_cons)
880 		clear_selection();
881 
882 	old_rows = vc->vc_rows;
883 	old_row_size = vc->vc_size_row;
884 
885 	err = resize_screen(vc, new_cols, new_rows, user);
886 	if (err) {
887 		kfree(newscreen);
888 		return err;
889 	}
890 
891 	vc->vc_rows = new_rows;
892 	vc->vc_cols = new_cols;
893 	vc->vc_size_row = new_row_size;
894 	vc->vc_screenbuf_size = new_screen_size;
895 
896 	rlth = min(old_row_size, new_row_size);
897 	rrem = new_row_size - rlth;
898 	old_origin = vc->vc_origin;
899 	new_origin = (long) newscreen;
900 	new_scr_end = new_origin + new_screen_size;
901 
902 	if (vc->vc_y > new_rows) {
903 		if (old_rows - vc->vc_y < new_rows) {
904 			/*
905 			 * Cursor near the bottom, copy contents from the
906 			 * bottom of buffer
907 			 */
908 			old_origin += (old_rows - new_rows) * old_row_size;
909 		} else {
910 			/*
911 			 * Cursor is in no man's land, copy 1/2 screenful
912 			 * from the top and bottom of cursor position
913 			 */
914 			old_origin += (vc->vc_y - new_rows/2) * old_row_size;
915 		}
916 	}
917 
918 	end = old_origin + old_row_size * min(old_rows, new_rows);
919 
920 	update_attr(vc);
921 
922 	while (old_origin < end) {
923 		scr_memcpyw((unsigned short *) new_origin,
924 			    (unsigned short *) old_origin, rlth);
925 		if (rrem)
926 			scr_memsetw((void *)(new_origin + rlth),
927 				    vc->vc_video_erase_char, rrem);
928 		old_origin += old_row_size;
929 		new_origin += new_row_size;
930 	}
931 	if (new_scr_end > new_origin)
932 		scr_memsetw((void *)new_origin, vc->vc_video_erase_char,
933 			    new_scr_end - new_origin);
934 	kfree(vc->vc_screenbuf);
935 	vc->vc_screenbuf = newscreen;
936 	vc->vc_screenbuf_size = new_screen_size;
937 	set_origin(vc);
938 
939 	/* do part of a reset_terminal() */
940 	vc->vc_top = 0;
941 	vc->vc_bottom = vc->vc_rows;
942 	gotoxy(vc, vc->vc_x, vc->vc_y);
943 	save_cur(vc);
944 
945 	if (tty) {
946 		/* Rewrite the requested winsize data with the actual
947 		   resulting sizes */
948 		struct winsize ws;
949 		memset(&ws, 0, sizeof(ws));
950 		ws.ws_row = vc->vc_rows;
951 		ws.ws_col = vc->vc_cols;
952 		ws.ws_ypixel = vc->vc_scan_lines;
953 		tty_do_resize(tty, &ws);
954 	}
955 
956 	if (con_is_visible(vc))
957 		update_screen(vc);
958 	vt_event_post(VT_EVENT_RESIZE, vc->vc_num, vc->vc_num);
959 	return err;
960 }
961 
962 /**
963  *	vc_resize		-	resize a VT
964  *	@vc: virtual console
965  *	@cols: columns
966  *	@rows: rows
967  *
968  *	Resize a virtual console as seen from the console end of things. We
969  *	use the common vc_do_resize methods to update the structures. The
970  *	caller must hold the console sem to protect console internals and
971  *	vc->port.tty
972  */
973 
974 int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
975 {
976 	return vc_do_resize(vc->port.tty, vc, cols, rows);
977 }
978 
979 /**
980  *	vt_resize		-	resize a VT
981  *	@tty: tty to resize
982  *	@ws: winsize attributes
983  *
984  *	Resize a virtual terminal. This is called by the tty layer as we
985  *	register our own handler for resizing. The mutual helper does all
986  *	the actual work.
987  *
988  *	Takes the console sem and the called methods then take the tty
989  *	termios_rwsem and the tty ctrl_lock in that order.
990  */
991 static int vt_resize(struct tty_struct *tty, struct winsize *ws)
992 {
993 	struct vc_data *vc = tty->driver_data;
994 	int ret;
995 
996 	console_lock();
997 	ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row);
998 	console_unlock();
999 	return ret;
1000 }
1001 
1002 struct vc_data *vc_deallocate(unsigned int currcons)
1003 {
1004 	struct vc_data *vc = NULL;
1005 
1006 	WARN_CONSOLE_UNLOCKED();
1007 
1008 	if (vc_cons_allocated(currcons)) {
1009 		struct vt_notifier_param param;
1010 
1011 		param.vc = vc = vc_cons[currcons].d;
1012 		atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, &param);
1013 		vcs_remove_sysfs(currcons);
1014 		vc->vc_sw->con_deinit(vc);
1015 		put_pid(vc->vt_pid);
1016 		module_put(vc->vc_sw->owner);
1017 		kfree(vc->vc_screenbuf);
1018 		vc_cons[currcons].d = NULL;
1019 	}
1020 	return vc;
1021 }
1022 
1023 /*
1024  *	VT102 emulator
1025  */
1026 
1027 #define set_kbd(vc, x)	vt_set_kbd_mode_bit((vc)->vc_num, (x))
1028 #define clr_kbd(vc, x)	vt_clr_kbd_mode_bit((vc)->vc_num, (x))
1029 #define is_kbd(vc, x)	vt_get_kbd_mode_bit((vc)->vc_num, (x))
1030 
1031 #define decarm		VC_REPEAT
1032 #define decckm		VC_CKMODE
1033 #define kbdapplic	VC_APPLIC
1034 #define lnm		VC_CRLF
1035 
1036 /*
1037  * this is what the terminal answers to a ESC-Z or csi0c query.
1038  */
1039 #define VT100ID "\033[?1;2c"
1040 #define VT102ID "\033[?6c"
1041 
1042 const unsigned char color_table[] = { 0, 4, 2, 6, 1, 5, 3, 7,
1043 				       8,12,10,14, 9,13,11,15 };
1044 
1045 /* the default colour table, for VGA+ colour systems */
1046 unsigned char default_red[] = {
1047 	0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa,
1048 	0x55, 0xff, 0x55, 0xff, 0x55, 0xff, 0x55, 0xff
1049 };
1050 module_param_array(default_red, byte, NULL, S_IRUGO | S_IWUSR);
1051 
1052 unsigned char default_grn[] = {
1053 	0x00, 0x00, 0xaa, 0x55, 0x00, 0x00, 0xaa, 0xaa,
1054 	0x55, 0x55, 0xff, 0xff, 0x55, 0x55, 0xff, 0xff
1055 };
1056 module_param_array(default_grn, byte, NULL, S_IRUGO | S_IWUSR);
1057 
1058 unsigned char default_blu[] = {
1059 	0x00, 0x00, 0x00, 0x00, 0xaa, 0xaa, 0xaa, 0xaa,
1060 	0x55, 0x55, 0x55, 0x55, 0xff, 0xff, 0xff, 0xff
1061 };
1062 module_param_array(default_blu, byte, NULL, S_IRUGO | S_IWUSR);
1063 
1064 /*
1065  * gotoxy() must verify all boundaries, because the arguments
1066  * might also be negative. If the given position is out of
1067  * bounds, the cursor is placed at the nearest margin.
1068  */
1069 static void gotoxy(struct vc_data *vc, int new_x, int new_y)
1070 {
1071 	int min_y, max_y;
1072 
1073 	if (new_x < 0)
1074 		vc->vc_x = 0;
1075 	else {
1076 		if (new_x >= vc->vc_cols)
1077 			vc->vc_x = vc->vc_cols - 1;
1078 		else
1079 			vc->vc_x = new_x;
1080 	}
1081 
1082  	if (vc->vc_decom) {
1083 		min_y = vc->vc_top;
1084 		max_y = vc->vc_bottom;
1085 	} else {
1086 		min_y = 0;
1087 		max_y = vc->vc_rows;
1088 	}
1089 	if (new_y < min_y)
1090 		vc->vc_y = min_y;
1091 	else if (new_y >= max_y)
1092 		vc->vc_y = max_y - 1;
1093 	else
1094 		vc->vc_y = new_y;
1095 	vc->vc_pos = vc->vc_origin + vc->vc_y * vc->vc_size_row + (vc->vc_x<<1);
1096 	vc->vc_need_wrap = 0;
1097 }
1098 
1099 /* for absolute user moves, when decom is set */
1100 static void gotoxay(struct vc_data *vc, int new_x, int new_y)
1101 {
1102 	gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y);
1103 }
1104 
1105 void scrollback(struct vc_data *vc)
1106 {
1107 	scrolldelta(-(vc->vc_rows / 2));
1108 }
1109 
1110 void scrollfront(struct vc_data *vc, int lines)
1111 {
1112 	if (!lines)
1113 		lines = vc->vc_rows / 2;
1114 	scrolldelta(lines);
1115 }
1116 
1117 static void lf(struct vc_data *vc)
1118 {
1119     	/* don't scroll if above bottom of scrolling region, or
1120 	 * if below scrolling region
1121 	 */
1122     	if (vc->vc_y + 1 == vc->vc_bottom)
1123 		scrup(vc, vc->vc_top, vc->vc_bottom, 1);
1124 	else if (vc->vc_y < vc->vc_rows - 1) {
1125 	    	vc->vc_y++;
1126 		vc->vc_pos += vc->vc_size_row;
1127 	}
1128 	vc->vc_need_wrap = 0;
1129 	notify_write(vc, '\n');
1130 }
1131 
1132 static void ri(struct vc_data *vc)
1133 {
1134     	/* don't scroll if below top of scrolling region, or
1135 	 * if above scrolling region
1136 	 */
1137 	if (vc->vc_y == vc->vc_top)
1138 		scrdown(vc, vc->vc_top, vc->vc_bottom, 1);
1139 	else if (vc->vc_y > 0) {
1140 		vc->vc_y--;
1141 		vc->vc_pos -= vc->vc_size_row;
1142 	}
1143 	vc->vc_need_wrap = 0;
1144 }
1145 
1146 static inline void cr(struct vc_data *vc)
1147 {
1148 	vc->vc_pos -= vc->vc_x << 1;
1149 	vc->vc_need_wrap = vc->vc_x = 0;
1150 	notify_write(vc, '\r');
1151 }
1152 
1153 static inline void bs(struct vc_data *vc)
1154 {
1155 	if (vc->vc_x) {
1156 		vc->vc_pos -= 2;
1157 		vc->vc_x--;
1158 		vc->vc_need_wrap = 0;
1159 		notify_write(vc, '\b');
1160 	}
1161 }
1162 
1163 static inline void del(struct vc_data *vc)
1164 {
1165 	/* ignored */
1166 }
1167 
1168 static void csi_J(struct vc_data *vc, int vpar)
1169 {
1170 	unsigned int count;
1171 	unsigned short * start;
1172 
1173 	switch (vpar) {
1174 		case 0:	/* erase from cursor to end of display */
1175 			count = (vc->vc_scr_end - vc->vc_pos) >> 1;
1176 			start = (unsigned short *)vc->vc_pos;
1177 			break;
1178 		case 1:	/* erase from start to cursor */
1179 			count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1;
1180 			start = (unsigned short *)vc->vc_origin;
1181 			break;
1182 		case 3: /* erase scroll-back buffer (and whole display) */
1183 			scr_memsetw(vc->vc_screenbuf, vc->vc_video_erase_char,
1184 				    vc->vc_screenbuf_size);
1185 			set_origin(vc);
1186 			if (con_is_visible(vc))
1187 				update_screen(vc);
1188 			/* fall through */
1189 		case 2: /* erase whole display */
1190 			count = vc->vc_cols * vc->vc_rows;
1191 			start = (unsigned short *)vc->vc_origin;
1192 			break;
1193 		default:
1194 			return;
1195 	}
1196 	scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1197 	if (con_should_update(vc))
1198 		do_update_region(vc, (unsigned long) start, count);
1199 	vc->vc_need_wrap = 0;
1200 }
1201 
1202 static void csi_K(struct vc_data *vc, int vpar)
1203 {
1204 	unsigned int count;
1205 	unsigned short * start;
1206 
1207 	switch (vpar) {
1208 		case 0:	/* erase from cursor to end of line */
1209 			count = vc->vc_cols - vc->vc_x;
1210 			start = (unsigned short *)vc->vc_pos;
1211 			break;
1212 		case 1:	/* erase from start of line to cursor */
1213 			start = (unsigned short *)(vc->vc_pos - (vc->vc_x << 1));
1214 			count = vc->vc_x + 1;
1215 			break;
1216 		case 2: /* erase whole line */
1217 			start = (unsigned short *)(vc->vc_pos - (vc->vc_x << 1));
1218 			count = vc->vc_cols;
1219 			break;
1220 		default:
1221 			return;
1222 	}
1223 	scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1224 	vc->vc_need_wrap = 0;
1225 	if (con_should_update(vc))
1226 		do_update_region(vc, (unsigned long) start, count);
1227 }
1228 
1229 static void csi_X(struct vc_data *vc, int vpar) /* erase the following vpar positions */
1230 {					  /* not vt100? */
1231 	int count;
1232 
1233 	if (!vpar)
1234 		vpar++;
1235 	count = (vpar > vc->vc_cols - vc->vc_x) ? (vc->vc_cols - vc->vc_x) : vpar;
1236 
1237 	scr_memsetw((unsigned short *)vc->vc_pos, vc->vc_video_erase_char, 2 * count);
1238 	if (con_should_update(vc))
1239 		vc->vc_sw->con_clear(vc, vc->vc_y, vc->vc_x, 1, count);
1240 	vc->vc_need_wrap = 0;
1241 }
1242 
1243 static void default_attr(struct vc_data *vc)
1244 {
1245 	vc->vc_intensity = 1;
1246 	vc->vc_italic = 0;
1247 	vc->vc_underline = 0;
1248 	vc->vc_reverse = 0;
1249 	vc->vc_blink = 0;
1250 	vc->vc_color = vc->vc_def_color;
1251 }
1252 
1253 struct rgb { u8 r; u8 g; u8 b; };
1254 
1255 static void rgb_from_256(int i, struct rgb *c)
1256 {
1257 	if (i < 8) {            /* Standard colours. */
1258 		c->r = i&1 ? 0xaa : 0x00;
1259 		c->g = i&2 ? 0xaa : 0x00;
1260 		c->b = i&4 ? 0xaa : 0x00;
1261 	} else if (i < 16) {
1262 		c->r = i&1 ? 0xff : 0x55;
1263 		c->g = i&2 ? 0xff : 0x55;
1264 		c->b = i&4 ? 0xff : 0x55;
1265 	} else if (i < 232) {   /* 6x6x6 colour cube. */
1266 		c->r = (i - 16) / 36 * 85 / 2;
1267 		c->g = (i - 16) / 6 % 6 * 85 / 2;
1268 		c->b = (i - 16) % 6 * 85 / 2;
1269 	} else                  /* Grayscale ramp. */
1270 		c->r = c->g = c->b = i * 10 - 2312;
1271 }
1272 
1273 static void rgb_foreground(struct vc_data *vc, const struct rgb *c)
1274 {
1275 	u8 hue = 0, max = max3(c->r, c->g, c->b);
1276 
1277 	if (c->r > max / 2)
1278 		hue |= 4;
1279 	if (c->g > max / 2)
1280 		hue |= 2;
1281 	if (c->b > max / 2)
1282 		hue |= 1;
1283 
1284 	if (hue == 7 && max <= 0x55) {
1285 		hue = 0;
1286 		vc->vc_intensity = 2;
1287 	} else if (max > 0xaa)
1288 		vc->vc_intensity = 2;
1289 	else
1290 		vc->vc_intensity = 1;
1291 
1292 	vc->vc_color = (vc->vc_color & 0xf0) | hue;
1293 }
1294 
1295 static void rgb_background(struct vc_data *vc, const struct rgb *c)
1296 {
1297 	/* For backgrounds, err on the dark side. */
1298 	vc->vc_color = (vc->vc_color & 0x0f)
1299 		| (c->r&0x80) >> 1 | (c->g&0x80) >> 2 | (c->b&0x80) >> 3;
1300 }
1301 
1302 /*
1303  * ITU T.416 Higher colour modes. They break the usual properties of SGR codes
1304  * and thus need to be detected and ignored by hand. Strictly speaking, that
1305  * standard also wants : rather than ; as separators, contrary to ECMA-48, but
1306  * no one produces such codes and almost no one accepts them.
