edac: add e752x parameter for sysbus_parity selection
[safe/jmp/linux-2.6] / drivers / char / tty_io.c
index 5289254..98b65a2 100644 (file)
@@ -19,7 +19,7 @@
  * Also restructured routines so that there is more of a separation
  * between the high-level tty routines (tty_io.c and tty_ioctl.c) and
  * the low-level tty routines (serial.c, pty.c, console.c).  This
- * makes for cleaner and more compact code.  -TYT, 9/17/92 
+ * makes for cleaner and more compact code.  -TYT, 9/17/92
  *
  * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines
  * which can be dynamically activated and de-activated by the line
@@ -41,7 +41,7 @@
  *
  * New TIOCLINUX variants added.
  *     -- mj@k332.feld.cvut.cz, 19-Nov-95
- * 
+ *
  * Restrict vt switching via ioctl()
  *      -- grif@cs.ucr.edu, 5-Dec-95
  *
@@ -62,7 +62,8 @@
  *      -- Russell King <rmk@arm.linux.org.uk>
  *
  * Move do_SAK() into process context.  Less stack use in devfs functions.
- * alloc_tty_struct() always uses kmalloc() -- Andrew Morton <andrewm@uow.edu.eu> 17Mar01
+ * alloc_tty_struct() always uses kmalloc()
+ *                      -- Andrew Morton <andrewm@uow.edu.eu> 17Mar01
  */
 
 #include <linux/types.h>
 #include <linux/selection.h>
 
 #include <linux/kmod.h>
+#include <linux/nsproxy.h>
 
 #undef TTY_DEBUG_HANGUP
 
@@ -125,7 +127,7 @@ EXPORT_SYMBOL(tty_std_termios);
 /* This list gets poked at by procfs and various bits of boot up code. This
    could do with some rationalisation such as pulling the tty proc function
    into this file */
-   
+
 LIST_HEAD(tty_drivers);                        /* linked list of tty drivers */
 
 /* Mutex to protect creating and releasing a tty. This is shared with
@@ -135,28 +137,33 @@ EXPORT_SYMBOL(tty_mutex);
 
 #ifdef CONFIG_UNIX98_PTYS
 extern struct tty_driver *ptm_driver;  /* Unix98 pty masters; for /dev/ptmx */
-extern int pty_limit;          /* Config limit on Unix98 ptys */
+extern int pty_limit;                  /* Config limit on Unix98 ptys */
 static DEFINE_IDR(allocated_ptys);
-static DECLARE_MUTEX(allocated_ptys_lock);
+static DEFINE_MUTEX(allocated_ptys_lock);
 static int ptmx_open(struct inode *, struct file *);
 #endif
 
-extern void disable_early_printk(void);
-
 static void initialize_tty_struct(struct tty_struct *tty);
 
 static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *);
 static ssize_t tty_write(struct file *, const char __user *, size_t, loff_t *);
-ssize_t redirected_tty_write(struct file *, const char __user *, size_t, loff_t *);
+ssize_t redirected_tty_write(struct file *, const char __user *,
+                                                       size_t, loff_t *);
 static unsigned int tty_poll(struct file *, poll_table *);
 static int tty_open(struct inode *, struct file *);
 static int tty_release(struct inode *, struct file *);
-int tty_ioctl(struct inode * inode, struct file * file,
+int tty_ioctl(struct inode *inode, struct file *file,
              unsigned int cmd, unsigned long arg);
-static int tty_fasync(int fd, struct file * filp, int on);
+#ifdef CONFIG_COMPAT
+static long tty_compat_ioctl(struct file *file, unsigned int cmd,
+                               unsigned long arg);
+#else
+#define tty_compat_ioctl NULL
+#endif
+static int tty_fasync(int fd, struct file *filp, int on);
 static void release_tty(struct tty_struct *tty, int idx);
-static struct pid *__proc_set_tty(struct task_struct *tsk,
-                               struct tty_struct *tty);
+static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty);
+static void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty);
 
 /**
  *     alloc_tty_struct        -       allocate a tty object
@@ -239,7 +246,7 @@ static int check_tty_count(struct tty_struct *tty, const char *routine)
 #ifdef CHECK_TTY_COUNT
        struct list_head *p;
        int count = 0;
-       
+
        file_list_lock();
        list_for_each(p, &tty->tty_files) {
                count++;
@@ -276,11 +283,11 @@ static int check_tty_count(struct tty_struct *tty, const char *routine)
 static void tty_buffer_free_all(struct tty_struct *tty)
 {
        struct tty_buffer *thead;
-       while((thead = tty->buf.head) != NULL) {
+       while ((thead = tty->buf.head) != NULL) {
                tty->buf.head = thead->next;
                kfree(thead);
        }
-       while((thead = tty->buf.free) != NULL) {
+       while ((thead = tty->buf.free) != NULL) {
                tty->buf.free = thead->next;
                kfree(thead);
        }
@@ -326,7 +333,7 @@ static struct tty_buffer *tty_buffer_alloc(struct tty_struct *tty, size_t size)
        if (tty->buf.memory_used + size > 65536)
                return NULL;
        p = kmalloc(sizeof(struct tty_buffer) + 2 * size, GFP_ATOMIC);
-       if(p == NULL)
+       if (p == NULL)
                return NULL;
        p->used = 0;
        p->size = size;
@@ -356,7 +363,7 @@ static void tty_buffer_free(struct tty_struct *tty, struct tty_buffer *b)
        tty->buf.memory_used -= b->size;
        WARN_ON(tty->buf.memory_used < 0);
 
-       if(b->size >= 512)
+       if (b->size >= 512)
                kfree(b);
        else {
                b->next = tty->buf.free;
@@ -365,6 +372,58 @@ static void tty_buffer_free(struct tty_struct *tty, struct tty_buffer *b)
 }
 
 /**
+ *     __tty_buffer_flush              -       flush full tty buffers
+ *     @tty: tty to flush
+ *
+ *     flush all the buffers containing receive data. Caller must
+ *     hold the buffer lock and must have ensured no parallel flush to
+ *     ldisc is running.
+ *
+ *     Locking: Caller must hold tty->buf.lock
+ */
+
+static void __tty_buffer_flush(struct tty_struct *tty)
+{
+       struct tty_buffer *thead;
+
+       while ((thead = tty->buf.head) != NULL) {
+               tty->buf.head = thead->next;
+               tty_buffer_free(tty, thead);
+       }
+       tty->buf.tail = NULL;
+}
+
+/**
+ *     tty_buffer_flush                -       flush full tty buffers
+ *     @tty: tty to flush
+ *
+ *     flush all the buffers containing receive data. If the buffer is
+ *     being processed by flush_to_ldisc then we defer the processing
+ *     to that function
+ *
+ *     Locking: none
+ */
+
+static void tty_buffer_flush(struct tty_struct *tty)
+{
+       unsigned long flags;
+       spin_lock_irqsave(&tty->buf.lock, flags);
+
+       /* If the data is being pushed to the tty layer then we can't
+          process it here. Instead set a flag and the flush_to_ldisc
+          path will process the flush request before it exits */
+       if (test_bit(TTY_FLUSHING, &tty->flags)) {
+               set_bit(TTY_FLUSHPENDING, &tty->flags);
+               spin_unlock_irqrestore(&tty->buf.lock, flags);
+               wait_event(tty->read_wait,
+                               test_bit(TTY_FLUSHPENDING, &tty->flags) == 0);
+               return;
+       } else
+               __tty_buffer_flush(tty);
+       spin_unlock_irqrestore(&tty->buf.lock, flags);
+}
+
+/**
  *     tty_buffer_find         -       find a free tty buffer
  *     @tty: tty owning the buffer
  *     @size: characters wanted
@@ -379,9 +438,9 @@ static void tty_buffer_free(struct tty_struct *tty, struct tty_buffer *b)
 static struct tty_buffer *tty_buffer_find(struct tty_struct *tty, size_t size)
 {
        struct tty_buffer **tbh = &tty->buf.free;
-       while((*tbh) != NULL) {
+       while ((*tbh) != NULL) {
                struct tty_buffer *t = *tbh;
-               if(t->size >= size) {
+               if (t->size >= size) {
                        *tbh = t->next;
                        t->next = NULL;
                        t->used = 0;
@@ -393,7 +452,7 @@ static struct tty_buffer *tty_buffer_find(struct tty_struct *tty, size_t size)
                tbh = &((*tbh)->next);
        }
        /* Round the buffer size out */
-       size = (size + 0xFF) & ~ 0xFF;
+       size = (size + 0xFF) & ~0xFF;
        return tty_buffer_alloc(tty, size);
        /* Should possibly check if this fails for the largest buffer we
           have queued and recycle that ? */
@@ -463,7 +522,7 @@ int tty_insert_flip_string(struct tty_struct *tty, const unsigned char *chars,
                int space = tty_buffer_request_room(tty, size - copied);
                struct tty_buffer *tb = tty->buf.tail;
                /* If there is no space then tb may be NULL */
-               if(unlikely(space == 0))
+               if (unlikely(space == 0))
                        break;
                memcpy(tb->char_buf_ptr + tb->used, chars, space);
                memset(tb->flag_buf_ptr + tb->used, TTY_NORMAL, space);
@@ -499,7 +558,7 @@ int tty_insert_flip_string_flags(struct tty_struct *tty,
                int space = tty_buffer_request_room(tty, size - copied);
                struct tty_buffer *tb = tty->buf.tail;
                /* If there is no space then tb may be NULL */
-               if(unlikely(space == 0))
+               if (unlikely(space == 0))
                        break;
                memcpy(tb->char_buf_ptr + tb->used, chars, space);
                memcpy(tb->flag_buf_ptr + tb->used, flags, space);
@@ -551,7 +610,8 @@ EXPORT_SYMBOL(tty_schedule_flip);
  *     Locking: May call functions taking tty->buf.lock
  */
 
-int tty_prepare_flip_string(struct tty_struct *tty, unsigned char **chars, size_t size)
+int tty_prepare_flip_string(struct tty_struct *tty, unsigned char **chars,
+                                                               size_t size)
 {
        int space = tty_buffer_request_room(tty, size);
        if (likely(space)) {
@@ -581,7 +641,8 @@ EXPORT_SYMBOL_GPL(tty_prepare_flip_string);
  *     Locking: May call functions taking tty->buf.lock
  */
 
