xref: /openbmc/linux/drivers/tty/vt/vt.c (revision c819e2cf)
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 
112 struct con_driver {
113 	const struct consw *con;
114 	const char *desc;
115 	struct device *dev;
116 	int node;
117 	int first;
118 	int last;
119 	int flag;
120 };
121 
122 static struct con_driver registered_con_driver[MAX_NR_CON_DRIVER];
123 const struct consw *conswitchp;
124 
125 /* A bitmap for codes <32. A bit of 1 indicates that the code
126  * corresponding to that bit number invokes some special action
127  * (such as cursor movement) and should not be displayed as a
128  * glyph unless the disp_ctrl mode is explicitly enabled.
129  */
130 #define CTRL_ACTION 0x0d00ff81
131 #define CTRL_ALWAYS 0x0800f501	/* Cannot be overridden by disp_ctrl */
132 
133 /*
134  * Here is the default bell parameters: 750HZ, 1/8th of a second
135  */
136 #define DEFAULT_BELL_PITCH	750
137 #define DEFAULT_BELL_DURATION	(HZ/8)
138 
139 struct vc vc_cons [MAX_NR_CONSOLES];
140 
141 #ifndef VT_SINGLE_DRIVER
142 static const struct consw *con_driver_map[MAX_NR_CONSOLES];
143 #endif
144 
145 static int con_open(struct tty_struct *, struct file *);
146 static void vc_init(struct vc_data *vc, unsigned int rows,
147 		    unsigned int cols, int do_clear);
148 static void gotoxy(struct vc_data *vc, int new_x, int new_y);
149 static void save_cur(struct vc_data *vc);
150 static void reset_terminal(struct vc_data *vc, int do_clear);
151 static void con_flush_chars(struct tty_struct *tty);
152 static int set_vesa_blanking(char __user *p);
153 static void set_cursor(struct vc_data *vc);
154 static void hide_cursor(struct vc_data *vc);
155 static void console_callback(struct work_struct *ignored);
156 static void blank_screen_t(unsigned long dummy);
157 static void set_palette(struct vc_data *vc);
158 
159 #define vt_get_kmsg_redirect() vt_kmsg_redirect(-1)
160 
161 static int printable;		/* Is console ready for printing? */
162 int default_utf8 = true;
163 module_param(default_utf8, int, S_IRUGO | S_IWUSR);
164 int global_cursor_default = -1;
165 module_param(global_cursor_default, int, S_IRUGO | S_IWUSR);
166 
167 static int cur_default = CUR_DEFAULT;
168 module_param(cur_default, int, S_IRUGO | S_IWUSR);
169 
170 /*
171  * ignore_poke: don't unblank the screen when things are typed.  This is
172  * mainly for the privacy of braille terminal users.
173  */
174 static int ignore_poke;
175 
176 int do_poke_blanked_console;
177 int console_blanked;
178 
179 static int vesa_blank_mode; /* 0:none 1:suspendV 2:suspendH 3:powerdown */
180 static int vesa_off_interval;
181 static int blankinterval = 10*60;
182 core_param(consoleblank, blankinterval, int, 0444);
183 
184 static DECLARE_WORK(console_work, console_callback);
185 
186 /*
187  * fg_console is the current virtual console,
188  * last_console is the last used one,
189  * want_console is the console we want to switch to,
190  * saved_* variants are for save/restore around kernel debugger enter/leave
191  */
192 int fg_console;
193 int last_console;
194 int want_console = -1;
195 static int saved_fg_console;
196 static int saved_last_console;
197 static int saved_want_console;
198 static int saved_vc_mode;
199 static int saved_console_blanked;
200 
201 /*
202  * For each existing display, we have a pointer to console currently visible
203  * on that display, allowing consoles other than fg_console to be refreshed
204  * appropriately. Unless the low-level driver supplies its own display_fg
205  * variable, we use this one for the "master display".
206  */
207 static struct vc_data *master_display_fg;
208 
209 /*
210  * Unfortunately, we need to delay tty echo when we're currently writing to the
211  * console since the code is (and always was) not re-entrant, so we schedule
212  * all flip requests to process context with schedule-task() and run it from
213  * console_callback().
214  */
215 
216 /*
217  * For the same reason, we defer scrollback to the console callback.
218  */
219 static int scrollback_delta;
220 
221 /*
222  * Hook so that the power management routines can (un)blank
223  * the console on our behalf.
224  */
225 int (*console_blank_hook)(int);
226 
227 static DEFINE_TIMER(console_timer, blank_screen_t, 0, 0);
228 static int blank_state;
229 static int blank_timer_expired;
230 enum {
231 	blank_off = 0,
232 	blank_normal_wait,
233 	blank_vesa_wait,
234 };
235 
236 /*
237  * /sys/class/tty/tty0/
238  *
239  * the attribute 'active' contains the name of the current vc
240  * console and it supports poll() to detect vc switches
241  */
242 static struct device *tty0dev;
243 
244 /*
245  * Notifier list for console events.
246  */
247 static ATOMIC_NOTIFIER_HEAD(vt_notifier_list);
248 
249 int register_vt_notifier(struct notifier_block *nb)
250 {
251 	return atomic_notifier_chain_register(&vt_notifier_list, nb);
252 }
253 EXPORT_SYMBOL_GPL(register_vt_notifier);
254 
255 int unregister_vt_notifier(struct notifier_block *nb)
256 {
257 	return atomic_notifier_chain_unregister(&vt_notifier_list, nb);
258 }
259 EXPORT_SYMBOL_GPL(unregister_vt_notifier);
260 
261 static void notify_write(struct vc_data *vc, unsigned int unicode)
262 {
263 	struct vt_notifier_param param = { .vc = vc, .c = unicode };
264 	atomic_notifier_call_chain(&vt_notifier_list, VT_WRITE, &param);
265 }
266 
267 static void notify_update(struct vc_data *vc)
268 {
269 	struct vt_notifier_param param = { .vc = vc };
270 	atomic_notifier_call_chain(&vt_notifier_list, VT_UPDATE, &param);
271 }
272 /*
273  *	Low-Level Functions
274  */
275 
276 #define IS_FG(vc)	((vc)->vc_num == fg_console)
277 
278 #ifdef VT_BUF_VRAM_ONLY
279 #define DO_UPDATE(vc)	0
280 #else
281 #define DO_UPDATE(vc)	(CON_IS_VISIBLE(vc) && !console_blanked)
282 #endif
283 
284 static inline unsigned short *screenpos(struct vc_data *vc, int offset, int viewed)
285 {
286 	unsigned short *p;
287 
288 	if (!viewed)
289 		p = (unsigned short *)(vc->vc_origin + offset);
290 	else if (!vc->vc_sw->con_screen_pos)
291 		p = (unsigned short *)(vc->vc_visible_origin + offset);
292 	else
293 		p = vc->vc_sw->con_screen_pos(vc, offset);
294 	return p;
295 }
296 
297 /* Called  from the keyboard irq path.. */
298 static inline void scrolldelta(int lines)
299 {
300 	/* FIXME */
301 	/* scrolldelta needs some kind of consistency lock, but the BKL was
302 	   and still is not protecting versus the scheduled back end */
303 	scrollback_delta += lines;
304 	schedule_console_callback();
305 }
306 
307 void schedule_console_callback(void)
308 {
309 	schedule_work(&console_work);
310 }
311 
312 static void scrup(struct vc_data *vc, unsigned int t, unsigned int b, int nr)
313 {
314 	unsigned short *d, *s;
315 
316 	if (t+nr >= b)
317 		nr = b - t - 1;
318 	if (b > vc->vc_rows || t >= b || nr < 1)
319 		return;
320 	if (CON_IS_VISIBLE(vc) && vc->vc_sw->con_scroll(vc, t, b, SM_UP, nr))
321 		return;
322 	d = (unsigned short *)(vc->vc_origin + vc->vc_size_row * t);
323 	s = (unsigned short *)(vc->vc_origin + vc->vc_size_row * (t + nr));
324 	scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
325 	scr_memsetw(d + (b - t - nr) * vc->vc_cols, vc->vc_video_erase_char,
326 		    vc->vc_size_row * nr);
327 }
328 
329 static void scrdown(struct vc_data *vc, unsigned int t, unsigned int b, int nr)
330 {
331 	unsigned short *s;
332 	unsigned int step;
333 
334 	if (t+nr >= b)
335 		nr = b - t - 1;
336 	if (b > vc->vc_rows || t >= b || nr < 1)
337 		return;
338 	if (CON_IS_VISIBLE(vc) && vc->vc_sw->con_scroll(vc, t, b, SM_DOWN, nr))
339 		return;
340 	s = (unsigned short *)(vc->vc_origin + vc->vc_size_row * t);
341 	step = vc->vc_cols * nr;
342 	scr_memmovew(s + step, s, (b - t - nr) * vc->vc_size_row);
343 	scr_memsetw(s, vc->vc_video_erase_char, 2 * step);
344 }
345 
346 static void do_update_region(struct vc_data *vc, unsigned long start, int count)
347 {
348 #ifndef VT_BUF_VRAM_ONLY
349 	unsigned int xx, yy, offset;
350 	u16 *p;
351 
352 	p = (u16 *) start;
353 	if (!vc->vc_sw->con_getxy) {
354 		offset = (start - vc->vc_origin) / 2;
355 		xx = offset % vc->vc_cols;
356 		yy = offset / vc->vc_cols;
357 	} else {
358 		int nxx, nyy;
359 		start = vc->vc_sw->con_getxy(vc, start, &nxx, &nyy);
360 		xx = nxx; yy = nyy;
361 	}
362 	for(;;) {
363 		u16 attrib = scr_readw(p) & 0xff00;
364 		int startx = xx;
365 		u16 *q = p;
366 		while (xx < vc->vc_cols && count) {
367 			if (attrib != (scr_readw(p) & 0xff00)) {
368 				if (p > q)
369 					vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
370 				startx = xx;
371 				q = p;
372 				attrib = scr_readw(p) & 0xff00;
373 			}
374 			p++;
375 			xx++;
376 			count--;
377 		}
378 		if (p > q)
379 			vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
380 		if (!count)
381 			break;
382 		xx = 0;
383 		yy++;
384 		if (vc->vc_sw->con_getxy) {
385 			p = (u16 *)start;
386 			start = vc->vc_sw->con_getxy(vc, start, NULL, NULL);
387 		}
388 	}
389 #endif
390 }
391 
392 void update_region(struct vc_data *vc, unsigned long start, int count)
393 {
394 	WARN_CONSOLE_UNLOCKED();
395 
396 	if (DO_UPDATE(vc)) {
397 		hide_cursor(vc);
398 		do_update_region(vc, start, count);
399 		set_cursor(vc);
400 	}
401 }
402 
403 /* Structure of attributes is hardware-dependent */
404 
405 static u8 build_attr(struct vc_data *vc, u8 _color, u8 _intensity, u8 _blink,
406     u8 _underline, u8 _reverse, u8 _italic)
407 {
408 	if (vc->vc_sw->con_build_attr)
409 		return vc->vc_sw->con_build_attr(vc, _color, _intensity,
410 		       _blink, _underline, _reverse, _italic);
411 
412 #ifndef VT_BUF_VRAM_ONLY
413 /*
414  * ++roman: I completely changed the attribute format for monochrome
415  * mode (!can_do_color). The formerly used MDA (monochrome display
416  * adapter) format didn't allow the combination of certain effects.
417  * Now the attribute is just a bit vector:
418  *  Bit 0..1: intensity (0..2)
419  *  Bit 2   : underline
420  *  Bit 3   : reverse
421  *  Bit 7   : blink
422  */
423 	{
424 	u8 a = _color;
425 	if (!vc->vc_can_do_color)
426 		return _intensity |
427 		       (_italic ? 2 : 0) |
428 		       (_underline ? 4 : 0) |
429 		       (_reverse ? 8 : 0) |
430 		       (_blink ? 0x80 : 0);
431 	if (_italic)
432 		a = (a & 0xF0) | vc->vc_itcolor;
433 	else if (_underline)
434 		a = (a & 0xf0) | vc->vc_ulcolor;
435 	else if (_intensity == 0)
436 		a = (a & 0xf0) | vc->vc_ulcolor;
437 	if (_reverse)
438 		a = ((a) & 0x88) | ((((a) >> 4) | ((a) << 4)) & 0x77);
439 	if (_blink)
440 		a ^= 0x80;
441 	if (_intensity == 2)
442 		a ^= 0x08;
443 	if (vc->vc_hi_font_mask == 0x100)
444 		a <<= 1;
445 	return a;
446 	}
447 #else
448 	return 0;
449 #endif
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 #ifndef VT_BUF_VRAM_ONLY
472 	else {
473 		u16 *q = p;
474 		int cnt = count;
475 		u16 a;
476 
477 		if (!vc->vc_can_do_color) {
478 			while (cnt--) {
479 			    a = scr_readw(q);
480 			    a ^= 0x0800;
481 			    scr_writew(a, q);
482 			    q++;
483 			}
484 		} else if (vc->vc_hi_font_mask == 0x100) {
485 			while (cnt--) {
486 				a = scr_readw(q);
487 				a = ((a) & 0x11ff) | (((a) & 0xe000) >> 4) | (((a) & 0x0e00) << 4);
488 				scr_writew(a, q);
489 				q++;
490 			}
491 		} else {
492 			while (cnt--) {
493 				a = scr_readw(q);
494 				a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) | (((a) & 0x0700) << 4);
495 				scr_writew(a, q);
496 				q++;
497 			}
498 		}
499 	}
500 #endif
501 	if (DO_UPDATE(vc))
502 		do_update_region(vc, (unsigned long) p, count);
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 (DO_UPDATE(vc))
518 			vc->vc_sw->con_putc(vc, old, oldy, oldx);
519 	}
520 
521 	old_offset = offset;
522 
523 	if (offset != -1 && offset >= 0 &&
524 	    offset < vc->vc_screenbuf_size) {
525 		unsigned short new;
526 		unsigned short *p;
527 		p = screenpos(vc, offset, 1);
528 		old = scr_readw(p);
529 		new = old ^ vc->vc_complement_mask;
530 		scr_writew(new, p);
531 		if (DO_UPDATE(vc)) {
532 			oldx = (offset >> 1) % vc->vc_cols;
533 			oldy = (offset >> 1) / vc->vc_cols;
534 			vc->vc_sw->con_putc(vc, new, oldy, oldx);
535 		}
536 	}
537 
538 }
539 
540 static void insert_char(struct vc_data *vc, unsigned int nr)
541 {
542 	unsigned short *p = (unsigned short *) vc->vc_pos;
543 
544 	scr_memmovew(p + nr, p, (vc->vc_cols - vc->vc_x - nr) * 2);
545 	scr_memsetw(p, vc->vc_video_erase_char, nr * 2);
546 	vc->vc_need_wrap = 0;
547 	if (DO_UPDATE(vc))
548 		do_update_region(vc, (unsigned long) p,
549 			vc->vc_cols - vc->vc_x);
550 }
551 
552 static void delete_char(struct vc_data *vc, unsigned int nr)
553 {
554 	unsigned short *p = (unsigned short *) vc->vc_pos;
555 
556 	scr_memcpyw(p, p + nr, (vc->vc_cols - vc->vc_x - nr) * 2);
557 	scr_memsetw(p + vc->vc_cols - vc->vc_x - nr, vc->vc_video_erase_char,
558 			nr * 2);
559 	vc->vc_need_wrap = 0;
560 	if (DO_UPDATE(vc))
561 		do_update_region(vc, (unsigned long) p,
562 			vc->vc_cols - vc->vc_x);
563 }
564 
565 static int softcursor_original;
566 
567 static void add_softcursor(struct vc_data *vc)
568 {
569 	int i = scr_readw((u16 *) vc->vc_pos);
570 	u32 type = vc->vc_cursor_type;
571 
572 	if (! (type & 0x10)) return;
573 	if (softcursor_original != -1) return;
574 	softcursor_original = i;
575 	i |= ((type >> 8) & 0xff00 );
576 	i ^= ((type) & 0xff00 );
577 	if ((type & 0x20) && ((softcursor_original & 0x7000) == (i & 0x7000))) i ^= 0x7000;
578 	if ((type & 0x40) && ((i & 0x700) == ((i & 0x7000) >> 4))) i ^= 0x0700;
579 	scr_writew(i, (u16 *) vc->vc_pos);
580 	if (DO_UPDATE(vc))
581 		vc->vc_sw->con_putc(vc, i, vc->vc_y, vc->vc_x);
582 }
583 
584 static void hide_softcursor(struct vc_data *vc)
585 {
586 	if (softcursor_original != -1) {
587 		scr_writew(softcursor_original, (u16 *)vc->vc_pos);
588 		if (DO_UPDATE(vc))
589 			vc->vc_sw->con_putc(vc, softcursor_original,
590 					vc->vc_y, vc->vc_x);
591 		softcursor_original = -1;
592 	}
593 }
594 
595 static void hide_cursor(struct vc_data *vc)
596 {
597 	if (vc == sel_cons)
598 		clear_selection();
599 	vc->vc_sw->con_cursor(vc, CM_ERASE);
600 	hide_softcursor(vc);
601 }
602 
603 static void set_cursor(struct vc_data *vc)
604 {
605 	if (!IS_FG(vc) || console_blanked ||
606 	    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 inline 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 	vc->vc_uni_pagedir_loc = &vc->vc_uni_pagedir;
740 	vc->vc_uni_pagedir = NULL;
741 	vc->vc_hi_font_mask = 0;
742 	vc->vc_complement_mask = 0;
743 	vc->vc_can_do_color = 0;
744 	vc->vc_panic_force_write = false;
745 	vc->vc_sw->con_init(vc, init);
746 	if (!vc->vc_complement_mask)
747 		vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
748 	vc->vc_s_complement_mask = vc->vc_complement_mask;
749 	vc->vc_size_row = vc->vc_cols << 1;
750 	vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
751 }
752 
753 int vc_allocate(unsigned int currcons)	/* return 0 on success */
754 {
755 	WARN_CONSOLE_UNLOCKED();
756 
757 	if (currcons >= MAX_NR_CONSOLES)
758 		return -ENXIO;
759 	if (!vc_cons[currcons].d) {
760 	    struct vc_data *vc;
761 	    struct vt_notifier_param param;
762 
763 	    /* prevent users from taking too much memory */
764 	    if (currcons >= MAX_NR_USER_CONSOLES && !capable(CAP_SYS_RESOURCE))
765 	      return -EPERM;
766 
767 	    /* due to the granularity of kmalloc, we waste some memory here */
768 	    /* the alloc is done in two steps, to optimize the common situation
769 	       of a 25x80 console (structsize=216, screenbuf_size=4000) */
770 	    /* although the numbers above are not valid since long ago, the
771 	       point is still up-to-date and the comment still has its value
772 	       even if only as a historical artifact.  --mj, July 1998 */
773 	    param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL);
774 	    if (!vc)
775 		return -ENOMEM;
776 	    vc_cons[currcons].d = vc;
777 	    tty_port_init(&vc->port);
778 	    INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
779 	    visual_init(vc, currcons, 1);
780 	    if (!*vc->vc_uni_pagedir_loc)
781 		con_set_default_unimap(vc);
782 	    vc->vc_screenbuf = kmalloc(vc->vc_screenbuf_size, GFP_KERNEL);
783 	    if (!vc->vc_screenbuf) {
784 		kfree(vc);
785 		vc_cons[currcons].d = NULL;
786 		return -ENOMEM;
787 	    }
788 
789 	    /* If no drivers have overridden us and the user didn't pass a
790 	       boot option, default to displaying the cursor */
791 	    if (global_cursor_default == -1)
792 		    global_cursor_default = 1;
793 
794 	    vc_init(vc, vc->vc_rows, vc->vc_cols, 1);
795 	    vcs_make_sysfs(currcons);
796 	    atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, &param);
797 	}
798 	return 0;
799 }
800 
801 static inline int resize_screen(struct vc_data *vc, int width, int height,
802 				int user)
803 {
804 	/* Resizes the resolution of the display adapater */
805 	int err = 0;
806 
807 	if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_resize)
808 		err = vc->vc_sw->con_resize(vc, width, height, user);
809 
810 	return err;
811 }
812 
813 /*
814  * Change # of rows and columns (0 means unchanged/the size of fg_console)
815  * [this is to be used together with some user program
816  * like resize that changes the hardware videomode]
817  */
818 #define VC_RESIZE_MAXCOL (32767)
819 #define VC_RESIZE_MAXROW (32767)
820 
821 /**
822  *	vc_do_resize	-	resizing method for the tty
823  *	@tty: tty being resized
824  *	@real_tty: real tty (different to tty if a pty/tty pair)
825  *	@vc: virtual console private data
826  *	@cols: columns
827  *	@lines: lines
828  *
829  *	Resize a virtual console, clipping according to the actual constraints.
