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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/char/vt_ioctl.c
Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/char/vt_ioctl.c')
-rw-r--r--drivers/char/vt_ioctl.c1201
1 files changed, 1201 insertions, 0 deletions
diff --git a/drivers/char/vt_ioctl.c b/drivers/char/vt_ioctl.c
new file mode 100644
index 000000000000..5d386f4bea49
--- /dev/null
+++ b/drivers/char/vt_ioctl.c
@@ -0,0 +1,1201 @@
1/*
2 * linux/drivers/char/vt_ioctl.c
3 *
4 * Copyright (C) 1992 obz under the linux copyright
5 *
6 * Dynamic diacritical handling - aeb@cwi.nl - Dec 1993
7 * Dynamic keymap and string allocation - aeb@cwi.nl - May 1994
8 * Restrict VT switching via ioctl() - grif@cs.ucr.edu - Dec 1995
9 * Some code moved for less code duplication - Andi Kleen - Mar 1997
10 * Check put/get_user, cleanups - acme@conectiva.com.br - Jun 2001
11 */
12
13#include <linux/config.h>
14#include <linux/types.h>
15#include <linux/errno.h>
16#include <linux/sched.h>
17#include <linux/tty.h>
18#include <linux/timer.h>
19#include <linux/kernel.h>
20#include <linux/kd.h>
21#include <linux/vt.h>
22#include <linux/string.h>
23#include <linux/slab.h>
24#include <linux/major.h>
25#include <linux/fs.h>
26#include <linux/console.h>
27
28#include <asm/io.h>
29#include <asm/uaccess.h>
30
31#include <linux/kbd_kern.h>
32#include <linux/vt_kern.h>
33#include <linux/kbd_diacr.h>
34#include <linux/selection.h>
35
36static char vt_dont_switch;
37extern struct tty_driver *console_driver;
38
39#define VT_IS_IN_USE(i) (console_driver->ttys[i] && console_driver->ttys[i]->count)
40#define VT_BUSY(i) (VT_IS_IN_USE(i) || i == fg_console || vc_cons[i].d == sel_cons)
41
42/*
43 * Console (vt and kd) routines, as defined by USL SVR4 manual, and by
44 * experimentation and study of X386 SYSV handling.
45 *
46 * One point of difference: SYSV vt's are /dev/vtX, which X >= 0, and
47 * /dev/console is a separate ttyp. Under Linux, /dev/tty0 is /dev/console,
48 * and the vc start at /dev/ttyX, X >= 1. We maintain that here, so we will
49 * always treat our set of vt as numbered 1..MAX_NR_CONSOLES (corresponding to
50 * ttys 0..MAX_NR_CONSOLES-1). Explicitly naming VT 0 is illegal, but using
51 * /dev/tty0 (fg_console) as a target is legal, since an implicit aliasing
52 * to the current console is done by the main ioctl code.
53 */
54
55#ifdef CONFIG_X86
56#include <linux/syscalls.h>
57#endif
58
59static void complete_change_console(struct vc_data *vc);
60
61/*
62 * these are the valid i/o ports we're allowed to change. they map all the
63 * video ports
64 */
65#define GPFIRST 0x3b4
66#define GPLAST 0x3df
67#define GPNUM (GPLAST - GPFIRST + 1)
68
69#define i (tmp.kb_index)
70#define s (tmp.kb_table)
71#define v (tmp.kb_value)
72static inline int
73do_kdsk_ioctl(int cmd, struct kbentry __user *user_kbe, int perm, struct kbd_struct *kbd)
74{
75 struct kbentry tmp;
76 ushort *key_map, val, ov;
77
78 if (copy_from_user(&tmp, user_kbe, sizeof(struct kbentry)))
79 return -EFAULT;
80
81 switch (cmd) {
82 case KDGKBENT:
83 key_map = key_maps[s];
84 if (key_map) {
85 val = U(key_map[i]);
86 if (kbd->kbdmode != VC_UNICODE && KTYP(val) >= NR_TYPES)
87 val = K_HOLE;
88 } else
89 val = (i ? K_HOLE : K_NOSUCHMAP);
90 return put_user(val, &user_kbe->kb_value);
91 case KDSKBENT:
92 if (!perm)
93 return -EPERM;
94 if (!i && v == K_NOSUCHMAP) {
95 /* disallocate map */
96 key_map = key_maps[s];
97 if (s && key_map) {
98 key_maps[s] = NULL;
99 if (key_map[0] == U(K_ALLOCATED)) {
100 kfree(key_map);
101 keymap_count--;
102 }
103 }
104 break;
105 }
106
107 if (KTYP(v) < NR_TYPES) {
108 if (KVAL(v) > max_vals[KTYP(v)])
109 return -EINVAL;
110 } else
111 if (kbd->kbdmode != VC_UNICODE)
112 return -EINVAL;
113
114 /* ++Geert: non-PC keyboards may generate keycode zero */
115#if !defined(__mc68000__) && !defined(__powerpc__)
116 /* assignment to entry 0 only tests validity of args */
117 if (!i)
118 break;
119#endif
120
121 if (!(key_map = key_maps[s])) {
122 int j;
123
124 if (keymap_count >= MAX_NR_OF_USER_KEYMAPS &&
125 !capable(CAP_SYS_RESOURCE))
126 return -EPERM;
127
128 key_map = (ushort *) kmalloc(sizeof(plain_map),
129 GFP_KERNEL);
130 if (!key_map)
131 return -ENOMEM;
132 key_maps[s] = key_map;
133 key_map[0] = U(K_ALLOCATED);
134 for (j = 1; j < NR_KEYS; j++)
135 key_map[j] = U(K_HOLE);
136 keymap_count++;
137 }
138 ov = U(key_map[i]);
139 if (v == ov)
140 break; /* nothing to do */
141 /*
142 * Attention Key.
