1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 1992 obz under the linux copyright
5 * Dynamic diacritical handling - aeb@cwi.nl - Dec 1993
6 * Dynamic keymap and string allocation - aeb@cwi.nl - May 1994
7 * Restrict VT switching via ioctl() - grif@cs.ucr.edu - Dec 1995
8 * Some code moved for less code duplication - Andi Kleen - Mar 1997
9 * Check put/get_user, cleanups - acme@conectiva.com.br - Jun 2001
12 #include <linux/types.h>
13 #include <linux/errno.h>
14 #include <linux/sched/signal.h>
15 #include <linux/tty.h>
16 #include <linux/timer.h>
17 #include <linux/kernel.h>
18 #include <linux/compat.h>
19 #include <linux/module.h>
22 #include <linux/string.h>
23 #include <linux/slab.h>
24 #include <linux/major.h>
26 #include <linux/console.h>
27 #include <linux/consolemap.h>
28 #include <linux/signal.h>
29 #include <linux/suspend.h>
30 #include <linux/timex.h>
33 #include <linux/uaccess.h>
35 #include <linux/kbd_kern.h>
36 #include <linux/vt_kern.h>
37 #include <linux/kbd_diacr.h>
38 #include <linux/selection.h>
41 extern struct tty_driver *console_driver;
43 #define VT_IS_IN_USE(i) (console_driver->ttys[i] && console_driver->ttys[i]->count)
44 #define VT_BUSY(i) (VT_IS_IN_USE(i) || i == fg_console || vc_cons[i].d == sel_cons)
47 * Console (vt and kd) routines, as defined by USL SVR4 manual, and by
48 * experimentation and study of X386 SYSV handling.
50 * One point of difference: SYSV vt's are /dev/vtX, which X >= 0, and
51 * /dev/console is a separate ttyp. Under Linux, /dev/tty0 is /dev/console,
52 * and the vc start at /dev/ttyX, X >= 1. We maintain that here, so we will
53 * always treat our set of vt as numbered 1..MAX_NR_CONSOLES (corresponding to
54 * ttys 0..MAX_NR_CONSOLES-1). Explicitly naming VT 0 is illegal, but using
55 * /dev/tty0 (fg_console) as a target is legal, since an implicit aliasing
56 * to the current console is done by the main ioctl code.
60 #include <linux/syscalls.h>
63 static void complete_change_console(struct vc_data *vc);
66 * User space VT_EVENT handlers
69 struct vt_event_wait {
70 struct list_head list;
71 struct vt_event event;
75 static LIST_HEAD(vt_events);
76 static DEFINE_SPINLOCK(vt_event_lock);
77 static DECLARE_WAIT_QUEUE_HEAD(vt_event_waitqueue);
81 * @event: the event that occurred
85 * Post an VT event to interested VT handlers
88 void vt_event_post(unsigned int event, unsigned int old, unsigned int new)
90 struct list_head *pos, *head;
94 spin_lock_irqsave(&vt_event_lock, flags);
97 list_for_each(pos, head) {
98 struct vt_event_wait *ve = list_entry(pos,
99 struct vt_event_wait, list);
100 if (!(ve->event.event & event))
102 ve->event.event = event;
103 /* kernel view is consoles 0..n-1, user space view is
104 console 1..n with 0 meaning current, so we must bias */
105 ve->event.oldev = old + 1;
106 ve->event.newev = new + 1;
110 spin_unlock_irqrestore(&vt_event_lock, flags);
112 wake_up_interruptible(&vt_event_waitqueue);
115 static void __vt_event_queue(struct vt_event_wait *vw)
118 /* Prepare the event */
119 INIT_LIST_HEAD(&vw->list);
121 /* Queue our event */
122 spin_lock_irqsave(&vt_event_lock, flags);
123 list_add(&vw->list, &vt_events);
124 spin_unlock_irqrestore(&vt_event_lock, flags);
127 static void __vt_event_wait(struct vt_event_wait *vw)
129 /* Wait for it to pass */
130 wait_event_interruptible(vt_event_waitqueue, vw->done);
133 static void __vt_event_dequeue(struct vt_event_wait *vw)
138 spin_lock_irqsave(&vt_event_lock, flags);
140 spin_unlock_irqrestore(&vt_event_lock, flags);
144 * vt_event_wait - wait for an event
147 * Waits for an event to occur which completes our vt_event_wait
148 * structure. On return the structure has wv->done set to 1 for success
149 * or 0 if some event such as a signal ended the wait.