830  *	If the caller passes a tty structure then update the termios winsize
831  *	information and perform any necessary signal handling.
832  *
833  *	Caller must hold the console semaphore. Takes the termios rwsem and
834  *	ctrl_lock of the tty IFF a tty is passed.
835  */
836 
837 static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
838 				unsigned int cols, unsigned int lines)
839 {
840 	unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
841 	unsigned long end;
842 	unsigned int old_rows, old_row_size;
843 	unsigned int new_cols, new_rows, new_row_size, new_screen_size;
844 	unsigned int user;
845 	unsigned short *newscreen;
846 
847 	WARN_CONSOLE_UNLOCKED();
848 
849 	if (!vc)
850 		return -ENXIO;
851 
852 	user = vc->vc_resize_user;
853 	vc->vc_resize_user = 0;
854 
855 	if (cols > VC_RESIZE_MAXCOL || lines > VC_RESIZE_MAXROW)
856 		return -EINVAL;
857 
858 	new_cols = (cols ? cols : vc->vc_cols);
859 	new_rows = (lines ? lines : vc->vc_rows);
860 	new_row_size = new_cols << 1;
861 	new_screen_size = new_row_size * new_rows;
862 
863 	if (new_cols == vc->vc_cols && new_rows == vc->vc_rows)
864 		return 0;
865 
866 	newscreen = kmalloc(new_screen_size, GFP_USER);
867 	if (!newscreen)
868 		return -ENOMEM;
869 
870 	old_rows = vc->vc_rows;
871 	old_row_size = vc->vc_size_row;
872 
873 	err = resize_screen(vc, new_cols, new_rows, user);
874 	if (err) {
875 		kfree(newscreen);
876 		return err;
877 	}
878 
879 	vc->vc_rows = new_rows;
880 	vc->vc_cols = new_cols;
881 	vc->vc_size_row = new_row_size;
882 	vc->vc_screenbuf_size = new_screen_size;
883 
884 	rlth = min(old_row_size, new_row_size);
885 	rrem = new_row_size - rlth;
886 	old_origin = vc->vc_origin;
887 	new_origin = (long) newscreen;
888 	new_scr_end = new_origin + new_screen_size;
889 
890 	if (vc->vc_y > new_rows) {
891 		if (old_rows - vc->vc_y < new_rows) {
892 			/*
893 			 * Cursor near the bottom, copy contents from the
894 			 * bottom of buffer
895 			 */
896 			old_origin += (old_rows - new_rows) * old_row_size;
897 		} else {
898 			/*
899 			 * Cursor is in no man's land, copy 1/2 screenful
900 			 * from the top and bottom of cursor position
901 			 */
902 			old_origin += (vc->vc_y - new_rows/2) * old_row_size;
903 		}
904 	}
905 
906 	end = old_origin + old_row_size * min(old_rows, new_rows);
907 
908 	update_attr(vc);
909 
910 	while (old_origin < end) {
911 		scr_memcpyw((unsigned short *) new_origin,
912 			    (unsigned short *) old_origin, rlth);
913 		if (rrem)
914 			scr_memsetw((void *)(new_origin + rlth),
915 				    vc->vc_video_erase_char, rrem);
916 		old_origin += old_row_size;
917 		new_origin += new_row_size;
918 	}
919 	if (new_scr_end > new_origin)
920 		scr_memsetw((void *)new_origin, vc->vc_video_erase_char,
921 			    new_scr_end - new_origin);
922 	kfree(vc->vc_screenbuf);
923 	vc->vc_screenbuf = newscreen;
924 	vc->vc_screenbuf_size = new_screen_size;
925 	set_origin(vc);
926 
927 	/* do part of a reset_terminal() */
928 	vc->vc_top = 0;
929 	vc->vc_bottom = vc->vc_rows;
930 	gotoxy(vc, vc->vc_x, vc->vc_y);
931 	save_cur(vc);
932 
933 	if (tty) {
934 		/* Rewrite the requested winsize data with the actual
935 		   resulting sizes */
936 		struct winsize ws;
937 		memset(&ws, 0, sizeof(ws));
938 		ws.ws_row = vc->vc_rows;
939 		ws.ws_col = vc->vc_cols;
940 		ws.ws_ypixel = vc->vc_scan_lines;
941 		tty_do_resize(tty, &ws);
942 	}
943 
944 	if (CON_IS_VISIBLE(vc))
945 		update_screen(vc);
946 	vt_event_post(VT_EVENT_RESIZE, vc->vc_num, vc->vc_num);
947 	return err;
948 }
949 
950 /**
951  *	vc_resize		-	resize a VT
952  *	@vc: virtual console
953  *	@cols: columns
954  *	@rows: rows
955  *
956  *	Resize a virtual console as seen from the console end of things. We
957  *	use the common vc_do_resize methods to update the structures. The
958  *	caller must hold the console sem to protect console internals and
959  *	vc->port.tty
960  */
961 
962 int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
963 {
964 	return vc_do_resize(vc->port.tty, vc, cols, rows);
965 }
966 
967 /**
968  *	vt_resize		-	resize a VT
969  *	@tty: tty to resize
970  *	@ws: winsize attributes
971  *
972  *	Resize a virtual terminal. This is called by the tty layer as we
973  *	register our own handler for resizing. The mutual helper does all
974  *	the actual work.
975  *
976  *	Takes the console sem and the called methods then take the tty
977  *	termios_rwsem and the tty ctrl_lock in that order.
978  */
979 static int vt_resize(struct tty_struct *tty, struct winsize *ws)
980 {
981 	struct vc_data *vc = tty->driver_data;
982 	int ret;
983 
984 	console_lock();
985 	ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row);
986 	console_unlock();
987 	return ret;
988 }
989 
990 struct vc_data *vc_deallocate(unsigned int currcons)
991 {
992 	struct vc_data *vc = NULL;
993 
994 	WARN_CONSOLE_UNLOCKED();
995 
996 	if (vc_cons_allocated(currcons)) {
997 		struct vt_notifier_param param;
998 
999 		param.vc = vc = vc_cons[currcons].d;
1000 		atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, &param);
1001 		vcs_remove_sysfs(currcons);
1002 		vc->vc_sw->con_deinit(vc);
1003 		put_pid(vc->vt_pid);
1004 		module_put(vc->vc_sw->owner);
1005 		kfree(vc->vc_screenbuf);
1006 		vc_cons[currcons].d = NULL;
1007 	}
1008 	return vc;
1009 }
1010 
1011 /*
1012  *	VT102 emulator
1013  */
1014 
1015 #define set_kbd(vc, x)	vt_set_kbd_mode_bit((vc)->vc_num, (x))
1016 #define clr_kbd(vc, x)	vt_clr_kbd_mode_bit((vc)->vc_num, (x))
1017 #define is_kbd(vc, x)	vt_get_kbd_mode_bit((vc)->vc_num, (x))
1018 
1019 #define decarm		VC_REPEAT
1020 #define decckm		VC_CKMODE
1021 #define kbdapplic	VC_APPLIC
1022 #define lnm		VC_CRLF
1023 
1024 /*
1025  * this is what the terminal answers to a ESC-Z or csi0c query.
1026  */
1027 #define VT100ID "\033[?1;2c"
1028 #define VT102ID "\033[?6c"
1029 
1030 unsigned char color_table[] = { 0, 4, 2, 6, 1, 5, 3, 7,
1031 				       8,12,10,14, 9,13,11,15 };
1032 
1033 /* the default colour table, for VGA+ colour systems */
1034 int default_red[] = {0x00,0xaa,0x00,0xaa,0x00,0xaa,0x00,0xaa,
1035     0x55,0xff,0x55,0xff,0x55,0xff,0x55,0xff};
1036 int default_grn[] = {0x00,0x00,0xaa,0x55,0x00,0x00,0xaa,0xaa,
1037     0x55,0x55,0xff,0xff,0x55,0x55,0xff,0xff};
1038 int default_blu[] = {0x00,0x00,0x00,0x00,0xaa,0xaa,0xaa,0xaa,
1039     0x55,0x55,0x55,0x55,0xff,0xff,0xff,0xff};
1040 
1041 module_param_array(default_red, int, NULL, S_IRUGO | S_IWUSR);
1042 module_param_array(default_grn, int, NULL, S_IRUGO | S_IWUSR);
1043 module_param_array(default_blu, int, NULL, S_IRUGO | S_IWUSR);
1044 
1045 /*
1046  * gotoxy() must verify all boundaries, because the arguments
1047  * might also be negative. If the given position is out of
1048  * bounds, the cursor is placed at the nearest margin.
1049  */
1050 static void gotoxy(struct vc_data *vc, int new_x, int new_y)
1051 {
1052 	int min_y, max_y;
1053 
1054 	if (new_x < 0)
1055 		vc->vc_x = 0;
1056 	else {
1057 		if (new_x >= vc->vc_cols)
1058 			vc->vc_x = vc->vc_cols - 1;
1059 		else
1060 			vc->vc_x = new_x;
1061 	}
1062 
1063  	if (vc->vc_decom) {
1064 		min_y = vc->vc_top;
1065 		max_y = vc->vc_bottom;
1066 	} else {
1067 		min_y = 0;
1068 		max_y = vc->vc_rows;
1069 	}
1070 	if (new_y < min_y)
1071 		vc->vc_y = min_y;
1072 	else if (new_y >= max_y)
1073 		vc->vc_y = max_y - 1;
1074 	else
1075 		vc->vc_y = new_y;
1076 	vc->vc_pos = vc->vc_origin + vc->vc_y * vc->vc_size_row + (vc->vc_x<<1);
1077 	vc->vc_need_wrap = 0;
1078 }
1079 
1080 /* for absolute user moves, when decom is set */
1081 static void gotoxay(struct vc_data *vc, int new_x, int new_y)
1082 {
1083 	gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y);
1084 }
1085 
1086 void scrollback(struct vc_data *vc, int lines)
1087 {
1088 	if (!lines)
1089 		lines = vc->vc_rows / 2;
1090 	scrolldelta(-lines);
1091 }
1092 
1093 void scrollfront(struct vc_data *vc, int lines)
1094 {
1095 	if (!lines)
1096 		lines = vc->vc_rows / 2;
1097 	scrolldelta(lines);
1098 }
1099 
1100 static void lf(struct vc_data *vc)
1101 {
1102     	/* don't scroll if above bottom of scrolling region, or
1103 	 * if below scrolling region
1104 	 */
1105     	if (vc->vc_y + 1 == vc->vc_bottom)
1106 		scrup(vc, vc->vc_top, vc->vc_bottom, 1);
1107 	else if (vc->vc_y < vc->vc_rows - 1) {
1108 	    	vc->vc_y++;
1109 		vc->vc_pos += vc->vc_size_row;
1110 	}
1111 	vc->vc_need_wrap = 0;
1112 	notify_write(vc, '\n');
1113 }
1114 
1115 static void ri(struct vc_data *vc)
1116 {
1117     	/* don't scroll if below top of scrolling region, or
1118 	 * if above scrolling region
1119 	 */
1120 	if (vc->vc_y == vc->vc_top)
1121 		scrdown(vc, vc->vc_top, vc->vc_bottom, 1);
1122 	else if (vc->vc_y > 0) {
1123 		vc->vc_y--;
1124 		vc->vc_pos -= vc->vc_size_row;
1125 	}
1126 	vc->vc_need_wrap = 0;
1127 }
1128 
1129 static inline void cr(struct vc_data *vc)
1130 {
1131 	vc->vc_pos -= vc->vc_x << 1;
1132 	vc->vc_need_wrap = vc->vc_x = 0;
1133 	notify_write(vc, '\r');
1134 }
1135 
1136 static inline void bs(struct vc_data *vc)
1137 {
1138 	if (vc->vc_x) {
1139 		vc->vc_pos -= 2;
1140 		vc->vc_x--;
1141 		vc->vc_need_wrap = 0;
1142 		notify_write(vc, '\b');
1143 	}
1144 }
1145 
1146 static inline void del(struct vc_data *vc)
1147 {
1148 	/* ignored */
1149 }
1150 
1151 static void csi_J(struct vc_data *vc, int vpar)
1152 {
1153 	unsigned int count;
1154 	unsigned short * start;
1155 
1156 	switch (vpar) {
1157 		case 0:	/* erase from cursor to end of display */
1158 			count = (vc->vc_scr_end - vc->vc_pos) >> 1;
1159 			start = (unsigned short *)vc->vc_pos;
1160 			break;
1161 		case 1:	/* erase from start to cursor */
1162 			count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1;
1163 			start = (unsigned short *)vc->vc_origin;
1164 			break;
1165 		case 3: /* erase scroll-back buffer (and whole display) */
1166 			scr_memsetw(vc->vc_screenbuf, vc->vc_video_erase_char,
1167 				    vc->vc_screenbuf_size >> 1);
1168 			set_origin(vc);
1169 			if (CON_IS_VISIBLE(vc))
1170 				update_screen(vc);
1171 			/* fall through */
1172 		case 2: /* erase whole display */
1173 			count = vc->vc_cols * vc->vc_rows;
1174 			start = (unsigned short *)vc->vc_origin;
1175 			break;
1176 		default:
1177 			return;
1178 	}
1179 	scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1180 	if (DO_UPDATE(vc))
1181 		do_update_region(vc, (unsigned long) start, count);
1182 	vc->vc_need_wrap = 0;
1183 }
1184 
1185 static void csi_K(struct vc_data *vc, int vpar)
1186 {
1187 	unsigned int count;
1188 	unsigned short * start;
1189 
1190 	switch (vpar) {
1191 		case 0:	/* erase from cursor to end of line */
1192 			count = vc->vc_cols - vc->vc_x;
1193 			start = (unsigned short *)vc->vc_pos;
1194 			break;
1195 		case 1:	/* erase from start of line to cursor */
1196 			start = (unsigned short *)(vc->vc_pos - (vc->vc_x << 1));
1197 			count = vc->vc_x + 1;
1198 			break;
1199 		case 2: /* erase whole line */
1200 			start = (unsigned short *)(vc->vc_pos - (vc->vc_x << 1));
1201 			count = vc->vc_cols;
1202 			break;
1203 		default:
1204 			return;
1205 	}
1206 	scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1207 	vc->vc_need_wrap = 0;
1208 	if (DO_UPDATE(vc))
1209 		do_update_region(vc, (unsigned long) start, count);
1210 }
1211 
1212 static void csi_X(struct vc_data *vc, int vpar) /* erase the following vpar positions */
1213 {					  /* not vt100? */
1214 	int count;
1215 
1216 	if (!vpar)
1217 		vpar++;
1218 	count = (vpar > vc->vc_cols - vc->vc_x) ? (vc->vc_cols - vc->vc_x) : vpar;
1219 
1220 	scr_memsetw((unsigned short *)vc->vc_pos, vc->vc_video_erase_char, 2 * count);
1221 	if (DO_UPDATE(vc))
1222 		vc->vc_sw->con_clear(vc, vc->vc_y, vc->vc_x, 1, count);
1223 	vc->vc_need_wrap = 0;
1224 }
1225 
1226 static void default_attr(struct vc_data *vc)
1227 {
1228 	vc->vc_intensity = 1;
1229 	vc->vc_italic = 0;
1230 	vc->vc_underline = 0;
1231 	vc->vc_reverse = 0;
1232 	vc->vc_blink = 0;
1233 	vc->vc_color = vc->vc_def_color;
1234 }
1235 
1236 struct rgb { u8 r; u8 g; u8 b; };
1237 
1238 struct rgb rgb_from_256(int i)
1239 {
1240 	struct rgb c;
1241 	if (i < 8) {            /* Standard colours. */
1242 		c.r = i&1 ? 0xaa : 0x00;
1243 		c.g = i&2 ? 0xaa : 0x00;
1244 		c.b = i&4 ? 0xaa : 0x00;
1245 	} else if (i < 16) {
1246 		c.r = i&1 ? 0xff : 0x55;
1247 		c.g = i&2 ? 0xff : 0x55;
1248 		c.b = i&4 ? 0xff : 0x55;
1249 	} else if (i < 232) {   /* 6x6x6 colour cube. */
1250 		c.r = (i - 16) / 36 * 85 / 2;
1251 		c.g = (i - 16) / 6 % 6 * 85 / 2;
1252 		c.b = (i - 16) % 6 * 85 / 2;
1253 	} else                  /* Grayscale ramp. */
1254 		c.r = c.g = c.b = i * 10 - 2312;
1255 	return c;
1256 }
1257 
1258 static void rgb_foreground(struct vc_data *vc, struct rgb c)
1259 {
1260 	u8 hue, max = c.r;
1261 	if (c.g > max)
1262 		max = c.g;
1263 	if (c.b > max)
1264 		max = c.b;
1265 	hue = (c.r > max/2 ? 4 : 0)
1266 	    | (c.g > max/2 ? 2 : 0)
1267 	    | (c.b > max/2 ? 1 : 0);
1268 	if (hue == 7 && max <= 0x55)
1269 		hue = 0, vc->vc_intensity = 2;
1270 	else
1271 		vc->vc_intensity = (max > 0xaa) + 1;
1272 	vc->vc_color = (vc->vc_color & 0xf0) | hue;
1273 }
1274 
1275 static void rgb_background(struct vc_data *vc, struct rgb c)
1276 {
1277 	/* For backgrounds, err on the dark side. */
1278 	vc->vc_color = (vc->vc_color & 0x0f)
1279 		| (c.r&0x80) >> 1 | (c.g&0x80) >> 2 | (c.b&0x80) >> 3;
1280 }
1281 
1282 /* console_lock is held */
1283 static void csi_m(struct vc_data *vc)
1284 {
1285 	int i;
1286 
1287 	for (i = 0; i <= vc->vc_npar; i++)
1288 		switch (vc->vc_par[i]) {
1289 			case 0:	/* all attributes off */
1290 				default_attr(vc);
1291 				break;
1292 			case 1:
1293 				vc->vc_intensity = 2;
1294 				break;
1295 			case 2:
1296 				vc->vc_intensity = 0;
1297 				break;
1298 			case 3:
1299 				vc->vc_italic = 1;
1300 				break;
1301 			case 4:
1302 				vc->vc_underline = 1;
1303 				break;
1304 			case 5:
1305 				vc->vc_blink = 1;
1306 				break;
1307 			case 7:
1308 				vc->vc_reverse = 1;
1309 				break;
1310 			case 10: /* ANSI X3.64-1979 (SCO-ish?)
