tty: Add EXTPROC support for LINEMODE

This patch is against the 2.6.34 source.

Paraphrased from the 1989 BSD patch by David Borman @ cray.com:

     These are the changes needed for the kernel to support
     LINEMODE in the server.

     There is a new bit in the termios local flag word, EXTPROC.
     When this bit is set, several aspects of the terminal driver
     are disabled.  Input line editing, character echo, and mapping
     of signals are all disabled.  This allows the telnetd to turn
     off these functions when in linemode, but still keep track of
     what state the user wants the terminal to be in.

     New ioctl:
         TIOCSIG         Generate a signal to processes in the
                         current process group of the pty.

     There is a new mode for packet driver, the TIOCPKT_IOCTL bit.
     When packet mode is turned on in the pty, and the EXTPROC bit
     is set, then whenever the state of the pty is changed, the
     next read on the master side of the pty will have the TIOCPKT_IOCTL
     bit set.  This allows the process on the server side of the pty
     to know when the state of the terminal has changed; it can then
     issue the appropriate ioctl to retrieve the new state.

Since the original BSD patches accompanied the source code for telnet
I've left that reference here, but obviously the feature is useful for
any remote terminal protocol, including ssh.

The corresponding feature has existed in the BSD tty driver since 1989.
For historical reference, a good copy of the relevant files can be found
here:

http://anonsvn.mit.edu/viewvc/krb5/trunk/src/appl/telnet/?pathrev=17741

Signed-off-by: Howard Chu <hyc@symas.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

39 files changed, 101 insertions, 10 deletions

diff --git a/arch/alpha/include/asm/ioctls.h b/arch/alpha/include/asm/ioctls.h
index c7b0cc61ce5b..59617c3c2be6 100644
--- a/arch/alpha/include/asm/ioctls.h
+++ b/arch/alpha/include/asm/ioctls.h
@@ -80,6 +80,7 @@
 # define TIOCPKT_START		 8
 # define TIOCPKT_NOSTOP		16
 # define TIOCPKT_DOSTOP		32
+# define TIOCPKT_IOCTL		64
 
 
 #define TIOCNOTTY	0x5422
@@ -91,6 +92,7 @@
 #define TIOCGSID	0x5429  /* Return the session ID of FD */
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define TIOCSERCONFIG	0x5453
 #define TIOCSERGWILD	0x5454
diff --git a/arch/alpha/include/asm/termbits.h b/arch/alpha/include/asm/termbits.h
index ad854a4a3af6..879dd3589921 100644
--- a/arch/alpha/include/asm/termbits.h
+++ b/arch/alpha/include/asm/termbits.h
@@ -180,6 +180,7 @@ struct ktermios {
 #define FLUSHO	0x00800000
 #define PENDIN	0x20000000
 #define IEXTEN	0x00000400
+#define EXTPROC	0x10000000
 
 /* Values for the ACTION argument to `tcflow'.  */
 #define	TCOOFF		0
diff --git a/arch/arm/include/asm/ioctls.h b/arch/arm/include/asm/ioctls.h
index 7f0b6d13296a..0b30894b5482 100644
--- a/arch/arm/include/asm/ioctls.h
+++ b/arch/arm/include/asm/ioctls.h
@@ -52,6 +52,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define TIOCGRS485      0x542E
 #define TIOCSRS485      0x542F
@@ -81,6 +82,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT	0x01	/* Transmitter physically empty */
 
diff --git a/arch/arm/include/asm/termbits.h b/arch/arm/include/asm/termbits.h
index f784d11f40b5..704135d28d1d 100644
--- a/arch/arm/include/asm/termbits.h
+++ b/arch/arm/include/asm/termbits.h
@@ -177,6 +177,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 /* tcflow() and TCXONC use these */
 #define	TCOOFF		0
diff --git a/arch/avr32/include/asm/ioctls.h b/arch/avr32/include/asm/ioctls.h
index 143dafb3997e..b7dd324b46a9 100644
--- a/arch/avr32/include/asm/ioctls.h
+++ b/arch/avr32/include/asm/ioctls.h
@@ -53,6 +53,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define TIOCGRS485      0x542E
 #define TIOCSRS485      0x542F
@@ -82,6 +83,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
 
