vserver 1.9.5.x5

[linux-2.6.git] / drivers / char / pty.c

diff --git a/drivers/char/pty.c b/drivers/char/pty.c
index 9826bbd..da32889 100644 (file)
--- a/drivers/char/pty.c
+++ b/drivers/char/pty.c
@@ -29,13 +29,13 @@
 
 #include <asm/uaccess.h>
 #include <asm/system.h>
-#include <asm/bitops.h>
+#include <linux/bitops.h>
 #include <linux/devpts_fs.h>
 
 /* These are global because they are accessed in tty_io.c */
 #ifdef CONFIG_UNIX98_PTYS
 struct tty_driver *ptm_driver;
-struct tty_driver *pts_driver;
+static struct tty_driver *pts_driver;
 #endif
 
 static void pty_close(struct tty_struct * tty, struct file * filp)
@@ -55,9 +55,9 @@ static void pty_close(struct tty_struct * tty, struct file * filp)
        if (!tty->link)
                return;
        tty->link->packet = 0;
+       set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
        wake_up_interruptible(&tty->link->read_wait);
        wake_up_interruptible(&tty->link->write_wait);
-       set_bit(TTY_OTHER_CLOSED, &tty->link->flags);
        if (tty->driver->subtype == PTY_TYPE_MASTER) {
                set_bit(TTY_OTHER_CLOSED, &tty->flags);
 #ifdef CONFIG_UNIX98_PTYS
@@ -103,51 +103,18 @@ static void pty_unthrottle(struct tty_struct * tty)
  * not our partners. We can't just take the other one blindly without
  * risking deadlocks.  There is also the small matter of TTY_DONT_FLIP
  */
-static int pty_write(struct tty_struct * tty, int from_user,
-                      const unsigned char *buf, int count)
+static int pty_write(struct tty_struct * tty, const unsigned char *buf, int count)
 {
        struct tty_struct *to = tty->link;
-       int     c=0, n, room;
-       char    *temp_buffer;
+       int     c;
 
        if (!to || tty->stopped)
                return 0;
 
-       if (from_user) {
-               down(&tty->flip.pty_sem);
-               temp_buffer = &tty->flip.char_buf[0];
-               while (count > 0) {
-                       /* check space so we don't copy needlessly */ 
-                       n = to->ldisc.receive_room(to);
-                       if (n > count)
-                               n = count;
-                       if (!n) break;
-
-                       n  = min(n, PTY_BUF_SIZE);
-                       n -= copy_from_user(temp_buffer, buf, n);
-                       if (!n) {
-                               if (!c)
-                                       c = -EFAULT;
-                               break;
-                       }
-
-                       /* check again in case the buffer filled up */
-                       room = to->ldisc.receive_room(to);
-                       if (n > room)
-                               n = room;
-                       if (!n) break;
-                       buf   += n; 
-                       c     += n;
-                       count -= n;
-                       to->ldisc.receive_buf(to, temp_buffer, NULL, n);
-               }
-               up(&tty->flip.pty_sem);
-       } else {
-               c = to->ldisc.receive_room(to);
-               if (c > count)
-                       c = count;
-               to->ldisc.receive_buf(to, buf, NULL, c);
-       }
+       c = to->ldisc.receive_room(to);
+       if (c > count)
+               c = count;
+       to->ldisc.receive_buf(to, buf, NULL, c);
        
        return c;
 }
@@ -182,13 +149,15 @@ static int pty_write_room(struct tty_struct *tty)
 static int pty_chars_in_buffer(struct tty_struct *tty)
 {
        struct tty_struct *to = tty->link;
+       ssize_t (*chars_in_buffer)(struct tty_struct *);
        int count;
 
-       if (!to || !to->ldisc.chars_in_buffer)
+       /* We should get the line discipline lock for "tty->link" */
+       if (!to || !(chars_in_buffer = to->ldisc.chars_in_buffer))
                return 0;
 
        /* The ldisc must report 0 if no characters available to be read */
-       count = to->ldisc.chars_in_buffer(to);
+       count = chars_in_buffer(to);
 
        if (tty->driver->subtype == PTY_TYPE_SLAVE) return count;