void free_tty_struct(struct tty_struct *tty)
{
+ if (!tty)
+ return;
if (tty->dev)
put_device(tty->dev);
kfree(tty->write_buf);
*/
static void tty_line_name(struct tty_driver *driver, int index, char *p)
{
- sprintf(p, "%s%d", driver->name, index + driver->name_base);
+ if (driver->flags & TTY_DRIVER_UNNUMBERED_NODE)
+ strcpy(p, driver->name);
+ else
+ sprintf(p, "%s%d", driver->name, index + driver->name_base);
}
/**
struct ktermios *tp;
int idx = tty->index;
- tp = tty->driver->termios[idx];
- if (tp == NULL) {
- tp = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
- if (tp == NULL)
- return -ENOMEM;
- memcpy(tp, &tty->driver->init_termios,
- sizeof(struct ktermios));
- tty->driver->termios[idx] = tp;
+ if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS)
+ tty->termios = tty->driver->init_termios;
+ else {
+ /* Check for lazy saved data */
+ tp = tty->driver->termios[idx];
+ if (tp != NULL)
+ tty->termios = *tp;
+ else
+ tty->termios = tty->driver->init_termios;
}
- tty->termios = tp;
- tty->termios_locked = tp + 1;
-
/* 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);
+ 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);
{
struct ktermios *tp;
int idx = tty->index;
- /* Kill this flag and push into drivers for locking etc */
- if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS) {
- /* FIXME: Locking on ->termios array */
- tp = tty->termios;
- tty->driver->termios[idx] = NULL;
- kfree(tp);
+
+ /* If the port is going to reset then it has no termios to save */
+ if (tty->driver->flags & TTY_DRIVER_RESET_TERMIOS)
+ return;
+
+ /* Stash the termios data */
+ tp = tty->driver->termios[idx];
+ if (tp == NULL) {
+ tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
+ if (tp == NULL) {
+ pr_warn("tty: no memory to save termios state.\n");
+ return;
+ }
+ tty->driver->termios[idx] = tp;
}
+ *tp = tty->termios;
}
EXPORT_SYMBOL(tty_free_termios);
-void tty_shutdown(struct tty_struct *tty)
-{
- tty_driver_remove_tty(tty->driver, tty);
- tty_free_termios(tty);
-}
-EXPORT_SYMBOL(tty_shutdown);
/**
* release_one_tty - release tty structure memory
* in use. It also gets called when setup of a device fails.
*
* Locking:
- * tty_mutex - sometimes only
* takes the file list lock internally when working on the list
* of ttys that the driver keeps.
*
{
struct tty_struct *tty = container_of(kref, struct tty_struct, kref);
- if (tty->ops->shutdown)
- tty->ops->shutdown(tty);
- else
- tty_shutdown(tty);
-
/* The hangup queue is now free so we can reuse it rather than
waste a chunk of memory for each port */
INIT_WORK(&tty->hangup_work, release_one_tty);
* and decrement the refcount of the backing module.
*
* Locking:
- * tty_mutex - sometimes only
+ * tty_mutex
* takes the file list lock internally when working on the list
* of ttys that the driver keeps.
- * FIXME: should we require tty_mutex is held here ??
*
*/
static void release_tty(struct tty_struct *tty, int idx)
{
/* This should always be true but check for the moment */
WARN_ON(tty->index != idx);
+ WARN_ON(!mutex_is_locked(&tty_mutex));
+ if (tty->ops->shutdown)
+ tty->ops->shutdown(tty);
+ tty_free_termios(tty);
+ tty_driver_remove_tty(tty->driver, tty);
if (tty->link)
tty_kref_put(tty->link);
__func__, idx, tty->name);
return -1;
}
- if (tty->termios != tty->driver->termios[idx]) {
- printk(KERN_DEBUG "%s: driver.termios[%d] not termios for (%s)\n",
- __func__, idx, tty->name);
- return -1;
- }
if (tty->driver->other) {
if (o_tty != tty->driver->other->ttys[idx]) {
printk(KERN_DEBUG "%s: other->table[%d] not o_tty for (%s)\n",
__func__, idx, tty->name);
return -1;
}
- if (o_tty->termios != tty->driver->other->termios[idx]) {
- printk(KERN_DEBUG "%s: other->termios[%d] not o_termios for (%s)\n",
- __func__, idx, tty->name);
- return -1;
- }
if (o_tty->link != tty) {
printk(KERN_DEBUG "%s: bad pty pointers\n", __func__);
return -1;
* The closing flags are now consistent with the open counts on
* both sides, and we've completed the last operation that could
* block, so it's safe to proceed with closing.
+ *
+ * We must *not* drop the tty_mutex until we ensure that a further
+ * entry into tty_open can not pick up this tty.
*/
if (pty_master) {
if (--o_tty->count < 0) {
}
mutex_unlock(&tty_mutex);
+ tty_unlock_pair(tty, o_tty);
+ /* At this point the TTY_CLOSING flag should ensure a dead tty
+ cannot be re-opened by a racing opener */
/* check whether both sides are closing ... */
- if (!tty_closing || (o_tty && !o_tty_closing)) {
- tty_unlock_pair(tty, o_tty);
+ if (!tty_closing || (o_tty && !o_tty_closing))
return 0;
- }
#ifdef TTY_DEBUG_HANGUP
printk(KERN_DEBUG "%s: freeing tty structure...\n", __func__);
* should be safe as we keep a kref while the tty is locked (so the
* unlock never unlocks a freed tty).
