alistair23-linux/drivers/char/vt_ioctl.c
Arnd Bergmann 2c4e9671ed Input: use PIT_TICK_RATE in vt beep ioctl
The KIOCSOUND and KDMKTONE ioctls are based on the CLOCK_TICK_RATE,
which is architecture and sometimes configuration specific.

In practice, most user applications assume that it is actually defined
as the i8253 PIT base clock of 1193182 Hz, which is true on some
architectures but not on others.

This patch makes the vt code use the PIT frequency on all
architectures, which is much more well-defined.  It will change the
behavior of user applications sending the beep ioctl on all
architectures that define CLOCK_TICK_RATE different from
PIT_TICK_RATE.

The original breakage was introduced in commit bcc8ca099 "Adapt
drivers/char/vt_ioctl.c to non-x86".  Hopefully, reverting this change
will make the frequency correct in more cases than it will make it
incorrect.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
2010-08-28 21:39:09 -07:00

1788 lines
40 KiB
C

/*
* linux/drivers/char/vt_ioctl.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/smp_lock.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);
}
/**
* 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)
{
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);
/* Wait for it to pass */
wait_event_interruptible_tty(vt_event_waitqueue, vw->done);
/* Dequeue it */
spin_lock_irqsave(&vt_event_lock, flags);
list_del(&vw->list);
spin_unlock_irqrestore(&vt_event_lock, flags);
}
/**
* 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 {
if (n == fg_console + 1)
break;
vw.event.event = VT_EVENT_SWITCH;
vt_event_wait(&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)
#define i (tmp.kb_index)
#define s (tmp.kb_table)
#define v (tmp.kb_value)
static inline int
do_kdsk_ioctl(int cmd, struct kbentry __user *user_kbe, int perm, struct kbd_struct *kbd)
{
struct kbentry tmp;
ushort *key_map, val, ov;
if (copy_from_user(&tmp, user_kbe, sizeof(struct kbentry)))
return -EFAULT;
if (!capable(CAP_SYS_TTY_CONFIG))
perm = 0;
switch (cmd) {
case KDGKBENT:
key_map = key_maps[s];
if (key_map) {
val = U(key_map[i]);
if (kbd->kbdmode != VC_UNICODE && KTYP(val) >= NR_TYPES)
val = K_HOLE;
} else
val = (i ? K_HOLE : K_NOSUCHMAP);
return put_user(val, &user_kbe->kb_value);
case KDSKBENT:
if (!perm)
return -EPERM;
if (!i && v == K_NOSUCHMAP) {
/* deallocate map */
key_map = key_maps[s];
if (s && key_map) {
key_maps[s] = NULL;
if (key_map[0] == U(K_ALLOCATED)) {
kfree(key_map);
keymap_count--;
}
}
break;
}
if (KTYP(v) < NR_TYPES) {
if (KVAL(v) > max_vals[KTYP(v)])
return -EINVAL;
} else
if (kbd->kbdmode != VC_UNICODE)
return -EINVAL;
/* ++Geert: non-PC keyboards may generate keycode zero */
#if !defined(__mc68000__) && !defined(__powerpc__)
/* assignment to entry 0 only tests validity of args */
if (!i)
break;
#endif
if (!(key_map = key_maps[s])) {
int j;
if (keymap_count >= MAX_NR_OF_USER_KEYMAPS &&
!capable(CAP_SYS_RESOURCE))
return -EPERM;
key_map = kmalloc(sizeof(plain_map),
GFP_KERNEL);
if (!key_map)
return -ENOMEM;
key_maps[s] = key_map;
key_map[0] = U(K_ALLOCATED);
for (j = 1; j < NR_KEYS; j++)
key_map[j] = U(K_HOLE);
keymap_count++;
}
ov = U(key_map[i]);
if (v == ov)
break; /* nothing to do */
/*
* Attention Key.