152 static void vt_event_wait(struct vt_event_wait *vw)
154 __vt_event_queue(vw);
156 __vt_event_dequeue(vw);
160 * vt_event_wait_ioctl - event ioctl handler
161 * @arg: argument to ioctl
163 * Implement the VT_WAITEVENT ioctl using the VT event interface
166 static int vt_event_wait_ioctl(struct vt_event __user *event)
168 struct vt_event_wait vw;
170 if (copy_from_user(&vw.event, event, sizeof(struct vt_event)))
172 /* Highest supported event for now */
173 if (vw.event.event & ~VT_MAX_EVENT)
177 /* If it occurred report it */
179 if (copy_to_user(event, &vw.event, sizeof(struct vt_event)))
187 * vt_waitactive - active console wait
191 * Helper for event waits. Used to implement the legacy
192 * event waiting ioctls in terms of events
195 int vt_waitactive(int n)
197 struct vt_event_wait vw;
199 vw.event.event = VT_EVENT_SWITCH;
200 __vt_event_queue(&vw);
201 if (n == fg_console + 1) {
202 __vt_event_dequeue(&vw);
205 __vt_event_wait(&vw);
206 __vt_event_dequeue(&vw);
209 } while (vw.event.newev != n);
214 * these are the valid i/o ports we're allowed to change. they map all the
217 #define GPFIRST 0x3b4
219 #define GPNUM (GPLAST - GPFIRST + 1)
224 do_fontx_ioctl(int cmd, struct consolefontdesc __user *user_cfd, int perm, struct console_font_op *op)
226 struct consolefontdesc cfdarg;
229 if (copy_from_user(&cfdarg, user_cfd, sizeof(struct consolefontdesc)))
236 op->op = KD_FONT_OP_SET;
237 op->flags = KD_FONT_FLAG_OLD;
239 op->height = cfdarg.charheight;
240 op->charcount = cfdarg.charcount;
241 op->data = cfdarg.chardata;
242 return con_font_op(vc_cons[fg_console].d, op);
244 op->op = KD_FONT_OP_GET;
245 op->flags = KD_FONT_FLAG_OLD;
247 op->height = cfdarg.charheight;
248 op->charcount = cfdarg.charcount;
249 op->data = cfdarg.chardata;
250 i = con_font_op(vc_cons[fg_console].d, op);
253 cfdarg.charheight = op->height;
254 cfdarg.charcount = op->charcount;
255 if (copy_to_user(user_cfd, &cfdarg, sizeof(struct consolefontdesc)))
264 do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud, int perm, struct vc_data *vc)
266 struct unimapdesc tmp;
268 if (copy_from_user(&tmp, user_ud, sizeof tmp))
274 return con_set_unimap(vc, tmp.entry_ct, tmp.entries);
276 if (!perm && fg_console != vc->vc_num)
278 return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp.entries);
283 /* deallocate a single console, if possible (leave 0) */
284 static int vt_disallocate(unsigned int vc_num)
286 struct vc_data *vc = NULL;
293 vc = vc_deallocate(vc_num);
296 if (vc && vc_num >= MIN_NR_CONSOLES) {
297 tty_port_destroy(&vc->port);
304 /* deallocate all unused consoles, but leave 0 */
305 static void vt_disallocate_all(void)
307 struct vc_data *vc[MAX_NR_CONSOLES];
311 for (i = 1; i < MAX_NR_CONSOLES; i++)
313 vc[i] = vc_deallocate(i);
318 for (i = 1; i < MAX_NR_CONSOLES; i++) {
319 if (vc[i] && i >= MIN_NR_CONSOLES) {
320 tty_port_destroy(&vc[i]->port);
328 * We handle the console-specific ioctl's here. We allow the
329 * capability to modify any console, not just the fg_console.
331 int vt_ioctl(struct tty_struct *tty,
332 unsigned int cmd, unsigned long arg)
334 struct vc_data *vc = tty->driver_data;
335 struct console_font_op op; /* used in multiple places here */
336 unsigned int console;
339 void __user *up = (void __user *)arg;
343 console = vc->vc_num;
346 if (!vc_cons_allocated(console)) { /* impossible? */
353 * To have permissions to do most of the vt ioctls, we either have
354 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
357 if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
362 ret = tioclinux(tty, arg);
368 * The use of PIT_TICK_RATE is historic, it used to be
369 * the platform-dependent CLOCK_TICK_RATE between 2.6.12
370 * and 2.6.36, which was a minor but unfortunate ABI
371 * change. kd_mksound is locked by the input layer.
