Merge branch 'mpi-master' into wip-k-fmlpwip-k-fmlp

Conflicts:
	litmus/sched_cedf.c

1 files changed, 1181 insertions, 0 deletions

diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c
new file mode 100644
index 000000000000..53f2442c6099
--- /dev/null
+++ b/drivers/tty/tty_ioctl.c
@@ -0,0 +1,1181 @@
+/*
+ *  Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
+ *
+ * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines
+ * which can be dynamically activated and de-activated by the line
+ * discipline handling modules (like SLIP).
+ */
+
+#include <linux/types.h>
+#include <linux/termios.h>
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/tty.h>
+#include <linux/fcntl.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/bitops.h>
+#include <linux/mutex.h>
+
+#include <asm/io.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+
+#undef TTY_DEBUG_WAIT_UNTIL_SENT
+
+#undef  DEBUG
+
+/*
+ * Internal flag options for termios setting behavior
+ */
+#define TERMIOS_FLUSH   1
+#define TERMIOS_WAIT    2
+#define TERMIOS_TERMIO  4
+#define TERMIOS_OLD     8
+
+
+/**
+ *      tty_chars_in_buffer     -       characters pending
+ *      @tty: terminal
+ *
+ *      Return the number of bytes of data in the device private
+ *      output queue. If no private method is supplied there is assumed
+ *      to be no queue on the device.
+ */
+
+int tty_chars_in_buffer(struct tty_struct *tty)
+{
+        if (tty->ops->chars_in_buffer)
+                return tty->ops->chars_in_buffer(tty);
+        else
+                return 0;
+}
+EXPORT_SYMBOL(tty_chars_in_buffer);
+
+/**
+ *      tty_write_room          -       write queue space
+ *      @tty: terminal
+ *
+ *      Return the number of bytes that can be queued to this device
+ *      at the present time. The result should be treated as a guarantee
+ *      and the driver cannot offer a value it later shrinks by more than
+ *      the number of bytes written. If no method is provided 2K is always
+ *      returned and data may be lost as there will be no flow control.
+ */
+ 
+int tty_write_room(struct tty_struct *tty)
+{
+        if (tty->ops->write_room)
+                return tty->ops->write_room(tty);
+        return 2048;
+}
+EXPORT_SYMBOL(tty_write_room);
+
+/**
+ *      tty_driver_flush_buffer -       discard internal buffer
+ *      @tty: terminal
+ *
+ *      Discard the internal output buffer for this device. If no method
+ *      is provided then either the buffer cannot be hardware flushed or
+ *      there is no buffer driver side.
+ */
+void tty_driver_flush_buffer(struct tty_struct *tty)
+{
+        if (tty->ops->flush_buffer)
+                tty->ops->flush_buffer(tty);
+}
+EXPORT_SYMBOL(tty_driver_flush_buffer);
+
+/**
+ *      tty_throttle            -       flow control
+ *      @tty: terminal
+ *
+ *      Indicate that a tty should stop transmitting data down the stack.
+ *      Takes the termios mutex to protect against parallel throttle/unthrottle
+ *      and also to ensure the driver can consistently reference its own
+ *      termios data at this point when implementing software flow control.
+ */
+
+void tty_throttle(struct tty_struct *tty)
+{
+        mutex_lock(&tty->termios_mutex);
+        /* check TTY_THROTTLED first so it indicates our state */
+        if (!test_and_set_bit(TTY_THROTTLED, &tty->flags) &&
+            tty->ops->throttle)
+                tty->ops->throttle(tty);
+        mutex_unlock(&tty->termios_mutex);
+}
+EXPORT_SYMBOL(tty_throttle);
+
+/**
+ *      tty_unthrottle          -       flow control
+ *      @tty: terminal
+ *
+ *      Indicate that a tty may continue transmitting data down the stack.
+ *      Takes the termios mutex to protect against parallel throttle/unthrottle
+ *      and also to ensure the driver can consistently reference its own
+ *      termios data at this point when implementing software flow control.
+ *
+ *      Drivers should however remember that the stack can issue a throttle,
+ *      then change flow control method, then unthrottle.