1311 				  * Select primary font, don't display
1312 				  * control chars if defined, don't set
1313 				  * bit 8 on output.
1314 				  */
1315 				vc->vc_translate = set_translate(vc->vc_charset == 0
1316 						? vc->vc_G0_charset
1317 						: vc->vc_G1_charset, vc);
1318 				vc->vc_disp_ctrl = 0;
1319 				vc->vc_toggle_meta = 0;
1320 				break;
1321 			case 11: /* ANSI X3.64-1979 (SCO-ish?)
1322 				  * Select first alternate font, lets
1323 				  * chars < 32 be displayed as ROM chars.
1324 				  */
1325 				vc->vc_translate = set_translate(IBMPC_MAP, vc);
1326 				vc->vc_disp_ctrl = 1;
1327 				vc->vc_toggle_meta = 0;
1328 				break;
1329 			case 12: /* ANSI X3.64-1979 (SCO-ish?)
1330 				  * Select second alternate font, toggle
1331 				  * high bit before displaying as ROM char.
1332 				  */
1333 				vc->vc_translate = set_translate(IBMPC_MAP, vc);
1334 				vc->vc_disp_ctrl = 1;
1335 				vc->vc_toggle_meta = 1;
1336 				break;
1337 			case 21:
1338 			case 22:
1339 				vc->vc_intensity = 1;
1340 				break;
1341 			case 23:
1342 				vc->vc_italic = 0;
1343 				break;
1344 			case 24:
1345 				vc->vc_underline = 0;
1346 				break;
1347 			case 25:
1348 				vc->vc_blink = 0;
1349 				break;
1350 			case 27:
1351 				vc->vc_reverse = 0;
1352 				break;
1353 			case 38: /* ITU T.416
1354 				  * Higher colour modes.
1355 				  * They break the usual properties of SGR codes
1356 				  * and thus need to be detected and ignored by
1357 				  * hand.  Strictly speaking, that standard also
1358 				  * wants : rather than ; as separators, contrary
1359 				  * to ECMA-48, but no one produces such codes
1360 				  * and almost no one accepts them.
1361 				  */
1362 				i++;
1363 				if (i > vc->vc_npar)
1364 					break;
1365 				if (vc->vc_par[i] == 5 &&  /* 256 colours */
1366 				    i < vc->vc_npar) {     /* ubiquitous */
1367 					i++;
1368 					rgb_foreground(vc,
1369 						rgb_from_256(vc->vc_par[i]));
1370 				} else if (vc->vc_par[i] == 2 &&  /* 24 bit */
1371 				           i <= vc->vc_npar + 3) {/* extremely rare */
1372 					struct rgb c = {
1373 						.r = vc->vc_par[i + 1],
1374 						.g = vc->vc_par[i + 2],
1375 						.b = vc->vc_par[i + 3],
1376 					};
1377 					rgb_foreground(vc, c);
1378 					i += 3;
1379 				}
1380 				/* Subcommands 3 (CMY) and 4 (CMYK) are so insane
1381 				 * there's no point in supporting them.
1382 				 */
1383 				break;
1384 			case 48:
1385 				i++;
1386 				if (i > vc->vc_npar)
1387 					break;
1388 				if (vc->vc_par[i] == 5 &&  /* 256 colours */
1389 				    i < vc->vc_npar) {
1390 					i++;
1391 					rgb_background(vc,
1392 						rgb_from_256(vc->vc_par[i]));
1393 				} else if (vc->vc_par[i] == 2 && /* 24 bit */
1394 				           i <= vc->vc_npar + 3) {
1395 					struct rgb c = {
1396 						.r = vc->vc_par[i + 1],
1397 						.g = vc->vc_par[i + 2],
1398 						.b = vc->vc_par[i + 3],
1399 					};
1400 					rgb_background(vc, c);
1401 					i += 3;
1402 				}
1403 				break;
1404 			case 39:
1405 				vc->vc_color = (vc->vc_def_color & 0x0f) | (vc->vc_color & 0xf0);
1406 				break;
1407 			case 49:
1408 				vc->vc_color = (vc->vc_def_color & 0xf0) | (vc->vc_color & 0x0f);
1409 				break;
1410 			default:
1411 				if (vc->vc_par[i] >= 30 && vc->vc_par[i] <= 37)
1412 					vc->vc_color = color_table[vc->vc_par[i] - 30]
1413 						| (vc->vc_color & 0xf0);
1414 				else if (vc->vc_par[i] >= 40 && vc->vc_par[i] <= 47)
1415 					vc->vc_color = (color_table[vc->vc_par[i] - 40] << 4)
1416 						| (vc->vc_color & 0x0f);
1417 				break;
1418 		}
1419 	update_attr(vc);
1420 }
1421 
1422 static void respond_string(const char *p, struct tty_port *port)
1423 {
1424 	while (*p) {
1425 		tty_insert_flip_char(port, *p, 0);
1426 		p++;
1427 	}
1428 	tty_schedule_flip(port);
1429 }
1430 
1431 static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
1432 {
1433 	char buf[40];
1434 
1435 	sprintf(buf, "\033[%d;%dR", vc->vc_y + (vc->vc_decom ? vc->vc_top + 1 : 1), vc->vc_x + 1);
1436 	respond_string(buf, tty->port);
1437 }
1438 
1439 static inline void status_report(struct tty_struct *tty)
1440 {
1441 	respond_string("\033[0n", tty->port);	/* Terminal ok */
1442 }
1443 
1444 static inline void respond_ID(struct tty_struct *tty)
1445 {
1446 	respond_string(VT102ID, tty->port);
1447 }
1448 
1449 void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
1450 {
1451 	char buf[8];
1452 
1453 	sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt), (char)('!' + mrx),
1454 		(char)('!' + mry));
1455 	respond_string(buf, tty->port);
1456 }
1457 
1458 /* invoked via ioctl(TIOCLINUX) and through set_selection */
1459 int mouse_reporting(void)
1460 {
1461 	return vc_cons[fg_console].d->vc_report_mouse;
1462 }
1463 
1464 /* console_lock is held */
1465 static void set_mode(struct vc_data *vc, int on_off)
1466 {
1467 	int i;
1468 
1469 	for (i = 0; i <= vc->vc_npar; i++)
1470 		if (vc->vc_ques) {
1471 			switch(vc->vc_par[i]) {	/* DEC private modes set/reset */
1472 			case 1:			/* Cursor keys send ^[Ox/^[[x */
1473 				if (on_off)
1474 					set_kbd(vc, decckm);
1475 				else
1476 					clr_kbd(vc, decckm);
1477 				break;
1478 			case 3:	/* 80/132 mode switch unimplemented */
1479 				vc->vc_deccolm = on_off;
1480 #if 0
1481 				vc_resize(deccolm ? 132 : 80, vc->vc_rows);
1482 				/* this alone does not suffice; some user mode
1483 				   utility has to change the hardware regs */
1484 #endif
1485 				break;
1486 			case 5:			/* Inverted screen on/off */
1487 				if (vc->vc_decscnm != on_off) {
1488 					vc->vc_decscnm = on_off;
1489 					invert_screen(vc, 0, vc->vc_screenbuf_size, 0);
1490 					update_attr(vc);
1491 				}
1492 				break;
1493 			case 6:			/* Origin relative/absolute */
1494 				vc->vc_decom = on_off;
1495 				gotoxay(vc, 0, 0);
1496 				break;
1497 			case 7:			/* Autowrap on/off */
1498 				vc->vc_decawm = on_off;
1499 				break;
1500 			case 8:			/* Autorepeat on/off */
1501 				if (on_off)
1502 					set_kbd(vc, decarm);
1503 				else
1504 					clr_kbd(vc, decarm);
1505 				break;
1506 			case 9:
1507 				vc->vc_report_mouse = on_off ? 1 : 0;
1508 				break;
1509 			case 25:		/* Cursor on/off */
1510 				vc->vc_deccm = on_off;
1511 				break;
1512 			case 1000:
1513 				vc->vc_report_mouse = on_off ? 2 : 0;
1514 				break;
1515 			}
1516 		} else {
1517 			switch(vc->vc_par[i]) {	/* ANSI modes set/reset */
1518 			case 3:			/* Monitor (display ctrls) */
1519 				vc->vc_disp_ctrl = on_off;
1520 				break;
1521 			case 4:			/* Insert Mode on/off */
1522 				vc->vc_decim = on_off;
1523 				break;
1524 			case 20:		/* Lf, Enter == CrLf/Lf */
1525 				if (on_off)
1526 					set_kbd(vc, lnm);
1527 				else
1528 					clr_kbd(vc, lnm);
1529 				break;
1530 			}
1531 		}
1532 }
1533 
1534 /* console_lock is held */
1535 static void setterm_command(struct vc_data *vc)
1536 {
1537 	switch(vc->vc_par[0]) {
1538 		case 1:	/* set color for underline mode */
1539 			if (vc->vc_can_do_color &&
1540 					vc->vc_par[1] < 16) {
1541 				vc->vc_ulcolor = color_table[vc->vc_par[1]];
1542 				if (vc->vc_underline)
1543 					update_attr(vc);
1544 			}
1545 			break;
1546 		case 2:	/* set color for half intensity mode */
1547 			if (vc->vc_can_do_color &&
1548 					vc->vc_par[1] < 16) {
1549 				vc->vc_halfcolor = color_table[vc->vc_par[1]];
1550 				if (vc->vc_intensity == 0)
1551 					update_attr(vc);
1552 			}
1553 			break;
1554 		case 8:	/* store colors as defaults */
1555 			vc->vc_def_color = vc->vc_attr;
1556 			if (vc->vc_hi_font_mask == 0x100)
1557 				vc->vc_def_color >>= 1;
1558 			default_attr(vc);
1559 			update_attr(vc);
1560 			break;
1561 		case 9:	/* set blanking interval */
1562 			blankinterval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60;
1563 			poke_blanked_console();
1564 			break;
1565 		case 10: /* set bell frequency in Hz */
1566 			if (vc->vc_npar >= 1)
1567 				vc->vc_bell_pitch = vc->vc_par[1];
1568 			else
1569 				vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
1570 			break;
1571 		case 11: /* set bell duration in msec */
1572 			if (vc->vc_npar >= 1)
1573 				vc->vc_bell_duration = (vc->vc_par[1] < 2000) ?
1574 					vc->vc_par[1] * HZ / 1000 : 0;
1575 			else
1576 				vc->vc_bell_duration = DEFAULT_BELL_DURATION;
1577 			break;
1578 		case 12: /* bring specified console to the front */
1579 			if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1))
1580 				set_console(vc->vc_par[1] - 1);
1581 			break;
1582 		case 13: /* unblank the screen */
1583 			poke_blanked_console();
1584 			break;
1585 		case 14: /* set vesa powerdown interval */
1586 			vesa_off_interval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60 * HZ;
1587 			break;
1588 		case 15: /* activate the previous console */
1589 			set_console(last_console);
1590 			break;
1591 	}
1592 }
1593 
1594 /* console_lock is held */
1595 static void csi_at(struct vc_data *vc, unsigned int nr)
1596 {
1597 	if (nr > vc->vc_cols - vc->vc_x)
1598 		nr = vc->vc_cols - vc->vc_x;
1599 	else if (!nr)
1600 		nr = 1;
1601 	insert_char(vc, nr);
1602 }
1603 
1604 /* console_lock is held */
1605 static void csi_L(struct vc_data *vc, unsigned int nr)
1606 {
1607 	if (nr > vc->vc_rows - vc->vc_y)
1608 		nr = vc->vc_rows - vc->vc_y;
1609 	else if (!nr)
1610 		nr = 1;
1611 	scrdown(vc, vc->vc_y, vc->vc_bottom, nr);
1612 	vc->vc_need_wrap = 0;
1613 }
1614 
1615 /* console_lock is held */
1616 static void csi_P(struct vc_data *vc, unsigned int nr)
1617 {
1618 	if (nr > vc->vc_cols - vc->vc_x)
1619 		nr = vc->vc_cols - vc->vc_x;
1620 	else if (!nr)
1621 		nr = 1;
1622 	delete_char(vc, nr);
1623 }
1624 
1625 /* console_lock is held */
1626 static void csi_M(struct vc_data *vc, unsigned int nr)
1627 {
1628 	if (nr > vc->vc_rows - vc->vc_y)
1629 		nr = vc->vc_rows - vc->vc_y;
1630 	else if (!nr)
1631 		nr=1;
1632 	scrup(vc, vc->vc_y, vc->vc_bottom, nr);
1633 	vc->vc_need_wrap = 0;
1634 }
1635 
1636 /* console_lock is held (except via vc_init->reset_terminal */
1637 static void save_cur(struct vc_data *vc)
1638 {
1639 	vc->vc_saved_x		= vc->vc_x;
1640 	vc->vc_saved_y		= vc->vc_y;
1641 	vc->vc_s_intensity	= vc->vc_intensity;
1642 	vc->vc_s_italic         = vc->vc_italic;
1643 	vc->vc_s_underline	= vc->vc_underline;
1644 	vc->vc_s_blink		= vc->vc_blink;
1645 	vc->vc_s_reverse	= vc->vc_reverse;
1646 	vc->vc_s_charset	= vc->vc_charset;
1647 	vc->vc_s_color		= vc->vc_color;
1648 	vc->vc_saved_G0		= vc->vc_G0_charset;
1649 	vc->vc_saved_G1		= vc->vc_G1_charset;
1650 }
1651 
1652 /* console_lock is held */
1653 static void restore_cur(struct vc_data *vc)
1654 {
1655 	gotoxy(vc, vc->vc_saved_x, vc->vc_saved_y);
1656 	vc->vc_intensity	= vc->vc_s_intensity;
1657 	vc->vc_italic		= vc->vc_s_italic;
1658 	vc->vc_underline	= vc->vc_s_underline;
1659 	vc->vc_blink		= vc->vc_s_blink;
1660 	vc->vc_reverse		= vc->vc_s_reverse;
1661 	vc->vc_charset		= vc->vc_s_charset;
1662 	vc->vc_color		= vc->vc_s_color;
1663 	vc->vc_G0_charset	= vc->vc_saved_G0;
1664 	vc->vc_G1_charset	= vc->vc_saved_G1;
1665 	vc->vc_translate	= set_translate(vc->vc_charset ? vc->vc_G1_charset : vc->vc_G0_charset, vc);
1666 	update_attr(vc);
1667 	vc->vc_need_wrap = 0;
1668 }
1669 
1670 enum { ESnormal, ESesc, ESsquare, ESgetpars, ESfunckey,
1671 	EShash, ESsetG0, ESsetG1, ESpercent, ESignore, ESnonstd,
1672 	ESpalette, ESosc };
1673 
1674 /* console_lock is held (except via vc_init()) */
1675 static void reset_terminal(struct vc_data *vc, int do_clear)
1676 {
1677 	vc->vc_top		= 0;
1678 	vc->vc_bottom		= vc->vc_rows;
1679 	vc->vc_state		= ESnormal;
1680 	vc->vc_ques		= 0;
1681 	vc->vc_translate	= set_translate(LAT1_MAP, vc);
1682 	vc->vc_G0_charset	= LAT1_MAP;
1683 	vc->vc_G1_charset	= GRAF_MAP;
1684 	vc->vc_charset		= 0;
1685 	vc->vc_need_wrap	= 0;
1686 	vc->vc_report_mouse	= 0;
1687 	vc->vc_utf              = default_utf8;
1688 	vc->vc_utf_count	= 0;
1689 
1690 	vc->vc_disp_ctrl	= 0;
1691 	vc->vc_toggle_meta	= 0;
1692 
1693 	vc->vc_decscnm		= 0;
1694 	vc->vc_decom		= 0;
1695 	vc->vc_decawm		= 1;
1696 	vc->vc_deccm		= global_cursor_default;
1697 	vc->vc_decim		= 0;
1698 
1699 	vt_reset_keyboard(vc->vc_num);
1700 
1701 	vc->vc_cursor_type = cur_default;
1702 	vc->vc_complement_mask = vc->vc_s_complement_mask;
1703 
1704 	default_attr(vc);
1705 	update_attr(vc);
1706 
1707 	vc->vc_tab_stop[0]	= 0x01010100;
1708 	vc->vc_tab_stop[1]	=
1709 	vc->vc_tab_stop[2]	=
1710 	vc->vc_tab_stop[3]	=
1711 	vc->vc_tab_stop[4]	=
1712 	vc->vc_tab_stop[5]	=
1713 	vc->vc_tab_stop[6]	=
1714 	vc->vc_tab_stop[7]	= 0x01010101;
1715 
1716 	vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
1717 	vc->vc_bell_duration = DEFAULT_BELL_DURATION;
1718 
1719 	gotoxy(vc, 0, 0);
1720 	save_cur(vc);
1721 	if (do_clear)
1722 	    csi_J(vc, 2);
1723 }
1724 
1725 /* console_lock is held */
1726 static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
1727 {
1728 	/*
1729 	 *  Control characters can be used in the _middle_
1730 	 *  of an escape sequence.