*/
if (((ov == K_SAK) || (v == K_SAK)) && !capable(CAP_SYS_ADMIN))
return -EPERM;
key_map[i] = U(v);
if (!s && (KTYP(ov) == KT_SHIFT || KTYP(v) == KT_SHIFT))
compute_shiftstate();
break;
}
return 0;
}
#undef i
#undef s
#undef v
static inline int
do_kbkeycode_ioctl(int cmd, struct kbkeycode __user *user_kbkc, int perm)
{
struct kbkeycode tmp;
int kc = 0;
if (copy_from_user(&tmp, user_kbkc, sizeof(struct kbkeycode)))
return -EFAULT;
switch (cmd) {
case KDGETKEYCODE:
kc = getkeycode(tmp.scancode);
if (kc >= 0)
kc = put_user(kc, &user_kbkc->keycode);
break;
case KDSETKEYCODE:
if (!perm)
return -EPERM;
kc = setkeycode(tmp.scancode, tmp.keycode);
break;
}
return kc;
}
static inline int
do_kdgkb_ioctl(int cmd, struct kbsentry __user *user_kdgkb, int perm)
{
struct kbsentry *kbs;
char *p;
u_char *q;
u_char __user *up;
int sz;
int delta;
char *first_free, *fj, *fnw;
int i, j, k;
int ret;
if (!capable(CAP_SYS_TTY_CONFIG))
perm = 0;
kbs = kmalloc(sizeof(*kbs), GFP_KERNEL);
if (!kbs) {
ret = -ENOMEM;
goto reterr;
}
/* we mostly copy too much here (512bytes), but who cares ;) */
if (copy_from_user(kbs, user_kdgkb, sizeof(struct kbsentry))) {
ret = -EFAULT;
goto reterr;
}
kbs->kb_string[sizeof(kbs->kb_string)-1] = '\0';
i = kbs->kb_func;
switch (cmd) {
case KDGKBSENT:
sz = sizeof(kbs->kb_string) - 1; /* sz should have been
a struct member */
up = user_kdgkb->kb_string;
p = func_table[i];
if(p)
for ( ; *p && sz; p++, sz--)
if (put_user(*p, up++)) {
ret = -EFAULT;
goto reterr;
}
if (put_user('\0', up)) {
ret = -EFAULT;
goto reterr;
}
kfree(kbs);
return ((p && *p) ? -EOVERFLOW : 0);
case KDSKBSENT:
if (!perm) {
ret = -EPERM;
goto reterr;
}
q = func_table[i];
first_free = funcbufptr + (funcbufsize - funcbufleft);
for (j = i+1; j < MAX_NR_FUNC && !func_table[j]; j++)
;
if (j < MAX_NR_FUNC)
fj = func_table[j];
else
fj = first_free;
delta = (q ? -strlen(q) : 1) + strlen(kbs->kb_string);
if (delta <= funcbufleft) { /* it fits in current buf */
if (j < MAX_NR_FUNC) {
memmove(fj + delta, fj, first_free - fj);
for (k = j; k < MAX_NR_FUNC; k++)
if (func_table[k])
func_table[k] += delta;
}
if (!q)
func_table[i] = fj;
funcbufleft -= delta;
} else { /* allocate a larger buffer */
sz = 256;
while (sz < funcbufsize - funcbufleft + delta)
sz <<= 1;
fnw = kmalloc(sz, GFP_KERNEL);
if(!fnw) {
ret = -ENOMEM;
goto reterr;
}
if (!q)
func_table[i] = fj;
if (fj > funcbufptr)
memmove(fnw, funcbufptr, fj - funcbufptr);
for (k = 0; k < j; k++)
if (func_table[k])
func_table[k] = fnw + (func_table[k] - funcbufptr);
if (first_free > fj) {
memmove(fnw + (fj - funcbufptr) + delta, fj, first_free - fj);
for (k = j; k < MAX_NR_FUNC; k++)
if (func_table[k])
func_table[k] = fnw + (func_table[k] - funcbufptr) + delta;
}
if (funcbufptr != func_buf)
kfree(funcbufptr);
funcbufptr = fnw;
funcbufleft = funcbufleft - delta + sz - funcbufsize;
funcbufsize = sz;
}
strcpy(func_table[i], kbs->kb_string);
break;
}
ret = 0;
reterr:
kfree(kbs);
return ret;
}
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;
}
/*
* 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, struct file * file,
unsigned int cmd, unsigned long arg)
{
struct vc_data *vc = tty->driver_data;
struct console_font_op op; /* used in multiple places here */
struct kbd_struct * kbd;
unsigned int console;
unsigned char ucval;
void __user *up = (void __user *)arg;
int i, perm;
int ret = 0;
console = vc->vc_num;
tty_lock();
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;
kbd = kbd_table + console;
switch (cmd) {
case TIOCLINUX:
ret = tioclinux(tty, arg);
break;
case KIOCSOUND:
if (!perm)
goto 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.