+ */
+
+void tty_unthrottle(struct tty_struct *tty)
+{
+        mutex_lock(&tty->termios_mutex);
+        if (test_and_clear_bit(TTY_THROTTLED, &tty->flags) &&
+            tty->ops->unthrottle)
+                tty->ops->unthrottle(tty);
+        mutex_unlock(&tty->termios_mutex);
+}
+EXPORT_SYMBOL(tty_unthrottle);
+
+/**
+ *      tty_wait_until_sent     -       wait for I/O to finish
+ *      @tty: tty we are waiting for
+ *      @timeout: how long we will wait
+ *
+ *      Wait for characters pending in a tty driver to hit the wire, or
+ *      for a timeout to occur (eg due to flow control)
+ *
+ *      Locking: none
+ */
+
+void tty_wait_until_sent(struct tty_struct *tty, long timeout)
+{
+#ifdef TTY_DEBUG_WAIT_UNTIL_SENT
+        char buf[64];
+
+        printk(KERN_DEBUG "%s wait until sent...\n", tty_name(tty, buf));
+#endif
+        if (!timeout)
+                timeout = MAX_SCHEDULE_TIMEOUT;
+        if (wait_event_interruptible_timeout(tty->write_wait,
+                        !tty_chars_in_buffer(tty), timeout) >= 0) {
+                if (tty->ops->wait_until_sent)
+                        tty->ops->wait_until_sent(tty, timeout);
+        }
+}
+EXPORT_SYMBOL(tty_wait_until_sent);
+
+
+/*
+ *              Termios Helper Methods
+ */
+
+static void unset_locked_termios(struct ktermios *termios,
+                                 struct ktermios *old,
+                                 struct ktermios *locked)
+{
+        int     i;
+
+#define NOSET_MASK(x, y, z) (x = ((x) & ~(z)) | ((y) & (z)))
+
+        if (!locked) {
+                printk(KERN_WARNING "Warning?!? termios_locked is NULL.\n");
+                return;
+        }
+
+        NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag);
+        NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag);
+        NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag);
+        NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag);
+        termios->c_line = locked->c_line ? old->c_line : termios->c_line;
+        for (i = 0; i < NCCS; i++)
+                termios->c_cc[i] = locked->c_cc[i] ?
+                        old->c_cc[i] : termios->c_cc[i];
+        /* FIXME: What should we do for i/ospeed */
+}
+
+/*
+ * Routine which returns the baud rate of the tty
+ *
+ * Note that the baud_table needs to be kept in sync with the
+ * include/asm/termbits.h file.
+ */
+static const speed_t baud_table[] = {
+        0, 50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800,
+        9600, 19200, 38400, 57600, 115200, 230400, 460800,
+#ifdef __sparc__
+        76800, 153600, 307200, 614400, 921600
+#else
+        500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000,
+        2500000, 3000000, 3500000, 4000000
+#endif
+};
+
+#ifndef __sparc__
+static const tcflag_t baud_bits[] = {
+        B0, B50, B75, B110, B134, B150, B200, B300, B600,
+        B1200, B1800, B2400, B4800, B9600, B19200, B38400,
+        B57600, B115200, B230400, B460800, B500000, B576000,
+        B921600, B1000000, B1152000, B1500000, B2000000, B2500000,
+        B3000000, B3500000, B4000000
+};
+#else
+static const tcflag_t baud_bits[] = {
+        B0, B50, B75, B110, B134, B150, B200, B300, B600,
+        B1200, B1800, B2400, B4800, B9600, B19200, B38400,
+        B57600, B115200, B230400, B460800, B76800, B153600,
+        B307200, B614400, B921600
+};
+#endif
+
+static int n_baud_table = ARRAY_SIZE(baud_table);
+
+/**
+ *      tty_termios_baud_rate
+ *      @termios: termios structure
+ *
+ *      Convert termios baud rate data into a speed. This should be called
+ *      with the termios lock held if this termios is a terminal termios
+ *      structure. May change the termios data. Device drivers can call this
+ *      function but should use ->c_[io]speed directly as they are updated.
+ *
+ *      Locking: none
+ */
+
+speed_t tty_termios_baud_rate(struct ktermios *termios)
+{
+        unsigned int cbaud;
+
+        cbaud = termios->c_cflag & CBAUD;
+
+#ifdef BOTHER
+        /* Magic token for arbitrary speed via c_ispeed/c_ospeed */
+        if (cbaud == BOTHER)
+                return termios->c_ospeed;
+#endif
+        if (cbaud & CBAUDEX) {
+                cbaud &= ~CBAUDEX;
+
+                if (cbaud < 1 || cbaud + 15 > n_baud_table)
+                        termios->c_cflag &= ~CBAUDEX;
+                else
+                        cbaud += 15;
+        }
+        return baud_table[cbaud];
+}
+EXPORT_SYMBOL(tty_termios_baud_rate);
+
+/**
+ *      tty_termios_input_baud_rate
+ *      @termios: termios structure
+ *
+ *      Convert termios baud rate data into a speed. This should be called
+ *      with the termios lock held if this termios is a terminal termios
+ *      structure. May change the termios data. Device drivers can call this
+ *      function but should use ->c_[io]speed directly as they are updated.
+ *
+ *      Locking: none
+ */
+
+speed_t tty_termios_input_baud_rate(struct ktermios *termios)
+{
+#ifdef IBSHIFT
+        unsigned int cbaud = (termios->c_cflag >> IBSHIFT) & CBAUD;
+
+        if (cbaud == B0)
+                return tty_termios_baud_rate(termios);
+
+        /* Magic token for arbitrary speed via c_ispeed*/
+        if (cbaud == BOTHER)
+                return termios->c_ispeed;
+
+        if (cbaud & CBAUDEX) {
+                cbaud &= ~CBAUDEX;
+
+                if (cbaud < 1 || cbaud + 15 > n_baud_table)
+                        termios->c_cflag &= ~(CBAUDEX << IBSHIFT);
+                else
+                        cbaud += 15;
+        }
+        return baud_table[cbaud];
+#else
+        return tty_termios_baud_rate(termios);
+#endif
+}
+EXPORT_SYMBOL(tty_termios_input_baud_rate);
+
+/**
+ *      tty_termios_encode_baud_rate
+ *      @termios: ktermios structure holding user requested state
+ *      @ispeed: input speed
+ *      @ospeed: output speed
+ *
+ *      Encode the speeds set into the passed termios structure. This is
+ *      used as a library helper for drivers so that they can report back
+ *      the actual speed selected when it differs from the speed requested
+ *
+ *      For maximal back compatibility with legacy SYS5/POSIX *nix behaviour
+ *      we need to carefully set the bits when the user does not get the
+ *      desired speed. We allow small margins and preserve as much of possible
+ *      of the input intent to keep compatibility.