diff --git a/arch/avr32/include/asm/termbits.h b/arch/avr32/include/asm/termbits.h
index db2daab31fdb..366adc5ebb10 100644
--- a/arch/avr32/include/asm/termbits.h
+++ b/arch/avr32/include/asm/termbits.h
@@ -175,6 +175,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 /* tcflow() and TCXONC use these */
 #define	TCOOFF		0
diff --git a/arch/cris/include/asm/ioctls.h b/arch/cris/include/asm/ioctls.h
index bb49142dc6ab..c9129ed37443 100644
--- a/arch/cris/include/asm/ioctls.h
+++ b/arch/cris/include/asm/ioctls.h
@@ -54,6 +54,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define FIONCLEX	0x5450  /* these numbers need to be adjusted. */
 #define FIOCLEX		0x5451
@@ -85,6 +86,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
 
diff --git a/arch/cris/include/asm/termbits.h b/arch/cris/include/asm/termbits.h
index 66e1a7492a0c..1c43bc874ccf 100644
--- a/arch/cris/include/asm/termbits.h
+++ b/arch/cris/include/asm/termbits.h
@@ -214,6 +214,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 /* tcflow() and TCXONC use these */
 #define	TCOOFF		0
diff --git a/arch/frv/include/asm/ioctls.h b/arch/frv/include/asm/ioctls.h
index d0c30e31fbda..a993e3759ccf 100644
--- a/arch/frv/include/asm/ioctls.h
+++ b/arch/frv/include/asm/ioctls.h
@@ -53,6 +53,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define FIONCLEX	0x5450  /* these numbers need to be adjusted. */
 #define FIOCLEX		0x5451
@@ -79,6 +80,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
 
diff --git a/arch/frv/include/asm/termbits.h b/arch/frv/include/asm/termbits.h
index 5568492b5086..7722e19cc349 100644
--- a/arch/frv/include/asm/termbits.h
+++ b/arch/frv/include/asm/termbits.h
@@ -180,6 +180,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 
 /* tcflow() and TCXONC use these */
diff --git a/arch/h8300/include/asm/ioctls.h b/arch/h8300/include/asm/ioctls.h
index 98a53d067269..b6b249f9f308 100644
--- a/arch/h8300/include/asm/ioctls.h
+++ b/arch/h8300/include/asm/ioctls.h
@@ -53,6 +53,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define FIONCLEX	0x5450  /* these numbers need to be adjusted. */
 #define FIOCLEX		0x5451
@@ -79,6 +80,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
 
diff --git a/arch/h8300/include/asm/termbits.h b/arch/h8300/include/asm/termbits.h
index 31eca81db3f7..3287a6244d74 100644
--- a/arch/h8300/include/asm/termbits.h
+++ b/arch/h8300/include/asm/termbits.h
@@ -179,6 +179,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 
 /* tcflow() and TCXONC use these */
diff --git a/arch/ia64/include/asm/ioctls.h b/arch/ia64/include/asm/ioctls.h
index f0ee86c0b5f7..b79c385114ef 100644
--- a/arch/ia64/include/asm/ioctls.h
+++ b/arch/ia64/include/asm/ioctls.h
@@ -59,6 +59,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define FIONCLEX	0x5450  /* these numbers need to be adjusted. */
 #define FIOCLEX		0x5451
@@ -85,6 +86,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
 
diff --git a/arch/ia64/include/asm/termbits.h b/arch/ia64/include/asm/termbits.h
index 9f162e0089ad..c009b94e58d9 100644
--- a/arch/ia64/include/asm/termbits.h
+++ b/arch/ia64/include/asm/termbits.h
@@ -187,6 +187,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 /* tcflow() and TCXONC use these */
 #define	TCOOFF		0
diff --git a/arch/m32r/include/asm/ioctls.h b/arch/m32r/include/asm/ioctls.h
index f4c13a52fe48..66288063a4c0 100644
--- a/arch/m32r/include/asm/ioctls.h
+++ b/arch/m32r/include/asm/ioctls.h
@@ -53,6 +53,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define FIONCLEX	0x5450
 #define FIOCLEX		0x5451
@@ -79,6 +80,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
 