1731 	 */
1732 	if (vc->vc_state == ESosc && c>=8 && c<=13) /* ... except for OSC */
1733 		return;
1734 	switch (c) {
1735 	case 0:
1736 		return;
1737 	case 7:
1738 		if (vc->vc_state == ESosc)
1739 			vc->vc_state = ESnormal;
1740 		else if (vc->vc_bell_duration)
1741 			kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration);
1742 		return;
1743 	case 8:
1744 		bs(vc);
1745 		return;
1746 	case 9:
1747 		vc->vc_pos -= (vc->vc_x << 1);
1748 		while (vc->vc_x < vc->vc_cols - 1) {
1749 			vc->vc_x++;
1750 			if (vc->vc_tab_stop[vc->vc_x >> 5] & (1 << (vc->vc_x & 31)))
1751 				break;
1752 		}
1753 		vc->vc_pos += (vc->vc_x << 1);
1754 		notify_write(vc, '\t');
1755 		return;
1756 	case 10: case 11: case 12:
1757 		lf(vc);
1758 		if (!is_kbd(vc, lnm))
1759 			return;
1760 	case 13:
1761 		cr(vc);
1762 		return;
1763 	case 14:
1764 		vc->vc_charset = 1;
1765 		vc->vc_translate = set_translate(vc->vc_G1_charset, vc);
1766 		vc->vc_disp_ctrl = 1;
1767 		return;
1768 	case 15:
1769 		vc->vc_charset = 0;
1770 		vc->vc_translate = set_translate(vc->vc_G0_charset, vc);
1771 		vc->vc_disp_ctrl = 0;
1772 		return;
1773 	case 24: case 26:
1774 		vc->vc_state = ESnormal;
1775 		return;
1776 	case 27:
1777 		vc->vc_state = ESesc;
1778 		return;
1779 	case 127:
1780 		del(vc);
1781 		return;
1782 	case 128+27:
1783 		vc->vc_state = ESsquare;
1784 		return;
1785 	}
1786 	switch(vc->vc_state) {
1787 	case ESesc:
1788 		vc->vc_state = ESnormal;
1789 		switch (c) {
1790 		case '[':
1791 			vc->vc_state = ESsquare;
1792 			return;
1793 		case ']':
1794 			vc->vc_state = ESnonstd;
1795 			return;
1796 		case '%':
1797 			vc->vc_state = ESpercent;
1798 			return;
1799 		case 'E':
1800 			cr(vc);
1801 			lf(vc);
1802 			return;
1803 		case 'M':
1804 			ri(vc);
1805 			return;
1806 		case 'D':
1807 			lf(vc);
1808 			return;
1809 		case 'H':
1810 			vc->vc_tab_stop[vc->vc_x >> 5] |= (1 << (vc->vc_x & 31));
1811 			return;
1812 		case 'Z':
1813 			respond_ID(tty);
1814 			return;
1815 		case '7':
1816 			save_cur(vc);
1817 			return;
1818 		case '8':
1819 			restore_cur(vc);
1820 			return;
1821 		case '(':
1822 			vc->vc_state = ESsetG0;
1823 			return;
1824 		case ')':
1825 			vc->vc_state = ESsetG1;
1826 			return;
1827 		case '#':
1828 			vc->vc_state = EShash;
1829 			return;
1830 		case 'c':
1831 			reset_terminal(vc, 1);
1832 			return;
1833 		case '>':  /* Numeric keypad */
1834 			clr_kbd(vc, kbdapplic);
1835 			return;
1836 		case '=':  /* Appl. keypad */
1837 			set_kbd(vc, kbdapplic);
1838 			return;
1839 		}
1840 		return;
1841 	case ESnonstd:
1842 		if (c=='P') {   /* palette escape sequence */
1843 			for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
1844 				vc->vc_par[vc->vc_npar] = 0;
1845 			vc->vc_npar = 0;
1846 			vc->vc_state = ESpalette;
1847 			return;
1848 		} else if (c=='R') {   /* reset palette */
1849 			reset_palette(vc);
1850 			vc->vc_state = ESnormal;
1851 		} else if (c>='0' && c<='9')
1852 			vc->vc_state = ESosc;
1853 		else
1854 			vc->vc_state = ESnormal;
1855 		return;
1856 	case ESpalette:
1857 		if (isxdigit(c)) {
1858 			vc->vc_par[vc->vc_npar++] = hex_to_bin(c);
1859 			if (vc->vc_npar == 7) {
1860 				int i = vc->vc_par[0] * 3, j = 1;
1861 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
1862 				vc->vc_palette[i++] += vc->vc_par[j++];
1863 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
1864 				vc->vc_palette[i++] += vc->vc_par[j++];
1865 				vc->vc_palette[i] = 16 * vc->vc_par[j++];
1866 				vc->vc_palette[i] += vc->vc_par[j];
1867 				set_palette(vc);
1868 				vc->vc_state = ESnormal;
1869 			}
1870 		} else
1871 			vc->vc_state = ESnormal;
1872 		return;
1873 	case ESsquare:
1874 		for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
1875 			vc->vc_par[vc->vc_npar] = 0;
1876 		vc->vc_npar = 0;
1877 		vc->vc_state = ESgetpars;
1878 		if (c == '[') { /* Function key */
1879 			vc->vc_state=ESfunckey;
1880 			return;
1881 		}
1882 		vc->vc_ques = (c == '?');
1883 		if (vc->vc_ques)
1884 			return;
1885 	case ESgetpars:
1886 		if (c == ';' && vc->vc_npar < NPAR - 1) {
1887 			vc->vc_npar++;
1888 			return;
1889 		} else if (c>='0' && c<='9') {
1890 			vc->vc_par[vc->vc_npar] *= 10;
1891 			vc->vc_par[vc->vc_npar] += c - '0';
1892 			return;
1893 		}
1894 		vc->vc_state = ESnormal;
1895 		switch(c) {
1896 		case 'h':
1897 			set_mode(vc, 1);
1898 			return;
1899 		case 'l':
1900 			set_mode(vc, 0);
1901 			return;
1902 		case 'c':
1903 			if (vc->vc_ques) {
1904 				if (vc->vc_par[0])
1905 					vc->vc_cursor_type = vc->vc_par[0] | (vc->vc_par[1] << 8) | (vc->vc_par[2] << 16);
1906 				else
1907 					vc->vc_cursor_type = cur_default;
1908 				return;
1909 			}
1910 			break;
1911 		case 'm':
1912 			if (vc->vc_ques) {
1913 				clear_selection();
1914 				if (vc->vc_par[0])
1915 					vc->vc_complement_mask = vc->vc_par[0] << 8 | vc->vc_par[1];
1916 				else
1917 					vc->vc_complement_mask = vc->vc_s_complement_mask;
1918 				return;
1919 			}
1920 			break;
1921 		case 'n':
1922 			if (!vc->vc_ques) {
1923 				if (vc->vc_par[0] == 5)
1924 					status_report(tty);
1925 				else if (vc->vc_par[0] == 6)
1926 					cursor_report(vc, tty);
1927 			}
1928 			return;
1929 		}
1930 		if (vc->vc_ques) {
1931 			vc->vc_ques = 0;
1932 			return;
1933 		}
1934 		switch(c) {
1935 		case 'G': case '`':
1936 			if (vc->vc_par[0])
1937 				vc->vc_par[0]--;
1938 			gotoxy(vc, vc->vc_par[0], vc->vc_y);
1939 			return;
1940 		case 'A':
1941 			if (!vc->vc_par[0])
1942 				vc->vc_par[0]++;
1943 			gotoxy(vc, vc->vc_x, vc->vc_y - vc->vc_par[0]);
1944 			return;
1945 		case 'B': case 'e':
1946 			if (!vc->vc_par[0])
1947 				vc->vc_par[0]++;
1948 			gotoxy(vc, vc->vc_x, vc->vc_y + vc->vc_par[0]);
1949 			return;
1950 		case 'C': case 'a':
1951 			if (!vc->vc_par[0])
1952 				vc->vc_par[0]++;
1953 			gotoxy(vc, vc->vc_x + vc->vc_par[0], vc->vc_y);
1954 			return;
1955 		case 'D':
1956 			if (!vc->vc_par[0])
1957 				vc->vc_par[0]++;
1958 			gotoxy(vc, vc->vc_x - vc->vc_par[0], vc->vc_y);
1959 			return;
1960 		case 'E':
1961 			if (!vc->vc_par[0])
1962 				vc->vc_par[0]++;
1963 			gotoxy(vc, 0, vc->vc_y + vc->vc_par[0]);
1964 			return;
1965 		case 'F':
1966 			if (!vc->vc_par[0])
1967 				vc->vc_par[0]++;
1968 			gotoxy(vc, 0, vc->vc_y - vc->vc_par[0]);
1969 			return;
1970 		case 'd':
1971 			if (vc->vc_par[0])
1972 				vc->vc_par[0]--;
1973 			gotoxay(vc, vc->vc_x ,vc->vc_par[0]);
1974 			return;
1975 		case 'H': case 'f':
1976 			if (vc->vc_par[0])
1977 				vc->vc_par[0]--;
1978 			if (vc->vc_par[1])
1979 				vc->vc_par[1]--;
1980 			gotoxay(vc, vc->vc_par[1], vc->vc_par[0]);
1981 			return;
1982 		case 'J':
1983 			csi_J(vc, vc->vc_par[0]);
1984 			return;
1985 		case 'K':
1986 			csi_K(vc, vc->vc_par[0]);
1987 			return;
1988 		case 'L':
1989 			csi_L(vc, vc->vc_par[0]);
1990 			return;
1991 		case 'M':
1992 			csi_M(vc, vc->vc_par[0]);
1993 			return;
1994 		case 'P':
1995 			csi_P(vc, vc->vc_par[0]);
1996 			return;
1997 		case 'c':
1998 			if (!vc->vc_par[0])
1999 				respond_ID(tty);
2000 			return;
2001 		case 'g':
2002 			if (!vc->vc_par[0])
2003 				vc->vc_tab_stop[vc->vc_x >> 5] &= ~(1 << (vc->vc_x & 31));
2004 			else if (vc->vc_par[0] == 3) {
2005 				vc->vc_tab_stop[0] =
2006 					vc->vc_tab_stop[1] =
2007 					vc->vc_tab_stop[2] =
2008 					vc->vc_tab_stop[3] =
2009 					vc->vc_tab_stop[4] =
2010 					vc->vc_tab_stop[5] =
2011 					vc->vc_tab_stop[6] =
2012 					vc->vc_tab_stop[7] = 0;
2013 			}
2014 			return;
2015 		case 'm':
2016 			csi_m(vc);
2017 			return;
2018 		case 'q': /* DECLL - but only 3 leds */
2019 			/* map 0,1,2,3 to 0,1,2,4 */
2020 			if (vc->vc_par[0] < 4)
2021 				vt_set_led_state(vc->vc_num,
2022 					    (vc->vc_par[0] < 3) ? vc->vc_par[0] : 4);
2023 			return;
2024 		case 'r':
2025 			if (!vc->vc_par[0])
2026 				vc->vc_par[0]++;
2027 			if (!vc->vc_par[1])
2028 				vc->vc_par[1] = vc->vc_rows;
2029 			/* Minimum allowed region is 2 lines */
2030 			if (vc->vc_par[0] < vc->vc_par[1] &&
2031 			    vc->vc_par[1] <= vc->vc_rows) {
2032 				vc->vc_top = vc->vc_par[0] - 1;
2033 				vc->vc_bottom = vc->vc_par[1];
2034 				gotoxay(vc, 0, 0);
2035 			}
2036 			return;
2037 		case 's':
2038 			save_cur(vc);
2039 			return;
2040 		case 'u':
2041 			restore_cur(vc);
2042 			return;
2043 		case 'X':
2044 			csi_X(vc, vc->vc_par[0]);
2045 			return;
2046 		case '@':
2047 			csi_at(vc, vc->vc_par[0]);
2048 			return;
2049 		case ']': /* setterm functions */
2050 			setterm_command(vc);
2051 			return;
2052 		}
2053 		return;
2054 	case ESpercent:
2055 		vc->vc_state = ESnormal;
2056 		switch (c) {
2057 		case '@':  /* defined in ISO 2022 */
2058 			vc->vc_utf = 0;
2059 			return;
2060 		case 'G':  /* prelim official escape code */
2061 		case '8':  /* retained for compatibility */
2062 			vc->vc_utf = 1;
2063 			return;
2064 		}
2065 		return;
2066 	case ESfunckey:
2067 		vc->vc_state = ESnormal;
2068 		return;
2069 	case EShash:
2070 		vc->vc_state = ESnormal;
2071 		if (c == '8') {
2072 			/* DEC screen alignment test. kludge :-) */
2073 			vc->vc_video_erase_char =
2074 				(vc->vc_video_erase_char & 0xff00) | 'E';
2075 			csi_J(vc, 2);
2076 			vc->vc_video_erase_char =
2077 				(vc->vc_video_erase_char & 0xff00) | ' ';
2078 			do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
2079 		}
2080 		return;
2081 	case ESsetG0:
2082 		if (c == '0')
2083 			vc->vc_G0_charset = GRAF_MAP;
2084 		else if (c == 'B')
2085 			vc->vc_G0_charset = LAT1_MAP;
2086 		else if (c == 'U')
2087 			vc->vc_G0_charset = IBMPC_MAP;
2088 		else if (c == 'K')
2089 			vc->vc_G0_charset = USER_MAP;
2090 		if (vc->vc_charset == 0)
2091 			vc->vc_translate = set_translate(vc->vc_G0_charset, vc);
2092 		vc->vc_state = ESnormal;
2093 		return;
2094 	case ESsetG1:
2095 		if (c == '0')
2096 			vc->vc_G1_charset = GRAF_MAP;
2097 		else if (c == 'B')
2098 			vc->vc_G1_charset = LAT1_MAP;
2099 		else if (c == 'U')
2100 			vc->vc_G1_charset = IBMPC_MAP;
2101 		else if (c == 'K')
2102 			vc->vc_G1_charset = USER_MAP;
2103 		if (vc->vc_charset == 1)
2104 			vc->vc_translate = set_translate(vc->vc_G1_charset, vc);
2105 		vc->vc_state = ESnormal;
2106 		return;
2107 	case ESosc:
2108 		return;
2109 	default:
2110 		vc->vc_state = ESnormal;
2111 	}
2112 }
2113 
2114 /* is_double_width() is based on the wcwidth() implementation by
2115  * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
2116  * Latest version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
2117  */
2118 struct interval {
2119 	uint32_t first;
2120 	uint32_t last;
2121 };
2122 
2123 static int bisearch(uint32_t ucs, const struct interval *table, int max)
2124 {
2125 	int min = 0;
2126 	int mid;
2127 
2128 	if (ucs < table[0].first || ucs > table[max].last)
2129 		return 0;
2130 	while (max >= min) {
2131 		mid = (min + max) / 2;
2132 		if (ucs > table[mid].last)
2133 			min = mid + 1;
2134 		else if (ucs < table[mid].first)
2135 			max = mid - 1;
2136 		else
2137 			return 1;
2138 	}
2139 	return 0;
2140 }
2141 
2142 static int is_double_width(uint32_t ucs)
2143 {
2144 	static const struct interval double_width[] = {
2145 		{ 0x1100, 0x115F }, { 0x2329, 0x232A }, { 0x2E80, 0x303E },
2146 		{ 0x3040, 0xA4CF }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF },
2147 		{ 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 },
2148 		{ 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }
2149 	};
2150 	return bisearch(ucs, double_width, ARRAY_SIZE(double_width) - 1);
2151 }
2152 
2153 /* acquires console_lock */
2154 static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int count)
2155 {
2156 #ifdef VT_BUF_VRAM_ONLY
2157 #define FLUSH do { } while(0);
2158 #else
2159 #define FLUSH if (draw_x >= 0) { \
2160 	vc->vc_sw->con_putcs(vc, (u16 *)draw_from, (u16 *)draw_to - (u16 *)draw_from, vc->vc_y, draw_x); \
2161 	draw_x = -1; \
2162 	}
2163 #endif
2164 
2165 	int c, tc, ok, n = 0, draw_x = -1;
2166 	unsigned int currcons;
2167 	unsigned long draw_from = 0, draw_to = 0;
2168 	struct vc_data *vc;
2169 	unsigned char vc_attr;
2170 	struct vt_notifier_param param;
2171 	uint8_t rescan;
2172 	uint8_t inverse;
2173 	uint8_t width;
2174 	u16 himask, charmask;
2175 
2176 	if (in_interrupt())
2177 		return count;
2178 
2179 	might_sleep();
2180 
2181 	console_lock();
2182 	vc = tty->driver_data;
2183 	if (vc == NULL) {
2184 		printk(KERN_ERR "vt: argh, driver_data is NULL !\n");
2185 		console_unlock();
2186 		return 0;
2187 	}
2188 
2189 	currcons = vc->vc_num;
2190 	if (!vc_cons_allocated(currcons)) {
2191 		/* could this happen? */
2192 		pr_warn_once("con_write: tty %d not allocated\n", currcons+1);
2193 		console_unlock();
2194 		return 0;
2195 	}
2196 
2197 	himask = vc->vc_hi_font_mask;
2198 	charmask = himask ? 0x1ff : 0xff;
2199 
2200 	/* undraw cursor first */
2201 	if (IS_FG(vc))
2202 		hide_cursor(vc);
2203 
2204 	param.vc = vc;
2205 
2206 	while (!tty->stopped && count) {
2207 		int orig = *buf;
2208 		c = orig;
2209 		buf++;
2210 		n++;
2211 		count--;
2212 		rescan = 0;
2213 		inverse = 0;
2214 		width = 1;
2215 
2216 		/* Do no translation at all in control states */
2217 		if (vc->vc_state != ESnormal) {
2218 			tc = c;
2219 		} else if (vc->vc_utf && !vc->vc_disp_ctrl) {
2220 		    /* Combine UTF-8 into Unicode in vc_utf_char.