143 */
144 if (((ov == K_SAK) || (v == K_SAK)) && !capable(CAP_SYS_ADMIN))
145 return -EPERM;
146 key_map[i] = U(v);
147 if (!s && (KTYP(ov) == KT_SHIFT || KTYP(v) == KT_SHIFT))
148 compute_shiftstate();
149 break;
150 }
151 return 0;
152}
153#undef i
154#undef s
155#undef v
156
157static inline int
158do_kbkeycode_ioctl(int cmd, struct kbkeycode __user *user_kbkc, int perm)
159{
160 struct kbkeycode tmp;
161 int kc = 0;
162
163 if (copy_from_user(&tmp, user_kbkc, sizeof(struct kbkeycode)))
164 return -EFAULT;
165 switch (cmd) {
166 case KDGETKEYCODE:
167 kc = getkeycode(tmp.scancode);
168 if (kc >= 0)
169 kc = put_user(kc, &user_kbkc->keycode);
170 break;
171 case KDSETKEYCODE:
172 if (!perm)
173 return -EPERM;
174 kc = setkeycode(tmp.scancode, tmp.keycode);
175 break;
176 }
177 return kc;
178}
179
180static inline int
181do_kdgkb_ioctl(int cmd, struct kbsentry __user *user_kdgkb, int perm)
182{
183 struct kbsentry *kbs;
184 char *p;
185 u_char *q;
186 u_char __user *up;
187 int sz;
188 int delta;
189 char *first_free, *fj, *fnw;
190 int i, j, k;
191 int ret;
192
193 kbs = kmalloc(sizeof(*kbs), GFP_KERNEL);
194 if (!kbs) {
195 ret = -ENOMEM;
196 goto reterr;
197 }
198
199 /* we mostly copy too much here (512bytes), but who cares ;) */
200 if (copy_from_user(kbs, user_kdgkb, sizeof(struct kbsentry))) {
201 ret = -EFAULT;
202 goto reterr;
203 }
204 kbs->kb_string[sizeof(kbs->kb_string)-1] = '\0';
205 i = kbs->kb_func;
206
207 switch (cmd) {
208 case KDGKBSENT:
209 sz = sizeof(kbs->kb_string) - 1; /* sz should have been
210 a struct member */
211 up = user_kdgkb->kb_string;
212 p = func_table[i];
213 if(p)
214 for ( ; *p && sz; p++, sz--)
215 if (put_user(*p, up++)) {
216 ret = -EFAULT;
217 goto reterr;
218 }
219 if (put_user('\0', up)) {
220 ret = -EFAULT;
221 goto reterr;
222 }
223 kfree(kbs);
224 return ((p && *p) ? -EOVERFLOW : 0);
225 case KDSKBSENT:
226 if (!perm) {
227 ret = -EPERM;
228 goto reterr;
229 }
230
231 q = func_table[i];
232 first_free = funcbufptr + (funcbufsize - funcbufleft);
233 for (j = i+1; j < MAX_NR_FUNC && !func_table[j]; j++)
234 ;
235 if (j < MAX_NR_FUNC)
236 fj = func_table[j];
237 else
238 fj = first_free;
239
240 delta = (q ? -strlen(q) : 1) + strlen(kbs->kb_string);
241 if (delta <= funcbufleft) { /* it fits in current buf */
242 if (j < MAX_NR_FUNC) {
243 memmove(fj + delta, fj, first_free - fj);
244 for (k = j; k < MAX_NR_FUNC; k++)
245 if (func_table[k])
246 func_table[k] += delta;
247 }
248 if (!q)
249 func_table[i] = fj;
250 funcbufleft -= delta;
251 } else { /* allocate a larger buffer */
252 sz = 256;
253 while (sz < funcbufsize - funcbufleft + delta)
254 sz <<= 1;
255 fnw = (char *) kmalloc(sz, GFP_KERNEL);
256 if(!fnw) {
257 ret = -ENOMEM;
258 goto reterr;
259 }
260
261 if (!q)
262 func_table[i] = fj;
263 if (fj > funcbufptr)
264 memmove(fnw, funcbufptr, fj - funcbufptr);
265 for (k = 0; k < j; k++)
266 if (func_table[k])
267 func_table[k] = fnw + (func_table[k] - funcbufptr);
268
269 if (first_free > fj) {
270 memmove(fnw + (fj - funcbufptr) + delta, fj, first_free - fj);
271 for (k = j; k < MAX_NR_FUNC; k++)
272 if (func_table[k])
273 func_table[k] = fnw + (func_table[k] - funcbufptr) + delta;
274 }
275 if (funcbufptr != func_buf)
276 kfree(funcbufptr);
277 funcbufptr = fnw;
278 funcbufleft = funcbufleft - delta + sz - funcbufsize;
279 funcbufsize = sz;
280 }
281 strcpy(func_table[i], kbs->kb_string);
282 break;
283 }
284 ret = 0;
285reterr:
286 kfree(kbs);
287 return ret;
288}
289
290static inline int
291do_fontx_ioctl(int cmd, struct consolefontdesc __user *user_cfd, int perm, struct console_font_op *op)
