mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-24 09:50:04 +00:00
![Ross Lagerwall](/assets/img/avatar_default.png)
Commit 421b40a628
("tty/vt: Fix vc_deallocate() lock order") changed
the behavior when deallocating VT 1. Previously if trying to
deallocate VT1 and it is busy, we would return EBUSY. The commit
changed this to return 0 (success).
This commit restores the old behavior.
Signed-off-by: Ross Lagerwall <rosslagerwall@gmail.com>
Tested-by: Mikael Pettersson <mikpe@it.uu.se>
Acked-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1481 lines
33 KiB
C
1481 lines
33 KiB
C
/*
|
|
* Copyright (C) 1992 obz under the linux copyright
|
|
*
|
|
* Dynamic diacritical handling - aeb@cwi.nl - Dec 1993
|
|
* Dynamic keymap and string allocation - aeb@cwi.nl - May 1994
|
|
* Restrict VT switching via ioctl() - grif@cs.ucr.edu - Dec 1995
|
|
* Some code moved for less code duplication - Andi Kleen - Mar 1997
|
|
* Check put/get_user, cleanups - acme@conectiva.com.br - Jun 2001
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/sched.h>
|
|
#include <linux/tty.h>
|
|
#include <linux/timer.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/compat.h>
|
|
#include <linux/module.h>
|
|
#include <linux/kd.h>
|
|
#include <linux/vt.h>
|
|
#include <linux/string.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/major.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/console.h>
|
|
#include <linux/consolemap.h>
|
|
#include <linux/signal.h>
|
|
#include <linux/suspend.h>
|
|
#include <linux/timex.h>
|
|
|
|
#include <asm/io.h>
|
|
#include <asm/uaccess.h>
|
|
|
|
#include <linux/kbd_kern.h>
|
|
#include <linux/vt_kern.h>
|
|
#include <linux/kbd_diacr.h>
|
|
#include <linux/selection.h>
|
|
|
|
char vt_dont_switch;
|
|
extern struct tty_driver *console_driver;
|
|
|
|
#define VT_IS_IN_USE(i) (console_driver->ttys[i] && console_driver->ttys[i]->count)
|
|
#define VT_BUSY(i) (VT_IS_IN_USE(i) || i == fg_console || vc_cons[i].d == sel_cons)
|
|
|
|
/*
|
|
* Console (vt and kd) routines, as defined by USL SVR4 manual, and by
|
|
* experimentation and study of X386 SYSV handling.
|
|
*
|
|
* One point of difference: SYSV vt's are /dev/vtX, which X >= 0, and
|
|
* /dev/console is a separate ttyp. Under Linux, /dev/tty0 is /dev/console,
|
|
* and the vc start at /dev/ttyX, X >= 1. We maintain that here, so we will
|
|
* always treat our set of vt as numbered 1..MAX_NR_CONSOLES (corresponding to
|
|
* ttys 0..MAX_NR_CONSOLES-1). Explicitly naming VT 0 is illegal, but using
|
|
* /dev/tty0 (fg_console) as a target is legal, since an implicit aliasing
|
|
* to the current console is done by the main ioctl code.
|
|
*/
|
|
|
|
#ifdef CONFIG_X86
|
|
#include <linux/syscalls.h>
|
|
#endif
|
|
|
|
static void complete_change_console(struct vc_data *vc);
|
|
|
|
/*
|
|
* User space VT_EVENT handlers
|
|
*/
|
|
|
|
struct vt_event_wait {
|
|
struct list_head list;
|
|
struct vt_event event;
|
|
int done;
|
|
};
|
|
|
|
static LIST_HEAD(vt_events);
|
|
static DEFINE_SPINLOCK(vt_event_lock);
|
|
static DECLARE_WAIT_QUEUE_HEAD(vt_event_waitqueue);
|
|
|
|
/**
|
|
* vt_event_post
|
|
* @event: the event that occurred
|
|
* @old: old console
|
|
* @new: new console
|
|
*
|
|
* Post an VT event to interested VT handlers
|
|
*/
|
|
|
|
void vt_event_post(unsigned int event, unsigned int old, unsigned int new)
|
|
{
|
|
struct list_head *pos, *head;
|
|
unsigned long flags;
|
|
int wake = 0;
|
|
|
|
spin_lock_irqsave(&vt_event_lock, flags);
|
|
head = &vt_events;
|
|
|
|
list_for_each(pos, head) {
|
|
struct vt_event_wait *ve = list_entry(pos,
|
|
struct vt_event_wait, list);
|
|
if (!(ve->event.event & event))
|
|
continue;
|
|
ve->event.event = event;
|
|
/* kernel view is consoles 0..n-1, user space view is
|
|
console 1..n with 0 meaning current, so we must bias */
|
|
ve->event.oldev = old + 1;
|
|
ve->event.newev = new + 1;
|
|
wake = 1;
|
|
ve->done = 1;
|
|
}
|
|
spin_unlock_irqrestore(&vt_event_lock, flags);
|
|
if (wake)
|
|
wake_up_interruptible(&vt_event_waitqueue);
|
|
}
|
|
|
|
static void __vt_event_queue(struct vt_event_wait *vw)
|
|
{
|
|
unsigned long flags;
|
|
/* Prepare the event */
|
|
INIT_LIST_HEAD(&vw->list);
|
|
vw->done = 0;
|
|
/* Queue our event */
|
|
spin_lock_irqsave(&vt_event_lock, flags);
|
|
list_add(&vw->list, &vt_events);
|
|
spin_unlock_irqrestore(&vt_event_lock, flags);
|
|
}
|
|
|
|
static void __vt_event_wait(struct vt_event_wait *vw)
|
|
{
|
|
/* Wait for it to pass */
|
|
wait_event_interruptible(vt_event_waitqueue, vw->done);
|
|
}
|
|
|
|
static void __vt_event_dequeue(struct vt_event_wait *vw)
|
|
{
|
|
unsigned long flags;
|
|
|
|
/* Dequeue it */
|
|
spin_lock_irqsave(&vt_event_lock, flags);
|
|
list_del(&vw->list);
|
|
spin_unlock_irqrestore(&vt_event_lock, flags);
|
|
}
|
|
|
|
/**
|
|
* vt_event_wait - wait for an event
|
|
* @vw: our event
|
|
*
|
|
* Waits for an event to occur which completes our vt_event_wait
|
|
* structure. On return the structure has wv->done set to 1 for success
|
|
* or 0 if some event such as a signal ended the wait.