374 arg = PIT_TICK_RATE / arg;
382 unsigned int ticks, count;
385 * Generate the tone for the appropriate number of ticks.
386 * If the time is zero, turn off sound ourselves.
388 ticks = msecs_to_jiffies((arg >> 16) & 0xffff);
389 count = ticks ? (arg & 0xffff) : 0;
391 count = PIT_TICK_RATE / count;
392 kd_mksound(count, ticks);
401 ret = put_user(ucval, (char __user *)arg);
405 * These cannot be implemented on any machine that implements
406 * ioperm() in user level (such as Alpha PCs) or not at all.
408 * XXX: you should never use these, just call ioperm directly..
414 * KDADDIO and KDDELIO may be able to add ports beyond what
415 * we reject here, but to be safe...
417 * These are locked internally via sys_ioperm
419 if (arg < GPFIRST || arg > GPLAST) {
423 ret = sys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
428 ret = sys_ioperm(GPFIRST, GPNUM,
429 (cmd == KDENABIO)) ? -ENXIO : 0;
433 /* Linux m68k/i386 interface for setting the keyboard delay/repeat rate */
437 struct kbd_repeat kbrep;
439 if (!capable(CAP_SYS_TTY_CONFIG))
442 if (copy_from_user(&kbrep, up, sizeof(struct kbd_repeat))) {
446 ret = kbd_rate(&kbrep);
449 if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat)))
456 * currently, setting the mode from KD_TEXT to KD_GRAPHICS
457 * doesn't do a whole lot. i'm not sure if it should do any
458 * restoration of modes or what...
460 * XXX It should at least call into the driver, fbdev's definitely
461 * need to restore their engine state. --BenH
477 /* FIXME: this needs the console lock extending */
478 if (vc->vc_mode == (unsigned char) arg)
480 vc->vc_mode = (unsigned char) arg;
481 if (console != fg_console)
484 * explicitly blank/unblank the screen if switching modes
488 do_unblank_screen(1);
501 * these work like a combination of mmap and KDENABIO.
502 * this could be easily finished.
510 ret = vt_do_kdskbmode(console, arg);
512 tty_ldisc_flush(tty);
516 uival = vt_do_kdgkbmode(console);
517 ret = put_user(uival, (int __user *)arg);
520 /* this could be folded into KDSKBMODE, but for compatibility
521 reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
523 ret = vt_do_kdskbmeta(console, arg);
527 /* FIXME: should review whether this is worth locking */
528 uival = vt_do_kdgkbmeta(console);
530 ret = put_user(uival, (int __user *)arg);
535 if(!capable(CAP_SYS_TTY_CONFIG))
537 ret = vt_do_kbkeycode_ioctl(cmd, up, perm);
542 ret = vt_do_kdsk_ioctl(cmd, up, perm, console);
547 ret = vt_do_kdgkb_ioctl(cmd, up, perm);
550 /* Diacritical processing. Handled in keyboard.c as it has
551 to operate on the keyboard locks and structures */
556 ret = vt_do_diacrit(cmd, up, perm);
559 /* the ioctls below read/set the flags usually shown in the leds */
560 /* don't use them - they will go away without warning */
565 ret = vt_do_kdskled(console, cmd, arg, perm);
569 * A process can indicate its willingness to accept signals
570 * generated by pressing an appropriate key combination.
571 * Thus, one can have a daemon that e.g. spawns a new console
572 * upon a keypress and then changes to it.
573 * See also the kbrequest field of inittab(5).
577 if (!perm || !capable(CAP_KILL))
579 if (!valid_signal(arg) || arg < 1 || arg == SIGKILL)
582 spin_lock_irq(&vt_spawn_con.lock);
583 put_pid(vt_spawn_con.pid);
584 vt_spawn_con.pid = get_pid(task_pid(current));
585 vt_spawn_con.sig = arg;
586 spin_unlock_irq(&vt_spawn_con.lock);
597 if (copy_from_user(&tmp, up, sizeof(struct vt_mode))) {
601 if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS) {
607 /* the frsig is ignored, so we set it to 0 */
608 vc->vt_mode.frsig = 0;
610 vc->vt_pid = get_pid(task_pid(current));
611 /* no switch is required -- saw@shade.msu.ru */
623 memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
626 rc = copy_to_user(up, &tmp, sizeof(struct vt_mode));
633 * Returns global vt state. Note that VT 0 is always open, since
634 * it's an alias for the current VT, and people can't use it here.
