DEFINE_MUTEX(tty_mutex);
EXPORT_SYMBOL(tty_mutex);
-static void initialize_tty_struct(struct tty_struct *tty);
-
static ssize_t tty_read(struct file *, char __user *, size_t, loff_t *);
static ssize_t tty_write(struct file *, const char __user *, size_t, loff_t *);
ssize_t redirected_tty_write(struct file *, const char __user *,
* Locking: none
*/
-static struct tty_struct *alloc_tty_struct(void)
+struct tty_struct *alloc_tty_struct(void)
{
return kzalloc(sizeof(struct tty_struct), GFP_KERNEL);
}
* Locking: none. Must be called after tty is definitely unused
*/
-static inline void free_tty_struct(struct tty_struct *tty)
+void free_tty_struct(struct tty_struct *tty)
{
kfree(tty->write_buf);
tty_buffer_free_all(tty);
}
/**
- * pty_line_name - generate name for a tty
+ * tty_line_name - generate name for a tty
* @driver: the tty driver in use
* @index: the minor number
* @p: output buffer of at least 7 bytes
* be held until the 'fast-open' is also done. Will change once we
* have refcounting in the driver and per driver locking
*/
-struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver, int idx)
+struct tty_struct *tty_driver_lookup_tty(struct tty_driver *driver,
+ struct inode *inode, int idx)
{
struct tty_struct *tty;
if (driver->ops->lookup)
- return driver->ops->lookup(driver, idx);
+ return driver->ops->lookup(driver, inode, idx);
- tty = driver->ttys[idx];
+ tty = driver->ttys[idx];
return tty;
}
/**
- * tty_reopen() - fast re-open of an open tty
- * @tty - the tty to open
+ * tty_init_termios - helper for termios setup
+ * @tty: the tty to set up
+ *
+ * Initialise the termios structures for this tty. Thus runs under
+ * the tty_mutex currently so we can be relaxed about ordering.
+ */
+
+int tty_init_termios(struct tty_struct *tty)
+{
+ struct ktermios *tp, *ltp;
+ int idx = tty->index;
+
+ tp = tty->driver->termios[idx];
+ ltp = tty->driver->termios_locked[idx];
+ if (tp == NULL) {
+ WARN_ON(ltp != NULL);
+ tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
+ ltp = kzalloc(sizeof(struct ktermios), GFP_KERNEL);
+ if (tp == NULL || ltp == NULL) {
+ kfree(tp);
+ kfree(ltp);
+ return -ENOMEM;
+ }
+ memcpy(tp, &tty->driver->init_termios,
+ sizeof(struct ktermios));
+ tty->driver->termios[idx] = tp;
+ tty->driver->termios_locked[idx] = ltp;
+ }
+ tty->termios = tp;
+ tty->termios_locked = ltp;
+
+ /* 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;
+}
+
+/**
+ * tty_driver_install_tty() - install a tty entry in the driver
+ * @driver: the driver for the tty
+ * @tty: the tty
+ *
+ * Install a tty object into the driver tables. The tty->index field
+ * will be set by the time this is called. This method is responsible
+ * for ensuring any need additional structures are allocated and
+ * configured.
+ *
+ * Locking: tty_mutex for now
+ */
+static int tty_driver_install_tty(struct tty_driver *driver,
+ struct tty_struct *tty)
+{
+ int idx = tty->index;
+
+ if (driver->ops->install)
+ return driver->ops->install(driver, tty);
+
+ if (tty_init_termios(tty) == 0) {
+ tty_driver_kref_get(driver);
+ tty->count++;
+ driver->ttys[idx] = tty;
+ return 0;
+ }
+ return -ENOMEM;
+}
+
+/**
+ * tty_driver_remove_tty() - remove a tty from the driver tables
+ * @driver: the driver for the tty
+ * @idx: the minor number
+ *
+ * Remvoe a tty object from the driver tables. The tty->index field
+ * will be set by the time this is called.
+ *
+ * Locking: tty_mutex for now
+ */
+static void tty_driver_remove_tty(struct tty_driver *driver,
+ struct tty_struct *tty)
+{
+ if (driver->ops->remove)
+ driver->ops->remove(driver, tty);
+ else
+ driver->ttys[tty->index] = NULL;
+}
+
+/*
+ * tty_reopen() - fast re-open of an open tty
+ * @tty - the tty to open
*
* Return 0 on success, -errno on error.
*
* relaxed for the (most common) case of reopening a tty.