-int tty_prepare_flip_string_flags(struct tty_struct *tty, unsigned char **chars, char **flags, size_t size)
+int tty_prepare_flip_string_flags(struct tty_struct *tty,
+                       unsigned char **chars, char **flags, size_t size)
 {
        int space = tty_buffer_request_room(tty, size);
        if (likely(space)) {
@@ -603,12 +664,12 @@ EXPORT_SYMBOL_GPL(tty_prepare_flip_string_flags);
  *     @num: line discipline number
  *
  *     This is probably overkill for real world processors but
- *     they are not on hot paths so a little discipline won't do 
+ *     they are not on hot paths so a little discipline won't do
  *     any harm.
  *
  *     Locking: takes termios_mutex
  */
+
 static void tty_set_termios_ldisc(struct tty_struct *tty, int num)
 {
        mutex_lock(&tty->termios_mutex);
@@ -621,10 +682,11 @@ static void tty_set_termios_ldisc(struct tty_struct *tty, int num)
  *     must be taken with irqs off because there are hangup path
  *     callers who will do ldisc lookups and cannot sleep.
  */
+
 static DEFINE_SPINLOCK(tty_ldisc_lock);
 static DECLARE_WAIT_QUEUE_HEAD(tty_ldisc_wait);
-static struct tty_ldisc tty_ldiscs[NR_LDISCS]; /* line disc dispatch table */
+/* Line disc dispatch table */
+static struct tty_ldisc tty_ldiscs[NR_LDISCS];
 
 /**
  *     tty_register_ldisc      -       install a line discipline
@@ -643,17 +705,17 @@ int tty_register_ldisc(int disc, struct tty_ldisc *new_ldisc)
 {
        unsigned long flags;
        int ret = 0;
-       
+
        if (disc < N_TTY || disc >= NR_LDISCS)
                return -EINVAL;
-       
+
        spin_lock_irqsave(&tty_ldisc_lock, flags);
        tty_ldiscs[disc] = *new_ldisc;
        tty_ldiscs[disc].num = disc;
        tty_ldiscs[disc].flags |= LDISC_FLAG_DEFINED;
        tty_ldiscs[disc].refcount = 0;
        spin_unlock_irqrestore(&tty_ldisc_lock, flags);
-       
+
        return ret;
 }
 EXPORT_SYMBOL(tty_register_ldisc);
@@ -709,20 +771,18 @@ struct tty_ldisc *tty_ldisc_get(int disc)
 
        if (disc < N_TTY || disc >= NR_LDISCS)
                return NULL;
-       
+
        spin_lock_irqsave(&tty_ldisc_lock, flags);
 
        ld = &tty_ldiscs[disc];
        /* Check the entry is defined */
-       if(ld->flags & LDISC_FLAG_DEFINED)
-       {
+       if (ld->flags & LDISC_FLAG_DEFINED) {
                /* If the module is being unloaded we can't use it */
                if (!try_module_get(ld->owner))
-                       ld = NULL;
+                       ld = NULL;
                else /* lock it */
                        ld->refcount++;
-       }
-       else
+       } else
                ld = NULL;
        spin_unlock_irqrestore(&tty_ldisc_lock, flags);
        return ld;
@@ -745,9 +805,9 @@ void tty_ldisc_put(int disc)
 {
        struct tty_ldisc *ld;
        unsigned long flags;
-       
+
        BUG_ON(disc < N_TTY || disc >= NR_LDISCS);
-               
+
        spin_lock_irqsave(&tty_ldisc_lock, flags);
        ld = &tty_ldiscs[disc];
        BUG_ON(ld->refcount == 0);
@@ -755,7 +815,7 @@ void tty_ldisc_put(int disc)
        module_put(ld->owner);
        spin_unlock_irqrestore(&tty_ldisc_lock, flags);
 }
-       
+
 EXPORT_SYMBOL_GPL(tty_ldisc_put);
 
 /**
@@ -794,11 +854,10 @@ static int tty_ldisc_try(struct tty_struct *tty)
        unsigned long flags;
        struct tty_ldisc *ld;
        int ret = 0;
-       
+
        spin_lock_irqsave(&tty_ldisc_lock, flags);
        ld = &tty->ldisc;
-       if(test_bit(TTY_LDISC, &tty->flags))
-       {
+       if (test_bit(TTY_LDISC, &tty->flags)) {
                ld->refcount++;
                ret = 1;
        }
@@ -810,8 +869,8 @@ static int tty_ldisc_try(struct tty_struct *tty)
  *     tty_ldisc_ref_wait      -       wait for the tty ldisc
  *     @tty: tty device
  *
- *     Dereference the line discipline for the terminal and take a 
- *     reference to it. If the line discipline is in flux then 
+ *     Dereference the line discipline for the terminal and take a
+ *     reference to it. If the line discipline is in flux then
  *     wait patiently until it changes.
  *
  *     Note: Must not be called from an IRQ/timer context. The caller
@@ -821,12 +880,12 @@ static int tty_ldisc_try(struct tty_struct *tty)
  *
  *     Locking: call functions take tty_ldisc_lock
  */
+
 struct tty_ldisc *tty_ldisc_ref_wait(struct tty_struct *tty)
 {
        /* wait_event is a macro */
        wait_event(tty_ldisc_wait, tty_ldisc_try(tty));
-       if(tty->ldisc.refcount == 0)
+       if (tty->ldisc.refcount == 0)
                printk(KERN_ERR "tty_ldisc_ref_wait\n");
        return &tty->ldisc;
 }
@@ -837,16 +896,16 @@ EXPORT_SYMBOL_GPL(tty_ldisc_ref_wait);
  *     tty_ldisc_ref           -       get the tty ldisc
  *     @tty: tty device
  *
- *     Dereference the line discipline for the terminal and take a 
- *     reference to it. If the line discipline is in flux then 
+ *     Dereference the line discipline for the terminal and take a
+ *     reference to it. If the line discipline is in flux then
  *     return NULL. Can be called from IRQ and timer functions.
  *
  *     Locking: called functions take tty_ldisc_lock
  */
+
 struct tty_ldisc *tty_ldisc_ref(struct tty_struct *tty)
 {
-       if(tty_ldisc_try(tty))
+       if (tty_ldisc_try(tty))
                return &tty->ldisc;
        return NULL;
 }
@@ -862,19 +921,19 @@ EXPORT_SYMBOL_GPL(tty_ldisc_ref);
  *
  *     Locking: takes tty_ldisc_lock
  */
+
 void tty_ldisc_deref(struct tty_ldisc *ld)
 {
        unsigned long flags;
 
        BUG_ON(ld == NULL);
-               
+
        spin_lock_irqsave(&tty_ldisc_lock, flags);
-       if(ld->refcount == 0)
+       if (ld->refcount == 0)
                printk(KERN_ERR "tty_ldisc_deref: no references.\n");
        else
                ld->refcount--;
-       if(ld->refcount == 0)
+       if (ld->refcount == 0)
                wake_up(&tty_ldisc_wait);
        spin_unlock_irqrestore(&tty_ldisc_lock, flags);
 }
@@ -886,7 +945,7 @@ EXPORT_SYMBOL_GPL(tty_ldisc_deref);
  *     @tty: terminal to activate ldisc on
  *
  *     Set the TTY_LDISC flag when the line discipline can be called
- *     again. Do neccessary wakeups for existing sleepers.
+ *     again. Do necessary wakeups for existing sleepers.
  *
  *     Note: nobody should set this bit except via this function. Clearing
  *     directly is allowed.
@@ -897,7 +956,7 @@ static void tty_ldisc_enable(struct tty_struct *tty)
        set_bit(TTY_LDISC, &tty->flags);
        wake_up(&tty_ldisc_wait);
 }
-       
+
 /**
  *     tty_set_ldisc           -       set line discipline
  *     @tty: the terminal to set
@@ -909,7 +968,7 @@ static void tty_ldisc_enable(struct tty_struct *tty)
  *     Locking: takes tty_ldisc_lock.
  *              called functions take termios_mutex
  */
+
 static int tty_set_ldisc(struct tty_struct *tty, int ldisc)
 {
        int retval = 0;
@@ -936,13 +995,6 @@ restart:
                return -EINVAL;
 
        /*
-        *      No more input please, we are switching. The new ldisc
-        *      will update this value in the ldisc open function
-        */
-
-       tty->receive_room = 0;
-
-       /*
         *      Problem: What do we do if this blocks ?
         */
 
@@ -953,6 +1005,13 @@ restart:
                return 0;
        }
 
+       /*
+        *      No more input please, we are switching. The new ldisc
+        *      will update this value in the ldisc open function
+        */
+
+       tty->receive_room = 0;
+
        o_ldisc = tty->ldisc;
        o_tty = tty->link;
 
@@ -965,7 +1024,7 @@ restart:
 
        spin_lock_irqsave(&tty_ldisc_lock, flags);
        if (tty->ldisc.refcount || (o_tty && o_tty->ldisc.refcount)) {
-               if(tty->ldisc.refcount) {
+               if (tty->ldisc.refcount) {
                        /* Free the new ldisc we grabbed. Must drop the lock
                           first. */
                        spin_unlock_irqrestore(&tty_ldisc_lock, flags);
@@ -974,14 +1033,14 @@ restart:
                         * There are several reasons we may be busy, including
                         * random momentary I/O traffic. We must therefore
                         * retry. We could distinguish between blocking ops
-                        * and retries if we made tty_ldisc_wait() smarter. That
-                        * is up for discussion.
+                        * and retries if we made tty_ldisc_wait() smarter.
+                        * That is up for discussion.
                         */
                        if (wait_event_interruptible(tty_ldisc_wait, tty->ldisc.refcount == 0) < 0)
                                return -ERESTARTSYS;
                        goto restart;
                }
-               if(o_tty && o_tty->ldisc.refcount) {
+               if (o_tty && o_tty->ldisc.refcount) {
                        spin_unlock_irqrestore(&tty_ldisc_lock, flags);
                        tty_ldisc_put(ldisc);
                        if (wait_event_interruptible(tty_ldisc_wait, o_tty->ldisc.refcount == 0) < 0)
@@ -989,9 +1048,10 @@ restart:
                        goto restart;
                }
        }
-
-       /* if the TTY_LDISC bit is set, then we are racing against another ldisc change */
-
+       /*
+        *      If the TTY_LDISC bit is set, then we are racing against
+        *      another ldisc change
+        */
        if (!test_bit(TTY_LDISC, &tty->flags)) {
                spin_unlock_irqrestore(&tty_ldisc_lock, flags);
                tty_ldisc_put(ldisc);
@@ -1015,7 +1075,6 @@ restart:
        /*
         * Wait for ->hangup_work and ->buf.work handlers to terminate
         */
-        
        flush_scheduled_work();
        /* Shutdown the current discipline. */
        if (tty->ldisc.close)
@@ -1049,21 +1108,21 @@ restart:
        /* At this point we hold a reference to the new ldisc and a
           a reference to the old ldisc. If we ended up flipping back
           to the existing ldisc we have two references to it */
-       
+
        if (tty->ldisc.num != o_ldisc.num && tty->driver->set_ldisc)
                tty->driver->set_ldisc(tty);
-               
+
        tty_ldisc_put(o_ldisc.num);
-       
+
        /*
         *      Allow ldisc referencing to occur as soon as the driver
         *      ldisc callback completes.
         */
-        
+
        tty_ldisc_enable(tty);
        if (o_tty)
                tty_ldisc_enable(o_tty);
-       
+
        /* Restart it in case no characters kick it off. Safe if
           already running */
        if (work)
@@ -1096,6 +1155,48 @@ static struct tty_driver *get_tty_driver(dev_t device, int *index)
        return NULL;
 }
 