2221 		     * vc_utf_count is the number of continuation bytes still
2222 		     * expected to arrive.
2223 		     * vc_npar is the number of continuation bytes arrived so
2224 		     * far
2225 		     */
2226 rescan_last_byte:
2227 		    if ((c & 0xc0) == 0x80) {
2228 			/* Continuation byte received */
2229 			static const uint32_t utf8_length_changes[] = { 0x0000007f, 0x000007ff, 0x0000ffff, 0x001fffff, 0x03ffffff, 0x7fffffff };
2230 			if (vc->vc_utf_count) {
2231 			    vc->vc_utf_char = (vc->vc_utf_char << 6) | (c & 0x3f);
2232 			    vc->vc_npar++;
2233 			    if (--vc->vc_utf_count) {
2234 				/* Still need some bytes */
2235 				continue;
2236 			    }
2237 			    /* Got a whole character */
2238 			    c = vc->vc_utf_char;
2239 			    /* Reject overlong sequences */
2240 			    if (c <= utf8_length_changes[vc->vc_npar - 1] ||
2241 					c > utf8_length_changes[vc->vc_npar])
2242 				c = 0xfffd;
2243 			} else {
2244 			    /* Unexpected continuation byte */
2245 			    vc->vc_utf_count = 0;
2246 			    c = 0xfffd;
2247 			}
2248 		    } else {
2249 			/* Single ASCII byte or first byte of a sequence received */
2250 			if (vc->vc_utf_count) {
2251 			    /* Continuation byte expected */
2252 			    rescan = 1;
2253 			    vc->vc_utf_count = 0;
2254 			    c = 0xfffd;
2255 			} else if (c > 0x7f) {
2256 			    /* First byte of a multibyte sequence received */
2257 			    vc->vc_npar = 0;
2258 			    if ((c & 0xe0) == 0xc0) {
2259 				vc->vc_utf_count = 1;
2260 				vc->vc_utf_char = (c & 0x1f);
2261 			    } else if ((c & 0xf0) == 0xe0) {
2262 				vc->vc_utf_count = 2;
2263 				vc->vc_utf_char = (c & 0x0f);
2264 			    } else if ((c & 0xf8) == 0xf0) {
2265 				vc->vc_utf_count = 3;
2266 				vc->vc_utf_char = (c & 0x07);
2267 			    } else if ((c & 0xfc) == 0xf8) {
2268 				vc->vc_utf_count = 4;
2269 				vc->vc_utf_char = (c & 0x03);
2270 			    } else if ((c & 0xfe) == 0xfc) {
2271 				vc->vc_utf_count = 5;
2272 				vc->vc_utf_char = (c & 0x01);
2273 			    } else {
2274 				/* 254 and 255 are invalid */
2275 				c = 0xfffd;
2276 			    }
2277 			    if (vc->vc_utf_count) {
2278 				/* Still need some bytes */
2279 				continue;
2280 			    }
2281 			}
2282 			/* Nothing to do if an ASCII byte was received */
2283 		    }
2284 		    /* End of UTF-8 decoding. */
2285 		    /* c is the received character, or U+FFFD for invalid sequences. */
2286 		    /* Replace invalid Unicode code points with U+FFFD too */
2287 		    if ((c >= 0xd800 && c <= 0xdfff) || c == 0xfffe || c == 0xffff)
2288 			c = 0xfffd;
2289 		    tc = c;
2290 		} else {	/* no utf or alternate charset mode */
2291 		    tc = vc_translate(vc, c);
2292 		}
2293 
2294 		param.c = tc;
2295 		if (atomic_notifier_call_chain(&vt_notifier_list, VT_PREWRITE,
2296 					&param) == NOTIFY_STOP)
2297 			continue;
2298 
2299                 /* If the original code was a control character we
2300                  * only allow a glyph to be displayed if the code is
2301                  * not normally used (such as for cursor movement) or
2302                  * if the disp_ctrl mode has been explicitly enabled.
2303                  * Certain characters (as given by the CTRL_ALWAYS
2304                  * bitmap) are always displayed as control characters,
2305                  * as the console would be pretty useless without
2306                  * them; to display an arbitrary font position use the
2307                  * direct-to-font zone in UTF-8 mode.
2308                  */
2309                 ok = tc && (c >= 32 ||
2310 			    !(vc->vc_disp_ctrl ? (CTRL_ALWAYS >> c) & 1 :
2311 				  vc->vc_utf || ((CTRL_ACTION >> c) & 1)))
2312 			&& (c != 127 || vc->vc_disp_ctrl)
2313 			&& (c != 128+27);
2314 
2315 		if (vc->vc_state == ESnormal && ok) {
2316 			if (vc->vc_utf && !vc->vc_disp_ctrl) {
2317 				if (is_double_width(c))
2318 					width = 2;
2319 			}
2320 			/* Now try to find out how to display it */
2321 			tc = conv_uni_to_pc(vc, tc);
2322 			if (tc & ~charmask) {
2323 				if (tc == -1 || tc == -2) {
2324 				    continue; /* nothing to display */
2325 				}
2326 				/* Glyph not found */
2327 				if ((!(vc->vc_utf && !vc->vc_disp_ctrl) || c < 128) && !(c & ~charmask)) {
2328 				    /* In legacy mode use the glyph we get by a 1:1 mapping.
2329 				       This would make absolutely no sense with Unicode in mind,
2330 				       but do this for ASCII characters since a font may lack
2331 				       Unicode mapping info and we don't want to end up with
2332 				       having question marks only. */
2333 				    tc = c;
2334 				} else {
2335 				    /* Display U+FFFD. If it's not found, display an inverse question mark. */
2336 				    tc = conv_uni_to_pc(vc, 0xfffd);
2337 				    if (tc < 0) {
2338 					inverse = 1;
2339 					tc = conv_uni_to_pc(vc, '?');
2340 					if (tc < 0) tc = '?';
2341 				    }
2342 				}
2343 			}
2344 
2345 			if (!inverse) {
2346 				vc_attr = vc->vc_attr;
2347 			} else {
2348 				/* invert vc_attr */
2349 				if (!vc->vc_can_do_color) {
2350 					vc_attr = (vc->vc_attr) ^ 0x08;
2351 				} else if (vc->vc_hi_font_mask == 0x100) {
2352 					vc_attr = ((vc->vc_attr) & 0x11) | (((vc->vc_attr) & 0xe0) >> 4) | (((vc->vc_attr) & 0x0e) << 4);
2353 				} else {
2354 					vc_attr = ((vc->vc_attr) & 0x88) | (((vc->vc_attr) & 0x70) >> 4) | (((vc->vc_attr) & 0x07) << 4);
2355 				}
2356 				FLUSH
2357 			}
2358 
2359 			while (1) {
2360 				if (vc->vc_need_wrap || vc->vc_decim)
2361 					FLUSH
2362 				if (vc->vc_need_wrap) {
2363 					cr(vc);
2364 					lf(vc);
2365 				}
2366 				if (vc->vc_decim)
2367 					insert_char(vc, 1);
2368 				scr_writew(himask ?
2369 					     ((vc_attr << 8) & ~himask) + ((tc & 0x100) ? himask : 0) + (tc & 0xff) :
2370 					     (vc_attr << 8) + tc,
2371 					   (u16 *) vc->vc_pos);
2372 				if (DO_UPDATE(vc) && draw_x < 0) {
2373 					draw_x = vc->vc_x;
2374 					draw_from = vc->vc_pos;
2375 				}
2376 				if (vc->vc_x == vc->vc_cols - 1) {
2377 					vc->vc_need_wrap = vc->vc_decawm;
2378 					draw_to = vc->vc_pos + 2;
2379 				} else {
2380 					vc->vc_x++;
2381 					draw_to = (vc->vc_pos += 2);
2382 				}
2383 
2384 				if (!--width) break;
2385 
2386 				tc = conv_uni_to_pc(vc, ' '); /* A space is printed in the second column */
2387 				if (tc < 0) tc = ' ';
2388 			}
2389 			notify_write(vc, c);
2390 
2391 			if (inverse) {
2392 				FLUSH
2393 			}
2394 
2395 			if (rescan) {
2396 				rescan = 0;
2397 				inverse = 0;
2398 				width = 1;
2399 				c = orig;
2400 				goto rescan_last_byte;
2401 			}
2402 			continue;
2403 		}
2404 		FLUSH
2405 		do_con_trol(tty, vc, orig);
2406 	}
2407 	FLUSH
2408 	console_conditional_schedule();
2409 	console_unlock();
2410 	notify_update(vc);
2411 	return n;
2412 #undef FLUSH
2413 }
2414 
2415 /*
2416  * This is the console switching callback.
2417  *
2418  * Doing console switching in a process context allows
2419  * us to do the switches asynchronously (needed when we want
2420  * to switch due to a keyboard interrupt).  Synchronization
2421  * with other console code and prevention of re-entrancy is
2422  * ensured with console_lock.
2423  */
2424 static void console_callback(struct work_struct *ignored)
2425 {
2426 	console_lock();
2427 
2428 	if (want_console >= 0) {
2429 		if (want_console != fg_console &&
2430 		    vc_cons_allocated(want_console)) {
2431 			hide_cursor(vc_cons[fg_console].d);
2432 			change_console(vc_cons[want_console].d);
2433 			/* we only changed when the console had already
2434 			   been allocated - a new console is not created
2435 			   in an interrupt routine */
2436 		}
2437 		want_console = -1;
2438 	}
2439 	if (do_poke_blanked_console) { /* do not unblank for a LED change */
2440 		do_poke_blanked_console = 0;
2441 		poke_blanked_console();
2442 	}
2443 	if (scrollback_delta) {
2444 		struct vc_data *vc = vc_cons[fg_console].d;
2445 		clear_selection();
2446 		if (vc->vc_mode == KD_TEXT)
2447 			vc->vc_sw->con_scrolldelta(vc, scrollback_delta);
2448 		scrollback_delta = 0;
2449 	}
2450 	if (blank_timer_expired) {
2451 		do_blank_screen(0);
2452 		blank_timer_expired = 0;
2453 	}
2454 	notify_update(vc_cons[fg_console].d);
2455 
2456 	console_unlock();
2457 }
2458 
2459 int set_console(int nr)
2460 {
2461 	struct vc_data *vc = vc_cons[fg_console].d;
2462 
2463 	if (!vc_cons_allocated(nr) || vt_dont_switch ||
2464 		(vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) {
2465 
2466 		/*
2467 		 * Console switch will fail in console_callback() or
2468 		 * change_console() so there is no point scheduling
2469 		 * the callback
2470 		 *
2471 		 * Existing set_console() users don't check the return
2472 		 * value so this shouldn't break anything
2473 		 */
2474 		return -EINVAL;
2475 	}
2476 
2477 	want_console = nr;
2478 	schedule_console_callback();
2479 
2480 	return 0;
2481 }
2482 
2483 struct tty_driver *console_driver;
2484 
2485 #ifdef CONFIG_VT_CONSOLE
2486 
2487 /**
2488  * vt_kmsg_redirect() - Sets/gets the kernel message console
2489  * @new:	The new virtual terminal number or -1 if the console should stay
2490  * 		unchanged
2491  *
2492  * By default, the kernel messages are always printed on the current virtual
2493  * console. However, the user may modify that default with the
2494  * TIOCL_SETKMSGREDIRECT ioctl call.
2495  *
2496  * This function sets the kernel message console to be @new. It returns the old
2497  * virtual console number. The virtual terminal number 0 (both as parameter and
2498  * return value) means no redirection (i.e. always printed on the currently
2499  * active console).
2500  *
2501  * The parameter -1 means that only the current console is returned, but the
2502  * value is not modified. You may use the macro vt_get_kmsg_redirect() in that
2503  * case to make the code more understandable.
2504  *
2505  * When the kernel is compiled without CONFIG_VT_CONSOLE, this function ignores
2506  * the parameter and always returns 0.
2507  */
2508 int vt_kmsg_redirect(int new)
2509 {
2510 	static int kmsg_con;
2511 
2512 	if (new != -1)
2513 		return xchg(&kmsg_con, new);
2514 	else
2515 		return kmsg_con;
2516 }
2517 
2518 /*
2519  *	Console on virtual terminal
2520  *
2521  * The console must be locked when we get here.
2522  */
2523 
2524 static void vt_console_print(struct console *co, const char *b, unsigned count)
2525 {
2526 	struct vc_data *vc = vc_cons[fg_console].d;
2527 	unsigned char c;
2528 	static DEFINE_SPINLOCK(printing_lock);
2529 	const ushort *start;
2530 	ushort cnt = 0;
2531 	ushort myx;
2532 	int kmsg_console;
2533 
2534 	/* console busy or not yet initialized */
2535 	if (!printable)
2536 		return;
2537 	if (!spin_trylock(&printing_lock))
2538 		return;
2539 
2540 	kmsg_console = vt_get_kmsg_redirect();
2541 	if (kmsg_console && vc_cons_allocated(kmsg_console - 1))
2542 		vc = vc_cons[kmsg_console - 1].d;
2543 
2544 	/* read `x' only after setting currcons properly (otherwise
2545 	   the `x' macro will read the x of the foreground console). */
2546 	myx = vc->vc_x;
2547 
2548 	if (!vc_cons_allocated(fg_console)) {
2549 		/* impossible */
2550 		/* printk("vt_console_print: tty %d not allocated ??\n", currcons+1); */
2551 		goto quit;
2552 	}
2553 
2554 	if (vc->vc_mode != KD_TEXT && !vt_force_oops_output(vc))
2555 		goto quit;
2556 
2557 	/* undraw cursor first */
2558 	if (IS_FG(vc))
2559 		hide_cursor(vc);
2560 
2561 	start = (ushort *)vc->vc_pos;
2562 
2563 	/* Contrived structure to try to emulate original need_wrap behaviour
2564 	 * Problems caused when we have need_wrap set on '\n' character */
2565 	while (count--) {
2566 		c = *b++;
2567 		if (c == 10 || c == 13 || c == 8 || vc->vc_need_wrap) {
2568 			if (cnt > 0) {
2569 				if (CON_IS_VISIBLE(vc))
2570 					vc->vc_sw->con_putcs(vc, start, cnt, vc->vc_y, vc->vc_x);
2571 				vc->vc_x += cnt;
2572 				if (vc->vc_need_wrap)
2573 					vc->vc_x--;
2574 				cnt = 0;
2575 			}
2576 			if (c == 8) {		/* backspace */
2577 				bs(vc);
2578 				start = (ushort *)vc->vc_pos;
2579 				myx = vc->vc_x;
2580 				continue;
2581 			}
2582 			if (c != 13)
2583 				lf(vc);
2584 			cr(vc);
2585 			start = (ushort *)vc->vc_pos;
2586 			myx = vc->vc_x;
2587 			if (c == 10 || c == 13)
2588 				continue;
2589 		}
2590 		scr_writew((vc->vc_attr << 8) + c, (unsigned short *)vc->vc_pos);
2591 		notify_write(vc, c);
2592 		cnt++;
2593 		if (myx == vc->vc_cols - 1) {
2594 			vc->vc_need_wrap = 1;
2595 			continue;
2596 		}
2597 		vc->vc_pos += 2;
2598 		myx++;
2599 	}
2600 	if (cnt > 0) {
2601 		if (CON_IS_VISIBLE(vc))
2602 			vc->vc_sw->con_putcs(vc, start, cnt, vc->vc_y, vc->vc_x);
2603 		vc->vc_x += cnt;
2604 		if (vc->vc_x == vc->vc_cols) {
2605 			vc->vc_x--;
2606 			vc->vc_need_wrap = 1;
2607 		}
2608 	}
2609 	set_cursor(vc);
2610 	notify_update(vc);
2611 
2612 quit:
2613 	spin_unlock(&printing_lock);
2614 }
2615 
2616 static struct tty_driver *vt_console_device(struct console *c, int *index)
2617 {
2618 	*index = c->index ? c->index-1 : fg_console;
2619 	return console_driver;
2620 }
2621 
2622 static struct console vt_console_driver = {
2623 	.name		= "tty",
2624 	.write		= vt_console_print,
2625 	.device		= vt_console_device,
2626 	.unblank	= unblank_screen,
2627 	.flags		= CON_PRINTBUFFER,
2628 	.index		= -1,
2629 };
2630 #endif
2631 
2632 /*
2633  *	Handling of Linux-specific VC ioctls
2634  */
2635 
2636 /*
2637  * Generally a bit racy with respect to console_lock();.
2638  *
2639  * There are some functions which don't need it.
2640  *
2641  * There are some functions which can sleep for arbitrary periods
2642  * (paste_selection) but we don't need the lock there anyway.
2643  *
2644  * set_selection has locking, and definitely needs it
2645  */
2646 
2647 int tioclinux(struct tty_struct *tty, unsigned long arg)
2648 {
2649 	char type, data;
2650 	char __user *p = (char __user *)arg;
2651 	int lines;
2652 	int ret;
2653 
2654 	if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
2655 		return -EPERM;
2656 	if (get_user(type, p))
2657 		return -EFAULT;
2658 	ret = 0;
2659 
2660 	switch (type)
2661 	{
2662 		case TIOCL_SETSEL:
2663 			console_lock();
2664 			ret = set_selection((struct tiocl_selection __user *)(p+1), tty);
2665 			console_unlock();
2666 			break;
2667 		case TIOCL_PASTESEL:
2668 			ret = paste_selection(tty);
2669 			break;
2670 		case TIOCL_UNBLANKSCREEN:
2671 			console_lock();
2672 			unblank_screen();
2673 			console_unlock();
2674 			break;
2675 		case TIOCL_SELLOADLUT:
2676 			console_lock();
2677 			ret = sel_loadlut(p);
2678 			console_unlock();
2679 			break;
2680 		case TIOCL_GETSHIFTSTATE:
2681 
2682 	/*
2683 	 * Make it possible to react to Shift+Mousebutton.