*/
if (arg)
arg = PIT_TICK_RATE / arg;
kd_mksound(arg, 0);
break;
case KDMKTONE:
if (!perm)
goto 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 naive.
*/
ucval = KB_101;
goto setchar;
/*
* 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...
*/
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))
goto 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)
goto 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;
}
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
*/
acquire_console_sem();
if (arg == KD_TEXT)
do_unblank_screen(1);
else
do_blank_screen(1);
release_console_sem();
break;
case KDGETMODE:
ucval = 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)
goto eperm;
switch(arg) {
case K_RAW:
kbd->kbdmode = VC_RAW;
break;
case K_MEDIUMRAW:
kbd->kbdmode = VC_MEDIUMRAW;
break;
case K_XLATE:
kbd->kbdmode = VC_XLATE;
compute_shiftstate();
break;
case K_UNICODE:
kbd->kbdmode = VC_UNICODE;
compute_shiftstate();
break;
default:
ret = -EINVAL;
goto out;
}
tty_ldisc_flush(tty);
break;
case KDGKBMODE:
ucval = ((kbd->kbdmode == VC_RAW) ? K_RAW :
(kbd->kbdmode == VC_MEDIUMRAW) ? K_MEDIUMRAW :
(kbd->kbdmode == VC_UNICODE) ? K_UNICODE :
K_XLATE);
goto setint;
/* this could be folded into KDSKBMODE, but for compatibility
reasons it is not so easy to fold KDGKBMETA into KDGKBMODE */
case KDSKBMETA:
switch(arg) {
case K_METABIT:
clr_vc_kbd_mode(kbd, VC_META);
break;
case K_ESCPREFIX:
set_vc_kbd_mode(kbd, VC_META);
break;
default:
ret = -EINVAL;
}
break;
case KDGKBMETA:
ucval = (vc_kbd_mode(kbd, VC_META) ? K_ESCPREFIX : K_METABIT);
setint:
ret = put_user(ucval, (int __user *)arg);
break;
case KDGETKEYCODE:
case KDSETKEYCODE:
if(!capable(CAP_SYS_TTY_CONFIG))
perm = 0;
ret = do_kbkeycode_ioctl(cmd, up, perm);
break;
case KDGKBENT:
case KDSKBENT:
ret = do_kdsk_ioctl(cmd, up, perm, kbd);
break;
case KDGKBSENT:
case KDSKBSENT:
ret = do_kdgkb_ioctl(cmd, up, perm);
break;
case KDGKBDIACR:
{
struct kbdiacrs __user *a = up;
struct kbdiacr diacr;
int i;
if (put_user(accent_table_size, &a->kb_cnt)) {
ret = -EFAULT;
break;
}
for (i = 0; i < accent_table_size; i++) {
diacr.diacr = conv_uni_to_8bit(accent_table[i].diacr);
diacr.base = conv_uni_to_8bit(accent_table[i].base);
diacr.result = conv_uni_to_8bit(accent_table[i].result);
if (copy_to_user(a->kbdiacr + i, &diacr, sizeof(struct kbdiacr))) {
ret = -EFAULT;
break;
}
}
break;
}
case KDGKBDIACRUC:
{
struct kbdiacrsuc __user *a = up;
if (put_user(accent_table_size, &a->kb_cnt))
ret = -EFAULT;
else if (copy_to_user(a->kbdiacruc, accent_table,
accent_table_size*sizeof(struct kbdiacruc)))
ret = -EFAULT;
break;
}
case KDSKBDIACR:
{
struct kbdiacrs __user *a = up;
struct kbdiacr diacr;
unsigned int ct;
int i;
if (!perm)
goto eperm;
if (get_user(ct,&a->kb_cnt)) {
ret = -EFAULT;
break;
}
if (ct >= MAX_DIACR) {
ret = -EINVAL;
break;
}
accent_table_size = ct;
for (i = 0; i < ct; i++) {
if (copy_from_user(&diacr, a->kbdiacr + i, sizeof(struct kbdiacr))) {
ret = -EFAULT;
break;
}
accent_table[i].diacr = conv_8bit_to_uni(diacr.diacr);
accent_table[i].base = conv_8bit_to_uni(diacr.base);
