kernel-ark/drivers/char/vt_ioctl.c
Eric W. Biederman bde0d2c98b [PATCH] vt: Make vt_pid a struct pid (making it pid wrap around safe).
I took a good hard look at the locking and it appears the locking on vt_pid
is the console semaphore.  Every modified path is called under the console
semaphore except reset_vc when it is called from fn_SAK or do_SAK both of
which appear to be in interrupt context.  In addition I need to be careful
because in the presence of an oops the console_sem may be arbitrarily
dropped.

Which leads me to conclude the current locking is inadequate for my needs.

Given the weird cases we could hit because of oops printing instead of
introducing an extra spin lock to protect the data and keep the pid to
signal and the signal to send in sync, I have opted to use xchg on just the
struct pid * pointer instead.

Due to console_sem we will stay in sync between vt_pid and vt_mode except
for a small window during a SAK, or oops handling.  SAK handling should
kill any user space process that care, and oops handling we are broken
anyway.  Besides the worst that can happen is that I try to send the wrong
signal.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-02 07:57:14 -07:00

1211 lines
28 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/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/signal.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>
static 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);
/*
* 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 = (ushort *) 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 = (char *) 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 = (struct vc_data *)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;
console = vc->vc_num;
if (!vc_cons_allocated(console)) /* impossible? */
return -ENOIOCTLCMD;
/*
* 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 KIOCSOUND:
if (!perm)
return -EPERM;
if (arg)
arg = CLOCK_TICK_RATE / arg;
kd_mksound(arg, 0);
return 0;
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 = CLOCK_TICK_RATE / count;
kd_mksound(count, ticks);
return 0;
}
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)
return -EINVAL;
return sys_ioperm(arg, 1, (cmd == KDADDIO)) ? -ENXIO : 0;
case KDENABIO:
case KDDISABIO:
return sys_ioperm(GPFIRST, GPNUM,
(cmd == KDENABIO)) ? -ENXIO : 0;
#endif
/* Linux m68k/i386 interface for setting the keyboard delay/repeat rate */
case KDKBDREP:
{
struct kbd_repeat kbrep;
int err;
if (!capable(CAP_SYS_TTY_CONFIG))
return -EPERM;
if (copy_from_user(&kbrep, up, sizeof(struct kbd_repeat)))
return -EFAULT;
err = kbd_rate(&kbrep);
if (err)
return err;
if (copy_to_user(up, &kbrep, sizeof(struct kbd_repeat)))
return -EFAULT;
return 0;
}
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:
return -EINVAL;
}
if (vc->vc_mode == (unsigned char) arg)
return 0;
vc->vc_mode = (unsigned char) arg;
if (console != fg_console)
return 0;
/*
* 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();
return 0;
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.
*/
return -EINVAL;
case KDSKBMODE:
if (!perm)
return -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:
return -EINVAL;
}
tty_ldisc_flush(tty);
return 0;
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:
return -EINVAL;
}
return 0;
case KDGKBMETA:
ucval = (vc_kbd_mode(kbd, VC_META) ? K_ESCPREFIX : K_METABIT);
setint:
return put_user(ucval, (int __user *)arg);
case KDGETKEYCODE:
case KDSETKEYCODE:
if(!capable(CAP_SYS_TTY_CONFIG))
perm=0;
return do_kbkeycode_ioctl(cmd, up, perm);
case KDGKBENT:
case KDSKBENT:
return do_kdsk_ioctl(cmd, up, perm, kbd);
case KDGKBSENT:
case KDSKBSENT:
return do_kdgkb_ioctl(cmd, up, perm);
case KDGKBDIACR:
{
struct kbdiacrs __user *a = up;
