vt: fix broken display when running aptitude
[sfrench/cifs-2.6.git] / drivers / tty / vt / vt.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Copyright (C) 1991, 1992  Linus Torvalds
4  */
5
6 /*
7  * Hopefully this will be a rather complete VT102 implementation.
8  *
9  * Beeping thanks to John T Kohl.
10  *
11  * Virtual Consoles, Screen Blanking, Screen Dumping, Color, Graphics
12  *   Chars, and VT100 enhancements by Peter MacDonald.
13  *
14  * Copy and paste function by Andrew Haylett,
15  *   some enhancements by Alessandro Rubini.
16  *
17  * Code to check for different video-cards mostly by Galen Hunt,
18  * <g-hunt@ee.utah.edu>
19  *
20  * Rudimentary ISO 10646/Unicode/UTF-8 character set support by
21  * Markus Kuhn, <mskuhn@immd4.informatik.uni-erlangen.de>.
22  *
23  * Dynamic allocation of consoles, aeb@cwi.nl, May 1994
24  * Resizing of consoles, aeb, 940926
25  *
26  * Code for xterm like mouse click reporting by Peter Orbaek 20-Jul-94
27  * <poe@daimi.aau.dk>
28  *
29  * User-defined bell sound, new setterm control sequences and printk
30  * redirection by Martin Mares <mj@k332.feld.cvut.cz> 19-Nov-95
31  *
32  * APM screenblank bug fixed Takashi Manabe <manabe@roy.dsl.tutics.tut.jp>
33  *
34  * Merge with the abstract console driver by Geert Uytterhoeven
35  * <geert@linux-m68k.org>, Jan 1997.
36  *
37  *   Original m68k console driver modifications by
38  *
39  *     - Arno Griffioen <arno@usn.nl>
40  *     - David Carter <carter@cs.bris.ac.uk>
41  * 
42  *   The abstract console driver provides a generic interface for a text
43  *   console. It supports VGA text mode, frame buffer based graphical consoles
44  *   and special graphics processors that are only accessible through some
45  *   registers (e.g. a TMS340x0 GSP).
46  *
47  *   The interface to the hardware is specified using a special structure
48  *   (struct consw) which contains function pointers to console operations
49  *   (see <linux/console.h> for more information).
50  *
51  * Support for changeable cursor shape
52  * by Pavel Machek <pavel@atrey.karlin.mff.cuni.cz>, August 1997
53  *
54  * Ported to i386 and con_scrolldelta fixed
55  * by Emmanuel Marty <core@ggi-project.org>, April 1998
56  *
57  * Resurrected character buffers in videoram plus lots of other trickery
58  * by Martin Mares <mj@atrey.karlin.mff.cuni.cz>, July 1998
59  *
60  * Removed old-style timers, introduced console_timer, made timer
61  * deletion SMP-safe.  17Jun00, Andrew Morton
62  *
63  * Removed console_lock, enabled interrupts across all console operations
64  * 13 March 2001, Andrew Morton
65  *
66  * Fixed UTF-8 mode so alternate charset modes always work according
67  * to control sequences interpreted in do_con_trol function
68  * preserving backward VT100 semigraphics compatibility,
69  * malformed UTF sequences represented as sequences of replacement glyphs,
70  * original codes or '?' as a last resort if replacement glyph is undefined
71  * by Adam Tla/lka <atlka@pg.gda.pl>, Aug 2006
72  */
73
74 #include <linux/module.h>
75 #include <linux/types.h>
76 #include <linux/sched/signal.h>
77 #include <linux/tty.h>
78 #include <linux/tty_flip.h>
79 #include <linux/kernel.h>
80 #include <linux/string.h>
81 #include <linux/errno.h>
82 #include <linux/kd.h>
83 #include <linux/slab.h>
84 #include <linux/major.h>
85 #include <linux/mm.h>
86 #include <linux/console.h>
87 #include <linux/init.h>
88 #include <linux/mutex.h>
89 #include <linux/vt_kern.h>
90 #include <linux/selection.h>
91 #include <linux/tiocl.h>
92 #include <linux/kbd_kern.h>
93 #include <linux/consolemap.h>
94 #include <linux/timer.h>
95 #include <linux/interrupt.h>
96 #include <linux/workqueue.h>
97 #include <linux/pm.h>
98 #include <linux/font.h>
99 #include <linux/bitops.h>
100 #include <linux/notifier.h>
101 #include <linux/device.h>
102 #include <linux/io.h>
103 #include <linux/uaccess.h>
104 #include <linux/kdb.h>
105 #include <linux/ctype.h>
106 #include <linux/bsearch.h>
107 #include <linux/gcd.h>
108
109 #define MAX_NR_CON_DRIVER 16
110
111 #define CON_DRIVER_FLAG_MODULE 1
112 #define CON_DRIVER_FLAG_INIT   2
113 #define CON_DRIVER_FLAG_ATTR   4
114 #define CON_DRIVER_FLAG_ZOMBIE 8
115
116 struct con_driver {
117         const struct consw *con;
118         const char *desc;
119         struct device *dev;
120         int node;
121         int first;
122         int last;
123         int flag;
124 };
125
126 static struct con_driver registered_con_driver[MAX_NR_CON_DRIVER];
127 const struct consw *conswitchp;
128
129 /* A bitmap for codes <32. A bit of 1 indicates that the code
130  * corresponding to that bit number invokes some special action
131  * (such as cursor movement) and should not be displayed as a
132  * glyph unless the disp_ctrl mode is explicitly enabled.
133  */
134 #define CTRL_ACTION 0x0d00ff81
135 #define CTRL_ALWAYS 0x0800f501  /* Cannot be overridden by disp_ctrl */
136
137 /*
138  * Here is the default bell parameters: 750HZ, 1/8th of a second
139  */
140 #define DEFAULT_BELL_PITCH      750
141 #define DEFAULT_BELL_DURATION   (HZ/8)
142 #define DEFAULT_CURSOR_BLINK_MS 200
143
144 struct vc vc_cons [MAX_NR_CONSOLES];
145
146 #ifndef VT_SINGLE_DRIVER
147 static const struct consw *con_driver_map[MAX_NR_CONSOLES];
148 #endif
149
150 static int con_open(struct tty_struct *, struct file *);
151 static void vc_init(struct vc_data *vc, unsigned int rows,
152                     unsigned int cols, int do_clear);
153 static void gotoxy(struct vc_data *vc, int new_x, int new_y);
154 static void save_cur(struct vc_data *vc);
155 static void reset_terminal(struct vc_data *vc, int do_clear);
156 static void con_flush_chars(struct tty_struct *tty);
157 static int set_vesa_blanking(char __user *p);
158 static void set_cursor(struct vc_data *vc);
159 static void hide_cursor(struct vc_data *vc);
160 static void console_callback(struct work_struct *ignored);
161 static void con_driver_unregister_callback(struct work_struct *ignored);
162 static void blank_screen_t(struct timer_list *unused);
163 static void set_palette(struct vc_data *vc);
164
165 #define vt_get_kmsg_redirect() vt_kmsg_redirect(-1)
166
167 static int printable;           /* Is console ready for printing? */
168 int default_utf8 = true;
169 module_param(default_utf8, int, S_IRUGO | S_IWUSR);
170 int global_cursor_default = -1;
171 module_param(global_cursor_default, int, S_IRUGO | S_IWUSR);
172
173 static int cur_default = CUR_DEFAULT;
174 module_param(cur_default, int, S_IRUGO | S_IWUSR);
175
176 /*
177  * ignore_poke: don't unblank the screen when things are typed.  This is
178  * mainly for the privacy of braille terminal users.
179  */
180 static int ignore_poke;
181
182 int do_poke_blanked_console;
183 int console_blanked;
184
185 static int vesa_blank_mode; /* 0:none 1:suspendV 2:suspendH 3:powerdown */
186 static int vesa_off_interval;
187 static int blankinterval;
188 core_param(consoleblank, blankinterval, int, 0444);
189
190 static DECLARE_WORK(console_work, console_callback);
191 static DECLARE_WORK(con_driver_unregister_work, con_driver_unregister_callback);
192
193 /*
194  * fg_console is the current virtual console,
195  * last_console is the last used one,
196  * want_console is the console we want to switch to,
197  * saved_* variants are for save/restore around kernel debugger enter/leave
198  */
199 int fg_console;
200 int last_console;
201 int want_console = -1;
202 static int saved_fg_console;
203 static int saved_last_console;
204 static int saved_want_console;
205 static int saved_vc_mode;
206 static int saved_console_blanked;
207
208 /*
209  * For each existing display, we have a pointer to console currently visible
210  * on that display, allowing consoles other than fg_console to be refreshed
211  * appropriately. Unless the low-level driver supplies its own display_fg
212  * variable, we use this one for the "master display".
213  */
214 static struct vc_data *master_display_fg;
215
216 /*
217  * Unfortunately, we need to delay tty echo when we're currently writing to the
218  * console since the code is (and always was) not re-entrant, so we schedule
219  * all flip requests to process context with schedule-task() and run it from
220  * console_callback().
221  */
222
223 /*
224  * For the same reason, we defer scrollback to the console callback.
225  */
226 static int scrollback_delta;
227
228 /*
229  * Hook so that the power management routines can (un)blank
230  * the console on our behalf.
231  */
232 int (*console_blank_hook)(int);
233
234 static DEFINE_TIMER(console_timer, blank_screen_t);
235 static int blank_state;
236 static int blank_timer_expired;
237 enum {
238         blank_off = 0,
239         blank_normal_wait,
240         blank_vesa_wait,
241 };
242
243 /*
244  * /sys/class/tty/tty0/
245  *
246  * the attribute 'active' contains the name of the current vc
247  * console and it supports poll() to detect vc switches
248  */
249 static struct device *tty0dev;
250
251 /*
252  * Notifier list for console events.
253  */
254 static ATOMIC_NOTIFIER_HEAD(vt_notifier_list);
255
256 int register_vt_notifier(struct notifier_block *nb)
257 {
258         return atomic_notifier_chain_register(&vt_notifier_list, nb);
259 }
260 EXPORT_SYMBOL_GPL(register_vt_notifier);
261
262 int unregister_vt_notifier(struct notifier_block *nb)
263 {
264         return atomic_notifier_chain_unregister(&vt_notifier_list, nb);
265 }
266 EXPORT_SYMBOL_GPL(unregister_vt_notifier);
267
268 static void notify_write(struct vc_data *vc, unsigned int unicode)
269 {
270         struct vt_notifier_param param = { .vc = vc, .c = unicode };
271         atomic_notifier_call_chain(&vt_notifier_list, VT_WRITE, &param);
272 }
273
274 static void notify_update(struct vc_data *vc)
275 {
276         struct vt_notifier_param param = { .vc = vc };
277         atomic_notifier_call_chain(&vt_notifier_list, VT_UPDATE, &param);
278 }
279 /*
280  *      Low-Level Functions
281  */
282
283 static inline bool con_is_fg(const struct vc_data *vc)
284 {
285         return vc->vc_num == fg_console;
286 }
287
288 static inline bool con_should_update(const struct vc_data *vc)
289 {
290         return con_is_visible(vc) && !console_blanked;
291 }
292
293 static inline unsigned short *screenpos(struct vc_data *vc, int offset, int viewed)
294 {
295         unsigned short *p;
296         
297         if (!viewed)
298                 p = (unsigned short *)(vc->vc_origin + offset);
299         else if (!vc->vc_sw->con_screen_pos)
300                 p = (unsigned short *)(vc->vc_visible_origin + offset);
301         else
302                 p = vc->vc_sw->con_screen_pos(vc, offset);
303         return p;
304 }
305
306 /* Called  from the keyboard irq path.. */
307 static inline void scrolldelta(int lines)
308 {
309         /* FIXME */
310         /* scrolldelta needs some kind of consistency lock, but the BKL was
311            and still is not protecting versus the scheduled back end */
312         scrollback_delta += lines;
313         schedule_console_callback();
314 }
315
316 void schedule_console_callback(void)
317 {
318         schedule_work(&console_work);
319 }
320
321 /*
322  * Code to manage unicode-based screen buffers
323  */
324
325 #ifdef NO_VC_UNI_SCREEN
326 /* this disables and optimizes related code away at compile time */
327 #define get_vc_uniscr(vc) NULL
328 #else
329 #define get_vc_uniscr(vc) vc->vc_uni_screen
330 #endif
331
332 #define VC_UNI_SCREEN_DEBUG 0
333
334 typedef uint32_t char32_t;
335
336 /*
337  * Our screen buffer is preceded by an array of line pointers so that
338  * scrolling only implies some pointer shuffling.