1307  *
1308  * Subcommands 3 (CMY) and 4 (CMYK) are so insane there's no point in
1309  * supporting them.
1310  */
1311 static int vc_t416_color(struct vc_data *vc, int i,
1312 		void(*set_color)(struct vc_data *vc, const struct rgb *c))
1313 {
1314 	struct rgb c;
1315 
1316 	i++;
1317 	if (i > vc->vc_npar)
1318 		return i;
1319 
1320 	if (vc->vc_par[i] == 5 && i + 1 <= vc->vc_npar) {
1321 		/* 256 colours */
1322 		i++;
1323 		rgb_from_256(vc->vc_par[i], &c);
1324 	} else if (vc->vc_par[i] == 2 && i + 3 <= vc->vc_npar) {
1325 		/* 24 bit */
1326 		c.r = vc->vc_par[i + 1];
1327 		c.g = vc->vc_par[i + 2];
1328 		c.b = vc->vc_par[i + 3];
1329 		i += 3;
1330 	} else
1331 		return i;
1332 
1333 	set_color(vc, &c);
1334 
1335 	return i;
1336 }
1337 
1338 /* console_lock is held */
1339 static void csi_m(struct vc_data *vc)
1340 {
1341 	int i;
1342 
1343 	for (i = 0; i <= vc->vc_npar; i++)
1344 		switch (vc->vc_par[i]) {
1345 		case 0:	/* all attributes off */
1346 			default_attr(vc);
1347 			break;
1348 		case 1:
1349 			vc->vc_intensity = 2;
1350 			break;
1351 		case 2:
1352 			vc->vc_intensity = 0;
1353 			break;
1354 		case 3:
1355 			vc->vc_italic = 1;
1356 			break;
1357 		case 4:
1358 			vc->vc_underline = 1;
1359 			break;
1360 		case 5:
1361 			vc->vc_blink = 1;
1362 			break;
1363 		case 7:
1364 			vc->vc_reverse = 1;
1365 			break;
1366 		case 10: /* ANSI X3.64-1979 (SCO-ish?)
1367 			  * Select primary font, don't display control chars if
1368 			  * defined, don't set bit 8 on output.
1369 			  */
1370 			vc->vc_translate = set_translate(vc->vc_charset == 0
1371 					? vc->vc_G0_charset
1372 					: vc->vc_G1_charset, vc);
1373 			vc->vc_disp_ctrl = 0;
1374 			vc->vc_toggle_meta = 0;
1375 			break;
1376 		case 11: /* ANSI X3.64-1979 (SCO-ish?)
1377 			  * Select first alternate font, lets chars < 32 be
1378 			  * displayed as ROM chars.
1379 			  */
1380 			vc->vc_translate = set_translate(IBMPC_MAP, vc);
1381 			vc->vc_disp_ctrl = 1;
1382 			vc->vc_toggle_meta = 0;
1383 			break;
1384 		case 12: /* ANSI X3.64-1979 (SCO-ish?)
1385 			  * Select second alternate font, toggle high bit
1386 			  * before displaying as ROM char.
1387 			  */
1388 			vc->vc_translate = set_translate(IBMPC_MAP, vc);
1389 			vc->vc_disp_ctrl = 1;
1390 			vc->vc_toggle_meta = 1;
1391 			break;
1392 		case 21:
1393 		case 22:
1394 			vc->vc_intensity = 1;
1395 			break;
1396 		case 23:
1397 			vc->vc_italic = 0;
1398 			break;
1399 		case 24:
1400 			vc->vc_underline = 0;
1401 			break;
1402 		case 25:
1403 			vc->vc_blink = 0;
1404 			break;
1405 		case 27:
1406 			vc->vc_reverse = 0;
1407 			break;
1408 		case 38:
1409 			i = vc_t416_color(vc, i, rgb_foreground);
1410 			break;
1411 		case 48:
1412 			i = vc_t416_color(vc, i, rgb_background);
1413 			break;
1414 		case 39:
1415 			vc->vc_color = (vc->vc_def_color & 0x0f) |
1416 				(vc->vc_color & 0xf0);
1417 			break;
1418 		case 49:
1419 			vc->vc_color = (vc->vc_def_color & 0xf0) |
1420 				(vc->vc_color & 0x0f);
1421 			break;
1422 		default:
1423 			if (vc->vc_par[i] >= 90 && vc->vc_par[i] <= 107) {
1424 				if (vc->vc_par[i] < 100)
1425 					vc->vc_intensity = 2;
1426 				vc->vc_par[i] -= 60;
1427 			}
1428 			if (vc->vc_par[i] >= 30 && vc->vc_par[i] <= 37)
1429 				vc->vc_color = color_table[vc->vc_par[i] - 30]
1430 					| (vc->vc_color & 0xf0);
1431 			else if (vc->vc_par[i] >= 40 && vc->vc_par[i] <= 47)
1432 				vc->vc_color = (color_table[vc->vc_par[i] - 40] << 4)
1433 					| (vc->vc_color & 0x0f);
1434 			break;
1435 		}
1436 	update_attr(vc);
1437 }
1438 
1439 static void respond_string(const char *p, struct tty_port *port)
1440 {
1441 	while (*p) {
1442 		tty_insert_flip_char(port, *p, 0);
1443 		p++;
1444 	}
1445 	tty_schedule_flip(port);
1446 }
1447 
1448 static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
1449 {
1450 	char buf[40];
1451 
1452 	sprintf(buf, "\033[%d;%dR", vc->vc_y + (vc->vc_decom ? vc->vc_top + 1 : 1), vc->vc_x + 1);
1453 	respond_string(buf, tty->port);
1454 }
1455 
1456 static inline void status_report(struct tty_struct *tty)
1457 {
1458 	respond_string("\033[0n", tty->port);	/* Terminal ok */
1459 }
1460 
1461 static inline void respond_ID(struct tty_struct *tty)
1462 {
1463 	respond_string(VT102ID, tty->port);
1464 }
1465 
1466 void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
1467 {
1468 	char buf[8];
1469 
1470 	sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt), (char)('!' + mrx),
1471 		(char)('!' + mry));
1472 	respond_string(buf, tty->port);
1473 }
1474 
1475 /* invoked via ioctl(TIOCLINUX) and through set_selection */
1476 int mouse_reporting(void)
1477 {
1478 	return vc_cons[fg_console].d->vc_report_mouse;
1479 }
1480 
1481 /* console_lock is held */
1482 static void set_mode(struct vc_data *vc, int on_off)
1483 {
1484 	int i;
1485 
1486 	for (i = 0; i <= vc->vc_npar; i++)
1487 		if (vc->vc_ques) {
1488 			switch(vc->vc_par[i]) {	/* DEC private modes set/reset */
1489 			case 1:			/* Cursor keys send ^[Ox/^[[x */
1490 				if (on_off)
1491 					set_kbd(vc, decckm);
1492 				else
1493 					clr_kbd(vc, decckm);
1494 				break;
1495 			case 3:	/* 80/132 mode switch unimplemented */
1496 #if 0
1497 				vc_resize(deccolm ? 132 : 80, vc->vc_rows);
1498 				/* this alone does not suffice; some user mode
1499 				   utility has to change the hardware regs */
1500 #endif
1501 				break;
1502 			case 5:			/* Inverted screen on/off */
1503 				if (vc->vc_decscnm != on_off) {
1504 					vc->vc_decscnm = on_off;
1505 					invert_screen(vc, 0, vc->vc_screenbuf_size, 0);
1506 					update_attr(vc);
1507 				}
1508 				break;
1509 			case 6:			/* Origin relative/absolute */
1510 				vc->vc_decom = on_off;
1511 				gotoxay(vc, 0, 0);
1512 				break;
1513 			case 7:			/* Autowrap on/off */
1514 				vc->vc_decawm = on_off;
1515 				break;
1516 			case 8:			/* Autorepeat on/off */
1517 				if (on_off)
1518 					set_kbd(vc, decarm);
1519 				else
1520 					clr_kbd(vc, decarm);
1521 				break;
1522 			case 9:
1523 				vc->vc_report_mouse = on_off ? 1 : 0;
1524 				break;
1525 			case 25:		/* Cursor on/off */
1526 				vc->vc_deccm = on_off;
1527 				break;
1528 			case 1000:
1529 				vc->vc_report_mouse = on_off ? 2 : 0;
1530 				break;
1531 			}
1532 		} else {
1533 			switch(vc->vc_par[i]) {	/* ANSI modes set/reset */
1534 			case 3:			/* Monitor (display ctrls) */
1535 				vc->vc_disp_ctrl = on_off;
1536 				break;
1537 			case 4:			/* Insert Mode on/off */
1538 				vc->vc_decim = on_off;
1539 				break;
1540 			case 20:		/* Lf, Enter == CrLf/Lf */
1541 				if (on_off)
1542 					set_kbd(vc, lnm);
1543 				else
1544 					clr_kbd(vc, lnm);
1545 				break;
1546 			}
1547 		}
1548 }
1549 
1550 /* console_lock is held */
1551 static void setterm_command(struct vc_data *vc)
1552 {
1553 	switch(vc->vc_par[0]) {
1554 		case 1:	/* set color for underline mode */
1555 			if (vc->vc_can_do_color &&
1556 					vc->vc_par[1] < 16) {
1557 				vc->vc_ulcolor = color_table[vc->vc_par[1]];
1558 				if (vc->vc_underline)
1559 					update_attr(vc);
1560 			}
1561 			break;
1562 		case 2:	/* set color for half intensity mode */
1563 			if (vc->vc_can_do_color &&
1564 					vc->vc_par[1] < 16) {
1565 				vc->vc_halfcolor = color_table[vc->vc_par[1]];
1566 				if (vc->vc_intensity == 0)
1567 					update_attr(vc);
1568 			}
1569 			break;
1570 		case 8:	/* store colors as defaults */
1571 			vc->vc_def_color = vc->vc_attr;
1572 			if (vc->vc_hi_font_mask == 0x100)
1573 				vc->vc_def_color >>= 1;
1574 			default_attr(vc);
1575 			update_attr(vc);
1576 			break;
1577 		case 9:	/* set blanking interval */
1578 			blankinterval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60;
1579 			poke_blanked_console();
1580 			break;
1581 		case 10: /* set bell frequency in Hz */
1582 			if (vc->vc_npar >= 1)
1583 				vc->vc_bell_pitch = vc->vc_par[1];
1584 			else
1585 				vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
1586 			break;
1587 		case 11: /* set bell duration in msec */
1588 			if (vc->vc_npar >= 1)
1589 				vc->vc_bell_duration = (vc->vc_par[1] < 2000) ?
1590 					msecs_to_jiffies(vc->vc_par[1]) : 0;
1591 			else
1592 				vc->vc_bell_duration = DEFAULT_BELL_DURATION;
1593 			break;
1594 		case 12: /* bring specified console to the front */
1595 			if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1))
1596 				set_console(vc->vc_par[1] - 1);
1597 			break;
1598 		case 13: /* unblank the screen */
1599 			poke_blanked_console();
1600 			break;
1601 		case 14: /* set vesa powerdown interval */
1602 			vesa_off_interval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60 * HZ;
1603 			break;
1604 		case 15: /* activate the previous console */
1605 			set_console(last_console);
1606 			break;
1607 		case 16: /* set cursor blink duration in msec */
1608 			if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 &&
1609 					vc->vc_par[1] <= USHRT_MAX)
1610 				vc->vc_cur_blink_ms = vc->vc_par[1];
1611 			else
1612 				vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1613 			break;
1614 	}
1615 }
1616 
1617 /* console_lock is held */
1618 static void csi_at(struct vc_data *vc, unsigned int nr)
1619 {
1620 	if (nr > vc->vc_cols - vc->vc_x)
1621 		nr = vc->vc_cols - vc->vc_x;
1622 	else if (!nr)
1623 		nr = 1;
1624 	insert_char(vc, nr);
1625 }
1626 
1627 /* console_lock is held */
1628 static void csi_L(struct vc_data *vc, unsigned int nr)
1629 {
1630 	if (nr > vc->vc_rows - vc->vc_y)
1631 		nr = vc->vc_rows - vc->vc_y;
1632 	else if (!nr)
1633 		nr = 1;
1634 	scrdown(vc, vc->vc_y, vc->vc_bottom, nr);
1635 	vc->vc_need_wrap = 0;
1636 }
1637 
1638 /* console_lock is held */
1639 static void csi_P(struct vc_data *vc, unsigned int nr)
1640 {
1641 	if (nr > vc->vc_cols - vc->vc_x)
1642 		nr = vc->vc_cols - vc->vc_x;
1643 	else if (!nr)
1644 		nr = 1;
1645 	delete_char(vc, nr);
1646 }
1647 
1648 /* console_lock is held */
1649 static void csi_M(struct vc_data *vc, unsigned int nr)
1650 {
1651 	if (nr > vc->vc_rows - vc->vc_y)
1652 		nr = vc->vc_rows - vc->vc_y;
1653 	else if (!nr)
1654 		nr=1;
1655 	scrup(vc, vc->vc_y, vc->vc_bottom, nr);
1656 	vc->vc_need_wrap = 0;
1657 }
1658 
1659 /* console_lock is held (except via vc_init->reset_terminal */
1660 static void save_cur(struct vc_data *vc)
1661 {
1662 	vc->vc_saved_x		= vc->vc_x;
1663 	vc->vc_saved_y		= vc->vc_y;
1664 	vc->vc_s_intensity	= vc->vc_intensity;
1665 	vc->vc_s_italic         = vc->vc_italic;
1666 	vc->vc_s_underline	= vc->vc_underline;
1667 	vc->vc_s_blink		= vc->vc_blink;
1668 	vc->vc_s_reverse	= vc->vc_reverse;
1669 	vc->vc_s_charset	= vc->vc_charset;
1670 	vc->vc_s_color		= vc->vc_color;
1671 	vc->vc_saved_G0		= vc->vc_G0_charset;
1672 	vc->vc_saved_G1		= vc->vc_G1_charset;
1673 }
1674 
1675 /* console_lock is held */
1676 static void restore_cur(struct vc_data *vc)
1677 {
1678 	gotoxy(vc, vc->vc_saved_x, vc->vc_saved_y);
1679 	vc->vc_intensity	= vc->vc_s_intensity;
1680 	vc->vc_italic		= vc->vc_s_italic;
1681 	vc->vc_underline	= vc->vc_s_underline;
1682 	vc->vc_blink		= vc->vc_s_blink;
1683 	vc->vc_reverse		= vc->vc_s_reverse;
1684 	vc->vc_charset		= vc->vc_s_charset;
1685 	vc->vc_color		= vc->vc_s_color;
1686 	vc->vc_G0_charset	= vc->vc_saved_G0;
1687 	vc->vc_G1_charset	= vc->vc_saved_G1;
1688 	vc->vc_translate	= set_translate(vc->vc_charset ? vc->vc_G1_charset : vc->vc_G0_charset, vc);
1689 	update_attr(vc);
1690 	vc->vc_need_wrap = 0;
1691 }
1692 
1693 enum { ESnormal, ESesc, ESsquare, ESgetpars, ESfunckey,
1694 	EShash, ESsetG0, ESsetG1, ESpercent, ESignore, ESnonstd,
1695 	ESpalette, ESosc };
1696 
1697 /* console_lock is held (except via vc_init()) */
1698 static void reset_terminal(struct vc_data *vc, int do_clear)
1699 {
1700 	vc->vc_top		= 0;
1701 	vc->vc_bottom		= vc->vc_rows;
1702 	vc->vc_state		= ESnormal;
1703 	vc->vc_ques		= 0;
1704 	vc->vc_translate	= set_translate(LAT1_MAP, vc);
1705 	vc->vc_G0_charset	= LAT1_MAP;
1706 	vc->vc_G1_charset	= GRAF_MAP;
1707 	vc->vc_charset		= 0;
1708 	vc->vc_need_wrap	= 0;
1709 	vc->vc_report_mouse	= 0;
1710 	vc->vc_utf              = default_utf8;
1711 	vc->vc_utf_count	= 0;
1712 
1713 	vc->vc_disp_ctrl	= 0;
1714 	vc->vc_toggle_meta	= 0;
1715 
1716 	vc->vc_decscnm		= 0;
1717 	vc->vc_decom		= 0;
1718 	vc->vc_decawm		= 1;
1719 	vc->vc_deccm		= global_cursor_default;
1720 	vc->vc_decim		= 0;
1721 
1722 	vt_reset_keyboard(vc->vc_num);
1723 
1724 	vc->vc_cursor_type = cur_default;
1725 	vc->vc_complement_mask = vc->vc_s_complement_mask;
1726 
1727 	default_attr(vc);
1728 	update_attr(vc);
1729 
1730 	vc->vc_tab_stop[0]	= 0x01010100;
1731 	vc->vc_tab_stop[1]	=
1732 	vc->vc_tab_stop[2]	=
1733 	vc->vc_tab_stop[3]	=
1734 	vc->vc_tab_stop[4]	=
1735 	vc->vc_tab_stop[5]	=
1736 	vc->vc_tab_stop[6]	=
1737 	vc->vc_tab_stop[7]	= 0x01010101;
1738 
1739 	vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
1740 	vc->vc_bell_duration = DEFAULT_BELL_DURATION;
1741 	vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1742 
1743 	gotoxy(vc, 0, 0);
1744 	save_cur(vc);
1745 	if (do_clear)
1746 	    csi_J(vc, 2);
1747 }
1748 
1749 /* console_lock is held */
1750 static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
1751 {
1752 	/*
1753 	 *  Control characters can be used in the _middle_
1754 	 *  of an escape sequence.