292{
293 struct consolefontdesc cfdarg;
294 int i;
295
296 if (copy_from_user(&cfdarg, user_cfd, sizeof(struct consolefontdesc)))
297 return -EFAULT;
298
299 switch (cmd) {
300 case PIO_FONTX:
301 if (!perm)
302 return -EPERM;
303 op->op = KD_FONT_OP_SET;
304 op->flags = KD_FONT_FLAG_OLD;
305 op->width = 8;
306 op->height = cfdarg.charheight;
307 op->charcount = cfdarg.charcount;
308 op->data = cfdarg.chardata;
309 return con_font_op(vc_cons[fg_console].d, op);
310 case GIO_FONTX: {
311 op->op = KD_FONT_OP_GET;
312 op->flags = KD_FONT_FLAG_OLD;
313 op->width = 8;
314 op->height = cfdarg.charheight;
315 op->charcount = cfdarg.charcount;
316 op->data = cfdarg.chardata;
317 i = con_font_op(vc_cons[fg_console].d, op);
318 if (i)
319 return i;
320 cfdarg.charheight = op->height;
321 cfdarg.charcount = op->charcount;
322 if (copy_to_user(user_cfd, &cfdarg, sizeof(struct consolefontdesc)))
323 return -EFAULT;
324 return 0;
325 }
326 }
327 return -EINVAL;
328}
329
330static inline int
331do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud, int perm, struct vc_data *vc)
332{
333 struct unimapdesc tmp;
334
335 if (copy_from_user(&tmp, user_ud, sizeof tmp))
336 return -EFAULT;
337 if (tmp.entries)
338 if (!access_ok(VERIFY_WRITE, tmp.entries,
339 tmp.entry_ct*sizeof(struct unipair)))
340 return -EFAULT;
341 switch (cmd) {
342 case PIO_UNIMAP:
343 if (!perm)
344 return -EPERM;
345 return con_set_unimap(vc, tmp.entry_ct, tmp.entries);
346 case GIO_UNIMAP:
347 if (!perm && fg_console != vc->vc_num)
348 return -EPERM;
349 return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp.entries);
350 }
351 return 0;
352}
353
354/*
355 * We handle the console-specific ioctl's here. We allow the
356 * capability to modify any console, not just the fg_console.
357 */
358int vt_ioctl(struct tty_struct *tty, struct file * file,
359 unsigned int cmd, unsigned long arg)
360{
361 struct vc_data *vc = (struct vc_data *)tty->driver_data;
362 struct console_font_op op; /* used in multiple places here */
363 struct kbd_struct * kbd;
364 unsigned int console;
365 unsigned char ucval;
366 void __user *up = (void __user *)arg;
367 int i, perm;
368
369 console = vc->vc_num;
370
371 if (!vc_cons_allocated(console)) /* impossible? */
372 return -ENOIOCTLCMD;
373
374 /*
375 * To have permissions to do most of the vt ioctls, we either have
376 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
377 */
378 perm = 0;
379 if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
380 perm = 1;
381
382 kbd = kbd_table + console;
383 switch (cmd) {
384 case KIOCSOUND:
385 if (!perm)
386 return -EPERM;
387 if (arg)
388 arg = 1193182 / arg;
389 kd_mksound(arg, 0);
390 return 0;
391
392 case KDMKTONE:
393 if (!perm)
394 return -EPERM;
395 {
396 unsigned int ticks, count;
397
398 /*
399 * Generate the tone for the appropriate number of ticks.
400 * If the time is zero, turn off sound ourselves.
401 */
402 ticks = HZ * ((arg >> 16) & 0xffff) / 1000;
403 count = ticks ? (arg & 0xffff) : 0;
404 if (count)
405 count = 1193182 / count;
406 kd_mksound(count, ticks);
407 return 0;
408 }
409
410 case KDGKBTYPE:
411 /*
412 * this is naive.
413 */
414 ucval = KB_101;
415 goto setchar;
416
417 /*
418 * These cannot be implemented on any machine that implements
419 * ioperm() in user level (such as Alpha PCs) or not at all.
420 *
421 * XXX: you should never use these, just call ioperm directly..
422 */
423#ifdef CONFIG_X86
424 case KDADDIO:
425 case KDDELIO:
426 /*
427 * KDADDIO and KDDELIO may be able to add ports beyond what
428 * we reject here, but to be safe...