accent_table[i].result = conv_8bit_to_uni(diacr.result);
}
break;
}
case KDSKBDIACRUC:
{
struct kbdiacrsuc __user *a = up;
unsigned int ct;
if (!perm)
goto eperm;
if (get_user(ct,&a->kb_cnt)) {
ret = -EFAULT;
break;
}
if (ct >= MAX_DIACR) {
ret = -EINVAL;
break;
}
accent_table_size = ct;
if (copy_from_user(accent_table, a->kbdiacruc, ct*sizeof(struct kbdiacruc)))
ret = -EFAULT;
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:
ucval = kbd->ledflagstate | (kbd->default_ledflagstate << 4);
goto setchar;
case KDSKBLED:
if (!perm)
goto eperm;
if (arg & ~0x77) {
ret = -EINVAL;
break;
}
kbd->ledflagstate = (arg & 7);
kbd->default_ledflagstate = ((arg >> 4) & 7);
set_leds();
break;
/* the ioctls below only set the lights, not the functions */
/* for those, see KDGKBLED and KDSKBLED above */
case KDGETLED:
ucval = getledstate();
setchar:
ret = put_user(ucval, (char __user *)arg);
break;
case KDSETLED:
if (!perm)
goto eperm;
setledstate(kbd, arg);
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))
goto 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)
goto 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;
}
acquire_console_sem();
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;
release_console_sem();
break;
}
case VT_GETMODE:
{
struct vt_mode tmp;
int rc;
acquire_console_sem();
memcpy(&tmp, &vc->vt_mode, sizeof(struct vt_mode));
release_console_sem();
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;
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:
for (i = 0; i < MAX_NR_CONSOLES; ++i)
if (! VT_IS_IN_USE(i))
break;
ucval = 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)
goto eperm;
if (arg == 0 || arg > MAX_NR_CONSOLES)
ret = -ENXIO;
else {
arg--;
acquire_console_sem();
ret = vc_allocate(arg);
release_console_sem();
if (ret)
break;
set_console(arg);
}
break;
case VT_SETACTIVATE:
{
struct vt_setactivate vsa;
if (!perm)
goto 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--;
acquire_console_sem();
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));
}
release_console_sem();
if (ret)
break;
/* Commence switch and lock */
set_console(arg);
}
}
/*
* wait until the specified VT has been activated
*/
case VT_WAITACTIVE:
if (!perm)
goto 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)
goto eperm;
if (vc->vt_mode.mode != VT_PROCESS) {
ret = -EINVAL;
break;
}
/*
* Switching-from response
*/
acquire_console_sem();
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) {
release_console_sem();
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;
}
release_console_sem();
break;
/*
* Disallocate memory associated to VT (but leave VT1)
*/
case VT_DISALLOCATE:
if (arg > MAX_NR_CONSOLES) {
ret = -ENXIO;
break;
}
if (arg == 0) {
/* deallocate all unused consoles, but leave 0 */
acquire_console_sem();
for (i=1; i<MAX_NR_CONSOLES; i++)
if (! VT_BUSY(i))
vc_deallocate(i);
release_console_sem();
} else {
/* deallocate a single console, if possible */
arg--;
if (VT_BUSY(arg))
ret = -EBUSY;
else if (arg) { /* leave 0 */
acquire_console_sem();
vc_deallocate(arg);