+ *
+ *      Locking: Caller should hold termios lock. This is already held
+ *      when calling this function from the driver termios handler.
+ *
+ *      The ifdefs deal with platforms whose owners have yet to update them
+ *      and will all go away once this is done.
+ */
+
+void tty_termios_encode_baud_rate(struct ktermios *termios,
+                                  speed_t ibaud, speed_t obaud)
+{
+        int i = 0;
+        int ifound = -1, ofound = -1;
+        int iclose = ibaud/50, oclose = obaud/50;
+        int ibinput = 0;
+
+        if (obaud == 0)                 /* CD dropped             */
+                ibaud = 0;              /* Clear ibaud to be sure */
+
+        termios->c_ispeed = ibaud;
+        termios->c_ospeed = obaud;
+
+#ifdef BOTHER
+        /* If the user asked for a precise weird speed give a precise weird
+           answer. If they asked for a Bfoo speed they many have problems
+           digesting non-exact replies so fuzz a bit */
+
+        if ((termios->c_cflag & CBAUD) == BOTHER)
+                oclose = 0;
+        if (((termios->c_cflag >> IBSHIFT) & CBAUD) == BOTHER)
+                iclose = 0;
+        if ((termios->c_cflag >> IBSHIFT) & CBAUD)
+                ibinput = 1;    /* An input speed was specified */
+#endif
+        termios->c_cflag &= ~CBAUD;
+
+        /*
+         *      Our goal is to find a close match to the standard baud rate
+         *      returned. Walk the baud rate table and if we get a very close
+         *      match then report back the speed as a POSIX Bxxxx value by
+         *      preference
+         */
+
+        do {
+                if (obaud - oclose <= baud_table[i] &&
+                    obaud + oclose >= baud_table[i]) {
+                        termios->c_cflag |= baud_bits[i];
+                        ofound = i;
+                }
+                if (ibaud - iclose <= baud_table[i] &&
+                    ibaud + iclose >= baud_table[i]) {
+                        /* For the case input == output don't set IBAUD bits
+                           if the user didn't do so */
+                        if (ofound == i && !ibinput)
+                                ifound  = i;
+#ifdef IBSHIFT
+                        else {
+                                ifound = i;
+                                termios->c_cflag |= (baud_bits[i] << IBSHIFT);
+                        }
+#endif
+                }
+        } while (++i < n_baud_table);
+
+        /*
+         *      If we found no match then use BOTHER if provided or warn
+         *      the user their platform maintainer needs to wake up if not.
+         */
+#ifdef BOTHER
+        if (ofound == -1)
+                termios->c_cflag |= BOTHER;
+        /* Set exact input bits only if the input and output differ or the
+           user already did */
+        if (ifound == -1 && (ibaud != obaud || ibinput))
+                termios->c_cflag |= (BOTHER << IBSHIFT);
+#else
+        if (ifound == -1 || ofound == -1) {
+                printk_once(KERN_WARNING "tty: Unable to return correct "
+                          "speed data as your architecture needs updating.\n");
+        }
+#endif
+}
+EXPORT_SYMBOL_GPL(tty_termios_encode_baud_rate);
+
+/**
+ *      tty_encode_baud_rate            -       set baud rate of the tty
+ *      @ibaud: input baud rate
+ *      @obad: output baud rate
+ *
+ *      Update the current termios data for the tty with the new speed
+ *      settings. The caller must hold the termios_mutex for the tty in
+ *      question.
+ */
+
+void tty_encode_baud_rate(struct tty_struct *tty, speed_t ibaud, speed_t obaud)
+{
+        tty_termios_encode_baud_rate(tty->termios, ibaud, obaud);
+}
+EXPORT_SYMBOL_GPL(tty_encode_baud_rate);
+
+/**
+ *      tty_get_baud_rate       -       get tty bit rates
+ *      @tty: tty to query
+ *
+ *      Returns the baud rate as an integer for this terminal. The
+ *      termios lock must be held by the caller and the terminal bit
+ *      flags may be updated.
