tty: some ICANON magic is in the wrong places
Alan Cox [Mon, 13 Oct 2008 09:44:17 +0000 (10:44 +0100)]
Move the set up on ldisc change into the ldisc
Move the INQ/OUTQ cases into the driver not in shared ioctl code where it
gives bogus answers for other ldisc values

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/bluetooth/hci_ldisc.c
drivers/char/n_hdlc.c
drivers/char/n_tty.c
drivers/char/tty_ioctl.c
include/linux/tty.h

index 8dfcf77..4426bb5 100644 (file)
@@ -484,7 +484,7 @@ static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file * file,
                return -EUNATCH;
 
        default:
-               err = n_tty_ioctl(tty, file, cmd, arg);
+               err = n_tty_ioctl_helper(tty, file, cmd, arg);
                break;
        };
 
index 69ec639..bacb3e2 100644 (file)
@@ -764,7 +764,7 @@ static int n_hdlc_tty_ioctl(struct tty_struct *tty, struct file *file,
                break;
 
        default:
-               error = n_tty_ioctl (tty, file, cmd, arg);
+               error = n_tty_ioctl_helper(tty, file, cmd, arg);
                break;
        }
        return error;
index 708c2b1..b4f5dcc 100644 (file)
@@ -1011,8 +1011,20 @@ int is_ignored(int sig)
 
 static void n_tty_set_termios(struct tty_struct *tty, struct ktermios *old)
 {
-       if (!tty)
-               return;
+       int canon_change = 1;
+       BUG_ON(!tty);
+
+       if (old)
+               canon_change = (old->c_lflag ^ tty->termios->c_lflag) & ICANON;
+       if (canon_change) {
+               memset(&tty->read_flags, 0, sizeof tty->read_flags);
+               tty->canon_head = tty->read_tail;
+               tty->canon_data = 0;
+               tty->erasing = 0;
+       }
+
+       if (canon_change && !L_ICANON(tty) && tty->read_cnt)
+               wake_up_interruptible(&tty->read_wait);
 
        tty->icanon = (L_ICANON(tty) != 0);
        if (test_bit(TTY_HW_COOK_IN, &tty->flags)) {
@@ -1573,6 +1585,43 @@ static unsigned int normal_poll(struct tty_struct *tty, struct file *file,
        return mask;
 }
 
+static unsigned long inq_canon(struct tty_struct *tty)
+{
+       int nr, head, tail;
+
+       if (!tty->canon_data || !tty->read_buf)
+               return 0;
+       head = tty->canon_head;
+       tail = tty->read_tail;
+       nr = (head - tail) & (N_TTY_BUF_SIZE-1);
+       /* Skip EOF-chars.. */
+       while (head != tail) {
+               if (test_bit(tail, tty->read_flags) &&
+                   tty->read_buf[tail] == __DISABLED_CHAR)
+                       nr--;
+               tail = (tail+1) & (N_TTY_BUF_SIZE-1);
+       }
+       return nr;
+}
+
+static int n_tty_ioctl(struct tty_struct *tty, struct file *file,
+                      unsigned int cmd, unsigned long arg)
+{
+       int retval;
+
+       switch (cmd) {
+       case TIOCOUTQ:
+               return put_user(tty_chars_in_buffer(tty), (int __user *) arg);
+       case TIOCINQ:
+               retval = tty->read_cnt;
+               if (L_ICANON(tty))
+                       retval = inq_canon(tty);
+               return put_user(retval, (unsigned int __user *) arg);
+       default:
+               return n_tty_ioctl_helper(tty, file, cmd, arg);
+       }
+}
+
 struct tty_ldisc_ops tty_ldisc_N_TTY = {
        .magic           = TTY_LDISC_MAGIC,
        .name            = "n_tty",
index 14cc19c..a408c8e 100644 (file)
@@ -489,7 +489,6 @@ EXPORT_SYMBOL(tty_termios_hw_change);
 
 static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
 {
-       int canon_change;
        struct ktermios old_termios;
        struct tty_ldisc *ld;
        unsigned long flags;
@@ -505,18 +504,6 @@ static void change_termios(struct tty_struct *tty, struct ktermios *new_termios)
        old_termios = *tty->termios;
        *tty->termios = *new_termios;
        unset_locked_termios(tty->termios, &old_termios, tty->termios_locked);
-       canon_change = (old_termios.c_lflag ^ tty->termios->c_lflag) & ICANON;
-       if (canon_change) {
-               memset(&tty->read_flags, 0, sizeof tty->read_flags);
-               tty->canon_head = tty->read_tail;
-               tty->canon_data = 0;
-               tty->erasing = 0;
-       }
-
-       /* This bit should be in the ldisc code */
-       if (canon_change && !L_ICANON(tty) && tty->read_cnt)
-               /* Get characters left over from canonical mode. */
-               wake_up_interruptible(&tty->read_wait);
 
        /* See if packet mode change of state. */
        if (tty->link && tty->link->packet) {
@@ -677,24 +664,6 @@ static int set_termiox(struct tty_struct *tty, void __user *arg, int opt)
 
 #endif
 
-static unsigned long inq_canon(struct tty_struct *tty)
-{
-       int nr, head, tail;
-
-       if (!tty->canon_data || !tty->read_buf)
-               return 0;
-       head = tty->canon_head;
-       tail = tty->read_tail;
-       nr = (head - tail) & (N_TTY_BUF_SIZE-1);
-       /* Skip EOF-chars.. */
-       while (head != tail) {
-               if (test_bit(tail, tty->read_flags) &&
-                   tty->read_buf[tail] == __DISABLED_CHAR)
-                       nr--;
-               tail = (tail+1) & (N_TTY_BUF_SIZE-1);
-       }
-       return nr;
-}
 
 #ifdef TIOCGETP
 /*
@@ -1110,7 +1079,7 @@ int tty_perform_flush(struct tty_struct *tty, unsigned long arg)
 }
 EXPORT_SYMBOL_GPL(tty_perform_flush);
 
-int n_tty_ioctl(struct tty_struct *tty, struct file *file,
+int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
                       unsigned int cmd, unsigned long arg)
 {
        unsigned long flags;
@@ -1148,13 +1117,6 @@ int n_tty_ioctl(struct tty_struct *tty, struct file *file,
                return 0;
        case TCFLSH:
                return tty_perform_flush(tty, arg);
-       case TIOCOUTQ:
-               return put_user(tty_chars_in_buffer(tty), (int __user *) arg);
-       case TIOCINQ:
-               retval = tty->read_cnt;
-               if (L_ICANON(tty))
-                       retval = inq_canon(tty);
-               return put_user(retval, (unsigned int __user *) arg);
        case TIOCPKT:
        {
                int pktmode;
@@ -1180,4 +1142,4 @@ int n_tty_ioctl(struct tty_struct *tty, struct file *file,
                return tty_mode_ioctl(tty, file, cmd, arg);
        }
 }
-EXPORT_SYMBOL(n_tty_ioctl);
+EXPORT_SYMBOL(n_tty_ioctl_helper);
index 3c7c757..3b8121d 100644 (file)
@@ -466,7 +466,7 @@ static inline void tty_audit_push_task(struct task_struct *tsk,
 #endif
 
 /* tty_ioctl.c */
-extern int n_tty_ioctl(struct tty_struct *tty, struct file *file,
+extern int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file,
                       unsigned int cmd, unsigned long arg);
 
 /* serial.c */