ECHOCTL | ECHOKE | IEXTEN,
.c_cc = INIT_C_CC,
.c_ispeed = 38400,
- .c_ospeed = 38400
+ .c_ospeed = 38400,
+ /* .c_line = N_TTY, */
};
EXPORT_SYMBOL(tty_std_termios);
* Locking: none. Must be called after tty is definitely unused
*/
-void free_tty_struct(struct tty_struct *tty)
+static void free_tty_struct(struct tty_struct *tty)
{
- if (!tty)
- return;
+ tty_ldisc_deinit(tty);
put_device(tty->dev);
kfree(tty->write_buf);
tty->magic = 0xDEADDEAD;
while (refs--)
tty_kref_put(tty);
- tty_ldisc_hangup(tty);
+ tty_ldisc_hangup(tty, cons_filp != NULL);
spin_lock_irq(&tty->ctrl_lock);
clear_bit(TTY_THROTTLED, &tty->flags);
} else if (tty->ops->hangup)
tty->ops->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, which is now guaranteed.
*/
set_bit(TTY_HUPPED, &tty->flags);
tty_unlock(tty);
/* We want to wait for the line discipline to sort out in this
situation */
ld = tty_ldisc_ref_wait(tty);
+ if (!ld)
+ return hung_up_tty_read(file, buf, count, ppos);
if (ld->ops->read)
i = ld->ops->read(tty, file, buf, count);
else
if (tty->ops->write_room == NULL)
tty_err(tty, "missing write_room method\n");
ld = tty_ldisc_ref_wait(tty);
+ if (!ld)
+ return hung_up_tty_write(file, buf, count, ppos);
if (!ld->ops->write)
ret = -EIO;
else
* the tty_mutex currently so we can be relaxed about ordering.
*/
-int tty_init_termios(struct tty_struct *tty)
+void tty_init_termios(struct tty_struct *tty)
{
struct ktermios *tp;
int idx = tty->index;
else {
/* Check for lazy saved data */
tp = tty->driver->termios[idx];
- if (tp != NULL)
+ if (tp != NULL) {
tty->termios = *tp;
- else
+ tty->termios.c_line = tty->driver->init_termios.c_line;
+ } else
tty->termios = tty->driver->init_termios;
}
/* Compatibility until drivers always set this */
tty->termios.c_ispeed = tty_termios_input_baud_rate(&tty->termios);
tty->termios.c_ospeed = tty_termios_baud_rate(&tty->termios);
- return 0;
}
EXPORT_SYMBOL_GPL(tty_init_termios);
int tty_standard_install(struct tty_driver *driver, struct tty_struct *tty)
{
- int ret = tty_init_termios(tty);
- if (ret)
- return ret;
-
+ tty_init_termios(tty);
tty_driver_kref_get(driver);
tty->count++;
driver->ttys[tty->index] = tty;
*
* Locking: tty_mutex for now
*/
-void tty_driver_remove_tty(struct tty_driver *driver, struct tty_struct *tty)
+static void tty_driver_remove_tty(struct tty_driver *driver, struct tty_struct *tty)
{
if (driver->ops->remove)
driver->ops->remove(driver, tty);
{
struct tty_driver *driver = tty->driver;
- if (!tty->count)
- return -EIO;
-
if (driver->type == TTY_DRIVER_TYPE_PTY &&
driver->subtype == PTY_TYPE_MASTER)
return -EIO;
+ if (!tty->count)
+ return -EAGAIN;
+
if (test_bit(TTY_EXCLUSIVE, &tty->flags) && !capable(CAP_SYS_ADMIN))
return -EBUSY;
tty->count++;
- WARN_ON(!tty->ldisc);
+ if (!tty->ldisc)
+ return tty_ldisc_reinit(tty, tty->termios.c_line);
return 0;
}
tty_lock(tty);
retval = tty_driver_install_tty(driver, tty);
if (retval < 0)
- goto err_deinit_tty;
+ goto err_free_tty;
if (!tty->port)
tty->port = driver->ports[idx];
/* Return the tty locked so that it cannot vanish under the caller */
return tty;
-err_deinit_tty:
+err_free_tty:
tty_unlock(tty);
- deinitialize_tty_struct(tty);
free_tty_struct(tty);
err_module_put:
module_put(driver->owner);
return ERR_PTR(retval);
}
-void tty_free_termios(struct tty_struct *tty)
+static void tty_free_termios(struct tty_struct *tty)
{
struct ktermios *tp;
int idx = tty->index;
}
*tp = tty->termios;
}
-EXPORT_SYMBOL(tty_free_termios);
/**
* tty_flush_works - flush all works of a tty/pty pair
* Locking: tty_mutex protects get_tty_driver
*/
static struct tty_driver *tty_lookup_driver(dev_t device, struct file *filp,
- int *noctty, int *index)
+ int *index)
{
struct tty_driver *driver;
extern struct tty_driver *console_driver;
driver = tty_driver_kref_get(console_driver);
*index = fg_console;
- *noctty = 1;
break;
}
#endif
if (driver) {
/* Don't let /dev/console block */
filp->f_flags |= O_NONBLOCK;
- *noctty = 1;
break;
}
}
return driver;
}
+/**
+ * tty_open_by_driver - open a tty device
+ * @device: dev_t of device to open
+ * @inode: inode of device file
+ * @filp: file pointer to tty
+ *
+ * Performs the driver lookup, checks for a reopen, or otherwise
+ * performs the first-time tty initialization.