1755 	 */
1756 	if (vc->vc_state == ESosc && c>=8 && c<=13) /* ... except for OSC */
1757 		return;
1758 	switch (c) {
1759 	case 0:
1760 		return;
1761 	case 7:
1762 		if (vc->vc_state == ESosc)
1763 			vc->vc_state = ESnormal;
1764 		else if (vc->vc_bell_duration)
1765 			kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration);
1766 		return;
1767 	case 8:
1768 		bs(vc);
1769 		return;
1770 	case 9:
1771 		vc->vc_pos -= (vc->vc_x << 1);
1772 		while (vc->vc_x < vc->vc_cols - 1) {
1773 			vc->vc_x++;
1774 			if (vc->vc_tab_stop[vc->vc_x >> 5] & (1 << (vc->vc_x & 31)))
1775 				break;
1776 		}
1777 		vc->vc_pos += (vc->vc_x << 1);
1778 		notify_write(vc, '\t');
1779 		return;
1780 	case 10: case 11: case 12:
1781 		lf(vc);
1782 		if (!is_kbd(vc, lnm))
1783 			return;
1784 	case 13:
1785 		cr(vc);
1786 		return;
1787 	case 14:
1788 		vc->vc_charset = 1;
1789 		vc->vc_translate = set_translate(vc->vc_G1_charset, vc);
1790 		vc->vc_disp_ctrl = 1;
1791 		return;
1792 	case 15:
1793 		vc->vc_charset = 0;
1794 		vc->vc_translate = set_translate(vc->vc_G0_charset, vc);
1795 		vc->vc_disp_ctrl = 0;
1796 		return;
1797 	case 24: case 26:
1798 		vc->vc_state = ESnormal;
1799 		return;
1800 	case 27:
1801 		vc->vc_state = ESesc;
1802 		return;
1803 	case 127:
1804 		del(vc);
1805 		return;
1806 	case 128+27:
1807 		vc->vc_state = ESsquare;
1808 		return;
1809 	}
1810 	switch(vc->vc_state) {
1811 	case ESesc:
1812 		vc->vc_state = ESnormal;
1813 		switch (c) {
1814 		case '[':
1815 			vc->vc_state = ESsquare;
1816 			return;
1817 		case ']':
1818 			vc->vc_state = ESnonstd;
1819 			return;
1820 		case '%':
1821 			vc->vc_state = ESpercent;
1822 			return;
1823 		case 'E':
1824 			cr(vc);
1825 			lf(vc);
1826 			return;
1827 		case 'M':
1828 			ri(vc);
1829 			return;
1830 		case 'D':
1831 			lf(vc);
1832 			return;
1833 		case 'H':
1834 			vc->vc_tab_stop[vc->vc_x >> 5] |= (1 << (vc->vc_x & 31));
1835 			return;
1836 		case 'Z':
1837 			respond_ID(tty);
1838 			return;
1839 		case '7':
1840 			save_cur(vc);
1841 			return;
1842 		case '8':
1843 			restore_cur(vc);
1844 			return;
1845 		case '(':
1846 			vc->vc_state = ESsetG0;
1847 			return;
1848 		case ')':
1849 			vc->vc_state = ESsetG1;
1850 			return;
1851 		case '#':
1852 			vc->vc_state = EShash;
1853 			return;
1854 		case 'c':
1855 			reset_terminal(vc, 1);
1856 			return;
1857 		case '>':  /* Numeric keypad */
1858 			clr_kbd(vc, kbdapplic);
1859 			return;
1860 		case '=':  /* Appl. keypad */
1861 			set_kbd(vc, kbdapplic);
1862 			return;
1863 		}
1864 		return;
1865 	case ESnonstd:
1866 		if (c=='P') {   /* palette escape sequence */
1867 			for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
1868 				vc->vc_par[vc->vc_npar] = 0;
1869 			vc->vc_npar = 0;
1870 			vc->vc_state = ESpalette;
1871 			return;
1872 		} else if (c=='R') {   /* reset palette */
1873 			reset_palette(vc);
1874 			vc->vc_state = ESnormal;
1875 		} else if (c>='0' && c<='9')
1876 			vc->vc_state = ESosc;
1877 		else
1878 			vc->vc_state = ESnormal;
1879 		return;
1880 	case ESpalette:
1881 		if (isxdigit(c)) {
1882 			vc->vc_par[vc->vc_npar++] = hex_to_bin(c);
1883 			if (vc->vc_npar == 7) {
1884 				int i = vc->vc_par[0] * 3, j = 1;
1885 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
1886 				vc->vc_palette[i++] += vc->vc_par[j++];
1887 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
1888 				vc->vc_palette[i++] += vc->vc_par[j++];
1889 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
1890 				vc->vc_palette[i] += vc->vc_par[j];
1891 				set_palette(vc);
1892 				vc->vc_state = ESnormal;
1893 			}
1894 		} else
1895 			vc->vc_state = ESnormal;
1896 		return;
1897 	case ESsquare:
1898 		for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
1899 			vc->vc_par[vc->vc_npar] = 0;
1900 		vc->vc_npar = 0;
1901 		vc->vc_state = ESgetpars;
1902 		if (c == '[') { /* Function key */
1903 			vc->vc_state=ESfunckey;
1904 			return;
1905 		}
1906 		vc->vc_ques = (c == '?');
1907 		if (vc->vc_ques)
1908 			return;
1909 	case ESgetpars:
1910 		if (c == ';' && vc->vc_npar < NPAR - 1) {
1911 			vc->vc_npar++;
1912 			return;
1913 		} else if (c>='0' && c<='9') {
1914 			vc->vc_par[vc->vc_npar] *= 10;
1915 			vc->vc_par[vc->vc_npar] += c - '0';
1916 			return;
1917 		}
1918 		vc->vc_state = ESnormal;
1919 		switch(c) {
1920 		case 'h':
1921 			set_mode(vc, 1);
1922 			return;
1923 		case 'l':
1924 			set_mode(vc, 0);
1925 			return;
1926 		case 'c':
1927 			if (vc->vc_ques) {
1928 				if (vc->vc_par[0])
1929 					vc->vc_cursor_type = vc->vc_par[0] | (vc->vc_par[1] << 8) | (vc->vc_par[2] << 16);
1930 				else
1931 					vc->vc_cursor_type = cur_default;
1932 				return;
1933 			}
1934 			break;
1935 		case 'm':
1936 			if (vc->vc_ques) {
1937 				clear_selection();
1938 				if (vc->vc_par[0])
1939 					vc->vc_complement_mask = vc->vc_par[0] << 8 | vc->vc_par[1];
1940 				else
1941 					vc->vc_complement_mask = vc->vc_s_complement_mask;
1942 				return;
1943 			}
1944 			break;
1945 		case 'n':
1946 			if (!vc->vc_ques) {
1947 				if (vc->vc_par[0] == 5)
1948 					status_report(tty);
1949 				else if (vc->vc_par[0] == 6)
1950 					cursor_report(vc, tty);
1951 			}
1952 			return;
1953 		}
1954 		if (vc->vc_ques) {
1955 			vc->vc_ques = 0;
1956 			return;
1957 		}
1958 		switch(c) {
1959 		case 'G': case '`':
1960 			if (vc->vc_par[0])
1961 				vc->vc_par[0]--;
1962 			gotoxy(vc, vc->vc_par[0], vc->vc_y);
1963 			return;
1964 		case 'A':
1965 			if (!vc->vc_par[0])
1966 				vc->vc_par[0]++;
1967 			gotoxy(vc, vc->vc_x, vc->vc_y - vc->vc_par[0]);
1968 			return;
1969 		case 'B': case 'e':
1970 			if (!vc->vc_par[0])
1971 				vc->vc_par[0]++;
1972 			gotoxy(vc, vc->vc_x, vc->vc_y + vc->vc_par[0]);
1973 			return;
1974 		case 'C': case 'a':
1975 			if (!vc->vc_par[0])
1976 				vc->vc_par[0]++;
1977 			gotoxy(vc, vc->vc_x + vc->vc_par[0], vc->vc_y);
1978 			return;
1979 		case 'D':
1980 			if (!vc->vc_par[0])
1981 				vc->vc_par[0]++;
1982 			gotoxy(vc, vc->vc_x - vc->vc_par[0], vc->vc_y);
1983 			return;
1984 		case 'E':
1985 			if (!vc->vc_par[0])
1986 				vc->vc_par[0]++;
1987 			gotoxy(vc, 0, vc->vc_y + vc->vc_par[0]);
1988 			return;
1989 		case 'F':
1990 			if (!vc->vc_par[0])
1991 				vc->vc_par[0]++;
1992 			gotoxy(vc, 0, vc->vc_y - vc->vc_par[0]);
1993 			return;
1994 		case 'd':
1995 			if (vc->vc_par[0])
1996 				vc->vc_par[0]--;
1997 			gotoxay(vc, vc->vc_x ,vc->vc_par[0]);
1998 			return;
1999 		case 'H': case 'f':
2000 			if (vc->vc_par[0])
2001 				vc->vc_par[0]--;
2002 			if (vc->vc_par[1])
2003 				vc->vc_par[1]--;
2004 			gotoxay(vc, vc->vc_par[1], vc->vc_par[0]);
2005 			return;
2006 		case 'J':
2007 			csi_J(vc, vc->vc_par[0]);
2008 			return;
2009 		case 'K':
2010 			csi_K(vc, vc->vc_par[0]);
2011 			return;
2012 		case 'L':
2013 			csi_L(vc, vc->vc_par[0]);
2014 			return;
2015 		case 'M':
2016 			csi_M(vc, vc->vc_par[0]);
2017 			return;
2018 		case 'P':
2019 			csi_P(vc, vc->vc_par[0]);
2020 			return;
2021 		case 'c':
2022 			if (!vc->vc_par[0])
2023 				respond_ID(tty);
2024 			return;
2025 		case 'g':
2026 			if (!vc->vc_par[0])
2027 				vc->vc_tab_stop[vc->vc_x >> 5] &= ~(1 << (vc->vc_x & 31));
2028 			else if (vc->vc_par[0] == 3) {
2029 				vc->vc_tab_stop[0] =
2030 					vc->vc_tab_stop[1] =
2031 					vc->vc_tab_stop[2] =
2032 					vc->vc_tab_stop[3] =
2033 					vc->vc_tab_stop[4] =
2034 					vc->vc_tab_stop[5] =
2035 					vc->vc_tab_stop[6] =
2036 					vc->vc_tab_stop[7] = 0;
2037 			}
2038 			return;
2039 		case 'm':
2040 			csi_m(vc);
2041 			return;
2042 		case 'q': /* DECLL - but only 3 leds */
2043 			/* map 0,1,2,3 to 0,1,2,4 */
2044 			if (vc->vc_par[0] < 4)
2045 				vt_set_led_state(vc->vc_num,
2046 					    (vc->vc_par[0] < 3) ? vc->vc_par[0] : 4);
2047 			return;
2048 		case 'r':
2049 			if (!vc->vc_par[0])
2050 				vc->vc_par[0]++;
2051 			if (!vc->vc_par[1])
2052 				vc->vc_par[1] = vc->vc_rows;
2053 			/* Minimum allowed region is 2 lines */
2054 			if (vc->vc_par[0] < vc->vc_par[1] &&
2055 			    vc->vc_par[1] <= vc->vc_rows) {
2056 				vc->vc_top = vc->vc_par[0] - 1;
2057 				vc->vc_bottom = vc->vc_par[1];
2058 				gotoxay(vc, 0, 0);
2059 			}
2060 			return;
2061 		case 's':
2062 			save_cur(vc);
2063 			return;
2064 		case 'u':
2065 			restore_cur(vc);
2066 			return;
2067 		case 'X':
2068 			csi_X(vc, vc->vc_par[0]);
2069 			return;
2070 		case '@':
2071 			csi_at(vc, vc->vc_par[0]);
2072 			return;
2073 		case ']': /* setterm functions */
2074 			setterm_command(vc);
2075 			return;
2076 		}
2077 		return;
2078 	case ESpercent:
2079 		vc->vc_state = ESnormal;
2080 		switch (c) {
2081 		case '@':  /* defined in ISO 2022 */
2082 			vc->vc_utf = 0;
2083 			return;
2084 		case 'G':  /* prelim official escape code */
2085 		case '8':  /* retained for compatibility */
2086 			vc->vc_utf = 1;
2087 			return;
2088 		}
2089 		return;
2090 	case ESfunckey:
2091 		vc->vc_state = ESnormal;
2092 		return;
2093 	case EShash:
2094 		vc->vc_state = ESnormal;
2095 		if (c == '8') {
2096 			/* DEC screen alignment test. kludge :-) */
2097 			vc->vc_video_erase_char =
2098 				(vc->vc_video_erase_char & 0xff00) | 'E';
2099 			csi_J(vc, 2);
2100 			vc->vc_video_erase_char =
2101 				(vc->vc_video_erase_char & 0xff00) | ' ';
2102 			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
2103 		}
2104 		return;
2105 	case ESsetG0:
2106 		if (c == '0')
2107 			vc->vc_G0_charset = GRAF_MAP;
2108 		else if (c == 'B')
2109 			vc->vc_G0_charset = LAT1_MAP;
2110 		else if (c == 'U')
2111 			vc->vc_G0_charset = IBMPC_MAP;
2112 		else if (c == 'K')
2113 			vc->vc_G0_charset = USER_MAP;
2114 		if (vc->vc_charset == 0)
2115 			vc->vc_translate = set_translate(vc->vc_G0_charset, vc);
2116 		vc->vc_state = ESnormal;
2117 		return;
2118 	case ESsetG1:
2119 		if (c == '0')
2120 			vc->vc_G1_charset = GRAF_MAP;
2121 		else if (c == 'B')
2122 			vc->vc_G1_charset = LAT1_MAP;
2123 		else if (c == 'U')
2124 			vc->vc_G1_charset = IBMPC_MAP;
2125 		else if (c == 'K')
2126 			vc->vc_G1_charset = USER_MAP;
2127 		if (vc->vc_charset == 1)
2128 			vc->vc_translate = set_translate(vc->vc_G1_charset, vc);
2129 		vc->vc_state = ESnormal;
2130 		return;
2131 	case ESosc:
2132 		return;
2133 	default:
2134 		vc->vc_state = ESnormal;
2135 	}
2136 }
2137 
2138 /* is_double_width() is based on the wcwidth() implementation by
2139  * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
2140  * Latest version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
2141  */
2142 struct interval {
2143 	uint32_t first;
2144 	uint32_t last;
2145 };
2146 
2147 static int bisearch(uint32_t ucs, const struct interval *table, int max)
2148 {
2149 	int min = 0;
2150 	int mid;
2151 
2152 	if (ucs < table[0].first || ucs > table[max].last)
2153 		return 0;
2154 	while (max >= min) {
2155 		mid = (min + max) / 2;
2156 		if (ucs > table[mid].last)
2157 			min = mid + 1;
2158 		else if (ucs < table[mid].first)
2159 			max = mid - 1;
2160 		else
2161 			return 1;
2162 	}
2163 	return 0;
2164 }
2165 
2166 static int is_double_width(uint32_t ucs)
2167 {
2168 	static const struct interval double_width[] = {
2169 		{ 0x1100, 0x115F }, { 0x2329, 0x232A }, { 0x2E80, 0x303E },
2170 		{ 0x3040, 0xA4CF }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF },
2171 		{ 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 },
2172 		{ 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }
2173 	};