+ *
+ *      Locking: none
+ */
+
+speed_t tty_get_baud_rate(struct tty_struct *tty)
+{
+        speed_t baud = tty_termios_baud_rate(tty->termios);
+
+        if (baud == 38400 && tty->alt_speed) {
+                if (!tty->warned) {
+                        printk(KERN_WARNING "Use of setserial/setrocket to "
+                                            "set SPD_* flags is deprecated\n");
+                        tty->warned = 1;
+                }
+                baud = tty->alt_speed;
+        }
+
+        return baud;
+}
+EXPORT_SYMBOL(tty_get_baud_rate);
+
+/**
+ *      tty_termios_copy_hw     -       copy hardware settings
+ *      @new: New termios
+ *      @old: Old termios
+ *
+ *      Propagate the hardware specific terminal setting bits from
+ *      the old termios structure to the new one. This is used in cases
+ *      where the hardware does not support reconfiguration or as a helper
+ *      in some cases where only minimal reconfiguration is supported
+ */
+
+void tty_termios_copy_hw(struct ktermios *new, struct ktermios *old)
+{
+        /* The bits a dumb device handles in software. Smart devices need
+           to always provide a set_termios method */
+        new->c_cflag &= HUPCL | CREAD | CLOCAL;
+        new->c_cflag |= old->c_cflag & ~(HUPCL | CREAD | CLOCAL);
+        new->c_ispeed = old->c_ispeed;
+        new->c_ospeed = old->c_ospeed;
+}
+EXPORT_SYMBOL(tty_termios_copy_hw);
+
+/**
+ *      tty_termios_hw_change   -       check for setting change
+ *      @a: termios
+ *      @b: termios to compare
+ *
+ *      Check if any of the bits that affect a dumb device have changed
+ *      between the two termios structures, or a speed change is needed.
+ */
+
+int tty_termios_hw_change(struct ktermios *a, struct ktermios *b)
+{
+        if (a->c_ispeed != b->c_ispeed || a->c_ospeed != b->c_ospeed)
+                return 1;
+        if ((a->c_cflag ^ b->c_cflag) & ~(HUPCL | CREAD | CLOCAL))
+                return 1;
+        return 0;
+}
+EXPORT_SYMBOL(tty_termios_hw_change);
+
+/**
+ *      tty_set_termios         -       update termios values
+ *      @tty: tty to update
+ *      @new_termios: desired new value
+ *
+ *      Perform updates to the termios values set on this terminal. There
+ *      is a bit of layering violation here with n_tty in terms of the
+ *      internal knowledge of this function.
+ *
+ *      Locking: termios_mutex
+ */
+
+int tty_set_termios(struct tty_struct *tty, struct ktermios *new_termios)
+{
+        struct ktermios old_termios;
+        struct tty_ldisc *ld;
+        unsigned long flags;
+
+        /*
+         *      Perform the actual termios internal changes under lock.
+         */
+
+
+        /* FIXME: we need to decide on some locking/ordering semantics
+           for the set_termios notification eventually */
+        mutex_lock(&tty->termios_mutex);
+        old_termios = *tty->termios;
+        *tty->termios = *new_termios;
+        unset_locked_termios(tty->termios, &old_termios, tty->termios_locked);
+
+        /* 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) || extproc) {
+                        spin_lock_irqsave(&tty->ctrl_lock, flags);
+                        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);
+                }
+        }
+
+        if (tty->ops->set_termios)
+                (*tty->ops->set_termios)(tty, &old_termios);
+        else
+                tty_termios_copy_hw(tty->termios, &old_termios);
+
+        ld = tty_ldisc_ref(tty);
+        if (ld != NULL) {
+                if (ld->ops->set_termios)
+                        (ld->ops->set_termios)(tty, &old_termios);
+                tty_ldisc_deref(ld);
+        }
+        mutex_unlock(&tty->termios_mutex);
+        return 0;
+}
+EXPORT_SYMBOL_GPL(tty_set_termios);
+
+/**
+ *      set_termios             -       set termios values for a tty
+ *      @tty: terminal device
+ *      @arg: user data
+ *      @opt: option information
+ *
+ *      Helper function to prepare termios data and run necessary other
+ *      functions before using tty_set_termios to do the actual changes.