if (put_user(accent_table_size, &a->kb_cnt))
return -EFAULT;
if (copy_to_user(a->kbdiacr, accent_table, accent_table_size*sizeof(struct kbdiacr)))
return -EFAULT;
return 0;
}
case KDSKBDIACR:
{
struct kbdiacrs __user *a = up;
unsigned int ct;
if (!perm)
return -EPERM;
if (get_user(ct,&a->kb_cnt))
return -EFAULT;
if (ct >= MAX_DIACR)
return -EINVAL;
accent_table_size = ct;
if (copy_from_user(accent_table, a->kbdiacr, ct*sizeof(struct kbdiacr)))
return -EFAULT;
return 0;
}
/* 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)
return -EPERM;
if (arg & ~0x77)
return -EINVAL;
kbd->ledflagstate = (arg & 7);
kbd->default_ledflagstate = ((arg >> 4) & 7);
set_leds();
return 0;
/* the ioctls below only set the lights, not the functions */
/* for those, see KDGKBLED and KDSKBLED above */
case KDGETLED:
ucval = getledstate();
setchar:
return put_user(ucval, (char __user *)arg);
case KDSETLED:
if (!perm)
return -EPERM;
setledstate(kbd, arg);
return 0;
/*
* 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)
return -EINVAL;
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);
return 0;
}
case VT_SETMODE:
{
struct vt_mode tmp;
if (!perm)
return -EPERM;
if (copy_from_user(&tmp, up, sizeof(struct vt_mode)))
return -EFAULT;
if (tmp.mode != VT_AUTO && tmp.mode != VT_PROCESS)
return -EINVAL;
acquire_console_sem();
vc->vt_mode = tmp;
/* the frsig is ignored, so we set it to 0 */
vc->vt_mode.frsig = 0;
put_pid(xchg(&vc->vt_pid, get_pid(task_pid(current))));
/* no switch is required -- saw@shade.msu.ru */
vc->vt_newvt = -1;
release_console_sem();
return 0;
}
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));
return rc ? -EFAULT : 0;
}
/*
* 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))
return -EFAULT;
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;
return put_user(state, &vtstat->v_state);
}
/*
* 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)
return -EPERM;
if (arg == 0 || arg > MAX_NR_CONSOLES)
return -ENXIO;
arg--;
acquire_console_sem();
i = vc_allocate(arg);
release_console_sem();
if (i)
return i;
set_console(arg);
return 0;
/*
* wait until the specified VT has been activated
*/
case VT_WAITACTIVE:
if (!perm)
return -EPERM;
if (arg == 0 || arg > MAX_NR_CONSOLES)
return -ENXIO;
return vt_waitactive(arg-1);
/*
* 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;
if (vc->vt_mode.mode != VT_PROCESS)
return -EINVAL;
/*
* 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;
acquire_console_sem();
newvt = vc->vt_newvt;
vc->vt_newvt = -1;
i = vc_allocate(newvt);
if (i) {
release_console_sem();
return i;
}
/*
* 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);
release_console_sem();
}
}
/*
* Switched-to response
*/
else
{
/*
* If it's just an ACK, ignore it
*/
if (arg != VT_ACKACQ)
return -EINVAL;
}
return 0;
/*
* Disallocate memory associated to VT (but leave VT1)
*/
case VT_DISALLOCATE:
if (arg > MAX_NR_CONSOLES)
return -ENXIO;
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))
return -EBUSY;
if (arg) { /* leave 0 */
acquire_console_sem();
vc_deallocate(arg);
release_console_sem();
}
}
return 0;
case VT_RESIZE:
{
struct vt_sizes __user *vtsizes = up;
ushort ll,cc;
if (!perm)
return -EPERM;
if (get_user(ll, &vtsizes->v_rows) ||
get_user(cc, &vtsizes->v_cols))
return -EFAULT;
for (i = 0; i < MAX_NR_CONSOLES; i++)
vc_lock_resize(vc_cons[i].d, cc, ll);
return 0;
}
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)))
return -EFAULT;
__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)
return -EINVAL; /* Parameters don't add up */
} else
ll = vlin/clin;
}
if (vcol && ccol) {
if (cc) {
if (cc != vcol/ccol)
return -EINVAL;
} else
cc = vcol/ccol;
}
if (clin > 32)
return -EINVAL;
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_resize(vc_cons[i].d, cc, ll);