339  */
340 struct uni_screen {
341         char32_t *lines[0];
342 };
343
344 static struct uni_screen *vc_uniscr_alloc(unsigned int cols, unsigned int rows)
345 {
346         struct uni_screen *uniscr;
347         void *p;
348         unsigned int memsize, i;
349
350         /* allocate everything in one go */
351         memsize = cols * rows * sizeof(char32_t);
352         memsize += rows * sizeof(char32_t *);
353         p = kmalloc(memsize, GFP_KERNEL);
354         if (!p)
355                 return NULL;
356
357         /* initial line pointers */
358         uniscr = p;
359         p = uniscr->lines + rows;
360         for (i = 0; i < rows; i++) {
361                 uniscr->lines[i] = p;
362                 p += cols * sizeof(char32_t);
363         }
364         return uniscr;
365 }
366
367 static void vc_uniscr_set(struct vc_data *vc, struct uni_screen *new_uniscr)
368 {
369         kfree(vc->vc_uni_screen);
370         vc->vc_uni_screen = new_uniscr;
371 }
372
373 static void vc_uniscr_putc(struct vc_data *vc, char32_t uc)
374 {
375         struct uni_screen *uniscr = get_vc_uniscr(vc);
376
377         if (uniscr)
378                 uniscr->lines[vc->vc_y][vc->vc_x] = uc;
379 }
380
381 static void vc_uniscr_insert(struct vc_data *vc, unsigned int nr)
382 {
383         struct uni_screen *uniscr = get_vc_uniscr(vc);
384
385         if (uniscr) {
386                 char32_t *ln = uniscr->lines[vc->vc_y];
387                 unsigned int x = vc->vc_x, cols = vc->vc_cols;
388
389                 memmove(&ln[x + nr], &ln[x], (cols - x - nr) * sizeof(*ln));
390                 memset32(&ln[x], ' ', nr);
391         }
392 }
393
394 static void vc_uniscr_delete(struct vc_data *vc, unsigned int nr)
395 {
396         struct uni_screen *uniscr = get_vc_uniscr(vc);
397
398         if (uniscr) {
399                 char32_t *ln = uniscr->lines[vc->vc_y];
400                 unsigned int x = vc->vc_x, cols = vc->vc_cols;
401
402                 memcpy(&ln[x], &ln[x + nr], (cols - x - nr) * sizeof(*ln));
403                 memset32(&ln[cols - nr], ' ', nr);
404         }
405 }
406
407 static void vc_uniscr_clear_line(struct vc_data *vc, unsigned int x,
408                                  unsigned int nr)
409 {
410         struct uni_screen *uniscr = get_vc_uniscr(vc);
411
412         if (uniscr) {
413                 char32_t *ln = uniscr->lines[vc->vc_y];
414
415                 memset32(&ln[x], ' ', nr);
416         }
417 }
418
419 static void vc_uniscr_clear_lines(struct vc_data *vc, unsigned int y,
420                                   unsigned int nr)
421 {
422         struct uni_screen *uniscr = get_vc_uniscr(vc);
423
424         if (uniscr) {
425                 unsigned int cols = vc->vc_cols;
426
427                 while (nr--)
428                         memset32(uniscr->lines[y++], ' ', cols);
429         }
430 }
431
432 static void vc_uniscr_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
433                              enum con_scroll dir, unsigned int nr)
434 {
435         struct uni_screen *uniscr = get_vc_uniscr(vc);
436
437         if (uniscr) {
438                 unsigned int i, j, k, sz, d, clear;
439
440                 sz = b - t;
441                 clear = b - nr;
442                 d = nr;
443                 if (dir == SM_DOWN) {
444                         clear = t;
445                         d = sz - nr;
446                 }
447                 for (i = 0; i < gcd(d, sz); i++) {
448                         char32_t *tmp = uniscr->lines[t + i];
449                         j = i;
450                         while (1) {
451                                 k = j + d;
452                                 if (k >= sz)
453                                         k -= sz;
454                                 if (k == i)
455                                         break;
456                                 uniscr->lines[t + j] = uniscr->lines[t + k];
457                                 j = k;
458                         }
459                         uniscr->lines[t + j] = tmp;
460                 }
461                 vc_uniscr_clear_lines(vc, clear, nr);
462         }
463 }
464
465 static void vc_uniscr_copy_area(struct uni_screen *dst,
466                                 unsigned int dst_cols,
467                                 unsigned int dst_rows,
468                                 struct uni_screen *src,
469                                 unsigned int src_cols,
470                                 unsigned int src_top_row,
471                                 unsigned int src_bot_row)
472 {
473         unsigned int dst_row = 0;
474
475         if (!dst)
476                 return;
477
478         while (src_top_row < src_bot_row) {
479                 char32_t *src_line = src->lines[src_top_row];
480                 char32_t *dst_line = dst->lines[dst_row];
481
482                 memcpy(dst_line, src_line, src_cols * sizeof(char32_t));
483                 if (dst_cols - src_cols)
484                         memset32(dst_line + src_cols, ' ', dst_cols - src_cols);
485                 src_top_row++;
486                 dst_row++;
487         }
488         while (dst_row < dst_rows) {
489                 char32_t *dst_line = dst->lines[dst_row];
490
491                 memset32(dst_line, ' ', dst_cols);
492                 dst_row++;
493         }
494 }
495
496 /*
497  * Called from vcs_read() to make sure unicode screen retrieval is possible.
498  * This will initialize the unicode screen buffer if not already done.
499  * This returns 0 if OK, or a negative error code otherwise.
500  * In particular, -ENODATA is returned if the console is not in UTF-8 mode.
501  */
502 int vc_uniscr_check(struct vc_data *vc)
503 {
504         struct uni_screen *uniscr;
505         unsigned short *p;
506         int x, y, mask;
507
508         if (__is_defined(NO_VC_UNI_SCREEN))
509                 return -EOPNOTSUPP;
510
511         WARN_CONSOLE_UNLOCKED();
512
513         if (!vc->vc_utf)
514                 return -ENODATA;
515
516         if (vc->vc_uni_screen)
517                 return 0;
518
519         uniscr = vc_uniscr_alloc(vc->vc_cols, vc->vc_rows);
520         if (!uniscr)
521                 return -ENOMEM;
522
523         /*
524          * Let's populate it initially with (imperfect) reverse translation.
525          * This is the next best thing we can do short of having it enabled
526          * from the start even when no users rely on this functionality. True
527          * unicode content will be available after a complete screen refresh.
528          */
529         p = (unsigned short *)vc->vc_origin;
530         mask = vc->vc_hi_font_mask | 0xff;
531         for (y = 0; y < vc->vc_rows; y++) {
532                 char32_t *line = uniscr->lines[y];
533                 for (x = 0; x < vc->vc_cols; x++) {
534                         u16 glyph = scr_readw(p++) & mask;
535                         line[x] = inverse_translate(vc, glyph, true);
536                 }
537         }
538
539         vc->vc_uni_screen = uniscr;
540         return 0;
541 }
542
543 /*
544  * Called from vcs_read() to get the unicode data from the screen.
545  * This must be preceded by a successful call to vc_uniscr_check() once
546  * the console lock has been taken.
547  */
548 void vc_uniscr_copy_line(struct vc_data *vc, void *dest, int viewed,
549                          unsigned int row, unsigned int col, unsigned int nr)
550 {
551         struct uni_screen *uniscr = get_vc_uniscr(vc);
552         int offset = row * vc->vc_size_row + col * 2;
553         unsigned long pos;
554
555         BUG_ON(!uniscr);
556
557         pos = (unsigned long)screenpos(vc, offset, viewed);
558         if (pos >= vc->vc_origin && pos < vc->vc_scr_end) {
559                 /*
560                  * Desired position falls in the main screen buffer.
561                  * However the actual row/col might be different if
562                  * scrollback is active.
563                  */
564                 row = (pos - vc->vc_origin) / vc->vc_size_row;
565                 col = ((pos - vc->vc_origin) % vc->vc_size_row) / 2;
566                 memcpy(dest, &uniscr->lines[row][col], nr * sizeof(char32_t));
567         } else {
568                 /*
569                  * Scrollback is active. For now let's simply backtranslate
570                  * the screen glyphs until the unicode screen buffer does
571                  * synchronize with console display drivers for a scrollback
572                  * buffer of its own.
573                  */
574                 u16 *p = (u16 *)pos;
575                 int mask = vc->vc_hi_font_mask | 0xff;
576                 char32_t *uni_buf = dest;
577                 while (nr--) {
578                         u16 glyph = scr_readw(p++) & mask;
579                         *uni_buf++ = inverse_translate(vc, glyph, true);
580                 }
581         }
582 }
583
584 /* this is for validation and debugging only */
585 static void vc_uniscr_debug_check(struct vc_data *vc)
586 {
587         struct uni_screen *uniscr = get_vc_uniscr(vc);
588         unsigned short *p;
589         int x, y, mask;
590
591         if (!VC_UNI_SCREEN_DEBUG || !uniscr)
592                 return;
593
594         WARN_CONSOLE_UNLOCKED();
595
596         /*
597          * Make sure our unicode screen translates into the same glyphs
598          * as the actual screen. This is brutal indeed.
599          */
600         p = (unsigned short *)vc->vc_origin;
601         mask = vc->vc_hi_font_mask | 0xff;
602         for (y = 0; y < vc->vc_rows; y++) {
603                 char32_t *line = uniscr->lines[y];
604                 for (x = 0; x < vc->vc_cols; x++) {
605                         u16 glyph = scr_readw(p++) & mask;
606                         char32_t uc = line[x];
607                         int tc = conv_uni_to_pc(vc, uc);
608                         if (tc == -4)
609                                 tc = conv_uni_to_pc(vc, 0xfffd);
610                         if (tc == -4)
611                                 tc = conv_uni_to_pc(vc, '?');
612                         if (tc != glyph)
613                                 pr_err_ratelimited(
614                                         "%s: mismatch at %d,%d: glyph=%#x tc=%#x\n",
615                                         __func__, x, y, glyph, tc);
616                 }
617         }
618 }
619
620
621 static void con_scroll(struct vc_data *vc, unsigned int t, unsigned int b,
622                 enum con_scroll dir, unsigned int nr)
623 {
624         u16 *clear, *d, *s;
625
626         if (t + nr >= b)
627                 nr = b - t - 1;
628         if (b > vc->vc_rows || t >= b || nr < 1)
629                 return;
630         vc_uniscr_scroll(vc, t, b, dir, nr);
631         if (con_is_visible(vc) && vc->vc_sw->con_scroll(vc, t, b, dir, nr))
632                 return;
633
634         s = clear = (u16 *)(vc->vc_origin + vc->vc_size_row * t);
635         d = (u16 *)(vc->vc_origin + vc->vc_size_row * (t + nr));
636
637         if (dir == SM_UP) {
638                 clear = s + (b - t - nr) * vc->vc_cols;
639                 swap(s, d);
640         }
641         scr_memmovew(d, s, (b - t - nr) * vc->vc_size_row);
642         scr_memsetw(clear, vc->vc_video_erase_char, vc->vc_size_row * nr);
643 }
644
645 static void do_update_region(struct vc_data *vc, unsigned long start, int count)
646 {
647         unsigned int xx, yy, offset;
648         u16 *p;
649
650         p = (u16 *) start;
651         if (!vc->vc_sw->con_getxy) {
652                 offset = (start - vc->vc_origin) / 2;
653                 xx = offset % vc->vc_cols;
654                 yy = offset / vc->vc_cols;
655         } else {
656                 int nxx, nyy;
657                 start = vc->vc_sw->con_getxy(vc, start, &nxx, &nyy);
658                 xx = nxx; yy = nyy;
659         }
660         for(;;) {
661                 u16 attrib = scr_readw(p) & 0xff00;
662                 int startx = xx;
663                 u16 *q = p;
664                 while (xx < vc->vc_cols && count) {
665                         if (attrib != (scr_readw(p) & 0xff00)) {
666                                 if (p > q)
667                                         vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
668                                 startx = xx;
669                                 q = p;
670                                 attrib = scr_readw(p) & 0xff00;
671                         }
672                         p++;
673                         xx++;
674                         count--;
675                 }
676                 if (p > q)
677                         vc->vc_sw->con_putcs(vc, q, p-q, yy, startx);
678                 if (!count)
679                         break;
680                 xx = 0;
681                 yy++;
682                 if (vc->vc_sw->con_getxy) {
683                         p = (u16 *)start;
684                         start = vc->vc_sw->con_getxy(vc, start, NULL, NULL);
685                 }
686         }
687 }
688
689 void update_region(struct vc_data *vc, unsigned long start, int count)
690 {
691         WARN_CONSOLE_UNLOCKED();
692
693         if (con_should_update(vc)) {
694                 hide_cursor(vc);
695                 do_update_region(vc, start, count);
696                 set_cursor(vc);
697         }
698 }
699
700 /* Structure of attributes is hardware-dependent */
701
702 static u8 build_attr(struct vc_data *vc, u8 _color, u8 _intensity, u8 _blink,
703     u8 _underline, u8 _reverse, u8 _italic)
704 {
705         if (vc->vc_sw->con_build_attr)
706                 return vc->vc_sw->con_build_attr(vc, _color, _intensity,
707                        _blink, _underline, _reverse, _italic);
708
709 /*
710  * ++roman: I completely changed the attribute format for monochrome
711  * mode (!can_do_color). The formerly used MDA (monochrome display
712  * adapter) format didn't allow the combination of certain effects.