2174 	return bisearch(ucs, double_width, ARRAY_SIZE(double_width) - 1);
2175 }
2176 
2177 static void con_flush(struct vc_data *vc, unsigned long draw_from,
2178 		unsigned long draw_to, int *draw_x)
2179 {
2180 	if (*draw_x < 0)
2181 		return;
2182 
2183 	vc->vc_sw->con_putcs(vc, (u16 *)draw_from,
2184 			(u16 *)draw_to - (u16 *)draw_from, vc->vc_y, *draw_x);
2185 	*draw_x = -1;
2186 }
2187 
2188 /* acquires console_lock */
2189 static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int count)
2190 {
2191 	int c, tc, ok, n = 0, draw_x = -1;
2192 	unsigned int currcons;
2193 	unsigned long draw_from = 0, draw_to = 0;
2194 	struct vc_data *vc;
2195 	unsigned char vc_attr;
2196 	struct vt_notifier_param param;
2197 	uint8_t rescan;
2198 	uint8_t inverse;
2199 	uint8_t width;
2200 	u16 himask, charmask;
2201 
2202 	if (in_interrupt())
2203 		return count;
2204 
2205 	might_sleep();
2206 
2207 	console_lock();
2208 	vc = tty->driver_data;
2209 	if (vc == NULL) {
2210 		printk(KERN_ERR "vt: argh, driver_data is NULL !\n");
2211 		console_unlock();
2212 		return 0;
2213 	}
2214 
2215 	currcons = vc->vc_num;
2216 	if (!vc_cons_allocated(currcons)) {
2217 		/* could this happen? */
2218 		pr_warn_once("con_write: tty %d not allocated\n", currcons+1);
2219 		console_unlock();
2220 		return 0;
2221 	}
2222 
2223 	himask = vc->vc_hi_font_mask;
2224 	charmask = himask ? 0x1ff : 0xff;
2225 
2226 	/* undraw cursor first */
2227 	if (con_is_fg(vc))
2228 		hide_cursor(vc);
2229 
2230 	param.vc = vc;
2231 
2232 	while (!tty->stopped && count) {
2233 		int orig = *buf;
2234 		c = orig;
2235 		buf++;
2236 		n++;
2237 		count--;
2238 		rescan = 0;
2239 		inverse = 0;
2240 		width = 1;
2241 
2242 		/* Do no translation at all in control states */
2243 		if (vc->vc_state != ESnormal) {
2244 			tc = c;
2245 		} else if (vc->vc_utf && !vc->vc_disp_ctrl) {
2246 		    /* Combine UTF-8 into Unicode in vc_utf_char.
2247 		     * vc_utf_count is the number of continuation bytes still
2248 		     * expected to arrive.
2249 		     * vc_npar is the number of continuation bytes arrived so
2250 		     * far
2251 		     */
2252 rescan_last_byte:
2253 		    if ((c & 0xc0) == 0x80) {
2254 			/* Continuation byte received */
2255 			static const uint32_t utf8_length_changes[] = { 0x0000007f, 0x000007ff, 0x0000ffff, 0x001fffff, 0x03ffffff, 0x7fffffff };
2256 			if (vc->vc_utf_count) {
2257 			    vc->vc_utf_char = (vc->vc_utf_char << 6) | (c & 0x3f);
2258 			    vc->vc_npar++;
2259 			    if (--vc->vc_utf_count) {
2260 				/* Still need some bytes */
2261 				continue;
2262 			    }
2263 			    /* Got a whole character */
2264 			    c = vc->vc_utf_char;
2265 			    /* Reject overlong sequences */
2266 			    if (c <= utf8_length_changes[vc->vc_npar - 1] ||
2267 					c > utf8_length_changes[vc->vc_npar])
2268 				c = 0xfffd;
2269 			} else {
2270 			    /* Unexpected continuation byte */
2271 			    vc->vc_utf_count = 0;
2272 			    c = 0xfffd;
2273 			}
2274 		    } else {
2275 			/* Single ASCII byte or first byte of a sequence received */
2276 			if (vc->vc_utf_count) {
2277 			    /* Continuation byte expected */
2278 			    rescan = 1;
2279 			    vc->vc_utf_count = 0;
2280 			    c = 0xfffd;
2281 			} else if (c > 0x7f) {
2282 			    /* First byte of a multibyte sequence received */
2283 			    vc->vc_npar = 0;
2284 			    if ((c & 0xe0) == 0xc0) {
2285 				vc->vc_utf_count = 1;
2286 				vc->vc_utf_char = (c & 0x1f);
2287 			    } else if ((c & 0xf0) == 0xe0) {
2288 				vc->vc_utf_count = 2;
2289 				vc->vc_utf_char = (c & 0x0f);
2290 			    } else if ((c & 0xf8) == 0xf0) {
2291 				vc->vc_utf_count = 3;
2292 				vc->vc_utf_char = (c & 0x07);
2293 			    } else if ((c & 0xfc) == 0xf8) {
2294 				vc->vc_utf_count = 4;
2295 				vc->vc_utf_char = (c & 0x03);
2296 			    } else if ((c & 0xfe) == 0xfc) {
2297 				vc->vc_utf_count = 5;
2298 				vc->vc_utf_char = (c & 0x01);
2299 			    } else {
2300 				/* 254 and 255 are invalid */
2301 				c = 0xfffd;
2302 			    }
2303 			    if (vc->vc_utf_count) {
2304 				/* Still need some bytes */
2305 				continue;
2306 			    }
2307 			}
2308 			/* Nothing to do if an ASCII byte was received */
2309 		    }
2310 		    /* End of UTF-8 decoding. */
2311 		    /* c is the received character, or U+FFFD for invalid sequences. */
2312 		    /* Replace invalid Unicode code points with U+FFFD too */
2313 		    if ((c >= 0xd800 && c <= 0xdfff) || c == 0xfffe || c == 0xffff)
2314 			c = 0xfffd;
2315 		    tc = c;
2316 		} else {	/* no utf or alternate charset mode */
2317 		    tc = vc_translate(vc, c);
2318 		}
2319 
2320 		param.c = tc;
2321 		if (atomic_notifier_call_chain(&vt_notifier_list, VT_PREWRITE,
2322 					&param) == NOTIFY_STOP)
2323 			continue;
2324 
2325                 /* If the original code was a control character we
2326                  * only allow a glyph to be displayed if the code is
2327                  * not normally used (such as for cursor movement) or
2328                  * if the disp_ctrl mode has been explicitly enabled.
2329                  * Certain characters (as given by the CTRL_ALWAYS
2330                  * bitmap) are always displayed as control characters,
2331                  * as the console would be pretty useless without
2332                  * them; to display an arbitrary font position use the
2333                  * direct-to-font zone in UTF-8 mode.
2334                  */
2335                 ok = tc && (c >= 32 ||
2336 			    !(vc->vc_disp_ctrl ? (CTRL_ALWAYS >> c) & 1 :
2337 				  vc->vc_utf || ((CTRL_ACTION >> c) & 1)))
2338 			&& (c != 127 || vc->vc_disp_ctrl)
2339 			&& (c != 128+27);
2340 
2341 		if (vc->vc_state == ESnormal && ok) {
2342 			if (vc->vc_utf && !vc->vc_disp_ctrl) {
2343 				if (is_double_width(c))
2344 					width = 2;
2345 			}
2346 			/* Now try to find out how to display it */
2347 			tc = conv_uni_to_pc(vc, tc);
2348 			if (tc & ~charmask) {
2349 				if (tc == -1 || tc == -2) {
2350 				    continue; /* nothing to display */
2351 				}
2352 				/* Glyph not found */
2353 				if ((!(vc->vc_utf && !vc->vc_disp_ctrl) || c < 128) && !(c & ~charmask)) {
2354 				    /* In legacy mode use the glyph we get by a 1:1 mapping.
2355 				       This would make absolutely no sense with Unicode in mind,
2356 				       but do this for ASCII characters since a font may lack
2357 				       Unicode mapping info and we don't want to end up with
2358 				       having question marks only. */
2359 				    tc = c;
2360 				} else {
2361 				    /* Display U+FFFD. If it's not found, display an inverse question mark. */
2362 				    tc = conv_uni_to_pc(vc, 0xfffd);
2363 				    if (tc < 0) {
2364 					inverse = 1;
2365 					tc = conv_uni_to_pc(vc, '?');
2366 					if (tc < 0) tc = '?';
2367 				    }
2368 				}
2369 			}
2370 
2371 			if (!inverse) {
2372 				vc_attr = vc->vc_attr;
2373 			} else {
2374 				/* invert vc_attr */
2375 				if (!vc->vc_can_do_color) {
2376 					vc_attr = (vc->vc_attr) ^ 0x08;
2377 				} else if (vc->vc_hi_font_mask == 0x100) {
2378 					vc_attr = ((vc->vc_attr) & 0x11) | (((vc->vc_attr) & 0xe0) >> 4) | (((vc->vc_attr) & 0x0e) << 4);
2379 				} else {
2380 					vc_attr = ((vc->vc_attr) & 0x88) | (((vc->vc_attr) & 0x70) >> 4) | (((vc->vc_attr) & 0x07) << 4);
2381 				}
2382 				con_flush(vc, draw_from, draw_to, &draw_x);
2383 			}
2384 
2385 			while (1) {
2386 				if (vc->vc_need_wrap || vc->vc_decim)
2387 					con_flush(vc, draw_from, draw_to,
2388 							&draw_x);
2389 				if (vc->vc_need_wrap) {
2390 					cr(vc);
2391 					lf(vc);
2392 				}
2393 				if (vc->vc_decim)
2394 					insert_char(vc, 1);
2395 				scr_writew(himask ?
2396 					     ((vc_attr << 8) & ~himask) + ((tc & 0x100) ? himask : 0) + (tc & 0xff) :
2397 					     (vc_attr << 8) + tc,
2398 					   (u16 *) vc->vc_pos);
2399 				if (con_should_update(vc) && draw_x < 0) {
2400 					draw_x = vc->vc_x;
2401 					draw_from = vc->vc_pos;
2402 				}
2403 				if (vc->vc_x == vc->vc_cols - 1) {
2404 					vc->vc_need_wrap = vc->vc_decawm;
2405 					draw_to = vc->vc_pos + 2;
2406 				} else {
2407 					vc->vc_x++;
2408 					draw_to = (vc->vc_pos += 2);
2409 				}
2410 
2411 				if (!--width) break;
2412 
2413 				tc = conv_uni_to_pc(vc, ' '); /* A space is printed in the second column */
2414 				if (tc < 0) tc = ' ';
2415 			}
2416 			notify_write(vc, c);
2417 
2418 			if (inverse)
2419 				con_flush(vc, draw_from, draw_to, &draw_x);
2420 
2421 			if (rescan) {
2422 				rescan = 0;
2423 				inverse = 0;
2424 				width = 1;
2425 				c = orig;
2426 				goto rescan_last_byte;
2427 			}
2428 			continue;
2429 		}
2430 		con_flush(vc, draw_from, draw_to, &draw_x);
2431 		do_con_trol(tty, vc, orig);
2432 	}
2433 	con_flush(vc, draw_from, draw_to, &draw_x);
2434 	console_conditional_schedule();
2435 	console_unlock();
2436 	notify_update(vc);
2437 	return n;
2438 }
2439 
2440 /*
2441  * This is the console switching callback.
2442  *
2443  * Doing console switching in a process context allows
2444  * us to do the switches asynchronously (needed when we want
2445  * to switch due to a keyboard interrupt).  Synchronization
2446  * with other console code and prevention of re-entrancy is
2447  * ensured with console_lock.
2448  */
2449 static void console_callback(struct work_struct *ignored)
2450 {
2451 	console_lock();
2452 
2453 	if (want_console >= 0) {
2454 		if (want_console != fg_console &&
2455 		    vc_cons_allocated(want_console)) {
2456 			hide_cursor(vc_cons[fg_console].d);
2457 			change_console(vc_cons[want_console].d);
2458 			/* we only changed when the console had already
2459 			   been allocated - a new console is not created
2460 			   in an interrupt routine */
2461 		}
2462 		want_console = -1;
2463 	}
2464 	if (do_poke_blanked_console) { /* do not unblank for a LED change */
2465 		do_poke_blanked_console = 0;
2466 		poke_blanked_console();
2467 	}
2468 	if (scrollback_delta) {
2469 		struct vc_data *vc = vc_cons[fg_console].d;
2470 		clear_selection();
2471 		if (vc->vc_mode == KD_TEXT && vc->vc_sw->con_scrolldelta)
2472 			vc->vc_sw->con_scrolldelta(vc, scrollback_delta);
2473 		scrollback_delta = 0;
2474 	}
2475 	if (blank_timer_expired) {
2476 		do_blank_screen(0);
2477 		blank_timer_expired = 0;
2478 	}
2479 	notify_update(vc_cons[fg_console].d);
2480 
2481 	console_unlock();
2482 }
2483 
2484 int set_console(int nr)
2485 {
2486 	struct vc_data *vc = vc_cons[fg_console].d;
2487 
2488 	if (!vc_cons_allocated(nr) || vt_dont_switch ||
2489 		(vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) {
2490 
2491 		/*
2492 		 * Console switch will fail in console_callback() or
2493 		 * change_console() so there is no point scheduling
2494 		 * the callback
2495 		 *
2496 		 * Existing set_console() users don't check the return
2497 		 * value so this shouldn't break anything
2498 		 */
2499 		return -EINVAL;
2500 	}
2501 
2502 	want_console = nr;
2503 	schedule_console_callback();
2504 
2505 	return 0;
2506 }
2507 
2508 struct tty_driver *console_driver;
2509 
2510 #ifdef CONFIG_VT_CONSOLE
2511 
2512 /**
2513  * vt_kmsg_redirect() - Sets/gets the kernel message console
2514  * @new:	The new virtual terminal number or -1 if the console should stay
2515  * 		unchanged
2516  *
2517  * By default, the kernel messages are always printed on the current virtual
2518  * console. However, the user may modify that default with the
2519  * TIOCL_SETKMSGREDIRECT ioctl call.