|
|
*/
|
|
|
|
static void vt_event_wait(struct vt_event_wait *vw)
|
|
{
|
|
__vt_event_queue(vw);
|
|
__vt_event_wait(vw);
|
|
__vt_event_dequeue(vw);
|
|
}
|
|
|
|
/**
|
|
* vt_event_wait_ioctl - event ioctl handler
|
|
* @arg: argument to ioctl
|
|
*
|
|
* Implement the VT_WAITEVENT ioctl using the VT event interface
|
|
*/
|
|
|
|
static int vt_event_wait_ioctl(struct vt_event __user *event)
|
|
{
|
|
struct vt_event_wait vw;
|
|
|
|
if (copy_from_user(&vw.event, event, sizeof(struct vt_event)))
|
|
return -EFAULT;
|
|
/* Highest supported event for now */
|
|
if (vw.event.event & ~VT_MAX_EVENT)
|
|
return -EINVAL;
|
|
|
|
vt_event_wait(&vw);
|
|
/* If it occurred report it */
|
|
if (vw.done) {
|
|
if (copy_to_user(event, &vw.event, sizeof(struct vt_event)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
return -EINTR;
|
|
}
|
|
|
|
/**
|
|
* vt_waitactive - active console wait
|
|
* @event: event code
|
|
* @n: new console
|
|
*
|
|
* Helper for event waits. Used to implement the legacy
|
|
* event waiting ioctls in terms of events
|
|
*/
|
|
|
|
int vt_waitactive(int n)
|
|
{
|
|
struct vt_event_wait vw;
|
|
do {
|
|
vw.event.event = VT_EVENT_SWITCH;
|
|
__vt_event_queue(&vw);
|
|
if (n == fg_console + 1) {
|
|
__vt_event_dequeue(&vw);
|
|
break;
|
|
}
|
|
__vt_event_wait(&vw);
|
|
__vt_event_dequeue(&vw);
|
|
if (vw.done == 0)
|
|
return -EINTR;
|
|
} while (vw.event.newev != n);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* these are the valid i/o ports we're allowed to change. they map all the
|
|
* video ports
|
|
*/
|
|
#define GPFIRST 0x3b4
|
|
#define GPLAST 0x3df
|
|
#define GPNUM (GPLAST - GPFIRST + 1)
|
|
|
|
|
|
|
|
static inline int
|
|
do_fontx_ioctl(int cmd, struct consolefontdesc __user *user_cfd, int perm, struct console_font_op *op)
|
|
{
|
|
struct consolefontdesc cfdarg;
|
|
int i;
|
|
|
|
if (copy_from_user(&cfdarg, user_cfd, sizeof(struct consolefontdesc)))
|
|
return -EFAULT;
|
|
|
|
switch (cmd) {
|
|
case PIO_FONTX:
|
|
if (!perm)
|
|
return -EPERM;
|
|
op->op = KD_FONT_OP_SET;
|
|
op->flags = KD_FONT_FLAG_OLD;
|
|
op->width = 8;
|
|
op->height = cfdarg.charheight;
|
|
op->charcount = cfdarg.charcount;
|
|
op->data = cfdarg.chardata;
|
|
return con_font_op(vc_cons[fg_console].d, op);
|
|
case GIO_FONTX: {
|
|
op->op = KD_FONT_OP_GET;
|
|
op->flags = KD_FONT_FLAG_OLD;
|
|
op->width = 8;
|
|
op->height = cfdarg.charheight;
|
|
op->charcount = cfdarg.charcount;
|
|
op->data = cfdarg.chardata;
|
|
i = con_font_op(vc_cons[fg_console].d, op);
|
|
if (i)
|
|
return i;
|
|
cfdarg.charheight = op->height;
|
|
cfdarg.charcount = op->charcount;
|
|
if (copy_to_user(user_cfd, &cfdarg, sizeof(struct consolefontdesc)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
}
|
|
return -EINVAL;
|
|
}
|
|
|
|
static inline int
|
|
do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud, int perm, struct vc_data *vc)
|
|
{
|
|
struct unimapdesc tmp;
|
|
|
|
if (copy_from_user(&tmp, user_ud, sizeof tmp))
|
|
return -EFAULT;
|
|
if (tmp.entries)
|
|
if (!access_ok(VERIFY_WRITE, tmp.entries,
|
|
tmp.entry_ct*sizeof(struct unipair)))
|
|
return -EFAULT;
|
|
switch (cmd) {
|
|
case PIO_UNIMAP:
|
|
if (!perm)
|
|
return -EPERM;
|
|
return con_set_unimap(vc, tmp.entry_ct, tmp.entries);
|
|
case GIO_UNIMAP:
|
|
if (!perm && fg_console != vc->vc_num)
|
|
return -EPERM;
|
|
return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp.entries);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* deallocate a single console, if possible (leave 0) */
|
|
static int vt_disallocate(unsigned int vc_num)
|
|
{
|
|
struct vc_data *vc = NULL;
|
|
int ret = 0;
|
|
|
|
console_lock();
|
|
if (VT_BUSY(vc_num))
|
|
ret = -EBUSY;
|
|
else if (vc_num)
|
|
vc = vc_deallocate(vc_num);
|
|
console_unlock();
|
|
|
|
if (vc && vc_num >= MIN_NR_CONSOLES) {
|
|
tty_port_destroy(&vc->port);
|
|
kfree(vc);
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* deallocate all unused consoles, but leave 0 */
|
|
static void vt_disallocate_all(void)
|
|
{
|
|
struct vc_data *vc[MAX_NR_CONSOLES];
|
|
int i;
|
|
|
|
console_lock();
|
|
for (i = 1; i < MAX_NR_CONSOLES; i++)
|
|
if (!VT_BUSY(i))
|
|
vc[i] = vc_deallocate(i);
|
|
else
|
|
vc[i] = NULL;
|
|
console_unlock();
|
|
|
|
for (i = 1; i < MAX_NR_CONSOLES; i++) {
|
|
if (vc[i] && i >= MIN_NR_CONSOLES) {
|
|
tty_port_destroy(&vc[i]->port);
|
|
kfree(vc[i]);
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
/*
|
|
* We handle the console-specific ioctl's here. We allow the
|
|
* capability to modify any console, not just the fg_console.