diff --git a/arch/m32r/include/asm/termbits.h b/arch/m32r/include/asm/termbits.h
index bc104008b55b..957a3c688549 100644
--- a/arch/m32r/include/asm/termbits.h
+++ b/arch/m32r/include/asm/termbits.h
@@ -179,6 +179,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 /* tcflow() and TCXONC use these */
 #define	TCOOFF		0
diff --git a/arch/m68k/include/asm/ioctls.h b/arch/m68k/include/asm/ioctls.h
index b8d2f4be7fd7..91a57d665460 100644
--- a/arch/m68k/include/asm/ioctls.h
+++ b/arch/m68k/include/asm/ioctls.h
@@ -52,6 +52,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define FIONCLEX	0x5450  /* these numbers need to be adjusted. */
 #define FIOCLEX		0x5451
@@ -78,6 +79,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
 
diff --git a/arch/m68k/include/asm/termbits.h b/arch/m68k/include/asm/termbits.h
index 8c14170996bb..aea1e37b765a 100644
--- a/arch/m68k/include/asm/termbits.h
+++ b/arch/m68k/include/asm/termbits.h
@@ -179,6 +179,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 
 /* tcflow() and TCXONC use these */
diff --git a/arch/mips/include/asm/ioctls.h b/arch/mips/include/asm/ioctls.h
index 2fb9e1693bf7..d87cb0465693 100644
--- a/arch/mips/include/asm/ioctls.h
+++ b/arch/mips/include/asm/ioctls.h
@@ -41,7 +41,7 @@
 #define	 TIOCPKT_START		0x08	/* start output */
 #define	 TIOCPKT_NOSTOP		0x10	/* no more ^S, ^Q */
 #define	 TIOCPKT_DOSTOP		0x20	/* now do ^S ^Q */
-/* #define  TIOCPKT_IOCTL		0x40	state change of pty driver */
+#define  TIOCPKT_IOCTL		0x40	/* state change of pty driver */
 #define TIOCSWINSZ	_IOW('t', 103, struct winsize)	/* set window size */
 #define TIOCGWINSZ	_IOR('t', 104, struct winsize)	/* get window size */
 #define TIOCNOTTY	0x5471		/* void tty association */
@@ -83,6 +83,7 @@
 #define TCSETSF2	_IOW('T', 0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T', 0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T', 0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T', 0x36, int)  /* Generate signal on Pty slave */
 
 /* I hope the range from 0x5480 on is free ... */
 #define TIOCSCTTY	0x5480		/* become controlling tty */
diff --git a/arch/mips/include/asm/termbits.h b/arch/mips/include/asm/termbits.h
index c83c68444e86..76630b396fac 100644
--- a/arch/mips/include/asm/termbits.h
+++ b/arch/mips/include/asm/termbits.h
@@ -203,6 +203,7 @@ struct ktermios {
 #define PENDIN	0040000		/* Retype pending input (state).  */
 #define TOSTOP	0100000		/* Send SIGTTOU for background output.  */
 #define ITOSTOP	TOSTOP
+#define EXTPROC	0200000		/* External processing on pty */
 
 /* ioctl (fd, TIOCSERGETLSR, &result) where result may be as below */
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
diff --git a/arch/mn10300/include/asm/ioctls.h b/arch/mn10300/include/asm/ioctls.h
index 638219a99b1e..cb8cf1902234 100644
--- a/arch/mn10300/include/asm/ioctls.h
+++ b/arch/mn10300/include/asm/ioctls.h
@@ -54,6 +54,7 @@
 #define TIOCGPTN	_IOR('T', 0x30, unsigned int) /* Get Pty Number
 						       * (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T', 0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T', 0x36, int)  /* Generate signal on Pty slave */
 