2684 	 * Note that 'shift_state' is an undocumented
2685 	 * kernel-internal variable; programs not closely
2686 	 * related to the kernel should not use this.
2687 	 */
2688 			data = vt_get_shift_state();
2689 			ret = __put_user(data, p);
2690 			break;
2691 		case TIOCL_GETMOUSEREPORTING:
2692 			console_lock();	/* May be overkill */
2693 			data = mouse_reporting();
2694 			console_unlock();
2695 			ret = __put_user(data, p);
2696 			break;
2697 		case TIOCL_SETVESABLANK:
2698 			console_lock();
2699 			ret = set_vesa_blanking(p);
2700 			console_unlock();
2701 			break;
2702 		case TIOCL_GETKMSGREDIRECT:
2703 			data = vt_get_kmsg_redirect();
2704 			ret = __put_user(data, p);
2705 			break;
2706 		case TIOCL_SETKMSGREDIRECT:
2707 			if (!capable(CAP_SYS_ADMIN)) {
2708 				ret = -EPERM;
2709 			} else {
2710 				if (get_user(data, p+1))
2711 					ret = -EFAULT;
2712 				else
2713 					vt_kmsg_redirect(data);
2714 			}
2715 			break;
2716 		case TIOCL_GETFGCONSOLE:
2717 			/* No locking needed as this is a transiently
2718 			   correct return anyway if the caller hasn't
2719 			   disabled switching */
2720 			ret = fg_console;
2721 			break;
2722 		case TIOCL_SCROLLCONSOLE:
2723 			if (get_user(lines, (s32 __user *)(p+4))) {
2724 				ret = -EFAULT;
2725 			} else {
2726 				/* Need the console lock here. Note that lots
2727 				   of other calls need fixing before the lock
2728 				   is actually useful ! */
2729 				console_lock();
2730 				scrollfront(vc_cons[fg_console].d, lines);
2731 				console_unlock();
2732 				ret = 0;
2733 			}
2734 			break;
2735 		case TIOCL_BLANKSCREEN:	/* until explicitly unblanked, not only poked */
2736 			console_lock();
2737 			ignore_poke = 1;
2738 			do_blank_screen(0);
2739 			console_unlock();
2740 			break;
2741 		case TIOCL_BLANKEDSCREEN:
2742 			ret = console_blanked;
2743 			break;
2744 		default:
2745 			ret = -EINVAL;
2746 			break;
2747 	}
2748 	return ret;
2749 }
2750 
2751 /*
2752  * /dev/ttyN handling
2753  */
2754 
2755 static int con_write(struct tty_struct *tty, const unsigned char *buf, int count)
2756 {
2757 	int	retval;
2758 
2759 	retval = do_con_write(tty, buf, count);
2760 	con_flush_chars(tty);
2761 
2762 	return retval;
2763 }
2764 
2765 static int con_put_char(struct tty_struct *tty, unsigned char ch)
2766 {
2767 	if (in_interrupt())
2768 		return 0;	/* n_r3964 calls put_char() from interrupt context */
2769 	return do_con_write(tty, &ch, 1);
2770 }
2771 
2772 static int con_write_room(struct tty_struct *tty)
2773 {
2774 	if (tty->stopped)
2775 		return 0;
2776 	return 32768;		/* No limit, really; we're not buffering */
2777 }
2778 
2779 static int con_chars_in_buffer(struct tty_struct *tty)
2780 {
2781 	return 0;		/* we're not buffering */
2782 }
2783 
2784 /*
2785  * con_throttle and con_unthrottle are only used for
2786  * paste_selection(), which has to stuff in a large number of
2787  * characters...
2788  */
2789 static void con_throttle(struct tty_struct *tty)
2790 {
2791 }
2792 
2793 static void con_unthrottle(struct tty_struct *tty)
2794 {
2795 	struct vc_data *vc = tty->driver_data;
2796 
2797 	wake_up_interruptible(&vc->paste_wait);
2798 }
2799 
2800 /*
2801  * Turn the Scroll-Lock LED on when the tty is stopped
2802  */
2803 static void con_stop(struct tty_struct *tty)
2804 {
2805 	int console_num;
2806 	if (!tty)
2807 		return;
2808 	console_num = tty->index;
2809 	if (!vc_cons_allocated(console_num))
2810 		return;
2811 	vt_kbd_con_stop(console_num);
2812 }
2813 
2814 /*
2815  * Turn the Scroll-Lock LED off when the console is started
2816  */
2817 static void con_start(struct tty_struct *tty)
2818 {
2819 	int console_num;
2820 	if (!tty)
2821 		return;
2822 	console_num = tty->index;
2823 	if (!vc_cons_allocated(console_num))
2824 		return;
2825 	vt_kbd_con_start(console_num);
2826 }
2827 
2828 static void con_flush_chars(struct tty_struct *tty)
2829 {
2830 	struct vc_data *vc;
2831 
2832 	if (in_interrupt())	/* from flush_to_ldisc */
2833 		return;
2834 
2835 	/* if we race with con_close(), vt may be null */
2836 	console_lock();
2837 	vc = tty->driver_data;
2838 	if (vc)
2839 		set_cursor(vc);
2840 	console_unlock();
2841 }
2842 
2843 /*
2844  * Allocate the console screen memory.
2845  */
2846 static int con_install(struct tty_driver *driver, struct tty_struct *tty)
2847 {
2848 	unsigned int currcons = tty->index;
2849 	struct vc_data *vc;
2850 	int ret;
2851 
2852 	console_lock();
2853 	ret = vc_allocate(currcons);
2854 	if (ret)
2855 		goto unlock;
2856 
2857 	vc = vc_cons[currcons].d;
2858 
2859 	/* Still being freed */
2860 	if (vc->port.tty) {
2861 		ret = -ERESTARTSYS;
2862 		goto unlock;
2863 	}
2864 
2865 	ret = tty_port_install(&vc->port, driver, tty);
2866 	if (ret)
2867 		goto unlock;
2868 
2869 	tty->driver_data = vc;
2870 	vc->port.tty = tty;
2871 
2872 	if (!tty->winsize.ws_row && !tty->winsize.ws_col) {
2873 		tty->winsize.ws_row = vc_cons[currcons].d->vc_rows;
2874 		tty->winsize.ws_col = vc_cons[currcons].d->vc_cols;
2875 	}
2876 	if (vc->vc_utf)
2877 		tty->termios.c_iflag |= IUTF8;
2878 	else
2879 		tty->termios.c_iflag &= ~IUTF8;
2880 unlock:
2881 	console_unlock();
2882 	return ret;
2883 }
2884 
2885 static int con_open(struct tty_struct *tty, struct file *filp)
2886 {
2887 	/* everything done in install */
2888 	return 0;
2889 }
2890 
2891 
2892 static void con_close(struct tty_struct *tty, struct file *filp)
2893 {
2894 	/* Nothing to do - we defer to shutdown */
2895 }
2896 
2897 static void con_shutdown(struct tty_struct *tty)
2898 {
2899 	struct vc_data *vc = tty->driver_data;
2900 	BUG_ON(vc == NULL);
2901 	console_lock();
2902 	vc->port.tty = NULL;
2903 	console_unlock();
2904 }
2905 
2906 static int default_color           = 7; /* white */
2907 static int default_italic_color    = 2; // green (ASCII)
2908 static int default_underline_color = 3; // cyan (ASCII)
2909 module_param_named(color, default_color, int, S_IRUGO | S_IWUSR);
2910 module_param_named(italic, default_italic_color, int, S_IRUGO | S_IWUSR);
2911 module_param_named(underline, default_underline_color, int, S_IRUGO | S_IWUSR);
2912 
2913 static void vc_init(struct vc_data *vc, unsigned int rows,
2914 		    unsigned int cols, int do_clear)
2915 {
2916 	int j, k ;
2917 
2918 	vc->vc_cols = cols;
2919 	vc->vc_rows = rows;
2920 	vc->vc_size_row = cols << 1;
2921 	vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
2922 
2923 	set_origin(vc);
2924 	vc->vc_pos = vc->vc_origin;
2925 	reset_vc(vc);
2926 	for (j=k=0; j<16; j++) {
2927 		vc->vc_palette[k++] = default_red[j] ;
2928 		vc->vc_palette[k++] = default_grn[j] ;
2929 		vc->vc_palette[k++] = default_blu[j] ;
2930 	}
2931 	vc->vc_def_color       = default_color;
2932 	vc->vc_ulcolor         = default_underline_color;
2933 	vc->vc_itcolor         = default_italic_color;
2934 	vc->vc_halfcolor       = 0x08;   /* grey */
2935 	init_waitqueue_head(&vc->paste_wait);
2936 	reset_terminal(vc, do_clear);
2937 }
2938 
2939 /*
2940  * This routine initializes console interrupts, and does nothing
2941  * else. If you want the screen to clear, call tty_write with
2942  * the appropriate escape-sequence.
2943  */
2944 
2945 static int __init con_init(void)
2946 {
2947 	const char *display_desc = NULL;
2948 	struct vc_data *vc;
2949 	unsigned int currcons = 0, i;
2950 
2951 	console_lock();
2952 
2953 	if (conswitchp)
2954 		display_desc = conswitchp->con_startup();
2955 	if (!display_desc) {
2956 		fg_console = 0;
2957 		console_unlock();
2958 		return 0;
2959 	}
2960 
2961 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
2962 		struct con_driver *con_driver = &registered_con_driver[i];
2963 
2964 		if (con_driver->con == NULL) {
2965 			con_driver->con = conswitchp;
2966 			con_driver->desc = display_desc;
2967 			con_driver->flag = CON_DRIVER_FLAG_INIT;
2968 			con_driver->first = 0;
2969 			con_driver->last = MAX_NR_CONSOLES - 1;
2970 			break;
2971 		}
2972 	}
2973 
2974 	for (i = 0; i < MAX_NR_CONSOLES; i++)
2975 		con_driver_map[i] = conswitchp;
2976 
2977 	if (blankinterval) {
2978 		blank_state = blank_normal_wait;
2979 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
2980 	}
2981 
2982 	for (currcons = 0; currcons < MIN_NR_CONSOLES; currcons++) {
2983 		vc_cons[currcons].d = vc = kzalloc(sizeof(struct vc_data), GFP_NOWAIT);
2984 		INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
2985 		tty_port_init(&vc->port);
2986 		visual_init(vc, currcons, 1);
2987 		vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_NOWAIT);
2988 		vc_init(vc, vc->vc_rows, vc->vc_cols,
2989 			currcons || !vc->vc_sw->con_save_screen);
2990 	}
2991 	currcons = fg_console = 0;
2992 	master_display_fg = vc = vc_cons[currcons].d;
2993 	set_origin(vc);
2994 	save_screen(vc);
2995 	gotoxy(vc, vc->vc_x, vc->vc_y);
2996 	csi_J(vc, 0);
2997 	update_screen(vc);
2998 	pr_info("Console: %s %s %dx%d\n",
2999 		vc->vc_can_do_color ? "colour" : "mono",
3000 		display_desc, vc->vc_cols, vc->vc_rows);
3001 	printable = 1;
3002 
3003 	console_unlock();
3004 
3005 #ifdef CONFIG_VT_CONSOLE
3006 	register_console(&vt_console_driver);
3007 #endif
3008 	return 0;
3009 }
3010 console_initcall(con_init);
3011 
3012 static const struct tty_operations con_ops = {
3013 	.install = con_install,
3014 	.open = con_open,
3015 	.close = con_close,
3016 	.write = con_write,
3017 	.write_room = con_write_room,
3018 	.put_char = con_put_char,
3019 	.flush_chars = con_flush_chars,
3020 	.chars_in_buffer = con_chars_in_buffer,
3021 	.ioctl = vt_ioctl,
3022 #ifdef CONFIG_COMPAT
3023 	.compat_ioctl = vt_compat_ioctl,
3024 #endif
3025 	.stop = con_stop,
3026 	.start = con_start,
3027 	.throttle = con_throttle,
3028 	.unthrottle = con_unthrottle,
3029 	.resize = vt_resize,
3030 	.shutdown = con_shutdown
3031 };
3032 
3033 static struct cdev vc0_cdev;
3034 
3035 static ssize_t show_tty_active(struct device *dev,
3036 				struct device_attribute *attr, char *buf)
3037 {
3038 	return sprintf(buf, "tty%d\n", fg_console + 1);
3039 }
3040 static DEVICE_ATTR(active, S_IRUGO, show_tty_active, NULL);
3041 
3042 int __init vty_init(const struct file_operations *console_fops)
3043 {
3044 	cdev_init(&vc0_cdev, console_fops);
3045 	if (cdev_add(&vc0_cdev, MKDEV(TTY_MAJOR, 0), 1) ||
3046 	    register_chrdev_region(MKDEV(TTY_MAJOR, 0), 1, "/dev/vc/0") < 0)
3047 		panic("Couldn't register /dev/tty0 driver\n");
3048 	tty0dev = device_create(tty_class, NULL, MKDEV(TTY_MAJOR, 0), NULL, "tty0");
3049 	if (IS_ERR(tty0dev))
3050 		tty0dev = NULL;
3051 	else
3052 		WARN_ON(device_create_file(tty0dev, &dev_attr_active) < 0);
3053 
3054 	vcs_init();
3055 
3056 	console_driver = alloc_tty_driver(MAX_NR_CONSOLES);
3057 	if (!console_driver)
3058 		panic("Couldn't allocate console driver\n");
3059 
3060 	console_driver->name = "tty";
3061 	console_driver->name_base = 1;
3062 	console_driver->major = TTY_MAJOR;
3063 	console_driver->minor_start = 1;
3064 	console_driver->type = TTY_DRIVER_TYPE_CONSOLE;
3065 	console_driver->init_termios = tty_std_termios;
3066 	if (default_utf8)
3067 		console_driver->init_termios.c_iflag |= IUTF8;
3068 	console_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS;
3069 	tty_set_operations(console_driver, &con_ops);
3070 	if (tty_register_driver(console_driver))
3071 		panic("Couldn't register console driver\n");
3072 	kbd_init();
3073 	console_map_init();
3074 #ifdef CONFIG_MDA_CONSOLE
3075 	mda_console_init();
3076 #endif
3077 	return 0;
3078 }
3079 
3080 #ifndef VT_SINGLE_DRIVER
3081 
3082 static struct class *vtconsole_class;
3083 
3084 static int do_bind_con_driver(const struct consw *csw, int first, int last,
3085 			   int deflt)
3086 {
3087 	struct module *owner = csw->owner;
3088 	const char *desc = NULL;
3089 	struct con_driver *con_driver;
3090 	int i, j = -1, k = -1, retval = -ENODEV;
3091 
3092 	if (!try_module_get(owner))
3093 		return -ENODEV;
3094 
3095 	WARN_CONSOLE_UNLOCKED();
3096 
3097 	/* check if driver is registered */
3098 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3099 		con_driver = &registered_con_driver[i];
3100 
3101 		if (con_driver->con == csw) {
3102 			desc = con_driver->desc;
3103 			retval = 0;
3104 			break;
3105 		}
3106 	}
3107 
3108 	if (retval)
3109 		goto err;
3110 
3111 	if (!(con_driver->flag & CON_DRIVER_FLAG_INIT)) {
3112 		csw->con_startup();
3113 		con_driver->flag |= CON_DRIVER_FLAG_INIT;
3114 	}
3115 
3116 	if (deflt) {
3117 		if (conswitchp)
3118 			module_put(conswitchp->owner);
3119 
3120 		__module_get(owner);
3121 		conswitchp = csw;
3122 	}
3123 
3124 	first = max(first, con_driver->first);
3125 	last = min(last, con_driver->last);
3126 
3127 	for (i = first; i <= last; i++) {
3128 		int old_was_color;
3129 		struct vc_data *vc = vc_cons[i].d;
3130 
3131 		if (con_driver_map[i])
3132 			module_put(con_driver_map[i]->owner);
3133 		__module_get(owner);
3134 		con_driver_map[i] = csw;
3135 
3136 		if (!vc || !vc->vc_sw)
3137 			continue;
3138 
3139 		j = i;
3140 
3141 		if (CON_IS_VISIBLE(vc)) {
3142 			k = i;
3143 			save_screen(vc);
3144 		}
3145 
3146 		old_was_color = vc->vc_can_do_color;
3147 		vc->vc_sw->con_deinit(vc);
3148 		vc->vc_origin = (unsigned long)vc->vc_screenbuf;
3149 		visual_init(vc, i, 0);
3150 		set_origin(vc);
3151 		update_attr(vc);
3152 
3153 		/* If the console changed between mono <-> color, then
3154 		 * the attributes in the screenbuf will be wrong.  The
3155 		 * following resets all attributes to something sane.