|
|
*/
|
|
int vt_ioctl(struct tty_struct *tty,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct vc_data *vc = tty->driver_data;
|
|
struct console_font_op op; /* used in multiple places here */
|
|
unsigned int console;
|
|
unsigned char ucval;
|
|
unsigned int uival;
|
|
void __user *up = (void __user *)arg;
|
|
int i, perm;
|
|
int ret = 0;
|
|
|
|
console = vc->vc_num;
|
|
|
|
|
|
if (!vc_cons_allocated(console)) { /* impossible? */
|
|
ret = -ENOIOCTLCMD;
|
|
goto out;
|
|
}
|
|
|
|
|
|
/*
|
|
* To have permissions to do most of the vt ioctls, we either have
|
|
* to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
|
|
*/
|
|
perm = 0;
|
|
if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
|
|
perm = 1;
|
|
|
|
switch (cmd) {
|
|
case TIOCLINUX:
|
|
ret = tioclinux(tty, arg);
|
|
break;
|
|
case KIOCSOUND:
|
|
if (!perm)
|
|
return -EPERM;
|
|
/*
|
|
* The use of PIT_TICK_RATE is historic, it used to be
|
|
* the platform-dependent CLOCK_TICK_RATE between 2.6.12
|
|
* and 2.6.36, which was a minor but unfortunate ABI
|
|
* change. kd_mksound is locked by the input layer.
|
|
*/
|
|
if (arg)
|
|
arg = PIT_TICK_RATE / arg;
|
|
kd_mksound(arg, 0);
|
|
break;
|
|
|
|
case KDMKTONE:
|
|
if (!perm)
|
|
return -EPERM;
|
|
{
|
|
unsigned int ticks, count;
|
|
|
|
/*
|
|
* Generate the tone for the appropriate number of ticks.
|
|
* If the time is zero, turn off sound ourselves.
|
|
*/
|
|
ticks = HZ * ((arg >> 16) & 0xffff) / 1000;
|
|
count = ticks ? (arg & 0xffff) : 0;
|
|
if (count)
|
|
count = PIT_TICK_RATE / count;
|
|
kd_mksound(count, ticks);
|
|
break;
|
|
}
|
|
|
|
case KDGKBTYPE:
|
|
/*
|
|
* this is naïve.
|
|
*/
|
|
ucval = KB_101;
|
|
ret = put_user(ucval, (char __user *)arg);
|
|
break;
|
|
|
|
/*
|
|
* These cannot be implemented on any machine that implements
|
|
* ioperm() in user level (such as Alpha PCs) or not at all.
|
|
*
|
|
* XXX: you should never use these, just call ioperm directly..
|
|
*/
|
|
#ifdef CONFIG_X86
|
|
case KDADDIO:
|
|
case KDDELIO:
|
|
/*
|
|
* KDADDIO and KDDELIO may be able to add ports beyond what
|
|
* we reject here, but to be safe...
|
|
*
|
|
* These are locked internally via sys_ioperm
|
|
*/
|
|
if (arg < GPFIRST || arg > GPLAST) {
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
ret = sys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
|
|
break;
|
|
|
|
case KDENABIO:
|
|
case KDDISABIO:
|
|
ret = sys_ioperm(GPFIRST, GPNUM,
|
|
(cmd == KDENABIO)) ? -ENXIO : 0;
|
|
break;
|
|
#endif
|
|
|
|
/* Linux m68k/i386 interface for setting the keyboard delay/repeat rate */
|
|
|
|
case KDKBDREP:
|
|
{
|
|
struct kbd_repeat kbrep;
|
|
|
|
if (!capable(CAP_SYS_TTY_CONFIG))
|
|
return -EPERM;
|
|
|
|
if (copy_from_user(&kbrep, up, sizeof(struct kbd_repeat))) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
ret = kbd_rate(&kbrep);
|
|
if (ret)
|
|
break;
|
|
if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat)))
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
|
|
case KDSETMODE:
|
|
/*
|
|
* currently, setting the mode from KD_TEXT to KD_GRAPHICS
|
|
* doesn't do a whole lot. i'm not sure if it should do any
|
|
* restoration of modes or what...
|
|
*
|
|
* XXX It should at least call into the driver, fbdev's definitely
|
|
* need to restore their engine state. --BenH
|
|
*/
|
|
if (!perm)
|
|
return -EPERM;
|
|
switch (arg) {
|
|
case KD_GRAPHICS:
|
|
break;
|
|
case KD_TEXT0:
|
|
case KD_TEXT1:
|
|
arg = KD_TEXT;
|
|
case KD_TEXT:
|
|
break;
|
|
default:
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
/* FIXME: this needs the console lock extending */
|
|
if (vc->vc_mode == (unsigned char) arg)
|
|
break;
|
|
vc->vc_mode = (unsigned char) arg;
|
|
if (console != fg_console)
|
|
break;
|
|
/*
|
|
* explicitly blank/unblank the screen if switching modes
|
|
*/
|
|
console_lock();
|
|
if (arg == KD_TEXT)
|
|
do_unblank_screen(1);
|
|
else
|
|
do_blank_screen(1);
|
|
console_unlock();
|
|
break;
|
|
|
|
case KDGETMODE:
|
|
uival = vc->vc_mode;
|
|
goto setint;
|
|
|
|
case KDMAPDISP:
|
|
case KDUNMAPDISP:
|
|
/*
|
|
* these work like a combination of mmap and KDENABIO.
|
|
* this could be easily finished.
|
|
*/
|
|
ret = -EINVAL;
|
|
break;
|
|
|
|
case KDSKBMODE:
|
|
if (!perm)
|
|
return -EPERM;
|
|
ret = vt_do_kdskbmode(console, arg);
|
|
if (ret == 0)
|
|
tty_ldisc_flush(tty);
|
|
break;
|
|
|
|
case KDGKBMODE:
|
|
uival = vt_do_kdgkbmode(console);
|
|
ret = put_user(uival, (int __user *)arg);
|
|
break;
|
|
|
|
/* this could be folded into KDSKBMODE, but for compatibility
|
|
reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
|
|
case KDSKBMETA:
|
|
ret = vt_do_kdskbmeta(console, arg);
|
|
break;
|
|
|
|
case KDGKBMETA:
|
|
/* FIXME: should review whether this is worth locking */
|
|
uival = vt_do_kdgkbmeta(console);
|
|
setint:
|
|
ret = put_user(uival, (int __user *)arg);
|
|
break;
|
|
|
|
case KDGETKEYCODE:
|
|
case KDSETKEYCODE:
|
|
if(!capable(CAP_SYS_TTY_CONFIG))
|
|
perm = 0;
|
|
ret = vt_do_kbkeycode_ioctl(cmd, up, perm);
|
|
break;
|
|
|
|
case KDGKBENT:
|
|
case KDSKBENT:
|
|
ret = vt_do_kdsk_ioctl(cmd, up, perm, console);
|
|
break;
|
|
|
|
case KDGKBSENT:
|
|
case KDSKBSENT:
|
|
ret = vt_do_kdgkb_ioctl(cmd, up, perm);
|
|
break;
|
|
|
|
/* Diacritical processing. Handled in keyboard.c as it has
|
|
to operate on the keyboard locks and structures */
|
|
case KDGKBDIACR:
|
|
case KDGKBDIACRUC:
|
|
case KDSKBDIACR:
|
|
case KDSKBDIACRUC:
|
|
ret = vt_do_diacrit(cmd, up, perm);
|
|
break;
|
|
|
|
/* the ioctls below read/set the flags usually shown in the leds */
|
|
/* don't use them - they will go away without warning */
|
|
case KDGKBLED:
|
|
case KDSKBLED:
|
|
case KDGETLED:
|
|
case KDSETLED:
|
|
ret = vt_do_kdskled(console, cmd, arg, perm);
|
|
break;
|
|
|
|
/*
|
|
* A process can indicate its willingness to accept signals
|
|
* generated by pressing an appropriate key combination.