713  * Now the attribute is just a bit vector:
714  *  Bit 0..1: intensity (0..2)
715  *  Bit 2   : underline
716  *  Bit 3   : reverse
717  *  Bit 7   : blink
718  */
719         {
720         u8 a = _color;
721         if (!vc->vc_can_do_color)
722                 return _intensity |
723                        (_italic ? 2 : 0) |
724                        (_underline ? 4 : 0) |
725                        (_reverse ? 8 : 0) |
726                        (_blink ? 0x80 : 0);
727         if (_italic)
728                 a = (a & 0xF0) | vc->vc_itcolor;
729         else if (_underline)
730                 a = (a & 0xf0) | vc->vc_ulcolor;
731         else if (_intensity == 0)
732                 a = (a & 0xf0) | vc->vc_halfcolor;
733         if (_reverse)
734                 a = ((a) & 0x88) | ((((a) >> 4) | ((a) << 4)) & 0x77);
735         if (_blink)
736                 a ^= 0x80;
737         if (_intensity == 2)
738                 a ^= 0x08;
739         if (vc->vc_hi_font_mask == 0x100)
740                 a <<= 1;
741         return a;
742         }
743 }
744
745 static void update_attr(struct vc_data *vc)
746 {
747         vc->vc_attr = build_attr(vc, vc->vc_color, vc->vc_intensity,
748                       vc->vc_blink, vc->vc_underline,
749                       vc->vc_reverse ^ vc->vc_decscnm, vc->vc_italic);
750         vc->vc_video_erase_char = (build_attr(vc, vc->vc_color, 1, vc->vc_blink, 0, vc->vc_decscnm, 0) << 8) | ' ';
751 }
752
753 /* Note: inverting the screen twice should revert to the original state */
754 void invert_screen(struct vc_data *vc, int offset, int count, int viewed)
755 {
756         unsigned short *p;
757
758         WARN_CONSOLE_UNLOCKED();
759
760         count /= 2;
761         p = screenpos(vc, offset, viewed);
762         if (vc->vc_sw->con_invert_region) {
763                 vc->vc_sw->con_invert_region(vc, p, count);
764         } else {
765                 u16 *q = p;
766                 int cnt = count;
767                 u16 a;
768
769                 if (!vc->vc_can_do_color) {
770                         while (cnt--) {
771                             a = scr_readw(q);
772                             a ^= 0x0800;
773                             scr_writew(a, q);
774                             q++;
775                         }
776                 } else if (vc->vc_hi_font_mask == 0x100) {
777                         while (cnt--) {
778                                 a = scr_readw(q);
779                                 a = ((a) & 0x11ff) | (((a) & 0xe000) >> 4) | (((a) & 0x0e00) << 4);
780                                 scr_writew(a, q);
781                                 q++;
782                         }
783                 } else {
784                         while (cnt--) {
785                                 a = scr_readw(q);
786                                 a = ((a) & 0x88ff) | (((a) & 0x7000) >> 4) | (((a) & 0x0700) << 4);
787                                 scr_writew(a, q);
788                                 q++;
789                         }
790                 }
791         }
792
793         if (con_should_update(vc))
794                 do_update_region(vc, (unsigned long) p, count);
795         notify_update(vc);
796 }
797
798 /* used by selection: complement pointer position */
799 void complement_pos(struct vc_data *vc, int offset)
800 {
801         static int old_offset = -1;
802         static unsigned short old;
803         static unsigned short oldx, oldy;
804
805         WARN_CONSOLE_UNLOCKED();
806
807         if (old_offset != -1 && old_offset >= 0 &&
808             old_offset < vc->vc_screenbuf_size) {
809                 scr_writew(old, screenpos(vc, old_offset, 1));
810                 if (con_should_update(vc))
811                         vc->vc_sw->con_putc(vc, old, oldy, oldx);
812                 notify_update(vc);
813         }
814
815         old_offset = offset;
816
817         if (offset != -1 && offset >= 0 &&
818             offset < vc->vc_screenbuf_size) {
819                 unsigned short new;
820                 unsigned short *p;
821                 p = screenpos(vc, offset, 1);
822                 old = scr_readw(p);
823                 new = old ^ vc->vc_complement_mask;
824                 scr_writew(new, p);
825                 if (con_should_update(vc)) {
826                         oldx = (offset >> 1) % vc->vc_cols;
827                         oldy = (offset >> 1) / vc->vc_cols;
828                         vc->vc_sw->con_putc(vc, new, oldy, oldx);
829                 }
830                 notify_update(vc);
831         }
832 }
833
834 static void insert_char(struct vc_data *vc, unsigned int nr)
835 {
836         unsigned short *p = (unsigned short *) vc->vc_pos;
837
838         vc_uniscr_insert(vc, nr);
839         scr_memmovew(p + nr, p, (vc->vc_cols - vc->vc_x - nr) * 2);
840         scr_memsetw(p, vc->vc_video_erase_char, nr * 2);
841         vc->vc_need_wrap = 0;
842         if (con_should_update(vc))
843                 do_update_region(vc, (unsigned long) p,
844                         vc->vc_cols - vc->vc_x);
845 }
846
847 static void delete_char(struct vc_data *vc, unsigned int nr)
848 {
849         unsigned short *p = (unsigned short *) vc->vc_pos;
850
851         vc_uniscr_delete(vc, nr);
852         scr_memcpyw(p, p + nr, (vc->vc_cols - vc->vc_x - nr) * 2);
853         scr_memsetw(p + vc->vc_cols - vc->vc_x - nr, vc->vc_video_erase_char,
854                         nr * 2);
855         vc->vc_need_wrap = 0;
856         if (con_should_update(vc))
857                 do_update_region(vc, (unsigned long) p,
858                         vc->vc_cols - vc->vc_x);
859 }
860
861 static int softcursor_original = -1;
862
863 static void add_softcursor(struct vc_data *vc)
864 {
865         int i = scr_readw((u16 *) vc->vc_pos);
866         u32 type = vc->vc_cursor_type;
867
868         if (! (type & 0x10)) return;
869         if (softcursor_original != -1) return;
870         softcursor_original = i;
871         i |= ((type >> 8) & 0xff00 );
872         i ^= ((type) & 0xff00 );
873         if ((type & 0x20) && ((softcursor_original & 0x7000) == (i & 0x7000))) i ^= 0x7000;
874         if ((type & 0x40) && ((i & 0x700) == ((i & 0x7000) >> 4))) i ^= 0x0700;
875         scr_writew(i, (u16 *) vc->vc_pos);
876         if (con_should_update(vc))
877                 vc->vc_sw->con_putc(vc, i, vc->vc_y, vc->vc_x);
878 }
879
880 static void hide_softcursor(struct vc_data *vc)
881 {
882         if (softcursor_original != -1) {
883                 scr_writew(softcursor_original, (u16 *)vc->vc_pos);
884                 if (con_should_update(vc))
885                         vc->vc_sw->con_putc(vc, softcursor_original,
886                                         vc->vc_y, vc->vc_x);
887                 softcursor_original = -1;
888         }
889 }
890
891 static void hide_cursor(struct vc_data *vc)
892 {
893         if (vc == sel_cons)
894                 clear_selection();
895         vc->vc_sw->con_cursor(vc, CM_ERASE);
896         hide_softcursor(vc);
897 }
898
899 static void set_cursor(struct vc_data *vc)
900 {
901         if (!con_is_fg(vc) || console_blanked || vc->vc_mode == KD_GRAPHICS)
902                 return;
903         if (vc->vc_deccm) {
904                 if (vc == sel_cons)
905                         clear_selection();
906                 add_softcursor(vc);
907                 if ((vc->vc_cursor_type & 0x0f) != 1)
908                         vc->vc_sw->con_cursor(vc, CM_DRAW);
909         } else
910                 hide_cursor(vc);
911 }
912
913 static void set_origin(struct vc_data *vc)
914 {
915         WARN_CONSOLE_UNLOCKED();
916
917         if (!con_is_visible(vc) ||
918             !vc->vc_sw->con_set_origin ||
919             !vc->vc_sw->con_set_origin(vc))
920                 vc->vc_origin = (unsigned long)vc->vc_screenbuf;
921         vc->vc_visible_origin = vc->vc_origin;
922         vc->vc_scr_end = vc->vc_origin + vc->vc_screenbuf_size;
923         vc->vc_pos = vc->vc_origin + vc->vc_size_row * vc->vc_y + 2 * vc->vc_x;
924 }
925
926 static void save_screen(struct vc_data *vc)
927 {
928         WARN_CONSOLE_UNLOCKED();
929
930         if (vc->vc_sw->con_save_screen)
931                 vc->vc_sw->con_save_screen(vc);
932 }
933
934 static void flush_scrollback(struct vc_data *vc)
935 {
936         WARN_CONSOLE_UNLOCKED();
937
938         if (vc->vc_sw->con_flush_scrollback)
939                 vc->vc_sw->con_flush_scrollback(vc);
940 }
941
942 /*
943  *      Redrawing of screen
944  */
945
946 void clear_buffer_attributes(struct vc_data *vc)
947 {
948         unsigned short *p = (unsigned short *)vc->vc_origin;
949         int count = vc->vc_screenbuf_size / 2;
950         int mask = vc->vc_hi_font_mask | 0xff;
951
952         for (; count > 0; count--, p++) {
953                 scr_writew((scr_readw(p)&mask) | (vc->vc_video_erase_char & ~mask), p);
954         }
955 }
956
957 void redraw_screen(struct vc_data *vc, int is_switch)
958 {
959         int redraw = 0;
960
961         WARN_CONSOLE_UNLOCKED();
962
963         if (!vc) {
964                 /* strange ... */
965                 /* printk("redraw_screen: tty %d not allocated ??\n", new_console+1); */
966                 return;
967         }
968
969         if (is_switch) {
970                 struct vc_data *old_vc = vc_cons[fg_console].d;
971                 if (old_vc == vc)
972                         return;
973                 if (!con_is_visible(vc))
974                         redraw = 1;
975                 *vc->vc_display_fg = vc;
976                 fg_console = vc->vc_num;
977                 hide_cursor(old_vc);
978                 if (!con_is_visible(old_vc)) {
979                         save_screen(old_vc);
980                         set_origin(old_vc);
981                 }
982                 if (tty0dev)
983                         sysfs_notify(&tty0dev->kobj, NULL, "active");
984         } else {
985                 hide_cursor(vc);
986                 redraw = 1;
987         }
988
989         if (redraw) {
990                 int update;
991                 int old_was_color = vc->vc_can_do_color;
992
993                 set_origin(vc);
994                 update = vc->vc_sw->con_switch(vc);
995                 set_palette(vc);
996                 /*
997                  * If console changed from mono<->color, the best we can do
998                  * is to clear the buffer attributes. As it currently stands,
999                  * rebuilding new attributes from the old buffer is not doable
1000                  * without overly complex code.
1001                  */
1002                 if (old_was_color != vc->vc_can_do_color) {
1003                         update_attr(vc);
1004                         clear_buffer_attributes(vc);
1005                 }
1006
1007                 /* Forcibly update if we're panicing */
1008                 if ((update && vc->vc_mode != KD_GRAPHICS) ||
1009                     vt_force_oops_output(vc))
1010                         do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
1011         }
1012         set_cursor(vc);
1013         if (is_switch) {
1014                 set_leds();
1015                 compute_shiftstate();
1016                 notify_update(vc);
1017         }
1018 }
1019
1020 /*
1021  *      Allocation, freeing and resizing of VTs.
1022  */
1023
1024 int vc_cons_allocated(unsigned int i)
1025 {
1026         return (i < MAX_NR_CONSOLES && vc_cons[i].d);
1027 }
1028
1029 static void visual_init(struct vc_data *vc, int num, int init)
1030 {
1031         /* ++Geert: vc->vc_sw->con_init determines console size */
1032         if (vc->vc_sw)
1033                 module_put(vc->vc_sw->owner);
1034         vc->vc_sw = conswitchp;
1035 #ifndef VT_SINGLE_DRIVER
1036         if (con_driver_map[num])
1037                 vc->vc_sw = con_driver_map[num];
1038 #endif
1039         __module_get(vc->vc_sw->owner);
1040         vc->vc_num = num;
1041         vc->vc_display_fg = &master_display_fg;
1042         if (vc->vc_uni_pagedir_loc)
1043                 con_free_unimap(vc);
1044         vc->vc_uni_pagedir_loc = &vc->vc_uni_pagedir;
1045         vc->vc_uni_pagedir = NULL;
1046         vc->vc_hi_font_mask = 0;
1047         vc->vc_complement_mask = 0;
1048         vc->vc_can_do_color = 0;
1049         vc->vc_panic_force_write = false;
1050         vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1051         vc->vc_sw->con_init(vc, init);
1052         if (!vc->vc_complement_mask)
1053                 vc->vc_complement_mask = vc->vc_can_do_color ? 0x7700 : 0x0800;
1054         vc->vc_s_complement_mask = vc->vc_complement_mask;
1055         vc->vc_size_row = vc->vc_cols << 1;
1056         vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
1057 }
1058
1059 int vc_allocate(unsigned int currcons)  /* return 0 on success */
1060 {
1061         struct vt_notifier_param param;
1062         struct vc_data *vc;
1063
1064         WARN_CONSOLE_UNLOCKED();
1065
1066         if (currcons >= MAX_NR_CONSOLES)
1067                 return -ENXIO;
1068
1069         if (vc_cons[currcons].d)
1070                 return 0;
1071
1072         /* due to the granularity of kmalloc, we waste some memory here */
1073         /* the alloc is done in two steps, to optimize the common situation
1074            of a 25x80 console (structsize=216, screenbuf_size=4000) */
1075         /* although the numbers above are not valid since long ago, the
1076            point is still up-to-date and the comment still has its value
1077            even if only as a historical artifact.  --mj, July 1998 */
1078         param.vc = vc = kzalloc(sizeof(struct vc_data), GFP_KERNEL);
1079         if (!vc)
1080                 return -ENOMEM;
1081
1082         vc_cons[currcons].d = vc;
1083         tty_port_init(&vc->port);
1084         INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK);
1085
1086         visual_init(vc, currcons, 1);
1087
1088         if (!*vc->vc_uni_pagedir_loc)
1089                 con_set_default_unimap(vc);
1090
1091         vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL);
1092         if (!vc->vc_screenbuf)
1093                 goto err_free;
1094
1095         /* If no drivers have overridden us and the user didn't pass a
1096            boot option, default to displaying the cursor */
1097         if (global_cursor_default == -1)
1098                 global_cursor_default = 1;
1099
1100         vc_init(vc, vc->vc_rows, vc->vc_cols, 1);
1101         vcs_make_sysfs(currcons);
1102         atomic_notifier_call_chain(&vt_notifier_list, VT_ALLOCATE, &param);
1103
1104         return 0;
1105 err_free:
1106         kfree(vc);
1107         vc_cons[currcons].d = NULL;
1108         return -ENOMEM;
1109 }
1110
1111 static inline int resize_screen(struct vc_data *vc, int width, int height,
1112                                 int user)
1113 {
1114         /* Resizes the resolution of the display adapater */
1115         int err = 0;
1116
1117         if (vc->vc_mode != KD_GRAPHICS && vc->vc_sw->con_resize)
1118                 err = vc->vc_sw->con_resize(vc, width, height, user);
1119
1120         return err;
1121 }
1122
1123 /*
1124  * Change # of rows and columns (0 means unchanged/the size of fg_console)
1125  * [this is to be used together with some user program
1126  * like resize that changes the hardware videomode]
1127  */
1128 #define VC_RESIZE_MAXCOL (32767)
1129 #define VC_RESIZE_MAXROW (32767)
1130
1131 /**
1132  *      vc_do_resize    -       resizing method for the tty
1133  *      @tty: tty being resized
1134  *      @real_tty: real tty (different to tty if a pty/tty pair)
1135  *      @vc: virtual console private data
1136  *      @cols: columns
1137  *      @lines: lines
1138  *
1139  *      Resize a virtual console, clipping according to the actual constraints.
1140  *      If the caller passes a tty structure then update the termios winsize
1141  *      information and perform any necessary signal handling.
1142  *
1143  *      Caller must hold the console semaphore. Takes the termios rwsem and
1144  *      ctrl_lock of the tty IFF a tty is passed.