+ *
+ *      Locking:
+ *              Called functions take ldisc and termios_mutex locks
+ */
+
+static int set_termios(struct tty_struct *tty, void __user *arg, int opt)
+{
+        struct ktermios tmp_termios;
+        struct tty_ldisc *ld;
+        int retval = tty_check_change(tty);
+
+        if (retval)
+                return retval;
+
+        mutex_lock(&tty->termios_mutex);
+        memcpy(&tmp_termios, tty->termios, sizeof(struct ktermios));
+        mutex_unlock(&tty->termios_mutex);
+
+        if (opt & TERMIOS_TERMIO) {
+                if (user_termio_to_kernel_termios(&tmp_termios,
+                                                (struct termio __user *)arg))
+                        return -EFAULT;
+#ifdef TCGETS2
+        } else if (opt & TERMIOS_OLD) {
+                if (user_termios_to_kernel_termios_1(&tmp_termios,
+                                                (struct termios __user *)arg))
+                        return -EFAULT;
+        } else {
+                if (user_termios_to_kernel_termios(&tmp_termios,
+                                                (struct termios2 __user *)arg))
+                        return -EFAULT;
+        }
+#else
+        } else if (user_termios_to_kernel_termios(&tmp_termios,
+                                        (struct termios __user *)arg))
+                return -EFAULT;
+#endif
+
+        /* If old style Bfoo values are used then load c_ispeed/c_ospeed
+         * with the real speed so its unconditionally usable */
+        tmp_termios.c_ispeed = tty_termios_input_baud_rate(&tmp_termios);
+        tmp_termios.c_ospeed = tty_termios_baud_rate(&tmp_termios);
+
+        ld = tty_ldisc_ref(tty);
+
+        if (ld != NULL) {
+                if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
+                        ld->ops->flush_buffer(tty);
+                tty_ldisc_deref(ld);
+        }
+
+        if (opt & TERMIOS_WAIT) {
+                tty_wait_until_sent(tty, 0);
+                if (signal_pending(current))
+                        return -EINTR;
+        }
+
+        tty_set_termios(tty, &tmp_termios);
+
+        /* FIXME: Arguably if tmp_termios == tty->termios AND the
+           actual requested termios was not tmp_termios then we may
+           want to return an error as no user requested change has
+           succeeded */
+        return 0;
+}
+
+static void copy_termios(struct tty_struct *tty, struct ktermios *kterm)
+{
+        mutex_lock(&tty->termios_mutex);
+        memcpy(kterm, tty->termios, sizeof(struct ktermios));
+        mutex_unlock(&tty->termios_mutex);
+}
+
+static void copy_termios_locked(struct tty_struct *tty, struct ktermios *kterm)
+{
+        mutex_lock(&tty->termios_mutex);
+        memcpy(kterm, tty->termios_locked, sizeof(struct ktermios));
+        mutex_unlock(&tty->termios_mutex);
+}
+
+static int get_termio(struct tty_struct *tty, struct termio __user *termio)
+{
+        struct ktermios kterm;
+        copy_termios(tty, &kterm);
+        if (kernel_termios_to_user_termio(termio, &kterm))
+                return -EFAULT;
+        return 0;
+}
+
+
+#ifdef TCGETX
+
+/**
+ *      set_termiox     -       set termiox fields if possible
+ *      @tty: terminal
+ *      @arg: termiox structure from user
+ *      @opt: option flags for ioctl type
+ *
+ *      Implement the device calling points for the SYS5 termiox ioctl
+ *      interface in Linux
+ */
+
+static int set_termiox(struct tty_struct *tty, void __user *arg, int opt)
+{
+        struct termiox tnew;
+        struct tty_ldisc *ld;
+
+        if (tty->termiox == NULL)
+                return -EINVAL;
+        if (copy_from_user(&tnew, arg, sizeof(struct termiox)))
+                return -EFAULT;
+
+        ld = tty_ldisc_ref(tty);
+        if (ld != NULL) {
+                if ((opt & TERMIOS_FLUSH) && ld->ops->flush_buffer)
+                        ld->ops->flush_buffer(tty);
+                tty_ldisc_deref(ld);
+        }
+        if (opt & TERMIOS_WAIT) {
+                tty_wait_until_sent(tty, 0);
+                if (signal_pending(current))
+                        return -EINTR;
+        }
+
+        mutex_lock(&tty->termios_mutex);
+        if (tty->ops->set_termiox)
+                tty->ops->set_termiox(tty, &tnew);
+        mutex_unlock(&tty->termios_mutex);
+        return 0;
+}
+
+#endif
+
+
+#ifdef TIOCGETP
+/*
+ * These are deprecated, but there is limited support..
+ *
+ * The "sg_flags" translation is a joke..
+ */
+static int get_sgflags(struct tty_struct *tty)
+{
+        int flags = 0;
+
+        if (!(tty->termios->c_lflag & ICANON)) {
+                if (tty->termios->c_lflag & ISIG)
+                        flags |= 0x02;          /* cbreak */
+                else
+                        flags |= 0x20;          /* raw */
+        }
+        if (tty->termios->c_lflag & ECHO)
+                flags |= 0x08;                  /* echo */
+        if (tty->termios->c_oflag & OPOST)
+                if (tty->termios->c_oflag & ONLCR)
+                        flags |= 0x10;          /* crmod */
+        return flags;
+}
+
+static int get_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
+{
+        struct sgttyb tmp;
+
+        mutex_lock(&tty->termios_mutex);
+        tmp.sg_ispeed = tty->termios->c_ispeed;
+        tmp.sg_ospeed = tty->termios->c_ospeed;
+        tmp.sg_erase = tty->termios->c_cc[VERASE];
+        tmp.sg_kill = tty->termios->c_cc[VKILL];
+        tmp.sg_flags = get_sgflags(tty);
+        mutex_unlock(&tty->termios_mutex);
+
+        return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0;
+}
+
+static void set_sgflags(struct ktermios *termios, int flags)
+{
+        termios->c_iflag = ICRNL | IXON;
+        termios->c_oflag = 0;
+        termios->c_lflag = ISIG | ICANON;
+        if (flags & 0x02) {     /* cbreak */
+                termios->c_iflag = 0;
+                termios->c_lflag &= ~ICANON;
+        }
+        if (flags & 0x08) {             /* echo */
+                termios->c_lflag |= ECHO | ECHOE | ECHOK |
+                                    ECHOCTL | ECHOKE | IEXTEN;
+        }
+        if (flags & 0x10) {             /* crmod */
+                termios->c_oflag |= OPOST | ONLCR;
+        }
+        if (flags & 0x20) {     /* raw */
+                termios->c_iflag = 0;
+                termios->c_lflag &= ~(ISIG | ICANON);
+        }
+        if (!(termios->c_lflag & ICANON)) {
+                termios->c_cc[VMIN] = 1;
+                termios->c_cc[VTIME] = 0;
+        }
+}
+
+/**
+ *      set_sgttyb              -       set legacy terminal values
+ *      @tty: tty structure
+ *      @sgttyb: pointer to old style terminal structure
+ *
+ *      Updates a terminal from the legacy BSD style terminal information
+ *      structure.