|
|
* Thus, one can have a daemon that e.g. spawns a new console
|
|
* upon a keypress and then changes to it.
|
|
* See also the kbrequest field of inittab(5).
|
|
*/
|
|
case KDSIGACCEPT:
|
|
{
|
|
if (!perm || !capable(CAP_KILL))
|
|
return -EPERM;
|
|
if (!valid_signal(arg) || arg < 1 || arg == SIGKILL)
|
|
ret = -EINVAL;
|
|
else {
|
|
spin_lock_irq(&vt_spawn_con.lock);
|
|
put_pid(vt_spawn_con.pid);
|
|
vt_spawn_con.pid = get_pid(task_pid(current));
|
|
vt_spawn_con.sig = arg;
|
|
spin_unlock_irq(&vt_spawn_con.lock);
|
|
}
|
|
break;
|
|
}
|
|
|
|
case VT_SETMODE:
|
|
{
|
|
struct vt_mode tmp;
|
|
|
|
if (!perm)
|
|
return -EPERM;
|
|
if (copy_from_user(&tmp, up, sizeof(struct vt_mode))) {
|
|
ret = -EFAULT;
|
|
goto out;
|
|
}
|
|
if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS) {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
console_lock();
|
|
vc->vt_mode = tmp;
|
|
/* the frsig is ignored, so we set it to 0 */
|
|
vc->vt_mode.frsig = 0;
|
|
put_pid(vc->vt_pid);
|
|
vc->vt_pid = get_pid(task_pid(current));
|
|
/* no switch is required -- saw@shade.msu.ru */
|
|
vc->vt_newvt = -1;
|
|
console_unlock();
|
|
break;
|
|
}
|
|
|
|
case VT_GETMODE:
|
|
{
|
|
struct vt_mode tmp;
|
|
int rc;
|
|
|
|
console_lock();
|
|
memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
|
|
console_unlock();
|
|
|
|
rc = copy_to_user(up, &tmp, sizeof(struct vt_mode));
|
|
if (rc)
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Returns global vt state. Note that VT 0 is always open, since
|
|
* it's an alias for the current VT, and people can't use it here.
|
|
* We cannot return state for more than 16 VTs, since v_state is short.
|
|
*/
|
|
case VT_GETSTATE:
|
|
{
|
|
struct vt_stat __user *vtstat = up;
|
|
unsigned short state, mask;
|
|
|
|
/* Review: FIXME: Console lock ? */
|
|
if (put_user(fg_console + 1, &vtstat->v_active))
|
|
ret = -EFAULT;
|
|
else {
|
|
state = 1; /* /dev/tty0 is always open */
|
|
for (i = 0, mask = 2; i < MAX_NR_CONSOLES && mask;
|
|
++i, mask <<= 1)
|
|
if (VT_IS_IN_USE(i))
|
|
state |= mask;
|
|
ret = put_user(state, &vtstat->v_state);
|
|
}
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Returns the first available (non-opened) console.
|
|
*/
|
|
case VT_OPENQRY:
|
|
/* FIXME: locking ? - but then this is a stupid API */
|
|
for (i = 0; i < MAX_NR_CONSOLES; ++i)
|
|
if (! VT_IS_IN_USE(i))
|
|
break;
|
|
uival = i < MAX_NR_CONSOLES ? (i+1) : -1;
|
|
goto setint;
|
|
|
|
/*
|
|
* ioctl(fd, VT_ACTIVATE, num) will cause us to switch to vt # num,
|
|
* with num >= 1 (switches to vt 0, our console, are not allowed, just
|
|
* to preserve sanity).
|
|
*/
|
|
case VT_ACTIVATE:
|
|
if (!perm)
|
|
return -EPERM;
|
|
if (arg == 0 || arg > MAX_NR_CONSOLES)
|
|
ret = -ENXIO;
|
|
else {
|
|
arg--;
|
|
console_lock();
|
|
ret = vc_allocate(arg);
|
|
console_unlock();
|
|
if (ret)
|
|
break;
|
|
set_console(arg);
|
|
}
|
|
break;
|
|
|
|
case VT_SETACTIVATE:
|
|
{
|
|
struct vt_setactivate vsa;
|
|
|
|
if (!perm)
|
|
return -EPERM;
|
|
|
|
if (copy_from_user(&vsa, (struct vt_setactivate __user *)arg,
|
|
sizeof(struct vt_setactivate))) {
|
|
ret = -EFAULT;
|
|
goto out;
|
|
}
|
|
if (vsa.console == 0 || vsa.console > MAX_NR_CONSOLES)
|
|
ret = -ENXIO;
|
|
else {
|
|
vsa.console--;
|
|
console_lock();
|
|
ret = vc_allocate(vsa.console);
|
|
if (ret == 0) {
|
|
struct vc_data *nvc;
|
|
/* This is safe providing we don't drop the
|
|
console sem between vc_allocate and
|
|
finishing referencing nvc */
|
|
nvc = vc_cons[vsa.console].d;
|
|
nvc->vt_mode = vsa.mode;
|
|
nvc->vt_mode.frsig = 0;
|
|
put_pid(nvc->vt_pid);
|
|
nvc->vt_pid = get_pid(task_pid(current));
|
|
}
|
|
console_unlock();
|
|
if (ret)
|
|
break;
|
|
/* Commence switch and lock */
|
|
/* Review set_console locks */
|
|
set_console(vsa.console);
|
|
}
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* wait until the specified VT has been activated
|
|
*/
|
|
case VT_WAITACTIVE:
|
|
if (!perm)
|
|
return -EPERM;
|
|
if (arg == 0 || arg > MAX_NR_CONSOLES)
|
|
ret = -ENXIO;
|
|
else
|
|
ret = vt_waitactive(arg);
|
|
break;
|
|
|
|
/*
|
|
* If a vt is under process control, the kernel will not switch to it
|
|
* immediately, but postpone the operation until the process calls this
|
|
* ioctl, allowing the switch to complete.