 #define FIONCLEX	0x5450
 #define FIOCLEX		0x5451
@@ -80,6 +81,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
 
diff --git a/arch/mn10300/include/asm/termbits.h b/arch/mn10300/include/asm/termbits.h
index eb2b0dc1f696..130d42495972 100644
--- a/arch/mn10300/include/asm/termbits.h
+++ b/arch/mn10300/include/asm/termbits.h
@@ -180,6 +180,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 /* tcflow() and TCXONC use these */
 #define	TCOOFF		0
diff --git a/arch/parisc/include/asm/ioctls.h b/arch/parisc/include/asm/ioctls.h
index 6cc497e52532..4e0614456bea 100644
--- a/arch/parisc/include/asm/ioctls.h
+++ b/arch/parisc/include/asm/ioctls.h
@@ -52,6 +52,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define FIONCLEX	0x5450  /* these numbers need to be adjusted. */
 #define FIOCLEX		0x5451
@@ -82,6 +83,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
 
diff --git a/arch/parisc/include/asm/termbits.h b/arch/parisc/include/asm/termbits.h
index d8bbc73b16b7..d1ab92177a5c 100644
--- a/arch/parisc/include/asm/termbits.h
+++ b/arch/parisc/include/asm/termbits.h
@@ -180,6 +180,7 @@ struct ktermios {
 #define FLUSHO  0010000
 #define PENDIN  0040000
 #define IEXTEN  0100000
+#define EXTPROC	0200000
 
 /* tcflow() and TCXONC use these */
 #define	TCOOFF		0
diff --git a/arch/powerpc/include/asm/ioctls.h b/arch/powerpc/include/asm/ioctls.h
index 1842186d872c..851920052e08 100644
--- a/arch/powerpc/include/asm/ioctls.h
+++ b/arch/powerpc/include/asm/ioctls.h
@@ -80,6 +80,7 @@
 # define TIOCPKT_START		 8
 # define TIOCPKT_NOSTOP		16
 # define TIOCPKT_DOSTOP		32
+# define TIOCPKT_IOCTL		64
 
 
 #define TIOCNOTTY	0x5422
@@ -93,6 +94,7 @@
 #define TIOCSRS485	0x542f
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define TIOCSERCONFIG	0x5453
 #define TIOCSERGWILD	0x5454
diff --git a/arch/powerpc/include/asm/termbits.h b/arch/powerpc/include/asm/termbits.h
index 6698188ca550..549d700e18f2 100644
--- a/arch/powerpc/include/asm/termbits.h
+++ b/arch/powerpc/include/asm/termbits.h
@@ -189,6 +189,7 @@ struct ktermios {
 #define FLUSHO	0x00800000
 #define PENDIN	0x20000000
 #define IEXTEN	0x00000400
+#define EXTPROC	0x10000000
 
 /* Values for the ACTION argument to `tcflow'.  */
 #define	TCOOFF		0
diff --git a/arch/s390/include/asm/ioctls.h b/arch/s390/include/asm/ioctls.h
index 40e481b1b461..2f3d8736361f 100644
--- a/arch/s390/include/asm/ioctls.h
+++ b/arch/s390/include/asm/ioctls.h
@@ -60,6 +60,7 @@
 #define TCSETSF2	_IOW('T',0x2D, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define FIONCLEX	0x5450  /* these numbers need to be adjusted. */
 #define FIOCLEX		0x5451
@@ -86,6 +87,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT    0x01	/* Transmitter physically empty */
 
diff --git a/arch/sh/include/asm/ioctls.h b/arch/sh/include/asm/ioctls.h
index c212c371a4a5..eb6c4c687972 100644
--- a/arch/sh/include/asm/ioctls.h
+++ b/arch/sh/include/asm/ioctls.h
@@ -69,6 +69,7 @@
 # define TIOCPKT_START		 8
 # define TIOCPKT_NOSTOP		16
 # define TIOCPKT_DOSTOP		32
+# define TIOCPKT_IOCTL		64
 
 
 #define TIOCNOTTY	_IO('T', 34) /* 0x5422 */
@@ -84,6 +85,7 @@
 #define TCSETSF2	_IOW('T', 45, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #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 1fe6855c5c18..53f4ee009bdd 100644
--- a/arch/sparc/include/asm/ioctls.h
+++ b/arch/sparc/include/asm/ioctls.h
@@ -80,6 +80,7 @@
 /* Get minor device of a pty master's FD -- Solaris equiv is ISPTM */
 #define TIOCGPTN	_IOR('t', 134, unsigned int) /* Get Pty Number */
 #define TIOCSPTLCK	_IOW('t', 135, int) /* Lock/unlock PTY */
+#define TIOCSIG		_IOW('t', 136, int) /* Generate signal on Pty slave */
 
 /* Little f */
 #define FIOCLEX		_IO('f', 1)
@@ -132,5 +133,6 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #endif /* !(_ASM_SPARC_IOCTLS_H) */
diff --git a/arch/sparc/include/asm/termbits.h b/arch/sparc/include/asm/termbits.h
index d72dfed1f9d7..23b10ff08df2 100644
--- a/arch/sparc/include/asm/termbits.h
+++ b/arch/sparc/include/asm/termbits.h
@@ -225,6 +225,7 @@ struct ktermios {
 #define FLUSHO	0x00002000
 #define PENDIN	0x00004000
 #define IEXTEN	0x00008000
+#define EXTPROC	0x00010000
 
 /* modem lines */
 #define TIOCM_LE	0x001
diff --git a/arch/xtensa/include/asm/ioctls.h b/arch/xtensa/include/asm/ioctls.h
index 0ffa942954b9..ab1800012ed9 100644
--- a/arch/xtensa/include/asm/ioctls.h
+++ b/arch/xtensa/include/asm/ioctls.h
@@ -81,6 +81,7 @@
 # define TIOCPKT_START		 8
 # define TIOCPKT_NOSTOP		16
 # define TIOCPKT_DOSTOP		32
+# define TIOCPKT_IOCTL		64
 
 
 #define TIOCNOTTY	_IO('T', 34)
@@ -97,6 +98,7 @@
 #define TCSETSF2	_IOW('T', 45, struct termios2)
 #define TIOCGPTN	_IOR('T',0x30, unsigned int) /* Get Pty Number (of pty-mux device) */
 #define TIOCSPTLCK	_IOW('T',0x31, int)  /* Lock/unlock Pty */
+#define TIOCSIG		_IOW('T',0x36, int)  /* Generate signal on Pty slave */
 
 #define TIOCSERCONFIG	_IO('T', 83)
 #define TIOCSERGWILD	_IOR('T', 84,  int)
diff --git a/arch/xtensa/include/asm/termbits.h b/arch/xtensa/include/asm/termbits.h
index 85aa6a3c0b6e..0d6c8715b24f 100644
--- a/arch/xtensa/include/asm/termbits.h
+++ b/arch/xtensa/include/asm/termbits.h
@@ -196,6 +196,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 /* tcflow() and TCXONC use these */
 
diff --git a/drivers/char/n_tty.c b/drivers/char/n_tty.c
index bdae8327143c..428f4fe0b5f7 100644
--- a/drivers/char/n_tty.c
+++ b/drivers/char/n_tty.c
@@ -1102,6 +1102,11 @@ static inline void n_tty_receive_char(struct tty_struct *tty, unsigned char c)
 	if (I_IUCLC(tty) && L_IEXTEN(tty))
 		c = tolower(c);
 
+	if (L_EXTPROC(tty)) {
+		put_tty_queue(c, tty);
+		return;
+	}
+
 	if (tty->stopped && !tty->flow_stopped && I_IXON(tty) &&
 	    I_IXANY(tty) && c != START_CHAR(tty) && c != STOP_CHAR(tty) &&
 	    c != INTR_CHAR(tty) && c != QUIT_CHAR(tty) && c != SUSP_CHAR(tty)) {
@@ -1409,7 +1414,8 @@ static void n_tty_receive_buf(struct tty_struct *tty, const unsigned char *cp,
 
 	n_tty_set_room(tty);
 