+ *
+ *      Locking: termios_mutex
+ */
+
+static int set_sgttyb(struct tty_struct *tty, struct sgttyb __user *sgttyb)
+{
+        int retval;
+        struct sgttyb tmp;
+        struct ktermios termios;
+
+        retval = tty_check_change(tty);
+        if (retval)
+                return retval;
+
+        if (copy_from_user(&tmp, sgttyb, sizeof(tmp)))
+                return -EFAULT;
+
+        mutex_lock(&tty->termios_mutex);
+        termios = *tty->termios;
+        termios.c_cc[VERASE] = tmp.sg_erase;
+        termios.c_cc[VKILL] = tmp.sg_kill;
+        set_sgflags(&termios, tmp.sg_flags);
+        /* Try and encode into Bfoo format */
+#ifdef BOTHER
+        tty_termios_encode_baud_rate(&termios, termios.c_ispeed,
+                                                termios.c_ospeed);
+#endif
+        mutex_unlock(&tty->termios_mutex);
+        tty_set_termios(tty, &termios);
+        return 0;
+}
+#endif
+
+#ifdef TIOCGETC
+static int get_tchars(struct tty_struct *tty, struct tchars __user *tchars)
+{
+        struct tchars tmp;
+
+        mutex_lock(&tty->termios_mutex);
+        tmp.t_intrc = tty->termios->c_cc[VINTR];
+        tmp.t_quitc = tty->termios->c_cc[VQUIT];
+        tmp.t_startc = tty->termios->c_cc[VSTART];
+        tmp.t_stopc = tty->termios->c_cc[VSTOP];
+        tmp.t_eofc = tty->termios->c_cc[VEOF];
+        tmp.t_brkc = tty->termios->c_cc[VEOL2]; /* what is brkc anyway? */
+        mutex_unlock(&tty->termios_mutex);
+        return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
+}
+
+static int set_tchars(struct tty_struct *tty, struct tchars __user *tchars)
+{
+        struct tchars tmp;
+
+        if (copy_from_user(&tmp, tchars, sizeof(tmp)))
+                return -EFAULT;
+        mutex_lock(&tty->termios_mutex);
+        tty->termios->c_cc[VINTR] = tmp.t_intrc;
+        tty->termios->c_cc[VQUIT] = tmp.t_quitc;
+        tty->termios->c_cc[VSTART] = tmp.t_startc;
+        tty->termios->c_cc[VSTOP] = tmp.t_stopc;
+        tty->termios->c_cc[VEOF] = tmp.t_eofc;
+        tty->termios->c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */
+        mutex_unlock(&tty->termios_mutex);
+        return 0;
+}
+#endif
+
+#ifdef TIOCGLTC
+static int get_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
+{
+        struct ltchars tmp;
+
+        mutex_lock(&tty->termios_mutex);
+        tmp.t_suspc = tty->termios->c_cc[VSUSP];
+        /* what is dsuspc anyway? */
+        tmp.t_dsuspc = tty->termios->c_cc[VSUSP];
+        tmp.t_rprntc = tty->termios->c_cc[VREPRINT];
+        /* what is flushc anyway? */
+        tmp.t_flushc = tty->termios->c_cc[VEOL2];
+        tmp.t_werasc = tty->termios->c_cc[VWERASE];
+        tmp.t_lnextc = tty->termios->c_cc[VLNEXT];
+        mutex_unlock(&tty->termios_mutex);
+        return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
+}
+
+static int set_ltchars(struct tty_struct *tty, struct ltchars __user *ltchars)
+{
+        struct ltchars tmp;
+
+        if (copy_from_user(&tmp, ltchars, sizeof(tmp)))
+                return -EFAULT;
+
+        mutex_lock(&tty->termios_mutex);
+        tty->termios->c_cc[VSUSP] = tmp.t_suspc;
+        /* what is dsuspc anyway? */
+        tty->termios->c_cc[VEOL2] = tmp.t_dsuspc;
+        tty->termios->c_cc[VREPRINT] = tmp.t_rprntc;
+        /* what is flushc anyway? */
+        tty->termios->c_cc[VEOL2] = tmp.t_flushc;
+        tty->termios->c_cc[VWERASE] = tmp.t_werasc;
+        tty->termios->c_cc[VLNEXT] = tmp.t_lnextc;
+        mutex_unlock(&tty->termios_mutex);
+        return 0;
+}
+#endif
+
+/**
+ *      send_prio_char          -       send priority character
+ *
+ *      Send a high priority character to the tty even if stopped
+ *
+ *      Locking: none for xchar method, write ordering for write method.