+ *
+ * Returns the locked initialized or re-opened &tty_struct
+ *
+ * Claims the global tty_mutex to serialize:
+ * - concurrent first-time tty initialization
+ * - concurrent tty driver removal w/ lookup
+ * - concurrent tty removal from driver table
+ */
+static struct tty_struct *tty_open_by_driver(dev_t device, struct inode *inode,
+ struct file *filp)
+{
+ struct tty_struct *tty;
+ struct tty_driver *driver = NULL;
+ int index = -1;
+ int retval;
+
+ mutex_lock(&tty_mutex);
+ driver = tty_lookup_driver(device, filp, &index);
+ if (IS_ERR(driver)) {
+ mutex_unlock(&tty_mutex);
+ return ERR_CAST(driver);
+ }
+
+ /* check whether we're reopening an existing tty */
+ tty = tty_driver_lookup_tty(driver, inode, index);
+ if (IS_ERR(tty)) {
+ mutex_unlock(&tty_mutex);
+ goto out;
+ }
+
+ if (tty) {
+ mutex_unlock(&tty_mutex);
+ retval = tty_lock_interruptible(tty);
+ if (retval) {
+ if (retval == -EINTR)
+ retval = -ERESTARTSYS;
+ tty = ERR_PTR(retval);
+ goto out;
+ }
+ /* safe to drop the kref from tty_driver_lookup_tty() */
+ tty_kref_put(tty);
+ retval = tty_reopen(tty);
+ if (retval < 0) {
+ tty_unlock(tty);
+ tty = ERR_PTR(retval);
+ }
+ } else { /* Returns with the tty_lock held for now */
+ tty = tty_init_dev(driver, index);
+ mutex_unlock(&tty_mutex);
+ }
+out:
+ tty_driver_kref_put(driver);
+ return tty;
+}
+
/**
* tty_open - open a tty device
* @inode: inode of device file
{
struct tty_struct *tty;
int noctty, retval;
- struct tty_driver *driver = NULL;
- int index;
dev_t device = inode->i_rdev;
unsigned saved_flags = filp->f_flags;
if (retval)
return -ENOMEM;
- noctty = filp->f_flags & O_NOCTTY;
- index = -1;
- retval = 0;
-
tty = tty_open_current_tty(device, filp);
- if (!tty) {
- mutex_lock(&tty_mutex);
- driver = tty_lookup_driver(device, filp, &noctty, &index);
- if (IS_ERR(driver)) {
- retval = PTR_ERR(driver);
- goto err_unlock;
- }
-
- /* check whether we're reopening an existing tty */
- tty = tty_driver_lookup_tty(driver, inode, index);
- if (IS_ERR(tty)) {
- retval = PTR_ERR(tty);
- goto err_unlock;
- }
-
- if (tty) {
- mutex_unlock(&tty_mutex);
- tty_lock(tty);
- /* safe to drop the kref from tty_driver_lookup_tty() */
- tty_kref_put(tty);
- retval = tty_reopen(tty);
- if (retval < 0) {
- tty_unlock(tty);
- tty = ERR_PTR(retval);
- }
- } else { /* Returns with the tty_lock held for now */
- tty = tty_init_dev(driver, index);
- mutex_unlock(&tty_mutex);
- }
-
- tty_driver_kref_put(driver);
- }
+ if (!tty)
+ tty = tty_open_by_driver(device, inode, filp);
if (IS_ERR(tty)) {
+ tty_free_file(filp);
retval = PTR_ERR(tty);
- goto err_file;
+ if (retval != -EAGAIN || signal_pending(current))
+ return retval;
+ schedule();
+ goto retry_open;
}
tty_add_file(tty, filp);
check_tty_count(tty, __func__);
- if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
- tty->driver->subtype == PTY_TYPE_MASTER)
- noctty = 1;
-