2520  *
2521  * This function sets the kernel message console to be @new. It returns the old
2522  * virtual console number. The virtual terminal number 0 (both as parameter and
2523  * return value) means no redirection (i.e. always printed on the currently
2524  * active console).
2525  *
2526  * The parameter -1 means that only the current console is returned, but the
2527  * value is not modified. You may use the macro vt_get_kmsg_redirect() in that
2528  * case to make the code more understandable.
2529  *
2530  * When the kernel is compiled without CONFIG_VT_CONSOLE, this function ignores
2531  * the parameter and always returns 0.
2532  */
2533 int vt_kmsg_redirect(int new)
2534 {
2535 	static int kmsg_con;
2536 
2537 	if (new != -1)
2538 		return xchg(&kmsg_con, new);
2539 	else
2540 		return kmsg_con;
2541 }
2542 
2543 /*
2544  *	Console on virtual terminal
2545  *
2546  * The console must be locked when we get here.
2547  */
2548 
2549 static void vt_console_print(struct console *co, const char *b, unsigned count)
2550 {
2551 	struct vc_data *vc = vc_cons[fg_console].d;
2552 	unsigned char c;
2553 	static DEFINE_SPINLOCK(printing_lock);
2554 	const ushort *start;
2555 	ushort cnt = 0;
2556 	ushort myx;
2557 	int kmsg_console;
2558 
2559 	/* console busy or not yet initialized */
2560 	if (!printable)
2561 		return;
2562 	if (!spin_trylock(&printing_lock))
2563 		return;
2564 
2565 	kmsg_console = vt_get_kmsg_redirect();
2566 	if (kmsg_console && vc_cons_allocated(kmsg_console - 1))
2567 		vc = vc_cons[kmsg_console - 1].d;
2568 
2569 	/* read `x' only after setting currcons properly (otherwise
2570 	   the `x' macro will read the x of the foreground console). */
2571 	myx = vc->vc_x;
2572 
2573 	if (!vc_cons_allocated(fg_console)) {
2574 		/* impossible */
2575 		/* printk("vt_console_print: tty %d not allocated ??\n", currcons+1); */
2576 		goto quit;
2577 	}
2578 
2579 	if (vc->vc_mode != KD_TEXT && !vt_force_oops_output(vc))
2580 		goto quit;
2581 
2582 	/* undraw cursor first */
2583 	if (con_is_fg(vc))
2584 		hide_cursor(vc);
2585 
2586 	start = (ushort *)vc->vc_pos;
2587 
2588 	/* Contrived structure to try to emulate original need_wrap behaviour
2589 	 * Problems caused when we have need_wrap set on '\n' character */
2590 	while (count--) {
2591 		c = *b++;
2592 		if (c == 10 || c == 13 || c == 8 || vc->vc_need_wrap) {
2593 			if (cnt > 0) {
2594 				if (con_is_visible(vc))
2595 					vc->vc_sw->con_putcs(vc, start, cnt, vc->vc_y, vc->vc_x);
2596 				vc->vc_x += cnt;
2597 				if (vc->vc_need_wrap)
2598 					vc->vc_x--;
2599 				cnt = 0;
2600 			}
2601 			if (c == 8) {		/* backspace */
2602 				bs(vc);
2603 				start = (ushort *)vc->vc_pos;
2604 				myx = vc->vc_x;
2605 				continue;
2606 			}
2607 			if (c != 13)
2608 				lf(vc);
2609 			cr(vc);
2610 			start = (ushort *)vc->vc_pos;
2611 			myx = vc->vc_x;
2612 			if (c == 10 || c == 13)
2613 				continue;
2614 		}
2615 		scr_writew((vc->vc_attr << 8) + c, (unsigned short *)vc->vc_pos);
2616 		notify_write(vc, c);
2617 		cnt++;
2618 		if (myx == vc->vc_cols - 1) {
2619 			vc->vc_need_wrap = 1;
2620 			continue;
2621 		}
2622 		vc->vc_pos += 2;
2623 		myx++;
2624 	}
2625 	if (cnt > 0) {
2626 		if (con_is_visible(vc))
2627 			vc->vc_sw->con_putcs(vc, start, cnt, vc->vc_y, vc->vc_x);
2628 		vc->vc_x += cnt;
2629 		if (vc->vc_x == vc->vc_cols) {
2630 			vc->vc_x--;
2631 			vc->vc_need_wrap = 1;
2632 		}
2633 	}
2634 	set_cursor(vc);
2635 	notify_update(vc);
2636 
2637 quit:
2638 	spin_unlock(&printing_lock);
2639 }
2640 
2641 static struct tty_driver *vt_console_device(struct console *c, int *index)
2642 {
2643 	*index = c->index ? c->index-1 : fg_console;
2644 	return console_driver;
2645 }
2646 
2647 static struct console vt_console_driver = {
2648 	.name		= "tty",
2649 	.write		= vt_console_print,
2650 	.device		= vt_console_device,
2651 	.unblank	= unblank_screen,
2652 	.flags		= CON_PRINTBUFFER,
2653 	.index		= -1,
2654 };
2655 #endif
2656 
2657 /*
2658  *	Handling of Linux-specific VC ioctls
2659  */
2660 
2661 /*
2662  * Generally a bit racy with respect to console_lock();.
2663  *
2664  * There are some functions which don't need it.
2665  *
2666  * There are some functions which can sleep for arbitrary periods
2667  * (paste_selection) but we don't need the lock there anyway.
2668  *
2669  * set_selection has locking, and definitely needs it
2670  */
2671 
2672 int tioclinux(struct tty_struct *tty, unsigned long arg)
2673 {
2674 	char type, data;
2675 	char __user *p = (char __user *)arg;
2676 	int lines;
2677 	int ret;
2678 
2679 	if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
2680 		return -EPERM;
2681 	if (get_user(type, p))
2682 		return -EFAULT;
2683 	ret = 0;
2684 
2685 	switch (type)
2686 	{
2687 		case TIOCL_SETSEL:
2688 			console_lock();
2689 			ret = set_selection((struct tiocl_selection __user *)(p+1), tty);
2690 			console_unlock();
2691 			break;
2692 		case TIOCL_PASTESEL:
2693 			ret = paste_selection(tty);
2694 			break;
2695 		case TIOCL_UNBLANKSCREEN:
2696 			console_lock();
2697 			unblank_screen();
2698 			console_unlock();
2699 			break;
2700 		case TIOCL_SELLOADLUT:
2701 			console_lock();
2702 			ret = sel_loadlut(p);
2703 			console_unlock();
2704 			break;
2705 		case TIOCL_GETSHIFTSTATE:
2706 
2707 	/*
2708 	 * Make it possible to react to Shift+Mousebutton.
2709 	 * Note that 'shift_state' is an undocumented
2710 	 * kernel-internal variable; programs not closely
2711 	 * related to the kernel should not use this.
2712 	 */
2713 			data = vt_get_shift_state();
2714 			ret = __put_user(data, p);
2715 			break;
2716 		case TIOCL_GETMOUSEREPORTING:
2717 			console_lock();	/* May be overkill */
2718 			data = mouse_reporting();
2719 			console_unlock();
2720 			ret = __put_user(data, p);
2721 			break;
2722 		case TIOCL_SETVESABLANK:
2723 			console_lock();
2724 			ret = set_vesa_blanking(p);
2725 			console_unlock();
2726 			break;
2727 		case TIOCL_GETKMSGREDIRECT:
2728 			data = vt_get_kmsg_redirect();
2729 			ret = __put_user(data, p);
2730 			break;
2731 		case TIOCL_SETKMSGREDIRECT:
2732 			if (!capable(CAP_SYS_ADMIN)) {
2733 				ret = -EPERM;
2734 			} else {
2735 				if (get_user(data, p+1))
2736 					ret = -EFAULT;
2737 				else
2738 					vt_kmsg_redirect(data);
2739 			}
2740 			break;
2741 		case TIOCL_GETFGCONSOLE:
2742 			/* No locking needed as this is a transiently
2743 			   correct return anyway if the caller hasn't
2744 			   disabled switching */
2745 			ret = fg_console;
2746 			break;
2747 		case TIOCL_SCROLLCONSOLE:
2748 			if (get_user(lines, (s32 __user *)(p+4))) {
2749 				ret = -EFAULT;
2750 			} else {
2751 				/* Need the console lock here. Note that lots
2752 				   of other calls need fixing before the lock
2753 				   is actually useful ! */
2754 				console_lock();
2755 				scrollfront(vc_cons[fg_console].d, lines);
2756 				console_unlock();
2757 				ret = 0;
2758 			}
2759 			break;
2760 		case TIOCL_BLANKSCREEN:	/* until explicitly unblanked, not only poked */
2761 			console_lock();
2762 			ignore_poke = 1;
2763 			do_blank_screen(0);
2764 			console_unlock();
2765 			break;
2766 		case TIOCL_BLANKEDSCREEN:
2767 			ret = console_blanked;
2768 			break;
2769 		default:
2770 			ret = -EINVAL;
2771 			break;
2772 	}
2773 	return ret;
2774 }
2775 
2776 /*
2777  * /dev/ttyN handling
2778  */
2779 
2780 static int con_write(struct tty_struct *tty, const unsigned char *buf, int count)
2781 {
2782 	int	retval;
2783 
2784 	retval = do_con_write(tty, buf, count);
2785 	con_flush_chars(tty);
2786 
2787 	return retval;
2788 }
2789 
2790 static int con_put_char(struct tty_struct *tty, unsigned char ch)
2791 {
2792 	if (in_interrupt())
2793 		return 0;	/* n_r3964 calls put_char() from interrupt context */
2794 	return do_con_write(tty, &ch, 1);
2795 }
2796 
2797 static int con_write_room(struct tty_struct *tty)
2798 {
2799 	if (tty->stopped)
2800 		return 0;
2801 	return 32768;		/* No limit, really; we're not buffering */
2802 }
2803 
2804 static int con_chars_in_buffer(struct tty_struct *tty)
2805 {
2806 	return 0;		/* we're not buffering */
2807 }
2808 
2809 /*
2810  * con_throttle and con_unthrottle are only used for
2811  * paste_selection(), which has to stuff in a large number of
2812  * characters...
2813  */
2814 static void con_throttle(struct tty_struct *tty)
2815 {
2816 }
2817 
2818 static void con_unthrottle(struct tty_struct *tty)
2819 {
2820 	struct vc_data *vc = tty->driver_data;
2821 
2822 	wake_up_interruptible(&vc->paste_wait);
2823 }
2824 
2825 /*
2826  * Turn the Scroll-Lock LED on when the tty is stopped
2827  */
2828 static void con_stop(struct tty_struct *tty)
2829 {
2830 	int console_num;
2831 	if (!tty)
2832 		return;
2833 	console_num = tty->index;
2834 	if (!vc_cons_allocated(console_num))
2835 		return;
2836 	vt_kbd_con_stop(console_num);
2837 }
2838 
2839 /*
2840  * Turn the Scroll-Lock LED off when the console is started
2841  */
2842 static void con_start(struct tty_struct *tty)
2843 {
2844 	int console_num;
2845 	if (!tty)
2846 		return;
2847 	console_num = tty->index;
2848 	if (!vc_cons_allocated(console_num))
2849 		return;
2850 	vt_kbd_con_start(console_num);
2851 }
2852 
2853 static void con_flush_chars(struct tty_struct *tty)
2854 {
2855 	struct vc_data *vc;
2856 
2857 	if (in_interrupt())	/* from flush_to_ldisc */
2858 		return;
2859 
2860 	/* if we race with con_close(), vt may be null */
2861 	console_lock();
2862 	vc = tty->driver_data;
2863 	if (vc)
2864 		set_cursor(vc);
2865 	console_unlock();
2866 }
2867 
2868 /*
2869  * Allocate the console screen memory.
2870  */
2871 static int con_install(struct tty_driver *driver, struct tty_struct *tty)
2872 {
2873 	unsigned int currcons = tty->index;
2874 	struct vc_data *vc;
2875 	int ret;
2876 
2877 	console_lock();
2878 	ret = vc_allocate(currcons);
2879 	if (ret)
2880 		goto unlock;
2881 
2882 	vc = vc_cons[currcons].d;
2883 
2884 	/* Still being freed */
2885 	if (vc->port.tty) {
2886 		ret = -ERESTARTSYS;
2887 		goto unlock;
2888 	}
2889 
2890 	ret = tty_port_install(&vc->port, driver, tty);
2891 	if (ret)
2892 		goto unlock;
2893 
2894 	tty->driver_data = vc;
2895 	vc->port.tty = tty;
2896 
2897 	if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
2898 		tty->winsize.ws_row = vc_cons[currcons].d->vc_rows;
2899 		tty->winsize.ws_col = vc_cons[currcons].d->vc_cols;
2900 	}
2901 	if (vc->vc_utf)
2902 		tty->termios.c_iflag |= IUTF8;
2903 	else
2904 		tty->termios.c_iflag &= ~IUTF8;
2905 unlock:
2906 	console_unlock();
2907 	return ret;
2908 }
2909 
2910 static int con_open(struct tty_struct *tty, struct file *filp)
2911 {
2912 	/* everything done in install */
2913 	return 0;
2914 }
2915 
2916 
2917 static void con_close(struct tty_struct *tty, struct file *filp)
2918 {
2919 	/* Nothing to do - we defer to shutdown */
2920 }
2921 
2922 static void con_shutdown(struct tty_struct *tty)
2923 {
2924 	struct vc_data *vc = tty->driver_data;
2925 	BUG_ON(vc == NULL);
2926 	console_lock();
2927 	vc->port.tty = NULL;
2928 	console_unlock();
2929 }
2930 
2931 static int default_color           = 7; /* white */
2932 static int default_italic_color    = 2; // green (ASCII)
2933 static int default_underline_color = 3; // cyan (ASCII)
2934 module_param_named(color, default_color, int, S_IRUGO | S_IWUSR);
2935 module_param_named(italic, default_italic_color, int, S_IRUGO | S_IWUSR);
2936 module_param_named(underline, default_underline_color, int, S_IRUGO | S_IWUSR);
2937 
2938 static void vc_init(struct vc_data *vc, unsigned int rows,
2939 		    unsigned int cols, int do_clear)
2940 {
2941 	int j, k ;
2942 
2943 	vc->vc_cols = cols;
2944 	vc->vc_rows = rows;
2945 	vc->vc_size_row = cols << 1;
2946 	vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
2947 
2948 	set_origin(vc);
2949 	vc->vc_pos = vc->vc_origin;
2950 	reset_vc(vc);
2951 	for (j=k=0; j<16; j++) {
2952 		vc->vc_palette[k++] = default_red[j] ;
2953 		vc->vc_palette[k++] = default_grn[j] ;
2954 		vc->vc_palette[k++] = default_blu[j] ;
2955 	}
2956 	vc->vc_def_color       = default_color;
2957 	vc->vc_ulcolor         = default_underline_color;
2958 	vc->vc_itcolor         = default_italic_color;
2959 	vc->vc_halfcolor       = 0x08;   /* grey */
2960 	init_waitqueue_head(&vc->paste_wait);
2961 	reset_terminal(vc, do_clear);
2962 }
2963 
2964 /*
2965  * This routine initializes console interrupts, and does nothing
2966  * else. If you want the screen to clear, call tty_write with
2967  * the appropriate escape-sequence.