+#ifdef CONFIG_CONSOLE_POLL
+
+/**
+ *     tty_find_polling_driver -       find device of a polled tty
+ *     @name: name string to match
+ *     @line: pointer to resulting tty line nr
+ *
+ *     This routine returns a tty driver structure, given a name
+ *     and the condition that the tty driver is capable of polled
+ *     operation.
+ */
+struct tty_driver *tty_find_polling_driver(char *name, int *line)
+{
+       struct tty_driver *p, *res = NULL;
+       int tty_line = 0;
+       char *str;
+
+       mutex_lock(&tty_mutex);
+       /* Search through the tty devices to look for a match */
+       list_for_each_entry(p, &tty_drivers, tty_drivers) {
+               str = name + strlen(p->name);
+               tty_line = simple_strtoul(str, &str, 10);
+               if (*str == ',')
+                       str++;
+               if (*str == '\0')
+                       str = NULL;
+
+               if (tty_line >= 0 && tty_line <= p->num && p->poll_init &&
+                               !p->poll_init(p, tty_line, str)) {
+
+                       res = p;
+                       *line = tty_line;
+                       break;
+               }
+       }
+       mutex_unlock(&tty_mutex);
+
+       return res;
+}
+EXPORT_SYMBOL_GPL(tty_find_polling_driver);
+#endif
+
 /**
  *     tty_check_change        -       check for POSIX terminal changes
  *     @tty: tty to check
@@ -1107,7 +1208,7 @@ static struct tty_driver *get_tty_driver(dev_t device, int *index)
  *     Locking: none
  */
 
-int tty_check_change(struct tty_struct * tty)
+int tty_check_change(struct tty_struct *tty)
 {
        if (current->signal->tty != tty)
                return 0;
@@ -1121,42 +1222,50 @@ int tty_check_change(struct tty_struct * tty)
                return 0;
        if (is_current_pgrp_orphaned())
                return -EIO;
-       (void) kill_pgrp(task_pgrp(current), SIGTTOU, 1);
+       kill_pgrp(task_pgrp(current), SIGTTOU, 1);
+       set_thread_flag(TIF_SIGPENDING);
        return -ERESTARTSYS;
 }
 
 EXPORT_SYMBOL(tty_check_change);
 
-static ssize_t hung_up_tty_read(struct file * file, char __user * buf,
+static ssize_t hung_up_tty_read(struct file *file, char __user *buf,
                                size_t count, loff_t *ppos)
 {
        return 0;
 }
 
-static ssize_t hung_up_tty_write(struct file * file, const char __user * buf,
+static ssize_t hung_up_tty_write(struct file *file, const char __user *buf,
                                 size_t count, loff_t *ppos)
 {
        return -EIO;
 }
 
 /* No kernel lock held - none needed ;) */
-static unsigned int hung_up_tty_poll(struct file * filp, poll_table * wait)
+static unsigned int hung_up_tty_poll(struct file *filp, poll_table *wait)
 {
        return POLLIN | POLLOUT | POLLERR | POLLHUP | POLLRDNORM | POLLWRNORM;
 }
 
-static int hung_up_tty_ioctl(struct inode * inode, struct file * file,
+static int hung_up_tty_ioctl(struct inode *inode, struct file *file,
                             unsigned int cmd, unsigned long arg)
 {
        return cmd == TIOCSPGRP ? -ENOTTY : -EIO;
 }
 
+static long hung_up_tty_compat_ioctl(struct file *file,
+                                    unsigned int cmd, unsigned long arg)
+{
+       return cmd == TIOCSPGRP ? -ENOTTY : -EIO;
+}
+
 static const struct file_operations tty_fops = {
        .llseek         = no_llseek,
        .read           = tty_read,
        .write          = tty_write,
        .poll           = tty_poll,
        .ioctl          = tty_ioctl,
+       .compat_ioctl   = tty_compat_ioctl,
        .open           = tty_open,
        .release        = tty_release,
        .fasync         = tty_fasync,
@@ -1169,6 +1278,7 @@ static const struct file_operations ptmx_fops = {
        .write          = tty_write,
        .poll           = tty_poll,
        .ioctl          = tty_ioctl,
+       .compat_ioctl   = tty_compat_ioctl,
        .open           = ptmx_open,
        .release        = tty_release,
        .fasync         = tty_fasync,
@@ -1181,6 +1291,7 @@ static const struct file_operations console_fops = {
        .write          = redirected_tty_write,
        .poll           = tty_poll,
        .ioctl          = tty_ioctl,
+       .compat_ioctl   = tty_compat_ioctl,
        .open           = tty_open,
        .release        = tty_release,
        .fasync         = tty_fasync,
@@ -1192,6 +1303,7 @@ static const struct file_operations hung_up_tty_fops = {
        .write          = hung_up_tty_write,
        .poll           = hung_up_tty_poll,
        .ioctl          = hung_up_tty_ioctl,
+       .compat_ioctl   = hung_up_tty_compat_ioctl,
        .release        = tty_release,
 };
 
@@ -1206,15 +1318,15 @@ static struct file *redirect;
  *     informs the line discipline if present that the driver is ready
  *     to receive more output data.
  */
+
 void tty_wakeup(struct tty_struct *tty)
 {
        struct tty_ldisc *ld;
-       
+
        if (test_bit(TTY_DO_WRITE_WAKEUP, &tty->flags)) {
                ld = tty_ldisc_ref(tty);
-               if(ld) {
-                       if(ld->write_wakeup)
+               if (ld) {
+                       if (ld->write_wakeup)
                                ld->write_wakeup(tty);
                        tty_ldisc_deref(ld);
                }
@@ -1231,15 +1343,16 @@ EXPORT_SYMBOL_GPL(tty_wakeup);
  *     Flush the line discipline queue (if any) for this tty. If there
  *     is no line discipline active this is a no-op.
  */
+
 void tty_ldisc_flush(struct tty_struct *tty)
 {
        struct tty_ldisc *ld = tty_ldisc_ref(tty);
-       if(ld) {
-               if(ld->flush_buffer)
+       if (ld) {
+               if (ld->flush_buffer)
                        ld->flush_buffer(tty);
                tty_ldisc_deref(ld);
        }
+       tty_buffer_flush(tty);
 }
 
 EXPORT_SYMBOL_GPL(tty_ldisc_flush);
@@ -1259,7 +1372,7 @@ static void tty_reset_termios(struct tty_struct *tty)
        tty->termios->c_ospeed = tty_termios_baud_rate(tty->termios);
        mutex_unlock(&tty->termios_mutex);
 }
-       
+
 /**
  *     do_tty_hangup           -       actual handler for hangup events
  *     @work: tty device
@@ -1286,7 +1399,7 @@ static void do_tty_hangup(struct work_struct *work)
 {
        struct tty_struct *tty =
                container_of(work, struct tty_struct, hangup_work);
-       struct file * cons_filp = NULL;
+       struct file *cons_filp = NULL;
        struct file *filp, *f = NULL;
        struct task_struct *p;
        struct tty_ldisc *ld;
@@ -1304,7 +1417,7 @@ static void do_tty_hangup(struct work_struct *work)
                redirect = NULL;
        }
        spin_unlock(&redirect_lock);
-       
+
        check_tty_count(tty, "do_tty_hangup");
        file_list_lock();
        /* This breaks for file handles being sent over AF_UNIX sockets ? */
@@ -1318,13 +1431,14 @@ static void do_tty_hangup(struct work_struct *work)
                filp->f_op = &hung_up_tty_fops;
        }
        file_list_unlock();
-       
-       /* FIXME! What are the locking issues here? This may me overdoing things..
-        * this question is especially important now that we've removed the irqlock. */
-
+       /*
+        * FIXME! What are the locking issues here? This may me overdoing
+        * things... This question is especially important now that we've
+        * removed the irqlock.
+        */
        ld = tty_ldisc_ref(tty);
-       if(ld != NULL)  /* We may have no line discipline at this point */
-       {
+       if (ld != NULL) {
+               /* We may have no line discipline at this point */
                if (ld->flush_buffer)
                        ld->flush_buffer(tty);
                if (tty->driver->flush_buffer)
@@ -1335,26 +1449,24 @@ static void do_tty_hangup(struct work_struct *work)
                if (ld->hangup)
                        ld->hangup(tty);
        }
-
-       /* FIXME: Once we trust the LDISC code better we can wait here for
-          ldisc completion and fix the driver call race */
-          
+       /*
+        * FIXME: Once we trust the LDISC code better we can wait here for
+        * ldisc completion and fix the driver call race
+        */
        wake_up_interruptible(&tty->write_wait);
        wake_up_interruptible(&tty->read_wait);
-
        /*
         * Shutdown the current line discipline, and reset it to
         * N_TTY.
         */
        if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS)
                tty_reset_termios(tty);
-       
        /* Defer ldisc switch */
        /* tty_deferred_ldisc_switch(N_TTY);
-       
+
          This should get done automatically when the port closes and
          tty_release is called */
-       
+
        read_lock(&tasklist_lock);
        if (tty->session) {
                do_each_pid_task(tty->session, PIDTYPE_SID, p) {
@@ -1376,14 +1488,16 @@ static void do_tty_hangup(struct work_struct *work)
        read_unlock(&tasklist_lock);
 
        tty->flags = 0;
+       put_pid(tty->session);
+       put_pid(tty->pgrp);
        tty->session = NULL;
        tty->pgrp = NULL;
        tty->ctrl_status = 0;
        /*
-        *      If one of the devices matches a console pointer, we
-        *      cannot just call hangup() because that will cause
-        *      tty->count and state->count to go out of sync.
-        *      So we just call close() the right number of times.
+        * If one of the devices matches a console pointer, we
+        * cannot just call hangup() because that will cause
+        * tty->count and state->count to go out of sync.
+        * So we just call close() the right number of times.
         */
        if (cons_filp) {
                if (tty->driver->close)
@@ -1391,12 +1505,12 @@ static void do_tty_hangup(struct work_struct *work)
                                tty->driver->close(tty, cons_filp);
        } else if (tty->driver->hangup)
                (tty->driver->hangup)(tty);
-               
-       /* We don't want to have driver/ldisc interactions beyond
-          the ones we did here. The driver layer expects no
-          calls after ->hangup() from the ldisc side. However we
-          can't yet guarantee all that */
-
+       /*
+        * We don't want to have driver/ldisc interactions beyond
+        * the ones we did here. The driver layer expects no
+        * calls after ->hangup() from the ldisc side. However we
+        * can't yet guarantee all that.
+        */
        set_bit(TTY_HUPPED, &tty->flags);
        if (ld) {
                tty_ldisc_enable(tty);
@@ -1415,11 +1529,10 @@ static void do_tty_hangup(struct work_struct *work)
  *     schedule a hangup sequence to run after this event.
  */
 