|
|
*
|
|
* According to the X sources this is the behavior:
|
|
* 0: pending switch-from not OK
|
|
* 1: pending switch-from OK
|
|
* 2: completed switch-to OK
|
|
*/
|
|
case VT_RELDISP:
|
|
if (!perm)
|
|
return -EPERM;
|
|
|
|
console_lock();
|
|
if (vc->vt_mode.mode != VT_PROCESS) {
|
|
console_unlock();
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
/*
|
|
* Switching-from response
|
|
*/
|
|
if (vc->vt_newvt >= 0) {
|
|
if (arg == 0)
|
|
/*
|
|
* Switch disallowed, so forget we were trying
|
|
* to do it.
|
|
*/
|
|
vc->vt_newvt = -1;
|
|
|
|
else {
|
|
/*
|
|
* The current vt has been released, so
|
|
* complete the switch.
|
|
*/
|
|
int newvt;
|
|
newvt = vc->vt_newvt;
|
|
vc->vt_newvt = -1;
|
|
ret = vc_allocate(newvt);
|
|
if (ret) {
|
|
console_unlock();
|
|
break;
|
|
}
|
|
/*
|
|
* When we actually do the console switch,
|
|
* make sure we are atomic with respect to
|
|
* other console switches..
|
|
*/
|
|
complete_change_console(vc_cons[newvt].d);
|
|
}
|
|
} else {
|
|
/*
|
|
* Switched-to response
|
|
*/
|
|
/*
|
|
* If it's just an ACK, ignore it
|
|
*/
|
|
if (arg != VT_ACKACQ)
|
|
ret = -EINVAL;
|
|
}
|
|
console_unlock();
|
|
break;
|
|
|
|
/*
|
|
* Disallocate memory associated to VT (but leave VT1)
|
|
*/
|
|
case VT_DISALLOCATE:
|
|
if (arg > MAX_NR_CONSOLES) {
|
|
ret = -ENXIO;
|
|
break;
|
|
}
|
|
if (arg == 0)
|
|
vt_disallocate_all();
|
|
else
|
|
ret = vt_disallocate(--arg);
|
|
break;
|
|
|
|
case VT_RESIZE:
|
|
{
|
|
struct vt_sizes __user *vtsizes = up;
|
|
struct vc_data *vc;
|
|
|
|
ushort ll,cc;
|
|
if (!perm)
|
|
return -EPERM;
|
|
if (get_user(ll, &vtsizes->v_rows) ||
|
|
get_user(cc, &vtsizes->v_cols))
|
|
ret = -EFAULT;
|
|
else {
|
|
console_lock();
|
|
for (i = 0; i < MAX_NR_CONSOLES; i++) {
|
|
vc = vc_cons[i].d;
|
|
|
|
if (vc) {
|
|
vc->vc_resize_user = 1;
|
|
/* FIXME: review v tty lock */
|
|
vc_resize(vc_cons[i].d, cc, ll);
|
|
}
|
|
}
|
|
console_unlock();
|
|
}
|
|
break;
|
|
}
|
|
|
|
case VT_RESIZEX:
|
|
{
|
|
struct vt_consize __user *vtconsize = up;
|
|
ushort ll,cc,vlin,clin,vcol,ccol;
|
|
if (!perm)
|
|
return -EPERM;
|
|
if (!access_ok(VERIFY_READ, vtconsize,
|
|
sizeof(struct vt_consize))) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
/* FIXME: Should check the copies properly */
|
|
__get_user(ll, &vtconsize->v_rows);
|
|
__get_user(cc, &vtconsize->v_cols);
|
|
__get_user(vlin, &vtconsize->v_vlin);
|
|
__get_user(clin, &vtconsize->v_clin);
|
|
__get_user(vcol, &vtconsize->v_vcol);
|
|
__get_user(ccol, &vtconsize->v_ccol);
|
|
vlin = vlin ? vlin : vc->vc_scan_lines;
|
|
if (clin) {
|
|
if (ll) {
|
|
if (ll != vlin/clin) {
|
|
/* Parameters don't add up */
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
} else
|
|
ll = vlin/clin;
|
|
}
|
|
if (vcol && ccol) {
|
|
if (cc) {
|
|
if (cc != vcol/ccol) {
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
} else
|
|
cc = vcol/ccol;
|
|
}
|
|
|
|
if (clin > 32) {
|
|
ret = -EINVAL;
|
|
break;
|
|
}
|
|
|
|
for (i = 0; i < MAX_NR_CONSOLES; i++) {
|
|
if (!vc_cons[i].d)
|
|
continue;
|
|
console_lock();
|
|
if (vlin)
|
|
vc_cons[i].d->vc_scan_lines = vlin;
|
|
if (clin)
|
|
vc_cons[i].d->vc_font.height = clin;
|
|
vc_cons[i].d->vc_resize_user = 1;
|
|
vc_resize(vc_cons[i].d, cc, ll);
|
|
console_unlock();
|
|
}
|
|
break;
|
|
}
|
|
|
|
case PIO_FONT: {
|
|
if (!perm)
|
|
return -EPERM;
|
|
op.op = KD_FONT_OP_SET;
|
|
op.flags = KD_FONT_FLAG_OLD | KD_FONT_FLAG_DONT_RECALC; /* Compatibility */
|
|
op.width = 8;
|