3156 		 */
3157 		if (old_was_color != vc->vc_can_do_color)
3158 			clear_buffer_attributes(vc);
3159 	}
3160 
3161 	pr_info("Console: switching ");
3162 	if (!deflt)
3163 		printk("consoles %d-%d ", first+1, last+1);
3164 	if (j >= 0) {
3165 		struct vc_data *vc = vc_cons[j].d;
3166 
3167 		printk("to %s %s %dx%d\n",
3168 		       vc->vc_can_do_color ? "colour" : "mono",
3169 		       desc, vc->vc_cols, vc->vc_rows);
3170 
3171 		if (k >= 0) {
3172 			vc = vc_cons[k].d;
3173 			update_screen(vc);
3174 		}
3175 	} else
3176 		printk("to %s\n", desc);
3177 
3178 	retval = 0;
3179 err:
3180 	module_put(owner);
3181 	return retval;
3182 };
3183 
3184 
3185 #ifdef CONFIG_VT_HW_CONSOLE_BINDING
3186 static int con_is_graphics(const struct consw *csw, int first, int last)
3187 {
3188 	int i, retval = 0;
3189 
3190 	for (i = first; i <= last; i++) {
3191 		struct vc_data *vc = vc_cons[i].d;
3192 
3193 		if (vc && vc->vc_mode == KD_GRAPHICS) {
3194 			retval = 1;
3195 			break;
3196 		}
3197 	}
3198 
3199 	return retval;
3200 }
3201 
3202 /* unlocked version of unbind_con_driver() */
3203 int do_unbind_con_driver(const struct consw *csw, int first, int last, int deflt)
3204 {
3205 	struct module *owner = csw->owner;
3206 	const struct consw *defcsw = NULL;
3207 	struct con_driver *con_driver = NULL, *con_back = NULL;
3208 	int i, retval = -ENODEV;
3209 
3210 	if (!try_module_get(owner))
3211 		return -ENODEV;
3212 
3213 	WARN_CONSOLE_UNLOCKED();
3214 
3215 	/* check if driver is registered and if it is unbindable */
3216 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3217 		con_driver = &registered_con_driver[i];
3218 
3219 		if (con_driver->con == csw &&
3220 		    con_driver->flag & CON_DRIVER_FLAG_MODULE) {
3221 			retval = 0;
3222 			break;
3223 		}
3224 	}
3225 
3226 	if (retval)
3227 		goto err;
3228 
3229 	retval = -ENODEV;
3230 
3231 	/* check if backup driver exists */
3232 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3233 		con_back = &registered_con_driver[i];
3234 
3235 		if (con_back->con && con_back->con != csw) {
3236 			defcsw = con_back->con;
3237 			retval = 0;
3238 			break;
3239 		}
3240 	}
3241 
3242 	if (retval)
3243 		goto err;
3244 
3245 	if (!con_is_bound(csw))
3246 		goto err;
3247 
3248 	first = max(first, con_driver->first);
3249 	last = min(last, con_driver->last);
3250 
3251 	for (i = first; i <= last; i++) {
3252 		if (con_driver_map[i] == csw) {
3253 			module_put(csw->owner);
3254 			con_driver_map[i] = NULL;
3255 		}
3256 	}
3257 
3258 	if (!con_is_bound(defcsw)) {
3259 		const struct consw *defconsw = conswitchp;
3260 
3261 		defcsw->con_startup();
3262 		con_back->flag |= CON_DRIVER_FLAG_INIT;
3263 		/*
3264 		 * vgacon may change the default driver to point
3265 		 * to dummycon, we restore it here...
3266 		 */
3267 		conswitchp = defconsw;
3268 	}
3269 
3270 	if (!con_is_bound(csw))
3271 		con_driver->flag &= ~CON_DRIVER_FLAG_INIT;
3272 
3273 	/* ignore return value, binding should not fail */
3274 	do_bind_con_driver(defcsw, first, last, deflt);
3275 err:
3276 	module_put(owner);
3277 	return retval;
3278 
3279 }
3280 EXPORT_SYMBOL_GPL(do_unbind_con_driver);
3281 
3282 static int vt_bind(struct con_driver *con)
3283 {
3284 	const struct consw *defcsw = NULL, *csw = NULL;
3285 	int i, more = 1, first = -1, last = -1, deflt = 0;
3286 
3287  	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE) ||
3288 	    con_is_graphics(con->con, con->first, con->last))
3289 		goto err;
3290 
3291 	csw = con->con;
3292 
3293 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3294 		struct con_driver *con = &registered_con_driver[i];
3295 
3296 		if (con->con && !(con->flag & CON_DRIVER_FLAG_MODULE)) {
3297 			defcsw = con->con;
3298 			break;
3299 		}
3300 	}
3301 
3302 	if (!defcsw)
3303 		goto err;
3304 
3305 	while (more) {
3306 		more = 0;
3307 
3308 		for (i = con->first; i <= con->last; i++) {
3309 			if (con_driver_map[i] == defcsw) {
3310 				if (first == -1)
3311 					first = i;
3312 				last = i;
3313 				more = 1;
3314 			} else if (first != -1)
3315 				break;
3316 		}
3317 
3318 		if (first == 0 && last == MAX_NR_CONSOLES -1)
3319 			deflt = 1;
3320 
3321 		if (first != -1) {
3322 			console_lock();
3323 			do_bind_con_driver(csw, first, last, deflt);
3324 			console_unlock();
3325 		}
3326 
3327 		first = -1;
3328 		last = -1;
3329 		deflt = 0;
3330 	}
3331 
3332 err:
3333 	return 0;
3334 }
3335 
3336 static int vt_unbind(struct con_driver *con)
3337 {
3338 	const struct consw *csw = NULL;
3339 	int i, more = 1, first = -1, last = -1, deflt = 0;
3340 	int ret;
3341 
3342  	if (!con->con || !(con->flag & CON_DRIVER_FLAG_MODULE) ||
3343 	    con_is_graphics(con->con, con->first, con->last))
3344 		goto err;
3345 
3346 	csw = con->con;
3347 
3348 	while (more) {
3349 		more = 0;
3350 
3351 		for (i = con->first; i <= con->last; i++) {
3352 			if (con_driver_map[i] == csw) {
3353 				if (first == -1)
3354 					first = i;
3355 				last = i;
3356 				more = 1;
3357 			} else if (first != -1)
3358 				break;
3359 		}
3360 
3361 		if (first == 0 && last == MAX_NR_CONSOLES -1)
3362 			deflt = 1;
3363 
3364 		if (first != -1) {
3365 			console_lock();
3366 			ret = do_unbind_con_driver(csw, first, last, deflt);
3367 			console_unlock();
3368 			if (ret != 0)
3369 				return ret;
3370 		}
3371 
3372 		first = -1;
3373 		last = -1;
3374 		deflt = 0;
3375 	}
3376 
3377 err:
3378 	return 0;
3379 }
3380 #else
3381 static inline int vt_bind(struct con_driver *con)
3382 {
3383 	return 0;
3384 }
3385 static inline int vt_unbind(struct con_driver *con)
3386 {
3387 	return 0;
3388 }
3389 #endif /* CONFIG_VT_HW_CONSOLE_BINDING */
3390 
3391 static ssize_t store_bind(struct device *dev, struct device_attribute *attr,
3392 			  const char *buf, size_t count)
3393 {
3394 	struct con_driver *con = dev_get_drvdata(dev);
3395 	int bind = simple_strtoul(buf, NULL, 0);
3396 
3397 	if (bind)
3398 		vt_bind(con);
3399 	else
3400 		vt_unbind(con);
3401 
3402 	return count;
3403 }
3404 
3405 static ssize_t show_bind(struct device *dev, struct device_attribute *attr,
3406 			 char *buf)
3407 {
3408 	struct con_driver *con = dev_get_drvdata(dev);
3409 	int bind = con_is_bound(con->con);
3410 
3411 	return snprintf(buf, PAGE_SIZE, "%i\n", bind);
3412 }
3413 
3414 static ssize_t show_name(struct device *dev, struct device_attribute *attr,
3415 			 char *buf)
3416 {
3417 	struct con_driver *con = dev_get_drvdata(dev);
3418 
3419 	return snprintf(buf, PAGE_SIZE, "%s %s\n",
3420 			(con->flag & CON_DRIVER_FLAG_MODULE) ? "(M)" : "(S)",
3421 			 con->desc);
3422 
3423 }
3424 
3425 static struct device_attribute device_attrs[] = {
3426 	__ATTR(bind, S_IRUGO|S_IWUSR, show_bind, store_bind),
3427 	__ATTR(name, S_IRUGO, show_name, NULL),
3428 };
3429 
3430 static int vtconsole_init_device(struct con_driver *con)
3431 {
3432 	int i;
3433 	int error = 0;
3434 
3435 	con->flag |= CON_DRIVER_FLAG_ATTR;
3436 	dev_set_drvdata(con->dev, con);
3437 	for (i = 0; i < ARRAY_SIZE(device_attrs); i++) {
3438 		error = device_create_file(con->dev, &device_attrs[i]);
3439 		if (error)
3440 			break;
3441 	}
3442 
3443 	if (error) {
3444 		while (--i >= 0)
3445 			device_remove_file(con->dev, &device_attrs[i]);
3446 		con->flag &= ~CON_DRIVER_FLAG_ATTR;
3447 	}
3448 
3449 	return error;
3450 }
3451 
3452 static void vtconsole_deinit_device(struct con_driver *con)
3453 {
3454 	int i;
3455 
3456 	if (con->flag & CON_DRIVER_FLAG_ATTR) {
3457 		for (i = 0; i < ARRAY_SIZE(device_attrs); i++)
3458 			device_remove_file(con->dev, &device_attrs[i]);
3459 		con->flag &= ~CON_DRIVER_FLAG_ATTR;
3460 	}
3461 }
3462 
3463 /**
3464  * con_is_bound - checks if driver is bound to the console
3465  * @csw: console driver
3466  *
3467  * RETURNS: zero if unbound, nonzero if bound
3468  *
3469  * Drivers can call this and if zero, they should release
3470  * all resources allocated on con_startup()
3471  */
3472 int con_is_bound(const struct consw *csw)
3473 {
3474 	int i, bound = 0;
3475 
3476 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
3477 		if (con_driver_map[i] == csw) {
3478 			bound = 1;
3479 			break;
3480 		}
3481 	}
3482 
3483 	return bound;
3484 }
3485 EXPORT_SYMBOL(con_is_bound);
3486 
3487 /**
3488  * con_debug_enter - prepare the console for the kernel debugger
3489  * @sw: console driver
3490  *
3491  * Called when the console is taken over by the kernel debugger, this
3492  * function needs to save the current console state, then put the console
3493  * into a state suitable for the kernel debugger.
3494  *
3495  * RETURNS:
3496  * Zero on success, nonzero if a failure occurred when trying to prepare
3497  * the console for the debugger.
3498  */
3499 int con_debug_enter(struct vc_data *vc)
3500 {
3501 	int ret = 0;
3502 
3503 	saved_fg_console = fg_console;
3504 	saved_last_console = last_console;
3505 	saved_want_console = want_console;
3506 	saved_vc_mode = vc->vc_mode;
3507 	saved_console_blanked = console_blanked;
3508 	vc->vc_mode = KD_TEXT;
3509 	console_blanked = 0;
3510 	if (vc->vc_sw->con_debug_enter)
3511 		ret = vc->vc_sw->con_debug_enter(vc);
3512 #ifdef CONFIG_KGDB_KDB
3513 	/* Set the initial LINES variable if it is not already set */
3514 	if (vc->vc_rows < 999) {
3515 		int linecount;
3516 		char lns[4];
3517 		const char *setargs[3] = {
3518 			"set",
3519 			"LINES",
3520 			lns,
3521 		};
3522 		if (kdbgetintenv(setargs[0], &linecount)) {
3523 			snprintf(lns, 4, "%i", vc->vc_rows);
3524 			kdb_set(2, setargs);
3525 		}
3526 	}
3527 	if (vc->vc_cols < 999) {
3528 		int colcount;
3529 		char cols[4];
3530 		const char *setargs[3] = {
3531 			"set",
3532 			"COLUMNS",
3533 			cols,
3534 		};
3535 		if (kdbgetintenv(setargs[0], &colcount)) {
3536 			snprintf(cols, 4, "%i", vc->vc_cols);
3537 			kdb_set(2, setargs);
3538 		}
3539 	}
3540 #endif /* CONFIG_KGDB_KDB */
3541 	return ret;
3542 }
3543 EXPORT_SYMBOL_GPL(con_debug_enter);
3544 
3545 /**
3546  * con_debug_leave - restore console state
3547  * @sw: console driver
3548  *
3549  * Restore the console state to what it was before the kernel debugger
3550  * was invoked.
3551  *
3552  * RETURNS:
3553  * Zero on success, nonzero if a failure occurred when trying to restore
3554  * the console.
3555  */
3556 int con_debug_leave(void)
3557 {
3558 	struct vc_data *vc;
3559 	int ret = 0;
3560 
3561 	fg_console = saved_fg_console;
3562 	last_console = saved_last_console;
3563 	want_console = saved_want_console;
3564 	console_blanked = saved_console_blanked;
3565 	vc_cons[fg_console].d->vc_mode = saved_vc_mode;
3566 
3567 	vc = vc_cons[fg_console].d;
3568 	if (vc->vc_sw->con_debug_leave)
3569 		ret = vc->vc_sw->con_debug_leave(vc);
3570 	return ret;
3571 }
3572 EXPORT_SYMBOL_GPL(con_debug_leave);
3573 
3574 static int do_register_con_driver(const struct consw *csw, int first, int last)
3575 {
3576 	struct module *owner = csw->owner;
3577 	struct con_driver *con_driver;
3578 	const char *desc;
3579 	int i, retval = 0;
3580 
3581 	WARN_CONSOLE_UNLOCKED();
3582 
3583 	if (!try_module_get(owner))
3584 		return -ENODEV;
3585 
3586 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3587 		con_driver = &registered_con_driver[i];
3588 
3589 		/* already registered */
3590 		if (con_driver->con == csw)
3591 			retval = -EBUSY;
3592 	}
3593 
3594 	if (retval)
3595 		goto err;
3596 
3597 	desc = csw->con_startup();
3598 
3599 	if (!desc)
3600 		goto err;
3601 
3602 	retval = -EINVAL;
3603 
3604 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3605 		con_driver = &registered_con_driver[i];
3606 
3607 		if (con_driver->con == NULL) {
3608 			con_driver->con = csw;
3609 			con_driver->desc = desc;
3610 			con_driver->node = i;
3611 			con_driver->flag = CON_DRIVER_FLAG_MODULE |
3612 			                   CON_DRIVER_FLAG_INIT;
3613 			con_driver->first = first;
3614 			con_driver->last = last;
3615 			retval = 0;
3616 			break;
3617 		}
3618 	}
3619 
3620 	if (retval)
3621 		goto err;
3622 
3623 	con_driver->dev = device_create(vtconsole_class, NULL,
3624 						MKDEV(0, con_driver->node),
3625 						NULL, "vtcon%i",
3626 						con_driver->node);
3627 
3628 	if (IS_ERR(con_driver->dev)) {
3629 		printk(KERN_WARNING "Unable to create device for %s; "
3630 		       "errno = %ld\n", con_driver->desc,
3631 		       PTR_ERR(con_driver->dev));
3632 		con_driver->dev = NULL;
3633 	} else {
3634 		vtconsole_init_device(con_driver);
3635 	}
3636 
3637 err:
3638 	module_put(owner);
3639 	return retval;
3640 }
3641 
3642 
3643 /**
3644  * do_unregister_con_driver - unregister console driver from console layer
3645  * @csw: console driver
3646  *
3647  * DESCRIPTION: All drivers that registers to the console layer must
3648  * call this function upon exit, or if the console driver is in a state
3649  * where it won't be able to handle console services, such as the
3650  * framebuffer console without loaded framebuffer drivers.
3651  *
3652  * The driver must unbind first prior to unregistration.
3653  */
3654 int do_unregister_con_driver(const struct consw *csw)
3655 {
3656 	int i;
3657 
3658 	/* cannot unregister a bound driver */
3659 	if (con_is_bound(csw))
3660 		return -EBUSY;
3661 
3662 	if (csw == conswitchp)
3663 		return -EINVAL;
3664 
3665 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3666 		struct con_driver *con_driver = &registered_con_driver[i];
3667 
3668 		if (con_driver->con == csw &&
3669 		    con_driver->flag & CON_DRIVER_FLAG_INIT) {
3670 			vtconsole_deinit_device(con_driver);
3671 			device_destroy(vtconsole_class,
3672 				       MKDEV(0, con_driver->node));
3673 			con_driver->con = NULL;
3674 			con_driver->desc = NULL;
3675 			con_driver->dev = NULL;
3676 			con_driver->node = 0;
3677 			con_driver->flag = 0;
3678 			con_driver->first = 0;
3679 			con_driver->last = 0;
3680 			return 0;
3681 		}
3682 	}
3683 
3684 	return -ENODEV;
3685 }
3686 EXPORT_SYMBOL_GPL(do_unregister_con_driver);
3687 
3688 /*
3689  *	If we support more console drivers, this function is used
3690  *	when a driver wants to take over some existing consoles
3691  *	and become default driver for newly opened ones.
3692  *
3693  *	do_take_over_console is basically a register followed by unbind
3694  */
3695 int do_take_over_console(const struct consw *csw, int first, int last, int deflt)
3696 {
3697 	int err;
3698 
3699 	err = do_register_con_driver(csw, first, last);
3700 	/*
3701 	 * If we get an busy error we still want to bind the console driver
3702 	 * and return success, as we may have unbound the console driver
3703 	 * but not unregistered it.
3704 	 */
3705 	if (err == -EBUSY)
3706 		err = 0;
3707 	if (!err)
3708 		do_bind_con_driver(csw, first, last, deflt);
3709 
3710 	return err;
3711 }
3712 EXPORT_SYMBOL_GPL(do_take_over_console);
3713 
3714 
3715 /*
3716  * give_up_console is a wrapper to unregister_con_driver. It will only
3717  * work if driver is fully unbound.