+ */
+
+static int send_prio_char(struct tty_struct *tty, char ch)
+{
+        int     was_stopped = tty->stopped;
+
+        if (tty->ops->send_xchar) {
+                tty->ops->send_xchar(tty, ch);
+                return 0;
+        }
+
+        if (tty_write_lock(tty, 0) < 0)
+                return -ERESTARTSYS;
+
+        if (was_stopped)
+                start_tty(tty);
+        tty->ops->write(tty, &ch, 1);
+        if (was_stopped)
+                stop_tty(tty);
+        tty_write_unlock(tty);
+        return 0;
+}
+
+/**
+ *      tty_change_softcar      -       carrier change ioctl helper
+ *      @tty: tty to update
+ *      @arg: enable/disable CLOCAL
+ *
+ *      Perform a change to the CLOCAL state and call into the driver
+ *      layer to make it visible. All done with the termios mutex
+ */
+
+static int tty_change_softcar(struct tty_struct *tty, int arg)
+{
+        int ret = 0;
+        int bit = arg ? CLOCAL : 0;
+        struct ktermios old;
+
+        mutex_lock(&tty->termios_mutex);
+        old = *tty->termios;
+        tty->termios->c_cflag &= ~CLOCAL;
+        tty->termios->c_cflag |= bit;
+        if (tty->ops->set_termios)
+                tty->ops->set_termios(tty, &old);
+        if ((tty->termios->c_cflag & CLOCAL) != bit)
+                ret = -EINVAL;
+        mutex_unlock(&tty->termios_mutex);
+        return ret;
+}
+
+/**
+ *      tty_mode_ioctl          -       mode related ioctls
+ *      @tty: tty for the ioctl
+ *      @file: file pointer for the tty
+ *      @cmd: command
+ *      @arg: ioctl argument
+ *
+ *      Perform non line discipline specific mode control ioctls. This
+ *      is designed to be called by line disciplines to ensure they provide
+ *      consistent mode setting.
+ */
+
+int tty_mode_ioctl(struct tty_struct *tty, struct file *file,
+                        unsigned int cmd, unsigned long arg)
+{
+        struct tty_struct *real_tty;
+        void __user *p = (void __user *)arg;
+        int ret = 0;
+        struct ktermios kterm;
+
+        BUG_ON(file == NULL);
+
+        if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
+            tty->driver->subtype == PTY_TYPE_MASTER)
+                real_tty = tty->link;
+        else
+                real_tty = tty;
+
+        switch (cmd) {
+#ifdef TIOCGETP
+        case TIOCGETP:
+                return get_sgttyb(real_tty, (struct sgttyb __user *) arg);
+        case TIOCSETP:
+        case TIOCSETN:
+                return set_sgttyb(real_tty, (struct sgttyb __user *) arg);
+#endif
+#ifdef TIOCGETC
+        case TIOCGETC:
+                return get_tchars(real_tty, p);
+        case TIOCSETC:
+                return set_tchars(real_tty, p);
+#endif
+#ifdef TIOCGLTC
+        case TIOCGLTC:
+                return get_ltchars(real_tty, p);
+        case TIOCSLTC:
+                return set_ltchars(real_tty, p);
+#endif
+        case TCSETSF:
+                return set_termios(real_tty, p,  TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_OLD);
+        case TCSETSW:
+                return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_OLD);
+        case TCSETS:
+                return set_termios(real_tty, p, TERMIOS_OLD);
+#ifndef TCGETS2
+        case TCGETS:
+                copy_termios(real_tty, &kterm);
+                if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm))
+                        ret = -EFAULT;
+                return ret;
+#else
+        case TCGETS:
+                copy_termios(real_tty, &kterm);
+                if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm))
+                        ret = -EFAULT;
+                return ret;
+        case TCGETS2:
+                copy_termios(real_tty, &kterm);
+                if (kernel_termios_to_user_termios((struct termios2 __user *)arg, &kterm))
+                        ret = -EFAULT;
+                return ret;
+        case TCSETSF2:
+                return set_termios(real_tty, p,  TERMIOS_FLUSH | TERMIOS_WAIT);
+        case TCSETSW2:
+                return set_termios(real_tty, p, TERMIOS_WAIT);
+        case TCSETS2:
+                return set_termios(real_tty, p, 0);
+#endif
+        case TCGETA:
+                return get_termio(real_tty, p);
+        case TCSETAF:
+                return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO);
+        case TCSETAW:
+                return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO);
+        case TCSETA:
+                return set_termios(real_tty, p, TERMIOS_TERMIO);
+#ifndef TCGETS2
+        case TIOCGLCKTRMIOS:
+                copy_termios_locked(real_tty, &kterm);
+                if (kernel_termios_to_user_termios((struct termios __user *)arg, &kterm))
+                        ret = -EFAULT;
+                return ret;
+        case TIOCSLCKTRMIOS:
+                if (!capable(CAP_SYS_ADMIN))
+                        return -EPERM;
+                copy_termios_locked(real_tty, &kterm);
+                if (user_termios_to_kernel_termios(&kterm,
+                                               (struct termios __user *) arg))
+                        return -EFAULT;
+                mutex_lock(&real_tty->termios_mutex);
+                memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios));
+                mutex_unlock(&real_tty->termios_mutex);
+                return 0;
+#else