1145  */
1146
1147 static int vc_do_resize(struct tty_struct *tty, struct vc_data *vc,
1148                                 unsigned int cols, unsigned int lines)
1149 {
1150         unsigned long old_origin, new_origin, new_scr_end, rlth, rrem, err = 0;
1151         unsigned long end;
1152         unsigned int old_rows, old_row_size, first_copied_row;
1153         unsigned int new_cols, new_rows, new_row_size, new_screen_size;
1154         unsigned int user;
1155         unsigned short *newscreen;
1156         struct uni_screen *new_uniscr = NULL;
1157
1158         WARN_CONSOLE_UNLOCKED();
1159
1160         if (!vc)
1161                 return -ENXIO;
1162
1163         user = vc->vc_resize_user;
1164         vc->vc_resize_user = 0;
1165
1166         if (cols > VC_RESIZE_MAXCOL || lines > VC_RESIZE_MAXROW)
1167                 return -EINVAL;
1168
1169         new_cols = (cols ? cols : vc->vc_cols);
1170         new_rows = (lines ? lines : vc->vc_rows);
1171         new_row_size = new_cols << 1;
1172         new_screen_size = new_row_size * new_rows;
1173
1174         if (new_cols == vc->vc_cols && new_rows == vc->vc_rows)
1175                 return 0;
1176
1177         if (new_screen_size > (4 << 20))
1178                 return -EINVAL;
1179         newscreen = kzalloc(new_screen_size, GFP_USER);
1180         if (!newscreen)
1181                 return -ENOMEM;
1182
1183         if (get_vc_uniscr(vc)) {
1184                 new_uniscr = vc_uniscr_alloc(new_cols, new_rows);
1185                 if (!new_uniscr) {
1186                         kfree(newscreen);
1187                         return -ENOMEM;
1188                 }
1189         }
1190
1191         if (vc == sel_cons)
1192                 clear_selection();
1193
1194         old_rows = vc->vc_rows;
1195         old_row_size = vc->vc_size_row;
1196
1197         err = resize_screen(vc, new_cols, new_rows, user);
1198         if (err) {
1199                 kfree(newscreen);
1200                 kfree(new_uniscr);
1201                 return err;
1202         }
1203
1204         vc->vc_rows = new_rows;
1205         vc->vc_cols = new_cols;
1206         vc->vc_size_row = new_row_size;
1207         vc->vc_screenbuf_size = new_screen_size;
1208
1209         rlth = min(old_row_size, new_row_size);
1210         rrem = new_row_size - rlth;
1211         old_origin = vc->vc_origin;
1212         new_origin = (long) newscreen;
1213         new_scr_end = new_origin + new_screen_size;
1214
1215         if (vc->vc_y > new_rows) {
1216                 if (old_rows - vc->vc_y < new_rows) {
1217                         /*
1218                          * Cursor near the bottom, copy contents from the
1219                          * bottom of buffer
1220                          */
1221                         first_copied_row = (old_rows - new_rows);
1222                 } else {
1223                         /*
1224                          * Cursor is in no man's land, copy 1/2 screenful
1225                          * from the top and bottom of cursor position
1226                          */
1227                         first_copied_row = (vc->vc_y - new_rows/2);
1228                 }
1229                 old_origin += first_copied_row * old_row_size;
1230         } else
1231                 first_copied_row = 0;
1232         end = old_origin + old_row_size * min(old_rows, new_rows);
1233
1234         vc_uniscr_copy_area(new_uniscr, new_cols, new_rows,
1235                             get_vc_uniscr(vc), rlth/2, first_copied_row,
1236                             min(old_rows, new_rows));
1237         vc_uniscr_set(vc, new_uniscr);
1238
1239         update_attr(vc);
1240
1241         while (old_origin < end) {
1242                 scr_memcpyw((unsigned short *) new_origin,
1243                             (unsigned short *) old_origin, rlth);
1244                 if (rrem)
1245                         scr_memsetw((void *)(new_origin + rlth),
1246                                     vc->vc_video_erase_char, rrem);
1247                 old_origin += old_row_size;
1248                 new_origin += new_row_size;
1249         }
1250         if (new_scr_end > new_origin)
1251                 scr_memsetw((void *)new_origin, vc->vc_video_erase_char,
1252                             new_scr_end - new_origin);
1253         kfree(vc->vc_screenbuf);
1254         vc->vc_screenbuf = newscreen;
1255         vc->vc_screenbuf_size = new_screen_size;
1256         set_origin(vc);
1257
1258         /* do part of a reset_terminal() */
1259         vc->vc_top = 0;
1260         vc->vc_bottom = vc->vc_rows;
1261         gotoxy(vc, vc->vc_x, vc->vc_y);
1262         save_cur(vc);
1263
1264         if (tty) {
1265                 /* Rewrite the requested winsize data with the actual
1266                    resulting sizes */
1267                 struct winsize ws;
1268                 memset(&ws, 0, sizeof(ws));
1269                 ws.ws_row = vc->vc_rows;
1270                 ws.ws_col = vc->vc_cols;
1271                 ws.ws_ypixel = vc->vc_scan_lines;
1272                 tty_do_resize(tty, &ws);
1273         }
1274
1275         if (con_is_visible(vc))
1276                 update_screen(vc);
1277         vt_event_post(VT_EVENT_RESIZE, vc->vc_num, vc->vc_num);
1278         return err;
1279 }
1280
1281 /**
1282  *      vc_resize               -       resize a VT
1283  *      @vc: virtual console
1284  *      @cols: columns
1285  *      @rows: rows
1286  *
1287  *      Resize a virtual console as seen from the console end of things. We
1288  *      use the common vc_do_resize methods to update the structures. The
1289  *      caller must hold the console sem to protect console internals and
1290  *      vc->port.tty
1291  */
1292
1293 int vc_resize(struct vc_data *vc, unsigned int cols, unsigned int rows)
1294 {
1295         return vc_do_resize(vc->port.tty, vc, cols, rows);
1296 }
1297
1298 /**
1299  *      vt_resize               -       resize a VT
1300  *      @tty: tty to resize
1301  *      @ws: winsize attributes
1302  *
1303  *      Resize a virtual terminal. This is called by the tty layer as we
1304  *      register our own handler for resizing. The mutual helper does all
1305  *      the actual work.
1306  *
1307  *      Takes the console sem and the called methods then take the tty
1308  *      termios_rwsem and the tty ctrl_lock in that order.
1309  */
1310 static int vt_resize(struct tty_struct *tty, struct winsize *ws)
1311 {
1312         struct vc_data *vc = tty->driver_data;
1313         int ret;
1314
1315         console_lock();
1316         ret = vc_do_resize(tty, vc, ws->ws_col, ws->ws_row);
1317         console_unlock();
1318         return ret;
1319 }
1320
1321 struct vc_data *vc_deallocate(unsigned int currcons)
1322 {
1323         struct vc_data *vc = NULL;
1324
1325         WARN_CONSOLE_UNLOCKED();
1326
1327         if (vc_cons_allocated(currcons)) {
1328                 struct vt_notifier_param param;
1329
1330                 param.vc = vc = vc_cons[currcons].d;
1331                 atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, &param);
1332                 vcs_remove_sysfs(currcons);
1333                 vc->vc_sw->con_deinit(vc);
1334                 put_pid(vc->vt_pid);
1335                 module_put(vc->vc_sw->owner);
1336                 vc_uniscr_set(vc, NULL);
1337                 kfree(vc->vc_screenbuf);
1338                 vc_cons[currcons].d = NULL;
1339         }
1340         return vc;
1341 }
1342
1343 /*
1344  *      VT102 emulator
1345  */
1346
1347 #define set_kbd(vc, x)  vt_set_kbd_mode_bit((vc)->vc_num, (x))
1348 #define clr_kbd(vc, x)  vt_clr_kbd_mode_bit((vc)->vc_num, (x))
1349 #define is_kbd(vc, x)   vt_get_kbd_mode_bit((vc)->vc_num, (x))
1350
1351 #define decarm          VC_REPEAT
1352 #define decckm          VC_CKMODE
1353 #define kbdapplic       VC_APPLIC
1354 #define lnm             VC_CRLF
1355
1356 /*
1357  * this is what the terminal answers to a ESC-Z or csi0c query.
1358  */
1359 #define VT100ID "\033[?1;2c"
1360 #define VT102ID "\033[?6c"
1361
1362 const unsigned char color_table[] = { 0, 4, 2, 6, 1, 5, 3, 7,
1363                                        8,12,10,14, 9,13,11,15 };
1364
1365 /* the default colour table, for VGA+ colour systems */
1366 unsigned char default_red[] = {
1367         0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa, 0x00, 0xaa,
1368         0x55, 0xff, 0x55, 0xff, 0x55, 0xff, 0x55, 0xff
1369 };
1370 module_param_array(default_red, byte, NULL, S_IRUGO | S_IWUSR);
1371
1372 unsigned char default_grn[] = {
1373         0x00, 0x00, 0xaa, 0x55, 0x00, 0x00, 0xaa, 0xaa,
1374         0x55, 0x55, 0xff, 0xff, 0x55, 0x55, 0xff, 0xff
1375 };
1376 module_param_array(default_grn, byte, NULL, S_IRUGO | S_IWUSR);
1377
1378 unsigned char default_blu[] = {
1379         0x00, 0x00, 0x00, 0x00, 0xaa, 0xaa, 0xaa, 0xaa,
1380         0x55, 0x55, 0x55, 0x55, 0xff, 0xff, 0xff, 0xff
1381 };
1382 module_param_array(default_blu, byte, NULL, S_IRUGO | S_IWUSR);
1383
1384 /*
1385  * gotoxy() must verify all boundaries, because the arguments
1386  * might also be negative. If the given position is out of
1387  * bounds, the cursor is placed at the nearest margin.
1388  */
1389 static void gotoxy(struct vc_data *vc, int new_x, int new_y)
1390 {
1391         int min_y, max_y;
1392
1393         if (new_x < 0)
1394                 vc->vc_x = 0;
1395         else {
1396                 if (new_x >= vc->vc_cols)
1397                         vc->vc_x = vc->vc_cols - 1;
1398                 else
1399                         vc->vc_x = new_x;
1400         }
1401
1402         if (vc->vc_decom) {
1403                 min_y = vc->vc_top;
1404                 max_y = vc->vc_bottom;
1405         } else {
1406                 min_y = 0;
1407                 max_y = vc->vc_rows;
1408         }
1409         if (new_y < min_y)
1410                 vc->vc_y = min_y;
1411         else if (new_y >= max_y)
1412                 vc->vc_y = max_y - 1;
1413         else
1414                 vc->vc_y = new_y;
1415         vc->vc_pos = vc->vc_origin + vc->vc_y * vc->vc_size_row + (vc->vc_x<<1);
1416         vc->vc_need_wrap = 0;
1417 }
1418
1419 /* for absolute user moves, when decom is set */
1420 static void gotoxay(struct vc_data *vc, int new_x, int new_y)
1421 {
1422         gotoxy(vc, new_x, vc->vc_decom ? (vc->vc_top + new_y) : new_y);
1423 }
1424
1425 void scrollback(struct vc_data *vc)
1426 {
1427         scrolldelta(-(vc->vc_rows / 2));
1428 }
1429
1430 void scrollfront(struct vc_data *vc, int lines)
1431 {
1432         if (!lines)
1433                 lines = vc->vc_rows / 2;
1434         scrolldelta(lines);
1435 }
1436
1437 static void lf(struct vc_data *vc)
1438 {
1439         /* don't scroll if above bottom of scrolling region, or
1440          * if below scrolling region
1441          */
1442         if (vc->vc_y + 1 == vc->vc_bottom)
1443                 con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_UP, 1);
1444         else if (vc->vc_y < vc->vc_rows - 1) {
1445                 vc->vc_y++;
1446                 vc->vc_pos += vc->vc_size_row;
1447         }
1448         vc->vc_need_wrap = 0;
1449         notify_write(vc, '\n');
1450 }
1451
1452 static void ri(struct vc_data *vc)
1453 {
1454         /* don't scroll if below top of scrolling region, or
1455          * if above scrolling region
1456          */
1457         if (vc->vc_y == vc->vc_top)
1458                 con_scroll(vc, vc->vc_top, vc->vc_bottom, SM_DOWN, 1);
1459         else if (vc->vc_y > 0) {
1460                 vc->vc_y--;
1461                 vc->vc_pos -= vc->vc_size_row;
1462         }
1463         vc->vc_need_wrap = 0;
1464 }
1465
1466 static inline void cr(struct vc_data *vc)
1467 {
1468         vc->vc_pos -= vc->vc_x << 1;
1469         vc->vc_need_wrap = vc->vc_x = 0;
1470         notify_write(vc, '\r');
1471 }
1472
1473 static inline void bs(struct vc_data *vc)
1474 {
1475         if (vc->vc_x) {
1476                 vc->vc_pos -= 2;
1477                 vc->vc_x--;
1478                 vc->vc_need_wrap = 0;
1479                 notify_write(vc, '\b');
1480         }
1481 }
1482
1483 static inline void del(struct vc_data *vc)
1484 {
1485         /* ignored */
1486 }
1487
1488 static void csi_J(struct vc_data *vc, int vpar)
1489 {
1490         unsigned int count;
1491         unsigned short * start;
1492
1493         switch (vpar) {
1494                 case 0: /* erase from cursor to end of display */
1495                         vc_uniscr_clear_line(vc, vc->vc_x,
1496                                              vc->vc_cols - vc->vc_x);
1497                         vc_uniscr_clear_lines(vc, vc->vc_y + 1,
1498                                               vc->vc_rows - vc->vc_y - 1);
1499                         count = (vc->vc_scr_end - vc->vc_pos) >> 1;
1500                         start = (unsigned short *)vc->vc_pos;
1501                         break;
1502                 case 1: /* erase from start to cursor */
1503                         vc_uniscr_clear_line(vc, 0, vc->vc_x + 1);
1504                         vc_uniscr_clear_lines(vc, 0, vc->vc_y);
1505                         count = ((vc->vc_pos - vc->vc_origin) >> 1) + 1;
1506                         start = (unsigned short *)vc->vc_origin;
1507                         break;
1508                 case 2: /* erase whole display */
1509                 case 3: /* (and scrollback buffer later) */
1510                         vc_uniscr_clear_lines(vc, 0, vc->vc_rows);
1511                         count = vc->vc_cols * vc->vc_rows;
1512                         start = (unsigned short *)vc->vc_origin;
1513                         break;
1514                 default:
1515                         return;
1516         }
1517         scr_memsetw(start, vc->vc_video_erase_char, 2 * count);
1518         if (vpar == 3) {
1519                 set_origin(vc);
1520                 flush_scrollback(vc);
1521                 if (con_is_visible(vc))
1522                         update_screen(vc);
1523         } else if (con_should_update(vc))
1524                 do_update_region(vc, (unsigned long) start, count);
1525         vc->vc_need_wrap = 0;
1526 }
1527
1528 static void csi_K(struct vc_data *vc, int vpar)
1529 {
1530         unsigned int count;
1531         unsigned short *start = (unsigned short *)vc->vc_pos;
1532         int offset;
1533
1534         switch (vpar) {
1535                 case 0: /* erase from cursor to end of line */
1536                         offset = 0;
1537                         count = vc->vc_cols - vc->vc_x;
1538                         break;
1539                 case 1: /* erase from start of line to cursor */
1540                         offset = -vc->vc_x;
1541                         count = vc->vc_x + 1;
1542                         break;
1543                 case 2: /* erase whole line */
1544                         offset = -vc->vc_x;
1545                         count = vc->vc_cols;
1546                         break;
1547                 default:
1548                         return;
1549         }
1550         vc_uniscr_clear_line(vc, vc->vc_x + offset, count);
1551         scr_memsetw(start + offset, vc->vc_video_erase_char, 2 * count);
1552         vc->vc_need_wrap = 0;
1553         if (con_should_update(vc))
1554                 do_update_region(vc, (unsigned long)(start + offset), count);
1555 }
1556
1557 static void csi_X(struct vc_data *vc, int vpar) /* erase the following vpar positions */
1558 {                                         /* not vt100? */
1559         int count;
1560
1561         if (!vpar)
1562                 vpar++;
1563         count = (vpar > vc->vc_cols - vc->vc_x) ? (vc->vc_cols - vc->vc_x) : vpar;
1564
1565         vc_uniscr_clear_line(vc, vc->vc_x, count);
1566         scr_memsetw((unsigned short *)vc->vc_pos, vc->vc_video_erase_char, 2 * count);
1567         if (con_should_update(vc))
1568                 vc->vc_sw->con_clear(vc, vc->vc_y, vc->vc_x, 1, count);
1569         vc->vc_need_wrap = 0;
1570 }
1571
1572 static void default_attr(struct vc_data *vc)
1573 {
1574         vc->vc_intensity = 1;
1575         vc->vc_italic = 0;
1576         vc->vc_underline = 0;
1577         vc->vc_reverse = 0;
1578         vc->vc_blink = 0;
1579         vc->vc_color = vc->vc_def_color;
1580 }
1581
1582 struct rgb { u8 r; u8 g; u8 b; };
1583
1584 static void rgb_from_256(int i, struct rgb *c)
1585 {
1586         if (i < 8) {            /* Standard colours. */
1587                 c->r = i&1 ? 0xaa : 0x00;
1588                 c->g = i&2 ? 0xaa : 0x00;
1589                 c->b = i&4 ? 0xaa : 0x00;
1590         } else if (i < 16) {
1591                 c->r = i&1 ? 0xff : 0x55;
1592                 c->g = i&2 ? 0xff : 0x55;
1593                 c->b = i&4 ? 0xff : 0x55;
1594         } else if (i < 232) {   /* 6x6x6 colour cube. */
1595                 c->r = (i - 16) / 36 * 85 / 2;
1596                 c->g = (i - 16) / 6 % 6 * 85 / 2;
1597                 c->b = (i - 16) % 6 * 85 / 2;
1598         } else                  /* Grayscale ramp. */
1599                 c->r = c->g = c->b = i * 10 - 2312;
1600 }
1601
1602 static void rgb_foreground(struct vc_data *vc, const struct rgb *c)
1603 {
1604         u8 hue = 0, max = max3(c->r, c->g, c->b);
1605
1606         if (c->r > max / 2)
1607                 hue |= 4;
1608         if (c->g > max / 2)
1609                 hue |= 2;
1610         if (c->b > max / 2)
1611                 hue |= 1;
1612
1613         if (hue == 7 && max <= 0x55) {
1614                 hue = 0;
1615                 vc->vc_intensity = 2;
1616         } else if (max > 0xaa)
1617                 vc->vc_intensity = 2;
1618         else
1619                 vc->vc_intensity = 1;
1620
1621         vc->vc_color = (vc->vc_color & 0xf0) | hue;
1622 }
1623
1624 static void rgb_background(struct vc_data *vc, const struct rgb *c)
1625 {
1626         /* For backgrounds, err on the dark side. */
1627         vc->vc_color = (vc->vc_color & 0x0f)
1628                 | (c->r&0x80) >> 1 | (c->g&0x80) >> 2 | (c->b&0x80) >> 3;
1629 }
1630
1631 /*
1632  * ITU T.416 Higher colour modes. They break the usual properties of SGR codes
1633  * and thus need to be detected and ignored by hand. Strictly speaking, that
1634  * standard also wants : rather than ; as separators, contrary to ECMA-48, but
1635  * no one produces such codes and almost no one accepts them.