635 * We cannot return state for more than 16 VTs, since v_state is short.
639 struct vt_stat __user *vtstat = up;
640 unsigned short state, mask;
642 /* Review: FIXME: Console lock ? */
643 if (put_user(fg_console + 1, &vtstat->v_active))
646 state = 1; /* /dev/tty0 is always open */
647 for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
651 ret = put_user(state, &vtstat->v_state);
657 * Returns the first available (non-opened) console.
660 /* FIXME: locking ? - but then this is a stupid API */
661 for (i = 0; i < MAX_NR_CONSOLES; ++i)
662 if (! VT_IS_IN_USE(i))
664 uival = i < MAX_NR_CONSOLES ? (i+1) : -1;
668 * ioctl(fd, VT_ACTIVATE, num) will cause us to switch to vt # num,
669 * with num >= 1 (switches to vt 0, our console, are not allowed, just
670 * to preserve sanity).
675 if (arg == 0 || arg > MAX_NR_CONSOLES)
680 ret = vc_allocate(arg);
690 struct vt_setactivate vsa;
695 if (copy_from_user(&vsa, (struct vt_setactivate __user *)arg,
696 sizeof(struct vt_setactivate))) {
700 if (vsa.console == 0 || vsa.console > MAX_NR_CONSOLES)
705 ret = vc_allocate(vsa.console);
708 /* This is safe providing we don't drop the
709 console sem between vc_allocate and
710 finishing referencing nvc */
711 nvc = vc_cons[vsa.console].d;
712 nvc->vt_mode = vsa.mode;
713 nvc->vt_mode.frsig = 0;
714 put_pid(nvc->vt_pid);
715 nvc->vt_pid = get_pid(task_pid(current));
720 /* Commence switch and lock */
721 /* Review set_console locks */
722 set_console(vsa.console);
728 * wait until the specified VT has been activated
733 if (arg == 0 || arg > MAX_NR_CONSOLES)
736 ret = vt_waitactive(arg);
740 * If a vt is under process control, the kernel will not switch to it
741 * immediately, but postpone the operation until the process calls this
742 * ioctl, allowing the switch to complete.
744 * According to the X sources this is the behavior:
745 * 0: pending switch-from not OK
746 * 1: pending switch-from OK
747 * 2: completed switch-to OK
754 if (vc->vt_mode.mode != VT_PROCESS) {
760 * Switching-from response
762 if (vc->vt_newvt >= 0) {
765 * Switch disallowed, so forget we were trying
772 * The current vt has been released, so
773 * complete the switch.
776 newvt = vc->vt_newvt;
778 ret = vc_allocate(newvt);
784 * When we actually do the console switch,
785 * make sure we are atomic with respect to
786 * other console switches..
788 complete_change_console(vc_cons[newvt].d);
792 * Switched-to response
795 * If it's just an ACK, ignore it
797 if (arg != VT_ACKACQ)
804 * Disallocate memory associated to VT (but leave VT1)
807 if (arg > MAX_NR_CONSOLES) {
812 vt_disallocate_all();
814 ret = vt_disallocate(--arg);
819 struct vt_sizes __user *vtsizes = up;
825 if (get_user(ll, &vtsizes->v_rows) ||
826 get_user(cc, &vtsizes->v_cols))
830 for (i = 0; i < MAX_NR_CONSOLES; i++) {
834 vc->vc_resize_user = 1;
835 /* FIXME: review v tty lock */
836 vc_resize(vc_cons[i].d, cc, ll);
846 struct vt_consize __user *vtconsize = up;
847 ushort ll,cc,vlin,clin,vcol,ccol;
850 if (!access_ok(VERIFY_READ, vtconsize,
851 sizeof(struct vt_consize))) {
855 /* FIXME: Should check the copies properly */
856 __get_user(ll, &vtconsize->v_rows);
857 __get_user(cc, &vtconsize->v_cols);
858 __get_user(vlin, &vtconsize->v_vlin);
859 __get_user(clin, &vtconsize->v_clin);
860 __get_user(vcol, &vtconsize->v_vcol);
