* at hangup) or when the N_TTY line discipline internally has to
* clean the pending queue (for example some signals).
*
- * FIXME: tty->ctrl_status is not spinlocked and relies on
- * lock_kernel() still.
+ * Locking: ctrl_lock
*/
static void n_tty_flush_buffer(struct tty_struct *tty)
{
+ unsigned long flags;
/* clear everything and unthrottle the driver */
reset_buffer_flags(tty);
if (!tty->link)
return;
+ spin_lock_irqsave(&tty->ctrl_lock, flags);
if (tty->link->packet) {
tty->ctrl_status |= TIOCPKT_FLUSHREAD;
wake_up_interruptible(&tty->link->read_wait);
}
+ spin_unlock_irqrestore(&tty->ctrl_lock, flags);
}
/**
* relevant in the world today. If you ever need them, add them here.
*
* Called from both the receive and transmit sides and can be called
- * re-entrantly. Relies on lock_kernel() still.
+ * re-entrantly. Relies on lock_kernel() for tty->column state.
*/
static int opost(unsigned char c, struct tty_struct *tty)
if (!space)
return -1;
+ lock_kernel();
if (O_OPOST(tty)) {
switch (c) {
case '\n':
}
}
tty->driver->put_char(tty, c);
+ unlock_kernel();
return 0;
}
* the simple cases normally found and helps to generate blocks of
* symbols for the console driver and thus improve performance.
*
- * Called from write_chan under the tty layer write lock.
+ * Called from write_chan under the tty layer write lock. Relies
+ * on lock_kernel for the tty->column state.
*/
static ssize_t opost_block(struct tty_struct *tty,
if (nr > space)
nr = space;
+ lock_kernel();
for (i = 0, cp = buf; i < nr; i++, cp++) {
switch (*cp) {
case '\n':
if (tty->driver->flush_chars)
tty->driver->flush_chars(tty);
i = tty->driver->write(tty, buf, i);
+ unlock_kernel();
return i;
}
if (tty->stopped && !tty->flow_stopped && I_IXON(tty) &&
((I_IXANY(tty) && c != START_CHAR(tty) && c != STOP_CHAR(tty)) ||
- c == INTR_CHAR(tty) || c == QUIT_CHAR(tty)))
+ c == INTR_CHAR(tty) || c == QUIT_CHAR(tty) || c == SUSP_CHAR(tty)))
start_tty(tty);
if (tty->closing) {
return;
}
- if (c == '\r') {
- if (I_IGNCR(tty))
- return;
- if (I_ICRNL(tty))
- c = '\n';
- } else if (c == '\n' && I_INLCR(tty))
- c = '\r';
if (I_IXON(tty)) {
if (c == START_CHAR(tty)) {
start_tty(tty);
return;
}
}
+
if (L_ISIG(tty)) {
int signal;
signal = SIGINT;
return;
}
}
+
+ if (c == '\r') {
+ if (I_IGNCR(tty))
+ return;
+ if (I_ICRNL(tty))
+ c = '\n';
+ } else if (c == '\n' && I_INLCR(tty))
+ c = '\r';
+
if (tty->icanon) {
if (c == ERASE_CHAR(tty) || c == KILL_CHAR(tty) ||
(c == WERASE_CHAR(tty) && L_IEXTEN(tty))) {
* Perform job control management checks on this file/tty descriptor
* and if appropriate send any needed signals and return a negative
* error code if action should be taken.
+ *
+ * FIXME:
+ * Locking: None - redirected write test is safe, testing
+ * current->signal should possibly lock current->sighand
+ * pgrp locking ?
*/
static int job_control(struct tty_struct *tty, struct file *file)
ssize_t size;
long timeout;
unsigned long flags;
+ int packet;
do_it_again:
if (mutex_lock_interruptible(&tty->atomic_read_lock))
return -ERESTARTSYS;
}
+ packet = tty->packet;
add_wait_queue(&tty->read_wait, &wait);
while (nr) {
/* First test for status change. */
- if (tty->packet && tty->link->ctrl_status) {
+ if (packet && tty->link->ctrl_status) {
unsigned char cs;
if (b != buf)
break;
+ spin_lock_irqsave(&tty->link->ctrl_lock, flags);
cs = tty->link->ctrl_status;
tty->link->ctrl_status = 0;
+ spin_unlock_irqrestore(&tty->link->ctrl_lock, flags);
if (tty_put_user(tty, cs, b++)) {
retval = -EFAULT;
b--;
retval = -ERESTARTSYS;
break;
}
+ /* FIXME: does n_tty_set_room need locking ? */
n_tty_set_room(tty);
timeout = schedule_timeout(timeout);
continue;
__set_current_state(TASK_RUNNING);
/* Deal with packet mode. */
- if (tty->packet && b == buf) {
+ if (packet && b == buf) {
if (tty_put_user(tty, TIOCPKT_DATA, b++)) {
retval = -EFAULT;
b--;
break;
} else {
int uncopied;
+ /* The copy function takes the read lock and handles
+ locking internally for this case */
uncopied = copy_from_read_buf(tty, &b, &nr);
uncopied += copy_from_read_buf(tty, &b, &nr);
if (uncopied) {
goto do_it_again;
n_tty_set_room(tty);
-
return retval;
}