2968  */
2969 
2970 static int __init con_init(void)
2971 {
2972 	const char *display_desc = NULL;
2973 	struct vc_data *vc;
2974 	unsigned int currcons = 0, i;
2975 
2976 	console_lock();
2977 
2978 	if (conswitchp)
2979 		display_desc = conswitchp->con_startup();
2980 	if (!display_desc) {
2981 		fg_console = 0;
2982 		console_unlock();
2983 		return 0;
2984 	}
2985 
2986 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
2987 		struct con_driver *con_driver = &registered_con_driver[i];
2988 
2989 		if (con_driver->con == NULL) {
2990 			con_driver->con = conswitchp;
2991 			con_driver->desc = display_desc;
2992 			con_driver->flag = CON_DRIVER_FLAG_INIT;
2993 			con_driver->first = 0;
2994 			con_driver->last = MAX_NR_CONSOLES - 1;
2995 			break;
2996 		}
2997 	}
2998 
2999 	for (i = 0; i < MAX_NR_CONSOLES; i++)
3000 		con_driver_map[i] = conswitchp;
3001 
3002 	if (blankinterval) {
3003 		blank_state = blank_normal_wait;
3004 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3005 	}
3006 
3007 	for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) {
3008 		vc_cons[currcons].d = vc = kzalloc(sizeof(struct vc_data), GFP_NOWAIT);
3009 		INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
3010 		tty_port_init(&vc->port);
3011 		visual_init(vc, currcons, 1);
3012 		vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_NOWAIT);
3013 		vc_init(vc, vc->vc_rows, vc->vc_cols,
3014 			currcons || !vc->vc_sw->con_save_screen);
3015 	}
3016 	currcons = fg_console = 0;
3017 	master_display_fg = vc = vc_cons[currcons].d;
3018 	set_origin(vc);
3019 	save_screen(vc);
3020 	gotoxy(vc, vc->vc_x, vc->vc_y);
3021 	csi_J(vc, 0);
3022 	update_screen(vc);
3023 	pr_info("Console: %s %s %dx%d\n",
3024 		vc->vc_can_do_color ? "colour" : "mono",
3025 		display_desc, vc->vc_cols, vc->vc_rows);
3026 	printable = 1;
3027 
3028 	console_unlock();
3029 
3030 #ifdef CONFIG_VT_CONSOLE
3031 	register_console(&vt_console_driver);
3032 #endif
3033 	return 0;
3034 }
3035 console_initcall(con_init);
3036 
3037 static const struct tty_operations con_ops = {
3038 	.install = con_install,
3039 	.open = con_open,
3040 	.close = con_close,
3041 	.write = con_write,
3042 	.write_room = con_write_room,
3043 	.put_char = con_put_char,
3044 	.flush_chars = con_flush_chars,
3045 	.chars_in_buffer = con_chars_in_buffer,
3046 	.ioctl = vt_ioctl,
3047 #ifdef CONFIG_COMPAT
3048 	.compat_ioctl = vt_compat_ioctl,
3049 #endif
3050 	.stop = con_stop,
3051 	.start = con_start,
3052 	.throttle = con_throttle,
3053 	.unthrottle = con_unthrottle,
3054 	.resize = vt_resize,
3055 	.shutdown = con_shutdown
3056 };
3057 
3058 static struct cdev vc0_cdev;
3059 
3060 static ssize_t show_tty_active(struct device *dev,
3061 				struct device_attribute *attr, char *buf)
3062 {
3063 	return sprintf(buf, "tty%d\n", fg_console + 1);
3064 }
3065 static DEVICE_ATTR(active, S_IRUGO, show_tty_active, NULL);
3066 
3067 static struct attribute *vt_dev_attrs[] = {
3068 	&dev_attr_active.attr,
3069 	NULL
3070 };
3071 
3072 ATTRIBUTE_GROUPS(vt_dev);
3073 
3074 int __init vty_init(const struct file_operations *console_fops)
3075 {
3076 	cdev_init(&vc0_cdev, console_fops);
3077 	if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
3078 	    register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
3079 		panic("Couldn't register /dev/tty0 driver\n");
3080 	tty0dev = device_create_with_groups(tty_class, NULL,
3081 					    MKDEV(TTY_MAJOR, 0), NULL,
3082 					    vt_dev_groups, "tty0");
3083 	if (IS_ERR(tty0dev))
3084 		tty0dev = NULL;
3085 
3086 	vcs_init();
3087 
3088 	console_driver = alloc_tty_driver(MAX_NR_CONSOLES);
3089 	if (!console_driver)
3090 		panic("Couldn't allocate console driver\n");
3091 
3092 	console_driver->name = "tty";
3093 	console_driver->name_base = 1;
3094 	console_driver->major = TTY_MAJOR;
3095 	console_driver->minor_start = 1;
3096 	console_driver->type = TTY_DRIVER_TYPE_CONSOLE;
3097 	console_driver->init_termios = tty_std_termios;
3098 	if (default_utf8)
3099 		console_driver->init_termios.c_iflag |= IUTF8;
3100 	console_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS;
3101 	tty_set_operations(console_driver, &con_ops);
3102 	if (tty_register_driver(console_driver))
3103 		panic("Couldn't register console driver\n");
3104 	kbd_init();
3105 	console_map_init();
3106 #ifdef CONFIG_MDA_CONSOLE
3107 	mda_console_init();
3108 #endif
3109 	return 0;
3110 }
3111 
3112 #ifndef VT_SINGLE_DRIVER
3113 
3114 static struct class *vtconsole_class;
3115 
3116 static int do_bind_con_driver(const struct consw *csw, int first, int last,
3117 			   int deflt)
3118 {
3119 	struct module *owner = csw->owner;
3120 	const char *desc = NULL;
3121 	struct con_driver *con_driver;
3122 	int i, j = -1, k = -1, retval = -ENODEV;
3123 
3124 	if (!try_module_get(owner))
3125 		return -ENODEV;
3126 
3127 	WARN_CONSOLE_UNLOCKED();
3128 
3129 	/* check if driver is registered */
3130 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3131 		con_driver = &registered_con_driver[i];
3132 
3133 		if (con_driver->con == csw) {
3134 			desc = con_driver->desc;
3135 			retval = 0;
3136 			break;
3137 		}
3138 	}
3139 
3140 	if (retval)
3141 		goto err;
3142 
3143 	if (!(con_driver->flag & CON_DRIVER_FLAG_INIT)) {
3144 		csw->con_startup();
3145 		con_driver->flag |= CON_DRIVER_FLAG_INIT;
3146 	}
3147 
3148 	if (deflt) {
3149 		if (conswitchp)
3150 			module_put(conswitchp->owner);
3151 
3152 		__module_get(owner);
3153 		conswitchp = csw;
3154 	}
3155 
3156 	first = max(first, con_driver->first);
3157 	last = min(last, con_driver->last);
3158 
3159 	for (i = first; i <= last; i++) {
3160 		int old_was_color;
3161 		struct vc_data *vc = vc_cons[i].d;
3162 
3163 		if (con_driver_map[i])
3164 			module_put(con_driver_map[i]->owner);
3165 		__module_get(owner);
3166 		con_driver_map[i] = csw;
3167 
3168 		if (!vc || !vc->vc_sw)
3169 			continue;
3170 
3171 		j = i;
3172 
3173 		if (con_is_visible(vc)) {
3174 			k = i;
3175 			save_screen(vc);
3176 		}
3177 
3178 		old_was_color = vc->vc_can_do_color;
3179 		vc->vc_sw->con_deinit(vc);
3180 		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
3181 		visual_init(vc, i, 0);
3182 		set_origin(vc);
3183 		update_attr(vc);
3184 
3185 		/* If the console changed between mono <-> color, then
3186 		 * the attributes in the screenbuf will be wrong.  The
3187 		 * following resets all attributes to something sane.
3188 		 */
3189 		if (old_was_color != vc->vc_can_do_color)
3190 			clear_buffer_attributes(vc);
3191 	}
3192 
3193 	pr_info("Console: switching ");
3194 	if (!deflt)
3195 		printk(KERN_CONT "consoles %d-%d ", first+1, last+1);
3196 	if (j >= 0) {
3197 		struct vc_data *vc = vc_cons[j].d;
3198 
3199 		printk(KERN_CONT "to %s %s %dx%d\n",
3200 		       vc->vc_can_do_color ? "colour" : "mono",
3201 		       desc, vc->vc_cols, vc->vc_rows);
3202 
3203 		if (k >= 0) {
3204 			vc = vc_cons[k].d;
3205 			update_screen(vc);
3206 		}
3207 	} else
3208 		printk(KERN_CONT "to %s\n", desc);
3209 
3210 	retval = 0;
3211 err:
3212 	module_put(owner);
3213 	return retval;
3214 };
3215 
3216 
3217 #ifdef CONFIG_VT_HW_CONSOLE_BINDING
3218 /* unlocked version of unbind_con_driver() */
3219 int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
3220 {
3221 	struct module *owner = csw->owner;
3222 	const struct consw *defcsw = NULL;
3223 	struct con_driver *con_driver = NULL, *con_back = NULL;
3224 	int i, retval = -ENODEV;
3225 
3226 	if (!try_module_get(owner))
3227 		return -ENODEV;
3228 
3229 	WARN_CONSOLE_UNLOCKED();
3230 
3231 	/* check if driver is registered and if it is unbindable */
3232 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3233 		con_driver = &registered_con_driver[i];
3234 
3235 		if (con_driver->con == csw &&
3236 		    con_driver->flag & CON_DRIVER_FLAG_MODULE) {
3237 			retval = 0;
3238 			break;
3239 		}
3240 	}
3241 
3242 	if (retval)
3243 		goto err;
3244 
3245 	retval = -ENODEV;
3246 
3247 	/* check if backup driver exists */
3248 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3249 		con_back = &registered_con_driver[i];
3250 
3251 		if (con_back->con && con_back->con != csw) {
3252 			defcsw = con_back->con;
3253 			retval = 0;
3254 			break;
3255 		}
3256 	}
3257 
3258 	if (retval)
3259 		goto err;
3260 
3261 	if (!con_is_bound(csw))
3262 		goto err;
3263 
3264 	first = max(first, con_driver->first);
3265 	last = min(last, con_driver->last);
3266 
3267 	for (i = first; i <= last; i++) {
3268 		if (con_driver_map[i] == csw) {
3269 			module_put(csw->owner);
3270 			con_driver_map[i] = NULL;
3271 		}
3272 	}
3273 
3274 	if (!con_is_bound(defcsw)) {
3275 		const struct consw *defconsw = conswitchp;
3276 
3277 		defcsw->con_startup();
3278 		con_back->flag |= CON_DRIVER_FLAG_INIT;
3279 		/*
3280 		 * vgacon may change the default driver to point
3281 		 * to dummycon, we restore it here...
3282 		 */
3283 		conswitchp = defconsw;
3284 	}
3285 
3286 	if (!con_is_bound(csw))
3287 		con_driver->flag &= ~CON_DRIVER_FLAG_INIT;
3288 
3289 	/* ignore return value, binding should not fail */
3290 	do_bind_con_driver(defcsw, first, last, deflt);
3291 err:
3292 	module_put(owner);
3293 	return retval;
3294 
3295 }
3296 EXPORT_SYMBOL_GPL(do_unbind_con_driver);
3297 
3298 static int vt_bind(struct con_driver *con)
3299 {
3300 	const struct consw *defcsw = NULL, *csw = NULL;
3301 	int i, more = 1, first = -1, last = -1, deflt = 0;
3302 
3303  	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3304 		goto err;
3305 
3306 	csw = con->con;
3307 
3308 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3309 		struct con_driver *con = &registered_con_driver[i];
3310 
3311 		if (con->con && !(con->flag & CON_DRIVER_FLAG_MODULE)) {
3312 			defcsw = con->con;
3313 			break;
3314 		}
3315 	}
3316 
3317 	if (!defcsw)
3318 		goto err;
3319 
3320 	while (more) {
3321 		more = 0;
3322 
3323 		for (i = con->first; i <= con->last; i++) {
3324 			if (con_driver_map[i] == defcsw) {
3325 				if (first == -1)
3326 					first = i;
3327 				last = i;
3328 				more = 1;
3329 			} else if (first != -1)
3330 				break;
3331 		}
3332 
3333 		if (first == 0 && last == MAX_NR_CONSOLES -1)
3334 			deflt = 1;
3335 
3336 		if (first != -1)
3337 			do_bind_con_driver(csw, first, last, deflt);
3338 
3339 		first = -1;
3340 		last = -1;
3341 		deflt = 0;
3342 	}
3343 
3344 err:
3345 	return 0;
3346 }
3347 
3348 static int vt_unbind(struct con_driver *con)
3349 {
3350 	const struct consw *csw = NULL;
3351 	int i, more = 1, first = -1, last = -1, deflt = 0;
3352 	int ret;
3353 
3354  	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE))
3355 		goto err;
3356 
3357 	csw = con->con;
3358 
3359 	while (more) {
3360 		more = 0;
3361 
3362 		for (i = con->first; i <= con->last; i++) {
3363 			if (con_driver_map[i] == csw) {
3364 				if (first == -1)
3365 					first = i;
3366 				last = i;
3367 				more = 1;
3368 			} else if (first != -1)
3369 				break;
3370 		}
3371 
3372 		if (first == 0 && last == MAX_NR_CONSOLES -1)
3373 			deflt = 1;
3374 
3375 		if (first != -1) {
3376 			ret = do_unbind_con_driver(csw, first, last, deflt);
3377 			if (ret != 0)
3378 				return ret;
3379 		}
3380 
3381 		first = -1;
3382 		last = -1;
3383 		deflt = 0;
3384 	}
3385 
3386 err:
3387 	return 0;
3388 }
3389 #else
3390 static inline int vt_bind(struct con_driver *con)
3391 {
3392 	return 0;
3393 }
3394 static inline int vt_unbind(struct con_driver *con)
3395 {
3396 	return 0;
3397 }
3398 #endif /* CONFIG_VT_HW_CONSOLE_BINDING */
3399 
3400 static ssize_t store_bind(struct device *dev, struct device_attribute *attr,
3401 			  const char *buf, size_t count)
3402 {
3403 	struct con_driver *con = dev_get_drvdata(dev);
3404 	int bind = simple_strtoul(buf, NULL, 0);
3405 
3406 	console_lock();
3407 
3408 	if (bind)
3409 		vt_bind(con);
3410 	else
3411 		vt_unbind(con);
3412 
3413 	console_unlock();
3414 
3415 	return count;
3416 }
3417 
3418 static ssize_t show_bind(struct device *dev, struct device_attribute *attr,
3419 			 char *buf)
3420 {
3421 	struct con_driver *con = dev_get_drvdata(dev);
3422 	int bind = con_is_bound(con->con);
3423 
3424 	return snprintf(buf, PAGE_SIZE, "%i\n", bind);
3425 }
3426 
3427 static ssize_t show_name(struct device *dev, struct device_attribute *attr,
3428 			 char *buf)
3429 {
3430 	struct con_driver *con = dev_get_drvdata(dev);
3431 
3432 	return snprintf(buf, PAGE_SIZE, "%s %s\n",
3433 			(con->flag & CON_DRIVER_FLAG_MODULE) ? "(M)" : "(S)",
3434 			 con->desc);
3435 
3436 }
3437 
3438 static DEVICE_ATTR(bind, S_IRUGO|S_IWUSR, show_bind, store_bind);
3439 static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
3440 
3441 static struct attribute *con_dev_attrs[] = {
3442 	&dev_attr_bind.attr,
3443 	&dev_attr_name.attr,
3444 	NULL
3445 };
3446 
3447 ATTRIBUTE_GROUPS(con_dev);
3448 
3449 static int vtconsole_init_device(struct con_driver *con)
3450 {
3451 	con->flag |= CON_DRIVER_FLAG_ATTR;
3452 	return 0;
3453 }
3454 
3455 static void vtconsole_deinit_device(struct con_driver *con)
3456 {
3457 	con->flag &= ~CON_DRIVER_FLAG_ATTR;
3458 }
3459 
3460 /**
3461  * con_is_bound - checks if driver is bound to the console
3462  * @csw: console driver
3463  *
3464  * RETURNS: zero if unbound, nonzero if bound
3465  *
3466  * Drivers can call this and if zero, they should release
3467  * all resources allocated on con_startup()
3468  */
3469 int con_is_bound(const struct consw *csw)
3470 {
3471 	int i, bound = 0;
3472 
3473 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
3474 		if (con_driver_map[i] == csw) {
3475 			bound = 1;
3476 			break;
3477 		}
3478 	}
3479 
3480 	return bound;
3481 }
3482 EXPORT_SYMBOL(con_is_bound);
3483 
3484 /**
3485  * con_debug_enter - prepare the console for the kernel debugger
3486  * @sw: console driver
3487  *
3488  * Called when the console is taken over by the kernel debugger, this
3489  * function needs to save the current console state, then put the console
3490  * into a state suitable for the kernel debugger.