3718  */
3719 void give_up_console(const struct consw *csw)
3720 {
3721 	console_lock();
3722 	do_unregister_con_driver(csw);
3723 	console_unlock();
3724 }
3725 
3726 static int __init vtconsole_class_init(void)
3727 {
3728 	int i;
3729 
3730 	vtconsole_class = class_create(THIS_MODULE, "vtconsole");
3731 	if (IS_ERR(vtconsole_class)) {
3732 		printk(KERN_WARNING "Unable to create vt console class; "
3733 		       "errno = %ld\n", PTR_ERR(vtconsole_class));
3734 		vtconsole_class = NULL;
3735 	}
3736 
3737 	/* Add system drivers to sysfs */
3738 	for (i = 0; i < MAX_NR_CON_DRIVER; i++) {
3739 		struct con_driver *con = &registered_con_driver[i];
3740 
3741 		if (con->con && !con->dev) {
3742 			con->dev = device_create(vtconsole_class, NULL,
3743 							 MKDEV(0, con->node),
3744 							 NULL, "vtcon%i",
3745 							 con->node);
3746 
3747 			if (IS_ERR(con->dev)) {
3748 				printk(KERN_WARNING "Unable to create "
3749 				       "device for %s; errno = %ld\n",
3750 				       con->desc, PTR_ERR(con->dev));
3751 				con->dev = NULL;
3752 			} else {
3753 				vtconsole_init_device(con);
3754 			}
3755 		}
3756 	}
3757 
3758 	return 0;
3759 }
3760 postcore_initcall(vtconsole_class_init);
3761 
3762 #endif
3763 
3764 /*
3765  *	Screen blanking
3766  */
3767 
3768 static int set_vesa_blanking(char __user *p)
3769 {
3770 	unsigned int mode;
3771 
3772 	if (get_user(mode, p + 1))
3773 		return -EFAULT;
3774 
3775 	vesa_blank_mode = (mode < 4) ? mode : 0;
3776 	return 0;
3777 }
3778 
3779 void do_blank_screen(int entering_gfx)
3780 {
3781 	struct vc_data *vc = vc_cons[fg_console].d;
3782 	int i;
3783 
3784 	WARN_CONSOLE_UNLOCKED();
3785 
3786 	if (console_blanked) {
3787 		if (blank_state == blank_vesa_wait) {
3788 			blank_state = blank_off;
3789 			vc->vc_sw->con_blank(vc, vesa_blank_mode + 1, 0);
3790 		}
3791 		return;
3792 	}
3793 
3794 	/* entering graphics mode? */
3795 	if (entering_gfx) {
3796 		hide_cursor(vc);
3797 		save_screen(vc);
3798 		vc->vc_sw->con_blank(vc, -1, 1);
3799 		console_blanked = fg_console + 1;
3800 		blank_state = blank_off;
3801 		set_origin(vc);
3802 		return;
3803 	}
3804 
3805 	if (blank_state != blank_normal_wait)
3806 		return;
3807 	blank_state = blank_off;
3808 
3809 	/* don't blank graphics */
3810 	if (vc->vc_mode != KD_TEXT) {
3811 		console_blanked = fg_console + 1;
3812 		return;
3813 	}
3814 
3815 	hide_cursor(vc);
3816 	del_timer_sync(&console_timer);
3817 	blank_timer_expired = 0;
3818 
3819 	save_screen(vc);
3820 	/* In case we need to reset origin, blanking hook returns 1 */
3821 	i = vc->vc_sw->con_blank(vc, vesa_off_interval ? 1 : (vesa_blank_mode + 1), 0);
3822 	console_blanked = fg_console + 1;
3823 	if (i)
3824 		set_origin(vc);
3825 
3826 	if (console_blank_hook && console_blank_hook(1))
3827 		return;
3828 
3829 	if (vesa_off_interval && vesa_blank_mode) {
3830 		blank_state = blank_vesa_wait;
3831 		mod_timer(&console_timer, jiffies + vesa_off_interval);
3832 	}
3833 	vt_event_post(VT_EVENT_BLANK, vc->vc_num, vc->vc_num);
3834 }
3835 EXPORT_SYMBOL(do_blank_screen);
3836 
3837 /*
3838  * Called by timer as well as from vt_console_driver
3839  */
3840 void do_unblank_screen(int leaving_gfx)
3841 {
3842 	struct vc_data *vc;
3843 
3844 	/* This should now always be called from a "sane" (read: can schedule)
3845 	 * context for the sake of the low level drivers, except in the special
3846 	 * case of oops_in_progress
3847 	 */
3848 	if (!oops_in_progress)
3849 		might_sleep();
3850 
3851 	WARN_CONSOLE_UNLOCKED();
3852 
3853 	ignore_poke = 0;
3854 	if (!console_blanked)
3855 		return;
3856 	if (!vc_cons_allocated(fg_console)) {
3857 		/* impossible */
3858 		pr_warn("unblank_screen: tty %d not allocated ??\n",
3859 			fg_console + 1);
3860 		return;
3861 	}
3862 	vc = vc_cons[fg_console].d;
3863 	/* Try to unblank in oops case too */
3864 	if (vc->vc_mode != KD_TEXT && !vt_force_oops_output(vc))
3865 		return; /* but leave console_blanked != 0 */
3866 
3867 	if (blankinterval) {
3868 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3869 		blank_state = blank_normal_wait;
3870 	}
3871 
3872 	console_blanked = 0;
3873 	if (vc->vc_sw->con_blank(vc, 0, leaving_gfx) || vt_force_oops_output(vc))
3874 		/* Low-level driver cannot restore -> do it ourselves */
3875 		update_screen(vc);
3876 	if (console_blank_hook)
3877 		console_blank_hook(0);
3878 	set_palette(vc);
3879 	set_cursor(vc);
3880 	vt_event_post(VT_EVENT_UNBLANK, vc->vc_num, vc->vc_num);
3881 }
3882 EXPORT_SYMBOL(do_unblank_screen);
3883 
3884 /*
3885  * This is called by the outside world to cause a forced unblank, mostly for
3886  * oopses. Currently, I just call do_unblank_screen(0), but we could eventually
3887  * call it with 1 as an argument and so force a mode restore... that may kill
3888  * X or at least garbage the screen but would also make the Oops visible...
3889  */
3890 void unblank_screen(void)
3891 {
3892 	do_unblank_screen(0);
3893 }
3894 
3895 /*
3896  * We defer the timer blanking to work queue so it can take the console mutex
3897  * (console operations can still happen at irq time, but only from printk which
3898  * has the console mutex. Not perfect yet, but better than no locking
3899  */
3900 static void blank_screen_t(unsigned long dummy)
3901 {
3902 	if (unlikely(!keventd_up())) {
3903 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3904 		return;
3905 	}
3906 	blank_timer_expired = 1;
3907 	schedule_work(&console_work);
3908 }
3909 
3910 void poke_blanked_console(void)
3911 {
3912 	WARN_CONSOLE_UNLOCKED();
3913 
3914 	/* Add this so we quickly catch whoever might call us in a non
3915 	 * safe context. Nowadays, unblank_screen() isn't to be called in
3916 	 * atomic contexts and is allowed to schedule (with the special case
3917 	 * of oops_in_progress, but that isn't of any concern for this
3918 	 * function. --BenH.
3919 	 */
3920 	might_sleep();
3921 
3922 	/* This isn't perfectly race free, but a race here would be mostly harmless,
3923 	 * at worse, we'll do a spurrious blank and it's unlikely
3924 	 */
3925 	del_timer(&console_timer);
3926 	blank_timer_expired = 0;
3927 
3928 	if (ignore_poke || !vc_cons[fg_console].d || vc_cons[fg_console].d->vc_mode == KD_GRAPHICS)
3929 		return;
3930 	if (console_blanked)
3931 		unblank_screen();
3932 	else if (blankinterval) {
3933 		mod_timer(&console_timer, jiffies + (blankinterval * HZ));
3934 		blank_state = blank_normal_wait;
3935 	}
3936 }
3937 
3938 /*
3939  *	Palettes
3940  */
3941 
3942 static void set_palette(struct vc_data *vc)
3943 {
3944 	WARN_CONSOLE_UNLOCKED();
3945 
3946 	if (vc->vc_mode != KD_GRAPHICS)
3947 		vc->vc_sw->con_set_palette(vc, color_table);
3948 }
3949 
3950 /*
3951  * Load palette into the DAC registers. arg points to a colour
3952  * map, 3 bytes per colour, 16 colours, range from 0 to 255.
3953  */
3954 
3955 int con_set_cmap(unsigned char __user *arg)
3956 {
3957 	int i, j, k;
3958 	unsigned char colormap[3*16];
3959 
3960 	if (copy_from_user(colormap, arg, sizeof(colormap)))
3961 		return -EFAULT;
3962 
3963 	console_lock();
3964 	for (i = k = 0; i < 16; i++) {
3965 		default_red[i] = colormap[k++];
3966 		default_grn[i] = colormap[k++];
3967 		default_blu[i] = colormap[k++];
3968 	}
3969 	for (i = 0; i < MAX_NR_CONSOLES; i++) {
3970 		if (!vc_cons_allocated(i))
3971 			continue;
3972 		for (j = k = 0; j < 16; j++) {
3973 			vc_cons[i].d->vc_palette[k++] = default_red[j];
3974 			vc_cons[i].d->vc_palette[k++] = default_grn[j];
3975 			vc_cons[i].d->vc_palette[k++] = default_blu[j];
3976 		}
3977 		set_palette(vc_cons[i].d);
3978 	}
3979 	console_unlock();
3980 
3981 	return 0;
3982 }
3983 
3984 int con_get_cmap(unsigned char __user *arg)
3985 {
3986 	int i, k;
3987 	unsigned char colormap[3*16];
3988 
3989 	console_lock();
3990 	for (i = k = 0; i < 16; i++) {
3991 		colormap[k++] = default_red[i];
3992 		colormap[k++] = default_grn[i];
3993 		colormap[k++] = default_blu[i];
3994 	}
3995 	console_unlock();
3996 
3997 	if (copy_to_user(arg, colormap, sizeof(colormap)))
3998 		return -EFAULT;
3999 
4000 	return 0;
4001 }
4002 
4003 void reset_palette(struct vc_data *vc)
4004 {
4005 	int j, k;
4006 	for (j=k=0; j<16; j++) {
4007 		vc->vc_palette[k++] = default_red[j];
4008 		vc->vc_palette[k++] = default_grn[j];
4009 		vc->vc_palette[k++] = default_blu[j];
4010 	}
4011 	set_palette(vc);
4012 }
4013 
4014 /*
4015  *  Font switching
4016  *
4017  *  Currently we only support fonts up to 32 pixels wide, at a maximum height
4018  *  of 32 pixels. Userspace fontdata is stored with 32 bytes (shorts/ints,
4019  *  depending on width) reserved for each character which is kinda wasty, but
4020  *  this is done in order to maintain compatibility with the EGA/VGA fonts. It
4021  *  is up to the actual low-level console-driver convert data into its favorite
4022  *  format (maybe we should add a `fontoffset' field to the `display'
4023  *  structure so we won't have to convert the fontdata all the time.
4024  *  /Jes
4025  */
4026 
4027 #define max_font_size 65536
4028 
4029 static int con_font_get(struct vc_data *vc, struct console_font_op *op)
4030 {
4031 	struct console_font font;
4032 	int rc = -EINVAL;
4033 	int c;
4034 
4035 	if (op->data) {
4036 		font.data = kmalloc(max_font_size, GFP_KERNEL);
4037 		if (!font.data)
4038 			return -ENOMEM;
4039 	} else
4040 		font.data = NULL;
4041 
4042 	console_lock();
4043 	if (vc->vc_mode != KD_TEXT)
4044 		rc = -EINVAL;
4045 	else if (vc->vc_sw->con_font_get)
4046 		rc = vc->vc_sw->con_font_get(vc, &font);
4047 	else
4048 		rc = -ENOSYS;
4049 	console_unlock();
4050 
4051 	if (rc)
4052 		goto out;
4053 
4054 	c = (font.width+7)/8 * 32 * font.charcount;
4055 
4056 	if (op->data && font.charcount > op->charcount)
4057 		rc = -ENOSPC;
4058 	if (!(op->flags & KD_FONT_FLAG_OLD)) {
4059 		if (font.width > op->width || font.height > op->height)
4060 			rc = -ENOSPC;
4061 	} else {
4062 		if (font.width != 8)
4063 			rc = -EIO;
4064 		else if ((op->height && font.height > op->height) ||
4065 			 font.height > 32)
4066 			rc = -ENOSPC;
4067 	}
4068 	if (rc)
4069 		goto out;
4070 
4071 	op->height = font.height;
4072 	op->width = font.width;
4073 	op->charcount = font.charcount;
4074 
4075 	if (op->data && copy_to_user(op->data, font.data, c))
4076 		rc = -EFAULT;
4077 
4078 out:
4079 	kfree(font.data);
4080 	return rc;
4081 }
4082 
4083 static int con_font_set(struct vc_data *vc, struct console_font_op *op)
4084 {
4085 	struct console_font font;
4086 	int rc = -EINVAL;
4087 	int size;
4088 
4089 	if (vc->vc_mode != KD_TEXT)
4090 		return -EINVAL;
4091 	if (!op->data)
4092 		return -EINVAL;
4093 	if (op->charcount > 512)
4094 		return -EINVAL;
4095 	if (!op->height) {		/* Need to guess font height [compat] */
4096 		int h, i;
4097 		u8 __user *charmap = op->data;
4098 		u8 tmp;
4099 
4100 		/* If from KDFONTOP ioctl, don't allow things which can be done in userland,
4101 		   so that we can get rid of this soon */
4102 		if (!(op->flags & KD_FONT_FLAG_OLD))
4103 			return -EINVAL;
4104 		for (h = 32; h > 0; h--)
4105 			for (i = 0; i < op->charcount; i++) {
4106 				if (get_user(tmp, &charmap[32*i+h-1]))
4107 					return -EFAULT;
4108 				if (tmp)
4109 					goto nonzero;
4110 			}
4111 		return -EINVAL;
4112 	nonzero:
4113 		op->height = h;
4114 	}
4115 	if (op->width <= 0 || op->width > 32 || op->height > 32)
4116 		return -EINVAL;
4117 	size = (op->width+7)/8 * 32 * op->charcount;
4118 	if (size > max_font_size)
4119 		return -ENOSPC;
4120 	font.charcount = op->charcount;
4121 	font.height = op->height;
4122 	font.width = op->width;
4123 	font.data = memdup_user(op->data, size);
4124 	if (IS_ERR(font.data))
4125 		return PTR_ERR(font.data);
4126 	console_lock();
4127 	if (vc->vc_mode != KD_TEXT)
4128 		rc = -EINVAL;
4129 	else if (vc->vc_sw->con_font_set)
4130 		rc = vc->vc_sw->con_font_set(vc, &font, op->flags);
4131 	else
4132 		rc = -ENOSYS;
4133 	console_unlock();
4134 	kfree(font.data);
4135 	return rc;
4136 }
4137 
4138 static int con_font_default(struct vc_data *vc, struct console_font_op *op)
4139 {
4140 	struct console_font font = {.width = op->width, .height = op->height};
4141 	char name[MAX_FONT_NAME];
4142 	char *s = name;
4143 	int rc;
4144 
4145 
4146 	if (!op->data)
4147 		s = NULL;
4148 	else if (strncpy_from_user(name, op->data, MAX_FONT_NAME - 1) < 0)
4149 		return -EFAULT;
4150 	else
4151 		name[MAX_FONT_NAME - 1] = 0;
4152 
4153 	console_lock();
4154 	if (vc->vc_mode != KD_TEXT) {
4155 		console_unlock();
4156 		return -EINVAL;
4157 	}
4158 	if (vc->vc_sw->con_font_default)
4159 		rc = vc->vc_sw->con_font_default(vc, &font, s);
4160 	else
4161 		rc = -ENOSYS;
4162 	console_unlock();
4163 	if (!rc) {
4164 		op->width = font.width;
4165 		op->height = font.height;
4166 	}
4167 	return rc;
4168 }
4169 
4170 static int con_font_copy(struct vc_data *vc, struct console_font_op *op)
4171 {
4172 	int con = op->height;
4173 	int rc;
4174 
4175 
4176 	console_lock();
4177 	if (vc->vc_mode != KD_TEXT)
4178 		rc = -EINVAL;
4179 	else if (!vc->vc_sw->con_font_copy)
4180 		rc = -ENOSYS;
4181 	else if (con < 0 || !vc_cons_allocated(con))
4182 		rc = -ENOTTY;
4183 	else if (con == vc->vc_num)	/* nothing to do */
4184 		rc = 0;
4185 	else
4186 		rc = vc->vc_sw->con_font_copy(vc, con);
4187 	console_unlock();
4188 	return rc;
4189 }
4190 
4191 int con_font_op(struct vc_data *vc, struct console_font_op *op)
4192 {
4193 	switch (op->op) {
4194 	case KD_FONT_OP_SET:
4195 		return con_font_set(vc, op);
4196 	case KD_FONT_OP_GET:
4197 		return con_font_get(vc, op);
4198 	case KD_FONT_OP_SET_DEFAULT:
4199 		return con_font_default(vc, op);
4200 	case KD_FONT_OP_COPY:
4201 		return con_font_copy(vc, op);
4202 	}
4203 	return -ENOSYS;
4204 }
4205 
4206 /*
4207  *	Interface exported to selection and vcs.
4208  */
4209 
4210 /* used by selection */
4211 u16 screen_glyph(struct vc_data *vc, int offset)
4212 {
4213 	u16 w = scr_readw(screenpos(vc, offset, 1));
4214 	u16 c = w & 0xff;
4215 
4216 	if (w & vc->vc_hi_font_mask)
4217 		c |= 0x100;
4218 	return c;
4219 }
4220 EXPORT_SYMBOL_GPL(screen_glyph);
4221 
4222 /* used by vcs - note the word offset */
4223 unsigned short *screen_pos(struct vc_data *vc, int w_offset, int viewed)
4224 {
4225 	return screenpos(vc, 2 * w_offset, viewed);
4226 }
4227 
4228 void getconsxy(struct vc_data *vc, unsigned char *p)
4229 {
4230 	p[0] = vc->vc_x;
4231 	p[1] = vc->vc_y;
4232 }
4233 
4234 void putconsxy(struct vc_data *vc, unsigned char *p)
4235 {
4236 	hide_cursor(vc);
4237 	gotoxy(vc, p[0], p[1]);
4238 	set_cursor(vc);
4239 }
4240 
4241 u16 vcs_scr_readw(struct vc_data *vc, const u16 *org)
4242 {
4243 	if ((unsigned long)org == vc->vc_pos && softcursor_original != -1)
4244 		return softcursor_original;
4245 	return scr_readw(org);
4246 }
4247 
4248 void vcs_scr_writew(struct vc_data *vc, u16 val, u16 *org)
4249 {
4250 	scr_writew(val, org);
4251 	if ((unsigned long)org == vc->vc_pos) {
4252 		softcursor_original = -1;
4253 		add_softcursor(vc);
4254 	}
4255 }
4256 
4257 void vcs_scr_updated(struct vc_data *vc)
4258 {
4259 	notify_update(vc);
4260 }
4261 
4262 /*
4263  *	Visible symbols for modules
4264  */
4265 
4266 EXPORT_SYMBOL(color_table);
4267 EXPORT_SYMBOL(default_red);
4268 EXPORT_SYMBOL(default_grn);
4269 EXPORT_SYMBOL(default_blu);
4270 EXPORT_SYMBOL(update_region);
4271 EXPORT_SYMBOL(redraw_screen);
4272 EXPORT_SYMBOL(vc_resize);
4273 EXPORT_SYMBOL(fg_console);
4274 EXPORT_SYMBOL(console_blank_hook);
4275 EXPORT_SYMBOL(console_blanked);
4276 EXPORT_SYMBOL(vc_cons);
4277 EXPORT_SYMBOL(global_cursor_default);
4278 #ifndef VT_SINGLE_DRIVER
4279 EXPORT_SYMBOL(give_up_console);
4280 #endif
4281