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path: root/drivers/tty/pty.c
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Diffstat (limited to 'drivers/tty/pty.c')
-rw-r--r--drivers/tty/pty.c234
1 files changed, 122 insertions, 112 deletions
diff --git a/drivers/tty/pty.c b/drivers/tty/pty.c
index 5505ffc91da4..a82b39939a9c 100644
--- a/drivers/tty/pty.c
+++ b/drivers/tty/pty.c
@@ -47,6 +47,7 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
wake_up_interruptible(&tty->read_wait);
wake_up_interruptible(&tty->write_wait);
tty->packet = 0;
+ /* Review - krefs on tty_link ?? */
if (!tty->link)
return;
tty->link->packet = 0;
@@ -62,9 +63,9 @@ static void pty_close(struct tty_struct *tty, struct file *filp)
mutex_unlock(&devpts_mutex);
}
#endif
- tty_unlock();
+ tty_unlock(tty);
tty_vhangup(tty->link);
- tty_lock();
+ tty_lock(tty);
}
}
@@ -231,8 +232,8 @@ out:
static void pty_set_termios(struct tty_struct *tty,
struct ktermios *old_termios)
{
- tty->termios->c_cflag &= ~(CSIZE | PARENB);
- tty->termios->c_cflag |= (CS8 | CREAD);
+ tty->termios.c_cflag &= ~(CSIZE | PARENB);
+ tty->termios.c_cflag |= (CS8 | CREAD);
}
/**
@@ -282,60 +283,110 @@ done:
return 0;
}
-/* Traditional BSD devices */
-#ifdef CONFIG_LEGACY_PTYS
-
-static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
+/**
+ * pty_common_install - set up the pty pair
+ * @driver: the pty driver
+ * @tty: the tty being instantiated
+ * @bool: legacy, true if this is BSD style
+ *
+ * Perform the initial set up for the tty/pty pair. Called from the
+ * tty layer when the port is first opened.
+ *
+ * Locking: the caller must hold the tty_mutex
+ */
+static int pty_common_install(struct tty_driver *driver, struct tty_struct *tty,
+ bool legacy)
{
struct tty_struct *o_tty;
+ struct tty_port *ports[2];
int idx = tty->index;
- int retval;
+ int retval = -ENOMEM;
o_tty = alloc_tty_struct();
if (!o_tty)
- return -ENOMEM;
+ goto err;
+ ports[0] = kmalloc(sizeof **ports, GFP_KERNEL);
+ ports[1] = kmalloc(sizeof **ports, GFP_KERNEL);
+ if (!ports[0] || !ports[1])
+ goto err_free_tty;
if (!try_module_get(driver->other->owner)) {
/* This cannot in fact currently happen */
- retval = -ENOMEM;
goto err_free_tty;
}
initialize_tty_struct(o_tty, driver->other, idx);
- /* We always use new tty termios data so we can do this
- the easy way .. */
- retval = tty_init_termios(tty);
- if (retval)
- goto err_deinit_tty;
-
- retval = tty_init_termios(o_tty);
- if (retval)
- goto err_free_termios;
+ if (legacy) {
+ /* We always use new tty termios data so we can do this
+ the easy way .. */
+ retval = tty_init_termios(tty);
+ if (retval)
+ goto err_deinit_tty;
+
+ retval = tty_init_termios(o_tty);
+ if (retval)
+ goto err_free_termios;
+
+ driver->other->ttys[idx] = o_tty;
+ driver->ttys[idx] = tty;
+ } else {
+ memset(&tty->termios_locked, 0, sizeof(tty->termios_locked));
+ tty->termios = driver->init_termios;
+ memset(&o_tty->termios_locked, 0, sizeof(tty->termios_locked));
+ o_tty->termios = driver->other->init_termios;
+ }
/*
* Everything allocated ... set up the o_tty structure.