1636  *
1637  * Subcommands 3 (CMY) and 4 (CMYK) are so insane there's no point in
1638  * supporting them.
1639  */
1640 static int vc_t416_color(struct vc_data *vc, int i,
1641                 void(*set_color)(struct vc_data *vc, const struct rgb *c))
1642 {
1643         struct rgb c;
1644
1645         i++;
1646         if (i > vc->vc_npar)
1647                 return i;
1648
1649         if (vc->vc_par[i] == 5 && i + 1 <= vc->vc_npar) {
1650                 /* 256 colours */
1651                 i++;
1652                 rgb_from_256(vc->vc_par[i], &c);
1653         } else if (vc->vc_par[i] == 2 && i + 3 <= vc->vc_npar) {
1654                 /* 24 bit */
1655                 c.r = vc->vc_par[i + 1];
1656                 c.g = vc->vc_par[i + 2];
1657                 c.b = vc->vc_par[i + 3];
1658                 i += 3;
1659         } else
1660                 return i;
1661
1662         set_color(vc, &c);
1663
1664         return i;
1665 }
1666
1667 /* console_lock is held */
1668 static void csi_m(struct vc_data *vc)
1669 {
1670         int i;
1671
1672         for (i = 0; i <= vc->vc_npar; i++)
1673                 switch (vc->vc_par[i]) {
1674                 case 0: /* all attributes off */
1675                         default_attr(vc);
1676                         break;
1677                 case 1:
1678                         vc->vc_intensity = 2;
1679                         break;
1680                 case 2:
1681                         vc->vc_intensity = 0;
1682                         break;
1683                 case 3:
1684                         vc->vc_italic = 1;
1685                         break;
1686                 case 21:
1687                         /*
1688                          * No console drivers support double underline, so
1689                          * convert it to a single underline.
1690                          */
1691                 case 4:
1692                         vc->vc_underline = 1;
1693                         break;
1694                 case 5:
1695                         vc->vc_blink = 1;
1696                         break;
1697                 case 7:
1698                         vc->vc_reverse = 1;
1699                         break;
1700                 case 10: /* ANSI X3.64-1979 (SCO-ish?)
1701                           * Select primary font, don't display control chars if
1702                           * defined, don't set bit 8 on output.
1703                           */
1704                         vc->vc_translate = set_translate(vc->vc_charset == 0
1705                                         ? vc->vc_G0_charset
1706                                         : vc->vc_G1_charset, vc);
1707                         vc->vc_disp_ctrl = 0;
1708                         vc->vc_toggle_meta = 0;
1709                         break;
1710                 case 11: /* ANSI X3.64-1979 (SCO-ish?)
1711                           * Select first alternate font, lets chars < 32 be
1712                           * displayed as ROM chars.
1713                           */
1714                         vc->vc_translate = set_translate(IBMPC_MAP, vc);
1715                         vc->vc_disp_ctrl = 1;
1716                         vc->vc_toggle_meta = 0;
1717                         break;
1718                 case 12: /* ANSI X3.64-1979 (SCO-ish?)
1719                           * Select second alternate font, toggle high bit
1720                           * before displaying as ROM char.
1721                           */
1722                         vc->vc_translate = set_translate(IBMPC_MAP, vc);
1723                         vc->vc_disp_ctrl = 1;
1724                         vc->vc_toggle_meta = 1;
1725                         break;
1726                 case 22:
1727                         vc->vc_intensity = 1;
1728                         break;
1729                 case 23:
1730                         vc->vc_italic = 0;
1731                         break;
1732                 case 24:
1733                         vc->vc_underline = 0;
1734                         break;
1735                 case 25:
1736                         vc->vc_blink = 0;
1737                         break;
1738                 case 27:
1739                         vc->vc_reverse = 0;
1740                         break;
1741                 case 38:
1742                         i = vc_t416_color(vc, i, rgb_foreground);
1743                         break;
1744                 case 48:
1745                         i = vc_t416_color(vc, i, rgb_background);
1746                         break;
1747                 case 39:
1748                         vc->vc_color = (vc->vc_def_color & 0x0f) |
1749                                 (vc->vc_color & 0xf0);
1750                         break;
1751                 case 49:
1752                         vc->vc_color = (vc->vc_def_color & 0xf0) |
1753                                 (vc->vc_color & 0x0f);
1754                         break;
1755                 default:
1756                         if (vc->vc_par[i] >= 90 && vc->vc_par[i] <= 107) {
1757                                 if (vc->vc_par[i] < 100)
1758                                         vc->vc_intensity = 2;
1759                                 vc->vc_par[i] -= 60;
1760                         }
1761                         if (vc->vc_par[i] >= 30 && vc->vc_par[i] <= 37)
1762                                 vc->vc_color = color_table[vc->vc_par[i] - 30]
1763                                         | (vc->vc_color & 0xf0);
1764                         else if (vc->vc_par[i] >= 40 && vc->vc_par[i] <= 47)
1765                                 vc->vc_color = (color_table[vc->vc_par[i] - 40] << 4)
1766                                         | (vc->vc_color & 0x0f);
1767                         break;
1768                 }
1769         update_attr(vc);
1770 }
1771
1772 static void respond_string(const char *p, struct tty_port *port)
1773 {
1774         while (*p) {
1775                 tty_insert_flip_char(port, *p, 0);
1776                 p++;
1777         }
1778         tty_schedule_flip(port);
1779 }
1780
1781 static void cursor_report(struct vc_data *vc, struct tty_struct *tty)
1782 {
1783         char buf[40];
1784
1785         sprintf(buf, "\033[%d;%dR", vc->vc_y + (vc->vc_decom ? vc->vc_top + 1 : 1), vc->vc_x + 1);
1786         respond_string(buf, tty->port);
1787 }
1788
1789 static inline void status_report(struct tty_struct *tty)
1790 {
1791         respond_string("\033[0n", tty->port);   /* Terminal ok */
1792 }
1793
1794 static inline void respond_ID(struct tty_struct *tty)
1795 {
1796         respond_string(VT102ID, tty->port);
1797 }
1798
1799 void mouse_report(struct tty_struct *tty, int butt, int mrx, int mry)
1800 {
1801         char buf[8];
1802
1803         sprintf(buf, "\033[M%c%c%c", (char)(' ' + butt), (char)('!' + mrx),
1804                 (char)('!' + mry));
1805         respond_string(buf, tty->port);
1806 }
1807
1808 /* invoked via ioctl(TIOCLINUX) and through set_selection */
1809 int mouse_reporting(void)
1810 {
1811         return vc_cons[fg_console].d->vc_report_mouse;
1812 }
1813
1814 /* console_lock is held */
1815 static void set_mode(struct vc_data *vc, int on_off)
1816 {
1817         int i;
1818
1819         for (i = 0; i <= vc->vc_npar; i++)
1820                 if (vc->vc_ques) {
1821                         switch(vc->vc_par[i]) { /* DEC private modes set/reset */
1822                         case 1:                 /* Cursor keys send ^[Ox/^[[x */
1823                                 if (on_off)
1824                                         set_kbd(vc, decckm);
1825                                 else
1826                                         clr_kbd(vc, decckm);
1827                                 break;
1828                         case 3: /* 80/132 mode switch unimplemented */
1829 #if 0
1830                                 vc_resize(deccolm ? 132 : 80, vc->vc_rows);
1831                                 /* this alone does not suffice; some user mode
1832                                    utility has to change the hardware regs */
1833 #endif
1834                                 break;
1835                         case 5:                 /* Inverted screen on/off */
1836                                 if (vc->vc_decscnm != on_off) {
1837                                         vc->vc_decscnm = on_off;
1838                                         invert_screen(vc, 0, vc->vc_screenbuf_size, 0);
1839                                         update_attr(vc);
1840                                 }
1841                                 break;
1842                         case 6:                 /* Origin relative/absolute */
1843                                 vc->vc_decom = on_off;
1844                                 gotoxay(vc, 0, 0);
1845                                 break;
1846                         case 7:                 /* Autowrap on/off */
1847                                 vc->vc_decawm = on_off;
1848                                 break;
1849                         case 8:                 /* Autorepeat on/off */
1850                                 if (on_off)
1851                                         set_kbd(vc, decarm);
1852                                 else
1853                                         clr_kbd(vc, decarm);
1854                                 break;
1855                         case 9:
1856                                 vc->vc_report_mouse = on_off ? 1 : 0;
1857                                 break;
1858                         case 25:                /* Cursor on/off */
1859                                 vc->vc_deccm = on_off;
1860                                 break;
1861                         case 1000:
1862                                 vc->vc_report_mouse = on_off ? 2 : 0;
1863                                 break;
1864                         }
1865                 } else {
1866                         switch(vc->vc_par[i]) { /* ANSI modes set/reset */
1867                         case 3:                 /* Monitor (display ctrls) */
1868                                 vc->vc_disp_ctrl = on_off;
1869                                 break;
1870                         case 4:                 /* Insert Mode on/off */
1871                                 vc->vc_decim = on_off;
1872                                 break;
1873                         case 20:                /* Lf, Enter == CrLf/Lf */
1874                                 if (on_off)
1875                                         set_kbd(vc, lnm);
1876                                 else
1877                                         clr_kbd(vc, lnm);
1878                                 break;
1879                         }
1880                 }
1881 }
1882
1883 /* console_lock is held */
1884 static void setterm_command(struct vc_data *vc)
1885 {
1886         switch(vc->vc_par[0]) {
1887                 case 1: /* set color for underline mode */
1888                         if (vc->vc_can_do_color &&
1889                                         vc->vc_par[1] < 16) {
1890                                 vc->vc_ulcolor = color_table[vc->vc_par[1]];
1891                                 if (vc->vc_underline)
1892                                         update_attr(vc);
1893                         }
1894                         break;
1895                 case 2: /* set color for half intensity mode */
1896                         if (vc->vc_can_do_color &&
1897                                         vc->vc_par[1] < 16) {
1898                                 vc->vc_halfcolor = color_table[vc->vc_par[1]];
1899                                 if (vc->vc_intensity == 0)
1900                                         update_attr(vc);
1901                         }
1902                         break;
1903                 case 8: /* store colors as defaults */
1904                         vc->vc_def_color = vc->vc_attr;
1905                         if (vc->vc_hi_font_mask == 0x100)
1906                                 vc->vc_def_color >>= 1;
1907                         default_attr(vc);
1908                         update_attr(vc);
1909                         break;
1910                 case 9: /* set blanking interval */
1911                         blankinterval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60;
1912                         poke_blanked_console();
1913                         break;
1914                 case 10: /* set bell frequency in Hz */
1915                         if (vc->vc_npar >= 1)
1916                                 vc->vc_bell_pitch = vc->vc_par[1];
1917                         else
1918                                 vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
1919                         break;
1920                 case 11: /* set bell duration in msec */
1921                         if (vc->vc_npar >= 1)
1922                                 vc->vc_bell_duration = (vc->vc_par[1] < 2000) ?
