tty: add TIOCVHANGUP to allow clean tty shutdown of all ttys

This is useful for system management software so that it can kick
off things like gettys and everything that's started from a tty,
before we reuse it from/for something else or shut it down.

Without this ioctl it would have to temporarily become the owner of
the tty, then call vhangup() and then give it up again.

Cc: Lennart Poettering <lennart@poettering.net>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

9 files changed, 13 insertions, 0 deletions

diff --git a/arch/alpha/include/asm/ioctls.h b/arch/alpha/include/asm/ioctls.h
index 034b6cf5d9f3..80e1cee90f1f 100644
--- a/arch/alpha/include/asm/ioctls.h
+++ b/arch/alpha/include/asm/ioctls.h
@@ -94,6 +94,7 @@
 #define TIOCSPTLCK      _IOW('T',0x31, int)  /* Lock/unlock Pty */
 #define TIOCGDEV        _IOR('T',0x32, unsigned int) /* Get primary device node of /dev/console */
 #define TIOCSIG         _IOW('T',0x36, int)  /* Generate signal on Pty slave */
+#define TIOCVHANGUP     0x5437
 
 #define TIOCSERCONFIG   0x5453
 #define TIOCSERGWILD    0x5454
diff --git a/arch/mips/include/asm/ioctls.h b/arch/mips/include/asm/ioctls.h
index d967b8997626..92403c3d6007 100644
--- a/arch/mips/include/asm/ioctls.h
+++ b/arch/mips/include/asm/ioctls.h
@@ -85,6 +85,7 @@
 #define TIOCSPTLCK      _IOW('T', 0x31, int)  /* Lock/unlock Pty */
 #define TIOCGDEV        _IOR('T', 0x32, unsigned int) /* Get primary device node of /dev/console */
 #define TIOCSIG         _IOW('T', 0x36, int)  /* Generate signal on Pty slave */
+#define TIOCVHANGUP     0x5437
 
 /* I hope the range from 0x5480 on is free ... */
 #define TIOCSCTTY       0x5480          /* become controlling tty */
diff --git a/arch/parisc/include/asm/ioctls.h b/arch/parisc/include/asm/ioctls.h
index 6ba80d03623a..054ec06f9e23 100644
--- a/arch/parisc/include/asm/ioctls.h
+++ b/arch/parisc/include/asm/ioctls.h
@@ -54,6 +54,7 @@
 #define TIOCSPTLCK      _IOW('T',0x31, int)  /* Lock/unlock Pty */
 #define TIOCGDEV        _IOR('T',0x32, int)  /* Get primary device node of /dev/console */
 #define TIOCSIG         _IOW('T',0x36, int)  /* Generate signal on Pty slave */
+#define TIOCVHANGUP     0x5437
 
 #define FIONCLEX        0x5450  /* these numbers need to be adjusted. */
 #define FIOCLEX         0x5451
diff --git a/arch/powerpc/include/asm/ioctls.h b/arch/powerpc/include/asm/ioctls.h
index c7dc17cf84f1..e9b78870aaab 100644
--- a/arch/powerpc/include/asm/ioctls.h
+++ b/arch/powerpc/include/asm/ioctls.h
@@ -96,6 +96,7 @@
 #define TIOCSPTLCK      _IOW('T',0x31, int)  /* Lock/unlock Pty */
 #define TIOCGDEV        _IOR('T',0x32, unsigned int) /* Get primary device node of /dev/console */
 #define TIOCSIG         _IOW('T',0x36, int)  /* Generate signal on Pty slave */
+#define TIOCVHANGUP     0x5437
 
 #define TIOCSERCONFIG   0x5453
 #define TIOCSERGWILD    0x5454
diff --git a/arch/sh/include/asm/ioctls.h b/arch/sh/include/asm/ioctls.h
index 84e85a792638..a6769f352bf6 100644
--- a/arch/sh/include/asm/ioctls.h
+++ b/arch/sh/include/asm/ioctls.h
@@ -87,6 +87,7 @@
 #define TIOCSPTLCK      _IOW('T',0x31, int)  /* Lock/unlock Pty */
 #define TIOCGDEV        _IOR('T',0x32, unsigned int) /* Get primary device node of /dev/console */
 #define TIOCSIG         _IOW('T',0x36, int)  /* Generate signal on Pty slave */
+#define TIOCVHANGUP     _IO('T', 0x37)
 
 #define TIOCSERCONFIG   _IO('T', 83) /* 0x5453 */
 #define TIOCSERGWILD    _IOR('T', 84,  int) /* 0x5454 */
diff --git a/arch/sparc/include/asm/ioctls.h b/arch/sparc/include/asm/ioctls.h
index ed3807b96bb5..28d0c8b02cc3 100644
--- a/arch/sparc/include/asm/ioctls.h
+++ b/arch/sparc/include/asm/ioctls.h
@@ -20,6 +20,7 @@
 #define TCSETSW2        _IOW('T', 14, struct termios2)
 #define TCSETSF2        _IOW('T', 15, struct termios2)
 #define TIOCGDEV        _IOR('T',0x32, unsigned int) /* Get primary device node of /dev/console */
+#define TIOCVHANGUP     _IO('T', 0x37)
 
 /* Note that all the ioctls that are not available in Linux have a 
  * double underscore on the front to: a) avoid some programs to
diff --git a/arch/xtensa/include/asm/ioctls.h b/arch/xtensa/include/asm/ioctls.h
index ccf1800f0b0c..fd1d1369a407 100644
--- a/arch/xtensa/include/asm/ioctls.h
+++ b/arch/xtensa/include/asm/ioctls.h
@@ -100,6 +100,7 @@
 #define TIOCSPTLCK      _IOW('T',0x31, int)  /* Lock/unlock Pty */
 #define TIOCGDEV        _IOR('T',0x32, unsigned int) /* Get primary device node of /dev/console */
 #define TIOCSIG         _IOW('T',0x36, int)  /* Generate signal on Pty slave */
+#define TIOCVHANGUP     _IO('T', 0x37)
 
 #define TIOCSERCONFIG   _IO('T', 83)
 #define TIOCSERGWILD    _IOR('T', 84,  int)
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 20a862a2a0c2..8ef2d69470ec 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -2626,6 +2626,11 @@ long tty_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
                 return put_user(tty->ldisc->ops->num, (int __user *)p);
         case TIOCSETD:
                 return tiocsetd(tty, p);
+        case TIOCVHANGUP:
+                if (!capable(CAP_SYS_ADMIN))
+                        return -EPERM;
+                tty_vhangup(tty);
+                return 0;
         case TIOCGDEV:
         {
                 unsigned int ret = new_encode_dev(tty_devnum(real_tty));
diff --git a/include/asm-generic/ioctls.h b/include/asm-generic/ioctls.h
index 3f3f2d189fb8..199975fac395 100644
--- a/include/asm-generic/ioctls.h
+++ b/include/asm-generic/ioctls.h
@@ -73,6 +73,7 @@
 #define TCSETXF         0x5434
 #define TCSETXW         0x5435
 #define TIOCSIG         _IOW('T', 0x36, int)  /* pty: generate signal */
+#define TIOCVHANGUP     0x5437
 
 #define FIONCLEX        0x5450
 #define FIOCLEX         0x5451