-void tty_hangup(struct tty_struct * tty)
+void tty_hangup(struct tty_struct *tty)
 {
 #ifdef TTY_DEBUG_HANGUP
        char    buf[64];
-       
        printk(KERN_DEBUG "%s hangup...\n", tty_name(tty, buf));
 #endif
        schedule_work(&tty->hangup_work);
@@ -1433,10 +1546,10 @@ EXPORT_SYMBOL(tty_hangup);
  *
  *     The user has asked via system call for the terminal to be hung up.
  *     We do this synchronously so that when the syscall returns the process
- *     is complete. That guarantee is neccessary for security reasons.
+ *     is complete. That guarantee is necessary for security reasons.
  */
 
-void tty_vhangup(struct tty_struct * tty)
+void tty_vhangup(struct tty_struct *tty)
 {
 #ifdef TTY_DEBUG_HANGUP
        char    buf[64];
@@ -1445,6 +1558,7 @@ void tty_vhangup(struct tty_struct * tty)
 #endif
        do_tty_hangup(&tty->hangup_work);
 }
+
 EXPORT_SYMBOL(tty_vhangup);
 
 /**
@@ -1455,13 +1569,26 @@ EXPORT_SYMBOL(tty_vhangup);
  *     loss
  */
 
-int tty_hung_up_p(struct file * filp)
+int tty_hung_up_p(struct file *filp)
 {
        return (filp->f_op == &hung_up_tty_fops);
 }
 
 EXPORT_SYMBOL(tty_hung_up_p);
 
+/**
+ *     is_tty  -       checker whether file is a TTY
+ *     @filp:          file handle that may be a tty
+ *
+ *     Check if the file handle is a tty handle.
+ */
+
+int is_tty(struct file *filp)
+{
+       return filp->f_op->read == tty_read
+               || filp->f_op->read == hung_up_tty_read;
+}
+
 static void session_clear_tty(struct pid *session)
 {
        struct task_struct *p;
@@ -1521,7 +1648,7 @@ void disassociate_ctty(int on_exit)
                        put_pid(old_pgrp);
                }
                mutex_unlock(&tty_mutex);
-               unlock_kernel();        
+               unlock_kernel();
                return;
        }
        if (tty_pgrp) {
@@ -1532,10 +1659,9 @@ void disassociate_ctty(int on_exit)
        }
 
        spin_lock_irq(&current->sighand->siglock);
-       tty_pgrp = current->signal->tty_old_pgrp;
-       current->signal->tty_old_pgrp = 0;
+       put_pid(current->signal->tty_old_pgrp);
+       current->signal->tty_old_pgrp = NULL;
        spin_unlock_irq(&current->sighand->siglock);
-       put_pid(tty_pgrp);
 
        mutex_lock(&tty_mutex);
        /* It is possible that do_tty_hangup has free'd this tty */
@@ -1560,13 +1686,25 @@ void disassociate_ctty(int on_exit)
        unlock_kernel();
 }
 
+/**
+ *
+ *     no_tty  - Ensure the current process does not have a controlling tty
+ */
+void no_tty(void)
+{
+       struct task_struct *tsk = current;
+       if (tsk->signal->leader)
+               disassociate_ctty(0);
+       proc_clear_tty(tsk);
+}
+
 
 /**
- *     stop_tty        -       propogate flow control
+ *     stop_tty        -       propagate flow control
  *     @tty: tty to stop
  *
  *     Perform flow control to the driver. For PTY/TTY pairs we
- *     must also propogate the TIOCKPKT status. May be called
+ *     must also propagate the TIOCKPKT status. May be called
  *     on an already stopped device and will not re-call the driver
  *     method.
  *
@@ -1596,11 +1734,11 @@ void stop_tty(struct tty_struct *tty)
 EXPORT_SYMBOL(stop_tty);
 
 /**
- *     start_tty       -       propogate flow control
+ *     start_tty       -       propagate flow control
  *     @tty: tty to start
  *
  *     Start a tty that has been stopped if at all possible. Perform
- *     any neccessary wakeups and propogate the TIOCPKT status. If this
+ *     any necessary wakeups and propagate the TIOCPKT status. If this
  *     is the tty was previous stopped and is being started then the
  *     driver start method is invoked and the line discipline woken.
  *
@@ -1620,7 +1758,6 @@ void start_tty(struct tty_struct *tty)
        }
        if (tty->driver->start)
                (tty->driver->start)(tty);
-
        /* If we have a running line discipline it may need kicking */
        tty_wakeup(tty);
 }
@@ -1644,11 +1781,11 @@ EXPORT_SYMBOL(start_tty);
  *     in new code. Multiple read calls may be outstanding in parallel.
  */
 
-static ssize_t tty_read(struct file * file, char __user * buf, size_t count, 
+static ssize_t tty_read(struct file *file, char __user *buf, size_t count,
                        loff_t *ppos)
 {
        int i;
-       struct tty_struct * tty;
+       struct tty_struct *tty;
        struct inode *inode;
        struct tty_ldisc *ld;
 
@@ -1664,7 +1801,7 @@ static ssize_t tty_read(struct file * file, char __user * buf, size_t count,
        ld = tty_ldisc_ref_wait(tty);
        lock_kernel();
        if (ld->read)
-               i = (ld->read)(tty,file,buf,count);
+               i = (ld->read)(tty, file, buf, count);
        else
                i = -EIO;
        tty_ldisc_deref(ld);
@@ -1674,6 +1811,23 @@ static ssize_t tty_read(struct file * file, char __user * buf, size_t count,
        return i;
 }
 
+void tty_write_unlock(struct tty_struct *tty)
+{
+       mutex_unlock(&tty->atomic_write_lock);
+       wake_up_interruptible(&tty->write_wait);
+}
+
+int tty_write_lock(struct tty_struct *tty, int ndelay)
+{
+       if (!mutex_trylock(&tty->atomic_write_lock)) {
+               if (ndelay)
+                       return -EAGAIN;
+               if (mutex_lock_interruptible(&tty->atomic_write_lock))
+                       return -ERESTARTSYS;
+       }
+       return 0;
+}
+
 /*
  * Split writes up in sane blocksizes to avoid
  * denial-of-service type attacks
@@ -1685,13 +1839,12 @@ static inline ssize_t do_tty_write(
        const char __user *buf,
        size_t count)
 {
-       ssize_t ret = 0, written = 0;
+       ssize_t ret, written = 0;
        unsigned int chunk;
-       
-       /* FIXME: O_NDELAY ... */
-       if (mutex_lock_interruptible(&tty->atomic_write_lock)) {
-               return -ERESTARTSYS;
-       }
+
+       ret = tty_write_lock(tty, file->f_flags & O_NDELAY);
+       if (ret < 0)
+               return ret;
 
        /*
         * We chunk up writes into a temporary buffer. This
@@ -1724,8 +1877,8 @@ static inline ssize_t do_tty_write(
 
                buf = kmalloc(chunk, GFP_KERNEL);
                if (!buf) {
-                       mutex_unlock(&tty->atomic_write_lock);
-                       return -ENOMEM;
+                       ret = -ENOMEM;
+                       goto out;
                }
                kfree(tty->write_buf);
                tty->write_cnt = chunk;
@@ -1760,7 +1913,8 @@ static inline ssize_t do_tty_write(
                inode->i_mtime = current_fs_time(inode->i_sb);
                ret = written;
        }
-       mutex_unlock(&tty->atomic_write_lock);
+out:
+       tty_write_unlock(tty);
        return ret;
 }
 
@@ -1783,21 +1937,22 @@ static inline ssize_t do_tty_write(
  *     kernel lock for historical reasons. New code should not rely on this.
  */
 
-static ssize_t tty_write(struct file * file, const char __user * buf, size_t count,
-                        loff_t *ppos)
+static ssize_t tty_write(struct file *file, const char __user *buf,
+                                               size_t count, loff_t *ppos)
 {
-       struct tty_struct * tty;
+       struct tty_struct *tty;
        struct inode *inode = file->f_path.dentry->d_inode;
        ssize_t ret;
        struct tty_ldisc *ld;
-       
+
        tty = (struct tty_struct *)file->private_data;
        if (tty_paranoia_check(tty, inode, "tty_write"))
                return -EIO;
-       if (!tty || !tty->driver->write || (test_bit(TTY_IO_ERROR, &tty->flags)))
-               return -EIO;
+       if (!tty || !tty->driver->write ||
+               (test_bit(TTY_IO_ERROR, &tty->flags)))
+                       return -EIO;
 
-       ld = tty_ldisc_ref_wait(tty);           
+       ld = tty_ldisc_ref_wait(tty);
        if (!ld->write)
                ret = -EIO;
        else
@@ -1806,8 +1961,8 @@ static ssize_t tty_write(struct file * file, const char __user * buf, size_t cou
        return ret;
 }
 
-ssize_t redirected_tty_write(struct file * file, const char __user * buf, size_t count,
-                        loff_t *ppos)
+ssize_t redirected_tty_write(struct file *file, const char __user *buf,
+                                               size_t count, loff_t *ppos)
 {
        struct file *p = NULL;
 
@@ -1824,7 +1979,6 @@ ssize_t redirected_tty_write(struct file * file, const char __user * buf, size_t
                fput(p);
                return res;
        }
-
        return tty_write(file, buf, count, ppos);
 }
 