*/
- driver->other->ttys[idx] = o_tty;
tty_driver_kref_get(driver->other);
if (driver->subtype == PTY_TYPE_MASTER)
o_tty->count++;
/* Establish the links in both directions */
tty->link = o_tty;
o_tty->link = tty;
+ tty_port_init(ports[0]);
+ tty_port_init(ports[1]);
+ o_tty->port = ports[0];
+ tty->port = ports[1];
tty_driver_kref_get(driver);
tty->count++;
- driver->ttys[idx] = tty;
return 0;
err_free_termios:
- tty_free_termios(tty);
+ if (legacy)
+ tty_free_termios(tty);
err_deinit_tty:
deinitialize_tty_struct(o_tty);
module_put(o_tty->driver->owner);
err_free_tty:
+ kfree(ports[0]);
+ kfree(ports[1]);
free_tty_struct(o_tty);
+err:
return retval;
}
+static void pty_cleanup(struct tty_struct *tty)
+{
+ kfree(tty->port);
+}
+
+/* Traditional BSD devices */
+#ifdef CONFIG_LEGACY_PTYS
+
+static int pty_install(struct tty_driver *driver, struct tty_struct *tty)
+{
+ return pty_common_install(driver, tty, true);
+}
+
+static void pty_remove(struct tty_driver *driver, struct tty_struct *tty)
+{
+ struct tty_struct *pair = tty->link;
+ driver->ttys[tty->index] = NULL;
+ if (pair)
+ pair->driver->ttys[pair->index] = NULL;
+}
+
static int pty_bsd_ioctl(struct tty_struct *tty,
unsigned int cmd, unsigned long arg)
{
@@ -366,7 +417,9 @@ static const struct tty_operations master_pty_ops_bsd = {
.unthrottle = pty_unthrottle,
.set_termios = pty_set_termios,
.ioctl = pty_bsd_ioctl,
- .resize = pty_resize
+ .cleanup = pty_cleanup,
+ .resize = pty_resize,
+ .remove = pty_remove
};
static const struct tty_operations slave_pty_ops_bsd = {
@@ -379,7 +432,9 @@ static const struct tty_operations slave_pty_ops_bsd = {
.chars_in_buffer = pty_chars_in_buffer,
.unthrottle = pty_unthrottle,
.set_termios = pty_set_termios,
- .resize = pty_resize
+ .cleanup = pty_cleanup,
+ .resize = pty_resize,
+ .remove = pty_remove
};
static void __init legacy_pty_init(void)
@@ -389,12 +444,18 @@ static void __init legacy_pty_init(void)
if (legacy_count <= 0)
return;
- pty_driver = alloc_tty_driver(legacy_count);
- if (!pty_driver)
+ pty_driver = tty_alloc_driver(legacy_count,
+ TTY_DRIVER_RESET_TERMIOS |
+ TTY_DRIVER_REAL_RAW |
+ TTY_DRIVER_DYNAMIC_ALLOC);
+ if (IS_ERR(pty_driver))
panic("Couldn't allocate pty driver");
- pty_slave_driver = alloc_tty_driver(legacy_count);
- if (!pty_slave_driver)
+ pty_slave_driver = tty_alloc_driver(legacy_count,
+ TTY_DRIVER_RESET_TERMIOS |
+ TTY_DRIVER_REAL_RAW |
+ TTY_DRIVER_DYNAMIC_ALLOC);
+ if (IS_ERR(pty_slave_driver))
panic("Couldn't allocate pty slave driver");
pty_driver->driver_name = "pty_master";
@@ -410,7 +471,6 @@ static void __init legacy_pty_init(void)
pty_driver->init_termios.c_lflag = 0;
pty_driver->init_termios.c_ispeed = 38400;
pty_driver->init_termios.c_ospeed = 38400;
- pty_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW;
pty_driver->other = pty_slave_driver;
tty_set_operations(pty_driver, &master_pty_ops_bsd);
@@ -424,8 +484,6 @@ static void __init legacy_pty_init(void)
pty_slave_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