3491  *
3492  * RETURNS:
3493  * Zero on success, nonzero if a failure occurred when trying to prepare
3494  * the console for the debugger.
3495  */
3496 int con_debug_enter(struct vc_data *vc)
3497 {
3498 	int ret = 0;
3499 
3500 	saved_fg_console = fg_console;
3501 	saved_last_console = last_console;
3502 	saved_want_console = want_console;
3503 	saved_vc_mode = vc->vc_mode;
3504 	saved_console_blanked = console_blanked;
3505 	vc->vc_mode = KD_TEXT;
3506 	console_blanked = 0;
3507 	if (vc->vc_sw->con_debug_enter)
3508 		ret = vc->vc_sw->con_debug_enter(vc);
3509 #ifdef CONFIG_KGDB_KDB
3510 	/* Set the initial LINES variable if it is not already set */
3511 	if (vc->vc_rows < 999) {
3512 		int linecount;
3513 		char lns[4];
3514 		const char *setargs[3] = {
3515 			"set",
3516 			"LINES",
3517 			lns,
3518 		};
3519 		if (kdbgetintenv(setargs[0], &linecount)) {
3520 			snprintf(lns, 4, "%i", vc->vc_rows);
3521 			kdb_set(2, setargs);
3522 		}
3523 	}
3524 	if (vc->vc_cols < 999) {
3525 		int colcount;
3526 		char cols[4];
3527 		const char *setargs[3] = {
3528 			"set",
3529 			"COLUMNS",
3530 			cols,
3531 		};
3532 		if (kdbgetintenv(setargs[0], &colcount)) {
3533 			snprintf(cols, 4, "%i", vc->vc_cols);
3534 			kdb_set(2, setargs);
3535 		}
3536 	}
3537 #endif /* CONFIG_KGDB_KDB */
3538 	return ret;
3539 }
3540 EXPORT_SYMBOL_GPL(con_debug_enter);
3541 
3542 /**
3543  * con_debug_leave - restore console state
3544  * @sw: console driver
3545  *
3546  * Restore the console state to what it was before the kernel debugger
3547  * was invoked.
3548  *
3549  * RETURNS:
3550  * Zero on success, nonzero if a failure occurred when trying to restore
3551  * the console.
3552  */
3553 int con_debug_leave(void)
3554 {
3555 	struct vc_data *vc;
3556 	int ret = 0;
3557 
3558 	fg_console = saved_fg_console;
3559 	last_console = saved_last_console;
3560 	want_console = saved_want_console;
3561 	console_blanked = saved_console_blanked;
3562 	vc_cons[fg_console].d->vc_mode = saved_vc_mode;
3563 
3564 	vc = vc_cons[fg_console].d;
3565 	if (vc->vc_sw->con_debug_leave)
3566 		ret = vc->vc_sw->con_debug_leave(vc);
3567 	return ret;
3568 }
3569 EXPORT_SYMBOL_GPL(con_debug_leave);
3570 
3571 static int do_register_con_driver(const struct consw *csw, int first, int last)
3572 {
3573 	struct module *owner = csw->owner;
3574 	struct con_driver *con_driver;
3575 	const char *desc;
3576 	int i, retval;
3577 
3578 	WARN_CONSOLE_UNLOCKED();
3579 
3580 	if (!try_module_get(owner))
3581 		return -ENODEV;
3582 
3583 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3584 		con_driver = &registered_con_driver[i];
3585 
3586 		/* already registered */
3587 		if (con_driver->con == csw) {
3588 			retval = -EBUSY;
3589 			goto err;
3590 		}
3591 	}
3592 
3593 	desc = csw->con_startup();
3594 	if (!desc) {
3595 		retval = -ENODEV;
3596 		goto err;
3597 	}
3598 
3599 	retval = -EINVAL;
3600 
3601 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3602 		con_driver = &registered_con_driver[i];
3603 
3604 		if (con_driver->con == NULL &&
3605 		    !(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE)) {
3606 			con_driver->con = csw;
3607 			con_driver->desc = desc;
3608 			con_driver->node = i;
3609 			con_driver->flag = CON_DRIVER_FLAG_MODULE |
3610 			                   CON_DRIVER_FLAG_INIT;
3611 			con_driver->first = first;
3612 			con_driver->last = last;
3613 			retval = 0;
3614 			break;
3615 		}
3616 	}
3617 
3618 	if (retval)
3619 		goto err;
3620 
3621 	con_driver->dev =
3622 		device_create_with_groups(vtconsole_class, NULL,
3623 					  MKDEV(0, con_driver->node),
3624 					  con_driver, con_dev_groups,
3625 					  "vtcon%i", con_driver->node);
3626 	if (IS_ERR(con_driver->dev)) {
3627 		printk(KERN_WARNING "Unable to create device for %s; "
3628 		       "errno = %ld\n", con_driver->desc,
3629 		       PTR_ERR(con_driver->dev));
3630 		con_driver->dev = NULL;
3631 	} else {
3632 		vtconsole_init_device(con_driver);
3633 	}
3634 
3635 err:
3636 	module_put(owner);
3637 	return retval;
3638 }
3639 
3640 
3641 /**
3642  * do_unregister_con_driver - unregister console driver from console layer
3643  * @csw: console driver
3644  *
3645  * DESCRIPTION: All drivers that registers to the console layer must
3646  * call this function upon exit, or if the console driver is in a state
3647  * where it won't be able to handle console services, such as the
3648  * framebuffer console without loaded framebuffer drivers.
3649  *
3650  * The driver must unbind first prior to unregistration.
3651  */
3652 int do_unregister_con_driver(const struct consw *csw)
3653 {
3654 	int i;
3655 
3656 	/* cannot unregister a bound driver */
3657 	if (con_is_bound(csw))
3658 		return -EBUSY;
3659 
3660 	if (csw == conswitchp)
3661 		return -EINVAL;
3662 
3663 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3664 		struct con_driver *con_driver = &registered_con_driver[i];
3665 
3666 		if (con_driver->con == csw) {
3667 			/*
3668 			 * Defer the removal of the sysfs entries since that
3669 			 * will acquire the kernfs s_active lock and we can't
3670 			 * acquire this lock while holding the console lock:
3671 			 * the unbind sysfs entry imposes already the opposite
3672 			 * order. Reset con already here to prevent any later
3673 			 * lookup to succeed and mark this slot as zombie, so
3674 			 * it won't get reused until we complete the removal
3675 			 * in the deferred work.
3676 			 */
3677 			con_driver->con = NULL;
3678 			con_driver->flag = CON_DRIVER_FLAG_ZOMBIE;
3679 			schedule_work(&con_driver_unregister_work);
3680 
3681 			return 0;
3682 		}
3683 	}
3684 
3685 	return -ENODEV;
3686 }
3687 EXPORT_SYMBOL_GPL(do_unregister_con_driver);
3688 
3689 static void con_driver_unregister_callback(struct work_struct *ignored)
3690 {
3691 	int i;
3692 
3693 	console_lock();
3694 
3695 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3696 		struct con_driver *con_driver = &registered_con_driver[i];
3697 
3698 		if (!(con_driver->flag & CON_DRIVER_FLAG_ZOMBIE))
3699 			continue;
3700 
3701 		console_unlock();
3702 
3703 		vtconsole_deinit_device(con_driver);
3704 		device_destroy(vtconsole_class, MKDEV(0, con_driver->node));
3705 
3706 		console_lock();
3707 
3708 		if (WARN_ON_ONCE(con_driver->con))
3709 			con_driver->con = NULL;
3710 		con_driver->desc = NULL;
3711 		con_driver->dev = NULL;
3712 		con_driver->node = 0;
3713 		WARN_ON_ONCE(con_driver->flag != CON_DRIVER_FLAG_ZOMBIE);
3714 		con_driver->flag = 0;
3715 		con_driver->first = 0;
3716 		con_driver->last = 0;
3717 	}
3718 
3719 	console_unlock();
3720 }
3721 
3722 /*
3723  *	If we support more console drivers, this function is used
3724  *	when a driver wants to take over some existing consoles
3725  *	and become default driver for newly opened ones.
3726  *
3727  *	do_take_over_console is basically a register followed by unbind
3728  */
3729 int do_take_over_console(const struct consw *csw, int first, int last, int deflt)
3730 {
3731 	int err;
3732 
3733 	err = do_register_con_driver(csw, first, last);
3734 	/*
3735 	 * If we get an busy error we still want to bind the console driver
3736 	 * and return success, as we may have unbound the console driver
3737 	 * but not unregistered it.
3738 	 */
3739 	if (err == -EBUSY)
3740 		err = 0;
3741 	if (!err)
3742 		do_bind_con_driver(csw, first, last, deflt);
3743 
3744 	return err;
3745 }
3746 EXPORT_SYMBOL_GPL(do_take_over_console);
3747 
3748 
3749 /*
3750  * give_up_console is a wrapper to unregister_con_driver. It will only
3751  * work if driver is fully unbound.
3752  */
3753 void give_up_console(const struct consw *csw)
3754 {
3755 	console_lock();
3756 	do_unregister_con_driver(csw);
3757 	console_unlock();
3758 }
3759 
3760 static int __init vtconsole_class_init(void)
3761 {
3762 	int i;
3763 
3764 	vtconsole_class = class_create(THIS_MODULE, "vtconsole");
3765 	if (IS_ERR(vtconsole_class)) {
3766 		printk(KERN_WARNING "Unable to create vt console class; "
3767 		       "errno = %ld\n", PTR_ERR(vtconsole_class));
3768 		vtconsole_class = NULL;
3769 	}
3770 
3771 	/* Add system drivers to sysfs */
3772 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3773 		struct con_driver *con = &registered_con_driver[i];
3774 
3775 		if (con->con && !con->dev) {
3776 			con->dev =
3777 				device_create_with_groups(vtconsole_class, NULL,
3778 							  MKDEV(0, con->node),
3779 							  con, con_dev_groups,
3780 							  "vtcon%i", con->node);
3781 
3782 			if (IS_ERR(con->dev)) {
3783 				printk(KERN_WARNING "Unable to create "
3784 				       "device for %s; errno = %ld\n",
3785 				       con->desc, PTR_ERR(con->dev));
3786 				con->dev = NULL;
3787 			} else {
3788 				vtconsole_init_device(con);
3789 			}
3790 		}
3791 	}
3792 
3793 	return 0;
3794 }
3795 postcore_initcall(vtconsole_class_init);
3796 
3797 #endif
3798 
3799 /*
3800  *	Screen blanking
3801  */
3802 
3803 static int set_vesa_blanking(char __user *p)
3804 {
3805 	unsigned int mode;
3806 
3807 	if (get_user(mode, p + 1))
3808 		return -EFAULT;
3809 
3810 	vesa_blank_mode = (mode < 4) ? mode : 0;
3811 	return 0;
3812 }
3813 
3814 void do_blank_screen(int entering_gfx)
3815 {
3816 	struct vc_data *vc = vc_cons[fg_console].d;
3817 	int i;
3818 
3819 	WARN_CONSOLE_UNLOCKED();
3820 
3821 	if (console_blanked) {
3822 		if (blank_state == blank_vesa_wait) {
3823 			blank_state = blank_off;
3824 			vc->vc_sw->con_blank(vc, vesa_blank_mode + 1, 0);
3825 		}
3826 		return;
3827 	}
3828 
3829 	/* entering graphics mode? */
3830 	if (entering_gfx) {
3831 		hide_cursor(vc);
3832 		save_screen(vc);
3833 		vc->vc_sw->con_blank(vc, -1, 1);
3834 		console_blanked = fg_console + 1;
3835 		blank_state = blank_off;
3836 		set_origin(vc);
3837 		return;
3838 	}
3839 
3840 	if (blank_state != blank_normal_wait)
3841 		return;
3842 	blank_state = blank_off;
3843 
3844 	/* don't blank graphics */
3845 	if (vc->vc_mode != KD_TEXT) {
3846 		console_blanked = fg_console + 1;
3847 		return;
3848 	}
3849 
3850 	hide_cursor(vc);
3851 	del_timer_sync(&console_timer);
3852 	blank_timer_expired = 0;
3853 
3854 	save_screen(vc);
3855 	/* In case we need to reset origin, blanking hook returns 1 */
3856 	i = vc->vc_sw->con_blank(vc, vesa_off_interval ? 1 : (vesa_blank_mode + 1), 0);
3857 	console_blanked = fg_console + 1;
3858 	if (i)
3859 		set_origin(vc);
3860 
3861 	if (console_blank_hook && console_blank_hook(1))
3862 		return;
3863 
3864 	if (vesa_off_interval && vesa_blank_mode) {
3865 		blank_state = blank_vesa_wait;
3866 		mod_timer(&console_timer, jiffies + vesa_off_interval);
3867 	}
3868 	vt_event_post(VT_EVENT_BLANK, vc->vc_num, vc->vc_num);
3869 }
3870 EXPORT_SYMBOL(do_blank_screen);
3871 
3872 /*
3873  * Called by timer as well as from vt_console_driver
3874  */
3875 void do_unblank_screen(int leaving_gfx)
3876 {
3877 	struct vc_data *vc;
3878 
3879 	/* This should now always be called from a "sane" (read: can schedule)
3880 	 * context for the sake of the low level drivers, except in the special
3881 	 * case of oops_in_progress
3882 	 */
3883 	if (!oops_in_progress)
3884 		might_sleep();
3885 
3886 	WARN_CONSOLE_UNLOCKED();
3887 
3888 	ignore_poke = 0;
3889 	if (!console_blanked)
3890 		return;
3891 	if (!vc_cons_allocated(fg_console)) {
3892 		/* impossible */
3893 		pr_warn("unblank_screen: tty %d not allocated ??\n",
3894 			fg_console + 1);
3895 		return;
3896 	}
3897 	vc = vc_cons[fg_console].d;
3898 	/* Try to unblank in oops case too */
3899 	if (vc->vc_mode != KD_TEXT && !vt_force_oops_output(vc))
3900 		return; /* but leave console_blanked != 0 */
3901 
3902 	if (blankinterval) {
3903 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3904 		blank_state = blank_normal_wait;
3905 	}
3906 
3907 	console_blanked = 0;
3908 	if (vc->vc_sw->con_blank(vc, 0, leaving_gfx) || vt_force_oops_output(vc))
3909 		/* Low-level driver cannot restore -> do it ourselves */
3910 		update_screen(vc);
3911 	if (console_blank_hook)
3912 		console_blank_hook(0);
3913 	set_palette(vc);
3914 	set_cursor(vc);
3915 	vt_event_post(VT_EVENT_UNBLANK, vc->vc_num, vc->vc_num);
3916 }
3917 EXPORT_SYMBOL(do_unblank_screen);
3918 
3919 /*
3920  * This is called by the outside world to cause a forced unblank, mostly for
3921  * oopses. Currently, I just call do_unblank_screen(0), but we could eventually
3922  * call it with 1 as an argument and so force a mode restore... that may kill
3923  * X or at least garbage the screen but would also make the Oops visible...