@@ -1846,8 +2000,8 @@ static void pty_line_name(struct tty_driver *driver, int index, char *p)
        int i = index + driver->name_base;
        /* ->name is initialized to "ttyp", but "tty" is expected */
        sprintf(p, "%s%c%x",
-                       driver->subtype == PTY_TYPE_SLAVE ? "tty" : driver->name,
-                       ptychar[i >> 4 & 0xf], i & 0xf);
+               driver->subtype == PTY_TYPE_SLAVE ? "tty" : driver->name,
+               ptychar[i >> 4 & 0xf], i & 0xf);
 }
 
 /**
@@ -1901,6 +2055,20 @@ static int init_dev(struct tty_driver *driver, int idx,
        /* check whether we're reopening an existing tty */
        if (driver->flags & TTY_DRIVER_DEVPTS_MEM) {
                tty = devpts_get_tty(idx);
+               /*
+                * If we don't have a tty here on a slave open, it's because
+                * the master already started the close process and there's
+                * no relation between devpts file and tty anymore.
+                */
+               if (!tty && driver->subtype == PTY_TYPE_SLAVE) {
+                       retval = -EIO;
+                       goto end_init;
+               }
+               /*
+                * It's safe from now on because init_dev() is called with
+                * tty_mutex held and release_dev() won't change tty->count
+                * or tty->flags without having to grab tty_mutex
+                */
                if (tty && driver->subtype == PTY_TYPE_MASTER)
                        tty = tty->link;
        } else {
@@ -1912,7 +2080,7 @@ static int init_dev(struct tty_driver *driver, int idx,
         * First time open is complex, especially for PTY devices.
         * This code guarantees that either everything succeeds and the
         * TTY is ready for operation, or else the table slots are vacated
-        * and the allocated memory released.  (Except that the termios 
+        * and the allocated memory released.  (Except that the termios
         * and locked termios may be retained.)
         */
 
@@ -1926,7 +2094,7 @@ static int init_dev(struct tty_driver *driver, int idx,
        ltp = o_ltp = NULL;
 
        tty = alloc_tty_struct();
-       if(!tty)
+       if (!tty)
                goto fail_no_mem;
        initialize_tty_struct(tty);
        tty->driver = driver;
@@ -1942,19 +2110,16 @@ static int init_dev(struct tty_driver *driver, int idx,
        }
 
        if (!*tp_loc) {
-               tp = (struct ktermios *) kmalloc(sizeof(struct ktermios),
-                                               GFP_KERNEL);
+               tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
                if (!tp)
                        goto free_mem_out;
                *tp = driver->init_termios;
        }
 
        if (!*ltp_loc) {
-               ltp = (struct ktermios *) kmalloc(sizeof(struct ktermios),
-                                                GFP_KERNEL);
+               ltp = kzalloc(sizeof(struct ktermios), GFP_KERNEL);
                if (!ltp)
                        goto free_mem_out;
-               memset(ltp, 0, sizeof(struct ktermios));
        }
 
        if (driver->type == TTY_DRIVER_TYPE_PTY) {
@@ -1975,27 +2140,23 @@ static int init_dev(struct tty_driver *driver, int idx,
                }
 
                if (!*o_tp_loc) {
-                       o_tp = (struct ktermios *)
-                               kmalloc(sizeof(struct ktermios), GFP_KERNEL);
+                       o_tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
                        if (!o_tp)
                                goto free_mem_out;
                        *o_tp = driver->other->init_termios;
                }
 
                if (!*o_ltp_loc) {
-                       o_ltp = (struct ktermios *)
-                               kmalloc(sizeof(struct ktermios), GFP_KERNEL);
+                       o_ltp = kzalloc(sizeof(struct ktermios), GFP_KERNEL);
                        if (!o_ltp)
                                goto free_mem_out;
-                       memset(o_ltp, 0, sizeof(struct ktermios));
                }
 
                /*
                 * Everything allocated ... set up the o_tty structure.
                 */
-               if (!(driver->other->flags & TTY_DRIVER_DEVPTS_MEM)) {
+               if (!(driver->other->flags & TTY_DRIVER_DEVPTS_MEM))
                        driver->other->ttys[idx] = o_tty;
-               }
                if (!*o_tp_loc)
                        *o_tp_loc = o_tp;
                if (!*o_ltp_loc)
@@ -2011,15 +2172,14 @@ static int init_dev(struct tty_driver *driver, int idx,
                o_tty->link = tty;
        }
 
-       /* 
+       /*
         * All structures have been allocated, so now we install them.
         * Failures after this point use release_tty to clean up, so
         * there's no need to null out the local pointers.
         */
-       if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
+       if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM))
                driver->ttys[idx] = tty;
-       }
-       
+
        if (!*tp_loc)
                *tp_loc = tp;
        if (!*ltp_loc)
@@ -2032,7 +2192,7 @@ static int init_dev(struct tty_driver *driver, int idx,
        driver->refcount++;
        tty->count++;
 
-       /* 
+       /*
         * Structures all installed ... call the ldisc open routines.
         * If we fail here just call release_tty to clean up.  No need
         * to decrement the use counts, as release_tty doesn't care.
@@ -2069,7 +2229,7 @@ fast_track:
        if (driver->type == TTY_DRIVER_TYPE_PTY &&
            driver->subtype == PTY_TYPE_MASTER) {
                /*
-                * special case for PTY masters: only one open permitted, 
+                * special case for PTY masters: only one open permitted,
                 * and the slave side open count is incremented as well.
                 */
                if (tty->count) {
@@ -2082,11 +2242,11 @@ fast_track:
        tty->driver = driver; /* N.B. why do this every time?? */
 
        /* FIXME */
-       if(!test_bit(TTY_LDISC, &tty->flags))
+       if (!test_bit(TTY_LDISC, &tty->flags))
                printk(KERN_ERR "init_dev but no ldisc\n");
 success:
        *ret_tty = tty;
-       
+
        /* All paths come through here to release the mutex */
 end_init:
        return retval;
@@ -2188,7 +2348,7 @@ static void release_tty(struct tty_struct *tty, int idx)
  * WSH 09/09/97: rewritten to avoid some nasty race conditions that could
  * lead to double frees or releasing memory still in use.
  */
-static void release_dev(struct file * filp)
+static void release_dev(struct file *filp)
 {
        struct tty_struct *tty, *o_tty;
        int     pty_master, tty_closing, o_tty_closing, do_sleep;
@@ -2196,9 +2356,10 @@ static void release_dev(struct file * filp)
        int     idx;
        char    buf[64];
        unsigned long flags;
-       
+
        tty = (struct tty_struct *)filp->private_data;
-       if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "release_dev"))
+       if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode,
+                                                       "release_dev"))
                return;
 
        check_tty_count(tty, "release_dev");
@@ -2258,7 +2419,7 @@ static void release_dev(struct file * filp)
                               idx, tty->name);
                        return;
                }
-               if (o_tty->termios_locked != 
+               if (o_tty->termios_locked !=
                      tty->driver->other->termios_locked[idx]) {
                        printk(KERN_DEBUG "release_dev: other->termios_locked["
                                          "%d] not o_termios_locked for (%s)\n",
@@ -2294,7 +2455,7 @@ static void release_dev(struct file * filp)
        while (1) {
                /* Guard against races with tty->count changes elsewhere and
                   opens on /dev/tty */
-                  
+
                mutex_lock(&tty_mutex);
                tty_closing = tty->count <= 1;
                o_tty_closing = o_tty &&
@@ -2328,11 +2489,11 @@ static void release_dev(struct file * filp)
                                    "active!\n", tty_name(tty, buf));
                mutex_unlock(&tty_mutex);
                schedule();
-       }       
+       }
 
        /*
-        * The closing flags are now consistent with the open counts on 
-        * both sides, and we've completed the last operation that could 
+        * The closing flags are now consistent with the open counts on
+        * both sides, and we've completed the last operation that could
         * block, so it's safe to proceed with closing.
         */
        if (pty_master) {
@@ -2348,7 +2509,7 @@ static void release_dev(struct file * filp)
                       tty->count, tty_name(tty, buf));
                tty->count = 0;
        }
-       
+
        /*
         * We've decremented tty->count, so we need to remove this file
         * descriptor off the tty->tty_files list; this serves two
@@ -2368,9 +2529,9 @@ static void release_dev(struct file * filp)
         * case of a pty we may have to wait around for the other side
         * to close, and TTY_CLOSING makes sure we can't be reopened.
         */
-       if(tty_closing)
+       if (tty_closing)
                set_bit(TTY_CLOSING, &tty->flags);
-       if(o_tty_closing)
+       if (o_tty_closing)
                set_bit(TTY_CLOSING, &o_tty->flags);
 
        /*
@@ -2391,7 +2552,7 @@ static void release_dev(struct file * filp)
        /* check whether both sides are closing ... */
        if (!tty_closing || (o_tty && !o_tty_closing))
                return;
-       
+
 #ifdef TTY_DEBUG_HANGUP
        printk(KERN_DEBUG "freeing tty structure...");
 #endif
@@ -2406,17 +2567,16 @@ static void release_dev(struct file * filp)
        /*
         * Wait for ->hangup_work and ->buf.work handlers to terminate
         */
-        
+
        flush_scheduled_work();
-       
+
        /*
         * Wait for any short term users (we know they are just driver
         * side waiters as the file is closing so user count on the file
         * side is zero.
         */
        spin_lock_irqsave(&tty_ldisc_lock, flags);
-       while(tty->ldisc.refcount)
-       {
+       while (tty->ldisc.refcount) {
                spin_unlock_irqrestore(&tty_ldisc_lock, flags);
                wait_event(tty_ldisc_wait, tty->ldisc.refcount == 0);
                spin_lock_irqsave(&tty_ldisc_lock, flags);
@@ -2431,12 +2591,12 @@ static void release_dev(struct file * filp)
        if (tty->ldisc.close)
                (tty->ldisc.close)(tty);
        tty_ldisc_put(tty->ldisc.num);
-       
+
        /*
         *      Switch the line discipline back
         */
        tty_ldisc_assign(tty, tty_ldisc_get(N_TTY));
-       tty_set_termios_ldisc(tty,N_TTY); 
+       tty_set_termios_ldisc(tty, N_TTY);
        if (o_tty) {
                /* FIXME: could o_tty be in setldisc here ? */
                clear_bit(TTY_LDISC, &o_tty->flags);
@@ -2444,7 +2604,7 @@ static void release_dev(struct file * filp)
                        (o_tty->ldisc.close)(o_tty);
                tty_ldisc_put(o_tty->ldisc.num);
                tty_ldisc_assign(o_tty, tty_ldisc_get(N_TTY));
-               tty_set_termios_ldisc(o_tty,N_TTY); 
+               tty_set_termios_ldisc(o_tty, N_TTY);
        }
        /*
         * The release_tty function takes care of the details of clearing
@@ -2455,9 +2615,9 @@ static void release_dev(struct file * filp)
 #ifdef CONFIG_UNIX98_PTYS
        /* Make this pty number available for reallocation */
        if (devpts) {
-               down(&allocated_ptys_lock);
+               mutex_lock(&allocated_ptys_lock);
                idr_remove(&allocated_ptys, idx);
-               up(&allocated_ptys_lock);
+               mutex_unlock(&allocated_ptys_lock);
        }
 #endif
 