*/
-int tty_init_dev(struct tty_driver *driver, int idx,
- struct tty_struct **ret_tty, int first_ok)
+struct tty_struct *tty_init_dev(struct tty_driver *driver, int idx,
+ int first_ok)
{
- struct tty_struct *tty, *o_tty;
- struct ktermios *tp, **tp_loc, *o_tp, **o_tp_loc;
- struct ktermios *ltp, **ltp_loc, *o_ltp, **o_ltp_loc;
- int retval = 0;
-
- /* check whether we're reopening an existing tty */
- tty = tty_driver_lookup_tty(driver, idx);
- if (IS_ERR(tty)) {
- retval = PTR_ERR(tty);
- goto end_init;
- }
-
- if (tty) {
- retval = tty_reopen(tty);
- if (retval)
- return retval;
- *ret_tty = tty;
- return 0;
- }
+ struct tty_struct *tty;
+ int retval;
/* Check if pty master is being opened multiple times */
if (driver->subtype == PTY_TYPE_MASTER &&
- (driver->flags & TTY_DRIVER_DEVPTS_MEM) && !first_ok) {
- retval = -EIO;
- goto end_init;
- }
+ (driver->flags & TTY_DRIVER_DEVPTS_MEM) && !first_ok)
+ return ERR_PTR(-EIO);
+
/*
* First time open is complex, especially for PTY devices.
* This code guarantees that either everything succeeds and the
* and locked termios may be retained.)
*/
- if (!try_module_get(driver->owner)) {
- retval = -ENODEV;
- goto end_init;
- }
-
- o_tty = NULL;
- tp = o_tp = NULL;
- ltp = o_ltp = NULL;
+ if (!try_module_get(driver->owner))
+ return ERR_PTR(-ENODEV);
tty = alloc_tty_struct();
if (!tty)
goto fail_no_mem;
- initialize_tty_struct(tty);
- tty->driver = driver;
- tty->ops = driver->ops;
- tty->index = idx;
- tty_line_name(driver, idx, tty->name);
+ initialize_tty_struct(tty, driver, idx);
- if (driver->flags & TTY_DRIVER_DEVPTS_MEM) {
- tp_loc = &tty->termios;
- ltp_loc = &tty->termios_locked;
- } else {
- tp_loc = &driver->termios[idx];
- ltp_loc = &driver->termios_locked[idx];
- }
-
- if (!*tp_loc) {
- tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
- if (!tp)
- goto free_mem_out;
- *tp = driver->init_termios;
- }
-
- if (!*ltp_loc) {
- ltp = kzalloc(sizeof(struct ktermios), GFP_KERNEL);
- if (!ltp)
- goto free_mem_out;
- }
-
- if (driver->type == TTY_DRIVER_TYPE_PTY) {
- o_tty = alloc_tty_struct();
- if (!o_tty)
- goto free_mem_out;
- if (!try_module_get(driver->other->owner)) {
- /* This cannot in fact currently happen */
- free_tty_struct(o_tty);
- o_tty = NULL;
- goto free_mem_out;
- }
- initialize_tty_struct(o_tty);
- o_tty->driver = driver->other;
- o_tty->ops = driver->ops;
- o_tty->index = idx;
- tty_line_name(driver->other, idx, o_tty->name);
-
- if (driver->flags & TTY_DRIVER_DEVPTS_MEM) {
- o_tp_loc = &o_tty->termios;
- o_ltp_loc = &o_tty->termios_locked;
- } else {
- o_tp_loc = &driver->other->termios[idx];
- o_ltp_loc = &driver->other->termios_locked[idx];
- }
-
- if (!*o_tp_loc) {
- o_tp = kmalloc(sizeof(struct ktermios), GFP_KERNEL);
- if (!o_tp)
- goto free_mem_out;
- *o_tp = driver->other->init_termios;
- }
-
- if (!*o_ltp_loc) {
- o_ltp = kzalloc(sizeof(struct ktermios), GFP_KERNEL);
- if (!o_ltp)
- goto free_mem_out;
- }
-
- /*
- * Everything allocated ... set up the o_tty structure.
- */
- if (!(driver->other->flags & TTY_DRIVER_DEVPTS_MEM))
- driver->other->ttys[idx] = o_tty;
- if (!*o_tp_loc)
- *o_tp_loc = o_tp;
- if (!*o_ltp_loc)
- *o_ltp_loc = o_ltp;
- o_tty->termios = *o_tp_loc;
- o_tty->termios_locked = *o_ltp_loc;
- 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;
+ retval = tty_driver_install_tty(driver, tty);
+ if (retval < 0) {
+ free_tty_struct(tty);
+ module_put(driver->owner);
+ return ERR_PTR(retval);
}
/*
- * 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.