+        case TIOCGLCKTRMIOS:
+                copy_termios_locked(real_tty, &kterm);
+                if (kernel_termios_to_user_termios_1((struct termios __user *)arg, &kterm))
+                        ret = -EFAULT;
+                return ret;
+        case TIOCSLCKTRMIOS:
+                if (!capable(CAP_SYS_ADMIN))
+                        return -EPERM;
+                copy_termios_locked(real_tty, &kterm);
+                if (user_termios_to_kernel_termios_1(&kterm,
+                                               (struct termios __user *) arg))
+                        return -EFAULT;
+                mutex_lock(&real_tty->termios_mutex);
+                memcpy(real_tty->termios_locked, &kterm, sizeof(struct ktermios));
+                mutex_unlock(&real_tty->termios_mutex);
+                return ret;
+#endif
+#ifdef TCGETX
+        case TCGETX: {
+                struct termiox ktermx;
+                if (real_tty->termiox == NULL)
+                        return -EINVAL;
+                mutex_lock(&real_tty->termios_mutex);
+                memcpy(&ktermx, real_tty->termiox, sizeof(struct termiox));
+                mutex_unlock(&real_tty->termios_mutex);
+                if (copy_to_user(p, &ktermx, sizeof(struct termiox)))
+                        ret = -EFAULT;
+                return ret;
+        }
+        case TCSETX:
+                return set_termiox(real_tty, p, 0);
+        case TCSETXW:
+                return set_termiox(real_tty, p, TERMIOS_WAIT);
+        case TCSETXF:
+                return set_termiox(real_tty, p, TERMIOS_FLUSH);
+#endif          
+        case TIOCGSOFTCAR:
+                copy_termios(real_tty, &kterm);
+                ret = put_user((kterm.c_cflag & CLOCAL) ? 1 : 0,
+                                                (int __user *)arg);
+                return ret;
+        case TIOCSSOFTCAR:
+                if (get_user(arg, (unsigned int __user *) arg))
+                        return -EFAULT;
+                return tty_change_softcar(real_tty, arg);
+        default:
+                return -ENOIOCTLCMD;
+        }
+}
+EXPORT_SYMBOL_GPL(tty_mode_ioctl);
+
+int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
+{
+        struct tty_ldisc *ld;
+        int retval = tty_check_change(tty);
+        if (retval)
+                return retval;
+
+        ld = tty_ldisc_ref_wait(tty);
+        switch (arg) {
+        case TCIFLUSH:
+                if (ld && ld->ops->flush_buffer)
+                        ld->ops->flush_buffer(tty);
+                break;
+        case TCIOFLUSH:
+                if (ld && ld->ops->flush_buffer)
+                        ld->ops->flush_buffer(tty);
+                /* fall through */
+        case TCOFLUSH:
+                tty_driver_flush_buffer(tty);
+                break;
+        default:
+                tty_ldisc_deref(ld);
+                return -EINVAL;
+        }
+        tty_ldisc_deref(ld);
+        return 0;
+}
+EXPORT_SYMBOL_GPL(tty_perform_flush);
+
+int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
+                       unsigned int cmd, unsigned long arg)
+{
+        unsigned long flags;
+        int retval;
+
+        switch (cmd) {
+        case TCXONC:
+                retval = tty_check_change(tty);
+                if (retval)
+                        return retval;
+                switch (arg) {
+                case TCOOFF:
+                        if (!tty->flow_stopped) {
+                                tty->flow_stopped = 1;
+                                stop_tty(tty);
+                        }
+                        break;
+                case TCOON:
+                        if (tty->flow_stopped) {
+                                tty->flow_stopped = 0;
+                                start_tty(tty);
+                        }
+                        break;
+                case TCIOFF:
+                        if (STOP_CHAR(tty) != __DISABLED_CHAR)
+                                return send_prio_char(tty, STOP_CHAR(tty));
+                        break;
+                case TCION:
+                        if (START_CHAR(tty) != __DISABLED_CHAR)
+                                return send_prio_char(tty, START_CHAR(tty));
+                        break;
+                default:
+                        return -EINVAL;
+                }
+                return 0;
+        case TCFLSH:
+                return tty_perform_flush(tty, arg);
+        case TIOCPKT:
+        {
+                int pktmode;
+
+                if (tty->driver->type != TTY_DRIVER_TYPE_PTY ||
+                    tty->driver->subtype != PTY_TYPE_MASTER)
+                        return -ENOTTY;
+                if (get_user(pktmode, (int __user *) arg))
+                        return -EFAULT;
+                spin_lock_irqsave(&tty->ctrl_lock, flags);
+                if (pktmode) {
+                        if (!tty->packet) {
+                                tty->packet = 1;
+                                tty->link->ctrl_status = 0;
+                        }
+                } else
+                        tty->packet = 0;
+                spin_unlock_irqrestore(&tty->ctrl_lock, flags);
+                return 0;
+        }
+        default:
+                /* Try the mode commands */
+                return tty_mode_ioctl(tty, file, cmd, arg);
+        }
+}
+EXPORT_SYMBOL(n_tty_ioctl_helper);