@@ -2484,7 +2644,7 @@ static void release_dev(struct file * filp)
  *              ->siglock protects ->signal/->sighand
  */
 
-static int tty_open(struct inode * inode, struct file * filp)
+static int tty_open(struct inode *inode, struct file *filp)
 {
        struct tty_struct *tty;
        int noctty, retval;
@@ -2492,18 +2652,17 @@ static int tty_open(struct inode * inode, struct file * filp)
        int index;
        dev_t device = inode->i_rdev;
        unsigned short saved_flags = filp->f_flags;
-       struct pid *old_pgrp;
 
        nonseekable_open(inode, filp);
-       
+
 retry_open:
        noctty = filp->f_flags & O_NOCTTY;
        index  = -1;
        retval = 0;
-       
+
        mutex_lock(&tty_mutex);
 
-       if (device == MKDEV(TTYAUX_MAJOR,0)) {
+       if (device == MKDEV(TTYAUX_MAJOR, 0)) {
                tty = get_current_tty();
                if (!tty) {
                        mutex_unlock(&tty_mutex);
@@ -2516,7 +2675,7 @@ retry_open:
                goto got_driver;
        }
 #ifdef CONFIG_VT
-       if (device == MKDEV(TTY_MAJOR,0)) {
+       if (device == MKDEV(TTY_MAJOR, 0)) {
                extern struct tty_driver *console_driver;
                driver = console_driver;
                index = fg_console;
@@ -2524,7 +2683,7 @@ retry_open:
                goto got_driver;
        }
 #endif
-       if (device == MKDEV(TTYAUX_MAJOR,1)) {
+       if (device == MKDEV(TTYAUX_MAJOR, 1)) {
                driver = console_device(&index);
                if (driver) {
                        /* Don't let /dev/console block */
@@ -2564,7 +2723,8 @@ got_driver:
        }
        filp->f_flags = saved_flags;
 
-       if (!retval && test_bit(TTY_EXCLUSIVE, &tty->flags) && !capable(CAP_SYS_ADMIN))
+       if (!retval && test_bit(TTY_EXCLUSIVE, &tty->flags) &&
+                                               !capable(CAP_SYS_ADMIN))
                retval = -EBUSY;
 
        if (retval) {
@@ -2586,17 +2746,16 @@ got_driver:
                goto retry_open;
        }
 
-       old_pgrp = NULL;
        mutex_lock(&tty_mutex);
        spin_lock_irq(&current->sighand->siglock);
        if (!noctty &&
            current->signal->leader &&
            !current->signal->tty &&
            tty->session == NULL)
-               old_pgrp = __proc_set_tty(current, tty);
+               __proc_set_tty(current, tty);
        spin_unlock_irq(&current->sighand->siglock);
        mutex_unlock(&tty_mutex);
-       put_pid(old_pgrp);
+       tty_audit_opening();
        return 0;
 }
 
@@ -2609,11 +2768,11 @@ got_driver:
  *     Allocate a unix98 pty master device from the ptmx driver.
  *
  *     Locking: tty_mutex protects theinit_dev work. tty->count should
              protect the rest.
*             protect the rest.
  *             allocated_ptys_lock handles the list of free pty numbers
  */
 
-static int ptmx_open(struct inode * inode, struct file * filp)
+static int ptmx_open(struct inode *inode, struct file *filp)
 {
        struct tty_struct *tty;
        int retval;
@@ -2623,29 +2782,29 @@ static int ptmx_open(struct inode * inode, struct file * filp)
        nonseekable_open(inode, filp);
 
        /* find a device that is not in use. */
-       down(&allocated_ptys_lock);
+       mutex_lock(&allocated_ptys_lock);
        if (!idr_pre_get(&allocated_ptys, GFP_KERNEL)) {
-               up(&allocated_ptys_lock);
+               mutex_unlock(&allocated_ptys_lock);
                return -ENOMEM;
        }
        idr_ret = idr_get_new(&allocated_ptys, NULL, &index);
        if (idr_ret < 0) {
-               up(&allocated_ptys_lock);
+               mutex_unlock(&allocated_ptys_lock);
                if (idr_ret == -EAGAIN)
                        return -ENOMEM;
                return -EIO;
        }
        if (index >= pty_limit) {
                idr_remove(&allocated_ptys, index);
-               up(&allocated_ptys_lock);
+               mutex_unlock(&allocated_ptys_lock);
                return -EIO;
        }
-       up(&allocated_ptys_lock);
+       mutex_unlock(&allocated_ptys_lock);
 
        mutex_lock(&tty_mutex);
        retval = init_dev(ptm_driver, index, &tty);
        mutex_unlock(&tty_mutex);
-       
+
        if (retval)
                goto out;
 
@@ -2659,15 +2818,17 @@ static int ptmx_open(struct inode * inode, struct file * filp)
 
        check_tty_count(tty, "tty_open");
        retval = ptm_driver->open(tty, filp);
-       if (!retval)
+       if (!retval) {
+               tty_audit_opening();
                return 0;
+       }
 out1:
        release_dev(filp);
        return retval;
 out:
-       down(&allocated_ptys_lock);
+       mutex_lock(&allocated_ptys_lock);
        idr_remove(&allocated_ptys, index);
-       up(&allocated_ptys_lock);
+       mutex_unlock(&allocated_ptys_lock);
        return retval;
 }
 #endif
@@ -2684,7 +2845,7 @@ out:
  *             Takes bkl. See release_dev
  */
 
-static int tty_release(struct inode * inode, struct file * filp)
+static int tty_release(struct inode *inode, struct file *filp)
 {
        lock_kernel();
        release_dev(filp);
@@ -2704,16 +2865,16 @@ static int tty_release(struct inode * inode, struct file * filp)
  *     may be re-entered freely by other callers.
  */
 
-static unsigned int tty_poll(struct file * filp, poll_table * wait)
+static unsigned int tty_poll(struct file *filp, poll_table *wait)
 {
-       struct tty_struct * tty;
+       struct tty_struct *tty;
        struct tty_ldisc *ld;
        int ret = 0;
 
        tty = (struct tty_struct *)filp->private_data;
        if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_poll"))
                return 0;
-               
+
        ld = tty_ldisc_ref_wait(tty);
        if (ld->poll)
                ret = (ld->poll)(tty, filp, wait);
@@ -2721,15 +2882,15 @@ static unsigned int tty_poll(struct file * filp, poll_table * wait)
        return ret;
 }
 
-static int tty_fasync(int fd, struct file * filp, int on)
+static int tty_fasync(int fd, struct file *filp, int on)
 {
-       struct tty_struct * tty;
+       struct tty_struct *tty;
        int retval;
 
        tty = (struct tty_struct *)filp->private_data;
        if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode, "tty_fasync"))
                return 0;
-       
+
        retval = fasync_helper(fd, filp, on, &tty->fasync);
        if (retval <= 0)
                return retval;
@@ -2761,7 +2922,7 @@ static int tty_fasync(int fd, struct file * filp, int on)
  *     @tty: tty to fake input into
  *     @p: pointer to character
  *
- *     Fake input to a tty device. Does the neccessary locking and
+ *     Fake input to a tty device. Does the necessary locking and
  *     input management.
  *
  *     FIXME: does not honour flow control ??
@@ -2777,7 +2938,7 @@ static int tiocsti(struct tty_struct *tty, char __user *p)
 {
        char ch, mbz = 0;
        struct tty_ldisc *ld;
-       
+
        if ((current->signal->tty != tty) && !capable(CAP_SYS_ADMIN))
                return -EPERM;
        if (get_user(ch, p))
@@ -2799,7 +2960,7 @@ static int tiocsti(struct tty_struct *tty, char __user *p)
  *             is consistent.
  */
 
-static int tiocgwinsz(struct tty_struct *tty, struct winsize __user * arg)
+static int tiocgwinsz(struct tty_struct *tty, struct winsize __user *arg)
 {
        int err;
 
@@ -2828,7 +2989,7 @@ static int tiocgwinsz(struct tty_struct *tty, struct winsize __user * arg)
  */
 
 static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,
-       struct winsize __user * arg)
+       struct winsize __user *arg)
 {
        struct winsize tmp_ws;
 
@@ -2844,7 +3005,7 @@ static int tiocswinsz(struct tty_struct *tty, struct tty_struct *real_tty,
                if (vc_lock_resize(tty->driver_data, tmp_ws.ws_col,
                                        tmp_ws.ws_row)) {
                        mutex_unlock(&tty->termios_mutex);
-                       return -ENXIO;
+                       return -ENXIO;
                }
        }
 #endif
@@ -2954,7 +3115,7 @@ static int tiocsctty(struct tty_struct *tty, int arg)
                 * This tty is already the controlling
                 * tty for another session group!
                 */
-               if ((arg == 1) && capable(CAP_SYS_ADMIN)) {
+               if (arg == 1 && capable(CAP_SYS_ADMIN)) {
                        /*
                         * Steal it away
                         */
@@ -2992,7 +3153,7 @@ static int tiocgpgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
         */
        if (tty == real_tty && current->signal->tty != real_tty)
                return -ENOTTY;
-       return put_user(pid_nr(real_tty->pgrp), p);
+       return put_user(pid_vnr(real_tty->pgrp), p);
 }
 
 /**
@@ -3026,7 +3187,7 @@ static int tiocspgrp(struct tty_struct *tty, struct tty_struct *real_tty, pid_t
        if (pgrp_nr < 0)
                return -EINVAL;
        rcu_read_lock();
-       pgrp = find_pid(pgrp_nr);
+       pgrp = find_vpid(pgrp_nr);
        retval = -ESRCH;
        if (!pgrp)
                goto out_unlock;
@@ -3063,7 +3224,7 @@ static int tiocgsid(struct tty_struct *tty, struct tty_struct *real_tty, pid_t _
                return -ENOTTY;
        if (!real_tty->session)
                return -ENOTTY;
-       return put_user(pid_nr(real_tty->session), p);
+       return put_user(pid_vnr(real_tty->session), p);
 }
 