861 __get_user(ccol, &vtconsize->v_ccol);
862 vlin = vlin ? vlin : vc->vc_scan_lines;
865 if (ll != vlin/clin) {
866 /* Parameters don't add up */
875 if (cc != vcol/ccol) {
888 for (i = 0; i < MAX_NR_CONSOLES; i++) {
893 vc_cons[i].d->vc_scan_lines = vlin;
895 vc_cons[i].d->vc_font.height = clin;
896 vc_cons[i].d->vc_resize_user = 1;
897 vc_resize(vc_cons[i].d, cc, ll);
906 op.op = KD_FONT_OP_SET;
907 op.flags = KD_FONT_FLAG_OLD | KD_FONT_FLAG_DONT_RECALC; /* Compatibility */
912 ret = con_font_op(vc_cons[fg_console].d, &op);
917 op.op = KD_FONT_OP_GET;
918 op.flags = KD_FONT_FLAG_OLD;
923 ret = con_font_op(vc_cons[fg_console].d, &op);
931 ret = con_set_cmap(up);
935 ret = con_get_cmap(up);
940 ret = do_fontx_ioctl(cmd, up, perm, &op);
948 #ifdef BROKEN_GRAPHICS_PROGRAMS
949 /* With BROKEN_GRAPHICS_PROGRAMS defined, the default
950 font is not saved. */
955 op.op = KD_FONT_OP_SET_DEFAULT;
957 ret = con_font_op(vc_cons[fg_console].d, &op);
961 con_set_default_unimap(vc_cons[fg_console].d);
969 if (copy_from_user(&op, up, sizeof(op))) {
973 if (!perm && op.op != KD_FONT_OP_GET)
975 ret = con_font_op(vc, &op);
978 if (copy_to_user(up, &op, sizeof(op)))
987 ret = con_set_trans_old(up);
991 ret = con_get_trans_old(up);
998 ret = con_set_trans_new(up);
1001 case GIO_UNISCRNMAP:
1002 ret = con_get_trans_new(up);
1008 con_clear_unimap(vc);
1013 ret = do_unimap_ioctl(cmd, up, perm, vc);
1017 if (!capable(CAP_SYS_TTY_CONFIG))
1021 case VT_UNLOCKSWITCH:
1022 if (!capable(CAP_SYS_TTY_CONFIG))
1026 case VT_GETHIFONTMASK:
1027 ret = put_user(vc->vc_hi_font_mask,
1028 (unsigned short __user *)arg);
1031 ret = vt_event_wait_ioctl((struct vt_event __user *)arg);
1040 void reset_vc(struct vc_data *vc)
1042 vc->vc_mode = KD_TEXT;
1043 vt_reset_unicode(vc->vc_num);
1044 vc->vt_mode.mode = VT_AUTO;
1045 vc->vt_mode.waitv = 0;
1046 vc->vt_mode.relsig = 0;
1047 vc->vt_mode.acqsig = 0;
1048 vc->vt_mode.frsig = 0;
1049 put_pid(vc->vt_pid);
1052 if (!in_interrupt()) /* Via keyboard.c:SAK() - akpm */
1056 void vc_SAK(struct work_struct *work)
1059 container_of(work, struct vc, SAK_work);
1061 struct tty_struct *tty;
1066 /* FIXME: review tty ref counting */
1069 * SAK should also work in all raw modes and reset
1079 #ifdef CONFIG_COMPAT
1081 struct compat_consolefontdesc {
1082 unsigned short charcount; /* characters in font (256 or 512) */
1083 unsigned short charheight; /* scan lines per character (1-32) */
1084 compat_caddr_t chardata; /* font data in expanded form */
1088 compat_fontx_ioctl(int cmd, struct compat_consolefontdesc __user *user_cfd,
1089 int perm, struct console_font_op *op)
1091 struct compat_consolefontdesc cfdarg;
1094 if (copy_from_user(&cfdarg, user_cfd, sizeof(struct compat_consolefontdesc)))
1101 op->op = KD_FONT_OP_SET;
1102 op->flags = KD_FONT_FLAG_OLD;
1104 op->height = cfdarg.charheight;
1105 op->charcount = cfdarg.charcount;
1106 op->data = compat_ptr(cfdarg.chardata);
1107 return con_font_op(vc_cons[fg_console].d, op);
1109 op->op = KD_FONT_OP_GET;
1110 op->flags = KD_FONT_FLAG_OLD;
1112 op->height = cfdarg.charheight;
1113 op->charcount = cfdarg.charcount;
1114 op->data = compat_ptr(cfdarg.chardata);
1115 i = con_font_op(vc_cons[fg_console].d, op);
1118 cfdarg.charheight = op->height;
1119 cfdarg.charcount = op->charcount;
1120 if (copy_to_user(user_cfd, &cfdarg, sizeof(struct compat_consolefontdesc)))