3924  */
3925 void unblank_screen(void)
3926 {
3927 	do_unblank_screen(0);
3928 }
3929 
3930 /*
3931  * We defer the timer blanking to work queue so it can take the console mutex
3932  * (console operations can still happen at irq time, but only from printk which
3933  * has the console mutex. Not perfect yet, but better than no locking
3934  */
3935 static void blank_screen_t(unsigned long dummy)
3936 {
3937 	if (unlikely(!keventd_up())) {
3938 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3939 		return;
3940 	}
3941 	blank_timer_expired = 1;
3942 	schedule_work(&console_work);
3943 }
3944 
3945 void poke_blanked_console(void)
3946 {
3947 	WARN_CONSOLE_UNLOCKED();
3948 
3949 	/* Add this so we quickly catch whoever might call us in a non
3950 	 * safe context. Nowadays, unblank_screen() isn't to be called in
3951 	 * atomic contexts and is allowed to schedule (with the special case
3952 	 * of oops_in_progress, but that isn't of any concern for this
3953 	 * function. --BenH.
3954 	 */
3955 	might_sleep();
3956 
3957 	/* This isn't perfectly race free, but a race here would be mostly harmless,
3958 	 * at worse, we'll do a spurrious blank and it's unlikely
3959 	 */
3960 	del_timer(&console_timer);
3961 	blank_timer_expired = 0;
3962 
3963 	if (ignore_poke || !vc_cons[fg_console].d || vc_cons[fg_console].d->vc_mode == KD_GRAPHICS)
3964 		return;
3965 	if (console_blanked)
3966 		unblank_screen();
3967 	else if (blankinterval) {
3968 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3969 		blank_state = blank_normal_wait;
3970 	}
3971 }
3972 
3973 /*
3974  *	Palettes
3975  */
3976 
3977 static void set_palette(struct vc_data *vc)
3978 {
3979 	WARN_CONSOLE_UNLOCKED();
3980 
3981 	if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_set_palette)
3982 		vc->vc_sw->con_set_palette(vc, color_table);
3983 }
3984 
3985 /*
3986  * Load palette into the DAC registers. arg points to a colour
3987  * map, 3 bytes per colour, 16 colours, range from 0 to 255.
3988  */
3989 
3990 int con_set_cmap(unsigned char __user *arg)
3991 {
3992 	int i, j, k;
3993 	unsigned char colormap[3*16];
3994 
3995 	if (copy_from_user(colormap, arg, sizeof(colormap)))
3996 		return -EFAULT;
3997 
3998 	console_lock();
3999 	for (i = k = 0; i < 16; i++) {
4000 		default_red[i] = colormap[k++];
4001 		default_grn[i] = colormap[k++];
4002 		default_blu[i] = colormap[k++];
4003 	}
4004 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
4005 		if (!vc_cons_allocated(i))
4006 			continue;
4007 		for (j = k = 0; j < 16; j++) {
4008 			vc_cons[i].d->vc_palette[k++] = default_red[j];
4009 			vc_cons[i].d->vc_palette[k++] = default_grn[j];
4010 			vc_cons[i].d->vc_palette[k++] = default_blu[j];
4011 		}
4012 		set_palette(vc_cons[i].d);
4013 	}
4014 	console_unlock();
4015 
4016 	return 0;
4017 }
4018 
4019 int con_get_cmap(unsigned char __user *arg)
4020 {
4021 	int i, k;
4022 	unsigned char colormap[3*16];
4023 
4024 	console_lock();
4025 	for (i = k = 0; i < 16; i++) {
4026 		colormap[k++] = default_red[i];
4027 		colormap[k++] = default_grn[i];
4028 		colormap[k++] = default_blu[i];
4029 	}
4030 	console_unlock();
4031 
4032 	if (copy_to_user(arg, colormap, sizeof(colormap)))
4033 		return -EFAULT;
4034 
4035 	return 0;
4036 }
4037 
4038 void reset_palette(struct vc_data *vc)
4039 {
4040 	int j, k;
4041 	for (j=k=0; j<16; j++) {
4042 		vc->vc_palette[k++] = default_red[j];
4043 		vc->vc_palette[k++] = default_grn[j];
4044 		vc->vc_palette[k++] = default_blu[j];
4045 	}
4046 	set_palette(vc);
4047 }
4048 
4049 /*
4050  *  Font switching
4051  *
4052  *  Currently we only support fonts up to 32 pixels wide, at a maximum height
4053  *  of 32 pixels. Userspace fontdata is stored with 32 bytes (shorts/ints,
4054  *  depending on width) reserved for each character which is kinda wasty, but
4055  *  this is done in order to maintain compatibility with the EGA/VGA fonts. It
4056  *  is up to the actual low-level console-driver convert data into its favorite
4057  *  format (maybe we should add a `fontoffset' field to the `display'
4058  *  structure so we won't have to convert the fontdata all the time.
4059  *  /Jes
4060  */
4061 
4062 #define max_font_size 65536
4063 
4064 static int con_font_get(struct vc_data *vc, struct console_font_op *op)
4065 {
4066 	struct console_font font;
4067 	int rc = -EINVAL;
4068 	int c;
4069 
4070 	if (op->data) {
4071 		font.data = kmalloc(max_font_size, GFP_KERNEL);
4072 		if (!font.data)
4073 			return -ENOMEM;
4074 	} else
4075 		font.data = NULL;
4076 
4077 	console_lock();
4078 	if (vc->vc_mode != KD_TEXT)
4079 		rc = -EINVAL;
4080 	else if (vc->vc_sw->con_font_get)
4081 		rc = vc->vc_sw->con_font_get(vc, &font);
4082 	else
4083 		rc = -ENOSYS;
4084 	console_unlock();
4085 
4086 	if (rc)
4087 		goto out;
4088 
4089 	c = (font.width+7)/8 * 32 * font.charcount;
4090 
4091 	if (op->data && font.charcount > op->charcount)
4092 		rc = -ENOSPC;
4093 	if (!(op->flags & KD_FONT_FLAG_OLD)) {
4094 		if (font.width > op->width || font.height > op->height)
4095 			rc = -ENOSPC;
4096 	} else {
4097 		if (font.width != 8)
4098 			rc = -EIO;
4099 		else if ((op->height && font.height > op->height) ||
4100 			 font.height > 32)
4101 			rc = -ENOSPC;
4102 	}
4103 	if (rc)
4104 		goto out;
4105 
4106 	op->height = font.height;
4107 	op->width = font.width;
4108 	op->charcount = font.charcount;
4109 
4110 	if (op->data && copy_to_user(op->data, font.data, c))
4111 		rc = -EFAULT;
4112 
4113 out:
4114 	kfree(font.data);
4115 	return rc;
4116 }
4117 
4118 static int con_font_set(struct vc_data *vc, struct console_font_op *op)
4119 {
4120 	struct console_font font;
4121 	int rc = -EINVAL;
4122 	int size;
4123 
4124 	if (vc->vc_mode != KD_TEXT)
4125 		return -EINVAL;
4126 	if (!op->data)
4127 		return -EINVAL;
4128 	if (op->charcount > 512)
4129 		return -EINVAL;
4130 	if (!op->height) {		/* Need to guess font height [compat] */
4131 		int h, i;
4132 		u8 __user *charmap = op->data;
4133 		u8 tmp;
4134 
4135 		/* If from KDFONTOP ioctl, don't allow things which can be done in userland,
4136 		   so that we can get rid of this soon */
4137 		if (!(op->flags & KD_FONT_FLAG_OLD))
4138 			return -EINVAL;
4139 		for (h = 32; h > 0; h--)
4140 			for (i = 0; i < op->charcount; i++) {
4141 				if (get_user(tmp, &charmap[32*i+h-1]))
4142 					return -EFAULT;
4143 				if (tmp)
4144 					goto nonzero;
4145 			}
4146 		return -EINVAL;
4147 	nonzero:
4148 		op->height = h;
4149 	}
4150 	if (op->width <= 0 || op->width > 32 || op->height > 32)
4151 		return -EINVAL;
4152 	size = (op->width+7)/8 * 32 * op->charcount;
4153 	if (size > max_font_size)
4154 		return -ENOSPC;
4155 	font.charcount = op->charcount;
4156 	font.height = op->height;
4157 	font.width = op->width;
4158 	font.data = memdup_user(op->data, size);
4159 	if (IS_ERR(font.data))
4160 		return PTR_ERR(font.data);
4161 	console_lock();
4162 	if (vc->vc_mode != KD_TEXT)
4163 		rc = -EINVAL;
4164 	else if (vc->vc_sw->con_font_set)
4165 		rc = vc->vc_sw->con_font_set(vc, &font, op->flags);
4166 	else
4167 		rc = -ENOSYS;
4168 	console_unlock();
4169 	kfree(font.data);
4170 	return rc;
4171 }
4172 
4173 static int con_font_default(struct vc_data *vc, struct console_font_op *op)
4174 {
4175 	struct console_font font = {.width = op->width, .height = op->height};
4176 	char name[MAX_FONT_NAME];
4177 	char *s = name;
4178 	int rc;
4179 
4180 
4181 	if (!op->data)
4182 		s = NULL;
4183 	else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0)
4184 		return -EFAULT;
4185 	else
4186 		name[MAX_FONT_NAME - 1] = 0;
4187 
4188 	console_lock();
4189 	if (vc->vc_mode != KD_TEXT) {
4190 		console_unlock();
4191 		return -EINVAL;
4192 	}
4193 	if (vc->vc_sw->con_font_default)
4194 		rc = vc->vc_sw->con_font_default(vc, &font, s);
4195 	else
4196 		rc = -ENOSYS;
4197 	console_unlock();
4198 	if (!rc) {
4199 		op->width = font.width;
4200 		op->height = font.height;
4201 	}
4202 	return rc;
4203 }
4204 
4205 static int con_font_copy(struct vc_data *vc, struct console_font_op *op)
4206 {
4207 	int con = op->height;
4208 	int rc;
4209 
4210 
4211 	console_lock();
4212 	if (vc->vc_mode != KD_TEXT)
4213 		rc = -EINVAL;
4214 	else if (!vc->vc_sw->con_font_copy)
4215 		rc = -ENOSYS;
4216 	else if (con < 0 || !vc_cons_allocated(con))
4217 		rc = -ENOTTY;
4218 	else if (con == vc->vc_num)	/* nothing to do */
4219 		rc = 0;
4220 	else
4221 		rc = vc->vc_sw->con_font_copy(vc, con);
4222 	console_unlock();
4223 	return rc;
4224 }
4225 
4226 int con_font_op(struct vc_data *vc, struct console_font_op *op)
4227 {
4228 	switch (op->op) {
4229 	case KD_FONT_OP_SET:
4230 		return con_font_set(vc, op);
4231 	case KD_FONT_OP_GET:
4232 		return con_font_get(vc, op);
4233 	case KD_FONT_OP_SET_DEFAULT:
4234 		return con_font_default(vc, op);
4235 	case KD_FONT_OP_COPY:
4236 		return con_font_copy(vc, op);
4237 	}
4238 	return -ENOSYS;
4239 }
4240 
4241 /*
4242  *	Interface exported to selection and vcs.
4243  */
4244 
4245 /* used by selection */
4246 u16 screen_glyph(struct vc_data *vc, int offset)
4247 {
4248 	u16 w = scr_readw(screenpos(vc, offset, 1));
4249 	u16 c = w & 0xff;
4250 
4251 	if (w & vc->vc_hi_font_mask)
4252 		c |= 0x100;
4253 	return c;
4254 }
4255 EXPORT_SYMBOL_GPL(screen_glyph);
4256 
4257 /* used by vcs - note the word offset */
4258 unsigned short *screen_pos(struct vc_data *vc, int w_offset, int viewed)
4259 {
4260 	return screenpos(vc, 2 * w_offset, viewed);
4261 }
4262 EXPORT_SYMBOL_GPL(screen_pos);
4263 
4264 void getconsxy(struct vc_data *vc, unsigned char *p)
4265 {
4266 	p[0] = vc->vc_x;
4267 	p[1] = vc->vc_y;
4268 }
4269 
4270 void putconsxy(struct vc_data *vc, unsigned char *p)
4271 {
4272 	hide_cursor(vc);
4273 	gotoxy(vc, p[0], p[1]);
4274 	set_cursor(vc);
4275 }
4276 
4277 u16 vcs_scr_readw(struct vc_data *vc, const u16 *org)
4278 {
4279 	if ((unsigned long)org == vc->vc_pos && softcursor_original != -1)
4280 		return softcursor_original;
4281 	return scr_readw(org);
4282 }
4283 
4284 void vcs_scr_writew(struct vc_data *vc, u16 val, u16 *org)
4285 {
4286 	scr_writew(val, org);
4287 	if ((unsigned long)org == vc->vc_pos) {
4288 		softcursor_original = -1;
4289 		add_softcursor(vc);
4290 	}
4291 }
4292 
4293 void vcs_scr_updated(struct vc_data *vc)
4294 {
4295 	notify_update(vc);
4296 }
4297 
4298 /*
4299  *	Visible symbols for modules
4300  */
4301 
4302 EXPORT_SYMBOL(color_table);
4303 EXPORT_SYMBOL(default_red);
4304 EXPORT_SYMBOL(default_grn);
4305 EXPORT_SYMBOL(default_blu);
4306 EXPORT_SYMBOL(update_region);
4307 EXPORT_SYMBOL(redraw_screen);
4308 EXPORT_SYMBOL(vc_resize);
4309 EXPORT_SYMBOL(fg_console);
4310 EXPORT_SYMBOL(console_blank_hook);
4311 EXPORT_SYMBOL(console_blanked);
4312 EXPORT_SYMBOL(vc_cons);
4313 EXPORT_SYMBOL(global_cursor_default);
4314 #ifndef VT_SINGLE_DRIVER
4315 EXPORT_SYMBOL(give_up_console);
4316 #endif
4317