 /**
@@ -3100,14 +3261,13 @@ static int tiocsetd(struct tty_struct *tty, int __user *p)
 
 static int send_break(struct tty_struct *tty, unsigned int duration)
 {
-       if (mutex_lock_interruptible(&tty->atomic_write_lock))
+       if (tty_write_lock(tty, 0) < 0)
                return -EINTR;
        tty->driver->break_ctl(tty, -1);
-       if (!signal_pending(current)) {
+       if (!signal_pending(current))
                msleep_interruptible(duration);
-       }
        tty->driver->break_ctl(tty, 0);
-       mutex_unlock(&tty->atomic_write_lock);
+       tty_write_unlock(tty);
        if (signal_pending(current))
                return -EINTR;
        return 0;
@@ -3188,14 +3348,14 @@ static int tty_tiocmset(struct tty_struct *tty, struct file *file, unsigned int
 /*
  * Split this up, as gcc can choke on it otherwise..
  */
-int tty_ioctl(struct inode * inode, struct file * file,
+int tty_ioctl(struct inode *inode, struct file *file,
              unsigned int cmd, unsigned long arg)
 {
        struct tty_struct *tty, *real_tty;
        void __user *p = (void __user *)arg;
        int retval;
        struct tty_ldisc *ld;
-       
+
        tty = (struct tty_struct *)file->private_data;
        if (tty_paranoia_check(tty, inode, "tty_ioctl"))
                return -EINVAL;
@@ -3211,13 +3371,13 @@ int tty_ioctl(struct inode * inode, struct file * file,
         * Break handling by driver
         */
        if (!tty->driver->break_ctl) {
-               switch(cmd) {
+               switch (cmd) {
                case TIOCSBRK:
                case TIOCCBRK:
                        if (tty->driver->ioctl)
                                return tty->driver->ioctl(tty, file, cmd, arg);
                        return -EINVAL;
-                       
+
                /* These two ioctl's always return success; even if */
                /* the driver doesn't support them. */
                case TCSBRK:
@@ -3239,7 +3399,7 @@ int tty_ioctl(struct inode * inode, struct file * file,
        case TIOCSBRK:
        case TIOCCBRK:
        case TCSBRK:
-       case TCSBRKP:                   
+       case TCSBRKP:
                retval = tty_check_change(tty);
                if (retval)
                        return retval;
@@ -3252,74 +3412,80 @@ int tty_ioctl(struct inode * inode, struct file * file,
        }
 
        switch (cmd) {
-               case TIOCSTI:
-                       return tiocsti(tty, p);
-               case TIOCGWINSZ:
-                       return tiocgwinsz(tty, p);
-               case TIOCSWINSZ:
-                       return tiocswinsz(tty, real_tty, p);
-               case TIOCCONS:
-                       return real_tty!=tty ? -EINVAL : tioccons(file);
-               case FIONBIO:
-                       return fionbio(file, p);
-               case TIOCEXCL:
-                       set_bit(TTY_EXCLUSIVE, &tty->flags);
-                       return 0;
-               case TIOCNXCL:
-                       clear_bit(TTY_EXCLUSIVE, &tty->flags);
-                       return 0;
-               case TIOCNOTTY:
-                       if (current->signal->tty != tty)
-                               return -ENOTTY;
-                       if (current->signal->leader)
-                               disassociate_ctty(0);
-                       proc_clear_tty(current);
-                       return 0;
-               case TIOCSCTTY:
-                       return tiocsctty(tty, arg);
-               case TIOCGPGRP:
-                       return tiocgpgrp(tty, real_tty, p);
-               case TIOCSPGRP:
-                       return tiocspgrp(tty, real_tty, p);
-               case TIOCGSID:
-                       return tiocgsid(tty, real_tty, p);
-               case TIOCGETD:
-                       /* FIXME: check this is ok */
-                       return put_user(tty->ldisc.num, (int __user *)p);
-               case TIOCSETD:
-                       return tiocsetd(tty, p);
+       case TIOCSTI:
+               return tiocsti(tty, p);
+       case TIOCGWINSZ:
+               return tiocgwinsz(tty, p);
+       case TIOCSWINSZ:
+               return tiocswinsz(tty, real_tty, p);
+       case TIOCCONS:
+               return real_tty != tty ? -EINVAL : tioccons(file);
+       case FIONBIO:
+               return fionbio(file, p);
+       case TIOCEXCL:
+               set_bit(TTY_EXCLUSIVE, &tty->flags);
+               return 0;
+       case TIOCNXCL:
+               clear_bit(TTY_EXCLUSIVE, &tty->flags);
+               return 0;
+       case TIOCNOTTY:
+               if (current->signal->tty != tty)
+                       return -ENOTTY;
+               no_tty();
+               return 0;
+       case TIOCSCTTY:
+               return tiocsctty(tty, arg);
+       case TIOCGPGRP:
+               return tiocgpgrp(tty, real_tty, p);
+       case TIOCSPGRP:
+               return tiocspgrp(tty, real_tty, p);
+       case TIOCGSID:
+               return tiocgsid(tty, real_tty, p);
+       case TIOCGETD:
+               /* FIXME: check this is ok */
+               return put_user(tty->ldisc.num, (int __user *)p);
+       case TIOCSETD:
+               return tiocsetd(tty, p);
 #ifdef CONFIG_VT
-               case TIOCLINUX:
-                       return tioclinux(tty, arg);
+       case TIOCLINUX:
+               return tioclinux(tty, arg);
 #endif
-               /*
-                * Break handling
-                */
-               case TIOCSBRK:  /* Turn break on, unconditionally */
-                       tty->driver->break_ctl(tty, -1);
-                       return 0;
-                       
-               case TIOCCBRK:  /* Turn break off, unconditionally */
-                       tty->driver->break_ctl(tty, 0);
-                       return 0;
-               case TCSBRK:   /* SVID version: non-zero arg --> no break */
-                       /* non-zero arg means wait for all output data
-                        * to be sent (performed above) but don't send break.
-                        * This is used by the tcdrain() termios function.
-                        */
-                       if (!arg)
-                               return send_break(tty, 250);
-                       return 0;
-               case TCSBRKP:   /* support for POSIX tcsendbreak() */   
-                       return send_break(tty, arg ? arg*100 : 250);
-
-               case TIOCMGET:
-                       return tty_tiocmget(tty, file, p);
+       /*
+        * Break handling
+        */
+       case TIOCSBRK:  /* Turn break on, unconditionally */
+               tty->driver->break_ctl(tty, -1);
+               return 0;
 
-               case TIOCMSET:
-               case TIOCMBIC:
-               case TIOCMBIS:
-                       return tty_tiocmset(tty, file, cmd, p);
+       case TIOCCBRK:  /* Turn break off, unconditionally */
+               tty->driver->break_ctl(tty, 0);
+               return 0;
+       case TCSBRK:   /* SVID version: non-zero arg --> no break */
+               /* non-zero arg means wait for all output data
+                * to be sent (performed above) but don't send break.
+                * This is used by the tcdrain() termios function.
+                */
+               if (!arg)
+                       return send_break(tty, 250);
+               return 0;
+       case TCSBRKP:   /* support for POSIX tcsendbreak() */
+               return send_break(tty, arg ? arg*100 : 250);
+
+       case TIOCMGET:
+               return tty_tiocmget(tty, file, p);
+       case TIOCMSET:
+       case TIOCMBIC:
+       case TIOCMBIS:
+               return tty_tiocmset(tty, file, cmd, p);
+       case TCFLSH:
+               switch (arg) {
+               case TCIFLUSH:
+               case TCIOFLUSH:
+               /* flush tty buffer and allow ldisc to process ioctl */
+                       tty_buffer_flush(tty);
+                       break;
+               }
+               break;
        }
        if (tty->driver->ioctl) {
                retval = (tty->driver->ioctl)(tty, file, cmd, arg);
@@ -3337,13 +3503,39 @@ int tty_ioctl(struct inode * inode, struct file * file,
        return retval;
 }
 
+#ifdef CONFIG_COMPAT
+static long tty_compat_ioctl(struct file *file, unsigned int cmd,
+                               unsigned long arg)
+{
+       struct inode *inode = file->f_dentry->d_inode;
+       struct tty_struct *tty = file->private_data;
+       struct tty_ldisc *ld;
+       int retval = -ENOIOCTLCMD;
+
+       if (tty_paranoia_check(tty, inode, "tty_ioctl"))
+               return -EINVAL;
+
+       if (tty->driver->compat_ioctl) {
+               retval = (tty->driver->compat_ioctl)(tty, file, cmd, arg);
+               if (retval != -ENOIOCTLCMD)
+                       return retval;
+       }
+
+       ld = tty_ldisc_ref_wait(tty);
+       if (ld->compat_ioctl)
+               retval = ld->compat_ioctl(tty, file, cmd, arg);
+       tty_ldisc_deref(ld);
+
+       return retval;
+}
+#endif
 