1127 struct compat_console_font_op {
1128 compat_uint_t op; /* operation code KD_FONT_OP_* */
1129 compat_uint_t flags; /* KD_FONT_FLAG_* */
1130 compat_uint_t width, height; /* font size */
1131 compat_uint_t charcount;
1132 compat_caddr_t data; /* font data with height fixed to 32 */
1136 compat_kdfontop_ioctl(struct compat_console_font_op __user *fontop,
1137 int perm, struct console_font_op *op, struct vc_data *vc)
1141 if (copy_from_user(op, fontop, sizeof(struct compat_console_font_op)))
1143 if (!perm && op->op != KD_FONT_OP_GET)
1145 op->data = compat_ptr(((struct compat_console_font_op *)op)->data);
1146 i = con_font_op(vc, op);
1149 ((struct compat_console_font_op *)op)->data = (unsigned long)op->data;
1150 if (copy_to_user(fontop, op, sizeof(struct compat_console_font_op)))
1155 struct compat_unimapdesc {
1156 unsigned short entry_ct;
1157 compat_caddr_t entries;
1161 compat_unimap_ioctl(unsigned int cmd, struct compat_unimapdesc __user *user_ud,
1162 int perm, struct vc_data *vc)
1164 struct compat_unimapdesc tmp;
1165 struct unipair __user *tmp_entries;
1167 if (copy_from_user(&tmp, user_ud, sizeof tmp))
1169 tmp_entries = compat_ptr(tmp.entries);
1174 return con_set_unimap(vc, tmp.entry_ct, tmp_entries);
1176 if (!perm && fg_console != vc->vc_num)
1178 return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp_entries);
1183 long vt_compat_ioctl(struct tty_struct *tty,
1184 unsigned int cmd, unsigned long arg)
1186 struct vc_data *vc = tty->driver_data;
1187 struct console_font_op op; /* used in multiple places here */
1188 unsigned int console;
1189 void __user *up = (void __user *)arg;
1193 console = vc->vc_num;
1195 if (!vc_cons_allocated(console)) { /* impossible? */
1201 * To have permissions to do most of the vt ioctls, we either have
1202 * to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
1205 if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
1210 * these need special handlers for incompatible data structures
1214 ret = compat_fontx_ioctl(cmd, up, perm, &op);
1218 ret = compat_kdfontop_ioctl(up, perm, &op, vc);
1223 ret = compat_unimap_ioctl(cmd, up, perm, vc);
1227 * all these treat 'arg' as an integer
1246 case VT_DISALLOCATE:
1252 * the rest has a compatible data structure behind arg,
1253 * but we have to convert it to a proper 64 bit pointer.
1256 arg = (unsigned long)compat_ptr(arg);
1263 return vt_ioctl(tty, cmd, arg);
1267 #endif /* CONFIG_COMPAT */
1271 * Performs the back end of a vt switch. Called under the console
1274 static void complete_change_console(struct vc_data *vc)
1276 unsigned char old_vc_mode;
1277 int old = fg_console;
1279 last_console = fg_console;
1282 * If we're switching, we could be going from KD_GRAPHICS to
1283 * KD_TEXT mode or vice versa, which means we need to blank or
1284 * unblank the screen later.
1286 old_vc_mode = vc_cons[fg_console].d->vc_mode;
1290 * This can't appear below a successful kill_pid(). If it did,
1291 * then the *blank_screen operation could occur while X, having
1292 * received acqsig, is waking up on another processor. This
1293 * condition can lead to overlapping accesses to the VGA range
1294 * and the framebuffer (causing system lockups).
1296 * To account for this we duplicate this code below only if the
1297 * controlling process is gone and we've called reset_vc.