1923                                         msecs_to_jiffies(vc->vc_par[1]) : 0;
1924                         else
1925                                 vc->vc_bell_duration = DEFAULT_BELL_DURATION;
1926                         break;
1927                 case 12: /* bring specified console to the front */
1928                         if (vc->vc_par[1] >= 1 && vc_cons_allocated(vc->vc_par[1] - 1))
1929                                 set_console(vc->vc_par[1] - 1);
1930                         break;
1931                 case 13: /* unblank the screen */
1932                         poke_blanked_console();
1933                         break;
1934                 case 14: /* set vesa powerdown interval */
1935                         vesa_off_interval = ((vc->vc_par[1] < 60) ? vc->vc_par[1] : 60) * 60 * HZ;
1936                         break;
1937                 case 15: /* activate the previous console */
1938                         set_console(last_console);
1939                         break;
1940                 case 16: /* set cursor blink duration in msec */
1941                         if (vc->vc_npar >= 1 && vc->vc_par[1] >= 50 &&
1942                                         vc->vc_par[1] <= USHRT_MAX)
1943                                 vc->vc_cur_blink_ms = vc->vc_par[1];
1944                         else
1945                                 vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
1946                         break;
1947         }
1948 }
1949
1950 /* console_lock is held */
1951 static void csi_at(struct vc_data *vc, unsigned int nr)
1952 {
1953         if (nr > vc->vc_cols - vc->vc_x)
1954                 nr = vc->vc_cols - vc->vc_x;
1955         else if (!nr)
1956                 nr = 1;
1957         insert_char(vc, nr);
1958 }
1959
1960 /* console_lock is held */
1961 static void csi_L(struct vc_data *vc, unsigned int nr)
1962 {
1963         if (nr > vc->vc_rows - vc->vc_y)
1964                 nr = vc->vc_rows - vc->vc_y;
1965         else if (!nr)
1966                 nr = 1;
1967         con_scroll(vc, vc->vc_y, vc->vc_bottom, SM_DOWN, nr);
1968         vc->vc_need_wrap = 0;
1969 }
1970
1971 /* console_lock is held */
1972 static void csi_P(struct vc_data *vc, unsigned int nr)
1973 {
1974         if (nr > vc->vc_cols - vc->vc_x)
1975                 nr = vc->vc_cols - vc->vc_x;
1976         else if (!nr)
1977                 nr = 1;
1978         delete_char(vc, nr);
1979 }
1980
1981 /* console_lock is held */
1982 static void csi_M(struct vc_data *vc, unsigned int nr)
1983 {
1984         if (nr > vc->vc_rows - vc->vc_y)
1985                 nr = vc->vc_rows - vc->vc_y;
1986         else if (!nr)
1987                 nr=1;
1988         con_scroll(vc, vc->vc_y, vc->vc_bottom, SM_UP, nr);
1989         vc->vc_need_wrap = 0;
1990 }
1991
1992 /* console_lock is held (except via vc_init->reset_terminal */
1993 static void save_cur(struct vc_data *vc)
1994 {
1995         vc->vc_saved_x          = vc->vc_x;
1996         vc->vc_saved_y          = vc->vc_y;
1997         vc->vc_s_intensity      = vc->vc_intensity;
1998         vc->vc_s_italic         = vc->vc_italic;
1999         vc->vc_s_underline      = vc->vc_underline;
2000         vc->vc_s_blink          = vc->vc_blink;
2001         vc->vc_s_reverse        = vc->vc_reverse;
2002         vc->vc_s_charset        = vc->vc_charset;
2003         vc->vc_s_color          = vc->vc_color;
2004         vc->vc_saved_G0         = vc->vc_G0_charset;
2005         vc->vc_saved_G1         = vc->vc_G1_charset;
2006 }
2007
2008 /* console_lock is held */
2009 static void restore_cur(struct vc_data *vc)
2010 {
2011         gotoxy(vc, vc->vc_saved_x, vc->vc_saved_y);
2012         vc->vc_intensity        = vc->vc_s_intensity;
2013         vc->vc_italic           = vc->vc_s_italic;
2014         vc->vc_underline        = vc->vc_s_underline;
2015         vc->vc_blink            = vc->vc_s_blink;
2016         vc->vc_reverse          = vc->vc_s_reverse;
2017         vc->vc_charset          = vc->vc_s_charset;
2018         vc->vc_color            = vc->vc_s_color;
2019         vc->vc_G0_charset       = vc->vc_saved_G0;
2020         vc->vc_G1_charset       = vc->vc_saved_G1;
2021         vc->vc_translate        = set_translate(vc->vc_charset ? vc->vc_G1_charset : vc->vc_G0_charset, vc);
2022         update_attr(vc);
2023         vc->vc_need_wrap = 0;
2024 }
2025
2026 enum { ESnormal, ESesc, ESsquare, ESgetpars, ESfunckey,
2027         EShash, ESsetG0, ESsetG1, ESpercent, ESignore, ESnonstd,
2028         ESpalette, ESosc };
2029
2030 /* console_lock is held (except via vc_init()) */
2031 static void reset_terminal(struct vc_data *vc, int do_clear)
2032 {
2033         vc->vc_top              = 0;
2034         vc->vc_bottom           = vc->vc_rows;
2035         vc->vc_state            = ESnormal;
2036         vc->vc_ques             = 0;
2037         vc->vc_translate        = set_translate(LAT1_MAP, vc);
2038         vc->vc_G0_charset       = LAT1_MAP;
2039         vc->vc_G1_charset       = GRAF_MAP;
2040         vc->vc_charset          = 0;
2041         vc->vc_need_wrap        = 0;
2042         vc->vc_report_mouse     = 0;
2043         vc->vc_utf              = default_utf8;
2044         vc->vc_utf_count        = 0;
2045
2046         vc->vc_disp_ctrl        = 0;
2047         vc->vc_toggle_meta      = 0;
2048
2049         vc->vc_decscnm          = 0;
2050         vc->vc_decom            = 0;
2051         vc->vc_decawm           = 1;
2052         vc->vc_deccm            = global_cursor_default;
2053         vc->vc_decim            = 0;
2054
2055         vt_reset_keyboard(vc->vc_num);
2056
2057         vc->vc_cursor_type = cur_default;
2058         vc->vc_complement_mask = vc->vc_s_complement_mask;
2059
2060         default_attr(vc);
2061         update_attr(vc);
2062
2063         vc->vc_tab_stop[0]      =
2064         vc->vc_tab_stop[1]      =
2065         vc->vc_tab_stop[2]      =
2066         vc->vc_tab_stop[3]      =
2067         vc->vc_tab_stop[4]      =
2068         vc->vc_tab_stop[5]      =
2069         vc->vc_tab_stop[6]      =
2070         vc->vc_tab_stop[7]      = 0x01010101;
2071
2072         vc->vc_bell_pitch = DEFAULT_BELL_PITCH;
2073         vc->vc_bell_duration = DEFAULT_BELL_DURATION;
2074         vc->vc_cur_blink_ms = DEFAULT_CURSOR_BLINK_MS;
2075
2076         gotoxy(vc, 0, 0);
2077         save_cur(vc);
2078         if (do_clear)
2079             csi_J(vc, 2);
2080 }
2081
2082 /* console_lock is held */
2083 static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c)
2084 {
2085         /*
2086          *  Control characters can be used in the _middle_
2087          *  of an escape sequence.
2088          */
2089         if (vc->vc_state == ESosc && c>=8 && c<=13) /* ... except for OSC */
2090                 return;
2091         switch (c) {
2092         case 0:
2093                 return;
2094         case 7:
2095                 if (vc->vc_state == ESosc)
2096                         vc->vc_state = ESnormal;
2097                 else if (vc->vc_bell_duration)
2098                         kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration);
2099                 return;
2100         case 8:
2101                 bs(vc);
2102                 return;
2103         case 9:
2104                 vc->vc_pos -= (vc->vc_x << 1);
2105                 while (vc->vc_x < vc->vc_cols - 1) {
2106                         vc->vc_x++;
2107                         if (vc->vc_tab_stop[7 & (vc->vc_x >> 5)] & (1 << (vc->vc_x & 31)))
2108                                 break;
2109                 }
2110                 vc->vc_pos += (vc->vc_x << 1);
2111                 notify_write(vc, '\t');
2112                 return;
2113         case 10: case 11: case 12:
2114                 lf(vc);
2115                 if (!is_kbd(vc, lnm))
2116                         return;
2117         case 13:
2118                 cr(vc);
2119                 return;
2120         case 14:
2121                 vc->vc_charset = 1;
2122                 vc->vc_translate = set_translate(vc->vc_G1_charset, vc);
2123                 vc->vc_disp_ctrl = 1;
2124                 return;
2125         case 15:
2126                 vc->vc_charset = 0;
2127                 vc->vc_translate = set_translate(vc->vc_G0_charset, vc);
2128                 vc->vc_disp_ctrl = 0;
2129                 return;
2130         case 24: case 26:
2131                 vc->vc_state = ESnormal;
2132                 return;
2133         case 27:
2134                 vc->vc_state = ESesc;
2135                 return;
2136         case 127:
2137                 del(vc);
2138                 return;
2139         case 128+27:
2140                 vc->vc_state = ESsquare;
2141                 return;
2142         }
2143         switch(vc->vc_state) {
2144         case ESesc:
2145                 vc->vc_state = ESnormal;
2146                 switch (c) {
2147                 case '[':
2148                         vc->vc_state = ESsquare;
2149                         return;
2150                 case ']':
2151                         vc->vc_state = ESnonstd;
2152                         return;
2153                 case '%':
2154                         vc->vc_state = ESpercent;
2155                         return;
2156                 case 'E':
2157                         cr(vc);
2158                         lf(vc);
2159                         return;
2160                 case 'M':
2161                         ri(vc);
2162                         return;
2163                 case 'D':
2164                         lf(vc);
2165                         return;
2166                 case 'H':
2167                         vc->vc_tab_stop[7 & (vc->vc_x >> 5)] |= (1 << (vc->vc_x & 31));
2168                         return;
2169                 case 'Z':
2170                         respond_ID(tty);
2171                         return;
2172                 case '7':
2173                         save_cur(vc);
2174                         return;
2175                 case '8':
2176                         restore_cur(vc);
2177                         return;
2178                 case '(':
2179                         vc->vc_state = ESsetG0;
2180                         return;
2181                 case ')':
2182                         vc->vc_state = ESsetG1;
2183                         return;
2184                 case '#':
2185                         vc->vc_state = EShash;
2186                         return;
2187                 case 'c':
2188                         reset_terminal(vc, 1);
2189                         return;
2190                 case '>':  /* Numeric keypad */
2191                         clr_kbd(vc, kbdapplic);
2192                         return;
2193                 case '=':  /* Appl. keypad */
2194                         set_kbd(vc, kbdapplic);
2195                         return;
2196                 }
2197                 return;
2198         case ESnonstd:
2199                 if (c=='P') {   /* palette escape sequence */
2200                         for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2201                                 vc->vc_par[vc->vc_npar] = 0;
2202                         vc->vc_npar = 0;
2203                         vc->vc_state = ESpalette;
2204                         return;
2205                 } else if (c=='R') {   /* reset palette */
2206                         reset_palette(vc);
2207                         vc->vc_state = ESnormal;
2208                 } else if (c>='0' && c<='9')
2209                         vc->vc_state = ESosc;
2210                 else
2211                         vc->vc_state = ESnormal;
2212                 return;
2213         case ESpalette:
2214                 if (isxdigit(c)) {
2215                         vc->vc_par[vc->vc_npar++] = hex_to_bin(c);
2216                         if (vc->vc_npar == 7) {
2217                                 int i = vc->vc_par[0] * 3, j = 1;
2218                                 vc->vc_palette[i] = 16 * vc->vc_par[j++];
2219                                 vc->vc_palette[i++] += vc->vc_par[j++];
2220                                 vc->vc_palette[i] = 16 * vc->vc_par[j++];
2221                                 vc->vc_palette[i++] += vc->vc_par[j++];
2222                                 vc->vc_palette[i] = 16 * vc->vc_par[j++];
2223                                 vc->vc_palette[i] += vc->vc_par[j];
2224                                 set_palette(vc);
2225                                 vc->vc_state = ESnormal;
2226                         }
2227                 } else
2228                         vc->vc_state = ESnormal;
2229                 return;
2230         case ESsquare:
2231                 for (vc->vc_npar = 0; vc->vc_npar < NPAR; vc->vc_npar++)
2232                         vc->vc_par[vc->vc_npar] = 0;
2233                 vc->vc_npar = 0;
2234                 vc->vc_state = ESgetpars;
2235                 if (c == '[') { /* Function key */
2236                         vc->vc_state=ESfunckey;
2237                         return;
2238                 }
2239                 vc->vc_ques = (c == '?');
2240                 if (vc->vc_ques)
2241                         return;
2242         case ESgetpars:
2243                 if (c == ';' && vc->vc_npar < NPAR - 1) {
2244                         vc->vc_npar++;
2245                         return;
2246                 } else if (c>='0' && c<='9') {
2247                         vc->vc_par[vc->vc_npar] *= 10;
2248                         vc->vc_par[vc->vc_npar] += c - '0';
2249                         return;
2250                 }
2251                 vc->vc_state = ESnormal;
2252                 switch(c) {
2253                 case 'h':
2254                         set_mode(vc, 1);
2255                         return;
2256                 case 'l':
2257                         set_mode(vc, 0);
2258                         return;
2259                 case 'c':
2260                         if (vc->vc_ques) {
2261                                 if (vc->vc_par[0])
2262                                         vc->vc_cursor_type = vc->vc_par[0] | (vc->vc_par[1] << 8) | (vc->vc_par[2] << 16);
2263                                 else
2264                                         vc->vc_cursor_type = cur_default;
2265                                 return;
2266                         }
2267                         break;
2268                 case 'm':
2269                         if (vc->vc_ques) {
2270                                 clear_selection();
2271                                 if (vc->vc_par[0])
2272                                         vc->vc_complement_mask = vc->vc_par[0] << 8 | vc->vc_par[1];
2273                                 else
2274                                         vc->vc_complement_mask = vc->vc_s_complement_mask;
2275                                 return;
2276                         }
2277                         break;
2278                 case 'n':
2279                         if (!vc->vc_ques) {
2280                                 if (vc->vc_par[0] == 5)
2281                                         status_report(tty);
2282                                 else if (vc->vc_par[0] == 6)
2283                                         cursor_report(vc, tty);
2284                         }
2285                         return;
2286                 }
2287                 if (vc->vc_ques) {
2288                         vc->vc_ques = 0;
2289                         return;
2290                 }
2291                 switch(c) {
2292                 case 'G': case '`':
2293                         if (vc->vc_par[0])
2294                                 vc->vc_par[0]--;
2295                         gotoxy(vc, vc->vc_par[0], vc->vc_y);
2296                         return;
2297                 case 'A':
2298                         if (!vc->vc_par[0])
2299                                 vc->vc_par[0]++;
2300                         gotoxy(vc, vc->vc_x, vc->vc_y - vc->vc_par[0]);
2301                         return;
2302                 case 'B': case 'e':
2303                         if (!vc->vc_par[0])
2304                                 vc->vc_par[0]++;
2305                         gotoxy(vc, vc->vc_x, vc->vc_y + vc->vc_par[0]);
2306                         return;
2307                 case 'C': case 'a':
2308                         if (!vc->vc_par[0])
2309                                 vc->vc_par[0]++;
2310                         gotoxy(vc, vc->vc_x + vc->vc_par[0], vc->vc_y);
2311                         return;
2312                 case 'D':
2313                         if (!vc->vc_par[0])
2314                                 vc->vc_par[0]++;
2315                         gotoxy(vc, vc->vc_x - vc->vc_par[0], vc->vc_y);
2316                         return;
2317                 case 'E':
2318                         if (!vc->vc_par[0])
2319                                 vc->vc_par[0]++;
2320                         gotoxy(vc, 0, vc->vc_y + vc->vc_par[0]);
2321                         return;