pty_slave_driver->init_termios.c_ispeed = 38400;
pty_slave_driver->init_termios.c_ospeed = 38400;
- pty_slave_driver->flags = TTY_DRIVER_RESET_TERMIOS |
- TTY_DRIVER_REAL_RAW;
pty_slave_driver->other = pty_driver;
tty_set_operations(pty_slave_driver, &slave_pty_ops_bsd);
@@ -497,78 +555,22 @@ static struct tty_struct *pts_unix98_lookup(struct tty_driver *driver,
return tty;
}
-static void pty_unix98_shutdown(struct tty_struct *tty)
-{
- tty_driver_remove_tty(tty->driver, tty);
- /* We have our own method as we don't use the tty index */
- kfree(tty->termios);
-}
-
/* We have no need to install and remove our tty objects as devpts does all
the work for us */
static int pty_unix98_install(struct tty_driver *driver, struct tty_struct *tty)
{
- struct tty_struct *o_tty;
- int idx = tty->index;
-
- o_tty = alloc_tty_struct();
- if (!o_tty)
- return -ENOMEM;
- if (!try_module_get(driver->other->owner)) {
- /* This cannot in fact currently happen */
- goto err_free_tty;
- }
- initialize_tty_struct(o_tty, driver->other, idx);
-
- tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
- if (tty->termios == NULL)
- goto err_free_mem;
- *tty->termios = driver->init_termios;
- tty->termios_locked = tty->termios + 1;
-
- o_tty->termios = kzalloc(sizeof(struct ktermios[2]), GFP_KERNEL);
- if (o_tty->termios == NULL)
- goto err_free_mem;
- *o_tty->termios = driver->other->init_termios;
- o_tty->termios_locked = o_tty->termios + 1;
-
- tty_driver_kref_get(driver->other);
- if (driver->subtype == PTY_TYPE_MASTER)
- o_tty->count++;
- /* Establish the links in both directions */
- tty->link = o_tty;
- o_tty->link = tty;
- /*
- * All structures have been allocated, so now we install them.
- * Failures after this point use release_tty to clean up, so
- * there's no need to null out the local pointers.
- */
- tty_driver_kref_get(driver);
- tty->count++;
- return 0;
-err_free_mem:
- deinitialize_tty_struct(o_tty);
- kfree(o_tty->termios);
- kfree(tty->termios);
- module_put(o_tty->driver->owner);
-err_free_tty:
- free_tty_struct(o_tty);
- return -ENOMEM;
-}
-
-static void ptm_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
-{
+ return pty_common_install(driver, tty, false);
}
-static void pts_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
+static void pty_unix98_remove(struct tty_driver *driver, struct tty_struct *tty)
{
}
static const struct tty_operations ptm_unix98_ops = {
.lookup = ptm_unix98_lookup,
.install = pty_unix98_install,
- .remove = ptm_unix98_remove,
+ .remove = pty_unix98_remove,
.open = pty_open,
.close = pty_close,
.write = pty_write,
@@ -578,14 +580,14 @@ static const struct tty_operations ptm_unix98_ops = {
.unthrottle = pty_unthrottle,
.set_termios = pty_set_termios,
.ioctl = pty_unix98_ioctl,
- .shutdown = pty_unix98_shutdown,
- .resize = pty_resize
+ .resize = pty_resize,
+ .cleanup = pty_cleanup
};
static const struct tty_operations pty_unix98_ops = {
.lookup = pts_unix98_lookup,
.install = pty_unix98_install,
- .remove = pts_unix98_remove,
+ .remove = pty_unix98_remove,