release_console_sem();
}
}
break;
case VT_RESIZE:
{
struct vt_sizes __user *vtsizes = up;
struct vc_data *vc;
ushort ll,cc;
if (!perm)
goto eperm;
if (get_user(ll, &vtsizes->v_rows) ||
get_user(cc, &vtsizes->v_cols))
ret = -EFAULT;
else {
acquire_console_sem();
for (i = 0; i < MAX_NR_CONSOLES; i++) {
vc = vc_cons[i].d;
if (vc) {
vc->vc_resize_user = 1;
vc_resize(vc_cons[i].d, cc, ll);
}
}
release_console_sem();
}
break;
}
case VT_RESIZEX:
{
struct vt_consize __user *vtconsize = up;
ushort ll,cc,vlin,clin,vcol,ccol;
if (!perm)
goto 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;
acquire_console_sem();
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);
release_console_sem();
}
break;
}
case PIO_FONT: {
if (!perm)
goto 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)
goto 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;
con_set_default_unimap(vc_cons[fg_console].d);
break;
}
#endif
}
case KDFONTOP: {
if (copy_from_user(&op, up, sizeof(op))) {
ret = -EFAULT;
break;
}
if (!perm && op.op != KD_FONT_OP_GET)
goto 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)
goto 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))
goto eperm;
vt_dont_switch = 1;
break;
case VT_UNLOCKSWITCH:
if (!capable(CAP_SYS_TTY_CONFIG))
goto 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:
tty_unlock();
return ret;
eperm:
ret = -EPERM;
goto out;
}
void reset_vc(struct vc_data *vc)
{
vc->vc_mode = KD_TEXT;
kbd_table[vc->vc_num].kbdmode = default_utf8 ? VC_UNICODE : VC_XLATE;
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;
acquire_console_sem();
vc = vc_con->d;
if (vc) {
tty = vc->port.tty;
/*
* SAK should also work in all raw modes and reset
* them properly.
*/
if (tty)
__do_SAK(tty);
reset_vc(vc);
}
release_console_sem();
}
#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);
op->flags |= KD_FONT_FLAG_OLD;
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, struct file * file,
unsigned int cmd, unsigned long arg)
{
struct vc_data *vc = tty->driver_data;
struct console_font_op op; /* used in multiple places here */
struct kbd_struct *kbd;
unsigned int console;
void __user *up = (void __user *)arg;
int perm;
int ret = 0;
console = vc->vc_num;
tty_lock();
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;
kbd = kbd_table + console;
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:
tty_unlock();
return ret;
fallback:
tty_unlock();
return vt_ioctl(tty, file, 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;
acquire_console_sem();
/* Graphics mode - up to X */
if (disable_vt_switch) {
release_console_sem();
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. */
release_console_sem();
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.
*/
release_console_sem();
return -EIO;
}
release_console_sem();
tty_lock();
if (vt_waitactive(vt + 1)) {
pr_debug("Suspend: Can't switch VCs.");
tty_unlock();
return -EINTR;
}
tty_unlock();
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)
{
acquire_console_sem();
disable_vt_switch = !do_switch;
release_console_sem();
}
EXPORT_SYMBOL(pm_set_vt_switch);