*/
+ mutex_lock(&tty_mutex);
release_tty(tty, idx);
- tty_unlock_pair(tty, o_tty);
+ mutex_unlock(&tty_mutex);
/* Make this pty number available for reallocation */
if (devpts)
}
EXPORT_SYMBOL(tty_unregister_device);
-struct tty_driver *__alloc_tty_driver(int lines, struct module *owner)
+/**
+ * __tty_alloc_driver -- allocate tty driver
+ * @lines: count of lines this driver can handle at most
+ * @owner: module which is repsonsible for this driver
+ * @flags: some of TTY_DRIVER_* flags, will be set in driver->flags
+ *
+ * This should not be called directly, some of the provided macros should be
+ * used instead. Use IS_ERR and friends on @retval.
+ */
+struct tty_driver *__tty_alloc_driver(unsigned int lines, struct module *owner,
+ unsigned long flags)
{
struct tty_driver *driver;
+ int err;
+
+ if (!lines || (flags & TTY_DRIVER_UNNUMBERED_NODE && lines > 1))
+ return ERR_PTR(-EINVAL);
driver = kzalloc(sizeof(struct tty_driver), GFP_KERNEL);
- if (driver) {
- kref_init(&driver->kref);
- driver->magic = TTY_DRIVER_MAGIC;
- driver->num = lines;
- driver->owner = owner;
- /* later we'll move allocation of tables here */
+ if (!driver)
+ return ERR_PTR(-ENOMEM);
+
+ kref_init(&driver->kref);
+ driver->magic = TTY_DRIVER_MAGIC;
+ driver->num = lines;
+ driver->owner = owner;
+ driver->flags = flags;
+
+ if (!(flags & TTY_DRIVER_DEVPTS_MEM)) {
+ driver->ttys = kcalloc(lines, sizeof(*driver->ttys),
+ GFP_KERNEL);
+ driver->termios = kcalloc(lines, sizeof(*driver->termios),
+ GFP_KERNEL);
+ if (!driver->ttys || !driver->termios) {
+ err = -ENOMEM;
+ goto err_free_all;
+ }
+ }
+
+ if (!(flags & TTY_DRIVER_DYNAMIC_ALLOC)) {
+ driver->ports = kcalloc(lines, sizeof(*driver->ports),
+ GFP_KERNEL);
+ if (!driver->ports) {
+ err = -ENOMEM;
+ goto err_free_all;
+ }
}
+
return driver;
+err_free_all:
+ kfree(driver->ports);
+ kfree(driver->ttys);
+ kfree(driver->termios);
+ kfree(driver);
+ return ERR_PTR(err);
}
-EXPORT_SYMBOL(__alloc_tty_driver);
+EXPORT_SYMBOL(__tty_alloc_driver);
static void destruct_tty_driver(struct kref *kref)
{
struct tty_driver *driver = container_of(kref, struct tty_driver, kref);
int i;
struct ktermios *tp;
- void *p;
if (driver->flags & TTY_DRIVER_INSTALLED) {
/*
if (!(driver->flags & TTY_DRIVER_DYNAMIC_DEV))
tty_unregister_device(driver, i);
}
- p = driver->ttys;
proc_tty_unregister_driver(driver);
- driver->ttys = NULL;
- driver->termios = NULL;
- kfree(p);
cdev_del(&driver->cdev);
}
kfree(driver->ports);
+ kfree(driver->termios);
+ kfree(driver->ttys);
kfree(driver);
}
int error;
int i;
dev_t dev;
- void **p = NULL;
struct device *d;
- if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM) && driver->num) {
- p = kzalloc(driver->num * 2 * sizeof(void *), GFP_KERNEL);
- if (!p)
- return -ENOMEM;
- }
- /*
- * There is too many lines in PTY and we won't need the array there
- * since it has an ->install hook where it assigns ports properly.
- */
- if (driver->type != TTY_DRIVER_TYPE_PTY) {
- driver->ports = kcalloc(driver->num, sizeof(struct tty_port *),
- GFP_KERNEL);
- if (!driver->ports) {
- error = -ENOMEM;
- goto err_free_p;
- }
- }
-
if (!driver->major) {
error = alloc_chrdev_region(&dev, driver->minor_start,
driver->num, driver->name);
error = register_chrdev_region(dev, driver->num, driver->name);
}
if (error < 0)
- goto err_free_p;
-
- if (p) {
- driver->ttys = (struct tty_struct **)p;
- driver->termios = (struct ktermios **)(p + driver->num);
- } else {
- driver->ttys = NULL;
- driver->termios = NULL;
- }
+ goto err;
cdev_init(&driver->cdev, &tty_fops);
driver->cdev.owner = driver->owner;
d = tty_register_device(driver, i, NULL);
if (IS_ERR(d)) {
error = PTR_ERR(d);
- goto err;
+ goto err_unreg_devs;
}
}
}
driver->flags |= TTY_DRIVER_INSTALLED;
return 0;
-err:
+err_unreg_devs:
for (i--; i >= 0; i--)
tty_unregister_device(driver, i);
err_unreg_char:
unregister_chrdev_region(dev, driver->num);
- driver->ttys = NULL;
- driver->termios = NULL;
-err_free_p: /* destruct_tty_driver will free driver->ports */
- kfree(p);
+err:
return error;
}
EXPORT_SYMBOL(tty_register_driver);
projects / linux-2.6-block.git / blobdiff