.open = pty_open,
.close = pty_close,
.write = pty_write,
@@ -594,7 +596,7 @@ static const struct tty_operations pty_unix98_ops = {
.chars_in_buffer = pty_chars_in_buffer,
.unthrottle = pty_unthrottle,
.set_termios = pty_set_termios,
- .shutdown = pty_unix98_shutdown
+ .cleanup = pty_cleanup,
};
/**
@@ -622,26 +624,28 @@ static int ptmx_open(struct inode *inode, struct file *filp)
return retval;
/* find a device that is not in use. */
- tty_lock();
+ mutex_lock(&devpts_mutex);
index = devpts_new_index(inode);
- tty_unlock();
if (index < 0) {
retval = index;
+ mutex_unlock(&devpts_mutex);
goto err_file;
}
+ mutex_unlock(&devpts_mutex);
+
mutex_lock(&tty_mutex);
- mutex_lock(&devpts_mutex);
tty = tty_init_dev(ptm_driver, index);
- mutex_unlock(&devpts_mutex);
- tty_lock();
- mutex_unlock(&tty_mutex);
if (IS_ERR(tty)) {
retval = PTR_ERR(tty);
goto out;
}
+ /* The tty returned here is locked so we can safely
+ drop the mutex */
+ mutex_unlock(&tty_mutex);
+
set_bit(TTY_PTY_LOCK, &tty->flags); /* LOCK THE SLAVE */
tty_add_file(tty, filp);
@@ -654,15 +658,15 @@ static int ptmx_open(struct inode *inode, struct file *filp)
if (retval)
goto err_release;
- tty_unlock();
+ tty_unlock(tty);
return 0;
err_release:
- tty_unlock();
+ tty_unlock(tty);
tty_release(inode, filp);
return retval;
out:
+ mutex_unlock(&tty_mutex);
devpts_kill_index(inode, index);
- tty_unlock();
err_file:
tty_free_file(filp);
return retval;
@@ -672,11 +676,21 @@ static struct file_operations ptmx_fops;
static void __init unix98_pty_init(void)
{
- ptm_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
- if (!ptm_driver)
+ ptm_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
+ TTY_DRIVER_RESET_TERMIOS |
+ TTY_DRIVER_REAL_RAW |
+ TTY_DRIVER_DYNAMIC_DEV |
+ TTY_DRIVER_DEVPTS_MEM |
+ TTY_DRIVER_DYNAMIC_ALLOC);
+ if (IS_ERR(ptm_driver))
panic("Couldn't allocate Unix98 ptm driver");
- pts_driver = alloc_tty_driver(NR_UNIX98_PTY_MAX);
- if (!pts_driver)
+ pts_driver = tty_alloc_driver(NR_UNIX98_PTY_MAX,
+ TTY_DRIVER_RESET_TERMIOS |
+ TTY_DRIVER_REAL_RAW |
+ TTY_DRIVER_DYNAMIC_DEV |
+ TTY_DRIVER_DEVPTS_MEM |
+ TTY_DRIVER_DYNAMIC_ALLOC);
+ if (IS_ERR(pts_driver))
panic("Couldn't allocate Unix98 pts driver");
ptm_driver->driver_name = "pty_master";
@@ -692,8 +706,6 @@ static void __init unix98_pty_init(void)
ptm_driver->init_termios.c_lflag = 0;
ptm_driver->init_termios.c_ispeed = 38400;
ptm_driver->init_termios.c_ospeed = 38400;
- ptm_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
- TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
ptm_driver->other = pts_driver;
tty_set_operations(ptm_driver, &ptm_unix98_ops);
@@ -707,8 +719,6 @@ static void __init unix98_pty_init(void)
pts_driver->init_termios.c_cflag = B38400 | CS8 | CREAD;
pts_driver->init_termios.c_ispeed = 38400;
pts_driver->init_termios.c_ospeed = 38400;
- pts_driver->flags = TTY_DRIVER_RESET_TERMIOS | TTY_DRIVER_REAL_RAW |
- TTY_DRIVER_DYNAMIC_DEV | TTY_DRIVER_DEVPTS_MEM;
pts_driver->other = ptm_driver;
tty_set_operations(pts_driver, &pty_unix98_ops);