429 */
430 if (arg < GPFIRST || arg > GPLAST)
431 return -EINVAL;
432 return sys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
433
434 case KDENABIO:
435 case KDDISABIO:
436 return sys_ioperm(GPFIRST, GPNUM,
437 (cmd == KDENABIO)) ? -ENXIO : 0;
438#endif
439
440 /* Linux m68k/i386 interface for setting the keyboard delay/repeat rate */
441
442 case KDKBDREP:
443 {
444 struct kbd_repeat kbrep;
445 int err;
446
447 if (!capable(CAP_SYS_TTY_CONFIG))
448 return -EPERM;
449
450 if (copy_from_user(&kbrep, up, sizeof(struct kbd_repeat)))
451 return -EFAULT;
452 err = kbd_rate(&kbrep);
453 if (err)
454 return err;
455 if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat)))
456 return -EFAULT;
457 return 0;
458 }
459
460 case KDSETMODE:
461 /*
462 * currently, setting the mode from KD_TEXT to KD_GRAPHICS
463 * doesn't do a whole lot. i'm not sure if it should do any
464 * restoration of modes or what...
465 *
466 * XXX It should at least call into the driver, fbdev's definitely
467 * need to restore their engine state. --BenH
468 */
469 if (!perm)
470 return -EPERM;
471 switch (arg) {
472 case KD_GRAPHICS:
473 break;
474 case KD_TEXT0:
475 case KD_TEXT1:
476 arg = KD_TEXT;
477 case KD_TEXT:
478 break;
479 default:
480 return -EINVAL;
481 }
482 if (vc->vc_mode == (unsigned char) arg)
483 return 0;
484 vc->vc_mode = (unsigned char) arg;
485 if (console != fg_console)
486 return 0;
487 /*
488 * explicitly blank/unblank the screen if switching modes
489 */
490 acquire_console_sem();
491 if (arg == KD_TEXT)
492 do_unblank_screen(1);
493 else
494 do_blank_screen(1);
495 release_console_sem();
496 return 0;
497
498 case KDGETMODE:
499 ucval = vc->vc_mode;
500 goto setint;
501
502 case KDMAPDISP:
503 case KDUNMAPDISP:
504 /*
505 * these work like a combination of mmap and KDENABIO.
506 * this could be easily finished.
507 */
508 return -EINVAL;
509
510 case KDSKBMODE:
511 if (!perm)
512 return -EPERM;
513 switch(arg) {
514 case K_RAW:
515 kbd->kbdmode = VC_RAW;
516 break;
517 case K_MEDIUMRAW:
518 kbd->kbdmode = VC_MEDIUMRAW;
519 break;
520 case K_XLATE:
521 kbd->kbdmode = VC_XLATE;
522 compute_shiftstate();
523 break;
524 case K_UNICODE:
525 kbd->kbdmode = VC_UNICODE;
526 compute_shiftstate();
527 break;
528 default:
529 return -EINVAL;
530 }
531 tty_ldisc_flush(tty);
532 return 0;
533
534 case KDGKBMODE:
535 ucval = ((kbd->kbdmode == VC_RAW) ? K_RAW :
536 (kbd->kbdmode == VC_MEDIUMRAW) ? K_MEDIUMRAW :
537 (kbd->kbdmode == VC_UNICODE) ? K_UNICODE :
538 K_XLATE);
539 goto setint;
540
541 /* this could be folded into KDSKBMODE, but for compatibility
542 reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
543 case KDSKBMETA:
544 switch(arg) {
545 case K_METABIT:
546 clr_vc_kbd_mode(kbd, VC_META);
547 break;
548 case K_ESCPREFIX:
549 set_vc_kbd_mode(kbd, VC_META);
550 break;
551 default:
552 return -EINVAL;
553 }
554 return 0;
555
556 case KDGKBMETA:
557 ucval = (vc_kbd_mode(kbd, VC_META) ? K_ESCPREFIX : K_METABIT);
558 setint:
559 return put_user(ucval, (int __user *)arg);
560
561 case KDGETKEYCODE:
562 case KDSETKEYCODE:
563 if(!capable(CAP_SYS_TTY_CONFIG))
564 perm=0;
565 return do_kbkeycode_ioctl(cmd, up, perm);
566
567 case KDGKBENT:
568 case KDSKBENT:
569 return do_kdsk_ioctl(cmd, up, perm, kbd);
570
571 case KDGKBSENT:
572 case KDSKBSENT:
573 return do_kdgkb_ioctl(cmd, up, perm);
574
575 case KDGKBDIACR:
576 {
577 struct kbdiacrs __user *a = up;
578
579 if (put_user(accent_table_size, &a->kb_cnt))
580 return -EFAULT;
581 if (copy_to_user(a->kbdiacr, accent_table, accent_table_size*sizeof(struct kbdiacr)))
582 return -EFAULT;
583 return 0;
584 }
585
586 case KDSKBDIACR:
587 {
588 struct kbdiacrs __user *a = up;
589 unsigned int ct;
590
591 if (!perm)
592 return -EPERM;
593 if (get_user(ct,&a->kb_cnt))
594 return -EFAULT;
595 if (ct >= MAX_DIACR)
596 return -EINVAL;
597 accent_table_size = ct;
598 if (copy_from_user(accent_table, a->kbdiacr, ct*sizeof(struct kbdiacr)))
599 return -EFAULT;
600 return 0;
601 }
602
603 /* the ioctls below read/set the flags usually shown in the leds */
604 /* don't use them - they will go away without warning */
605 case KDGKBLED:
606 ucval = kbd->ledflagstate | (kbd->default_ledflagstate << 4);
607 goto setchar;
608
609 case KDSKBLED:
610 if (!perm)
611 return -EPERM;
612 if (arg & ~0x77)
613 return -EINVAL;
614 kbd->ledflagstate = (arg & 7);
615 kbd->default_ledflagstate = ((arg >> 4) & 7);
616 set_leds();
617 return 0;
618
619 /* the ioctls below only set the lights, not the functions */
620 /* for those, see KDGKBLED and KDSKBLED above */
621 case KDGETLED:
622 ucval = getledstate();
623 setchar:
624 return put_user(ucval, (char __user *)arg);
625
626 case KDSETLED:
627 if (!perm)
628 return -EPERM;
629 setledstate(kbd, arg);
630 return 0;
631
632 /*
633 * A process can indicate its willingness to accept signals
634 * generated by pressing an appropriate key combination.