2322                 case 'F':
2323                         if (!vc->vc_par[0])
2324                                 vc->vc_par[0]++;
2325                         gotoxy(vc, 0, vc->vc_y - vc->vc_par[0]);
2326                         return;
2327                 case 'd':
2328                         if (vc->vc_par[0])
2329                                 vc->vc_par[0]--;
2330                         gotoxay(vc, vc->vc_x ,vc->vc_par[0]);
2331                         return;
2332                 case 'H': case 'f':
2333                         if (vc->vc_par[0])
2334                                 vc->vc_par[0]--;
2335                         if (vc->vc_par[1])
2336                                 vc->vc_par[1]--;
2337                         gotoxay(vc, vc->vc_par[1], vc->vc_par[0]);
2338                         return;
2339                 case 'J':
2340                         csi_J(vc, vc->vc_par[0]);
2341                         return;
2342                 case 'K':
2343                         csi_K(vc, vc->vc_par[0]);
2344                         return;
2345                 case 'L':
2346                         csi_L(vc, vc->vc_par[0]);
2347                         return;
2348                 case 'M':
2349                         csi_M(vc, vc->vc_par[0]);
2350                         return;
2351                 case 'P':
2352                         csi_P(vc, vc->vc_par[0]);
2353                         return;
2354                 case 'c':
2355                         if (!vc->vc_par[0])
2356                                 respond_ID(tty);
2357                         return;
2358                 case 'g':
2359                         if (!vc->vc_par[0])
2360                                 vc->vc_tab_stop[7 & (vc->vc_x >> 5)] &= ~(1 << (vc->vc_x & 31));
2361                         else if (vc->vc_par[0] == 3) {
2362                                 vc->vc_tab_stop[0] =
2363                                         vc->vc_tab_stop[1] =
2364                                         vc->vc_tab_stop[2] =
2365                                         vc->vc_tab_stop[3] =
2366                                         vc->vc_tab_stop[4] =
2367                                         vc->vc_tab_stop[5] =
2368                                         vc->vc_tab_stop[6] =
2369                                         vc->vc_tab_stop[7] = 0;
2370                         }
2371                         return;
2372                 case 'm':
2373                         csi_m(vc);
2374                         return;
2375                 case 'q': /* DECLL - but only 3 leds */
2376                         /* map 0,1,2,3 to 0,1,2,4 */
2377                         if (vc->vc_par[0] < 4)
2378                                 vt_set_led_state(vc->vc_num,
2379                                             (vc->vc_par[0] < 3) ? vc->vc_par[0] : 4);
2380                         return;
2381                 case 'r':
2382                         if (!vc->vc_par[0])
2383                                 vc->vc_par[0]++;
2384                         if (!vc->vc_par[1])
2385                                 vc->vc_par[1] = vc->vc_rows;
2386                         /* Minimum allowed region is 2 lines */
2387                         if (vc->vc_par[0] < vc->vc_par[1] &&
2388                             vc->vc_par[1] <= vc->vc_rows) {
2389                                 vc->vc_top = vc->vc_par[0] - 1;
2390                                 vc->vc_bottom = vc->vc_par[1];
2391                                 gotoxay(vc, 0, 0);
2392                         }
2393                         return;
2394                 case 's':
2395                         save_cur(vc);
2396                         return;
2397                 case 'u':
2398                         restore_cur(vc);
2399                         return;
2400                 case 'X':
2401                         csi_X(vc, vc->vc_par[0]);
2402                         return;
2403                 case '@':
2404                         csi_at(vc, vc->vc_par[0]);
2405                         return;
2406                 case ']': /* setterm functions */
2407                         setterm_command(vc);
2408                         return;
2409                 }
2410                 return;
2411         case ESpercent:
2412                 vc->vc_state = ESnormal;
2413                 switch (c) {
2414                 case '@':  /* defined in ISO 2022 */
2415                         vc->vc_utf = 0;
2416                         return;
2417                 case 'G':  /* prelim official escape code */
2418                 case '8':  /* retained for compatibility */
2419                         vc->vc_utf = 1;
2420                         return;
2421                 }
2422                 return;
2423         case ESfunckey:
2424                 vc->vc_state = ESnormal;
2425                 return;
2426         case EShash:
2427                 vc->vc_state = ESnormal;
2428                 if (c == '8') {
2429                         /* DEC screen alignment test. kludge :-) */
2430                         vc->vc_video_erase_char =
2431                                 (vc->vc_video_erase_char & 0xff00) | 'E';
2432                         csi_J(vc, 2);
2433                         vc->vc_video_erase_char =
2434                                 (vc->vc_video_erase_char & 0xff00) | ' ';
2435                         do_update_region(vc, vc->vc_origin, vc->vc_screenbuf_size / 2);
2436                 }
2437                 return;
2438         case ESsetG0:
2439                 if (c == '0')
2440                         vc->vc_G0_charset = GRAF_MAP;
2441                 else if (c == 'B')
2442                         vc->vc_G0_charset = LAT1_MAP;
2443                 else if (c == 'U')
2444                         vc->vc_G0_charset = IBMPC_MAP;
2445                 else if (c == 'K')
2446                         vc->vc_G0_charset = USER_MAP;
2447                 if (vc->vc_charset == 0)
2448                         vc->vc_translate = set_translate(vc->vc_G0_charset, vc);
2449                 vc->vc_state = ESnormal;
2450                 return;
2451         case ESsetG1:
2452                 if (c == '0')
2453                         vc->vc_G1_charset = GRAF_MAP;
2454                 else if (c == 'B')
2455                         vc->vc_G1_charset = LAT1_MAP;
2456                 else if (c == 'U')
2457                         vc->vc_G1_charset = IBMPC_MAP;
2458                 else if (c == 'K')
2459                         vc->vc_G1_charset = USER_MAP;
2460                 if (vc->vc_charset == 1)
2461                         vc->vc_translate = set_translate(vc->vc_G1_charset, vc);
2462                 vc->vc_state = ESnormal;
2463                 return;
2464         case ESosc:
2465                 return;
2466         default:
2467                 vc->vc_state = ESnormal;
2468         }
2469 }
2470
2471 /* is_double_width() is based on the wcwidth() implementation by
2472  * Markus Kuhn -- 2007-05-26 (Unicode 5.0)
2473  * Latest version: http://www.cl.cam.ac.uk/~mgk25/ucs/wcwidth.c
2474  */
2475 struct interval {
2476         uint32_t first;
2477         uint32_t last;
2478 };
2479
2480 static int ucs_cmp(const void *key, const void *elt)
2481 {
2482         uint32_t ucs = *(uint32_t *)key;
2483         struct interval e = *(struct interval *) elt;
2484
2485         if (ucs > e.last)
2486                 return 1;
2487         else if (ucs < e.first)
2488                 return -1;
2489         return 0;
2490 }
2491
2492 static int is_double_width(uint32_t ucs)
2493 {
2494         static const struct interval double_width[] = {
2495                 { 0x1100, 0x115F }, { 0x2329, 0x232A }, { 0x2E80, 0x303E },
2496                 { 0x3040, 0xA4CF }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF },
2497                 { 0xFE10, 0xFE19 }, { 0xFE30, 0xFE6F }, { 0xFF00, 0xFF60 },
2498                 { 0xFFE0, 0xFFE6 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }
2499         };
2500         if (ucs < double_width[0].first ||
2501             ucs > double_width[ARRAY_SIZE(double_width) - 1].last)
2502                 return 0;
2503
2504         return bsearch(&ucs, double_width, ARRAY_SIZE(double_width),
2505                         sizeof(struct interval), ucs_cmp) != NULL;
2506 }
2507
2508 static void con_flush(struct vc_data *vc, unsigned long draw_from,
2509                 unsigned long draw_to, int *draw_x)
2510 {
2511         if (*draw_x < 0)
2512                 return;
2513
2514         vc->vc_sw->con_putcs(vc, (u16 *)draw_from,
2515                         (u16 *)draw_to - (u16 *)draw_from, vc->vc_y, *draw_x);
2516         *draw_x = -1;
2517 }
2518
2519 /* acquires console_lock */
2520 static int do_con_write(struct tty_struct *tty, const unsigned char *buf, int count)
2521 {
2522         int c, next_c, tc, ok, n = 0, draw_x = -1;
2523         unsigned int currcons;
2524         unsigned long draw_from = 0, draw_to = 0;
2525         struct vc_data *vc;
2526         unsigned char vc_attr;
2527         struct vt_notifier_param param;
2528         uint8_t rescan;
2529         uint8_t inverse;
2530         uint8_t width;
2531         u16 himask, charmask;
2532
2533         if (in_interrupt())
2534                 return count;
2535
2536         might_sleep();
2537
2538         console_lock();
2539         vc = tty->driver_data;
2540         if (vc == NULL) {
2541                 pr_err("vt: argh, driver_data is NULL !\n");
2542                 console_unlock();
2543                 return 0;
2544         }
2545
2546         currcons = vc->vc_num;
2547         if (!vc_cons_allocated(currcons)) {
2548                 /* could this happen? */
2549                 pr_warn_once("con_write: tty %d not allocated\n", currcons+1);
2550                 console_unlock();
2551                 return 0;
2552         }
2553
2554         himask = vc->vc_hi_font_mask;
2555         charmask = himask ? 0x1ff : 0xff;
2556
2557         /* undraw cursor first */
2558         if (con_is_fg(vc))
2559                 hide_cursor(vc);
2560
2561         param.vc = vc;
2562
2563         while (!tty->stopped && count) {
2564                 int orig = *buf;
2565                 c = orig;
2566                 buf++;
2567                 n++;
2568                 count--;
2569                 rescan = 0;
2570                 inverse = 0;
2571                 width = 1;
2572
2573                 /* Do no translation at all in control states */
2574                 if (vc->vc_state != ESnormal) {
2575                         tc = c;
2576                 } else if (vc->vc_utf && !vc->vc_disp_ctrl) {
2577                     /* Combine UTF-8 into Unicode in vc_utf_char.
2578                      * vc_utf_count is the number of continuation bytes still
2579                      * expected to arrive.
2580                      * vc_npar is the number of continuation bytes arrived so
2581                      * far
2582                      */
2583 rescan_last_byte:
2584                     if ((c & 0xc0) == 0x80) {
2585                         /* Continuation byte received */
2586                         static const uint32_t utf8_length_changes[] = { 0x0000007f, 0x000007ff, 0x0000ffff, 0x001fffff, 0x03ffffff, 0x7fffffff };
2587                         if (vc->vc_utf_count) {
2588                             vc->vc_utf_char = (vc->vc_utf_char << 6) | (c & 0x3f);
2589                             vc->vc_npar++;
2590                             if (--vc->vc_utf_count) {
2591                                 /* Still need some bytes */
2592                                 continue;
2593                             }
2594                             /* Got a whole character */
2595                             c = vc->vc_utf_char;
2596                             /* Reject overlong sequences */
2597                             if (c <= utf8_length_changes[vc->vc_npar - 1] ||
2598                                         c > utf8_length_changes[vc->vc_npar])
2599                                 c = 0xfffd;
2600                         } else {
2601                             /* Unexpected continuation byte */
2602                             vc->vc_utf_count = 0;
2603                             c = 0xfffd;
2604                         }
2605                     } else {
2606                         /* Single ASCII byte or first byte of a sequence received */
2607                         if (vc->vc_utf_count) {
2608                             /* Continuation byte expected */
2609                             rescan = 1;
2610                             vc->vc_utf_count = 0;
2611                             c = 0xfffd;
2612                         } else if (c > 0x7f) {
2613                             /* First byte of a multibyte sequence received */
2614                             vc->vc_npar = 0;
2615                             if ((c & 0xe0) == 0xc0) {
2616                                 vc->vc_utf_count = 1;
2617                                 vc->vc_utf_char = (c & 0x1f);
2618                             } else if ((c & 0xf0) == 0xe0) {
2619                                 vc->vc_utf_count = 2;
2620                                 vc->vc_utf_char = (c & 0x0f);
2621                             } else if ((c & 0xf8) == 0xf0) {
2622                                 vc->vc_utf_count = 3;
2623                                 vc->vc_utf_char = (c & 0x07);
2624                             } else if ((c & 0xfc) == 0xf8) {
2625                                 vc->vc_utf_count = 4;
2626                                 vc->vc_utf_char = (c & 0x03);
2627                             } else if ((c & 0xfe) == 0xfc) {
2628                                 vc->vc_utf_count = 5;
2629                                 vc->vc_utf_char = (c & 0x01);
2630                             } else {
2631                                 /* 254 and 255 are invalid */
2632                                 c = 0xfffd;
2633                             }
2634                             if (vc->vc_utf_count) {
2635                                 /* Still need some bytes */
2636                                 continue;
2637                             }
2638                         }
2639                         /* Nothing to do if an ASCII byte was received */
2640                     }
2641                     /* End of UTF-8 decoding. */
2642                     /* c is the received character, or U+FFFD for invalid sequences. */
2643                     /* Replace invalid Unicode code points with U+FFFD too */
2644                     if ((c >= 0xd800 && c <= 0xdfff) || c == 0xfffe || c == 0xffff)
2645                         c = 0xfffd;
2646                     tc = c;
2647                 } else {        /* no utf or alternate charset mode */
2648                     tc = vc_translate(vc, c);
2649                 }
2650
2651                 param.c = tc;
2652                 if (atomic_notifier_call_chain(&vt_notifier_list, VT_PREWRITE,
2653                                         &param) == NOTIFY_STOP)
2654                         continue;
2655
2656                 /* If the original code was a control character we
2657                  * only allow a glyph to be displayed if the code is
2658                  * not normally used (such as for cursor movement) or
2659                  * if the disp_ctrl mode has been explicitly enabled.
2660                  * Certain characters (as given by the CTRL_ALWAYS
2661                  * bitmap) are always displayed as control characters,
2662                  * as the console would be pretty useless without
2663                  * them; to display an arbitrary font position use the
2664                  * direct-to-font zone in UTF-8 mode.
2665                  */
2666                 ok = tc && (c >= 32 ||
2667                             !(vc->vc_disp_ctrl ? (CTRL_ALWAYS >> c) & 1 :
2668                                   vc->vc_utf || ((CTRL_ACTION >> c) & 1)))
2669                         && (c != 127 || vc->vc_disp_ctrl)
2670                         && (c != 128+27);
2671
2672                 if (vc->vc_state == ESnormal && ok) {
2673                         if (vc->vc_utf && !vc->vc_disp_ctrl) {
2674                                 if (is_double_width(c))
2675                                         width = 2;
2676                         }
2677                         /* Now try to find out how to display it */
2678                         tc = conv_uni_to_pc(vc, tc);
2679                         if (tc & ~charmask) {
2680                                 if (tc == -1 || tc == -2) {
2681                                     continue; /* nothing to display */
2682                                 }
2683                                 /* Glyph not found */
2684                                 if ((!(vc->vc_utf && !vc->vc_disp_ctrl) || c < 128) && !(c & ~charmask)) {
2685                                     /* In legacy mode use the glyph we get by a 1:1 mapping.