|
op.height = 0;
|
|
op.charcount = 256;
|
|
op.data = up;
|
|
ret = con_font_op(vc_cons[fg_console].d, &op);
|
|
break;
|
|
}
|
|
|
|
case GIO_FONT: {
|
|
op.op = KD_FONT_OP_GET;
|
|
op.flags = KD_FONT_FLAG_OLD;
|
|
op.width = 8;
|
|
op.height = 32;
|
|
op.charcount = 256;
|
|
op.data = up;
|
|
ret = con_font_op(vc_cons[fg_console].d, &op);
|
|
break;
|
|
}
|
|
|
|
case PIO_CMAP:
|
|
if (!perm)
|
|
ret = -EPERM;
|
|
else
|
|
ret = con_set_cmap(up);
|
|
break;
|
|
|
|
case GIO_CMAP:
|
|
ret = con_get_cmap(up);
|
|
break;
|
|
|
|
case PIO_FONTX:
|
|
case GIO_FONTX:
|
|
ret = do_fontx_ioctl(cmd, up, perm, &op);
|
|
break;
|
|
|
|
case PIO_FONTRESET:
|
|
{
|
|
if (!perm)
|
|
return -EPERM;
|
|
|
|
#ifdef BROKEN_GRAPHICS_PROGRAMS
|
|
/* With BROKEN_GRAPHICS_PROGRAMS defined, the default
|
|
font is not saved. */
|
|
ret = -ENOSYS;
|
|
break;
|
|
#else
|
|
{
|
|
op.op = KD_FONT_OP_SET_DEFAULT;
|
|
op.data = NULL;
|
|
ret = con_font_op(vc_cons[fg_console].d, &op);
|
|
if (ret)
|
|
break;
|
|
console_lock();
|
|
con_set_default_unimap(vc_cons[fg_console].d);
|
|
console_unlock();
|
|
break;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
case KDFONTOP: {
|
|
if (copy_from_user(&op, up, sizeof(op))) {
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
if (!perm && op.op != KD_FONT_OP_GET)
|
|
return -EPERM;
|
|
ret = con_font_op(vc, &op);
|
|
if (ret)
|
|
break;
|
|
if (copy_to_user(up, &op, sizeof(op)))
|
|
ret = -EFAULT;
|
|
break;
|
|
}
|
|
|
|
case PIO_SCRNMAP:
|
|
if (!perm)
|
|
ret = -EPERM;
|
|
else
|
|
ret = con_set_trans_old(up);
|
|
break;
|
|
|
|
case GIO_SCRNMAP:
|
|
ret = con_get_trans_old(up);
|
|
break;
|
|
|
|
case PIO_UNISCRNMAP:
|
|
if (!perm)
|
|
ret = -EPERM;
|
|
else
|
|
ret = con_set_trans_new(up);
|
|
break;
|
|
|
|
case GIO_UNISCRNMAP:
|
|
ret = con_get_trans_new(up);
|
|
break;
|
|
|
|
case PIO_UNIMAPCLR:
|
|
{ struct unimapinit ui;
|
|
if (!perm)
|
|
return -EPERM;
|
|
ret = copy_from_user(&ui, up, sizeof(struct unimapinit));
|
|
if (ret)
|
|
ret = -EFAULT;
|
|
else
|
|
con_clear_unimap(vc, &ui);
|
|
break;
|
|
}
|
|
|
|
case PIO_UNIMAP:
|
|
case GIO_UNIMAP:
|
|
ret = do_unimap_ioctl(cmd, up, perm, vc);
|
|
break;
|
|
|
|
case VT_LOCKSWITCH:
|
|
if (!capable(CAP_SYS_TTY_CONFIG))
|
|
return -EPERM;
|
|
vt_dont_switch = 1;
|
|
break;
|
|
case VT_UNLOCKSWITCH:
|
|
if (!capable(CAP_SYS_TTY_CONFIG))
|
|
return -EPERM;
|
|
vt_dont_switch = 0;
|
|
break;
|
|
case VT_GETHIFONTMASK:
|
|
ret = put_user(vc->vc_hi_font_mask,
|
|
(unsigned short __user *)arg);
|
|
break;
|
|
case VT_WAITEVENT:
|
|
ret = vt_event_wait_ioctl((struct vt_event __user *)arg);
|
|
break;
|
|
default:
|
|
ret = -ENOIOCTLCMD;
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
void reset_vc(struct vc_data *vc)
|
|
{
|
|
vc->vc_mode = KD_TEXT;
|
|
vt_reset_unicode(vc->vc_num);
|
|
vc->vt_mode.mode = VT_AUTO;
|
|
vc->vt_mode.waitv = 0;
|
|
vc->vt_mode.relsig = 0;
|
|
vc->vt_mode.acqsig = 0;
|
|
vc->vt_mode.frsig = 0;
|
|
put_pid(vc->vt_pid);
|
|
vc->vt_pid = NULL;
|
|
vc->vt_newvt = -1;
|
|
if (!in_interrupt()) /* Via keyboard.c:SAK() - akpm */
|
|
reset_palette(vc);
|
|
}
|
|
|
|
void vc_SAK(struct work_struct *work)
|
|
{
|
|
struct vc *vc_con =
|
|
container_of(work, struct vc, SAK_work);
|
|
struct vc_data *vc;
|
|
struct tty_struct *tty;
|
|
|
|
console_lock();
|
|
vc = vc_con->d;
|
|
if (vc) {
|
|
/* FIXME: review tty ref counting */
|
|
tty = vc->port.tty;
|
|
/*
|
|
* SAK should also work in all raw modes and reset
|
|
* them properly.