635 * Thus, one can have a daemon that e.g. spawns a new console
636 * upon a keypress and then changes to it.
637 * See also the kbrequest field of inittab(5).
638 */
639 case KDSIGACCEPT:
640 {
641 extern int spawnpid, spawnsig;
642 if (!perm || !capable(CAP_KILL))
643 return -EPERM;
644 if (arg < 1 || arg > _NSIG || arg == SIGKILL)
645 return -EINVAL;
646 spawnpid = current->pid;
647 spawnsig = arg;
648 return 0;
649 }
650
651 case VT_SETMODE:
652 {
653 struct vt_mode tmp;
654
655 if (!perm)
656 return -EPERM;
657 if (copy_from_user(&tmp, up, sizeof(struct vt_mode)))
658 return -EFAULT;
659 if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS)
660 return -EINVAL;
661 acquire_console_sem();
662 vc->vt_mode = tmp;
663 /* the frsig is ignored, so we set it to 0 */
664 vc->vt_mode.frsig = 0;
665 vc->vt_pid = current->pid;
666 /* no switch is required -- saw@shade.msu.ru */
667 vc->vt_newvt = -1;
668 release_console_sem();
669 return 0;
670 }
671
672 case VT_GETMODE:
673 {
674 struct vt_mode tmp;
675 int rc;
676
677 acquire_console_sem();
678 memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
679 release_console_sem();
680
681 rc = copy_to_user(up, &tmp, sizeof(struct vt_mode));
682 return rc ? -EFAULT : 0;
683 }
684
685 /*
686 * Returns global vt state. Note that VT 0 is always open, since
687 * it's an alias for the current VT, and people can't use it here.
688 * We cannot return state for more than 16 VTs, since v_state is short.
689 */
690 case VT_GETSTATE:
691 {
692 struct vt_stat __user *vtstat = up;
693 unsigned short state, mask;
694
695 if (put_user(fg_console + 1, &vtstat->v_active))
696 return -EFAULT;
697 state = 1; /* /dev/tty0 is always open */
698 for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask; ++i, mask <<= 1)
699 if (VT_IS_IN_USE(i))
700 state |= mask;
701 return put_user(state, &vtstat->v_state);
702 }
703
704 /*
705 * Returns the first available (non-opened) console.
706 */
707 case VT_OPENQRY:
708 for (i = 0; i < MAX_NR_CONSOLES; ++i)
709 if (! VT_IS_IN_USE(i))
710 break;
711 ucval = i < MAX_NR_CONSOLES ? (i+1) : -1;
712 goto setint;
713
714 /*
715 * ioctl(fd, VT_ACTIVATE, num) will cause us to switch to vt # num,
716 * with num >= 1 (switches to vt 0, our console, are not allowed, just
717 * to preserve sanity).
718 */
719 case VT_ACTIVATE:
720 if (!perm)
721 return -EPERM;
722 if (arg == 0 || arg > MAX_NR_CONSOLES)
723 return -ENXIO;
724 arg--;
725 acquire_console_sem();
726 i = vc_allocate(arg);
727 release_console_sem();
728 if (i)
729 return i;
730 set_console(arg);
731 return 0;
732
733 /*
734 * wait until the specified VT has been activated
735 */
736 case VT_WAITACTIVE:
737 if (!perm)
738 return -EPERM;
739 if (arg == 0 || arg > MAX_NR_CONSOLES)
740 return -ENXIO;
741 return vt_waitactive(arg-1);
742
743 /*
744 * If a vt is under process control, the kernel will not switch to it
745 * immediately, but postpone the operation until the process calls this
746 * ioctl, allowing the switch to complete.