tty_debug_hangup(tty, "opening (count=%d)\n", tty->count);
if (tty->ops->open)
read_lock(&tasklist_lock);
spin_lock_irq(¤t->sighand->siglock);
+ noctty = (filp->f_flags & O_NOCTTY) ||
+ device == MKDEV(TTY_MAJOR, 0) ||
+ device == MKDEV(TTYAUX_MAJOR, 1) ||
+ (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
+ tty->driver->subtype == PTY_TYPE_MASTER);
+
if (!noctty &&
current->signal->leader &&
!current->signal->tty &&
read_unlock(&tasklist_lock);
tty_unlock(tty);
return 0;
-err_unlock:
- mutex_unlock(&tty_mutex);
- /* after locks to avoid deadlock */
- if (!IS_ERR_OR_NULL(driver))
- tty_driver_kref_put(driver);
-err_file:
- tty_free_file(filp);
- return retval;
}
return 0;
ld = tty_ldisc_ref_wait(tty);
+ if (!ld)
+ return hung_up_tty_poll(filp, wait);
if (ld->ops->poll)
ret = ld->ops->poll(tty, filp, wait);
tty_ldisc_deref(ld);
return -EFAULT;
tty_audit_tiocsti(tty, ch);
ld = tty_ldisc_ref_wait(tty);
+ if (!ld)
+ return -EIO;
ld->ops->receive_buf(tty, &ch, &mbz, 1);
tty_ldisc_deref(ld);
return 0;
static int tiocsetd(struct tty_struct *tty, int __user *p)
{
- int ldisc;
+ int disc;
int ret;
- if (get_user(ldisc, p))
+ if (get_user(disc, p))
return -EFAULT;
- ret = tty_set_ldisc(tty, ldisc);
+ ret = tty_set_ldisc(tty, disc);
return ret;
}
+/**
+ * tiocgetd - get line discipline
+ * @tty: tty device
+ * @p: pointer to user data
+ *
+ * Retrieves the line discipline id directly from the ldisc.
+ *
+ * Locking: waits for ldisc reference (in case the line discipline
+ * is changing or the tty is being hungup)
+ */
+
+static int tiocgetd(struct tty_struct *tty, int __user *p)
+{
+ struct tty_ldisc *ld;
+ int ret;
+
+ ld = tty_ldisc_ref_wait(tty);
+ if (!ld)
+ return -EIO;
+ ret = put_user(ld->ops->num, p);
+ tty_ldisc_deref(ld);
+ return ret;
+}
+
/**
* send_break - performed time break
* @tty: device to break on
case TIOCGSID:
return tiocgsid(tty, real_tty, p);
case TIOCGETD:
- return put_user(tty->ldisc->ops->num, (int __user *)p);
+ return tiocgetd(tty, p);
case TIOCSETD:
return tiocsetd(tty, p);
case TIOCVHANGUP:
return retval;
}
ld = tty_ldisc_ref_wait(tty);
+ if (!ld)
+ return hung_up_tty_ioctl(file, cmd, arg);
retval = -EINVAL;
if (ld->ops->ioctl) {
retval = ld->ops->ioctl(tty, file, cmd, arg);
}
ld = tty_ldisc_ref_wait(tty);
+ if (!ld)
+ return hung_up_tty_compat_ioctl(file, cmd, arg);
if (ld->ops->compat_ioctl)
retval = ld->ops->compat_ioctl(tty, file, cmd, arg);
else
return tty;
}
-/**
- * deinitialize_tty_struct
- * @tty: tty to deinitialize
- *
- * This subroutine deinitializes a tty structure that has been newly
- * allocated but tty_release cannot be called on that yet.
- *
- * Locking: none - tty in question must not be exposed at this point
- */
-void deinitialize_tty_struct(struct tty_struct *tty)
-{
- tty_ldisc_deinit(tty);
-}
-
/**
* tty_put_char - write one character to a tty
* @tty: tty
projects / karo-tx-linux.git / blobdiff