 /*
  * This implements the "Secure Attention Key" ---  the idea is to
  * prevent trojan horses by killing all processes associated with this
  * tty when the user hits the "Secure Attention Key".  Required for
  * super-paranoid applications --- see the Orange Book for more details.
- * 
+ *
  * This code could be nicer; ideally it should send a HUP, wait a few
  * seconds, then send a INT, and then a KILL signal.  But you then
  * have to coordinate with the init process, since all processes associated
@@ -3367,22 +3559,22 @@ void __do_SAK(struct tty_struct *tty)
        int             i;
        struct file     *filp;
        struct fdtable *fdt;
-       
+
        if (!tty)
                return;
        session = tty->session;
-       
+
        tty_ldisc_flush(tty);
 
        if (tty->driver->flush_buffer)
                tty->driver->flush_buffer(tty);
-       
+
        read_lock(&tasklist_lock);
        /* Kill the entire session */
        do_each_pid_task(session, PIDTYPE_SID, p) {
                printk(KERN_NOTICE "SAK: killed process %d"
-                       " (%s): process_session(p)==tty->session\n",
-                       p->pid, p->comm);
+                       " (%s): task_session_nr(p)==tty->session\n",
+                       task_pid_nr(p), p->comm);
                send_sig(SIGKILL, p, 1);
        } while_each_pid_task(session, PIDTYPE_SID, p);
        /* Now kill any processes that happen to have the
@@ -3391,8 +3583,8 @@ void __do_SAK(struct tty_struct *tty)
        do_each_thread(g, p) {
                if (p->signal->tty == tty) {
                        printk(KERN_NOTICE "SAK: killed process %d"
-                           " (%s): process_session(p)==tty->session\n",
-                           p->pid, p->comm);
+                           " (%s): task_session_nr(p)==tty->session\n",
+                           task_pid_nr(p), p->comm);
                        send_sig(SIGKILL, p, 1);
                        continue;
                }
@@ -3404,7 +3596,7 @@ void __do_SAK(struct tty_struct *tty)
                         */
                        spin_lock(&p->files->file_lock);
                        fdt = files_fdtable(p->files);
-                       for (i=0; i < fdt->max_fds; i++) {
+                       for (i = 0; i < fdt->max_fds; i++) {
                                filp = fcheck_files(p->files, i);
                                if (!filp)
                                        continue;
@@ -3412,7 +3604,7 @@ void __do_SAK(struct tty_struct *tty)
                                    filp->private_data == tty) {
                                        printk(KERN_NOTICE "SAK: killed process %d"
                                            " (%s): fd#%d opened to the tty\n",
-                                           p->pid, p->comm, i);
+                                           task_pid_nr(p), p->comm, i);
                                        force_sig(SIGKILL, p);
                                        break;
                                }
@@ -3458,7 +3650,7 @@ EXPORT_SYMBOL(do_SAK);
  *     while invoking the line discipline receive_buf method. The
  *     receive_buf method is single threaded for each tty instance.
  */
+
 static void flush_to_ldisc(struct work_struct *work)
 {
        struct tty_struct *tty =
@@ -3474,6 +3666,8 @@ static void flush_to_ldisc(struct work_struct *work)
                return;
 
        spin_lock_irqsave(&tty->buf.lock, flags);
+       /* So we know a flush is running */
+       set_bit(TTY_FLUSHING, &tty->flags);
        head = tty->buf.head;
        if (head != NULL) {
                tty->buf.head = NULL;
@@ -3487,6 +3681,11 @@ static void flush_to_ldisc(struct work_struct *work)
                                tty_buffer_free(tty, tbuf);
                                continue;
                        }
+                       /* Ldisc or user is trying to flush the buffers
+                          we are feeding to the ldisc, stop feeding the
+                          line discipline as we want to empty the queue */
+                       if (test_bit(TTY_FLUSHPENDING, &tty->flags))
+                               break;
                        if (!tty->receive_room) {
                                schedule_delayed_work(&tty->buf.work, 1);
                                break;
@@ -3500,8 +3699,17 @@ static void flush_to_ldisc(struct work_struct *work)
                        disc->receive_buf(tty, char_buf, flag_buf, count);
                        spin_lock_irqsave(&tty->buf.lock, flags);
                }
+               /* Restore the queue head */
                tty->buf.head = head;
        }
+       /* We may have a deferred request to flush the input buffer,
+          if so pull the chain under the lock and empty the queue */
+       if (test_bit(TTY_FLUSHPENDING, &tty->flags)) {
+               __tty_buffer_flush(tty);
+               clear_bit(TTY_FLUSHPENDING, &tty->flags);
+               wake_up(&tty->read_wait);
+       }
+       clear_bit(TTY_FLUSHING, &tty->flags);
        spin_unlock_irqrestore(&tty->buf.lock, flags);
 
        tty_ldisc_deref(disc);
@@ -3558,7 +3766,6 @@ static void initialize_tty_struct(struct tty_struct *tty)
        tty->buf.head = tty->buf.tail = NULL;
        tty_buffer_init(tty);
        INIT_DELAYED_WORK(&tty->buf.work, flush_to_ldisc);
-       init_MUTEX(&tty->buf.pty_sem);
        mutex_init(&tty->termios_mutex);
        init_waitqueue_head(&tty->write_wait);
        init_waitqueue_head(&tty->read_wait);
@@ -3633,7 +3840,8 @@ struct device *tty_register_device(struct tty_driver *driver, unsigned index,
 
 void tty_unregister_device(struct tty_driver *driver, unsigned index)
 {
-       device_destroy(tty_class, MKDEV(driver->major, driver->minor_start) + index);
+       device_destroy(tty_class,
+               MKDEV(driver->major, driver->minor_start) + index);
 }
 
 EXPORT_SYMBOL(tty_register_device);
@@ -3643,9 +3851,8 @@ struct tty_driver *alloc_tty_driver(int lines)
 {
        struct tty_driver *driver;
 
-       driver = kmalloc(sizeof(struct tty_driver), GFP_KERNEL);
+       driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL);
        if (driver) {
-               memset(driver, 0, sizeof(struct tty_driver));
                driver->magic = TTY_DRIVER_MAGIC;
                driver->num = lines;
                /* later we'll move allocation of tables here */
@@ -3669,6 +3876,7 @@ void tty_set_operations(struct tty_driver *driver,
        driver->write_room = op->write_room;
        driver->chars_in_buffer = op->chars_in_buffer;
        driver->ioctl = op->ioctl;
+       driver->compat_ioctl = op->compat_ioctl;
        driver->set_termios = op->set_termios;
        driver->throttle = op->throttle;
        driver->unthrottle = op->unthrottle;
@@ -3684,6 +3892,11 @@ void tty_set_operations(struct tty_driver *driver,
        driver->write_proc = op->write_proc;
        driver->tiocmget = op->tiocmget;
        driver->tiocmset = op->tiocmset;
+#ifdef CONFIG_CONSOLE_POLL
+       driver->poll_init = op->poll_init;
+       driver->poll_get_char = op->poll_get_char;
+       driver->poll_put_char = op->poll_put_char;
+#endif
 }
 
 
@@ -3697,31 +3910,29 @@ EXPORT_SYMBOL(tty_set_operations);
 int tty_register_driver(struct tty_driver *driver)
 {
        int error;
-        int i;
+       int i;
        dev_t dev;
        void **p = NULL;
 
        if (driver->flags & TTY_DRIVER_INSTALLED)
                return 0;
 
-       if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
-               p = kmalloc(driver->num * 3 * sizeof(void *), GFP_KERNEL);
+       if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM) && driver->num) {
+               p = kzalloc(driver->num * 3 * sizeof(void *), GFP_KERNEL);
                if (!p)
                        return -ENOMEM;
-               memset(p, 0, driver->num * 3 * sizeof(void *));
        }
 
        if (!driver->major) {
-               error = alloc_chrdev_region(&dev, driver->minor_start, driver->num,
-                                               (char*)driver->name);
+               error = alloc_chrdev_region(&dev, driver->minor_start,
+                                               driver->num, driver->name);
                if (!error) {
                        driver->major = MAJOR(dev);
                        driver->minor_start = MINOR(dev);
                }
        } else {
                dev = MKDEV(driver->major, driver->minor_start);
-               error = register_chrdev_region(dev, driver->num,
-                                               (char*)driver->name);
+               error = register_chrdev_region(dev, driver->num, driver->name);
        }
        if (error < 0) {
                kfree(p);
@@ -3731,7 +3942,8 @@ int tty_register_driver(struct tty_driver *driver)
        if (p) {
                driver->ttys = (struct tty_struct **)p;
                driver->termios = (struct ktermios **)(p + driver->num);
-               driver->termios_locked = (struct ktermios **)(p + driver->num * 2);
+               driver->termios_locked = (struct ktermios **)
+                                                       (p + driver->num * 2);
        } else {
                driver->ttys = NULL;
                driver->termios = NULL;
@@ -3751,11 +3963,13 @@ int tty_register_driver(struct tty_driver *driver)
 
        if (!driver->put_char)
                driver->put_char = tty_default_put_char;
-       
+
+       mutex_lock(&tty_mutex);
        list_add(&driver->tty_drivers, &tty_drivers);
-       
-       if ( !(driver->flags & TTY_DRIVER_DYNAMIC_DEV) ) {
-               for(i = 0; i < driver->num; i++)
+       mutex_unlock(&tty_mutex);
+
+       if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV)) {
+               for (i = 0; i < driver->num; i++)
                    tty_register_device(driver, i, NULL);
        }
        proc_tty_register_driver(driver);
@@ -3778,8 +3992,9 @@ int tty_unregister_driver(struct tty_driver *driver)
 
        unregister_chrdev_region(MKDEV(driver->major, driver->minor_start),
                                driver->num);
-
+       mutex_lock(&tty_mutex);
        list_del(&driver->tty_drivers);
+       mutex_unlock(&tty_mutex);
 
        /*
         * Free the termios and termios_locked structures because
@@ -3824,28 +4039,25 @@ void proc_clear_tty(struct task_struct *p)
 }
 EXPORT_SYMBOL(proc_clear_tty);
 
-static struct pid *__proc_set_tty(struct task_struct *tsk, struct tty_struct *tty)
+static void __proc_set_tty(struct task_struct *tsk, struct tty_struct *tty)
 {
-       struct pid *old_pgrp;
        if (tty) {
+               /* We should not have a session or pgrp to here but.... */
+               put_pid(tty->session);
+               put_pid(tty->pgrp);
                tty->session = get_pid(task_session(tsk));
                tty->pgrp = get_pid(task_pgrp(tsk));
        }
-       old_pgrp = tsk->signal->tty_old_pgrp;
+       put_pid(tsk->signal->tty_old_pgrp);
        tsk->signal->tty = tty;
        tsk->signal->tty_old_pgrp = NULL;
-       return old_pgrp;
 }
 
-void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty)
+static void proc_set_tty(struct task_struct *tsk, struct tty_struct *tty)
 {
-       struct pid *old_pgrp;
-
        spin_lock_irq(&tsk->sighand->siglock);
-       old_pgrp = __proc_set_tty(tsk, tty);
+       __proc_set_tty(tsk, tty);
        spin_unlock_irq(&tsk->sighand->siglock);
-
-       put_pid(old_pgrp);
 }
 
 struct tty_struct *get_current_tty(void)
@@ -3877,12 +4089,9 @@ void __init console_init(void)
        (void) tty_register_ldisc(N_TTY, &tty_ldisc_N_TTY);
 
        /*
-        * set up the console device so that later boot sequences can 
+        * set up the console device so that later boot sequences can
         * inform about problems etc..
         */
-#ifdef CONFIG_EARLY_PRINTK
-       disable_early_printk();
-#endif
        call = __con_initcall_start;
        while (call < __con_initcall_end) {
                (*call)();
@@ -3890,10 +4099,6 @@ void __init console_init(void)
        }
 }
 
-#ifdef CONFIG_VT
-extern int vty_init(void);
-#endif
-
 static int __init tty_class_init(void)
 {
        tty_class = class_create(THIS_MODULE, "tty");