- *
- * FIXME: We want a 'driver->install method ?
- */
- if (!(driver->flags & TTY_DRIVER_DEVPTS_MEM))
- driver->ttys[idx] = tty;
-
- if (!*tp_loc)
- *tp_loc = tp;
- if (!*ltp_loc)
- *ltp_loc = ltp;
- tty->termios = *tp_loc;
- tty->termios_locked = *ltp_loc;
- /* 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_driver_kref_get(driver);
- tty->count++;
-
- /*
* Structures all installed ... call the ldisc open routines.
* If we fail here just call release_tty to clean up. No need
* to decrement the use counts, as release_tty doesn't care.
*/
- retval = tty_ldisc_setup(tty, o_tty);
-
+ retval = tty_ldisc_setup(tty, tty->link);
if (retval)
goto release_mem_out;
-
- *ret_tty = tty;
- /* All paths come through here to release the mutex */
-end_init:
- return retval;
-
- /* Release locally allocated memory ... nothing placed in slots */
-free_mem_out:
- kfree(o_tp);
- if (o_tty) {
- module_put(o_tty->driver->owner);
- free_tty_struct(o_tty);
- }
- kfree(ltp);
- kfree(tp);
- free_tty_struct(tty);
+ return tty;
fail_no_mem:
module_put(driver->owner);
- retval = -ENOMEM;
- goto end_init;
+ return ERR_PTR(-ENOMEM);
/* call the tty release_tty routine to clean out this slot */
release_mem_out:
printk(KERN_INFO "tty_init_dev: ldisc open failed, "
"clearing slot %d\n", idx);
release_tty(tty, idx);
- goto end_init;
+ return ERR_PTR(retval);
}
void tty_free_termios(struct tty_struct *tty)
void tty_shutdown(struct tty_struct *tty)
{
- tty->driver->ttys[tty->index] = NULL;
+ tty_driver_remove_tty(tty->driver, tty);
tty_free_termios(tty);
}
EXPORT_SYMBOL(tty_shutdown);
int devpts;
int idx;
char buf[64];
+ struct inode *inode;
+ inode = filp->f_path.dentry->d_inode;
tty = (struct tty_struct *)filp->private_data;
- if (tty_paranoia_check(tty, filp->f_path.dentry->d_inode,
- "tty_release_dev"))
+ if (tty_paranoia_check(tty, inode, "tty_release_dev"))
return;
check_tty_count(tty, "tty_release_dev");
"free (%s)\n", tty->name);
return;
}
- if (!(tty->driver->flags & TTY_DRIVER_DEVPTS_MEM)) {
+ if (!devpts) {
if (tty != tty->driver->ttys[idx]) {
printk(KERN_DEBUG "tty_release_dev: driver.table[%d] not tty "
"for (%s)\n", idx, tty->name);
/* Make this pty number available for reallocation */
if (devpts)
- devpts_kill_index(idx);
+ devpts_kill_index(inode, idx);
}
/**
static int __tty_open(struct inode *inode, struct file *filp)
{
- struct tty_struct *tty;
+ struct tty_struct *tty = NULL;
int noctty, retval;
struct tty_driver *driver;
int index;
return -ENODEV;
}
got_driver:
- retval = tty_init_dev(driver, index, &tty, 0);
+ if (!tty) {
+ /* check whether we're reopening an existing tty */
+ tty = tty_driver_lookup_tty(driver, inode, index);
+
+ if (IS_ERR(tty))
+ return PTR_ERR(tty);
+ }
+
+ if (tty) {
+ retval = tty_reopen(tty);
+ if (retval)
+ tty = ERR_PTR(retval);
+ } else
+ tty = tty_init_dev(driver, index, 0);
+
mutex_unlock(&tty_mutex);
tty_driver_kref_put(driver);
- if (retval)
- return retval;
+ if (IS_ERR(tty))
+ return PTR_ERR(tty);
filp->private_data = tty;
file_move(filp, &tty->tty_files);
* Locking: none - tty in question must not be exposed at this point
*/
-static void initialize_tty_struct(struct tty_struct *tty)
+void initialize_tty_struct(struct tty_struct *tty,
+ struct tty_driver *driver, int idx)
{
memset(tty, 0, sizeof(struct tty_struct));
kref_init(&tty->kref);
spin_lock_init(&tty->ctrl_lock);
INIT_LIST_HEAD(&tty->tty_files);
INIT_WORK(&tty->SAK_work, do_SAK_work);
+
+ tty->driver = driver;
+ tty->ops = driver->ops;
+ tty->index = idx;
+ tty_line_name(driver, idx, tty->name);
}
/**
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff