arch/alpha, termios: implement BOTHER, IBSHIFT and termios2

commit d0ffb805b729322626639336986bc83fc2e60871 upstream.

Alpha has had c_ispeed and c_ospeed, but still set speeds in c_cflags
using arbitrary flags. Because BOTHER is not defined, the general
Linux code doesn't allow setting arbitrary baud rates, and because
CBAUDEX == 0, we can have an array overrun of the baud_rate[] table in
drivers/tty/tty_baudrate.c if (c_cflags & CBAUD) == 037.

Resolve both problems by #defining BOTHER to 037 on Alpha.

However, userspace still needs to know if setting BOTHER is actually
safe given legacy kernels (does anyone actually care about that on
Alpha anymore?), so enable the TCGETS2/TCSETS*2 ioctls on Alpha, even
though they use the same structure. Define struct termios2 just for
compatibility; it is the exact same structure as struct termios. In a
future patchset, this will be cleaned up so the uapi headers are
usable from libc.

Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Cc: Eugene Syromiatnikov <esyr@redhat.com>
Cc: <linux-alpha@vger.kernel.org>
Cc: <linux-serial@vger.kernel.org>
Cc: Johan Hovold <johan@kernel.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/alpha/include/asm/termios.h b/arch/alpha/include/asm/termios.h
index 7fde0f88da888b8cf52a0bc636cce4b655ef518e..51ed90be770a8f065b9d1ac3f0488d246344127c 100644 (file)
--- a/arch/alpha/include/asm/termios.h
+++ b/arch/alpha/include/asm/termios.h
@@ -72,9 +72,15 @@
 })
 
 #define user_termios_to_kernel_termios(k, u) \
-       copy_from_user(k, u, sizeof(struct termios))
+       copy_from_user(k, u, sizeof(struct termios2))
 
 #define kernel_termios_to_user_termios(u, k) \
+       copy_to_user(u, k, sizeof(struct termios2))
+
+#define user_termios_to_kernel_termios_1(k, u) \
+       copy_from_user(k, u, sizeof(struct termios))
+
+#define kernel_termios_to_user_termios_1(u, k) \
        copy_to_user(u, k, sizeof(struct termios))
 
 #endif /* _ALPHA_TERMIOS_H */

diff --git a/arch/alpha/include/uapi/asm/ioctls.h b/arch/alpha/include/uapi/asm/ioctls.h
index f30c94ae1bdb19499af9b21c0006f06f6756d43f..7ee8ab577e115cc7639649ca84dbf0d9dda51bcf 100644 (file)
--- a/arch/alpha/include/uapi/asm/ioctls.h
+++ b/arch/alpha/include/uapi/asm/ioctls.h
@@ -31,6 +31,11 @@
 #define TCXONC         _IO('t', 30)
 #define TCFLSH         _IO('t', 31)
 
+#define TCGETS2                _IOR('T', 42, struct termios2)
+#define TCSETS2                _IOW('T', 43, struct termios2)
+#define TCSETSW2       _IOW('T', 44, struct termios2)
+#define TCSETSF2       _IOW('T', 45, struct termios2)
+
 #define TIOCSWINSZ     _IOW('t', 103, struct winsize)
 #define TIOCGWINSZ     _IOR('t', 104, struct winsize)
 #define        TIOCSTART       _IO('t', 110)           /* start output, like ^Q */

diff --git a/arch/alpha/include/uapi/asm/termbits.h b/arch/alpha/include/uapi/asm/termbits.h
index 879dd35899218b850e154f64c4477375ca804432..483c7ec2a8795fe288eca4a60b675fa0f44c26ed 100644 (file)
--- a/arch/alpha/include/uapi/asm/termbits.h
+++ b/arch/alpha/include/uapi/asm/termbits.h
@@ -25,6 +25,19 @@ struct termios {
        speed_t c_ospeed;               /* output speed */
 };
 
+/* Alpha has identical termios and termios2 */
+
+struct termios2 {
+       tcflag_t c_iflag;               /* input mode flags */
+       tcflag_t c_oflag;               /* output mode flags */
+       tcflag_t c_cflag;               /* control mode flags */
+       tcflag_t c_lflag;               /* local mode flags */
+       cc_t c_cc[NCCS];                /* control characters */
+       cc_t c_line;                    /* line discipline (== c_cc[19]) */
+       speed_t c_ispeed;               /* input speed */
+       speed_t c_ospeed;               /* output speed */
+};
+
 /* Alpha has matching termios and ktermios */
 
 struct ktermios {
@@ -147,6 +160,7 @@ struct ktermios {
 #define B3000000  00034
 #define B3500000  00035
 #define B4000000  00036
+#define BOTHER    00037
 
 #define CSIZE  00001400
 #define   CS5  00000000
@@ -164,6 +178,9 @@ struct ktermios {
 #define CMSPAR   010000000000          /* mark or space (stick) parity */
 #define CRTSCTS          020000000000          /* flow control */
 
+#define CIBAUD 07600000
+#define IBSHIFT        16
+
 /* c_lflag bits */
 #define ISIG   0x00000080
 #define ICANON 0x00000100