|
|
*/
|
|
if (tty)
|
|
__do_SAK(tty);
|
|
reset_vc(vc);
|
|
}
|
|
console_unlock();
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
|
|
struct compat_consolefontdesc {
|
|
unsigned short charcount; /* characters in font (256 or 512) */
|
|
unsigned short charheight; /* scan lines per character (1-32) */
|
|
compat_caddr_t chardata; /* font data in expanded form */
|
|
};
|
|
|
|
static inline int
|
|
compat_fontx_ioctl(int cmd, struct compat_consolefontdesc __user *user_cfd,
|
|
int perm, struct console_font_op *op)
|
|
{
|
|
struct compat_consolefontdesc cfdarg;
|
|
int i;
|
|
|
|
if (copy_from_user(&cfdarg, user_cfd, sizeof(struct compat_consolefontdesc)))
|
|
return -EFAULT;
|
|
|
|
switch (cmd) {
|
|
case PIO_FONTX:
|
|
if (!perm)
|
|
return -EPERM;
|
|
op->op = KD_FONT_OP_SET;
|
|
op->flags = KD_FONT_FLAG_OLD;
|
|
op->width = 8;
|
|
op->height = cfdarg.charheight;
|
|
op->charcount = cfdarg.charcount;
|
|
op->data = compat_ptr(cfdarg.chardata);
|
|
return con_font_op(vc_cons[fg_console].d, op);
|
|
case GIO_FONTX:
|
|
op->op = KD_FONT_OP_GET;
|
|
op->flags = KD_FONT_FLAG_OLD;
|
|
op->width = 8;
|
|
op->height = cfdarg.charheight;
|
|
op->charcount = cfdarg.charcount;
|
|
op->data = compat_ptr(cfdarg.chardata);
|
|
i = con_font_op(vc_cons[fg_console].d, op);
|
|
if (i)
|
|
return i;
|
|
cfdarg.charheight = op->height;
|
|
cfdarg.charcount = op->charcount;
|
|
if (copy_to_user(user_cfd, &cfdarg, sizeof(struct compat_consolefontdesc)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
return -EINVAL;
|
|
}
|
|
|
|
struct compat_console_font_op {
|
|
compat_uint_t op; /* operation code KD_FONT_OP_* */
|
|
compat_uint_t flags; /* KD_FONT_FLAG_* */
|
|
compat_uint_t width, height; /* font size */
|
|
compat_uint_t charcount;
|
|
compat_caddr_t data; /* font data with height fixed to 32 */
|
|
};
|
|
|
|
static inline int
|
|
compat_kdfontop_ioctl(struct compat_console_font_op __user *fontop,
|
|
int perm, struct console_font_op *op, struct vc_data *vc)
|
|
{
|
|
int i;
|
|
|
|
if (copy_from_user(op, fontop, sizeof(struct compat_console_font_op)))
|
|
return -EFAULT;
|
|
if (!perm && op->op != KD_FONT_OP_GET)
|
|
return -EPERM;
|
|
op->data = compat_ptr(((struct compat_console_font_op *)op)->data);
|
|
i = con_font_op(vc, op);
|
|
if (i)
|
|
return i;
|
|
((struct compat_console_font_op *)op)->data = (unsigned long)op->data;
|
|
if (copy_to_user(fontop, op, sizeof(struct compat_console_font_op)))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
struct compat_unimapdesc {
|
|
unsigned short entry_ct;
|
|
compat_caddr_t entries;
|
|
};
|
|
|
|
static inline int
|
|
compat_unimap_ioctl(unsigned int cmd, struct compat_unimapdesc __user *user_ud,
|
|
int perm, struct vc_data *vc)
|
|
{
|
|
struct compat_unimapdesc tmp;
|
|
struct unipair __user *tmp_entries;
|
|
|
|
if (copy_from_user(&tmp, user_ud, sizeof tmp))
|
|
return -EFAULT;
|
|
tmp_entries = compat_ptr(tmp.entries);
|
|
if (tmp_entries)
|
|
if (!access_ok(VERIFY_WRITE, tmp_entries,
|
|
tmp.entry_ct*sizeof(struct unipair)))
|
|
return -EFAULT;
|
|
switch (cmd) {
|
|
case PIO_UNIMAP:
|
|
if (!perm)
|
|
return -EPERM;
|
|
return con_set_unimap(vc, tmp.entry_ct, tmp_entries);
|
|
case GIO_UNIMAP:
|
|
if (!perm && fg_console != vc->vc_num)
|
|
return -EPERM;
|
|
return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp_entries);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
long vt_compat_ioctl(struct tty_struct *tty,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
struct vc_data *vc = tty->driver_data;
|
|
struct console_font_op op; /* used in multiple places here */
|
|
unsigned int console;
|
|
void __user *up = (void __user *)arg;
|
|
int perm;
|
|
int ret = 0;
|
|
|
|
console = vc->vc_num;
|
|
|
|
if (!vc_cons_allocated(console)) { /* impossible? */
|
|
ret = -ENOIOCTLCMD;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* To have permissions to do most of the vt ioctls, we either have
|
|
* to be the owner of the tty, or have CAP_SYS_TTY_CONFIG.
|
|
*/
|
|
perm = 0;
|
|
if (current->signal->tty == tty || capable(CAP_SYS_TTY_CONFIG))
|
|
perm = 1;
|
|
|
|
switch (cmd) {
|
|
/*
|
|
* these need special handlers for incompatible data structures
|
|
*/
|
|
case PIO_FONTX:
|
|
case GIO_FONTX:
|
|
ret = compat_fontx_ioctl(cmd, up, perm, &op);
|
|
break;
|
|
|
|
case KDFONTOP:
|
|
ret = compat_kdfontop_ioctl(up, perm, &op, vc);
|
|
break;
|
|
|
|
case PIO_UNIMAP:
|
|
case GIO_UNIMAP:
|
|
ret = compat_unimap_ioctl(cmd, up, perm, vc);
|
|
break;
|
|
|
|
/*
|
|
* all these treat 'arg' as an integer
|
|
*/
|
|
case KIOCSOUND:
|
|
case KDMKTONE:
|
|
#ifdef CONFIG_X86
|
|
case KDADDIO:
|
|
case KDDELIO:
|
|
#endif
|
|
case KDSETMODE:
|
|
case KDMAPDISP:
|
|
case KDUNMAPDISP:
|
|
case KDSKBMODE:
|
|
case KDSKBMETA:
|
|
case KDSKBLED:
|
|
case KDSETLED:
|
|
case KDSIGACCEPT:
|
|
case VT_ACTIVATE:
|
|
case VT_WAITACTIVE:
|
|
case VT_RELDISP:
|
|
case VT_DISALLOCATE:
|
|
case VT_RESIZE:
|
|
case VT_RESIZEX:
|
|
goto fallback;
|
|
|
|
/*
|
|
* the rest has a compatible data structure behind arg,
|
|
* but we have to convert it to a proper 64 bit pointer.
|
|
*/
|
|
default:
|
|
arg = (unsigned long)compat_ptr(arg);
|
|
goto fallback;
|
|
}
|
|
out:
|
|
return ret;
|
|
|
|
fallback:
|
|
return vt_ioctl(tty, cmd, arg);
|
|
}
|
|
|
|
|
|
#endif /* CONFIG_COMPAT */
|
|
|
|
|
|
/*
|
|
* Performs the back end of a vt switch. Called under the console
|
|
* semaphore.
|
|
*/
|
|
static void complete_change_console(struct vc_data *vc)
|
|
{
|
|
unsigned char old_vc_mode;
|
|
int old = fg_console;
|
|
|
|
last_console = fg_console;
|
|
|
|
/*
|
|
* If we're switching, we could be going from KD_GRAPHICS to
|
|
* KD_TEXT mode or vice versa, which means we need to blank or
|
|
* unblank the screen later.
|
|
*/
|
|
old_vc_mode = vc_cons[fg_console].d->vc_mode;
|
|
switch_screen(vc);
|
|
|
|
/*
|
|
* This can't appear below a successful kill_pid(). If it did,
|
|
* then the *blank_screen operation could occur while X, having
|
|
* received acqsig, is waking up on another processor. This
|
|
* condition can lead to overlapping accesses to the VGA range
|
|
* and the framebuffer (causing system lockups).