747 *
748 * According to the X sources this is the behavior:
749 * 0: pending switch-from not OK
750 * 1: pending switch-from OK
751 * 2: completed switch-to OK
752 */
753 case VT_RELDISP:
754 if (!perm)
755 return -EPERM;
756 if (vc->vt_mode.mode != VT_PROCESS)
757 return -EINVAL;
758
759 /*
760 * Switching-from response
761 */
762 if (vc->vt_newvt >= 0) {
763 if (arg == 0)
764 /*
765 * Switch disallowed, so forget we were trying
766 * to do it.
767 */
768 vc->vt_newvt = -1;
769
770 else {
771 /*
772 * The current vt has been released, so
773 * complete the switch.
774 */
775 int newvt;
776 acquire_console_sem();
777 newvt = vc->vt_newvt;
778 vc->vt_newvt = -1;
779 i = vc_allocate(newvt);
780 if (i) {
781 release_console_sem();
782 return i;
783 }
784 /*
785 * When we actually do the console switch,
786 * make sure we are atomic with respect to
787 * other console switches..
788 */
789 complete_change_console(vc_cons[newvt].d);
790 release_console_sem();
791 }
792 }
793
794 /*
795 * Switched-to response
796 */
797 else
798 {
799 /*
800 * If it's just an ACK, ignore it
801 */
802 if (arg != VT_ACKACQ)
803 return -EINVAL;
804 }
805
806 return 0;
807
808 /*
809 * Disallocate memory associated to VT (but leave VT1)
810 */
811 case VT_DISALLOCATE:
812 if (arg > MAX_NR_CONSOLES)
813 return -ENXIO;
814 if (arg == 0) {
815 /* disallocate all unused consoles, but leave 0 */
816 acquire_console_sem();
817 for (i=1; i<MAX_NR_CONSOLES; i++)
818 if (! VT_BUSY(i))
819 vc_disallocate(i);
820 release_console_sem();
821 } else {
822 /* disallocate a single console, if possible */
823 arg--;
824 if (VT_BUSY(arg))
825 return -EBUSY;
826 if (arg) { /* leave 0 */
827 acquire_console_sem();
828 vc_disallocate(arg);
829 release_console_sem();
830 }
831 }
832 return 0;
833
834 case VT_RESIZE:
835 {
836 struct vt_sizes __user *vtsizes = up;
837 ushort ll,cc;
838 if (!perm)
839 return -EPERM;
840 if (get_user(ll, &vtsizes->v_rows) ||
841 get_user(cc, &vtsizes->v_cols))
842 return -EFAULT;
843 for (i = 0; i < MAX_NR_CONSOLES; i++) {
844 acquire_console_sem();
845 vc_resize(vc_cons[i].d, cc, ll);
846 release_console_sem();
847 }
848 return 0;
849 }
850
851 case VT_RESIZEX:
852 {
853 struct vt_consize __user *vtconsize = up;
854 ushort ll,cc,vlin,clin,vcol,ccol;
855 if (!perm)
856 return -EPERM;
857 if (!access_ok(VERIFY_READ, vtconsize,
858 sizeof(struct vt_consize)))
859 return -EFAULT;
860 __get_user(ll, &vtconsize->v_rows);
861 __get_user(cc, &vtconsize->v_cols);
862 __get_user(vlin, &vtconsize->v_vlin);
863 __get_user(clin, &vtconsize->v_clin);
864 __get_user(vcol, &vtconsize->v_vcol);
865 __get_user(ccol, &vtconsize->v_ccol);
866 vlin = vlin ? vlin : vc->vc_scan_lines;
867 if (clin) {
868 if (ll) {
869 if (ll != vlin/clin)
870 return -EINVAL; /* Parameters don't add up */
871 } else
872 ll = vlin/clin;
873 }
874 if (vcol && ccol) {
875 if (cc) {
876 if (cc != vcol/ccol)
877 return -EINVAL;
878 } else
879 cc = vcol/ccol;
880 }
881
882 if (clin > 32)
883 return -EINVAL;
884
885 for (i = 0; i < MAX_NR_CONSOLES; i++) {
886 if (!vc_cons[i].d)
887 continue;
888 acquire_console_sem();
889 if (vlin)
890 vc_cons[i].d->vc_scan_lines = vlin;
891 if (clin)
892 vc_cons[i].d->vc_font.height = clin;
893 vc_resize(vc_cons[i].d, cc, ll);
894 release_console_sem();
895 }
896 return 0;
897 }
898
899 case PIO_FONT: {
900 if (!perm)
901 return -EPERM;
902 op.op = KD_FONT_OP_SET;
903 op.flags = KD_FONT_FLAG_OLD | KD_FONT_FLAG_DONT_RECALC; /* Compatibility */
904 op.width = 8;
905 op.height = 0;
906 op.charcount = 256;
907 op.data = up;
908 return con_font_op(vc_cons[fg_console].d, &op);
909 }
910
911 case GIO_FONT: {
912 op.op = KD_FONT_OP_GET;
913 op.flags = KD_FONT_FLAG_OLD;
914 op.width = 8;
915 op.height = 32;
916 op.charcount = 256;
917 op.data = up;
918 return con_font_op(vc_cons[fg_console].d, &op);