release_console_sem();
}
return 0;
}
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;
return con_font_op(vc_cons[fg_console].d, &op);
}
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;
return con_font_op(vc_cons[fg_console].d, &op);
}
case PIO_CMAP:
if (!perm)
return -EPERM;
return con_set_cmap(up);
case GIO_CMAP:
return con_get_cmap(up);
case PIO_FONTX:
case GIO_FONTX:
return do_fontx_ioctl(cmd, up, perm, &op);
case PIO_FONTRESET:
{
if (!perm)
return -EPERM;
#ifdef BROKEN_GRAPHICS_PROGRAMS
/* With BROKEN_GRAPHICS_PROGRAMS defined, the default
font is not saved. */
return -ENOSYS;
#else
{
op.op = KD_FONT_OP_SET_DEFAULT;
op.data = NULL;
i = con_font_op(vc_cons[fg_console].d, &op);
if (i)
return i;
con_set_default_unimap(vc_cons[fg_console].d);
return 0;
}
#endif
}
case KDFONTOP: {
if (copy_from_user(&op, up, sizeof(op)))
return -EFAULT;
if (!perm && op.op != KD_FONT_OP_GET)
return -EPERM;
i = con_font_op(vc, &op);
if (i) return i;
if (copy_to_user(up, &op, sizeof(op)))
return -EFAULT;
return 0;
}
case PIO_SCRNMAP:
if (!perm)
return -EPERM;
return con_set_trans_old(up);
case GIO_SCRNMAP:
return con_get_trans_old(up);
case PIO_UNISCRNMAP:
if (!perm)
return -EPERM;
return con_set_trans_new(up);
case GIO_UNISCRNMAP:
return con_get_trans_new(up);
case PIO_UNIMAPCLR:
{ struct unimapinit ui;
if (!perm)
return -EPERM;
i = copy_from_user(&ui, up, sizeof(struct unimapinit));
if (i) return -EFAULT;
con_clear_unimap(vc, &ui);
return 0;
}
case PIO_UNIMAP:
case GIO_UNIMAP:
return do_unimap_ioctl(cmd, up, perm, vc);
case VT_LOCKSWITCH:
if (!capable(CAP_SYS_TTY_CONFIG))
return -EPERM;
vt_dont_switch = 1;
return 0;
case VT_UNLOCKSWITCH:
if (!capable(CAP_SYS_TTY_CONFIG))
return -EPERM;
vt_dont_switch = 0;
return 0;
case VT_GETHIFONTMASK:
return put_user(vc->vc_hi_font_mask, (unsigned short __user *)arg);
default:
return -ENOIOCTLCMD;
}
}
/*
* Sometimes we want to wait until a particular VT has been activated. We
* do it in a very simple manner. Everybody waits on a single queue and
* get woken up at once. Those that are satisfied go on with their business,
* while those not ready go back to sleep. Seems overkill to add a wait
* to each vt just for this - usually this does nothing!
*/
static DECLARE_WAIT_QUEUE_HEAD(vt_activate_queue);
/*
* Sleeps until a vt is activated, or the task is interrupted. Returns
* 0 if activation, -EINTR if interrupted.
*/
int vt_waitactive(int vt)
{
int retval;
DECLARE_WAITQUEUE(wait, current);
add_wait_queue(&vt_activate_queue, &wait);
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
retval = 0;
if (vt == fg_console)
break;
retval = -EINTR;
if (signal_pending(current))
break;
schedule();
}
remove_wait_queue(&vt_activate_queue, &wait);
current->state = TASK_RUNNING;
return retval;
}
#define vt_wake_waitactive() wake_up(&vt_activate_queue)
void reset_vc(struct vc_data *vc)
{
vc->vc_mode = KD_TEXT;
kbd_table[vc->vc_num].kbdmode = 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(xchg(&vc->vt_pid, NULL));
vc->vt_newvt = -1;
if (!in_interrupt()) /* Via keyboard.c:SAK() - akpm */
reset_palette(vc);
}
/*
* Performs the back end of a vt switch
*/
static void complete_change_console(struct vc_data *vc)
{
unsigned char old_vc_mode;
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_proc(). 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_proc() 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_wake_waitactive();
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_proc() will
* tell us if the process has gone or something else
* is awry
*/
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.
*/
vc->vt_newvt = new_vc->vc_num;
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);
}