#include <linux/selection.h>
#include <linux/kmod.h>
+#include <linux/nsproxy.h>
#undef TTY_DEBUG_HANGUP
extern struct tty_driver *ptm_driver; /* Unix98 pty masters; for /dev/ptmx */
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
}
/**
- * tty_buffer_flush - flush full tty buffers
+ * __tty_buffer_flush - flush full tty buffers
* @tty: tty to flush
*
- * flush all the buffers containing receive data
+ * 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: none
+ * Locking: Caller must hold tty->buf.lock
*/
-static void tty_buffer_flush(struct tty_struct *tty)
+static void __tty_buffer_flush(struct tty_struct *tty)
{
struct tty_buffer *thead;
- unsigned long flags;
- spin_lock_irqsave(&tty->buf.lock, flags);
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: 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.
*
* 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)
* @tty: tty to start
*
* Start a tty that has been stopped if at all possible. Perform
- * any neccessary wakeups and propagate 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.
*
}
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 (!*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;
#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
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);
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
* @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 ??
*/
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);
}
/**
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;
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);
}
/**
/* 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
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;
}
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;
}
return;
spin_lock_irqsave(&tty->buf.lock, flags);
+ set_bit(TTY_FLUSHING, &tty->flags); /* So we know a flush is running */
head = tty->buf.head;
if (head != NULL) {
tty->buf.head = NULL;
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;
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);
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);
}
}
-#ifdef CONFIG_VT
-extern int vty_init(void);
-#endif
-
static int __init tty_class_init(void)
{
tty_class = class_create(THIS_MODULE, "tty");