919 }
920
921 case PIO_CMAP:
922 if (!perm)
923 return -EPERM;
924 return con_set_cmap(up);
925
926 case GIO_CMAP:
927 return con_get_cmap(up);
928
929 case PIO_FONTX:
930 case GIO_FONTX:
931 return do_fontx_ioctl(cmd, up, perm, &op);
932
933 case PIO_FONTRESET:
934 {
935 if (!perm)
936 return -EPERM;
937
938#ifdef BROKEN_GRAPHICS_PROGRAMS
939 /* With BROKEN_GRAPHICS_PROGRAMS defined, the default
940 font is not saved. */
941 return -ENOSYS;
942#else
943 {
944 op.op = KD_FONT_OP_SET_DEFAULT;
945 op.data = NULL;
946 i = con_font_op(vc_cons[fg_console].d, &op);
947 if (i)
948 return i;
949 con_set_default_unimap(vc_cons[fg_console].d);
950 return 0;
951 }
952#endif
953 }
954
955 case KDFONTOP: {
956 if (copy_from_user(&op, up, sizeof(op)))
957 return -EFAULT;
958 if (!perm && op.op != KD_FONT_OP_GET)
959 return -EPERM;
960 i = con_font_op(vc, &op);
961 if (i) return i;
962 if (copy_to_user(up, &op, sizeof(op)))
963 return -EFAULT;
964 return 0;
965 }
966
967 case PIO_SCRNMAP:
968 if (!perm)
969 return -EPERM;
970 return con_set_trans_old(up);
971
972 case GIO_SCRNMAP:
973 return con_get_trans_old(up);
974
975 case PIO_UNISCRNMAP:
976 if (!perm)
977 return -EPERM;
978 return con_set_trans_new(up);
979
980 case GIO_UNISCRNMAP:
981 return con_get_trans_new(up);
982
983 case PIO_UNIMAPCLR:
984 { struct unimapinit ui;
985 if (!perm)
986 return -EPERM;
987 i = copy_from_user(&ui, up, sizeof(struct unimapinit));
988 if (i) return -EFAULT;
989 con_clear_unimap(vc, &ui);
990 return 0;
991 }
992
993 case PIO_UNIMAP:
994 case GIO_UNIMAP:
995 return do_unimap_ioctl(cmd, up, perm, vc);
996
997 case VT_LOCKSWITCH:
998 if (!capable(CAP_SYS_TTY_CONFIG))
999 return -EPERM;
1000 vt_dont_switch = 1;
1001 return 0;
1002 case VT_UNLOCKSWITCH:
1003 if (!capable(CAP_SYS_TTY_CONFIG))
1004 return -EPERM;
1005 vt_dont_switch = 0;
1006 return 0;
1007 default:
1008 return -ENOIOCTLCMD;
1009 }
1010}
1011
1012/*
1013 * Sometimes we want to wait until a particular VT has been activated. We
1014 * do it in a very simple manner. Everybody waits on a single queue and
1015 * get woken up at once. Those that are satisfied go on with their business,
1016 * while those not ready go back to sleep. Seems overkill to add a wait
1017 * to each vt just for this - usually this does nothing!
1018 */
1019static DECLARE_WAIT_QUEUE_HEAD(vt_activate_queue);
1020
1021/*
1022 * Sleeps until a vt is activated, or the task is interrupted. Returns
1023 * 0 if activation, -EINTR if interrupted.
1024 */
1025int vt_waitactive(int vt)
1026{
1027 int retval;
1028 DECLARE_WAITQUEUE(wait, current);
1029
1030 add_wait_queue(&vt_activate_queue, &wait);
1031 for (;;) {
1032 set_current_state(TASK_INTERRUPTIBLE);
1033 retval = 0;
1034 if (vt == fg_console)
1035 break;
1036 retval = -EINTR;
1037 if (signal_pending(current))
1038 break;
1039 schedule();
1040 }
1041 remove_wait_queue(&vt_activate_queue, &wait);
1042 current->state = TASK_RUNNING;
1043 return retval;
1044}
1045
1046#define vt_wake_waitactive() wake_up(&vt_activate_queue)
1047
1048void reset_vc(struct vc_data *vc)
1049{
1050 vc->vc_mode = KD_TEXT;
1051 kbd_table[vc->vc_num].kbdmode = VC_XLATE;
1052 vc->vt_mode.mode = VT_AUTO;
1053 vc->vt_mode.waitv = 0;
1054 vc->vt_mode.relsig = 0;
1055 vc->vt_mode.acqsig = 0;
1056 vc->vt_mode.frsig = 0;
1057 vc->vt_pid = -1;
1058 vc->vt_newvt = -1;
1059 if (!in_interrupt()) /* Via keyboard.c:SAK() - akpm */
1060 reset_palette(vc);
1061}
1062
1063/*
1064 * Performs the back end of a vt switch
1065 */
1066static void complete_change_console(struct vc_data *vc)
1067{
1068 unsigned char old_vc_mode;
1069
1070 last_console = fg_console;
1071
1072 /*
1073 * If we're switching, we could be going from KD_GRAPHICS to
1074 * KD_TEXT mode or vice versa, which means we need to blank or
1075 * unblank the screen later.