-	if (!tty->icanon && (tty->read_cnt >= tty->minimum_to_wake)) {
+	if ((!tty->icanon && (tty->read_cnt >= tty->minimum_to_wake)) ||
+		L_EXTPROC(tty)) {
 		kill_fasync(&tty->fasync, SIGIO, POLL_IN);
 		if (waitqueue_active(&tty->read_wait))
 			wake_up_interruptible(&tty->read_wait);
@@ -1585,7 +1591,7 @@ static int n_tty_open(struct tty_struct *tty)
 static inline int input_available_p(struct tty_struct *tty, int amt)
 {
 	tty_flush_to_ldisc(tty);
-	if (tty->icanon) {
+	if (tty->icanon && !L_EXTPROC(tty)) {
 		if (tty->canon_data)
 			return 1;
 	} else if (tty->read_cnt >= (amt ? amt : 1))
@@ -1632,6 +1638,11 @@ static int copy_from_read_buf(struct tty_struct *tty,
 		spin_lock_irqsave(&tty->read_lock, flags);
 		tty->read_tail = (tty->read_tail + n) & (N_TTY_BUF_SIZE-1);
 		tty->read_cnt -= n;
+		/* Turn single EOF into zero-length read */
+		if (L_EXTPROC(tty) && tty->icanon && n == 1) {
+			if (!tty->read_cnt && (*b)[n-1] == EOF_CHAR(tty))
+				n--;
+		}
 		spin_unlock_irqrestore(&tty->read_lock, flags);
 		*b += n;
 		*nr -= n;
@@ -1812,7 +1823,7 @@ do_it_again:
 			nr--;
 		}
 
-		if (tty->icanon) {
+		if (tty->icanon && !L_EXTPROC(tty)) {
 			/* N.B. avoid overrun if nr == 0 */
 			while (nr && tty->read_cnt) {
 				int eol;
diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index d83a43130df4..b640ef29be1c 100644
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -171,6 +171,23 @@ static int pty_set_lock(struct tty_struct *tty, int __user *arg)
 	return 0;
 }
 
+/* Send a signal to the slave */
+static int pty_signal(struct tty_struct *tty, int sig)
+{
+	unsigned long flags;
+	struct pid *pgrp;
+
+	if (tty->link) {
+		spin_lock_irqsave(&tty->link->ctrl_lock, flags);
+		pgrp = get_pid(tty->link->pgrp);
+		spin_unlock_irqrestore(&tty->link->ctrl_lock, flags);
+
+		kill_pgrp(pgrp, sig, 1);
+		put_pid(pgrp);
+	}
+	return 0;
+}
+
 static void pty_flush_buffer(struct tty_struct *tty)
 {
 	struct tty_struct *to = tty->link;
@@ -321,6 +338,8 @@ static int pty_bsd_ioctl(struct tty_struct *tty, struct file *file,
 	switch (cmd) {
 	case TIOCSPTLCK: /* Set PT Lock (disallow slave open) */
 		return pty_set_lock(tty, (int __user *) arg);
+	case TIOCSIG:    /* Send signal to other side of pty */
+		return pty_signal(tty, (int) arg);
 	}
 	return -ENOIOCTLCMD;
 }
@@ -476,6 +495,8 @@ static int pty_unix98_ioctl(struct tty_struct *tty, struct file *file,
 		return pty_set_lock(tty, (int __user *)arg);
 	case TIOCGPTN: /* Get PT Number */
 		return put_user(tty->index, (unsigned int __user *)arg);
+	case TIOCSIG:    /* Send signal to other side of pty */
+		return pty_signal(tty, (int) arg);
 	}
 
 	return -ENOIOCTLCMD;
diff --git a/drivers/char/tty_ioctl.c b/drivers/char/tty_ioctl.c
index 6bd5f8866c74..0c1889971459 100644
--- a/drivers/char/tty_ioctl.c
+++ b/drivers/char/tty_ioctl.c
@@ -517,19 +517,25 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
 