|
|
*
|
|
* To account for this we duplicate this code below only if the
|
|
* controlling process is gone and we've called reset_vc.
|
|
*/
|
|
if (old_vc_mode != vc->vc_mode) {
|
|
if (vc->vc_mode == KD_TEXT)
|
|
do_unblank_screen(1);
|
|
else
|
|
do_blank_screen(1);
|
|
}
|
|
|
|
/*
|
|
* If this new console is under process control, send it a signal
|
|
* telling it that it has acquired. Also check if it has died and
|
|
* clean up (similar to logic employed in change_console())
|
|
*/
|
|
if (vc->vt_mode.mode == VT_PROCESS) {
|
|
/*
|
|
* Send the signal as privileged - kill_pid() will
|
|
* tell us if the process has gone or something else
|
|
* is awry
|
|
*/
|
|
if (kill_pid(vc->vt_pid, vc->vt_mode.acqsig, 1) != 0) {
|
|
/*
|
|
* The controlling process has died, so we revert back to
|
|
* normal operation. In this case, we'll also change back
|
|
* to KD_TEXT mode. I'm not sure if this is strictly correct
|
|
* but it saves the agony when the X server dies and the screen
|
|
* remains blanked due to KD_GRAPHICS! It would be nice to do
|
|
* this outside of VT_PROCESS but there is no single process
|
|
* to account for and tracking tty count may be undesirable.
|
|
*/
|
|
reset_vc(vc);
|
|
|
|
if (old_vc_mode != vc->vc_mode) {
|
|
if (vc->vc_mode == KD_TEXT)
|
|
do_unblank_screen(1);
|
|
else
|
|
do_blank_screen(1);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Wake anyone waiting for their VT to activate
|
|
*/
|
|
vt_event_post(VT_EVENT_SWITCH, old, vc->vc_num);
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* Performs the front-end of a vt switch
|
|
*/
|
|
void change_console(struct vc_data *new_vc)
|
|
{
|
|
struct vc_data *vc;
|
|
|
|
if (!new_vc || new_vc->vc_num == fg_console || vt_dont_switch)
|
|
return;
|
|
|
|
/*
|
|
* If this vt is in process mode, then we need to handshake with
|
|
* that process before switching. Essentially, we store where that
|
|
* vt wants to switch to and wait for it to tell us when it's done
|
|
* (via VT_RELDISP ioctl).
|
|
*
|
|
* We also check to see if the controlling process still exists.
|
|
* If it doesn't, we reset this vt to auto mode and continue.
|
|
* This is a cheap way to track process control. The worst thing
|
|
* that can happen is: we send a signal to a process, it dies, and
|
|
* the switch gets "lost" waiting for a response; hopefully, the
|
|
* user will try again, we'll detect the process is gone (unless
|
|
* the user waits just the right amount of time :-) and revert the
|
|
* vt to auto control.
|
|
*/
|
|
vc = vc_cons[fg_console].d;
|
|
if (vc->vt_mode.mode == VT_PROCESS) {
|
|
/*
|
|
* Send the signal as privileged - kill_pid() will
|
|
* tell us if the process has gone or something else
|
|
* is awry.
|
|
*
|
|
* We need to set vt_newvt *before* sending the signal or we
|
|
* have a race.
|
|
*/
|
|
vc->vt_newvt = new_vc->vc_num;
|
|
if (kill_pid(vc->vt_pid, vc->vt_mode.relsig, 1) == 0) {
|
|
/*
|
|
* It worked. Mark the vt to switch to and
|
|
* return. The process needs to send us a
|
|
* VT_RELDISP ioctl to complete the switch.
|
|
*/
|
|
return;
|
|
}
|
|
|
|
/*
|
|
* The controlling process has died, so we revert back to
|
|
* normal operation. In this case, we'll also change back
|
|
* to KD_TEXT mode. I'm not sure if this is strictly correct
|
|
* but it saves the agony when the X server dies and the screen
|
|
* remains blanked due to KD_GRAPHICS! It would be nice to do
|
|
* this outside of VT_PROCESS but there is no single process
|
|
* to account for and tracking tty count may be undesirable.
|
|
*/
|
|
reset_vc(vc);
|
|
|
|
/*
|
|
* Fall through to normal (VT_AUTO) handling of the switch...
|
|
*/
|
|
}
|
|
|
|
/*
|
|
* Ignore all switches in KD_GRAPHICS+VT_AUTO mode
|
|
*/
|
|
if (vc->vc_mode == KD_GRAPHICS)
|
|
return;
|
|
|
|
complete_change_console(new_vc);
|
|
}
|
|
|
|
/* Perform a kernel triggered VT switch for suspend/resume */
|
|
|
|
static int disable_vt_switch;
|
|
|
|
int vt_move_to_console(unsigned int vt, int alloc)
|
|
{
|
|
int prev;
|
|
|
|
console_lock();
|
|
/* Graphics mode - up to X */
|
|
if (disable_vt_switch) {
|
|
console_unlock();
|
|
return 0;
|
|
}
|
|
prev = fg_console;
|
|
|
|
if (alloc && vc_allocate(vt)) {
|
|
/* we can't have a free VC for now. Too bad,
|
|
* we don't want to mess the screen for now. */
|
|
console_unlock();
|
|
return -ENOSPC;
|
|
}
|
|
|
|
if (set_console(vt)) {
|
|
/*
|
|
* We're unable to switch to the SUSPEND_CONSOLE.
|
|
* Let the calling function know so it can decide
|
|
* what to do.
|
|
*/
|
|
console_unlock();
|
|
return -EIO;
|
|
}
|
|
console_unlock();
|
|
if (vt_waitactive(vt + 1)) {
|
|
pr_debug("Suspend: Can't switch VCs.");
|
|
return -EINTR;
|
|
}
|
|
return prev;
|
|
}
|
|
|
|
/*
|
|
* Normally during a suspend, we allocate a new console and switch to it.
|
|
* When we resume, we switch back to the original console. This switch
|
|
* can be slow, so on systems where the framebuffer can handle restoration
|
|
* of video registers anyways, there's little point in doing the console
|
|
* switch. This function allows you to disable it by passing it '0'.
|
|
*/
|
|
void pm_set_vt_switch(int do_switch)
|
|
{
|
|
console_lock();
|
|
disable_vt_switch = !do_switch;
|
|
console_unlock();
|
|
}
|
|
EXPORT_SYMBOL(pm_set_vt_switch);
|