1076 */
1077 old_vc_mode = vc_cons[fg_console].d->vc_mode;
1078 switch_screen(vc);
1079
1080 /*
1081 * This can't appear below a successful kill_proc(). If it did,
1082 * then the *blank_screen operation could occur while X, having
1083 * received acqsig, is waking up on another processor. This
1084 * condition can lead to overlapping accesses to the VGA range
1085 * and the framebuffer (causing system lockups).
1086 *
1087 * To account for this we duplicate this code below only if the
1088 * controlling process is gone and we've called reset_vc.
1089 */
1090 if (old_vc_mode != vc->vc_mode) {
1091 if (vc->vc_mode == KD_TEXT)
1092 do_unblank_screen(1);
1093 else
1094 do_blank_screen(1);
1095 }
1096
1097 /*
1098 * If this new console is under process control, send it a signal
1099 * telling it that it has acquired. Also check if it has died and
1100 * clean up (similar to logic employed in change_console())
1101 */
1102 if (vc->vt_mode.mode == VT_PROCESS) {
1103 /*
1104 * Send the signal as privileged - kill_proc() will
1105 * tell us if the process has gone or something else
1106 * is awry
1107 */
1108 if (kill_proc(vc->vt_pid, vc->vt_mode.acqsig, 1) != 0) {
1109 /*
1110 * The controlling process has died, so we revert back to
1111 * normal operation. In this case, we'll also change back
1112 * to KD_TEXT mode. I'm not sure if this is strictly correct
1113 * but it saves the agony when the X server dies and the screen
1114 * remains blanked due to KD_GRAPHICS! It would be nice to do
1115 * this outside of VT_PROCESS but there is no single process
1116 * to account for and tracking tty count may be undesirable.
1117 */
1118 reset_vc(vc);
1119
1120 if (old_vc_mode != vc->vc_mode) {
1121 if (vc->vc_mode == KD_TEXT)
1122 do_unblank_screen(1);
1123 else
1124 do_blank_screen(1);
1125 }
1126 }
1127 }
1128
1129 /*
1130 * Wake anyone waiting for their VT to activate
1131 */
1132 vt_wake_waitactive();
1133 return;
1134}
1135
1136/*
1137 * Performs the front-end of a vt switch
1138 */
1139void change_console(struct vc_data *new_vc)
1140{
1141 struct vc_data *vc;
1142
1143 if (!new_vc || new_vc->vc_num == fg_console || vt_dont_switch)
1144 return;
1145
1146 /*
1147 * If this vt is in process mode, then we need to handshake with
1148 * that process before switching. Essentially, we store where that
1149 * vt wants to switch to and wait for it to tell us when it's done
1150 * (via VT_RELDISP ioctl).
1151 *
1152 * We also check to see if the controlling process still exists.
1153 * If it doesn't, we reset this vt to auto mode and continue.
1154 * This is a cheap way to track process control. The worst thing
1155 * that can happen is: we send a signal to a process, it dies, and
1156 * the switch gets "lost" waiting for a response; hopefully, the
1157 * user will try again, we'll detect the process is gone (unless
1158 * the user waits just the right amount of time :-) and revert the
1159 * vt to auto control.
1160 */
1161 vc = vc_cons[fg_console].d;
1162 if (vc->vt_mode.mode == VT_PROCESS) {
1163 /*
1164 * Send the signal as privileged - kill_proc() will
1165 * tell us if the process has gone or something else
1166 * is awry
1167 */
1168 if (kill_proc(vc->vt_pid, vc->vt_mode.relsig, 1) == 0) {
1169 /*
1170 * It worked. Mark the vt to switch to and
1171 * return. The process needs to send us a
1172 * VT_RELDISP ioctl to complete the switch.
1173 */
1174 vc->vt_newvt = new_vc->vc_num;
1175 return;
1176 }
1177
1178 /*
1179 * The controlling process has died, so we revert back to
1180 * normal operation. In this case, we'll also change back
1181 * to KD_TEXT mode. I'm not sure if this is strictly correct
1182 * but it saves the agony when the X server dies and the screen
1183 * remains blanked due to KD_GRAPHICS! It would be nice to do
1184 * this outside of VT_PROCESS but there is no single process
1185 * to account for and tracking tty count may be undesirable.
1186 */
1187 reset_vc(vc);
1188
1189 /*
1190 * Fall through to normal (VT_AUTO) handling of the switch...
1191 */
1192 }
1193
1194 /*
1195 * Ignore all switches in KD_GRAPHICS+VT_AUTO mode
1196 */
1197 if (vc->vc_mode == KD_GRAPHICS)
1198 return;
1199
1200 complete_change_console(new_vc);
1201}
generated by cgit v1.2.2 (git 2.25.0) at 2024-12-22 21:06:13 -0500