 	/* See if packet mode change of state. */
 	if (tty->link && tty->link->packet) {
+		int extproc = (old_termios.c_lflag & EXTPROC) |
+				(tty->termios->c_lflag & EXTPROC);
 		int old_flow = ((old_termios.c_iflag & IXON) &&
 				(old_termios.c_cc[VSTOP] == '\023') &&
 				(old_termios.c_cc[VSTART] == '\021'));
 		int new_flow = (I_IXON(tty) &&
 				STOP_CHAR(tty) == '\023' &&
 				START_CHAR(tty) == '\021');
-		if (old_flow != new_flow) {
+		if ((old_flow != new_flow) || extproc) {
 			spin_lock_irqsave(&tty->ctrl_lock, flags);
-			tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
-			if (new_flow)
-				tty->ctrl_status |= TIOCPKT_DOSTOP;
-			else
-				tty->ctrl_status |= TIOCPKT_NOSTOP;
+			if (old_flow != new_flow) {
+				tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
+				if (new_flow)
+					tty->ctrl_status |= TIOCPKT_DOSTOP;
+				else
+					tty->ctrl_status |= TIOCPKT_NOSTOP;
+			}
+			if (extproc)
+				tty->ctrl_status |= TIOCPKT_IOCTL;
 			spin_unlock_irqrestore(&tty->ctrl_lock, flags);
 			wake_up_interruptible(&tty->link->read_wait);
 		}
diff --git a/fs/compat_ioctl.c b/fs/compat_ioctl.c
index 63ae85831464..fa4bc48810fd 100644
--- a/fs/compat_ioctl.c
+++ b/fs/compat_ioctl.c
@@ -969,6 +969,7 @@ COMPATIBLE_IOCTL(TIOCGPGRP)
 COMPATIBLE_IOCTL(TIOCGPTN)
 COMPATIBLE_IOCTL(TIOCSPTLCK)
 COMPATIBLE_IOCTL(TIOCSERGETLSR)
+COMPATIBLE_IOCTL(TIOCSIG)
 #ifdef TCGETS2
 COMPATIBLE_IOCTL(TCGETS2)
 COMPATIBLE_IOCTL(TCSETS2)
diff --git a/include/asm-generic/ioctls.h b/include/asm-generic/ioctls.h
index 1375fa1a7a4d..8554cb6a81b9 100644
--- a/include/asm-generic/ioctls.h
+++ b/include/asm-generic/ioctls.h
@@ -69,6 +69,7 @@
 #define TCSETX		0x5433
 #define TCSETXF		0x5434
 #define TCSETXW		0x5435
+#define TIOCSIG		_IOW('T', 0x36, int)  /* pty: generate signal */
 
 #define FIONCLEX	0x5450
 #define FIOCLEX		0x5451
@@ -102,6 +103,7 @@
 #define TIOCPKT_START		 8
 #define TIOCPKT_NOSTOP		16
 #define TIOCPKT_DOSTOP		32
+#define TIOCPKT_IOCTL		64
 
 #define TIOCSER_TEMT	0x01	/* Transmitter physically empty */
 
diff --git a/include/asm-generic/termbits.h b/include/asm-generic/termbits.h
index 1c9773d48cb0..232b4781aef3 100644
--- a/include/asm-generic/termbits.h
+++ b/include/asm-generic/termbits.h
@@ -178,6 +178,7 @@ struct ktermios {
 #define FLUSHO	0010000
 #define PENDIN	0040000
 #define IEXTEN	0100000
+#define EXTPROC	0200000
 
 /* tcflow() and TCXONC use these */
 #define	TCOOFF		0
diff --git a/include/linux/tty.h b/include/linux/tty.h
index 7802a243ee13..2df60e4ff40e 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -179,6 +179,7 @@ struct tty_bufhead {
 #define L_FLUSHO(tty)	_L_FLAG((tty), FLUSHO)
 #define L_PENDIN(tty)	_L_FLAG((tty), PENDIN)
 #define L_IEXTEN(tty)	_L_FLAG((tty), IEXTEN)
+#define L_EXTPROC(tty)	_L_FLAG((tty), EXTPROC)
 
 struct device;
 struct signal_struct;