2686                                        This would make absolutely no sense with Unicode in mind,
2687                                        but do this for ASCII characters since a font may lack
2688                                        Unicode mapping info and we don't want to end up with
2689                                        having question marks only. */
2690                                     tc = c;
2691                                 } else {
2692                                     /* Display U+FFFD. If it's not found, display an inverse question mark. */
2693                                     tc = conv_uni_to_pc(vc, 0xfffd);
2694                                     if (tc < 0) {
2695                                         inverse = 1;
2696                                         tc = conv_uni_to_pc(vc, '?');
2697                                         if (tc < 0) tc = '?';
2698                                     }
2699                                 }
2700                         }
2701
2702                         if (!inverse) {
2703                                 vc_attr = vc->vc_attr;
2704                         } else {
2705                                 /* invert vc_attr */
2706                                 if (!vc->vc_can_do_color) {
2707                                         vc_attr = (vc->vc_attr) ^ 0x08;
2708                                 } else if (vc->vc_hi_font_mask == 0x100) {
2709                                         vc_attr = ((vc->vc_attr) & 0x11) | (((vc->vc_attr) & 0xe0) >> 4) | (((vc->vc_attr) & 0x0e) << 4);
2710                                 } else {
2711                                         vc_attr = ((vc->vc_attr) & 0x88) | (((vc->vc_attr) & 0x70) >> 4) | (((vc->vc_attr) & 0x07) << 4);
2712                                 }
2713                                 con_flush(vc, draw_from, draw_to, &draw_x);
2714                         }
2715
2716                         next_c = c;
2717                         while (1) {
2718                                 if (vc->vc_need_wrap || vc->vc_decim)
2719                                         con_flush(vc, draw_from, draw_to,
2720                                                         &draw_x);
2721                                 if (vc->vc_need_wrap) {
2722                                         cr(vc);
2723                                         lf(vc);
2724                                 }
2725                                 if (vc->vc_decim)
2726                                         insert_char(vc, 1);
2727                                 vc_uniscr_putc(vc, next_c);
2728                                 scr_writew(himask ?
2729                                              ((vc_attr << 8) & ~himask) + ((tc & 0x100) ? himask : 0) + (tc & 0xff) :
2730                                              (vc_attr << 8) + tc,
2731                                            (u16 *) vc->vc_pos);
2732                                 if (con_should_update(vc) && draw_x < 0) {
2733                                         draw_x = vc->vc_x;
2734                                         draw_from = vc->vc_pos;
2735                                 }
2736                                 if (vc->vc_x == vc->vc_cols - 1) {
2737                                         vc->vc_need_wrap = vc->vc_decawm;
2738                                         draw_to = vc->vc_pos + 2;
2739                                 } else {
2740                                         vc->vc_x++;
2741                                         draw_to = (vc->vc_pos += 2);
2742                                 }
2743
2744                                 if (!--width) break;
2745
2746                                 tc = conv_uni_to_pc(vc, ' '); /* A space is printed in the second column */
2747                                 if (tc < 0) tc = ' ';
2748                                 next_c = ' ';
2749                         }
2750                         notify_write(vc, c);
2751
2752                         if (inverse)
2753                                 con_flush(vc, draw_from, draw_to, &draw_x);
2754
2755                         if (rescan) {
2756                                 rescan = 0;
2757                                 inverse = 0;
2758                                 width = 1;
2759                                 c = orig;
2760                                 goto rescan_last_byte;
2761                         }
2762                         continue;
2763                 }
2764                 con_flush(vc, draw_from, draw_to, &draw_x);
2765                 do_con_trol(tty, vc, orig);
2766         }
2767         con_flush(vc, draw_from, draw_to, &draw_x);
2768         vc_uniscr_debug_check(vc);
2769         console_conditional_schedule();
2770         console_unlock();
2771         notify_update(vc);
2772         return n;
2773 }
2774
2775 /*
2776  * This is the console switching callback.
2777  *
2778  * Doing console switching in a process context allows
2779  * us to do the switches asynchronously (needed when we want
2780  * to switch due to a keyboard interrupt).  Synchronization
2781  * with other console code and prevention of re-entrancy is
2782  * ensured with console_lock.
2783  */
2784 static void console_callback(struct work_struct *ignored)
2785 {
2786         console_lock();
2787
2788         if (want_console >= 0) {
2789                 if (want_console != fg_console &&
2790                     vc_cons_allocated(want_console)) {
2791                         hide_cursor(vc_cons[fg_console].d);
2792                         change_console(vc_cons[want_console].d);
2793                         /* we only changed when the console had already
2794                            been allocated - a new console is not created
2795                            in an interrupt routine */
2796                 }
2797                 want_console = -1;
2798         }
2799         if (do_poke_blanked_console) { /* do not unblank for a LED change */
2800                 do_poke_blanked_console = 0;
2801                 poke_blanked_console();
2802         }
2803         if (scrollback_delta) {
2804                 struct vc_data *vc = vc_cons[fg_console].d;
2805                 clear_selection();
2806                 if (vc->vc_mode == KD_TEXT && vc->vc_sw->con_scrolldelta)
2807                         vc->vc_sw->con_scrolldelta(vc, scrollback_delta);
2808                 scrollback_delta = 0;
2809         }
2810         if (blank_timer_expired) {
2811                 do_blank_screen(0);
2812                 blank_timer_expired = 0;
2813         }
2814         notify_update(vc_cons[fg_console].d);
2815
2816         console_unlock();
2817 }
2818
2819 int set_console(int nr)
2820 {
2821         struct vc_data *vc = vc_cons[fg_console].d;
2822
2823         if (!vc_cons_allocated(nr) || vt_dont_switch ||
2824                 (vc->vt_mode.mode == VT_AUTO && vc->vc_mode == KD_GRAPHICS)) {
2825
2826                 /*
2827                  * Console switch will fail in console_callback() or
2828                  * change_console() so there is no point scheduling
2829                  * the callback
2830                  *
2831                  * Existing set_console() users don't check the return
2832                  * value so this shouldn't break anything
2833                  */
2834                 return -EINVAL;
2835         }
2836
2837         want_console = nr;
2838         schedule_console_callback();
2839
2840         return 0;
2841 }
2842
2843 struct tty_driver *console_driver;
2844
2845 #ifdef CONFIG_VT_CONSOLE
2846
2847 /**
2848  * vt_kmsg_redirect() - Sets/gets the kernel message console
2849  * @new:        The new virtual terminal number or -1 if the console should stay
2850  *              unchanged
2851  *
2852  * By default, the kernel messages are always printed on the current virtual
2853  * console. However, the user may modify that default with the
2854  * TIOCL_SETKMSGREDIRECT ioctl call.
2855  *
2856  * This function sets the kernel message console to be @new. It returns the old
2857  * virtual console number. The virtual terminal number 0 (both as parameter and
2858  * return value) means no redirection (i.e. always printed on the currently
2859  * active console).
2860  *
2861  * The parameter -1 means that only the current console is returned, but the
2862  * value is not modified. You may use the macro vt_get_kmsg_redirect() in that
2863  * case to make the code more understandable.
2864  *
2865  * When the kernel is compiled without CONFIG_VT_CONSOLE, this function ignores
2866  * the parameter and always returns 0.
2867  */
2868 int vt_kmsg_redirect(int new)
2869 {
2870         static int kmsg_con;
2871
2872         if (new != -1)
2873                 return xchg(&kmsg_con, new);
2874         else
2875                 return kmsg_con;
2876 }
2877
2878 /*
2879  *      Console on virtual terminal
2880  *
2881  * The console must be locked when we get here.
2882  */
2883
2884 static void vt_console_print(struct console *co, const char *b, unsigned count)
2885 {
2886         struct vc_data *vc = vc_cons[fg_console].d;
2887         unsigned char c;
2888         static DEFINE_SPINLOCK(printing_lock);
2889         const ushort *start;
2890         ushort cnt = 0;
2891         ushort myx;
2892         int kmsg_console;
2893
2894         /* console busy or not yet initialized */
2895         if (!printable)
2896                 return;
2897         if (!spin_trylock(&printing_lock))
2898                 return;
2899
2900         kmsg_console = vt_get_kmsg_redirect();
2901         if (kmsg_console && vc_cons_allocated(kmsg_console - 1))
2902                 vc = vc_cons[kmsg_console - 1].d;
2903
2904         /* read `x' only after setting currcons properly (otherwise
2905            the `x' macro will read the x of the foreground console). */
2906         myx = vc->vc_x;
2907
2908         if (!vc_cons_allocated(fg_console)) {
2909                 /* impossible */
2910                 /* printk("vt_console_print: tty %d not allocated ??\n", currcons+1); */
2911                 goto quit;
2912         }
2913
2914         if (vc->vc_mode != KD_TEXT && !vt_force_oops_output(vc))
2915                 goto quit;
2916
2917         /* undraw cursor first */
2918         if (con_is_fg(vc))
2919                 hide_cursor(vc);
2920
2921         start = (ushort *)vc->vc_pos;
2922
2923         /* Contrived structure to try to emulate original need_wrap behaviour
2924          * Problems caused when we have need_wrap set on '\n' character */
2925         while (count--) {
2926                 c = *b++;
2927                 if (c == 10 || c == 13 || c == 8 || vc->vc_need_wrap) {
2928                         if (cnt > 0) {
2929                                 if (con_is_visible(vc))
2930                                         vc->vc_sw->con_putcs(vc, start, cnt, vc->vc_y, vc->vc_x);
2931                                 vc->vc_x += cnt;
2932                                 if (vc->vc_need_wrap)
2933                                         vc->vc_x--;
2934                                 cnt = 0;
2935                         }
2936                         if (c == 8) {           /* backspace */
2937                                 bs(vc);
2938                                 start = (ushort *)vc->vc_pos;
2939                                 myx = vc->vc_x;
2940                                 continue;
2941                         }
2942                         if (c != 13)
2943                                 lf(vc);
2944                         cr(vc);
2945                         start = (ushort *)vc->vc_pos;
2946                         myx = vc->vc_x;
2947                         if (c == 10 || c == 13)
2948                                 continue;
2949                 }
2950                 scr_writew((vc->vc_attr << 8) + c, (unsigned short *)vc->vc_pos);
2951                 notify_write(vc, c);
2952                 cnt++;
2953                 if (myx == vc->vc_cols - 1) {
2954                         vc->vc_need_wrap = 1;
2955                         continue;
2956                 }
2957                 vc->vc_pos += 2;
2958                 myx++;
2959         }
2960         if (cnt > 0) {
2961                 if (con_is_visible(vc))
2962                         vc->vc_sw->con_putcs(vc, start, cnt, vc->vc_y, vc->vc_x);
2963                 vc->vc_x += cnt;
2964                 if (vc->vc_x == vc->vc_cols) {
2965                         vc->vc_x--;
2966                         vc->vc_need_wrap = 1;
2967                 }
2968         }
2969         set_cursor(vc);
2970         notify_update(vc);
2971
2972 quit:
2973         spin_unlock(&printing_lock);
2974 }
2975
2976 static struct tty_driver *vt_console_device(struct console *c, int *index)
2977 {
2978         *index = c->index ? c->index-1 : fg_console;
2979         return console_driver;
2980 }
2981
2982 static struct console vt_console_driver = {
2983         .name           = "tty",
2984         .write          = vt_console_print,
2985         .device         = vt_console_device,
2986         .unblank        = unblank_screen,
2987         .flags          = CON_PRINTBUFFER,
2988         .index          = -1,
2989 };
2990 #endif
2991
2992 /*
2993  *      Handling of Linux-specific VC ioctls
2994  */
2995
2996 /*
2997  * Generally a bit racy with respect to console_lock();.
2998  *
2999  * There are some functions which don't need it.
3000  *
3001  * There are some functions which can sleep for arbitrary periods
3002  * (paste_selection) but we don't need the lock there anyway.
3003  *
3004  * set_selection has locking, and definitely needs it
3005  */
3006
3007 int tioclinux(struct tty_struct *tty, unsigned long arg)
3008 {
3009         char type, data;
3010         char __user *p = (char __user *)arg;
3011         int lines;
3012         int ret;
3013
3014         if (current->signal->tty != tty && !capable(CAP_SYS_ADMIN))
3015                 return -EPERM;
3016         if (get_user(type, p))
3017                 return -EFAULT;
3018         ret = 0;
3019
3020         switch (type)
3021         {
3022                 case TIOCL_SETSEL:
3023                         console_lock();
3024                         ret = set_selection((struct tiocl_selection __user *)(p+1), tty);
3025                         console_unlock();
3026                         break;
3027                 case TIOCL_PASTESEL:
3028                         ret = paste_selection(tty);
3029                         break;
3030                 case TIOCL_UNBLANKSCREEN:
3031                         console_lock();
3032                         unblank_screen();
3033                         console_unlock();
3034                         break;
3035                 case TIOCL_SELLOADLUT:
3036                         console_lock();
3037                         ret = sel_loadlut(p);
3038                         console_unlock();
3039                         break;
3040                 case TIOCL_GETSHIFTSTATE:
3041
3042         /*
3043          * Make it possible to react to Shift+Mousebutton.
3044          * Note that 'shift_state' is an undocumented
3045          * kernel-internal variable; programs not closely
3046          * related to the kernel should not use this.
3047          */
3048                         data = vt_get_shift_state();
3049                         ret = put_user(data, p);
3050                         break;
3051                 case TIOCL_GETMOUSEREPORTING:
3052                         console_lock(); /* May be overkill */
3053                         data = mouse_reporting();
3054                         console_unlock();
3055                         ret = put_user(data, p);
3056                         break;
3057                 case TIOCL_SETVESABLANK:
3058                         console_lock();
3059                         ret = set_vesa_blanking(p);
3060                         console_unlock();
3061                         break;
3062                 case TIOCL_GETKMSGREDIRECT:
3063                         data = vt_get_kmsg_redirect();
3064                         ret = put_user(data, p);
3065                         break;
3066                 case TIOCL_SETKMSGREDIRECT:
3067                         if (!capable(CAP_SYS_ADMIN)) {
3068                                 ret = -EPERM;
3069                         } else {
3070                                 if (get_user(data, p+1))
3071                                         ret = -EFAULT;
3072                                 else
3073                                         vt_kmsg_redirect(data);
3074                         }
3075                         break;
3076                 case TIOCL_GETFGCONSOLE:
3077                         /* No locking needed as this is a transiently
3078                            correct return anyway if the caller hasn't
3079                            disabled switching */
3080                         ret = fg_console;
3081                         break;
3082                 case TIOCL_SCROLLCONSOLE:
3083                         if (get_user(lines, (s32 __user *)(p+4))) {
3084                                 ret = -EFAULT;
3085                         } else {
3086                                 /* Need the console lock here. Note that lots
3087                                    of other calls need fixing before the lock
3088                                    is actually useful ! */
3089                                 console_lock();
3090                                 scrollfront(vc_cons[fg_console].d, lines);
3091                                 console_unlock();
3092                                 ret = 0;
3093                         }
3094                         break;
3095                 case TIOCL_BLANKSCREEN: /* until explicitly unblanked, not only poked */
3096                         console_lock();
3097                         ignore_poke = 1;
3098                         do_blank_screen(0);
3099                         console_unlock();
3100                         break;