1299 if (old_vc_mode != vc->vc_mode) {
1300 if (vc->vc_mode == KD_TEXT)
1301 do_unblank_screen(1);
1307 * If this new console is under process control, send it a signal
1308 * telling it that it has acquired. Also check if it has died and
1309 * clean up (similar to logic employed in change_console())
1311 if (vc->vt_mode.mode == VT_PROCESS) {
1313 * Send the signal as privileged - kill_pid() will
1314 * tell us if the process has gone or something else
1317 if (kill_pid(vc->vt_pid, vc->vt_mode.acqsig, 1) != 0) {
1319 * The controlling process has died, so we revert back to
1320 * normal operation. In this case, we'll also change back
1321 * to KD_TEXT mode. I'm not sure if this is strictly correct
1322 * but it saves the agony when the X server dies and the screen
1323 * remains blanked due to KD_GRAPHICS! It would be nice to do
1324 * this outside of VT_PROCESS but there is no single process
1325 * to account for and tracking tty count may be undesirable.
1329 if (old_vc_mode != vc->vc_mode) {
1330 if (vc->vc_mode == KD_TEXT)
1331 do_unblank_screen(1);
1339 * Wake anyone waiting for their VT to activate
1341 vt_event_post(VT_EVENT_SWITCH, old, vc->vc_num);
1346 * Performs the front-end of a vt switch
1348 void change_console(struct vc_data *new_vc)
1352 if (!new_vc || new_vc->vc_num == fg_console || vt_dont_switch)
1356 * If this vt is in process mode, then we need to handshake with
1357 * that process before switching. Essentially, we store where that
1358 * vt wants to switch to and wait for it to tell us when it's done
1359 * (via VT_RELDISP ioctl).
1361 * We also check to see if the controlling process still exists.
1362 * If it doesn't, we reset this vt to auto mode and continue.
1363 * This is a cheap way to track process control. The worst thing
1364 * that can happen is: we send a signal to a process, it dies, and
1365 * the switch gets "lost" waiting for a response; hopefully, the
1366 * user will try again, we'll detect the process is gone (unless
1367 * the user waits just the right amount of time :-) and revert the
1368 * vt to auto control.
1370 vc = vc_cons[fg_console].d;
1371 if (vc->vt_mode.mode == VT_PROCESS) {
1373 * Send the signal as privileged - kill_pid() will
1374 * tell us if the process has gone or something else
1377 * We need to set vt_newvt *before* sending the signal or we
1380 vc->vt_newvt = new_vc->vc_num;
1381 if (kill_pid(vc->vt_pid, vc->vt_mode.relsig, 1) == 0) {
1383 * It worked. Mark the vt to switch to and
1384 * return. The process needs to send us a
1385 * VT_RELDISP ioctl to complete the switch.
1391 * The controlling process has died, so we revert back to
1392 * normal operation. In this case, we'll also change back
1393 * to KD_TEXT mode. I'm not sure if this is strictly correct
1394 * but it saves the agony when the X server dies and the screen
1395 * remains blanked due to KD_GRAPHICS! It would be nice to do
1396 * this outside of VT_PROCESS but there is no single process
1397 * to account for and tracking tty count may be undesirable.
1402 * Fall through to normal (VT_AUTO) handling of the switch...
1407 * Ignore all switches in KD_GRAPHICS+VT_AUTO mode
1409 if (vc->vc_mode == KD_GRAPHICS)
1412 complete_change_console(new_vc);
1415 /* Perform a kernel triggered VT switch for suspend/resume */
1417 static int disable_vt_switch;
1419 int vt_move_to_console(unsigned int vt, int alloc)
1424 /* Graphics mode - up to X */
1425 if (disable_vt_switch) {
1431 if (alloc && vc_allocate(vt)) {
1432 /* we can't have a free VC for now. Too bad,
1433 * we don't want to mess the screen for now. */
1438 if (set_console(vt)) {
1440 * We're unable to switch to the SUSPEND_CONSOLE.
1441 * Let the calling function know so it can decide
1448 if (vt_waitactive(vt + 1)) {
1449 pr_debug("Suspend: Can't switch VCs.");
1456 * Normally during a suspend, we allocate a new console and switch to it.
1457 * When we resume, we switch back to the original console. This switch
1458 * can be slow, so on systems where the framebuffer can handle restoration
1459 * of video registers anyways, there's little point in doing the console
1460 * switch. This function allows you to disable it by passing it '0'.
1462 void pm_set_vt_switch(int do_switch)
1465 disable_vt_switch = !do_switch;
1468 EXPORT_SYMBOL(pm_set_vt_switch);